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1.
ESMO Open ; 7(1): 100336, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34953399

RESUMEN

INTRODUCTION: Microsatellite instability (MSI) testing and tumor mutational burden (TMB) are genomic biomarkers used to identify patients who are likely to benefit from immune checkpoint inhibitors. Pembrolizumab was recently approved by the Food and Drug Administration for use in TMB-high (TMB-H) tumors, regardless of histology, based on KEYNOTE-158. The primary objective of this retrospective study was real-world applicability and use of immunotherapy in TMB/MSI-high patients to lend credence to and refine this biomarker. METHODS: Charts of patients with advanced solid tumors who had MSI/TMB status determined by next generation sequencing (NGS) (FoundationOne CDx) were reviewed. Demographics, diagnosis, treatment history, and overall response rate (ORR) were abstracted. Progression-free survival (PFS) was determined from Kaplan-Meier curves. PFS1 (chemotherapy PFS) and PFS2 (immunotherapy PFS) were determined for patients who received immunotherapy after progressing on chemotherapy. The median PFS2/PFS1 ratio was recorded. RESULTS: MSI-high or TMB-H [≥20 mutations per megabase (mut/MB)] was detected in 157 adults with a total of 27 distinct tumor histologies. Median turnaround time for NGS was 73 days. ORR for most recent chemotherapy was 34.4%. ORR for immunotherapy was 55.9%. Median PFS for patients who received chemotherapy versus immunotherapy was 6.75 months (95% confidence interval, 3.9-10.9 months) and 24.2 months (95% confidence interval, 9.6 months to not reached), respectively (P = 0.042). Median PFS2/PFS1 ratio was 4.7 in favor of immunotherapy. CONCLUSION: This real-world study reinforces the use of TMB as a predictive biomarker. Barriers exist to the timely implementation of NGS-based biomarkers and more data are needed to raise awareness about the clinical utility of TMB. Clinicians should consider treating TMB-H patients with immunotherapy regardless of their histology.


Asunto(s)
Inmunoterapia , Inestabilidad de Microsatélites , Neoplasias , Adulto , Biomarcadores de Tumor/genética , Humanos , Neoplasias/genética , Neoplasias/terapia , Estudios Retrospectivos
5.
Horm Metab Res ; 43(6): 386-90, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21448845

RESUMEN

Insulin and insulin like-growth factor-I (IGF-I) participate in the regulation of ovarian steroidogenesis. In insulin resistant states ovaries remain sensitive to insulin because insulin can activate alternative signaling pathways, such as phosphatidylinositol-3-kinase (PI-3 kinase) and mitogen-activated protein-kinase (MAPK) pathways, as well as insulin receptors and type 1 IGF receptors. We investigated the roles of MAPK-Erk1/2 and MAPK-p38 in insulin and IGF-I signaling pathways for progesterone production in human ovarian cells. Human ovarian cells were cultured in tissue culture medium in the presence of varying concentrations of insulin or IGF-I, with or without PD98059, a specific MAPK-Erk1/2 inhibitor, with or without SB203580, a specific MAPK-p38 inhibitor or with or without a specific PI-3-kinase inhibitor LY294002. Progesterone concentrations were measured using radioimmunoassay. PD98059 alone stimulated progesterone production in a dose-dependent manner by up to 65% (p<0.001). Similarly, LY294002 alone stimulated progesterone production by 13-18% (p<0.005). However, when used together, PD98059 and LY294002 inhibited progesterone production by 17-20% (p<0.001). SB203580 alone inhibited progesterone production by 20-30% (p<0.001). Insulin or IGF-I alone stimulated progesterone production by 40-60% (p<0.001). In insulin studies, PD98059 had no significant effect on progesterone synthesis while SB203580 abolished insulin-induced progesterone production. Either PD98059 or SB203580 abolished IGF-I-induced progesterone production. Both MAPK-Erk1/2 and MAPK-p38 participate in IGF-I-induced signaling pathways for progesterone production, while insulin-induced progesterone production requires MAPK-p38, but not MAPK-Erk1/2. These studies provide further evidence for divergence of insulin and IGF-I signaling pathways for human ovarian cell steroidogenesis.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Insulina/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ovario/citología , Progesterona/biosíntesis , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Adulto , Células Cultivadas , Femenino , Flavonoides/farmacología , Humanos , Imidazoles/farmacología , Persona de Mediana Edad , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Ovario/efectos de los fármacos , Ovario/enzimología , Fosforilación/efectos de los fármacos , Piridinas/farmacología , Adulto Joven
6.
Oncogene ; 27(34): 4712-23, 2008 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-18408758

