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Biomedical subjects

J H Wilson

Publications and source records attributed to J H Wilson.

At least 127 records · Page 7Linked to original sources

Assessment of response of esophageal carcinoma to induction chemotherapy.

Endoscopic ultrasonography (EUS) is currently considered the best available technique for the local staging of esophageal cancer. In a prospective study 11 patients with esophageal squamous cell carcinoma were investigated to evaluate the usefulness of EUS in the assessment of response to induction chemotherapy. Response to chemotherapy was evaluated by means of history of dysphagia, endoscopy, computed tomography (CT) and EUS to assess relief of clinical symptoms, reduction of tumor bulk and depth of tumor invasion (T-stage). One patient was excluded because EUS failed. Tumor response was best correlated with relief of dysphagia and by tumor bulk reduction as determined on endoscopy and CT. We found it not useful to measure reduction of tumor bulk with EUS because of tumor compression by the instrument, stenosis, or the hypoechoic thickening of the esophageal wall caused by an inflammatory reaction after chemotherapy. There was no change in EUS T-staging after induction chemotherapy compared to prechemotherapy assessment. EUS T-staging after induction chemotherapy was accurate in 6 of 10 patients compared to the histopathologic examination of the resected specimen. There was EUS T3-overstaging in 4 patients, caused by partial or complete replacement of the tumor by an inflammatory reaction due to chemotherapy. We conclude that inflammatory changes induced by chemotherapy lead to EUS overstaging of the T stage thus making it a less reliable tool in restaging after chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗

Amiodarone interaction with lidocaine.

We report a case of lidocaine toxicity with seizures that appears to represent a drug interaction with amiodarone. A toxic lidocaine level and reduced lidocaine clearance were documented 65 h after amiodarone was added to the treatment regimen. This is the first report of increased levels and serious clinical toxicity of lidocaine due to amiodarone. The mechanism appears to be altered hepatic metabolism of lidocaine caused by amiodarone.

Aged↗

A population based case-cohort study of drug-induced anaphylaxis.

1. In order to determine the risk of anaphylaxis as an adverse reaction to drugs, a case-cohort study was performed. Cases consisted of all admissions in 1987 and 1988 to all Dutch hospitals with anaphylaxis as the principal diagnosis, and a random sample of admissions with related symptoms. Hospital discharge summaries were classified according to probability to anaphylaxis by a blinded Audit Committee. Of admissions classified as probable or possible anaphylaxis, the causative agent was assessed. The reference cohort consisted of all persons in the catchment area of a sample of pharmacies in The Netherlands, in the period between January 1, 1987 and December 31, 1988. 2. Out of 934 admissions, discharge summaries on 811 admissions were received, of which 727 contained enough clinical details. Out of 727, 391 were classified as probable or possible anaphylaxis. In 336 of these 391, anaphylaxis was reason for admission. This group consisted of 158 men and 178 women. Drug-induced anaphylaxis occurred in 107 patients. 3. Drug-induced anaphylaxis was most frequently caused by penicillins, analgesics and non-steroidal antiinflammatory drugs (NSAID) with the highest point estimate of the risk relative to all other drugs of 10.7, 6.9 and 3.7 respectively. 4. In the cases of probable anaphylaxis, the risk of anaphylaxis to glafenine relative to all other drugs was 167.7 in 1987 (95%-CI: 63.0-446.4) and 128.6 in 1988 (95%-CI: 50.4-328.5), to amoxycillin 15.2 in 1987 (95%-CI: 5.0-46.0) and 4.4 in 1988 (95%-CI: 1.03-18.9) and to diclofenac 6.1 in 1988 (95%-CI: 1.4-26.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Paracentesis. The importance of optimal ascitic fluid analysis.

An accumulation of peritoneal fluid can result from a variety of conditions, cirrhosis of the liver being responsible for about 75% of all patients with ascites. Malignancy accounts for 10-12% and cardiac failure for about 5%. The remaining 8-10% of ascites cases have a variety of causes, including tuberculosis, pancreatic disease and kidney disease. An early and accurate diagnosis often depends on an appropriate ascitic fluid analysis. Patients with known liver cirrhosis and clinical deterioration also need to have a paracentesis, with a determination of the ascitic fluid leukocyte and neutrophil count and adequate bacteriological cultures of their ascitic fluid. The diagnostic value of different ascitic fluid parameters and their ability to distinguish between several aetiologies and their complications, is discussed.

Ascites↗

Characterization of a new mutation (R292G) and a deletion at the human uroporphyrinogen decarboxylase locus in two patients with hepatoerythropoietic porphyria.

