Optimising growth conditions for the pectinolytic activity of Kluyveromyces wickerhamii by using response surface methodology.

This present study was undertaken to find optimum conditions of pH, temperature and, period of incubation for the pectinolytic activity of Kluyveromyces wickerhamii isolated from rotting fruits and to assess the effect of these factors by use of response surface methodology (RSM). A central composite rotatable design was used as an experimental design for the analysis of the allocation of treatment combinations. A second order polynomial regression model was fitted and was found adequate, with an R(2) of 0.94469 (P<0.001). The effects of temperature and pH were the most significant factors in influencing enzyme production. Estimated optimum conditions were as follows: pH 5.0, temperature, 32 degrees C and an incubation period of 91 h. Pectinesterase (PE), pectin lyase (PL), and cellulase activities were not detected. Pectinase production was partially constitutive. Pectin was degraded by the isolated strain of K. wickerhamii in the current study, and the pectinolytic activity is referred to as polygalacturonase (PG) activity. Crude enzyme extract was thermostable at various temperatures and, stimulated by the presence of Ca(2+) ions but inhibited by other ions like Mg(2+), Zn(2+), Co(2+), Mn(2+) and Na(+).

Emergency department workplace interruptions: are emergency physicians "interrupt-driven" and "multitasking"?

OBJECTIVE: Although interruptions have been shown in aviation and other work settings to result in error with serious and sometimes fatal consequences, little is known about interruptions in the emergency department (ED). The authors conducted an observational, time-motion task-analysis study to determine the number and types of interruptions in the ED. METHODS: Emergency physicians were observed in three EDs located in an urban teaching hospital, a suburban private teaching hospital, and a rural community hospital. A single investigator followed emergency staff physicians for 180-minute periods and recorded tasks, interruptions, and breaks-intask. An "interruption" was defined as any event that briefly required the attention of the subject but did not result in switching to a new task. A "break-intask" was defined as an event that required the attention of the physician for more than 10 seconds and subsequently resulted in changing tasks. RESULTS: The mean (+/-SD) total number of patients seen at all three sites during the 180-minute study period was 12.1 +/- 3.7 patients (range 5-20). Physicians performed a mean of 67.6 +/- 15.7 tasks per study period. The mean number of interruptions per 180-minute study period was 30.9 +/- 9.7 and the mean number of breaks-in-task was 20.7 +/- 6.3. Both the number of interruptions (r = 0.63; p < 0.001) and the number of breaks-in-task (r = 0.56; p < 0.001) per observation period were positively correlated with the average number of patients simultaneously managed. CONCLUSIONS: Emergency physicians are "interruptdriven." Emergency physicians are frequently interrupted and many interruptions result in breaks-in-task.

Studies on production, physiochemical and sensory properties of a standard kilishi ingredient mix powder.

The quality of kilishi, a sun dried roasted meat product vary considerably due to lack of consistent standardized non meat ingredient portion (spices and condiments) used for its preparation. In this study, an instant standard kilishi ingredient mix powder was developed. The mix powder contained 9.1% moisture, 49.7% protein, 8.3% fat, 3.2% fibre, and 4.4% ash. Particle size of the mix developed was finer than the traditional one. Yield of kilishi increased with increasing concentration of the standard mix powder used for infusion. The highest yield (87%) was obtained at 60% slurry concentration of the mix compared to 59% yield when the traditional paste was used for infusion. Sensory attributes of kilishi produced using 60% slurry concentration of the standard mix was rated better than a commercial kilishi product (P < 0.05).

Shigella and Salmonella strains isolated from children under 5 years in Gaborone, Botswana, and their antibiotic susceptibility patterns.

We isolated Shigella from 43/221 (21%) and Salmonella 8/221 (3%) rectal swabs from children under 5 years with diarrhoea, and found Shigella in two of 100 specimens from children without diarrhoea. Sh. boydii (13%) was the most prevalent Shigella species followed by Sh. flexneri (6%) and Sh. sonnei (2%). The prevalence of various types of Sh. boydii was type 7, 5%; type 9, 3%; type 12 and 16, 2%; and type 18, 1%. Other Shigella serotypes encountered were Sh. flexneri type 6 (4%), type 4 (2%), with Sh. sonnei phase II isolated from 2% of the specimens. The Salmonella species were S. typhimurium and S. paratyphi. The high rate of isolation of Shigella species from children with diarrhoea is indicative of a definite role of this enteropathogen in causing endemic diarrhoea in Gaborone, Botswana. Antibiograms of the predominant isolates showed that most Shigella species were resistant to ampicillin but susceptible to chloramphenicol, and with the exception of Sh. flexneri type 6, also susceptible to gentamicin. The Salmonella species were susceptible to chloramphenicol, collistin-sulphate, gentamicin, cotrimoxazole, and ampicillin.

Impact of pharmacy-based syringe access on injection practices among injecting drug users in Minnesota, 1998 to 1999.

In Minnesota, state legislation, enacted July 1998, provided for voluntary pharmacy sales of syringes/needles without a prescription for an accompanying drug. The goal was to stem HIV transmission among injecting drug users (IDUs) by providing greater access to sterile syringes. We used a pre/post evaluation design to investigate the impact of less restrictive syringe/possession laws on IDUs' HIV-related syringe practices. Independent cross-sectional samples of IDUs were recruited from street sites and a correctional facility immediately before and 1 year after enactment of the laws. Of the 671 IDUs interviewed, 570 (270 prelegislation and 300 postlegislation) had injected at least once in the 30 days before the interview. IDUs were more likely to purchase syringes at pharmacies after enactment of the laws (odds ratio [OR], 2.66; 95% confidence interval [CI], 1.83-3.85), yet did not change their behaviors regarding carrying unused syringes (OR, 0.90; 95% CI, 0.63-1.28). After adjusting for speedball injection and criminal history, syringe sharing decreased among IDUs (adjusted OR, 0.67; 95% CI, 0.45-1.00) yet syringe reuse remained the same (adjusted OR, 0.67; 95% CI, 0.40-1.11). Safe disposal of syringes did not differ significantly across the sampling periods (adjusted OR, 1.32; 95% CI, 0.84-2.06). Increased access to pharmacy syringes offers a first step at reducing HIV-related syringe practices but must be coupled with strong HIV prevention messages, drug treatment referrals, and safe syringe disposal options.