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J Bach

Publications and source records attributed to J Bach.

At least 19 recordsLinked to original sources

Urokinase and plasminogen activator-inhibitor (PAI-1) status in primary ovarian carcinomas and ovarian metastases compared to benign ovarian tumors as a function of histopathological parameters.

Ninety-eight patients with histologically confirmed ovarian tumors (77 primary ovarian carcinomas of stages T1 to T3 according to the postoperative histopathological classification pTNM classification, 14 ovarian metastases of various origins and seven benign ovarian tumors) were investigated with regard to the concentration of urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor (PAI-1) in membrane extracts of tumors. The results were correlated with the clinical course and with histopathological findings. With more advanced stage of primary ovarian carcinomas, there was a highly significant rise in the membrane concentrations of both uPA and PAI-1. However, increasing dedifferentiation of the tumors correlated only with uPA, but not with PAI-1. There was no correlation between the number of steroid receptors for estradiol and progesterone and the content of uPA or PAI-1 in the primary ovarian carcinomas. In the 14 ovarian metastases of different origins incluced in the study, the contents of uPA and PAI-1 were comparable to those of primary ovarian carcinomas. Compared with the malignant ovarian tumors, the median uPA and PAI-1 concentrations in the membrane fraction were 2.5-6 fold lower (highly significant) in the group of seven benign tumors. A cut-off value of 4.8ng/mg pellet protein for a prognostically favorable (< 4.8) or unfavorable course (> 4.8) could be determined for uPA (p = 0.0392) but not for PAI-1 on the basis of the Kaplan and Meier survival curves in the malignant primary ovarian carcinomas.

Adult

Radio Frequency Signals in Jupiter's Atmosphere

During the Galileo probe's descent through Jupiter's atmosphere, under the ionosphere, the lightning and radio emission detector measured radio frequency signals at levels significantly above the probe's electromagnetic noise. The signal strengths at 3 and 15 kilohertz were relatively large at the beginning of the descent, decreased with depth to a pressure level of about 5 bars, and then increased slowly until the end of the mission. The 15-kilohertz signals show arrival direction anisotropies. Measurements of radio frequency wave forms show that the probe passed through an atmospheric region that did not support lightning within at least 100 kilometers and more likely a few thousand kilometers of the descent trajectory. The apparent opacity of the jovian atmosphere increases sharply at pressures greater than about 4 bars.

Journal Article

Murine models of polycystic kidney disease.

The current knowledge of human polycystic kidney disease (PKD)--its morphology as well as the current biochemical and molecular understanding of the disease- has been enormously aided by the existence of a variety of animal models. In mice, several spontaneous mutations have been identified that give rise to PKD. Furthermore, it has been possible to create experimental models of renal cystic disease by genetic manipulation. All these different models have been very informative in studying the role of growth hormones, cell differentiation and hyperplasia, ionic transport, oncogene expression and changes in extracellular matrix (ECM) composition during the development of PKD. Furthermore, they have allowed investigators to test different therapeutic approaches in vivo. This article will review the characteristics of the most common murine models of PKD, some of their current uses and the future role of these animal models in the understanding of human renal cystic disease.

Animals

Rat models of autosomal dominant polycystic kidney disease.

Several rat models of polycystic kidney disease (PKD) have been published. The only rat model of autosomal dominant polycystic kidney disease currently used is the so-called Hannover rat (Han:SPRD cy/+). This model is characterized by a slow progression of uraemia, proteinuria and hyperlipidaemia. Histological changes clearly resemble those seen is human PKD. The localization of Na+/K(+)-ATPase correlating with the phenotype of the cysts--basal in moderately expanded and apical in highly expanded cysts--suggests that the mislocation of the Na+/K(+)-ATPase is involved in the mechanism of cyst expansion rather than formation, and a consequence of cell dedifferentiation rather than an initial event. Of note is a considerable gender difference in disease severity. Disease anticipation or genetic imprinting does not occur. In addition to gender, a number of interventions influence the progression rate: acceleration is noted after unilateral nephrectomy, the induction of acidosis, chloride feeding or an increased protein intake; slowing down of the course occurs after the induction of alkalosis and castration, and after treatment with lovastatin and methylprednisolone. Thus the Han:SPRD cy/+ rat represents the only well-documented rat model of autosomal dominant PKD resembling a number of features of the human disease.

Animals

In vitro formation of cysts derived from a rat model of autosomal dominant polycystic kidney disease.

In this study, we report a model of spontaneous cyst formation in vitro and a procedure to obtain large quantities of cysts from polycystic rat kidney cells. Furthermore, we assess the effects of epidermal growth factor, a modulator of morphogenesis, and of taxol, a stabilizer of microtubules, which has recently been proposed as a useful treatment of human polycystic kidney disease (PKD). It is anticipated that data generated from in vitro studies using cysts from PKD-affected rat kidneys may yield further insights to the pathophysiological and cellular basis of fatal renal cyst formation processes, and may lead to specific therapeutic strategies directed at controlling the growth of cysts, thereby reducing the number of animal tests.

Animals

Effects of the fungicide prochloraz on xenobiotic metabolism in rainbow trout: in vivo induction.

