Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Zhonghua Wei Chang Wai Ke Za Zhi ; 27(3): 247-260, 2024 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-38532587

RESUMO

Objective: To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications. Methods: This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression. Results: The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion: Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.


Assuntos
Neoplasias Colorretais , Neoplasias Gástricas , Feminino , Humanos , Estudos de Coortes , Neoplasias Colorretais/cirurgia , Gastrectomia/métodos , Incidência , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Neoplasias Gástricas/cirurgia , Masculino
2.
Hernia ; 28(2): 517-526, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38180626

RESUMO

PURPOSE: Frailty has shown promise in predicting postoperative morbidity and mortality following hernia surgery. This study aims to evaluate the predictive capacity of the 11-item modified frailty index (mFI) in estimating postoperative outcomes following elective hernia surgery using the National Inpatient Sample (NIS) database. METHODS: A retrospective analysis of the NIS from 2015 to 2019 was performed including adult patients who underwent elective hernia repair. The mFI was used to stratify patients as either frail (mFI ≥ 0.27) or robust (mFI < 0.27). The primary outcomes were in-hospital postoperative morbidity and mortality. The secondary outcomes were system-specific morbidity, length of stay (LOS), total in-hospital healthcare cost, and discharge disposition. Univariable and multivariable regressions were utilized. RESULTS: In total, 14,125 robust patients and 1704 frail patients were included. Frailty was associated with an increased age (mean age 66.4 years vs. 52.6 years, p < 0.001) and prevalence of ventral hernias (51.9% vs. 44.4%, p < 0.001). Adjusted analyses demonstrated that frail patients had increased in-hospital mortality (adjusted odds ratio (aOR) 3.89, 95% CI 1.50, 10.11, p = 0.005), postoperative overall morbidity (aOR 1.98, 95% CI 1.72, 2.29, p < 0.001), postoperative LOS (adjusted mean difference (aMD) 0.78 days, 95% CI 0.51, 1.06, p < 0.001), total in-hospital healthcare costs (aMD $7562 95% CI 3292, 11,832, p = 0.001), and were less likely to be discharged home (aOR 0.61, 95% CI 0.53, 0.69, p < 0.001). CONCLUSION: The mFI may be a reliable predictor of postoperative morbidity and mortality in elective hernia surgery. Utilizing this tool can aid in patient education and identifying high-risk patients who may benefit from tailored prehabilitation.


Assuntos
Fragilidade , Adulto , Humanos , Idoso , Fragilidade/complicações , Fragilidade/epidemiologia , Herniorrafia/efeitos adversos , Fatores de Risco , Pacientes Internados , Estudos Retrospectivos , Morbidade , Hérnia/complicações , Complicações Pós-Operatórias/epidemiologia , Medição de Risco
3.
Front Surg ; 10: 1251444, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37818209

RESUMO

Background: Surgical site infections (SSI) complicate up to 40% of surgical procedures, leading to increased patient morbidity and mortality. Previous research identified disparities in SSI prevention guidelines and clinical practices across different institutions. The study aims to identify variations in SSI prevention practices within and between specialties and financial systems and provide a representation of existing SSI preventative measures to help improve the standardization of SSI prevention practices. Methods: This collaborative cross-sectional survey will be aimed at pan-surgical specialties internationally. The study has been designed and will be reported in line with the CROSS and CHERRIES standards. An international study steering committee will design and internally validate the survey in multiple consensus-based rounds. This will be based on SSI prevention measures outlined in the CDC (2017), WHO (2018), NICE (2019), Wounds UK (2020) and the International Surgical Wound Complications Advisory Panel (ISWCAP) guidelines. The questionnaire will include demographics, SSI surveillance, preoperative, peri-operative and postoperative SSI prevention. Data will be collected on participants' surgical specialty, operative grade, of practice and financial healthcare system of practice. The online survey will be designed and disseminated using QualtricsXM Platform™ through national and international surgical colleges and societies, in addition to social media and snowballing. Data collection will be open for 3 months with reminders, and raking will be used to ascertain the sample. Responses will be analyzed, and the chi-square test used to evaluate the impact of SSI prevention variables on responses. Discussion: Current SSI prevention practice in UK Vascular surgery varies considerably, with little consensus on many measures. Given the inconsistency in guidelines on how to prevent SSIs, there is a need for standardization. This survey will investigate the disparity in SSI preventative measures between different surgical fields and countries.

