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1.
Cancer Metastasis Rev ; 43(1): 409-421, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37950087

RESUMO

MYB transcription factors are encoded by a large family of highly conserved genes from plants to vertebrates. There are three members of the MYB gene family in human, namely, MYB, MYBL1, and MYBL2 that encode MYB/c-MYB, MYBL1/A-MYB, and MYBL2/B-MYB, respectively. MYB was the first member to be identified as a cellular homolog of the v-myb oncogene carried by the avian myeloblastosis virus (AMV) causing leukemia in chickens. Under the normal scenario, MYB is predominantly expressed in hematopoietic tissues, colonic crypts, and neural stem cells and plays a role in maintaining the undifferentiated state of the cells. Over the years, aberrant expression of MYB genes has been reported in several malignancies and recent years have witnessed tremendous progress in understanding of their roles in processes associated with cancer development. Here, we review various MYB alterations reported in cancer along with the roles of MYB family proteins in tumor cell plasticity, therapy resistance, and other hallmarks of cancer. We also discuss studies that provide mechanistic insights into the oncogenic functions of MYB transcription factors to identify potential therapeutic vulnerabilities.


Assuntos
Neoplasias , Fatores de Transcrição , Animais , Humanos , Plasticidade Celular/genética , Galinhas , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias/genética , Fatores de Transcrição/genética
2.
EMBO Rep ; 24(3): e55643, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36592158

RESUMO

Extensive desmoplasia and poor vasculature renders pancreatic tumors severely hypoxic, contributing to their aggressiveness and therapy resistance. Here, we identify the HuR/MYB/HIF1α axis as a critical regulator of the metabolic plasticity and hypoxic survival of pancreatic cancer cells. HuR undergoes nuclear-to-cytoplasmic translocation under hypoxia and stabilizes MYB transcripts, while MYB transcriptionally upregulates HIF1α. Upon MYB silencing, pancreatic cancer cells fail to survive and adapt metabolically under hypoxia, despite forced overexpression of HIF1α. MYB induces the transcription of several HIF1α-regulated glycolytic genes by directly binding to their promoters, thus enhancing the recruitment of HIF1α to hypoxia-responsive elements through its interaction with p300-dependent histone acetylation. MYB-depleted pancreatic cancer cells exhibit a dramatic reduction in tumorigenic ability, glucose-uptake and metabolism in orthotopic mouse model, even after HIF1α restoration. Together, our findings reveal an essential role of MYB in metabolic reprogramming that supports pancreatic cancer cell survival under hypoxia.


Assuntos
Neoplasias Pancreáticas , Camundongos , Animais , Neoplasias Pancreáticas/genética , Hipóxia , Regiões Promotoras Genéticas , Hipóxia Celular/genética , Linhagem Celular Tumoral , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética
3.
J Biol Chem ; 299(1): 102725, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36410437

RESUMO

MYB, a proto-oncogene, is overexpressed in prostate cancer (PCa) and promotes its growth, aggressiveness, and resistance to androgen-deprivation therapy. Here, we examined the effect of androgen signaling on MYB expression and delineated the underlying molecular mechanisms. Paralleling a dichotomous effect on growth, low-dose androgen induced MYB expression at both transcript and protein levels, whereas it was suppressed in high-dose androgen-treated PCa cells. Interestingly, treatment with both low- and high-dose androgen transcriptionally upregulated MYB by increasing the binding of androgen receptor to the MYB promoter. In a time-course assay, androgen induced MYB expression at early time points followed by a sharp decline in high-dose androgen-treated cells due to decreased stability of MYB mRNA. Additionally, profiling of MYB-targeted miRNAs demonstrated significant induction of miR-150 in high-dose androgen-treated PCa cells. We observed a differential binding of androgen receptor on miR-150 promoter with significantly greater occupancy recorded in high-dose androgen-treated cells than those treated with low-dose androgen. Functional inhibition of miR-150 relieved MYB suppression by high-dose androgen, while miR-150 mimic abolished MYB induction by low-dose androgen. Furthermore, MYB-silencing or miR-150 mimic transfection suppressed PCa cell growth induced by low-dose androgen, whereas miR-150 inhibition rescued PCa cells from growth repression by high-dose androgen. Similarly, we observed that MYB silencing suppressed the expression of androgen-responsive, cell cycle-related genes in low-dose androgen-treated cells, while miR-150 inhibition increased their expression in cells treated with high-dose androgen. Overall, these findings reveal novel androgen-mediated mechanisms of MYB regulation that support its biphasic growth control in PCa cells.


