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1.
J Eur Acad Dermatol Venereol ; 35(7): 1434-1443, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34057249

RESUMO

This guideline intents to offer guidance on the diagnosis and management of patients with gastrointestinal symptoms and a suspected sexually transmitted cause. Proctitis is defined as an inflammatory syndrome of the anal canal and/or the rectum. Infectious proctitis can be sexually transmitted via genital-anal mucosal contact, but some also via digital contact and toys. Neisseria gonorrhoeae, Chlamydia trachomatis (including lymphogranuloma venereum), Treponema pallidum and herpes simplex virus are the most common sexually transmitted anorectal pathogens. Shigellosis can be transferred via oral-anal contact and may lead to proctocolitis or enteritis. Although most studies on these infections have concentrated on men who have sex with men (MSM), women having anal intercourse may also be at risk. A presumptive clinical diagnosis of proctitis can be made when there are symptoms and signs, and a definitive diagnosis when the results of laboratory tests are available. The symptoms of proctitis include anorectal itching, pain, tenesmus, bleeding, constipation and discharge in and around the anal canal. The majority of rectal chlamydia and gonococcal infections are asymptomatic and can only be detected by laboratory tests. Therefore, especially when there is a history of receptive anal contact, exclusion of anorectal infections is generally indicated as part of standard screening for sexually transmitted infections (STIs). Condom use does not guarantee protection from STIs, which are often spread without penile penetration. New in this updated guideline is: (i) lymphogranuloma venereum proctitis is increasingly found in HIV-negative MSM, (ii) anorectal Mycoplasma genitalium infection should be considered in patients with symptomatic proctitis after exclusion of other common causations such N. gonorrhoeae, C. trachomatis, syphilis and herpes, (iii) intestinal spirochetosis incidentally found in colonic biopsies should not be confused with syphilis, and (iv) traumatic causes of proctitis should be considered in sexually active patients.


Assuntos
Enterite , Infecções por Mycoplasma , Mycoplasma genitalium , Proctite , Proctocolite , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis , Chlamydia trachomatis , Feminino , Homossexualidade Masculina , Humanos , Masculino , Proctite/diagnóstico , Proctite/etiologia , Proctocolite/diagnóstico , Proctocolite/etiologia , Infecções Sexualmente Transmissíveis/diagnóstico
2.
Br J Oral Maxillofac Surg ; 59(2): 168-173, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32868122

RESUMO

Non-neoplastic jaw cyst (NJC) is one of the most common lesions in oral cavity, but there are only few detailed and extended epidemiological data based on the 2017 WHO classification. The aim of this study was to perform an epidemiological analysis of all NJCs treated from 1990 to 2019 at the Marche Polytechnic University, and to compare these data with those published in the literature. This retrospective study considered 2060 patients treated from 1990 to 2019. The NJCs were classified according to the 2017 WHO classification, and the main clinicopathological variables were analysed (sex, age, diagnosis, site of onset, size, and recurrences). Of 2150 total lesions, there were 2095 primary cysts and 55 recurrences; men are more frequently affected than women (M/F ratio of 1.73:1). The mean age of occurrence was 46.6 years, with a peak of frequency in the fifth decade. The mandible was more frequently involved than the maxilla, with a mean size of 1.9cm. Radicular cyst was the most frequently diagnosed cyst (56.6%), followed by dentigerous cyst (23.4%) and odontogenic keratocyst (12.9%). This is the first epidemiological study on NJCs in the Italian population according to 2017 WHO classification.


Assuntos
Cisto Dentígero , Cistos Maxilomandibulares , Cistos Odontogênicos , Feminino , Humanos , Itália/epidemiologia , Cistos Maxilomandibulares/diagnóstico por imagem , Cistos Maxilomandibulares/epidemiologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Cistos Odontogênicos/epidemiologia , Estudos Retrospectivos
3.
Clin Microbiol Infect ; 25(3): 380.e1-380.e7, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29906594

