Biomedical subjects

W C Hop

Publications and source records attributed to W C Hop.

At least 217 records · Page 12Linked to original sources

PubMed1994

Quality of palliation and possible benefit of extra-anatomic reconstruction in recurrent dysphagia after resection of carcinoma of the esophagus.

BACKGROUND: After "curative" resection of carcinoma of the esophagus, late secondary dysphagia almost invariably indicates locoregional tumor recurrence. The retrosternal reconstruction route is advocated to prevent ingrowth of tumor recurrence in the neoesophagus. STUDY DESIGN: To evaluate the quality of palliation after "curative" resection of carcinoma of the esophagus and the possible benefit of the retrosternal reconstruction route, we retrospectively analyzed the records of patients who had resection of a malignant tumor of the esophagus, or the gastroesophageal junction, and a prevertebral reconstruction. The extra-anatomic route would have been only beneficial for patients with intrathoracic tumor recurrence distant from the anastomosis and causing gastrointestinal symptoms. RESULTS: Between 1983 and 1989, 209 patients (mean age of 61.3 years at the time of operation) had "curative" resection and prevertebral reconstruction in the institution of this study. Seventy-three patients (35 percent) had locoregional tumor recurrence. Univariate and multivariate analysis of various risk factors for locoregional recurrence showed that the presence of positive lymph nodes (pN1), especially if located at the celiac trunk (pM1), and a macroscopically non-radical R2 resection were the most important risk factors. Forty-six patients (22 percent) had secondary dysphagia as a result of locoregional tumor recurrence, mostly (18 percent) within two years postoperatively. Dysphagia lasted on average 5.3 months (range of 0.3 to 21.5 months) before the patients died. In 27 patients (13 percent), dysphagia would probably have been prevented by using a retrosternal reconstruction route. CONCLUSIONS: These data are an argument in favor of the extra-anatomic, retrosternal reconstruction route after limited transthoracic or transhiatal resection in the presence of positive lymph nodes. This method seems especially indicated if the nodes are located at the celiac trunk and in case of a macroscopically nonradical R2 resection.

Adult↗

PubMed1993

Risk factors for the development of an adenocarcinoma in columnar-lined (Barrett) esophagus. The Rotterdam Esophageal Tumor Study Group.

BACKGROUND: To evaluate the importance of the length of columnar-lined esophagus, sex, age, smoking, and drinking habits as risk factors for malignant degeneration, the authors performed a retrospective case-control study comparing patients with and without adenocarcinoma in Barrett esophagus. METHODS: The records of 96 patients (53 male and 43 female; mean age, 61 years) with a benign columnar-lined esophagus and 62 patients (47 male and 15 female; mean age, 62 years) with an adenocarcinoma in columnar-lined esophagus referred to the Rotterdam Esophageal Tumor Study Group, diagnosed over the same period (1978-1985), were reviewed. A frequency distribution of the length of columnar-lined esophagus in both groups was made. Statistical analysis was performed with multivariate methods. RESULTS: The length of columnar-lined esophagus was related significantly to carcinoma: a doubling of the length resulted in a 1.7 times increased risk. Smokers had a 2.3-fold increased risk as compared with nonsmokers. Male sex as a risk factor approached statistical significance (P = 0.06). Adjusted for these risk factors, no relation between carcinoma and age or alcohol consumption was found. CONCLUSIONS: The risk of development of an adenocarcinoma in Barrett esophagus increased with the length of Barrett epithelium. Smoking and possibly male sex were also risk factors. The identification of these risk factors may help in developing more efficient screening programs for patients with Barrett esophagus.

Adenocarcinoma↗

PubMed1993

Blood transfusions and prognosis in colorectal cancer.

BACKGROUND: Blood transfusions may adversely affect the prognosis of patients treated surgically for cancer, although definite proof of this adverse effect has not been reported. METHODS: We carried out a randomized trial to investigate whether the prognosis in patients with colorectal cancer would be improved by a program of autologous blood transfusion as compared with the current practice of allogeneic transfusion. Patients in the autologous-transfusion group were required to donate two units of blood before surgery. RESULTS: A total of 475 patients were evaluated. We found no significant difference in prognosis between the allogeneic-transfusion group (236 patients) and the autologous-transfusion group (239 patients); colorectal cancer-specific survival rates at four years were 67 percent and 62 percent, respectively (P = 0.39). Among the 423 patients who underwent curative surgery, 66 percent of those in the allogeneic-transfusion group and 63 percent of those in the autologous-transfusion group had no recurrence of colorectal cancer at four years (P = 0.93). We also found that the risk of recurrence was significantly increased in patients who received blood transfusions, either allogeneic or autologous, as compared with patients who did not require transfusions; the relative rates of recurrence were 2.1 (P = 0.01) and 1.8 (P = 0.04), respectively; these rates did not differ significantly from each other. CONCLUSIONS: The use of autologous blood as compared with allogeneic blood for transfusion does not improve the prognosis in patients with colorectal cancer. Regardless of their type, transfusions are associated with poor prognosis, probably because of the circumstances that necessitate them.

