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Neuroprotective effects of intranasal extracellular vesicles from human platelet concentrates supernatants in traumatic brain injury and Parkinson’s disease models

The burgeoning field of regenerative medicine has significantly advanced with recent findings on biotherapies using human platelet lysates (HPLs), derived from clinical-grade platelet concentrates (PCs), for t...

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Dengue NS1 interaction with lipids alters its pathogenic effects on monocyte derived macrophages

While dengue NS1 antigen has been shown to be associated with disease pathogenesis in some studies, it has not been linked in other studies, with the reasons remaining unclear. NS1 antigen levels in acute deng...

Extracellular vesicle therapy in neurological disorders

Extracellular vesicles (EVs) are vital for cell-to-cell communication, transferring proteins, lipids, and nucleic acids in various physiological and pathological processes. They play crucial roles in immune mo...

Machine learning enabled classification of lung cancer cell lines co-cultured with fibroblasts with lightweight convolutional neural network for initial diagnosis

Identification of lung cancer subtypes is critical for successful treatment in patients, especially those in advanced stages. Many advanced and personal treatments require knowledge of specific mutations, as w...

Beyond glycan barriers: non-cognate ligands and protein mimicry approaches to elicit broadly neutralizing antibodies for HIV-1

Human immunodeficiency virus type 1 (HIV-1) vaccine immunogens capable of inducing broadly neutralizing antibodies (bNAbs) remain obscure. HIV-1 evades immune responses through enormous diversity and hides its...

Plexin C1 influences immune response to intracellular LPS and survival in murine sepsis

Intracellular sensing of lipopolysaccharide (LPS) is essential for the immune response against gram-negative bacteria and results in activation of caspase-11 and pyroptotic cell death with fatal consequences i...

EpCAM-targeted betulinic acid analogue nanotherapy improves therapeutic efficacy and induces anti-tumorigenic immune response in colorectal cancer tumor microenvironment

Betulinic acid (BA) has been well investigated for its antiproliferative and mitochondrial pathway-mediated apoptosis-inducing effects on various cancers. However, its poor solubility and off-target activity h...

Low-level HIV-1 viremia affects T-cell activation and senescence in long-term treated adults in the INSTI era

Around 10% of people with HIV (PWH) exhibit a low-level viremia (LLV) under antiretroviral therapy (ART). However, its origin and clinical significance are largely unknown, particularly at viremias between 50 ...

Gene therapy for ultrarare diseases: a geneticist’s perspective

Gene therapy has made considerable strides in recent years. More than 4000 protein-coding genes have been implicated in more than 6000 genetic diseases; next-generation sequencing has dramatically revolutioniz...

Targeted nanotherapeutics for the treatment of Helicobacter pylori infection

Helicobacter pylori infection is involved in gastric diseases such as peptic ulcer and adenocarcinoma. Approved antibiotherapies still fail in 10 to 40% of the infected patients and, in this scenario, targeted na...

Variants of human DECTIN-1 rs16910526 are linked to differential reactive oxygen species production and susceptibility to tuberculosis

Dectin-1 is a transmembrane receptor that plays a pivotal role in recognising fungi and Mycobacterium tuberculosis (Mtb) . A specific variant, DECTIN-1 rs16910526, results in a truncated receptor that disrupts mem...

Retraction Note: Inhibitors of apoptosis proteins in experimental benign prostatic hyperplasia: effects of Serenoa repens , selenium and lycopene

Development of novel antimicrobials with engineered endolysin lysecd7-smap to combat gram-negative bacterial infections.

Among the non-traditional antibacterial agents in development, only a few targets critical Gram-negative bacteria such as carbapenem-resistant Pseudomonas aeruginosa , Acinetobacter baumannii or cephalosporin-resi...

BUB1B monoallelic germline variants contribute to prostate cancer predisposition by triggering chromosomal instability

Prostate cancer (PrCa) is the most frequently diagnosed cancer in men. Variants in known moderate- to high-penetrance genes explain less than 5% of the cases arising at early-onset (< 56 years) and/or with fam...

Enteroviruses: epidemic potential, challenges and opportunities with vaccines

Enteroviruses (EVs) are the most prevalent viruses in humans. EVs can cause a range of acute symptoms, from mild common colds to severe systemic infections such as meningitis, myocarditis, and flaccid paralysi...

Intracellular domain of epithelial cell adhesion molecule induces Wnt receptor transcription to promote colorectal cancer progression

Epithelial cell adhesion molecule (EpCAM) has been widely studied as a tumor antigen due to its expression in varieties of solid tumors. Moreover, the glycoprotein contributes to critical cancer-associated cel...

Unraveling the differential mechanisms of revascularization promoted by MSCs & ECFCs from adipose tissue or umbilical cord in a murine model of critical limb-threatening ischemia

Critical limb-threatening ischemia (CLTI) constitutes the most severe manifestation of peripheral artery disease, usually induced by atherosclerosis. CLTI patients suffer from high risk of amputation of the lo...

A glimpse into viral warfare: decoding the intriguing role of highly pathogenic coronavirus proteins in apoptosis regulation

Coronaviruses employ various strategies for survival, among which the activation of endogenous or exogenous apoptosis stands out, with viral proteins playing a pivotal role. Notably, highly pathogenic coronavi...

CPEB2-activated axonal translation of VGLUT2 mRNA promotes glutamatergic transmission and presynaptic plasticity

Local translation at synapses is important for rapidly remodeling the synaptic proteome to sustain long-term plasticity and memory. While the regulatory mechanisms underlying memory-associated local translatio...

Dual inhibition of SUMOylation and MEK conquers MYC-expressing KRAS -mutant cancers by accumulating DNA damage

KRAS mutations frequently occur in cancers, particularly pancreatic ductal adenocarcinoma, colorectal cancer, and non-small cell lung cancer. Although KRAS G12C inhibitors have recently been approved, effective pr...

Exosomes: a review of biologic function, diagnostic and targeted therapy applications, and clinical trials

Exosomes are extracellular vesicles generated by all cells and they carry nucleic acids, proteins, lipids, and metabolites. They mediate the exchange of substances between cells,thereby affecting biological pr...