Assuntos
Androgênios , MicroRNAs , Neoplasias da Próstata , Proteínas Proto-Oncogênicas c-myb , Humanos , Masculino , Antagonistas de Androgênios , Androgênios/farmacologia , Androgênios/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Proteínas Proto-Oncogênicas c-myb/genética , Proteínas Proto-Oncogênicas c-myb/metabolismo , Processamento de Proteína Pós-Traducional , Células Tumorais Cultivadas
4.
Plant Physiol ; 193(2): 1197-1212, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37335936

RESUMO

Domestication is the long and complex process underlying the evolution of crops, in which artificial directional selection transformed wild progenitors into the desired form, affecting genomic variation and leaving traces of selection at targeted loci. However, whether genes controlling important domestication traits follow the same evolutionary pattern expected under the standard selective sweep model remains unclear. With whole-genome resequencing of mungbean (Vigna radiata), we investigated this issue by resolving its global demographic history and targeted dissection of the molecular footprints of genes underlying 2 key traits representing different stages of domestication. Mungbean originated in Asia, and the Southeast Asian wild population migrated to Australia about 50 thousand generations ago. Later in Asia, the cultivated form diverged from the wild progenitor. We identified the gene associated with the pod shattering resistance trait, VrMYB26a, with lower expression across cultivars and reduced polymorphism in the promoter region, reflecting a hard selective sweep. On the other hand, the stem determinacy trait was associated with VrDet1. We found that 2 ancient haplotypes of this gene have lower gene expression and exhibited intermediate frequencies in cultivars, consistent with selection favoring independent haplotypes in a soft selective sweep. In mungbean, contrasting signatures of selection were identified from the detailed dissection of 2 important domestication traits. The results suggest complex genetic architecture underlying the seemingly simple process of directional artificial selection and highlight the limitations of genome-scan methods relying on hard selective sweeps.


Assuntos
Fabaceae , Vigna , Vigna/genética , Locos de Características Quantitativas , Domesticação , Fabaceae/genética , Demografia , Seleção Genética
5.
Semin Cancer Biol ; 80: 237-255, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-32470379

RESUMO

The development of cancer is not just the growth and proliferation of a single transformed cell, but its surrounding environment also coevolves with it. Indeed, successful cancer progression depends on the ability of the tumor cells to develop a supportive tumor microenvironment consisting of various types of stromal cells. The interactions between the tumor and stromal cells are bidirectional and mediated through a variety of growth factors, cytokines, metabolites, and other biomolecules secreted by these cells. Tumor-stromal crosstalk creates optimal conditions for the tumor growth, metastasis, evasion of immune surveillance, and therapy resistance, and its targeting is being explored for clinical management of cancer. Natural agents from plants and marine life have been at the forefront of traditional medicine. Numerous epidemiological studies have reported the health benefits imparted on the consumption of certain fruits, vegetables, and their derived products. Indeed, a significant majority of anti-cancer drugs in clinical use are either naturally occurring compounds or their derivatives. In this review, we describe fundamental cellular and non-cellular components of the tumor microenvironment and discuss the significance of natural compounds in their targeting. Existing literature provides hope that novel prevention and therapeutic approaches will emerge from ongoing scientific efforts leading to the reduced tumor burden and improve clinical outcomes in cancer patients.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/prevenção & controle , Células Estromais/metabolismo , Microambiente Tumoral
6.
J Neuroophthalmol ; 43(3): 399-405, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255114

