Prevalence of monoclonal B-cell lymphocytosis: a systematic review.

Background: Individuals with monoclonal B-cell lymphocytosis (MBL) have been identified in clinic outpatients, in unaffected relatives of patients with chronic lymphocytic leukemia (CLL), and in general populations. MBL and its relationship with CLL have been actively investigated over the last decade. This report systematically reviews the prevalence of MBL in the context of the populations studied and the evolution of laboratory methods used to define MBL.

Monoclonal B-cell lymphocytosis as a biomarker in environmental health studies.

The first studies of monoclonal B-cell lymphocytosis (MBL) in the general population were conducted as part of environmental health investigations that began in 1991. MBL was observed as an unexpected finding when blood samples were immunophenotyped by two-colour flow cytometric methods in common use at that time. The initial observations led to a workshop in 1995, at which case definitions were considered and medical follow-up investigations were recommended.

B cells behaving badly.

The pathogenesis of B-cell lymphoproliferative disorders in general and B-cell chronic lymphocytic leukaemia in particular appears to involve dysfunctional regulation of humoral and cellular immunity with the subsequent development of genetic aberrations in B cells. In theory, either component may arise de novo or may be influenced by environmental exposures including infectious agents, antigens, genotoxic chemicals, or radiation. As an intermediary within the exposure-disease continuum, monoclonal B-cell lymphocytosis may be a helpful biomarker for teasing out these various contributions to risk.

Communicating results to community residents: lessons from recent ATSDR health investigations.

As a public health agency within the US Department of Health and Human Services, the Agency for Toxic Substances and Disease Registry (ATSDR) is responsible for implementing the health-related provisions of the Superfund Act. Much of its work is carried out to address health concerns in communities near sources of environmental contamination, usually in consultation with other local, state, and federal agencies. Over the last decade, ATSDR has considered, supported or conducted health investigations in a variety of different communities across the country.

Ambient hydrogen sulfide, total reduced sulfur, and hospital visits for respiratory diseases in northeast Nebraska, 1998-2000.

This analysis examined associations between total reduced sulfur (TRS) and hydrogen sulfide (H(2)S) levels, and hospital visits for respiratory disease among residents of Dakota City and South Sioux City, Nebraska, from January 1998 to May 2000. For reference, the association between TRS, H(2)S, and digestive diseases was also examined. Time-series analyses of daily hospital visits in the selected outcome categories and measures of TRS and H(2)S were performed using generalized additive models with a Poisson link.

Addressing community concerns about asthma and air toxics.

People with asthma who live near or downwind from a source of toxic emissions commonly express concerns about the possible impact of hazardous air pollution on their health, especially when these emissions are visible or odorous. Citizens frequently turn to their local and state health departments for answers, but health departments face many challenges in addressing these concerns. These challenges include a lack of asthma statistics at the local level, limited exposure information, and a paucity of scientific knowledge about the contributions of hazardous air pollutants to asthma induction or exacerbation.