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1.
ESMO Open ; 9(2): 102233, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38320430

RESUMEN

BACKGROUND: Trastuzumab deruxtecan (T-DXd) has shown promising results in patients with breast cancer brain metastases (BCBMs). We conducted a systematic review and meta-analysis to evaluate the effectiveness and safety of T-DXd in the human epidermal growth factor receptor 2 (HER2)-positive BCBM population. PATIENTS AND METHODS: We searched PubMed, Embase, and Cochrane Library databases as well as American Society of Clinical Oncology (ASCO), European Society for Medical Oncology (ESMO), and San Antonio Breast Cancer Symposium (SABCS) websites for clinical trials (CTs) and observational studies evaluating T-DXd in patients with HER2-positive BCBM. Heterogeneity was assessed with I2 statistics. Random effects models were used for all statistical analyses, which were carried out using R software (version 4.2.2). RESULTS: Ten studies were included, six CTs (n = 189) and four observational studies (n = 130), with a total of 319 patients. The median progression-free survival was 15 months [95% confidence interval (CI) 13.9-16.1 months]. The objective response rate (ORR) was 61% (95% CI 52% to 70%), and the intracranial (IC)-ORR was 61% (95% CI 54% to 69%). No significant differences in ORR and IC-ORR were observed between CTs and observational studies (P = 0.31 and 0.58, respectively). The clinical benefit rate (CBR) was 80% (95% CI 52% to 94%), and the IC-CBR was 70% (95% CI 54% to 82%). The ORR was 68% (95% CI 57% to 77%) in the subgroup of patients with stable BMs and 60% (95% CI 48%-72%) in patients with active BM, with no significant difference between groups (P = 0.35). CONCLUSIONS: Our systematic review and meta-analysis supports the IC activity of T-DXd in patients with stable BM and active BM. TRIAL REGISTRATION: International Prospective Register of Systematic Reviews (PROSPERO) under the protocol number CRD42023422589.


Asunto(s)
Neoplasias Encefálicas , Neoplasias de la Mama , Camptotecina/análogos & derivados , Inmunoconjugados , Receptor ErbB-2 , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Trastuzumab/farmacología , Trastuzumab/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico
2.
Neotrop Entomol ; 47(2): 281-291, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28823094

RESUMEN

The objective of this study was to evaluate possible side effects of insecticides used in soybean crops on pupae and adults of the egg parasitoid Telenomus podisi Ashmead (Hymenoptera: Platygastridae) under laboratory conditions. The protocol was adapted from standard methodology stablished by the Pesticides and Beneficial Organisms Working Group of the International Organization for Biological and integrated Control (IOBC) for Trichogramma cacoeciae (Marchal) (Hymenoptera: Trichogrammatidae). All tested benzoylureas, diacylhydrazines, diamides and spinosins as well as pyrethroid beta-cyfluthrin were harmless to T. podisi pupae and adults, and therefore, can be used in IPM without damage to this biological control agent. The tested organophosphate, pyrethroids (except beta-cyfluthrin) and its combinations with either neonicotinoids or diamides triggered deleterious effects on at least one of the life stages of the parasitoid and should, whenever possible, be replaced by other insecticides more selective to natural enemies.


Asunto(s)
Agentes de Control Biológico , Insecticidas/toxicidad , Piretrinas/toxicidad , Avispas/efectos de los fármacos , Animales , Productos Agrícolas , Femenino , Pupa , Glycine max
3.
Neotrop Entomol ; 45(2): 192-200, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26842914

