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1.
Microbiol Spectr ; : e0119323, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37750697

RESUMO

Avipoxviruses are considered as significant viral pathogen infecting a wide range of domestic and wild bird species globally, yet the majority of avipoxviruses that infect the wild bird species remain uncharacterized and their genetic diversities remain unclear. In this study, we present a novel pathogenic avipoxvirus isolated from the cutaneous pox lesions of a wild oriental turtle dove (Streptopelia orientalis), tentatively named as turtle dovepox virus (TDPV). The avipoxvirus was isolated by using the chorioallantoic membranes of specific pathogen-free chicken embryos which showed characteristic focal pock lesions, followed by cytopathic effects in host cells infected with oriental turtle dovepox virus. An effort in sequencing the whole genome of the poxvirus using next-generation sequencing was given, and the first whole genome sequence of TDPV was obtained. The TDPV genome was 281,386 bp in length and contained 380 predicted open reading frames (ORFs). While 336 of the predicted ORFs showed homology to other characterized avipoxviruses, the other 44 ORFs were unique. Subsequent phylogenetic analyses showed that the novel TDPV shared the closest genetic evolutionary linkage with the avipoxviruses isolated from pigeon in South Africa and India, of which the TDPV genome had the highest sequence similarity (92.5%) with South African pigeonpox virus (FeP2). In conclusion, the sequenced TDPV is significantly different from any other avipoxviruses isolated from avian or other natural host species considering genomic architecture and observed sequence similarity index. Thus, it likely should be considered a separate species. IMPORTANCE Over the past few decades, avipoxviruses have been found in a number of wild bird species including the oriental turtle dove. However, there is no whole genome sequence information on avipoxviruses isolated from oriental turtle dove, leaving us unclear about the evolutionary linkage of avipoxviruses in oriental turtle dove and other wild bird species. Thus, we believe that our study makes a significant contribution because it is the first report of the whole genome sequence of TDPV isolated from a wild oriental turtle dove, which enriches the genomic information of the genus Avipoxvirus, furthermore, contributes to tracking the genetic evolution of avipoxviruses-infected oriental turtle dove species.

2.
Front Pharmacol ; 14: 1225256, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601067

RESUMO

Introduction: The oil palm kernel (OPK) expeller is the main byproduct of palm oil, but its utilization is limited. Methods: To obtain angiotensin-I-converting enzyme (ACE) inhibition peptides with Zn-chelating capacity, defatted oil palm kernel globulin hydrolysates (DOPKGH) were subjected to Sephadex G-15 gel electrophoresis, reverse-phase high liquid performance chromatography, and UPLC-ESI-MS/MS analysis. Results and discussion: Five representative oligopeptides, including Gln-Arg-Leu-Asp-Arg-Cys-Lys (QRLERCK), Leu-Leu-Leu-Gly-Val-Ala-Asn-Tyr-Arg (LLLGVANYR), Arg-Ala-Asp-Val-Phe-Asn-Pro-Arg (RADVFNPR), Arg-Val-Ile-Lys-Tyr-Asn-Gly-Gly-Gly-Ser-Gly (RVIKYNGGGSG), and Glu-Val-Pro-Gln-Ala-Tyr-Ile-Pro (EVPQAYIP), without potential toxicity and allergenicity, were identified in DOPKGH. Of these, only EVPQAYIP showed both ACE-inhibitory activity (IC50: 102.75 µmol/L) and Zn-chelating capacity (11.69 mg/g). Molecular docking and inhibition kinetics showed that EVPQAYIP was a competitive inhibitor of ACE because it could bind to Glu384, Lys511, and Gln281 (belonging to the central S1 and S2 pockets, respectively) of ACE. Moreover, EVPQAYIP affects zinc tetrahedral coordination in ACE by binding to Glu411; the amino and carboxyl groups of EVPQAYIP chelate with zinc ions. During gastrointestinal digestion, the ACE inhibitory activity of EVPQAYIP was relatively stable. Additionally, EVPQAYIP enhanced zinc stability in the intestine and exerted antihypertensive effects in spontaneous hypertensive rats. These results suggest the potential application of OPK peptides as ingredients in antihypertensive agents or zinc fortification.

