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1.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38752857

RESUMO

Avian reoviruses continue to cause disease in turkeys with varied pathogenicity and tissue tropism. Turkey enteric reovirus has been identified as a causative agent of enteritis or inapparent infections in turkeys. The new emerging variants of turkey reovirus, tentatively named turkey arthritis reovirus (TARV) and turkey hepatitis reovirus (THRV), are linked to tenosynovitis/arthritis and hepatitis, respectively. Turkey arthritis and hepatitis reoviruses are causing significant economic losses to the turkey industry. These infections can lead to poor weight gain, uneven growth, poor feed conversion, increased morbidity and mortality and reduced marketability of commercial turkeys. To combat these issues, detecting and classifying the types of reoviruses in turkey populations is essential. This research aims to employ clustering methods, specifically K-means and Hierarchical clustering, to differentiate three types of turkey reoviruses and identify novel emerging variants. Additionally, it focuses on classifying variants of turkey reoviruses by leveraging various machine learning algorithms such as Support Vector Machines, Naive Bayes, Random Forest, Decision Tree, and deep learning algorithms, including convolutional neural networks (CNNs). The experiments use real turkey reovirus sequence data, allowing for robust analysis and evaluation of the proposed methods. The results indicate that machine learning methods achieve an average accuracy of 92%, F1-Macro of 93% and F1-Weighted of 92% scores in classifying reovirus types. In contrast, the CNN model demonstrates an average accuracy of 85%, F1-Macro of 71% and F1-Weighted of 84% scores in the same classification task. The superior performance of the machine learning classifiers provides valuable insights into reovirus evolution and mutation, aiding in detecting emerging variants of pathogenic TARVs and THRVs.


Assuntos
Aprendizado de Máquina , Orthoreovirus Aviário , Infecções por Reoviridae , Perus , Animais , Orthoreovirus Aviário/genética , Orthoreovirus Aviário/classificação , Orthoreovirus Aviário/patogenicidade , Perus/virologia , Infecções por Reoviridae/virologia , Doenças das Aves Domésticas/virologia , Filogenia
2.
J Neurooncol ; 167(1): 189-198, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38265748

RESUMO

INTRODUCTION: CDKN2A/B homozygous deletion is one of the defining features of grade 4 in IDH-mutant astrocytic tumours. AIM: To evaluate CDKN2A/B-deletion in IDH-mutant astrocytic tumours and its clinicopathological impact. MATERIALS AND METHODS: CDKN2A/B-deletion was evaluated by Fluorescence in-situ hybridisation (FISH) and interpreted by two recently accepted methods. RESULTS: Eighty-three out of 94 cases (histologically-grade 2: 3, grade 3: 46, grade 4: 34) were interpretable on FISH. Concordant CDKN2A/B-deletion was observed in 71% (27/38) of lower-grade tumours (n = 49) and 90% (27/30) of histological grade 4 tumours (n = 34). Both the interpretation methods showed good agreement (Kappa = 0.75). CDKN2A/B-deletion showed an inverse correlation for < 10% MIB-1 labeling index (p = 0.01) while that by method-2 showed a significant correlation for grade 4 (p = 0.02). No significant correlation was observed for any other clinicopathological parameters. Twenty-four patients showed progression/recurrence (including deaths), and no significant difference in frequency of CDKN2A/B deletion was observed among cases with disease progression across different histological grades. CONCLUSIONS: CDKN2A/B-deletion was observed across all the histological grades of IDH-mutant astrocytic tumours, expectedly more in the higher grade. FISH, as a method, can be used for the detection of CDKN2A/B homozygous deletion, when there is concordant interpretation.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Humanos , Astrocitoma/genética , Astrocitoma/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Fluorescência , Homozigoto , Isocitrato Desidrogenase/genética , Mutação , Deleção de Sequência , Inibidor de Quinase Dependente de Ciclina p15/genética
3.
Vet Pathol ; : 3009858241235392, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38440886