Cholestasis-induced phenotypic transformation of neutrophils contributes to immune escape of colorectal cancer liver metastasis

Cholestasis is a common yet severe complication that occurs during the advancement of liver metastasis. However, how cholestasis impacts the development, treatment, and tumor microenvironment (TME) of liver me...

Enterovirus-A71 exploits RAB11 to recruit chaperones for virus morphogenesis

Enterovirus 71 (EV-A71) causes Hand, Foot and Mouth Disease (HFMD) in children and has been associated with neurological complications. The molecular mechanisms involved in EV-A71 pathogenesis have remained el...

The double whammy of ER-retention and dominant-negative effects in numerous autosomal dominant diseases: significance in disease mechanisms and therapy

The endoplasmic reticulum (ER) employs stringent quality control mechanisms to ensure the integrity of protein folding, allowing only properly folded, processed and assembled proteins to exit the ER and reach ...

Beyond traditional translation: ncRNA derived peptides as modulators of tumor behaviors

Within the intricate tapestry of molecular research, noncoding RNAs (ncRNAs) were historically overshadowed by a pervasive presumption of their inability to encode proteins or peptides. However, groundbreaking...

Adipocyte pyroptosis occurs in omental tumor microenvironment and is associated with chemoresistance of ovarian cancer

Ovarian carcinoma (OC) is a fatal malignancy, with most patients experiencing recurrence and resistance to chemotherapy. In contrast to hematogenous metastasizing tumors, ovarian cancer cells disseminate withi...

Correction: Excess glucose alone depress young mesenchymal stromal/stem cell osteogenesis and mitochondria activity within hours/days via NAD + / SIRT1 axis

The original article was published in Journal of Biomedical Science 2024 31 :49

The glycosylation deficiency of flavivirus NS1 attenuates virus replication through interfering with the formation of viral replication compartments

Flavivirus is a challenge all over the world. The replication of flavivirus takes place within membranous replication compartments (RCs) derived from endoplasmic reticulum (ER). Flavivirus NS1 proteins have be...

Osteosarcoma in a ceRNET perspective

Osteosarcoma (OS) is the most prevalent and fatal type of bone tumor. It is characterized by great heterogeneity of genomic aberrations, mutated genes, and cell types contribution, making therapy and patients ...

Immunoglobulin and T cell receptor repertoire changes induced by a prototype vaccine against Chagas disease in naïve rhesus macaques

A vaccine against Trypanosoma cruzi , the agent of Chagas disease, would be an excellent additional tool for disease control. A recombinant vaccine based on Tc24 and TSA1 parasite antigens was found to be safe and...

Revolution in sepsis: a symptoms-based to a systems-based approach?

Severe infection and sepsis are medical emergencies. High morbidity and mortality are linked to CNS dysfunction, excessive inflammation, immune compromise, coagulopathy and multiple organ dysfunction. Males ap...

Development of a highly effective combination monoclonal antibody therapy against Herpes simplex virus

Infections with Herpes simplex virus (HSV)-1 or -2 usually present as mild chronic recurrent disease, however in rare cases can result in life-threatening conditions with a large spectrum of pathology. Monoclo...

USP9X-mediated REV1 deubiquitination promotes lung cancer radioresistance via the action of REV1 as a Rad18 molecular scaffold for cystathionine γ-lyase

Radioresistance is a key clinical constraint on the efficacy of radiotherapy in lung cancer patients. REV1 DNA directed polymerase (REV1) plays an important role in repairing DNA damage and maintaining genomic...

Tumor necrosis factor-inducible gene 6 protein and its derived peptide ameliorate liver fibrosis by repressing CD44 activation in mice with alcohol-related liver disease

Alcohol-related liver disease (ALD) is a major health concern worldwide, but effective therapeutics for ALD are still lacking. Tumor necrosis factor-inducible gene 6 protein (TSG-6), a cytokine released from m...

Characterization of the genetic variation and evolutionary divergence of the CLEC18 family

The C-type lectin family 18 (CLEC18) with lipid and glycan binding capabilities is important to metabolic regulation and innate immune responses against viral infection. However, human CLEC18 comprises three p...

Pivotal functions and impact of long con-coding RNAs on cellular processes and genome integrity

Recent advances in uncovering the mysteries of the human genome suggest that long non-coding RNAs (lncRNAs) are important regulatory components. Although lncRNAs are known to affect gene transcription, their m...

Somatic PDGFRB activating variants promote smooth muscle cell phenotype modulation in intracranial fusiform aneurysm

The fusiform aneurysm is a nonsaccular dilatation affecting the entire vessel wall over a short distance. Although PDGFRB somatic variants have been identified in fusiform intracranial aneurysms, the molecular...

A G-quadruplex-binding platinum complex induces cancer mitochondrial dysfunction through dual-targeting mitochondrial and nuclear G4 enriched genome

G-quadruplex DNA (G4) is a non-canonical structure forming in guanine-rich regions, which play a vital role in cancer biology and are now being acknowledged in both nuclear and mitochondrial (mt) genome. Howev...

Excess glucose alone depress young mesenchymal stromal/stem cell osteogenesis and mitochondria activity within hours/days via NAD + /SIRT1 axis

The impact of global overconsumption of simple sugars on bone health, which peaks in adolescence/early adulthood and correlates with osteoporosis (OP) and fracture risk decades, is unclear. Mesenchymal stromal...

The Correction to this article has been published in Journal of Biomedical Science 2024 31 :61

Contribution of extracellular vesicles for the pathogenesis of retinal diseases: shedding light on blood-retinal barrier dysfunction

Retinal degenerative diseases, including diabetic retinopathy (DR) and age-related macular degeneration (AMD), loom as threats to vision, causing detrimental effects on the structure and function of the retina...

Exploiting urine-derived induced pluripotent stem cells for advancing precision medicine in cell therapy, disease modeling, and drug testing

The field of regenerative medicine has witnessed remarkable advancements with the emergence of induced pluripotent stem cells (iPSCs) derived from a variety of sources. Among these, urine-derived induced pluri...

