Biomedical subjects

W C Hop

Publications and source records attributed to W C Hop.

At least 19 recordsLinked to original sources

PubMed1992

Adenocarcinoma of the gastric cardia. Recurrence and survival after resection.

Between January 1, 1983, and December 31, 1988, operations were performed on 112 patients with adenocarcinoma of the gastric cardia. Resection of the primary tumor was performed in 93 patients. For these 93 patients, follow-up until July 1, 1989, averaged 24 months, during which time 59 patients died. Positive resection margins carried a greater risk for the development of a local recurrence but did not correlate with survival. The cumulative overall 5-year actuarial recurrence rate was 69%. The cumulative 5-year recurrence rate for metastases was 64% and for locoregional recurrence it was 36%. The overall 5-year survival rate was 24%. Differences in survival were observed between patients with carcinomas of the various subgroups of the 1987 TNM classification system (T1-T2 versus T3-T4, N0 versus N1-N2, M0 versus M1, Stages I-II versus Stages III-IV, Grades 1-2 versus Grades 3-4). In particular, lymph node status as correlated with histopathologic grade showed remarkable differences in survival: patients with no positive lymph nodes in the resection specimen and a Grade 1 or 2 tumor had a significantly better 5-year survival rate (53%) than the other subgroups (N0/Grades 3-4: 21%; N1-N2/Grades 1-2: 12%; N1-N2/Grades 3-4: 14%).

Adenocarcinoma↗

PubMed1992

Mechanical agitation of very dilute antiserum against IgE has no effect on basophil staining properties.

A previously reported effect of mechanically agitated dilutions of antiserum raised against IgE was investigated using the loss of metachromatic staining properties of human basophil leukocytes as a model. A series of 24 blind experiments was performed in which we determined the number of toluidine blue-stainable basophils after incubating with vortexed or non-vortexed dilutions of anti-IgE. Tenfold serial dilutions were used, in the range 10(21) to 10(30) (6.6 x 10(-26) to 6.6 x 10(-35) M anti-IgE). We found no evidence for a different effect of strongly agitated dilutions, compared to dilutions made with minimal physical agitation. In fact, in our hands no effect of extreme dilutions was shown at all. We conclude that the effect of extreme dilutions of anti-IgE, reported by Davenas et al., needs further clarification and that in this process the reproducibility of results between experimenters should be carefully determined.

Basophils↗

PubMed1992

Measurement of bronchial responsiveness in young children: comparison of transcutaneous oxygen tension and functional residual capacity during induced bronchoconstriction and -dilatation.

Demonstration of an increased bronchial responsiveness in preschool children may support the diagnosis of asthma. Most young children cannot perform routine lung function tests. Transcutaneous PO2 (PtcO2) measurement has been applied successfully in young children, and changes in PtcO2 have been shown to correlate well with changes in forced expiratory volume in 1 second (FEV1) during bronchoprovocation testing with methacholine. PtcO2 is, however, an indirect measure of the effect of inhaled spasmogens. As functional residual capacity (FRC) can also be measured by helium dilution spirometry in preschool children, we compared PtcO2 and FRC during methacholine inhalation challenges and after inhaled terbutaline, in order to determine whether FRC is useful as a more direct measure of induced bronchoconstriction and -dilatation than PtcO2. We studied 41 allergic asthmatic children (mean age, 5.2 years) who underwent a methacholine bronchoprovocation test; 38 children received terbutaline 1 h after the final methacholine dose. The provocative concentration of methacholine that caused a 20% decrease of PtcO2 was determined, and changes in FRC and PtcO2 after each methacholine dose step were compared. Similarly, changes in PtcO2 and FRC before, and 15 and 30 min after, terbutaline were compared. All children had a drop in PtcO2 after increasing doses of methacholine; a 20% change was reached in 38 patients. Mean FRC values increased significantly but variably with increasing doses of methacholine, and changes in PtcO2 and FRC did not correlate. After terbutaline, PtcO2 increased slightly but significantly, and FRC again varied unpredictably. In a separate group of 11 children, the effect of terbutaline was assessed directly after the final methacholine dose, when significant bronchoconstriction was still present.(ABSTRACT TRUNCATED AT 250 WORDS)

Asthma↗

PubMed1992

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↗

PubMed1992

Survival and prognostic indicators in hepatitis B surface antigen-positive cirrhosis of the liver.