RESUMEN

Cancer progression is an abnormal form of tissue repair characterized by chronic inflammation. IkappaB kinase-beta (IKKbeta) required for nuclear factor-kappaB (NF-kappaB) activation plays a critical role in this process. Using EOC cells isolated from malignant ovarian cancer ascites and solid tumors, we identified IKKbeta as a major factor promoting a functional TLR-MyD88-NF-kappaB pathway that confers to EOC cell the capacity to constitutively secrete proinflammatory/protumor cytokines and therefore promoting tumor progression and chemoresistance. Furthermore, we describe for the first time the identification of the microRNA hsa-miR-199a as a regulator of IKKbeta expression. Our study describes the property of ovarian cancer cells to enhance the inflammatory microenvironment as a result of the expression of an active IKKbeta pathway. Identification of these markers in patients' tumor samples may facilitate the adequate selection of treatment and open new venues for the development of effective therapy for chemoresistant ovarian cancers.


Asunto(s)
Quinasa I-kappa B/genética , MicroARNs/fisiología , FN-kappa B/metabolismo , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Secuencia de Bases , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Modelos Biológicos , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico , Transfección , Células Tumorales Cultivadas
7.
Int J Gynecol Cancer ; 17(2): 379-86, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17362316

RESUMEN

This phase I study sought to determine the toxicity profile, pharmacokinetics, and antitumor activity of giving carboplatin every 3 weeks and paclitaxel weekly in patients with relapsed ovarian cancer. Eligible patients with relapsed epithelial ovarian cancer and prior treatment with platinum- and paclitaxel-based therapy were treated with an escalating regimen of carboplatin (day 1) at an area under the curve (AUC) of 4-6 and 1-h infusions of paclitaxel (days 1, 8, and 15) at 50-80 mg/m(2) cycled at 3-week intervals. Pharmacokinetic studies were performed on the first day of cycles 1 and 2. All patients had a platinum-free interval of greater than 6 months from the most recent platinum treatment. A total of 77 cycles were administered to 16 patients, with a similar median number of cycles per patient at each dose level varying from 4.6 to 5.3. Febrile neutropenia and grade 4 thrombocytopenia were the dose-limiting toxicities at dose levels 3 and 4 after the third cycle, with no mucositis, nausea, vomiting, or peripheral neuropathy observed greater than grade 2. The maximum tolerated dose of carboplatin was an AUC of 5 and 80 mg/m(2) for paclitaxel. Pharmacokinetic analysis showed a marginal statistical difference with regard to reduced systemic paclitaxel concentration after cycle 2 compared with cycle 1 (P= 0.06). Of nine patients evaluable for a radiographic response, the response rate was 66.6% with a complete response of 33.3%. All five patients with nonmeasurable disease achieved a biochemical response. The combination of carboplatin given every 3 weeks at an AUC of 5 and 1-h weekly paclitaxel at 80 mg/m(2) is a feasible and reasonably well-tolerated regimen and may have significant antitumor activity in relapsed ovarian cancer patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/administración & dosificación , Carcinoma/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Paclitaxel/administración & dosificación , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Carboplatino/efectos adversos , Carboplatino/farmacocinética , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Enfermedades Hematológicas/inducido químicamente , Enfermedades Hematológicas/terapia , Humanos , Dosis Máxima Tolerada , Persona de Mediana Edad , Paclitaxel/efectos adversos , Paclitaxel/farmacocinética , Transfusión de Plaquetas , Resultado del Tratamiento
8.
Int J Gynecol Cancer ; 16(3): 1165-71, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16803501

