Testosterone positively regulates vagina NO-induced relaxation: an experimental study in rats.

PURPOSE: Female sexual response involves a complex interplay between neurophysiological mechanisms and the nitric oxide (NO)-mediated relaxation of clitoris and vagina. The aim of this study was to evaluate sex steroids regulation of the relaxant pathway in vagina, using a validated animal model. METHODS: Subgroups of OVX Sprague-Dawley rats were treated with 17ß-estradiol, testosterone, or testosterone and letrozole, and compared with a group of intact animals. Masson's trichrome staining was performed for morphological evaluation of the distal vaginal wall, in vitro contractility studies investigated the effect of OVX and in vivo treatments on vaginal smooth muscle activity. RNA from vaginal tissue was analyzed by semi-quantitative RT-PCR. RESULTS: Immunohistochemical analysis showed that OVX induced epithelial and smooth muscle structural atrophy, testosterone and testo + letrozole increased the muscle bundles content and organization without affecting the epithelium while 17ß-estradiol mediated the opposite effects. In vitro contractility studies were performed on noradrenaline pre-contracted vaginal strips from each experimental group. Acetylcholine (0.001-10 µM) stimulation induced a concentration-dependent relaxation, significantly reduced by NO-synthase inhibitor L-NAME and by guanylate cyclase inhibitor ODQ. OVX resulted in a decreased responsiveness to acetylcholine, restored by testosterone, with or without letrozole, but not by 17ß-estradiol. OVX sensitivity to the NO-donor SNP was higher than in the control. Vardenafil, a PDE5 inhibitor, enhanced SNP effect in OVX + testosterone as well as in control, as supported by RNA expression analysis. CONCLUSIONS: Our study demonstrates that testosterone improves the NO-mediated smooth muscle vaginal cells relaxation confirming its role in maintaining the integrity of muscular relaxant machinery.

Functional living skills assessment: a standardized measure of high-order activities of daily living in patients with dementia.

AIM: Performance measures are tools aimed to directly evaluate social function in older adults. The authors present the standardization of a new direct performance measure for patients with dementia, the functional living skills assessment (FLSA). METHODS: FLSA was conceived to detect functional impairment in very mild to moderate patients and to pick up functional modification due to intervention. The patient is asked to perform an activity, and the performance is scored according to completeness and level of assistance required. Eight areas of interest are evaluated (Resources, Consumer Skills, Public Transportation, Time Management, Money management, Leisure, Telephone Skills, Self-Care and Health). Subjects included 54 patients with dementia and 36 normal controls. RESULTS: Total and partial FLSA scores significantly differed for the two groups (P<0.0001). Performance on FLSA could divide clinical dementia rating (CDR) 0 from CDR 1, CDR 2 e CDR 3 groups. Both sensitivity and specificity were 94%; inter-rater and test-retest reliability was good (P>0.9). Correction scores for education were calculated, while age influence was only marginally significant. Mini Mental State Examination (MMSE) and CDR highly influenced FLSA score (P< 0.0001); FLSA was highly correlated with another performance measure (the Direct Assessment of Functional Status; P=0.821), and with the Instrumental Activity of Daily Living (IADL) scale (P=-0.612), while no significant correlation was present with the Geriatric Depression Scale. CONCLUSION: FLSA evidences construct, concurrent and discriminative validity. We suggest that this tool could be possibly useful when a high sensibility to different levels of functional impairment is needed, as evaluation of treatment efficacy (both non-pharmacological and pharmacological) identification of relatively intact functional areas to plan cognitive rehabilitation, and confirmation of dementia in the initial phase when there are doubts about functional decline.

Liquid chromatography tandem mass spectrometric quantitation of sulfamethazine and its metabolites: direct analysis of swine urine by triple quadrupole and by ion trap mass spectrometry.

This work describes a new method for the quantitation of trace amounts of sulfamethazine (SMZ) and its main metabolite, N4-acetylsulfamethazine (Ac-SMZ), in swine urine, using high-performance liquid chromatography (HPLC) tandem mass spectrometric analysis of crude urine after addition of internal standard and simple dilution with water. The aim was to determine whether residues of this sulfamidic drug, normally administered to swine in order to prevent infectious diseases, were present in urine at levels lower than those permitted by regulatory authorities before human consumption (EU Project SMT, contract number CT 96-2092). A 10 microL volume of diluted urine was injected into a very short, narrow-bore chromatographic column (Zorbax SB-C18 2.1 i. d. x30 mm length, 3.5 microm pore size). Elution of the analytes of interest was achieved in less than seven minutes using a rapid gradient (from 20 to 80% methanol in 3 minutes). Either a PE Sciex API 365 triple quadrupole (QqQ), operated in the selected reaction monitoring (SRM) mode, or a Finnigan LCQ ion trap (IT) mass spectrometer, operated in narrow-range product ion scan, was used as the final detector. Electrospray (ESI) was used as the ionization technique. A comparison of the two tandem mass spectrometers was performed by analyzing the same set of test samples, at three concentration levels, on three different days. Linearity of responses of the calibration standards, intra- and inter-assay precision of the samples, specificity and limits of detection were evaluated for both systems. Both the QqQ and the IT instrument was suitable for rapid, sensitive and specific determination of the analytes, although the overall performance of the QqQ was slightly superior in terms of linearity, precision and sensitivity.