A deficiency in the activity of uroporphyrinogen decarboxylase (UROD), the fifth enzyme of the haem biosynthetic pathway, is found in familial porphyria cutanea tarda (F-PCT) and hepatoerythropoietic porphyria (HEP). A new mutation (R292G) and a deletion have been found in a pedigree with two HEP patients (two sisters). The R292G mutation was not detected in 13 unrelated affected patients with F-PCT, so it appears to be uncommon. The possibility that the arginine 292 may participate at the active site of the enzyme is discussed. A summary of the 7 mutations/deletions found in the UROD gene with their frequency is presented.

Amino Acid Sequence↗

Forecasting hospital laboratory procedures.

Improved forecasts of hospital laboratory procedures can provide the basis for better resource planning and enhanced operating efficiency. The research reported here-in describes how multiple regression models can be both a source of insight into causal relationships and a tool for achieving accurate monthly forecasts. Past research in this area may have overstated the statistical significance of findings because of a failure to address the potential effect of serial correlation. The present study uses the Cochrane-Orcutt regression procedure, rather than OLS, to overcome this problem. A model using inpatient admissions, acuity days, length of stay, discharge days and seasonal dummy variables is shown to account for 87% of the variation in the number of billable laboratory procedures. A simpler multiple regression model and a Winters' exponential smoothing model were found to provide excellent forecasts for laboratory procedures. In a one year out of sample evaluation, the annual percent forecast error was 0.7% for the regression model. This compares favorably to a percentage forecast error of 11.6% using subjective forecasting methods.

Forecasting↗

Effects of long-acting somatostatin analog (SMS 201-995) on eicosanoid synthesis and survival in rats with acute necrotizing pancreatitis.

The effects of a long-acting somatostatin analog (SMS 201-995) were studied in an established model of acute necrotizing pancreatitis in rats. SMS 201-995, when given prior to induction of pancreatitis, decreased the mortality rate from 100% to 40% (P = 0.0001). When treatment was given after induction of pancreatitis, the mortality rate was 75% (P = 0.2). Administration of SMS 201-995 did not influence the serum concentrations of amylase markedly, but the lipase levels were significantly lowered (P less than 0.05). The low levels of serum insulin and the glucose level in whole blood were not influenced. The volume of ascitic fluid was reduced (P less than 0.01). Moreover, less peritoneal fat necrosis was seen, suggesting a reduction in toxic factors in the ascitic fluid. Treatment with SMS 201-995 prior to induction of pancreatitis caused a significant increase in the levels of circulating 6-keto-PGF1 alpha, the stable metabolite of prostaglandin I2 (P less than 0.01). The levels of thromboxane B2 and prostaglandin E2 did not change significantly. The present data support the hypothesis that SMS 201-995 is an activator of prostaglandin I2, thereby modifying the course of the disease.

6-Ketoprostaglandin F1 alpha↗

The role of iron in experimental porphyria and porphyria cutanea tarda.

Porphyria cutanea tarda (PCT) and experimental porphyria are characterized by a decreased activity of the enzyme uroporphyrinogen decarboxylase, and accumulation of uroporphyrins and heptacarboxylporphyrins in the liver. Iron (Fe) plays an important role in PCT and experimental porphyria. Biochemically and electron microscopically, we examined the relationship between Fe and porphyrins in liver tissue of C57BL/10 mice made porphyric by administration of iron dextran as Imferon (IMF), and in liver biopsies of patients with symptomatic PCT. Accumulation of uroporphyrins and heptacarboxylporphyrins, and an increased amount of Fe were observed in livers of mice treated with IMF and in liver biopsies of patients with PCT. In mice treated with IMF, the activity of uroporphyrinogen decarboxylase was decreased. Both in livers of mice treated with IMF and in livers of patients with PCT, needle-like structures, representing uroporphyrin crystals, were observed by electron microscopy. Uroporphyrin crystals and Fe (as ferritin) were observed in the same hepatocyte. Moreover, there was a striking morphological correlation between uroporphyrin crystals and ferritin-Fe, suggesting a role for (ferritin-)Fe in the pathogenesis of porphyria.

Animals↗

Selective accumulation of endogenously produced porphyrins in a liver metastasis model in rats.

