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1.
Ann Surg Oncol ; 30(13): 8244-8250, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37782412

RESUMO

BACKGROUND: Studies have shown minimally invasive esophagectomy (MIE) to be a feasible surgical technique in treating esophageal carcinoma. Postoperative complications have been extensively reviewed, but literature focusing on intraoperative complications is limited. The main objective of this study was to report major intraoperative complications and 90-day mortality during MIE for cancer. METHODS: Data were collected retrospectively from 10 European esophageal surgery centers. All intention-to-treat, minimally invasive laparoscopic/thoracoscopic esophagectomies with gastric conduit reconstruction for esophageal and GE junction cancers operated on between 2003 and 2019 were reviewed. Major intraoperative complications were defined as loss of conduit, erroneous transection of vascular structures, significant injury to other organs including bowel, heart, liver or lung, splenectomy, or other major complications including intubation injuries, arrhythmia, pulmonary embolism, and myocardial infarction. RESULTS: Amongst 2862 MIE cases we identified 98 patients with 101 intraoperative complications. Vascular injuries were the most prevalent, 41 during laparoscopy and 19 during thoracoscopy, with injuries to 18 different vessels. There were 24 splenic vascular or capsular injuries, 11 requiring splenectomies. Four losses of conduit due to gastroepiploic artery injury and six bowel injuries were reported. Eight tracheobronchial lesions needed repair, and 11 patients had significant lung parenchyma injuries. There were 2 on-table deaths. Ninety-day mortality was 9.2%. CONCLUSIONS: This study offers an overview of the range of different intraoperative complications during minimally invasive esophagectomy. Mortality, especially from intrathoracic vascular injuries, appears significant.


Assuntos
Neoplasias Esofágicas , Laparoscopia , Lesões do Sistema Vascular , Humanos , Esofagectomia/efeitos adversos , Estudos Retrospectivos , Lesões do Sistema Vascular/complicações , Lesões do Sistema Vascular/cirurgia , Neoplasias Esofágicas/cirurgia , Complicações Intraoperatórias/etiologia , Complicações Pós-Operatórias/etiologia , Toracoscopia/métodos , Laparoscopia/métodos , Resultado do Tratamento , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos
2.
Dis Esophagus ; 34(6)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-32960264

RESUMO

There are no internationally recognized criteria available to determine preparedness for hospital discharge after esophagectomy. This study aims to achieve international consensus using Delphi methodology. The expert panel consisted of 40 esophageal surgeons spanning 16 countries and 4 continents. During a 3-round, web-based Delphi process, experts voted for discharge criteria using 5-point Likert scales. Data were analyzed using descriptive statistics. Consensus was reached if agreement was ≥75% in round 3. Consensus was achieved for the following basic criteria: nutritional requirements are met by oral intake of at least liquids with optional supplementary nutrition via jejunal feeding tube. The patient should have passed flatus and does not require oxygen during mobilization or at rest. Central venous catheters should be removed. Adequate analgesia at rest and during mobilization is achieved using both oral opioid and non-opioid analgesics. All vital signs should be normal unless abnormal preoperatively. Inflammatory parameters should be trending down and close to normal (leucocyte count ≤12G/l and C-reactive protein ≤80 mg/dl). This multinational Delphi survey represents the first expert-led process for consensus criteria to determine 'fit-for-discharge' status after esophagectomy. Results of this Delphi survey may be applied to clinical outcomes research as an objective measure of short-term recovery. Furthermore, standardized endpoints identified through this process may be used in clinical practice to guide decisions regarding patient discharge and may help to reduce the risk of premature discharge or prolonged admission.


