Determinação das doses letal 50 e 100 do propofol em nanoemulsão ou em emulsão lipídica pela via intraperitoneal em camundongos

The formulation of a drug can interfere with its absorption into the circulatory system and may result in changes in the dose required to achieve that particular effect. The aim of this study was to determine the lethal dose 50 (LD 50) and 100 (LD100) of a nanoemulsion of propofol and the lipid emulsion in mice intraperitoneally. One hundred sixty animals weighing 36.47 +/- 4.6g, which were distributed randomly into two groups: NANO and EMU who received propofol 1% in the nanoemulsion and lipid emulsion, respectively, intraperitoneally. Began with a dose of 250mg/kg (n=10) and from this isdecreased or increased the dose until achieving 0 and 100% of deaths in each group thus formed were seven subgroups in NANO (each subgroup n = 10) at doses 200, 250, 325, 350, 400, 425 and 475 mg/kg and in EMU eight subgroups (n= 10 each subset) 250, 325, 350, 400, 425, 475, 525 and 575 mg/kg. In the CONTROL group (n= 10) animals received saline in the largest volume used in the other groups to rule out death by the volume injected. Analysis of LD 50 and LD 100 were obtained by linear regression. The LD 50 was 320, 95 mg / kg and 4243, 51mg / kg and the LD 100 was445.99 mg / kg and 595.31 mg / kg to groups NANO and EMU, respectively. It follows that nanoemulsion is propofol in 25% more potent compared to the lipid emulsionintraperitoneally.

Heart Failure After Myocardial Infarction: Clinical Implications and Treatment

Heart failure is a frequent complication of myocardial infarction. Several factors, such as recurrent myocardial ischemia, infarct size, ventricular remodeling, stunned myocardium, mechanical complications, and hibernating myocardium influence the appearance of left ventricular systolic dysfunction after myocardial infarction. Importantly, its presence increases the risk of death by at least 3- to 4-fold. The knowledge of the mechanisms and clinical features are essential for the diagnosis and treatment of left ventricular dysfunction and heart failure after myocardial infarction. Therefore, this review will focus on the clinical implications and treatment of heart failure after myocardial infarction.

Immunosuppressant Prograf (R) (Tacrolimus) Induces Histopathological Disorders in the Peritubular Tissue of Rat Testes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Structural alterations in the seminiferous tubules of rats treated with immunosuppressor tacrolimus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Apoptosis during the seasonal spermatogenic cycle of Rana catesbeiana

In the bullfrog Rana catesbeiana, testicular weight is constant throughout the year, but the volume densities of germinative and interstitial compartments undergo inverse changes from winter (non-breeding) to summer (breeding). The occurrence of apoptosis in the seminiferous lobules of bullfrogs was investigated in these two periods using sections stained with haematoxylin and eosin (H&E), the TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling) method and transmission electron microscopy. TUNEL-positive cells were observed in the seminiferous lobules, and ultrastructural morphological details confirmed the occurrence of cell death by apoptosis. In summer, the occurrence of several spermatogenic processes (in addition to spermiogenesis and spermiation), and then the overconsumption of Sertoli cell-derived pro-survival factors, could be responsible for the increased density of apoptotic cells. Alternatively, the low apoptotic frequency in winter could be related to the constant homeostasis in the germinative compartment given that most lobules are filled with primary spermatocytes. As volume densities of interstitial and germinative compartments undergo inverse seasonal variations through the year, the incidence of apoptosis (in summer) could play a part in controlling the spermatogenic process, maintaining the lobular size when interstitial tissue is maximally developed. In winter, the low apoptotic cell density leads to spermatogenic recrudescence and, thereby, the production of an adequate quantity of spermatozoa for the next breeding period. Thus, apoptosis may participate not only in the maintenance of spermatogenic homeostasis, but also in the cyclical control of the different spermatogenic processes according to seasonal changes of the testicular compartments as a whole.

Area of Rests of Malassez in Young and Adult Rat Molars: Evidences in the Formation of Large Rests

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Immunohistochemical detection of estrogen receptor beta in alveolar bone cells of estradiol-treated female rats: possible direct action of estrogen on osteoclast life span

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Morphological evidences indicate that the interference of cimetidine on the peritubular components is responsible for detachment and apoptosis of Sertoli cells

