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1.
Bioinformatics ; 40(4)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38569889

RESUMO

SUMMARY: Segmentation of neural somata is a crucial and usually the most time-consuming step in the analysis of optical functional imaging of neuronal microcircuits. In recent years, multiple auto-segmentation tools have been developed to improve the speed and consistency of the segmentation process, mostly, using deep learning approaches. Current segmentation tools, while advanced, still encounter challenges in producing accurate segmentation results, especially in datasets with a low signal-to-noise ratio. This has led to a reliance on manual segmentation techniques. However, manual methods, while customized to specific laboratory protocols, can introduce variability due to individual differences in interpretation, potentially affecting dataset consistency across studies. In response to this challenge, we present ViNe-Seg: a deep-learning-based semi-automatic segmentation tool that offers (i) detection of visible neurons, irrespective of their activity status; (ii) the ability to perform segmentation during an ongoing experiment; (iii) a user-friendly graphical interface that facilitates expert supervision, ensuring precise identification of Regions of Interest; (iv) an array of segmentation models with the option of training custom models and sharing them with the community; and (v) seamless integration of subsequent analysis steps. AVAILABILITY AND IMPLEMENTATION: ViNe-Seg code and documentation are publicly available at https://github.com/NiRuff/ViNe-Seg and can be installed from https://pypi.org/project/ViNeSeg/.

2.
J Clin Med ; 11(19)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36233463

RESUMO

To identify potential genetic causes for Mayer-Rokitansky-Küster-Hauser syndrome (MRKH), we analyzed blood and rudimentary uterine tissue of 5 MRKH discordant monozygotic twin pairs. Assuming that a variant solely identified in the affected twin or affected tissue could cause the phenotype, we identified a mosaic variant in ACTR3B with high allele frequency in the affected tissue, low allele frequency in the blood of the affected twin, and almost absent in blood of the unaffected twin. Focusing on MRKH candidate genes, we detected a pathogenic variant in GREB1L in one twin pair and their unaffected mother showing a reduced phenotypic penetrance. Furthermore, two variants of unknown clinical significance in PAX8 and WNT9B were identified. In addition, we conducted transcriptome analysis of affected tissue and observed perturbations largely similar to those in sporadic cases. These shared transcriptional changes were enriched for terms associated with estrogen and its receptors pointing at a role of estrogen in MRKH pathology. Our genome sequencing approach of blood and uterine tissue of discordant twins is the most extensive study performed on twins discordant for MRKH so far. As no clear pathogenic differences were detected, research to evaluate other regulatory layers are required to better understand the complex etiology of MRKH.

3.
Front Cell Dev Biol ; 8: 572281, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072755

RESUMO

The Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome (OMIM 277000) is characterized by agenesis of the uterus and upper part of the vagina in females with normal ovarian function. While genetic causes have been identified for a small subset of patients and epigenetic mechanisms presumably contribute to the pathogenic unfolding, too, the etiology of the syndrome has remained largely enigmatic. A comprehensive understanding of gene activity in the context of the disease is crucial to identify etiological components and their potential interplay. So far, this understanding is lacking, primarily due to the scarcity of samples and suitable tissue. In order to close this gap, we profiled endometrial tissue of uterus rudiments in a large cohort of MRKH patients using RNA-seq and thereby provide a genome-wide view on the altered transcription landscape of the MRKH syndrome. Differential and co-expression analyses of the data identified cellular processes and candidate genes that converge on a core network of interconnected regulators that emerge as pivotal for the perturbed expression space. With these results and browsable access to the rich data through an online tool we seek to accelerate research to unravel the underlying biology of the syndrome.

