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1.
J Virol ; 95(20): e0116421, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34346767

RESUMO

One approach to improve the utility of adeno-associated virus (AAV)-based gene therapy is to engineer the AAV capsid to (i) overcome poor transport through tissue barriers and (ii) redirect the broadly tropic AAV to disease-relevant cell types. Peptide- or protein-domain insertions into AAV surface loops can achieve both engineering goals by introducing a new interaction surface on the AAV capsid. However, we understand little about the impact of insertions on capsid structure and the extent to which engineered inserts depend on a specific capsid context to function. Here, we examine insert-capsid interactions for the engineered variant AAV9-PHP.B. The 7-amino-acid peptide insert in AAV9-PHP.B facilitates transport across the murine blood-brain barrier via binding to the receptor Ly6a. When transferred to AAV1, the engineered peptide does not bind Ly6a. Comparative structural analysis of AAV1-PHP.B and AAV9-PHP.B revealed that the inserted 7-amino-acid loop is highly flexible and has remarkably little impact on the surrounding capsid conformation. Our work demonstrates that Ly6a binding requires interactions with both the PHP.B peptide and specific residues from the AAV9 HVR VIII region. An AAV1-based vector that incorporates a larger region of AAV9-PHP.B-including the 7-amino-acid loop and adjacent HVR VIII amino acids-can bind to Ly6a and localize to brain tissue. However, unlike AAV9-PHP.B, this AAV1-based vector does not penetrate the blood-brain barrier. Here we discuss the implications for AAV capsid engineering and the transfer of engineered activities between serotypes. IMPORTANCE Targeting AAV vectors to specific cellular receptors is a promising strategy for enhancing expression in target cells or tissues while reducing off-target transgene expression. The AAV9-PHP.B/Ly6a interaction provides a model system with a robust biological readout that can be interrogated to better understand the biology of AAV vectors' interactions with target receptors. In this work, we analyzed the sequence and structural features required to successfully transfer the Ly6a receptor-binding epitope from AAV9-PHP.B to another capsid of clinical interest, AAV1. We found that AAV1- and AAV9-based vectors targeted to the same receptor exhibited different brain-transduction profiles. Our work suggests that, in addition to attachment-receptor binding, the capsid context in which this binding occurs is important for a vector's performance.


Assuntos
Terapia Genética/métodos , Vetores Genéticos/genética , Ligação Proteica/genética , Aminoácidos/genética , Animais , Antígenos Ly/metabolismo , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Capsídeo/metabolismo , Proteínas do Capsídeo/genética , Dependovirus/genética , Dependovirus/metabolismo , Técnicas de Transferência de Genes , Engenharia Genética/métodos , Células HEK293 , Humanos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Peptídeos/genética , Domínios Proteicos/genética , Transdução Genética/métodos , Transgenes/genética
2.
EMBO J ; 36(6): 797-815, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28219928

RESUMO

Mitochondria exert important control over plasma membrane (PM) Orai1 channels mediating store-operated Ca2+ entry (SOCE). Although the sensing of endoplasmic reticulum (ER) Ca2+ stores by STIM proteins and coupling to Orai1 channels is well understood, how mitochondria communicate with Orai1 channels to regulate SOCE activation remains elusive. Here, we reveal that SOCE is accompanied by a rise in cytosolic Na+ that is critical in activating the mitochondrial Na+/Ca2+ exchanger (NCLX) causing enhanced mitochondrial Na+ uptake and Ca2+ efflux. Omission of extracellular Na+ prevents the cytosolic Na+ rise, inhibits NCLX activity, and impairs SOCE and Orai1 channel current. We show further that SOCE activates a mitochondrial redox transient which is dependent on NCLX and is required for preventing Orai1 inactivation through oxidation of a critical cysteine (Cys195) in the third transmembrane helix of Orai1. We show that mitochondrial targeting of catalase is sufficient to rescue redox transients, SOCE, and Orai1 currents in NCLX-deficient cells. Our findings identify a hitherto unknown NCLX-mediated pathway that coordinates Na+ and Ca2+ signals to effect mitochondrial redox control over SOCE.


