Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
1.
medRxiv ; 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38562783

ABSTRACT

Background: Amyloid beta protein (Aß) is a treatment target in Alzheimer's Disease (AD). Lowering production of its parent protein, APP, has benefits in preclinical models. Posiphen binds to an iron-responsive element in APP mRNA and decreases translation of APP and Aß. To augment human data for Posiphen, we evaluated safety, tolerability and pharmacokinetic and pharmacodynamic (PD) effects on Aß metabolism using Stable Isotope Labeling Kinetic (SILK) analysis. Methods: Double-blind phase 1b randomized ascending dose clinical trial, at five sites, under an IRB-approved protocol. Participants with mild cognitive impairment or mild AD (Early AD) with positive CSF biomarkers were randomized (within each dose arm) to Posiphen or placebo. Pretreatment assessment included lumbar puncture for CSF. Participants took Posiphen or placebo for 21-23 days, then underwent CSF catheter placement, intravenous infusion of 13C6-leucine, and CSF sampling for 36 hours. Safety and tolerability were assessed through participant reports, EKG and laboratory tests. CSF SILK analysis measured Aß40, 38 and 42 with immunoprecipitation-mass spectrometry. Baseline and day 21 CSF APP, Aß and other biomarkers were measured with immunoassays. The Mini-Mental State Exam and ADAS-cog12 were given at baseline and day 21. Results: From June 2017 to December 2021, 19 participants were enrolled, in dose cohorts (6 active: 2 placebo) of 60 mg once/day and 60 mg twice/day; 1 participant was enrolled and completed 60 mg three times/day. 10 active drug and 5 placebo participants completed all study procedures. Posiphen was safe and well-tolerated. 8 participants had headaches related to CSF catheterization; 5 needed blood patches. Prespecified SILK analyses of Fractional Synthesis Rate (FSR) for CSF Aß40 showed no significant overall or dose-dependent effects of Posiphen vs. placebo. Comprehensive multiparameter modeling of APP kinetics supported dose-dependent lowering of APP production by Posiphen. Cognitive measures and CSF biomarkers did not change significantly from baseline to 21 days in Posiphen vs placebo groups. Conclusions: Posiphen was safe and well-tolerated in Early AD. A multicenter SILK study was feasible. Findings are limited by small sample size but provide additional supportive safety and PK data. Comprehensive modeling of biomarker dynamics using SILK data may reveal subtle drug effects. Trial registration: NCT02925650 on clinicaltrials.gov.

2.
mSystems ; 9(3): e0125723, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38349131

ABSTRACT

Limosilactobacillus reuteri, a probiotic microbe instrumental to human health and sustainable food production, adapts to diverse environmental shifts via dynamic gene expression. We applied the independent component analysis (ICA) to 117 RNA-seq data sets to decode its transcriptional regulatory network (TRN), identifying 35 distinct signals that modulate specific gene sets. Our findings indicate that the ICA provides a qualitative advancement and captures nuanced relationships within gene clusters that other methods may miss. This study uncovers the fundamental properties of L. reuteri's TRN and deepens our understanding of its arginine metabolism and the co-regulation of riboflavin metabolism and fatty acid conversion. It also sheds light on conditions that regulate genes within a specific biosynthetic gene cluster and allows for the speculation of the potential role of isoprenoid biosynthesis in L. reuteri's adaptive response to environmental changes. By integrating transcriptomics and machine learning, we provide a system-level understanding of L. reuteri's response mechanism to environmental fluctuations, thus setting the stage for modeling the probiotic transcriptome for applications in microbial food production. IMPORTANCE: We have studied Limosilactobacillus reuteri, a beneficial probiotic microbe that plays a significant role in our health and production of sustainable foods, a type of foods that are nutritionally dense and healthier and have low-carbon emissions compared to traditional foods. Similar to how humans adapt their lifestyles to different environments, this microbe adjusts its behavior by modulating the expression of genes. We applied machine learning to analyze large-scale data sets on how these genes behave across diverse conditions. From this, we identified 35 unique patterns demonstrating how L. reuteri adjusts its genes based on 50 unique environmental conditions (such as various sugars, salts, microbial cocultures, human milk, and fruit juice). This research helps us understand better how L. reuteri functions, especially in processes like breaking down certain nutrients and adapting to stressful changes. More importantly, with our findings, we become closer to using this knowledge to improve how we produce more sustainable and healthier foods with the help of microbes.