3.
Res Vet Sci ; 132: 439-447, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32777540

RESUMO

T-2 toxin is the most toxic as a type A trichothecenes, which could contaminate grains, especially in wheat and corn. It can cause immune suppression, neurotoxicity, the apoptosis of cells and even induce tumorigenesis. Recent studies have indicated that selenium (Se) have protective effect against mycotoxins-induced toxicity. The present studies was designed to investigate the protective role of Selenomethionine (SeMet) on T-2 toxin-induced toxicity in rabbit's jejunum. 50 New Zealand rabbits were divided into five group (Control group, T-2 group, low-dose Se + T-2 group, medium-dose + T-2 group and high-dose Se + T-2 group). New Zealand rabbits were orally administered with SeMet (0.2, 0.4 and 0.6 mg/kg, Adding diet) for 21 days. On 17th days, each group began to take 0.4 mg/kg of T-2 toxin orally every day for 5 days. We found that rabbit exposed to T-2 toxin could increase the levels of ROS, and decrease activities of antioxidant enzymes and the expression of Occludin and ZO-1. In addition, T-2 toxin could trigger jejunal inflammatory response and enhance the expression of IL-1ß, IL-6 and TNF-α. After SeMet pretreatment, our results indicated that Se attenuated the T-2 toxin-induced oxidative stress, decreasing the level of ROS, MDA and enhancing the activity of SOD and GSH-Px. Moreover, SeMet can alleviate jejunal inflammatory response, and protect the integrity of the intestinal barrier through up-regulating the expression of ZO-1 and Occludin. In the present research, supplementation of 0.2 mg/kg SeMet in the diet could effectively alleviate the T-2 toxin poisoning in rabbits.


Assuntos
Jejuno/patologia , Substâncias Protetoras/farmacologia , Selenometionina/farmacologia , Toxina T-2/toxicidade , Ração Animal/análise , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Jejuno/efeitos dos fármacos , Masculino , Substâncias Protetoras/administração & dosagem , Coelhos , Distribuição Aleatória , Selenometionina/administração & dosagem
4.
Virol Sin ; 33(6): 502-514, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30569292

RESUMO

The development of a vaccine based on human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) that elicits potent protective antibodies against infection has been challenging. Recently, we compared the antibody production patterns of HIV-1 Env gp120 and hepatitis B virus surface antigen (HBsAg) to provide insights into how we may improve the protective efficacy of Env-based immunogens. Our previous study showed that HIV Env and HBsAg display different mechanisms of antibody elicitation and that T cells facilitate the responses to repeated immunizations. Here, to elucidate the detailed roles of primary immunization in immune memory response formation and antibody production, we immunized C57BL/6 mice with each antigen and evaluated the development of T follicular helper (Tfh) cells, germinal centers, and the memory responses involved in prime and boost immunizations. We found that after prime immunization, compared with HBsAg, gp120 induced higher frequencies of Tfh cells and programmed death (PD)-1+ T cells, greater major histocompatibility complex II expression on B cells, comparable activated B cells, but weaker germinal center (GC) reactions and memory B cell responses in the draining lymph nodes, accompanied by slower antibody recall responses and poor immune memory responses. The above results suggested that more PD-1+ T cells arising in primary immunization may serve as major contributors to the slow antibody recall response elicited by HIV-1 Env.


Assuntos
Anticorpos Antivirais/sangue , Proteína gp120 do Envelope de HIV/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Imunoglobulina G/sangue , Memória Imunológica , Animais , Formação de Anticorpos , Linfócitos B/imunologia , Feminino , Centro Germinativo/imunologia , Proteína gp120 do Envelope de HIV/administração & dosagem , Antígenos de Superfície da Hepatite B/administração & dosagem , Imunização , Imunização Secundária , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/imunologia , Células Th1/imunologia
5.
Medicine (Baltimore) ; 96(11): e6322, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28296750

