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Biomedical subjects

J Nauta

Publications and source records attributed to J Nauta.

At least 55 records · Page 3Linked to original sources
PubMed1991

Biochemical parameters of bone turnover during ten days of bed rest and subsequent mobilization.

Immobilization is associated with increased bone resorption. To investigate the early onset of increased bone resorption, we evaluated 14 patients who were immobilized for 10 days because of lumbar disc protrusion. The fasting urinary hydroxyproline/creatinine ratio increased significantly after four days (P less than 0.01), reached a peak after 10 days (16.4 +/- 3.3 mumol/mmol, 27.6 +/- 8.8 mumol mmol, P less than 0.01) and returned slowly to baseline values after mobilization. The fasting urinary calcium creatinine ratio followed a similar pattern. Serum calcium and phosphate increased during immobilization (P less than 0.01). Serum 1,25-dihydroxyvitamin D decreased significantly during immobilization (98 +/- 33 pmol/l vs. 79 +/- 36 pmol/l, P less than 0.05), and reached a nadir one week after mobilization (P less than 0.01). We conclude that there is an early significant increment in resorption parameters, with a slow return during the mobilization period. Serum 1,25-dihydroxyvitamin D is suppressed as a result of the increased serum calcium and serum phosphate levels.

Adult↗
PubMed1991

Forced hydration prior to renography in children with hydronephrosis. An evaluation.

We have developed a method of diuretic renography for the assessment of upper urinary tract obstruction in children. A maximal diuresis under standardised conditions is obtained by forced intravenous hydration over a 2-h period prior to renography. We evaluated the predictive value of this method for the clinical and functional outcome in 73 children with apparent unilateral pelviureteric junction obstruction. The predictive value of a non-obstructive pattern was 94%, while the predictive value of an obstructive pattern could not be assessed accurately because the patients concerned subsequently underwent operation. The method is safe and reliable and offers advantages over conventional diuretic renography.

Adolescent↗
PubMed1991

Cyclandelate in diabetic neuropathy. A double-blind, placebo-controlled, randomized, cross-over study.

Cyclandelate has the ability to improve the rheological properties of the blood and therefore may improve blood supply of peripheral nerves. Previous studies in diabetic neuropathy have shown beneficial effects of the drug. We performed a double-blind, placebo-controlled, cross-over study in 40 diabetic patients with cyclandelate in a dose of 1600 mg daily. Motor and sensory nerve conduction velocities, late responses, thermal discrimination thresholds, vibration perception thresholds and pain scores were studied. We were not able to show any positive effect of the drug and therefore conclude that cyclandelate is not effective in the treatment of diabetic neuropathy.

Adult↗
PubMed1990

Accuracy and interobserver variation in the interpretation of computed tomography in solitary brain lesions.

The clinical data and computed tomographic findings of 64 patients with solitary supratentorial brain lesions were presented to two panels of six experienced clinicians. The diagnoses predicted by these clinicians were compared with each other (interobserver variation) and with the definite diagnosis, which in almost all cases was based on histologic examination of the involved tissue (validity of predicted diagnosis). The interobserver agreement was only moderate. The predicted diagnoses agreed with the definite diagnoses in only 57% of cases. A high number of errors were made in distinguishing between high-grade and low-grade glioma and between high-grade glioma and cerebral metastasis, and in the detection of primary cerebral lymphoma. Possible implications of these findings for clinical practice are discussed.

Adult↗
PubMed1990

Stenting of the ureterovesical anastomosis in pediatric renal transplantation.

From January 1985 to July 1989, 36 children received a renal transplant at our hospital. Their ages ranged from 2 to 18 years. All patients had a standard neoureterocystostomy according to Lich-Grégoir. In the first 18 patients, no transanastomotic stent was placed. In the latter 18, a transanastomotic stent with or without suprapubic bladder drainage was performed. In the nonstented group, six severe urological complications occurred, two of which eventually resulted in loss of the transplant. In the stented group, only one severe urological complication occurred. No kidneys in this group were lost due to urological complications. The number of urinary tract infections in the nonstented group was the same as in the stented group.