RESUMEN

The aim of this study was to evaluate the activity and toxicity of a tirapazamine (TPZ)/cisplatin drug combination in patients with stage IV or recurrent cervical cancer. The chemotherapy was administered for a maximum of eight cycles every 21 days. TPZ was administered intravenously at 330 mg/m(2) over a 2-h infusion, followed 1 h later by cisplatin intravenously at 75 mg/m(2) over 1 h on day 1. All patients received antiemetics including dexamethasone, ondansetron, and lorazepam. Subsequent doses were unchanged, reduced, or omitted according to observed toxicity and protocol guidelines. Response evaluation was performed every two cycles. Thirty-six patients with stage IV or recurrent cervical cancer were treated. Ninety-four percent of patients had prior radiotherapy. Two patients had prior chemotherapy. There were two complete responses and eight partial responses (27.8%). An additional 11 patients (30.6%) had stable disease as their best response. Response rate was greater in tumors outside of the previously radiated field (44.4% vs 11.1%). The median time to progression was 32.7 weeks. The most frequent grade 3 or 4 adverse events were nausea, vomiting, and fatigue, which occurred in 30.6%, 25%, and 22% of subjects, respectively. Anemia was the most frequent grade 3 or 4 hematologic toxicity at 8.3%. We conclude that the combination of cisplatin and TPZ was reasonably well tolerated in patients with recurrent or advanced cervical cancer. Further evaluation of this drug combination may be warranted.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma/tratamiento farmacológico , Cisplatino/administración & dosificación , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Adulto , Anciano , Agranulocitosis/inducido químicamente , Anemia/inducido químicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma/mortalidad , Cisplatino/efectos adversos , Vías de Administración de Medicamentos , Esquema de Medicación , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , Neutropenia/inducido químicamente , Análisis de Supervivencia , Trombocitopenia/inducido químicamente , Tirapazamina , Resultado del Tratamiento , Triazinas/administración & dosificación , Triazinas/efectos adversos , Neoplasias del Cuello Uterino/mortalidad
9.
Gynecol Oncol ; 94(2): 567-71, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15297205

RESUMEN

INTRODUCTION: Endometrial stromal tumors with sex-cord-like elements are relatively rare. We report a case of this neoplasm with prolactin as a tumor marker for recurrent disease. We also report response of recurrent disease to progesterone and aromatase inhibitor. CASE REPORT: A 48-year-old woman was diagnosed with Stage I endometrial stroma sarcoma with sex-cord component at the time of hysterectomy for presumed fibroid uterus. One and a half years later, she presented with recurrent disease in the abdomen associated with breast tenderness, galactorrhea, and an elevated prolactin level. She received three cycles of BEP (Bleomycin, Etoposide, Cisplatin) with partial response and followed by an optimal debulking procedure. Two out of a six additional planned cycles of BEP were administered with complete tumor response and normalized prolactin level. Second recurrence, 9 months later, again presented with galactorrhea and rising prolactin. Disease was progressive through three cycles of Docetaxel and Gemcitabine therapy, but had an objective response to treatment with anastrozole and megestrol acetate. Prolactin level normalized. Two years later there is stable disease and the patient remains symptom-free. DISCUSSION: Endometrial stromal sarcoma with sex-cord stromal component may be hormonally functional. Similarly to pure endometrial stromal sarcomas, they may respond to hormonal treatment, and further study is warranted.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias Endometriales/tratamiento farmacológico , Inhibidores Enzimáticos/uso terapéutico , Acetato de Megestrol/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Nitrilos/uso terapéutico , Sarcoma Estromático Endometrial/tratamiento farmacológico , Triazoles/uso terapéutico , Anastrozol , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inhibidores de la Aromatasa , Neoplasias Endometriales/metabolismo , Neoplasias Endometriales/patología , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Progestinas/antagonistas & inhibidores , Prolactina/biosíntesis , Sarcoma Estromático Endometrial/metabolismo , Sarcoma Estromático Endometrial/patología
10.
J Bacteriol ; 181(18): 5600-5, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10482499