Targeting cathepsin S promotes activation of OLF1-BDNF/TrkB axis to enhance cognitive function

Cathepsin S (CTSS) is a cysteine protease that played diverse roles in immunity, tumor metastasis, aging and other pathological alterations. At the cellular level, increased CTSS levels have been associated wi...

Campylobacter jejuni virulence factors: update on emerging issues and trends

Campylobacter jejuni is a very common cause of gastroenteritis, and is frequently transmitted to humans through contaminated food products or water. Importantly, C. jejuni infections have a range of short- and l...

Membrane lipid remodeling eradicates Helicobacter pylori by manipulating the cholesteryl 6'-acylglucoside biosynthesis

Helicobacter pylori , the main cause of various gastric diseases, infects approximately half of the human population. This pathogen is auxotrophic for cholesterol which it converts to various cholesteryl α-glucosi...

Dengue virus pathogenesis and host molecular machineries

Dengue viruses (DENV) are positive-stranded RNA viruses belonging to the Flaviviridae family. DENV is the causative agent of dengue, the most rapidly spreading viral disease transmitted by mosquitoes. Each yea...

Targeting NLRP3 signaling reduces myocarditis-induced arrhythmogenesis and cardiac remodeling

Myocarditis substantially increases the risk of ventricular arrhythmia. Approximately 30% of all ventricular arrhythmia cases in patients with myocarditis originate from the right ventricular outflow tract (RV...

T cell expressions of aberrant gene signatures and Co-inhibitory receptors (Co-IRs) as predictors of renal damage and lupus disease activity

Systemic lupus erythematosus (SLE) is distinguished by an extensive range of clinical heterogeneity with unpredictable disease flares and organ damage. This research investigates the potential of aberrant sign...

Applications of peptides in nanosystems for diagnosing and managing bacterial sepsis

Sepsis represents a critical medical condition stemming from an imbalanced host immune response to infections, which is linked to a significant burden of disease. Despite substantial efforts in laboratory and ...

Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19

High levels of neutrophil extracellular trap (NET) formation or NETosis and autoantibodies are related to poor prognosis and disease severity of COVID-19 patients. Human angiotensin-converting enzyme 2 (ACE2) ...

Attenuating mitochondrial dysfunction and morphological disruption with PT320 delays dopamine degeneration in MitoPark mice

Mitochondria are essential organelles involved in cellular energy production. Changes in mitochondrial function can lead to dysfunction and cell death in aging and age-related disorders. Recent research sugges...

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• Published: 07 December 2020

2021: research and medical trends in a post-pandemic world

• Mike May 1  

Nature Medicine volume  26 ,  pages 1808–1809 ( 2020 ) Cite this article

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Goodbye 2020, a year of arguably too many challenges for the world. As tempting as it is to leave this year behind, the biomedical community is forever changed by the pandemic, while business as usual needs to carry on. Looking forward to a new year, experts share six trends for the biomedical community in 2021.

Summing up 2020, Sharon Peacock, director of the COVID-19 Genomics UK Consortium, says “we’ve seen some excellent examples of people working together from academia, industry, and healthcare sectors...I’m hopeful that will stay with us going into 2021.” Nonetheless, we have lost ground and momentum in non-COVID research, she says. “This could have a profound effect on our ability to research other areas in the future.”

The coronavirus SARS-CoV-2 has already revealed weaknesses in medical research and clinical capabilities, as well as opportunities. Although it is too soon to know when countries around the world will control the COVID-19 pandemic, there is already much to be learned.

To explore trends for 2021, we talked to experts from around the world who specialize in medical research. Here is what we learned.

1. The new normal

Marion Koopman, head of the Erasmus MC Department of Viroscience, predicts that emerging-disease experts will overwhelmingly remain focused on SARS-CoV-2, at least for the coming year.

“I really hope we will not go back to life as we used to know it, because that would mean that the risk of emerging diseases and the need for an ambitious preparedness research agenda would go to the back burner,” Koopman says. “That cannot happen.”

Scientists must stay prepared, because the virus keeps changing. Already, Koopman says, “We have seen spillback [of SARS-CoV-2] into mink in our country, and ongoing circulation with accumulation of mutations in the spike and other parts of the genome.”

Juleen R. Zierath, an expert in the physiological mechanisms of metabolic diseases at the Karolinska Institute and the University of Copenhagen, points out that the pandemic “has raised attention to deleterious health consequences of metabolic diseases, including obesity and type 2 diabetes,” because people with these disorders have been “disproportionally affected by COVID-19.” She notes that the coupling of the immune system to metabolism at large probably deserves more attention.

2. Trial by fire for open repositories

The speed of SARS-CoV-2’s spread transformed how scientists disseminate information. “There is an increased use of open repositories such as bioRxiv and medRxiv, enabling faster dissemination of study and trial results,” says Alan Karthikesalingam, Research Lead at Google Health UK. “When paired with the complementary — though necessarily slower — approach of peer review that safeguards rigor and quality, this can result in faster innovation.”

“I suspect that the way in which we communicate ongoing scientific developments from our laboratories will change going forward,” Zierath says. That is already happening, with many meetings going to virtual formats.

Deborah Johnson, president and CEO of the Keystone Symposia on Molecular and Cellular Biology, notes that while virtual events cannot fully replace the networking opportunities that are created with in-person meetings, “virtual events have democratized access to biomedical research conferences, enabling greater participation from young investigators and those from low-and-middle-income countries.” Even when in-person conferences return, she says, “it will be important to continue to offer virtual components that engage these broader audiences.”

3. Leaps and bounds for immunology

Basic research on the immune system, catapulted to the frontlines of the COVID-19 response, has received a boost in attention this year, and more research in that field could pay off big going forward.

Immunobiologist Akiko Iwasaki at the Yale School of Medicine hopes that the pandemic will drive a transformation in immunology. “It has become quite clear over decades of research that mucosal immunity against respiratory, gastrointestinal, and sexually transmitted infections is much more effective in thwarting off invading pathogens than systemic immunity,” she says. “Yet, the vast majority of vaccine efforts are put into parenteral vaccines.”

“It is time for the immunology field to do a deep dive in understanding fundamental mechanisms of protection at the mucosal surfaces, as well as to developing strategies that allow the immune response to be targeted to the mucosal surfaces,” she explains.