Assuntos
Cálcio/metabolismo , Mitocôndrias/metabolismo , Proteína ORAI1/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Sódio/metabolismo , Linhagem Celular , Humanos , Proteínas Mitocondriais , Oxirredução
3.
J Virol ; 93(1)2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30333171

RESUMO

Human adenoviruses (HAdVs) are being explored as vectors for gene transfer and vaccination. Human adenovirus type 26 (HAdV26), which belongs to the largest subgroup of adenoviruses, species D, has a short fiber and a so-far-unknown natural tropism. Due to its low seroprevalence, HAdV26 has been considered a promising vector for the development of vaccines. Despite the fact that the in vivo safety and immunogenicity of HAdV26 have been extensively studied, the basic biology of the virus with regard to receptor use, cell attachment, internalization, and intracellular trafficking is poorly understood. In this work, we investigated the roles of the coxsackievirus and adenovirus receptor (CAR), CD46, and αv integrins in HAdV26 infection of human epithelial cell lines. By performing different gain- and loss-of-function studies, we found that αvß3 integrin is required for efficient infection of epithelial cells by HAdV26, while CAR and CD46 did not increase the transduction efficiency of HAdV26. By studying intracellular trafficking of fluorescently labeled HAdV26 in A549 cells and A549-derived cell clones with stably increased expression of αvß3 integrin, we observed that HAdV26 colocalizes with αvß3 integrin and that increased αvß3 integrin enhances internalization of HAdV26. Thus, we conclude that HAdV26 uses αvß3 integrin as a receptor for infecting epithelial cells. These results give us new insight into the HAdV26 infection pathway and will be helpful in further defining HAdV-based vector manufacturing and vaccination strategies.IMPORTANCE Adenovirus-based vectors are used today for gene transfer and vaccination. HAdV26 has emerged as a promising candidate vector for development of vaccines due to its relatively low seroprevalence and its ability to induce potent immune responses against inserted transgenes. However, data regarding the basic biology of the virus, like receptor usage or intracellular trafficking, are limited. In this work, we found that efficient infection of human epithelial cell lines by HAdV26 requires the expression of the αvß3 integrin. By studying intracellular trafficking of fluorescently labeled HAdV26 in a cell clone with stably increased expression of αvß3 integrin, we observed that HAdV26 colocalizes with αvß3 integrin and confirmed that αvß3 integrin expression facilitates efficient HAdV26 internalization. These results will allow further improvement of HAdV26-based vectors for gene transfer and vaccination.


Assuntos
Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/patogenicidade , Células Epiteliais/metabolismo , Integrina alfaVbeta3/metabolismo , Células A549 , Infecções por Adenovirus Humanos/metabolismo , Linhagem Celular , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Células Epiteliais/citologia , Células Epiteliais/virologia , Humanos , Proteína Cofatora de Membrana/metabolismo , Internalização do Vírus
4.
Proc Natl Acad Sci U S A ; 114(26): E5167-E5176, 2017 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-28611221

RESUMO

Key mitochondrial functions such as ATP production, Ca2+ uptake and release, and substrate accumulation depend on the proton electrochemical gradient (ΔµH+) across the inner membrane. Although several drugs can modulate ΔµH+, their effects are hardly reversible, and lack cellular specificity and spatial resolution. Although channelrhodopsins are widely used to modulate the plasma membrane potential of excitable cells, mitochondria have thus far eluded optogenetic control. Here we describe a toolkit of optometabolic constructs based on selective targeting of channelrhodopsins with distinct functional properties to the inner mitochondrial membrane of intact cells. We show that our strategy enables a light-dependent control of the mitochondrial membrane potential (Δψm) and coupled mitochondrial functions such as ATP synthesis by oxidative phosphorylation, Ca2+ dynamics, and respiratory metabolism. By directly modulating Δψm, the mitochondria-targeted opsins were used to control complex physiological processes such as spontaneous beats in cardiac myocytes and glucose-dependent ATP increase in pancreatic ß-cells. Furthermore, our optometabolic tools allow modulation of mitochondrial functions in single cells and defined cell regions.


