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1.
World J Urol ; 36(8): 1241-1246, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29523948

RESUMO

PURPOSE: To measure the usage rate of social media (SoMe) resources in the prostate cancer community, we performed a comprehensive quantitative and qualitative assessment of SoMe activity on the topic of PCa on the four most frequented platforms. METHODS: We scanned the SoMe platforms Facebook, Twitter, YouTube, and Instagram for "prostate cancer" as a cross-sectional analysis or during a defined time period. Sources were included if their communication centered on PCa by title and content. We assessed activity measurements for each SoMe source and classified the sources into six functional categories. RESULTS: We identified 99 PCa-related Facebook groups that amassed 31,262 members and 90 Facebook pages with 283,996 "likes". On YouTube, we found 536 PCa videos accounting for 43,966,634 views, 52,655 likes, 8597 dislikes, and 12,393 comments. During a 1-year time period, 32,537 users generated 110,971 tweets on #ProstateCancer on Twitter, providing over 544 million impressions. During a 1-month time period, 638 contributors posted 1081 posts on Instagram, generating over 22,000 likes and 4,748,159 impressions. Among six functional categories, general information/support dominated the SoMe landscape on all SoMe platforms. CONCLUSION: SoMe activity on the topic of PCa on the four most frequented platforms is high. Facebook groups, YouTube videos, and Twitter tweets are mainly used for giving general information on PCa and education. High SoMe utilization in the PCa community underlines its future role for communication of PCa.


Assuntos
Neoplasias da Próstata , Mídias Sociais/estatística & dados numéricos , Estudos Transversais , Humanos , Masculino
2.
World J Urol ; 35(7): 1015-1022, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27830373

RESUMO

PURPOSE: Comparing the accuracy of MRI/ultrasound-guided target-biopsy by transrectal biopsy (TRB) with elastic versus rigid image fusion versus transperineal biopsy (TPB) with rigid image fusion in a standardized setting. METHODS: Target-biopsy of six differently sized and located lesions was performed on customized CIRS 070L prostate phantoms. Lesions were only MRI-visible. After prior MRI for lesion location, one targeted biopsy per lesion was obtained by TRB with elastic image fusion with Artemis™ (Eigen, USA), TRB with rigid image fusion with real-time virtual sonography (Hitachi, Japan) and TPB with rigid image fusion with a brachytherapy approach (Elekta, Sweden), each on a phantom of 50, 100 and 150 ml prostate volume. The needle trajectories were marked by contrast agent and detected in a postinterventional MRI. RESULTS: Overall target detection rate was 79.6% with a slight superiority for the TPB (83.3 vs. 77.8 vs. 77.8%). TRB with elastic image fusion showed the highest overall precision [median distance to lesion center 2.37 mm (0.14-4.18 mm)], independent of prostate volume. Anterior lesions were significantly more precisely hit than transitional and basal lesions (p = 0.034; p = 0.015) with comparable accuracy for TRB with elastic image fusion and TPB. In general, TRB with rigid image fusion was inferior [median 3.15 mm (0.37-10.62 mm)], particularly in small lesions. CONCLUSION: All biopsy techniques allow detection of clinically significant tumors with a median error of 2-3 mm. Elastic image fusion appears to be the most precise technique, independent of prostate volume, target size or location.


Assuntos
Biópsia Guiada por Imagem , Imagens de Fantasmas , Próstata , Neoplasias da Próstata , Pesquisa Comparativa da Efetividade , Precisão da Medição Dimensional , Humanos , Biópsia Guiada por Imagem/instrumentação , Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Design de Software , Ultrassonografia de Intervenção/instrumentação , Ultrassonografia de Intervenção/métodos
3.
World J Urol ; 31(1): 183-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22885617

RESUMO

INTRODUCTION AND OBJECTIVE: Fluoroscopy time influences radiation exposure of both surgeons and patients during endourological interventions. Changes in fluoroscopy habits of endourological surgeons after being informed about their fluoroscopy times were evaluated depending on their endourological experience. MATERIALS AND METHODS: From April 2010 to April 2011, 402 endourological interventions in 337 Patients were assessed. Evaluated interventions were ureter stent placement (USP), ureter stent change (USC) nephrostomy change (NC), ureterorenoscopy (URS) and percutaneous nephrolithotomy (PCNL). Fluoroscopy time (FT) and operation time (OT) were recorded. For USP, USC and NC, the surgeons were divided into two groups: group I with >2 years of endourological experience and group II with <2 years experience. URS and PCNL only were performed by experienced surgeons. After 6 months, all surgeons were informed about their mean detected results. Both groups were compared, and changes in FT and OT in the second part of the study were analysed. RESULTS: Surgeons reduced their median fluoroscopy times up to 55 % after being informed about their fluoroscopy manners. Experienced surgeons reduced both operation and fluoroscopy times significantly for USP, USC and NC. For URS and PCNL, and OT and FT, the differences were not statistically significant. Inexperienced surgeons were not able to reduce both OT and FT significantly. CONCLUSION: If experienced surgeons are informed about their fluoroscopy time during endourological interventions, fluoroscopy times can be reduced significantly in easy procedures, which leads to less radiation exposure of surgeons and patients. Inexperienced surgeons have less possibility to influence their fluoroscopy manners.


