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1.
Proc Natl Acad Sci U S A ; 120(5): e2217327120, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36693102

RESUMO

Gould syndrome is a rare multisystem disorder resulting from autosomal dominant mutations in the collagen-encoding genes COL4A1 and COL4A2. Human patients and Col4a1 mutant mice display brain pathology that typifies cerebral small vessel diseases (cSVDs), including white matter hyperintensities, dilated perivascular spaces, lacunar infarcts, microbleeds, and spontaneous intracerebral hemorrhage. The underlying pathogenic mechanisms are unknown. Using the Col4a1+/G394V mouse model, we found that vasoconstriction in response to internal pressure-the vascular myogenic response-is blunted in cerebral arteries from middle-aged (12 mo old) but not young adult (3 mo old) animals, revealing age-dependent cerebral vascular dysfunction. The defect in the myogenic response was associated with a significant decrease in depolarizing cation currents conducted by TRPM4 (transient receptor potential melastatin 4) channels in native cerebral artery smooth muscle cells (SMCs) isolated from mutant mice. The minor membrane phospholipid phosphatidylinositol 4,5 bisphosphate (PIP2) is necessary for TRPM4 activity. Dialyzing SMCs with PIP2 and selective blockade of phosphoinositide 3-kinase (PI3K), an enzyme that converts PIP2 to phosphatidylinositol (3, 4, 5)-trisphosphate (PIP3), restored TRPM4 currents. Acute inhibition of PI3K activity and blockade of transforming growth factor-beta (TGF-ß) receptors also rescued the myogenic response, suggesting that hyperactivity of TGF-ß signaling pathways stimulates PI3K to deplete PIP2 and impair TRPM4 channels. We conclude that age-related cerebral vascular dysfunction in Col4a1+/G394V mice is caused by the loss of depolarizing TRPM4 currents due to PIP2 depletion, revealing an age-dependent mechanism of cSVD.


Assuntos
Músculo Liso Vascular , Canais de Cátion TRPM , Humanos , Camundongos , Animais , Pessoa de Meia-Idade , Músculo Liso Vascular/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Artérias Cerebrais/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(35): e2306479120, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37607233

RESUMO

Neurovascular coupling (NVC), a vital physiological process that rapidly and precisely directs localized blood flow to the most active regions of the brain, is accomplished in part by the vast network of cerebral capillaries acting as a sensory web capable of detecting increases in neuronal activity and orchestrating the dilation of upstream parenchymal arterioles. Here, we report a Col4a1 mutant mouse model of cerebral small vessel disease (cSVD) with age-dependent defects in capillary-to-arteriole dilation, functional hyperemia in the brain, and memory. The fundamental defect in aged mutant animals was the depletion of the minor membrane phospholipid phosphatidylinositol 4,5 bisphosphate (PIP2) in brain capillary endothelial cells, leading to the loss of inwardly rectifying K+ (Kir2.1) channel activity. Blocking phosphatidylinositol-3-kinase (PI3K), an enzyme that diminishes the bioavailability of PIP2 by converting it to phosphatidylinositol (3, 4, 5)-trisphosphate (PIP3), restored Kir2.1 channel activity, capillary-to-arteriole dilation, and functional hyperemia. In longitudinal studies, chronic PI3K inhibition also improved the memory function of aged Col4a1 mutant mice. Our data suggest that PI3K inhibition is a viable therapeutic strategy for treating defective NVC and cognitive impairment associated with cSVD.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Hiperemia , Acoplamento Neurovascular , Animais , Camundongos , Células Endoteliais , Fosfatidilinositol 3-Quinases/genética , Doenças de Pequenos Vasos Cerebrais/genética , Fosfatidilinositol 3-Quinase
3.
Environ Res ; 258: 119397, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38876419

RESUMO

Global warming and unpredictable nature possess a negative impact on fisheries and the daily activities of other habitats. GIS and remote sensing approach is an effective tool to determine the morphological characteristics of the lake. The present study addresses the interactive effect of climate and landuse changes hit on fish catch in lake fisheries. We used a combination of the landscape disturbance index, vulnerability index, and loss index to construct a complete ecological risk assessment framework based on the landscape structure of regional ecosystems. The results indicate an increase from around 45%-76% in the percentage of land susceptible to moderate to ecological severe risk in the landscape from 2004 to 2023. Since 1950, temperature changes have increased by 0.4%, precipitation has decreased by 6%, and water levels have decreased by 4.2%, based on the results. The results indicate that landuse, water temperature, precipitation, and water depth significantly impact the aquaculture system. The findings strongly suggest integrating possible consequences of environmental change on fish yield for governance modeling techniques to minimize their effects.

