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1.
Int J Surg Case Rep ; 120: 109837, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38833904

RESUMO

INTRODUCTION AND IMPORTANCE: Polyorchidism, or supernumerary testis, is a rare urogenital congenital disorder. Because of its rarity, there is no approved standard treatment protocol for preserving or removing the extra testicle, yet orchiopexy is frequently performed as a preferred treatment in most medical facilities. CASE PRESENTATION: We present a 23-year-old single male with a bilaterally empty scrotum. He was unaware of his condition and had not seen a doctor before being admitted to our surgical unit. During his younger sibling's circumcision by a local circumcisionist (a medical staff member, idealy a nurse, whose duty is to perform circumcision, preferably at home), he saw something different (his emptey scrotum) and came to us with his problem. Laboratory findings revealed severe oligospermia, and tumor markers (Alpha fetoprotein, beta-human chorionic gonadotropin, and lactate dehydrogenase) were negative for malignancy. The patient underwent bilateral herniorrhaphy and orchiopexy of all six testicles (three in each inguinal canal) and had an uneventful recovery. CLINICAL DISCUSSION: As polyorchidism is not a common problem, its management remains a contentious issue due to the lack of evidence-based consensus. However, with the introduction of new imaging modalities and on-table frozen section biopsy, the decision to continue with orchiopexy or orchiectomy can be easily justified; however, conservative treatment is preferable in cases of no coexisting anomalies, particularly cryptorchidism. CONCLUSION: Polyorchidism could run unnoticed for years, especially if there is no direct and consistent access to a medical facility. In cases where polyorchidism is detected accidentally by imaging or during surgical exploration, the treatment must be justified accordingly.

3.
Vector Borne Zoonotic Dis ; 23(12): 634-638, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37603293

RESUMO

Background: In Bangladesh, dengue has been prevalent since its resurgence in 2018, and the dominant causative virus in 2019 was considered dengue virus serotype 3 (DENV-3). However, limited information is available for DENV serotype/genotype circulating after 2020. Materials and Methods: Viral RNA was extracted from NS1 antigen-positive blood samples of febrile patients in Dhaka, in 2021. DENV gene was detected by semi-nested RT-PCR, and sequences of envelope (E) gene and C-prM gene were determined by direct sequencing of RT-PCR products for genetic analysis. Results: Among 172 NS1-positive samples collected, 91 samples were assigned to DENV-3 and DENV-2 (88 and 3 samples, respectively) by RT-PCR targeting the C-prM gene. Phylogenetic analysis of the E gene for the 17 representative DENV-3 samples showed that all the viruses belonged to genotype I, forming a cluster (B-cluster) with those of DENV-3 reported in Bangladesh in 2017. Analysis of the deduced amino acid sequences of E protein revealed 16 amino acid substitutions, including two novel ones (G221W, L285P), and a substitution T223I that was specifically found in DENV-3 B-cluster. Conclusion: This study showed the persistent predominance of DENV-3 genotype I in Bangladesh having unique genetic traits in the E gene. (Approval number: MMC/IRB/2022/468).


Assuntos
Vírus da Dengue , Dengue , Humanos , Vírus da Dengue/genética , Dengue/epidemiologia , Dengue/veterinária , Filogenia , Bangladesh/epidemiologia , Sorogrupo , Genótipo
4.
Oncogene ; 41(50): 5361-5372, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36344676