Assuntos
Sinalização do Cálcio/fisiologia , Channelrhodopsins/metabolismo , Células Secretoras de Insulina/metabolismo , Potencial da Membrana Mitocondrial/fisiologia , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Optogenética , Animais , Células HEK293 , Células HeLa , Humanos , Células Secretoras de Insulina/citologia , Consumo de Oxigênio/fisiologia , Ratos , Ratos Sprague-Dawley
5.
Biochim Biophys Acta Mol Cell Res ; 1864(6): 997-1008, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28130126

RESUMO

BACKGROUND: The Na+/Ca2+/Li+ exchanger (NCLX) is a member of the Na+/Ca2+ exchanger family. NCLX is unique in its capacity to transport both Na+ and Li+, unlike other members, which are Na+ selective. The major aim of this study was twofold, i.e., to identify NCLX residues that confer Li+ or Na+ selective Ca2+ transport and map their putative location on NCLX cation transport site. METHOD: We combined molecular modeling to map transport site of NCLX with euryarchaeal H+/Ca2+ exchanger, CAX_Af, and fluorescence analysis to monitor Li+ versus Na+ dependent mitochondrial Ca2+ efflux of transport site mutants of NCLX in permeabilized cells. RESULT: Mutation of Asn149, Pro152, Asp153, Gly176, Asn467, Ser468, Gly494 and Asn498 partially or strongly abolished mitochondrial Ca2+ exchange activity in intact cells. In permeabilized cells, N149A, P152A, D153A, N467Q, S468T and G494S demonstrated normal Li+/Ca2+ exchange activity but a reduced Na+/Ca2+ exchange activity. On the other hand, D471A showed dramatically reduced Li+/Ca2+ exchange, but Na+/Ca2+ exchange activity was unaffected. Finally, simultaneous mutation of four putative Ca2+ binding residues was required to completely abolish both Na+/Ca2+ and Li+/Ca2+ exchange activities. CONCLUSIONS: We identified distinct Na+ and Li+ selective residues in the NCLX transport site. We propose that functional segregation in Li+ and Na+ sites reflects the functional properties of NCLX required for Ca2+ exchange under the unique membrane potential and ion gradient across the inner mitochondrial membrane. GENERAL SIGNIFICANCE: The results of this study provide functional insights into the unique Li+ and Na+ selectivity of the mitochondrial exchanger. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.


Assuntos
Cálcio/metabolismo , Lítio/metabolismo , Mitocôndrias/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Sódio/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Transporte Biológico , Células HEK293 , Humanos , Proteínas Mitocondriais , Mutação , Homologia de Sequência de Aminoácidos , Trocador de Sódio e Cálcio/química
6.
J Biol Chem ; 292(13): 5364-5377, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28196860

RESUMO

NCLX is a Na+/Ca2+ exchanger that uses energy stored in the transmembrane sodium gradient to facilitate the exchange of sodium ions for ionic calcium. Mammals have a single NCLX, which has been shown to function primarily at the mitochondrion and is an important regulator of neuronal physiology by contributing to neurotransmission and synaptic plasticity. The role of NCLX in developmental cell patterning (e.g. in neural circuits) is largely unknown. Here we describe a novel role for the Caenorhabditis elegans NCLX-type protein, NCX-9, in neural circuit formation. NCX-9 functions in hypodermal seam cells that secrete the axon guidance cue UNC-129/BMP, and our data revealed that ncx-9-/- mutant animals exhibit development defects in stereotyped left/right axon guidance choices within the GABAergic motor neuron circuit. Our data also implicate NCX-9 in a LON-2/heparan sulfate and UNC-6/netrin-mediated, RAC-dependent signaling pathway to guide left/right patterning within this circuit. Finally, we also provide in vitro physiology data supporting the role for NCX-9 in handling calcium exchange at the mitochondrion. Taken together, our work reveals the specificity by which the handling by NCLX of calcium exchange can map to neural circuit patterning and axon guidance decisions during development.