Assuntos
Esofagectomia , Alta do Paciente , Consenso , Técnica Delphi , Humanos , Inquéritos e Questionários
3.
Dis Esophagus ; 32(7)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30596963

RESUMO

Endoluminal vacuum therapy (EVT) is an accepted treatment for anastomotic leakage (AL) after esophagectomy. A novel concept is to use this technology in a preemptive setting, with the aim to reduce the AL rate and postoperative morbidity. Preemptive EVT (pEVT) was performed intraoperatively in 19 consecutive patients undergoing minimally invasive esophagectomy, immediately after completion of esophagogastrostomy. Twelve patients (63%) were high-risk cases with severe comorbidity. The EVT device was removed routinely three to six (median 5) days after esophagectomy. The endpoints of this study were AL rate and postoperative morbidity. There were 20 anastomoses at risk in 19 patients. One patient (5.3%) experienced major morbidity (Clavien-Dindo grade IIIb) unrelated to anastomotic healing. He underwent open reanastomosis at postoperative day 12 with pEVT for redundancy of the gastric tube and failure of transition to oral diet. Mortality after 30 days was 0% and anastomotic healing was uneventful in 19/20 anastomoses (95%). One minor contained AL healed after a second course of EVT. Except early proximal dislodgement in one patient, there were no adverse events attributable to pEVT. The median comprehensive complication index 30 days after surgery was 20.9 (IQR 0-26.2). PEVT appears to be a safe procedure that may have the potential to improve surgical outcome in patients undergoing esophagectomy.


Assuntos
Fístula Anastomótica/prevenção & controle , Esofagectomia/efeitos adversos , Idoso , Fístula Anastomótica/etiologia , Esofagectomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tampões de Gaze Cirúrgicos , Vácuo , Cicatrização
5.
Eur Radiol ; 28(6): 2700-2707, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29372312

RESUMO

OBJECTIVES: To assess the additional diagnostic value of 18F-fluorocholine PET imaging in preoperative localization of pathologic parathyroid glands in clinically manifest hyperparathyroidism in case of negative or conflicting ultrasound and scintigraphy results. METHODS: A retrospective, single-institution study of 26 patients diagnosed with hyperparathyroidism. In cases where ultrasound and scintigraphy failed to detect the location of an adenoma in order to allow a focused surgical approach, an additional 18F-fluorocholine PET scan was performed and its results were compared with the intraoperative findings. RESULTS: A total of 26 patients underwent 18F-fluorocholine PET/CT (n = 11) or PET/MRI (n = 15). Adenomas were detected in 25 patients (96.2%). All patients underwent surgery, and the location predicted by PET hybrid imaging was confirmed intraoperatively by frozen section and adequate parathyroid hormone drop after removal. None of the patients needed revision surgery during follow-up. CONCLUSIONS: These results demonstrate that 18F-fluorocholine PET imaging is a highly accurate method to detect parathyroid adenomas even in case of previous localization failure by other imaging examinations. KEY POINTS: • With 18 F-fluorocholine PET imaging, parathyroid adenomas could be detected in 96.2%. • 18 F-fluorocholine imaging is a highly accurate method to detect parathyroid adenomas. • We encourage its use, where ultrasound fails to detect an adenoma.


Assuntos
Adenoma/diagnóstico por imagem , Colina/análogos & derivados , Hiperparatireoidismo Primário/diagnóstico por imagem , Neoplasias das Paratireoides/diagnóstico por imagem , Compostos Radiofarmacêuticos , Adenoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Radioisótopos de Flúor , Humanos , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Glândulas Paratireoides/diagnóstico por imagem , Neoplasias das Paratireoides/cirurgia , Exame Físico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Cintilografia , Reoperação , Estudos Retrospectivos , Ultrassonografia
6.
Am J Transplant ; 17(7): 1879-1884, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28024112