RESUMEN

The aim of this study was to compare the side-effects of glyphosate to the parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae) when parasitoids were exposed to this chemical at the pupal (inside host eggs) and adult stages. Bioassays were conducted under laboratory conditions according to the International Organization for Biological Control (IOBC) standard methods for testing side-effects of pesticides to egg parasitoids. Different glyphosate-based pesticides (Roundup Original®, Roundup Ready®, Roundup Transorb®, Roundup WG®, and Zapp Qi®) were tested at the same acid equivalent concentration. Treatments were classified following the IOBC toxicity categories as (1) harmless, (2) slightly harmful, (3) moderately harmful, and (4) harmful. When tested against T. remus adults, Roundup Original®, Roundup Ready®, Roundup Transorb®, and Roundup WG® reduced parasitism 2 days after parasitoid emergence, being classified as slightly harmful. Differently, when tested against T. remus pupae, all tested glyphosate-based products did not differ in their lethal effect and therefore did not reduce T. remus adult emergence or parasitism capacity, being classified as harmless. However, differences on sublethal toxicity were found. Parasitism of individuals emerging from parasitized eggs sprayed at the pupal stage of T. remus with Zapp Qi® was lower compared to control, but parasitism was still higher than 66%, and therefore, Zapp Qi® was still classified as harmless. In conclusion, all tested glyphosate-based products can be used in agriculture without negative impact to T. remus as none was classified as harmful or moderately harmful to this parasitoid when exposure occurred at the pupal or adult stages.


Asunto(s)
Glicina/análogos & derivados , Herbicidas/toxicidad , Himenópteros/efectos de los fármacos , Agricultura , Animales , Glicina/toxicidad , Pupa , Glifosato
4.
Cell Death Dis ; 5: e1419, 2014 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-25210802

RESUMEN

Given the complex heterogeneity of pathological changes occurring in Alzheimer's disease (AD), any therapeutic effort absolutely requires a multi-targeted approach, because attempts addressing only a single event may result ineffective. Palmitoylethanolamide (PEA), a naturally occurring lipid amide between palmitic acid and ethanolamine, seems to be a compound able to fulfill the criteria of a multi-factorial therapeutic approach. Here, we describe the anti-inflammatory and neuroprotective activities of systemic administration of PEA in adult male rats given intrahippocampal injection of beta amyloid 1-42 (Aß 1-42). Moreover, to investigate the molecular mechanisms responsible for the effects induced by PEA, we co-administered PEA with the GW6471, an antagonist of peroxisome proliferator-activated receptor-α (PPAR-α). We found that Aß 1-42 infusion results in severe changes of biochemical markers related to reactive gliosis, amyloidogenesis, and tau protein hyperphosphorylation. Interestingly, PEA was able to restore the Aß 1-42-induced alterations through PPAR-α involvement. In addition, results from the Morris water maze task highlighted a mild cognitive deficit during the reversal learning phase of the behavioral study. Similarly to the biochemical data, also mnestic deficits were reduced by PEA treatment. These data disclose novel findings about the therapeutic potential of PEA, and suggest novel strategies that hopefully could have the potential not just to alleviate the symptoms but also to modify disease progression.


Asunto(s)
Enfermedad de Alzheimer/prevención & control , Etanolaminas/administración & dosificación , Fármacos Neuroprotectores/administración & dosificación , Ácidos Palmíticos/administración & dosificación , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Amidas , Animales , Modelos Animales de Enfermedad , Gliosis , Humanos , Masculino , PPAR alfa/genética , PPAR alfa/metabolismo , Ratas , Ratas Sprague-Dawley
5.
BMC Infect Dis ; 1: 18, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11667952

RESUMEN

BACKGROUND: Many case reports of acute pancreatitis have been reported but, up to now, pancreatic abnormalities during acute gastroenteritis have not been studied prospectively. OBJECTIVES: To evaluate the incidence and the clinical significance of hyperamylasemia in 507 consecutive adult patients with acute gastroenteritis. METHODS: The clinical significance of hyperamylasemia, related predisposing factors and severity of gastroenteritis were assessed. RESULTS: Hyperamylasemia was detected in 10.2 % of patients studied. Although amylasemia was found over four times the normal values in three cases, the clinical features of acute pancreatitis were recorded in only one case (0.1%). Hyperamylasemia was more likely (17%) where a microorganism could be identified in the stools (p < 0.01). Among patients with positive stool samples, Salmonella spp. and in particular S. enteritidis, was the microorganism most frequently associated with hyperamylasemia [17/84 (20.2 %) and 10/45 (22.2%), respectively], followed by Rotavirus, Clostridium difficile and Campylobacter spp. Patients with hyperamylasemia had more severe gastroenteritis with an increased incidence of fever (80 % vs 50.6 %, O.R. 3.0; P < 0.01), dehydration (18% vs 8.5%; O.R. 2.5; P < 0.05), and a higher mean number of evacuations per day (9.2 vs 7.5; P < 0.05) than those with amylasemia in the normal range. Hyperamylasemia was significantly associated with cholelithiasis, (30.0 % vs 10.7%, O.R. 3.5; P < 0.01) and chronic gastritis or duodenal ulceration (22.0 % vs 10.2%, O.R. 2.4, P < 0.05). CONCLUSIONS: Hyperamylasemia is relatively frequent, and is associated with severe gastroenteritis. However, acute pancreatitis in the setting of acute gastroenteritis, is a rare event.