To evaluate indications for new therapies such as liver transplantation and antiviral therapy, survival of histologically proven hepatitis B surface antigen (HBsAg)-positive cirrhosis of the liver was assessed in a cohort of 98 patients followed up for a mean of 4.3 years. The overall survival probability was 92% at 1 year, 79% at 3 years, and 71% at 5 years. Variables significantly associated with the duration of survival were age, serum aspartate aminotransferase levels, presence of esophageal varices, and all five components of the Child-Pugh index (bilirubin, albumin, coagulation factors, ascites, encephalopathy). Multivariate analysis showed that only age, bilirubin, and ascites were independently related to survival. Survival of patients with decompensated cirrhosis (determined by the presence of ascites, jaundice, encephalopathy, and/or a history of variceal bleeding) and those with compensated cirrhosis at 5 years was 14% and 84%, respectively. For patients with compensated liver cirrhosis, hepatitis B e antigen (HBeAg) positivity was also a prognostic factor with a 5-year survival of 72% for HBeAg-positive cirrhosis and 97% for HBeAg-negative cirrhosis; the risk of death was decreased by a factor of 2.2 when HBeAg seroconversion occurred during follow-up. It is concluded that liver transplantation should be considered for patients with decompensated HBsAg-positive liver cirrhosis and antiviral therapy for patients with HBeAg-positive compensated cirrhosis.

Adult↗

PubMed1992

Long-term results of transplantations to repair median, ulnar, and radial nerve lesions by a microsurgical interfascicular autogenous cable graft technique.

A comprehensive analysis of 187 patients (78 median, 86 ulnar, and 23 radial nerve lesions) treated by an interfascicular autogenous nerve grafting technique is presented. After a follow-up of at least 18 months good motor recovery was achieved in 72% of median nerve lesions, 77% of ulnar nerve lesions, and 57% of radial nerve lesions. Good functional sensory recovery was found in 36% of median, 45% of ulnar, and 48% of radial nerve lesions. It appears by multivariate analysis that the results obtained generally were better in younger patients, in patients with a shorter preoperative delay, and in cases with a shorter transplant.

Adolescent↗

PubMed1992

Quality of Life in patients with resected oesophageal cancer.

Quality of Life (QL) is hard to assess and seldom measured in patients having carcinomas with an unfavourable prognosis. Oesophageal cancer is one of the malignancies with a low 5-year survival rate. Dysphagia (problems in swallowing food) is considered to be the most important indicator of QL in patients with oesophageal carcinoma. Moreover, the psycho-social aspects and subjective QL in cancer have recently gained importance. The present study investigated QL in a 132 patients with oesophageal cancer. Eighty-three of them had a surgical operation (removal of part of the oesophagus and part of the stomach, followed by a reconstruction of the digestive tract). Sixty-seven patients filled in questionnaires before and after the operation. Complete sets of data were obtained from 62 patients. Time interval between operation and postoperative assessment varied from 3 to 7 months. Indicators of QL were: Psychological Distress, Physical Symptoms, Global Evaluations, Activity Level, Swallowing Problems and Food Intake. Swallowing Problems showed moderate correlations with the other QL indicators. Physical Symptoms increased, whereas the Activity Level, Psychological Distress, and Swallowing Problems decreased; Global Evaluations remained unaltered.

Aged↗

PubMed1992

Pulse pressure assessment in the human fetal descending aorta.

Pulsatile vessel diameter recordings were obtained at two different levels of the fetal descending aorta in ten third-trimester human fetuses using an echo-tracking system. A derivation of the Moens-Korteweg equation was used to estimate the pulse pressure amplitude in this vessel. The positive phase of the first derivative of the diameter curves was cross correlated to assess the propagation time of the pulse wave. It is postulated that this method minimises the measuring errors resulting from diameter pulse wave changes during propagation along the longitudinal axis of the descending aorta. It was estimated from repeated measurements that approximately 13 recordings of 5.2 s each are required to assess the mean pulse pressure amplitude for an individual fetus with an estimated random error of 10%.

Aorta, Thoracic↗

PubMed1992

Reproducibility of fetal cardiac flow velocity waveforms at atrioventricular level.

Reproducibility of flow velocity waveform recording and analysis was studied at fetal atrioventricular level (mitral and tricuspid valve) in 25 normal pregnancies. The flow velocity parameters studied were peak-E wave velocity, peak-A wave velocity and time-averaged velocity. In each patient, two consecutive measurements were performed (time delay, 15 min) and of each measurement two hardcopies were analyzed. A high reproducibility was achieved for all parameters studied; the coefficients of variation between readings of hardcopies were < or = 2% and the coefficients of variation between tests within patients were < or = 4%.

