Biomedical subjects
Publications and source records attributed to W C Hop.
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We studied amino acid concentrations in granulocytes and plasma of 24 children with chronic renal failure and 15 healthy children. Granulocytes were isolated from 10 ml of blood using a dextran-Ficoll-Hypaque procedure. Intracellular levels of leucine, isoleucine, methionine, phenylalanine, lysine, histidine, tyrosine, and arginine were significantly lower in children with chronic renal failure than healthy children. There were no significant differences in intracellular and plasma amino acid concentrations between children with chronic renal failure on a well-balanced protein-restricted diet and children with chronic renal failure with a normal protein intake.
OBJECTIVE: The objective of this clinical study was to define the diagnostic value of plain radiography, digital subtraction arthrography and two-phase bone scintigraphy in patients with clinically loose or infected hip prostheses. DESIGN: Digital subtraction arthrograms, scintigrams and plain radiographs of 70 consecutive patients who underwent revision hip arthroplasty were scored individually and in masked fashion for the presence or absence of features indicating loosening of femoral and/or acetabular components. The operative findings acted as the gold standard. RESULTS: Digital subtraction arthrography was best (P < 0.001) for predicting a loose acetabular component, while no significant additional predictive value was found for plain radiographs (P = 0.24) and scintigraphy (P = 0.27). Digital subtraction arthrography was also the most important modality for predicting a loose femoral component (P = 0.001), while the plain radiograph was of significant (P = 0.04) additional value and scintigraphy was of no additional value (P = 0.13) on multivariate analysis. CONCLUSION: Digital subtraction arthrography gives the best results in the prediction of loosening of acetabular and femoral components. Plain radiographs give additional information on loosening of the femoral component, but scintigraphy offers no additional advantage.
There are doubts as to whether rectocele repair (RR) is beneficial for patients with concomitant anismus. The aim of this prospective study was to evaluate the effect of anismus on the clinical outcome of RR. In 71 out of 75 patients who underwent RR evacuation proctography (EP) was performed. Electromyography (EMG) of the pelvic floor and balloon expulsion test (BET) were carried out in 61 and 35 patients respectively. On EP, measuring the central anorectal angle (CARA) and the posterior anorectal angle (PARA), signs of anismus were found in 34 and 28 percent of the patients respectively. EMG and BET revealed anismus in 39 and 71 percent of the patients respectively. These results showed poor agreement. RR was successful in 53 (71%) out of 75 patients (follow up 14-74 months). No differences were found in clinical outcome in patients with and without signs of anismus. In conclusion, RR is beneficial for patients with obstructed defecation, and signs of anismus do not appear to be a contraindication for RR.
We have repeated a study of the objective (labium minus temperature) and subjective (semantic scales) changes in sexual arousability over the menstrual cycle to erotic video stimulation in 20 women with natural cycles. We extended the study with concomitant vibrotactile stimulation of the clitoral region. In an earlier study women tested for the first time in their follicular phase were sexually more aroused (as indicated by greater increase in labium minus temperature) than women tested for the first time during their luteal phase. When these women were retested in their alternative phase of the menstrual cycle, those who were then follicular did not score higher than those who were then luteal. We then postulated the involvement of a cognitive or conditioned phenomenon which was responsible for the women's repeating their initial phase-dependent response when tested the second time in their alternative phase of the cycle. Identical results were obtained in the present study as far as sexual arousability is concerned during the first test, i.e. follicular women generally scored higher than luteal women; this difference in response persisted during the second test. Concomitant vibrotactile stimulation had no effect on labium minus temperature change but raised subjective sexual arousal and caused a 'more pleasurable' response to the erotic video. Subjective sexual and subjective genital arousal were positively correlated, but neither was significantly correlated with labium minus temperature change. The relationship between menstrual cycle phase and sexual arousal was further substantiated by the reported greater increase in sexual desire after the first erotic video in follicular women than in luteal women. This increased desire, as well as more erotic fantasies, persisted during the next 24 h. In conclusion, studies into effects of menstrual cycle phase on sexual arousability in the laboratory should seriously consider the possible learning and conditioning effects as suggested by the present investigation.