RESUMO

Living kidney donation is safe and established, but can lead to long-term complications such as chronic fatigue. Since the adrenal vein is usually transected during left-sided donor nephrectomy-which is not necessary on the right-we hypothesized that venous congestion might lead to an impairment of adrenal function, offering a possible explanation. In this prospective open label, monocentric cohort study, adrenal function was compared in left- and right-sided living kidney donors. The primary endpoint was plasma cortisol response to low-dose adrenocorticotropic hormone (ACTH) stimulation. Secondary endpoints included plasma renin and ACTH concentration as well as adrenal volume in response to donor nephrectomy. A total of 30 healthy donors-20 left- and 10 right-sided donations-were included. On postoperative day 1, response to low-dose ACTH stimulation was intact, but significantly lower after left-sided donor nephrectomy. After 28 days, adrenal responsiveness to ACTH stimulation did not differ any longer. Magnetic resonance imaging volumetry showed no significant adrenal volume change over 4 weeks, neither after left- nor after right-sided nephrectomy. In conclusion, left-sided living kidney donation entails a transiently reduced adrenocortical responsiveness, which returns to baseline after 28 days.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Hidrocortisona/metabolismo , Transplante de Rim/métodos , Rim/metabolismo , Laparoscopia/métodos , Doadores Vivos , Coleta de Tecidos e Órgãos/métodos , Feminino , Seguimentos , Taxa de Filtração Glomerular , Hormônios/farmacologia , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Nefrectomia , Prognóstico , Estudos Prospectivos
7.
Colorectal Dis ; 17(7): 619-26, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25641401

RESUMO

AIM: The study aimed to compare the rate of success and cost of anal fistula plug (AFP) insertion and endorectal advancement flap (ERAF) for anal fistula. METHOD: Patients receiving an AFP or ERAF for a complex single fistula tract, defined as involving more than a third of the longitudinal length of of the anal sphincter, were registered in a prospective database. A regression analysis was performed of factors predicting recurrence and contributing to cost. RESULTS: Seventy-one patients (AFP 31, ERAF 40) were analysed. Twelve (39%) recurrences occurred in the AFP and 17 (43%) in the ERAF group (P = 1.00). The median length of stay was 1.23 and 2.0 days (P < 0.001), respectively, and the mean cost of treatment was €5439 ± €2629 and €7957 ± €5905 (P = 0.021), respectively. On multivariable analysis, postoperative complications, underlying inflammatory bowel disease and fistula recurring after previous treatment were independent predictors of de novo recurrence. It also showed that length of hospital stay ≤ 1 day to be the most significant independent contributor to lower cost (P = 0.023). CONCLUSION: Anal fistula plug and ERAF were equally effective in treating fistula-in-ano, but AFP has a mean cost saving of €2518 per procedure compared with ERAF. The higher cost for ERAF is due to a longer median length of stay.


Assuntos
Proctoscopia/economia , Fístula Retal/cirurgia , Retalhos Cirúrgicos , Instrumentos Cirúrgicos , Adulto , Custos e Análise de Custo , Bases de Dados Factuais , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Proctoscopia/instrumentação , Proctoscopia/métodos , Estudos Prospectivos , Fístula Retal/economia , Fístula Retal/patologia , Reto/cirurgia , Recidiva , Estudos Retrospectivos , Retalhos Cirúrgicos/economia , Instrumentos Cirúrgicos/economia , Resultado do Tratamento
8.
HNO ; 59(10): 988-93, 2011 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-21181390

RESUMO

Approximately 25% of the population in industrialized countries suffer from IgE-associated Type-1 allergies. Multiple allergens can be tested simultaneously in one assay by using the protein microarray. Moreover, it is possible to measure more than one analytical parameter (e.g. allergen specific IgEs and IgGs) in one assay by combining different fluorescent markers with specific secondary antibodies. The different allergen components that are of interest are immobilized on a planar surface. By adding the patient's serum (a smaller amount of serum is needed compared to an immunoassay) the inherent IgE antibodies are captured by the corresponding allergens. Secondary fluorescing anti-IgE antibodies are added subsequently, thus the intensity of each spot on the microarray can be measured by using a biochipscanner. The detected signal is then transformed into quantitative data, which allows the classification of the patient's serum IgE level for the tested allergens. There are different approaches to reduce the complexity of the original extracts used for the production of the solid microarray phase to a smaller number of relevant pathogenic molecules. The component-resolved diagnosis still needs to be clinically validated, but initial studies show positive results concerning the sensitivity and specificity of the protein microarray. Protein microarrays are promising tools for screening diagnoses in allergic diseases as well as for the improvement of allergen-specific immunotherapy.