Assuntos
Orientação de Axônios/fisiologia , Padronização Corporal/fisiologia , Caenorhabditis elegans/fisiologia , Trocador de Sódio e Cálcio/fisiologia , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/fisiologia , Cálcio/metabolismo , Mitocôndrias/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/fisiologia
7.
Respiration ; 93(6): 436-440, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28355597

RESUMO

Treatment options for intractable life-threatening haemoptysis in mechanically ventilated patients with structural lung disease who do not respond to bronchial artery embolisation (BAE) and who are deemed unfit for surgery are limited. A 26-year-old HIV-positive male with a poorly preserved CD4 count and active pulmonary tuberculosis was intubated and mechanically ventilated for persistent life-threatening haemoptysis. Two attempts at BAE failed, and life-threatening haemoptysis recurred daily for 14 days despite antituberculous therapy. He was deemed unfit for surgery during that period. We proceeded to identify the source of bleeding endoscopically and implanted an endobronchial valve in the left upper lobe bronchus. Following the collapse of the affected lobe, haemoptysis ceased and the patient was promptly liberated from mechanical ventilation. He remained haemoptysis free for the duration of his hospitalisation. Endobronchial valves, therefore, may be a viable option in patients mechanically ventilated with persistent life-threatening haemoptysis in whom all other conventional measures fail and who are considered unfit for surgery.


Assuntos
Hemoptise/cirurgia , Próteses e Implantes , Terapia de Salvação , Choque Hemorrágico/cirurgia , Adulto , Antituberculosos/uso terapêutico , Broncoscopia , Infecções por HIV/complicações , Hemoptise/complicações , Hemoptise/diagnóstico por imagem , Humanos , Masculino , Radiografia Torácica , Respiração Artificial , Choque Hemorrágico/etiologia , Sucção , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/terapia
8.
J Gen Virol ; 97(9): 2117-2128, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27311834

RESUMO

Recombinant measles virus (rMV) vectors expressing heterologous viral membrane protein antigens are potentially useful as vaccines. Genes encoding the mumps virus haemagglutinin-neuraminidase (MuV-HN), the influenza virus haemagglutinin (Flu-HA) or the respiratory syncytial virus fusion (RSV-F) proteins were inserted into the genome of a live attenuated vaccine strain of measles virus. Additionally, in this case rMV with the MuV-HN or the influenza HA inserts, chimeric constructs were created that harboured the measles virus native haemagglutinin or fusion protein cytoplasmic domains. In all three cases, sucrose-gradient purified preparations of rMV were found to have incorporated the heterologous viral membrane protein on the viral membrane. The possible utility of rMV expressing RSV-F (rMV.RSV-F) as a vaccine was tested in a cotton rat challenge model. Vaccination with rMV.RSV-F efficiently induced neutralizing antibodies against RSV and protected animals from infection with RSV in the lungs.


Assuntos
Portadores de Fármacos , Vetores Genéticos , Vírus do Sarampo/genética , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vírus Sinciciais Respiratórios/imunologia , Proteínas da Matriz Viral/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Modelos Animais de Doenças , Pulmão/imunologia , Pulmão/virologia , Coelhos , Vírus Sinciciais Respiratórios/genética , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Proteínas da Matriz Viral/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
9.
Br J Psychiatry ; 208 Suppl 56: s71-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26447170

RESUMO

BACKGROUND: An essential element of mental health service scale up relates to an assessment of resource requirements and cost implications. AIMS: To assess the expected resource needs of scaling up services in five districts in sub-Saharan Africa and south Asia. METHOD: The resource quantities associated with each site's specified care package were identified and subsequently costed, both at current and target levels of coverage. RESULTS: The cost of the care package at target coverage ranged from US$0.21 to 0.56 per head of population in four of the districts (in the higher-income context of South Africa, it was US$1.86). In all districts, the additional amount needed each year to reach target coverage goals after 10 years was below $0.10 per head of population. CONCLUSIONS: Estimation of resource needs and costs for district-level mental health services provides relevant information concerning the financial feasibility of locally developed plans for successful scale up.


Assuntos
Serviços Comunitários de Saúde Mental/economia , Custos de Cuidados de Saúde , Mão de Obra em Saúde/economia , Transtornos Mentais/terapia , Planejamento de Assistência ao Paciente/economia , Países em Desenvolvimento , Etiópia , Humanos , Índia , Nepal , África do Sul , Uganda
10.
Respiration ; 92(6): 428-431, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27760430

RESUMO

A 66-year-old female from a rural area in South Africa presented with non-life-threatening haemoptysis. Radiologic and serological investigations attributed her symptoms to bilateral, large echinococcal cysts. She declined surgery despite her lung physiologic parameters, which deemed her eligible. Medical therapy with oral albendazole was initiated with excellent clinical and radiologic response during a follow-up period of 18 months. To our knowledge, this is one of the first reported cases in the literature that shows complete resolution of bilateral large echinococcal cysts with medical treatment alone in an adult patient.