4.
Molecules ; 29(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276579

RESUMO

Wittig olefination at hetero-benzylic positions for electron-deficient and electron-rich heterocycles has been studied. The electronic effects of some commonly used protective groups associated with the N-heterocycles were also investigated for alkenes obtained in the context of the widely employed Wittig olefination reaction. It was observed that hetero-benzylic positions of the pyridine, thiophene and furan derivatives were stable after Wittig olefination. Similarly, electron-withdrawing groups (EWGs) attached to N-heterocycles (indole and pyrrole derivatives) directly enhanced the stability of the benzylic position during and after Wittig olefination, resulting in the formation of stable alkenes. Conversely, electron-donating group (EDG)-associated N-heterocycles boosted the reactivity of benzylic alkene, leading to lower yields or decomposition of the olefination products.

5.
Hum Mol Genet ; 29(21): 3532-3545, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33105486

RESUMO

Gliomas have substantial mortality to incidence rate ratio and a dismal clinical course. Newer molecular insights, therefore, are imperative to refine glioma diagnosis, prognosis and therapy. Meningioma 1 (MN1) gene is a transcriptional co-regulator implicated in other malignancies, albeit its significance in glioma pathology remains to be explored. IGFBP5 is regulated transcriptionally by MN1 and IGF1 and is associated with higher glioma grade and shorter survival time, prompting us to ascertain their correlation in these tumors. We quantified the expression of MN1, IGFBP5 and IGF1 in 40 glioma samples and examined their interrelatedness. MN1 mRNA-protein inter-correlation and the gene's copy number were evaluated in these tumors. Publicly available TCGA datasets were used to examine the association of MN1 expression levels with patient survival and for validating our findings. We observed MN1 overexpression correlated with low-grade (LGGs) and not high-grade gliomas and is not determined by the copy number alteration of the gene. Notably, gliomas with upregulated MN1 have better overall survival (OS) and progression-free survival (PFS). IGFBP5 expression associated inversely with MN1 expression levels in gliomas but correlated positively with IGF1 expression in only LGGs. This suggests a potential grade-specific interplay between repressive and activating roles of MN1 and IGF1, respectively, in the regulation of IGFBP5. Thus, MN1 overexpression, a promising predictor of OS and PFS in gliomas, may serve as a prognostic biomarker in clinical practice to categorize patients with survival advantage.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/mortalidade , Variações do Número de Cópias de DNA , Regulação Neoplásica da Expressão Gênica , Glioma/mortalidade , Transativadores/genética , Proteínas Supressoras de Tumor/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Progressão da Doença , Seguimentos , Glioma/genética , Glioma/patologia , Glioma/cirurgia , Humanos , Gradação de Tumores , Taxa de Sobrevida
6.
J Org Chem ; 88(19): 14033-14047, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37712931

RESUMO

The direct and selective conversion of a C-H bond into a C-Se bond remains a significant challenge, which is even more intricate with substrates having an innate regioselectivity under several reaction conditions, such as chalcogenophenes. We overrode their selectivity toward selanylation using palladium, copper, and the 2-(methylthio)amide directing group. This chelation-assisted direct selanylation was also suitable for mono and double ortho functionalization of arenes. The mechanistic studies indicate high-valent Pd(IV) species in the catalytic cycle, a reversible C-H activation step, and Cu(II) as a sequestering agent for organoselenide byproducts.

