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1.
J Intern Med ; 284(6): 674-684, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29974534

RESUMO

BACKGROUND: Familial hypercholesterolemia could be prevalent among patients with acute coronary syndrome. OBJECTIVE: To investigate both the frequency of causative mutations for familial hypercholesterolemia (FH) and the optimal selection of patients for genetic testing among patients with an acute coronary syndrome (ACS). METHODS: One hundred and sixteen patients with an ACS during 2009-2015 were identified through the SWEDEHEART registry. Patients who had either a high total cholesterol level ≥7 mmol L-1 combined with a triglyceride level ≤2.6 mmol L-1 , or were treated with lipid-lowering medication and had a total cholesterol level >4.9 mmol L-1 and a triglyceride level ≤2.6 mmol L-1 were included. Genetic testing was performed first with a regionally designed FH mutation panel (118 mutations), followed by testing with a commercially available FH genetic analysis (Progenika Biopharma). RESULTS: A total of 6.9% (8/116) patients had a FH-causative mutation, all in the LDL-receptor. Five patients were detected on the panel, and further testing of the remaining 111 patients detected an additional 3 FH-causative mutations. Baseline characteristics were similar in FH-positive and FH-negative patients with respect to age, gender, prior ACS and diabetes. Patients with a FH-causative mutation had higher Dutch Lipid Clinical Network (DLCN) score (5.5 (5.0-6.5) vs 3.0 (2.0-5.0), P < 0.001) and a higher low-density lipoprotein level (5.7 (4.7-6.5) vs 4.9 (3.5-5.4), P = 0.030). The Dutch Lipid Clinical Network (DLCN) score had a good discrimination with an area under the curve of 0.856 (95% CI 0.763-0.949). CONCLUSION: Genetic testing for FH should be considered in patients with ACS and high DLCN score.


Assuntos
Síndrome Coronariana Aguda/genética , Ácidos Cólicos/sangue , Testes Genéticos , Erros Inatos do Metabolismo de Esteroides/genética , Síndrome Coronariana Aguda/etiologia , Idoso , Colesterol/sangue , Ácidos Cólicos/genética , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Erros Inatos do Metabolismo de Esteroides/complicações , Sobreviventes , Triglicerídeos/sangue
2.
Allergy ; 70(2): 241-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25413686

RESUMO

The reports on atopic diseases and microbiota in early childhood remain contradictory, and both decreased and increased microbiota diversity have been associated with atopic eczema. In this study, the intestinal microbiota signatures associated with the severity of eczema in 6-month-old infants were characterized. Further, the changes in intestinal microbiota composition related to the improvement of this disease 3 months later were assessed. The severity of eczema correlated inversely with microbiota diversity (r = -0.54, P = 0.002) and with the abundance of butyrate-producing bacteria (r = -0.52, P = 0.005). During the 3-month follow-up, microbiota diversity increased (P < 0.001) and scoring atopic dermatitis values decreased (P < 0.001) in all infants. This decrease coincided with the increase in bacteria related to butyrate-producing Coprococcus eutactus (r = -0.59, P = 0.02). In conclusion, the high diversity of microbiota and high abundance of butyrate-producing bacteria were associated with milder eczema, thus suggesting they have a role in alleviating symptoms of atopic eczema.


Assuntos
Bactérias/metabolismo , Butiratos/metabolismo , Hipersensibilidade Imediata/diagnóstico , Hipersensibilidade Imediata/etiologia , Intestinos/microbiologia , Microbiota , Biodiversidade , Dermatite Atópica/diagnóstico , Dermatite Atópica/etiologia , Eczema/diagnóstico , Eczema/etiologia , Seguimentos , Humanos , Lactente , Índice de Gravidade de Doença
3.
Nurs Ethics ; 6(4): 278-86, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10696176

RESUMO

This article investigates whether or not an ethical attitude manifests itself in the clinical supervision of nursing students. The data consist of 57 narratives written by nursing students, which were subjected to latent content analysis. The interpretation represents a caring science perspective based on Eriksson's 'caring ethics'. The results showed that some students received good supervision, while others felt hurt and humiliated. The students were of the opinion that they should feel welcome, be allowed to take responsibility and be treated as individuals by their supervisors. Supervision can take a form such that the ethical element comes to the fore in the conduct of the students as well as of their supervisor. Both the students' and the supervisor's disposition permeates all the questions, actions and reflections that form part of supervision, which could help to bring students' ethical sense to maturity.