RESUMO

Glioma stem cells (GSCs) promote tumor progression and therapeutic resistance and exhibit remarkable bioenergetic and metabolic plasticity, a phenomenon that has been linked to their ability to escape standard and targeted therapies. However, specific mechanisms that promote therapeutic resistance have been somewhat elusive. We hypothesized that because GSCs proliferate continuously, they may require the salvage and de novo nucleotide synthesis pathways to satisfy their bioenergetic needs. Here, we demonstrate that GSCs lacking EGFR (or EGFRvIII) amplification are exquisitely sensitive to de novo pyrimidine synthesis perturbations, while GSCs that amplify EGFR are utterly resistant. Furthermore, we show that EGFRvIII promotes BAY2402234 resistance in otherwise BAY2402234 responsive GSCs. Remarkably, a novel, orally bioavailable, blood-brain-barrier penetrating, dihydroorotate dehydrogenase (DHODH) inhibitor BAY2402234 was found to abrogate GSC proliferation, block cell-cycle progression, and induce DNA damage and apoptosis. When dosed daily by oral gavage, BAY2402234 significantly impaired the growth of two different intracranial human glioblastoma xenograft models in mice. Given this observed efficacy and the previously established safety profiles in preclinical animal models and human clinical trials, the clinical testing of BAY2402234 in patients with primary glioblastoma that lacks EGFR amplification is warranted.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Camundongos , Animais , Di-Hidro-Orotato Desidrogenase , Células-Tronco Neoplásicas/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Glioma/tratamento farmacológico , Glioma/genética , Glioma/patologia , Dano ao DNA , Proliferação de Células , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral
5.
Sci Rep ; 12(1): 15400, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100633

RESUMO

Severe lodging has recurrently occurred at strong typhoon's hitting in recent climate change. The identification of quantitative trait loci and their responsible genes associated with a strong culm and their pyramiding are important for developing high-yielding varieties with a superior lodging resistance. To evaluate the effects of four strong-culm genes on lodging resistance, the temperate japonica near isogenic line (NIL) with the introgressed SCM1 or SCM2 locus of the indica variety, Habataki and the other NIL with the introgeressed SCM3 or SCM4 locus of the tropical japonica variety, Chugoku 117 were developed. Then, we developed the pyramiding lines with double,triple and quadruple combinations derived from step-by-step crosses among NIL-SCM1-NIL-SCM4. Quadruple pyramiding line (NIL-SCM1 + 2 + 3 + 4) showed the largest culm diameter and the highest culm strength among the combinations and increased spikelet number due to the pleiotropic effects of these genes. Pyramiding of strong culm genes resulted in much increased culm thickness, culm strength and spikelet number due to their additive effect. SCM1 mainly contributed to enhance their pyramiding effect. These results in this study suggest the importance of identifying the combinations of superior alleles of strong culm genes among natural variation and pyramiding these genes for improving high-yielding varieties with a superior lodging resistance.


Assuntos
Oryza , Alelos , Feminino , Humanos , Oryza/genética , Gravidez , Gravidez Múltipla , Locos de Características Quantitativas
6.
Front Public Health ; 10: 905481, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910864

RESUMO

Background: The United States Armed Forces completed their withdrawal from Afghanistan on August 30th, 2021, ending 20 years of war in Afghanistan. This rapid timeline from announcement to withdrawal and subsequent power transfer had profound consequences on the Afghan people, particularly in the domains of health and healthcare. Methods: On 15 September 2021, we posted an anonymous online cross-sectional survey on social media (Twitter, Facebook, and WhatsApp groups) to collect data about respondents from Afghanistan. Questions focused on COVID-19 symptoms, concerns, and individual care with a focus on changes related to the United States (US) withdrawal from Afghanistan. The form was composed of 17 questions which included multiple choice, single choice, and numeric options. All questions were optional including demographic data. Results: Our survey yielded 1,074 responses from the Farsi version and 572 responses from the Pashto version for a total of 1,646 responses. 1,286 (80%) of respondents were in Afghanistan at the time of survey submission. Concerning the US withdrawal from Afghanistan, 26% (412) respondents were extremely concerned and 12% (181) were moderately concerned. A majority of respondents report concerns regarding mental health due to the US withdrawal. 27% (418) report extreme concern, 12% (186) report moderate concern, and 15% (229) report a little concern. There is a significant difference in the proportions of concern (for US withdrawal generally, as well as physical and mental health) across gender. 49% of Female respondents report extreme concern regarding the US withdrawal compared to 22% of Male respondents (P < 0.001). With respect to physical health concerns 36% of Females report extreme concern compared to 16% of Males (P < 0.001). Finally on the mental health concerns, 54% of Females report extreme concern compared to 22% of Males (P < 0.001). Conclusion: The results from this survey are susceptible to the possibility of internal validity and/or external validity. However, we are accepting of those possibilities considering this survey wasn't designed to be bulletproof, but rather serve as a voice for those who can't be heard and to inform the public of the hardships occurring across the globe due to a steadfast retraction of the US footprint from their soil. Our findings indicate salient changes and public health concerns among Afghans following the US withdrawal from the region. These concerns varied across gender and ethnic groups. Our findings may serve as the first step in addressing the health concerns of Afghans following two decades of US military presence. The results should be understood through the limitations associated with a survey study design. Future research and policy aimed at tackling short and long-term health and social concerns in Afghanistan should consider the role of US withdrawal.