Adult↗

PubMed1992

Growth patterns of ovarian follicles during induction of ovulation with decreasing doses of human menopausal gonadotropin following presumed selection in polycystic ovary syndrome.

Data presented in this study indicate that ovulation can be induced in patients with PCOS using a GnRH analogue combined with hMG in a decreasing dose regimen. Based on the observed decline in functional, medium sized follicles in the late follicular phase, it may be speculated that the risk of ovarian hyperstimulation during gonadotropin induction of ovulation in patients with PCOS can be reduced.

Adult↗

PubMed1992

Prognosis and prostatic volume changes during endocrine management of prostate cancer: a longitudinal study.

A total of 102 patients with histologically proved prostate cancer was followed by transrectal ultrasonography to determine the volume of the prostate during endocrine treatment. The mean volume reduction of the prostate at 3 months after start of treatment was 37.1%, and it was greater in patients treated by orchiectomy (42.1%) compared to those treated by luteinizing hormone-releasing hormone (30.5%). Without consideration of other factors, patients in whom the volume of the prostate had regressed 50% or more at 3 months had a better prognosis (overall survival, intercurrent death corrected survival and survival without distant progression) compared to those with a smaller volume reduction. However, when adjusted for the 2 most important prognostic factors in this study, histological grade and M category, no benefit from a greater prostate reduction as shown by ultrasound could be demonstrated. Similar results applied to the ultrasound findings at month 6. In 24 of the 102 patients an increase of prostatic volume by more than 20% was found after a median interval of 18 months, which was considered local progression. During the observation period systemic progression was encountered in 61 patients. When local progression was observed, the rate of subsequent distant progression was increased by a factor of 2.7, irrespective of grade and M category.

Follow-Up Studies↗

PubMed1992

The advantages of pylorus-preserving pancreatoduodenectomy in malignant disease of the pancreas and periampullary region.

The aim of this study was to establish whether the pylorus-preserving pancreatoduodenectomy (PPPD) is a safe and radical procedure in malignant disease of the head of the pancreas and periampullary region, without increased morbidity and mortality rates compared with the standard Whipple's procedure. During the period 1984 to 1990, a Whipple's procedure (n = 44) or PPPD (n = 47) was performed in 91 patient. In-hospital mortality rates were 2% after PPPD and 5% after Whipple's procedure. Median duration of the resection procedure and median blood loss in the PPPD group were 210 minutes and 1800 mL, respectively. After Whipple's procedure, these figures were 255 minutes and 2500 mL, both significantly different (p less than 0.01) as compared with PPPD. No difference was found during follow-up with respect to days of gastric suctioning, start of liquid diet, normal diet, complaints of ulcer disease, postoperative complications, recurrence of disease, and survival. In all patients, curative resection was performed with comparable TNM (tumor, nodes, metastases) staging. The number of tumor-containing duodenal or gastric resection margins did not differ in both groups of patients (two patients after PPPD, two patients after Whipple's procedure). Hospital stay was significantly (p = 0.02) shorter after PPPD; median 14 days, compared with median 18 days after Whipple's procedure. The advantage of the PPPD is that it is an easier and less time-consuming operation, with less blood loss, a shorter hospital stay, and better weight gain (p = 0.02) during follow-up. In conclusion, PPPD is a safe and radical procedure for cancer in the head of the pancreas or periampullary region, with the same survival and appearance of locoregional recurrence and distant metastases as after standard Whipple's resection.

Ampulla of Vater↗

PubMed1992

17 beta-Oestradiol, androstenedione and inhibin levels in fluid from individual follicles of normal and polycystic ovaries, and in ovaries from androgen treated female to male transsexuals.