Subject(s)
Limosilactobacillus reuteri , Probiotics , Humans , Limosilactobacillus reuteri/genetics , Gene Expression Profiling , Transcriptome/genetics , Machine Learning
3.
Childs Nerv Syst ; 40(2): 555-561, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37796295

ABSTRACT

INTRODUCTION: Polymorphous low grade neuroepithelial tumor of the young (PLNTY) is a newly described epileptogenic tumor first reported by Jason. T. Huse et al. in 2016. Only a very few cases have been reported so far and has been recently incorporated in the World Health Organization (WHO) Central Nervous System Classification of tumours, 5th edition, 2021. Here we report a rare case of PLNTY which closely resembles DNET (Dysembryoplastic neuroepithelial tumor) with plenty of interesting findings which would otherwise go unnoticed resulting in a nonspecific or misclassified diagnosis. CASE REPORT: A 12 year old boy presented to the Neurosurgery OPD with seizures for the past five years and was given multiple antiepileptics for the same. Magnetic resonance imaging (MRI) showed a well-defined lobulated cortical mass with T1 hypo intensity and T2 hyperintensity in the left temporal lobe measuring 2.1 × 2 × 1.3 cm suggesting a DNET. Left temporal craniotomy and excision of the lesion was done. Frozen section showed features of a low grade glial neoplasm. Routine sections demonstrated polymorphous findings including oligodendroglia like features, neuronal nuclear pleomorphism, spindled astroglial elements, perivascular rosettes, calcification, and vascular mineralization. By immunohistochemistry (IHC), the tumor cells were diffusely positive for GFAP and CD34.Ki67 labelling index was low. A final diagnosis of PLNTY was made based on the above findings. The child has been epilepsy free since the past one-month post-surgery and is on follow up. DISCUSSION/CONCLUSION: PLNTY is a newly discovered distinct pediatric low grade glial neoplasm which was earlier grouped into nonspecific forms of DNET. It is characterized morphologically and molecularly by the presence of oligodendroglial component, CD34 expression, BRAFV600E mutation and alterations in the MAP kinase pathway. They are known to behave in a low-grade fashion amenable to control by excision with occasional cases of recurrence reported. It is important to recognize and report similar tumors to determine the long-term risk of recurrence and create a more complete understanding on their radiology and molecular genetics.


Subject(s)
Brain Neoplasms , Epilepsy , Glioma , Neoplasms, Neuroepithelial , Male , Humans , Child , Neoplasms, Neuroepithelial/diagnostic imaging , Neoplasms, Neuroepithelial/surgery , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/surgery , Seizures
4.
Am J Forensic Med Pathol ; 44(4): 293-302, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38019949

ABSTRACT

ABSTRACT: A cross-sectional study of the wound age estimation from the forensic skin wound samples was performed immunohistochemically with a sample size of 40 (n = 40). The samples were segregated according to the appropriate stages of wound healing with the help of hematoxylin-eosin staining. Later, they were subjected to immunohistochemistry staining with anti-AQP3 antibody. Quantification of the expression of AQP3 in the injured and uninjured formalin-fixed skin tissues was done semiquantitatively and manually under 400× magnifications. The AQP3-positive cells were correlated with the duration of injury, and the results were statistically analyzed. More AQP3 expressions were found in the proliferative phase than the inflammatory and maturation phase of wound healing. Neither the diversity in age group nor the sex differentiation showed any specific correlation with the expression of keratinocytic aquaporin cells. Likewise, parameters such as the type of injury, mode of injury, and the postmortem interval also did not show any significant relationship with the expression of the aquaporin positivity. Thus, it is revealed that skin wounds between 5 and 10 days expressed aquaporin cell numbers of more than 300. Hence AQP3 estimation helps in determining the time since injury with a more accuracy.


Subject(s)
Aquaporin 3 , Aquaporins , Humans , Immunohistochemistry , Cross-Sectional Studies , Aquaporin 3/metabolism , Skin , Aquaporins/metabolism
5.
Cureus ; 15(7): e42352, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37621817

ABSTRACT

Introduction Despite the growing advances in molecular research and therapeutics, gliomas continue to be highly invasive and progressive tumors. There is still a need for the development of reliable prognostic biomarkers for effective therapeutic intervention. This study aims to investigate the extent of immunosuppression in glial tumors by analyzing the clinical significance of the expressions of PD-1 and FOXP3 in gliomas. Methods This is a retrospective study from 52 glioma patients who underwent surgery. Immunohistochemistry (IHC) for PD-1 and FOXP3 was performed on paraffin-embedded tissue sections manually and their expressions were noted. Data on IDH1 mutational status and mitotic index was collected and statistically analyzed. Results Immunohistochemical analysis showed that out of 52 cases, 71.15% (37/52) demonstrated cytoplasmic positivity for PD-1 and 73.1% (38/52) of the cases for nuclear FOXP3 expression. Statistical analysis suggested that elevated PD-1 and FOXP3 expressions were significantly correlated with tumor grade and increased mitotic index (P<0.05 for both the markers). Conclusion Concurrent use of checkpoint inhibitors along with other treatment modalities is being studied in a variety of solid tumors. Expressions of negative immune regulators like PD-1 and Foxp3 can pave way for a better understanding of the extent of immunosuppression in the glial tumor environment, which is imperative to formulate new therapeutic approaches.

