Revascularization of calvarial, mandibular, tibial, and iliac bone grafts in rats

The development of approaches to screening of hospital patients for harmful drinking frequently encounters resistance from both patients and hospital staff. A contributing factor could be the discomfort both feel about talking specifically about drinking. One approach to reducing this discomfort has been to mask concern about alcohol consumption into a general focus on other health and lifestyle issues. One-hundred and eighty-two patients admitted to an emergency department were presented randomly with either a straight alcohol screening questionnaire or a general health and lifestyle questionnaire with alcohol questions embedded amongst items on smoking exercise and diet. The number of returns was equal for both questionnaires which suggests the masked questionnaire does not improve the acceptability of alcohol screening in hospital environments.     

Analyzing the performance of a cluster-based architecture for immersive visualization systems

Cluster computing has become an essential issue for designing immersive visualization systems. This paradigm employs scalable clusters of commodity computers with much lower costs than would be possible with the high-end, shared memory computers that have been traditionally used for virtual reality purposes. This change in the design of virtual reality systems has caused some development environments oriented toward shared memory computing to require modifications to their internal architectures in order to support cluster computing. This is the case of VR Juggler, which is considered one of the most important virtual reality application development frameworks based on open source code.     

Derivation of a clinical decision rule for whiplash associated disorders among individuals involved in rear-end collisions

A prospective study was used to: (1) quantify potential risk factors for whiplash associated disorder following a rear-end motor vehicle collision; and (2) develop a simple clinical decision rule for the early identification of patients at risk for long-term whiplash associated disorder. Between 1 October 1995 and 31 March 1998, 446 adults involved in rear-end collisions presented to the only two emergency departments serving Kingston, Ontario. Eligible and consenting subjects (n = 353) were contacted by telephone soon after the collisions then at multiple occasions up to 2 years post-collision. Bivariate and multiple logistic regression analyses were used to identify potential risk factors for persistent symptoms. A software package that uses Chi-squared automatic interaction detection and classification and regression trees was used to develop a simple clinical decision rule for the identification of patients at high and low risk for persistent whiplash associated disorder. Risk factors identified by regression analyses included: increased age, number of initial physical symptoms, and early development of the following symptoms: upper back pain, upper extremity numbness or weakness, or disturbances in vision. A simple clinical decision rule that requires asking up to three basic questions of each patient was derived and would have identified the 118 cases of persistent whiplash associated disorder with a sensitivity of 91.5% (95% confidence interval: 86.5, 96.6) and a specificity of 51.4% (44.7, 58.1). This study confirmed the importance of several risk factors for whiplash associated disorder following rear-end motor vehicle collisions.     

Aryl phosphate derivatives of bromo-methoxy-azidothymidine are dual-function spermicides with potent anti-human immunodeficiency virus