RESUMO

Three cats, aged 2 to 11 years, presented to the University of Minnesota Veterinary Diagnostic Laboratory over a 3-year period following euthanasia or death due to respiratory distress. Thoracic radiographs revealed nodular, soft tissue opacities throughout the lung fields in all cases. On postmortem examination, approximately 60% to 80% of the lung parenchyma were expanded by multifocal to coalescing, well-demarcated, beige, semi-firm nodules. Histologically, large numbers of neutrophils, fewer macrophages, fibrin, and cellular and karyorrhectic debris effaced the pulmonary parenchyma. The inflammatory foci contained aggregates of gram-negative cocci. 16s rRNA Sanger sequencing and whole-genome sequencing identified the bacteria isolated from the lung of all cats under aerobic conditions as a novel Neisseria spp. Based on whole-genome sequence analysis, all 3 sequences shared 92.71% and 92.67% average nucleotide identity with closely related Neisseria animaloris NZ LR134440T and Neisseria animaloris GCA 002108605T, respectively. The in silico DNA-DNA hybridization identity compared to our isolates was 46.6% and 33.8% with strain DSM Neisseria zoodegmatis 21642 and strain DSM 21643, respectively. All 3 sequences have less than 95% average nucleotide identity and less than 70% DNA-DNA hybridization identity, suggesting that the 3 isolates are a novel species of the genus Neisseria. Infection with Neisseria spp. induces an embolic pneumonia in cats that radiographically and pathologically resembles a metastatic neoplastic process and should be considered among the etiologic differential diagnoses in cases of infectious pulmonary disease with a disseminated, nodular lung pattern.

4.
PLoS Pathog ; 17(8): e1009902, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34460869

RESUMO

The p21-activated kinase (PAK) family regulate a multitude of cellular processes, including actin cytoskeleton remodelling. Numerous bacterial pathogens usurp host signalling pathways that regulate actin reorganisation in order to promote Infection. Salmonella and pathogenic Escherichia coli drive actin-dependent forced uptake and intimate attachment respectively. We demonstrate that the pathogen-driven generation of both these distinct actin structures relies on the recruitment and activation of PAK. We show that the PAK kinase domain is dispensable for this actin remodelling, which instead requires the GTPase-binding CRIB and the central poly-proline rich region. PAK interacts with and inhibits the guanine nucleotide exchange factor ß-PIX, preventing it from exerting a negative effect on cytoskeleton reorganisation. This kinase-independent function of PAK may be usurped by other pathogens that modify host cytoskeleton signalling and helps us better understand how PAK functions in normal and diseased eukaryotic cells.


Assuntos
Actinas/química , Citoesqueleto/química , Infecções por Salmonella/microbiologia , Salmonella enterica/fisiologia , Quinases Ativadas por p21/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Fosforilação , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Fatores de Troca de Nucleotídeo Guanina Rho/metabolismo , Infecções por Salmonella/metabolismo , Infecções por Salmonella/patologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Quinases Ativadas por p21/genética
5.
Clin Infect Dis ; 75(1): e368-e379, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35323932

RESUMO

BACKGROUND: In locations where few people have received coronavirus disease 2019 (COVID-19) vaccines, health systems remain vulnerable to surges in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Tools to identify patients suitable for community-based management are urgently needed. METHODS: We prospectively recruited adults presenting to 2 hospitals in India with moderate symptoms of laboratory-confirmed COVID-19 to develop and validate a clinical prediction model to rule out progression to supplemental oxygen requirement. The primary outcome was defined as any of the following: SpO2 < 94%; respiratory rate > 30 BPM; SpO2/FiO2 < 400; or death. We specified a priori that each model would contain three clinical parameters (age, sex, and SpO2) and 1 of 7 shortlisted biochemical biomarkers measurable using commercially available rapid tests (C-reactive protein [CRP], D-dimer, interleukin 6 [IL-6], neutrophil-to-lymphocyte ratio [NLR], procalcitonin [PCT], soluble triggering receptor expressed on myeloid cell-1 [sTREM-1], or soluble urokinase plasminogen activator receptor [suPAR]), to ensure the models would be suitable for resource-limited settings. We evaluated discrimination, calibration, and clinical utility of the models in a held-out temporal external validation cohort. RESULTS: In total, 426 participants were recruited, of whom 89 (21.0%) met the primary outcome; 257 participants comprised the development cohort, and 166 comprised the validation cohort. The 3 models containing NLR, suPAR, or IL-6 demonstrated promising discrimination (c-statistics: 0.72-0.74) and calibration (calibration slopes: 1.01-1.05) in the validation cohort and provided greater utility than a model containing the clinical parameters alone. CONCLUSIONS: We present 3 clinical prediction models that could help clinicians identify patients with moderate COVID-19 suitable for community-based management. The models are readily implementable and of particular relevance for locations with limited resources.


