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H Weiss

Publications and source records attributed to H Weiss.

At least 37 records · Page 2Linked to original sources
PubMed2001

The effect of isolated soy protein on plasma biomarkers in elderly men with elevated serum prostate specific antigen.

PURPOSE: We performed a randomized double-blind crossover pilot study in elderly men with elevated prostate specific antigen (PSA) on the effects of the daily consumption of 2 soy beverages, each containing 20 gm. of isolated soy protein, on the isoflavone concentration in blood and urine, and on the 3 serum biomarkers cholesterol, PSA and the soluble p105 component of the p185erbB-2 proto-oncogene. MATERIALS AND METHODS: A total of 34 men supplemented their diet by consuming 1 of 2 soy protein beverages assigned randomly twice daily for a 6-week period. In a second 6-week period they consumed the other soy protein beverage. The beverage ISP+ provided 42 mg. of genistein and 27 mg. of daidzein daily, whereas the other beverage, ISP-, provided only 2.1 and 1.3 mg. of these isoflavones daily, respectively. Blood and 24-hour urine samples were obtained before the study, at 2-week intervals during the study and 2 weeks after study completion. RESULTS: ISP+ and to a lesser extent ISP- substantially increased the serum concentration and urinary output of the isoflavones and their metabolites. Serum cholesterol was significantly decreased by ISP+ irrespective of the order in which the 2 soy beverages were administered and in apparent correlation with the total isoflavone concentration. There was no significant effect of the soy beverages on serum PSA and p105erbB-2 values. CONCLUSIONS: This study reveals that short-term exposure of elderly men with elevated serum PSA values to soy protein containing isoflavones decreases serum cholesterol but not the serum biomarkers PSA and p105erbB-2.

Aged↗
PubMed2001

Improved scintigraphic assessment of occult leakages in adjustable gastric bands using 99mTc-labelled human albumin colloid.

BACKGROUND: Adjustable gastric banding has become the preferred procedure in Europe for the treatment of morbid obesity. A complication of this treatment is the presence of leakage in the system. The knowledge of the localization of the leak is essential for planning the reoperation procedure. PATIENTS AND METHODS: In a series of 325 adjustable gastric bandings, we observed 10 band leakages. In 3 cases, fluoroscopy failed to detect fluid extravasation. We present a sensitive and simple scintigraphic method for the detection of gastric band leakage in these patients using 37 MBq of a 99mTc-human albumin colloid suspension. Imaging was started immediately after the dose application. During the first minute, images were acquired dynamically with 1 frame every 2 seconds. Afterwards, a static image was obtained every 10 minutes, up to 60 minutes post-injection. Then the system was emptied completely to detect tracer extravasation and consecutive reabsorption during 60 minutes. The study was analyzed by using the regions of interest (ROI) technique drawn on the following points: injection reservoir, tube, anterior band, posterior band, and an adjacent region which was taken as background. RESULTS: During the first hour, ROI analysis showed a clear diminution in the number of counts contained in the defect parts of the band, whereas it remained constant in the other locations. After system emptying, detection of tracer extravasation further strengthened the diagnosis of band leakage in all patients. CONCLUSION: This new approach using the 99mTc-human albumin colloid suspension with ROI analysis is an effective and simple method to detect occult leakages in adjustable gastric bands which escaped detection by fluoroscopy. In contrast to previously described scintigraphic methods, this investigation is able to demonstrate the exact site of leakage.

Adult↗
PubMed2001

A study of pain after laparoscopic gastric banding.

BACKGROUND: The introduction of the laparoscopic approach to bariatric surgery has brought similar advantages as those seen in general surgery. There have been no trials assessing postoperative pain after laparoscopic adjustable silicone gastric banding (LASGB). We compared prospectively postoperative pain and outcome in LASGB and laparoscopic cholecystectomy (LC), to determine if morbidly obese patients can expect the same benefits from a laparoscopic approach in gastric banding as those which are known for LC in non-obese and obese patients. METHODS: In a prospectively collected database of 80 patients undergoing LASGB, information including a survey assessing the postoperative pain, the amount of analgetic drugs used, operative reports, laboratory data, and follow-up data was collected. This was compared to an equal number of patients undergoing LC. Postoperatively, all patients received standardized pain medication of 150 mg tramadol per day. Pain was assessed twice on postoperative days 1-3 using a patient questionnaire. RESULTS: Patient characteristics and duration of hospital stay were similar in the two groups. Although there was no significant difference in type and intensity of pain experienced by the patients in either group, the gastric banding patients reported less postoperative pain overall than those in the LC group. CONCLUSION: The analyzed data show that LASGB offers the same advantages as other laparoscopic operations, in that it induces less pain and enables the patient to return quickly to normal activity and work. The advantage over the compared LC group may be due to higher patient motivation, but was not statistically significant.

