Elephant shrews as hosts of immature ixodid ticks.

Two hundred and seventy-three elephant shrews, consisting of 193 Elephantulus myurus, 67 Elephantulus edwardii and 13 animals belonging to other species, were examined for ixodid ticks at 18 localities in South Africa and Namibia. The immature stages of Ixodes rubicundus, Rhipicentor nuttalli, Rhipicephalus warburtoni and a Rhipicephalus pravus-like tick were the most numerous of the 18 tick species recovered. Substantial numbers of immature Rhipicephalus arnoldi, Rhipicephalus distinctus and Rhipicephalus exophthalmos were also collected from elephant shrews at particular localities. Larvae of I. rubicundus were most numerous on E. myurus in Free State Province from April to July and nymphs from June to October. Larvae of R. nuttalli were most numerous on these animals during April, May, August and September, and nymphs in February and from April to August. The immature stages of R. warburtoni were collected from E. myurus only in Free State Province, and larvae were generally most numerous from December to August and nymphs from April to October.

Understanding factors that influence smoking uptake.

OBJECTIVE: To explore relationships between patterns of smoking uptake and social context and attitudinal variables. DESIGN: Cross sectional survey. SETTING: Public schools in Tucson, Arizona and Albuquerque, New Mexico. PARTICIPANTS: 982 children in grades 6-9 (ages 11-15 years). MAIN OUTCOME MEASURES: Items measuring smoking history, nicotine dependence and quit attempts, susceptibility to smoking in the future, smoking norms, use of other tobacco products, attitudes toward smoking, and demographic characteristics. RESULTS: Overall, 43% of children had smoked a cigarette and 57% had never used them. Ever smokers lived in social contexts with more smoking and where smoking was normative. Among never users, 25% are susceptible to smoking; these children have positive attitudes toward smoking, do not feel social pressure to stay off cigarettes, and had more friends who smoked. Among ever users, 36% were currently smoking in the past 30 days. Current users also lived in social context with more smoking and had positive attitudes toward smoking. Most users had tried to stop smoking. Only 9% of current users smoked daily; 29% had not smoked a whole cigarette. Greater cigarette consumption was associated with more favourable attitudes toward smoking. Most of past users were in early uptake: 95% had smoked less than 100 cigarettes but 49% were susceptible to smoking again. CONCLUSIONS: There is promise in differentiating subgroups among the never, past and current use of cigarettes. Susceptibility within each of these groups was associated with similar patterns of attitudes and social context. These patterns in smoking uptake need to be confirmed prospectively.

Formative research activities to provide Web-based nutrition education to adults in the Upper Rio Grande Valley.

The Internet is a promising new tool for disseminating cancer prevention information. Barriers to full implementation include disparities in access and skill and availability of information relevant at the local level. A nutrition education Web site to promote fruit and vegetable intake is being produced for a tri-ethnic adult population in Colorado and New Mexico. Development is guided by findings from formative research including focus groups with local residents, a survey on computer and Internet use with 200 adults in 1998, an assessment of public access computer sites, and in-depth discussion with local community computer skills trainers.

The chemistry of pseudomonic acid. Part 14. Synthesis and in vivo biological activity of heterocyclyl substituted oxazole derivatives.

Semisynthetic analogues of pseudomonic acid A have been prepared containing a heterocyclyl substituted oxazole. Derivatives in which the heterocycle was thiophene, furan, pyridine, or isoxazole showed good antibacterial potency and were further evaluated in vivo. Both pharmacokinetic parameters and oral activity against an experimental intraperitoneal sepsis were superior to results obtained from previously described pseudomonic acid A derivatives.

Managed health care companies' lobbying frenzy.

The top dozen national managed health care companies and two industry trade groups spent at least $2,023,041 on lobbying expenses and campaign contributions to key lawmakers during last year's health care debate, according to an analysis of Federal Election Commission data and federal lobbying disclosure forms. Five of the top six spenders are large insurance companies that are rapidly transferring their business from traditional indemnity insurance to HMOs. Over half--52 percent--of campaign donations from the top managed care companies' and trade associations' PACs and employees went to members sitting on the five Congressional committees with jurisdiction over health care reform.

