Morphometric evaluation of gingival overgrowth and regression caused by cyclosporin in rats

Cyclosporin A is a selective immunosuppressant, used in organ transplants to prevent graft rejection. Cyclosporin A can cause various side effects including gingival overgrowth. The aim of this work was to evaluate gingival overgrowth of rats treated daily with 10 mg/kg body weight of Cyclosporin A for 60 days, as well as the regression after the interruption of treatment. All rats treated with Cyclosporin A developed gingival overgrowth, with increased thickness of the epithelium, height and width of the connective tissue. The density of fibroblasts and collagen fibers also increased. Five to 90 days after the interruption of treatment with Cyclosporin A, there was a progressive reduction of the gingival volume and of collagen fibers and fibroblast densities. The reduction was more pronounced in the initial periods and after 90 days did not return to the normal values.

Características morfológicas do osso alveolar de ratos tratados com ciclosporina-A ou tracolimus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Heteropterys tomentosa (A. Juss.) infusion counteracts Cyclosporin a side effects on the ventral prostate

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

Efeitos do FK-506 na regeneração de nervos após neurorrafia láteo-terminal: estudo em ratos

Pós-graduação em Bases Gerais da Cirurgia - FMB

Aloimunização de doadores de sangue como fonte de anti-soros e hemácias raras

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

Heat or cold chronic stress affects organ weights and Hsp70 levels in chicken embryos

This study was carried out with the objective of evaluating the effect of heat (38.8 degreesC) or cold (35.8 degreesC) stress on chicken embryo development and tissues Hsp70 levels, after the 13th day of incubation. Embryo weight (percent egg weight), organ weight (percent embryo weight) and Hsp70 levels (ng Hsp70 mug(-1) total protein) in different tissues (liver, breast muscle, heart, lungs, brain and kidney) were studied at the end of incubation. Cold stress induced a lower embryo weight and lower kidney and lungs weights, whereas heart and liver were lighter in heat-stressed embryos. An interaction between temperature and age was obtained only for Hsp70 levels in kidney and heart. Cold-stressed embryos showed higher Hsp70 levels in the brain, lungs and liver; a decrease in brain and breast muscle Hsp70 levels was seen from the 19th to 20th days in control embryos. Hsp70 levels increased with age in kidneys of control embryos and in heart of heat- and cold-stressed embryos. In conclusion, this study showed that chicken embryo organ weights are affected by incubation temperature, and that Hsp70 expression is tissue dependent (higher levels being seen in the brain) being cold-stress more effective in increasing Hsp70 levels in most studied tissues.

Percepção do corpo, medo da morte, religião e doação de órgãos

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

Organ tropism during the acute and chronic phases of Trypanosoma cruzi infection in BALB/c mice

The aim of the present study was to investigate the presence of Trypanosoma cruzi in the heart, liver, lung, and kidneys, using hemoculture and PCR analysis, of mice infected with different parasite strains during the acute and chronic phases of infection. Parasitemia curves revealed strain-specific biological behaviors. For the Y and JLP strains, the acute phase of infection started at days six and ten post-infection, parasitemia peaked at days seven and 15 post-infection, the chronic phase started at days nine and 28 post-infection, and animals started dying at days 19 and 120 post-infection, respectively. When the two strains were compared, the JLP strain exhibited reduced and slower replication rates associated with a delayed peak of parasitism and reduced parasite burdens. However, parasites were detected in all studied organs using PCR analysis. The capacity of both strains to infect different organs likely influences disease pathogenesis.

Caring for organ donors: the intensive care unit physicians' view

This study examined the meanings that the intensive care unit (ICU) physicians attribute to their practice when caring for brain-dead organ donors. It is a phenomenological study, a qualitative method that searches for describing and understanding the experiences lived. Data were collected through recorded individual interviews made with 10 ICU physicians who work in a university hospital in the interior of São Paulo, Brazil. Three categories emerged from data: (1) providing care for brain-dead organ donors; (2) relating to donors and their families; and (3) the ethical concerns and self-awareness of the physicians. There is consensus as to-many aspects: demand of technical qualification and excellence in practice; need of investing in technology of organ transplant; and donors seen as human beings and holders of human rights. Participants understand that family participation is decisive in the donation process, although interactions between the family members and the physicians are difficult because of the sensitive nature of the situation. The physicians often felt ill-prepared to openly discuss the topic of brain death and organ donation. Educational programs for physicians and family members may assist with this difficult process.

Natural killer activity in a medium-term multi-organ bioassay for carcinogenesis

Natural killer (NK) cell activity was evaluated after the initiation and promotion steps in a medium-term multi-organ bioassay for carcinogenesis. NK cell activity was assessed in vitro by Cr-51 release assay at the 4th and 30th weeks of the experiment. Male Wistar rats were sequentially initiated with N-diethylnitrosamine (DEN i.p.), N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN drinking water), N-methyl-N-nitrosourea (MNU i.p.), dihydroxy-di-N-propylnitrosamine (DHPN drinking water) and N,N'-dimethylhydrazine (DMH s.c.) at subcarcinogenic doses for 4 weeks (DMBDD initiation). One group was evaluated at the 4th week and the other was maintained without any further treatment until the 30th week. Two initiated groups were exposed through the diet to 2-acetylaminofluorene (2-AAF) or phenobarbital (PB), from the 6th until the 30th week, Five additional groups were studied to evaluate the effects of each initiator on NK activity. All groups submitted to initiation only, initiation plus promotion, or promotion only, developed significantly more preneoplastic lesions than the untreated control group. The main target organs for tumor development in the initiated animals n ere the liver and the colon, irrespective of treatment with 2-AAF or PB. NK cell activity was not affected bal exposure to genotoxic carcinogens after initiation, at the 4th week. Treatments only with PB or 2-AAF did not change NK cell activity, However, decreased NK cell activity was registered in the group only initiated with DMBDD and in the group given DMBDD+2-AAF. This late depression of NK cell activity at the 30th week could be related to the production of suppressing molecules by the tumor cells.