Assuntos
Albendazol/uso terapêutico , Anti-Helmínticos/uso terapêutico , Equinococose Pulmonar/tratamento farmacológico , Idoso , Equinococose Pulmonar/diagnóstico por imagem , Feminino , Humanos , Radiografia Torácica , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
J Virol ; 88(15): 8468-78, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24829340

RESUMO

UNLABELLED: The possibility that vaccination with adenovirus (AdV) vectors increased mucosal T cell activation remains a central hypothesis to explain the potential enhancement of HIV acquisition within the Step trial. Modeling this within rhesus macaques is complicated because human adenoviruses, including human adenovirus type 5 (HAdV-5), are not endogenous to macaques. Here, we tested whether vaccination with a rhesus macaque-derived adenoviral vector (simian adenovirus 7 [SAdV-7]) enhances mucosal T cell activation within rhesus macaques. Following intramuscular SAdV-7 vaccination, we observed a pronounced increase in SAdV-7-specific CD4(+) T cell responses in peripheral blood and, more dramatically, in rectal mucosa tissue. Vaccination also induced a significant increase in the frequency of activated memory CD4(+) T cells in SAdV-7- and HAdV-5-vaccinated animals in the rectal mucosa but not in peripheral blood. These fluctuations within the rectal mucosa were also associated with a pronounced decrease in the relative frequency of naive resting CD4(+) T cells. Together, these results indicate that peripheral vaccination with an AdV vector can increase the activation of mucosal CD4(+) T cells, potentially providing an experimental model to further evaluate the role of host-vector interactions in increased HIV acquisition after AdV vector vaccination. IMPORTANCE: The possibility that vaccination with a human adenovirus 5 vector increased mucosal T cell activation remains a central hypothesis to explain the potential enhancement of human immunodeficiency virus (HIV) acquisition within the Step trial. In this study, we tested whether vaccination with a rhesus macaque-derived adenoviral vector in rhesus macaques enhances mucosal CD4(+) T cell activation, the main cell target of simian immunodeficiency virus (SIV)/HIV. The results showed that vaccination with an adenoviral vector indeed increases activation of mucosal CD4(+) T cells and potentially increases susceptibility to SIV infection.


Assuntos
Adenovirus dos Símios/imunologia , Linfócitos T CD4-Positivos/imunologia , Vetores Genéticos/imunologia , Imunidade nas Mucosas , Animais , Sangue/imunologia , Mucosa Intestinal/imunologia , Macaca mulatta , Reto/imunologia , Vacinação/métodos
12.
Mol Cell Biochem ; 385(1-2): 53-68, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24065388

RESUMO

We investigated the mechanism by which TxA2 mimetic, U46619, activates proMMP-2 in bovine pulmonary artery smooth muscle cells. Our study showed that treatment of the cells with U46619 caused an increase in the expression and subsequently activation of proMMP-2 in the cells. Pretreatment with p(38)MAPK inhibitor, SB203580; and NF-κB inhibitor, Bay11-7082 inhibited the expression and activation of proMMP-2 induced by U46619. U46619 also induced increase in MT1-MMP expression, which was inhibited upon pretreatment with SB203580 and Bay11-7082. U46619 treatment to the cells stimulated p(38)MAPK activity as well as NF-κB activation by IκB-α phosphorylation, translocation of NF-κBp65 subunit from cytosol to nucleus and subsequently, by increasing its DNA-binding activity. Induction of NF-κB activation seems to be mediated through IKK, as transfection of cells with either IKKα or IKKß siRNA prevented U46619-induced phosphorylation of IκB-α and NF-κBp65 DNA-binding activity. U46619 treatment to the cells also downregulated the TIMP-2 level. Pretreatment of the cells with SB203580 and Bay11-7082 did not show any discernible change in TIMP-2 level by U46619. Overall, U46619-induced activation of proMMP-2 is mediated via involvement of p(38)MAPK-NFκB-MT1MMP signaling pathway with concomitant downregulation of TIMP-2 expression in bovine pulmonary artery smooth muscle cells.