Morphology of intestinal villi in African antelope (Artiodactyla: Bovidae).

Villous morphology in 16 species of African antelope varied from finger-like and leaf-like to ridge-like forms. Some species showed uniform villi whereas it was variable in others. There was a slight indication that leaf-like and finger-like forms become more frequent in the distal regions of the small intestine. The variation in morphology was not associated with body size or phylogeny, but did show a significant correlation with diet: species with high moisture content and/or high fibre levels (equivalent to low bulk values) in the digesta were more likely to have ridges, which were the lowest of the villi.

The effect of exercise on the atrial electrogram voltage in young patients.

Atrial electrogram sensing is an important function in active individuals with permanently implanted bipolar dual chamber pacing systems. We undertook to determine the effect of vigorous exercise on the atrial electrogram size in 11 children and young adults (average age 12 years). Using a telemetry signal through a handheld programming wand, nine tracings were completely and clearly recorded for analysis. Six patients had tined/passive fixation atrial leads and three patients had screw-in/active fixation lead systems. All leads were bipolar. The atrial electrogram size for each patient was measured at rest and at each minute of exercise. The atrial electrogram size decreased with exercise from a mean of 5.08 mV to 3.44 mV (range 0.9-4.25 mV) (P = 0.002). The 1.64 mV mean decrease represented a 33.8% reduction (range 19%-56%) (P less than 0.001). There was no difference in the change in atrial electrogram size between the two lead types. Treadmill exercise testing with telemetric data of atrial electrograms showed a decrease in atrial electrogram size produced by exercise and may be helpful in determining appropriate atrial sensitivity settings in selected individuals. Because of the documented decrease in atrial electrogram size produced by exercise, we recommend obtaining maximal atrial electrograms at the time of implant and use of pacing systems that allow maximal flexibility in atrial sensing especially in athletically active individuals.

6-(substituted methylene)penems, potent broad spectrum inhibitors of bacterial beta-lactamase. IV. Kidney stability, serum binding and additional biological evaluation of racemic derivatives.

Sodium (5RS)-Z-6-(substituted methylene)penem-3-carboxylates (3) are extremely potent inhibitors of bacterial beta-lactamases, but some members of this group of compounds are highly bound to human serum, while others are readily degraded by renal dehydropeptidase I enzyme. Consequently, the stability of a variety of 6-(substituted methylene)penems (3) to human kidney homogenate, their binding to human serum and their activity in a mouse infection model was investigated at an early stage, and were instrumental in the selection of the 1,2,3-triazolylmethylene derivatives (e.g. 3k) as a class of compounds worthy of further evaluation.

The effects of increased dietary cellulose on the anatomy, physiology and behaviour of captive water voles, Arvicola terrestris (L.) (Rodentia: Microtinae).

1. Wild water voles and captives on high fibre diets had significantly longer and heavier digestive tracts (especially the caecum) than captives fed a low fibre diet. 2. Increasing dietary cellulose increased food intake, faecal output and metabolic rate, and decreased digestibility. Some but not all added cellulose was digested. 3. The passage of food through the digestive tract was significantly faster on the diet with added cellulose. 4. Coprophagy included eating directly from the anus and eating faecal pellets from the floor of the cage. The frequency of the latter type increased significantly for animals on a high fibre diet.

Periodontal disease in southern African bushpigs (Potamochoerus porcus) and warthogs (Phacochoerus aethiopicus).

Periodontal lesions were found in 14 of 100 bushpig (Potamochoerus porcus) skulls and nine of 103 warthog (Phacochoerus aethiopicus) skulls from southern Africa. The prevalence of periodontal disease showed a significant increase with age in the bushpig but not in the warthog skulls. All the lesions affected the cheek teeth, particularly the molars. The lower prevalence of lesions in older warthogs may be associated with their specialised molars and abrasive diet.

Periodontal disease in feral pigs (Sus scrofa) from Queensland, Australia.

