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111.
BackgroundThe control of blood-borne infections including HIV and hepatitis C (HCV) amongst injecting drug users (IDUs) is a challenge for health authorities in Iran. Hence, more reliable estimates of the levels of blood-borne infections and their associated factors are critically needed.MethodsActive IDUs were recruited using peer-driven sampling in a bio-behavioural survey in 2008. Over 8 weeks, data were collected from adults living in a city in Isfahan Province who had injected drugs in the past month. Participants provided a whole blood sample and answered questions on sexual and drug-related risk characteristics. Participants were provided post-test counselling and a non-monetary incentive for their participation. Excluding two inactive cases, the initial recruits resulted in 2–8 waves of recruitment.ResultsOverall, 118 IDUs including three females participated. The estimated population proportions of HIV, hepatitis B, and HCV infections were 0.7% (95% CI, 0.6–2.3), 0.7% (95% CI, 0.1–2.1), and 59.4% (95% CI, 47.4–68.7), respectively. Responses indicated that 31% (95% CI, 20–44.5) of the IDUs ever shared a needle/syringe for drug injection, and 77% (95% CI, 65–84) had ever injected an addictive solution marketed widely as Temgesic. Multivariate analyses revealed that the high prevalence of HCV infection amongst IDUs is associated with the lifetime duration of drug injection (AOR, 1.17; 95% CI, 1.01–1.34) and with having injected Temgesic (AOR, 4.73; 95% CI, 1.52–14.69).ConclusionOur experience in Iran indicates that IDUs can be recruited effectively in a bio-behavioural survey through peer-driven sampling and using only a single primary incentive. The high prevalence of HCV associated with injecting Temgesic is important evidence for harm-reduction policies in Iran.  相似文献   
112.
Modulation of GTPase and adenylate cyclase (ATP pyrophosphate-lyase, EC 4.6.1.1) activity by Alzheimer's disease related amyloid beta-peptide, A beta (1-42), and its shorter fragments, A beta (12-28), A beta (25-35), were studied in isolated membranes from rat ventral hippocampus and frontal cortex. In both tissues, the activity of GTPase and adenylate cyclase was upregulated by A beta (25-35), whereas A beta (12-28) did not have any significant effect on the GTPase activity and only weakly influenced adenylate cyclase. A beta (1-42), similar to A beta (25-35), stimulated the GTPase activity in both tissues and adenylate cyclase activity in ventral hippocampal membranes. Surprisingly, A beta (1-42) did not have a significant effect on adenylate cyclase activity in the cortical membranes. At high concentrations of A beta (25-35) and A beta (1-42), decreased or no activation of adenylate cyclase was observed. The activation of GTPase at high concentrations of A beta (25-35) was pertussis toxin sensitive, suggesting that this effect is mediated by Gi/G(o) proteins. Addition of glutathione and N-acetyl-L-cysteine, two well-known antioxidants, at 1.5 and 0.5 mM, respectively, decreased A beta (25-35) stimulated adenylate cyclase activity in both tissues. Lys-A beta (16-20), a hexapeptide shown previously to bind to the same sequence in A beta-peptide, and prevent fibril formation, decreased stimulation of adenylate cyclase activity by A beta (25-35), however, NMR diffusion measurements with the two peptides showed that this effect was not due to interactions between the two and that A beta (25-35) was active in a monomeric form. Our data strongly suggest that A beta and its fragments may affect G-protein coupled signal transduction systems, although the mechanism of this interaction is not fully understood.  相似文献   
113.
HIV infection rates have reached epidemic proportions amongst injecting drug users (IDUs) in Iran. Although a number of community-based interventions have being implemented in the country, there is little information on the risk behaviors of IDU participants in these programs. This cross-sectional report aimed to compare the risk behaviors of injecting drug users with differential exposure rates to an HIV outreach program in Tehran, Iran. Results indicated that shared use of needle/syringe in the past month was significantly lower among IDUs who received estimated ≥ 7 syringes per week than those who did not [adjusted odds ratio (OR) = 14.36, 95% confidence interval (CI) 2.30–89.56]. While the effectiveness of this outreach program needs further evaluation through a longitudinal investigation, our preliminary findings suggest that the outreach program in Tehran may have been beneficial in reducing direct sharing among those who received more than several needles/syringes from the program.  相似文献   
114.
OBJECTIVE: To describe 3 new malformations and propose a new subclass of malformations, nonisthmic communicating uteri. STUDY DESIGN: Review of 17,511 hysterosalpingograms revealed 19 cases of communicating uteri. Three cases were identified that showed nonisthmic communications, previously unreported. RESULTS: The 3 new types of communicating uteri were (1) bicornuate uterus with 2 sites of communication, midcervical and isthmic; (2) septate uterus with a midcorporeal communication; and (3) bicornuate uterus with a low cervical communication and atretic hemicervix. CONCLUSION: The 3 new types of nonisthmic communicating uteri constitute a new subclass of communicating uteri. We are aware of only 1 other reported type of nonisthmic communicating uteri. Nonisthmic communications may arise from a different mechanism than isthmic communications.  相似文献   
115.
116.