RESUMEN

The coenzyme B(12)-dependent isobutyryl coenzyme A (CoA) mutase (ICM) and methylmalonyl-CoA mutase (MCM) catalyze the isomerization of n-butyryl-CoA to isobutyryl-CoA and of methylmalonyl-CoA to succinyl-CoA, respectively. The influence that both mutases have on the conversion of n- and isobutyryl-CoA to methylmalonyl-CoA and the use of the latter in polyketide biosynthesis have been investigated with the polyether antibiotic (monensin) producer Streptomyces cinnamonensis. Mutants prepared by inserting a hygromycin resistance gene (hygB) into either icmA or mutB, encoding the large subunits of ICM and MCM, respectively, have been characterized. The icmA::hygB mutant was unable to grow on valine or isobutyrate as the sole carbon source but grew normally on butyrate, indicating a key role for ICM in valine and isobutyrate metabolism in minimal medium. The mutB::hygB mutant was unable to grow on propionate and grew only weakly on butyrate and isobutyrate as sole carbon sources. (13)C-labeling experiments show that in both mutants butyrate and acetoacetate may be incorporated into the propionate units in monensin A without cleavage to acetate units. Hence, n-butyryl-CoA may be converted into methylmalonyl-CoA through a carbon skeleton rearrangement for which neither ICM nor MCM alone is essential.


Asunto(s)
Proteínas Bacterianas , Isomerasas/genética , Isomerasas/metabolismo , Metilmalonil-CoA Mutasa/genética , Metilmalonil-CoA Mutasa/metabolismo , Streptomyces/enzimología , Streptomyces/genética , Isótopos de Carbono , Farmacorresistencia Microbiana/genética , Sustancias Macromoleculares , Monensina/biosíntesis , Monensina/química , Mutagénesis Insercional , Fenotipo , Streptomyces/crecimiento & desarrollo
11.
Eur J Cardiothorac Surg ; 14(4): 403-8, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9845146

RESUMEN

OBJECTIVE: The validity of video-assisted thoracoscopic pericardial fenestration was prospectively assessed for loculated effusions. effusions previously treated by percutaneous catheter manoeuvres and those with concurrent pleural diseases. METHODS: Inclusion criteria consisted of echocardiographically documented pericardial effusions requiring diagnosis or relief of symptoms and recurrent effusions after failed percutaneous drainage and balloon pericardiotomy. Pre-operative CT-scan was used to delineate additional pleural pathology and to determine the side of intervention. All patients were followed clinically and by echocardiographic examination 3 months post-operatively. RESULTS: Twenty-four patients underwent thoracoscopic pericardial fenestration with 11 patients (54%) being previously treated by percutaneous catheter drainage, balloon pericardiotomy or subxyphoidal fenestration. Pre-operative echocardiography revealed septation and loculation in 18 patients (72%). Additional pleural pathology was identified on CT scan in 12 patients (50%) and talc pleurodesis was performed in six patients, all suffering from malignant pleural effusion. The mean operation time was 45 min (range 30-60 min) with no complications being observed. All patients were followed 3 months post-operatively by clinical and echocardiographic examination; relief of symptoms was achieved in all patients but echocardiography showed a recurrence in one patient (4%). Another recurrence was found by echocardiography after a mean follow-up time of 33 months in the 12 patients suffering from a non-malignant pericardial effusion. No recurrence of pleural or pericardial effusion was observed in the subset of patients with talc pleurodesis. CONCLUSION: Video-assisted thoracoscopic pericardial fenestration is safe and effective for loculated pericardial effusions previously treated by percutaneous drainage manoeuvres and those with concomitant pleural disease.


Asunto(s)
Endoscopía , Derrame Pericárdico/cirugía , Pericardiectomía/métodos , Toracoscopía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cateterismo , Drenaje , Ecocardiografía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Derrame Pericárdico/complicaciones , Derrame Pericárdico/diagnóstico por imagen , Derrame Pleural/complicaciones , Derrame Pleural/terapia , Derrame Pleural Maligno/complicaciones , Derrame Pleural Maligno/terapia , Pleurodesia , Estudios Prospectivos , Recurrencia , Reproducibilidad de los Resultados , Seguridad , Talco/administración & dosificación , Factores de Tiempo , Tomografía Computarizada por Rayos X , Grabación en Video
12.
Am J Gastroenterol ; 93(9): 1478-82, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9732929