We studied the effect of parental educational level (PEL), an indicator of socio-economic status (SES), on survival of children with acute lymphoblastic (ALL) and non-lymphoblastic leukaemia (ANLL). All children with ALL and ANLL diagnosed in The Netherlands in the period 1973-1979, registered by the Dutch Childhood Leukaemia Study Group and followed until 1991 were included. Bone marrow and blood smears had been uniformly classified in a central laboratory; cases with acute lymphoblastic leukaemia (ALL) were subdivided into standard risk (SR) and high risk (HR). PEL, assessed as a risk indicator in a separately conducted population-based case-control study of the same children (response rate: 88%), was divided into low, when neither of the parents had more than elementary school or lower vocational education, and high when either had more. Children with SR ALL of high PEL parents had a slightly higher 10-year survival rate than of low PEL parents (58% versus 54%, P = 0.25), whereas survival for the latter increased more (P = 0.06) from a lower level in the period 1973-1975. However, children of low PEL parents with HR ALL and ANLL had a higher 10-year survival rate compared with children of high PEL parents (P = 0.10 and 0.22, respectively). Children without information on PEL, non-responders, migrants and with missing values exhibited slightly worse survival rates. The influence of PEL on survival of acute leukaemia in children in The Netherlands during 1973-1979 appeared small or even equivocal. Small differences in SES and optimal geographic and financial access to care, delivered through national treatment protocols, may be responsible for these results.
UNLABELLED: Benign stricture formation at the cervical anastomosis after transhiatal esophagectomy with gastric tube interposition is an important source of morbidity. In a large group of patients (n = 269) who had undergone transhiatal esophagectomy with gastric tube interposition, we examined surgical and nonsurgical risk factors for the development of benign strictures at the cervical anastomosis. In addition, we evaluated the results of endoscopic bougie dilation in patients in whom an anastomotic stricture developed. RESULTS: During follow-up, 114 patients (42%) had a benign anastomotic stricture. Only a history of cardiac disease (P = 0.03), postoperative leakage at the anastomosis (p = 0.002), and a stapled rather than a hand-sewn anastomosis (p = 0.04) were found to be independent risk factors for the development of a stricture. In 27 of 60 patients with anastomotic leakage, contrast swallow examination demonstrated only a leak at the anastomosis. Endoscopic bougie dilation of anastomotic strictures was successful in 78% of patients after a median of three dilation sessions (range 1 to 28). In 3% of patients dilations were still being performed, and 19% of patients had died before normal swallowing had been achieved. In two of 519 (0.4%) dilation sessions a major complication occurred. CONCLUSIONS: (1) Patients with preoperative cardiac disease are at an increased risk for anastomotic stricture. (2) Even in patients having no symptoms, a contrast swallow can detect anastomotic leakage that results in an increased risk for the development of anastomotic strictures. (3) The benefit of the stapler device for anastomosis remains to be determined. (4) Endoscopic bougie dilation with the patient mildly sedated is a safe and effective method for the treatment of anastomotic strictures.
BACKGROUND: Inhalation of a single dose of the long-acting beta 2-adrenoceptor agonist salmeterol protects against methacholine-induced airway obstruction and other bronchoconstricting stimuli for at least 12 hours. Hypothetically, twice daily dosing of salmeterol may result in continuous protection. OBJECTIVE: This study was designed to investigate the protective effect of a single dose of salmeterol and of continuous twice daily treatment on airway responsiveness to methacholine. METHODS: In a double- blind, parallel study, salmeterol 50 micrograms twice daily was compared with salbutamol 200 micrograms twice daily. Thirty children with mild asthma, who had little or no bronchial obstruction and were hyperresponsive to methacholine (PD20 < or = 150 micro g) were allocated to receive either salmeterol or salbutamol. Airway responsiveness was measured before study entry, 12 hours after a single dose of drug was given, and monthly during 4 months of daily treatment. Measurements were always performed at the same time of the day, 12 hours after the last dose of medication was administered. RESULTS: No significant differences in FEV 1 were found between treatments at any time point. PD20 significantly increased after the first dose of salmeterol was given (geometric mean, 100 micro g). Geometric mean PD20 values were significantly better during salmeterol treatment than during salbutamol treatment, 52 and 25 micro g, respectively (p = 0.005). CONCLUSION: The protection provided by salmeterol during maintenance treatment was less than that provided after the first dose (p <0.001). However, protection did not diminish during the 4-month treatment period and remained significant compared with baseline (p = 0.003).
