scholarly journals A Review of Studies Leveraging Multimodal TMS-fMRI Applications in the Pathophysiology and Treatment of Schizophrenia

2021 ◽  
Vol 15 ◽  
Author(s):  
Sachin Pradeep Baliga ◽  
Urvakhsh Meherwan Mehta
Keyword(s):  
Cortical Plasticity ◽  
Low Frequency ◽  
Small Sample ◽  
Current Evidence ◽  
Short Treatment ◽  
Treatment Protocols ◽  
Auditory Verbal Hallucinations ◽  
Small Sample Sizes ◽  
Low Frequency Rtms

The current review provides an overview of the existing literature on multimodal transcranial magnetic stimulation, and functional magnetic resonance imaging (TMS/fMRI) studies in individuals with schizophrenia and discusses potential future avenues related to the same. Multimodal studies investigating pathophysiology have explored the role of abnormal thalamic reactivity and have provided further evidence supporting the hypothesis of schizophrenia as a disorder of aberrant connectivity and cortical plasticity. Among studies examining treatment, low-frequency rTMS for the management of persistent auditory verbal hallucinations (AVH) was the most studied. While multimodal TMS/fMRI studies have provided evidence of involvement of local speech-related and distal networks on stimulation of the left temporoparietal cortex, current evidence does not suggest the superiority of fMRI based neuronavigation over conventional methods or of active rTMS over sham for treatment of AVH. Apart from these, preliminary findings suggest a role of rTMS in treating deficits in neurocognition, social cognition, and self-agency. However, most of these studies have only examined medication-resistant symptoms and have methodological concerns arising from small sample sizes and short treatment protocols. That being said, combining TMS with fMRI appears to be a promising approach toward elucidating the pathophysiology of schizophrenia and could also open up a possibility toward developing personalized treatment for its persistent and debilitating symptoms.

scholarly journals Radiomics for the Diagnosis and Differentiation of Pancreatic Cystic Lesions

Diagnostics ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 505
Author(s):  
Jorge D. Machicado ◽  
Eugene J. Koay ◽  
Somashekar G. Krishna
Keyword(s):  
Predictive Accuracy ◽  
Quantitative Imaging ◽  
Standard Of Care ◽  
Small Sample ◽  
Cystic Lesions ◽  
Current Standard ◽  
Cross Sectional ◽  
Small Sample Sizes ◽  
Insight Into

Radiomics, also known as quantitative imaging or texture analysis, involves extracting a large number of features traditionally unmeasured in conventional radiological cross-sectional images and converting them into mathematical models. This review describes this approach and its use in the evaluation of pancreatic cystic lesions (PCLs). This discipline has the potential of more accurately assessing, classifying, risk stratifying, and guiding the management of PCLs. Existing studies have provided important insight into the role of radiomics in managing PCLs. Although these studies are limited by the use of retrospective design, single center data, and small sample sizes, radiomic features in combination with clinical data appear to be superior to the current standard of care in differentiating cyst type and in identifying mucinous PCLs with high-grade dysplasia. Combining radiomic features with other novel endoscopic diagnostics, including cyst fluid molecular analysis and confocal endomicroscopy, can potentially optimize the predictive accuracy of these models. There is a need for multicenter prospective studies to elucidate the role of radiomics in the management of PCLs.

scholarly journals What Role Does the Prefrontal Cortex Play in the Processing of Negative and Positive Stimuli in Adolescent Depression?

2019 ◽  
Vol 9 (5) ◽  
pp. 104 ◽  
Author(s):  
Siyabend Kaya ◽  
Ciara McCabe
Keyword(s):  
Prefrontal Cortex ◽  
Adolescent Depression ◽  
Region Of Interest ◽  
Small Sample ◽  
Symptoms Of Depression ◽  
Small Sample Sizes ◽  
Positive Stimuli ◽  
Larger Sample ◽  
Negative Stimuli

This perspective describes the contribution of the prefrontal cortex to the symptoms of depression in adolescents and specifically the processing of positive and negative information. We also discuss how the prefrontal cortex (PFC) activity and connectivity during tasks and at rest might be a biomarker for risk for depression onset in adolescents. We include some of our recent work examining not only the anticipation and consummation of positive and negative stimuli, but also effort to gain positive and avoid negative stimuli in adolescents with depression. We find, using region of interest analyses, that the PFC is blunted in those with depression compared to controls across the different phases but in a larger sample the PFC is blunted in the anticipatory phase of the study only. Taken together, in adolescents with depression there is evidence for dysfunctional PFC activity across different studies and tasks. However, the data are limited with small sample sizes and inconsistent findings. Larger longitudinal studies with more detailed assessments of symptoms across the spectrum are needed to further evaluate the role of the PFC in adolescent depression.