OBJECTIVE: The aim was to monitor carefully follicular growth arrest in polycystic ovaries by assay of hormones in individual follicles. DESIGN AND PATIENTS: Fluid from follicles less than or equal to 10 mm was obtained from ovaries of 16 regularly cycling women between days 1 and 12 of the follicular phase (controls, n = 120 follicles), polycystic ovaries of five women with polycystic ovary syndrome (n = 43), and polycystic ovaries from 14 long-term testosterone treated female to male transsexuals (n = 120). MEASUREMENTS: Fluid was assayed for oestradiol, androstenedione, and immunoactive inhibin. Luteinizing hormone, follicle-stimulating hormone, and testosterone levels were estimated in serum. RESULTS: Median serum LH was lower in transsexuals than in controls (P less than 0.05), and in polycystic ovary syndrome (P less than 0.01). Median serum testosterone was not significantly different between polycystic ovary syndrome and transsexuals, and was elevated in both groups as compared to controls (P less than 0.01). Oestradiol was present in all follicles obtained from polycystic ovaries of polycystic and transsexual patients, in which no follicle greater than 10 mm could be detected. In the three groups, between-patient differences in mean oestradiol, androstenedione, inhibin, and androstenedione/oestradiol ratio were significantly larger than expected in view of the variation between follicles within individuals. Taking into account this between-patient difference, no significant differences could be established between the three groups for all endocrine parameters. The percentage of presumed healthy follicles (androstenedione/oestradiol ratio less than or equal to 4) was 12% in controls, 17% in polycystics, and 14% in transsexuals, and was not significantly different between groups. CONCLUSIONS: The results may indicate that (1) abnormally high circulating androgen concentrations with or without elevated LH levels disturb the process of selection, and could therefore play a role in the pathogenesis of polycystic ovaries; (2) in polycystic ovaries from polycystic ovary syndrome and transsexual patients, aromatase activity is present in vivo in small antral follicles, and the proportion of presumed healthy follicles is not different from that encountered in normal ovaries; (3) oestradiol levels are not different between non-dominant follicles of normal and polycystic ovaries, suggesting that only enhancement of aromatase activity by FSH may be disrupted in polycystic ovaries, (4) because androstenedione levels are not different comparing follicles of normal and polycystic ovaries, hyperandrogenaemia in the syndrome seems to originate from the abnormally high number of cystic atretic follicles generally observed in polycystic ovaries; (5) marked variation in the endocrine follicular microenvironment within and between-women precludes pooling fluid from several follicles.

Adult↗

PubMed1992

The significance of a single serum LH measurement in women with cycle disturbances: discrepancies between immunoreactive and bioactive hormone estimates.

OBJECTIVE: We evaluated the significance of single serum LH estimates (as assessed by radiometric assay (IRMA) and Leydig cell in-vitro bioassay (BIO)) for the diagnosis of polycystic ovary syndrome (PCOS) in women with infertility and cycle abnormalities. DESIGN: Hormonal and clinical comparisons between subgroups were made based on classification according to (a) rigid clinical and endocrine (excluding LH) characteristics of PCOS, (b) elevated IRMA-LH concentrations, (c) BIO-LH levels. In addition, androgen modulation of LH biopotency was studied in these patients. PATIENTS: Ninety-nine women presenting at our infertility Unit with oligo/amenorrhoea. MEASUREMENTS AND RESULTS: Of the total study group, 35 women were diagnosed positive as PCOS and 42 showed elevated IRMA-LH levels. Only 51% (n = 18) of PCOS patients showed elevated IRMA-LH levels, and in PCOS significantly higher levels of BIO-LH, androstenedione, oestrone, and BIO/IRMA-LH ratios were found as compared to non-PCOS patients. In the group with elevated IRMA-LH only 43% (n = 18) of subjects were diagnosed as PCOS, and no difference in BIO/IRMA-LH ratios was found. With increasing BIO-LH levels the probability of PCOS rises sharply (P < 0.001), whereas this probability is of only marginal significance (P < 0.06) for IRMA-LH. In the total study group a correlation is observed between serum testosterone (T) levels and IRMA-LH (r = 0.47), and BIO-LH (r = 0.51) concentrations. This correlation is absent comparing serum T and BIO/IRMA-LH ratios (r = 0.15). CONCLUSIONS: Results presented in this study indicate that (1) women with infertility and oligo/amenorrhoea classified based on signs of PCOS or IRMA-LH levels, exhibit different clinical and endocrine characteristics, (2) only 51% of PCOS women exhibit elevated IRMA-LH concentrations, and only 43% of women with elevated IRMA-LH were diagnosed as PCOS, (3) IRMA-LH levels are a poor predictor of PCOS, whereas the predictive value of BIO-LH is better, (4) elevated BIO/IRMA-LH ratios in PCOS are dependent on alterations in BIO-LH, rather than IRMA-LH concentrations, and (5) no correlation was observed between serum T levels and BIO/IRMA-LH ratios.