RESUMO

OBJECTIVES: Rapid and accurate sexually transmitted infection diagnosis can reduce onward transmission and improve treatment efficacy. We evaluated the accuracy of a 15-minute run-time recombinase polymerase amplification-based prototype point-of-care test (TwistDx) for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). METHODS: Prospective, multicentre study of symptomatic and asymptomatic patients attending three English sexual health clinics. Research samples provided were additional self-collected vulvovaginal swab (SCVS) (female participants) and first-catch urine (FCU) aliquot (female and male participants). Samples were processed blind to the comparator (routine clinic CT/NG nucleic acid amplification test (NAAT)) results. Discrepancies were resolved using Cepheid CT/NG GeneXpert. RESULTS: Both recombinase polymerase amplification and routine clinic NAAT results were available for 392 male and 395 female participants. CT positivity was 8.9% (35/392) (male FCU), 7.3% (29/395) (female FCU) and 7.1% (28/395) (SCVS). Corresponding NG positivity was 3.1% (12/392), 0.8% (3/395) and 0.8% (3/395). Specificity and positive predictive values were 100% for all sample types and both organisms, except male CT FCU (99.7% specificity (95% confidence interval (CI) 98.4-100.0; 356/357), 97.1% positive predictive value (95% CI 84.7-99.9; 33/34)). For CT, sensitivity was ≥94.3% for FCU and SCVS. CT sensitivity for female FCU was higher (100%; 95% CI, 88.1-100; 29/29) than for SCVS (96.4%; 95% CI, 81.7-99.9; 27/28). NG sensitivity and negative predictive values were 100% in FCU (male and female). CONCLUSIONS: This prototype test has excellent performance characteristics, comparable to currently used NAATs, and fulfils several World Health Organization ASSURED criteria. Its rapidity without loss of performance suggests that once further developed and commercialized, this test could positively affect clinical practice and public health.


Assuntos
Chlamydia trachomatis/isolamento & purificação , Neisseria gonorrhoeae/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/normas , Testes Imediatos , Infecções Sexualmente Transmissíveis/diagnóstico , Adolescente , Adulto , Idoso , Instituições de Assistência Ambulatorial , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Manejo de Espécimes , Adulto Jovem
4.
EBioMedicine ; 28: 120-127, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29396306

RESUMO

BACKGROUND: Rapid Point-Of-Care Tests for Chlamydia trachomatis (CT) may reduce onward transmission and reproductive sexual health (RSH) sequelae by reducing turnaround times between diagnosis and treatment. The io® single module system (Atlas Genetics Ltd.) runs clinical samples through a nucleic acid amplification test (NAAT)-based CT cartridge, delivering results in 30min. METHODS: Prospective diagnostic accuracy study of the io® CT-assay in four UK Genito-Urinary Medicine (GUM)/RSH clinics on additional-to-routine self-collected vulvovaginal swabs. Samples were tested "fresh" within 10days of collection, or "frozen" at -80°C for later testing. Participant characteristics were collected to assess risk factors associated with CT infection. RESULTS: CT prevalence was 7.2% (51/709) overall. Sensitivity, specificity, positive and negative predictive values of the io® CT assay were, respectively, 96.1% (95% Confidence Interval (CI): 86.5-99.5), 97.7% (95%CI: 96.3-98.7), 76.6% (95%CI: 64.3-86.2) and 99.7% (95%CI: 98.9-100). The only risk factor associated with CT infection was being a sexual contact of an individual with CT. CONCLUSIONS: The io® CT-assay is a 30-min, fully automated, high-performing NAAT currently CE-marked for CT diagnosis in women, making it a highly promising diagnostic to enable specific treatment, initiation of partner notification and appropriately intensive health promotion at the point of care.


Assuntos
Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/fisiologia , Genitália/microbiologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Feminino , Humanos , Estudos Prospectivos , Padrões de Referência , Fatores de Risco
5.
Ann R Coll Surg Engl ; 98(6): 425-30, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27138847

RESUMO

Introduction Tracheal stenosis following intubation is the most common indication for tracheal resection and reconstruction. Endoscopic dilation is almost always associated with recurrence. This study investigated first-line surgical resection and anastomosis performed in fit patients presenting with postintubation tracheal stenosis. Methods Between February 2011 and November 2014, a prospective study was performed involving patients who underwent first-line tracheal resection and primary anastomosis after presenting with postintubation tracheal stenosis. Results A total of 30 patients (20 male) were operated on. The median age was 23.5 years (range: 13-77 years). Seventeen patients (56.7%) had had previous endoscopic tracheal dilation, four (13.3%) had had tracheal stents inserted prior to surgery and one (3.3%) had undergone previous tracheal resection. Nineteen patients (63.3%) had had a tracheostomy. Eight patients (26.7%) had had no previous tracheal interventions. The median time of intubation in those developing tracheal stenosis was 20.5 days (range: 0-45 days). The median length of hospital stay was 10.5 days (range: 7-21 days). The success rate for anastomoses was 96.7% (29/30). One patient needed a permanent tracheostomy. The in-hospital mortality rate was 3.3%: 1 patient died from a chest infection 21 days after surgery. There was no mortality or morbidity in the group undergoing first-line surgery for de novo tracheal lesions. Conclusions First-line tracheal resection with primary anastomosis is a safe option for the treatment of tracheal stenosis following intubation and obviates the need for repeated dilations. Endoscopic dilation should be reserved for those patients with significant co-morbidities or as a temporary measure in non-equipped centres.


