Enhanced pulmonary epithelial replication and axial airway mucosubstance changes in F344 rats exposed short-term to mainstream cigarette smoke.

Cigarette smoking is associated with respiratory diseases that may be caused by injury to specific pulmonary cells. The injury may manifest itself as site-specific enhanced cellular replication. In this study, rats were exposed either to mainstream cigarette smoke (CS; 250 mg total particulate matter/m(3)) or to filtered air (FA) for 6 h/day, 5 days/week, for 2 weeks. In one group, cells in S-phase were labeled over 7 days by bromodeoxyuridine (BrdU) released from implanted osmotic pumps (pump labeled), while another group received BrdU by injection 2 h prior to necropsy (pulse labeled). Morphometry showed that the type II epithelial BrdU labeling index (LI) was significantly elevated in the CS-exposed animals of both labeling groups. The axial airway and terminal bronchiolar LIs were enhanced by CS only in the pump-labeled group. In a third group (pulse labeled), 2 weeks of recovery following exposure to CS allowed a normalization in the type II LI. In the pump-labeled rats, the CS-induced elevation of the type II LI was greater than the LI elevation in conducting airways, suggesting that the parenchyma may have been injured more than the conducting airways. The terminal bronchiolar LI in the pump-labeled group, regardless of exposure, was significantly greater than the axial airway LI. Pump labeling, in contrast to pulse labeling, could therefore discern differences among replication rates of conducting airway epithelium in different regions of the lung. Mucosubstance (MS) within the axial airway epithelium was quantified by morphometry. The CS exposure did not increase the total number of MS-containing cells or the total number of axial airway epithelial cells, but there was a phenotype change in the MS cells. Neutral MS cells (periodic acid-Schiff-positive) were significantly decreased, while acid MS cells (alcian blue-positive) were slightly increased by CS exposure. Either cell replication and differentiation or differentiation alone may have changed the phenotype in the MS cell population.

Health status and population characteristics of dogs and cats examined at private veterinary practices in the United States.

OBJECTIVE: To determine age, breed, sex, body condition score, and diet of dogs and cats examined at private veterinary practices in the United States during 1995, and estimate prevalences of the most common disorders for these animals. DESIGN: Cross-sectional study. ANIMALS: 31,484 dogs and 15,226 cats examined by veterinary practitioners at 52 private veterinary practices. PROCEDURE: Information on age, breed, sex, body condition score, diet, and assigned diagnostic codes were collected electronically from participating practices and transferred to a relational database. Prevalence estimates and frequencies for population description were generated using statistical software. RESULTS: Dental calculus and gingivitis were the most commonly reported disorders. About 7% of dogs and 10% of cats examined by practitioners during the study were considered healthy. Many conditions were common to both species (e.g., flea infestation, conjunctivitis, diarrhea, vomiting). Dogs were likely to be examined because of lameness, disk disease, lipoma, and allergic dermatitis. Cats were likely to be examined because of renal disease, cystitis, feline urologic syndrome, and inappetence. CLINICAL IMPLICATIONS: Results can be used by veterinary practitioners to better understand and anticipate health problems of importance in cats and dogs they examine and to better communicate with clients regarding the most prevalent disorders in cats and dogs.

Evaluation of vocabularies for electronic laboratory reporting to public health agencies.

Clinical laboratories and clinicians transmit certain laboratory test results to public health agencies as required by state or local law. Most of these surveillance data are currently received by conventional mail or facsimile transmission. The Centers for Disease Control and Prevention (CDC), Council of State and Territorial Epidemiologists, and Association of Public Health Laboratories are preparing to implement surveillance systems that will use existing laboratory information systems to transmit electronic laboratory results to appropriate public health agencies. The authors anticipate that this will improve the reporting efficiency for these laboratories, reduce manual data entry, and greatly increase the timeliness and utility of the data. The vocabulary and messaging standards used should encourage participation in these new electronic reporting systems by minimizing the cost and inconvenience to laboratories while providing for accurate and complete communication of needed data. This article describes public health data requirements and the influence of vocabulary and messaging standards on implementation.