Assuntos
COVID-19 , Adulto , COVID-19/diagnóstico , Progressão da Doença , Humanos , Interleucina-6 , Modelos Estatísticos , Alta do Paciente , Segurança do Paciente , Prognóstico , Estudos Prospectivos , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Reprodutibilidade dos Testes , SARS-CoV-2
6.
RNA Biol ; 19(1): 26-43, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34895045

RESUMO

Igf2bp1 is an oncofetal RNA binding protein whose expression in numerous types of cancers is associated with upregulation of key pro-oncogenic RNAs, poor prognosis, and reduced survival. Importantly, Igf2bp1 synergizes with mutations in Kras to enhance signalling and oncogenic activity, suggesting that molecules inhibiting Igf2bp1 could have therapeutic potential. Here, we isolate a small molecule that interacts with a hydrophobic surface at the boundary of Igf2bp1 KH3 and KH4 domains, and inhibits binding to Kras RNA. In cells, the compound reduces the level of Kras and other Igf2bp1 mRNA targets, lowers Kras protein, and inhibits downstream signalling, wound healing, and growth in soft agar, all in the absence of any toxicity. This work presents an avenue for improving the prognosis of Igf2bp1-expressing tumours in lung, and potentially other, cancer(s).


Assuntos
Antineoplásicos/farmacologia , Carcinogênese/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas de Ligação a RNA/antagonistas & inibidores , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Ensaios de Triagem em Larga Escala , Humanos , Ligação Proteica/efeitos dos fármacos , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Indian J Microbiol ; 62(4): 627-633, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36458219

RESUMO

This study reports a rare fatal case of Chromobacterium violeceum OUAT_2017 strain infection in an Asiatic elephant calf in India. Necropsy revealed pus-filled nodules in liver, spleen, and lungs. Nutrient broth cultures of nodule content showed sediment of violet pigment whereas smooth, non-diffusible, violet-pigmented, homogeneous colonies appeared on nutrient agar. The organism was found to be non-haemolytic and resistant to 8 of the 24 antibiotics tested in vitro. Partial 16S rRNA gene sequence measuring 1410 bp revealed 97% homology with C. violeceum. The bacterial genome composed of 64.87% of G + C content with total size of 4,681,202 bp. The genome annotation has 42 genes responsible for multidrug antibiotic resistance with the presence of Aminoglycoside-modifying enzymes (AAC (6')) that targets streptomycin and spectinomycin. Our findings corroborated the lethal effect of C. violeceum in a new host (elephant) that enriched scientific information on epidemiological picture and whole genome sequencing as well. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-022-01047-4.

8.
J Biol Chem ; 295(25): 8602-8612, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32385106

RESUMO

Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) is an mRNA-binding protein that has an oncofetal pattern of expression. It is also expressed in intestinal tissue, suggesting that it has a possible role in intestinal homeostasis. To investigate this possibility, here we generated Villin CreERT2:Igf2bp1flox/flox mice, which enabled induction of an IGF2BP1 knockout specifically in intestinal epithelial cells (IECs) of adult mice. Using gut barrier and epithelial permeability assays and several biochemical approaches, we found that IGF2BP1 ablation in the adult intestinal epithelium causes mild active colitis and mild-to-moderate active enteritis. Moreover, the IGF2BP1 deletion aggravated dextran sodium sulfate-induced colitis. We also found that IGF2BP1 removal compromises barrier function of the intestinal epithelium, resulting from altered protein expression at tight junctions. Mechanistically, IGF2BP1 interacted with the mRNA of the tight-junction protein occludin (Ocln), stabilizing Ocln mRNA and inducing expression of occludin in IECs. Furthermore, ectopic occludin expression in IGF2BP1-knockdown cells restored barrier function. We conclude that IGF2BP1-dependent regulation of occludin expression is an important mechanism in intestinal barrier function maintenance and in the prevention of colitis.