Assuntos
Atitude do Pessoal de Saúde , Ética em Enfermagem , Supervisão de Enfermagem/organização & administração , Estudantes de Enfermagem/psicologia , Empatia , Feminino , Humanos , Relações Interprofissionais , Descrição de Cargo , Masculino , Pesquisa Metodológica em Enfermagem , Competência Profissional , Pesquisa Qualitativa , Pesquisa , Inquéritos e Questionários
4.
Mutagenesis ; 12(5): 339-45, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9379912

RESUMO

Three metabolites of 1,3-butadiene, namely butadiene diolepoxide, butadiene monoepoxide and diepoxybutane, were tested in the bacterial mutation assay using Salmonella typhimurium strain TA100 with and without metabolic activation (S9 mix). All three compounds showed a mutagenic response. The bifunctional epoxide was more effective than the diolepoxide which was more effective than the monoepoxide. Toxicity appeared to follow the ranking of the chemicals for their mutagenic potency. The monoepoxide and the diolepoxide were also tested for induction of micronuclei in mouse bone marrow erythrocytes and for dominant lethal mutation induction in postmeiotic male mouse germ cells. The effects of the diepoxide in both in vivo tests have been published earlier. In the micronucleus assay, the three metabolites gave a positive response whereby the diepoxide was more effective than the monoepoxide which was more effective than the diolepoxide. In contrast to the diepoxide which was positive at a dose as low as 36 mg/kg, the monoepoxide and the diol did not show an induction of dominant lethal effects up to doses of 120 and 240 mg/kg, respectively. It is concluded that the metabolites were mutagenic in bacteria without metabolic activation and clastogenic in mouse bone marrow; only the bifunctional diepoxide, however, was active in postmeiotic male mouse germ cells.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Compostos de Epóxi/farmacologia , Compostos de Epóxi/toxicidade , Glicóis/farmacologia , Glicóis/toxicidade , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Mutagênicos/toxicidade , Animais , Células da Medula Óssea/patologia , Butadienos , Cruzamentos Genéticos , Feminino , Morte Fetal , Genes Letais , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos , Testes para Micronúcleos , Testes de Mutagenicidade , Gravidez , Salmonella typhimurium/efeitos dos fármacos , Relação Estrutura-Atividade
5.
Carcinogenesis ; 18(4): 817-23, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9111220

RESUMO

Benzene is a well-characterized human carcinogen and clastogen still present in both the occupational and general environment. However, the levels of benzene encountered today are, in most cases, relatively low and new methods, more specific and sensitive than classical cytogenetics, are probably needed to assess if current benzene exposures pose a genotoxic risk to human health. Bearing in mind the leukaemogenic action of benzene, blood lymphocytes appear to be a suitable cell system for biomonitoring studies. Buccal epithelium is an alternative source of tissue for monitoring human exposure to inhaled occupational and environmental genotoxicants. New molecular cytogenetic techniques allowing us to specifically study clastogenic or aneugenic events in human cells may provide the additional sensitivity required. In the present study, fluorescence in situ hybridization was used to examine the content of micronuclei (MN) (using the pan-centromeric DNA probe SO-alphaAllCen) in lymphocytes and buccal cells and to detect numerical abnormalities of chromosome 9 (using a chromosome 9 centromere-specific alphoid DNA probe) in buccal cells from a population occupationally exposed to benzene in an Estonian petrochemical plant. Age-matched Estonian volunteers were used as a control group. Individual benzene exposure levels were estimated to be around 1 p.p.m. (8 h time-weighted average). No increases in the frequency of total MN, MN harbouring whole chromosomes or acentric chromosomal fragments or chromosome 9 numerical abnormalities were detected in relation to benzene exposure in the present study. The lack of positive results was consistent in both buccal cells and lymphocytes, indicating that the benzene exposure levels encountered did not induce detectable clastogenic or aneugenic effects in the exposed workers. Other variables and confounding factors, such as age, smoking or alcohol consumption, did not influence any of the multiple cytogenetic biomarkers analysed.


