Search PubMedSearch

Biomedical subjects

J Nauta

Publications and source records attributed to J Nauta.

At least 19 recordsLinked to original sources

Protein intake can not be estimated from urinary urea excretion.

We assessed the relationship between protein intake (calculated from a 3-day prospective dietary diary) and 24-h urinary urea excretion in 37 children with chronic renal failure. Protein intake was not restricted during the investigation period. The 24-h urinary urea excretion correlated poorly with the protein intake estimated from the dietary diary (r = 0.58). We conclude that although it is common practice to assess compliance with a protein-restricted diet in children with chronic renal failure with a dietary diary and 24-h urinary urea excretion, the value of this assessment is questionable.

Adolescent

White matter lesions on magnetic resonance imaging in clinically diagnosed Alzheimer's disease. Evidence for heterogeneity.

In a prospective magnetic resonance imaging (MRI) study we evaluated the prevalence and severity of white matter changes in 29 patients with Alzheimer's Disease (AD) and 24 age-matched healthy elderly, all without cerebrovascular risk factors. The AD patients were divided into two groups according to age at onset of symptoms, one with presenile onset AD (n = 13) and one with senile onset AD (n = 16), who were matched for dementia severity. Signal hyperintensities were rated using a semiquantitative scoring method, separately in the periventricular region (PVH) and in the lobar white matter (WMH), as well as in the basal ganglia (BGH) and in the infratentorial region (ITFH). Cortical atrophy as a parameter of grey matter involvement was rated on a 0 (absent) to 3 (severe) scale. We found PVH, WMH and BGH scores to be significantly higher in senile onset AD patients than in age-matched controls. By means of multiple linear logistic regression we found that PVH, WMH and BGH scores were significantly dependent on the diagnosis of senile onset AD, while the PVH score also showed a significant age dependency. Cortical atrophy did not differ significantly between presenile onset AD and senile onset AD patients. These results indicate that presenile onset AD and senile onset AD patients differ with respect to white matter involvement, but not with respect to grey matter involvement on MRI. Since cerebrovascular risk factors were excluded these findings may indicate that senile onset AD patients display more small vessel involvement (arteriolosclerosis) than presenile onset AD patients, suggesting additional (microvascular) factors for the dementia syndrome in senile onset AD. Our data lend support to the growing body of evidence that AD is heterogeneous, consisting of at least two types. Based on our findings two forms can be distinguished: (i) a 'pure' form of the disease, usually with early disease onset, and no more white matter changes than normal for age; (ii) a 'mixed' form, usually with disease onset later in life, and showing more white matter changes on MRI than normal for age.

Aged

Interleukin-2 induces activation of coagulation and fibrinolysis: resemblance to the changes seen during experimental endotoxaemia.

The administration of Interleukin-2 (IL-2) causes the release or generation of other cytokines such as tumour necrosis factor (TNF) which, by disturbing the anticoagulant properties of the endothelium, may induce a procoagulant state in patients receiving this drug. We therefore evaluated the effects of IL-2 on coagulation and fibrinolysis in 14 patients receiving 12 or 18 x 10(6) IU/m2/d of IL-2 given as a 15 min infusion for 5 d. Blood samples were drawn at short intervals after the first IL-2 infusion. The parameters were analysed by way of analysis for repeated measures (F tests rather than t tests). During the first day, thrombin-antithrombin (TAT) complexes started to increase 2 h after the IL-2 infusion, reaching peak levels at 4 h (n = 14; 11.2 +/- 6.4 micrograms/l v 49.8 +/- 49.2 micrograms/l, P < 0.01). Plasma alpha 2 antiplasmin (PAP) complexes showed a similar pattern rising from a mean baseline value of 17.5 +/- 7.6 nmol/l to 66.8 +/- 47.7 nmol at 4 h (P < 0.01). In four patients the peak of PAP preceeded that of TAT. Tissue plasminogen activator (tPA) rose from a mean baseline value of 4.9 +/- 3.7 micrograms/l to 26.3 +/- 13.5 micrograms/l at 4 h (P < 0.01). Plasminogen-activator-inhibitor-1 (PAI-1) levels increased from 59 +/- 35 micrograms/l to 113 +/- 39 micrograms/l at 6 h (P < 0.01). tPA PAI-1 complexes increased from 0.15 +/- 0.07 to 0.69 +/- 0.21 nmol/l at 6 h (P < 0.01). Our study indicates that IL-2 activates the coagulation and fibrinolytic systems in vivo. The changes resemble the perturbations observed after endotoxin/TNF administration. These abnormalities may play a role in the side-effects induced by IL-2 therapy.

Adult

Protein restriction affects fat intake and serum lipids in children with chronic renal failure.

Cardiovascular complications in patients with chronic renal failure have been associated with the hyperlipidemia present in many of these patients. Since a protein-restricted diet is often prescribed in an attempt to preserve renal function, we performed a randomized controlled study in children with chronic renal failure on the effect of a protein-restricted diet on fat intake and serum lipid profiles. Although total fat intake did not change, we found a lower cholesterol intake and a higher polyunsaturated/saturated fat ratio in the patients with the protein-restricted diet. This is probably caused by the restriction of animal protein which results in the replacement of animal fat by vegetable fat in the protein-restricted group. Moreover, we observed an increase of plasma cholesterol and low-density lipoprotein cholesterol in patients with a normal protein intake which was absent in the protein-restricted group. This suggests a favourable effect of the institution of a protein-restricted diet on lipid intake and plasma profile.

Adolescent

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

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

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

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

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

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

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

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

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

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

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

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