Assuntos
Ocludina/metabolismo , Permeabilidade , Proteínas de Ligação a RNA/metabolismo , Animais , Linhagem Celular , Colite/induzido quimicamente , Colite/mortalidade , Colite/patologia , Colo/patologia , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ocludina/genética , Ligação Proteica , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteínas de Ligação a RNA/genética , Índice de Gravidade de Doença , Taxa de Sobrevida , Proteínas de Junções Íntimas/metabolismo , Regulação para Cima
9.
Microb Ecol ; 81(4): 1042-1053, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33244619

RESUMO

Host-associated microbiota play a critical role in host fitness by providing nutrition, enhancing digestion capabilities, and by providing protection from pathogens. Here, we investigated the effects of two environmental stressors, temperature, and salinity, on the microbiota associated with zebra mussels (ZMs), a highly invasive bivalve in North America. To examine this in detail, lake-collected ZMs were acclimated to laboratory conditions, and subjected to temperature and salinity stress conditions. The impact of these stressors on the diversity, composition, and dynamics of ZM-associated microbiota were assessed by using amplicon- and shotgun-based sequencing, and qPCR-based approaches. Elevated temperature was found to be the primary driver of ZM mortality, although salinity alone also increased its likelihood. Stressor-induced ZM mortality, which ranged between 53 and 100%, was concomitant with significant increases in the relative abundance of several genera of putative opportunistic pathogens including Aeromonas. These genera were only present in low relative abundance in ZMs obtained from the control tank with 0% mortality. Shotgun sequencing and qPCR analyses indicated that the relative and absolute abundances of pathogenic Aeromonas species (particularly A. veronii) were significantly greater in temperature-induced dead ZMs. Taken together, our results show that environmental stress, especially elevated temperature (> 25 °C), is associated with the rapid mortality of ZMs as well as the proliferation of putative opportunistic bacterial pathogens.


Assuntos
Bivalves , Dreissena , Microbiota , Animais , Lagos , Temperatura
10.
Mol Biol Rep ; 48(6): 5371-5376, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34232463

RESUMO

BACKGROUND: Enterococci are ubiquitous microorganisms having diverse ecological niches but most prominently in gastrointestinal tract of humans and animals. Production of enterocins makes them a good probiotic candidate. However, their role as probiotics has become ambiguous in the last few years because of the presence of virulence factors and antibiotic resistance genes. These virulence traits are known to be transferred genetically, which makes them opportunistic pathogens in the gastrointestinal tract leading to serious concerns about their being used as probiotics. In the present study, Enterococcusspp. isolated from the human gut were subjected to Whole-Genome Sequencing (WGS) to determine the presence of resistance and virulence genes. METHODS AND RESULTS: Four human origins Enterococcus spp. including Enterococcus faecalis, Enterococcus casseliflavus, and two Enterococcus gallinarum were isolated from human fecal samples and further cultured on blood agar. Sanger sequencing was done using Applied Biosystems 3730xl DNA Analyzer. These strains were further subjected to WGS using oxford nanopore technology MinION. Raw data were analyzed using the free online tool epi2me. The Comprehensive Antibiotic Resistance Database (CARD) and RAST (Rapid Annotation using Subsystem Technology) software were used to look for the presence of antibiotic resistance genes in these strains. Resistance determinants for clinically important antibiotics (vancomycin) and functional virulence factor genes were detected. G-view server was used for comparative genomics of all strains. CONCLUSION: The genomic sequencing of Enterococcus suggested that E. faecalis, E. casseliflavus, and E. gallinarum strains are opportunistic pathogens, having antibiotic resistance genes. All isolates had vancomycin resistance genes, which were expressed phenotypically. Genes related to bacteriocin resistance were also present in E. casseliflavus and E. gallinarum.


Assuntos
Farmacorresistência Bacteriana/genética , Enterococcus/genética , Virulência/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Enterococcus/patogenicidade , Enterococcus faecalis/genética , Fezes , Microbioma Gastrointestinal/genética , Genômica/métodos , Humanos , Testes de Sensibilidade Microbiana , Probióticos/farmacologia , Fatores de Virulência/genética , Sequenciamento Completo do Genoma/métodos
11.
Mol Microbiol ; 112(4): 1350-1369, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31441971