Assuntos
Anastomose Cirúrgica , Intubação Intratraqueal/efeitos adversos , Traqueia/cirurgia , Estenose Traqueal/cirurgia , Adolescente , Adulto , Idoso , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Adulto Jovem
6.
Eur J Histochem ; 59(1): 2455, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25820558

RESUMO

Osteonecrosis of the jaw (ONJ) is a chronic complication affecting long-term bisphosphonate-treated subjects, recognized by non-healing exposed bone in the maxillofacial region. The pathophysiological mechanism underlying ONJ has not been fully elucidated. The aim of the present study was to investigate the role of RANK/RANKL/OPG signaling pathway and, in parallel, to evaluate angiogenic and matrix mineralization processes in jaw bone necrotic samples obtained from bisphosphonate-treated subjects with established ONJ. Necrotic bone samples and native bone samples were processed for Light and Field Emission in Lens Scanning Electron Microscope (FEISEM) analyses, for Real-Time RT-PCR to evaluate the gene expression of TNFRSF11A (RANK), TNFSF11 (RANKL), and TNFSF11B (OPG) and for immunohistochemical analyses of VEGF and BSP expression. Morphological analyses performed by Light microscope and FEISEM show empty osteocytic lacunae and alteration of lamellar organization with degradation of the mineralized bone matrix in necrotic bone samples. A significant increase in TNFRSF11A, TNFSF11, TRAF6 and NFAT2 gene expression, and a reduction of TNFSF11B gene transcription level compared is also showed in necrotic bone compared to control samples. No significant difference of VEGF expression is evidenced, while lower BSP expression in necrotic bone compared to healthy samples is found. Even if the pathogenesis of bisphosphonate-associated ONJ remains unknown, a link between oral pathogens and its development seems to exist. We suppose lipopolysaccharide produced by bacteria colonizing and infecting necrotic bone and the surrounding viable area could trigger RANK/RANKL/OPG signaling pathway and, in this context, osteoclasts activation could be considered as a protective strategy carried out by the host bone tissue to delimitate the necrotic area and to counteract infection.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/fisiopatologia , Ligante RANK/fisiologia , Transdução de Sinais , Adulto , Idoso , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Ligante RANK/genética
7.
Int J Dent Hyg ; 12(3): 193-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24256458

RESUMO

AIM: The purpose of this study was to determine the influence of the place of living on periodontal status of 62 Down's syndrome (DS) subjects resident at home (DSH) or in specialized institutes (DSI) in central-eastern Italy. METHODS: The demographic characteristics of the subjects and the periodontal variables were evaluated according to their living conditions. Descriptive analyses were conducted by stratifying subjects into three age groups (0-13; 14-22; >23 years), using medians and 25th-75th percentiles to summarized data. Comparisons between DSH and DSI subjects were performed using Wilcoxon rank sum test. The effect of demographic and clinical variables on periodontal status was evaluated by means of quantile regression analysis. RESULTS: No significant differences resulted between DSH and DSI patients, when compared for gender, age and mental retardation. No significant differences were found in the periodontal variables for the subjects with 0-13 years, while DSI subjects between 14 and 22 years of age presented higher levels of plaque index, probing depth, clinical attachment loss and a lower number of surviving teeth compared to DSH subjects. When DSI and DSH groups ≥ 23 years of age were compared, no differences were observed in the periodontal conditions except for PI and the number of surviving teeth. Age, body mass index and severe mental retardation were found to be significant predictors of periodontal conditions. CONCLUSIONS: Institutionalization has a negative effect on surviving teeth number of Down's syndrome subjects. Furthermore, the home care seems to produce benefits on the periodontal conditions of DSH 14-22 years of age.