Adult↗

PubMed1993

Bronchial responsiveness to inhaled metabisulfite in asthmatic children increases with age.

Inhaled bisulfite (HSO3) aerosol produces bronchoconstriction in asthmatics but not in normals. This effect is probably due to local formation of SO2 which stimulates vagal afferents in the airway mucosa, and gives rise to bronchoconstriction that is partly due to a cholinergic reflex. Metabisulfite (MBS) produces bronchoconstriction in most adult asthmatics, but its effect in children has received little attention. The present study was done to assess MBS-induced bronchoconstriction as a function of age in asthmatic children, and to compare MBS responsiveness with the response to inhaled metacholine (MCH), which is commonly used for bronchoprovocation testing. In 36 children with moderate asthma, selected to cover the age range between 3 and 20 years, we compared airway responsiveness to MBS and MCH, expressed as the provocative dose that causes a 20% fall in baseline forced expiratory volume in 1 sec (FEV1, PD20). We also measured the PD20 to MBS after pretreatment with the anticholinergic ipratropiumbromide, to estimate the noncholinergic component of the response. After bronchial provocation with MCH, a PD20 was reached in 32 children, and no significant relation of PD20 to age was found. A PD20[MBS] was seen in only 17 patients, and more frequently in older children. There was a significant negative correlation between age and PD20[MBS]. Ipratropium pretreatment reduced the response to MBS in 14 of the 17 children who had a PD20[MBS]. The PD20[MBS] after ipratropium pretreatment was also significantly negatively related with age. This suggested that the increased prevalence of MBS responsiveness was due to an increase of the noncholinergic component of the response.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Effect of a single dose of inhaled salmeterol on baseline airway caliber and methacholine-induced airway obstruction in asthmatic children.

BACKGROUND: Salmeterol is a new inhaled selective beta 2-adrenergic receptor agonist with a long duration of action. We studied the duration of the bronchodilation and the protective effect against methacholine-induced airway obstruction of a single dose of salmeterol in a double-blind, randomized, placebo-controlled, crossover design. METHODS: Seventeen boys and three girls with mild-to-moderate asthma participated in the study. On two separate days either 50 micrograms salmeterol or placebo was inhaled. FEV1 and PD20 methacholine were determined before and 1, 4, 8, 12, and 24 hours after inhalation. RESULTS: Salmeterol resulted in a significant bronchodilation compared with placebo, up to 12 hours (p = 0.0001). At 24 hours there was a residual effect that approached significance; mean FEV1 being 8.3% +/- 2.4% above baseline (p = 0.06). Significant protection against airway sensitivity to methacholine after salmeterol inhalation was found at all time points (p < 0.005). Twenty-four hours after administration mean PD20 was still 1.22 +/- 0.29 doubling dose above baseline. No important adverse effects were noted. CONCLUSION: We conclude that a single dose of 50 micrograms salmeterol in children with asthma gives a long-lasting bronchodilation, exceeding 12 hours, which is comparable to the results in adult studies. The duration of the protection against airway sensitivity to methacholine exceeds 24 hours.

Administration, Inhalation↗

PubMed1993

Surgery for intracranial meningiomas in elderly patients.

Ninety-three patients above 60 years of age underwent craniotomy for intracranial meningioma removal between 1980 and 1990 at the University Hospital Rotterdam. Sixty-four patients were 60-70 years of age, 29 were 70 years or older. Retrospectively, operative mortality, morbidity and outcome on discharge from hospital and at 6 months were assessed and correlated with age, sex, size and location of the tumor and preoperative neurological status. Seven patients (7.5%) had no or only minor symptoms, 68 (73%) had moderate neurological symptoms (able to live at home with some assistance) and 18 patients (19.5%) had severe symptoms and were dependent on assistance. Surgical mortality was 14%; after 6 months 17% of patients had died. Postoperative complications (surgical, medical or neurological) occurred in 41%. Neurological status 6 months after surgery was improved in 35 patients (38%), unchanged in 38 patients (41%) and worsened in 20 patients (21%), 16 of whom had died. Outcome on discharge from hospital and after 6 months correlated significantly with preoperative neurological status. There was no significant correlation with age, sex, size or location of the tumor. Removal of intracranial meningiomas in the elderly is associated with a high morbidity and mortality rate. However, a large number of elderly patients benefit from surgery for intracranial meningiomas, especially those patients with a good neurological preoperative status.