4.
Dis Esophagus ; 36(11)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37291973

RESUMO

Previous studies recommend a watch-and-wait approach to paraesophageal hernia (PEH) repair due to an increased risk for mortality. While contemporary studies suggest that elective surgery is safe and effective, many patients presenting with PEH are elderly. Therefore, we assessed the impact of frailty on in-hospital outcomes and healthcare utilization among patients receiving PEH repair. This retrospective population-based cohort study assessed patients from the National Inpatient Sample database who received PEH repair between October 2015 to December 2019. Demographic and perioperative data were gathered, and frailty was measured using the 11-item modified frailty index. The outcomes measured were in-hospital mortality, complications, discharge disposition, and healthcare utilization. Overall, 10,716 patients receiving PEH repair were identified, including 1442 frail patients. Frail patients were less often female and were more often in the lowest income quartile compared to robust patients. Frail patients were at greater odds for in-hospital mortality [odds ratio (OR) 2.83 (95% CI 1.65-4.83); P < 0.001], postoperative ICU admissions [OR 2.07 (95% CI 1.55-2.78); P < 0.001], any complications [OR 2.18 (95% CI 1.55-2.78); P < 0.001], hospital length of stay [mean difference (MD) 1.75 days (95% CI 1.30-2.210; P < 0.001], and total admission costs [MD $5631.65 (95% CI $3300.06-$7.963.24); P < 0.001] relative to their robust patients. While PEH repair in elderly patients is safe and effective, frail patients have an increased rate of in-hospital mortality, postoperative ICU admissions, complications, and total admission costs. Clinicians should consider patient frailty when identifying the most appropriate surgical candidates for PEH repair.


Assuntos
Fragilidade , Hérnia Hiatal , Laparoscopia , Humanos , Feminino , Idoso , Fragilidade/complicações , Fragilidade/cirurgia , Estudos Retrospectivos , Herniorrafia/efeitos adversos , Estudos de Coortes , Hospitais , Aceitação pelo Paciente de Cuidados de Saúde , Hérnia Hiatal/complicações , Hérnia Hiatal/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Laparoscopia/efeitos adversos
5.
J Appl Microbiol ; 131(5): 2500-2515, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33966321

RESUMO

AIMS: To investigate the effects of three symbiotic Bradyrhizobium strains on peanut growth and on rhizobacterial communities in flowering and harvest stages in an organic farm, also to evaluate the role of plant development in influencing peanut rhizobacterial microbiota and correlations among the inoculants, rhizobacterial communities and plant growth. METHODS AND RESULTS: Peanut seeds were inoculated with three individual Bradyrhizobium strains, plant growth performance was measured in two developmental stages and rhizobacterial communities were analysed by Illumina sequencing of rpoB gene amplicons from peanut rhizosphere. The three bradyrhizobial inoculants significantly increased the nodule numbers and aboveground fresh weight of peanut plants regardless of the different growth stages, and the pod yields were increased to some extent and significantly positively correlated with Bradyrhizobium abundances in rhizosphere. Principal coordinate analysis indicated that the rhizobacterial communities were strongly influenced by the inoculation and peanut developmental stages. The bradyrhizobia inoculation increased relative abundances of potentially beneficial bacteria in peanut rhizosphere, and also altered rhizobacterial co-occurrence association networks and important network hub taxa. Similarly, plant development also significantly influenced the structure, composition and co-occurrence association networks of rhizobacterial communities. CONCLUSIONS: Bradyrhizobial inoculants increased peanut growth and yields, they and plant development affected the assembly of peanut rhizobacterial communities. SIGNIFICANCE AND IMPACT OF THE STUDY: Rhizobial inoculants improved the host plant performance that might also be associated with the dynamic changes in rhizobacterial community except enhancing the biological nitrogen fixation and helps to profoundly understand the mechanism how rhizobia inoculants improve plant growth and yields.