7.
Proc Natl Acad Sci U S A ; 117(48): 30775-30786, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33199609

RESUMO

TRPML1 (transient receptor potential mucolipin 1) is a Ca2+-permeable, nonselective cation channel that is predominantly localized to the membranes of late endosomes and lysosomes (LELs). Intracellular release of Ca2+ through TRPML1 is thought to be pivotal for maintenance of intravesicular acidic pH as well as the maturation, fusion, and trafficking of LELs. Interestingly, genetic ablation of TRPML1 in mice (Mcoln1-/- ) induces a hyperdistended/hypertrophic bladder phenotype. Here, we investigated this phenomenon further by exploring an unconventional role for TRPML1 channels in the regulation of Ca2+-signaling activity and contractility in bladder and urethral smooth muscle cells (SMCs). Four-dimensional (4D) lattice light-sheet live-cell imaging showed that the majority of LELs in freshly isolated bladder SMCs were essentially immobile. Superresolution microscopy revealed distinct nanoscale colocalization of LEL-expressing TRPML1 channels with ryanodine type 2 receptors (RyR2) in bladder SMCs. Spontaneous intracellular release of Ca2+ from the sarcoplasmic reticulum (SR) through RyR2 generates localized elevations of Ca2+ ("Ca2+ sparks") that activate plasmalemmal large-conductance Ca2+-activated K+ (BK) channels, a critical negative feedback mechanism that regulates smooth muscle contractility. This mechanism was impaired in Mcoln1-/- mice, which showed diminished spontaneous Ca2+ sparks and BK channel activity in bladder and urethra SMCs. Additionally, ex vivo contractility experiments showed that loss of Ca2+ spark-BK channel signaling in Mcoln1-/- mice rendered both bladder and urethra smooth muscle hypercontractile. Voiding activity analyses revealed bladder overactivity in Mcoln1-/- mice. We conclude that TRPML1 is critically important for Ca2+ spark signaling, and thus regulation of contractility and function, in lower urinary tract SMCs.


Assuntos
Canais de Cálcio/metabolismo , Cálcio/metabolismo , Contração Muscular , Músculo Liso/metabolismo , Miócitos de Músculo Liso/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Fenômenos Fisiológicos do Sistema Urinário , Animais , Biomarcadores , Imunofluorescência , Expressão Gênica , Espaço Intracelular/metabolismo , Masculino , Potenciais da Membrana , Camundongos , Camundongos Knockout , Contração Muscular/genética , Transporte Proteico , Canais de Potencial de Receptor Transitório/genética , Bexiga Urinária/metabolismo , Bexiga Urinária/fisiopatologia
8.
Reg Environ Change ; 23(1): 33, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36776962

RESUMO

Given the agricultural demand to supply animals with food, the scope of today's soybean production and international trade can influence the nitrogen cycle. Rather than using soybeans from within the region of animal production, animal producers import nutritional supplements from distant growers. This widely opens the biogeochemical cycle of nitrogen, which reduces local recycling and increases carriage of reactive nitrogen via the supply chain. Ultimately, this potentiates the effects of a "nitrogen cascade" process. This study estimates nitrogen flows for Brazilian soybean transported to feed European livestock and attempts to quantify the understanding of how this flow can impact the nitrogen cascade effect. The hypothesis is that the growing trade of Brazilian soybean products is sufficient to spike reactive nitrogen production that can potentially cause distant environmental impacts of the nitrogen cascade. In this respect, the estimation of the nitrogen flows was evaluated using material flow analysis, and the cascade effect was quantified by means of a nitrogen cascade indicator (NCI). Notably, NCI can calculate the released amount of nitrogen in the environment along the entire supply chain of livestock products. NCI-based evaluation of Brazilian soybean products consumed by European livestock indicated the accumulation of nitrogen levels. There was also an increase in nitrogen flows in the Brazilian phase (0.058 Gg in 2007 to 139.86 Gg in 2019 for soybean meal; 584.28 Gg in 2007 to 309.78 Gg in 2019 for soybeans) accompanying a stability in European livestock production. This highlights the necessity for adjustments in nitrogen circularity between all levels of food production and improved strategies of more localised feed autonomy for sustainable global development. Supplementary Information: The online version contains supplementary material available at 10.1007/s10113-023-02034-1.

