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W Weiss

Publications and source records attributed to W Weiss.

At least 55 records · Page 3Linked to original sources
PubMed1998

Age-related buildup of humoral immunity against epitopes for rosette formation and agglutination in African areas of malaria endemicity.

In this report, we show an age-related buildup of agglutinating activity as well as serum activity against rosette formation in children living in areas of Kenya and Gabon where malaria is endemic. Sera from Kenyans in general exhibited a stronger and wider immune response toward the epitopes, probably reflecting a difference in transmission patterns between the two areas. Thus, our results indicate that repeated malaria attacks in areas of endemicity, and consequently exposure to different isolate-specific antigens, will elicit an antibody-mediated response eventually enabling recognition of the majority of rosetting and agglutinating antigens. The correlation between antirosetting and agglutinating capacity was poor in individual cases, indicating that the rosetting epitopes are only a minor part of the highly diverse surface-exposed antigens (mainly PfEMP1) on the surface of parasitized erythrocytes toward which antibodies may react. These data together with our previous findings that the protection against cerebral malaria correlates with presence of antirosetting antibodies shed new light on our understanding of the gradual acquisition of immunity toward severe complications of malarial infection which children reared in areas of endemicity attain.

Adolescent↗
PubMed1997

Identification and characterization of wheat grain albumin/globulin allergens.

Bakers' asthma, an immediate-type allergic response to the inhalation of cereal flours, is an important occupational disease among workers of the baking and milling industries, and the salt-soluble proteins of wheat and rye flour dust are considered the most relevant allergens. In order to identify and characterize the major IgE-binding proteins, the polypeptide composition of the albumin/globulin protein fraction obtained from different cultivars was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and high-resolution two-dimensional polyacrylamide gel electrophoresis with immobilized pH gradients in the first dimension (IPG-Dalt), followed by immunoblotting with sera from asthmatic bakers. Relevant allergens were isolated by micropreparative IPG-Dalt and blotting onto polyvinylidenedifluoride membranes and identified by amino acid composition analysis or N-terminal amino acid sequence analysis. SDS-PAGE, IPG-Dalt, and immunoblotting demonstrated that the sera of the bakers allergic to flour contained IgE antibodies which bound to numerous albumin/globulin polypeptides in the 70, 55, 35, 26-28, and 14-18 kDa areas. More detailed investigations using IPG-Dalt revealed cultivar-specific differences in IgE-binding. It was also demonstrated that the majority of the allergens were not single polypeptide spots, but consisted of up to ten isoforms of similar molecular mass but different isoelectric points. Amino acid composition analysis and N-terminal amino acid sequence analysis, which were performed for nine allergens located in the 14-18, 26-28, and 35 kDa areas, revealed homologies to amylase/protease inhibitors, acyl-CoA oxidase and fructose-bisphosphate-aldolase from wheat, barley, maize, and rice, respectively.

Albumins↗
PubMed1997

Prevalence of Epstein-Barr viral sequences and EBV LMP1 oncogene deletions in Burkitt's lymphoma from Pakistan: epidemiological correlations.

To investigate the potential relationship of socioeconomic status with the prevalence of Epstein-Barr virus (EBV) and to understand the significance of del-LMP-1 within EBV+ cases of Burkitt's lymphoma (BL), we studied 10 cases of BL, 30 cases of diffuse large cell lymphoma (DLCL) arising in nonimmunocompromised patients, and 30 reactive tonsillar biopsy specimens from Pakistan. Each lymphoma was analyzed for EBV by EBER1 RNA in situ hybridization (EBV-RISH). Cases showing hybridization signal within neoplastic cells and all reactive tonsillar tissues were analyzed for EBV strain type by EBNA-2 polymerase chain reaction (PCR) and for the presence of a del-LMP-1 by PCR. Eight of 10 (80%) of BL were EBV+, each containing EBV strain A and a wild-type LMP-1 gene. In contrast, only 4 of 30 DLCL (13%) cases were EBV positive (three strain A, one strain B), each containing a wild-type LMP-1 gene. Fifteen of 30 tonsillar biopsy specimens contained EBV, all of which were strain A and wild-type for LMP1. The prevalence of EBV in BL from Pakistan is slightly lower than in BL in endemic regions, but significantly higher than in BL in North America. EBV positivity probably reflects the socioeconomic status of the patient population and age at seroconversion. The absence of del-LMP-1 within all EBV+ BL cases is consistent with the view that del-LMP-1 is not involved in the pathogenesis of BL, and the presence of del-LMP-1 in EBV+ cases of BL reported in other studies may likely reflect the prevalence of a viral strain containing the 30-bp deletion within the respective population studied.

Adolescent↗
PubMed1997

Clinical outcome two years after implantation of a transjugular intrahepatic portosystemic shunt for recurrent variceal bleeding.