Assuntos
Bradyrhizobium , Fabaceae , Arachis , Bradyrhizobium/genética , Raízes de Plantas , Rizosfera , Microbiologia do Solo , Simbiose
6.
Eur Rev Med Pharmacol Sci ; 23(11): 4815-4821, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31210313

RESUMO

OBJECTIVE: Recently, long noncoding RNAs (lncRNAs) have got much attention for their role in tumor progression. LncRNA small nucleolar RNA host gene 7 (SNHG7) was studied in this research to identify how it affects the development of thyroid cancer (TC). PATIENTS AND METHODS: SNHG7 expression was detected by quantitative Real-time polymerase chain reaction (qRT-PCR) in both TC cells and tissue samples. Pearson's Chi-square test was used to determine the association of SNHG7 expression with several clinicopathological factors. Moreover, colony formation assay, cell proliferation and cell apoptosis assay were conducted. In addition, by performing qRT-PCR and Western blot assay, the underlying mechanism was explored. RESULTS: SNHG7 expression level was higher in TC samples than that in corresponding ones. The SNHG7 expression was associated with tumor size and TNM stage. Moreover, TC cell proliferation was inhibited, and TC cell apoptosis was induced after SNHG7 was knocked down in vitro. Moreover, the mRNA and protein expressions of brain-derived neurotrophic factor (BDNF) were downregulated after knockdown of SNHG7. Furthermore, the expression level of BDNF was positively related to the expression of SNHG7 in TC tissues. CONCLUSIONS: These results suggested that knockdown of SNHG7 could inhibit TC cell proliferation and induce cell apoptosis via downregulating BDNF, which might be a potential therapeutic target in TC.


Assuntos
Apoptose/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Regulação para Baixo/genética , RNA Longo não Codificante/genética , Neoplasias da Glândula Tireoide/genética , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proliferação de Células/genética , Células Cultivadas , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , RNA Longo não Codificante/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia
7.
Neoplasma ; 65(4): 592-598, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29940758

RESUMO

The value of adjuvant chemotherapy in T2N0 gastric cancer (GC) remains controversial. The aim of this retrospective study is to define a high-risk subgroup of pathological T2N0 GC patients and examine the impact of adjuvant chemotherapy on overall survival (OS). A total of 225 patients underwent R0 resection for T2N0 gastric adenocarcinoma between 2002 and 2012 and 51/225 (22.7%) of these received adjuvant chemotherapy. Multivariate Cox regression identified tumor location in the Upper1/3 of the stomach (peast one of the independent risk factor listed above, and we found that adjuvant chemotherapy significantly improved OS for this subgroup.


Assuntos
Adenocarcinoma/tratamento farmacológico , Quimioterapia Adjuvante , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/cirurgia , Escalas de Graduação Psiquiátrica Breve , Gastrectomia , Humanos , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/cirurgia
8.
Endocrinology ; 138(8): 3283-9, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9231779

RESUMO

Thyroid hormone receptors (TR) are ligand-activated transcription factors that modulate the expression of certain target genes in a developmental and tissue-specific manner. These specificities are determined by the tissue distribution of the TR isoforms alpha1 and beta1, the structure of the thyroid hormone response element (TRE) bound by the receptor, and heterodimerization partners. Among these, retinoid X receptors (RXR) have been recognized as the principal partners for TR. The present work reports the identification of a novel nuclear protein from 19-day-old embryonic rat brain that displays a distinct interaction pattern with TR isoforms at the level of the TRE of two genes known to be differentially expressed and regulated by thyroid hormone (T3): the ubiquitous malic enzyme and the brain-specific myelin basic protein. Electrophoretic gel mobility shift assays demonstrate that only TRbeta1 forms a specific complex with the rat brain nuclear factor on the myelin basic protein-TRE, but not on the malic enzyme-TRE. Thus, the interaction is selectively determined by both the receptor isoform and the structure of the TRE. The expression of this brain nuclear factor is restricted to the perinatal period, when myelination is sensitive to T3. Gel supershift assays with RXR-specific antibodies indicate that this factor is not one of the known RXR isoforms. However, it is most likely a new member of the RXR subfamily because it could be supershifted with an antibody raised against the highly conserved DNA-binding domain of RXRs.