“We are discovering that the roles of immune cells extend far beyond what was previously thought, to play underlying roles in health and disease across all human systems, from cancer to mental health,” says Johnson.

She sees this knowledge leading to more engineered immune cells to treat diseases. “Cancer immunotherapies will likely serve as the proving ground for immune-mediated therapies against many other diseases that we are only starting to see through the lens of the immune system.”

4. Rewind time for neurodegeneration

Oskar Hansson, research team manager of Lund University’s Clinical Memory Research, expects the trend of attempting to intervene against neurodegenerative disease before widespread neurodegeneration, and even before symptom onset, to continue next year.

This approach has already shown potential. “Several promising disease-modifying therapies against Alzheimer’s disease are now planned to be evaluated in this early pre-symptomatic disease phase,” he says, “and I think we will have similar developments in other areas like Parkinson’s disease and [amyotrophic lateral sclerosis].”

Delving deeper into such treatments depends on better understanding of how neurodegeneration develops. As Hansson notes, the continued development of cohort studies from around the world will help scientists “study how different factors — genetics, development, lifestyle, etcetera — affect the initiation and evolution of even the pre-symptomatic stages of the disease, which most probably will result in a much deeper understanding of the disease as well as discovery of new drug targets.”

5. Digital still front and center

“As [artificial intelligence] algorithms around the world begin to be released more commonly in regulated medical device software, I think there will be an increasing trend toward prospective research examining algorithmic robustness, safety, credibility and fairness in real-world medical settings,” says Karthikesalingam. “The opportunity for clinical and machine-learning research to improve patient outcomes in this setting is substantial.”

However, more trials are needed to prove which artificial intelligence works in medicine and which does not. Eric Topol, a cardiologist who combines genomic and digital medicine in his work at Scripps Research, says “there are not many big, annotated sets of data on, for example, scans, and you need big datasets to train new algorithms.” Otherwise, only unsupervised learning algorithms can be used, and “that’s trickier,” he says.

Despite today’s bottlenecks in advancing digital health, Topol remains very optimistic. “Over time, we’ll see tremendous progress across all modalities — imaging data, speech data, and text data — to gather important information through patient tests, research articles or reviewing patient chats,” he says.

He envisions that speech-recognition software could, for instance, capture physician–patient talks and turn them into notes. “Doctors will love this,” he says, “and patients will be able to look a doctor in the eye, which enhances the relationship.”

6. ‘Be better prepared’ — a new medical mantra

One trend that every expert interviewed has emphasized is the need for preparation. As Gabriel Leung, a specialist in public-health medicine at the University of Hong Kong, put it, “We need a readiness — not just in technology platforms but also business cases — to have a sustained pipeline of vaccines and therapies, so that we would not be scrambling for some of the solutions in the middle of a pandemic.”

Building social resilience ahead of a crisis is also important. “[SARS-CoV-2] and the resulting pandemic make up the single most important watershed in healthcare,” Leung explains. “The justice issue around infection risk, access to testing and treatment — thus outcomes — already make up the single gravest health inequity in the last century.”

One change that Peacock hopes for in the near future is the sequencing of pathogens on location, instead of more centrally. “For pathogen sequencing, you need to be able to apply it where the problem under investigation is happening,” she explains. “In the UK, COVID-19 has been the catalyst for us to develop a highly collaborative, distributed network of sequencing capabilities.”

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May, M. 2021: research and medical trends in a post-pandemic world. Nat Med 26 , 1808–1809 (2020). https://doi.org/10.1038/s41591-020-01146-z

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New study finds semaglutide safe for brain health with possible benefits for cognition and nicotine dependence

11th July 2024

Semaglutide – widely known as Ozempic/Wegovy – does not negatively impact brain health and is associated with lower risk of cognitive problems and less nicotine dependence, according to a new study.

The analysis, conducted by researchers from the University of Oxford and supported by the National Institute for Health Research (NIHR) Oxford Health Biomedical Research Centre and the Medical Research Council , revealed that taking the drug, a popular medication for type II diabetes, had no increased risk of adverse neurological or psychiatric outcomes compared to other antidiabetic medications, challenging recent concerns about the drug’s safety.

The comprehensive analysis, published in the journal eClinicalMedicine , used more than 100 million patient records in the USA including over 20,000 who were taking semaglutide. It found that semaglutide:

• Was not associated with an increased risk of neurological and psychiatric conditions, such as dementia, depression, or anxiety, compared to other common anti-diabetic medications
• Was associated with a lower risk of cognitive problems and nicotine dependence.

“Our results suggest that semaglutide use could extend beyond managing diabetes, potentially offering unexpected benefits in the treatment and prevention of cognitive decline and substance misuse,” said Dr Riccardo De Giorgi , Clinical Lecturer at the University of Oxford and lead author of the study. “The findings of our study therefore not only help reassure the millions of patients relying on semaglutide for diabetes management, but, if confirmed, might also have significant implications for public health in terms of reducing cognitive deficit and smoking rates among patients with diabetes.”

While the study’s robust methodology and extensive data provide strong evidence, researchers say further investigation is needed and that it remains unclear how semaglutide may be having these effects.

“Our study is observational and these results should therefore be replicated in a randomised controlled trial to confirm and extend our findings,” said Dr Max Taquet, Clinical Lecturer at the University of Oxford and senior author of the study. “Nevertheless, they are good news for patients with psychiatric disorders, who are at an increased risk of diabetes.”

Dr De Giorgi adds that while semaglutide is also used in people with obesity, with some diabetes patients also presenting with a higher weight, the findings from this study cannot be applied to people who do not have diabetes.

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U of I Receives Over $11 Million to Launch Research Center in Women’s Nutrition and Health

April 10, 2024.

MOSCOW, Idaho — The National Institutes of Health (NIH) has awarded University of Idaho more than $11 million toward creating a biomedical research center focused on furthering studies on women’s health and nutrition.

Shelley McGuire , professor of nutrition and director of the Margaret Ritchie School of Family and Consumer Sciences (FCS), recently received confirmation of her successful application for the NIH Center of Biomedical Research Excellence (COBRE) grant and will serve as project director and principal investigator. McGuire, a maternal-infant nutritionist with expertise in breastfeeding and lactation, was recently elected to the National Academy of Medicine .