Aged↗

PubMed1993

The predictive value of Doppler flow velocity waveforms in the development of abnormal fetal heart rate traces in intrauterine growth retardation: a longitudinal study.

In a longitudinal, blinded study design the predictive value of Doppler velocimetry for the development of an abnormal fetal heart rate trace was assessed in 42 cases of intrauterine growth retardation. Doppler velocity waveform recordings were obtained at 2- to 3-day intervals and characterized by the standard deviation score of the pulsatility index in the umbilical artery and internal carotid artery, and the peak systolic and time-averaged velocity in the ascending aorta and pulmonary artery. Twenty-seven patients did not display an abnormal fetal heart rate trace on the day of entry into the study. During follow-up of these patients, the pulsatility index in the umbilical artery and internal carotid artery were the most predictive parameters for the development of an abnormal fetal heart rate trace. The resulting prognostic index was found to have an acceptable discriminative power in the prediction of abnormal fetal heart rate traces as established in a second group of growth-retarded fetuses.

Blood Flow Velocity↗

PubMed1993

Association between ovarian changes assessed by transvaginal sonography and clinical and endocrine signs of the polycystic ovary syndrome.

OBJECTIVE: To determine whether ovarian polycystic changes estimated by transvaginal sonography correlate with clinical and endocrine findings associated with the polycystic ovarian syndrome. DESIGN: Prospective study. SETTING: Reproductive Endocrinology Unit in the Department of Obstetrics and Gynecology at a teaching hospital. PARTICIPANTS: Ninety-five consecutive patients suffering from oligoamenorrhea entering an infertility treatment program. INTERVENTIONS: All women were examined by transvaginal sonography, assessed for body mass index and hirsutism. Blood withdrawal was performed for hormone estimates. MAIN OUTCOME MEASURES: Ovarian follicle number, volume, and stroma echogenicity. Estimates of immunoreactive and bioactive luteinizing hormone (LH), testosterone (T), free T, insulin levels, and insulin resistance index were performed. RESULTS: Hirsutism was present in 63% of the patients and correlated with the number of follicles, ovarian volume, and stroma echogenicity. Follicle number, ovarian volume, and stroma echogenicity values were significantly correlated with immunoreactive LH, bioactive LH, and T levels. Both T and immunoreactive LH were independently correlated with ovarian structure sonography parameters. Insulin and insulin resistance correlated with ovarian volume and stroma echogenicity. Insulin resistance was of significant additional predictive value of ovarian volume and amount of stroma. Evaluating the predictive value of immunoreactive LH and T together in regard to all sonography parameters, only T levels were statistically significant predictors of increase in follicle number, ovarian volume, and stroma amount. CONCLUSIONS: Although immunoreactive LH and bioactive LH correlated with all ovarian parameters, the effect of androgens on ovarian changes appeared to be independent from LH. This further substantiates the apparent cardinal role of androgens in the genesis of polycystic ovaries. Besides, transvaginal sonography assessment of ovaries is a valuable additional tool for the diagnosis of PCOS. In this regard, insulin resistance is of additional predictive value for ovarian volume and stroma echogenicity.

Adult↗

PubMed1993

The bronchoconstrictor effect of strenuous exercise at low temperatures in normal athletes.

In competitive speed skating healthy athletes complain of subjective variants of exercise-induced bronchoconstriction such as coughing, chest tightness and excessive mucus production. This is especially so after a 1500 m race which can be considered as extremely strenuous. We compared peak expiratory flow (PEF) measurements 3, 10, 20, 60, 90 and 120 min after such a race with baseline, just before the race, in 10 adults in a competitive situation in Calgary (Canada) and The Hague (NL) and in 8 children in Utrecht (NL). A gradual decline in PEF was found, the mean decrease reaching significance (p < 0.05) at 10, 90 and 120 min in Calgary, at 90 and 120 min in The Hague and at 90 min in Utrecht for the children. The mean decrease over the whole period was significantly greater (3.6%, SEM 0.6%) in Calgary when compared with The Hague. The decrease could not be explained by the daily PEF variation that we measured in both groups. We conclude that there is a slight bronchoconstrictory effect, even in healthy athletes, when partaking in this strenuous type of exercise at low temperatures. An explanation may be the strong drying and temperature stimulus to the airways, stimulating vagal nerve activity, causing not only the cough and mucus production but also a gradually increasing minor bronchoconstriction.

