Heterotopic transplantation of glycerin-preserved trachea: effect of respiratory epithelium desquamation on acute rejection

An effective preservation method and decreased rejection are essential for tracheal transplantation in the reconstruction of large airway defects. Our objective in the present study was to evaluate the antigenic properties of glycerin-preserved tracheal segments. Sixty-one tracheal segments (2.4 to 3.1 cm) were divided into three groups: autograft (N = 21), fresh allograft (N = 18) and glycerin-preserved allograft (N = 22). Two segments from different groups were implanted into the greater omentum of dogs (N = 31). After 28 days, the segments were harvested and analyzed for mononuclear infiltration score and for the presence of respiratory epithelium. The fresh allograft group presented the highest score for mononuclear infiltration (1.78 ± 0.43, P <= 0.001) when compared to the autograft and glycerin-preserved allograft groups. In contrast to the regenerated epithelium observed in autograft segments, all fresh allografts and glycerin-preserved allografts had desquamation of the respiratory mucosa. The low antigenicity observed in glycerin segments was probably the result of denudation of the respiratory epithelium and perhaps due to the decrease of major histocompatibility complex class II antigens.

Estudio experimental de técnicas de fijación testicular / Experimental study on orchipexy

La fijación testicular se realiza para prevenir la torsión del órgano y en la corrección de la criptorquidia.Se han utilizado para ello diversas técnicas,persistiendo discordancia respecto a cúal es la mejor,con menor daño testicular.Este estudio se realizó para comparar la fijación y el grado de lesión testicular con distintas técnicas quirúrgicas,utilizando dos tipos de sutura.Cuarenta ratas adultas de la raza Wistar,anestesiadas con eter etílico se sometieron a la incisión del escroto y exposición de ambos testículos.Se definieron en forma aleatoria cuatro grupos:grupo 1(n=10)fijación con un punto único,grupo 2(n=10)al que se fijó el testículo con dos puntos,grupo 3(n=10)en el que el testículo se fijó con tres puntos.En la mitad de los animales fue utilizado Vicryl 5-0,y en le resto se utilizó Mersilene 5-0,en el grupo 4 (n=10)el testículo se colocó en la bolsa sabdártica sin puntos de sutura.El testículo contralateral no tratado fue utilizado como control.Todos los animales se sacrificaron a los 30 días,evaluándose el grado de fijación macroscópica,eltamaño del testículo,y las alteraciones microscópicas del mismo.Todos los animales completaron el período previsto de observación.Se observó una diferencia significativa de la fijación entre los grupos(p<0,0038):los animales del grupo 1 presentaron una fijación menor respecto a los otrso grupos.Entre los grupos 2,3 y 4 no se observó una diferencia significativa en la fijación,tampoco hubo diferencia entre los animales del mismo grupo suturados con vicryl o mersilene.No se observaron alteraciones inflamatorias testiculares estadísticamente significativas entre los grupos ni entre los animales del mismo grupo fijados con las dos suturas.La fijación testicular con 2 o 3 puntos en la bolsa subdártica es superios a la realizada con un punto único.Esta última provoca alteraciones semejantes a las encontradas con las otras técnicas,que produce significativamente menor fijación

Atherosclerosis and acute arterial thrombosis in rabbits: a model using ballon desendothelization without dietary intervention

Acute thrombosis can be induced in rabbits by a triggering protocol using Russell's viper venom and histamine given after 8 months of a 1 per cent cholesterol diet and balloon desendothelization. In the present study, we tested the hypothesis that aortic desendothelization performed 4 months before the triggering protocol without a high cholesterol diet is a highly effective and less expensive way of producing arterial atherosclerosis and thrombosis. Nineteen male New Zealand white rabbits on a normal diet were studied. The control group (N = 9) received no intervention during the 4-month observation period, while the other group (N = 10) was submitted to aortic balloon desendothelization using a 4F Fogarty catheter. At the end of this period, all animals were killed 48 h after receiving the first dose of the triggering treatment. Eight of 10 rabbits (80 per cent) in the balloon-trauma group presented platelet-rich arterial thrombosis while none of the animals in the control group had thrombus formation (P<0.01). Thus, this model, using balloon desendothelization without dietary manipulation, induces arterial atherosclerosis and thrombosis and may provide possibilities to test new therapeutic approaches.