Adolescent↗
PubMed2001

Is a routine liquid contrast swallow following laparoscopic gastric banding mandatory?

BACKGROUND: The authors assess the value of liquid contrast medium swallow as a method to detect postoperative complications after laparoscopic adjustable gastric banding (LAGB) for the treatment of morbid obesity. METHODS: From January 1996 to January 2001, 350 morbidity obese patients (295 women, 55 men) underwent a LAGB operation. All data were prospectively collected in a computerized databank. All patients underwent a jopomidol swallow (JS) study in the early postoperative phase to exclude perforation of the esophagus or stomach, which is one of the most serious complications occurring after the LAGB operation. Furthermore, the JS was performed to confirm band position and to exclude early pouch dilatation. RESULTS: Out of the 350 LAGB operations, 6(1.8%) early pouch dilatations and 4(1.2%) stomach perforations occurred. All early pouch dilatations were recognized on postoperative JS and immediately repaired laparoscopically. Of the perforations, one was recognized intraoperatively, and the other three were diagnosed postoperatively, either by contrast media extravasation on the JS (two patients) or by computer tomography. CONCLUSION: Presently, all patients undergo routine postoperative JS, which exposes them to radiation, causes patient discomfort, and entails additional costs of approximately 100 US$ per patient. Of the last 250 patients in our series, there have not been any cases of early pouch dilatation and since 1998 only one case of perforation has occurred, which could be easily suspected clinically. Therefore, we believe that in experienced centers, it is not necessary to perform routine postoperative contrast media studies and recommend JS only in cases of complicated postoperative courses.

Adult↗
PubMed2000

[Prokinetic medication after surgical therapy of reflux patients with disorders of esophageal peristalsis: a randomized clinical study].

BACKGROUND: Long-standing gastroesophageal reflux disease (GERD) is frequently associated with impaired esophageal body motility. Partial posterior fundoplication improves esophageal peristalsis. The aim of this prospective randomized study was to investigate whether administration of the prokinetic agent cisapride enhances this effect. METHODS: Forty consecutive GERD patients with impaired esophageal peristalsis entered the study and were randomized in two groups: group 1 with and group 2 without postoperative treatment with cisapride (6 months, 20 mg twice daily). Four patients had to be excluded during the study. Esophageal motility was analyzed preoperatively and 6 months after surgery by measuring contraction amplitudes in the distal two thirds of the esophagus, frequency of simultaneous and interrupted peristaltic waves and total number of defective propagations. RESULTS: In both groups esophageal peristalsis was improved significantly following partial posterior fundoplication (p < 0.05; Wilcoxon Test). However, this effect was significantly more pronounced in patients receiving cisapride medication postoperatively (p < 0.05; Mann-Whitney U test). Lower esophageal sphincter pressure, intra-abdominal sphincter length and the DeMeester reflux score were normalized in both groups following antireflux surgery. CONCLUSIONS: Partial posterior fundoplication combined with postoperative cisapride medication seems to be the therapy of choice in GERD patients with impaired esophageal body motility.

Adult↗
PubMed2000

Characterization of two novel redox groups in the respiratory NADH:ubiquinone oxidoreductase (complex I).

