RESUMO
Neuralgic amyotrophy, brachial neuritis or Parsonage-Turner syndrome is a rare neuromuscular involvement of unknown aetiology. When it onsets in connection with a health care act, such as childbirth or surgery, a malpractice argument is often used as a cause of adverse outcome, usually due to an incorrect position of the patient on the operating table, a circumstance which directly involves the anesthesia area. Three cases are presented of Parsonage-Turner syndrome following very different surgery, with different results as regards prognosis. A review and discussion of bibliography is presented on the possibility that such circumstances are the subject of malpractice claims. Special emphasis is placed on the most currently accepted aetiopathogenic theories, and the relationship of this syndrome with the surgical act as a determining medico-legal aspect. Valuation parameters are proposed.
Assuntos
Neurite do Plexo Braquial , Humanos , Imperícia , Mesas Cirúrgicas , PrognósticoRESUMO
Water quality assessment requires a continuous and strict analysis of samples to guarantee compliance with established standards. Nowadays, the increasing number of pollutants and their synergistic effects lead to the development general toxicity bioassays capable to analyse water pollution as a whole. Current general toxicity methods, e.g. Microtox(®), rely on long operation protocols, the use of complex and expensive instrumentation and sample pre-treatment, which should be transported to the laboratory for analysis. These requirements delay sample analysis and hence, the response to avoid an environmental catastrophe. In an attempt to solve it, a fast (15 min) and low-cost toxicity bioassay based on the chromatic changes associated to bacterial ferricyanide reduction is here presented. E. coli cells (used as model bacteria) were stably trapped on low-cost paper matrices (cellulose-based paper discs, PDs) and remained viable for long times (1 month at -20 °C). Apart from bacterial carrier, paper matrices also acted as a fluidic element, allowing fluid management without the need of external pumps. Bioassay evaluation was performed using copper as model toxic agent. Chromatic changes associated to bacterial ferricyanide reduction were determined by three different transduction methods, i.e. (i) optical reflectometry (as reference method), (ii) image analysis and (iii) visual inspection. In all cases, bioassay results (in terms of half maximal effective concentrations, EC50) were in agreement with already reported data, confirming the good performance of the bioassay. The validation of the bioassay was performed by analysis of real samples from natural sources, which were analysed and compared with a reference method (i.e. Microtox). Obtained results showed agreement for about 70% of toxic samples and 80% of non-toxic samples, which may validate the use of this simple and quick protocol in the determination of general toxicity. The minimum instrumentation requirements and the simplicity of the bioassay open the possibility of in-situ water toxicity assessment with a fast and low-cost protocol.
Assuntos
Aliivibrio fischeri/química , Bioensaio/instrumentação , Escherichia coli/química , Ferricianetos/química , Papel , Testes de Toxicidade , Escherichia coli/ultraestrutura , Microscopia Eletrônica de Varredura , Oxirredução , Solo/químicaRESUMO
Environmental Risk Assessment of chemical products and effluents within EC countries require the use of cost effective standardized toxicity tests that in most cases are restricted to acute responses to high doses. Thus, subtle ecological effects are underestimated. Here we propose a short-term one day Daphnia magna feeding inhibition test as a cost effective and ecological relevant sublethal bioassay. The sensitivity and reliability of the proposed bioassay was tested in the laboratory against standardized bacteria, algae growth, D. magna and fish acute toxicity test by using 16 chemical mixture x water type combinations that included four different water types fortified with four complex chemical mixtures. Water types included ASTM hard water and three selected effluents diluted 1/10 in water to mimic worse field situations that many overexploited arid river ecosystems suffer during summer months when effluents are discharged into them with little dilution. The results obtained denoted a greater sensitivity of the proposed feeding bioassay in 51 out of 65 tests performed with an average sensitivity 50 fold greater than that of the standardized tests. The greater differences were obtained for mixtures that included narcotic chemicals and the lowest differences for those containing pesticides. Furthermore, feeding responses to the studied contaminant mixtures behaved differently to increasing TOC content than those based on bioluminescent bacteria and algae. Increasing TOC coming from sewage treated effluents decrease toxicity to the latter bioassays but increased those of D. magna feeding bioassays. These results empathize the need to include additional bioassays to monitor more accurately and realistically the toxicity of effluents or surface waters dominated by effluent discharges, a quite common situation in America and Mediterranean arid regions.