Asunto(s)
Amilasas/metabolismo , Gastroenteritis/complicaciones , Enfermedades Pancreáticas/etiología , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Enfermedades Pancreáticas/enzimología , Enfermedades Pancreáticas/epidemiología
6.
J Chemother ; 13(2): 182-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11330366

RESUMEN

From January 1991 to June 1997 217 patients undergoing monolateral or bilateral total knee replacement (TKR) were consecutively enrolled in a prospective study on the incidence of postoperative infections and related risk factors. Regional antimicrobial prophylaxis (teicoplanin 400 mg) was used in 263 (95%) prostheses implanted; in the remaining 14 implants (5%) perioperative antibiotic prophylaxis (teicoplanin 800 mg) was administered as usual by systemic route. None of the patients experienced local or systemic adverse effects. Over the 2-year follow-up period, 8 (2.9%) primary site infectious complications were recorded, i.e. 4 superficial infections, which were cured without involvement of the prostheses, and 4 deep infections, which required prosthesis removal. Six infections occurred in patients who had undergone previous surgery of the same knee joint, and 2 in patients undergoing primary TKR (p= 0.0005); diabetic patients had infections (13%) more frequently than non-diabetic patients (1.9%, p=0.01). Staphylococci were the leading organisms isolated from infections; however 3 strains of Escherichia coli were isolated from patients who had undergone a previous prosthesis implantation at the same knee joint. Regional administration of teicoplanin appears to be a safe and valuable prophylactic technique; however, in patients at risk of infection a prophylactic regimen which is also active against gram-negative bacteria should probably be considered.


Asunto(s)
Antibacterianos/farmacología , Profilaxis Antibiótica , Artroplastia de Reemplazo de Rodilla/efectos adversos , Infecciones por Bacterias Gramnegativas/epidemiología , Infección de la Herida Quirúrgica/epidemiología , Teicoplanina/farmacología , Adulto , Anciano , Antibacterianos/administración & dosificación , Femenino , Infecciones por Bacterias Gramnegativas/etiología , Infecciones por Bacterias Gramnegativas/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Teicoplanina/administración & dosificación
7.
J Gastroenterol ; 34(3): 345-50, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10433010

RESUMEN

The correlation between therapeutic response and liver fibrogenesis was studied in serum and liver specimens taken from 31 patients treated with alpha-interferon (IFN) (14 sustained responders and 17 non-responders) for chronic hepatitis C. Serum samples, collected before therapy, and at further 6-month intervals over 2 years, were tested for markers of liver neofibrogenesis. Serum N-terminal procollagen III peptide (PIIINP) displayed a significant and persistent decrease (P < 0.05) in sustained responders but not in non-responders; significantly lowered (P < 0.05) mean levels of C-terminal procollagen I peptide (PICP) were transiently observed in both patient groups, apparently as a result of IFN administration. Serum laminin (Lam) levels remained unchanged. One year after the cessation of treatment, liver biopsy re-testing showed an improvement in necro-inflammatory scores only in sustained responders, with the histological fibrosis scores remaining unaltered in both groups. IFN treatment seemed to exert an influence on serum levels of markers of hepatic connective tissue turnover even in patients that did not respond to therapy, while no effect was observed on preexistent liver fibrosis.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/sangre , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Cirrosis Hepática/patología , Fragmentos de Péptidos/sangre , Procolágeno/sangre , Adulto , Análisis de Varianza , Biomarcadores/sangre , Biopsia con Aguja , Femenino , Hepatitis C Crónica/patología , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Sensibilidad y Especificidad , Resultado del Tratamiento
8.
Mutat Res ; 436(3): 263-83, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10354525