Assuntos
Síndrome de Down/complicações , Índice Periodontal , Características de Residência , Adolescente , Adulto , Fatores Etários , Perda do Osso Alveolar/classificação , Índice de Massa Corporal , Criança , Índice de Placa Dentária , Feminino , Humanos , Vida Independente , Institucionalização , Deficiência Intelectual/complicações , Itália , Masculino , Higiene Bucal/educação , Perda da Inserção Periodontal/classificação , Bolsa Periodontal/classificação , Perda de Dente/classificação , Escovação Dentária , Adulto Jovem
8.
Infection ; 42(1): 61-71, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24146352

RESUMO

PURPOSE: We have developed a sequencing assay for determining the usage of the genotypic HIV-1 co-receptor using peripheral blood mononuclear cell (PBMC) DNA in virologically suppressed HIV-1 infected patients. Our specific aims were to (1) evaluate the efficiency of V3 sequences in B versus non-B subtypes, (2) compare the efficiency of V3 sequences and tropism prediction using whole blood and PBMCs for DNA extraction, (3) compare the efficiency of V3 sequences and tropism prediction using a single versus a triplicate round of amplification. RESULTS: The overall rate of successful V3 sequences ranged from 100 % in samples with >3,000 copies HIV-1 DNA/10(6) PBMCs to 60 % in samples with <100 copies total HIV-1 DNA /10(6) PBMCs. Analysis of 143 paired PBMCs and whole-blood samples showed successful V3 sequences rates of 77.6 % for PBMCs and 83.9 % for whole blood. These rates are in agreement with the tropism prediction obtained using the geno2pheno co-receptor algorithm, namely, 92.1 % with a false-positive rate (FPR) of 10 or 20 % and of 96.5 % with an FPR of 5.75 %. The agreement between tropism prediction values using single versus triplicate amplification was 98.2 % (56/57) of patients using an FPR of 20 % and 92.9 % (53/57) using an FPR of 10 or 5.75 %. For 63.0 % (36/57) of patients, the FPR obtained via the single amplification procedure was superimposable to all three FPRs obtained by triplicate amplification. CONCLUSIONS: Our results show the feasibility and consistency of genotypic testing on HIV-1 DNA tropism, supporting its possible use for selecting patients with suppressed plasma HIV-1 RNA as candidates for CCR5-antagonist treatment. The high agreement between tropism prediction by single and triple amplification does not support the use of triplicate amplification in clinical practice.


Assuntos
Técnicas de Genotipagem/métodos , Infecções por HIV/virologia , HIV-1/genética , HIV-1/fisiologia , Técnicas de Diagnóstico Molecular/métodos , Receptores de HIV/metabolismo , Tropismo Viral , Adulto , DNA Viral/química , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Infecções por HIV/diagnóstico , HIV-1/classificação , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Provírus/classificação , Provírus/genética , Provírus/isolamento & purificação , Análise de Sequência de DNA , Internalização do Vírus
10.
Sex Transm Infect ; 85(3): 176-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19176570

RESUMO

OBJECTIVE: To determine the prevalence of rectal chlamydia infection in a cohort of men who have sex with men (MSM) and the proportion of infection that would be missed without routine screening. METHODS: MSM presenting to four HIV/GUM outpatient clinics at the Chelsea & Westminster Hospital NHS Foundation Trust between 1 November 2005 and 29 September 2006 were offered testing for rectal chlamydia infection in addition to their routine screen for sexually transmitted infections (STIs). Chlamydia trachomatis (CT) tests were performed using the Beckton-Dickinson Probe-Tec Strand Displacement Assay. Positive samples were re-tested at the Sexually Transmitted Bacteria Reference Laboratory, to confirm the result and identify lymphogranuloma venereum (LGV)-associated serovars. RESULTS: A total of 3076 men were screened. We found an 8.2% prevalence of infection with CT (LGV and non-LGV serovars) in the rectum and 5.4% in the urethra. The HIV and rectal chlamydia co-infection rate was 38.1%. The majority of rectal infections (69.2%, (171/247)) were asymptomatic and would have been missed if routine screening had not been undertaken. Of the samples re-tested, 94.2% (227/242) rectal and 91.8% (79/86) urethral specimens were confirmed CT positive and 36 cases of LGV were identified. CONCLUSION: Our data show a high rate of rectal chlamydia infection, in the majority of cases it was asymptomatic. We recommend routine screening for rectal chlamydia in men at risk, as this may represent an important reservoir for the onward transmission of infection.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Homossexualidade Masculina , Doenças Retais/epidemiologia , Doenças Uretrais/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Chlamydia/epidemiologia , Estudos de Coortes , Testes Diagnósticos de Rotina , Infecções por HIV/epidemiologia , Humanos , Londres/epidemiologia , Linfogranuloma Venéreo/diagnóstico , Linfogranuloma Venéreo/epidemiologia , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Prevalência , Doenças Retais/diagnóstico , Reto/microbiologia , Uretra/microbiologia , Doenças Uretrais/diagnóstico , Adulto Jovem
11.
Int J STD AIDS ; 18(6): 404-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17609031