Penalized Binary Regression for Gene Expression Profiling

2004 ◽  
Vol 43 (05) ◽  
pp. 439-444 ◽  
Author(s):  
Michae Schimek
Keyword(s):  
Microarray Analysis ◽  
Predictive Performance ◽  
Small Sample ◽  
Probit Regression ◽  
Binary Regression ◽  
Data Set ◽  
Small Sample Sizes ◽  
Bayesian Probit Regression

Summary Objectives: A typical bioinformatics task in microarray analysis is the classification of biological samples into two alternative categories. A procedure is needed which, based on the expression levels measured, allows us to compute the probability that a new sample belongs to a certain class. Methods: For the purpose of classification the statistical approach of binary regression is considered. High-dimensionality and at the same time small sample sizes make it a challenging task. Standard logit or probit regression fails because of condition problems and poor predictive performance. The concepts of frequentist and of Bayesian penalization for binary regression are introduced. A Bayesian interpretation of the penalized log-likelihood is given. Finally the role of cross-validation for regularization and feature selection is discussed. Results: Penalization makes classical binary regression a suitable tool for microarray analysis. We illustrate penalized logit and Bayesian probit regression on a well-known data set and compare the obtained results, also with respect to published results from decision trees. Conclusions: The frequentist and the Bayesian penalization concept work equally well on the example data, however some method-specific differences can be made out. Moreover the Bayesian approach yields a quantification (posterior probabilities) of the bias due to the constraining assumptions.

scholarly journals Low-frequency rTMS over the Parieto–frontal network during a sensorimotor task: The role of absolute beta power in the sensorimotor integration

2016 ◽  
Vol 611 ◽  
pp. 1-5 ◽  
Author(s):  
Mariana Gongora ◽  
Juliana Bittencourt ◽  
Silmar Teixeira ◽  
Luis F. Basile ◽  
Fernando Pompeu ◽  
...  
Keyword(s):  
Sensorimotor Integration ◽  
Low Frequency ◽  
Beta Power ◽  
Low Frequency Rtms

scholarly journals MECHANISMS IN ENDOCRINOLOGY: Epigenetic modifications and gestational diabetes: a systematic review of published literature

2017 ◽  
Vol 176 (5) ◽  
pp. R247-R267 ◽  
Author(s):  
Gunn-Helen Moen ◽  
Christine Sommer ◽  
Rashmi B Prasad ◽  
Line Sletner ◽  
Leif Groop ◽  
...  
Keyword(s):  
Systematic Review ◽  
Gestational Diabetes ◽  
Current Knowledge ◽  
Epigenetic Modifications ◽  
Research Literature ◽  
Small Sample ◽  
Epigenetic Alterations ◽  
Search Terms ◽  
Small Sample Sizes

ObjectiveTo summarize the current knowledge on epigenetic alterations in mother and offspring subjected to gestational diabetes (GDM) and indicate future topics for research.DesignSystematic review.MethodsWe performed extensive searches in PubMed, EMBASE and Google scholar, using a combination of the search terms: GDM, gestational diabetes, epigenetic(s), methylation, histone modification, histone methylation, histone acetylation, microRNA and miRNA. Studies that compared women diagnosed with GDM and healthy controls were included. Two authors independently scanned the abstracts, and all included papers were read by at least two authors. The searches were completed on October 31st, 2016.ResultsWe identified 236 articles, of which 43 were considered relevant for this systematic review. Studies published showed that epigenetic alterations could be found in both mothers with GDM and their offspring. However, differences in methodology, diagnostic criteria for GDM and populations studied, together with a limited number of published studies and small sample sizes, preclude clear conclusions about the role of epigenetic modifications in transmitting risk from GDM mothers to their offspring.ConclusionThe current research literature suggests that GDM may have impact on epigenetic modifications in the mother and offspring. However, larger studies that include multiple cohorts of GDM patients and their offspring are needed.

scholarly journals The Current Role of Induced Endometrial Trauma (Endometrial Scratch) in Women Undergoing Infertility Treatment