Assuntos
Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Precursores Enzimáticos/metabolismo , Gelatinases/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Miócitos de Músculo Liso/enzimologia , NF-kappa B/metabolismo , Artéria Pulmonar/citologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Bovinos , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Proteínas I-kappa B/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Inibidor de NF-kappaB alfa , Fosforilação/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Regulação para Cima/efeitos dos fármacos
13.
Mol Cell Biochem ; 393(1-2): 309-17, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24850186

RESUMO

We have identified a novel endogenous low mol wt. (15.6 kDa) protein inhibitor of Na(+)/K(+)-ATPase in cytosolic fraction of bovine pulmonary artery smooth muscle cells. The inhibitor showed different affinities toward the α2ß1 and α1ß1 isozymes of Na(+)/K(+)-ATPase, where α2 is more sensitive than α1. The inhibitor interacted reversibly to the E1 site of the enzyme and blocked the phosphorylated intermediate formation. Circular dichroism study suggests that the inhibitor causes an alteration in the confirmation of the enzyme.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Animais , Bovinos , Dicroísmo Circular , Citosol/enzimologia , Peso Molecular , Miócitos de Músculo Liso/enzimologia , Artéria Pulmonar/enzimologia , ATPase Trocadora de Sódio-Potássio/química
14.
Arch Biochem Biophys ; 540(1-2): 133-44, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24184446

RESUMO

Treatment of bovine pulmonary artery smooth muscle cells (BPASMCs) with U46619 attenuated isoproterenol caused stimulation of adenyl cyclase activity and cAMP production. Pretreatment with SQ29548 (Tp receptor antagonist), apocynin (NADPH oxidase inhibitor) and Go6976 (PKC-α inhibitor) eliminated U46619 caused attenuation of isoproterenol stimulated adenyl cyclase activity. Pretreatment with SQ29548 and apocynin prevented U46619 induced increase in NADPH oxidase activity, PKC-α activity and Giα phosphorylation. However, pretreatment with CZI, a PKC-ζ inhibitor, markedly, but not completely, inhibited U46619 induced increase in NADPH oxidase activity, PKC-α activity, Giα phosphorylation and also significantly eliminated U46619 caused attenuation of isoproterenol stimulated adenyl cyclase activity. Pretreatment with Go6976 inhibited U46619 induced increase in Giα phosphorylation, but not PKC-ζ activity and NADPH oxidase activity. Pretreatment with pertussis toxin eliminated U46619 caused attenuation of isoproterenol stimulated adenyl cyclase activity without any discernible change in PKC-ζ, NADPH oxidase and PKC-α activities. Transfection of the cells with Tp, PKC-ζ and PKC-α siRNA duplexes corroborate the findings observed with their respective pharmacological inhibitors on the responses produced by U46619. Taken together, we suggest involvement of PKC-ζ in U46619 caused attenuation of isoproterenol stimulated ß-adrenergic response, which is regulated by NADPH oxidase-PKCα-Giα axis in pulmonary artery smooth muscle cells.


Assuntos
Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , NADPH Oxidases/metabolismo , Proteína Quinase C-alfa/metabolismo , Proteína Quinase C/metabolismo , Receptores Adrenérgicos beta/metabolismo , Adenilil Ciclases/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Animais , Bovinos , AMP Cíclico/biossíntese , Inibidores Enzimáticos/farmacologia , Isoenzimas/metabolismo , Isoproterenol/farmacologia , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/metabolismo , NADPH Oxidases/antagonistas & inibidores , Artéria Pulmonar/citologia
15.
Cureus ; 15(6): e39893, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37404390

