Farm tractor safety in Kentucky, 1995

OBJECTIVE

Tractor rollovers are a major cause of farm injuries and fatalities. The authors used data from a statewide surveillance study to estimate the prevalence of safety features such as rollover protective structures, seat belts, and power take-off shields on farm tractors in Kentucky.

METHODS

Using data from the Farm Family Health and Hazard Surveillance Project, the authors report on the prevalence of farm tractor safety features by size of farm, by region of the state, by number of tractors per farm, and by tractor age and estimate the prevalence of tractors equipped with rollover protection by region and for the state as a whole.

RESULTS

Of the estimated 85,446 family-owned farms in Kentucky with at least one tractor, an estimated 55.6%, or 47,515 farms, do not have a tractor equipped with a rollover protective structure. Few tractors that are 10 years old or older were found to be equipped with seat belts; no tractors that were more than 20 years old were equipped with seat belts.

CONCLUSIONS

Kentucky, with an estimated 25 to 30 tractor-related fatalities each year, may contribute up to 20% of the total number of farm tractor fatalities in the nation. The overall prevalence of rollover protective structures on tractors in Kentucky is lower than estimates for other states as reported in national survey data. The study's findings suggest the need to target smaller farms with one or two tractors for retrofitting of rollover protective structures and for tractor safety programs.

Synthesis and secretion of the mouse whey acidic protein in transgenic sheep

The synthesis of foreign proteins can be targeted to the mammary gland of transgenic animals, thus permitting commercial purification of otherwise unavailable proteins from milk. Genetic regulatory elements from the mouse whey acidic protein (WAP) gene have been used successfully to direct expression of transgenes to the mammary gland of mice, goats and pigs. To extend the practical usefulness of WAP promoter-driven fusion genes and further characterize WAP expression in heterologous species, we introduced a 6.8 kb DNA fragment containing the genomic form of the mouse WAP gene into sheep zygotes. Two lines of transgenic sheep were produced. The transgene was expressed in mammary tissue of both lines and intact WAP was secreted into milk at concentrations estimated to range from 100 to 500 mg/litre. Ectopic WAP gene expression was found in salivary gland, spleen, liver, lung, heart muscle, kidney and bone marrow of one founder ewe. WAP RNA was not detected in skeletal muscle and intestine. These data suggest that unlike pigs, sheep may possess nuclear factors in a variety of tissues that interact with WAP regulatory sequences. Though the data presented are based on only two lines, these findings suggest WAP regulatory sequences may not be suitable as control elements for transgenes in sheep bioreactors.

Whey acidic protein extrinsically expressed from the mouse mammary tumor virus long terminal repeat results in hyperplasia of the coagulation gland epithelium and impaired mammary development

The whey acidic protein (WAP) is a milk protein that contains a cysteine-rich motif. This characteristic WAP signature has also been found in some protease inhibitors and certain proteins involved in tissue modeling. WAP is specifically synthesized in mammary tissue from late pregnant and lactating animals, and precocious synthesis results in impaired lobuloalveolar development of the gland in some transgenic lines. To determine whether growth modulatory effects of WAP are confined to mammary tissue, we expressed the WAP gene under the control of the mouse mammary tumor virus long terminal repeat in transgenic mice. The transgene was expressed at high levels in organs with exocrine function, such as mammary and salivary glands, prostate, seminal vesicle, and the coagulation gland. In addition to impaired mammary development, we observed hyperplasia and dysplasia of the coagulation gland epithelium. These findings suggest that WAP or a member of the WAP signature family can, in certain tissue contexts, function as an epithelial growth regulator. It appears from the present study that growth regulatory effects of WAP are restricted in the mouse to the mammary and coagulation gland epithelium.

Direct revascularization of bronchial arteries for lung transplantation: an anatomical study

Direct revascularization of the bronchial arteries for both single-lung and double-lung transplantation would improve airway healing and reduce airway complications after transplantation. We studied the anatomical pattern of bronchial arteries in 30 autopsy cases. In 28 of 30 cases (93.3%), at least one left bronchial artery arose directly from the anterior wall of the descending thoracic aorta. In 25 of the 30 cases (83.3%), at least one right bronchial artery was related to the first right intercostal artery. Injection studies showed that this right intercostobronchial artery supplies the proximal left main bronchus and carina as well as the right bronchus. We developed a technique for extracting the lungs along with the right intercostobronchial artery and a patch of aorta at its origin and applied it to 19 of the dissections. In 17 of the 19 cases studied (89.4%), the right intercostobronchial artery pedicle obtained had a length varying from 6.5 to 8.5 cm, sufficient for attachment of its origin to the ascending aorta of the recipient after double-lung transplantation. The right intercostobronchial artery pedicle provides the possibility for direct bronchial revascularization in right single-lung, double-lung, and lung-heart transplantation. A similar technique, utilizing the left bronchial artery, can be used to revascularize a left lung transplant.

A digestion bomb for wet ashing biological materials

The design and construction of a wet digestion chamber resistant to acids and bases for hard and soft tissues is described. Loss of volatile elements is prevented. Reproducible complete recoveries for a variety of inorganic metal ions are routinely achieved.