2021 ◽  
Author(s):  
Mostafa Metwally ◽  
Stephen Walters ◽  
Robin Chatters
Keyword(s):  
Low Cost ◽  
Small Sample ◽  
Pregnancy Rates ◽  
Mechanical Trauma ◽  
Fertility Treatments ◽  
Current State ◽  
Randomized Controlled Studies ◽  
Endometrial Scratch ◽  
Small Sample Sizes

AbstractInduced endometrial trauma, otherwise known as endometrial scratch is a simple technique that has been rapidly adopted into clinical practice, mainly for women having IVF treatment, in an attempt to increase pregnancy rates. The introduction of endometrial scratch followed early reports of improved clinical pregnancy rates in women with repetitive implantation failure after having the procedure and follows on from evidence from animal models in the early 20th century suggesting that mechanical trauma to the endometrium can induce decidual changes. Due to the ease and low cost of the procedure, it has been rapidly adopted as an add-on to fertility treatments, in many cases where evidence is still lacking. Despite the initial publication of a large number of studies that demonstrated encouraging improvements in pregnancy rates in women who underwent this procedure, these studies were mainly limited by the small sample sizes and heterogeneity of their study populations, leading to limited validity of the evidence provided by these studies. More recently, three large randomized controlled studies have been published that paint a different picture regarding the value of this procedure. This article explores the evolution of the evidence and the current state of endometrial scratch as an adjuvant therapy for women undergoing IVF treatment.

scholarly journals Mapping influenza transmission in the ferret model to transmission in humans

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Michael G Buhnerkempe ◽  
Katelyn Gostic ◽  
Miran Park ◽  
Prianna Ahsan ◽  
Jessica A Belser ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Small Sample ◽  
Influenza Viruses ◽  
Epidemic Spread ◽  
Avian Influenza Viruses ◽  
Transmission Potential ◽  
Influenza Transmission ◽  
Small Sample Sizes

The controversy surrounding 'gain-of-function' experiments on high-consequence avian influenza viruses has highlighted the role of ferret transmission experiments in studying the transmission potential of novel influenza strains. However, the mapping between influenza transmission in ferrets and in humans is unsubstantiated. We address this gap by compiling and analyzing 240 estimates of influenza transmission in ferrets and humans. We demonstrate that estimates of ferret secondary attack rate (SAR) explain 66% of the variation in human SAR estimates at the subtype level. Further analysis shows that ferret transmission experiments have potential to identify influenza viruses of concern for epidemic spread in humans, though small sample sizes and biological uncertainties prevent definitive classification of human transmissibility. Thus, ferret transmission experiments provide valid predictions of pandemic potential of novel influenza strains, though results should continue to be corroborated by targeted virological and epidemiological research.

scholarly journals The relationship between dose and serotonin transporter occupancy of antidepressants—a systematic review

2021 ◽  
Author(s):  
Anders Sørensen ◽  
Henricus G. Ruhé ◽  
Klaus Munkholm
Keyword(s):  
Serotonin Transporter ◽  
Antidepressant Treatment ◽  
Imaging Techniques ◽  
Small Sample ◽  
Short Treatment ◽  
Predicted Values ◽  
Small Sample Sizes ◽  
The Relationship ◽  
Short Treatment Duration

AbstractBrain imaging techniques enable the visualization of serotonin transporter (SERT) occupancy as a measure of the proportion of SERT blocked by an antidepressant at a given dose. We aimed to systematically review the evidence on the relationship between antidepressant dose and SERT occupancy. We searched PubMed and Embase (last search 20 May 2021) for human in vivo, within-subject PET, or SPECT studies measuring SERT occupancy at any dose of any antidepressant with highly selective radioligands ([11C]-DASB, [123I]-ADAM, and [11C]-MADAM). We summarized and visualized the dose-occupancy relationship for antidepressants across studies, overlaying the plots with a curve based on predicted values of a standard 2-parameter Michaelis–Menten model fitted using the observed data. We included seventeen studies of 10 different SSRIs, SNRIs, and serotonin modulators comprising a total of 294 participants, involving 309 unique occupancy measures. Overall, following the Michaelis–Menten equation, SERT occupancy increased with a higher dose in a hyperbolic relationship, with occupancy increasing rapidly at lower doses and reaching a plateau at approximately 80% at the usual minimum recommended dose. All the studies were small, only a few investigated the same antidepressant, dose, and brain region, and few reported information on factors that may influence SERT occupancy. The hyperbolic dose-occupancy relationship may provide mechanistic insight of relevance to the limited clinical benefit of dose-escalation in antidepressant treatment and the potential emergence of withdrawal symptoms. The evidence is limited by non-transparent reporting, lack of standardized methods, small sample sizes, and short treatment duration. Future studies should standardize the imaging and reporting procedures, measure occupancy at lower antidepressant doses, and investigate the moderators of the dose-occupancy relationship.