Assuntos
Daphnia/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Água/química , Animais , Bioensaio/economia , Bioensaio/métodos , Medição de Risco/economia , Medição de Risco/métodos , Testes de Toxicidade/economia , Testes de Toxicidade/métodosRESUMO
Two different concepts, termed concentration addition (CA) and independent action (IA), describe general relationships between the effects of single substances and their corresponding mixtures allowing calculation of an expected mixture toxicity on the basis of known toxicities of the mixture components. Both concepts are limited to cases in which all substances in a mixture influence the same experimental endpoint, and are usually tested against a "fixed ratio design" where the mixture ratio is kept constant throughout the studies and the overall concentration of the mixture is systematically varied. With this design, interaction among toxic components across different mixture ratios and endpoints (i.e. lethal versus sublethal) is not assessed. In this study lethal and sublethal (feeding) responses of Daphnia magna individuals to single and binary combinations of similarly and dissimilarly acting chemicals including the metals (cadmium, copper) and the pyrethroid insecticides (lambda-cyhalothrin and deltamethrin) were assayed using a composite experimental design to test for interactions among toxic components across mixture effect levels, mixture ratios, lethal and sublethal toxic effects. To account for inter-experiment response variability, in each binary mixture toxicity assay the toxicity of the individual mixture constituents was also assessed. Model adequacy was then evaluated comparing the slopes and elevations of predicted versus observed mixture toxicity curves with those estimated for the individual components. Model predictive abilities changed across endpoints. The IA concept was able to predict accurately mixture toxicities of dissimilarly acting chemicals for lethal responses, whereas the CA concept did so in three out of four pairings for feeding response, irrespective of the chemical mode of action. Interaction effects across mixture effect levels, evidenced by crossing slopes, were only observed for the binary mixture Cd and Cu for lethal effects. The analysis of regression residuals showed that interaction effects across mixture ratios were restricted to feeding responses in binary mixtures that included Cu. These results indicate that the ability of the CA and IA concept to predict mixture toxicity effects varies from lethal to sublethal endpoints irrespective of their primary mode of action. This suggests that when considering complex responses, the pharmacological notion of mode of action should be extended to encompass an ecotoxicological mode of action, based on the concentration at which various toxicological effects become operative in the biological system under consideration.
Assuntos
Cádmio/toxicidade , Cobre/toxicidade , Daphnia/efeitos dos fármacos , Inseticidas/toxicidade , Nitrilas/toxicidade , Piretrinas/toxicidade , Animais , Bioensaio/normas , Bioensaio/veterinária , Combinação de Medicamentos , Comportamento Alimentar/efeitos dos fármacos , Dose Letal Mediana , Modelos Lineares , Modelos Biológicos , Medição de Risco/normas , Medição de Risco/estatística & dados numéricos , Análise de Sobrevida , Testes de Toxicidade/normas , Testes de Toxicidade/veterináriaAssuntos
Fibroblastos/efeitos dos fármacos , Resíduos Industriais/efeitos adversos , Oncorhynchus , Curtume , Testes de Toxicidade/métodos , Poluentes Químicos da Água/toxicidade , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Carvão Vegetal/química , Relação Dose-Resposta a Droga , Monitoramento Ambiental/métodos , Feminino , Fibroblastos/patologia , Gônadas/citologia , Resíduos Industriais/análise , Masculino , Gerenciamento de Resíduos/métodos , Poluentes Químicos da Água/análiseRESUMO
Factors associated with residual insulin secretion and spontaneous remission in Type 1 diabetic patients are important in the evaluation of treatment aimed at modifying the natural history of Type 1 DM. We investigated the effect of parameters at onset on residual beta cell function in 215 Type 1 DM children and adolescents. Blood gas analysis, HLA, GAD and IA-2 antibodies before the start of insulin treatment were recorded for each patient. Residual C-peptide secretion was assessed by the glucagon test, and parameters of metabolic control (HbA1c and insulin dose U kg(-1) day(-1)) were examined at disease onset and after 3, 6, and 12 months. Residual C-peptide secretion throughout the first year of disease was significantly reduced in patients with disease onset before age 5. Multiple regression analysis showed that low pH at onset showed a significant and independent association with reduced C-peptide at 3 months (p = 0.02) and that the detection of GAD antibodies had a significant independent association with decreased C-peptide secretion at 6 months of follow-up (p = 0.02). Insulin requirement was higher in the youngest patients group and in patients with GAD antibodies. Spontaneous insulin remission (HbA1c <6% and insulin <0.3 U kg(-1) day(-1)) occurred in 22/192 (11%) patients at 3 months of follow-up, in 15/190 (8%) patients at 6 months and in 8/169 (5%) patient at 12 months. Remission was more prevalent in older patients (p = 0.01) and in patients without detectable GAD antibodies: (14/64 vs 8/128, p = 0.001). Sex, IA-2 antibodies and HLA DR were not independently associated with C-peptide secretion, insulin requirement or remission in the first year of Type 1 DM. This study confirms the association of young age, severe acidosis at disease onset, and GAD antibodies with decreased residual beta-cell function and spontaneous remission during the first year of insulin treatment. These factors should be considered in trials evaluating therapies to retain beta-cell function and induce remission at and after disease onset.