Adult↗

PubMed1992

Outcome of surgical treatment of adenocarcinoma in Barrett's oesophagus.

A retrospective study was performed of an 11 year period (1978-88) to analyse the survival of 112 patients (85 men and 27 women, mean age 63 years) with adenocarcinoma in a columnar lined (Barrett's) oesophagus in respect of surgical treatment, tumour staging, and histological grading. Presenting symptoms were dysphagia (60%) and pain (25%). Only six patients were previously known to have a columnar lined oesophagus. Eighty five patients (76%) underwent partial resection of the oesophagus and cardia. Postoperative mortality was 6%. After resection (n = 85), the 5 year survival was 24%. Survival was significantly better for patients without regional lymph node metastases (stage 0, I, IIA (n = 61): 5 year survival 30%) and even better if the tumour was restricted to the submucosa (stage 0, I (n = 12): 5 year survival 63%). Survival was not influenced by the histological grade of the tumour. Staging based on infiltration of the oesophageal wall and lymph node spread is valuable in determining the prognosis for patients with adenocarcinoma in Barrett's oesophagus.

Adenocarcinoma↗

PubMed1992

Achalasia complicated by oesophageal squamous cell carcinoma: a prospective study in 195 patients.

To determine the incidence of oesophageal carcinoma in patients with achalasia and to establish the efficacy of endoscopic surveillance, 195 consecutive patients with achalasia (90 men and 105 women, mean age 52 years), who were treated by pneumatic dilatation in our institution between 1973 and 1988 were prospectively studied. None of the patients had undergone cardiomyotomy. Follow up totalled 874 person years after pneumatic dilatation. In this period three patients developed an oesophageal squamous cell carcinoma. The mean age at diagnosis of the oesophageal carcinoma was 68 years (37, 77, and 89 years). The mean period between the onset of dysphagia and the diagnosis of the tumour was 17 years (19, 28, and 5 years); the mean interval between the diagnosis of achalasia and carcinoma was 5.7 years (5, 8, and 4 years). The incidence of oesophageal squamous cell carcinoma in this series (3.4/1000 patients per year) is significantly higher than the statistically expected incidence (0.104/1000 patients per year) using age and sex specific incidence data from the population of the Netherlands (Poisson statistics: p less than 0.001). The risk of developing oesophageal squamous cell carcinoma in patients with achalasia is therefore increased 33 fold. Periodic endoscopy showed the potential for detecting early stage oesophageal carcinoma in two cases but a larger study with a longer follow up is required to determine the efficacy of endoscopic screening in improving the prognosis for patients with achalasia who develop oesophageal squamous cell carcinoma.

Adult↗

PubMed1992

How to discriminate between normal and polycystic ovaries: transvaginal US study.

Transvaginal sonography was used in 29 women with regular menstrual cycles and 52 patients with the polycystic ovary syndrome to determine cutoff levels in the size and number of ovarian follicles and ovarian echogenicity and volume for diagnosis of polycystic ovaries. Median values of the mean size and number of follicles and ovarian volume were, respectively, 5.1 mm, 5.0, and 5.9 mL in control subjects and 3.8 mm, 9.8, and 9.8 mL in patients. Ovarian stroma echogenicity was normal in 26 control subjects (90%) and moderately increased in three control subjects (10%), whereas it was markedly increased in 28 patients (54%), moderately increased in 21 patients (40%), and normal in 13 patients (6%). The sensitivity and specificity of moderately or markedly increased echogenicity of ovarian stroma in the diagnosis of polycystic ovaries was 94% and 90%, respectively. The greatest power of discrimination between normal and polycystic ovaries was obtained with combined measurement of follicular size and ovarian volume (sensitivity, 92% [48 of 52 patients]; specificity, 97% [28 of 29 control subjects]).

Adult↗

PubMed1992

Pelvic phleboliths: is there an association with diverticulitis?

Pelvic phleboliths are familiar structures to radiologists although their pathogenesis is not fully understood. The literature suggests a relationship between the prevalence of phleboliths and diverticular disease, and with a low-fibre diet. Phleboliths are said to be seen more frequently in women and on the left side in the pelvis. Their number seems to increase with advancing age. We have attempted to establish relations of phleboliths with diverticulitis, diverticulosis, sex, age and pelvic location. In this study the only statistically significant relation was an increase of the number of phleboliths with advancing age.

Adult↗