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1.
bioRxiv ; 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38014183

RESUMO

Integrin signaling plays important roles in development and disease. An adhesion signaling network called the integrin adhesome has been principally defined using bioinformatics and proteomics. To date, the adhesome has not been studied using integrated proteomic and genetic approaches. Here, proteomic studies in C. elegans identified physical associations between the RPM-1 ubiquitin ligase signaling hub and numerous adhesome components including Talin, Kindlin and beta-integrin. C. elegans RPM-1 is orthologous to human MYCBP2, a prominent player in nervous system development associated with a neurodevelopmental disorder. Using neuron-specific, CRISPR loss-of-function strategies, we show that core adhesome components affect axon development and interact genetically with RPM-1. Mechanistically, Talin opposes RPM-1 in a functional 'tug-of-war' on growth cones that is required for accurate axon termination. Thus, our findings orthogonally validate the adhesome via multi-component genetic and physical interfaces with a key neuronal signaling hub and identify new links between the adhesome and brain disorders.

2.
CBE Life Sci Educ ; 21(3): ar57, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35998160

RESUMO

Community colleges expand access to higher education and play a key role in efforts to increase and diversify the future science, technology, engineering, and mathematics (STEM) workforce. While community colleges increase access to higher education and millions of students attend them for some portion of their education, the experiences of transfer students remain relatively understudied. Transferring during an academic journey can compound the barriers that students already face when pursuing a STEM degree. This study uses Schlossberg's model for analyzing human adaptation to transition to understand how STEM community college transfer students navigate and adapt to the 4-year university. Five semistructured focus groups were conducted with STEM community college transfer students attending an urban university. Analysis of the focus groups resulted in a new model: the amended model of adaptation to transfer transition, or AMATT, which illustrates various factors that played a role in STEM community college transfer students' adaptation a university. Analyses illumined two broad pathways that students tend to diverge into during their transitions-thriving or simply surviving. This work provides a framework for understanding factors influencing the transfer process and ideally will inform institutions and students as they consider maximal transfer student success.


Assuntos
Engenharia , Estudantes , Engenharia/educação , Humanos , Matemática , Tecnologia/educação , Universidades
3.
PLoS One ; 17(1): e0262556, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35025964

RESUMO

Bacteriophages exhibit a vast spectrum of relatedness and there is increasing evidence of close genomic relationships independent of host genus. The variability in phage similarity at the nucleotide, amino acid, and gene content levels confounds attempts at quantifying phage relatedness, especially as more novel phages are isolated. This study describes three highly similar novel Arthrobacter globiformis phages-Powerpuff, Lego, and YesChef-which were assigned to Cluster AZ using a nucleotide-based clustering parameter. Phages in Cluster AZ, Microbacterium Cluster EH, and the former Microbacterium singleton Zeta1847 exhibited low nucleotide similarity. However, their gene content similarity was in excess of the recently adopted Microbacterium clustering parameter, which ultimately resulted in the reassignment of Zeta1847 to Cluster EH. This finding further highlights the importance of using multiple metrics to capture phage relatedness. Additionally, Clusters AZ and EH phages encode a shared integrase indicative of a lysogenic life cycle. In the first experimental verification of a Cluster AZ phage's life cycle, we show that phage Powerpuff is a true temperate phage. It forms stable lysogens that exhibit immunity to superinfection by related phages, despite lacking identifiable repressors typically required for lysogenic maintenance and superinfection immunity. The ability of phage Powerpuff to undergo and maintain lysogeny suggests that other closely related phages may be temperate as well. Our findings provide additional evidence of significant shared phage genomic content spanning multiple actinobacterial host genera and demonstrate the continued need for verification and characterization of life cycles in newly isolated phages.