Proinflammatory cytokines (tumor necrosis factor [TNF]-alpha and interleukin [IL]-6 and -8), counterinflammatory compounds (IL-10 and soluble TNF receptors p55 and p75 [sTNFR-55 and -75]), and hemostatic parameters were determined in 38 patients with meningococcal septic shock. Eleven patients (29%) died. Serum levels of pro- and counterinflammatory compounds and plasma levels of plasminogen activator inhibitor (PAI)-1 were significantly higher in nonsurvivors. The interval between appearance of petechiae and blood sampling was shorter in nonsurvivors than in survivors (3.6 +/- 2.4 vs. 6.1 +/- 3.3 h; P = 0.4). This interval correlated strongly with the levels of TNF-alpha, IL-6, -8, and -10, sTNFR-55 and -75, and PAI-1. However, with the exception of PAI-1, differences between concentrations of these mediators disappeared after adjustment for the interval. PAI-1 levels correlated with TNF-alpha concentrations (r = .75; P < .001) and were 1.9 (P = .01) times higher in nonsurvivors at a similar TNF-alpha concentration. Thus, an increased PAI-1 response to TNF-alpha may be associated with fatality, probably because of polymorphism of the PAI-1 gene.
To investigate the role of nitric oxide (NO) in bacterial meningitis, concentrations in serum, cerebrospinal fluid (CSF), or both of the precursor (L-arginine) and degradation products of NO (nitrate, nitrite) and tumor necrosis factor (TNF)-alpha were measured in 35 patients and 30 controls. CSF nitrate levels were significantly elevated, mainly due to increased blood-brain barrier permeability, and are therefore not a good parameter for gauging endogenous NO production in the CSF compartment. CSF NO/nitrite levels were significantly elevated in patients. NO/nitrite levels decreased over time (26%/6 h; P < .001). CSF levels of NO/nitrite correlated with those of TNF-alpha (r = .55; P = .001) and glucose (r = -.43; P = .02). CSF levels of L-arginine were lower in patients than in controls (P < .001). Dexamethasone did not exert a significant effect on NO metabolism. In conclusion, enhanced NO production may contribute to anaerobic glycolysis and neurologic damage in bacterial meningitis.
In a prospective study, the effect of dietary sodium restriction on plasma and follicular fluid renin and prorenin concentrations and on fertilization measures was investigated during ovarian stimulation. In all, 18 women undergoing ovarian stimulation for in-vitro fertilization and embryo transfer were randomly divided into groups with and without sodium restriction. Plasma renin and prorenin concentrations were higher in the low sodium than in the normal sodium group. Plasma renin concentrations showed a mid-luteal rise. Plasma prorenin concentrations increased 4-fold on the day of oocyte retrieval, followed by a gradual decline to basal values. The low sodium group had more follicles than the normal sodium group. Neither follicular fluid renin and prorenin concentrations, nor the total amount of follicular fluid renin and prorenin per ovary differed significantly between the two groups. Oocyte yield and fertilization rates were similar in both groups. These rates were correlated with neither renin nor prorenin concentrations in follicular fluid. We conclude that sodium restriction did not influence cyclic plasma variation of renin or prorenin or follicular fluid renin and prorenin concentrations. In addition, fertilization rates were not affected by sodium restriction.