RESUMO

BACKGROUND: There is ongoing debate about whether the oculomotor (III), trochlear (IV), or abducens (VI) nerve paresis in patients with migraine is directly attributable to migraine (ophthalmoplegic migraine [OM]) or is due to an inflammatory neuropathy (recurrent painful ophthalmoplegic neuropathy [RPON]). As migraine is associated with elevated serum calcitonin gene-related peptide (CGRP) levels, we studied serum CGRP levels among patients with OM/RPON to determine whether they are elevated during and between attacks. This is the first study assessing CGRP levels in the serum of patients with OM/RPON. METHODS: The aim of this case-control study was to assess serum CGRP levels in patients with ophthalmoplegia and a headache consistent with migraine according to ICHD-3 criteria. Serum CGRP levels were measured during the ictal and interictal phases in 15 patients with OM/RPON and compared with age-matched and sex-matched controls without migraine (12 patients). RESULTS: The median serum CGRP levels were significantly elevated ( P = 0.021) during the ictal phase (37.2 [36.4, 43.6] ng/L) compared with controls (32.5 [30.1, 37.3] ng/L). Serum CGRP levels during the attack correlated with the total duration of ophthalmoplegia. A CGRP level of 35.5 ng/L in the ictal phase of the attack had a sensitivity of 86.7% and specificity of 75.0% in diagnosing a patient with OM/RPON. CONCLUSIONS: Elevated serum CGRP levels during the ictal phase of OM/RPON favor migraine as the underlying cause of episodic headache with ophthalmoplegia.


Assuntos
Transtornos de Enxaqueca , Oftalmoplegia , Enxaqueca Oftalmoplégica , Humanos , Peptídeo Relacionado com Gene de Calcitonina , Estudos de Casos e Controles , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/diagnóstico , Oftalmoplegia/diagnóstico , Enxaqueca Oftalmoplégica/diagnóstico , Cefaleia/diagnóstico
7.
Proc Natl Acad Sci U S A ; 117(25): 14543-14551, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32461376

RESUMO

The genetic architecture of quantitative traits is determined by both Mendelian and polygenic factors, yet classic examples of plant domestication focused on selective sweep of newly mutated Mendelian genes. Here we report the chromosome-level genome assembly and the genomic investigation of a nonclassic domestication example, bitter gourd (Momordica charantia), an important Asian vegetable and medicinal plant of the family Cucurbitaceae. Population resequencing revealed the divergence between wild and South Asian cultivars about 6,000 y ago, followed by the separation of the Southeast Asian cultivars about 800 y ago, with the latter exhibiting more extreme trait divergence from wild progenitors and stronger signs of selection on fruit traits. Unlike some crops where the largest phenotypic changes and traces of selection happened between wild and cultivar groups, in bitter gourd large differences exist between two regional cultivar groups, likely reflecting the distinct consumer preferences in different countries. Despite breeding efforts toward increasing female flower proportion, a gynoecy locus exhibits complex patterns of balanced polymorphism among haplogroups, with potential signs of selective sweep within haplogroups likely reflecting artificial selection and introgression from cultivars back to wild accessions. Our study highlights the importance to investigate such nonclassic example of domestication showing signs of balancing selection and polygenic trait architecture in addition to classic selective sweep in Mendelian factors.


Assuntos
Domesticação , Genoma de Planta , Momordica charantia/genética , Seleção Genética , Especiação Genética , Herança Multifatorial , Filogenia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
8.
Int J Mol Sci ; 24(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36901912

RESUMO

Prostate cancer (PCa) affects millions of men worldwide and is a major cause of cancer-related mortality. Race-associated PCa health disparities are also common and are of both social and clinical concern. Most PCa is diagnosed early due to PSA-based screening, but it fails to discern between indolent and aggressive PCa. Androgen or androgen receptor-targeted therapies are standard care of treatment for locally advanced and metastatic disease, but therapy resistance is common. Mitochondria, the powerhouse of cells, are unique subcellular organelles that have their own genome. A large majority of mitochondrial proteins are, however, nuclear-encoded and imported after cytoplasmic translation. Mitochondrial alterations are common in cancer, including PCa, leading to their altered functions. Aberrant mitochondrial function affects nuclear gene expression in retrograde signaling and promotes tumor-supportive stromal remodeling. In this article, we discuss mitochondrial alterations that have been reported in PCa and review the literature related to their roles in PCa pathobiology, therapy resistance, and racial disparities. We also discuss the translational potential of mitochondrial alterations as prognostic biomarkers and as effective targets for PCa therapy.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/patologia , Androgênios , Genoma , Núcleo Celular/patologia , Mitocôndrias/genética
9.
Br J Cancer ; 126(8): 1205-1214, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34837075