RESUMO

Our department has been offering routine rectal chlamydia testing to all individuals reporting ano-receptive sex since 2002. We wanted to determine the prevalence of rectal chlamydia and if there were any factors associated with a positive diagnosis. A retrospective case-notes analysis was performed of all individuals tested for rectal chlamydia from November 2002 until March 2005. In total, 1187 case-notes were examined. Overall, the prevalence of chlamydia infection was 8.5%; in asymptomatic individuals, it was 5.1%. There was a positive association with chlamydia infection in patients who were HIV-positive, those who reported rectal symptoms and from samples in which microscopy of a rectal smear demonstrated >10 polymorphonuclear cells/high power field. The findings support our continuing to offer rectal chlamydia screening to patients attending our service. Chlamydia trachomatis infection should be considered as a possible diagnosis in patients who present with rectal symptoms outside a genitourinary medicine clinic setting.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Doenças Retais/microbiologia , Adulto , Instituições de Assistência Ambulatorial , Infecções por Chlamydia/epidemiologia , Infecções por Chlamydia/microbiologia , Feminino , Gonorreia/diagnóstico , Gonorreia/epidemiologia , Gonorreia/microbiologia , Humanos , Masculino , Programas de Rastreamento/métodos , Microscopia/métodos , Doenças Retais/epidemiologia , Estudos Retrospectivos , Comportamento Sexual , Reino Unido/epidemiologia
12.
Int J Gynecol Cancer ; 14(5): 980-3, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15361212

RESUMO

OBJECTIVE: The aim of this study was to evaluate the probable usefulness of normal beta-human chorionic gonadotropin (beta-hCG) regression curve in the diagnosis of persistent trophoblastic disease (PTD). METHODS: A log-value regression curve was developed from the means and 95% confidence limits of serial weekly serum beta-hCG titers of 43 patients with uneventful complete hydatidiform moles and 14 patients, who were previously confirmed as PTD. RESULTS: All 14 PTD patients (100%) had abnormal values, beyond normal range, within 4 weeks. beta-hCG was in its upper values, compared to normal regression curve at 2.29 +/- 0.19 weeks. This was earlier than plateau or rise detection at 4.21 +/- 0.33 weeks (P < 0.001). Within 3 weeks of evacuation, 13 of 14 (92.86%) PTD patients' beta-hCG values exceeded the normal range, whereas only six of 14 (42%) showed a rise or plateau. CONCLUSION: Our finding indicates that the normal beta-hCG regression curve may be useful for quicker detection of PTD than the plateau or rise of level.


Assuntos
Biomarcadores Tumorais/análise , Gonadotropina Coriônica Humana Subunidade beta/sangue , Doença Trofoblástica Gestacional/diagnóstico , Mola Hidatiforme/diagnóstico , Neoplasias Uterinas/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Doença Trofoblástica Gestacional/patologia , Humanos , Mola Hidatiforme/patologia , Irã (Geográfico) , Gravidez , Valores de Referência , Análise de Regressão , Neoplasias Uterinas/patologia
13.
J Clin Pediatr Dent ; 28(1): 89-93, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14604150

RESUMO

The objective of this study was to evaluate long term effects of orofacial regulation therapy with modified Castillo-Morales palatal plate on 68 Down children that attended our Unit from 1992 to 2001. Corrections obtained with palatal plate therapy were evaluated according to the following parameters: spontaneous lingual protrusion based on three level scale, position "open mouth", labial hypotonia and sialorrhea. The results showed distinct improvement in nearly all of the parameters compared to initial conditions.