Assuntos
Endoscopia/estatística & dados numéricos , Fluoroscopia , Lesões por Radiação/prevenção & controle , Procedimentos Cirúrgicos Urológicos/normas , Competência Clínica , Feminino , Fluoroscopia/efeitos adversos , Fluoroscopia/estatística & dados numéricos , Humanos , Masculino , Duração da Cirurgia , Fatores de Tempo
4.
World J Urol ; 31(3): 579-84, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23053214

RESUMO

BACKGROUND: Microbial ureteral stent colonisation (MUSC) is one leading risk factor for complications associated with ureteral stent placement. As MUSC remains frequently undetected by standard urine cultures, its definitive diagnosis depends on microbiological investigation of the stent. However, a standard reference laboratory technique for studying MUSC is still lacking. MATERIALS AND METHODS: A total of 271 ureteral stents removed from 199 consecutive patients were investigated. Urine samples were obtained prior to device removal. Stents were divided into four parts. Each part was separately processed by the microbiology laboratory within 6 h. Ureteral stents were randomly allocated to roll-plate or sonication, respectively, and analysed using standard microbiological techniques. Demographic and clinical data were prospectively collected using a standard case-report form. RESULTS: Overall, roll-plate showed a higher detection rate of MUSC compared with sonication (35 vs. 28 %, p < 0.05) and urine culture (35 vs. 8 %, p < 0.05). No inferiority of Maki's technique was observed even when stents were stratified according to indwelling time below or above 30 days. Compared with roll-plate, sonication commonly failed to detect Enterococcus spp., coagulase-negative staphylococci (CoNS) and Enterobacteriaceae. In addition, sonication required more hands-on time, more equipment and higher training than roll-plate in the laboratory. CONCLUSIONS: This prospective randomised study demonstrates the superiority of Maki's roll-plate technique over sonication in the diagnosis of MUSC and that urine culture is less sensitive than both methods. The higher detection rate, simplicity and cost-effectiveness render roll-plate the methodology of choice for routine clinical investigation as well as basic laboratory research.


Assuntos
Infecções Relacionadas a Cateter/diagnóstico , Infecções por Enterobacteriaceae/diagnóstico , Enterobacteriaceae/isolamento & purificação , Enterococcus/isolamento & purificação , Técnicas Microbiológicas/métodos , Infecções Estreptocócicas/diagnóstico , Cateteres Urinários/microbiologia , Adulto , Idoso , Infecções Relacionadas a Cateter/microbiologia , Contagem de Colônia Microbiana , Análise Custo-Benefício , Infecções por Enterobacteriaceae/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Sonicação/métodos , Infecções Estreptocócicas/microbiologia , Urina/microbiologia
5.
Br J Cancer ; 106(8): 1395-405, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22460269

RESUMO

BACKGROUND: Colorectal cancers are often chemoresistant toward antitumour drugs that are substrates for ABCB1-mediated multidrug resistance (MDR). Activation of the Wnt/ß-catenin pathway is frequently observed in colorectal cancers. This study investigates the impact of activated, gain-of-function ß-catenin on the chemoresistant phenotype. METHODS: The effect of mutant (mut) ß-catenin on ABCB1 expression and promoter activity was examined using HCT116 human colon cancer cells and isogenic sublines harbouring gain-of-function or wild-type ß-catenin, and patients' tumours. Chemosensitivity towards 24 anticancer drugs was determined by high throughput screening. RESULTS: Cell lines with mut ß-catenin showed high ABCB1 promoter activity and expression. Transfection and siRNA studies demonstrated a dominant role for the mutant allele in activating ABCB1 expression. Patients' primary colon cancer tumours shown to express the same mut ß-catenin allele also expressed high ABCB1 levels. However, cell line chemosensitivities towards 24 MDR-related and non-related antitumour drugs did not differ despite different ß-catenin genotypes. CONCLUSION: Although ABCB1 is dominantly regulated by mut ß-catenin, this did not lead to drug resistance in the isogenic cell line model studied. In patient samples, the same ß-catenin mutation was detected. The functional significance of the mutation for predicting patients' therapy response or for individualisation of chemotherapy regimens remains to be established.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Mutantes/genética , beta Catenina/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Humanos , Imuno-Histoquímica , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real
6.
Transpl Infect Dis ; 14(1): 57-63, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22093165