Assuntos
Química Encefálica , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Proteínas Nucleares/análise , Receptores dos Hormônios Tireóideos/análise , Animais , Sequência de Bases , DNA/análise , DNA/genética , Regulação da Expressão Gênica no Desenvolvimento , Radioisótopos do Iodo , Isomerismo , Fígado/química , Fígado/embriologia , Fígado/crescimento & desenvolvimento , Masculino , Proteína Básica da Mielina/análise , Proteína Básica da Mielina/genética , Proteínas Nucleares/genética , Ratos , Ratos Sprague-Dawley , Receptores do Ácido Retinoico/análise , Receptores do Ácido Retinoico/genética , Receptores dos Hormônios Tireóideos/genética , Receptores X de Retinoides , Testículo/química , Testículo/embriologia , Testículo/crescimento & desenvolvimento , Tironinas/análise , Tironinas/genética , Fatores de Transcrição/análise , Fatores de Transcrição/genética , Transfecção
9.
J Bone Miner Res ; 10(5): 769-81, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7639112

RESUMO

Although 17 beta-estradiol (E2) replacement therapy has been shown to be effective in treating postmenopausal osteoporosis, the underlying mechanism remains unclear. The presence of low levels of functional endogenous estrogen receptor (ER) in some osteoblastic cells has been demonstrated, and the suggestion that the abundance of ER may be rate-limiting in the action of E2 on these cells has been made. To study the mechanism of ER in regard to E2-mediated effects, we stably transfected a human osteosarcoma cell line, SaOS-2, with an expression vector, pMV-7-ER, containing the human ER gene. We characterized six of the stably transfected clones. One of the stable clones, SaOS-2-ER, expressed extra copies of ER genes integrated into the genome as detected by Southern blot analysis, showed a significantly increased level of ER mRNA by RT-PCR, and contained an increased level of ER cytosolic protein as detected by an ER-specific EIA. The overexpressed ER was functional and sensitive to E2 in a dose-dependent fashion after transient transfection with a vector containing an estrogen response element (ERE) linked to a chloramphenicol acetyltransferase (CAT) reporter gene. Scatchard analysis revealed a single high-affinity binding site with a Kd similar to values obtained for the ER in MCF-7 breast cancer cells. These SaOS-2-ER cells had altered osteoblast phenotypic features including growth inhibition, decreased basal alkaline phosphatase activity, and decreased IL-6 expression and secretion. In response to E2, a greater than 2-fold increase in TGF-beta 1 mRNA was quantitatively measured in these ER-overexpressing osteoblasts. These cells may provide a sensitive and unique model for understanding the mechanism of E2 and ER in overall bone metabolism.


Assuntos
Neoplasias Ósseas/patologia , Regulação Neoplásica da Expressão Gênica/genética , Osteossarcoma/patologia , Receptores de Estrogênio/genética , Fosfatase Alcalina/metabolismo , Sequência de Bases , Sítios de Ligação , Northern Blotting , Southern Blotting , Neoplasias Ósseas/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Divisão Celular/genética , Cloranfenicol O-Acetiltransferase/análise , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Genes Reporter/genética , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Dados de Sequência Molecular , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteossarcoma/genética , Reação em Cadeia da Polimerase , RNA Mensageiro/química , RNA Mensageiro/genética , Receptores de Estrogênio/metabolismo , Transfecção , Fator de Crescimento Transformador beta/genética , Células Tumorais Cultivadas
10.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 15(2): 71-3, 1995 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-7787393

RESUMO

100 Patients with chronic renal failure(CRF) were treated mainly by the mediation principle (MP). Results showed that the progression of CRF with MP was slower than that without MP. There was very significant difference (P < 0.01) between the regression coefficient. In addition, the effect of MP on the factors in promoting the progression of CRF, e.g., hypertension, albuminuria, hyperlipemia and immune function etc. was discussed in detail.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Falência Renal Crônica/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Proteinúria/tratamento farmacológico
11.
Virology ; 172(1): 11-24, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2475970

RESUMO

Herpes simplex virus 1 (HSV-1) glycoprotein B (gB) is a multifunctional glycoprotein required for infectivity; it is thought to promote fusion of the viral envelope with the cell membrane and entry of virions into cells. To map the antigenic and functional domains on gB, we constructed amino terminal derivatives lacking the entire carboxyl terminus and internal deletion mutants lacking defined regions of the extracellular and transmembrane domains. Transient expression of the mutants in COS-1 cells revealed that the amino terminal derivatives were released into the medium whereas those with deletions in the extracellular domain were mostly retained within the transfected cells. Analysis of intact gB and the amino terminal derivatives showed that the intact molecule formed dimers whereas the mutant derivatives did not. Reactions of the derivatives with a panel of well-characterized monoclonal antibodies to gB showed that the neutralizing epitopes cluster in two domains. The first maps in the amino terminal 190 residues and contains seven continuous epitopes, five of which are HSV-1-specific. Reactions of antibodies with a set of oligopeptides fine-mapped the epitopes between residues 1 and 47. The second domain is composed of discontinuous epitopes and was expressed by amino terminal derivatives that were at least 457 residues in length or longer. Eleven epitopes map in this region, including those of four potent neutralizing antibodies whose cognitive sites mapped between residues 273 and 298 in mapping studies using antibody-resistant mutants. Results of the present study indicate that the cognitive sites of these antibodies are assembled into the discontinuous domain by juxtaposing residues from the amino-terminal half of gB monomers.