Assuntos
Diabetes Mellitus Tipo 1/sangue , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Proteínas de Membrana , Adolescente , Adulto , Especificidade de Anticorpos/imunologia , Autoanticorpos/imunologia , Autoantígenos/imunologia , Proteína C-Reativa/metabolismo , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Feminino , Glutamato Descarboxilase/imunologia , Hemoglobinas Glicadas/metabolismo , Antígenos HLA-DR/imunologia , Humanos , Hipoglicemiantes/uso terapêutico , Lactente , Insulina/imunologia , Insulina/uso terapêutico , Secreção de Insulina , Ilhotas Pancreáticas/imunologia , Masculino , Glicoproteínas de Membrana/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteínas Tirosina Fosfatases/imunologia , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores , Remissão Espontânea , Estudos RetrospectivosRESUMO
To investigate the role of puberty on spontaneous clinical remission and on secretion of residual C-peptide during the first year of type 1 diabetes mellitus, we studied 77 pre-pubertal, 39 pubertal and 41 post-pubertal type 1 diabetic patients. Spontaneous partial clinical remission (HbA1c within the normal range and insulin dose less than 0.3 U x kg(-1) body weight x day(-1) lasting for at least 10 days) decreased with duration of diabetes: months 3 vs 6 vs 12, respectively 13 vs 7 vs 4% (P<0.025). Remission was higher in post-pubertal than pubertal and prepubertal patients: month 6 respectively 20 vs 5 vs 1% (P<0.001). Secretion of C-peptide was significantly lower in pre-pubertal than the other two groups of patients. Basal and stimulated C-peptide secretion were higher in patients in clinical remission than in those who were not: basal value 0.4 (0.26-0.53) vs 0.28 (0.14-0.4) nmol/l (P<0.05); stimulated value 0.63 (0.5-0.95) vs 0.56 (0.31-0.74) nmol/l (P<0.05). Spontaneous remission is less frequent in children and adolescent patients than in adult post-pubertal patients, but different mechanisms may be involved. Low residual insulin secretion seems implicated in children meanwhile low insulin sensitivity could be more important in pubertal patients.
Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Ilhotas Pancreáticas/metabolismo , Puberdade/fisiologia , Adolescente , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Humanos , Insulina/administração & dosagem , Insulina/metabolismo , Insulina/uso terapêutico , Secreção de Insulina , Masculino , Remissão EspontâneaRESUMO
Rainbow trout, Oncorhynchus mykiss, were exposed to a sublethal dose of a wool shrinkproofing effluent for 15, 30, 45 and 60 days. Liver and blood samples were taken after the exposure time together with samples of control handled fish. A light and electron microscope study was carried out to evaluate the histopathological lesions induced in the liver of treated fish. The genotoxic potential of the effluent was assessed by piscine micronucleus test. Vacuolation of liver bile preductular cells was observed in all exposed fish; abnormal lipid accumulation and basophilic foci were seen in the liver of one 30-days- and 45-days-exposed fish, respectively. These specific alterations could be related to a pre-carcinogenic process. On the contrary, other lesions also described in all treated fish such as dilatation, vesiculation and degranulation of the rough endoplasmic reticulum, altered mitochondria, increase in myelin bodies and lysosomes and presence of phagosomes in wandering macrophages might be considered as non-specific alterations, similar to those described in fish exposed to different pollutants. Frequencies of micronucleated peripheral erythrocytes showed a significant increase following 30-days exposure.