RESUMO

BACKGROUND: Aberrant activation of androgen receptor signalling following castration therapy is a common clinical observation in prostate cancer (PCa). Earlier, we demonstrated the role of MYB overexpression in androgen-depletion resistance and PCa aggressiveness. Here, we investigated MYB-androgen receptor (AR) crosstalk and its functional significance. METHODS: Interaction and co-localization of MYB and AR were examined by co-immunoprecipitation and immunofluorescence analyses, respectively. Protein levels were measured by immunoblot analysis and enzyme-linked immunosorbent assay. The role of MYB in ligand-independent AR transcriptional activity and combinatorial gene regulation was studied by promoter-reporter and chromatin immunoprecipitation assays. The functional significance of MYB in castration resistance was determined using an orthotopic mouse model. RESULTS: MYB and AR interact and co-localize in the PCa cells. MYB-overexpressing PCa cells retain AR in the nucleus even when cultured under androgen-deprived conditions. AR transcriptional activity is also sustained in MYB-overexpressing cells in the absence of androgens. MYB binds and promotes AR occupancy to the KLK3 promoter. MYB-overexpressing PCa cells exhibit greater tumorigenicity when implanted orthotopically and quickly regain growth following castration leading to shorter mice survival, compared to those carrying low-MYB-expressing prostate tumours. CONCLUSIONS: Our findings reveal a novel MYB-AR crosstalk in PCa and establish its role in castration resistance.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Proteínas Proto-Oncogênicas c-myb , Receptores Androgênicos , Androgênios/metabolismo , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Ligantes , Masculino , Camundongos , Orquiectomia , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Proteínas Proto-Oncogênicas c-myb/genética , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
10.
Am J Transplant ; 22(10): 2306-2322, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35671112

RESUMO

Human cytomegalovirus (HCMV) infection is associated with renal allograft failure. Allograft damage in animal models is accelerated by CMV-induced T helper 17 (Th17) cell infiltrates. However, the mechanisms whereby CMV promotes Th17 cell-mediated pathological organ inflammation are uncharacterized. Here we demonstrate that murine CMV (MCMV)-induced intragraft Th17 cells have a Th1/17 phenotype co-expressing IFN-γ and/or TNF-α, but only a minority of these cells are MCMV specific. Instead, MCMV promotes intragraft expression of CCL20 and CXCL10, which are associated with recruitment of CCR6+ CXCR3+ Th17 cells. MCMV also enhances Th17 cell infiltrates after ischemia-reperfusion injury, independent of allogeneic responses. Pharmacologic inhibition of the Th17 cell signature cytokine, IL-17A, ameliorates MCMV-associated allograft damage without increasing intragraft viral loads or reducing MCMV-specific Th1 cell infiltrates. Clinically, HCMV DNAemia is associated with higher serum IL-17A among renal transplant patients with acute rejection, linking HCMV reactivation with Th17 cell cytokine expression. In summary, CMV promotes allograft damage via cytokine-mediated Th1/17 cell recruitment, which may be pharmacologically targeted to mitigate graft injury while preserving antiviral T cell immunity.


Assuntos
Infecções por Citomegalovirus , Transplante de Rim , Muromegalovirus , Nefrite , Insuficiência Renal , Aloenxertos/metabolismo , Animais , Antivirais , Citocinas/metabolismo , Humanos , Inflamação/patologia , Interleucina-17/metabolismo , Transplante de Rim/efeitos adversos , Camundongos , Insuficiência Renal/complicações , Células Th1 , Células Th17 , Fator de Necrose Tumoral alfa/metabolismo
11.
BMC Cancer ; 22(1): 1074, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36258167

RESUMO

BACKGROUNDS: Microbiome dysbiosis is an important contributing factor in tumor development and thus may be a risk predictor for human malignancies. In the United States, women with Hispanic/Latina (HIS) and African American (AA) background have a higher incidence of cervical cancer and poorer outcomes than Caucasian American (CA) women. METHODS: Here, we assessed the distribution pattern of microbiota in cervical intraepithelial neoplasia (CIN) lesions obtained from HIS (n = 12), AA (n = 12), and CA (n = 12) women, who were screened for CC risk assessment. We employed a 16S rRNA gene sequencing approach adapted from the NIH-Human Microbiome Project to identify the microbial niche in all CIN lesions (n = 36). RESULTS: We detected an appreciably decreased abundance of beneficial Lactobacillus in the CIN lesions of the AA and HIS women compared to the CA women. Differential abundance of potentially pathogenic Prevotella, Delftia, Gardnerella, and Fastidiosipila was also evident among the various racial groups. An increased abundance of Micrococcus was also evident in AA and HIS women compared to the CA women. The detection level of Rhizobium was higher among the AA ad CA women compared to the HIS women. In addition to the top 10 microbes, a unique niche of 27 microbes was identified exclusively in women with a histopathological diagnosis of CIN. Among these microbes, a group of 8 microbiota; Rubellimicrobium, Podobacter, Brevibacterium, Paracoccus, Atopobium, Brevundimonous, Comamonous, and Novospingobium was detected only in the CIN lesions obtained from AA and CA women. CONCLUSIONS: Microbial dysbiosis in the cervical epithelium represented by an increased ratio of potentially pathogenic to beneficial microbes may be associated with increased CC risk disparities. Developing a race-specific reliable panel of microbial markers could be beneficial for CC risk assessment, disease prevention, and/or therapeutic guidance.


