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1.
ESMO Open ; 9(2): 102233, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38320430

RESUMO

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.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Camptotecina/análogos & derivados , Imunoconjugados , Receptor ErbB-2 , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico
2.
Neotrop Entomol ; 47(2): 281-291, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28823094

RESUMO

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.


Assuntos
Agentes de Controle Biológico , Inseticidas/toxicidade , Piretrinas/toxicidade , Vespas/efeitos dos fármacos , Animais , Produtos Agrícolas , Feminino , Pupa , Glycine max
3.
Neotrop Entomol ; 45(2): 192-200, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26842914

RESUMO

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.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Himenópteros/efeitos dos fármacos , Agricultura , Animais , Glicina/toxicidade , Pupa , Glifosato
4.
Cell Death Dis ; 5: e1419, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-25210802

RESUMO

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.


Assuntos
Doença de Alzheimer/prevenção & controle , Etanolaminas/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Ácidos Palmíticos/administração & dosagem , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Amidas , Animais , Modelos Animais de Doenças , Gliose , Humanos , Masculino , PPAR alfa/genética , PPAR alfa/metabolismo , Ratos , Ratos Sprague-Dawley
5.
BMC Infect Dis ; 1: 18, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11667952

RESUMO

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.


Assuntos
Amilases/metabolismo , Gastroenterite/complicações , Pancreatopatias/etiologia , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pancreatopatias/enzimologia , Pancreatopatias/epidemiologia
6.
J Chemother ; 13(2): 182-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11330366

RESUMO

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.


Assuntos
Antibacterianos/farmacologia , Antibioticoprofilaxia , Artroplastia do Joelho/efeitos adversos , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecção da Ferida Cirúrgica/epidemiologia , Teicoplanina/farmacologia , Adulto , Idoso , Antibacterianos/administração & dosagem , Feminino , Infecções por Bactérias Gram-Negativas/etiologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Teicoplanina/administração & dosagem
7.
J Gastroenterol ; 34(3): 345-50, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10433010

RESUMO

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.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/sangue , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Cirrose Hepática/patologia , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Adulto , Análise de Variância , Biomarcadores/sangue , Biópsia por Agulha , Feminino , Hepatite C Crônica/patologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Resultado do Tratamento
8.
Mutat Res ; 436(3): 263-83, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10354525

RESUMO

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.


Assuntos
Acrilonitrila/toxicidade , Carcinógenos/toxicidade , Mutagênicos/toxicidade , Teratogênicos/toxicidade , Anormalidades Induzidas por Medicamentos/etiologia , Acrilonitrila/química , Acrilonitrila/metabolismo , Animais , Testes de Carcinogenicidade , Carcinógenos/química , Carcinógenos/metabolismo , Humanos , Testes de Mutagenicidade , Mutagênicos/química , Mutagênicos/metabolismo , Teratogênicos/química , Teratogênicos/metabolismo
9.
Infection ; 26(5): 283-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9795785

RESUMO

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.


Assuntos
Flaviviridae/isolamento & purificação , Hepacivirus/isolamento & purificação , Hepatite C Crônica/complicações , Hepatite Viral Humana/complicações , Fígado/virologia , Adulto , Feminino , Flaviviridae/genética , Hepacivirus/genética , Anticorpos Anti-Hepatite/sangue , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Hepatite Viral Humana/patologia , Hepatite Viral Humana/virologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas do Envelope Viral/imunologia , Viremia/virologia
10.
Biochem Pharmacol ; 55(7): 941-51, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9605418

RESUMO

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.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Adaptação Fisiológica/genética , Animais , Antineoplásicos/toxicidade , Dano ao DNA/genética , Humanos , Proteínas/genética , Proteínas/metabolismo
11.
Clin Infect Dis ; 20(2): 263-6, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7742427

RESUMO

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.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Anfotericina B/uso terapêutico , Criptococose/tratamento farmacológico , Meningite Criptocócica/tratamento farmacológico , Adulto , Anfotericina B/administração & dosagem , Anfotericina B/efeitos adversos , Feminino , Fluconazol/uso terapêutico , Seguimentos , Humanos , Itraconazol/uso terapêutico , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
12.
Infection ; 22(5): 333-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7531180

RESUMO

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.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite/sangue , Hepatite C/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adulto , Estudos de Casos e Controles , Feminino , Hepatite C/etiologia , Hepatite C/imunologia , Anticorpos Anti-Hepatite C , Humanos , Itália/epidemiologia , Vigilância da População , Gravidez , Complicações Infecciosas na Gravidez/etiologia , Complicações Infecciosas na Gravidez/imunologia , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Reação Transfusional
13.
Antimicrob Agents Chemother ; 37(12): 2693-8, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8109937

RESUMO

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).


Assuntos
Prótese do Joelho/métodos , Pré-Medicação , Teicoplanina/farmacocinética , Teicoplanina/uso terapêutico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/prevenção & controle , Teicoplanina/efeitos adversos , Distribuição Tecidual
14.
Mutat Res ; 292(2): 199-204, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7692257

RESUMO

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.


Assuntos
Carcinoma Hepatocelular/metabolismo , Meios de Cultivo Condicionados , Testes de Mutagenicidade , Animais , Biotransformação , Carcinoma Hepatocelular/enzimologia , Enzimas/metabolismo , Humanos , Masculino , Mutagênicos/farmacologia , Ratos , Ratos Wistar , Células Tumorais Cultivadas
16.
Biochem Pharmacol ; 44(12): 2422-4, 1992 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-1472110

RESUMO

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.


Assuntos
Eritrócitos/metabolismo , Fluorenos/metabolismo , Monóxido de Carbono , Citosol/metabolismo , Ativação Enzimática , Humanos , Cinética , Masculino , Azul de Metileno , Oxigenases de Função Mista/metabolismo
17.
Mutat Res ; 268(1): 21-6, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1378182

RESUMO

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.


Assuntos
Benzo(a)pireno/toxicidade , Eritrócitos/metabolismo , Linfócitos/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Troca de Cromátide Irmã/efeitos dos fármacos , Benzo(a)pireno/metabolismo , Biotransformação , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Humanos , Fígado/metabolismo , Extratos Hepáticos/metabolismo , Testes de Mutagenicidade
19.
Biochem Pharmacol ; 43(2): 207-11, 1992 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-1739409

RESUMO

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.


Assuntos
Eritrócitos/metabolismo , Oxirredutases N-Desmetilantes/metabolismo , Compostos de Anilina/metabolismo , Compostos de Anilina/farmacologia , Animais , Citosol/metabolismo , Cinética , Masculino , NAD/metabolismo , NAD/farmacologia , Oxiemoglobinas/metabolismo , Ratos , Ratos Endogâmicos
20.
Mutat Res ; 261(4): 261-5, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1722281

RESUMO

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).


Assuntos
Carbolinas/toxicidade , Citosol/metabolismo , Mutagênicos/toxicidade , Quinolinas/toxicidade , Biotransformação , Testes de Carcinogenicidade , Relação Dose-Resposta a Droga , Eritrócitos/metabolismo , Humanos , Cinética , Testes de Mutagenicidade , Salmonella typhimurium/efeitos dos fármacos
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