The possibility of using the porphyrin precursor 5-aminolevulinic acid to cause selective porphyrin accumulation in tumors was examined. Syngeneic colon carcinomas CC531 were implanted in the livers of Wag/Rij rats. Groups of three to six animals each were given 2 mg/mL of 5-aminolevulinic acid in drinking water from the 8th, 14th, or 17th day after tumor implantation. Two other groups received either 2.5 or 5 mg/kg of Photofrin II (Photomedica Inc., Raritan, NJ) intravenously on day 17. On day 19 the livers were removed and porphyrin concentrations were measured in normal livers and tumors by solvent extraction and high-performance liquid chromatography. Protoporphyrin accumulated progressively in tumors with increasing duration of 5-aminolevulinic acid administration (P = 0.0001), whereas no increase was found in normal livers. After 11 days of 5-aminolevulinic acid administration the porphyrin concentration ratio between tumors and livers was 4:1. In contrast, after Photofrin II administration the concentration was higher in normal livers than in tumors (1:3 ratio, tumor to liver). Enzyme measurements showed a threefold decrease in ferrochelatase activity in tumors compared with livers (P less than 0.001). In conclusion, oral administration of 5-aminolevulinic acid results in progressive accumulation of protoporphyrin in a transplantable colon carcinoma without accumulation in the surrounding liver tissue. This selective accumulation of porphyrins appears to be caused by a relative ferrochelatase deficiency in malignant tissue. 5-Aminolevulinic acid administration may be a suitable approach to photosensitizing liver tumors for photodynamic therapy or to early detection of tumors by fluorescence in ultraviolet light.

Aminolevulinic Acid↗

Disseminated intravascular coagulation in liver cirrhosis.

UNLABELLED: We measured thrombin-antithrombin III complex (TAT), soluble fibrin (SF) and D-dimer levels in 51 patients with liver cirrhosis to determine whether these tests provide new evidence for the presence of disseminated intravascular coagulation (DIC) in liver cirrhosis. TAT levels (median, range) were increased in the patient group (4.2 micrograms/l, 1.8-60.0) compared to the reference group (2.0 micrograms/l, range 1.5-7.6 micrograms/l). SF levels (0 nmol/l, range 0-80 nmol/l) were also increased in the patients as compared to the controls (0 nmol/l, 0), but there was no correlation between TAT and SF levels (r = 0.23, p less than 0.98). TAT levels did not correlate with AT-III levels (r = -0.36, p less than 0.49), but there was an inverse correlation between SF and AT-III (r = 0.60, p less than 0.001). If AT-III levels were above 0.30 U/ml, SF levels remained low, whereas SF levels were increased in patients with AT-III levels below 0.30 U/ml. These findings suggest that if sufficient AT-III is present, thrombin formation is adequately controlled, whereas at low levels of AT-III, thrombin escapes inactivation by AT-III and may act upon fibrinogen, leading to the formation of SF and a low-grade DIC. SF levels correlated well with D-dimer levels (r = 0.55, p less than 0.001), which is consistent with DIC and secondary fibrinolysis. IN CONCLUSION: (1) thrombin formation is increased in liver cirrhosis, as indicated by increased TAT levels in 21 of 51 patients; (2) the plasma concentration of AT-III appears to be of major importance for the development of DIC. The present study provides evidence for DIC in severe liver cirrhosis when AT-III levels are less than 0.30 U/ml.

Adult↗

The validity of bioelectrical impedance analysis in estimating total body water in patients with cirrhosis.

This study assessed the validity of bioelectrical impedance analysis (BIA) to predict total body water (TBW) in patients with cirrhosis. TBW was estimated by deuterium oxide dilution (D2O) and compared with TBW predicted by BIA in 27 patients with cirrhosis with and without ascites or edema (Group A), in a subgroup of 18 'dry' cirrhotics without clinical signs of fluid overload (Group B) and in 27 healthy controls. Three different BIA regression equations were used. In all three groups of subjects high correlation coefficients were obtained between D2O-TBW and BIA-TBW (r > 0.88). In the cirrhotic Group A, BIA significantly underpredicted D2O-TBW by all 3 equations (2.9-3.8 l) and the regression lines were different from the lines of identity by two equations. Standard errors of estimate were high in Group A (3.04-3.97 l) in comparison with Group B (1.79-2.46 l) and the controls (1.03-1.41 l). In the 'dry' cirrhotics (Group B) and in the controls, TBW was correctly predicted by two of three BIA equations, and regression lines were not significantly different from lines of identity. Correlation coefficients in Group B were higher than in Group A (r = 0.96-0.97 vs. 0.89-0.92) and were comparable with controls (r = 0.98-0.99). We conclude that BIA is not a valid method of estimating TBW in cirrhotic patients with ascites and edema. In cirrhotic patients without clinical signs of fluid overload BIA can be used to predict TBW, although accuracy is slightly lower than in healthy controls.

Ascites↗

The art of physical diagnosis.

Preservation of the art of physical examination of food animals is warranted because veterinarians are still asked to assess sick valuable individuals as well as sick animals that may be representative of herd or flock problems. It is very important to establish a consistent, thorough routine for physical and rectal examination to ensure that no problems are overlooked. An example of a routine for examining dairy cattle is presented, as is a sample form for recording findings.

Animal Diseases↗

Endoscopic papillotomy in biliary tract pain and fluctuating cholestasis with common bile duct dilatation and small gallbladder stones.