Assuntos
Benzeno/toxicidade , Linfócitos/efeitos dos fármacos , Mucosa Bucal/efeitos dos fármacos , Mutagênicos/toxicidade , Exposição Ocupacional , Bochecha , Aberrações Cromossômicas , Cromossomos Humanos Par 9 , Humanos , Linfócitos/ultraestrutura , Testes para Micronúcleos , Mucosa Bucal/ultraestrutura
6.
Acta Obstet Gynecol Scand ; 75(2): 149-56, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8604602

RESUMO

BACKGROUND: Our aims were to elucidate whether a decreased fertility in smoking women treated by in vitro fertilization (IVF) could be related to a divergent hormonal response to the controlled stimulation prior to IVF, to study the effect of smoking on the ovarian endocrine milieu and to possibly identify factors that might be detrimental to oocyte fertilization. METHODS: Serum and follicular fluid concentrations of estradiol-17 beta (E2), progesterone (P), testosterone (T), 4-androstene-3,17-dione (A-4), dehydroepiandrosterone (DHA), DHA sulfate (DHAS), sex hormone-binding globulin (SHBG) and serum cortisol were studied in 50 non-smoking and 50 smoking women in an IVF program. Follicular fluid concentrations were also compared in follicles which gave rise to cleaved oocytes (TYPE I) and follicles which failed to yield fertilized oocytes (TYPE II) in the same woman. RESULTS: The fertilization rate did not differ significantly between the two groups, but the live birth rate was 30% in non-smokers and 4% in smokers. During treatment, serum A-4, DHAS and the T/SHBG-ratio were significantly higher in smokers than in non-smokers. In the TYPE I follicles, smokers had higher follicular fluid concentrations of A-4 and DHA and a higher E2/P ratio. The TYPE II follicles in smokers had higher A-4 and T and lower E2 levels. CONCLUSIONS: Smoking women have a relative hyperandrogenism of ovarian origin, which may contribute to the lower pregnancy rate at IVF in this group.


Assuntos
Fertilidade/fisiologia , Fertilização in vitro/normas , Hiperandrogenismo/etiologia , Hiperandrogenismo/fisiopatologia , Taxa de Gravidez , Fumar/efeitos adversos , Adulto , Análise de Variância , Androstenodiona/análise , Androstenodiona/sangue , Desidroepiandrosterona/análise , Desidroepiandrosterona/sangue , Estradiol/análise , Estradiol/sangue , Feminino , Líquido Folicular/química , Humanos , Hidrocortisona/análise , Hidrocortisona/sangue , Oócitos/citologia , Oócitos/fisiologia , Folículo Ovariano/citologia , Folículo Ovariano/fisiologia , Gravidez , Progesterona/análise , Progesterona/sangue , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/análise , Testosterona/sangue
8.
Ultrasound Obstet Gynecol ; 4(6): 476-9, 1994 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-12797128

RESUMO

The Doppler flow velocity pulsatility index (PI) of the uteroplacental vascular bed is of debatable value for the interpretation of hemodynamic changes, when these are due both to pathological alterations in the vasculature, as in mild pre-eclampsia, and to physiological adjustments to vasoactive substances. The aim of this study was to apply a mathematical model, which includes maternal pulse pressure and mean arterial pressure, to the PI and to investigate whether this formula would add information with respect to discrimination between normal women and those with mild or severe pre-eclampsia. The subjects were patients with mild (n = 41) and severe (n = 34) pre-eclampsia and, as a control group, healthy pregnant women (n = 46). The uterine artery PI was studied by spectral Doppler analyses and compared to a P(z) value, theoretically representing a 'back pressure' in the uteroplacental circulation. Additionally, P(z) values were computed from earlier data concerning the dynamic circulatory effects of dihydralazine and acute volume expansion. The basal PI was significantly higher in the severely pre-eclamptic patients but not in the mildly pre-eclamptic patients compared to the controls. However, the P(z) was significantly higher in patients with both mild (p < 0.001) and severe pre-eclampsia (p < 0.0001) compared to the normal group. In the severely pre-eclamptic patients receiving dihydralazine, the P(z) tended to decrease (p = 0.07), in contrast to the volume-expansion group where P(z) was unaffected by the procedure. In conclusion, it seems that including measurement of the mean arterial pressure and pulse pressure with the PI adds valuable information about the circulatory status in this particular vasculature, regarding both 'basal' values and hemodynamic changes.

