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1.
Leptospiral antigens in the liver of experimentally infected guinea pig and their relation to the morphogenesis of liver damage. 总被引:3,自引:0,他引:3
V A Alves L C Gayotto T De Brito R T Santos A Wakamatsu M R Vianna E E Sakata 《Experimental and toxicologic pathology》1992,44(7):425-434
In order to investigate the morphogenes of experimental leptospirosis by morphologic and immunohistologic methods, 24 guinea-pigs were inoculated intraperitoneally with L. interrogans serogroup Icterohaemorrhagiae. They were divided in 6 groups, sacrificed from the 1st to the 6th day of infection. Semiquantitative analyses of histopathological liver lesions were performed in 1 micron sections of tissue embedded in glycol-methacrylate. The distribution of leptospiral antigen (L. Ag) and its glycolipoprotein (GLP) was demonstrated by peroxidase-antiperoxidase on paraffin embedded tissue. Significant lesions appeared at the 4th day of infection, progressing to a peak on the 6th day. Inflammation was associated with injury of the portal triad. Liver cells showed either swelling or acidophilic degeneration and necrosis, together with loss of cell cohesion, leading to disarray of liver cell plates. Mitochondria were found progressively enlarged and irregularly distributed. L. Ag expression was parallel to the morphological changes. Portal distribution was significant at the 4th day and on later stages centrilobular localization became predominant. Spiral forms suggestive of intact leptospires were initially found but, chiefly at the 6th day, L. Ag was seen in granules, probably resulting from phagocytosis. GLP staining was similar to granular L. Ag in morphology, and distribution. Cytokeratin condensation was seen in liver cells with acidophilic necrosis and was marked in areas of disorganization of cell plates. Our findings lead us to hypothesize a direct leptospiral cytotoxic effect on endothelial and on liver-cell membranes. At first, leptospires themselves would induce subcellular changes acting mainly on membrane permeability. Afterwards, their granular forms, including GLP, would act as adjuvant factors. These findings demonstrate that the disarray of liver cell plates at the late phase of the disease is genuine. 相似文献
2.
Anti-inflammatory effects of fructose-1,6-bisphosphate on carrageenan-induced pleurisy in rat. 总被引:3,自引:0,他引:3
José Carlos Farias Alves Filho Roberto Christ Vianna Santos Telmo Abelin Castaman Jarbas Rodrigues de Oliveira 《Pharmacological research》2004,49(3):245-248
In the present study, we evaluated the effect of fructose-1,6-bisphosphate (FBP), a high energy intermediate metabolite of glycolysis, in an acute model of lung injury. Injection of carrageenan into the pleural cavity of rats elicited an acute inflammation response characterized by a fluid accumulation in the pleural cavity which contained a large number of polymorphonuclear neutrophils. FBP (500mg/kg) attenuated the inflammation parameters: exudate volume, total leukocytes and the number of polymorphonuclear leukocytes, but the protein concentration in the exudate was not significantly affected by treatment with FBP. The precise site and mechanism of the anti-inflammatory effect was not addressed, considering the diverse pharmacological actions of FBP. This drug has anti-inflammatory actions suggesting that it may represent a novel strategy for the modulation of inflammatory response. 相似文献
3.
4.
Monteiro SC Stefanello FM Vianna LP Matte C Barp J Belló-Klein A Trindade VM Wyse AT 《Metabolic brain disease》2005,20(1):35-44
In the present work we investigated the effect of ovariectomy on acetylcholinesterase (AChE) activity and ganglioside content in cerebral cortex of female rats. We also studied the activity of butyrylcholinesterase (BuChE) in serum of these animals. Adult Wistar rats were divided into three groups: (1) naive females (control), (2) sham-operated females and (3) castrated females (ovariectomy). Thirty days after ovariectomy, rats were sacrificed by decapitation without anaesthesia. Blood was collected and the serum used for BuChE determination. Cerebral cortex was homogenized to determine AChE activity and extracted with chlorophorm:methanol for ganglioside evaluation. Results showed that rats subjected to ovariectomy presented a significant increase of AChE activity, but did not change the content and the profile of gangliosides in cerebral cortex when compared to sham or naive rats. BuChE activity was decreased in serum of rats ovariectomized. Our findings suggest that the alteration in the activity of brain AChE, as well as serum BuChE activity caused by ovariectomy may contribute to the impaired cognition and/or other neurological dysfunction found in post-menopausal women. 相似文献
5.
Karina Mary de Paiva Vianna Maria Regina Alves Cardoso Rui Manuel Calejo Rodrigues 《Noise & health》2015,17(76):125-133
Since 1972, the World Health Organization (WHO) has declared noise as a pollutant. Over the last decades, the quality of the urban environment has attracted the interest of researchers due to the growing urban sprawl, especially in developing countries. The objective of this study was to evaluate the effects of noise exposure in six urban soundscapes: Areas with high and low levels of noise in scenarios of leisure, work, and home. Cross-sectional study. The study was conducted in two steps: Evaluation of noise levels, with the development of noise maps, and health related inquiries. 180 individuals were interviewed, being 60 in each scenario, divided into 30 exposed to high level of noise and 30 to low level. Chi-Square test and Ordered Logistic Regression Model (P < 0,005). 70% of the interviewees reported noticing some source of noise in the selected scenarios and it was observed an association between exposure and perception of some source of noise (P < 0.001). 41.7% of the interviewees reported some degree of annoyance, being that this was associated with exposure (P < 0.001). There was also an association between exposure in different scenarios and reports of poor quality of sleep (P < 0.001). In the scenarios of work and home, the chance of reporting annoyance increased when compared with the scenario of leisure. We conclude that the use of this sort of assessment may clarify the relationship between urban noise exposure and health. 相似文献
6.