RESUMEN

Acrylonitrile (AN) is an important intermediary for the synthesis of a variety of organic products, such as artificial fibres, household articles and resins. Although acute effects are the primary concern for an exposure to AN, potential genotoxic, carcinogenic and teratogenic risks of AN have to be taken seriously in view of the large number of workers employed in such industries and the world-wide population using products containing and possibly liberating AN. An understanding of the effect of acrylonitrile must be based on a characterization of its metabolism as well as of the resulting products and their genotoxic properties. Tests for mutagenicity in bacteria have in general been positive, those in plants and on unscheduled DNA synthesis doubtful, and those on chromosome aberrations in vivo negative. Wherever positive results had been obtained, metabolic activation of AN appeared to be a prerequisite. The extent to which such mutagenic effects are significant in man depends, however, also on the conditions of exposure. It appears from the limited data that the ultimate mutagenic factor(s), such as 2-cyanoethylene oxide, may have little opportunity to act under conditions where people are exposed because it is formed only in small amounts and is rapidly degraded. The carcinogenic action of AN has been evaluated by various agencies and ranged from 'reasonably be anticipated to be a human carcinogen' to 'cannot be excluded', the most recent evaluation being 'possibly carcinogenic to humans'. Animal data that confirm the carcinogenic potential of AN have certain limitations with respect to the choice of species, type of tumors and length of follow up. Epidemiological studies which sometimes, but not always, yielded positive results, encounter the usual difficulties of confounding factors in chemical industries. Exposure of workers to AN should continue to be carefully monitored, but AN would not have to be considered a cancer risk to the population provided limitations on releases from consumer products and guidelines on AN in water and air are enforced. AN is teratogenic in laboratory animals (rat, hamster) at high doses when foetal/embryonic (and maternal) toxicity already is manifest. Pregnant workers should not be exposed to AN. In view of the small concentrations generally encountered outside plants, women not professionally exposed would appear not to be at risk of teratogenic effects due to AN. Future research should concentrate on the elucidation of the different degradation pathways in man and on epidemiological studies in workers including pregnant women, assessing also, if possible, individual exposure by bio-monitoring.


Asunto(s)
Acrilonitrilo/toxicidad , Carcinógenos/toxicidad , Mutágenos/toxicidad , Teratógenos/toxicidad , Anomalías Inducidas por Medicamentos/etiología , Acrilonitrilo/química , Acrilonitrilo/metabolismo , Animales , Pruebas de Carcinogenicidad , Carcinógenos/química , Carcinógenos/metabolismo , Humanos , Pruebas de Mutagenicidad , Mutágenos/química , Mutágenos/metabolismo , Teratógenos/química , Teratógenos/metabolismo
9.
Infection ; 26(5): 283-7, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9795785

RESUMEN

Forty-eight persons (M = 45, F = 3; age range = 20-53, mean = 32.2) affected with chronic hepatitis C were tested for HGV/GBV-C RNA and HCV-RNA by nested PCR and DEIA in serum and in liver specimens to evaluate the prevalence and the impact of HGV/GBV-C coinfection in patients with chronic HCV-related hepatitis. Sera were also assayed for antibodies to HGV/GBV-C E2 protein. Serum HGV/GBV-RNA could be detected in nine (19%) patients, and anti-E2 antibodies in 22 (46%) patients. The presence of HGV/GBV-C RNA or anti-E2 antibodies was mutually exclusive. The cumulative prevalence of HGV/GBV-C infection was 65% (31/48); the majority of these patients (26/31, 84%) were intravenous drug users (IVDUs). In eight of nine patients viraemic for HGV/GBV-C, RNA positivity could be revealed even in liver specimens; these eight patients were also positive for HCV-RNA both in serum and the liver and did not exhibit any specific association with HCV genotype. HGV/GBV-C RNA negative strand RT-PCR testing was negative in all of the eight liver specimens, providing little support to the hypothesis that liver represents the primary site of HGV/GBV-C replication. Moreover, patients with HGV/GBV-C and HCV coinfection were comparable to those with HCV infection alone in terms of biochemistry and liver histology.