Assuntos
Síndrome de Down/fisiopatologia , Músculos Faciais/fisiopatologia , Terapia Miofuncional/instrumentação , Pré-Escolar , Síndrome de Down/complicações , Humanos , Lactente , Macroglossia/fisiopatologia , Macroglossia/terapia , Hipotonia Muscular/etiologia , Hipotonia Muscular/terapia , Aparelhos Ortodônticos Removíveis , Palato Duro , Estimulação Física/instrumentação , Sialorreia/etiologia , Sialorreia/terapia , Língua/fisiopatologia
14.
Biochem Biophys Res Commun ; 289(5): 1125-34, 2001 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-11741309

RESUMO

A direct binding of HRC (histidine-rich Ca(2+)-binding protein) to triadin, the main transmembrane protein of the junctional sarcoplasmic reticulum (SR) of skeletal muscle, seems well supported. Opinions are still divided, however, concerning the triadin domain involved, either the cytoplasmic or the lumenal domain, and the exact role played by Ca(2+), in the protein-to-protein interaction. Further support for colocalization of HRC with triadin cytoplasmic domain is provided here by experiments of mild tryptic digestion of tightly sealed TC vesicles. Accordingly, we show that HRC is preferentially phosphorylated by endogenous CaM K II, anchored to SR membrane on the cytoplasmic side, and not by lumenally located casein kinase 2. We demonstrate that HRC can be isolated as a complex with triadin, following equilibrium sucrose-density centrifugation in the presence of mM Ca(2+). Here, we characterized the COOH-terminal portion of rabbit HRC, expressed and purified as a fusion protein (HRC(569-852)), with respect to Ca(2+)-binding properties, and to the interaction with triadin on blots, as a function of the concentration of Ca(2+). Our results identify the polyglutamic stretch near the COOH terminus, as the Ca(2+)-binding site responsible, both for the acceleration in mobility of HRC on SDS-PAGE in the presence of millimolar concentrations of Ca(2+), and for the enhancement by high Ca(2+) of the interaction between HRC and triadin cytoplasmic segment. (c)2001 Elsevier Science.


Assuntos
Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/metabolismo , Cálcio/metabolismo , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Animais , Sítios de Ligação , Proteínas de Ligação ao Cálcio/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas Quinases Dependentes de Cálcio-Calmodulina/química , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Estabilidade de Medicamentos , Técnicas In Vitro , Cinética , Substâncias Macromoleculares , Ligação Proteica , Estrutura Terciária de Proteína , Coelhos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Retículo Sarcoplasmático/metabolismo
15.
Mol Cell Biochem ; 223(1-2): 139-45, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11681715

RESUMO

Skeletal muscle triadin is a sarcoplasmic reticulum (SR) membrane protein that had been shown to interact structurally and functionally at the cytoplasmic domain (amino acid residues 1-47) with the ryanodine receptor (RyR1), and to undergo phosphorylation by endogenous calmodulin protein kinase (CaM K II) in isolated terminal cisternae from rabbit fast-twitch muscle. Here we show that triadin cytoplasmic domain expressed as glutathione-S-transferase fusion protein, is a substrate of the protein kinase. This finding is corroborated by identification of a specific consensus sequence in the deduced amino sequence between residue 34 and 37 of triadin. Confirming the regulatory features of CaM K II, we show the phosphorylation of triadin cytoplasmic segment by the kinase, when converted to the autonomous form. We propose that triadin modulates RyR1 in a phosphorylation-dependent manner.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas de Transporte/metabolismo , Fibras Musculares de Contração Rápida/metabolismo , Proteínas Musculares/metabolismo , Retículo Sarcoplasmático/metabolismo , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas de Transporte/química , Vesículas Citoplasmáticas/metabolismo , Genes Reporter , Imuno-Histoquímica , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Fibras Musculares de Contração Rápida/citologia , Proteínas Musculares/química , Fosforilação , Estrutura Terciária de Proteína , Coelhos , Proteínas Recombinantes de Fusão/metabolismo , Retículo Sarcoplasmático/enzimologia
16.
Exp Cell Res ; 265(1): 104-13, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11281648