The proton-pumping NADH:ubiquinone oxidoreductase is the first of the respiratory chain complexes in many bacteria and mitochondria of most eukaryotes. The bacterial complex consists of 14 different subunits. Seven peripheral subunits bear all known redox groups of complex I, namely one FMN and five EPR-detectable iron-sulfur (FeS) clusters. The remaining seven subunits are hydrophobic proteins predicted to fold into 54 alpha-helices across the membrane. Little is known about their function, but they are most likely involved in proton translocation. The mitochondrial complex contains in addition to the homologues of these 14 subunits at least 29 additional proteins that do not directly participate in electron transfer and proton translocation. A novel redox group has been detected in the Neurospora crassa complex, in an amphipathic fragment of the Escherichia coli complex I and in a related hydrogenase and ferredoxin by means of UV/Vis spectroscopy. This group is made up by the two tetranuclear FeS clusters located on NuoI (the bovine TYKY) which have not been detected by EPR spectroscopy yet. Furthermore, we present evidence for the existence of a novel redox group located in the membrane arm of the complex. Partly reduced complex I equilibrated to a redox potential of -150 mV gives a UV/Vis redox difference spectrum that cannot be attributed to the known cofactors. Electrochemical titration of this absorption reveals a midpoint potential of -80 mV. This group is believed to transfer electrons from the high potential FeS cluster to ubiquinone.

Electrochemistry↗
PubMed2000

Cytologic features of proliferative breast disease: a study designed to minimize sampling error.

BACKGROUND: Assessment of cytologic features that allow accurate classification of proliferative breast disease has been hampered by sampling errors when fine-needle aspirations have been compared with their corresponding histologic sections. METHODS: To allow for optimal cytohistologic correlation, 2 smears (1 hematoxylin and eosin-stained and 1 Diff-Quik-stained) were prepared from each of 98 breast biopsies without mass lesions and compared with the corresponding histologic sections of the scraped area. Each smear was reviewed in a blinded fashion and assessed for cellularity, background elements, cytoarchitectural features of cell groups, and nuclear features by 2 reviewers. Smears were then classified as nonproliferative breast disease (NPBD), proliferative breast disease without atypia (PBD) or with atypia (PBDA), or DCIS, based on review of the corresponding histologic sections. RESULTS: When comparing NPBD/PBD (n = 86) with PBDA/DCIS (n = 12), smears from PBDA/DCIS were significantly (by the Fisher exact test or Wilcoxon rank sum P values with adjustment for multiple comparisons) more likely to be cellular; contain single cells and necrosis; exhibit nuclear overlap and cytoplasmic vacuoles; have large nuclei, macronucleoli, pleomorphism, clumped chromatin, and hyperchromasia; and were less likely to have complex cell groups, monolayers, swirling, cohesion, and myoepithelial cells in epithelial sheets and the smear background. When NPBD (n = 53) and PBD (n = 33) were similarly compared, smears from PBD were more likely to exhibit larger and more complex cell groups, but they were otherwise similar to smears from NPBD. CONCLUSIONS: There are many cytologic features that will allow a distinction of NPBD/PBD from PBDA/DCIS, but relatively few that can aid in separating NPBD from PBD.

Biopsy↗
PubMed2000

Mitochondrial calcium overload is restricted to a few mitochondria in endothelial cells after cold ischemia/reperfusion.

Changes in cytosolic and mitochondrial calcium content were studied in an endothelial cell model after simulating cold ischemia reperfusion injury. Image analysis demonstrated that only a subpopulation of mitochondria in endothelial cells accumulate calcium. Observations led to the hypothesis that mitochondria which are in close contact with the plasma membrane are mainly affected by the Ca2+ efflux across that membrane, while those in other parts of the cell remain unaffected.

Adenosine↗
PubMed2000

Associative learning is enhanced by selective neuronal nitric oxide synthase inhibitors and retarded by a nitric oxide donor in the rabbit.