RESUMO

Ureteral stent insertion at the time of renal transplantation significantly decreases complications of urine leakage and obstruction, but bears an intrinsic risk of microbial colonization. Associated urinary tract infection (UTI) may pose a significant risk for graft infection and subsequent graft failure, in particular, during high-level immunosuppression in the early phase after transplantation. The aims of this prospective study were (i) to assess the frequency of microbial ureteral stent colonization (MUSC) in renal transplant recipients by sonication, (ii) to compare the diagnostic value of sonication with that of conventional urine culture (CUC), (iii) to determine biofilm forming organisms, and (iv) to investigate the influence of MUSC on the short-time functional outcome. A total of 80 ureteral stents from 78 renal transplant recipients (deceased donors n = 50, living donors n = 28) were prospectively included in the study. CUC was obtained prior to renal transplantation and at ureteral stent removal. In addition, a new stent sonication technique was performed to dislodge adherent microorganisms. CUCs were positive in 4% of patients. Sonicate-fluid culture significantly increased the yield of microbial growth to 27% (P < 0.001). Most commonly isolated microorganisms by sonication were Enterococcus species (31%), coagulase-negative staphylococci (19%), and Lactobacillus species (19%), microorganisms not commonly observed in UTIs after renal transplantation. The median glomerular filtraton rate (GFR) of the study population increases from 39 mL/min immediately after transplantation (time point A) to 50 mL/min 6 month post transplantation (time point B). In patients without MUSC, the GFR improves from 39 mL/min (A) to 48 mL/min (B) and in patients with MUSC from 39 mL/min (A) to 50 mL/min (B), respectively. In summary, MUSC in renal transplant recipients is common and remains frequently undetected by routine CUC, but colonization had no measurable effect on renal function.


Assuntos
Transplante de Rim/efeitos adversos , Sonicação/métodos , Stents/microbiologia , Ureter/cirurgia , Infecções Urinárias/microbiologia , Adulto , Biofilmes/crescimento & desenvolvimento , Meios de Cultura , Feminino , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Stents/efeitos adversos , Infecções Urinárias/epidemiologia , Infecções Urinárias/etiologia , Urina/microbiologia
7.
Urologe A ; 60(3): 331-336, 2021 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-33559693

RESUMO

BACKGROUND: Surgery is challenging during the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to investigate the preoperative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing in elective and emergency surgery and to calculate the patient contacts during hospital stay. MATERIALS AND METHODS: All surgeries defined by the German procedural classification (starting with a 5) from 1 June until 29 November 2020 were retrospectively evaluated regarding the preoperative SARS-CoV­2 nasopharyngeal swab test. The results were then divided in emergency and elective surgeries. To show the personal contacts of the patients in a university hospital, we calculated the patient pathway within the department of urology and urosurgery for April 2020. Therefor we used the electronic patient records. RESULTS: Altogether 7745 surgical procedures in 5985 patients were performed, whereby 39 (0.5%) SARS-CoV­2 tests were positive. 2833 (37%) surgical procedures were emergency cases and 4912 (63%) were elective procedures. 25 (0.9%) of the emergency group and 14 (0.3%) of the elective surgeries had a positive SARS-CoV­2 test. The average number of contacts in the patient room was 12.83 (0-50) and 84.22 (0-249) at the ward level, not counting contacts with the clinic staff. CONCLUSIONS: Nearly 1% of the preoperative SARS-CoV­2 tests of either emergency or elective surgeries tested positive in the 6 months prior to November 2020. Although the risk of undetected SARS-CoV­2 infection appears to be low in terms of costs and personnel, preoperative screening is useful in high-risk areas to ensure further necessary surgeries, especially concerning cancer patients and to prevent virus spread in a hospital.