Periodontal lesions were present in 26 of 107 feral pigs (Sus scrofa) that were shot in southern Queensland. The severity of the lesions varied from gingivitis to extensive destruction of the alveolus and its contents. Examination of slaughtered domestic pigs revealed a similar prevalence of lesions (12 of 52). Only cheek teeth were affected, and molars were affected more frequently than premolars. In both feral and domestic pigs, prevalence of periodontal disease affecting bone increased with age. Although periodontal disease is recognized as a common and often serious problem in many mammalian species, both domestic and wild, it has rarely been recorded in the pig. It is considered that the most severe lesions would have interfered with mastication but that the contribution of the disease to mortality of feral pigs in Australia is probably not great.

The rostral nasal anatomy of two elephant shrews.

The nasal anatomy of Elephantulus brachyrhynchus and E. myurus shows adaptations needed for a long, mobile snout with no special chemosensory features. Olfactory and vomeronasal neuroepithelia do not extend rostral to the nasal opening of the incisive ducts. Their fine structure presents no unusual features. Separate dorsal, lateral and ventral cartilages and fenestrations in the septal cartilage permit snout flexibility. Dorsal and ventral tubular glands extend the whole length of the snout under the dermis but only release their secretions at the tip, together with the products of the nasolacrimal and lateral nasal gland ducts. These secretions may protect the bare rostral epithelium from the chemical defences of termites and ants, which are major food items. A ventral groove in the snout communicates directly with the sulcus of the incisive papilla on the rostral palate. The oral openings of the incisive ducts also lie within the sulcus. Variability in the relation of the vomeronasal duct to the incisive duct and in the presence of taste buds on the incisive papilla in the two species of Elephantulus studied here limit their value as evidence of relationships between elephant shrews and other insectivores and prosimians.

Dimensions and allometry of testes, epididymides and spermatozoa in the domestic dog (Canis familiaris).

Dimensions of the testes, epididymides and spermatozoa were measured from a sample of 104, mainly cross-bred, domestic dogs ranging in body mass from 5 to 48 kg. Allometric analyses in relation to body mass indicated isometric changes in testicular mass but epididymal mass and the mass of the cauda epididymidis and sperm numbers in the cauda showed significant positive allometry. Total sperm length, seminiferous tubule diameter and the relative proportion of tissues in the testis showed no significant correlation with body mass, but sperm principal piece length showed a low correlation with body mass. We suggest that the positive allometry of epididymal mass and sperm numbers is related to promiscuous mating and sperm competition in stray dogs.

Caecal size and function in the rock elephant shrew Elephantulus myurus (Insectivora, Macroscelididae) and the Namaqua rock mouse Aethomys namaquensis (Rodentia, Muridae).

1. The relative size of the digestive organs and the function of the caeca of an insectivorous elephant shrew Elephantulus myurus (Macroscelididae) and of a herbivorous rodent Aethomys namaquensis (Muridae) were compared. 2. Both species had similar body mass but A. namaquensis had a significantly heavier total digestive tract, full stomach, and caecum and a longer large intestine and caecum than E. myurus. 3. Both species had similar total volatile fatty acid (VFA) concentration and VFA % composition although A. namaquensis had a significantly higher % of n-butyric acid. Both had a similar caecal NH3-N concentration. 4. The presence of a functional caecum in E. myurus supports the view that Macroscelididae have evolved from ancestral herbivores and not from insectivores.

On mammalian sperm dimensions.

Data on linear sperm dimensions in mammals are presented. There is information on a total of 284 species, representing 6.2% of all species; 17.2% of all genera and 49.2% of all families have some representation, with quantitative information missing only from the orders Dermoptera, Pholidota, Sirenia and Tubulidentata. In general, sperm size is inverse to body mass (except for the Chiroptera), so that the smallest known spermatozoa are amongst those of artiodactyls and the largest are amongst those of marsupials. Most variations are due to differences in the lengths of midpiece and principal piece, with head lengths relatively uniform throughout the mammals.