RESUMEN

OBJECTIVES: Adequate preparation of the bowel is essential for accurate colonoscopic examination. We compared colonic preparation with sodium picosulphate plus magnesium citrate (SPS-Mg) with sulphate-free polyethylene glycol electrolyte lavage (PEG-EL) solution before colonoscopy, for quality of bowel cleansing, patient discomfort, and side effects. METHODS: Sixty-eight consecutive patients were randomly assigned to receive either 3 sachets of SPS-Mg (16.5 g each) (n = 39) or 3 L of PEG-EL (n = 29) on the day before colonoscopy. Shortly before the procedure each patient was interviewed to determine the degree of discomfort (1 = none or mild, 2 = moderate, 3 = severe) and side effects. The quality of bowel cleansing was graded by a gastroenterologist who was unaware of the method of preparation (from 1 = poor to 4 = excellent). RESULTS: Of the 29 PEG-EL patients, four (14%) did not complete the preparation because of side effects. The degree of discomfort was significantly greater with PEG-EL (mean score, 2.3 +/- 0.7) than with SPS-Mg (mean score, 1.4 +/- 0.5; p < 0.01). Nausea and vomiting were significantly more common in the PEG-EL group (38% vs 13%; p < 0.05). Using intention-to-treat analysis, bowel cleansing proved to be significantly better with SPS-Mg than with PEG-EL (mean score +/- SD, 3.05 +/- 0.9 and 2.57 +/- 1.0, respectively; p = 0.036). CONCLUSIONS: Colonic preparation with SPS-Mg is better tolerated, associated with significantly fewer side effects, and results in higher quality bowel cleansing than preparation with PEG-EL.


Asunto(s)
Catárticos , Ácido Cítrico , Colonoscopía , Compuestos Organometálicos , Picolinas , Polietilenglicoles , Adulto , Anciano , Anciano de 80 o más Años , Catárticos/efectos adversos , Citratos , Ácido Cítrico/efectos adversos , Colon , Femenino , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organometálicos/efectos adversos , Picolinas/efectos adversos , Polietilenglicoles/efectos adversos , Estudios Prospectivos , Irrigación Terapéutica
13.
J Biol Chem ; 273(11): 6508-17, 1998 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-9497386

RESUMEN

Purification of the coenzyme B12-dependent isobutyryl-CoA mutase (ICM) from Streptomyces cinnamonensis gave a protein of approximately 65 kDa by SDS-polyacrylamide gel electrophoresis, whose gene icmA was cloned using sequences derived from tryptic peptide fragments. The gene encodes a protein of 566 residues (62, 487 Da), with 43-44% sequence identity to the large subunit of methylmalonyl-CoA mutase (MCM) from S. cinnamonensis and Propionibacterium shermanii. Targeted disruption of the icmA gene yielded an S. cinnamonensis mutant devoid of ICM activity. The IcmA protein is approximately 160 residues shorter than the large subunit of the bacterial MCMs, corresponding to a loss of the entire C-terminal coenzyme B12 binding domain. The sequence of the (beta/alpha)8-barrel comprising residues A1-A400 in P. shermanii MCM is highly conserved in IcmA. The protein was produced in Streptomyces lividans and Escherichia coli with an N-terminal His6 tag (His6-IcmA), but after purification His6-IcmA showed no ICM activity. In the presence of coenzyme B12, protein from S. lividans and S. cinnamonensis of approximately 17 kDa by SDS-polyacrylamide gel electrophoresis could be selectively eluted with His6-IcmA from a Ni2+ affinity column. After purification, this small subunit showed no ICM activity but gave active enzyme when recombined with coenzyme B12 and IcmA or His6-IcmA.


Asunto(s)
Proteínas Bacterianas , Cobamidas/metabolismo , Genes Bacterianos , Isomerasas/genética , Streptomyces/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Expresión Génica , Isomerasas/metabolismo , Metilmalonil-CoA Mutasa/genética , Datos de Secuencia Molecular , Mutagénesis Insercional , Proteínas Recombinantes/metabolismo , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Streptomyces/enzimología
14.
Swiss Surg ; 3(4): 181-4, 1997.
Artículo en Alemán | MEDLINE | ID: mdl-9340135

RESUMEN

A 58-year old lady, involved in a head-on motor vehicle crash suffered a severe intestinal injury associated with an intimal flap lesion of the distal abdominal aorta. Thrombotic occlusion of the aortic bifurcation with clinical evidence of lower extremity ischemia was noted. The management of blunt injury to the abdominal aorta is discussed with special regard to placing prosthetic material in a potentially infected field.