Assuntos
COVID-19 , Mídias Sociais , COVID-19/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Saúde Mental , Inquéritos e Questionários , Estados Unidos/epidemiologia
7.
Br J Cancer ; 125(9): 1185-1196, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34262149

RESUMO

Although low risk localised prostate cancer has an excellent prognosis owing to effective treatments, such as surgery, radiation, cryosurgery and hormone therapy, metastatic prostate cancer remains incurable. Existing therapeutic regimens prolong life; however, they are beset by problems of resistance, resulting in poor outcomes. Treatment resistance arises primarily from tumour heterogeneity, altered genetic signatures and metabolic reprogramming, all of which enable the tumour to serially adapt to drugs during the course of treatment. In this review, we focus on alterations in the metabolism of prostate cancer, including genetic signatures and molecular pathways associated with metabolic reprogramming. Advances in our understanding of prostate cancer metabolism might help to explain many of the adaptive responses that are induced by therapy, which might, in turn, lead to the attainment of more durable therapeutic responses.


Assuntos
Redes e Vias Metabólicas , Neoplasias da Próstata/metabolismo , Reprogramação Celular , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Masculino , Fosforilação Oxidativa , Prognóstico , Neoplasias da Próstata/genética
8.
J Med Chem ; 64(8): 4762-4786, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33835811

RESUMO

A benzo[6]annulene, 4-(tert-butyl)-N-(3-methoxy-5,6,7,8-tetrahydronaphthalen-2-yl) benzamide (1a), was identified as an inhibitor against Chikungunya virus (CHIKV) with antiviral activity EC90 = 1.45 µM and viral titer reduction (VTR) of 2.5 log at 10 µM with no observed cytotoxicity (CC50 = 169 µM) in normal human dermal fibroblast cells. Chemistry efforts to improve potency, efficacy, and drug-like properties of 1a resulted in a novel lead compound 8q, which possessed excellent cellular antiviral activity (EC90 = 270 nM and VTR of 4.5 log at 10 µM) and improved liver microsomal stability. CHIKV resistance to an analog of 1a, compound 1c, tracked to a mutation in the nsP3 macrodomain. Further mechanism of action studies showed compounds working through inhibition of human dihydroorotate dehydrogenase in addition to CHIKV nsP3 macrodomain. Moderate efficacy was observed in an in vivo CHIKV challenge mouse model for compound 8q as viral replication was rescued from the pyrimidine salvage pathway.


Assuntos
Antivirais/farmacologia , Derivados de Benzeno/química , Vírus Chikungunya/fisiologia , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/química , Antivirais/farmacocinética , Antivirais/uso terapêutico , Derivados de Benzeno/metabolismo , Derivados de Benzeno/farmacologia , Derivados de Benzeno/uso terapêutico , Sítios de Ligação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Febre de Chikungunya/tratamento farmacológico , Di-Hidro-Orotato Desidrogenase , Modelos Animais de Doenças , Feminino , Meia-Vida , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microssomos Hepáticos/metabolismo , Simulação de Acoplamento Molecular , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Relação Estrutura-Atividade
9.
Trop Med Infect Dis ; 6(2)2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33919249