Adolescent↗
PubMed1990

Transplacental induction of membranous nephropathy in a neonate.

We report a case of renal failure in a newborn infant due to membranous glomerulonephritis. The patient was anuric in the first 3 weeks of life, after which renal function recovered. The serum of the mother contained IgG antibodies which reacted with tubular brush borders and glomeruli of adult and fetal human kidneys. Reactivity with renal epithelium from human kidneys was detected. We suggest that a transplacental, passive Heymann nephritis-like mechanism was the pathogenesis of the neonate's symptoms, although the antigen(s) involved was shown not to be gp 330 or any of the renal antigens known to be involved in experimental nephropathies.

Adult↗
PubMed1990

Some introductory remarks on acupuncture in dentistry.

In general two different types of acupuncture are used in dentistry, Traditional Chinese Acupuncture and Acupuncture according to Dr. Voll. Both use imaginary lines, called channels, according to theories of Traditional Chinese Medicine. However fundamental differences between the two types of acupuncture exist.

Acupuncture Therapy↗
PubMed1989

Vaginal sensitivity to electric stimuli: theoretical and practical implications.

Vaginal sensitivity was investigated in a group of 60 volunteers by means of an electric stimulus and under nonerotic conditions. In comparison to the dorsum of the hand, the genital area has a low sensitivity for electric stimuli (p less than 0.001). Of the genital area, the vaginal wall measured 2 to 4 cm from the vaginal introitus was found to be very insensitive (p less than 0.05). Within the vaginal wall a relatively sensitive position to electric stimuli could be detected at the "12-hr position" (the anterior vaginal wall) (p less than 0.001). The study provides data underscoring previous anatomical and clinical research findings regarding the sensitivity of the anterior vaginal wall. The inefficiency of coitus for inducing female orgasm is discussed.

Adolescent↗
PubMed1989

Adenoid cystic carcinoma of the salivary glands: clinicopathological survey of 51 patients.

A clinicopathological study of 51 cases of adenoid cystic carcinoma in the head and neck region seen over a period of 20 years is presented. The correlation between various histological features and their impact on the results is attempted. Longterm results with respect to loco-regional recurrences, distant metastases and survival with various modalities of therapy are presented. Although this is a small series, radical surgery in keeping with the aim of avoiding undue mutilation, thus preserving the quality of life, followed by a full course of radiotherapy has been the mainstay of treatment and the results here presented justify this approach.

Adult↗
PubMed1989

Palliative care for brain metastases of solid tumour types.

Prognostic factors for survival were analyzed retrospectively in 214 patients with brain metastases of the solid tumour type. The most frequent neurological signs and symptoms at diagnosis of cerebral involvement were headache-nausea-vomiting and focal weakness. Similar numbers of patients were found to have solitary metastasis and multiple lesions. Non-small cell lung cancer, small cell lung cancer, breast cancer, melanoma, and renal cell cancer comprised the majority of the primaries. Most patients received high-dose corticosteroids, while in a third, anticonvulsant agents were administered. Of 157 patients treated with radiation alone, or surgery with or without radiation, 110 experienced alleviation of symptoms or stabilisation of the disease. In 38 patients with a solitary lesion, craniotomy was carried out, either with or without postoperative radiation; the latter group showed the longest survival with a median of 37 wk. The remaining group of 73 patients with one brain metastasis had a median survival of only 15 wk. The 69 patients with multiple lesions who had been irradiated had a median survival of 15 wk, while that for 34 untreated patients was 7 wk. A short median survival of 11 and 13 wk, respectively, was observed in patients with concurrent progressive extracerebral disease and in those with progressive neurological symptoms regardless of treatment. It is concluded that in patients with a solitary brain metastasis without progressive extracerebral disease surgery should be considered the treatment of first choice aiming at a long-term survival with a good quality of life.

Adrenal Cortex Hormones↗
PubMed1989

Comparison of two different high doses of metoclopramide in the prevention of chemotherapy-induced emesis.