Asunto(s)
Traumatismos Abdominales/diagnóstico , Aorta Abdominal/lesiones , Rotura de la Aorta/diagnóstico , Heridas no Penetrantes/diagnóstico , Traumatismos Abdominales/cirugía , Aorta Abdominal/cirugía , Rotura de la Aorta/cirugía , Prótesis Vascular , Femenino , Humanos , Isquemia/diagnóstico , Isquemia/cirugía , Pierna/irrigación sanguínea , Persona de Mediana Edad , Trombosis/diagnóstico , Trombosis/cirugía , Tomografía Computarizada por Rayos X , Heridas no Penetrantes/cirugía
15.
Gene ; 177(1-2): 217-22, 1996 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-8921870

RESUMEN

The catabolism of branched chain amino acids, especially valine, appears to play an important role in furnishing building blocks for macrolide antibiotic biosynthesis. To determine for the first time the importance of valine dehydrogenase (vdh) in polyether antibiotic biosynthesis, the vdh gene from Streptomyces cinnamonensis has been cloned and sequenced. The enzyme (M(r)37,718 Da) has been produced in large amounts in an active form in the E. coli cytoplasm using a T7 RNA-polymerase expression system. Upon inactivation of the gene in S. cinnamonensis by a double-crossover mechanism, a hyg::vdh mutant was isolated that was devoid of vdh activity. Upon growth in chemically defined media, as well as a complex medium optimised for monensin production, the mutant and wild-type grew equally well and reached the same levels of monensin production. In both strains a valine transaminase activity could be detected that provides an alternative route for converting valine into 2-oxoisovaleric acid. The results show that vdh is not essential for normal growth of S. cinnamonensis, and its inactivation does not significantly affect normal levels of monensin production in this strain.


Asunto(s)
Aminoácido Oxidorreductasas/genética , Antibacterianos/biosíntesis , Cinamatos , Monensina/biosíntesis , Streptomyces/enzimología , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Bacteriano , Farmacorresistencia Microbiana/genética , Escherichia coli , Éteres , Genes Bacterianos , Higromicina B/análogos & derivados , Higromicina B/farmacología , Datos de Secuencia Molecular , Mutagénesis Insercional , Streptomyces/genética
16.
Can J Psychiatry ; 41(4): 239-44, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8726790

RESUMEN

OBJECTIVE: This study was performed to compare the clinical efficacy, side effects, and safety of paroxetine and maprotiline, the latter being the most frequently prescribed antidepressant in Switzerland. METHOD: Seventy-one patients (in and outpatients) with major depression were randomly allocated to treatment with paroxetine (20 to 40 mg daily) or with maprotiline (50 to 150 mg daily). Efficacy was measured by means of the Hamilton Psychiatric Rating Scale for Depression, the Montgomery-Asberg Depression Rating Scale, the Clinical Global Impression, and the Hopkins Symptom Checklist. RESULTS: The 2 components showed a similar efficacy. The adverse effect profile was comparable in the 2 treatment groups, although the findings showed a nonsignificant trend pointing in the direction of lower side effects with paroxetine. CONCLUSION: In the moderate dose regimens tested, the 2 components seemed to be of similar efficacy, with comparable profiles of side effects and safety.


Asunto(s)
Antidepresivos/uso terapéutico , Trastorno Depresivo/tratamiento farmacológico , Maprotilina/uso terapéutico , Paroxetina/uso terapéutico , Adolescente , Adulto , Anciano , Antidepresivos/efectos adversos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Maprotilina/efectos adversos , Persona de Mediana Edad , Paroxetina/efectos adversos , Seguridad
17.
Am J Gastroenterol ; 91(1): 101-4, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8561106

RESUMEN

OBJECTIVES: Bacterial attachment is a prerequisite for colonization of the gastric epithelial surface. Recently, it was demonstrated that the receptor for Helicobacter pylori is the blood group antigen Lewis b, which is exposed only in blood group O. We prospectively examined the prevalence of blood groups in H. pylori-positive and -negative patients. To avoid a genetic bias, we compared blood group prevalence of our patients with the general population of Israel. METHODS: In the 187 consecutive patients we studied, in addition to regular upper endoscopy, H. pylori status and blood group. Exposure to H. pylori was diagnosed when the results of two or more of three methods were found to be positive. RESULTS: Exposure was found in 123 patients and 64 negative. The groups were similar in average age and origin, and no significant difference was demonstrated for blood group. Blood group distribution between any given origin was not significantly different in our patients and in a sample of 182,701 blood donors. CONCLUSIONS: Positivity for H. pylori was not associated with blood group O. Our observation does not support the conclusion that the receptor for H. pylori in the gastric mucosa is the blood group antigen Lewis b.