Assuntos
Alérgenos/imunologia , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/sangue , Análise Serial de Proteínas/métodos , Especificidade de Anticorpos/imunologia , Epitopos/imunologia , Humanos , Valor Preditivo dos Testes
9.
Hear Res ; 381: 107780, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31437651

RESUMO

A robust temporary threshold shift (TTS) can create significant primary damage to the auditory synapse, termed cochlear synaptopathy (CS). The common model applied to examination of this pathology is a single noise exposure or extended duration exposures at relatively high noise dosages. It is unclear if a single noise exposure that does not produce physiological changes consistent with CS (such as suppressed suprathreshold responses) can create evidence consistent with the pathology induced by repeated exposures. Here, we exposed 16-week (wk) old Sprague-Dawley rats to repeated noise exposures (4 consecutive days, 8-16 kHz octave-band of noise, 97 dB SPL for 2 h) and examined measures of cochlear function (distortion product otoacoustic emissions) and auditory neural integrity (auditory brainstem response, wave 1 amplitude). Our results demonstrated a mean maximal threshold shift of 16 dB at 24 h post the initial noise exposure. Subsequent daily repeated exposures (4 consecutive days) resulted in diminished threshold shift at 24 h post repeated TTS. In addition to recovered thresholds, no sustained reduction in suprathreshold responses was observed. The findings are consistent with conditioning literature suggesting diminished TTS with repeated exposures. Repeated TTS that was not individually synaptopathic did not produce physiological evidence consistent with acute CS.


Assuntos
Fadiga Auditiva , Vias Auditivas/fisiologia , Cóclea/fisiologia , Audição , Ruído/efeitos adversos , Estimulação Acústica , Animais , Potenciais Evocados Auditivos do Tronco Encefálico , Feminino , Masculino , Emissões Otoacústicas Espontâneas , Ratos Sprague-Dawley , Fatores de Tempo
10.
Neuron ; 17(6): 1251-64, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8982171

RESUMO

The isk gene is expressed in many tissues. Pharmacological evidence from the inner ear suggests that isk mediates potassium secretion into the endolymph. To examine the consequences of IsK null mutation on inner ear function, and to produce a system useful for examining the role(s) IsK plays elsewhere, we have produced a mouse strain that carries a disrupted isk locus. Knockout mice exhibit classic shaker/waltzer behavior. Hair cells degenerate, but those of different inner ear organs degenerate at different times. Functionally, we show that in mice lacking isk, the strial marginal cells and the vestibular dark cells of the inner ear are unable to generate an equivalent short circuit current in vitro, indicating a lack of transepithelial potassium secretion.


Assuntos
Orelha Interna/anormalidades , Genes , Mutação , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/genética , Animais , Comportamento Animal , Contagem de Células , Morte Celular , Cóclea/anormalidades , Cóclea/patologia , Orelha Interna/metabolismo , Orelha Interna/patologia , Células Ciliadas Auditivas/fisiologia , Camundongos , Potássio/metabolismo
11.
Neuron ; 23(1): 93-103, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10402196

RESUMO

Cochlear outer hair cells (OHCs) express alpha9 nACh receptors and are contacted by descending, predominately cholinergic, efferent fibers originating in the CNS. Mice carrying a null mutation for the nACh alpha9 gene were produced to investigate its role(s) in auditory processing and development of hair cell innervation. In alpha9 knockout mice, most OHCs were innervated by one large terminal instead of multiple smaller terminals as in wild types, suggesting a role for the nACh alpha9 subunit in development of mature synaptic connections. Alpha9 knockout mice also failed to show suppression of cochlear responses (compound action potentials, distortion product otoacoustic emissions) during efferent fiber activation, demonstrating the key role alpha9 receptors play in mediating the only known effects of the olivocochlear system.