Assuntos
Resíduos Industriais/efeitos adversos , Fígado/efeitos dos fármacos , Mutagênicos/toxicidade , Têxteis , Poluição Química da Água/efeitos adversos , Animais , Fígado/patologia , Fígado/ultraestrutura , Testes para Micronúcleos , Oncorhynchus mykiss , VacúolosRESUMO
OBJECTIVE: Height and weight changes during the first 3 years of diabetes were prospectively followed in 152 diabetic children and adolescents. RESEARCH DESIGN AND METHODS: The study sample consisted of 152 Caucasian diabetic patients (84 boys; 68 girls) followed from diabetes onset in the Paediatric Diabetes Unit and 80 Caucasian normal subjects (49 boys; 31 girls) assessed in the Outpatient General Paediatric Clinic of the same hospital for routine examination and not affected by problems that might influence growth. Diabetic patients and control subjects were consecutively enrolled in the study between 1989 and 1992; diabetic patients with positive markers for celiac disease (positive antiendomysial antibodies) and thyroid disease (positive antimicrosomial antibodies) or any other chronic disease were not considered in the study. Mean age of diabetic patients (8.9 +/- 4.1 years) and control subjects (8.5 +/- 4.2 years) at recruitment in the study was similar. RESULTS: At onset of diabetes, the mean height expressed as the height standard deviation score (HSDS) was significantly greater than the expected values (P < 0.0001) and was independent of sex and pubertal stage. During the first 3 years of diabetes, HSDS decreased significantly (F = 6.9; P < 0.001). Meanwhile, growth velocity as standard deviation score (SDS) decreased significantly between the 1st and 2nd year (-0.12 +/- 2.1; -0.76 +/- 2.6, respectively; P < 0.05), but it was similar between the 2nd and 3rd year of diabetes. Weight expressed as SDS increased significantly during the first 2 years of diabetes but not thereafter. Height changes during the study period were independent from pubertal stage and sex. Metabolic control and insulin requirement, in our series, were not clearly related to height and weight changes. CONCLUSIONS: Diabetic patients at onset of diabetes are taller than age- and sex-matched nondiabetic subjects. During the first years of the disease, linear growth decreases independently of metabolic control and weight changes.
Assuntos
Estatura , Peso Corporal , Diabetes Mellitus Tipo 1/fisiopatologia , Crescimento/fisiologia , Adolescente , Idade de Início , Criança , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Valores de Referência , Fatores de TempoRESUMO
Insulin-dependent diabetes mellitus is associated to important micro and macro vascular complications. A good metabolic control can reduce the risk of complications. Aim of the study was to evaluate the metabolic control in adolescent diabetic patients using an educational system with graphic visualisation of capillary glycaemia. 40 (22 males, 18 females) insulin-dependent diabetic patients (age: 16.9 +/- 3.5 yrs; duration of diabetes: 6.7 +/- 4.6 yrs) were divided in two groups matched for age, sex, duration of diabetes and metabolic control. Patients of group 1 used One Touch II Video for three months. One Touch II Video is an educational program for diabetes mellitus linked to a meter for glycaemia assessment. Patients of group 2 were used as control group. All data were expressed as a mean +/- SD and were analysed by parametric t-Student test. In group 1 HbA1c at the end of the study was significantly reduced compared to the initial value: 8.58 +/- 1.65% vs 7.9 +/- 1.0% (p < 0.05). In group 2 HbA1c at end of the study was no different from the initial value. At short term One Touch II Video could be a useful instrument to improve metabolic control in insulin-dependent diabetic adolescents.
Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Hipoglicemia/diagnóstico , Adolescente , Adulto , Feminino , Humanos , MasculinoRESUMO
The quantitative determination in organs of Oncorhynchus mykiss W. of a premetallized dye (C.I. Acid Violet 66) and the azoic base (C.I. Acid Red 217), used in wool dyeing, is studied in this paper. UV-VIS Spectrophotometry was used for the chromatic quantification and atomic absorption spectrophotometry for the detection of the metal. The method described here is as satisfactory for the detection of some commercial dyes as the methods developed by ETAD (Ecological and Toxicological Association of the Dyestuffs Manufacturing Industry).