Assuntos
Microbiota , Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Papillomaviridae/genética , RNA Ribossômico 16S/genética , Infecções por Papillomavirus/complicações , Disbiose , Neoplasias do Colo do Útero/patologia , Microbiota/genética , Displasia do Colo do Útero/epidemiologia
12.
Lupus ; 31(9): 1054-1066, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35607991

RESUMO

OBJECTIVE: Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease, which is known to be associated with HLA-DRB1 and Epstein-Barr virus (EBV) infection. In the Indian subcontinent where there is high seroendemicity of EBV, we postulated that the association of this virus in adult SLE (aSLE) and pediatric SLE (pSLE) patients would be different and differentially associate with the HLA-DRB1 susceptibility and protective genes. METHODS: A total of 109 aSLE, 52 pSLE, 215 adult healthy and 63 pediatric healthy controls were recruited. HLA-DRB1 genotyping by PCR-SSP, EBV load estimation by real-time PCR and antibody profiling (IgG & IgM) to EBV antigens by line blot assay were performed. RESULTS: DRB1*15 was found predominant in pSLE patients and DRB1*03 in aSLE patients. DRB1*15/X heterozygous was predominant in overall SLE patients, although disease severity, like hypocomplementemia, higher autoantibody levels and more organ involvement was observed in *15/*15 homozygous state. EBV strongly associated with pSLE patients showing higher percent of EA-D IgG (p < 0.0001) and p22 IgG (p = 0.035) along with higher viral load (p = 0.001) as compared to healthy controls. In addition, the higher EBV DNA load significantly associated with anti-EA-D IgG (p = 0.013) and DRB1*15/*15 (p = 0.007) in pSLE patients as compared to aSLE patients. CONCLUSIONS: This study therefore indicates that different HLA-DRB1 allotypes confer susceptibility to SLE in children and adults and disease may be triggered by increased EBV reactivation.


Assuntos
Infecções por Vírus Epstein-Barr , Lúpus Eritematoso Sistêmico , Adulto , Criança , Cadeias HLA-DRB1/genética , Herpesvirus Humano 4/genética , Humanos , Imunidade , Imunoglobulina G , Lúpus Eritematoso Sistêmico/complicações , Carga Viral
13.
Pathol Int ; 72(5): 283-292, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35319814

RESUMO

Antinuclear antibody (ANA) pattern and autoantibody (autoAb) profiling of 150 adult systemic sclerosis (SSc) patients concerning their clinical association and diagnostic significance were analyzed by indirect immunofluorescence (IIF), immunoblot, and fluorescence enzyme immunoassay. One hundred and forty-three (95.3%) patients had positive ANA: DNA topoisomerase I (topo I)-like pattern-84(56%); speckled pattern-44(29.3%);centromere pattern-7(4.6%); and nucleolar pattern-4(2.6%). Three distinct topo I-like immunofluorescence patterns were detected at 1:40 dilution. Topo I-like pattern (32/75-limited cutaneous systemic sclerosis (lcSSc) vs. 52/75-diffuse cutaneous systemic sclerosis (dcSSc); p < 0.001) was found to be associated with dcSSc subset and speckled pattern (lcSSc 28/75 vs. dcSSc 16/75; p < 0.03) with lcSSc subset. One hundred and thirty-eight (92%) patients were positive for SSc-associated autoAbs. The frequency distribution of autoAbs to topo I, centromere A (CENP A) and centromereB (CENP B), RNA polymerase III (RP11, RP155), fibrillarin (U3RNP), nucleolus organizer region (NOR)-90, Th/To, PM-Scl75, PM-Scl100, Ku, platelet-derived growth factor receptor (PDGFR) and Ro-52, were 87(58%), 9(6%), 8(5.3%), 6(4%), 9(6%), 0, 6(4%), 6(4%), 8(5.3%), 5(3.3%), 11(7.3%),0 and 46(30.6%), respectively. Topo I autoAb was strongly associated with dcSSc (35/75 lcSSc vs. 52/75 dcSSc; p < 0.004), Raynaud's (p < 0.003), interstitial lung disease (ILD) (p < 0.001) and pulmonary arterial hypertension (PAH) (p < 0.04). This study helps in defining SSc clinical subset, prognostic markers of disease severity, characterization of the topo I-like ANA pattern, and provides a definite association between the ANA patterns and corresponding autoAb.