Adolescent↗

PubMed1993

Luteal function following ovulation induction in polycystic ovary syndrome patients using exogenous gonadotrophins in combination with a gonadotrophin-releasing hormone agonist.

The luteal phase was studied in 12 polycystic ovary syndrome (PCOS) patients following ovulation induction using exogenous gonadotrophins combined with a gonadotrophin-releasing hormone agonist (GnRH-a). Human menopausal gonadotrophin (HMG) was preceded by 3 weeks of treatment with GnRH-a (buserelin; 1200 micrograms/day intra-nasally) and administered in a step-down dose regimen starting with 225 IU/day i.m. GnRH-a was withheld the day before administration of human chorionic gonadotrophin (HCG; 10,000 IU i.m.). Blood sampling and ultrasound monitoring was performed every 2-3 days until menses. The luteal phase was significantly shorter in PCOS patients as compared to eight regularly cycling controls: 8.8 (3.3-11.4) days [median(range)] versus 12.8 (8.9-15.9) days (P = 0.01). Median peak values for progesterone did not show significant differences comparing both groups: 52.3 (17.1-510.3) nmol/l versus 43.0 (31.2-71.1) nmol/l, respectively (P = 0.8). The interval between the day of the progesterone peak and return to baseline was significantly shorter in the PCOS patients than in controls: 2.5 (0.3-4.9) days versus 4.2 (3.9-10.5) days (P < 0.005). Luteinizing hormone (LH) concentrations during the luteal phase as reflected by area under the curve were significantly lower in PCOS as compared to controls: 4.4 (1.6-21.0) IU/l x days and 49.0 (27.8-79.6) IU/l x days, respectively (P < 0.001). In conclusion, patients with PCOS may suffer from insufficient luteal phases after ovulation induction using HMG/HCG in combination with a GnRH-a. The corpus luteum apparently lacks the support of endogenous LH and may be stimulated only by the pre-ovulatory injection of HCG.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Implicit memory during balanced anaesthesia. Lack of evidence.

The effect of the number of presentations on implicit memory for words was studied in anaesthetised patients. During standardised, balanced anaesthesia, 81 surgical patients were presented with less common specimens of familiar word categories. For each of three word categories the number of word presentations varied between the patients (0 (control), 5, or 30 presentations). Postoperatively, repetition priming was tested by asking patients to generate exemplars for each of the word categories. No implicit memory for the words presented during anaesthesia was found and consequently no effect of number of word presentations could be demonstrated. It is suggested that this finding, which contradicts previous results, may be caused by the relatively low familiarity of the words used.

Adult↗

PubMed1993

Increased specificity of antibody detection in surgical patients with invasive candidiasis with cytoplasmic antigens depleted of mannan residues.

In this study, it was shown that the diagnostic accuracy of antibody detection by a counterimmunoelectrophoresis technique could be improved by using cytoplasmic antigens depleted of mannan residues. The specificity of the counterimmunoelectrophoresis increased from 28.6 to 78.6% when cytoplasmic antigens depleted of mannan were used, while the sensitivity slightly decreased from 80 to 70%.

Antibodies, Fungal↗

PubMed1993

Protein restriction in chronic renal failure.

The aim of the study was to investigate the effect of a protein restricted diet on renal function and growth of children with chronic renal failure. In a multicentre prospective study 56 children (aged 2-18 years) with chronic renal failure were randomly assigned to the protein restricted (0.8-1.1 g/kg/day) or the control group. All children were followed up by the same paediatrician and dietitian. After a follow up period of three years there was no significant difference in glomerular filtration rate between children on a protein restricted diet and children of the control group. There was no significant difference in weight with respect to height and height SD score between the protein restricted and the control group. Compliance with the protein restricted diet, as indicated by the prospective diet diaries and the serum urea:creatinine ratio, was good. This study shows that children with chronic renal failure do not benefit from a protein restricted diet.

Adolescent↗

PubMed1993

Oesophageal varices: how reliable is a barium swallow?

Although barium swallow is a quick and easy method for diagnosing oesophageal varices, there is considerable variation between observers because objective quantitative radiological criteria have so far not been defined. In order to define these criteria, a blind radiological/endoscopic comparative study using endoscopy as the gold standard was retrospectively carried out in 72 patients. A prospective study was then carried out in 47 patients to define the validity of the radiological criteria found by the first study. The results of both studies showed that the length and the width of the mucosal folds representing varices as measured on barium swallow radiographs have a significant relationship with the grade of the varices as determined by endoscopy. We conclude that barium swallow is a quick and reliable method for quantitative assessment of oesophageal varices.