RESUMO

Flocculation is an essential characteristic of yeast cells required for survival under adverse conditions. The multicellular structure (flocs) of yeast provides a suitable microenvironment to enhance the chances of survival during stress conditions. Although the signaling events triggering flocculation have been studied earlier, molecular mechanisms remain elusive. In the present study, we used flocculating sen1 mutants to identify the mechanism of flocculation. Based on the abnormal cell surface morphology and constitutive phosphorylation of Slt2p in flocculating sen1 mutant cells, we hypothesized if flocculation was regulated by the cell wall integrity (CWI) pathway. Up-regulation of FLO genes in wild-type cells was observed upon the activation of CWI pathway either by chemical treatment or by deleting Slt2 phosphatase (Msg5). Our study with Slt2 mutants reveals that the active state of Slt2 is indispensable for flocculation. Deletion of either SLT2 or RLM1 leads to reduced flocculation. Furthermore, we observed overlapping binding sites for Rlm1 and Tup1 at the promoters of almost all the FLO genes. Finally, we show higher Rlm1 and lower Tup1 occupancy at the promoters of FLO1 and FLO5 in flocculating cells. Altogether we demonstrate that CWI MAPK (Slt2) pathway uses a non-catalytic mechanism to activate the transcription of FLO genes.


Assuntos
Floculação , Proteínas de Domínio MADS/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Parede Celular/metabolismo , Parede Celular/fisiologia , DNA Helicases/genética , DNA Helicases/metabolismo , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/fisiologia , Lectinas de Ligação a Manose/genética , Lectinas de Ligação a Manose/metabolismo , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Fosforilação , Regiões Promotoras Genéticas , RNA Helicases/genética , RNA Helicases/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/fisiologia , Transdução de Sinais , Ativação Transcricional
12.
Proc Natl Acad Sci U S A ; 114(15): 3915-3920, 2017 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-28348208

RESUMO

To establish infections, Salmonella injects virulence effectors that hijack the host actin cytoskeleton and phosphoinositide signaling to drive pathogen invasion. How effectors reprogram the cytoskeleton network remains unclear. By reconstituting the activities of the Salmonella effector SopE, we recapitulated Rho GTPase-driven actin polymerization at model phospholipid membrane bilayers in cell-free extracts and identified the network of Rho-recruited cytoskeleton proteins. Knockdown of network components revealed a key role for myosin VI (MYO6) in Salmonella invasion. SopE triggered MYO6 localization to invasion foci, and SopE-mediated activation of PAK recruited MYO6 to actin-rich membranes. We show that the virulence effector SopB requires MYO6 to regulate the localization of PIP3 and PI(3)P phosphoinositides and Akt activation. SopE and SopB target MYO6 to coordinate phosphoinositide production at invasion foci, facilitating the recruitment of cytoskeleton adaptor proteins to mediate pathogen uptake.


Assuntos
Interações Hospedeiro-Patógeno/fisiologia , Cadeias Pesadas de Miosina/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Salmonella typhimurium/patogenicidade , Proteínas de Bactérias/metabolismo , Membrana Celular/metabolismo , Citoesqueleto/metabolismo , Citoesqueleto/microbiologia , Células HeLa , Humanos , Proteínas dos Microfilamentos/metabolismo , Cadeias Pesadas de Miosina/genética , Fosfatidilinositóis/metabolismo , Salmonella typhimurium/metabolismo , Transdução de Sinais , Fatores de Virulência/metabolismo
13.
Sensors (Basel) ; 20(23)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33256006

RESUMO

In the Internet of Things (IoT) + Fog + Cloud architecture, with the unprecedented growth of IoT devices, one of the challenging issues that needs to be tackled is to allocate Fog service providers (FSPs) to IoT devices, especially in a game-theoretic environment. Here, the issue of allocation of FSPs to the IoT devices is sifted with game-theoretic idea so that utility maximizing agents may be benign. In this scenario, we have multiple IoT devices and multiple FSPs, and the IoT devices give preference ordering over the subset of FSPs. Given such a scenario, the goal is to allocate at most one FSP to each of the IoT devices. We propose mechanisms based on the theory of mechanism design without money to allocate FSPs to the IoT devices. The proposed mechanisms have been designed in a flexible manner to address the long and short duration access of the FSPs to the IoT devices. For analytical results, we have proved the economic robustness, and probabilistic analyses have been carried out for allocation of IoT devices to the FSPs. In simulation, mechanism efficiency is laid out under different scenarios with an implementation in Python.