A randomized double-blind study was conducted to compare the anti-emetic efficacy of 1 mg/kg vs 2 mg/kg metoclopramide, administered 5 times over a period of 8.5 h in 50 cancer patients treated with platinum-containing regimens (cisplatin, ethylenediamine platinum II malonate or spiroplatin). Twenty-six patients were treated with combination chemotherapy, mainly consisting of cisplatin and 5-fluorouracil. No statistically significant differences were observed with respect to the protection against nausea and vomiting between the two dose levels of metoclopramide. However, in the group of patients who received a high dosage of cisplatin (70-100 mg/m2), or ethylenediamine platinum II malonate (800-900 mg/m2), there was a significant difference in nausea and vomiting between patients who had and those who had not received prior chemotherapy, most probably due to anticipation. No difference in the severity of the side effects was observed with the 2 metoclopramide dose levels. Considerable interpatient variation was present in serum metoclopramide levels. No clear correlation was observed between serum metoclopramide levels and prevention of platinum-induced emesis. We conclude that 1 mg/kg of metoclopramide is just as effective as 2 mg/kg as an anti-emetic agent in patients receiving platinum-based chemotherapy, and that metoclopramide serum levels are not related to the anti-emetic effect.

Adult↗
PubMed1988

Pupillary light reflex and quantitative sensory and motor neural function tests in diabetic patients.

In 29 diabetic subjects with or without symptoms of diabetic peripheral and autonomic neuropathy, the association between the pupillary light reflex (the latency of the constriction of the pupil) and various sensory and motor neural measurements, duration of diabetes and quality of glycaemic control was evaluated. Compared with normal subjects the latency of the constriction reaction of the pupil was significantly prolonged in the group of diabetics (mean +/- SEM: 236.3 +/- 5.8 ms versus 210.5 +/- 3.7; P less than 0.001). Thermal discrimination thresholds were positively correlated with the latency of the constriction reaction of the pupil (r = 0.43, P less than 0.025). Vibratory perception threshold, motor nerve conduction velocity of the peroneal nerve, H-M interval of the Hoffmann reflex and duration of diabetes were not correlated with the constriction latency, whereas glycaemic control showed a weak correlation. It is concluded that there may be a relationship between autonomic (parasympathetic) pupillary dysfunction and peripheral small nerve fibre dysfunction.

Adult↗
PubMed1988

Biventricular performance during volume loading in patients with early septic shock, with emphasis on the right ventricle: a combined hemodynamic and radionuclide study.

The cardiac response to a rapid volume infusion was studied in 18 patients with septic shock accompanied by pulmonary hypertension. Right and left ventricular ejection fractions were measured, and right and left ventricular volume indices were calculated from ejection fractions and stroke volumes before and 30 minutes after the start of the infusion. Responders (13 patients) showed an increase in stroke volume index (SVI) as a result of a mean 30% increase in right ventricular end-diastolic volume index (RVEDVI) and a mean 17% increase in left ventricular end-diastolic volume index (LVEDVI) during volume loading. In the nonresponders (five patients) fluid loading resulted in a decreased or unchanged SVI; this was accompanied by a 7% increase in RVEDVI but no change in LVEDVI, although both the central venous pressure and pulmonary capillary wedge pressure increased. At baseline, nonresponders differed from responders as evidenced by a high central venous pressure and RVEDVI but a lower mean arterial pressure: thus, right ventricular coronary perfusion pressure was lower and right ventricular wall stress may have been higher. Mean pulmonary artery pressure did not differ between the groups. Our data suggest that in some patients with septic shock volume loading does not result in increased forward flow because of right ventricular failure associated with pulmonary hypertension and coronary hypotension.

Fluid Therapy↗
PubMed1988

Renal functional impairment in preterm neonates related to intrauterine indomethacin exposure.