Detergent-based vaginal microbicides, in addition to their high contraceptive failure rates, cause mucosal erosion and local inflammation that might increase the risk of heterosexual human immunodeficiency virus (HIV) transmission. In a systematic effort to identify a microbicide contraceptive potentially capable of preventing the sexual transmission of HIV as well as providing fertility control, a series of novel aryl phosphate derivatives of 5-bromo-6-methoxy-3'-azido-3'-deoxythymidine (AZT; zidovudine) were synthesized and examined for dual anti-HIV and sperm-immobilizing activity (SIA). Whereas AZT displayed potent anti-HIV activity (IC50 = 0.006 microM) but lacked SIA (EC50 > 300 microM), two 5-bromo-6-methoxy-aryl phosphate derivatives of AZT, compounds WHI-05 and WHI-07, exhibited potent anti-HIV activity as well as SIA. The IC50 (HIV) and EC50 (SIA) values for WHI-07 were 439-fold and 13.5-fold lower, respectively, than those for the detergent-based virucidal spermicide, nonoxynol-9 (N-9). Sperm motion kinematics using computer-assisted sperm motion analysis combined with confocal laser scanning microscopy, high-resolution low-voltage scanning, and transmission electron microscopy demonstrated that both WHI-05 and WHI-07 cause a complete and irreversible loss of sperm motility in a concentration- and time-dependent fashion without concomitantly affecting the sperm acrosomal membrane integrity. In experiments designed to assess the fertilizing capacity of treated sperm, preincubation of sperm with either compound resulted in a concentration-dependent loss of the ability to adhere to and penetrate zona-free hamster eggs as well as inhibition of binding to human zona. WHI-07 applied intravaginally prior to artificial insemination of epididymal sperm drastically reduced fertility in hormonally primed CD-1 mice. Unlike the intravaginal application of N-9, repetitive intravaginal application of WHI-07 did not damage the vaginal epithelium or cause local inflammation. Structure-function relationship analyses showed that the addition of bromo-methoxy functional groups to AZT was essential for, and the aryl phosphate derivatization contributory to, the SIA of both compounds. Compounds WHI-05 and WHI-07 may be useful as dual-function vaginal contraceptives for women who are at high risk for acquiring HIV/acquired immunodeficiency virus syndrome by heterosexual vaginal transmission.     

Blood and plasma selenium levels and GSH-Px activities in patients with arterial hypertension and chronic heart disease

Among the 57 monoclonal antibodies analyzed within the T-cell group of the Second International Swine CD Workshop, one mAb fell within cluster T14a that included the CD6 standard a38b2 (No. 175). The new mAb MIL8 (No. 082) and a38b2 both precipitated from activated T-cells a 150 kDa monomeric protein. Staining patterns on the various cell types were similar. There was no inhibition of binding of either mAb to peripheral blood T-cells with the opposite mAb. The new mAb, MIL8, reacts with a separate epitope on porcine wCD6.     

Factors which affect the relative contributions of ovarian and uterine arteries to the blood supply of reproductive organs in guinea pigs

The establishment and stability of the behavioral baseline for rats in relation to the schedule of differential reinforcement of low rate under water reinforcer (DRL 20 sec for water) were studied, with the following results: When the DRL value was gradually stepped up from 1 sec to 20 sec with the advance of the sessions from 1to 16, the establishment of the behavioral baseline was slower than when DRL 20 sec was applied from the start. The establishment of the baseline was clearly accelerated by the prolongation of the length of time for training in one session from 60 min to 120 min. The baseline remained highly stable without being affected by the intermittent administration (2-3 times a week) of methamphetamine and diazepam, each in doses from 0.06 to 1.0 mg/kg, and of caffeine and pentobarbital, each in doses from 1.2 to 20 mg/kg, or by the discontinuation of the test from 1 to 15 days. However, during the retraining period following the test discontinuation it was found that the baseline fluctuated for a long time due to the elimination of water deprivation. The baseline stability, once established, could be maintained through about 300 daily sessions, with only a slight dependence on the change in environmental conditions such as humidity, temperature, and the season.     

Transgenic animal models: new avenues in cardiovascular physiology

Coryneform bacteria and yeasts of 21 brick cheeses from six German dairies, produced by using undefined ripening cultures, were identified. Arthrobacter nicotianae, Brevibacterium linens, Corynebacterium ammoniagenes, Corynebacterium variabilis and Rhodococcus fascians were found in significant numbers. Out of 148 coryneform isolates 36 could not be identified at the species level. With the exception of a large rennet cheese, the coryneform microflora of rennet and acid cured cheeses were similar, but the cheeses had clearly different yeast populations. Debaryomyces hansenii and Galactomyces geotrichum prevailed in rennet cheeses while Kluyveromyces marxianus and Pichia membranaefaciens were the main species found in acid cured cheese. The dominance of Yarrowia lipolytica probably indicates an improper yeast population, resulting in poor cheese quality. Some of the species identified are potential candidates for designing a defined ripening culture for rennet red smear cheese.