“It’s going to bolster our ability to do high-level, federally funded research on a topic that should be important to every single human,” McGuire said. “We are hoping to have impacts in the state, region and nation.”

American women face a heightened risk of malnutrition — 12% struggle with anemia while 60% are overweight. Malnutrition is an especially serious problem in Idaho, where 12% of the general population is food insecure, compared with 10% nationally.

“The whole topic of health and nutrition in women is important from early life, through breastfeeding, through pregnancy and all the way until women get older when we have a higher risk of poor health outcomes like osteoporosis and specific types of cancer,” McGuire said.

The COBRE will span five years, retroactive to Jan. 1, in its initial phase, and U of I will be eligible to apply for two additional five-year phases of funding. Furthermore, researchers from any U of I college will be eligible to apply for up to $100,000 per year in combined funds for relevant pilot projects, and McGuire has already received inquiries about the opportunity from faculty members in four colleges.

The funds will cover two administrative staff members and four new faculty positions — two FCS faculty members, a health psychologist within the Department of Psychology and Communication Studies and an expert at analyzing large datasets or data related to nutrition and women’s health within the Department of Mathematics and Statistical Science.

The COBRE names three initial research project leaders:

• Yimin Chen , an assistant professor in FCS specializing in maternal nutrition and human milk composition, will study the impact of postpartum vitamin D supplementation on maternal depression.
• Ginny Lane , an assistant professor in FCS specializing in community and global nutrition, will study type 2 diabetes among Hispanic women living in Idaho.
• Ann Brown , an associate professor of exercise physiology and associate dean of graduate studies in the College of Education, Health and Human Sciences, will study the health ramifications for women, including college-age athletes, of having a normal body weight but still carrying excess fat tissue similar to that of an obese person.

The COBRE’s administrative team will also include Mark McGuire , university distinguished professor and associate dean of research and director of the Idaho Agricultural Experiment Station, and Janet Williams , a senior research scientist with the Department of Animal, Veterinary and Food Sciences, who will oversee a nutrition analytics lab developed for the program.

COBRE research project leaders will receive leadership training.

“My vision is that all of these people will end up in leadership roles, and they will become a voice in academic leadership that considers rigorous research and women’s health on a daily basis,” McGuire said.

The COBRE program supports the establishment and development of innovative, state-of-the-art biomedical and behavioral research centers at institutions in states with historically poor success at landing NIH awards. Idaho ranks 49th among states at obtaining NIH funds.

McGuire’s COBRE represents the fourth COBRE in U of I’s history. U of I has one other active COBRE — the Institute for Modeling Collaboration and Innovation — which is in its ninth year and is run by Holly Wichman, a university distinguished professor in the Department of Biological Sciences.

The NIH Center of Biomedical Research Excellence (COBRE) in Nutrition and Women's Health is funded with a five-year, $11,183,222 grant, of which 100% is the federal share, through the National Institute of Health under award number 1P20GM152304-01.

Media Contacts:

John O’Connell Assistant Director of Communications, College of Agricultural and Life Sciences 208-530-5959 [email protected]

Shelley McGuire Professor and Director, Margaret Ritchie School of Family and Consumer Sciences 208-885-6546 [email protected]

About the University of Idaho

The University of Idaho, home of the Vandals, is Idaho’s land-grant, national research university. From its residential campus in Moscow, U of I serves the state of Idaho through educational centers in Boise, Coeur d’Alene and Idaho Falls, nine research and Extension centers, plus Extension offices in 42 counties. Home to nearly 11,000 students statewide, U of I is a leader in student-centered learning and excels at interdisciplinary research, service to businesses and communities, and in advancing diversity, citizenship and global outreach. U of I competes in the Big Sky and Western Athletic conferences. Learn more at uidaho.edu .

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Study to Evaluate THC, CBD Benefits for Dementia-Related Agitation

September 3, 2024 · Baton Rouge, LA

Pennington Biomedical currently recruiting hospice-eligible dementia patients “LiBBY” research study 

Pennington Biomedical Research Center’s Dr. Jeff Keller is evaluating the potential for delta-9-tetrahydrocannabinol, or THC, and cannabidiol, or CBD, to reduce the behaviors indicating agitation, distress or anxiety in patients with Alzheimer’s disease or other forms of dementia. The study is designed for hospice-eligible patients who are either receiving hospice care or who are eligible for hospice, and who are exhibiting agitation concurrently with a diagnosis of dementia. There are currently no FDA-approved medications to treat agitation at the end-of-life stages in dementia patients.  

The “Life’s End Benefits of Cannabidiol and Tetrahydrocannabinol” or LiBBY, study is the first-of-its-kind national study funded by the National Institute of Aging. The placebo-controlled, double-blinded study is designed to help researchers further explore these compounds for their potential to ease the burden of patients and caregivers.  

“The restlessness, anxiety, and distress that frequently accompanies Alzheimer’s and dementia can be frustrating and frightening for both the patient and their caregivers,” said Dr. Keller, who is the director of Institute for Dementia Research & Prevention at Pennington Biomedical and a professor of aging and neurodegeneration. “The LiBBY study intends to explore whether THC and CBD can be safe and effective options for managing agitation in dementia patients. This landmark, multisite study will increase the pace of THC clinical research nationwide, and Pennington Biomedical’s participation makes it much easier to initiate THC research at this facility in the future.” 

Upon joining the study, participants will complete a baseline visit and will be randomly assigned to one of two study groups: one receiving the active study drug, and one receiving a placebo. The active study will last for 12 weeks and will include one screening visit, six in-person visits, and five evaluations by phone.  

Before the study concludes, all participants will have the opportunity to request to continue their participation in the “Open Label Extension” portion of the study. Though participants will not know if they are receiving the study drug or the placebo during the study, all participants will receive the active study drug in the “Open Label Extension” period. 

