C-kit(+) cells isolated from developing kidneys are a novel population of stem cells with regenerative potential.

The presence of tissue specific precursor cells is an emerging concept in organ formation and tissue homeostasis. Several progenitors are described in the kidneys. However, their identity as a true stem cell remains elusive. Here, we identify a neonatal kidney-derived c-kit(+) cell population that fulfills all of the criteria as a stem cell. These cells were found in the thick ascending limb of Henle's loop and exhibited clonogenicity, self-renewal, and multipotentiality with differentiation capacity into mesoderm and ectoderm progeny. Additionally, c-kit(+) cells formed spheres in nonadherent conditions when plated at clonal density and expressed markers of stem cells, progenitors, and differentiated cells. Ex vivo expanded c-kit(+) cells integrated into several compartments of the kidney, including tubules, vessels, and glomeruli, and contributed to functional and morphological improvement of the kidney following acute ischemia-reperfusion injury in rats. Together, these findings document a novel neonatal rat kidney c-kit(+) stem cell population that can be isolated, expanded, cloned, differentiated, and used for kidney repair following acute kidney injury. These cells have important biological and therapeutic implications.

Cisplatin plus paclitaxel and maintenance of bevacizumab on tumour progression, dissemination, and survival of ovarian carcinoma xenograft models.

BACKGROUND: Bevacizumab is being incorporated as first-line therapy with standard-of-care chemotherapy on epithelial ovarian carcinoma (EOC). We investigated bevacizumab combined with chemotherapy on tumour progression and mouse survival in EOC xenograft models. METHODS: Bevacizumab was administered concomitantly with cisplatin plus paclitaxel (DDP+PTX), continued after induction (maintenance) or started after chemotherapy. The effect on tumour progression was monitored by bioluminescence imaging (BLI) (1A9-luc xenograft). Tumour dissemination into the peritoneal organs and ascites formation (HOC22 xenograft) was evaluated by histological analysis at the end of treatment (interim) and at euthanasia (survival). The effects on overall survival (OS) were investigated in both EOC models. RESULTS: Bevacizumab with PTX+DDP delayed tumour progression in mice bearing EOC xenografts. OS was significantly extended, with complete responses, by bevacizumab continued after stopping chemotherapy in the HOC22 xenograft. Bevacizumab alone inhibited ascites formation, with only limited effect on tumour burden, but combined with PTX+DDP reduced ascites and metastases. Bevacizumab started after induction with PTX+DDP and maintained was equally effective on tumour progression and survival on 1A9-luc xenograft. CONCLUSION: Bevacizumab combined with chemotherapy not only affected tumour progression, but when administered as maintenance regimen significantly prolonged survival, reducing ascites, and tumour dissemination. We believe our findings are consistent with the clinical results and shed light on the potential effects of this kind of treatment on tumour progression.

Usefulness of transesophageal echocardiography during open heart surgery of mitral stenosis.

BACKGROUND: The aim of this study was to verify if the use of intraoperative transesophageal echocardiography (TEE), by detecting mitral insufficiency or residual stenosis during surgery, may improve medium term results in patients with severe mitral stenosis who undergo open heart valvuloplasty. METHODS: This prospective study included twenty-two patients (20 women and 2 men) with a mean age of 49+/-13 years with severe mitral stenosis. Mean follow-up was 32 months (range 12-55 months). All the patients underwent transthoracic echocardiography (TrE) before surgery and intraoperative TEE. Before surgery the mean transmitral gradient was 11+/-6.8 mmHg, the mean pressure half time (PHT) area was 0.89+/-0.19 cm2, the mean echo score was 8.9+/-2.2. Intraoperative TEE before the repair showed a mean echo score of 7.9+/-1.8. RESULTS: Two patients with unsatisfactory repair at TEE underwent immediate valve replacement. In the remaining patients, mean transmitral gradient and PHT valve area before discharge was 5.2+/-3 mmHg and 2.5 cm2. No patients had more than trivial mitral regurgitation. During the follow-up two patients had to be reoperated. Patients with poor immediate (2 patients) or medium term results (2 patients), had a mean echocardiographic score of 12.24, while patients with a satisfactory medium term outcome had a mean score of 7.27 (p<0.001). CONCLUSIONS: Intraoperative TEE may guide the surgeon in the assessment of valvuloplasty. However the absence of mitral regurgitation after repair and at discharge cannot predict the medium term results, which are related to the degree of the disease of the mitral valve.

Antibiótico profilático em cirurgia ginecológica / Prophylactic antibiotic in gynecologic surgery

Os autores fazem uma revisao sobre muitos aspectos ligados ao uso de antibióticos profiláticos em histerectomia. Através de um estudo no Hospital Sao Lucas envolvendo 504 casos de pacientes submetidas a histerectomia no período de cinco anos, concluem, por dados estatísticos, que a administraçao de antibiótico profilático deve ser uma prática rotineira em histerectomia.

Profilaxia da cefaléia pós-punçäo da dura-máter com agulha de peridural pelo uso de soluçäo salina hipertônica a 1,5% / Headache prophylaxis after post-dural puncture with epidural needle by the use of hypertonic solutions at 1.5%

A cefaléia pós-punçäo inadvertida da dura-máter com agulha de peridural é extremamente freqüente e de difícil e controvertido tratamento, sendo de suma importância a prevençäo de seu aparecimento. Entre as medidas profiláticas destaca-se a hidrataçäo, que objetiva uma maior produçäo liquórica. Uma vez que soluçöes salinas isotônicas acarretam a retençäo de água, o uso de soluçöes hipertônicas provocaria hiper-hidrataçäo. Tal fato levaria a uma maior formaçäo de líquido cérebro-espinhal com restabelecimento do equilíbrio hidrodinâmico liquórico que evitaria o aparecimento da cefaléia. Foram estudados 17 casos de perfuraçäo inadvertida da dura-máter com agulha de Tuohy calibre 15 ou 18, em pacientes ASA I ou II, sendo 10 mulheres e sete homens, com idades entre 19 e 65 anos, aos quais foi administrado por via venosa, um litro de soluçäo salina a 1,5%, diariamente, no pós-operatório imediato e nos três dias subseqüentes. Näo foi feita qualquer recomendaçäo, a näo ser o decúbito dorsal sem travesseiro por 24 horas às pacientes obstétricas, por razäo de rotina do serviço. As cirurgias distribuíram-se entre obstétricas (4), anorretais (6), ortopédicas (2), herniorrafias (2), urológicas endoscópicas (2) e apendicectomia (1). Nos primeiros nove pacientes foram tomadas, diariamente, as seguintes medidas: pressäo arterial, pulso, diurese de 24 horas, densidade urinária, sódio, potássio e cloro plasmáticos, hematimetria, hematócrito e hemoglobinemia. Näo houve alteraçäo em qualquer dos parâmetros estudados que inviabilizassem o método. Dois dos 17 pacientes (11,76%) apresentaram cefaléia pós-punçäo dural lombar típica, ambos do sexo feminino. Uma paciente com 23 anos submetida a cesariana, que sofreu perfuraçäo com agulha 18, ...