Assuntos
COVID-19 , Coronavirus , Teste para COVID-19 , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2
8.
Trials ; 22(1): 236, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33781339

RESUMO

BACKGROUND: Data from interventional studies suggest that a peritoneal flap after pelvic lymph node dissection (LND) during laparoscopic, robotic-assisted radical prostatectomy (RARP) may reduce the rate of symptomatic lymphoceles in transperitoneal approach. However, most of these studies are not conducted in a randomized controlled fashion, thus limiting their scientific value. A recent prospective, randomized, controlled trial (RCT) did not show superiority of a peritoneal flap while further trials are lacking. Therefore, the aim of the presented RCT will be to show that creating a peritoneal flap decreases the rate of symptomatic lymphoceles compared to the current standard procedure without creation of a flap. METHODS/DESIGN: PELYCAN is a parallel-group, patient- and assessor-blinded, phase III, adaptive randomized controlled superiority trial. Men with histologically confirmed prostate cancer who undergo transperitoneal RARP with pelvic LND will be randomly assigned in a 1:1 ratio to two groups-either with creating a peritoneal flap (PELYCAN) or without creating a peritoneal flap (control). Sample size calculation yielded a sample size of 300 with a planned interim analysis after 120 patients, which will be performed by an independent statistician. This provides a possibility for early stopping or sample size recalculation. Patients will be stratified for contributing factors for the development of postoperative lymphoceles. The primary outcome measure will be the rate of symptomatic lymphoceles in both groups within 6 months postoperatively. Patients and assessors will be blinded for the intervention until the end of the follow-up period of 6 months. The surgeon will be informed about the randomization result after performance of vesicourethral anastomosis. Secondary outcome measures include asymptomatic lymphoceles at the time of discharge and within 6 months of follow-up, postoperative complications, mortality, re-admission rate, and quality of life assessed by the EORTC QLQ-C30 questionnaire. DISCUSSION: The PELYCAN study is designed to assess whether the application of a peritoneal flap during RARP reduces the rate of symptomatic lymphoceles, as compared with the standard operation technique. In case of superiority of the intervention, this peritoneal flap may be suggested as a new standard of care. TRIAL REGISTRATION: German Clinical Trials Register DRKS00016794 . Registered on 14 May 2019.


Assuntos
Laparoscopia , Linfocele , Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Humanos , Laparoscopia/efeitos adversos , Excisão de Linfonodo/efeitos adversos , Linfocele/diagnóstico , Linfocele/etiologia , Linfocele/prevenção & controle , Masculino , Pelve , Prostatectomia/efeitos adversos , Neoplasias da Próstata/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Procedimentos Cirúrgicos Robóticos/efeitos adversos
9.
Science ; 168(3927): 129-30, 1970 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-5461364

RESUMO

A single injection of l-phenzylalanine in 7-day-old rats produtced disaggregation of brain polyribosomties and inhibition of in vitro protein synthesis in cell-free systems prepared from brain. Liver polyribosomes and in vitro protein synthesis in hepatic systems were not affected. In 4-week-old rats these effects on brain protein synthesis did not occur.


Assuntos
Química Encefálica , Fenilalanina/farmacologia , Fenilcetonúrias/metabolismo , Ribossomos/efeitos dos fármacos , Envelhecimento , Animais , Animais Recém-Nascidos , Sistema Livre de Células , Centrifugação com Gradiente de Concentração , Modelos Animais de Doenças , Humanos , Injeções Intraperitoneais , Biossíntese de Proteínas , Ratos
10.
Science ; 200(4339): 327-9, 1978 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-416494

RESUMO

A new antigenic determinant was discovered with a hemagglutination-inhibition assay system. Designated Hv(1), it is located in the variable region of human immunoglobulin heavy chains of the G, M, and A classes. Pedigree and population analyses suggest that it has an autosomal dominant mode of inheritance. This represents the first description of an allotypic determinant in the variable region of human immunoglobulins.


Assuntos
Sítios de Ligação de Anticorpos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina , Genes , Testes de Inibição da Hemaglutinação , Humanos , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/genética , Linhagem
11.
Cancer Res ; 51(7): 1783-8, 1991 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2004362