RATIONALE: Previous studies had reported that the nitric oxide (NO) donor, sodium nitroprusside (SNP), retarded and the non-specific NO synthase (NOS) inhibitor, Nomega-nitro-L-arginine methyl ester (L-NAME), enhanced acquisition of classically conditioned responses (CRs). These effects of IV SNP and IP L-NAME on CR acquisition occurred in the absence of any effect on non-associative processes or performance variables and at a time when there were no alterations in blood pressure or heart rate. OBJECTIVES: In this study, we examined whether the changes in associative learning produced by L-NAME and SNP were due to their central effects on NO content of brain. To this end, we examined the effects of the selective neuronal NOS inhibitors 7-nitroindazole (7-NI) and AR-R 17477 and the effects of central (ICV) administration of the NO donor SNP on learning. METHODS: Effects of drugs on CR acquisition were determined during classical conditioning of the rabbit's nictitating membrane (NM) response. Explicitly unpaired presentations of conditioned stimuli (CSs) and unconditioned stimuli (USs) were employed to measure non-associative levels of responding and unconditioned response (UR) topography. RESULTS: The SC injection of 7-NI and AR-R 17477 significantly enhanced associative learning while ICV administration of SNP significantly retarded learning. CONCLUSION: Production of NO within the brain by neuronal NOS normally acts to retard associative learning presumably by decreasing excitability within neuronal circuits involved in the acquisition of the classically conditioned NM reflex.

Amidines↗
PubMed2000

Extent of surgery for intermediate-risk well-differentiated thyroid cancer.

BACKGROUND: Methods of assigning patients with papillary or follicular thyroid cancer (well-differentiated thyroid cancer) to risk groups for the purpose of determining appropriate therapy have been developed. Despite these efforts, the optimal extent of surgery for intermediate-risk patients remains controversial. METHODS: A retrospective study was conducted of 208 patients with well-differentiated thyroid cancer (DTC) from two institutions. Univariate and multivariate analysis of patient- and tumor-related variables was performed. A regression model was obtained, three risk groups (low, intermediate, and high) were defined, and survival curves were generated. RESULTS: Prognostic variables were age (P <0.001), distant metastases (P <0.001), tumor size (P <0.001) and an aggressive growth pattern (P = 0.03) by univariate analysis and age (P <0.001) and distant metastases (P <0.001) by multivariate analysis. Tumor size (P = 0.07) was included in the regression model. Total thyroidectomy appeared to provide a survival advantage for intermediate risk patients. High-risk patients treated by lobectomy had a poorer prognosis. CONCLUSIONS: Total thyroidectomy may provide a survival advantage for intermediate-risk patients with DTC. A prospective randomized trial with 200 such patients is required to confirm this finding.

Adenocarcinoma, Follicular↗
PubMed2000

Chlorobenzenes and hexachlorocyclohexanes (HCHs) in the atmosphere of Bitterfeld and Leipzig (Germany).

Concentrations of tetrachlorobenzenes, pentachlorobenzene, hexachlorobenzene and alpha-, beta-, gamma- and delta-HCH in air and deposition were measured at three different contaminated sites in Greppin, Roitzsch (both near Bitterfeld) and Leipzig during five time intervals of 14 days in the summer months of 1998. The mean values of the chlorobenzene concentrations (gas phase and particle bound portions) over the whole sampling time were 0.11 ng/Nm3 (Leipzig), 0.17 ng/Nm3 (Roitzsch) and 0.37 ng/Nm3 (Greppin), the mean values of the HCH concentrations were 0.22 ng/Nm3 (Leipzig), 0.31 ng/Nm3 (Roitzsch) and 0.69 ng/Nm3 (Greppin). This increase of the concentration values from Leipzig over Roitzsch to Greppin indicates the influences of industrial waste sites in the Bitterfeld region on the atmospheric environment. The significantly higher values of hexachlorobenzene, alpha- and beta-HCH in Greppin are probably caused by emissions from the former chemical plant Bitterfeld-Wolfen and the landfill 'Antonie' near Greppin. Compared with literature data from other industrial impacted areas the measured air concentration and deposition values are relatively low.

Air Pollutants↗
PubMed2000

The expression of Ep-CAM (17-1A) in squamous cell cancers of the lung.