4.
Depress Anxiety ; 35(10): 925-934, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30099829

RESUMO

BACKGROUND: Glucocorticoids reduce phobic fear in patients with anxiety disorders. Although the neurobiology of anxiety disorders is not fully understood, convergent structural and functional neuroimaging studies have identified abnormalities in various brain regions, including those in the salience network (SN) and default mode network (DMN). Here, we examine the effects of glucocorticoid administration on SN and DMN activity during the processing of phobic stimuli. METHODS: We use functional magnetic resonance imaging to record brain activity in 24 female patients with spider phobia who were administered either 20 mg of cortisol or placebo while viewing pictures of spiders. Fourteen healthy female participants were tested with the same task but without substance administration. Independent component analysis (ICA) performed during stimulus encoding identified the SN and DMN as exhibiting synchronized activation in diverse brain regions; thus, we examined the effects of cortisol on these networks. Furthermore, participants had to rate their level of fear at various time points. RESULTS: Glucocorticoids reduced phobic fear in patients with spider phobia. The ICA performed during stimulus encoding revealed that activity in the SN and DMN was reduced in placebo-treated patients versus healthy controls. Brain activity in the SN, but not the DMN, was altered in cortisol- versus placebo-treated patients to a level that was similar to that observed in healthy controls. CONCLUSIONS: Activity in both the SN and DMN was reduced in patients with spider phobia. Cortisol administration altered the SN activity to a level that was comparable to that found in healthy controls. This alteration in SN activity might reflect the fear-reducing effects of glucocorticoids in phobia.


Assuntos
Encéfalo/efeitos dos fármacos , Medo/efeitos dos fármacos , Glucocorticoides/farmacologia , Hidrocortisona/farmacologia , Vias Neurais/efeitos dos fármacos , Transtornos Fóbicos/diagnóstico por imagem , Adolescente , Adulto , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Método Duplo-Cego , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Transtornos Fóbicos/fisiopatologia , Aranhas , Adulto Jovem
5.
Oncotarget ; 6(41): 43420-37, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26486078

RESUMO

Secreted proteins could modulate the interaction between tumor, stroma and immune cells within the tumor microenvironment thereby mounting an immunosuppressive tumor microenvironment. In order to determine the secretome-mediated, von Hippel Lindau (VHL)-regulated cross-talk between tumor cells and T lymphocytes peripheral blood mononuclear cells (PBMC) from healthy donors were either cultured in conditioned media obtained from normoxic and hypoxic human VHL-deficient renal cell carcinoma (RCC) cell line (786-0VHL-) and its wild type (wt) VHL-transfected counterpart (786-0VHL+) or directly co-cultured with both cell lines. An increased T cell proliferation was detected in the presence of 786-0VHL+-conditioned medium. By applying a quantitative proteomic-based approach using differential gel electrophoresis followed by mass spectrometry fourteen proteins were identified to be differentially expressed within the secretome of 786-0VHL- cells when compared to that of 786-0VHL+ cells. All proteins identified were involved in multiple tumor-associated biological functions including immune responses. Functional studies on manganese superoxide dismutase 2 (MnSOD2) demonstrated that it was a regulator of T cell activation-induced oxidative signaling and cell death. Direct effects of soluble MnSOD2 on the growth properties and interleukin 2 (IL-2) secretion of T cells could be demonstrated underlining the critical role of extracellular MnSOD2 levels for T cell proliferation and activation.


Assuntos
Carcinoma de Células Renais/metabolismo , Neoplasias Renais/metabolismo , Evasão Tumoral/imunologia , Microambiente Tumoral/imunologia , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Western Blotting , Carcinoma de Células Renais/imunologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Técnicas de Cocultura , Eletroforese em Gel Bidimensional , Humanos , Neoplasias Renais/imunologia , Ativação Linfocitária/imunologia , Reação em Cadeia da Polimerase , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Superóxido Dismutase/metabolismo , Subpopulações de Linfócitos T/imunologia , Linfócitos T/imunologia , Transfecção
6.
Nature ; 514(7523): 494-7, 2014 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-25141181

RESUMO

Modern strains of Mycobacterium tuberculosis from the Americas are closely related to those from Europe, supporting the assumption that human tuberculosis was introduced post-contact. This notion, however, is incompatible with archaeological evidence of pre-contact tuberculosis in the New World. Comparative genomics of modern isolates suggests that M. tuberculosis attained its worldwide distribution following human dispersals out of Africa during the Pleistocene epoch, although this has yet to be confirmed with ancient calibration points. Here we present three 1,000-year-old mycobacterial genomes from Peruvian human skeletons, revealing that a member of the M. tuberculosis complex caused human disease before contact. The ancient strains are distinct from known human-adapted forms and are most closely related to those adapted to seals and sea lions. Two independent dating approaches suggest a most recent common ancestor for the M. tuberculosis complex less than 6,000 years ago, which supports a Holocene dispersal of the disease. Our results implicate sea mammals as having played a role in transmitting the disease to humans across the ocean.


