Search PubMed⌕ Search

Biomedical subjects

S Meijer

Publications and source records attributed to S Meijer.

At least 199 records · Page 11Linked to original sources
PubMed1989

Renal handling of technetium-99m DMSA: evidence for glomerular filtration and peritubular uptake.

The finding of an enhanced excretion of [99mTc]dimercaptosuccinic acid (DMSA) in patients with tubular reabsorption disorders prompted us to investigate the role of filtration in the renal handling of [99mTc]DMSA. Our studies in human serum indicated that binding to serum proteins was approximately 90%. Chromatography of human urine and studies in rats showed that the complex was excreted unaltered into the urine. Renal extraction of [99mTc]DMSA in a human volunteer was 5.8%. Continuous infusion of [99mTc]DMSA in 13 individuals with normal renal function gave the following results (mean +/- s.d.): plasma clearance of [99mTc]DMSA 34 +/- 4 ml/min, urinary clearance of [99mTc]DMSA 12 +/- 3 ml/min. The calculated filtered load of [99mTc]DMSA closely resembled the urinary clearance, whereas the plasma clearance was about three times faster. This indicates that peritubular uptake accounts for approximately 65% and filtration for approximately 35% of the renal handling of [99mTc]DMSA.

Animals↗
PubMed1989

Surgical treatment of bronchopulmonary carcinoid tumours.

Based on histopathological characteristics bronchopulmonary carcinoid tumours can be divided into a typical and an atypical variant. Atypical carcinoid tumours often have regional lymph node metastases. A differentiation between the two types of tumours cannot be made preoperatively. A total of 23 patients underwent resectional therapy for carcinoid tumours of the lung. Eleven underwent pneumonectomy, eight patients lobectomy and three patients had bilobectomy. Segmental resection was performed in one patient. One patient died in the postoperative period. During the follow-up period, ranging from 5 to 22 years (median 11 years), neither local recurrences nor metastatic spread was observed. In eight patients the tumour was classified as the atypical variant. There was no correlation between the size of the tumour and the presence of regional lymph node metastases. All tumours with lymph node metastases were classified as atypical carcinoids. As in other studies, our data suggest that treatment based on standard resectional procedures is to be preferred for bronchopulmonary carcinoids since a preoperative distinction between the typical and atypical variants is as yet not possible.

Adult↗
PubMed1988

Absence of relation between nutritional parameters and renal function in non-seminomatous testicular cancer patients.

Earlier studies revealed that renal function is reduced in non-cancer patients with a malnutritional status. We have studied the effect of nutritional status on renal function in 46 patients with disseminated non-seminomatous testicular cancer treated with combination chemotherapy including cis-diammine dichloroplatinum (cDDP) according to the Einhorn regimen. The renal function was expressed as glomerular filtration rate (GFR), effective renal plasma flow (ERPF), and filtration fraction (FF) measured by radioisotope infusion methods. Nutritional assessment of the patients was performed by means of three nutritional parameters: weight-for-height index (WHI), creatinine height index (CHI), and serum albumin concentration (Salb). The patients were also divided into two groups: group 1, patients with a sufficient nutritional status, defined as patients with only one abnormal nutritional parameter or none at all (n = 30); group 2, patients with an insufficient nutritional status, defined as patients with two or three abnormal nutritional parameters (n = 16). Median values of WHI, CHI and Salb in group 2 patients were significantly lower than the median values in group 1. Before treatment no correlation was found between the individual nutritional parameters and GFR, ERPF and FF respectively. The median GFR, ERPF and FF of both group 1 and group 2 did not differ significantly. Although the renal function of the total group of patients was reduced as a result of cDDP, this reduction was not influenced by the individual parameters and not higher in the group with an initially insufficient nutritional status. In this study no relation was found between nutritional status and renal function of patients with disseminated non-seminomatous testicular cancer.

Adolescent↗
PubMed1988

Impairment of organ function after oral ingestion of refined petrol.

After oral ingestion of 600 ml of refined petrol a 23-year-old male developed multiple organ failure. Acute renal insufficiency due to nephrotoxic tubular necrosis requiring hemodialysis was a major manifestation. Moreover, respiratory failure, seizures, hemolysis, disseminated intravascular coagulation, liver damage and erosions of mucous membranes occurred. The patient subsequently recovered completely. In spite of the poor absorption from the gastrointestinal tract and the high first-pass effect in the liver, massive petrol intoxication may lead to reversible multisystemic lesions.