Assuntos
Simplexvirus/imunologia , Proteínas do Envelope Viral/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Transporte Biológico , Linhagem Celular , Chlorocebus aethiops , Análise Mutacional de DNA , Epitopos , Imunofluorescência , Dados de Sequência Molecular , Testes de Neutralização , Testes de Precipitina , Proteínas Recombinantes/imunologia , Mapeamento por Restrição , Simplexvirus/genética , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/ultraestrutura
12.
J Gen Virol ; 70 ( Pt 4): 979-85, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2471800

RESUMO

Cytomegalovirus (CMV) encodes several glycoproteins reported to be structural homologues of glycoproteins encoded by herpes simplex virus type 1 (HSV-1). To map the antigenic and functional domains on the 907 amino acid CMV glycoprotein B (gB), we cloned and expressed a subfragment of BamHI fragment R of the CMV (Towne) genome into an expression vector and reacted the resulting gene product with a panel of monoclonal antibodies. Our results showed that the DNA fragment encodes related glycoproteins which we previously designated gA and which others have reported to be homologous to HSV-1 gB in CMV (AD169). Analyses of the processing of CMV gB transiently expressed in eukaryotic cells showed that glycosylation occurred independently of viral infection. Ten antibodies with complement-dependent and independent neutralizing activity reacted with a truncated derivative of gB that contained 619 amino-terminal residues but lacked the transmembrane and intracellular regions of the molecule. Twelve additional antibodies reacted with a CHO cell line expressing a 680 amino-terminal derivative of gB. All of the reactive antibodies precipitated the 447 residue carboxy-terminal cleavage product of gB from extracts of CMV-infected cells. These results showed that the neutralizing epitopes map in at least two domains of gB which are located in a discontinuous segment of 219 amino acids between residues 461 and 680 from the amino terminus of the molecule.


Assuntos
Citomegalovirus/genética , Proteínas do Envelope Viral/genética , Citomegalovirus/imunologia , DNA Viral/análise , Epitopos/análise , Imunofluorescência , Humanos , Mapeamento por Restrição , Proteínas do Envelope Viral/imunologia
13.
Virology ; 166(2): 423-31, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2459843

RESUMO

To characterize the domains of HSV-1 glycoprotein B (gB), we isolated mutants resistant to monoclonal antibodies with potent neutralizing activity. Partial nucleotide sequencing of the mutations revealed that gB contains two domains comprising discontinuous and continuous amino acids that bind cross-reactive and type-specific neutralizing antibodies. Four mutations in a discontinuous domain, R1435, R233, R1375, and R126, contained substitutions of Tyr278 for His278, His298 for Arg298, Gln274 for Arg274, and Asn273 for Tyr273, respectively. Two mutations in a continuous domain, R1392 and R1397, contained substitutions of Thr32 for Ala32 and Thr47 for Asn47, respectively, and overlapped two other type-specific epitopes. Analysis of the nucleotide sequence of strain KOS showed differences from strain F at four residues proximal to the R1392 mutation and one residue proximal to the R1397 mutation, which explains the failure of HSV-1(F)-specific antibodies to these epitopes to react with KOS. One target site for proteolytic cleavage of gB by cellular enzymes maps at the amino terminus, partially overlapping four HSV-1-specific epitopes.


Assuntos
Anticorpos Antivirais/imunologia , Simplexvirus/imunologia , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Sequência de Bases , Linhagem Celular , Reações Cruzadas , Epitopos , Dados de Sequência Molecular , Mutação , Testes de Neutralização , Testes de Precipitina , Processamento de Proteína Pós-Traducional , Células Vero , Proteínas do Envelope Viral/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...