OBJECTIVE: The authors determined the prevalence of foreign body granulomas in intra-abdominal adhesions in patients with a history of abdominal surgery. PATIENTS AND METHODS: In a cross-sectional, multicenter, multinational study, adult patients with a history of one or more previous abdominal operations and scheduled for laparotomy between 1991 and 1993 were examined during surgery. Patients in whom adhesions were present were selected for study. Quantity, distribution, and quality of adhesions were scored, and adhesion samples were taken for histologic examination. RESULTS: In 448 studied patients, the adhesions were most frequently attached to the omentum (68%) and the small bowel (67%). The amount of adhesions was significantly smaller in patients with a history of only one minor operation or one major operation, compared with those with multiple laparotomies (p < 0.001). Significantly more adhesions were found in patients with a history of adhesions at previous laparotomy (p < 0.001), with presence of abdominal abscess, hematoma, and intestinal leakage as complications after former surgery (p = 0.01, p = 0.002, and p < 0.001, respectively), and with a history of an unoperated inflammatory process (p = 0.04). Granulomas were found in 26% of all patients. Suture granulomas were found in 25% of the patients. Starch granulomas were present in 5% of the operated patients whose surgeons wore starch-containing gloves. When suture granulomas were present, the median interval between the present and the most recent previous laparotomy was 13 months. When suture granulomas were absent, this interval was significantly longer--i.e., 30 months (p = 0.002). The percentage of patients with suture granulomas decreased gradually from 37% if the previous laparotomy had occurred up to 6 months before the present operation, to 18% if the previous laparotomy had occurred more than 2 years ago (p < 0.001). CONCLUSIONS: The number of adhesions found at laparotomy was significantly larger in patients with a history of multiple laparotomies, unoperated intra-abdominal inflammatory disease, and previous postoperative intra-abdominal complications, and when adhesions were already present at previous laparotomy. In recent adhesions, suture granulomas occurred in a large percentage. This suggests that the intra-abdominal presence of foreign material is an important cause of adhesion formation. Therefore intra-abdominal contamination with foreign material should be minimized.
BACKGROUND: Barrett's oesophagus carries a 30-fold to 40-fold increased risk of oesophageal cancer. It is unknown whether endoscopic surveillance programmes reduce mortality from oesophageal cancer. METHODS: A cohort study was undertaken of all 166 patients in whom the diagnosis Barrett's oesophagus had been established between 1973 and 1986. RESULTS: One hundred and fifty five of 166 patients could be traced (93%). During a mean follow up of 9.3 years (amounting to 1440 patient years) eight patients had developed oesophageal cancer at random intervals (one case in 180 patient years). All but one of the tumours were diagnosed at endoscopy for symptoms, three in the stage of carcinoma in situ. Risk factors for the development of oesophageal cancer were extensive Barrett's oesophagus exceeding 10 cm (p = 0.02) and Barrett's ulcer at the time of intake (p = 0.009). Seventy six patients were alive; three had undergone surgery for oesophageal cancer and were without recurrence respectively, 12.8 years, 12.1 years, and 7 months postoperatively. Seventy nine patients had died; five of them had developed oesophageal cancer, but in only two cases this had been the cause of death (2.5%). CONCLUSIONS: Oesophageal cancer is an uncommon cause of death in patients with Barrett's oesophagus. The patients of this cohort would not have benefited from an endoscopic surveillance programme.
PURPOSE: To assess agreement between endoanal sonography, endoanal magnetic resonance (MR) imaging, and surgery in depiction and classification of fistula in ano. MATERIALS AND METHODS: Twenty-eight consecutive patients with nonspecific, cryptoglandular fistula in ano were studied. The fistulas were classified with endoanal sonography, endoanal MR imaging, and surgery. Agreement between the modalities was also evaluated. RESULTS: Classification of fistulas was possible in 17 of 28 patients (61%) with sonography, in 25 of 28 (89%) with MR imaging, and in 26 of 28 (93%) with surgery. Concordance between endoanal sonography and MR imaging occurred in 46% of the cases (kappa = 0.27, poor agreement); between sonography and surgery in 36% (kappa = 0.09, no agreement); and between MR imaging and surgery in 64% (kappa = 0.43, moderate agreement). CONCLUSION: Endoanal MR imaging more accurately allows depiction and classification of fistula in ano than endoanal sonography.