RESUMO

Intracellular glutathione (GSH) levels for seven mammalian cell lines (four human tumors, two rodent, one monkey) were determined by flow cytometry following staining with monochlorobimane (MBCl), and the results were compared with GSH levels measured by the Tietze assay. The mean fluorescence intensity for all but the two rodent lines did not correlate with GSH levels determined biochemically. Good agreement between the two assays was observed for the rodent lines following depletion of GSH by buthionine sulfoximine, but the level of GSH depletion achieved in the human and monkey lines was always underestimated by MBCl/flow cytometry. These discrepancies were not resolved by increasing stain concentration or staining time. Total glutathione S-transferase (GST) activity and GST isozyme profiles were determined for each of the cell lines. Western analysis with antibodies raised against rat Ya, Yb1, and Yc and human pi isozymes revealed that the rodent cell lines expressed abundant alpha (Ya, Yc subunits) and mu (Yb1 subunits) class isozymes. In contrast, GST-pi was the predominant isozyme detected in the human tumor cell lines and Cos-7 monkey cells. Michaelis-Menten analysis with purified GSTs from rat liver as well as purified human placental (pi) GST revealed that the conjugation of MBCl and GSH catalyzed by the alpha (1-1 and 2-2) and mu (3-3 and 3-4) class GST isozymes was approximately 10 and 80 times more efficient than was conjugation by the GST pi form, respectively. These data indicate that the GST-catalyzed conjugation of GSH and MBCl is isozyme dependent and that MBCl is a relatively poor substrate for the pi isozyme. As a consequence of this isozyme rate differential, the MBCl/flow cytometry technique for GSH quantitation must be applied cautiously, particularly with human tumor cells, many of which have been shown to have high GST-pi activity. Application to other cell types should also be made after careful characterization of GSH levels and GST isozyme composition and only after comparison with other independent assays of GSH concentration.


Assuntos
Citometria de Fluxo/métodos , Glutationa Transferase/análise , Glutationa/análise , Neoplasias/química , Pirazóis , Animais , Biomarcadores , Humanos , Células Tumorais Cultivadas/química
12.
Urologe A ; 55(4): 489-93, 2016 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-26646716

RESUMO

BACKGROUND: Infectious diseases caused by multi-resistant pathogens are increasing worldwide and are posing a challenge to German urology as well. Furthermore, there is a limited perspective of new antibiotic developments. One way out of this dilemma is a differentiated handling and use of antibiotics (antibiotic stewardship, ABS). AIM: The aim of this review is to identify key issues in modern urological antibiotic therapy, which can be considered as exemplary for the whole topic of ABS. This includes a review of the current data of the individual topics, including thought-provoking impulse for future clinical application and research. MATERIAL AND METHODS: The research group "infectious diseases" of GeSRU Academics identified the following central topics: excessive use of fluoroquinolones, diagnosis and treatment of urethritis and perioperative antibiotic prophylaxis. Subsequently, we performed a literature research in MEDLINE to uncover controversies and open questions of the individual topics within the meaning of ABS. RESULTS: The analysis of modern antibiotic therapy in urology shows numerous open questions in all quality dimensions of ABS: structural quality (e.g. through improved training of medical staff in the differentiated use of antibiotics), process quality (e.g. by improved adherence to existing infectiological guidelines, here in particular the perioperative prophylaxis and therapy of urethritis) and outcome (e.g. by detection of resistance rates and infection rates). DISCUSSION: The overarching and common goal is to avoid a post-antibiotic era. ABS programmes and a 10-point plan of the federal government are considered positive political developments in this area but do not release the individual urologist from a personal responsibility as part of his daily routine. A critical analysis of the topic "antibiotic treatment" is essential.


Assuntos
Antibacterianos/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/prevenção & controle , Padrões de Prática Médica/normas , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/prevenção & controle , Antibacterianos/efeitos adversos , Relação Dose-Resposta a Droga , Esquema de Medicação , Alemanha , Humanos
13.
Biochim Biophys Acta ; 405(1): 99-108, 1975 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-1174571

RESUMO

An acidic calcium-binding phosphoprotein has been isolated from a cholinergic tissue, electroplax from Electrophorus electricus. The purification procedures included (NH4)2SO4 fractionation, boiling treatment, ECTEOLA-cellulose chromatography, and gel filtration on Sephadex G-100. Experiments were performed to compare this protein and a calcium-binding protein isolated from mammalian brain, adrenal medulla, and testis. These experiments showed that the two proteins were identical in terms of molecular weight (14 000), calcium-binding dissociation constant (kd=2.1-10(-5) M), electrophoretic mobility at pH 8.7 in 15% polyacrylamide gels, and phosphorus content (1 mol phosphorus per mol protein). In addition, the two proteins had similar amino acid compositions and peptide maps. Although the electroplax protein was not present in eel skeletal muscle, preliminary experiments indicated that small amounts of the protein were present in other eel tissues, namely brain, liver and spleen. These results suggest an identity between the electroplax and mammalian calcium-binding proteins and extend the findind of comparatively large amounts of the protein from mammalian nervous tissue to a cholinergic nervous tissue, electroplax. The close similarity of the proteins suggests a conservation of structure during evolution which may be required to fulfill a role in neuronal function.