10.
Obstet Gynecol ; 84(2): 235-9, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8041537

RESUMO

OBJECTIVE: To study the effects of low doses of the hormone atrial natriuretic peptide (ANP) on uteroplacental blood flow in patients with preeclampsia. METHODS: Eleven women with preeclampsia were infused intravenously with ANP (10 ng/kg/minute). Uteroplacental blood flow index was measured using dynamic placental scintigraphy with indium-113m. Regional blood flows were assessed by pulsed Doppler ultrasound and expressed as pulsatility index (PI). Hemodynamic measurements and blood sampling for peripheral venous plasma analysis of cyclic guanosine monophosphate (cGMP), an ANP second messenger, were performed before and after 30 minutes of infusion. Nonparametric statistics were used. RESULTS: The uteroplacental blood flow index increased by 28% (-2 to 58%; mean and 95% confidence interval). The Doppler findings were unaffected. Mean arterial blood pressure decreased from 112 (108-117) to 108 (103-114) mmHg (P < .01). Cyclic GMP increased significantly from 9.2 (6.2-12.3) to 17.4 (12.3-22.6) nmol/L (P < .01). Subjects exhibiting a substantial increase in uteroplacental blood flow index (25% or more) demonstrated a significantly greater cGMP response (P < .01) than those who did not (6% or less increase). CONCLUSION: A tendency to an increased uteroplacental blood flow index combined with minor blood pressure reduction after ANP infusion suggest the possibility of uteroplacental vasodilatation.


Assuntos
Fator Natriurético Atrial/administração & dosagem , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Troca Materno-Fetal/efeitos dos fármacos , Pré-Eclâmpsia/tratamento farmacológico , Vasodilatação/efeitos dos fármacos , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Feminino , Guanosina Monofosfato/sangue , Humanos , Radioisótopos de Índio , Infusões Intravenosas , Troca Materno-Fetal/fisiologia , Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/fisiopatologia , Gravidez , Fluxo Pulsátil , Cintilografia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Ultrassonografia Pré-Natal , Útero/irrigação sanguínea , Útero/diagnóstico por imagem , Vasodilatação/fisiologia
11.
Paraplegia ; 32(7): 463-7, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7970847

RESUMO

Infertility due to spinal cord injury (SCI) in males has been identified for decades as an area of major concern and techniques for assisted ejaculation are available. There has not been an overall consensus regarding which type of assisted procreation is the most appropriate for these couples. We describe here our experience from a programme based on assisted ejaculation combined with in vitro fertilization (IVF). Twelve couples have been treated so far and altogether 22 cycles with ovum pick-up have been completed. Fertilisation of the oocytes was obtained in 18 of these cycles. The overall oocyte fertilisation rate was 49%. Embryo transfer took place in 17 cycles, leading to seven clinical pregnancies. Four of the pregnancies are delivered or are ongoing, whereas three ended in first trimester spontaneous abortion. Thus our initial experience suggests that assisted ejaculation in combination with IVF is an effective option for these couples.


Assuntos
Ejaculação , Fertilização in vitro , Infertilidade Masculina/terapia , Traumatismos da Medula Espinal/complicações , Adulto , Busserrelina/uso terapêutico , Ejaculação/efeitos dos fármacos , Feminino , Humanos , Infertilidade Masculina/etiologia , Masculino , Pessoa de Meia-Idade , Nafarelina/uso terapêutico , Estimulação Física , Fisostigmina/farmacologia , Gravidez , Vibração
12.
Am J Perinatol ; 11(3): 231-6, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8048992

RESUMO

Strict blood glucose control of pregnant women with insulin-dependent diabetes is associated with increased risk of hypoglycemia. The hormonal and circulatory responses to an acute episode of insulin-induced hypoglycemia were studied in eight pregestational and one gestational diabetic women during the last trimester of pregnancy and 8 to 12 weeks postpartum. Following an overnight fast, insulin was injected intravenously (0.1 to 0.2 IU insulin/kg). Blood samples were taken at -15, 0, 15, 30, 40, 60, 90, and 120 minutes for analyses of metabolites (glucose, nonesterified fatty acid (NEFA), glycerol, 3-hydroxybutyrate) and counterregulatory hormones (epinephrine, norepinephrine, glucagon, and cortisol). Placental scintigraphy (indium-113m) was performed in five pregnant patients before and during hypoglycemia. Both during pregnancy and postpartum, blood glucose decreased to the same low level (3.2 mmol/L) concomitantly with significant decreases in NEFA, glycerol, and 3-hydroxybutyrate. Epinephrine and norepinephrine showed significant and similar increases on both occasions in relation to hypoglycemia, although there was no response in glucagon and cortisol concentrations. Maternal heart rate was significantly higher in the pregnant compared with the nonpregnant state and increased significantly in both groups in response to hypoglycemia. Placental blood flow showed no consistent changes and was unrelated to the glucose and catecholamine responses. Fetal heart rate remained unchanged. Thus, it seems as if hormonal and circulatory responses to acute hypoglycemia are not altered in diabetic women during pregnancy.