Clastogenic effect of cisplatin on Wistar rat bone marrow cells

The clastogenic effect of the drug cis-diamminedichloroplatinum II (cisplatin, CDDP) was investigated in Wistar rat bone marrow cells. Male rats, 3 per treatment time, aged months and weighing 250-350 g were injected intraperitoneally with 6.0 mg/Kg CDDP solution, and the control group received isotonic saline. The animals were sacrificed 6, 12, 18, 24 and 48h after the injection. the chromosome preparation was obtained from bone marrow cells. Chromatid and chromosome aberrations were investigated in 300 metaphases per animal. A significant increase in number of chromosome aberration was observed from 6 to 24h, the majority being of the break and gap type. After 48 h a progressive reduction was observed, without differences from the negative control. These date confirm the mutagenic effect of CDDP in rats demonstrated for mice bone marrow by micronuclei assay, for murine ovary cells and mice spermatocytes

Placental bed lesions and infant birth weight in hypertensive pregnant women

Sixty pregnant women with systemic arterial hypertension, whose pregnancies were interrupted by cesarean section at the Maternity Ward of Hospital de Clínicas de Porto Alegre between May 1989 and October 1990, were examined. Specimens of the placental bed were collected by biopsy and the presence of acute atheromatosis and/or fibrinoid necrosis was investigated. The patients were divided into two groups according to the presence or absence of vascular lesions. The biopsy findings of the placental bed were compared with adequate weight at birth related to gestational age, and to the following clinical parameters of the mother: arterial blood pressure, serum creatinine, serum uric acid and proteinuria. Twenty-seven (45 percent) patients presented vascular lesions in the placental bed compatible with acute atheromatosis and/ or fibrinoid necrosis. The presence of vascular changes in the placental bed correlated significantly to diminished weight of the newborn, in terms of the mean weight and in terms of small-for-gestational-age infants, non-nephrotic proteinuria (>=300 mg/24h) and increased levels of uric acid (>=5.5 mg/dl)

O papel da biópsia renal percutânea no transplante renal / The value of percutaneous renal biopsy in kidney transplantation

A biópsia renal percutânea (BRP) vem sendo utilizada como padräo-ouro para o diagnóstico das disfunçöes renais pós-transplante renal. OBJETIVO. Avaliar o papel atual da BRP como modificadora do diagnóstico e conduta nas disfunçöes renais agudas (DRA) pós-transplante renal. MÉTODOS. Foram estudados 67 pacientes tranplantados renais como disfunçöes renais agudas submetidos a 95 biópsias válidas feitas à beira do leito, sem complicaçöes maiores. RESULTADOS. Foi observado discordância entre o diagnóstico clínico e o patológico em 28 ocasiöes (29,5 por cento). Em 36 situaçöes (37,9 por cento) os resultados dos exames histopatológicos levaram a mudanças no manejo dos pacientes. Entre essas modificaçöes destacam-se: suspensäo do pulso de esteróides (oito casos); nefrectomia do enxerto renal (oito casos); suspensäo ou diminuiçäo da dosagem de ciclosporina (seis casos); início de pulso de esteróides (cinco casos) e início de antibioticoterapia por pielonefrite aguda em quatro casos. O uso de rins de doadores cadavéricos esteve significativamente associado a uma freqüência aumentada de biópsia renais (p < 0,05). CONCLUSAO. Esses resultados demonstram que, apesar da existência de métodos menos invasivos, a BRP permanece sendo um método indispensável no manejo do paciente transplantado renal com DRA