Immunotherapy trials using monoclonal antibodies 323/A3 and 17-1A that recognize Ep-CAM, including trials focused on cancer of the lung, currently are underway. Nevertheless, there have been few comprehensive evaluations of the expression of Ep-CAM in specific types of neoplastic processes, including cancer of the lung. The current study of 60 human subjects with squamous cell cancer (SCC) of the lung, selected at random, was undertaken (1) to examine the expression of Ep-CAM in SCC and associated uninvolved bronchial mucosa, bronchial epithelial hyperplasia, and dysplasia, and (2) to correlate the results with established prognostic indicators and survival of patients. In both the uninvolved bronchial mucosa and epithelial hyperplasia, the expression of Ep-CAM in luminal cells was significantly higher compared with its expression in the matched basal cells (P = .003, P < .0001, respectively). When Ep-CAM scores of basal and luminal cells present in uninvolved bronchial mucosa and epithelial hyperplasia were combined, we observed a statistically significant stepwise increase in Ep-CAM expression from uninvolved bronchial mucosa to epithelial hyperplasia to SCC, suggesting its involvement in malignant transformation of SCC. The expression of Ep-CAM was significantly higher in poorly to moderately differentiated SCC compared with well-differentiated SCC (P = .04). An increase in the expression of Ep-CAM with increasing size or local extent of the primary tumor approached statistical significance (P = .09). The expression of Ep-CAM increased significantly with increasing involvement of regional lymph nodes (P = .02). Similarly, the expression of Ep-CAM increased with the increasing TNM stages (P = .04). Kaplan-Meier Survival analysis using the same categorizations showed that increasing tumor size, nodal status, and stage were significantly associated with poor patient survival (P = .04, .01, .01, respectively). There was, however, no statistically significant association between patient survival and staining intensity of carcinomas for Ep-CAM. We conclude that expression of Ep-CAM increased during the progression of SCC of the lung and, therefore, may play a role in the carcinogenesis of this disease.

Antigens, Neoplasm↗
PubMed2000

The expression of fatty acid synthase (FASE) is an early event in the development and progression of squamous cell carcinoma of the lung.

Correlation of elevated levels of the lipogenic enzyme, fatty acid synthase (FASE), with advanced stages of some cancers has drawn attention to this enzyme as a possible marker of poor prognosis. Because recent studies have shown that cancer cells are dependent on fatty acid synthetic activity and pharmacologic inhibitors of this enzyme are selectively cytotoxic to cancer cells, expression of FASE also may provide a potential target for intervention in the neoplastic process. To determine the potential usefulness of expression of FASE in the neoplastic process of the lung, we evaluated its pattern of expression immunohistochemically in archival specimens from 60 human lung specimens with squamous cell cancer (SCC) and associated "preneoplastic" lesions compared with its expression in the normal bronchial epithelium of 60 noncancer specimens. The expression of FASE was significantly higher in SCC associated uninvolved bronchial epithelium (mean = 0.40+/-0.03, median = 0.38) compared with its expression in the bronchial epithelium of noncancer specimens (mean = 0.18+/-0.02, median = 0.16) indicating its early expression. We also observed a statistically significant step-wise increase in FASE expression from SCC associated uninvolved bronchial epithelium (mean = 0.40+/-0.03, median = 0.38) to epithelial hyperplasia (0.58+/-0.04, median = 0.57) to SCC (1.53+/-0.06, median = 1.50). The results suggested that expression of FASE is an early event in the development and progression of SCC of the lung. The inhibition of fatty acid synthesis by inhibiting enzymatic function with metabolic analogues may be a useful strategy in the treatment of SCCs. The expression of FASE in early lesions such as SCC associated uninvolved bronchial epithelium and epithelial hyperplasia might also provide a potential means for intervention early in the neoplastic process in the lung or even preventing their malignant transformation to invasive carcinomas.

Biomarkers, Tumor↗
PubMed2000

[Sonographic representation of the normal and acute inflamed appendix--in patients wi right-sided abdominal pain].

The detectability, vascularization and size of the normal and inflamed appendix were investigated in the study. 148 patients under suspicion of appendicitis or with lower right abdominal pain were studied over a period of five months beginning in January 1998. An ultrasound-transducer was employed at a wave length of 3.5 MHz to 10 MHz. Vascularization was measured using 'Duplex' and 'Color Angio'. The results were compared with operative evidence, histology and patient history. The appendix was detected in about 30% of the cases (47/148). But of the presumably normal appendices only 12% (13/109) were detected. 27 appendices sonographically diagnosed as acutely inflamed were confirmed by operation and phlegmonic. The acute appendicitis was sonographically diagnosed with a sensitivity of 82% and a specificity of 95%. The diameter of the normal appendices was an average of 5.5 mm, that of the acute was 12.2 mm whereby 21 of 25 organs were at least 9 mm. The measurement of the organ size seems to be more helpful than the detection of vascularization. Both methods alone cannot detect the acute phlegmonic appendicitis. The normal appendix was less frequently detected than described in current literature. Patients with pain present difficulties in ultra-sound examination because both the cooperation and the time for the correct diagnosis are limited.