Assuntos
Caniformia/microbiologia , Genoma Bacteriano/genética , Mycobacterium tuberculosis/genética , Tuberculose/história , Tuberculose/microbiologia , Zoonoses/história , Zoonoses/microbiologia , Animais , Osso e Ossos/microbiologia , Europa (Continente)/etnologia , Genômica , História Antiga , Migração Humana/história , Humanos , Peru , Filogenia , Tuberculose/transmissão , Zoonoses/transmissão
7.
Methods Enzymol ; 531: 465-85, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24060133

RESUMO

Metagenomics, the study of microbes in the environment using DNA sequencing, depends upon dedicated software tools for processing and analyzing very large sequencing datasets. One such tool is MEGAN (MEtaGenome ANalyzer), which can be used to interactively analyze and compare metagenomic and metatranscriptomic data, both taxonomically and functionally. To perform a taxonomic analysis, the program places the reads onto the NCBI taxonomy, while functional analysis is performed by mapping reads to the SEED, COG, and KEGG classifications. Samples can be compared taxonomically and functionally, using a wide range of different charting and visualization techniques. PCoA analysis and clustering methods allow high-level comparison of large numbers of samples. Different attributes of the samples can be captured and used within analysis. The program supports various input formats for loading data and can export analysis results in different text-based and graphical formats. The program is designed to work with very large samples containing many millions of reads. It is written in Java and installers for the three major computer operating systems are available from http://www-ab.informatik.uni-tuebingen.de.


Assuntos
RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação , Software , Algoritmos , Bases de Dados Genéticas , Metagenômica , Consórcios Microbianos/genética , Análise de Sequência de DNA
8.
Curr Hypertens Rep ; 15(5): 444-52, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23897423

RESUMO

There is growing concern about elevated blood pressure in children and adolescents, because of its association with the obesity epidemic. Moreover, cardiovascular function and blood pressure level are determined in childhood and track into adulthood. Primary hypertension in childhood is defined by persistent blood pressure values ≥ the 95th percentile and without a secondary cause. Preventable risk factors for elevated blood pressure in childhood are overweight, dietary habits, salt intake, sedentary lifestyle, poor sleep quality and passive smoking, whereas non-preventable risk factors include race, gender, genetic background, low birth weight, prematurity, and socioeconomic inequalities. Several different pathways are implicated in the development of primary hypertension, including obesity, insulin resistance, activation of the sympathetic nervous system, alterations in sodium homeostasis, renin-angiotensin system and altered vascular function. Prevention of adult cardiovascular disease should begin in childhood by regularly screening for high blood pressure, counseling for healthy lifestyle and avoiding preventable risk factors.


Assuntos
Hipertensão/etiologia , Pressão Sanguínea , Determinação da Pressão Arterial , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Criança , Humanos , Fatores de Risco , Sódio na Dieta/efeitos adversos
9.
Genome Res ; 21(9): 1552-60, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21690186

RESUMO

A major challenge in the analysis of environmental sequences is data integration. The question is how to analyze different types of data in a unified approach, addressing both the taxonomic and functional aspects. To facilitate such analyses, we have substantially extended MEGAN, a widely used taxonomic analysis program. The new program, MEGAN4, provides an integrated approach to the taxonomic and functional analysis of metagenomic, metatranscriptomic, metaproteomic, and rRNA data. While taxonomic analysis is performed based on the NCBI taxonomy, functional analysis is performed using the SEED classification of subsystems and functional roles or the KEGG classification of pathways and enzymes. A number of examples illustrate how such analyses can be performed, and show that one can also import and compare classification results obtained using others' tools. MEGAN4 is freely available for academic purposes, and installers for all three major operating systems can be downloaded from www-ab.informatik.uni-tuebingen.de/software/megan.


Assuntos
Metagenômica , Software , Classificação , Metagenoma/genética , Proteômica , RNA Ribossômico 16S/genética , Transcriptoma
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