RESUMO

INTRODUCTION: Deliberate self-poisoning (DSP) is an important cause of hospital admissions and subsequent mortality. We conducted a cross-sectional observational study in a tertiary-level teaching hospital situated in the northeastern part of Bangladesh to analyze the psychosocial factors responsible for DSP. METHODS: This cross-sectional observational study was carried out among patients with DSP admitted to the medicine ward from January to December 2017, irrespective of gender, except for cases involving poisoning due to spoiled food, food contaminated by infectious organisms, poisoning by venomous animals, and street poisoning (commuter or travel-related poisoning). Consultant psychiatrist in accordance with the Diagnostic & Statistical Manual of Mental Disorder - IV (DSM-IV) confirmed psychiatric disorders. Data were analyzed by SPSS (Statistical Package for social sciences) version 16.0 (IBM Corp., Armonk, NY). RESULTS: Total 100 patients were enrolled. Among them, 43% were male and 57% were female. The majority (85%) of the patients were young, aged below 30 years. The mean age of male patients was 26.2 years and that of females was 21.69 years. Most of the DSP patients were from the lower economic class (59%). The population sample was remarkable for students (Prevalence 37%). The highest percentage of patients (33%) had their educational status at the secondary level. The common reasons for DSP were a family problem in 31% patients, quarrel with boy/girlfriend in 20%, quarrel with a spouse in 13%, quarrel with parents or other family member in 7%, failure in examination in 6%, poverty in 3%, and unemployment in 3%. Prescription medication was the most common poison material (38%), followed by insecticides (36%), household cleaners (17%), and rodenticides (8%). Seven (7%) patients reported previous deliberate self-harm events and co-morbid psychiatric disorder was present in 30% patients among them major depressive disorder was found in 60%, and schizophrenia in 23.3% cases. CONCLUSION: DSP remains a problem mainly for the young with gender ratio-favoring females. The majority of DSPs were educated up to secondary level, unmarried, residents of rural areas, student, and belonged to the lower class. Familial disharmony and quarrel with spouse or friends were the common reason behind DSP. Prescription medication and insecticides were commonly used for DSP. Psychiatric disorders, primarily depressive disorder, and schizophrenia were common in cases of DSP.

16.
Toxicol Rep ; 11: 350-354, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37868809

RESUMO

Background: Paraquat poisoning is one of the leading causes of fatal poisoning in many parts of the world, especially in agricultural countries. Its high toxicity even in small amounts causes rapid damage to multiple organs, especially the kidneys, lungs, and liver, mainly through free radical-mediated injury. As no specific antidote is yet available, early diagnosis and the importance of supportive therapy are critical parts of management. Some evidence suggests a survival benefit from using immunosuppressive drugs. Case report: This case presentation concerns a 15-year-old boy from a village with a history of herbicide poisoning, later confirmed to be paraquat. Despite supportive therapy her condition continued to deteriorate with features of kidney and lung damage. The patient was then treated with methylprednisolone 500 mg daily for 5 days, along with other supportive care, and has made a remarkable recovery. Conclusions: High efficacy as an herbicide, availability and low cost make paraquat an easy-to-encounter poison for suicidal or accidental use. Its high fatality calls for urgent and effective strategies to save lives. Methylprednisolone may play a role in its treatment.

17.
Emerg Infect Dis ; 18(7): 1081-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22709783

RESUMO

Adenoviruses can cause infectious diarrheal disease or respiratory infections in humans; 2 recent reports have indicated probable human infection with simian adenoviruses (SAdVs). To assess the possibility of animal-to-human transmission of SAdVs, we tested fecal samples from asymptomatic rhesus macaques housed in 5 primate facilities in the United States and cultured 23 SAdV isolates. Of these, 9 were purified and completely sequenced; 3 SAdV samples from the American Type Culture Collection (SAdV-6, SAdV-18, and SAdV-20) were also completely sequenced. The sequence of SAdV-18 was closely related to that of human adenovirus F across the whole genome, and the new isolates were found to harbor 2 fiber genes similar to those of human adenovirus (HAdV) strains HAdV-40 and HAdV-41, which can cause infectious diarrhea. The high prevalence of adenoviruses in fecal samples from asymptomatic rhesus macaques and the similarity of the isolates to human strains indicates the possibility of animal-to-human transmission of SAdVs.