9.
Molecules ; 27(16)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36014345

RESUMO

An ancient saffron-based polyherbal formulation, Dawa-ul-Kurkum (DuK), has been used to treat liver ailments and other diseases and was recently evaluated for its anticancer potential against hepatocellular carcinoma (HCC) by our research team. To gain further insight into the lead molecule of DuK, we selected ten active constituents belonging to its seven herbal constituents (crocin, crocetin, safranal, jatamansone, isovaleric acid, cinnamaldehyde, coumaric acid, citral, guggulsterone and dehydrocostus lactone). We docked them with 32 prominent proteins that play important roles in the development, progression and suppression of HCC and those involved in endoplasmic reticulum (ER) stress to identify the binding interactions between them. Three reference drugs for HCC (sorafenib, regorafenib, and nivolumab) were also examined for comparison. The in silico studies revealed that, out of the ten compounds, three of them-viz., Z-guggulsterone, dehydrocostus lactone and crocin-showed good binding efficiency with the HCC and ER stress proteins. Comparison of binding affinity with standard drugs was followed by preliminary in vitro screening of these selected compounds in human liver cancer cell lines. The results provided the basis for selecting Z-guggulsterone as the best-acting phytoconstituent amongst the 10 studied. Further validation of the binding efficiency of Z-guggulsterone was undertaking using molecular dynamics (MD) simulation studies. The effects of Z-guggulsterone on clone formation and cell cycle progression were also assessed. The anti-oxidant potential of Z-guggulsterone was analyzed through DPPH and FRAP assays. qRTPCR was utilized to check the results at the in vitro level. These results indicate that Z-guggulsterone should be considered as the main constituent of DuK instead of the crocin in saffron, as previously hypothesized.


Assuntos
Carcinoma Hepatocelular , Crocus , Neoplasias Hepáticas , Pregnenodionas , Carcinoma Hepatocelular/metabolismo , Humanos , Neoplasias Hepáticas/patologia , Pregnenodionas/farmacologia
10.
J Biol Regul Homeost Agents ; 35(3): 865-880, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34042415

RESUMO

Human Coronavirus (CoV) infections, including SARS-COV, MERS-COV, and SARS-CoV-2, usually cause fatal lower and upper respiratory tract infections due to exacerbated expression of pro-inflammatory cytokines and chemokines. We aim to summarize different aspects, such as CoV immune evasion mechanisms and host innate immune response to these infections, and their role in pathogenesis. We have also elaborated the up-to-date findings on different vaccine development strategies and progress against CoVs in both humans and non-human models. Most importantly, we have described the Phageome-human immune interaction, its therapeutic usage as anti-viral, anti-inflammatory agent, and implications for multiple vaccine development systems. The data suggest that endogenous phages might play a vital role in eliminating the infection and regulating the body's immune system. Considering the innate-immune-induced pathogenesis against CoVs and the therapeutic aptitude of phageome, we propose that the prophylactic administration of phages and phage-based vaccines could be a useful strategy to control the emerging CoV infections.


Assuntos
COVID-19 , Viroma , Humanos , Imunidade Inata , SARS-CoV-2 , Vacinação
11.
J Nat Prod ; 84(6): 1707-1714, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34110831

RESUMO

Maytenus ilicifolia or "Espinheira-Santa" is a renowned Brazilian medicinal plant usually used against intestinal and stomach ulcers. Other species with similar thorny leaves have raised great confusion in order to discern the authentic M. ilicifolia. Misidentifications can lead to product adulteration of authentic M. ilicifolia with other species, which can be found on the Brazilian market. The intake of misclassified herbal products potentially could be fatal, demanding faster reliable fingerprinting-based classification methods. In this study, the use of 1H HR-MAS NMR metabolomics fingerprinting and principal component analysis (PCA) allowed an evaluation of the authenticity for both collected and commercial M. ilicifolia samples, from the content of the flavanol, (-)-epicatechin (2), by observing variations in metabolic patterns. Plant specimen types from cultivated and natural habitats were analyzed by considering seasonal and topological differences. The interand intraplant topological metabolic profiles were found to be affected by seasonal and/or ecological trends such as sunlight, shade, rain, and the presence of pathogens. Moreover, several commercial samples, labeled as M. ilicifolia, were evaluated, but most of these products were of an inadequate quality.