scholarly journals Exercise and Nutrition Impact on Osteoporosis and Sarcopenia—The Incidence of Osteosarcopenia: A Narrative Review

Nutrients ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 4499
Author(s):  
Sousana K. Papadopoulou ◽  
Konstantinos Papadimitriou ◽  
Gavriela Voulgaridou ◽  
Evridiki Georgaki ◽  
Eudoxia Tsotidou ◽  
...  
Keyword(s):  
Older Adults ◽  
Protective Role ◽  
Scientific Data ◽  
Bone Diseases ◽  
Small Sample ◽  
Narrative Review ◽  
Prevention Of Osteoporosis ◽  
Small Sample Sizes ◽  
Meta Analyses

Osteoporosis and sarcopenia are diseases which affect the myoskeletal system and often occur in older adults. They are characterized by low bone density and loss of muscle mass and strength, factors which reduce the quality of life and mobility. Recently, apart from pharmaceutical interventions, many studies have focused on non-pharmaceutical approaches for the prevention of osteoporosis and sarcopenia with exercise and nutrition to being the most important and well studied of those. The purpose of the current narrative review is to describe the role of exercise and nutrition on prevention of osteoporosis and sarcopenia in older adults and to define the incidence of osteosarcopenia. Most of the publications which were included in this review show that resistance and endurance exercises prevent the development of osteoporosis and sarcopenia. Furthermore, protein and vitamin D intake, as well as a healthy diet, present a protective role against the development of the above bone diseases. However, current scientific data are not sufficient for reaching solid conclusions. Although the roles of exercise and nutrition on osteoporosis and sarcopenia seem to have been largely evaluated in literature over the recent years, most of the studies which have been conducted present high heterogeneity and small sample sizes. Therefore, they cannot reach final conclusions. In addition, osteosarcopenia seems to be caused by the effects of osteoporosis and sarcopenia on elderly. Larger meta-analyses and randomized controlled trials are needed designed based on strict inclusion criteria, in order to describe the exact role of exercise and nutrition on osteoporosis and sarcopenia.

scholarly journals Efficacy of Dietary Supplements in Inflammatory Bowel Disease and Related Autoimmune Diseases

Nutrients ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 2156 ◽  
Author(s):  
Priyanka Jadhav ◽  
Yan Jiang ◽  
Karolin Jarr ◽  
Cosima Layton ◽  
Judith F. Ashouri ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
Immune Response ◽  
Psoriatic Arthritis ◽  
Bowel Disease ◽  
Inflammatory Diseases ◽  
Small Sample ◽  
Therapeutic Options ◽  
Current Evidence ◽  
Inflammatory Bowel ◽  
Small Sample Sizes

The microbiome is an important contributor to a variety of fundamental aspects of human health, including host metabolism, infection, and the immune response. Gut dysbiosis has been identified as a contributor to the errant immune response in a variety of immune-mediated inflammatory diseases (IMIDs), such as inflammatory bowel disease (IBD), rheumatoid arthritis (RA), and psoriatic disease (psoriasis and psoriatic arthritis). Given this, probiotics and prebiotics have been investigated as therapeutic options in these disease states. In our review, we highlight the current evidence on prebiotics and probiotics as well as other supplements (such as fish oils, vitamin D, and curcumin) as therapies for IBD. Recommendations, however, regarding the specific use of such supplements in IBD have been lacking, particularly from professional societies, often due to study limitations related to small sample sizes and design heterogeneity. Hence, we additionally examine the literature on the use of prebiotics, probiotics, and other supplements in related IMIDs, namely RA and psoriasis/psoriatic arthritis, as these diseases share many approved therapeutic options with IBD. Based on these combined findings, we offer additional evidence that may help guide clinicians in their treatment of patients with IBD (and other IMIDs) and provide recommendations on potential next steps in therapeutic research in this area.

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