In patients suspected of having functional disorders of the papilla it is often difficult to establish the indications whether or not to perform endoscopic papillotomy (EP). We report on thirty-two consecutive patients referred for endoscopic retrograde cholangiopancreatography who all had longstanding biliary tract pain and episodes of liver enzyme elevation indicating cholestasis. Further features were: 1) a dilated common bile duct (CBD) after cholecystectomy (n = 11) or 2) a dilated CBD without or with larger (greater than cystic duct diameter) gallbladder stones (n = 6) or 3) multiple small gallbladder stones, with a normal or dilated CBD, in patients with signs of acute gallstone pancreatitis or in whom elective cholecystectomy was not indicated (n = 15). No CBD stones, organic obstruction or other disorders were found in these patients. Without further diagnostic procedures, EP was routinely performed. The laboratory (up to 3 months) and clinical findings (2 to 4 years follow up) showed improvement in all patients undergoing EP. We conclude that immediate EP appears justified in these selected patients.

Aged↗

Whole-body and segmental bioelectrical-impedance analysis in patients with cirrhosis of the liver: changes after treatment of ascites.

Bioelectrical impedance analysis (BIA) is a simple technique for determining body water and calculating body composition. It has been validated in healthy control subjects but not in patients with liver disease. We examined the ability of BIA to detect changes in total body water (TBW) due to removal of ascites. In 12 cirrhotic patients, BIA of the whole body and of body segments was performed before and after treatment of ascites with paracentesis (n = 12) and diuretics (n = 2). TBW changes predicted by BIA, by using two prediction equations, were significantly less than body weight changes (51% and 45% of the weight loss). BIA of body segments showed highly significant changes in both the trunk and the leg and small changes in the arm. These data indicate that BIA of the whole body is not a suitable technique for monitoring fluid changes in cirrhotic patients with ascites. Changes in BIA of body segments may be due to mobilization of edema after the removal of ascites.

Adult↗

Body composition in growth hormone-deficient adults.

Body composition in a group of growth hormone (GH)-deficient adults was compared with a control group matched for age, sex, body height, body weight, and body mass index by using bioelectrical impedance and deuterium oxide-dilution methods and hydrodensitometry. The body-fat percentages of GH-deficient adults were higher despite comparable weight, height, age, and body mass index. Body impedance was higher in the GH-deficient adults after correction for differences in height and fat-free mass. As a consequence, prediction formulas for body composition from body impedance developed in normal subjects cannot be applied to GH-deficient subjects. The higher body impedance in the GH-deficient subjects can be ascribed to a smaller amount of extracellular water in these subjects than in control subjects.

Adipose Tissue↗

The effect of growth hormone administration in growth hormone deficient adults on bone, protein, carbohydrate and lipid homeostasis, as well as on body composition.

OBJECTIVE: The effect on bone, protein, carbohydrate and lipid homeostasis as well as body composition of the administration of growth hormone to adult patients with growth hormone deficiency was studied. DESIGN: Growth hormone was administered at a dose of 25 micrograms/kg/day with a maximum of 1.48 mg (4 IU) a day, for 6 months in eight adults. Studies were done before the start and at 1, 3 and 6 months during therapy, as well as 3 months after treatment had been stopped. RESULTS: Subjective well-being as assessed by a short psychological tests showed an improvement in six and no change in two patients. Body composition, as assessed by body impedance assessment and D2O dilution, both showed an increase in lean body mass of 4 kg (5% of body weight), accompanied by a decrease in mean fat mass of 3 kg. Nitrogen turnover studies showed a transient increase in fed state nitrogen balance due to an increase in the rate of protein synthesis, which exceeded a smaller increase in the protein degradation rate. Growth hormone treatment did not affect the circulating levels of 25(OH)-vitD or PTH 1-84, while 1,25(OH)2-vitD had significantly increased after 6 months, as well as 3 months after treatment ended. Osteocalcin, procollagen I levels, as well as 24-hour urinary excretion of hydroxyproline and calcium rose during growth hormone administration but subsequently decreased rapidly after administration had been stopped, while the increase in alkaline phosphatase persisted. This increase in markers of both bone resorption and bone formation indicates an activation of bone remodelling, but this was not reflected by an increase in bone density. Glucose levels, measured before and during a normal breakfast, increased during growth hormone treatment, but serum insulin levels did not. Total cholesterol levels decreased by 0.5 mmol/l. Levels of T4 and free T4 as well as rT3 decreased, while T3 increased during growth hormone treatment. CONCLUSION: Therapy with growth hormone for 6 months in a dose varying between 6 and 25 micrograms/kg/day increased lean body mass and decreased fat mass. The sense of general well-being improved in most patients. Furthermore, growth hormone treatment increased bone turnover without a measurable increase in bone density, caused some minor changes in lipid and carbohydrate metabolism, and increased the metabolism of thyroxine to T3.

Adult↗