14.
Int J Mol Sci ; 21(7)2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32252226

RESUMO

The small GTPase ADP-ribosylation factor 6 (Arf6) anchors at the plasma membrane to orchestrate key functions, such as membrane trafficking and regulating cortical actin cytoskeleton rearrangement. A number of studies have identified key players that interact with Arf6 to regulate actin dynamics in diverse cell processes, yet it is still unknown whether Arf6 can directly signal to the wave regulatory complex to mediate actin assembly. By reconstituting actin dynamics on supported lipid bilayers, we found that Arf6 in co-ordination with Rac1(Ras-related C3 botulinum toxin substrate 1) can directly trigger actin polymerization by recruiting wave regulatory complex components. Interestingly, we demonstrated that Arf6 triggers actin assembly at the membrane directly without recruiting the Arf guanine nucleotide exchange factor (GEF) ARNO (ARF nucleotide-binding site opener), which is able to activate Arf1 to enable WRC-dependent actin assembly. Furthermore, using labelled E. coli, we demonstrated that actin assembly by Arf6 also contributes towards efficient phagocytosis in THP-1 macrophages. Taken together, this study reveals a mechanism for Arf6-driven actin polymerization.


Assuntos
Fatores de Ribosilação do ADP/metabolismo , Actinas/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Fator 6 de Ribosilação do ADP , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Modelos Biológicos , Fagocitose/imunologia , Ligação Proteica , Células THP-1
15.
J Environ Manage ; 258: 110032, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929067

RESUMO

This study focuses on the photocatalytic degradation of quinoline, a recalcitrant heterocyclic nitrogenous aromatic organic compound, using the mixed oxide ZnO-TiO2 photo-catalyst. Photo-catalysts were synthesized by the solid-state reaction method at different calcination temperatures of 400 °C, 600 °C, and 800 °C. Different analytical methods, including Field emission scanning electron microscope, Brunauer-Emmett-Teller surface area, X-ray diffraction, UV-vis diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy analysis were used for the catalyst characterization. The highest pore surface area of 57.9 m2g-1 was obtained for the photo-catalyst calcined at 400 °C. The effects of calcination temperature, solution pH, initial concentration, catalyst dose as well as irradiation time were studied. At the optimum condition, i.e., calcination temperature of 400 °C, pH ≈8 and catalyst dose of 2.5 gL-1, maximum quinoline degradation and total organic carbon (TOC) removal efficiency of ≈92% and ≈78% were obtained after 240 min for initial quinoline amount of 50 mgL-1. The 1st, 2nd, and nth-order kinetic models were applied to analyze the quinoline degradation rate. The photocatalytic mechanism was studied by drawing energy level diagram with the help of the band-gap structures of the ZnO and TiO2, potential of the free radicals like OH and O2 and HOMO-LUMO energy gap of the quinoline molecule. The proposed pathways of quinoline mineralization were suggested on the basis of the identified intermediates by the gas chromatograph-mass spectrometer analysis and scavenger study.


Assuntos
Quinolinas , Óxido de Zinco , Catálise , Óxidos , Titânio , Difração de Raios X
17.
Microsc Microanal ; 25(6): 1383-1393, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31368426

RESUMO

GaN films have been grown on SiC substrates with an AlN nucleation layer by using a metal organic chemical vapor deposition technique. Micro-cracking of the GaN films has been observed in some of the grown samples. In order to investigate the micro-cracking and microstructure, the samples have been studied using various characterization techniques such as optical microscopy, atomic force microscopy, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy (TEM). The surface morphology of the AlN nucleation layer is related to the stress evolution in subsequent overgrown GaN epilayers. It is determined via TEM evidence that, if the AlN nucleation layer has a rough surface morphology, this leads to tensile stresses in the GaN films, which finally results in cracking. Raman spectroscopy results also suggest this, by showing the existence of considerable tensile residual stress in the AlN nucleation layer. Based on these various observations and results, conclusions or propositions relating to the microstructure are presented.