Assuntos
Maytenus/química , Metaboloma , Brasil , Catequina/análise , Meio Ambiente , Folhas de Planta/química , Plantas Medicinais/química , Estações do Ano
12.
Curr Top Membr ; 85: 119-150, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32402637

RESUMO

The Ca2+-permeable, non-selective cation channel, TRPA1 (transient receptor potential ankyrin 1), is the sole member of the ankyrin TRP subfamily. TRPA1 channels are expressed on the plasma membrane of neurons as well as non-neuronal cell types, such as vascular endothelial cells. TRPA1 is activated by electrophilic compounds, including dietary molecules such as allyl isothiocyanate, a derivative of mustard. Endogenously, the channel is thought to be activated by reactive oxygen species and their metabolites, such as 4-hydroxynonenal (4-HNE). In the context of the vasculature, activation of TRPA1 channels results in a vasodilatory response mediated by two distinct mechanisms. In the first instance, TRPA1 is expressed in sensory nerves of the vasculature and, upon activation, mediates release of the potent dilator, calcitonin gene-related peptide (CGRP). In the second, work from our laboratory has demonstrated that TRPA1 is expressed in the endothelium of blood vessels exclusively in the cerebral vasculature, where its activation produces a localized Ca2+ signal that results in dilation of cerebral arteries. In this chapter, we provide an in-depth overview of the biophysical and pharmacological properties of TRPA1 channels and their importance in regulating vascular tone.


Assuntos
Vasos Sanguíneos/metabolismo , Canal de Cátion TRPA1/metabolismo , Animais , Vasos Sanguíneos/citologia , Vasos Sanguíneos/fisiologia , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Humanos
13.
Sensors (Basel) ; 20(7)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230870

RESUMO

Wireless Sensor Networks (WSNs) consist of multiple sensor nodes, each of which has the ability to collect, receive and send data. However, irregular data sources can lead to severe network congestion. To solve this problem, the Proportional Integral Derivative (PID) controller is introduced into the congestion control mechanism to control the queue length of messages in nodes. By running the PID algorithm on cluster head nodes, the effective collection of sensor data is realized. In addition, a fuzzy control algorithm is proposed to solve the problems of slow parameter optimization, limited adaptive ability and poor optimization precision of traditional PID controller. However, the parameter selection of the fuzzy control algorithm relies too much on expert experience and has certain limitations. Therefore, this manuscript proposes the Cuckoo Fuzzy-PID Controller (CFPID), whose core idea is to apply the cuckoo search algorithm to optimize the fuzzy PID controller's quantization factor and PID parameter increment. Simulation results show that in comparison with the existing methods, the instantaneous queue length and real-time packet loss rate of CFPID are better.

14.
Sensors (Basel) ; 20(14)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708534

RESUMO

The Internet of Things (IoT) is a world of connected networks and modern technology devices, among them vehicular networks considered more challenging due to high speed and network dynamics. Future trends in IoT allow these inter networks to share information. Also, the previous security solutions to vehicular IoT (VIoT) much emphasize on privacy protection and security related issues using public keys infrastructure. However, the primary concern about efficient trust assessment, authorized users malfunctioning, and secure information dissemination in vehicular wireless networks have not been explored. To cope with these challenges, we propose a trust enhanced on-demand routing (TER) scheme, which adopts TrustWalker (TW) algorithm for efficient trust assessment and route search technique in VIoT. TER comprised of novel three-valued subjective logic (3VSL), TW algorithm, and ad hoc on-demand distance vector (AODV) routing protocol. The simulated results validate the accuracy of the proposed scheme in term of throughput, packet drop ratio (PDR), and end to end (E2E) delay. In the simulation, the execution time of the TW algorithm is analyzed and compared with another route search algorithm, i.e., Assess-Trust (AT), by considering real-world online datasets such as Pretty Good Privacy and Advogato. The accuracy and efficiency of the TW algorithm, even with a large number of vehicle users, are also demonstrated through simulations.