“Dementia, especially when coupled with agitation, can be frightening for patients and heartbreaking for caregivers, who frequently face burnout. As other studies have shown THC can help in treating post-chemotherapy nausea, the LiBBY study is a practical next step in exploring the benefits of these compounds and offering hope to those facing this difficult challenge,” said Dr. John Kirwan, Executive Director of Pennington Biomedical. “Dr. Keller and his colleagues have worked incredibly diligently to bring this study to Pennington Biomedical. We are proud to have this study here and to have it position the Center for similar studies in the future.” 

Pennington Biomedical is one of 11 research institutions to facilitate the LiBBY study and exploring the use of THC for dementia-related agitation. Pennington Biomedical, Georgetown University Medical Center, the University of Kentucky, and the Ralph H. Johnson VA Medical Center are currently recruiting participants.

The research facility is working with hospice care providers in Capital Region and beyond to share the details of this study with patients and their families. Carpenter Health network, a large Baton Rouge-based hospice group, is one of the care providers to help identify patients and caretakers who may be eligible for the study.

"The Carpenter Health Network is proud to join with other late-stage care facilities and networks to share this study with the families we work with daily," said Raoul Manalac, Medical Director at St. Joseph Hospice – Baton Rouge. "Dementia is accompanied by many challenges, with agitation and anxiety among the most frightening and frustrating for patients and families, and there are few options available to provide relief. This innovative study is driven by both the quest for new knowledge, as well as compassion for families dealing with dementia.”  

Hospice groups and end-of-life care providers in South Louisiana will be instrumental connecting eligible patients with the study. Those providers or groups who are interested can contact Dr. Jeff Keller at [email protected] . 

For more information contact:

Joe Coussan, Media Relations Manager, [email protected] , 225-763-3049 or Ernie Ballard, Senior Director of Communications & Marketing, [email protected] , 225-263-2677 .

About the Pennington Biomedical Research Center

The Pennington Biomedical Research Center is at the forefront of medical discovery as it relates to understanding the triggers of obesity, diabetes, cardiovascular disease, cancer and dementia. The Center conducts basic, clinical, and population research, and is a campus of the LSU System. The research enterprise at Pennington Biomedical includes over 530 employees within a network of 44 clinics and research laboratories, and 13 highly specialized core service facilities. Its scientists and physician/scientists are supported by research trainees, lab technicians, nurses, dietitians, and other support personnel. Pennington Biomedical is a state-of-the-art research facility on a 222-acre campus in Baton Rouge. For more information, see www.pbrc.edu .

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• v.106(15); 2009 Apr

Types of Study in Medical Research

Bernd röhrig.

1 MDK Rheinland-Pfalz, Referat Rehabilitation/Biometrie, Alzey

Jean-Baptist du Prel

2 Zentrum für Präventive Pädiatrie, Zentrum für Kinder- und Jugendmedizin, Mainz

Daniel Wachtlin

3 Interdisziplinäres Zentrum Klinische Studien (IZKS), Fachbereich Medizin der Universität Mainz

Maria Blettner

4 Institut für Medizinische Biometrie, Epidemiologie und Informatik (IMBEI), Johannes Gutenberg Universität Mainz

The choice of study type is an important aspect of the design of medical studies. The study design and consequent study type are major determinants of a study’s scientific quality and clinical value.

This article describes the structured classification of studies into two types, primary and secondary, as well as a further subclassification of studies of primary type. This is done on the basis of a selective literature search concerning study types in medical research, in addition to the authors’ own experience.

Three main areas of medical research can be distinguished by study type: basic (experimental), clinical, and epidemiological research. Furthermore, clinical and epidemiological studies can be further subclassified as either interventional or noninterventional.

Conclusions

The study type that can best answer the particular research question at hand must be determined not only on a purely scientific basis, but also in view of the available financial resources, staffing, and practical feasibility (organization, medical prerequisites, number of patients, etc.).

The quality, reliability and possibility of publishing a study are decisively influenced by the selection of a proper study design. The study type is a component of the study design (see the article "Study Design in Medical Research") and must be specified before the study starts. The study type is determined by the question to be answered and decides how useful a scientific study is and how well it can be interpreted. If the wrong study type has been selected, this cannot be rectified once the study has started.

After an earlier publication dealing with aspects of study design, the present article deals with study types in primary and secondary research. The article focuses on study types in primary research. A special article will be devoted to study types in secondary research, such as meta-analyses and reviews. This article covers the classification of individual study types. The conception, implementation, advantages, disadvantages and possibilities of using the different study types are illustrated by examples. The article is based on a selective literature research on study types in medical research, as well as the authors’ own experience.

Classification of study types

In principle, medical research is classified into primary and secondary research. While secondary research summarizes available studies in the form of reviews and meta-analyses, the actual studies are performed in primary research. Three main areas are distinguished: basic medical research, clinical research, and epidemiological research. In individual cases, it may be difficult to classify individual studies to one of these three main categories or to the subcategories. In the interests of clarity and to avoid excessive length, the authors will dispense with discussing special areas of research, such as health services research, quality assurance, or clinical epidemiology. Figure 1 gives an overview of the different study types in medical research.

Classification of different study types

*1 , sometimes known as experimental research; *2 , analogous term: interventional; *3 , analogous term: noninterventional or nonexperimental

This scheme is intended to classify the study types as clearly as possible. In the interests of clarity, we have excluded clinical epidemiology — a subject which borders on both clinical and epidemiological research ( 3 ). The study types in this area can be found under clinical research and epidemiology.

Basic research

Basic medical research (otherwise known as experimental research) includes animal experiments, cell studies, biochemical, genetic and physiological investigations, and studies on the properties of drugs and materials. In almost all experiments, at least one independent variable is varied and the effects on the dependent variable are investigated. The procedure and the experimental design can be precisely specified and implemented ( 1 ). For example, the population, number of groups, case numbers, treatments and dosages can be exactly specified. It is also important that confounding factors should be specifically controlled or reduced. In experiments, specific hypotheses are investigated and causal statements are made. High internal validity (= unambiguity) is achieved by setting up standardized experimental conditions, with low variability in the units of observation (for example, cells, animals or materials). External validity is a more difficult issue. Laboratory conditions cannot always be directly transferred to normal clinical practice and processes in isolated cells or in animals are not equivalent to those in man (= generalizability) ( 2 ).