RESUMO

Bangladesh is an endemic region of dengue fever and experienced an unprecedented large outbreak with more than 100,000 confirmed cases in 2019. To understand the prevalence of dengue antibody in patients and molecular epidemiological characteristics of dengue virus (DENV) in this outbreak, a total of 179 blood samples were collected from patients in 10 districts (seven divisions) covering nearly the whole country from August to December 2019. DENV NS-1 was detected in 162 samples, among which DENV-specific IgM was positive in 119 samples (73.5%), including 60.5% samples also positive for DENV-specific IgG. Sequencing of the partial C-prM gene and its phylogenetic analysis revealed predominance of DENV type 3 genotype I, accounting for 93% of samples examined. DENV-3 genotype III was identified in two samples from separate districts, and only one DENV-2 cosmopolitan genotype was found in the capital city, Dhaka. These findings suggest the predominance of DENV-3 genotype I and occurrence of DENV-3 genotype III, associated with increased incidence of recent secondary infection in Bangladesh in 2019.

10.
Curr Pharm Des ; 27(33): 3566-3576, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33327904

RESUMO

BACKGROUND: Recent emergence of COVID-19 caused by a new human coronavirus (CoV) strain (SARS-CoV-2), which originated from China, poses the future emergence of additional CoVs. In most of the cases of emergence of human CoVs, bats, palm civets, raccoon dogs and camels have been identified as the sources of human infections and as reservoir hosts. A review of comparative genomic and phenotypic characteristics of human CoV strains vis-à-vis their comparison with the corresponding animal isolates shall provide clues regarding the potential genomic, phenotypic and molecular factors responsible for host-switching, which may lead to prospective emergence and re-emergence of human CoV outbreaks in the future. METHODS: The seven known human strains of CoV were analyzed for the host and viral factors responsible for human outbreaks. The molecular factors responsible for host-susceptibility, virulence and pathogenesis were reviewed to predict the emergence and re-emergence of additional human CoV strains. CoV spike protein was evaluated as a potential viral receptor for host switching and the target for pharmaceutical design. RESULTS: A review of the factors associated with host-susceptibility, virulence and pathogenesis of seven known human CoV strains presents significant possibilities for the emergence of new CoV strain(s), leading to more human outbreaks. Continuous exposure of animals' handlers to the infected animals, environmental changes, improper sanitations, non-disposal of the solid waste and resumption of exotic animals markets provides favorable conditions for "host switching" and the emergence of new and potentially more virulent human CoV strains. Mutations in target genes (like spike protein), which facilitate the viral entry into the host-cells, provide a potential "molecular switch" for preferences of new host-receptors, genetic diversity, genetic-recombination and high virulence. Additionally, the clinical and environmental factors, asymptomatic carriers, the paucity of efficacious vaccines & therapeutics, inefficient disease management and infection control measures, lack of public awareness, and effective communication of information about more virulent human-adapted virus isolates are critical for the emergence of new and virulent SARS-CoV strains with high mortality and varied incubation period in the near future. Small molecules binding with conserved druggable regions of the CoV spike proteins may be effective against multiple strains of CoVs. CONCLUSION: High propensity of mutations and "molecular adaptations" in coronaviruses creates the hot spots and high potential for "host switching", leading to the emergence of more virulent strains of human CoVs. The public/global health agencies, medical communities and research scientists should be prepared for the emergence and re-emergence of new human CoV strain(s) leading to potential disease outbreaks. The inhibitors binding with conserved druggable regions of spike proteins from multiple strains CoV may have utility as broad-spectrum antiviral drugs to combat future emergence of CoVs.


Assuntos
COVID-19 , Preparações Farmacêuticas , Animais , Humanos , Estudos Prospectivos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
11.
Curr Pharm Des ; 26(41): 5286-5292, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32954998