Assuntos
Cálcio/metabolismo , Órgão Elétrico/metabolismo , Proteínas do Tecido Nervoso/isolamento & purificação , Receptores de Droga , Aminoácidos/análise , Animais , Sítios de Ligação , Electrophorus , Cinética , Peso Molecular , Proteínas Musculares/análise , Proteínas do Tecido Nervoso/metabolismo , Especificidade de Órgãos , Fragmentos de Peptídeos/análise , Ligação Proteica , Especificidade da Espécie
14.
Biochim Biophys Acta ; 439(2): 316-25, 1976 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-182239

RESUMO

A soluble calcium-binding protein has been isolated from the red skeletal muscle of the electric eel (Electrophorus electricus). The purification procedure involved ammonium sulfate precipitation, gel filtration on Sephadex G-75 in the presence of 45Ca2+, and chromatography on QAE-Sephadex. This procedure resulted in the isolation of a protein which was homogeneous upon polyacrylamide gel electrophoresis. The calcium-binding protein was found to be a typical parvalbumin by the following criteria: (1) molecular weight of 11 000; (2) pI of 4.7; (3) 1.9 mol Ca2+ bound per mol protein; Kd of approx. 10(-7) M; (4) no detectable phosphorus; (5) amino acid composition included nine residues of phenylalanine, single arginine, and no tyrosine or tryptophan; (6) ximax at 259 nm; (7) 260 nm:280 nm absorbance ratio of 4.78. Only one parvalbumin could be detected in muscle. Immunoprecipitation assay revealed that the parvalbumin was a major soluble component of skeletal muscle (0.10 mg/mg soluble protein), but could not be detected in liver, kidney, brain, spleen, heart or electroplax. Comparison of the parvalbumin with a calcium-binding protein previously isolated from electroplax revealed that the two proteins were different as judged by a variety of chemical criteria. These results suggest that during embryological development of electroplax the parvalbumin is lost and that it is not required for the function of electric tissue.


Assuntos
Albuminas/metabolismo , Cálcio/metabolismo , Órgão Elétrico/metabolismo , Proteínas Musculares/metabolismo , Músculos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Aminoácidos/análise , Animais , Sítios de Ligação , Electrophorus , Ativação Enzimática , Imunodifusão , Cinética , Peso Molecular , Especificidade de Órgãos , Ligação Proteica
15.
Biochim Biophys Acta ; 801(2): 265-76, 1984 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-6089912

RESUMO

Dihomogammalinolenic acid (2.5-20 microM) added to suspensions of washed human platelets induces platelet shape change and the formation of 1,2-diacylglycerol and phosphatidic acid, indicating the activation of phospholipase C. It also stimulates the phosphorylation of a 40 kDa protein, indicating the activation of protein kinase C. Dihomogammalinolenic acid is converted mainly to 12-hydroxyheptadecadienoic acid and to a smaller extent to prostaglandin E1 and thromboxane B1. Small quantities of the lipoxygenase product 12-hydroxyeicosatrienoic acid are also observed. Indomethacin, by blocking platelet cyclooxygenase, prevents the activation of phospholipase C, protein kinase C, and platelet shape change induced by dihomogammalinolenic acid. Compound UK 38485, a specific thromboxane synthetase inhibitor, does not block platelet activation induced by dihomogammalinolenic acid. The results indicate that endoperoxides derived from dihomogammalinolenic acid, such as prostaglandin G1 or prostaglandin H1, may be responsible for the stimulation of phospholipase C and protein kinase C, and for the induction of platelet shape change. Eicosapentaenoic acid does not activate platelets and is poorly metabolized by platelet cyclooxygenase and lipoxygenase. Eicosapentaenoic acid is a better inhibitor of platelet activation induced by various agonists in washed platelets than dihomogammalinolenic acid. Eicosapentaenoic acid and dihomogammalinolenic acid are, however, equally effective in inhibiting aggregation induced by collagen in platelet-rich plasma. We suggest that eicosapentaenoic acid might be a better antithrombotic agent than dihomogammalinolenic acid.