OBJECTIVE: Implantation of a transjugular intrahepatic portosystemic shunt (TIPS) is a relatively new therapy for variceal bleeding. The aim of this study was to assess clinical course 2 years after TIPS procedure. DESIGN: The study was designed as a prospective, uncontrolled cohort study. METHODS: Forty-six patients who underwent successful TIPS implantation were followed prospectively by clinical examinations, duplex sonography and portal venography. Mean follow-up in surviving patients was 24.1 +/- 9.0 months. RESULTS: The cumulative rate of survival was 80.4% at 1 year and 70.2% at 2 years. The cumulative rebleeding rate was 12.4% at 1 year and 21.3% at 2 years. The mortality rate of episodes of variceal rebleeding was 22.2%. Variceal rebleeding was associated with shunt abnormalities, and successful shunt revision resulted in control of the bleeding. The cumulative incidence of shunt stenosis or occlusion was 41.2% at 1 year and 54.9% at 2 years. Of those patients without shunt abnormalities after 1 year, 23.3% developed shunt stenosis or occlusion during the second year after TIPS procedure. Shunt revision was successful in 96.6% of cases. Secondary patency rate was 88.1% after 2 years. CONCLUSION: Successful TIPS implantation results in a low rate of morbidity and mortality from variceal rebleeding over 2 years. TIPS creation in combination with careful follow-up examinations represents an effective long-term treatment of recurrent variceal bleeding. Even in patients in whom no shunt abnormality is detected during the first year, routine duplex follow-up examinations should be continued at 3-month intervals.

Adult↗
PubMed1997

An epidemic of lung cancer due to chloromethyl ethers. 30 years of observation.

A cohort of 125 chemical workers was established in 1963 to investigate an epidemic of lung cancer caused by industrial exposure to chloromethyl ethers (CME). Ninety-three of the men were exposed to CME, and approximate estimates of exposure were made. Standardized mortality ratios (SMRs) were calculated for lung cancer, based on Philadelphia city rates. Over 30 years of observation, 25 of 67 deaths were due to lung cancer, with a dose-response relationship. SMRs were elevated only among 59 moderately and heavily exposed workers, peaked at 23.1 in the first decade, and then declined to 7.4 and 7.9 in later decades. The mean latency period from onset of exposure to death was 21 to 25 years and was inversely related to cumulative exposure. Three of 12 heavily exposed cases occurred in nonsmokers. Small cell carcinoma accounted for 80% of the moderately and heavily exposed cases.

Adult↗
PubMed1997

Rapid thrombectomy with a hydrodynamic catheter: results from a prospective, multicenter trial.

PURPOSE: To evaluate efficacy and safety of a hydrodynamic rheolytic thrombectomy device for rapid percutaneous treatment of acute thromboembolic occlusions of native lower-extremity arteries and bypass grafts. MATERIALS AND METHODS: In 50 patients, thrombectomy was performed with the rheolytic catheter at four centers. Patients had acute occlusions of native lower-extremity arteries (n = 39) or acute thrombosis of lower-limb bypass grafts (n = 11). Estimated occlusion age was 5 days +/- 5. Mean thrombus length was 15 cm +/- 11. Clinical success was measured on a scale of -3 (deterioration) to +3 (improvement) with established criteria. RESULTS: With the thrombectomy catheter, the majority of thrombus material was removed and antegrade blood flow was reestablished in 45 (90%) patients. Technical success (residual luminal narrowing < 50%) was 52% with use of the device alone. Adjunctive therapy was performed in 45 patients. Clinical improvement after intervention was +3 in 25 (50%) patients, +2 in 10 (20%), +1 in six (12%), and 0 (no improvement) in nine (18%). Clinically unimportant complications related to use of the device were one (2%) distal embolization and two (4%) dissections. Laboratory analysis revealed hemolysis without clinical sequelae. Primary patency rates were 76% after 30 days, 74% after 3 months, and 69% after 1 year. CONCLUSION: The hydrodynamic catheter appears to be safe and effective for rapid thrombectomy.

Aged↗
PubMed1997

Cigarette smoking and lung cancer trends. A light at the end of the tunnel?

OBJECTIVE: To update the epidemic curves for lung cancer in the United States by gender in relation to the temporal trends in adult current cigarette smoking prevalence. METHODS: The design of the study was ecologic, based on population figures. Available data on the prevalence of current cigarette smoking from 1920 to 1990 were plotted in conjunction with age-adjusted lung cancer mortality rates from 1930 to 1992 for each sex. RESULTS: There was a strong temporal relationship between the curves for cigarette smoking prevalence and lung cancer mortality rate with approximately a 30-year population latency period in both men and women. The curves occurred later in women than in men. The lung cancer rate in men peaked in 1990 and then began to decline while the rate in women continued to rise. CONCLUSIONS: The temporal association between cigarette smoking prevalence and lung cancer mortality provides additional support for the causal relationship between smoking and lung cancer.