RESUMO

BACKGROUND: Human coronaviruses (HCoV) are common viruses and known to be associated with respiratory diseases, including pneumonia. Currently, seven human coronaviruses have been identified and known to cause upper and lower respiratory infections as well as nosocomial viral infections in humans. The bats, palm civets, and camels are identified as the reservoir of human coronaviruses. In 2002-2003, the emergence of SARS-CoV resulted in an outbreak and led towards the more awareness and importance of scientific research and medical urgency. METHODS: The recently identified SARS-CoV-2 was identified from the seafood market of the city Wuhan, China, in December 2019 and caused a global pandemic. This virus has now spread to more than 213 countries. This is the third highly pathogenic human coronavirus after SARS and MERS-CoV. The coronaviruses have RNA as genetic material and are known to have frequent recombination and mutations in their genome, which lead to the emergence and re-emergence of new virus strains and isolates with novel properties and extended hosts. The genetic mutations and suitable environmental conditions result in the emergence and re-emergence of pathogenic coronaviruses and cause a serious issue to human health and the economy globally. Lectins are the ubiquitous group of proteins that bind to glycosylated molecules. CONCLUSION: The plant lectins are known to have significant antiviral activities against coronaviruses. Additionally, the plant lectins can be used as potential therapeutics against bacteria, fungus, yeast, and protozoa. In this review, we have discussed the current status of human pathogenic coronavirus emergence and the use of plant lectins as antivirals against SARS-CoV-2.


Assuntos
Antivirais , COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Antivirais/farmacologia , Humanos , Lectinas , SARS-CoV-2
12.
Sci Rep ; 9(1): 15458, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664073

RESUMO

Cholesterol is a critical component of membranes and a precursor for hormones and other signaling molecules. Previously, we showed that unlike astrocytes, glioblastoma cells do not downregulate cholesterol synthesis when plated at high density. In this report, we show that high cell density induces ABCA1 expression in glioblastoma cells, enabling them to get rid of excess cholesterol generated by an activated cholesterol biosynthesis pathway. Because oxysterols are agonists for Liver X Receptors (LXRs), we investigated whether increased cholesterol activates LXRs to maintain cholesterol homeostasis in highly-dense glioblastoma cells. We observed that dense cells had increased oxysterols, which activated LXRß to upregulate ABCA1. Cells with CRISPR-mediated knockdown of LXRß, but not ABCA1, had decreased cell cycle progression and cell survival, and decreased feedback repression of the mevalonate pathway in densely-plated glioma cells. LXRß gene expression poorly correlates with ABCA1 in glioblastoma patients, and expression of each gene correlates with poor patient prognosis in different prognostic subtypes. Finally, gene expression and lipidomics analyses cells revealed that LXRß regulates the expression of immune response gene sets and lipids known to be involved in immune modulation. Thus, therapeutic targeting of LXRß in glioblastoma might be effective through diverse mechanisms.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/fisiologia , Neoplasias Encefálicas/patologia , Proliferação de Células/fisiologia , Glioblastoma/patologia , Metabolismo dos Lipídeos , Receptores X do Fígado/fisiologia , Transportador 1 de Cassete de Ligação de ATP/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Colesterol/metabolismo , Glioblastoma/imunologia , Glioblastoma/metabolismo , Homeostase , Humanos , Receptores X do Fígado/metabolismo , Ácido Mevalônico/metabolismo , Transdução de Sinais , Transcrição Gênica
13.
Front Pharmacol ; 10: 904, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474862

RESUMO

microRNAs (miRNAs) are small, non-coding nucleotides that regulate diverse biological processes. Altered microRNA biosynthesis or regulation contributes to pathological processes including kidney fibrosis. Kidney fibrosis is characterized by deposition of excess extracellular matrix (ECM), which is caused by infiltration of immune cells, inflammatory cells, altered chemokines, and cytokines as well as activation and accumulation of fibroblasts in the kidney. These activated fibroblasts can arise from epithelial cells via epithelial-to-mesenchymal transition (EMT), from bone marrow-derived M2 phenotype macrophages via macrophage-to-mesenchymal transition (MMT), from endothelial cells via endothelial-to-mesenchymal transition (EndMT), from resident fibroblasts, and from bone marrow-derived monocytes and play a crucial role in fibrotic events. Disrupted microRNA biosynthesis and aberrant regulation contribute to the activation of mesenchymal programs in the kidney. miR-29 regulates the interaction between dipeptidyl peptidase-4 (DPP-4) and integrin ß1 and the associated active transforming growth factor ß (TGFß) and pro-EndMT signaling; however, miR-let-7 targets transforming growth factor ß receptors (TGFßRs) to inhibit TGFß signaling. N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) is an endogenous anti-fibrotic peptide, which is associated with fibroblast growth factor receptor 1 (FGFR1) phosphorylation and subsequently responsible for the production of miR-let-7. miR-29 and miR-let-7 family clusters participate in crosstalk mechanisms, which are crucial for endothelial cell homeostasis. The physiological level of AcSDKP is vital for the activation of anti-fibrotic mechanisms including restoration of anti-fibrotic microRNA crosstalk and suppression of profibrotic signaling by mitigating DPP-4-associated mesenchymal activation in the epithelial cells, endothelial cells, and M2 phenotype macrophages. The present review highlights recent advancements in the understanding of both the role of microRNAs in the development of kidney disease and their potential as novel therapeutic targets for fibrotic disease states.