Assuntos
Ácido 8,11,14-Eicosatrienoico/farmacologia , Ácidos Graxos Insaturados/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Plaquetas/fisiologia , Plaquetas/ultraestrutura , Ácido Eicosapentaenoico , Ativação Enzimática , Humanos , Microscopia Eletrônica de Varredura , Fosfolipases Tipo C/sangue
16.
Biochim Biophys Acta ; 1079(2): 174-81, 1991 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-1911840

RESUMO

A proteinase specific for calmodulin has been identified in a crude rat kidney Triton-extracted or sonicated mitochondrial fraction and solubilized by EGTA extraction of these membranes. Mitochondrial fractions from other tissues had less activity, with relative activities: kidney = spleen greater than testes greater than liver, and no detectable activity in either brain or skeletal muscle. This enzyme is active in the presence of EGTA, but not in the presence of calcium, and cleaves calmodulin into three major peptide fragments with Mr 6000, 9000 and 10,000. N-methylated and non-methylated calmodulins were both cleaved by calmodulin proteinase and while troponin was a poor substrate, it was cleaved in the presence of either calcium or EGTA. No other EF hand calcium-binding proteins or other major mitochondrial proteins were cleaved by this enzyme. The peptides resulting from calmodulin proteinase action were isolated by reverse-phase high performance liquid chromatography (HPLC) and sequenced. Sequence analysis indicated that calmodulin proteinase cleaves calmodulin at Lys-75. The effects of proteinase inhibitors indicate that calmodulin proteinase is a trypsin-like enzyme belonging to the serine endopeptidase family of enzymes.


Assuntos
Calmodulina/isolamento & purificação , Endopeptidases/isolamento & purificação , Membranas Intracelulares/enzimologia , Rim/enzimologia , Mitocôndrias/enzimologia , Serina Endopeptidases , Sequência de Aminoácidos , Animais , Cálcio , Cátions , Cromatografia Líquida de Alta Pressão , Ácido Egtázico , Eletroforese em Gel de Poliacrilamida , Endopeptidases/metabolismo , Histonas/metabolismo , Concentração de Íons de Hidrogênio , Oxirredutases N-Desmetilantes/metabolismo , Peptídeos/isolamento & purificação , Ratos , Especificidade por Substrato , Troponina/metabolismo
17.
World J Gastroenterol ; 11(40): 6366-72, 2005 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-16419167

RESUMO

AIM: To establish the most common vacA alleles in Helicobacter pylori (H pylori) strains isolated from Chilean patients and its relationship with gastritis and gastroduodenal ulcers. METHODS: Two hundred and forty five H pylori clinical isolates were obtained from 79 biopsies from Chilean infected patients suffering from gastrointestinal diseases. An average of 2-3 strains per patient was isolated and the vacA genotype was analyzed by PCR and 3% agarose electrophoresis. Some genotypes were checked by DNA sequencing. RESULTS: The most prevalent vacA genotype in Chilean patients was s1b m1 (76%), followed by s1a m1 (21%). In contrast, the s2 m2 genotype was scarcely represented (3%). The s1b m1 genotype was found most frequently linked to gastropathies (P<0.05) rather than ulcers. Ulcers were found more commonly in male and older patients. Curiously, patients living in cities located North and far South of Santiago, the capital and largest Chilean city, carried almost exclusively strains with the s1b m1 genotype. In contrast, patients from Santiago and cities located South of Santiago carried strains with either one or both s1a m1 and s1b m1 genotypes. Regarding the s2 m2 genotype, comparison with GenBank sequences revealed that Chilean s2 sequence was identical to those of Australian, American, and Colombian strains but quite different from those of Alaska and India. CONCLUSION: Differences in geographic distribution of the s and m vacA alleles in Chile and a relationship of s1b m1 genotype with gastritis were found. Sequence data in part support a hispanic origin for the vacA genotype. Asymmetric distribution of genotypes s1b m1 and s2 m2 recedes H Pylori strain distribution in Spain and Portugal.


Assuntos
Alelos , Proteínas de Bactérias/genética , Gastroenteropatias/microbiologia , Helicobacter pylori/genética , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Criança , Pré-Escolar , Chile , Feminino , Infecções por Helicobacter , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Alinhamento de Sequência
18.
Endocrinology ; 142(3): 1017-23, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11181514

