Narrowband UVB therapy for vitiligo: does the repigmentation last?

BACKGROUND: Since 1997, a number of trials have shown promising results in treating generalized vitiligo with narrowband ultraviolet B (UVB) both in adults and children. However, there is little knowledge concerning the duration and permanency of the treatment-induced repigmentation. OBJECTIVE: Our main objective was to perform a follow-up trial of successfully treated patients receiving narrowband UVB for generalized vitiligo. METHODS: We have investigated to what degree the treatment-induced repigmentation remains stable for up to 2 years post-treatment. We performed an initial open trial including 31 patients with generalized vitiligo. They received narrowband UVB thrice weekly for up to 12 months. Patients experiencing > 75% repigmentation were defined responders and were included in the follow-up trial. Responders were followed every 6 months for up to 2 years after cessation of treatment. We observed the pigmentation status and registered any changes indicating loss of pigmentation and relapse. RESULTS: Eleven of the 31 treated patients were included in the follow-up trial. Six patients had relapse and five patients had stable response 24 months after cessation of treatment. Four out of six relapses were within 6 months post-treatment. CONCLUSION: In our study population of 31 patients with generalized vitiligo, five patients (16%) experienced > 75% stable repigmentation 2 years after cessation of a treatment programme of up to 1 years narrowband UVB therapy.     

Lead poisoning in precious metals refinery assayers: A failure to notify workers at high risk

Lead poisoning in a precious metals refinery fire assayer and a routine OSHA inspection prompted an investigation of the index facility, a survey of the industry, and efforts to notify assayers of this previously unrecognized hazard. Air and blood samples were obtained at the index facility. Management personnel from all fire assay laboratories in Rhode Island and southern Massachusetts were interviewed. The industry's trade association, OSHA, NIOSH, trade unions, and the media were asked to assist in a nationwide notification effort. Assayers at the index facility had excessive exposures to lead due to an age-old, lead-based assaying method that remains the industry gold standard. Blood lead levels of the three assayers (mean 61.3 μ/dl, range 48–86 μg/dl) were considerably higher than those of 16 other refinery workers (mean 27.4 μg/dl, range 13–49 μg/dl). The industry survey revealed inadequate knowledge of both the lead hazard and the applicability of the OSHA lead standard. Notification efforts failed in large part due to economic obstacles. The notification of workers at high risk of lead exposure and the eradication of occupational lead poisoning will require greater attention to economic forces. © 1994 Wiley-Liss, Inc.     

Spectrophotometric method of quantifying adult cat flea (Siphonaptera: Pulicidae) feces.

Cat flea, Ctenocephalides felis felis (Bouché), feces are an essential part of larval nutrition under natural conditions. The mass values of adult flea feces can be measured by dissolving samples of flea feces in Drabkin's reagent, filtering, centrifuging, and measuring absorbance spectrophotometrically at 540 nm. Either flea feces or air-dried host blood can be used to generate the standard curve used to convert absorbance (optical density) values into mass values. Debris collected from flea-infested house cats averaged 23.02 mg debris per cat per h with an average of 10.41 mg flea feces per cat per h. Flea feces deposited in the environment serve as potential larval food. Adult flea feces comprised an average of 44.28% of the debris deposited from infested domestic house cats in this study.     

Piperacillin-Tazobactam Pharmacokinetics in Patients With Intraabdominal Infections

Study Objective . To determine the appropriate compartmental and noncompartmental pharmacokinetic parameters for intravenous piperacillin and tazobactam. Design . Sequential selection of patients entered into a randomized, open-label clinical efficacy trial. Setting . Los Angeles County-University of Southern California Medical Center. Participants . Sequential sample of 18 patients admitted for intraabdominal infections and consented into a comparative antibiotic trial. Interventions . Patients received piperacillin 4 g plus tazobactam 500 mg by intravenous intermittent infusion every 8 hours. Measurements and Main Results . The estimated noncompartmental pharmacokinetic parameters (mean ± SD) for piperacillin and tazobactam, respectively, were as follows: maximum concentration in plasma 218.7 ± 48.9 μg/ml and 27.8 ± 9.1 μg/ml; half-life 1.07 ± 0.22 hours and 1.00 ± 0.27 hours; elimination rate constant 0.67 ± 0.13 hr⁻¹ and 0.73 ± 0.18 hr⁻¹; area under the concentration-time curve from zero hour to infinity 288.5 ± 71.25 mg·hr/L and 36.3 ± 9.55 mg·hr/L; total plasma clearance 14.75 ± 3.93 L/hour and 14.78 ± 4.39 L/hour; renal clearance 5.69 ± 1.94 L/hour and 7.85 ± 3.37 L/hour; volume of distribution at steady state 21.00 ± 4.18 L and 22.47 ± 8.27 L; and mean residence time 1.72 ± 0.29 hours and 1.79 ± 0.35 hours. Conclusion . Our findings were similar to those in other surgical patient models. The two-compartmental model best described piperacillin and tazobactam disposition in our patients. Bayesian analyses of the two-compartment models of piperacillin and tazobactam were able to predict trough, peak, and 2-hour postadministration levels without bias.     

Fetal lumbar spine: measuring axial growth with US

Ultrasound (US) can be used to visualize vertebral segments, suggesting a quantitative means of studying vertebral column growth in utero and thus a means of detecting developmental abnormalities. US images of the lumbar spine were obtained in 128 clinically normal fetuses between the gestational age of 11 through 41 weeks. A large-aperture, dynamically focused US system capable of regional magnification was used. Average lumbar spacing was calculated from distance between centrums of at least four lumbar bodies. The average distance between lumbar centrums increased nearly linearly throughout the second and third trimesters (r2 = 0.98). Enhanced anatomic display implies new capabilities for recognizing developmental abnormalities antenatally.