Assuntos
Cóclea/inervação , Receptores Nicotínicos/fisiologia , Animais , Cóclea/citologia , Cóclea/fisiologia , Vias Eferentes/crescimento & desenvolvimento , Vias Eferentes/fisiologia , Células Ciliadas Auditivas Externas/fisiologia , Camundongos , Camundongos Knockout/genética , Núcleo Olivar/fisiologia , Receptores Nicotínicos/genética
12.
Eur J Cancer ; 44(4): 528-38, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18242076

RESUMO

The FFCD 9402 multicentre phase III trial was designed to compare the effects of the combination of Transarterial Lipiodol Chemoembolisation (TACE) and tamoxifen with tamoxifen alone on overall survival and quality of life in the palliative treatment of hepatocellular carcinoma with cirrhosis. From 1995 to 2002, 138 patients were randomised between the two groups. One hundred and twenty three patients were eligible including 61 in the Tamoxifen group and 62 in the TACE group. Baseline characteristics were similar: Child-Pugh class A: 70%, alcoholic cirrhosis: 76%, Okuda stage I: 71%, multinodular tumour: 70% and segmental portal vein thrombosis: 10%. At 2years, the overall survival was 22% and 25% in the Tamoxifen and TACE groups (P=.68), respectively. Multivariate analysis identified four independent prognostic factors for survival: alpha-fetoprotein (AFP)>400ng/mL (P=.008), abdominal pain (P=.011), hepatomegaly (P=.023) and Child-Pugh score (P=.032). The Spitzer Index level assessing the quality of life during follow-up did not differ between the two groups (P=.70). Amongst patients with stage Okuda I, the 2-year overall survival was 28% in the Tamoxifen group and 32% in the TACE group (P=.58). In this subgroup, two prognostic factors were statistically significant for survival: AFP>400ng/mL (P=.004) and Spitzer Index (P=.013) as shown by multivariable analysis. In conclusion, this study suggests that TACE improves neither the survival nor the quality of life in patients with HCC and cirrhosis.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas/terapia , Tamoxifeno/uso terapêutico , Carcinoma Hepatocelular/complicações , Terapia Combinada , Feminino , Humanos , Infusões Intra-Arteriais , Tempo de Internação , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Análise de Sobrevida , Resultado do Tratamento
13.
Rev Laryngol Otol Rhinol (Bord) ; 129(2): 85-90, 2008.
Artigo em Francês | MEDLINE | ID: mdl-18767325

RESUMO

OBJECTIVE: This study aimed at evaluating the performance of Cine-MRI to assess swallowing in patients previously treated for head and neck cancer. MATERIALS AND METHODS: 10 healthy control subjects and a cohort of 10 patients with 8 partial glossectomies, 1 total laryngectomy and 1 glossolaryngectomy underwent imaging from October 2005 to February 2007. The MRI examinations were performed on a 1.5 Tesla system (Siemens Avanto), with True-Fisp sequences (TR = 170 ms, TE = 1 ms, slice thickness = 10 mm) at a rate of 8 pictures per second, during dry swallowing. RESULTS: Results are relevant for real-time spatial resolution from lips to larynx and dynamic motions analyses of tongue, velum, posterior pharyngeal wall and larynx during dry swallowing. Oro-pharyngo-laryngeal occlusion deficiency induces aspiration in case of partial glossectomy. Total laryngectomy modifies tongue, velum and pharynx landmarks. CONCLUSION: Cine-MRI i) provides functional insight from the oral cavity to the larynx, ii) gives accurate informations about impairments due to the pathology and its treatment, iii) completes others investigations like fiberoptic endoscopy or transit time, iiii) allows a precise analysis of the muscular movements involved in the deficient swallowing mechanism, in order to optimize rehabilitative strategies and results.


Assuntos
Cinerradiografia , Transtornos de Deglutição/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/reabilitação , Feminino , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Laringectomia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Índice de Gravidade de Doença
14.
Circulation ; 102(15): 1814-21, 2000 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11023937