Abdominal Pain↗
PubMed2000

Prophylactic indomethacin: factors determining permanent ductus arteriosus closure.

BACKGROUND: Permanent closure of the ductus arteriosus (DA) requires both effective muscular constriction to block luminal blood flow and anatomic remodeling to prevent later reopening. OBJECTIVE: We examined the role of prophylactic indomethacin in producing permanent DA closure and the mechanism by which this occurs. METHODS: We studied 2 separate approaches to managing a patent DA in 257 preterm infants (gestation 24 to 27 weeks): (1) prophylactic indomethacin (all infants treated during the first 15 hours after birth) or (2) symptomatic treatment (infants in this group received indomethacin only if clinical symptoms appeared; infants whose ductus closed spontaneously and never received indomethacin were included in this group). Echocardiography was performed 24 to 36 hours after the last dose of indomethacin was administered or by age 5 days if spontaneous closure occurred. Infants were monitored for the development of ductus reopening. RESULTS: The prophylactic treatment group had a greater degree of initial ductus constriction, a higher rate of permanent anatomic closure, and a decreased need for surgical ligation than did the symptomatic treatment group. The degree of initial ductus constriction was the most important factor determining the rate of ductus reopening. Post-treatment echocardiography proved to be the best test for predicting eventual reopening. CONCLUSION: Prophylactic indomethacin improved the rate of permanent ductus closure by increasing the degree of initial constriction. Prophylactic indomethacin did not affect the remodeling process, nor did it alter the inverse relationship between infant maturity and subsequent reopening. Even when managed with prophylactic indomethacin, the rate of ductus reopening remained unacceptably high in the most immature infants.

Cardiovascular Agents↗
PubMed2000

Comparison of two different meat inspection techniques.

Field studies of meat inspection procedures in three different slaughter houses were performed in Germany, in 1996. In total 22,634 fattening pigs from 63 farms were inspected twice, using a visual and the traditional (mandatory inspection system) procedure. Statistical analysis was performed using the rate of ND+ (Non-Detected Positives) for both visual and traditional inspection. Neither the visual nor the traditional methods detected all lesions which were supposed to be in the lot of animals inspected. Some of the results could be explained by the nature and obviousness of the respective lesion. Conclusions regarding the future performance of inspection should not be drawn before a formal risk analysis procedure for the particular lesion has been done.

Abattoirs↗
PubMed2000

Chromosomal rearrangement in autotetraploid plants of Arabidopsis thaliana.

Recent development of cytogenetic techniques has facilitated significant progress in Arabidopsis thaliana karyotype studies. Double-target FISH with rRNA genes provides makers that allow individual chromosome in the genome to be distinguished. Those studies have revealed that the number and position of rDNA loci is ecotype-specific. Arabidopsis is believed to be a true diploid (x = 5) with numerous ecotypes (accessions) and only a very few natural polyploid populations reported. Few studies were undertaken to induce polyploidy in Arabidopsis, however none of those gave the cytogenetic characteristics of polyploid plants. Our analysis of chromosome pairing of colchicine-induced autotetraploid Arabidopsis (Wilna ecotype) revealed preferential bivalent pairing in PMCs (pollen mother cells). In order to attempt to explain this phenomenon, first of all more detailed cytogenetic studies of autopolyploid plants have been undertaken. The localization of 45S and 5S rDNA loci in the diploid and autotetraploid plants revealed that Wilna ecotypes belongs to the group of Arabidopsis accessions with only two 5S rDNA loci present in a genome. Furthermore, the rearrangement of 45S rDNA locus in autopolyploid, when compared to the diploid plants of the same ecotype, was revealed. These results are interesting also in the context of the recently emphasised role of polyploidy in plant evolution and speciation. Arabidopsis, despite having small chromosomes, is a good system to study chromosome behaviour in relation to diploidization of autopolyploids and to evaluate the degree of chromosomal rearrangements during this process.

Arabidopsis↗