Assuntos
Circulação Sanguínea , Catecolaminas/sangue , Diabetes Mellitus Tipo 1/complicações , Hipoglicemia/fisiopatologia , Lipídeos/sangue , Gravidez em Diabéticas/fisiopatologia , Ácido 3-Hidroxibutírico , Adulto , Glicemia/metabolismo , Pressão Sanguínea , Diabetes Mellitus Tipo 1/fisiopatologia , Epinefrina/sangue , Ácidos Graxos não Esterificados/sangue , Feminino , Glucagon/sangue , Glicerol/sangue , Frequência Cardíaca , Humanos , Hidrocortisona/sangue , Hidroxibutiratos/sangue , Hipoglicemia/induzido quimicamente , Insulina/efeitos adversos , Norepinefrina/sangue , Gravidez , Terceiro Trimestre da Gravidez
13.
Carcinogenesis ; 15(5): 813-5, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8200080

RESUMO

We examined the genotypes of two polymorphic genes involved in the detoxification of several mutagenic and carcinogenic compounds in relation to tobacco smoking-associated urinary mutagenicity. The genes studied were the glutathione S-transferase-encoding GSTM1 gene and acetyltransferase-encoding NAT2 gene. Smokers with no GSTM1 gene (n = 7) had urine that was several times more mutagenic than that of smokers with the gene (n = 10). The mean level of urinary mutagenicity in presence of metabolic activation was 2527 +/- 958 revertants/100 ml urine for GSTM1-smokers compared to 766 +/- 560 revertants/100 ml for GSTM1+ smokers (P < 0.001) using the bacterial strain YG1024. The corresponding values using the TA98 strain were 336 +/- 124 and 123 +/- 75 (P < 0.001). In contrast, we failed to show any difference in the level of urinary mutagenicity between slow-acetylator and fast-acetylator NAT2 genotypes among smokers (n = 17) or non-smokers (n = 35). Our results offer one explanation for the recent findings that GSTM1 polymorphism is a risk modifier in smoking-related cancers, especially bladder cancer.


Assuntos
Arilamina N-Acetiltransferase/genética , Carcinógenos/metabolismo , Carcinógenos/toxicidade , Glutationa Transferase/genética , Mutagênicos/metabolismo , Mutagênicos/toxicidade , Fumar/genética , Fumar/urina , Biotransformação , Carcinógenos/farmacocinética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Mutagenicidade , Mutagênicos/farmacocinética
14.
Acta Obstet Gynecol Scand ; 73(4): 294-9, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8160534

RESUMO

OBJECTIVE: To compare normal pregnancy with pregnancy-induced hypertension (PIH)/preeclampsia with respect to the effects of acute volume expansion on plasma atrial natriuretic peptide (ANP), cyclic guanosine monophosphate (cGMP) and fetal-maternal circulation. DESIGN: Observational study. SETTING: University hospital. SUBJECTS: Fifteen women with PIH/preeclampsia and 15 healthy pregnant controls. INTERVENTIONS: Before and after 30 minutes' infusion of a crystalloid solution (15 ml/kg), maternal venous blood was sampled for ANP and cGMP analysis and echocardiographic and Doppler investigations were performed. RESULTS: Basal median (range) ANP and cGMP levels were significantly higher in the PIH/preeclampsia group compared to the controls: 6.5 (3.8-30.4) compared to 3.9 (2.0-6.7) pmol/l, p < 0.01 and 5.8 (2.4-11.6) compared to 4.0 (2.3-10.8) nmol/l, p < 0.05. The response to volume load was enhanced: 4.6 (-4.5-21.8) compared to 0.7 (-4.1-8.8), p < 0.05 and 2.9 (0.1-10.9) compared to 1.2 (-5.0-6.0), p < 0.05, respectively. Systemic vascular resistance was initially higher in the patient group, 22.3 (14.1-36.7) compared to 15.6 (10.0-25.5) peripheral resistance units, p < 0.01 but the response to volume load was similar in both groups (12-13% decrease). The pulsatility index of the uterine artery, 0.85 (0.46-1.38) compared to 0.72 (0.49-1.26) and umbilical artery 0.89 (0.66-1.57) compared to 0.97 (0.74-1.31) did not differ between the groups. Volume expansion did not affect any of these variables. CONCLUSIONS: The pulsatility index of the uterine artery remained unaffected in both preeclamptic patients and healthy controls despite an increase of ANP and cGMP concentration and a systemic vasodilatation during acute volume expansion. This finding may indicate the absence of a vasodilation of the uteroplacental vascular bed.