14.
Cancers (Basel) ; 11(2)2019 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-30691162

RESUMO

Glioblastoma is a highly lethal adult brain tumor with no effective treatments. In this review, we discuss the potential to target cholesterol metabolism as a new strategy for treating glioblastomas. Twenty percent of cholesterol in the body is in the brain, yet the brain is unique among organs in that it has no access to dietary cholesterol and must synthesize it de novo. This suggests that therapies targeting cholesterol synthesis in brain tumors might render their effects without compromising cell viability in other organs. We will describe cholesterol synthesis and homeostatic feedback pathways in normal brain and brain tumors, as well as various strategies for targeting these pathways for therapeutic intervention.

15.
Virusdisease ; 29(4): 419-433, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30539044

RESUMO

Dementia is known as loss of cellular communications in the brain at a region caused by multi-factorial diseases and pathogenic infections. Approximately eighty percent reported cases of Alzheimer's disease are followed by vascular dementia. The common symptoms of dementia include memory loss, concentration problems, thinking, and language solving situations. Dementia is a multifactorial disease but based on latest research; various reports have been published describing the linkage and role of viruses, prions and miRNAs in neurodegeneration and neurodegenerative disorders resulting into dementia and due to this we selected to review and provide latest information related to dementia. MiRNAs are small non-coding RNAs carrying genetic regulatory information contributing to neurological disorders among human and animals. A prion is an infectious agent made of protein material. Recently, it has been reported that prions play a significant role in signaling processes, resulting in amyloidogenesis and neurological disorders. Viruses attack human immune system and central nervous system and affect classical pathways of neurodegenerative diseases. Comprehensive understandings of the expression profiles and activities of these miRNAs, Prions, Viruses will illuminate their roles as potential therapeutic targets in neurodegeneration and may lead to the discovery of breakthrough treatment strategies for neurodegenerative disorders and dementia. The provided information will further be significant not only in neuro-scientific research, but also in designing and development of management strategies for dementia.

16.
AIDS ; 32(16): 2269-2278, 2018 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-30005022

RESUMO

OBJECTIVES: This study investigated whether Env-mediated fusion levels of R5X4 viruses are associated with long-term survival of an infected CCR5-/- patient. DESIGN: Four R5X4 Envs were cloned from each of two infected homosexual individuals (DR and C2) homozygous for the CCR5Δ32 allele. DR is a long-term survivor chronically infected with HIV-1 and his Envs were cloned 12 years after testing HIV-infected, whereas C2 Envs were isolated 1 year after primary infection. METHODS: The current study sequenced the gp41 subunits and created hybrid Envs that contained exchanged gp41 subunits or V3 loops. The Env-mediated fusion activity of Envs was examined in cell fusion and virus infection assays. RESULTS: Sequence analysis indicated novel polymorphisms in the gp41 subunits of C2 and DR, and revealed sequence homology between DR and certain long-term nonprogressors. The DR Envs consistently showed lower Env-mediated fusion, smaller size, and delayed onset of syncytia formation. Envs containing swapped gp41 regions resulted in the transfer of most of the fusion phenotype and in the shift of the inhibition concentration 50 (IC50) of the inhibitory T20 peptide. In contrast, Envs with swapped V3 domains resulted in the partial transfer of the fusion phenotype and no significant change in the IC50 of T20. CONCLUSIONS: Env sequence polymorphisms identified two distinct fusion phenotypes isolated from infected CCR5-/- patients. Swapping experiments confirmed DR's low fusion phenotype. Env-mediated fusion is a critical factor among others contributing to long-term survival.