Basic research also includes the development and improvement of analytical procedures—such as analytical determination of enzymes, markers or genes—, imaging procedures—such as computed tomography or magnetic resonance imaging—, and gene sequencing—such as the link between eye color and specific gene sequences. The development of biometric procedures—such as statistical test procedures, modeling and statistical evaluation strategies—also belongs here.

Clinical studies

Clinical studies include both interventional (or experimental) studies and noninterventional (or observational) studies. A clinical drug study is an interventional clinical study, defined according to §4 Paragraph 23 of the Medicines Act [Arzneimittelgesetz; AMG] as "any study performed on man with the purpose of studying or demonstrating the clinical or pharmacological effects of drugs, to establish side effects, or to investigate absorption, distribution, metabolism or elimination, with the aim of providing clear evidence of the efficacy or safety of the drug."

Interventional studies also include studies on medical devices and studies in which surgical, physical or psychotherapeutic procedures are examined. In contrast to clinical studies, §4 Paragraph 23 of the AMG describes noninterventional studies as follows: "A noninterventional study is a study in the context of which knowledge from the treatment of persons with drugs in accordance with the instructions for use specified in their registration is analyzed using epidemiological methods. The diagnosis, treatment and monitoring are not performed according to a previously specified study protocol, but exclusively according to medical practice."

The aim of an interventional clinical study is to compare treatment procedures within a patient population, which should exhibit as few as possible internal differences, apart from the treatment ( 4 , e1 ). This is to be achieved by appropriate measures, particularly by random allocation of the patients to the groups, thus avoiding bias in the result. Possible therapies include a drug, an operation, the therapeutic use of a medical device such as a stent, or physiotherapy, acupuncture, psychosocial intervention, rehabilitation measures, training or diet. Vaccine studies also count as interventional studies in Germany and are performed as clinical studies according to the AMG.

Interventional clinical studies are subject to a variety of legal and ethical requirements, including the Medicines Act and the Law on Medical Devices. Studies with medical devices must be registered by the responsible authorities, who must also approve studies with drugs. Drug studies also require a favorable ruling from the responsible ethics committee. A study must be performed in accordance with the binding rules of Good Clinical Practice (GCP) ( 5 , e2 – e4 ). For clinical studies on persons capable of giving consent, it is absolutely essential that the patient should sign a declaration of consent (informed consent) ( e2 ). A control group is included in most clinical studies. This group receives another treatment regimen and/or placebo—a therapy without substantial efficacy. The selection of the control group must not only be ethically defensible, but also be suitable for answering the most important questions in the study ( e5 ).

Clinical studies should ideally include randomization, in which the patients are allocated by chance to the therapy arms. This procedure is performed with random numbers or computer algorithms ( 6 – 8 ). Randomization ensures that the patients will be allocated to the different groups in a balanced manner and that possible confounding factors—such as risk factors, comorbidities and genetic variabilities—will be distributed by chance between the groups (structural equivalence) ( 9 , 10 ). Randomization is intended to maximize homogeneity between the groups and prevent, for example, a specific therapy being reserved for patients with a particularly favorable prognosis (such as young patients in good physical condition) ( 11 ).

Blinding is another suitable method to avoid bias. A distinction is made between single and double blinding. With single blinding, the patient is unaware which treatment he is receiving, while, with double blinding, neither the patient nor the investigator knows which treatment is planned. Blinding the patient and investigator excludes possible subjective (even subconscious) influences on the evaluation of a specific therapy (e.g. drug administration versus placebo). Thus, double blinding ensures that the patient or therapy groups are both handled and observed in the same manner. The highest possible degree of blinding should always be selected. The study statistician should also remain blinded until the details of the evaluation have finally been specified.

A well designed clinical study must also include case number planning. This ensures that the assumed therapeutic effect can be recognized as such, with a previously specified statistical probability (statistical power) ( 4 , 6 , 12 ).

It is important for the performance of a clinical trial that it should be carefully planned and that the exact clinical details and methods should be specified in the study protocol ( 13 ). It is, however, also important that the implementation of the study according to the protocol, as well as data collection, must be monitored. For a first class study, data quality must be ensured by double data entry, programming plausibility tests, and evaluation by a biometrician. International recommendations for the reporting of randomized clinical studies can be found in the CONSORT statement (Consolidated Standards of Reporting Trials, www.consort-statement.org ) ( 14 ). Many journals make this an essential condition for publication.

For all the methodological reasons mentioned above and for ethical reasons, the randomized controlled and blinded clinical trial with case number planning is accepted as the gold standard for testing the efficacy and safety of therapies or drugs ( 4 , e1 , 15 ).

In contrast, noninterventional clinical studies (NIS) are patient-related observational studies, in which patients are given an individually specified therapy. The responsible physician specifies the therapy on the basis of the medical diagnosis and the patient’s wishes. NIS include noninterventional therapeutic studies, prognostic studies, observational drug studies, secondary data analyses, case series and single case analyses ( 13 , 16 ). Similarly to clinical studies, noninterventional therapy studies include comparison between therapies; however, the treatment is exclusively according to the physician’s discretion. The evaluation is often retrospective. Prognostic studies examine the influence of prognostic factors (such as tumor stage, functional state, or body mass index) on the further course of a disease. Diagnostic studies are another class of observational studies, in which either the quality of a diagnostic method is compared to an established method (ideally a gold standard), or an investigator is compared with one or several other investigators (inter-rater comparison) or with himself at different time points (intra-rater comparison) ( e1 ). If an event is very rare (such as a rare disease or an individual course of treatment), a single-case study, or a case series, are possibilities. A case series is a study on a larger patient group with a specific disease. For example, after the discovery of the AIDS virus, the Center for Disease Control (CDC) in the USA collected a case series of 1000 patients, in order to study frequent complications of this infection. The lack of a control group is a disadvantage of case series. For this reason, case series are primarily used for descriptive purposes ( 3 ).

Epidemiological studies

The main point of interest in epidemiological studies is to investigate the distribution and historical changes in the frequency of diseases and the causes for these. Analogously to clinical studies, a distinction is made between experimental and observational epidemiological studies ( 16 , 17 ).