Lymphoproliferative response and T lymphocyte subsets in a medium-term multi-organ bioassay for carcinogenesis in Wistar rats

The lymphoproliferative response and T lymphocyte subsets were evaluated at different stages of carcinogenesis in male Wistar, rats sequentially initiated with N-diethylnitrosamine (DEN), N-butyl-N-4(hydroxybutyl)nitrosamine (BBN), N-methyl-N-nitrosourea (MNU), dihydroxy-di-N-propylnitrosamine (DHPN) and N,N'-dimethylhydrazine (DMH) (DMBDD initiation). One group was evaluated at the 4th week and other initiated group at the 30th week. Two initiated groups were also exposed through diet to 7-acetylaminofluorene (2-AAF) or phenobarbital (PB), from the 6th until the 30th week. Two groups received only 2-AAF or PB until the 30th week. Five groups were studied to evaluate the effects of each initiator. The lymphoproliferative response was induced in vitro by concanavalin A and the percentage of T lymphocyte subsets was determined by flow cytometry, All groups submitted to initiation only, initiation plus promotion, or promotion only, developed significantly more preneoplastic: lesions than the untreated control group. The main target organs for tumor development were the liver, colon, urinary bladder, kidneys and Zymbal glands, mainly in the group treated with DMBDD + 2-AAF, There were no alterations of the lymphoproliferative response and of the T lymphocyte subsets percentage in the DMBDD-treated group at the 4th and 30th weeks. At the 30th week, the T lymphocyte subsets percentage was also not affected in the initiated groups after treatments with 2-AAF or PB. The lymphoproliferative response, however, was decreased in the DMBDD + 2-AAF group and in the groups treated only with 2-AAF or PB, the present results indicate that the initiating chemicals used in the DMBDD initiation protocol do not exert any influence on the immune system. The alteration of lymphoproliferative response induced at the advanced stage of carcinogenesis without alteration of T lymphocyte subsets may indicate that the influence of 2-AAF and PB on the immune system is functional and not toxic. (C) 2000 Elsevier B.V. Ireland Ltd. All rights reserved.

Diuron exposure induces systemic and organ-specific toxicity following acute and sub-chronic exposure in male Wistar rats

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

Protective effects of carvedilol on systemic vascular damage induced by angiotensin II: Organ-specific effects independent of antihypertensive effects

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

Imidazoline receptors of the paraventricular nucleus on the pressor response induced by stimulation of the subfornical organ

In the present experiments we investigated a possible involvement of imidazoline receptors of the paraventricular nucleus (PVN) of the hypothalamus on the presser effects of the angiotensin LI (ANG II) injected into the subfornical organ (SFO), in male Holtzman rats (250-300 g) with a cannula implanted into the third ventricle (3rdV), PVN and SFO. At first we tested the participation of alpha(2) and imidazoline agonist and antagonist compounds on the presser effect of ANG II injected into the 3rdV. Based on the results we may conclude that clonidine associated with rilmenidine was able to block the hypertensive response to ANG IT. The ANG II (20 pmol) injected into SFO induced a robust increase in blood pressure (37 +/- 2 mmHg). Isotonic saline (0.15 M) NaCl did not produce any change in blood pressure (5 +/- 2 mmHg). The injection of rilmenidine (30 mu g/kg/l mu L), an imidazoline agonist agent injected into PVN before ANG II injection into SFO, blocked the presser effect of ANG II (5 +/- 2 mmHg). Also, the injection of idazoxan (60 mu g/kg/mu L) before rilmenidine blocked the inhibitory effect of rilmenidine on blood pressure (39 +/- 4 mmHg). The injection of clonidine (20 nmol/mu L) prior to ANG II into the 3rdV produced a decreased in arterial blood pressure (37 +/- 2 mmHg) to (15 +/- 4 mmHg). The injection of yohimbine (80 nmol/mu L) prior to clonidine blocked the effect of clonidine on the effect of ANG II (27 +/- 2 mmHg). The injection of rilmenidine prior to ANG TI also induced a decrease in arterial blood pressure (10 +/- 3 mmHg). The injection of idazoxan prior to rilmenidine also blocked the inhibitory effect of rilmenidine (24 +/- 3 mmHg). In summary, the present study demonstrated that rilmenidine decreases the hypertensive effect of ANG II, with more potency than clonidine, even when injected into 3rdV or PVN. This study established that the PVN interacts with SFO by imidazoline receptors in order to control the arterial blood pressure. (C) Elsevier, Paris.