In a population-based study of 198 patients with probable early-onset Alzheimer's disease (AD), we studied the occurrence of extrapyramidal signs (tremors and rigidity), myoclonus, psychosis and seizures, as well as their predictive value for mortality. The presence of tremors was significantly associated with the presence of rigidity. The occurrence of myoclonus was significantly associated with the occurrence of seizures. Psychosis and seizures in AD patients were not associated with mortality. The occurrence of extrapyramidal signs and myoclonus at any point in time during the course of AD increased the risk of mortality significantly. When evaluating their relative importance, extrapyramidal signs appeared to be the most important predictor of mortality.
Maximal expiratory flow in chronic obstructive pulmonary disease (COPD) could be reduced by three different mechanisms; loss of lung elastic recoil, decreased airway conductance upstream of flow-limiting segments; and increased collapsibility of airways. We hypothesized that decreased upstream conductance would be related to inflammation and thickening of the airway walls, increased collapsibility would be related to decreased airway cartilage volume, and decreased collapsibility to inflammation and thickening of the airway walls. Lung tissue was obtained from 72 patients with different degrees of COPD, who were operated upon for a solitary peripheral lung lesion. Maximal flow-static recoil (MFSR) plots to estimate upstream resistance and airway collapsibility were derived in 59 patients from preoperatively measured maximal expiratory flow-volume and pressure-volume curves. In 341 transversely cut airway sections, airway size, airway wall dimensions and inflammatory changes were measured. Airflow obstruction correlated with lung elastic recoil and the MFSR estimate of airway conductance but not to airway collapsibility or to the amount of airway cartilage. The upstream conductance decreased as the inner wall became thicker. Airway collapsibility did not correlate with the amount of airway cartilage, inflammation, or airway wall thickness. We conclude that the maximal flow-static recoil model does not adequately reflect the collapsibility of the flow-limiting segment.
We studied the influence of age on mortality and severity of clotting abnormalities in 79 children (median age: 3.1 years) with meningococcal sepsis. Parameters of coagulation and fibrinolysis and plasma levels of cytokines were prospectively measured on admission. The mortality rate was 27%. The age of survivors was significantly different from that of non-survivors (p = 0.013). With the exception of FVII, vWF and t-PA, parameters of coagulation and fibrinolysis, as well as plasma cytokine levels were related to outcome. Patients were divided in two groups: younger and older than median age. The mortality in children < or = 3.1 years was 40% versus 13% in children > 3.1 years (p = 0.006). In contrast to cytokine levels, which were not different between the two age groups, fibrinogen, prothrombin, factors V, VII, VIII, vWF, protein C, antithrombin, FDP, and the ratio PA1-1/t-PA were related to age, indicating a more severe coagulopathy in children < or = 3.1 years despite a similar degree of inflammatory response. A relative deficiency of coagulation factors due to an immature state of the clotting system, as well as an inadequate fibrinolytic response, both related to age may have caused this more severe coagulative response in younger children, and may have contributed to the higher mortality rate.
To establish the number of patients with erectile dysfunction (ED) who appear to be sexually potent when exposed to visual erotic (VES) and vibrotactile stimulation (VIB) and to investigate whether or not older patients are less responsive to VES/VIB than young patients. Retrospective analysis of data on 406 consecutive patients screened for ED with VES, VES + VIB, VES + Intracavernous injection (ICI). Partial or full erection was obtained in 34% of patients with VES, 52% with VES + VIB, 82% with VES + ICI. Men < 40 y (n = 86) responded better than men > 40; between 40 and 80 no differences in penile responses were found. 50% of patients who reported no morning/night erections appeared to have good, rigid nocturnal penile tumescence (NPT). The use of VES, VES + VIB, VES + ICI is strongly recommended in the screening of men with ED of all ages; up to 80% will respond with a good erection. Only a positive penile response has diagnostic significance. The positive results reduce the necessity for further invasive investigations.