Acute Kidney Injury↗
PubMed1988

Effect of metoclopramide on dopamine-induced changes in renal function in healthy controls and in patients with renal disease.

1. The effects of intravenous metoclopramide on baseline values and dopamine dose-response curves for renal haemodynamics and natriuresis were investigated in healthy volunteers and patients with renal disease. 2. Dopamine infusion alone, in doses ranging from 0.25 to 8 micrograms min-1 kg-1, resulted in a dose-dependent increase in effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) with a fall in filtration fraction (FF) in eight hydrated healthy volunteers and, to a lesser degree, in 12 patients with renal disease. An increase in natriuresis (urinary excretion of sodium, UNa+V), fractional excretion of sodium (FENa+) and diuresis (urine flow rate, UV) was found in both groups for doses of 2 micrograms min-1 kg-1 and higher. 3. Metoclopramide infusion did not alter baseline values of GFR, ERPF or FF, but shifted the dopamine dose-response curve for ERPF and FF in the healthy volunteers. Metoclopramide induced a fall in UNa+V and FENa+ in both groups (fall in baseline FENa+ from 1.52 to 0.71 during metoclopramide in healthy volunteers and from 1.23 to 0.56 in patients; P less than 0.01) and blunted the natriuretic response to subsequent dopamine infusion. The fall in UNa+V during metoclopramide infusion showed a strong correlation with baseline GFR (r = -0.944). In the patients, the response for the fractional excretions of beta 2-microglobulin and gamma-glutamyltransferase was comparable with that of FENa+. 4. Dopamine infusion induced a fall, and metoclopramide led to rise, in plasma aldosterone concentration. 5. We conclude that metoclopramide acts as a dopamine antagonist at the renal level in man.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Solitary hamartoma of the lung: is thoracotomy still mandatory?

Solitary pulmonary hamartomas are the most common benign tumors of the lung, and have to be distinguished from primary or secondary malignant pulmonary lesions. The data of 20 patients operated for a solitary hamartoma of the lung are presented with special attention to the diagnostic methods which can contribute to the diagnosis. To avoid a surgical procedure, CT-densitometry and fine-needle aspiration biopsy have become of major interest for the diagnosis of hamartoma. Using in succession chest X-rays, CT-densitometry and fine-needle aspiration biopsy, a conservative approach can be advised in specific cases. However, exploratory thoracotomy is mandatory when a patient presents with a solitary pulmonary lesion of more than 2.5 cm or when the lesion shows a tendency to grow.

Adolescent↗
PubMed1988

Bronchopulmonary carcinoids and regional lymph node metastases. A quantitative pathologic investigation.

Bronchopulmonary carcinoid tumors are tumors with a low malignant potential. They metastasize in 5-15% of cases. Accurate histologic preoperative prediction of the presence of regional lymph node metastases is not possible at this time. A retrospective quantitative pathologic analysis was performed to investigate the possibility of predicting the presence or absence of regional lymph node metastases in 24 patients with bronchopulmonary carcinoid tumors. The results of univariate analysis showed that large tumor size was associated significantly more frequently with regional lymph node metastases than small tumor size (P less than 0.01). The other quantitative features, ie, a larger mean nuclear area, higher standard deviation of the nuclear area and the presence of an aneuploid DNA index, were frequently associated with regional lymph node metastases, but this tendency was not significant. In multivariate analysis the combination of tumor size and mean nuclear area predicted the presence or absence of regional lymph node metastases correctly in 80 and 94% of the cases, respectively. These results indicate that the combination of tumor size and mean nuclear area may serve as a guideline to predict the presence of regional lymph node metastases.

Adult↗
PubMed1987

The protective potential of the combination of verapamil and cimetidine on cisplatin-induced nephrotoxicity in man.

Nine patients (Group A) with histologically proven, nonseminomatous testicular cancer were treated with cisplatin (CDDP) according to the Einhorn regimen. Renal function studies including the measurement of the effective renal plasma flow (ERPF) and the glomerular filtration rate (GFR) were performed prior to the chemotherapy and then after treatment on days 10 and 21 of the first course. In order to prevent CDDP-induced nephrotoxicity, verapamil (a calcium entry blocker) and cimetidine were given along with CDDP. The results were compared with others from another group of nine patients (Group B) treated with CDDP, but without verapamil and cimetidine. In Group A there was much less of a decrease in ERPF as compared to Group B on day 21. In addition, the decrease in GFR on days 10 and 21 was totally prevented in the verapamil- and cimetidine-treated group.

