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51.
Marcos Barbosa-Ferreira Maria Lúcia Zaidan Dagli Paulo César Maiorka Silvana Lima Górniak 《Food and chemical toxicology》2005,43(4):497-503
Senna occidentalis (So) is a weed that grows in pastures along fences and in fields cultivated with cereals such as corn and soybean, and many reports have been showing intoxication with this plant in different animal species. It is also used in many medicinal purposes. The objective of the present study was to better evaluate the toxic effects of prolonged administration of So seeds to rats. Forty male Wistar rats were divided into four groups of 10 animals each, three of them respectively fed rations containing 1%, 2% and 4% So seeds, and the last one (control) fed commercial ration for a period of 2 weeks. Fourteen rats were also used in a pair-feeding (PF) experiment. The rats of the experimental groups showed lethargy, weakness, recumbency, depression and emaciation. Two rats of the 4% group and two of the PF group died during the experiment. Histopathological study showed fiber degenerations in the skeletal (Tibial, pectoral and diaphragm) and cardiac muscles. In the liver parenchyma, was observed vacuolar degeneration and, in the kidney, mild nefrosis in the proximal convoluted tubules. All of these alterations occurred in a dose-dependent fashion. Moderate to severe degeneration and spongiosis in the central nervous system, especially in cerebellum. Electron microscopy revealed mitochondrial lesions in all analyzed tissues. 相似文献
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This study compared the frequency of factors and diseases that contribute to the risks of oral contraceptive use among current users and non-users of oral contraception in order to evaluate the users' awareness of factors associated with complications during oral contraceptive use. Data from 5317 current users and 8863 non-users in the state of São Paulo, Brazil, were collected using questionnaires requesting information on the following variables: use of oral contraceptives, age, weight, smoking status, and the presence or history of hypertension, diabetes, cardiopathies, painful varicose veins, and epilepsy. Half of the users had some risk factors, and 17.4% were at high risk of complications from oral contraceptive use. Risk factors and diseases which appeared to be poorly known by the population as increasing the risk of oral contraceptive use were smoking, hypertension and painful varicose veins. Only a small percentage of the population appeared to know that these diseases and factors could increase the risk of health problems during oral contraceptive use. The results suggest a lack of information among users and providers on factors which are associated with an increased risk of health problems during use of oral contraceptives.
Resumen Este estudio comparó la frecuencia de factores y enfermedades que contribuyen al riesgo de los anticonceptivos orales (AO) entre usuarias y no usuarias corrientes de anticonceptivos orales a fin de evaluar el grado de conocimiento entre las usuarias de los factores asociados con complicaciones durante el uso de AO. Se recopilaron datos de 5317 usuarias y 8863 no usuarias corrientes del Estado de S@o Paulo, Brasil, utilizando cuestionarios en los que se solicitabe información acerca de las siguientes variables: uso de AO, edad, peso, fumadora/no fumadora y la presencia o historia de hipertensión, diabetes, cardiopatías, várices dolorosas y epilepsia. La mitad de las usuarias tenían algunos factores de riesgo y el 17,4% de ellas corrían un alto riesgo de complicaciones por el uso de anticonceptivos orales. Los factores de riesgo y enfermedades que parecían ser poco conocidos por la población como tendientes a aumentar el riesgo del uso de anticonceptivos orales eran el fumar, la hipertensión y las várices dolorosas. Sólo un pequeño porcentaje de la población parecía saber que estas enfermedades y factores podían aumentar el riesgo de problemas de salud durante el uso de anticonceptivos orales. Los resultados sugieren una falta de información de las usuarias y proveedores con respecto a factores que están asociados con un riesgo mayor de problemas de salud durante el uso de anticonceptivos orales.