RESUMO

Currently, no effective therapy exists for patients suffering from progressive medullary thyroid carcinoma (MTC), a calcitonin (CT)-secreting C cell tumor. As CT, which arises from the precursor protein preprocalcitonin (PPCT), is expressed by almost all MTC cases, these molecules may represent target antigens for immunotherapy against MTC. In our study we investigated whether DNA immunization is able to induce cellular and humoral immune responses against human PPCT (hPPCT) in mice. Antigen-encoding expression plasmids were delivered intradermally by gene gun. One group of mice received DNA encoding hPPCT only. Two groups were coinjected with mouse cytokine genes. We observed in lymphocyte proliferative assays substantial proliferation against hPPCT in mice coinjected with the granulocyte-macrophage colony-stimulating factor (GM-CSF) gene, in contrast to mice vaccinated with hPPCT expression plasmid only. In addition, codelivery of the GM-CSF gene augmented the frequency of anti-hPPCT antibody seroconversions in sera of immunized animals, as shown by enzyme-linked immunosorbent assay. These results illustrate that cellular and humoral immune responses against hPPCT can be generated by DNA immunization and increased by coinjection of the GM-CSF gene. Our findings may have implications for the use of DNA immunization as a potential novel immunotherapeutic treatment for patients suffering from progressive MTC.


Assuntos
Calcitonina/imunologia , Carcinoma Medular/terapia , Técnicas Genéticas , Imunização/métodos , Precursores de Proteínas/imunologia , Neoplasias da Glândula Tireoide/terapia , Animais , Formação de Anticorpos , Calcitonina/genética , Calcitonina/farmacologia , Divisão Celular/efeitos dos fármacos , Feminino , Expressão Gênica , Humanos , Imunidade Celular , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos/genética , Precursores de Proteínas/genética , Precursores de Proteínas/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Linfócitos T/citologia
19.
Endocrinology ; 116(3): 1051-9, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3918845

RESUMO

We investigated the role of cellular calcium pools in angiotensin II-stimulated aldosterone synthesis in bovine adrenal glomerulosa cells. Angiotensin II decreased the size of the exchangeable cell calcium pool by 34%, consistent with previous observations that angiotensin II causes decreased uptake of 45Ca+2 into cells and increased efflux of 45Ca+2 from preloaded cells. Atomic absorption spectroscopy showed that angiotension II caused a decrease of 21% in total cellular calcium. Angiotensin II caused efflux of 45Ca+2 in the presence of EGTA and retarded uptake of 45Ca+2 when choline was substituted for sodium, suggesting that hormone effects on calcium pools do not involve influx of trigger calcium or sodium. Cells incubated in calcium-free buffer and 0.1 mM or 0.5 mM EGTA synthesized reduced (but still significant) amounts of the steroid in response to hormone. Cells incubated in increasing concentrations of extracellular calcium contained increasing amounts of intracellular calcium and synthesized increasing amounts of aldosterone in response to angiotensin II. These results point to the participation of intracellular calcium pools in angiotensin II-stimulated steroidogenesis and the importance of extracellular calcium in maintaining these pools.


Assuntos
Glândulas Suprarrenais/metabolismo , Aldosterona/biossíntese , Angiotensina II/farmacologia , Cálcio/metabolismo , Glândulas Suprarrenais/citologia , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Radioisótopos de Cálcio , Bovinos , Ácido Egtázico/farmacologia , Feminino , Sódio/farmacologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-1375290

RESUMO

To allow the precise definition of the anti-lentiviral immune response in the natural host and to facilitate the development of an alternative animal model for vaccine development, we are identifying the immunogenic domains of SIVagm proteins. First, a total of 173 synthetic 15-mer peptides with an overlap of 10 amino acids were produced spanning the entire envelope glycoprotein of the molecular clone SIVagm3. These peptides were used as antigen in enzyme-linked immunosorbent assays for identifying regions recognized by antibodies from naturally infected African green monkeys and monkeys infected with a molecular clone. Regions corresponding to the HIV-1 V3, the transmembrane protein (TMP) "Gnann peptide", and the C-terminal area of the outer envelope protein were shown to be immunodominant. These regions were re-synthesized as 15-mer peptides with an overlap of 14 amino acids and used to precisely map the epitopes recognized. Sera from 93 captive and 61 wild animals were tested by SIVagm-specific Western blot (WB) and for ELISA reactivity against the immunodominant TMP peptide. One hundred percent (76/76) of the WB-positive captive animals and 98% (41/42) wild WB-positive animals also reacted against the peptide. In contrast, only 62% of the WB-positive sera reacted with the "V3" epitope and 46% with the gp130 C-terminal epitope.


Assuntos
Linfócitos B/imunologia , Epitopos/imunologia , Glicoproteínas de Membrana/imunologia , Vírus da Imunodeficiência Símia/imunologia , Proteínas do Envelope Viral/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Chlorocebus aethiops , Epitopos Imunodominantes/imunologia , Macaca nemestrina , Dados de Sequência Molecular
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