Next to tobacco, saccharin may be the substance that has been most studied epidemiologically. Over 5000 patients with bladder cancer have participated in case-control studies; over 27,000 diabetics have been observed for 234,000 person-years. The summary relative risk from combining all case-control studies is less than 0.98, the standardized mortality ratio for bladder cancer in diabetics is only 70. Analysis of these studies leads to the conclusion that saccharin is not related to human bladder cancer.

Humans↗

PubMedDate not supplied

Mortality study of fibrous glass production workers.

This retrospective cohort study examines the mortality experience of 6,536 male employees engaged in fibrous glass production for 10 or more years. A special component of this investigation was an analysis of a long-term cohort involving 1,222 individuals who were employed 20 or more years and who experienced 30 or more years latency. There was no marked excess of statistically significant increase in mortality for any cause of death. In fact, the pattern of mortality for fibrous glass production workers appeared considerably lower than comparable U.S. patterns, perhaps reflecting both a "health worker" effect, and the life style of the steadily employed person. Long-term workers' mortality experience was similar to those individuals employed for shorter periods.

Adult↗

PubMedDate not supplied

Tracking and surveillance of patients with medical devices and implants.

The United States Congress and FDA recently proposed modifications to the regulation for the tracking of certain medical devices and implants that will place significant demands on the manufacturers and importers of those products. The regulation, which comes into effect in August this year, will require the industry to carry out not only tracking of those devices or implants to the end user, but also continued observation of the device user or implant recipient throughout the life of the patient or the device. In this article, the author outlines FDA requirements and advises how best to meet those demands. The important elements for setting up a patient-tracking programme are discussed; these include the use of a Patient Registry as a basis for tracking and the importance of confidentiality throughout the tracking process.

Confidentiality↗

PubMedDate not supplied

Comparison of two serotype 1 MDV isolates.

We compared the RB1B and T. King (TK) serotype 1 isolates of Marek's disease virus (MDV) in vivo. Body and organ weights, mortality, and lesions indicated that the TK inoculum established early infection more efficiently than RB1B and did greater damage to the bursa of Fabricius and thymus. Subsequent studies showed that the TK inoculum that we used contained chicken infectious anemia virus (CIAV). Therefore, pathogenicity profiles shown here should be interpreted with the presence of CIAV contamination in the TK stock in mind.

Animals↗

PubMedDate not supplied

A monoclonal antibody to ICP4 of MDV recognizing ICP4 of serotype 1 and 3 MDV strains.

Monoclonal antibodies (MAbs) were prepared against ICP4 of Marek's disease virus (MDV). Mice were inoculated with ICP4 obtained from High-Five insect cells infected with a recombinant baculovirus expressing ICP4. MAbs were selected by enzyme-linked immunosorbent assay (ELISA) using MDV-infected and control chick kidney cells as antigens. One of the MAbs, 5H8, recognized an epitope toward the carboxyl terminus of ICP4 based on staining of reticuloendotheliosis virus-transformed cells transfected with full-length and truncated ICP4 constructs. This MAb recognized ICP4 in chicken embryo fibroblasts (CEFs) infected with MDV strains JM16 and HVT but not with SB-1 strain. Using Western blot analysis a protein of 155 kDa was detected in CEFs infected with JM16 and HVT strains.

Animals↗

PubMedDate not supplied

Coinfection of specific-pathogen-free chickens with Marek's disease virus (MDV) and chicken infectious anemia virus: effect of MDV pathotype.

Both Marek's disease virus (MDV) and chicken infectious anemia virus (CIAV) infections are prevalent in chickens throughout the world. In the past decade, MDV strains with increased virulence (very virulent plus MDV pathotype [vv+MDV]) have been isolated. The purpose of this experiment was to determine the effects of coinfection of chickens with CIAV and a vv+MDV isolate. Specific-pathogen-free chickens were inoculated at 1 day posthatch with RB1B (very virulent MDV pathotype [vvMDV]) only, 584A (vv+MDV) only, CIAV only, RB1B + CIAV, 584A + CIAV, or nothing. Samples of spleen, thymus, and bursa of Fabricius were collected at 4, 7, 10, and 13 days postinoculation (DPI). Thymic and bursal atrophy at 13 DPI and final mortality at 30 DPI were significantly greater in chickens inoculated with 584A with or without added CIAV, or with RB1B plus CIAV, compared with birds inoculated with RB1B alone. Both amounts of virus reisolated and levels of virus detected by quantitative-competitive polymerase chain reaction were greater at 4 DPI in 584A inoculates compared with RB1B inoculates. To monitor the early cytolytic infection, northern analysis was done with a probe for the MDV immediate early gene ICP4 (infected cell protein 4). In the absence of CIAV, ICP4 expression was more apparent in chickens inoculated with 584A than in those inoculated with RB1B. CIAV coinfection increased ICP4 expression in the spleens of chickens infected with RB1B. These results indicated that inoculation of chickens with the 584A isolate caused a more robust early cytolytic infection compared with inoculation with RB1B alone and support the classification of 584A as a vv+MDV strain. Coinfection with CIAV exacerbated vvMDV strain RB1B infection. The extent of this exacerbation was less evident when birds were coinfected with 584A and CIAV.

Animals↗