1. Rainbow trout were dosed with prochloraz by i.p. injection of sprayed food pellets. Cytochrome P-450, two P-450-dependent activities, and two conjugase activities were measured in vitro in microsomal or cytosolic fractions. 2. Prochloraz increased cytochrome P-450 in liver, intestine, and pyloric caeca: maximum response occurred at 30-100 mg/kg i.p. In cold conditions, this increase persisted for more than 8 days after injection. 3. Hepatic 7-ethoxycoumarin-O-dealkylase (ECOD) and 7-ethoxyresorufin-O-dealkylase (EROD) were inhibited by prochloraz except in one assay in warm water where they increased. In intestine and pyloric caeca, ECOD and EROD were not detected, even when cytochrome P-450 was increased. 4. UDP-glucuronosyltransferase (1-naphthol as substrate) was unchanged or inhibited after prochloraz dosing. 5. Glutathione-S-transferase (o-dinitrobenzene as substrate), was unchanged or inhibited by prochloraz. 6. The measured level of enzymic activities was the result of induction and inhibition by prochloraz residues. Variations in basal activities and perhaps in prochloraz interactions were due to temperature acclimatization.

Administration, Oral

Effects of the fungicide prochloraz on xenobiotic metabolism in rainbow trout: inhibition in vitro and time course of induction in vivo.

1. Interactions between the fungicide prochloraz and the hepatic cytochrome P-450 of rainbow trout were studied by determination of enzymic activities in vitro using the microsomal fraction, and by kinetic studies. 2. Prochloraz inhibited 7-ethoxyresorufin-O-deethylase (EROD) in vitro. This inhibition was partially non-competitive: the enzyme-substrate-inhibitor (ESI) complex was catalytically active (68% of the activity of the enzyme-substrate complex). 3. Prochloraz in vitro inhibited aldrin epoxidase (AE) by a linear mixed-type mechanism. This inhibition might be high because of high affinity for prochloraz and lack of catalytic activity of the ESI complex. 4. Effects of prochloraz in vivo were studied as a function of time after intraperitoneal injection. Total cytochrome P-450 increased for more than 21 days. 5. EROD increased slightly at day 4 and then returned to control level. Kinetics showed an increase in apparent Km and Vmax. AE was strongly inhibited at day 4 (large increase in apparent Km) and then returned to control level in 21 days. 6. Spectral interactions with aniline showed strong inhibition and recovery to an activated level at day 21.

Animals

Evoked potential assessment: utility in prognosis of chronic head injury.

Brainstem auditory evoked potentials (BAEP) and somatosensory evoked potentials (SSEP) were performed on 29 patients an average of 12.4 months after traumatic brain injury (TBI). The study purpose was to predict long-term outcome in chronic TBI patients by using multimodality evoked potentials (MEP), the Rancho Los Amigos Scale (RLAS), and other clinical parameters. Neither the BAEP nor SSEP correlated significantly with the cognitive level on the RLAS at the MEP study approximately one year after TBI (RLAS1). Only 11.7% of RLAS1 could be predicted by the combined study of BAEP and SSEP. BAEP and SSEP obtained about one year after TBI jointly had a 15% predictive power of the long-term follow-up RLAS score obtained 18 months after performance of the MEP (RLAS2). Stepwise regression analysis showed that the best predictive indicator of the status of long-term outcome was RLAS1 which alone can predict 60% of long-term outcome. The predictive value of combinations of RLAS1 and age improved prediction of long-term outcome to 66.8%, and the combination of RLAS1, age, and SSEP further increased the value to 72%. Perhaps the MEPs were relatively insensitive in reflecting the patient's adaptation to fixed neuronal damage since patients can perform higher cognitive function by adaptation through behavioral modification and cognitive retraining despite little structural improvement. This adaptation would result in a discrepancy between MEP and RLAS scores in the late chronic phase.

Adolescent

Hepatic biotransformation in the buzzard (Buteo buteo) and the Japanese quail (Coturnix coturnix): effect of PCBs.

Hepatic biotransformation was studied in microsomal (cytochrome P-450-dependent monooxygenase activities) and cytosolic (glutathione S-transferase activities) fractions from Japanese quail (Coturnix coturnix) and buzzard (Buteo buteo). Monooxygenase activities were not very different apart from a high 7-ethoxycoumarin de-ethylase activity in quail as compared to buzzard. Glutathione S-transferase activities were higher in quail than in buzzard. DP5 (a commercial mixture of PCBs containing 50% chlorine) produced a marked increase in monooxygenase activity from quail liver. In contrast, no induction was found in buzzard under the same conditions. Glutathione S-transferase activities were not modified in both species.

Animals

The treatment of scoliosis in Duchenne muscular dystrophy.

There are not, as yet, clear indications for the surgical management of scoliosis in Duchenne muscular dystrophy (DMD), taking into account the varying severity of the clinical course. Monitoring the vital capacity can be most important for the indication and timing of surgery. In some cases, delaying surgical intervention with conservative management using spinal braces and wheelchair inserts can permit the restrictive lung syndrome to advance to the point that surgery will be contraindicated. Ten such patients conservatively treated for an average of 5 years exhibited perhaps a slower progression but ultimately an advanced deformity. From a second group of five carefully selected and surgically treated patients, indications for spinal surgery were reviewed. Surgical intervention should be prophylactically undertaken when there is high risk of a rapidly evolving curve with a severe restrictive lung syndrome.

Braces

Positioning, splinting and pressure management of the burned hand: a method.

A splinting procedure to avoid hand and finger deformities in deep dermal and subdermal burns of the hand is presented. The same splint may be used in the healing phase as well as in the rehabilitation period. The method is characterized by a combination of simple materials, active exercises and a teamwork involving the patient and the staff.

Bandages