RESUMO

BACKGROUND: In adult human heart, both beta(1)- and beta(2)-adrenergic receptors mediate hastening of relaxation; however, it is unknown whether this also occurs in infant heart. We compared the effects of stimulation of beta(1)- and beta(2)-adrenergic receptors on relaxation and phosphorylation of phospholamban and troponin I in ventricle obtained from infants with tetralogy of Fallot. METHODS AND RESULTS: Myocardium dissected from the right ventricular outflow tract of 27 infants (age range 21/2 to 35 months) with tetralogy of Fallot was set up to contract 60 times per minute. Selective stimulation of beta(1)-adrenergic receptors with (-)-norepinephrine (NE) and beta(2)-adrenergic receptors with (-)-epinephrine (EPI) evoked phosphorylation of phospholamban (at serine-16 and threonine-17) and troponin I and caused concentration-dependent increases in contractile force (-log EC(50) [mol/L] NE 5.5+/-0.1, n=12; EPI 5.6+/-0.1, n=13 patients), hastening of the time to reach peak force (-log EC(50) [mol/L] NE 5.8+/-0.2; EPI 5.8+/-0.2) and 50% relaxation (-log EC(50) [mol/L] NE 5.7+/-0.2; EPI 5.8+/-0.1). Ventricular membranes from Fallot infants, labeled with (-)-[(125)I]-cyanopindolol, revealed a greater percentage of beta(1)- (71%) than beta(2)-adrenergic receptors (29%). Binding of (-)-epinephrine to beta(2)-receptors underwent greater GTP shifts than binding of (-)-norepinephrine to beta(1)-receptors. CONCLUSIONS: Despite their low density, beta(2)-adrenergic receptors are nearly as effective as beta(1)-adrenergic receptors of infant Fallot ventricle in enhancing contraction, relaxation, and phosphorylation of phospholamban and troponin I, consistent with selective coupling to G(s)-protein.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Miocárdio/metabolismo , Receptores Adrenérgicos beta 1/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Tetralogia de Fallot/metabolismo , Troponina I/metabolismo , Pré-Escolar , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Epinefrina/metabolismo , Feminino , Guanosina Trifosfato/metabolismo , Ventrículos do Coração/citologia , Ventrículos do Coração/fisiopatologia , Humanos , Lactente , Masculino , Contração Miocárdica , Miocárdio/patologia , Fosforilação , Serina/metabolismo , Treonina/metabolismo
15.
Neuropharmacology ; 39(13): 2525-32, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11044724

RESUMO

In the present study, we report that the alpha9 nicotinic acetylcholine receptor (nAChR) expressed in Xenopus laevis oocytes is reversibly blocked by aminoglycoside antibiotics. The aminoglycosides tested blocked the alpha9 nAChR in a concentration-dependent manner with the following rank order of potency: neomycin>gentamicin>streptomycin>amikacin>kanamycin. The antagonistic effect of gentamicin was not overcome by increasing the concentration of acetylcholine (ACh), indicative of a non-competitive type of block. Blockage of ACh-evoked currents by gentamicin was found to be voltage-dependent, being more potent at hyperpolarized than at depolarized holding potentials. Furthermore, gentamicin blockage was dependent upon the extracellular Ca(2+) concentration, shown by the fact that increments in extracellular Ca(2+) significantly reduced the potency of this aminoglycoside to block the alpha9 nAChR. Possible mechanisms of blockage by the aminoglycosides are discussed. The present results suggest that the initial reversible actions of aminoglycosides at the organ of Corti, such as the elimination of the olivocochlear efferent function, are due in part to the interaction with the native alpha9-containing cholinergic receptor of the outer hair cells.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/toxicidade , Transtornos da Audição/induzido quimicamente , Antagonistas Nicotínicos/farmacologia , Receptores Nicotínicos/metabolismo , Animais , Cálcio/metabolismo , Quelantes/farmacologia , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Estimulação Elétrica , Eletrofisiologia , Gentamicinas/farmacologia , Gentamicinas/toxicidade , Núcleo Olivar/efeitos dos fármacos , Oócitos/metabolismo , Ratos , Xenopus
16.
J Neurosci Methods ; 97(1): 59-67, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10771076

RESUMO

This report summarizes positive reinforcement conditioning procedures for assessing sensory function in transgenic mice. To illustrate these behavioral methods auditory sensitivity was measured in mice lacking alpha9 acetylcholine receptor subunits (alpha9 knock-out mice). These receptors are known to play an important role in the efferent pathways that modify cochlear responses to sound stimuli. The strategies of parameter manipulation that led these subjects through their preliminary training stages to stable threshold performances are described in detail. Techniques for estimating and interpreting sensory thresholds are discussed from the perspective of signal detection analyses. This study found no significant differences between alpha9 knock-out mice and control subjects when hearing thresholds were measured under quiet conditions, as predicted by previous behavioral and electrophysiological evidence.