Assuntos
Arthrobacter/virologia , Bacteriófagos/genética , Microbacterium/virologia , Arthrobacter/genética , Bacteriófagos/classificação , Análise por Conglomerados , Variação Genética , Genoma Viral , Genômica , Microbacterium/genética , Filogenia
4.
IDCases ; 22: e00966, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33209583

RESUMO

We present the case of a 59-year-old Midwestern farmer who presented with altered mental status, dysarthria, urinary incontinence, and a right-sided L5 dermatomal rash; he had recently received a course of oral corticosteroids for treatment of radicular low back pain. Lumbar puncture revealed the presence of varicella zoster virus (VZV) and IgM antibodies against a California-group encephalitis virus, later confirmed as Jamestown Canyon virus (JCV). Unfortunately, the patient's health declined despite aggressive treatment, developing progressive subarachnoid hemorrhage. He died after withdrawal of supportive care following 3 weeks in the intensive care unit. To our knowledge, this is the first documented case of encephalitis associated with coinfection by VZV and JCV. While the relative contributions of these viral pathogens to the patient's illness are difficult to ascertain, the clinical features of this case are consistent with co-pathogenesis, possibly driven by antecedent corticosteroid use. This case highlights the emerging role of viral coinfections in the etiology of viral illnesses.

5.
J Immunol ; 197(1): 97-107, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27217583

RESUMO

Commensal microbiota are critical for the development of local immune responses. In this article, we show that gut microbiota can regulate CD4 T cell polarization during pulmonary fungal infections. Vancomycin drinking water significantly decreased lung Th17 cell numbers during acute infection, demonstrating that Gram-positive commensals contribute to systemic inflammation. We next tested a role for RegIIIγ, an IL-22-inducible antimicrobial protein with specificity for Gram-positive bacteria. Following infection, increased accumulation of Th17 cells in the lungs of RegIIIγ(-/-) and Il22(-/-) mice was associated with intestinal segmented filamentous bacteria (SFB) colonization. Although gastrointestinal delivery of rRegIIIγ decreased lung inflammatory gene expression and protected Il22(-/-) mice from weight loss during infection, it had no direct effect on SFB colonization, fungal clearance, or lung Th17 immunity. We further show that vancomycin only decreased lung IL-17 production in mice colonized with SFB. To determine the link between gut microbiota and lung immunity, serum-transfer experiments revealed that IL-1R ligands increase the accumulation of lung Th17 cells. These data suggest that intestinal microbiota, including SFB, can regulate pulmonary adaptive immune responses.


Assuntos
Aspergilose/imunologia , Aspergillus fumigatus/imunologia , Microbioma Gastrointestinal/imunologia , Bactérias Gram-Positivas/imunologia , Pulmão/imunologia , Células Th17/imunologia , Animais , Antibacterianos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Células Cultivadas , Imunidade/efeitos dos fármacos , Interleucinas/genética , Interleucinas/metabolismo , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas a Pancreatite , Proteínas/genética , Proteínas/metabolismo , Vancomicina/uso terapêutico , Interleucina 22
6.
Artigo em Inglês | MEDLINE | ID: mdl-27011794

RESUMO

BACKGROUND: Patients with cystic fibrosis (CF) complicated by allergic bronchopulmonary aspergillosis (ABPA) are vitamin D deficient and in vitro treatment with 1,25 (OH)2 vitamin D3 of CD4+ cells from CF patients with ABPA decreases Aspergillus fumigatus(Af)-induced Th2 responses. This Phase I clinical trial investigated the safety and effectiveness of daily vitamin D3 supplementation in CF patients with ABPA to reduce allergic responses and ABPA symptoms, and increase serum vitamin D levels. METHODS: Seven patients ages 12 years and older with a clinical diagnosis of CF and ABPA with current evidence of Af sensitization received 4000 IU vitamin D3 (cholecalciferol) daily for 24 weeks. The primary outcome of the study was safety followed by the Aspergillus induced IL-13 response in CD4+ T cells to test the hypothesis that vitamin D supplementation is safe and reduces Aspergillus induced IL-13 responses in CD4+ T cells. Secondary outcomes included total IgE, Aspergillus-specific IgE, vitamin D levels, FEV1, urinary calcium/creatinine ratio, and cytokine production by Aspergillus-stimulated peripheral blood T cells. RESULTS: Six months of vitamin D3 supplementation resulted in significant increases in serum 25-(OH) vitamin D level, and the treatment was well tolerated without evidence of vitamin D toxicity or hypercalcemia. There were no serious adverse events. Daily vitamin D supplementation led to significantly decreased Aspergillus induced IL-13 responses between the baseline visit and that at 24 weeks (p = 0.04). Aspergillus-specific IgE level was also significantly decreased after 8 (p = 0.035) and 24 weeks of daily vitamin D supplementation (p = 0.04). CONCLUSIONS: 4000 IU vitamin D3 daily over a 24-week period is well tolerated in CF patients with a history ABPA and current evidence of Th2 immunity to Af. . Daily vitamin D supplementation was associated with reduced Aspergillus induced IL-13 responses from peripheral. . CD4+ T cells and Aspergillus-specific IgE levels, as well as increased serum vitamin D levels. This treatment was well tolerated and the study supports further investigation of the use of vitamin D supplementation in Th2 mediated diseases. TRIAL REGISTRATION: This trial was registered at www.clinicaltrials.gov as NCT01222273.