Assuntos
Infecções por HIV/patologia , Sobreviventes de Longo Prazo ao HIV , HIV-1/genética , HIV-1/isolamento & purificação , Receptores CCR5/deficiência , Internalização do Vírus , Proteína gp41 do Envelope de HIV/genética , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Masculino , Polimorfismo Genético , Análise de Sequência de DNA
17.
Rice (N Y) ; 11(1): 25, 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-29671092

RESUMO

BACKGROUND: In cereal crops, stem lodging can be classified into two types: stem-breaking type and stem-bending type. To improve stem-lodging resistance, the strong culm traits of superior lodging-resistant varieties must be characterized. The identification of quantitative trait loci (QTLs) and the corresponding genes associated with the parameters for bending moment at breaking (M) and flexural rigidity (FR) is expected to enable the efficient development of lodging-resistant varieties. A set of Chromosome Segment Substitution Lines (CSSLs) derived from the cross between Takanari and Koshihikari were used in this study to identify QTLs associated with lodging resistance. RESULTS: The indica variety Takanari possesses large M due to its large section modulus (SM) despite its small bending stress (BS), whereas Takanari also has large FR due to its large secondary moment of inertia (SMI) and Young's modulus (YM). The QTLs for BS were assigned to chromosomes 3, 5, 6, 8, 9, 10, 11, and 12. Koshihikari alleles increased BS in these QTLs. The YM was increased by substitution of the Koshihikari chromosomal segments on chromosomes 2, 10, and 11. Other QTLs mapped to chromosomes 7 and 12, such that the Koshihikari alleles contributed to the decrease of YM. QTLs for cellulose density were assigned to chromosomes 1, 3, and 5, which were replaced by substitutions of Koshihikari segments. The QTLs for hemicellulose, cellulose, and holocellulose densities identified on chromosome 5 overlapped with those for BS, indicating the positive effect of the Koshihikari segment on increasing BS. CONCLUSIONS: These results suggested that the QTLs for the densities of cell wall materials in japonica varieties contributed to increased BS and might be utilized for improving lodging resistance in indica varieties of rice.

18.
CNS Neurol Disord Drug Targets ; 17(2): 78-86, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29422006

RESUMO

BACKGROUND & OBJECTIVE: The link between Zika Virus (ZIKV) epidemic and neurological disorder has raised an urgent global alarm. The current epidemic of ZIKV has triggered quick responses in the scientific world. The first case of ZIKV was reported in 2015 from Brazil and now has spread over 30 countries. Nearly four hundred cases of traveler associated ZIKV infection have also been reported in the United States. ZIKV is primarily transmitted by mosquito belonging to the genus Aedes that are widely distributed throughout the world. Additionally, the virus can also be transmitted from male to female by sexual contact. The epidemiological investigations during the current outbreak found a causal link between infection in pregnant women and the development of microcephaly (MCPH) in their unborn babies. This finding is a cause of grave concern since MCPH is a serious neural developmental disorder that can lead to significant post-natal developmental abnormalities and disabilities. Recently, published data indicates that ZIKV infection severely affects the growth of fetal neural progenitor cells and cerebral neurons resulting in malformation of cerebral cortex leading to MCPH. Recently, it has been reported that ZIKV infection deregulates the signaling pathway of neuronal cell and inhibits the neurogenesis. CONCLUSION: In this review, we discussed the information about cellular and molecular mechanisms of neurodegeneration of human neuronal cells and inhibition of neurogenesis. The provided information in this review will be very useful further not only in neuro-scientific research but also in the desig and development of management strategies for MCPH and other mosquito-borne diseases.