Assuntos
Anticorpos Antinucleares , Escleroderma Sistêmico , Adulto , Autoanticorpos , Humanos , RNA Polimerase III , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/diagnóstico , Centros de Atenção Terciária
14.
Med Teach ; 43(2): 137-141, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33142072

RESUMO

As the early epicenter of the COVID-19 pandemic, New York City's medical schools experienced dramatic disruptions in every aspect of medical education. Remote learning was created, seemingly overnight, clerkships were disrupted, licensing examinations were cancelled, teaching faculty were redeployed, student volunteers rallied, and everyone was required to shelter at home. Seismic changes were required to adapt the authors' educational programs to a constantly evolving, unpredictable, and ever-worsening public health crisis. Entirely new communication strategies were adopted and thousands of decisions had to be made, often with little time to carefully reflect on the consequences of those decisions. What allowed each school to navigate these treacherous waters was a set of guiding principles that were used to ground each conversation, and inform every decision. While the language varied somewhat between schools, the core principles were universal and framed a way forward at a time when information, data, precedent, and best practices did not exist. The authors share these guiding principles in the hope that colleagues at other medical schools will find them to be a useful framework as we all continue to cope with the impact of COVID-19 on the future of medical education.


Assuntos
COVID-19/epidemiologia , Educação de Graduação em Medicina/tendências , Faculdades de Medicina/tendências , Telemedicina/tendências , Competência Clínica/estatística & dados numéricos , Currículo/tendências , Humanos , Pandemias/estatística & dados numéricos , Distanciamento Físico , Guias de Prática Clínica como Assunto , Estudantes de Medicina/estatística & dados numéricos
15.
Inflammopharmacology ; 29(1): 137-151, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33386490

RESUMO

The initial precipitating injury such as SE progresses to chronic epilepsy through multiple epileptogenic processes. Early epileptogenic events are generally characterized by neuroinflammation, neurodegeneration and abnormal neurogenesis in the hippocampus. Metformin has exhibited anti-inflammatory and neuroprotective properties in numerous studies. The current study attempts to investigate the effect of metformin on seizure-induced inflammation and neuronal degeneration, and the involvement of the mTOR pathway. Status epilepticus (SE) was induced in male Wistar rats with systemic administration of Lithium (127 mg/kg) and Pilocarpine (30 mg/kg). In test rats, Metformin 100 mg/kg or 200 mg/kg was administered orally for 7 days, followed by SE induction. Results indicate that metformin did not alter the SE profile significantly which was evident by the behavioural scoring and electroencephalogram (EEG) recordings. However, metformin 200 mg/kg attenuated the SE-induced glial activation (p < 0.01), up regulated mRNA levels of proinflammatory cytokines (p < 0.001) and chemokines (p < 0.001) and enhanced BBB permeability (p < 0.05). In addition, metformin ameliorated the insult-induced region-specific neuronal damage (p < 0.01) and restored the hippocampal neuronal density. Metformin significantly inhibited phosphorylated S6 ribosomal protein (phospho-S6rp) (p < 0.05), thus demonstrating that the beneficial effects might be partly mediated by the mTOR pathway. The study thus reiterates that mTOR signalling is one of the mechanisms involved in inflammation and neurodegeneration in early epileptogenesis following SE.