7.
Infect Immun ; 81(5): 1510-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23439304

RESUMO

OX40 ligand (OX40L) is a costimulatory molecule involved in Th2 allergic responses. It has been shown that vitamin D deficiency is associated with increased OX40L expression in peripheral CD11c(+) cells and controls Th2 responses to Aspergillus fumigatus in vitro in cystic fibrosis (CF) patients with allergic bronchopulmonary aspergillosis (ABPA). To investigate if vitamin D deficiency regulated OX40L and Th2 responses in vivo, we examined the effect of nutritional vitamin D deficiency on costimulatory molecules in CD11c(+) cells and A. fumigatus-induced Th2 responses. Vitamin D-deficient mice showed increased expression of OX40L on lung CD11c(+) cells, and OX40L was critical for enhanced Th2 responses to A. fumigatus in vivo. In in vitro assays, vitamin D treatment led to vitamin D receptor (VDR) binding in the promoter region of OX40L and significantly decreased the promoter activity of the OX40L promoter. In addition, vitamin D altered NF-κB p50 binding in the OX40L promoter that may be responsible for repression of OX40L expression. These data show that vitamin D can act directly on OX40L, which impacts Th2 responses and supports the therapeutic use of vitamin D in diseases regulated by OX40L.


Assuntos
Aspergilose/imunologia , Aspergillus fumigatus/imunologia , Ligante OX40/metabolismo , Fatores de Necrose Tumoral/metabolismo , Deficiência de Vitamina D/imunologia , Vitamina D/farmacologia , Vitaminas/farmacologia , Análise de Variância , Animais , Aspergilose/metabolismo , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Feminino , Pulmão/citologia , Glicoproteínas de Membrana , Camundongos , Camundongos Endogâmicos BALB C , Subunidade p50 de NF-kappa B/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , Receptores de Calcitriol/metabolismo , Células Th2/imunologia , Deficiência de Vitamina D/metabolismo
8.
J Clin Invest ; 120(9): 3242-54, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20714107

RESUMO

Allergic bronchopulmonary aspergillosis (ABPA) is caused by a dominant Th2 immune response to antigens derived from the opportunistic mold Aspergillus, most commonly Aspergillus fumigatus. It occurs in 4%-15% of patients with cystic fibrosis (CF); however, not all patients with CF infected with A. fumigatus develop ABPA. Therefore, we compared cohorts of A. fumigatus-colonized CF patients with and without ABPA to identify factors mediating tolerance versus sensitization. We found that the costimulatory molecule OX40 ligand (OX40L) was critical in driving Th2 responses to A. fumigatus in peripheral CD4+ T cells isolated from patients with ABPA. In contrast, CD4+ T cells from the non-ABPA cohort did not mount enhanced Th2 responses in vitro and contained a higher frequency of TGF-beta-expressing regulatory T cells. Heightened Th2 reactivity in the ABPA cohort correlated with lower mean serum vitamin D levels. Further, in vitro addition of 1,25 OH-vitamin D3 substantially reduced DC expression of OX40L and increased DC expression of TGF-beta. This in vitro treatment also resulted in increased Treg TGF-beta expression and reduced Th2 responses by CD4+ T cells from patients with ABPA. These data provide rationale for a therapeutic trial of vitamin D to prevent or treat ABPA in patients with CF.


Assuntos
Aspergilose Broncopulmonar Alérgica/imunologia , Aspergillus fumigatus/imunologia , Linfócitos T CD4-Positivos/imunologia , Colecalciferol/farmacologia , Fibrose Cística/imunologia , Células Th2/imunologia , Adulto , Aspergillus/imunologia , Feminino , Humanos , Masculino , Receptores OX40/metabolismo , Linfócitos T Reguladores/imunologia , Fator de Crescimento Transformador beta/imunologia
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