18.
Indian J Urol ; 35(1): 48-53, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30692724

RESUMO

INTRODUCTION: The optimal management of upper ureteric calculus remains controversial. We compare the outcomes of antegrade percutaneous ureterolithotripsy (APCUL) with retrograde ureteroscopic lithotripsy (URSL) for upper ureteric calculus with respect to stone clearance, morbidity, and complication rates. MATERIALS AND METHODS: This prospective study was carried out from December 2014 to June 2016. A total of 117 patients with upper ureteric calculus sized (10-20) mm who underwent APCUL or URSL were included in the study. RESULTS: APCUL and URSL were performed in 64 and 53 patients, respectively. The mean age and stone size were comparable between the two groups. The stone clearance rate at 1-month follow-up was 93.75% in the antegrade group and 81.13% in the retrograde group (P = 0.036). Mean anaesthesia time was significantly longer for the APCUL group while the actual mean operative time was significantly longer for the URSL group (P < 0.001). The overall complication rate was higher in antegrade group (P = 0.804), whereas most of the major complications (Clavien Grade III or more) occurred only in the URSL group (P = 0.007). Blood transfusion was required only in the APCUL group (7.8% versus 0%; P = 0.50). In the URSL group, stone retropulsion occurred in four patients, of which three subsequently required shock wave lithotripsy and one required percutaneous nephrolithotomy in a second sitting. CONCLUSION: APCUL has better stone-free rates as compared to URSL for an upper ureteric calculus of size 10-20 mm. Although the postoperative minor complications are higher in the antegrade group, severe complications occurred only in the retrograde group. Hence, antegrade approach can be considered as the preferred option to achieve better stone clearance in a single sitting with acceptable morbidity and complication rates.

19.
J Biol Chem ; 292(5): 1847-1864, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-27932462

RESUMO

Salmonella enterica are invasive intracellular pathogens that replicate within a membrane-bound compartment inside infected host cells known as the Salmonella-containing vacuole. How Salmonella obtains nutrients for growth within this intracellular niche despite the apparent isolation is currently not known. Recent studies have indicated the importance of glucose and related carbon sources for tissue colonization and intracellular proliferation within host cells during Salmonella infections, although none have been found to be essential. We found that wild-type Salmonella are capable of replicating within infected host cells in the absence of both exogenous sugars and/or amino acids. Furthermore, mutants defective in glucose uptake or dependent upon peptides for growth also showed no significant loss in intracellular replication, suggesting host-derived peptides can supply both carbon units and amino acids. Here, we show that intracellular Salmonella recruit the host proteins LAMP-2A and Hsc73, key components of the host protein turnover pathway known as chaperone-mediated autophagy involved in transport of cytosolic proteins to the lysosome for degradation. Host-derived peptides are shown to provide a significant contribution toward the intracellular growth of Salmonella The results reveal a means whereby intracellular Salmonella gain access to the host cell cytosol from within its membrane-bound compartment to acquire nutrients. Furthermore, this study provides an explanation as to how Salmonella evades activation of autophagy mechanisms as part of the innate immune response.


Assuntos
Autofagia , Proteínas de Choque Térmico HSC70/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Infecções por Salmonella/metabolismo , Salmonella enterica/fisiologia , Linhagem Celular Tumoral , Proteínas de Choque Térmico HSC70/genética , Humanos , Proteína 2 de Membrana Associada ao Lisossomo/genética , Infecções por Salmonella/genética
20.
Plant J ; 91(6): 1088-1107, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28640939

RESUMO

Seed development is an intricate process regulated via a complex transcriptional regulatory network. To understand the molecular mechanisms governing seed development and seed size/weight in chickpea, we performed a comprehensive analysis of transcriptome dynamics during seed development in two cultivars with contrasting seed size/weight (small-seeded, Himchana 1 and large-seeded, JGK 3). Our analysis identified stage-specific expression for a significant proportion (>13%) of the genes in each cultivar. About one half of the total genes exhibited significant differential expression in JGK 3 as compared with Himchana 1. We found that different seed development stages can be delineated by modules of coexpressed genes. A comparative analysis revealed differential developmental stage specificity of some modules between the two cultivars. Furthermore, we constructed transcriptional regulatory networks and identified key components determining seed size/weight. The results suggested that extended period of cell division during embryogenesis and higher level of endoreduplication along with more accumulation of storage compounds during maturation determine large seed size/weight. Further, we identified quantitative trait loci-associated candidate genes harboring single nucleotide polymorphisms in the promoter sequences that differentiate small- and large-seeded chickpea cultivars. The results provide a valuable resource to dissect the role of candidate genes governing seed development and seed size/weight in chickpea.


Assuntos
Cicer/genética , Redes Reguladoras de Genes , Genoma de Planta/genética , Locos de Características Quantitativas/genética , Sementes/genética , Transcriptoma , Cicer/crescimento & desenvolvimento , Polimorfismo de Nucleotídeo Único/genética , Sementes/crescimento & desenvolvimento
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