Assuntos
Hipocampo/efeitos dos fármacos , Metformina/farmacologia , Fármacos Neuroprotetores/farmacologia , Estado Epiléptico/tratamento farmacológico , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hipocampo/patologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Metformina/administração & dosagem , Neurônios/patologia , Fármacos Neuroprotetores/administração & dosagem , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Estado Epiléptico/fisiopatologia , Serina-Treonina Quinases TOR/metabolismo
16.
Int J Mol Sci ; 21(15)2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32759795

RESUMO

RAB proteins (RABs) represent the largest subfamily of Ras-like small GTPases that regulate a wide variety of endosomal membrane transport pathways. Their aberrant expression has been demonstrated in various malignancies and implicated in pathogenesis. Using The Cancer Genome Atlas (TCGA) database, we analyzed the differential expression and clinicopathological association of RAB genes in pancreatic ductal adenocarcinoma (PDAC). Of the 62 RAB genes analyzed, five (RAB3A, RAB26, RAB25, RAB21, and RAB22A) exhibited statistically significant upregulation, while five (RAB6B, RAB8B, RABL2A, RABL2B, and RAB32) were downregulated in PDAC as compared to the normal pancreas. Racially disparate expression was also reported for RAB3A, RAB25, and RAB26. However, no clear trend of altered expression was observed with increasing stage and grade, age, and gender of the patients. PDAC from occasional drinkers had significantly higher expression of RAB21 compared to daily or weekly drinkers, whereas RAB25 expression was significantly higher in social drinkers, compared to occasional ones. The expression of RABL2A was significantly reduced in PDAC from diabetic patients, whereas RAB26 was significantly lower in pancreatitis patients. More importantly, a significant association of high expression of RAB21, RAB22A, and RAB25, and low expression of RAB6B, RABL2A, and RABL2B was observed with poorer survival of PC patients. Together, our study suggests potential diagnostic and prognostic significance of RABs in PDAC, warranting further investigations to define their functional and mechanistic significance.


Assuntos
Adenocarcinoma/genética , Biomarcadores Tumorais/genética , Neoplasias Pancreáticas/genética , Prognóstico , Adenocarcinoma/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Mitocondriais/genética , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/patologia , Intervalo Livre de Progressão , Proteínas rab de Ligação ao GTP/genética , Proteína rab3A de Ligação ao GTP/genética , Proteínas ras/genética
17.
Indian J Med Res ; 149(1): 18-25, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31115370

RESUMO

BACKGROUND & OBJECTIVES: : Celiac disease (CD) can exist in various forms in type 1 diabetes (T1D) patients and can remain undetected, leading to severe complications. This study was aimed to evaluate five commercially available anti-tissue transglutaminase (tTG) ELISA kits with distinct formats for the detection of CD and potential CD in T1D patients. Clinical and demographic profiles of the patients with different disease subsets were also studied. METHODS: : Fifty T1D patients with classical and non-classical symptoms of CD and 100 T1D patients without any symptoms of CD were included in this study. Anti-tTG autoantibody levels were estimated by five ELISA kits followed by histological examination of duodenal biopsy. HLA DQ2-DQ8 and DRB1-DQB1 typing was done, and serum levels for transforming growth factor (TGF)-ß1 were also estimated. RESULTS: : Assay format detecting anti-tTG IgA antibodies against recombinant antigens along with neopeptides of gliadin was most efficient in the detection of CD in symptomatic patients, and assay format detecting IgA+IgG helped in the detection of potential CD in asymptomatic T1D patients. These findings were supported by histological examination and human leucocyte antigen analysis. Patients with potential CD were found to have markedly deranged glycaemic control parameters and also had significantly raised serum levels of TGF-ß1, (P <0.05) compared to T1D patients. INTERPRETATION & CONCLUSIONS: : Potential CD can be frequently seen in T1D patients. This can be attributed to the dietary patterns prevalent in the subcontinent and the genetic basis of the disease. Anti-tTG IgA+IgG antibodies can be useful in the detection of these potential CD cases in T1D patients. Early intervention with gluten-free diet can be considered in these patients for better disease management.