Bartolazzi Frederico Ribeiro Antônio Luiz Pinho de Sousa Waleska Jaclyn Freitas Nunes Vianna Mayara Sousa da Silva José Luiz Padilha Martins Maria Auxiliadora Parreiras 《Journal of thrombosis and thrombolysis》2021,52(4):1074-1080
Journal of Thrombosis and Thrombolysis - Oral anticoagulant therapy (OAT) has increased substantially due to the aging population and prevalence rise of atrial fibrillation (AF). Medication... 相似文献
7.
From 1941 to 1970 260 cases of Rocky Mountain spotted fever were documented in Suffolk County, Long Island. A marked decline in the over-all attack rate during the past three decades and in incidence during the last decade was observed. The decline in incidence corresponds well with the period of maximum suburbanization in Suffolk County, Long Island, and may be related to land cultivation and use of insecticides which eliminate favorable flora and animal hosts for the tick vector, Dermacentor variabilis. 相似文献
8.
Normal venous circulation of the gastroesophageal junction. A route to understanding varices 总被引:7,自引:0,他引:7
A Vianna P C Hayes G Moscoso M Driver B Portmann D Westaby R Williams 《Gastroenterology》1987,93(4):876-889
A study into the normal anatomy of the venous circulation of the gastroesophageal junction was undertaken using three complementary techniques (radiology, corrosion casting, and morphometry). Four distinct zones of venous drainage were defined as follows: (a) gastric zone, characterized by a longitudinal venous distribution; (b) palisade zone, composed of parallel vessels arranged in groups, lying mainly within the lamina propria; (c) perforating zone, characterized by "treble clef" shaped veins, which collect and channel blood into extrinsic veins; and (d) truncal zone, composed of four or five deep lying descending veins. This venous system appeared to be mainly distributed within the esophageal mucosal folds. The anatomic pattern suggests that venous flow is bidirectional at the palisade zone, which acts as a high-resistance watershed region between the portal and azygos systems. In patients with portal hypertension this normal vascular system has to accommodate greatly increased venous flow, and the anatomy as demonstrated here offers insight into variceal development. 相似文献
9.
Warley Oliveira Silva Renata Perez Vianna Silva Macedo Giselle Nevares Renata Costa Val Rodrigues Juliana Francisca Grossi Heleno Andréa Vaz Braga Pintor Bernardo Mattos Almeida 《Journal of endodontics》2021,47(1):3-10
IntroductionThe management of endodontic emergencies has been particularly challenging during the coronavirus disease 2019 (COVID-19) outbreak because of the possible generation of airborne particles and aerosols. The aim of this report was to contribute to the practice of endodontics by proposing a general protocol for the management of emergencies showing the rationale for remote diagnosis, clinical procedures, and the use of personal protective equipment and barriers at the dental office during the COVID-19 outbreak.MethodsA review of the literature was conducted up to May 2020 on relevant institutional sites, aiming to retrieve the best updated evidence. The reporting considered the Reporting Tool for Practice Guidelines in Health Care statement.ResultsRecommendations from Cochrane Oral Health, the American Dental Association, and the Centers for Disease Control and Prevention were included along with the American Association of Endodontists resources and scientific articles that addressed the issue.ConclusionsThe proposed protocol could contribute to the management of endodontic emergencies at the dental office during the COVID-19 outbreak. 相似文献
10.
Karoline Baptista Vianna Lívia Gonalves Rodrigues Nathalia Trevisol Oliveira Joo Breno Ribeiro-Alvares Bruno Manfredini Baroni 《International Journal of Sports Physical Therapy》2021,16(2):459
BackgroundTraining programs that include the Nordic hamstring exercise (NHE) have been shown to increase eccentric knee flexor strength and biceps femoris fascicle length in male athletes. However, the effect of NHE on female athletes remains unknown.PurposeTo investigate the collective and individual responses of professional female soccer players engaged in a preseason training program with the NHE regarding eccentric knee flexor strength and biceps femoris long head fascicle length.Study DesignQuasi-experimental study.MethodsSixteen amateur female soccer players (without a NHE training routine) were evaluated 8-weeks apart to: (1) assess reliability of eccentric knee flexor strength and biceps femoris fascicle length measures; and (2) determine the typical error of measures that would be used to discriminate training responders and non-responders. The NHE training group had 17 professional female soccer players who performed an 8-week training program with the NHE during preseason. Within-group analysis was performed with paired sample t-tests (pre- vs. post-training), and individual responses were determined using the typical error criteria.ResultsThe non-trained group’s data demonstrated that measures of strength (ICC=0.82-0.87, typical error = 12-13 N) and fascicle length (ICC=0.92-0.97; typical error = 0.19-0.38 cm) were reliable. In the NHE training group, both limbs increased the eccentric knee flexor strength (~13%; ES=0.74-0.82) and the biceps femoris fascicle length (~6%; ES=0.44-0.65). Twelve players (~71%) were considered responders to the NHE training program for the eccentric knee flexor strength, while eight athletes (~47%) were responders for the biceps femoris fascicle length.ConclusionThe 8-week preseason training program with the NHE increased both eccentric knee flexor strength and biceps femoris fascicle length in professional female soccer players. More than two-thirds of players demonstrated a meaningful increase in eccentric strength, while nearly half achieved consistent fascicle length increases with the NHE training. 相似文献