Medicina

Projetos de Pesquisa

Já dizem os sábios que a pergunta promove o conhecimento. Pensando nisso, a Facisa, FCM e Esac encontram no investimento à pesquisa a oportunidade de promover a descoberta de soluções que façam a academia contribuir com a melhoria da sociedade. Tal decisão tem feito os nomes das instituições alcançarem o hall dos primeiros lugares em eventos nacionais e a chance de estarem entre os escolhidos para eventos internacionais. Assumindo o compromisso de formar profissionais conscientes da necessidade da pesquisa, a Facisa, FCM e Esac cresce e cumpre a missão de, através de suas descobertas, melhorar a vida em sociedade.

Learning and survival memory undergoing a permanent bilateral carotid ligation in rats

Abstract

Purpose: To evaluate the effect of cerebral hypoxia-ischemia on memory and learning survival of rats submitted to permanent bilateral carotid ligation (PBCL).

Methods: Twenty-four survivors of PBCL were evaluated after 30 days with regard to memory and learning using a water survival maze. Twenty-three healthy rats were used as control group. The results were expressed by their means and standard error of the mean (SEM). p < 0.05 was used for rejecting the null hypothesis. The study was approved by the Ethics Committee for animal investigation.

Results: The mortality rate for the surgery was 44.4%. The latency time to find the survival platform was higher in rats that underwent PBCL (Normal: 10.24 ± 1.85s – Study: 25.30 ± 4.69s - Mann–Whitney p=0.0388). Additionally, the type of swimming and the spatial stability of the studied rats on the survival platform were compromised in these animals.

Conclusion: The permanent bilateral carotid ligation induces change in the learning and survival memory.

Translational realistic expectations of chronic cerebral hypoxemia in rat model after bilateral commom carotid artery ligation. Neurocognitive aspects

Abstract

Purpose: To evaluate the effects of chronic cerebral hypoxia on memory of rats submitted to bilateral common carotid artery ligation (BCCL).

Methods: Every each week, for 16 weeks, 31 rats were tested for memory using a water and land mazes and compared with 30 normal rats (control group A). The variables were expressed by their mean and standard error of the mean (SEM). p < 0.05 was used for rejecting the null hypothesis. The study was approved by the Ethics Committee for animal investigation.

Results: There was a significant increase in the latency time, in the survival water and land mazes, after four weeks (study group B) follow-up. However, without any medication or therapeutically induced measures, after 16 weeks (study group C) follow-up the latency mean times tend to be similar to control group (A) in the neurocognitive tests.

Conclusions: Neurocognitive deficits after 16 weeks post-operative follow-up of rats that underwent bilateral common carotid artery ligation is a natural adaptive phenomenon. Thus, is not realistic to allow translational information from this animal model for therapeutically approaches aiming at to prevent, or to improve brain damage in human beings suffering from chronic deprivation of adequate blood supply.

Severe autogenously fecal peritonitis in Wistar rats with permanent bilateral carotid occlusion. Response to intra peritoneal moxifloxacin combined with dexamethasone

Abstract

Purpose: To evaluate the treatment outcome of severe peritonitis in rats submitted to permanent bilateral carotid occlusion (PBCO).

Methods: Sixteen Wistar rats (mean age of 8.5 months) with PBCO underwent autogenously fecal peritonitis, and were treated with moxifloxacin combined with dexamethasone, and followed-up for 45 days. Ten rats (mean age five months) without PBCO were used as a control group. The variables were expressed by their mean and standard error of the mean (SEM). p < 0.05 was used for rejecting the null hypothesis. The study was approved by the Ethics Committee.

Results: There was a significant increase (p=0.0002) in the mortality and morbidity in older rats that underwent PBCO (study group). However, even among the survival rats presenting with severe residual abscesses both in the abdomen and thorax cavities, they present an almost normal life.

Conclusions: The treatment of severe autogenously fecal peritonitis with intraperitoneal moxifloxacin combined with dexamethasone was very effective in young rats without permanent bilateral carotid occlusion. The treatment reached reasonable results in older rats with PBCO, even considering residual abscesses on abdomen and thorax. Older age was the greater risk factor for the outcome of the treatment of severe peritonitis. Sepsis remains a challenging situation, especially in elderly.

Autogenous fecal peritonitis in Wistar rats with permanent bilateral carotid occlusion. Morbidity, mortality and microbiological response

Abstract

Purpose: To investigate morbidity, mortality and microbiological response to fecal peritonitis induced in Wistar rats with permanent bilateral carotid ligation (PBCL).

Methods: Fecal peritonitis was induced in 30 rats, with 10 animals in each group: Group1 - normal young animals; Group2 - normal mature animals; and Group3 – rats with PBCL after four months postoperative follow-up. Peritonitis was induced with 10% stool suspension. Morbidity and mortality were evaluated. The survival animals after seven days were euthanized for tests. For microbiological studies blood were collected from the carotids and right ventricle; and fragments of lung and peritoneum.

Results: The morbidity and mortality of young animals were significantly lower than in mature animals with and without PBCL. There was no difference in morbidity and mortality among mature rats with and without PBCL. The diversity of microorganisms producing septicemia was similar to native micro biota of the large bowel.

Conclusions: The immune response was more efficient in young animals, represented by significant less morbidity and no natural mortality. PBLC did not affect morbidity and mortality in mature rats. The immune response to fecal peritonitis has age as an independent predictor.

Congenital cataract can be prevented by using moxifloxacin and dexamethasone intraperitoneally in pregnant Wistar rats that underwent autologous fecal peritonitis

Abstract

Purpose: To investigate the impact of moxifloxacin combined with dexamethasone intraperitoneally in Wistar rats subjected to autogenous fecal peritonitis, assessing brains and eyes of the offspring.