15.
Molecules ; 25(16)2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32796509

RESUMO

Berberis laurina (Berberidaceae) is a well-known medicinal plant used in traditional medicine since ancient times; however, it is scarcely studied to a large-scale fingerprint. This work presents a broad-range fingerprints determination through high-resolution magical angle spinning (HR-MAS) nuclear magnetic resonance (NMR) spectroscopy, a well-established flexible analytical method and one of most powerful "omics" platforms. It had been intended to describe a large range of chemical compositions in all plant parts. Beyond that, HR-MAS NMR allowed the direct investigation of botanical material (leaves, stems, and roots) in their natural, unaltered states, preventing molecular changes. The study revealed 17 metabolites, including caffeic acid, and berberine, a remarkable alkaloid from the genus Berberis L. The metabolic pattern changes of the leaves in the course of time were found to be seasonally dependent, probably due to the variability of seasonal and environmental trends. This metabolites overview is of great importance in understanding plant (bio)chemistry and mediating plant survival and is influenceable by interacting environmental means. Moreover, the study will be helpful in medicinal purposes, health sciences, crop evaluations, and genetic and biotechnological research.


Assuntos
Berberis/química , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Metaboloma , Extratos Vegetais/análise , Extratos Vegetais/metabolismo , Plantas Medicinais/química , Folhas de Planta/química
16.
J Nat Prod ; 82(8): 2252-2261, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31343173

RESUMO

Microtubule affinity regulating kinase 4 (MARK4) is a potential drug target for neuronal disorders and several types of cancers. Filtration of naturally occurring compound libraries using high-throughput screening and enzyme assay suggest α-mangostin is a potential inhibitor of MARK4. Structure-based docking and 100 ns molecular dynamics simulation revealed that the binding of α-mangostin stabilizes the MARK4 structure. Enzyme inhibition and binding studies showed that α-mangostin inhibited MARK4 in the submicromolar range with IC50 = 1.47 µM and binding constant (Ka) 5.2 × 107 M-1. Cell-based studies suggested that α-mangostin inhibited the cell viability (MCF-7 and HepG2), induced apoptosis, arrested the cell cycle in the G0/G1 phase, and reduced tau-phosphorylation. This study implicates MARK4 as a new target of α-mangostin, adding an additional lead molecule to the anticancer repertoire.


Assuntos
Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Xantonas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Ligantes , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Espécies Reativas de Oxigênio/metabolismo
17.
Cell Physiol Biochem ; 46(2): 505-519, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29614492

RESUMO

BACKGROUND/AIMS: The major histocompatibility complex (MHC) categorized into three (I, II and III) classes elicits the immunogenic response by presenting exogenous peptides to T cells. The MHC-II DM is composed of DMα and DMß, two polypeptide chains, both are encoded by separate MHC genes involved in antigen processing and presentation. Despite the acknowledged role of MHC complex in humans, the literature is silent on the organization and expression of these genes in water buffalo Bubalus bubalis, an agriculturally important animal species. METHODS: We deduced the full-length mRNA sequences of DMα and DMß genes, localized them onto the chromosome 2, assessed their copy number per haploid genome and studied tissue and disease specific expression. RESULTS: The Real Time PCR showed higher expression of both the genes and their seven interacting partners in spleen, gonads and spermatozoa. Significantly, upregulation of DMα and DMß genes and their interacting partners were detected in diseased group of buffaloes as compared to that in healthy ones. CONCLUSION: The upregulation of Bubalus bubalis (BuLA)-DMα and DMß genes and their interacting partners reflect their role in regulating immune responses towards the amelioration of diseases. Work on this line would enhance our understanding on the overall roles of MHC locus, allowing development of possible therapeutic treatment strategies.


Assuntos
Búfalos/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Animais , Sequência de Bases , Cromossomos/genética , Cromossomos/metabolismo , Clonagem Molecular , Variações do Número de Cópias de DNA , Haploidia , Hemoglobinúria/genética , Hemoglobinúria/patologia , Hemoglobinúria/veterinária , Hérnia Diafragmática/genética , Hérnia Diafragmática/patologia , Hérnia Diafragmática/veterinária , Antígenos de Histocompatibilidade Classe II/genética , Humanos , Hibridização in Situ Fluorescente , Pneumonia/genética , Pneumonia/patologia , Pneumonia/veterinária , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Regulação para Cima
19.
Microb Pathog ; 115: 93-99, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29273508