Assuntos
Degeneração Neural/fisiopatologia , Neurogênese , Infecção por Zika virus/patologia , Infecção por Zika virus/fisiopatologia , Humanos , Microcefalia/prevenção & controle
19.
J Neurochem ; 143(6): 671-683, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28833137

RESUMO

Elevated expression of enhancer of zeste homolog 2 (EZH2), a histone H3K27 methyltransferase, was observed in gliomas harboring telomerase reverse transcriptase (TERT) promoter mutations. Given the known involvement of TERT and EZH2 in glioma progression, the correlation between the two and subsequently its involvement in metabolic programming was investigated. Inhibition of human telomerase reverse transcriptase either pharmacologically or through genetic manipulation not only decreased EZH2 expression, but also (i) abrogated FASN levels, (ii) decreased de novo fatty acid accumulation, and (iii) increased ataxia-telangiectasia-mutated (ATM) phosphorylation levels. Conversely, diminished TERT and FASN levels upon siRNA-mediated EZH2 knockdown indicated a positive correlation between TERT and EZH2. Interestingly, ATM kinase inhibitor rescued TERT inhibition-mediated decrease in FASN and EZH2 levels. Importantly, TERT promoter mutant tumors exhibited greater microsatellite instability, heightened FASN levels and lipid accumulation. Coherent with in vitro findings, pharmacological inhibition of TERT by costunolide decreased lipid accumulation and elevated ATM expression in heterotypic xenograft glioma mouse model. By bringing TERT-EZH2 network at the forefront as driver of dysregulated metabolism, our findings highlight the non-canonical but distinct role of TERT in metabolic reprogramming and DNA damage responses in glioblastoma.


Assuntos
Dano ao DNA/fisiologia , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Glioblastoma/metabolismo , Metabolismo dos Lipídeos/fisiologia , Telomerase/metabolismo , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/fisiologia , Glioblastoma/patologia , Xenoenxertos , Humanos , Camundongos , Camundongos Nus
20.
J Mol Med (Berl) ; 95(11): 1215-1226, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28840260

RESUMO

Gangliogliomas (GGs) are the most commonly diagnosed long-term epilepsy-associated tumors (LEATs). Although molecular characterizations of brain tumors have identified few novel biomarkers among the LEATs, mechanisms of pathogenesis remain poorly understood. In this study, global microarray-based microRNA (miRNA) expression profile on a set of 9 GGs indicated 66 miRNAs to be differentially expressed in GG as compared to normal brain. The differences validated by qRT-PCR indicated microRNA-217 to be the most downregulated. Through insilico analysis, ERK1/2 and casein kinase (CK-2α) were predicted to be miR-217 regulated. As decreased miR-217 expression was concomitant with upregulated ERK1/2 and CK-2α levels in GG; the interplay between these molecules was investigated in primary human neural precursor cells to mimic the glioneuronal characteristics of these tumors. miR-217 over-expression-mediated decrease in pERK, CK-2α, and mGluR1 levels was accompanied with increase in glycogen accumulation. Importantly, increase in miR-217 levels upon CK-2α inhibition indicated inverse correlation between the two. Inhibition of CK-2α also decreased ERK and mGluR1 levels. By demonstrating, for the first time, the existence of miR-217-CK-2 cross talk and its effects on known epileptogenic factors, these findings provide a unique insight into the pathogenesis of ganglioglioma. By highlighting the role of CK-2 in affecting miR-217/ERK/mGluR1 interplay, this study suggests that targeting CK-2 may afford a novel strategy aimed at LEATs. KEY MESSAGES: Global microarray of ganglioglioma indicates downregulation of miR-217. Decreased miR-217 expression is concomitant with elevated CK-2α and Erk levels. Inverse correlation between miR-217 and CK-2α in primary human neural precursors. miR-217 agomir or CK-2α inhibition decreases pERK and mGluR1 levels. CK-2α affects miR-217/ERK/mGluR1 interplay in long-term epilepsy-associated tumors.


Assuntos
Caseína Quinase II/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Ganglioglioma/genética , Ganglioglioma/metabolismo , MicroRNAs/genética , Interferência de RNA , Caseína Quinase II/metabolismo , Linhagem Celular Tumoral , Análise por Conglomerados , Ganglioglioma/patologia , Perfilação da Expressão Gênica , Glicogênio/metabolismo , Humanos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Células-Tronco Neurais/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais , Transcriptoma
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