Renal function was measured during the first 4 postnatal days in 9 preterm neonates (gestational age 26.2 to 31 wk) exposed to indomethacin during the last 2 days of pregnancy (group I). The data were compared to those obtained from nine control neonates (gestational age 28 to 34.5 wk) (group II). Five of the nine neonates in group I were markedly edematous at birth, none of group II were edematous. Urine production in group I was low (32.2 +/- 16.8 ml/kg.day on day 1 increasing to 68.6 +/- 21.4 ml/kg.day on day 4) and differed significantly from group II [75.2 +/- 26.8 ml/kg.day on day 1 increasing to 84.8 +/- 20.9 ml/kg.day on day 4 (p less than 0.001)]. Fluid intake was adapted to urine production when necessary. A continuous inulin infusion was started directly after admission and continued for 5 days. Renal function was evaluated for 3 consecutive days after at least 48 h of insulin infusion. The values of the inulin clearance, serum creatinine, urine osmolarity, osmolar clearance, and free water clearance were stable in both groups during the study period. Inulin clearance was lower in group I than in group II (p less than 0.001), whereas serum creatinine was higher in group I than in group II (p less than 0.0001). Urine osmolarity was higher in group I (p less than 0.01), whereas osmolar clearance and free water clearance were lower in group I (p less than 0.02, respectively, p less than 0.01). There was no difference in fractional sodium excretion between the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1987

The immediate effect of nitroglycerin on total body blood volume distribution in patients with congestive heart failure: a non-invasive study.

The effect of sublingually administered nitroglycerin (0.5 mg) on distribution of blood volume in 16 patients with congestive heart failure (NYHA class II and III), randomly assigned to placebo (N = 8) or nitroglycerin (N = 8) was studied 20 minutes after in vivo labelling of red blood cells with 99m-Tc pertechnetate. Count rates over thorax, abdomen and legs were collected with a large field gamma camera and expressed as percentage changes of baseline value. Changes in count rates, averaged for 5, 10 and 15 minutes after drug administration showed a significant decrease in the nitroglycerin group as compared to the placebo group over the thorax (mean 5%, P less than 0.01) and over the liver (mean 5%, P less than 0.05) and a significant increase over the abdomen (mean 4%, P less than 0.01) and the legs (mean 9%, P less than 0.01). After nitroglycerin, the changes in pulmonary activity were variable and did not differ from the placebo group. These results indicate that nitroglycerin causes a redistribution of blood volume in patients with congestive heart failure. An increase in the vascular capacitance in the abdomen and legs may be responsible for a decrease of blood volume of the thorax and the liver in these patients.

Abdomen↗
PubMed1987

Volume expansion, dobutamine and noradrenaline for treatment of right ventricular dysfunction in porcine septic shock: a combined invasive and radionuclide study.

The purposes of the present study were 1) to explore if volume loading in combination with dobutamine or noradrenaline would be superior to volume loading alone in the treatment of right ventricular (RV) dysfunction in septic shock complicated by acute pulmonary hypertension and 2) to determine whether noradrenaline would be superior to dobutamine because of its vasoconstrictor effects on the peripheral circulation, resulting in increased RV coronary perfusion pressure. Experiments were performed on 21 anesthetized, ventilated pigs. Gated blood pool studies and hemodynamic measurements were performed simultaneously. All animals were given 3-4 X 10(8)/kg live E. coli bacteria, resulting in an abrupt increase in pulmonary arterial pressure and a decrease in arterial pressure, cardiac output, and RV ejection fraction. Right ventricular end-systolic volume was unchanged; RV end-diastolic volume and RV coronary perfusion pressure fell. After randomization, the control group (I, n = 5) was subjected to volume loading, and treatment groups (each n = 8) received volume loading in combination with dobutamine (group II, 5-10 micrograms/kg/min) or noradrenaline (group III, 0.25-0.50 micrograms/kg/min). In contrast to volume loading alone, dobutamine and noradrenaline increased cardiac output and RV ejection fraction, but only noradrenaline restored mean arterial pressure. Noradrenaline improved RV contractility, as judged from the RV end-systolic pressure-volume relationship, probably because it increased the RV perfusion. Thus, noradrenaline in combination with volume loading may be the treatment of choice to improve RV performance in porcine septic shock associated with pulmonary hypertension.

Animals↗