Asunto(s)
Antígenos de Grupos Sanguíneos , Infecciones por Helicobacter/sangre , Helicobacter pylori , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Infecciones por Helicobacter/etnología , Humanos , Israel/epidemiología , Judíos/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Úlcera Péptica/sangre , Úlcera Péptica/etnología , Prevalencia , Estudios Prospectivos
18.
Toxicol Lett ; 75(1-3): 101-9, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7863516

RESUMEN

Carbamide peroxide is the active ingredient in many at-home patient-applied tooth whiteners. The cytotoxicity of carbamide peroxide, as related to oxidative stress, was evaluated in vitro with several human cell lines, including Smulow-Glickman (S-G) gingival epithelial cells. The potency of carbamide peroxide was related to its hydrogen peroxide component rather than to carbamide, was eliminated in the presence of exogenous catalase, and was enhanced in the presence of aminotriazole, an inhibitor of cellular catalase. The intracellular level of glutathione, a scavanger of toxic oxygen metabolites, was decreased in cells exposed to carbamide peroxide; at higher concentrations of carbamide peroxide, leakage of lactic acid dehydrogenase was also evident. Cells pretreated with the glutathione-depleting agents, buthionine sulfoximine, chlorodinitrobenzene, and bis(chloroethyl) nitrosourea, were hypersensitive to subsequent challenge with carbamide peroxide. Conversely, pretreatment with the iron chelator, deferoxamine, protected the cells against subsequent exposure to carbamide peroxide.


Asunto(s)
Supervivencia Celular/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Peróxidos/toxicidad , Urea/análogos & derivados , Peróxido de Carbamida , Línea Celular , Combinación de Medicamentos , Glutatión/metabolismo , Humanos , L-Lactato Deshidrogenasa/metabolismo , Urea/toxicidad
19.
J Thorac Cardiovasc Surg ; 107(6): 1410-5, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8196381

RESUMEN

In a prospective study (June 1990 to June 1993), 79 patients were treated for spontaneous pneumothorax by video-assisted thoracoscopic methods with regular follow-up. The observation time was from 3 to 36 months (mean 19.6 months) and was more than 24 months in 27 patients. In 57 patients spontaneous pneumothorax was primary and in 22 secondary. The 53 male and 26 female patients were aged between 17 and 87 years (mean 37 years). Twenty-one patients were treated thoracoscopically for first episode, 22 for persistent pneumothorax (> 7 days), and 36 for a recurrence. Endoscopic examination failed to reveal any lung alteration in four patients (5.1%), and treatment then consisted of simple drainage. Leaks were sealed 26 times by means of a Roeder loop with local anesthesia and 14 times by wedge resection with endotracheal anesthesia and one-lung ventilation; 34 patients were treated by pleurectomy. No deaths occurred. Surgical morbidity was 3.8%, and the postoperative complication rate was 5.1%. One patient was excluded from the follow-up study after conversion to a thoracotomy for control of arterial bleeding. We noted six recurrences; four occurred in the first 21 days and three after ligation of the leak with a Roeder loop. We conclude that video-assisted thoracoscopic treatment of spontaneous pneumothorax by wedge resection and pleurectomy has a recurrence-free rate of 93.8% (45/48) and is therefore an effective treatment for all forms of spontaneous pneumothorax.


Asunto(s)
Laparoscopios , Neumotórax/cirugía , Toracoscopía/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Femenino , Estudios de Seguimiento , Humanos , Complicaciones Intraoperatorias , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recurrencia , Televisión , Cirugía Torácica/instrumentación , Cirugía Torácica/métodos , Toracoscopios , Resultado del Tratamiento
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