RESUMO

BACKGROUND: The aim of the study was to compare the clinical outcomes of patients undergoing all-arthroscopic (AA) or mini-open (MO) rotator cuff repair. METHODS: The present study evaluated 50 patients who had undergone AA repair and 50 patients who had undergone MO repair with a minimum 1-year follow-up. Every patient was asked to complete the Disabilities of the Arm, Shoulder and Hand (DASH) and visual analog scale (VAS) questionnaires. Constant-Murley score (CMS) and active ranges, forward flexion and external rotation, were also evaluated and documented. One year after surgery, ultrasound evaluation was done to determine the integrity of the rotator cuff for each patient. RESULTS: The average age of enrolled patients at the time of surgery was 53.0 years (range, 40-59 years), and average follow-up was 16.6 months (range, 12-24 months). At 2 weeks, the range of forward flexion in the AA group was larger than that in the MO group (136.5 ±â€Š10.2 vs 132.5 ±â€Š7.7, P = 0.03). On postoperative day 1, the VAS in the MO group was significantly higher than that in the AA group (6.5 ±â€Š0.6 vs 6.1 ±â€Š0.6, P < 0.01). At 1 month, the difference in VAS between both groups reappeared (2.9 ±â€Š0.6 vs 2.6 ±â€Š0.6, P = 0.03). At 1 month, the CMS score of patients in the AA group was higher than that in the MO group (52.8 ±â€Š3.6 vs 50.9 ±â€Š5.0, P = 0.03). At 3 and 6 months, the DASH score of patients in the AA group was lower than that in the MO group (43.8 ±â€Š8.2 vs 47.8 ±â€Š4.4, P < 0.01 and 38.6 ±â€Š4.3 vs 42.7 ±â€Š9.9, P < 0.01, respectively). Mean operative time was longer in the AA group compared with that in the MO group (71.9 ±â€Š17.6 vs 64.7 ±â€Š12.7 minutes, P < 0.01). Five patients (10.0%) in the AA group and 4 patients (8.2%) in the MO group had rotator cuff retear, and 6 patients (12.0%) in the AA group and 8 patients (16.3%) in the MO group had adhesive capsulitis by the end of follow-up. There is no significant difference between the 2 groups in the incidence of complications. We also found that joint exercising at least 3 times per week was associated with better short- and long-term joint function recovery. CONCLUSIONS: The AA approach was associated with less pain and lower DASH score as well as higher CMS score in the early recovery period. No difference was found between the 2 groups in primary and secondary outcomes in the long term, or incidence of complications such as adhesive capsulitis and rotator cuff retear. In conclusion, we consider that the AA procedure has better recovery at short-term follow-ups, while both techniques are equivalent regarding long-term outcomes.


Assuntos
Artroscopia/métodos , Procedimentos Ortopédicos/métodos , Lesões do Manguito Rotador/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Manejo da Dor/métodos , Complicações Pós-Operatórias/epidemiologia , Amplitude de Movimento Articular , Recuperação de Função Fisiológica
6.
Vaccine ; 34(50): 6276-6284, 2016 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-27843002

RESUMO

To date, we still lack an ideal strategy for designing envelope glycoprotein (Env) vaccines to elicit potent protective antibodies against HIV-1 infection. Since the human hepatitis B virus surface antigen (HBsAg) is representative of effective vaccines that can induce ideal humoral immune responses, knowledge of how it elicits antibody responses and T helper cells would be an useful reference for HIV vaccine development. We compared the characteristics of the HIV-1 Env gp120 trimer and HBsAg in antibody elicitation and induction of T follicular helper (Tfh) and memory B cells in immunized Balb/c mice. Using the strategy of protein prime-protein boost, we found that HIV-1 gp120 induced slower recall antibody responses but redundant non-specific IgG responses at early time after boosting compared to HBsAg. The higher frequency of PD-1hiCD4+ T cells and Tfh cells that appeared at the early time point after gp120 boosting is likely to limit the development of memory B cells, memory T cells, and specific antibody recall responses. These findings regarding the different features of HIV envelope and HBsAg in T helper cell responses may provide a direction to improve HIV envelope immunogenicity.


Assuntos
Anticorpos Antivirais/sangue , Formação de Anticorpos , Proteína gp120 do Envelope de HIV/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Animais , Linfócitos B/imunologia , Feminino , Camundongos Endogâmicos BALB C , Linfócitos T/imunologia
7.
PLoS One ; 9(12): e115047, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25546013