RESUMO

The glycoprotein calsequestrin (CS) is segregated to the junctional sarcoplasmic reticulum (jSR) and is responsible for intraluminal Ca(2+) binding. A chimeric CS-hemoagglutinin 1 (HA1), obtained by adding the nine amino acid viral epitope hemoagglutinin to the carboxy terminal of CS and shown to be correctly segregated to skeletal muscle jSR [A. Nori, K. A. Nadalini, A. Martini, R. Rizzuto, A. Villa, and P. Volpe (1997). Chimeric calsequestrin and its targeting to the junctional sarcoplasmic reticulum of skeletal muscle. Am. J. Physiol. 272, C1420-C1428] lends itself as a molecular tool to investigate the targeting domains of CS. A putative targeting mechanism of CS to jSR implies glycosylation-dependent steps in the endoplasmic reticulum (ER) and Golgi complex. To test this hypothesis, CS-HA1DeltaGly, a mutant in which the unique N-glycosylation site Asn316 was changed to Ile, was engineered by site-directed mutagenesis. The mutant cDNA was transiently transfected in either HeLa cells, myoblasts of rat skeletal muscle primary cultures, or regenerating soleus muscle fibers of adult rats. The expression and intracellular localization of CS-HA1DeltaGly was studied by double-labeling epifluorescence by means of antibodies against either CS, HA1, or the ryanodine receptor calcium release channel. CS-HA1DeltaGly was expressed and retained to ER and ER/sarcoplasmic reticulum of HeLa cells and myotubes, respectively, and expressed, sorted, and correctly segregated to jSR of regenerating soleus muscle fibers. Thus, the targeting mechanism of CS in vivo appears not to be affected by glycosylation-that is, the sorting, docking, and segregation of CS are independent of cotranslational and posttranslational glycosylation or glycosylations.


Assuntos
Calsequestrina/metabolismo , Glicoproteínas/metabolismo , Retículo Sarcoplasmático/metabolismo , Animais , Sítios de Ligação , Calsequestrina/genética , Células Cultivadas , Retículo Endoplasmático/metabolismo , Expressão Gênica , Glicoproteínas/genética , Glicosilação , Células HeLa , Hemaglutininas Virais/genética , Humanos , Músculo Esquelético/metabolismo , Coelhos , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transfecção
17.
Exp Cell Res ; 260(1): 40-9, 2000 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11010809

RESUMO

Calsequestrin (CS) is segregated to the junctional sarcoplasmic reticulum (jSR) of skeletal muscle fibers and is responsible for intraluminal Ca(2+) binding. A chimeric CS-HA1, obtained by adding the nine-amino-acid viral epitope hemagglutinin (HA1) to the carboxy-terminal of CS and shown to be correctly segregated to skeletal muscle jSR in vivo (A. Nori, K. A. Nadalini, A. Martini, R. Rizzuto, A. Villa, and P. Volpe, 1997, Am. J. Physiol. 272, C1420-C1428), is mutagenized in order to identify domains of CS involved in targeting. Since a putative targeting mechanism of CS implies phosphorylation-dependent steps in the endoplasmic reticulum (ER) and/or Golgi complex, five CS-HA1 mutants disrupting the three phosphorylation sites of CS (Thr(189), Thr(229), and Thr(353)) were engineered by either site-directed mutagenesis or deletion: CS-HA1DeltaP1 (Thr(189) --> Ile); CS-HA1DeltaP2 (Thr(229) --> Asn); CS-HA1DeltaP1,2; in which Thr(189) and Thr(229) were changed to Ile and Asn, respectively; and CS-HA1Delta14(COOH) and CS-HA1Delta49 (COOH), in which 14 residues (Glu(354)-Asp(367)) and 49 residues (Asp(319)-Asp(367)), respectively, were deleted at the carboxy-terminal. Mutant cDNAs were transiently transfected in either HeLa cells, cultured myoblasts of rat skeletal muscle, or regenerating soleus muscle fibers of adult rats. Each CS-HA1 mutant was identified by Western blot as a single polypeptide of the predicted molecular weight. The intracellular localization of CS-HA1 mutants was studied by immunofluorescence using specific antibodies against either CS or HA1. CS-HA1 mutants colocalized with ER markers, e.g., calreticulin, and partially overlapped with Golgi complex markers, e.g., alpha-mannosidase II, in HeLa cells and myotubes. CS-HA1 mutants were expressed and retained in ER and ER/SR of HeLa cells and myotubes, respectively, and correctly segregated to jSR of regenerating soleus muscle fibers. Thus, the targeting mechanism of CS in vivo is not affected by phosphorylation(s); i.e., sorting and segregation of CS appear to be independent of posttranslational phosphorylation(s).