Asunto(s)
Flaviviridae/aislamiento & purificación , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/complicaciones , Hepatitis Viral Humana/complicaciones , Hígado/virología , Adulto , Femenino , Flaviviridae/genética , Hepacivirus/genética , Anticuerpos Antihepatitis/sangre , Hepatitis C Crónica/patología , Hepatitis C Crónica/virología , Hepatitis Viral Humana/patología , Hepatitis Viral Humana/virología , Humanos , Hígado/patología , Masculino , Persona de Mediana Edad , ARN Viral/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas del Envoltorio Viral/inmunología , Viremia/virología
10.
Biochem Pharmacol ; 55(7): 941-51, 1998 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-9605418

RESUMEN

The study of the adaptive response, i.e. a reduced effect from a higher challenging dose of a stressor when a smaller inducing dose had been applied a few hours earlier, has opened many new vistas into the mechanisms by which cells can adapt to hazardous environments. Although the entire chain from the initial event, supposedly the presence of DNA damage, to the end effect, presumably improved DNA repair, has not been fully elucidated, many individual links have been postulated. Initial elements--following the still unknown signal for the presence of radiation damage--are various kinases (protein kinase C and stress-activated protein kinases), which, in turn, induce early response genes whose products initiate a cascade of protein-DNA interactions that regulate gene transcription and ultimately result in specific biological responses. These responses include the activation of later genes that can promote production of growth factors and cytokines, trigger DNA repair, and regulate progress through the cell cycle. Indeed, there appears to be a relation between the induction of the adaptive response and the effects of radiation and cytostatic agents on the cell cycle, although these effects, especially the G1 delay, occur at much higher doses than the adaptive response, and one may not indiscriminately extrapolate mechanisms responsible for cell cycle changes observed at high doses, e.g. for radiation in the order of grays, to those involved in the adaptive responses at much lower doses, i.e. some tens of milligrays.


Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Daño del ADN/efectos de la radiación , Adaptación Fisiológica/genética , Animales , Antineoplásicos/toxicidad , Daño del ADN/genética , Humanos , Proteínas/genética , Proteínas/metabolismo
11.
Clin Infect Dis ; 20(2): 263-6, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7742427

RESUMEN

Thirty-one consecutive AIDS patients with cryptococcal disease were enrolled in a study of the efficacy and safety of short-course primary treatment with a relatively high dose of amphotericin B (1 mg/[kg.d] for 14 days); 26 patients also received flucytosine (100-150 mg/[kg.d], given either intravenously or orally). Twenty-five patients had cryptococcal meningitis confirmed by culture, three had presumed cryptococcal meningitis, and three had disseminated extrameningeal cryptococcosis. After successful primary treatment, all patients were given oral itraconazole or fluconazole as suppressive therapy, and their lifelong clinical and mycologic follow-up was planned. Successful primary therapy was defined as the resolution of symptoms and the documentation of negative cultures of cerebrospinal fluid and/or blood 2 months after the initial diagnosis. Therapy was successful in 29 (93.5%) of all 31 cases and in 26 (92.8%) of the 28 cases of culture-proven or presumed cryptococcal meningitis. Nephrotoxicity developed as a result of amphotericin B administration in seven cases; this adverse reaction required a reduction of the dose in two cases and the discontinuation of therapy in five. No deaths due to cryptococcosis were documented during primary therapy. Treatment failed in two cases. During a mean observation period of 10.7 months, three relapses of the underlying infection occurred. Our results indicate that an aggressive approach to the primary treatment of cryptococcosis in AIDS patients, with the administration of a relatively high dose of amphotericin B for a relatively short period, is effective and well tolerated.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Anfotericina B/uso terapéutico , Criptococosis/tratamiento farmacológico , Meningitis Criptocócica/tratamiento farmacológico , Adulto , Anfotericina B/administración & dosificación , Anfotericina B/efectos adversos , Femenino , Fluconazol/uso terapéutico , Estudios de Seguimiento , Humanos , Itraconazol/uso terapéutico , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
12.
Infection ; 22(5): 333-7, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7531180