6.
Elife ; 112022 10 21.
Article in English | MEDLINE | ID: mdl-36269057

ABSTRACT

Elucidating the design principles of regulatory networks driving cellular decision-making has fundamental implications in mapping and eventually controlling cell-fate decisions. Despite being complex, these regulatory networks often only give rise to a few phenotypes. Previously, we identified two 'teams' of nodes in a small cell lung cancer regulatory network that constrained the phenotypic repertoire and aligned strongly with the dominant phenotypes obtained from network simulations (Chauhan et al., 2021). However, it remained elusive whether these 'teams' exist in other networks, and how do they shape the phenotypic landscape. Here, we demonstrate that five different networks of varying sizes governing epithelial-mesenchymal plasticity comprised of two 'teams' of players - one comprised of canonical drivers of epithelial phenotype and the other containing the mesenchymal inducers. These 'teams' are specific to the topology of these regulatory networks and orchestrate a bimodal phenotypic landscape with the epithelial and mesenchymal phenotypes being more frequent and dynamically robust to perturbations, relative to the intermediary/hybrid epithelial/mesenchymal ones. Our analysis reveals that network topology alone can contain information about corresponding phenotypic distributions, thus obviating the need to simulate them. We propose 'teams' of nodes as a network design principle that can drive cell-fate canalization in diverse decision-making processes.


Subject(s)
Epithelial-Mesenchymal Transition , Gene Regulatory Networks , Epithelial-Mesenchymal Transition/genetics , Phenotype , Cell Differentiation
7.
Biochem Mol Biol Educ ; 50(2): 237-245, 2022 03.
Article in English | MEDLINE | ID: mdl-35089641

ABSTRACT

Undergraduate research is an important component of a B.Tech. Biotechnology program. In the present study, a customizable approach designed with open-source bioinformatics tools and databases was introduced to predict siRNAs for ZIKV therapeutics. With minimal prior exposure to bioinformatics, this workflow can be executed with detailed steps as demonstrated in this paper. All software, databases, and servers used in this research are open-source, allowing this project-based learning methodology to be implemented remotely as well. The workflow designed in the present study is flexible and customizable according to the mentor and student's requirements.


Subject(s)
Zika Virus Infection , Zika Virus , Computational Biology/methods , Humans , RNA, Small Interfering/chemistry , RNA, Small Interfering/genetics , RNA, Small Interfering/therapeutic use , Software , Students , Zika Virus/genetics
8.
Am J Med Genet A ; 185(6): 1767-1775, 2021 06.
Article in English | MEDLINE | ID: mdl-33729670

ABSTRACT

Specialty centers improve care for patients with Down syndrome. The cohort of adults with Down syndrome is increasing, but the capacity for specialty centers to meet their medical care needs is unknown. Electronic survey of staff of specialty clinics for adults with Down syndrome was conducted. Review of online clinic listings, and calculation of the number of adults with Down syndrome were performed. Analysis identified the percent of adults with Down syndrome who could have their medical care needs met in a current specialty clinic. Fourteen specialty clinics report providing care for 4038 adults with Down syndrome. Respondents reported gaps in care including: limitations of existing clinics, need for additional clinics, and knowledgeable health professionals in Down syndrome. Survey-respondent clinic capacity would meet needs of 3% of adults with Down syndrome. Twenty-five clinics for adults with Down syndrome were listed online with capacity to care for 6517 adults with Down syndrome meeting the needs of 5% of the population. Additional clinic capacity is needed to meet the needs of adults with Down syndrome. Survey of existing clinics provides guidance to create additional clinics, including: must-have team members, current sources of clinic financial support, and gaps in current clinical care.


Subject(s)
Ambulatory Care Facilities , Down Syndrome/epidemiology , Health Services Accessibility , Adult , Cohort Studies , Down Syndrome/genetics , Down Syndrome/therapy , Female , Health Services Research/trends , Humans , Male , Patient Care , Surveys and Questionnaires
11.
Cureus ; 12(3): e7369, 2020 Mar 22.
Article in English | MEDLINE | ID: mdl-32328381