Methods: Four pregnant rats, weighing between 280 and 320 grams underwent autogenous induction of fecal peritonitis, with a 10% suspension at a dose of 4 ml per kilogram of rat, on the ninth day of pregnancy. Four uninfected pregnant rats served as control group. The four infected rats received a single dose of moxifloxacin and dexamethasone intraperitoneally at doses of 40 mg and 0.2 mg per kg of rat, 48 hours after induction of peritonitis (study group). The brains were analyzed and weighed on the first day after birth, before any food. Also the eyes were examined and photographed. Differences between means were evaluated by the "t" test for independent samples. P < 0.05 was used for rejecting the null hypothesis. The project was approved by the Ethics Committee for Animal.

Results: The mean weight of the brains of offspring from the rats that received 4 ml per kilogram of 10% feces suspension and received antimicrobial therapy were similar to those offspring from rats in the control group (χcontrol group 0.201 ± 0.016 g versus χstudy group 0.201 ± 0.013 = g - p> 0.05). Additionally, the brains from the study group presented normal morphology and congenital cataract was not observed in any of offspring.

Conclusions: The findings support the hypothesis that the use of moxifloxacin associated with dexamethasone in the peritoneal cavity of pregnant rats that developed autogenously feces peritonitis is effective in maintaining the consistency and the weights of the newborn brains and prevents the production of congenital cataract. The translation to human beings is that the effects of intra-abdominal infection in pregnant women may be minimized with the use of moxifloxacin associated with dexamethasone intraperitoneally.

Congenital Cataract Due To Autogenously Fecal Peritonites In Pregnant Wistar Rats

Opacification of the normally transparent crystalline lens (cataract) can be congenital, usually caused by changes that occur during embryonic development. In human beings bilateral congenital cataract is the most common cause of treatable childhood blindness. Among the causes of human congenital cataract are intrauterine infections (toxoplasmosis, rubella, cytomegalovirus, herpes, varicella and syphilis). As regard to experimental model of this disease, it is well recognized that congenital cataract is present in over 45% of the offspring of diabetic rats. Hypercholesterolemic mother rats can also have pups with congenital cataract. Additionally, excessive maternal caffeine exposure during pregnancy can be cataractogenic for neonatal crystalline lenses in these animals

To the best of our knowledge there is no experimental rat model associating bacterial peritonitis and congenital cataract. Thus, the purpose of this study is to report the occurrence of this congenital anomaly in newborn rats from mothers that underwent autogenously fecal peritonitis early in pregnancy; and also to show two antimicrobial treatments for sepsis and their effect in the prevention of this condition.

Moxifloxacin e dexametasona intraperitoneal em ratas Wistar prenhas submetidas à peritonite fecal autógena: análise dos pesos dos recém-nascidos e de seus encefalos

Resumo

Objetivo: Investigar o impacto do moxifloxacin associado a dexametasona intraperitoneal nas ratas Wistar submetidas a peritonite fecal autógena, avaliando os pesos corpóreos e dos encéfalos nos recém-nascidos.

Métodos: Quatro ratas prenhas, pesando entre 280 e 320 gramas foram submetidas a indução de peritonite fecal autógena, com suspensão a 10%, na dose de 4 ml por quilo de rata, no nono dia de prenhez. Um lote de quatro ratas prenhas não infectadas serviu como grupo controle. Adicionalmente, duas ratas, igualmente infectadas, receberam dose única de moxifloxacin e dexametasona, por via intraperitoneal, nas doses de 40 mg e 0,2mg por kg de rata, respectivamente, 48h e 72h após a indução da peritonite. Os recém-nascidos e seus encéfalos foram pesados no primeiro dia após o nascimento, antes de qualquer alimentaçao. As diferenças entre as médias dos pesos foram avaliadas pelo teste de Kruskal-Wallis, seguido do pós-teste de Dunn. A significância estatística foi estabelecida ao nível de p < 0,05. O projeto foi aprovado pelo Comitê de Ética para Investigação em Animais da Faculdade de Ciências Médicas da Campina Grande – Paraiba.

Resultados: As médias dos pesos dos recém-nascidos e de seus encêfalos das ratas que receberam 4 ml por quilo da suspensão de fezes foram significantemente menores do que os similares nascidos das ratas do grupo controle (χ4ml = 5,563 ± 0,514 g versus χcontrole = 5,618 ± 0,326 g – p = 0,0416 – pesos corpóreose χ4ml = 0,170 ± 0,029 g versus χcontrole = 0,201 ± 0,016 g – p = 0,001 – pesos encefálicos. As médias dos pesos corpóreos (χcontrole = 5,618 ± 0,326 g versus χinterveção48h = 5,907 ± 0,320 g e versus χintervenção72h = 5,973 ± 0,185 g – p ≤ 0,5) e dos encéfalos de recém-nascidos das ratas prenhas que receberam moxifloxacin e dexametasona 24h e 48h após a indução da peritonite foram similares (χcontrole = 0,201 ± 0,016 g versusχinterveção48h = 0,201 ± 0,013 g e versus χintervenção72h = 0,221 ± 0,017 g – p ≤ 0,5 – pesos encefálicos).

Conclusões: Os achados dão suporte à hipótese de que o uso de moxifloxacin associado a dexametasona na cavidade peritoneal de ratas prenhas que desenvolveram peritonite fecal autógena é eficaz na manutenção dos pesos corpóreo e encefálico dos recém-nascidos. A translação para seres humanos é a de que os efeitos da infecção intra-abdominal em gestantes podem serminimizados com o uso de moxifloxacin associado a dexametasona por via intraperitoneal.