Time-dependent effects of ovarian steroids on tyrosine hydroxylase activity in the limbic forebrain of female rats

Summary In this work, we have studied the time-course of the effects of pharmacological administration of ovarian steroids on tyrosine hydroxylase (TH) activity in the limbic forebrain of ovariectomized rats. Administration of estradiol produced a late decrease in TH activity. This effect was found 24 hours after the last steroid injection, disappearing at 32 hours. It was antagonized by progesterone, since a single injection of this steroid to estradiol-pretreated rats reversed to control values the estradiol-induced decrease. Nevertheless, the administration of progesterone after estradiol treatment caused a short-time decrease in the limbic activity of TH, which was observed 4 hours after the last steroid injection, disappearing subsequently. On the other hand, the administration of progesterone alone produced a biphasic effect, with a reduction at 24 hours, followed by an increase at 32 hours. These effects were only observed in the animals non-treated with estradiol, disappearing with a previous treatment with estrogens. Hence, it can be concluded that both ovarian steroids may affect the limbic TH activity. Thus, estradiol produced a late inhibitory effect on the activity of this enzyme, which was antagonized by progesterone. Administration of the last one to estradiol-treated rats produced a short-time inhibitory effect, whereas its administration to non-treated rats produced a late biphasic effect (inhibition followed by stimulation), which was not observed in estradiol-treated rats.     

Role of the health care supervisor in management of a therapeutic milieu.

The health care supervisor responsible for establishing a therapeutic milieu within a traditional hospital organization will have greater success if these suggested management strategies are employed. Decentralizing, improving organizational communication, and clarifying interdisciplinary role relationships are the strategies that support the integration of differing organizational approaches to management.     

Hydrocephalus and cavernoma of the cauda equina

The association of a tumor of the cauda equina and hydrocephalus is unusual. We report a case of hydrocephalus with normal pressure associated with an equally rare affliction, a cavernous angioma of the cauda equina, which regressed after surgical ablation. The physiological mechanism involved is discussed.     

Estimation of salt intake by urinary sodium excretion in a Portuguese adult population and its relationship to arterial stiffness.

BACKGROUND: Portugal has one of the highest mortality rates from stroke, a high prevalence of hypertension and probably a high salt intake level. AIM: To evaluate Portuguese salt intake levels and their relationship to blood pressure and arterial stiffness in a sample of four different adult populations living in northern Portugal. METHODS: A cross-sectional study evaluating 24-hour urinary excretion of sodium (24 h UNa+), potassium and creatinine, blood pressure (BP), and pulse wave velocity (PWV) as an index of aortic stiffness in adult populations of sustained hypertensives (HT), relatives of patients with previous stroke (Fam), university students (US) and factory workers (FW), in the context of their usual dietary habits. RESULTS: We evaluated a total of 426 subjects, mean age 50 +/- 22 years, 56% female, BMI 27.9+/-5.1, BP 159/92 mmHg, PWV 10.4+/-2.2 m/s, who showed mean 24h UNa+ of 202 +/- 64 mmol/d, corresponding to a daily salt intake of 12.3 g (ranging from 5.2 to 24.8). The four groups were: HT: n = 245, 49 +/- 18 years, 92% of those selected, 69% treated, BP 163/94 mmHg, PWV 11.9 m/s, 24 h UNa+ 212 mmol/d, i.e. 12.4 g/d of salt); Fam: n = 38, 64 +/- 20 years, 57 % of those selected, BP 144/88 mmHg, PWV 10.5 m/s, 24 h UNa+ 194 mmol/d, i.e. 11.1 g/d of salt; US: n = 82, 22 +/- 3 years, 57% of those selected, BP 124/77 mmHg, PWV 8.7 m/s, 24h UNa+ 199 mmol/d, i.e. 11.3 g/d of salt; FW: n = 61, 39 9 years, 47% of those selected, BP 129/79 mmHg, PWV 9.5 m/s, 24 h UNa+ 221 mmol/d, i.e. 12.9 g/d of salt. The ratio of urinary sodium/potassium excretion (1.9 (0.4) was significantly higher in HT than the other three groups. In the 426 subjects, 24h UNa+ correlated significantly (p < 0.01) with systolic BP (r = 0.209) and with PWV (r=0.256) after adjustment for age and BP. Multivariate analysis showed that BP, age and 24h UNa+ correlated independently with PWV taken as a dependent variable. CONCLUSIONS: Four different Portuguese populations showed similarly high mean daily salt intake levels, almost double those recommended by the WHO. Overall, high urinary sodium excretion correlated consistently with high BP levels and appeared to be an independent determining factor of arterial stiffness. These findings suggest that Portugal in general has a high salt intake diet, and urgent measures are required to restrict salt consumption in order to prevent and treat hypertensive disease and to reduce overall cardiovascular risk and events.     

Bone disease in primary biliary cirrhosis: Lack of association with distal renal tubular acidosis

Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.     

Postangioplasty renal artery thrombosis treated intraluminally with thrombolysis. A case report]

The authors present the clinical case of a 31 year female with systemic vascular hypertension secondary to a 65 percent unilateral fibromuscular renal artery stenosis. The centellographic study demonstrated hypoperfusion on the right kidney and serious functional damage; the patient was subject to intraluminal renal angioplasty resulting in right renal arterial thrombosis, which was treated successfully with intra-arterial and intravenous streptokinase infusion. Following the thrombotic therapy, recanalization of the thrombosed artery and normal renal excretion of the contrast substance was observed.     

The effects of chondroitinase ABC on the rabbit intervertebral disc. A roentgenographic and histologic study

A series of intradiscal injections of chondroitinase ABC was performed in 31 young adult rabbits. Roentgenograms were taken immediately postinjection and were repeated at two, three, five, six, seven, or nine days after injection. All had roentgenographic evidence of disc space narrowing at all stages after the injection. Histologic evaluation of safranin-O fast green-stained sections indicated degradation of proteoglycans in the annulus fibrosus of chondroitinase ABC-injected discs. The cells of the chondroitinase ABC-injected discs, the end plates, and the growth-plate areas of adjacent vertebral bodies appeared unaffected.     

Traumatic aneurysm of the internal carotid artery: a late finding presenting as a mass in the sphenoid sinus.

We describe a case of a traumatic aneurysm of the cavernous portion of the internal carotid artery in a patient who had had craniofacial trauma 12 years before. MR and CT revealed a mass in the sphenoid sinus thought to be unrelated to the patient''s symptoms. Carotid angiography gave the correct diagnosis.     

Heparin effect on ionised calcium concentration

The effect of heparin on plasma ionised calcium was studied by adding it in increasing amounts to whole blood from 10 normal subjects. There was no significant change in ionised calcium from the addition of 1 U/ml but a significant fall of 0.02 mmol/1 when 2 U/ml were added and a progressive further fall with increasing concentrations. Heparin from three different manufacturers produced similar results. The effect of heparinisation in vivo was studied during regular haemodialysis on 10 patients with chronic renal failure. Following intravenous injection of 10000 U of heparin there was a consistent and significant fall averaging 0.03 mmol/l.