Interventional studies are experimental in character and are further subdivided into field studies (sample from an area, such as a large region or a country) and group studies (sample from a specific group, such as a specific social or ethnic group). One example was the investigation of the iodine supplementation of cooking salt to prevent cretinism in a region with iodine deficiency. On the other hand, many interventions are unsuitable for randomized intervention studies, for ethical, social or political reasons, as the exposure may be harmful to the subjects ( 17 ).

Observational epidemiological studies can be further subdivided into cohort studies (follow-up studies), case control studies, cross-sectional studies (prevalence studies), and ecological studies (correlation studies or studies with aggregated data).

In contrast, studies with only descriptive evaluation are restricted to a simple depiction of the frequency (incidence and prevalence) and distribution of a disease within a population. The objective of the description may also be the regular recording of information (monitoring, surveillance). Registry data are also suited for the description of prevalence and incidence; for example, they are used for national health reports in Germany.

In the simplest case, cohort studies involve the observation of two healthy groups of subjects over time. One group is exposed to a specific substance (for example, workers in a chemical factory) and the other is not exposed. It is recorded prospectively (into the future) how often a specific disease (such as lung cancer) occurs in the two groups ( figure 2a ). The incidence for the occurrence of the disease can be determined for both groups. Moreover, the relative risk (quotient of the incidence rates) is a very important statistical parameter which can be calculated in cohort studies. For rare types of exposure, the general population can be used as controls ( e6 ). All evaluations naturally consider the age and gender distributions in the corresponding cohorts. The objective of cohort studies is to record detailed information on the exposure and on confounding factors, such as the duration of employment, the maximum and the cumulated exposure. One well known cohort study is the British Doctors Study, which prospectively examined the effect of smoking on mortality among British doctors over a period of decades ( e7 ). Cohort studies are well suited for detecting causal connections between exposure and the development of disease. On the other hand, cohort studies often demand a great deal of time, organization, and money. So-called historical cohort studies represent a special case. In this case, all data on exposure and effect (illness) are already available at the start of the study and are analyzed retrospectively. For example, studies of this sort are used to investigate occupational forms of cancer. They are usually cheaper ( 16 ).

Graphical depiction of a prospective cohort study (simplest case [2a]) and a retrospective case control study (2b)

In case control studies, cases are compared with controls. Cases are persons who fall ill from the disease in question. Controls are persons who are not ill, but are otherwise comparable to the cases. A retrospective analysis is performed to establish to what extent persons in the case and control groups were exposed ( figure 2b ). Possible exposure factors include smoking, nutrition and pollutant load. Care should be taken that the intensity and duration of the exposure is analyzed as carefully and in as detailed a manner as possible. If it is observed that ill people are more often exposed than healthy people, it may be concluded that there is a link between the illness and the risk factor. In case control studies, the most important statistical parameter is the odds ratio. Case control studies usually require less time and fewer resources than cohort studies ( 16 ). The disadvantage of case control studies is that the incidence rate (rate of new cases) cannot be calculated. There is also a great risk of bias from the selection of the study population ("selection bias") and from faulty recall ("recall bias") (see too the article "Avoiding Bias in Observational Studies"). Table 1 presents an overview of possible types of epidemiological study ( e8 ). Table 2 summarizes the advantages and disadvantages of observational studies ( 16 ).

1 = slight; 2 = moderate; 3 = high; N/A, not applicable.

*Individual cases may deviate from this pattern.

Selecting the correct study type is an important aspect of study design (see "Study Design in Medical Research" in volume 11/2009). However, the scientific questions can only be correctly answered if the study is planned and performed at a qualitatively high level ( e9 ). It is very important to consider or even eliminate possible interfering factors (or confounders), as otherwise the result cannot be adequately interpreted. Confounders are characteristics which influence the target parameters. Although this influence is not of primary interest, it can interfere with the connection between the target parameter and the factors that are of interest. The influence of confounders can be minimized or eliminated by standardizing the procedure, stratification ( 18 ), or adjustment ( 19 ).

The decision as to which study type is suitable to answer a specific primary research question must be based not only on scientific considerations, but also on issues related to resources (personnel and finances), hospital capacity, and practicability. Many epidemiological studies can only be implemented if there is access to registry data. The demands for planning, implementation, and statistical evaluation for observational studies should be just as high for observational studies as for experimental studies. There are particularly strict requirements, with legally based regulations (such as the Medicines Act and Good Clinical Practice), for the planning, implementation, and evaluation of clinical studies. A study protocol must be prepared for both interventional and noninterventional studies ( 6 , 13 ). The study protocol must contain information on the conditions, question to be answered (objective), the methods of measurement, the implementation, organization, study population, data management, case number planning, the biometric evaluation, and the clinical relevance of the question to be answered ( 13 ).

Important and justified ethical considerations may restrict studies with optimal scientific and statistical features. A randomized intervention study under strictly controlled conditions of the effect of exposure to harmful factors (such as smoking, radiation, or a fatty diet) is not possible and not permissible for ethical reasons. Observational studies are a possible alternative to interventional studies, even though observational studies are less reliable and less easy to control ( 17 ).

A medical study should always be published in a peer reviewed journal. Depending on the study type, there are recommendations and checklists for presenting the results. For example, these may include a description of the population, the procedure for missing values and confounders, and information on statistical parameters. Recommendations and guidelines are available for clinical studies ( 14 , 20 , e10 , e11 ), for diagnostic studies ( 21 , 22 , e12 ), and for epidemiological studies ( 23 , e13 ). Since 2004, the WHO has demanded that studies should be registered in a public registry, such as www.controlled-trials.com or www.clinicaltrials.gov . This demand is supported by the International Committee of Medical Journal Editors (ICMJE) ( 24 ), which specifies that the registration of the study before inclusion of the first subject is an essential condition for the publication of the study results ( e14 ).

When specifying the study type and study design for medical studies, it is essential to collaborate with an experienced biometrician. The quality and reliability of the study can be decisively improved if all important details are planned together ( 12 , 25 ).

Acknowledgments

Translated from the original German by Rodney A. Yeates, M.A., Ph.D.

Conflict of interest statement

The authors declare that there is no conflict of interest in the sense of the International Committee of Medical Journal Editors.

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