RESUMO

Shiga toxin Escherichia coli (STEC) O157:H7 is an important zoonotic food borne pathogen causing gastroenteritis that may lead to life threatening hemorragic colitis (HC) and hemorrhagic uremic syndrome (HUS). 325 meat and tissue samples were tested for enumeration of O157:H7 strains using most probable number (MPN)-PCR targeting their specific genes flicH7 and rfbO157 followed by isolation, sereotyping and pathogenicity testing. The overall prevalence of O157:H7 was 41.3% (134/325) along the production and supply chain of pork (PSCP), being higher in supply chain (59%, 118/200) as compared to pig farms (12.8%, 16/125). Along the PSCP, the highest prevalence was found in slaughter houses (86.25%, 69/80) followed by wet- (53.3%, 32/60) and super-markets (28.3%, 17/60). The MPN values ranged from 3 to 1100 MPN/g in overall positive samples, being higher in slaughter houses followed by wet and super markets. Except from intestine and meat samples of slaughter house, the MPN was found higher in summer as compared to winter samples. Eight STEC O157:H7 isolated from meat and liver samples were tested in Balb/C mice for pathogenicity. After development of clinical signs and symptoms, 50-83.3% mortality was produced in the infected mice. Histopathological investigations revealed visible necrosis of intestinal epithelial cells, shedding of cellular debris in the intestine, while in the kidney, necrosis of renal cortical portion of tubular epithelial cells was observed. STEC O157:H7 is prevalent along PSCP around Hubei of China in different proportions being alarmingly higher in supply chain and markets which is a matter of concern for public health.


Assuntos
Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/isolamento & purificação , Escherichia coli O157/patogenicidade , Microbiologia de Alimentos , Toxinas Shiga/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Escherichia coli Shiga Toxigênica/patogenicidade , Matadouros , Animais , Animais Domésticos , Proteínas de Bactérias/genética , China/epidemiologia , DNA Bacteriano , Modelos Animais de Doenças , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Escherichia coli O157/classificação , Escherichia coli O157/genética , Proteínas de Escherichia coli/genética , Feminino , Flagelina/genética , Contaminação de Alimentos/análise , Intestinos/microbiologia , Intestinos/patologia , Fígado/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Técnicas de Diagnóstico Molecular , Mortalidade , Necrose/microbiologia , Necrose/patologia , Reação em Cadeia da Polimerase , Prevalência , Carne Vermelha/microbiologia , Sorotipagem , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/genética , Suínos , Virulência , Fatores de Virulência/genética
20.
J Physiol ; 595(10): 3085-3095, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27753099

RESUMO

Ca2+ release-activated Ca2+ (CRAC) channels play an essential role in the immune system. The pore-forming subunit, Orai1, is an important pharmacological target. Here, we summarize the recent discoveries on the structure-function relationship of Orai1, as well as its interaction with the native channel opener STIM1 and chemical modulator 2-aminoethoxydiphenyl borate (2-APB). We first introduce the critical structural elements of Orai1, which include a Ca2+ accumulating region, ion selectivity filter, hydrophobic centre, basic region, extended transmembrane Orai1 N-terminal (ETON) region, transmembrane (TM) regions 2 and 3, P245 bend, 263 SHK265 hinge linker and L273-L276 hydrophobic patch. We then hypothesize the possible mechanisms by which STIM1 triggers the conformational transitions of TM regions and exquisitely shapes the ion conduction pathway during generation of the CRAC current (Icrac ) with high Ca2+ selectivity. Finally, we propose mechanisms by which 2-APB modulates Icrac . On the STIM1-activated Orai1 channel, a low dose of 2-APB acts directly, dilating its extremely narrow pore diameter from 3.8 to 4.6 Å, increasing its unitary channel conductance, and potentiating the Icrac . Further elucidation of the structure of the opened CRAC channel and a better understanding of structure-function relationship will benefit the future development of novel immune modulators.


Assuntos
Compostos de Boro/farmacologia , Proteínas de Neoplasias/fisiologia , Proteína ORAI1/química , Proteína ORAI1/fisiologia , Molécula 1 de Interação Estromal/fisiologia , Humanos , Ativação do Canal Iônico/efeitos dos fármacos
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