Assuntos
Limiar Auditivo/fisiologia , Comportamento Animal/fisiologia , Audição/genética , Audição/fisiologia , Estimulação Acústica , Animais , Condicionamento Operante/fisiologia , Comportamento Exploratório/fisiologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Receptores Colinérgicos/efeitos dos fármacos , Receptores Colinérgicos/genética , Software
17.
Arch Dermatol ; 131(7): 801-4, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7611796

RESUMO

BACKGROUND AND DESIGN: The role of hepatitis C virus (HCV) infection in porphyria cutanea tarda (PCT) is probable since the global HCV antibody prevalence among patients with PCT is about 70%. The purpose of this study was to evaluate the virologic characteristics in 12 patients with sporadic PCT and in one patient with familial PCT. Anti-HCV antibodies were detected by enzyme-linked immunosorbent assay and confirmed by recombinant immunoblot assay. Hepatitis B virus and antihuman immunodeficiency virus markers were also determined. The polymerase chain reaction was performed to detect the following: (1) both positive and negative HCV RNA strands, (2) HCV RNA titer, and (3) HCV RNA genotype. RESULTS: Seven of the 12 patients with sporadic PCT were HCV positive, and the patient with familial PCT was HCV negative. The age at onset of PCT was significantly lower in HCV-positive patients than in HCV-negative patients. The HCV RNA was detected in all patients who had HCV antibodies, and the replicative intermediate of HCV was detected in three of them. The positive RNA titer ranged from 1:10 to 1:10(6). Four patients were infected by HCV genotype I, two by genotype II, and one patient was coinfected by type I and type II. Three of the seven HCV-positive patients also had HBV antibodies, but HBV DNA was never detected. All patients were negative for the human immunodeficiency virus. CONCLUSIONS: The HCV infection rate was high (58%) in this series, and all HCV-infected patients had HCV RNA, reflecting an active replication of the virus. The young age at onset of PCT suggests that HCV is a major triggering factor of PCT. Nevertheless, the clinical changes of PCT were not related to the virologic findings, suggesting an indirect role of HCV.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/complicações , Porfiria Cutânea Tardia/virologia , Adulto , Idoso , Feminino , Hepacivirus/imunologia , Anticorpos Anti-Hepatite/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Porfiria Cutânea Tardia/sangue
18.
Arch Dermatol ; 132(12): 1448-52, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8961873

RESUMO

OBJECTIVE: Many cases of porphyria cutanea tarda have been described in association with human immunodeficiency virus (HIV) infection in young individuals. The link between hepatitis C virus (HCV) and porphyria cutanea tarda is even stronger as more than 50% of patients who have this diagnosis in Italy, France, or Spain are also infected by HCV. To study the role of viral infections on the metabolism of porphyrins, we measured the urinary porphyrin levels in patients with HIV and HCV infections. DESIGN: Survey; prospective study. SETTING: University Hospital of Strasbourg, France. PATIENTS: Sixty-one HIV-positive patients, 56 HCV-positive patients, 60 HIV- and HCV-positive patients, and 51 HIV- and HCV-negative control subjects were randomly selected. None had clinical signs of porphyria or a familial history of porphyria. MAIN OUTCOME MEASURES: The porphyrin-excretion profile was determined by high-performance liquid chromatography on fresh urine samples. The HIV and HCV viremias were quantified in the serum by the branched DNA assay. Measures were planned before data collection began. RESULTS: The porphyrin-excretion profile typical of porphyria cutanea tarda was found in only 1 of 177 patients. In the remaining 176 patients, the mean coproporphyrin level was significantly raised in HCV-positive patients and even higher in patients who were HIV- and HCV-positive. The coproporphyrin level was not correlated to the alanine aminotransferase level, the CD4+ cell count, or the HCV and HIV viremias. CONCLUSIONS: In cases of infection with HIV, HCV, or both, the development of a porphyria cutanea tarda urinary profile is a rare event (0.56% in this study), but coproporphyrin excretion is increased. This could be related to hepatic changes induced by the viruses. Our results do not support the hypothesis of a direct viral effect on the porphyrin metabolism. Infection with HIV, HCV, or both may be a major triggering factor, but is not sufficient to induce porphyria.