ABSTRACT

Background Gastrointestinal stromal tumors (GIST) are the most common mesenchymal neoplasms in the gastrointestinal (GI) tract. The mutation of C-KIT is considered to be the crucial step in the tumorigenesis. Targeted therapies are being developed focusing these mutations. Various exon mutations of GIST responded in varied patterns to this targeted therapy. This study was carried out to evaluate the C-KIT exon 11, exon 9 and BRAF V600E mutations among GIST specimens. Methods This retrospective study was carried out among 20 DNA extracted specimens from paraffin blocks of GIST received in our tertiary teaching institution for a period of three years. DNA sequencing was carried out for mutational analyses on C-KIT exon 9, C-KIT exon 11 and BRAF V600E genes using Sanger sequencing. Results Histologically, majority of the tumors had spindle cell morphology. About 19 cases were positive for CD117. The analysis of type of mutations showed that three cases carried Exon 11 and three cases carried Exon 9 mutations. BRAF V600E mutation was seen in one case. Conclusion It is essential to conduct molecular studies on GISTs in order to get a clear understanding of the pathogenesis and behavior pattern. This will also help in designing targeted therapies and assessing recurrence. With the advent of rapidly evolving personalized therapy, the evaluation of genetic mutations is essential for diagnosis and prognostic value.

13.
Neurology ; 79(9): 915-21, 2012 Aug 28.
Article in English | MEDLINE | ID: mdl-22895581

ABSTRACT

OBJECTIVE: It has been hypothesized that individuals without dementia with Alzheimer disease (AD) neuropathology may be in the preclinical stages of dementia and could be experiencing subtle cognitive decline. The purpose of this study was to compare longitudinal cognitive performance in oldest-old individuals without dementia with and without AD neuropathology. METHODS: The study included 58 individuals without dementia from The 90+ Autopsy Study, a population-based study of aging and dementia in individuals aged 90 and older. Participants had neurologic and neuropsychological testing every 6 months with an average of 3 years of follow-up. We compared the trajectory of cognitive performance on the Modified Mini-Mental State Examination (3MS) and the California Verbal Learning Test II (CVLT) by level of AD neuropathology. Based on Consortium to Establish a Registry for Alzheimer's Disease plaque staging, individuals were categorized as having low (none or sparse) or high (moderate or frequent) plaques. Based on Braak and Braak staging, participants were classified as having low (stages I-III) or high (IV-VI) tangles. RESULTS: No significant differences were found in 3MS or CVLT cognitive performance over time based on plaque or tangle staging. Both high and low pathology groups showed modest improvements on the 3MS and CVLT consistent with learning effects. CONCLUSIONS: AD neuropathology at autopsy is not associated with the trajectory of cognitive performance in the 3 years before death in oldest-old without dementia. Despite the presence of AD neuropathology at death, oldest-old without dementia display learning effects on cognitive tests. Further research is necessary to understand factors other than AD neuropathology that may affect cognition in the oldest-old.


Subject(s)
Aged, 80 and over/physiology , Aged, 80 and over/psychology , Alzheimer Disease/pathology , Alzheimer Disease/psychology , Cognition/physiology , Psychomotor Performance/physiology , Autopsy , Dementia/pathology , Dementia/psychology , Diagnostic and Statistical Manual of Mental Disorders , Educational Status , Female , Humans , Longitudinal Studies , Male , Models, Statistical , Neurofibrillary Tangles/pathology , Neuropsychological Tests , Plaque, Amyloid/pathology , Sex Factors , Verbal Learning
14.
Maturitas ; 70(2): 164-8, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21831546

ABSTRACT

The "oldest-old" comprise the fastest growing segment of the population in much of the world. Rates of dementia are extremely high in this age group and will present a major public health burden as the numbers of these individuals quadruple by the middle of the century. Studies in this age group are rare and frequently have small numbers of participants. In research studies and the clinic, the diagnosis of dementia and determination of the etiology of the disorder are challenging. In this review, we include some of our experiences in a population-based longitudinal investigation, The 90+ Study. Oldest-old individuals are more likely to suffer from medical comorbidities and have high rates of sensory loss, psychoactive medication usage, frailty and fatigue. Moreover, social and cultural expectations affect the reporting and interpretation of behavioral changes. These and other factors make it difficult to determine the relative contributions of cognitive losses and non-cognitive losses in the development of functional disability. Contributing further to the complexities of diagnosis, current research suggests that dementia in the oldest-old, compared to younger people, is more likely to be related to mixed disease pathologies. Frequent cerebral neuropathologies include Alzheimer's disease neurodegeneration, small and large vessel vascular disease, and hippocampal sclerosis. More research is necessary in the oldest-old to better understand the etiologies of dementia in this age group, and factors that may affect the expression of disease as we age.


Subject(s)
Activities of Daily Living , Dementia/diagnosis , Dementia/etiology , Aged, 80 and over , Dementia/pathology , Diagnosis, Differential , Hippocampus/pathology , Humans , Longitudinal Studies , Neurodegenerative Diseases/diagnosis , Sclerosis , Vascular Diseases/diagnosis
SELECTION OF CITATIONS
SEARCH DETAIL
...