Resumé Pour évaluer dans quelle mesure les utilisatrices et non utilisatrices de contraceptifs oraux sont sensibilisées aux facteurs associés à des complications, cette étude a comparé la fréquence des facteurs et des maladies qui contribuent au risque que présente l'utilisation de ces contraceptifs. Dans l'Etat de Sao Paulo (Brésil), des données ont été recueillies auprès de 5317 utilisatrices et 8863 non utilisatrices, au moyen de questionnaires demandant des renseignements concernant les variables suivantes: utilisation de contraceptifs oraux, âge, poids, tabagisme, présence ou antécédents d'hypertension, diabète, cardiopathies, varices douloureuses et épilepsie. La moitié des utilisatrices présentaient certains facteurs de risque et 17,4% des facteurs de risque élevé de complications résultant de l'utilisation de contraceptifs oraux. Les facteurs de risque et les maladies dont la population semblait mal connaître l'effet d'augmentation des risques qu'entrîne l'ingestion de contraceptifs oraux étaient le tabagisme, l'hypertension et les varices douloureuses. Un faible pourcentage seulement de la population paraissait savoir que ces maladies et facteurs pouvaient accroître les risques de problèmes de santé durant l'utilisation des contraceptifs oraux. Les résultats suggèrent que les utilisatrices et les pourvoyeurs des services de contraception ne sont pas suffisamment informés des facteurs associés à un risque accru de problèmes de santé durant l'utilisation des contraceptifs oraux.相似文献
55.
S O'Núnáin N J Linker J F Sneddon N M Debbas A J Camm D E Ward 《British heart journal》1992,67(1):67-71
OBJECTIVE--To assess the effects of low energy ablation of the substrate for atrial flutter. DESIGN--Initial retrospective analysis of patients undergoing low energy ablation of the atrioventricular node for refractory atrial flutter (group 1) was followed by a prospective assessment of low energy ablation in the posterio-inferior right atrium for the same condition (group 2). SETTING--Tertiary referral centre for management of cardiac arrhythmias. PATIENTS--Seven men (aged 50-67 years) with refractory atrial flutter. INTERVENTIONS--Multiple (3-10) low energy DC shocks with a cumulative energy of 100-245 J in the region of the atrioventricular node in group 1 and 12-15 low energy DC shocks (cumulative energy 110-235 J) guided by the anatomical landmarks of the triangle of Koch and applied directly to the atrial wall. MAIN OUTCOME MEASURE--Freedom from recurrence of atrial flutter. RESULTS--In group 1 despite initial complete atrioventricular block in three patients, atrioventricular conduction had resumed in all by one month. All four, however, were in sinus rhythm at follow up six to 13 months later. Two of the three patients in group 2 were free of atrial flutter at follow up three to four months after ablation. CONCLUSION--Ablation of the atrial flutter substrate with low energy DC shocks is feasible. Precise electrophysiological mapping is not necessary. 相似文献
56.
Silber SJ; Nagy Z; Devroey P; Tournaye H; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(11):2422-2428
The aim of the study was to determine whether a prior diagnostic testicle
biopsy can predict success or failure of testicular sperm extraction (TESE)
with intracytoplasmic sperm injection (ICSI) in patients with
non-obstructive azoospermia caused by testicular failure, and what is the
minimum threshold of sperm production in the testis which must be surpassed
for spermatozoa to reach the ejaculate. Forty- five patients with
non-obstructive azoospermia caused by testicular failure underwent
diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure.
The diagnostic testicle biopsy was analysed quantitatively, and correlated
with the quantitative findings of spermatogenesis in patients with normal
spermatogenesis, as well as with the results of subsequent attempts at
TESE-ICSI. Men with non- obstructive azoospermia caused by germinal failure
had a mean of 0-6 mature spermatids/seminiferous tubule seen on a
diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in
men with normal spermatogenesis and obstructive azoospermia. These findings
were the same for all types of testicular failure whether Sertoli cell
only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia.
Twenty-two of 26 men with mature spermatids found in the prior testis
biopsy had successful retrieval of spermatozoa for ICSI, 12 of their
partners became pregnant, and are either ongoing or delivered. The study
suggests that 4-6 mature spermatids/tubule must be present in the testis
biopsy for any spermatozoa to reach the ejaculate. More than half of
azoospermic patients with germinal failure have minute foci of
spermatogenesis which are insufficient to produce spermatozoa in the
ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for
the presence of mature spermatids) can predict subsequent success or
failure with TESE-ICSI. Incomplete testicular failure may involve a sparse
multi-focal distribution of spermatogenesis throughout the entire testicle,
rather than a regional distribution. Therefore, it is possible that massive
testicular sampling from many different regions of the testes may not be
necessary for successful TESE-ICSI.