Assuntos
Coproporfirinas/urina , Infecções por HIV/urina , Soropositividade para HIV/urina , Hepatite C/urina , Adolescente , Adulto , Idoso , Alanina Transaminase/análise , Contagem de Linfócito CD4 , Cromatografia Líquida de Alta Pressão , Coproporfirinas/metabolismo , DNA Viral/análise , Feminino , Seguimentos , Infecções por HIV/complicações , Infecções por HIV/enzimologia , Soropositividade para HIV/complicações , Soropositividade para HIV/enzimologia , Hepatite C/complicações , Hepatite C/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Porfiria Cutânea Tardia/complicações , Porfiria Cutânea Tardia/urina , Porfirinas/metabolismo , Porfirinas/urina , Estudos Prospectivos , Viremia/virologia
19.
Acad Med ; 73(7): 790-3, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9679469

RESUMO

PURPOSE: To examine predictors identified from a review of the literature for their relationships to choice of academic medicine careers among graduates of a community-based, primary-care-oriented medical school. METHOD: All graduates from the first 14 classes of the Wright State University School of Medicine (1980-1993) were investigated in a two-part survey between fall 1996 and spring 1997. Graduates were considered academic if they were full-time, part-time, or voluntary faculty at a medical school. From the survey and medical school records, data were gathered for 29 predictive factors (demographic, academic, experiential, and attitudinal). RESULTS: Of 470 eligible graduates, 340 (72%) returned the questionnaire involving predictive factors. The medical school's database was virtually complete for these 340 graduates except for postgraduate information, which required consent from the graduate. Those in academic medicine (n = 176) did not differ significantly from those not in academic medicine (n = 164) on any of the 29 variables. CONCLUSION: No predictor of a career in academic medicine was identified for graduates of a community-based, primary-care-oriented medical school. This inconsistency with earlier research is discussed. However, community-based, primary-care-oriented medical schools are advised to proceed cautiously and not ignore those factors previously found to be predictive of an academic career at other types of medical schools.


Assuntos
Escolha da Profissão , Atenção Primária à Saúde , Centros Médicos Acadêmicos , Medicina Comunitária/educação , Docentes de Medicina , Feminino , Humanos , Masculino , Ohio , Faculdades de Medicina , Inquéritos e Questionários
20.
Eur J Gastroenterol Hepatol ; 11(7): 741-5, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10445794

RESUMO

OBJECTIVE: Beta-blockers have been shown to reduce portal pressure in patients with cirrhosis and limit the development of portosystemic shunts in portal hypertensive animals. Thus, a randomized double-blind trial was conducted to evaluate propranolol in the prevention of the development of large oesophageal varices in patients with cirrhosis without varices or with small varices. METHODS: One hundred and two patients received long-acting propranolol (160 mg/day) and 104 patients received a placebo. At inclusion, there was no significant difference between the two groups in terms of clinical characteristics or biochemical tests. At 2 years, the size of varices was estimated on video recordings. RESULTS: One-third of the patients were lost to follow-up, and 95%/97% of the remaining patients were compliant in the propranolol and placebo groups, respectively. At 2 years, the proportion of patients with large varices was 31% in the propranolol group and 14% in the placebo group (P< 0.05). Three and four patients bled in the propranolol and placebo groups, respectively, and nine and ten died, respectively. CONCLUSION: This trial suggests that propranolol administration cannot be recommended for the prevention of the development of large oesophageal varices in patients with cirrhosis; thus other studies are needed in selected subgroups of patients.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/prevenção & controle , Cirrose Hepática/complicações , Propranolol/uso terapêutico , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Falha de Tratamento
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