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Cumulative Time (cumulative + time)
Selected AbstractsIntermittent exposure to low-concentration paraphenylenediamine can be equivalent to single, higher-dose exposureCONTACT DERMATITIS, Issue 5 2007Jonathan M. L. White Hair dye allergy is an important and increasingly common cause of allergic contact dermatitis. The role of repeated exposure in elicitation of allergy has not previously been extensively studied. We have therefore compared elicitation between single and intermittent exposure to paraphenylenediamine (PPD). 23 subjects known to be allergic to PPD from positive patch tests were exposed to 0.3% and 0.03% PPD, both in petrolatum and water, for 5 min at the same site every day for up to 8 D. In the same subjects, single exposures were also performed at different sites, from 5 to 40 min. Other experiments exposed rat skin to radiolabelled PPD as one-off application or multiple exposures. There were 8 reactions in the cumulative exposure site using 0.3% PPD in aqueous solution. In 7 of these, there was an exact correlation with reaction to the cumulative time needed for repeat exposures to elicit a reaction and the time needed for a reaction to the single exposure. There were no reactions to 0.03% PPD in water or pet under either type of exposure condition. There was also a positive correlation between grade of original reaction in clinic (+++, ++, +) and appearance/intensity of elicitation reactions. In the animal study, cumulative time and single exposure time sites correlated with regards to retention of radiolabelled substance within the skin. This study therefore demonstrates for the first time that, over the time period tested, the allergenic component of PPD accumulates in the skin. Hence, intermittent exposure to lower concentrations of PPD may be equivalent to higher concentration, one-off exposure. [source] Intensity of drug injection as a determinant of sustained injection cessation among chronic drug users: the interface with social factors and service utilizationADDICTION, Issue 6 2004Julie Bruneau ABSTRACT Aims The objective of this study was to identify factors associated with sustained injection cessation and to examine further the relationship between the occurrence of sustained injection cessation of injection drug users (IDUs) and prior injection frequency. Design and setting IDUs in the Montreal St Luc Cohort who had at least three consecutive interviews between 1995 and 1999 were included. Sustained injection cessation was defined as a period of at least 7 consecutive months without injection. All IDUs completed interview-administered questionnaires on socio-demographic characteristics, drug and sexual behaviours and health-related issues. Logistic regression was used for analyses. Findings A total of 186/1004 (18.5%) IDUs reported a period of sustained injection cessation during the study period. In multivariate analysis, HIV-positive status, ,booting' and cumulative time spent in prison were negatively associated with injection cessation, while injection initiation after 35 years of age and frequent crack use were positively associated with injection cessation. We found a negative association between the occurrence of injection cessation and the frequency of injection; the odds ratios (OR) for cessation were 0.49 [95% confidence interval (CI): 0.03, 0.78] for IDUs who injected 30,100 times and 0.21 (95% CI: 0.10, 0.46) for IDUs who injected more than 100 times in the previous month. Attending needle exchange programmes (NEPs) or pharmacies appeared to be a modifier of the relation between cessation and prior injection frequency. The OR was 0.68 (95% CI: 0.42, 1.12) for IDUs who injected 30,100 times prior to injection and attended NEPs or pharmacies and was 0.07 (0.01, 0.30) for IDUs who did not use these services. Conclusions Overall, a fifth of IDUs experienced at least one episode of injection cessation of 7 months or more during a period of 4.5 years. Our data suggest that NEPs and pharmacies may have played a role in inducing injection cessation episodes in a subgroup of IDUs. Research is needed to better identify the characteristics of IDUs who could benefit from an injection cessation intervention strategy. This information is important for social and health policy planning. [source] Impact and Prevention of Far-Field Sensing in Fallback Mode SwitchesPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p2 2003PIERRE BORDACHER BORDACHAR, P., et al.: Impact and Prevention of Far-Field Sensing in Fallback Mode Switches.Far-field oversensing (FFOS) promoted by high atrial sensitivity and short atrial refractory periods induces false positive mode switches. We evaluated the incidence of ventricular FFOS in a population of DDD paced patients. Methods: One hundred thirty-seven patients (71 ± 10years, 76 men) implanted with a Talent DR pacemaker were studied. Before discharge, an analysis of internal data stored in the memories of the PM was performed by the specific software incorporated in the programmer in parallel with a 24-hour Holter recording. Data were validated by a panel of experts. One and 4 months follow-up was based only on the data stored in the PM memories. Results: Pacing indications were atrioventricular block(n = 75), sinus node dysfunction(n = 57), and other(n = 5). Sustained far-field oversensing was observed in 12/137 patients (9%). Out of a total of 3,511 triggered mode switch episodes, FFOS accounted for 20% and 7% of a 311 days cumulative time in mode switch. Inappropriate mode switch episodes induced by far-field were more numerous but shorter than episodes prompted by atrial arrhythmias. Atrial sensitivity was increased in eight patients, successfully in four. Reprogramming of the atrial refractory period(156 ± 11 ms)was successful in five of six patients. Conclusions: A 9% rate of ventricular FFOS was observed in an unselected population, easily and automatically diagnosed using the internal memory function and the automatic analysis provided by the programmer. Prolongation of the atrial refractory period was more effective than resetting of the atrial sensitivity in eliminating FFOS. (PACE 2003; 26[Pt. II]:206,209) [source] Therapeutic efficacy of topical hydrocortisone aceponate in experimental flea-allergy dermatitis in dogsAUSTRALIAN VETERINARY JOURNAL, Issue 7 2009S Bonneau Objective To evaluate the treatment efficacy of a topical spray containing hydrocortisone aceponate (HCA) on dogs with flea-allergy dermatitis (FAD). Design A controlled clinical study was conducted on dogs with experimentally induced FAD. Sixteen laboratory beagles with mild to moderate clinical signs were divided into two groups. The test group received HCA by topical spray once daily for 7 days, while the control group did not. Pruritic events (time and frequency) were videotaped and then scored. Clinical signs (erythema, papules, excoriation and alopecia) present on four anatomical regions were monitored and their severity directly assessed. Results After 2 days, pruritus was reduced by 94% in the treatment group and by 24% in the control group (P = 0.014) in cumulative time, and by 86% versus 34% (P = 0.034) in frequency. The HCA spray also resulted in significant improvements in overall clinical signs: 23% versus 0% in the control group (P = 0.0006) on day 3 and 43% versus 15% in the control group (P = 0.0006) on day 7. During the 7-day trial, no drug-related adverse effects were observed. Conclusions Topical treatment with HCA showed a rapid and potent antipruritic effect on dogs with FAD. HCA also demonstrated significant overall therapeutic effects on FAD-associated skin lesions. [source] | ||||||||||