相似文献
57.
β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis. 相似文献
58.
59.
J K Sakurada A Maury W M Tamashiro P M Araújo I J Camargo H A Rangel 《Research in immunology》1992,143(2):157-164
To verify whether anti-Trypanosoma-cruzi-proteinase antibodies are able to play a role in the development of Chagas' disease, CBA/J and C57BL/6 mice were immunized with purified proteinase fractions: antibody production was studied and passive immunization experiments were carried out. No significant differences were observed in the titre, isotype composition and specificity of the antibodies produced by the mouse strains. Immune sera produced in one strain was able to protect mice of both strains, provided that the challenge did not exceed the number of parasites corresponding to 30-fold the LD50. The data presented suggest that anti-proteinase antibodies may play a role in immunoprotection. 相似文献
60.
Because of its numerous etiologies, foot dermatitis can be difficult to diagnose despite of thorough history and physical examination. The differential diagnoses are challenging and include allergic contact dermatitis, dyshidrosis, juvenile plantar dermatosis, atopic dermatitis, lichen planus.
Methods: In the Cutaneous Allergology Unit of the Department of Dermatovenereology of Pedro Hispano Hospital, between 1999 and 2003, 804 patients were observed with suspicion of contact dermatitis. In 9,3% there was a history of recurrent foot dermatitis. All these patients were patch tested with GPEDC standard and shoe series and shoe fragments.
Results: Twenty‐five patients revealed shoe contact dermatitis with positive reactions to the series tested, with an average age of 40 years. The dermatitis involved the dorsal aspect of the foot in 20 patients and the volar aspect in 8, the lateral aspects in 4, typically sparing the instep and flexural creases of the toes. The most common allergen were para‐tertiary‐butylphenol formaldehyde resin – PTBFR (12 patients‐48%), mercapto mix (7 patients‐28%), potassium dichromate (24%), mercaptobenzothiazole (24%).
Conclusions: The most common causes of shoe contact dermatitis were glues, followed by rubber components and chromated leather. As in other studies the most common allergen in shoe dermatitis in Portugal is PTBFR in neoprene adhesives. Rubber components (accelerators) were the second more frequent allergen in this study, probably a direct result of improved fixation of chrome and a change in footwear style and chrome sensitivity explains leather allergy. Other causes of foot contact dermatitis are iatrogenic complication, clothing (socks), cosmetics, adhesive tape and professional etiology. 相似文献
Methods: In the Cutaneous Allergology Unit of the Department of Dermatovenereology of Pedro Hispano Hospital, between 1999 and 2003, 804 patients were observed with suspicion of contact dermatitis. In 9,3% there was a history of recurrent foot dermatitis. All these patients were patch tested with GPEDC standard and shoe series and shoe fragments.
Results: Twenty‐five patients revealed shoe contact dermatitis with positive reactions to the series tested, with an average age of 40 years. The dermatitis involved the dorsal aspect of the foot in 20 patients and the volar aspect in 8, the lateral aspects in 4, typically sparing the instep and flexural creases of the toes. The most common allergen were para‐tertiary‐butylphenol formaldehyde resin – PTBFR (12 patients‐48%), mercapto mix (7 patients‐28%), potassium dichromate (24%), mercaptobenzothiazole (24%).
Conclusions: The most common causes of shoe contact dermatitis were glues, followed by rubber components and chromated leather. As in other studies the most common allergen in shoe dermatitis in Portugal is PTBFR in neoprene adhesives. Rubber components (accelerators) were the second more frequent allergen in this study, probably a direct result of improved fixation of chrome and a change in footwear style and chrome sensitivity explains leather allergy. Other causes of foot contact dermatitis are iatrogenic complication, clothing (socks), cosmetics, adhesive tape and professional etiology. 相似文献