Serum- and bradykinin-induced calcium transients in familial Alzheimer's fibroblasts

The calcium-sensitive photoprotein, aequorin, was used to examine serum- and bradykinin-induced transient increases in free cytosolic calcium ions in skin fibroblasts from 10 individuals with early onset familial AD (FAD), including four who were biopsied before their clinical symptoms would allow a diagnosis of AD, 2 individuals with late onset FAD, 8 at-risk but nonsymptomatic individuals, and 13 controls. The data show that (a) among controls, the peaks of the calcium transients increase in height as a function of donor age; (b) transients induced by 10% serum, 10 nM bradykinin (BK) or 100 nM BK were generally lower in FAD fibroblasts, including those from donors in the early stages of the disease, than in age-matched control cells; (c) such transients are reduced in cells from a proportion of the nonsymptomatic, at-risk individuals. Thus, serum- and BK-induced calcium transients are reduced in fibroblasts from both early and more advanced stage FAD donors and perhaps even from donors who are presymptomatic carriers of the defective gene. The data also suggest that changes in calcium transients in FAD fibroblasts neither mimic nor exaggerate the effects of normal aging.     

The diagnostic significance of clinical signs of right ventricular insufficiency in patients with chronic obstructive bronchitis

A parasitologic investigation, realised between March and November 1993, among 532 pupils 6-15 years old living in N'Djamena's peripheric quarter and in 5 Chari Baguirmi's villages had showed urogenital schistosomiasis infection prevalence is 11.8%.     

Basic laparoscopic knowledge among gynecologic laparoscopists

OBJECTIVE: Our purpose was to assess the basic knowledge of laparoscopy and laparoscopic sterilization among gynecologic laparoscopists. STUDY DESIGN: A four-part multiple-choice test designed for use in residency training, covering basic aspects of laparoscopy and laparoscopic sterilization, was distributed to 155 registrants at a gynecologic surgery postgraduate course. Test results were compared among subgroups, as well as with results for 23 residents who had taken the test before their rotation in laparoscopic sterilization. RESULTS: Residents scored higher than practitioners on all test segments. No practitioner achieved the 85% correct passing score required of residents. Practitioner scores did not increase as the number of laparoscopic sterilizations performed per year increased, but higher test scores were associated with more recent completion of residency. CONCLUSION: Basic knowledge of laparoscopic sterilization among practicing gynecologists, as measured by a test designed for residents, is less than that of the residents.     

A community-based public-academic liaison program

OBJECTIVE: The authors discuss obstacles and incentives associated with successful community-based public-academic liaison activities and illustrate their conclusions by describing their public-academic liaison program, which received the American College of Psychiatrists' first annual Award for Creativity in Psychiatric Education. METHOD: The first 8 years of a state/university collaboration are described in which the parties involved first developed a variety of innovative services designed to fill specific gaps in the public service delivery system and subsequently integrated academic research and training components. RESULTS: The carefully planned and monitored process resulted in the exponential growth of interest in public sector work, the realization of the university's primary goals of developing high quality training and research sites, a substantial increase in the number of graduates accepting positions in the public sector, several projects funded by the National Institute of Mental Health, and two national awards. CONCLUSIONS: These collaborations illustrate the highly complementary relationship of public-academic liaison activities and their potential capacity to improve access to services, substantially improve the quality of these services, generate extramural support for services research, and increase the number of well-trained professionals in the public sector.     

Doublet potentiation during eccentric and concentric contractions of cat soleus muscle

The addition of an extra stimulus pulse, or doublet, at the beginning of a low-frequency train has been shown to substantially increase isometric force. This study examined the effects of muscle movement on this doublet potentiation. The soleus muscles of anesthetized cats were stimulated at 10 Hz for 1 s, with and without an added doublet (0.01-s interval). Isovelocity releases reduced but did not eliminate peak and early doublet potentiation (average 0.0-0.5 s after the doublet). Large releases, >0.4 s after the doublet, completely abolished sustained doublet potentiation (average 0.5-1.0 s after the doublet). In contrast, early isovelocity stretches boosted peak doublet potentiation. Yet, large stretches later in the stimulus almost completely eliminated sustained doublet potentiation. This suggests that a different mechanism is responsible for early and sustained doublet potentiations. Because peak and average initial doublet potentiation were not strongly affected by movement, doublets still offer a viable control strategy to increase force during movement while minimizing the number of stimulus pulses.     