Barium Sulfate↗

PubMed1993

Growth of the dominant follicle is similar to normal in patients with gonadotrophin-stimulated polycystic ovary syndrome exhibiting monofollicular development during a decremental dose regimen.

The aim of this study was to investigate the late follicular phase of seven gonadotrophin-treated patients with polycystic ovary syndrome (PCOS) exhibiting monofollicular growth and to compare developmental characteristics with the dominant follicle in seven regularly cycling control women. Daily serum follicle-stimulating hormone (FSH) levels in patients with PCOS decreased more rapidly compared to controls (-0.3 +/- 0.2 IU/day in controls versus -0.7 +/- 0.4 IU/day in PCOS; p < 0.02). No statistically significant differences were seen in daily increase (30% in controls and PCOS) and mean peak levels (825 +/- 94 pmol/l in controls versus 937 +/- 231 pmol/l in PCOS) of oestradiol (E2) serum levels when comparing both groups. Mean daily growth of the dominant follicle (1.7 +/- 0.4 mm in controls versus 1.9 +/- 0.6 mm in PCOS) was not significantly different. It is concluded from the present study that in patients with PCOS treated with gonadotrophin plus adjuvant gonadotrophin-releasing hormone agonist, development of a single follicle can occur using a decreasing dose regimen resulting in decreasing serum FSH levels. In addition, growth and oestrogen production by the dominant follicle in PCOS is not significantly different from follicle growth under normal conditions.

Adult↗

PubMed1993

Scoliosis in children after thoracotomy for aortic coarctation.

A follow-up study was performed to assess the prevalence of scoliosis in 160 patients in whom aortic coarctation had been treated operatively through a left posterolateral incision in the fourth intercostal space. Scoliosis had not been seen in any patient before the thoracotomy, but a scoliosis of 10 degrees or more was observed in thirty-five patients (22 per cent) at the follow-up examination, which was performed an average of seven years after the thoracotomy. The scoliosis was a thoracic curve and was directed to the left in twenty-six of the thirty-five patients. Most of the curves were mild (between 10 and 20 degrees) and hardly progressed during the follow-up period. The high-risk period for the onset of scoliosis began about three years after the operation. The prevalence of scoliosis did not correlate significantly with the age or sex of the patients.

Adolescent↗

PubMed1993

Prognostic impact of blood transfusions on disease-free survival in colorectal carcinoma.

Blood transfusions have been indicated as having an adverse effect on the prognosis of patients treated surgically for cancer. We carried out a randomized trial to investigate whether a predeposit autologous blood transfusion program improved prognosis in patients with colorectal cancer as compared to the current practice of allogeneic transfusion. This appeared not to be the case. However, the subgroup of untransfused patients had a significantly better disease-free survival compared with transfused patients; 73% and 59%, respectively (p = 0.001). We found that the risk of recurrence was significantly increased for patients transfused with allogeneic, or with autologous, or with both types of blood, compared with those patients who did not require transfusions; relative recurrence rates were 2.3 (p = 0.001), 1.8 (p = 0.044) and 2.5 (p = 0.009), respectively; these three rates did not differ significantly from each other. We conclude that it is not the blood transfusions themselves, but the circumstances that necessitate the transfusions that are the real determinants of prognosis.

Aged↗

PubMed1993

Cardiolipin antibodies and lupus anticoagulant in young patients with a cerebrovascular accident in the past.

To determine whether young patients who suffered a stroke in the past, have a higher prevalence of ACA of LAC as compared to healthy controls, we evaluated 44 stroke patients and 46 controls in a case-control study for the presence of ACA and LAC. All the patients had had a stroke under the age of 50 yr and the stroke date was less than 5 yr ago (mean 2.5 yr). Stroke was defined as an ischaemic cerebral infarction and was confirmed by angiography, CT-scan or MRI. An age- and sex-matched group of healthy volunteers served as controls. The mean age of the patients was 41.4 yr (range 22-52 yr), and of the controls 36.8 yr (range 24-50 yr). Serum and plasma from both groups was examined for IgM- and IgG-ACA and LAC. One patient was positive for both IgG- and IgM-ACA, whereas 3 controls were found positive for IgG-ACA. For 2 patients and 5 controls an equivocal result was obtained for IgG-ACA or IgM-ACA. None of the patients or controls were positive for LAC. The differences between the patient and control group were statistically not significant. In conclusion, no difference was found in the prevalence of cardiolipin antibodies in sera from patients with a stroke within the last 5 yr and an age- and sex-matched control group. There was no correlation either between the presence of lupus anticoagulant and the occurrence of a stroke in the past.

Adult↗