Assuntos
Fator Natriurético Atrial/sangue , GMP Cíclico/sangue , Pré-Eclâmpsia/sangue , Gravidez/sangue , Circulação Sanguínea , Volume Sanguíneo , Feminino , Sangue Fetal/química , Humanos , Hipertensão Renal/sangue , Troca Materno-Fetal , Terceiro Trimestre da Gravidez , Fluxo Pulsátil , Resistência Vascular
16.
Mutat Res ; 320(3): 165-74, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7508082

RESUMO

The genotoxicity of spent liquors from kraft softwood and hardwood pulp bleaching processes was studied using the Ames Salmonella test and the SOS chromotest. The induction of micronuclei, in vivo, was assayed in bone marrow erythrocytes of B6 mice treated with softwood first chlorination stage spent liquor. The softwood bleaching process used a combination of Cl2 and ClO2 at the first chlorination stage. During the study the amount of free chlorine at the first chlorination stage in the softwood bleachery was gradually decreased, although the amount of active chlorine remained the same. Enzymatic bleaching was also used in a softwood process together with chlorine (Cl2 + ClO2). The hardwood bleaching plant used only ClO2 at the first chlorination stage. A decrease in genotoxicity, corresponding to the decrease in Cl2, was observed in the Ames Salmonella assays of the softwood bleaching plant effluents. A similar decrease was observed in the SOS chromotest. The highest decrease in mutagenic activity was observed when enzymatic bleaching was used together with chlorine.


Assuntos
Resíduos Industriais , Mutagênicos/toxicidade , Papel , Madeira , Animais , Biotransformação , Medula Óssea/efeitos dos fármacos , Medula Óssea/ultraestrutura , Cloro , Camundongos , Testes de Mutagenicidade , Mutagênicos/farmacocinética , Resposta SOS em Genética , Salmonella typhimurium/genética
17.
Mutat Res ; 300(1): 37-43, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7683766

RESUMO

Cotinine concentrations in amniotic fluid samples from 22 smoking and 37 non-smoking pregnant women and induction of sister-chromatid exchanges (SCE) in Chinese hamster ovary (CHO) cells by samples from 15 smokers and 15 non-smokers were studied as indicators of exposure to potential genotoxic activity during pregnancy. Analysis of cotinine revealed one individual in the non-smoking group with a high cotinine level apparently due to non-reported smoking. The mean cotinine concentration of smokers was 85 ng/ml whereas non-smokers had a concentration of 0.3 ng/ml. According to interview data 16 persons announced some passive exposure to tobacco smoke at home or at work; however this group did not differ from unexposed non-smokers in their amniotic fluid cotinine concentration. SCE inducing activity was tested with and without metabolic activation. The mean SCE frequency in CHO cells induced in the presence of exogenous metabolic activation by concentrated amniotic fluid of heavy smokers (> or = 10 cigarettes/day) was significantly higher (9.7 +/- 0.6 SCE/cell) than among non-smokers (8.9 +/- 0.6 SCE/cell) with metabolic activation. The results show that amniotic fluid cotinine measurements and induction of SCEs in CHO cells can be used to indicate fetal exposure by maternal smoking and support earlier studies suggesting a potential genotoxic hazard to the fetus of heavy smokers.