Adult↗
PubMed1997

Acute and chronic complications after implantation of a transjugular intrahepatic portosystemic shunt--a prospective study in 53 patients.

Implantation of a transjugular intrahepatic portosystemic shunt (TIPS) is associated with a broad spectrum of acute and chronic complications. Data concerning incidence and prognosis of these complications are conflicting but of great importance toward defining the role of TIPS relative to other therapeutic options. We conducted a prospective, uncontrolled cohort study in 53 patients to assess incidence, management and clinical outcome of complications occurring after TIPS procedure. Mean follow-up was 21.1 +/- 9.0 months. Technique-related mortality was 2%; 9% of patients died within 30 days after TIPS procedure. The overall survival rate after 18 months was 74%. The overall incidence of primary hepatic encephalopathy (HE) within the first year was 25%, and 77% of episodes could be managed successfully by medical treatment or implantation of a reducing stent. The rate of patients without rebleeding after 18 months was 84%. Rebleeding was associated with shunt abnormalities, and the bleeding was controlled by revision of the stent. Two patients died of variceal hemorrhage. The cumulative incidence of shunt stenosis or occlusion was 47% after 18 months. The technical success rate of shunt revision was 97%. TIPS implantation is associated with a considerable risk of HE and shunt stenosis or occlusion. Nevertheless most episodes of HE can be managed by medical treatment or implantation of a reducing stent. Angiographic revision of the stent is successful in nearly all cases of stenosis or occlusion. We therefore conclude that TIPS implantation in combination with careful follow-up examinations constitutes effective medium-term treatment of portal hypertension in a considerable proportion of patients.

Acute Disease↗
PubMed1996

[Acute hepatitis as the leading symptom of secondary syphilis].

HISTORY AND CLINICAL FINDINGS: A 44-year-old heterosexual man reported having been jaundiced for 4 days. He drank little alcohol. There was no history of venereal disease. INVESTIGATIONS: Laboratory tests indicated marked cholestasis (alkaline phosphatase 1589 U/I, gamma-GT 449 U/I), but only moderately raised transaminases (GOT 66 U/I, GPT 230 U/I), with a bilirubin level of 4.8 mg/dl. Ultrasonography revealed diffuse parenchymal damage in the liver, while endoscopic retrograde cholangiopancreatography showed no abnormalities. Viral hepatitis was excluded by serological tests. Histology of a liver biopsy showed inflammatory infiltration of the portal areas and of the liver parenchyma. Routine syphilis serology indicated fresh infection with Treponema pallidum. There was a healing painless ulcer in the area of the sulcus coronarius of the genitals. TREATMENT AND COURSE: 2.4 mill. I.U. benzathine benzylpenicillin were administered intramuscularly. This rapidly improved his condition and liver function tests became normal. CONCLUSION: In case of hepatitis of uncertain genesis syphilis should be considered as a possible cause, even in the absence of other signs of the disease.

Acute Disease↗
PubMed1996

Epidemiology of fibrous glass and lung cancer.

In a recent commentary, Infante et al. [1994] summarized some of the epidemiologic literature on the relationship between glass wool and lung cancer. They concluded that this material is carcinogenic for the lung in humans. A review of the commentary in comparison with the original papers covered reveals that their analysis was incomplete and characterized by selection bias. A more careful examination of the literature cited and other relevant publications shows that the data cited by Infante et al. are subject to the errors of chance and confounding and that the association when present is inconsistent, weak, and lacks a dose-response relationship. Therefore, a conclusion of causality cannot be justified.

Animals↗
PubMed1995

Identification of T and B cell epitopes recognized by humans in the C-terminal 42-kDa domain of the Plasmodium falciparum merozoite surface protein (MSP)-1.

The 42-kDa, C-terminal region of the merozoite surface protein-1 (MSP-1) of Plasmodium falciparum is a putative malaria vaccine candidate Ag. Nine synthetic peptides corresponding to predicted T cell sites of MSP-1 in blocks 15 and 16 and eight overlapping peptides representing the conserved block 17 were used to identify naturally immunogenic epitopes. These peptides were tested for their ability to induce proliferation of PBMC from residents in western Kenya, where malaria transmission is holoendemic. Six peptides (PL145, PL146, PL147, PL148, PL149, and PL150) from blocks 15 and 16 induced a positive proliferative response in > 30% of the individuals tested, and three peptides (PL151, PL152, and PL153) induced a proliferative response in < 25% of the donors. Among these peptides, PL146 was from the highly conserved region, PL150 was from a polymorphic region, and all other peptides were from a dimorphic region of blocks 15 and 16. In block 17, only three peptides, PL99, PL100, and PL103, induced proliferation in 30 to 37% of the volunteers. The rest of the peptides induced a proliferative response in approximately 13 to 25% of the donors. The plasma from these donors widely reacted with different allelic forms of 19-kDa recombinant proteins representing block 17 and recognized at least two linear B epitopes, PL104 and PL97. In summary, this study revealed that a majority of immunodominant T and B epitopes are localized in the conserved or dimorphic regions that are nonpolymorphic in the 42-kDa protein of MSP-1. This study suggests that incorporation of T epitopes from the dimorphic blocks 15 and 16 in a vaccine construct may be useful to ensure Ag-specific memory responses.