RESUMEN

The prevalence of anti-HCV antibodies and the risk factors for HCV infection were assessed in 5,672 pregnant women living in North Italy. All reactive sera were confirmed by RIBA-2 test. Anti-HCV positive pregnant women together with an anti-HCV negative control group, were interviewed by standardised questionnaire to identify "known" or "potential" risk factors for HCV infection. The anti-HCV prevalence was 0.7% (40/5,672), higher than that observed among blood donors in the same geographical area (0.2%). The RIBA-2 assay was positive in 60% (24/40) of cases, indeterminate in 10% (4/40) and negative in 30% (12/40). As for "known" risk factors, considering RIBA-2 positivity, intravenous drug use was by far the main risk factor for HCV infection, resulting in a significantly higher risk than in the control group (50% versus 5.9% [O. R. 15.8, CI 5.4-45.5]). The ten RIBA-2 positive women without histories of transfusion or IV drug use had a significantly higher frequency of "sexual contacts with IV drug users" compared to controls (50% vs 4.9% [O. R. 19.0, CI 3.6-94.0]). In conclusion, our study provides evidence that in our geographical area the anti-HCV antibody prevalence is higher in pregnant women than in blood donors and that IV drug use and sexual contacts with IV drug users represent the most important risk factors for HCV infection among young women in North Italy.


Asunto(s)
Hepacivirus/inmunología , Anticuerpos Antihepatitis/sangre , Hepatitis C/epidemiología , Complicaciones Infecciosas del Embarazo/epidemiología , Adulto , Estudios de Casos y Controles , Femenino , Hepatitis C/etiología , Hepatitis C/inmunología , Anticuerpos contra la Hepatitis C , Humanos , Italia/epidemiología , Vigilancia de la Población , Embarazo , Complicaciones Infecciosas del Embarazo/etiología , Complicaciones Infecciosas del Embarazo/inmunología , Prevalencia , Factores de Riesgo , Estudios Seroepidemiológicos , Abuso de Sustancias por Vía Intravenosa/complicaciones , Abuso de Sustancias por Vía Intravenosa/epidemiología , Reacción a la Transfusión
13.
Antimicrob Agents Chemother ; 37(12): 2693-8, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8109937

RESUMEN

Twenty-four patients undergoing monolateral or bilateral total knee replacement (TKR) procedures were randomized to receive teicoplanin (T) either systemically or regionally. Subjects scheduled for systemic prophylaxis and undergoing monolateral (six patients) or bilateral (five patients) TKR received a single 800-mg dose of T in 100 ml of saline as a 5-min infusion into a forearm vein 2.5 h before surgery. For regional prophylaxis, patients undergoing monolateral surgery (eight subjects) received 400 mg of T in 100 ml of saline as a 5-min infusion into a foot vein of the leg to be operated on immediately after the tourniquet was inflated. For the five patients scheduled for bilateral operation and regional prophylaxis, the administration of T was also repeated for the second knee operation. The tourniquet, as the standard TKR surgical technique, was inflated to 400 mm Hg (c. 50 kPa) in all 24 patients immediately before the beginning of surgery and kept in place for the duration of the operation. Samples of serum, bone, skin, synovia, and subcutaneous tissue were collected at timed intervals during surgery. They were microbiologically assayed for T by using Bacillus subtilis as the test organism. Overall, the mean T concentrations obtained with regional route prophylaxis were found to be 2 to 10 times higher than those achieved following systemic prophylaxis. Moreover, peak levels in different tissues after regional prophylaxis were significantly higher (P < 0.05). None of the patients experienced adverse effects due to regional or systemic T administration; no prosthetic or wound infections were observed in the follow-up period (from 12 to 26 months).


Asunto(s)
Prótesis de la Rodilla/métodos , Premedicación , Teicoplanina/farmacocinética , Teicoplanina/uso terapéutico , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones Relacionadas con Prótesis/prevención & control , Teicoplanina/efectos adversos , Distribución Tisular
14.
Mutat Res ; 292(2): 199-204, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7692257