Assuntos
Líquido Amniótico/química , Cotinina/análise , Gravidez , Troca de Cromátide Irmã , Fumar , Adulto , Amniocentese , Animais , Células CHO , Cricetinae , Cricetulus , Feminino , Humanos , Testes de Mutagenicidade , Segundo Trimestre da Gravidez
19.
Mutat Res ; 272(3): 205-14, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1281266

RESUMO

Mutagenicity testing of biological samples and proteins is complicated by the presence of histidine and histidine-related growth factors which may produce a false positive result in the Ames/Salmonella plate incorporation test. A bioassay method, utilizing an automated dispenser-photometer and Salmonella typhimurium strain TA1535 as the indicator bacteria, was used to estimate the presence of histidine-related growth factors in three enzyme solutions submitted for mutagenicity testing. One of the solutions was clearly positive in the Ames/Salmonella test and also contained the highest amount of L-histidine-HCl-equivalents. The two other solutions, with low or undetectable amounts of L-histidine-HCl-equivalents, gave equivocal and negative results, respectively, in the Ames/Salmonella test. Studies were also performed with strains TA98, TA100 and TA1535 to determine the amount of added L-histidine-HCl that would result in a 'positive' result in the Ames/Salmonella test. Because the minimum amount of L-histidine-HCl required to double the number of revertant colonies was 150 nmol/plate, and the maximum amount of L-histidine-HCl-equivalents supplied by the enzyme preparations was 40 nmol/plate at the highest tested dose, the mutagenicity test results of the enzyme solutions cannot be explained solely by histidine or related compounds. Smokers' and non-smokers' urines, concentrated with liquid extraction (CHCl3) and adsorbent (XAD-2 and XAD-2/Sep-Pak C18) techniques, were studied to reveal differences in efficiencies to extract histidine and histidine-related compounds in the urines. Amounts of 'histidine' in concentrates of urine were measured using the bioassay method and a chemical method employing derivatization with fluorescamine. The fluorescamine method also efficiently detected 3-methyl-L-histidine, a product of muscle metabolism excreted in urine, which was found to be unable to support auxotrophic growth in TA1535, leading to exaggerated estimations of the auxotrophic growth enhancing properties of urine extracts. The urine extracts, and pure L-histidine-HCl, were tested using a two-step fluctuation test to estimate auxotrophic growth factor effects in this type of test. Because of a strong dilution effect when adding the histidine-free selection medium, the fluctuation test employed in this study was not found to be particularly sensitive to growth factors. The results of this study indicate that use of a bioassay, employing the same indicator bacteria as the mutagenicity test themselves, is a reliable way to measure histidine-related growth factors in biological samples.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Enzimas/química , Histidina/análise , Testes de Mutagenicidade/métodos , Enzimas/toxicidade , Reações Falso-Positivas , Fluorescamina , Histidina/urina , Humanos , Cinética , Masculino , Salmonella typhimurium , Fumar
20.
Hum Reprod ; 7(7): 918-21, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1430128

RESUMO

Serum concentrations of testosterone, 4-androstene-3,17-dione (androstenedione), dehydroepiandrosterone (DHA) and its sulphate and sex hormone-binding globulin (SHBG) were measured in 30 ovulatory women before and after down-regulation with gonadotrophin releasing-hormone analogue, prior to ovarian stimulation in a programme of in-vitro fertilization and embryo transfer. Nine of the women developed ovarian hyperstimulation syndrome (OHSS) while the others did not. Pretreatment values of androstenedione and the androstenedione:DHA ratios were higher and the testosterone:androstenedione ratios lower in the OHSS women. The decrease in androstenedione levels during down-regulation was greater and the absolute levels following down-regulation were lower in the OHSS group. Higher levels of SHBG and lower testosterone:SHBG ratios, an index of biologically active testosterone, were observed in the OHSS group. The isolated elevation in pretreatment androstenedione levels and the high SHBG levels make the OHSS group different from patients with polycystic ovarian disease. Pretreatment values of testosterone:androstenedione or testosterone/SHBG:androstenedione ratios and/or the decrease in androstenedione during down-regulation may be used as markers, prior to stimulation, for identifying women at risk of developing OHSS.


Assuntos
Androstenodiona/sangue , Síndrome de Hiperestimulação Ovariana/sangue , Adulto , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona , Feminino , Homeostase/fisiologia , Humanos , Síndrome de Hiperestimulação Ovariana/etiologia , Indução da Ovulação/efeitos adversos , Valor Preditivo dos Testes , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue
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