Amino Acid Sequence↗
PubMed1995

Two-dimensional polyacrylamide gel electrophoresis with immobilized pH gradients in the first dimension (IPG-Dalt): the state of the art and the controversy of vertical versus horizontal systems.

After having established the basic protocol of two-dimensional electrophoresis with immobilized pH gradients in the first dimension (IPG-Dalt) in 1988 (A. Görg et al., Electrophoresis 1988, 9, 531-546), some critical parameters of the actual IPG-Dalt protocols as well as the results obtained with horizontal and vertical second-dimensional sodium dodecyl sulfate-electrophoresis are demonstrated and discussed.

Animals↗
PubMed1995

Sequence analysis of wheat grain allergens separated by two-dimensional electrophoresis with immobilized pH gradients.

Micropreparative two-dimensional (2-D) gel electrophoresis with immobilized pH gradients (4-8) in the first dimension (IPG-DALT) was optimized for the separation of salt-soluble wheat grain proteins, associated with bakers' asthma disease. The resolved polypeptides were electroblotted onto a polyvinylidene difluoride (PVDF) membrane and incubated with the pooled sera from four asthmatic bakers. Bound IgE was demonstrated by alkaline phosphatase conjugated anti-human IgE. Major IgE binding was detected in the 27 kDa, 37 kDa and, to a lesser extent, in the 14-18 kDa area of the 2-D immunoblots, respectively. Since the main purpose of our study was to determine the N-terminal amino acid sequences of the major wheat grain allergens, N-terminal sequencing was performed for six out of a total of eleven major allergens located in the 27 kDa area, for one out of two 37 kDa allergens, and for two out of four 14-18 kDa allergens. Our results revealed that two of the 27 kDa polypeptides are clearly related to several Acyl-CoA oxidase variants of barley and rice, whereas no significant homologies were found for the remaining four 27 kDa allergens analyzed. The N-terminus of the 37 kDa allergen appeared to be blocked so that no sequence information was obtained, while the two 14-18 kDa allergens analyzed were identified as members of the wheat alpha-amylase-inhibitor family.

Allergens↗
PubMed1995

The pancreas as a site of granulomatous inflammation in Crohn's disease.

Several reports on the occurrence of pancreatic dysfunction complicating Crohn's disease have been published during the past few years. Nevertheless, the pathogenesis of these disorders remains controversial. In this report, we describe a patient presenting with extrahepatic cholestasis and a mass in the head of the pancreas. Histological examination showed a granulomatous inflammation caused by Crohn's disease involving the stomach, the duodenum, and the head of the pancreas, clearly showing that the pancreas can also be a localization of Crohn's disease. Granulomatous inflammation could be an important factor in the pathogenesis of pancreatic dysfunction occurring in association with Crohn's disease.

Aged↗
PubMed1995

Stavudine in patients with AIDS and AIDS-related complex: AIDS clinical trials group 089.

In a phase I trial of stavudine in AIDS or AIDS-related complex (ARC), antiviral effects and safety were assessed in 41 patients treated with dosages of 0.5-12.0 mg/kg/day. Among evaluable patients, 10% increases in CD4 lymphocyte counts were sustained in 24 (60%) of 40 during treatment; an NAUC response (normalized area under the CD4 cell count-versus-time curve > 1.0) was observed in 31 (91%) of 34 at 10 weeks and in 20 (80%) of 25 at 24 weeks; 15 (83%) of 18 had decreases in p24 antigenemia; and 24 (60%) of 40 gained > or = 2.5 kg body weight. Median CD4 lymphocyte levels remained above baseline for 6 months in patients receiving > 0.5 mg/kg/day. Median serum p24 antigen levels remained below baseline for > or = 1 year in patients with p24 antigen responses. The principal toxicity was peripheral neuropathy, which generally resolved after drug discontinuation but limited the dosage to < or = 2.0 mg/kg/day. Additional trials assessing the effect of stavudine on overall morbidity and mortality are ongoing.

AIDS-Related Complex↗