Assuntos
Infecções por Adenoviridae/veterinária , Adenovirus dos Símios/isolamento & purificação , Fezes/virologia , Macaca mulatta/virologia , Doenças dos Macacos/transmissão , Zoonoses/transmissão , Infecções por Adenoviridae/epidemiologia , Infecções por Adenoviridae/transmissão , Infecções por Adenoviridae/virologia , Adenovirus dos Símios/classificação , Adenovirus dos Símios/genética , Sequência de Aminoácidos , Animais , DNA Viral/genética , DNA Viral/isolamento & purificação , Humanos , Dados de Sequência Molecular , Doenças dos Macacos/epidemiologia , Doenças dos Macacos/virologia , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA , Estados Unidos/epidemiologia , Zoonoses/epidemiologia , Zoonoses/virologia
18.
Arch Biochem Biophys ; 523(2): 169-80, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22568895

RESUMO

We have recently reported that treatment of bovine pulmonary artery smooth muscle cells with the thromboxane A(2) mimetic, U46619 stimulated NADPH oxidase derived O(2)(·-) level, which subsequently caused marked increase in [Ca(2+)](i)[17]. Herein, we demonstrated that O(2)(·-)-mediated increase in [Ca(2+)](i) stimulates an aprotinin sensitive proteinase activity, which proteolytically activates PKC-α under U46619 treatment to the cells. The activated PKC-α then phosphorylates p(38)MAPK and that subsequently caused G(i)α phosphorylation leading to stimulation of cPLA(2) activity in the cell membrane.


Assuntos
Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/enzimologia , NADPH Oxidases/metabolismo , Fosfolipases A2 Citosólicas/metabolismo , Artéria Pulmonar/citologia , Superóxidos/metabolismo , Animais , Materiais Biomiméticos/farmacologia , Cálcio/metabolismo , Bovinos , Membrana Celular/efeitos dos fármacos , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Ativação Enzimática/efeitos dos fármacos , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Proteína Quinase C-alfa/genética , Proteína Quinase C-alfa/metabolismo , Tromboxano A2/metabolismo , Vasoconstritores/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
19.
J Neuroimmunol ; 368: 577883, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561428

RESUMO

INTRODUCTION: Large-scale vaccination is considered one of the most effective strategies to control the pandemic of COVID-19. Since its start, different complications have been described thought to be related to vaccination. Here, we present a rare case where encephalopathy, myocarditis, and thrombocytopenia developed simultaneously following the second dose of Pfizer-BioNTech mRNA vaccine (BNT162b2). CASE PRESENTATION: A 15-years-old female presented with fever, altered consciousness, and convulsions after taking the second shot of the vaccine. Clinical and laboratory workup was notable for the presence of thrombocytopenia and myocarditis. No alternative causes of encephalitis were found. The patient responded significantly to methylprednisolone suggesting underlying immune pathogenesis responsible for the clinical features. The diagnostic criteria for possible autoimmune encephalitis were also fulfilled. CONCLUSION: Although rare, the clinician should be aware of the possible adverse events following COVID-19 vaccination. Further research with large pooled data is needed to get more insight into its pathogenesis and causal relationship.


Assuntos
Encefalopatias , COVID-19 , Encefalite , Miocardite , Trombocitopenia , Adolescente , Vacina BNT162 , Vacinas contra COVID-19/efeitos adversos , Encefalite/complicações , Feminino , Humanos , Metilprednisolona/uso terapêutico , Miocardite/diagnóstico , Miocardite/etiologia , Trombocitopenia/induzido quimicamente , Vacinas Sintéticas , Vacinas de mRNA
20.
J Gen Virol ; 92(Pt 8): 1749-1753, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21562118

RESUMO

The complete nucleotide sequence of an isolate of simian adenovirus 7 (SAdV-7) was determined. The genome organization of this isolate was found to be similar to that of other primate adenoviruses with two principal notable points: severe truncation of the E1A and E1B 19K proteins and an E3 region encoding only the 12.5K homologue. The viral gene products of SAdV-7 are most closely related to simian adenovirus 1 (SAdV-1), and like SAdV-1, are related to the human adenovirus species HAdV-F, such as the enteric adenoviruses HAdV-40 and HAdV-41 and the recently defined HAdV-G (HAdV-52). Two kinds of gene transfer vectors were made: a replication-competent SAdV-7-based vector with no genomic deletion, and a standard replication-incompetent vector deleted for E1. Importantly, the E1-deleted vector could be propagated to high titre by trans-complementation in human HEK 293 cells.


Assuntos
Adenovirus dos Símios/genética , Técnicas de Transferência de Genes/instrumentação , Vetores Genéticos/genética , Adenovirus dos Símios/fisiologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Vetores Genéticos/fisiologia , Humanos , Dados de Sequência Molecular , Replicação Viral
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