RESUMO

The CD4 binding site (CD4BS) of the HIV-1 envelope glycoprotein (Env) contains epitopes for broadly neutralizing antibody (nAb) and is the target for the vaccine development. However, the CD4BS core including residues 425-430 overlaps the B cell superantigen site and may be related to B cell exhaustion in HIV-1 infection. Furthermore, production of nAb and high-affinity plasma cells needs germinal center reaction and the help of T follicular helper (Tfh) cells. We believe that strengthening the ability of Env CD4BS in inducing Tfh response and decreasing the effects of the superantigen are the strategies for eliciting nAb and development of HIV-1 vaccine. We constructed a gp120 mutant W427S of an HIV-1 primary R5 strain and examined its ability in the elicitation of Ab and the production of Tfh by immunization of BALB/c mice. We found that the trimeric wild-type gp120 can induce more non-specific antibody-secreting plasma cells, higher serum IgG secretion, and more Tfh cells by splenocyte. The modified W427S gp120 elicits higher levels of specific binding antibodies as well as nAbs though it produces less Tfh cells. Furthermore, higher Tfh cell frequency does not correlate to the specific binding Abs or nAbs indicating that the wild-type gp120 induced some non-specific Tfh that did not contribute to the production of specific Abs. This gp120 mutant led to more memory Tfh production, especially, the effector memory Tfh cells. Taken together, W427S gp120 could induce higher level of specific binding and neutralizing Ab production that may be associated with the reduction of non-specific Tfh but strengthening of the memory Tfh.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/genética , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Mutação , Linfócitos T Auxiliares-Indutores/imunologia , Vacinas contra a AIDS/imunologia , Animais , Especificidade de Anticorpos , Sítios de Ligação , Antígenos CD4/metabolismo , Feminino , Anticorpos Anti-HIV/sangue , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1/genética , Memória Imunológica , Camundongos , Camundongos Endogâmicos BALB C
8.
J Acquir Immune Defic Syndr ; 67(5): 472-80, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25202919

RESUMO

OBJECTIVE: Knowledge about the profile of neutralization responses and the viral envelope features of HIV-1-infected individuals in China may provide new insights for vaccine design against local viruses. METHODS: Eight hundred sixty plasma samples from antiretroviral treatment-naive HIV-1-infected individuals in Xinjiang province (611) and Guangxi province (249), who had acquired infection over 3 years through intravenous drug use or sexual contact, were examined for their ability to neutralize diverse envelope-pseudoviruses of 5 subtypes. The sequence features of the envelopes from elite neutralizers were analyzed. RESULTS: From Xinjiang and Guangxi, 29.1% and 5.2% of plasmas displayed intrasubtype cross neutralization against subtype B and subtype C, respectively. From Xinjiang, 10.6% of the plasmas displayed broad neutralization against the 3 subtypes, B, C, and CRF01_AE; whereas only 2.4% from Guangxi displayed broad neutralization. Envelopes from 6 elite neutralizers were obtained by single-genome amplification. The variations of their envelopes including the lengths, glycans, and net charges in V1, V2, and V4 regions were compared with those from CRF07_BC env sequences from the HIV Sequence Database. The Envs from 3 elite neutralizers displayed the sensitivities to the monoclonal broadly neutralizing antibodies such as PG9, PG16, and 4E10. Some unique characteristics of the envelope glycoproteins from the Chinese elite neutralizers were found. CONCLUSIONS: The neutralization profile of HIV-1-infected individuals in the 2 regions of China, where the HIV-1 subtypes are the representative in China, and the unique characteristics of the envelope glycoproteins from the Chinese elite neutralizers provide useful information for viral infection prevention and an insight for vaccine design against locally epidemic viruses.


Assuntos
Anticorpos Neutralizantes/sangue , Reações Cruzadas , Anticorpos Anti-HIV/sangue , Infecções por HIV/imunologia , HIV-1/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , China , Humanos
9.
Appl Microbiol Biotechnol ; 91(3): 731-40, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21556920

RESUMO

Ideal immunogenicity in antigens is a prerequisite to eliciting a sufficiently strong immune and memory response via either DNA or protein vaccines. To improve immunogenicity, efforts have focused on high-level expression of target proteins and on maintaining their natural conformations. In the present work, two trimer motifs (MTQ and MTI) were designed and introduced into a plasmid vector with the tissue plasminogen activator signal peptide (tPA-SP). Next, we examined the efficacy and the efficiency of the two motifs as well as the introduction of tPA-SP and its mutant forms, 22P/A and 22P/G, in facilitating the secretory expression of trimeric proteins in mammalian cells. We found that both trimer motifs could produce the target protein in a trimeric form at a high level. Introduction of tPA-SP 22P/A markedly increased the secretory expression level. The combination of the trimer motif, MTQ, and the signal peptide, 22P/A, may serve as a universal mammalian vector for producing trimeric proteins in vaccine development.


Assuntos
Motivos de Aminoácidos/imunologia , Complexos Multiproteicos , Sinais Direcionadores de Proteínas/genética , Ativador de Plasminogênio Tecidual/genética , Sequência de Aminoácidos , Ensaio de Imunoadsorção Enzimática , Células HEK293 , HIV/genética , HIV/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/metabolismo , Mutação , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Ativador de Plasminogênio Tecidual/imunologia , Vacinas de DNA/imunologia , Vacinas de Subunidades Antigênicas/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo
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