Assuntos
Doença Celíaca/sangue , Diabetes Mellitus Tipo 1/sangue , Transglutaminases/isolamento & purificação , Adolescente , Adulto , Anticorpos Anti-Idiotípicos/imunologia , Autoanticorpos/imunologia , Doença Celíaca/complicações , Doença Celíaca/dietoterapia , Doença Celíaca/imunologia , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/dietoterapia , Diabetes Mellitus Tipo 1/imunologia , Dieta Livre de Glúten , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Pessoa de Meia-Idade , Fator de Crescimento Transformador beta1/sangue , Transglutaminases/imunologia , Adulto Jovem
18.
Clin Exp Nephrol ; 22(2): 465-473, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28849286

RESUMO

BACKGROUND: Ability to predict the manner in which a recipient's immune system would respond to a transplanted graft by analyzing cytokine profiles of the "allograft antigen sensitized" recipient lymphocytes in vitro might provide a means to identify patients at risk to adverse clinical endpoints. METHODS: Cytokine/chemokine gene expression profiles of peripheral blood mononuclear cells co-cultured with allograft antigen-pulsed macrophages were studied in 49 renal transplant recipients-12 with acute cellular rejection (ACR) with or without antibody-mediated rejection (AMR), 7 with AMR (without ACR), and 30 with stable allografts (SA). An 86-gene inflammatory cytokines and receptors PCR array was used to measure fold changes in gene expression between pulsed and un-pulsed cultures. RESULTS: On linear discriminant analysis and multivariate analysis of variance, a gene set comprising C3, CCL3, IL1B, TOLLIP, IL10, CXCL5, ABCF1, CCR3, IL10RB, CXCL1, and IL1R1 differentiated the ACR-AMR from the SA group. Similarly, a gene set comprising IL10, C3, IL37, IL1B, CCL3, CARD18, and TOLLIP differentiated the AMR from the SA group. No significant difference was found between the ACR-AMR vs AMR groups. CONCLUSION: Distinct post in vitro stimulation cytokine profiles at the time of transplantation thus correlated with the occurrence of post-transplantation rejection episodes which indicated feasibility of this in vitro model to assess the recipient's anti-graft response at an early stage.


Assuntos
Citocinas/genética , Citocinas/imunologia , Perfilação da Expressão Gênica/métodos , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Teste de Histocompatibilidade/métodos , Isoantígenos/imunologia , Transplante de Rim/efeitos adversos , Linfócitos/imunologia , Adulto , Aloenxertos , Estudos de Casos e Controles , Células Cultivadas , Técnicas de Cocultura , Análise Discriminante , Feminino , Rejeição de Enxerto/sangue , Rejeição de Enxerto/diagnóstico , Humanos , Imunidade Celular , Imunidade Humoral , Modelos Lineares , Macrófagos/imunologia , Masculino , Análise Multivariada , Análise de Sequência com Séries de Oligonucleotídeos , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Transcriptoma , Resultado do Tratamento
20.
J Cutan Pathol ; 44(4): 346-351, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28058749

RESUMO

INTRODUCTION: Psoriasis is a multisystem, immune-mediated inflammatory disease. Some authors have proposed an autoimmune basis for psoriasis; however, till date, it has not been definitely established. This study was conducted to explore the autoimmune nature of psoriasis. MATERIALS AND METHODS: This was a prospective study in which 43 psoriasis patients were assessed for detailed clinical, histopathological and immunopathological features to explore the diagnostic utility of subtypes, intensity and number of immunoreactants in lesional and non-lesional skin in these patients. In addition, the sera of these patients were analyzed for the presence of various autoantibodies. RESULTS: The patients' age ranged from 14 to 75 years with a male-to-female ratio of 1.52:1. Nine patients (20.93%) were positive for antinuclear and 2 (4.65%) for antismooth muscle antibodies. Direct immunofluorescence (DIF) was positive in 31 (72%) biopsies from the lesional and 27 (63%) biopsies from non-lesional skin. In all these DIF positive cases, granular deposits of C5b-9 were detected at the dermoepidermal junction. No significant difference was observed on comparing the type and pattern of immunoreactant positivity, among lesional and non-lesional skin biopsies (P > .05). CONCLUSION: No significant association between psoriasis and immunoreactant deposition as well as autoantibody seroprevalence was observed, thereby refuting a definite autoimmune basis for psoriasis.


Assuntos
Autoanticorpos/metabolismo , Doenças Autoimunes , Psoríase , Pele , Adolescente , Adulto , Idoso , Doenças Autoimunes/metabolismo , Doenças Autoimunes/patologia , Feminino , Humanos , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Psoríase/metabolismo , Psoríase/patologia , Pele/metabolismo , Pele/patologia
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