[Osteoporosis prevalence in open population at Mexico City]. / Prevalencia de osteoporosis en población abierta de la Ciudad de México.

BACKGROUND: In Mexico there isn't accurate epidemiologic information of osteoporosis prevalence, however it is estimated that 24.5 million people are at risk or suffer it yet. OBJECTIVE: To show prevalence of osteoporosis in open population of several areas of Mexico City. PATIENTS AND METHOD: Retrospective, transversal and open study at an osseous densitometric data base information from 5,924 patients. RESULTS: Densitometry evidence that 17.9% suffer osteoporosis (79.8 female and 20.1% male), 34.5% osteopeny (76.1 female and 23.8 female), and 47.4% had normal bones (75.8% female and 24.1% female). CONCLUSIONS: Since osseous mineral density changes exponentially increases with age, osteopenic and osteoporosis index is very high after 40 years old; due to that there must be considered preventative programs for young groups, and to practice densitometries to 30 year old men and women.

Bioequivalence of two commercial preparations of trimethoprim/sulfamethoxazole: a randomized, single-dose, single-blind, crossover trial.

BACKGROUND: Trimethoprim/sulfamethoxazole (TMP/SMX) is a combination of 2 antimicrobial agents that act synergistically, sequentially blocking 2 chemical reactions essential to bacterial survival. TMP/SMX is effective against organisms that are resistant to its separate components. OBJECTIVE: The objective of this study was to compare the bioavailability of 2 commercial preparations of T:MP/SMX 40/200 mg per 5-ml, oral suspension, used in Mexico for the treatment of bacterial infection. METHODS: This study used a single-dose, randomized,single-blind, 2 x 2 crossover (2 dosing periods x 2 treatments) design to compare the 2 preparations. Healthy male volunteers aged 18 to 55 years received the trial and reference preparations in randomized sequence, under fasting conditions, with a 7-day washout period between dosing periods. Each preparation was administered as a single-dose 10-ml, oral suspension delivering 80 tng of TMP and 400 mg of SMX (equivalent to 2 doses of TMP/SMX 40/200 rig per 5 ml.). Pharmacokinetic (PK) parameters of C(max) AUC(0-t), and AUC(0-1) were determined for each component of each preparation. Schuirmann's unilateral double t test was performed. Null hypotheses indicating bioin-equivalence (P > 0.05) were rejected. Bioequivalence was determined if the quotient of the parameters of C(max), AUC(0-t), and AUC(0-infinity) were between 80% and 125%, at a power of 80% (alpha > 0.08). RESULT: Twenty-three of the 24 enrolled subjects completed the study. The subjects were all Hispanic, the mean (SD) age was 25 (6) years, and the mean (SD) body mass index was 22.54 (2.59) kg/m(2). Plasma concentration-time values of TMP and SMX were similar with both preparations. The null hypotheses of Schuirmann's unilateral double t test were rejected, and results of the analyses of the PK parameters obtained 95% CIs within the predetermined range of bioequivalence (80%-125 degrees 10). The trial and reference preparations were statistically interchangeable and appeared to be bioequivalent. CONCLUSIONS: Based on similar PK profiles and statistical analyses, the trial and reference preparations were statistically interchangeable and appeared to be bioequivalent in this population of 23 healthy male volunteers in Mexico.