Adult↗
PubMed1987

Continent urostomy: a clinical experience in 20 patients.

Urinary diversion via a continent ileal reservoir (modified Kock's procedure) was performed in 20 patients. Primary continent urostomy construction was carried out in 6 patients. Previous urinary diversion was present in 12 patients. Two patients were referred to us because a previous attempt to construct a continent reservoir urostomy had failed. There was no operative mortality. Three early complications occurred in 3 patients. Leakage from a uretero-enteric anastomosis in one patient and necrosis of a continence-providing valve in another patient necessitated reoperation. Late complications causing malfunction of the nipple valves required revisional surgery in 2 patients. Stoma stricture developed in 1 patient after 5 months and could be corrected surgically. The functional results were excellent. Continence was achieved without reflux to the upper urinary tract. Instead of a Kock pouch, an S-pouch was used. The continence and antireflux-providing valves were stapled to the reservoir wall. Slippage of the nipple valves did not occur. All our patients had consistently positive urine cultures and were without complaints. In a few cases, stone formation was observed usually on the staples at the tip of the valve. The stones were removed by forceps during endoscopy of the reservoir.

Adult↗
PubMed1987

[The treatment of rectal carcinoma in the elderly patient. Is there room for local treatment?].

The treatment of choice for low rectal carcinoma is an abdominal perineal excision of the rectum or an anterior resection. These surgical procedures have a significant morbidity and mortality, especially in elderly patients. An abdominal perineal excision of the rectum requires a permanent colostomy. In elderly and so called high risk patients local treatment is an attractive alternative. For many years local excision electrocoagulation, contact irradiation and cryotherapy have been well known local treatment modalities. Indications for and results of the various methods of local treatment are discussed.

Aged↗
PubMed1987

[Cryotherapy of rectal tumors in the elderly patient].

Until now 29 patients (older than 70 years of age) have been treated by cryotherapy for a rectal carcinoma. In 8 patients the tumour disappeared while in 14 good palliation was achieved. Small tumours of the rectal wall can be treated curatively by cryotherapy. In larger tumours local symptoms can be diminished avoiding a permanent colostomy. Complications due to cryotherapy are rare.

Aged↗
PubMed1987

Pneumatosis intestinalis related to cytomegalo-virus infection--a new etiology?

Five patients who developed pneumatosis intestinalis in the course of a cytomegalo virus (CMV) infection after cadaveric kidney transplantation are described. Based on the fact that CMV is known to cause intestinal ulcers, we postulate a causal relationship between CMV and pneumatosis intestinalis.

Cytomegalovirus Infections↗
PubMed1987

Renal reserve filtration capacity in patients with type 1 (insulin-dependent) diabetes mellitus.

Glomerular hyperfiltration is one of the factors held responsible for the development of diabetic nephropathy. A supranormal glomerular filtration rate (GFR) can be found in diabetic patients even when they are well controlled. Infusion of low-dose dopamine demonstrates that glomerular hyperfiltration in well-controlled insulin-dependent diabetic patients is not based on a predominant vasodilatation of the efferent arteriole. In the present study this is confirmed, since the dopamine-induced rise in GFR of control subjects (13.5% +/- 2.2) did not differ from that of patients with insulin-dependent diabetes mellitus (10.8% +/- 2.1). In animal studies it has been demonstrated that the increased GFR in diabetes mellitus is caused by a predominant decrease in resistance of the afferent arteriole. Protein loading and infusion of amino acids also increase GFR by dilatation of the afferent arteriole. Thus, protein loading or amino acid infusion may be used to test the existence of afferent vasodilatation. The present study investigates the effect of amino acid infusion on GFR of control subjects and insulin-dependent diabetic subjects. The amino acid-induced rise in GFR tended to be lower in the diabetic patients (6.9% +/- 2.8) compared with controls (13.2% +/- 2.7). Percentage amino acid-induced change in GFR appeared to decline with increasing baseline GFR in the diabetic subjects (r = -0.83; P less than 0.001). In controls, no such relationship was established (r = -0.22; n.s.). Our results suggest the existence of afferent vasodilatation in diabetic patients with a high GFR. The cause of this vasodilatation warrants further study.

Adult↗