Cimetidine, referred as antiandrogenic agent, has caused alterations in the seminiferous tubules, including alterations in the peritubular tissue and death of myoid cells by apoptosis. Regarding the structural and functional importance of the peritubular tissue for the maintenance of Sertoli cells (SC), we purpose to investigate the SC-basement membrane interface, focusing the morphological features of SC and their interaction with the basement membrane in the affected tubules by cimetidine. Ten animals were distributed into two groups, control (CG) and cimetidine (CmG) which received saline solution and 50 mg of cimetidine per kg of body weight, respectively, for 52 days. The testes were fixed, dehydrated and embedded for analyses under light and transmission electron microscopy. Paraffin sections were submitted to the TUNEL method; sections of testes embedded in glycol methacrylate were submitted to PAS method and stained by H&E for morphological and quantitative analyses of Sertoli Cells. In the CmG, the SC nuclei were positive to the TUNEL method and showed typical morphological alterations of cell death by apoptosis (from early to advanced stages). A significant reduction in the number of Sertoli Cells was probably due to death of these cells by apoptosis. A close relationship between SC nuclear alterations (including a high frequency of dislocated nuclei from the basal portion) and damage in the peritubular tissue was observed. The ultrastructural analysis showed a parallelism between the gradual advancement of apoptotic process in SC and detachment of the anchoring sites (hemidesmosomes) of SC plasma membrane from the lamina densa. The presence of portions of lamina densa underlying the detached hemidesmosomes indicates a continuous deposition of lamina densa, resulting in the thickening of the basal lamina. The results indicate a possible disarrangement of the SC cytoskeleton, including the focal adhesion structure. These alterations are related to SC apoptosis and probably result from disturbs induced by cimetidine on the peritubular tissue.

Cytotoxicity of fipronil on mice liver cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Interação silício-imidacloprid no comportamento biológico e alimentar de Schizaphis Graminum (Rond.) (Hemiptera: Aphididae) em plantas de trigo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Immunohistochemical evaluation of Ki-67 and PCNA in canine mammary neoplasias: Correlation with prognostic factors and clinical outcome

E-cadherin is a cell-cell adhesion molecule and low e-cadherin expression is related to invasiveness and may indicate a bad prognosis in mammary neoplasms. The expression of cell proliferation markers PCNA and especially Ki-67, has also proved to have a strong prognostic value in this tumor class. The expression of these markers was related to the clinical-pathological characteristics of 73 surgically removed mammary tumors in female dogs by immunohistochemistry. There was no statistical correlation between these markers and death by neoplasm, survival time and disease-free interval. However, the loss of e-cadherin expression and marked Ki-67 expression (p=0.016) were considered statistically significant for the diagnosis (p=0.032). When evaluated as independent factors, there was evidence of the relationship between the loss of e-cadherin expression and high PCNA expression with changes in the body status (divided into obese, normal and cachectic) of female dogs (p=0.030); there was also evidence of the relationship between pseudopregnancy and e-cadherin alone (p=0.021) and for ulceration and PCNA alone (p=0.035). The significant correlation between the markers expression and these well known prognostic factors used individually or in combination suggests their prognostic value in canine mammary tumors.

Enhanced ERbeta immunoexpression and apoptosis in the germ cells of cimetidine-treated rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cytotoxicity of monocrotaline in isolated rat hepatocytes: Effects of dithiothreitol and fructose

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae): Acid phosphatase and ATPase activities localization in salivary glands of females during the feeding period

This study investigates the presence and the localization of acid phosphatase and ATPase in the salivary glands of Rhipicephalus (Boophilus) microplus female ticks during feeding. Semi-engorged females showed a larger amount of acid phosphatase compared to those at beginning of feeding, localized mainly in the apical portion of the secretory cells, and in the basal labyrinth of the interstitial cells. Ultrastructural observations also demonstrated its presence in secretion granules and inside some nuclei of secretory cells at beginning of feeding. Acid phosphatase in a free form probably has a hemolymph and/or ribosomal origin and participates in salivary gland secretion control. ATPase was detected in basal membrane of all types of acini and/or in the cytoplasm of the secretory cells at both feeding stages. The enzyme activities found strongly suggests that cell death by apoptosis occurs during the degenerative process. © 2006 Elsevier Inc. All rights reserved.

Immunohistochemical evaluation of e-cadherin, Ki-67 and PCNA in canine mammary neoplasias: Correlation of prognostic factors and clinical outcome

E-cadherin is a cell-cell adhesion molecule and low e-cadherin expression is related to invasiveness and may indicate a bad prognosis in mammary neoplasms. The expression of cell proliferation markers PCNA and especially Ki-67, has also proved to have a strong prognostic value in this tumor class. The expression of these markers was related to the clinical-pathological characteristics of 73 surgically removed mammary tumors in female dogs by immunohistochemistry. There was no statistical correlation between these markers and death by neoplasm, survival time and disease-free interval. However, the loss of e-cadherin expression and marked Ki-67 expression (p=0.016) were considered statistically significant for the diagnosis (p=0.032). When evaluated as independent factors, there was evidence of the relationship between the loss of e-cadherin expression and high PCNA expression with changes in the body status (divided into obese, normal and cachectic) of female dogs (p=0.030); there was also evidence of the relationship between pseudopregnancy and e-cadherin alone (p=0.021) and for ulceration and PCNA alone (p=0.035). The significant correlation between the markers expression and these well known prognostic factors used individually or in combination suggests their prognostic value in canine mammary tumors.