RESUMEN

The supernatant from human Hep G2 hepatoma cells was examined for typical enzymatic activities involved in the metabolism of xenobiotics. Neither cytochrome P-450 nor b5 was detectable, but associated enzymatic activities were found especially after induction with hydrocortisone (HC) and benzanthracene (BA) suggesting that this Hep G2 supernatant contains cyt P-450 IA1 and IA2. Other critical enzymes are also present, but, as expected, at lower activities than in Aroclor 1254 rat liver S9, except for NADH and NADPH cytochrome c reductase. Results of the Ames test indicate that the induced Hep G2 supernatant is a suitable activator for the evaluation of genotoxicity of indirect mutagens.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Medios de Cultivo Condicionados , Pruebas de Mutagenicidad , Animales , Biotransformación , Carcinoma Hepatocelular/enzimología , Enzimas/metabolismo , Humanos , Masculino , Mutágenos/farmacología , Ratas , Ratas Wistar , Células Tumorales Cultivadas
16.
Biochem Pharmacol ; 44(12): 2422-4, 1992 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-1472110

RESUMEN

Purified red blood cell cytosol is able to activate 2-aminofluorene (2AF) to N-hydroxy-2-aminofluorene. Apparent kinetic parameters are determined with and without methylene blue. The latter, which maintains haemoglobin in the reduced form and stimulates NADPH production, increases the affinity of the enzyme for the 2AF. This activity is inhibited by carbon monoxide while cyanide is without effect. The involvement of a peroxidative reaction or a one-electron oxidative mechanism involving free radicals may be excluded.


Asunto(s)
Eritrocitos/metabolismo , Fluorenos/metabolismo , Monóxido de Carbono , Citosol/metabolismo , Activación Enzimática , Humanos , Cinética , Masculino , Azul de Metileno , Oxigenasas de Función Mixta/metabolismo
17.
Mutat Res ; 268(1): 21-6, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1378182

RESUMEN

The induction of sister-chromatid exchanges (SCEs) and micronuclei (MN) was used as an endpoint to evaluate the cytogenetic effects of benzo[a]pyrene (B(a)P) activated by human red blood cells and S9 mix. Human erythrocytes can metabolically activate B(a)P. It was shown that both human erythrocytes and S9 mix activate B(a)P and that the resulting excess SCE and MN depend in a linear manner on the B(a)P dose. HPLC analysis suggested that quinone derivatives formed by the red blood cells are responsible for the cytogenetic abnormalities observed.


Asunto(s)
Benzo(a)pireno/toxicidad , Eritrocitos/metabolismo , Linfocitos/efectos de los fármacos , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Intercambio de Cromátides Hermanas/efectos de los fármacos , Benzo(a)pireno/metabolismo , Biotransformación , Células Cultivadas , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Humanos , Hígado/metabolismo , Extractos Hepáticos/metabolismo , Pruebas de Mutagenicidad
19.
Biochem Pharmacol ; 43(2): 207-11, 1992 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-1739409

RESUMEN

Red blood cell cytosol promotes enzymic N-demethylation reactions which display typical Michaelis-Menten kinetics with respect to N-methylaniline as substrate. The demethylase activity is linked with hemoglobin (Hb) and is enhanced in the presence of NADH and the NADH-methemoglobin reductase system. It has been adduced that Hb in its oxygenated form is involved in the reaction.


Asunto(s)
Eritrocitos/metabolismo , Oxidorreductasas N-Desmetilantes/metabolismo , Compuestos de Anilina/metabolismo , Compuestos de Anilina/farmacología , Animales , Citosol/metabolismo , Cinética , Masculino , NAD/metabolismo , NAD/farmacología , Oxihemoglobinas/metabolismo , Ratas , Ratas Endogámicas
20.
Mutat Res ; 261(4): 261-5, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1722281

RESUMEN

Purified human red blood cell cytosol was used to activate the heterocyclic amines 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) and 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) into mutagenic intermediate(s) in the Salmonella test. The liquid preincubation method in the presence of strain TA98 was utilized. In order to understand the mechanism involved in this metabolic activation, some modulators were incorporated in the medium. The results suggest that an oxygenated hemoprotein, probably oxyhemoglobin, is involved in the activation into genotoxic intermediate(s).


Asunto(s)
Carbolinas/toxicidad , Citosol/metabolismo , Mutágenos/toxicidad , Quinolinas/toxicidad , Biotransformación , Pruebas de Carcinogenicidad , Relación Dosis-Respuesta a Droga , Eritrocitos/metabolismo , Humanos , Cinética , Pruebas de Mutagenicidad , Salmonella typhimurium/efectos de los fármacos
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