Assuntos
Calsequestrina/genética , Calsequestrina/metabolismo , Músculo Esquelético/metabolismo , Retículo Sarcoplasmático/metabolismo , Animais , Sequência de Bases , Sítios de Ligação/genética , Células Cultivadas , Primers do DNA/genética , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Células HeLa , Humanos , Masculino , Microscopia de Fluorescência , Mutagênese Sítio-Dirigida , Fosforilação , Ratos , Ratos Wistar , Regeneração , Deleção de Sequência , Transfecção
18.
Am J Physiol ; 277(5): C974-81, 1999 11.
Artigo em Inglês | MEDLINE | ID: mdl-10564090

RESUMO

Calsequestrin (CS) is the Ca(2+) binding protein of the junctional sarcoplasmic reticulum (jSR) lumen. Recently, a chimeric CS-HA1, obtained by adding the nine-amino-acid viral epitope hemagglutinin (HA1) to the COOH terminus of CS, was shown to be correctly segregated to the sarcoplasmic reticulum [A. Nori, K. A. Nadalini, A. Martini, R. Rizzuto, A. Villa, and P. Volpe. Am. J. Physiol. 272 (Cell Physiol. 41): C1420-C1428, 1997]. A putative targeting mechanism of CS to jSR implies electrostatic interactions between negative charges on CS and positive charges on intraluminal domains of jSR integral proteins, such as triadin and junctin. To test this hypothesis, 2 deletion mutants of chimeric CS were engineered: CS-HA1DeltaGlu-Asp, in which the 14 acidic residues [-Glu-(Asp)(5)-Glu-(Asp)(7)-] of the COOH-terminal tail were removed, and CS-HA1Delta49(COOH), in which the last, mostly acidic, 49 residues of the COOH terminus were removed. Both mutant cDNAs were transiently transfected in HeLa cells, myoblasts of rat skeletal muscle primary cultures, or regenerating soleus muscle fibers of adult rats. The expression and intracellular localization of CS-HA1 mutants were studied by epifluorescence microscopy with use of antibodies against CS or HA1. CS-HA1 mutants were shown to be expressed, sorted, and correctly segregated to jSR. Thus short or long deletions of the COOH-terminal acidic tail do not influence the targeting mechanism of CS.


Assuntos
Calsequestrina/genética , Calsequestrina/metabolismo , Sinais Direcionadores de Proteínas/química , Retículo Sarcoplasmático/metabolismo , Ácidos , Fatores Etários , Animais , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Calsequestrina/química , Cristalografia , DNA Complementar , Imunofluorescência , Deleção de Genes , Expressão Gênica/fisiologia , Células HeLa , Humanos , Masculino , Fibras Musculares Esqueléticas/química , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/fisiologia , Mutagênese/fisiologia , Sinais Direcionadores de Proteínas/metabolismo , Estrutura Terciária de Proteína , Ratos , Ratos Wistar , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Regeneração , Retículo Sarcoplasmático/química , Transfecção
19.
J Egypt Soc Parasitol ; 29(3): 849-57, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-12561924

RESUMO

An enzyme-linked immunoelectrotransfer blot (EITB) test was assessed for diagnosis of 47 pulmonary cystic echinococcosis (CE) cases admitted to Ain Shams University Hospitals for Surgery. Diagnosis of these cases was established on clinical examination, X-ray, sonography and indirect hemagglutination (IHA) test, which was negative in four cases (sensitivity 91.5%). Sera from patients with other parasitic infections, carcinomas or normal sera were used as controls. Human and Camel hydatid cyst fluids were used as antigens after separation and characterization of their antigenic components using 12.5% SDS-PAGE under reducing conditions. Six molecular weight antigens with molecular masses approximately 7, 20, 28, 35 and 127 kDa were of diagnostic importance. They were strongly recognized by sera of all CE patients specially with camel hydatid cyst fluid (HCF) giving a 100% sensitivity to the EITB test. Sera of patients with other parasitic infections as well as carcinomas and normal control sera couldn't recognize any of the above antigens and therefore were negative for the test. This results in 100% specificity of the EITB test. These data support the concept that EITB using camel hydatid fluid is a good diagnostic test for cystic echinococcosis.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/imunologia , Líquidos Corporais/imunologia , Equinococose Pulmonar/diagnóstico , Echinococcus/imunologia , Animais , Antígenos de Helmintos/química , Camelus/parasitologia , Equinococose Pulmonar/veterinária , Ensaio de Imunoadsorção Enzimática , Humanos , Immunoblotting , Sensibilidade e Especificidade
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