In vitro cultivation of Wolbachia pipientis in an Aedes albopictus cell line

Bet v 1, the single major allergen from birch pollen, shares IgE epitopes with all major tree pollen allergens from closely related species such as alder, hazel, hornbeam, beech, and European chestnut. Because of high sequence homologies among these allergens and the well-studied cross-reactivities on B cell epitopes, Bet v 1 is a representative model protein which can be used for in vitro studies. The cDNA coding for Bet v 1, the single major allergen from birch pollen, was cloned into the T7-based Escherichia coli expression system pMW 175/BL21(DE3) and synthesized as a nonfusion protein. In contrast to other E. coli systems (e.g., pKK233-2/JM105), this system produces high levels of readily extractable proteins corresponding to 5-10% of E. coli total protein, the percentage varying with culture conditions. The overall yield was 8-10 mg of purified recombinant protein per liter of culture medium. The recombinant allergen was purified by several steps, including ion-exchange and hydrophobic interaction chromatography. The purified recombinant allergen showed identical immunological properties with the respective natural counterpart. The use of recombinant allergens of high purity is expected to result in more accurate diagnostic procedures, but possibly also in a superior immunotherapy of Type I allergic diseases when compared with methods using crude allergen extracts containing various amounts of allergen concentrations.     

Effect of lipectomy on growth and development of hyperinsulinemia and hyperlipidemia in the Zucker rat

The Zucker fat rat inherits obesity and hyperinsulinemia, exhibits insulin resistance, and is, therefore, a model of adult onset, or type II, diabetes. The purpose of this study was to determine if excision of fat depots from the infant Zucker (fa+/fa+) rat would affect growth, fat cell number, hyperinsulinism, and hyperlipidemia. In the experimental design, 10 percent of the total body weight (inguinal and interscapular depots) was excised at 6 weeks of age from 18 fat and 18 lean (fa+/fa-) litter mates, with 18 fat and 18 lean rats serving as nonoperated controls. At intervals, serum glucose, insulin, cholesterol, and triglycerides were measured. Initially, the operated fat group was significantly (p < 0.01) lighter than the nonoperated group. By 9 weeks postoperatively, the operated fat rat group had regained weight and continued to grow at the same rate as the nonoperated fat rats because of intra-abdominal fat depots. Lipectomy had no effect on growth rate of the lean rat group. Although lipectomy caused no consistent change in serum glucose or insulin levels, it caused a significant decrease in lipid levels. For example, the operated fat rats had a reduction in cholesterol from 876 to 171 mg/dl by 15 weeks postoperatively, and serum cholesterol persisted at about 50 percent of the nonoperated group throughout the rest of the study (38 weeks postoperatively). Even a greater reduction in triglyceride levels occurred, for example, from 7415 to 1082 mg/dl at 24 weeks postoperatively. Lipectomy did not cause a change in lipid levels in the lean group. It is concluded that the lipectomy in the Zucker fat group is an excellent model to evaluate the effects of changes in fat cell number on lipid metabolism.     

Detection of extended-spectrum beta-lactamases. The reliability of methods for susceptibility testing as used in Denmark

The susceptibility testing methods used in Denmark were evaluated with respect to their ability to detect cephalosporin resistance with cefuroxime as indicator, especially resistance caused by extended-spectrum beta-lactamases (ESBLs). Two methods for determination of minimal inhibitory concentration (MIC), three agar diffusion methods, a disc approximation test and the ESBL-Etest were used against a panel of strains producing well-known beta-lactamases. The tablet diffusion test (Rosco Neo Sensitabs) as the most used in Denmark had the lowest detection rate of cefuroxime resistance among ESBL-producing strains. The prediffusion method, which is only used at one laboratory, was the most reliable method for such detection. The MIC methods were in good agreement, but the detection rate for resistance due to ESBLs was low and depended on the antibiotics used. The disc approximation test and the ESBL-Etest both resulted in an acceptable ESBL detection rate. The latter tests discriminated between isolates producing the frequent chromosome-mediated and the in Denmark probably very rare ESBL-mediated cephalosporin resistance. For the evaluation of susceptibility tests such strains require special attention.     

Effects of variability of practice in a movement-education program on motor skill performance

The study investigated the effects of the direct and exploration methods of teaching on the overhand throwing performance of kindergarten children. Variable throwing practice was provided in the exploration method by allowing children to throw 5 different types of balls at a variety of targets. Children given the direct method threw only one type of ball and received specific instruction and demonstrations. Throwing for distance and throwing accuracy were measured on pre- and posttests. A novel throwing task was administered on the posttest to measure skill transfer. The experimental groups received instruction three times per week for 4 wk. in throwing while a control group received no instruction. Significant sex differences in throws were found for distance and accuracy. Analysis of data from the novel task gave no significant effects. The two methods of teaching did not produce different levels of throwing skill.