Background

Motor imagery (MI) impairment has been reported in individuals with multiple sclerosis (MS). The present study was designed to investigate neural evidence for MI impairment and its relationship to working memory in MS patients.

Methods

The study participants included 24 early stage MS patients (age: 22–40/mean = 32.7 years; M/F = 4/20; years since duration: 1–10/mean = 5.8) and 24 age-, gender-, and education-matched controls (age: 21–40/mean = 31.8 years; M/F = 5/19). Event-related potentials were recorded during a mental hand rotation task, in which participants were instructed to judge the laterality of hands displayed in different orientations. Furthermore, the Paced Auditory Serial Addition Test (PASAT) was used for assessment of working memory.

Results

At the behavioral level, MS patients were significantly less accurate and much slower (accuracy: 83.80 ± 7.72%; reaction time: 1665.95 ± 269.82 ms) than controls (accuracy: 88.35 ± 7.68%; reaction time: 1505.16 ± 225.11 ms). At the neural level, MS patients showed a significantly reduced amplitude (MS: 0.99 ± 0.89 μv, controls: 1.46 ± 1.00 μv) and delayed peak latency (MS: 458.45 ± 67.60 ms, controls: 417.91 ± 62.47 ms) at P3 for mental rotation effect. Moreover, there were significant correlations between individuals’ PASAT scores and performance of the hand rotation task.

Conclusion

The results of the present study demonstrate MI impairment in patients with MS at both the behavioral and neural level. Neuronal activity dysfunction (decreased and delayed activity) in patients with MS provides new insights into MI impairment. Furthermore, our findings suggest the contribution of working memory dysfunction to compromised MI ability in patients with MS.  相似文献   
117.
OBJECTIVES: The primary objective of this study was to assess the role of alcohol use and depression in intimate partner violence (IPV) victimization and perpetration among Blacks and Hispanics in an underserved urban emergency department population. METHODS: This cross-sectional study surveyed male and female patients presenting to an urban emergency department. The outcome measures were physical or sexual IPV victimization and perpetration in the previous 12 months. The independent predictors included demographic variables, alcohol and drug use, and depressive symptoms. Logistic regression analyses calculated the adjusted odds ratio (AOR) and 95% confidence interval (CI) for predictors of IPV victimization and perpetration in separate models. RESULTS: The prevalence of IPV victimization among Blacks and Hispanics were similar (14% and 10%, respectively) but blacks were nearly twice as likely to report IPV perpetration (17% vs. 9%, respectively). Predictors of IPV perpetration were Black race, married or living with a partner, heavy drinking, illicit drug use, and current depression. Depression, but not substance use, also predicted IPV victimization, in addition to Black race, married or living with a partner, and younger age. Screening for substance abuse and depression in an inner city emergency department population may help to identify individuals at high risk of IPV, particularly IPV perpetration.  相似文献   
118.
HYPOTHESIS: An increase in national utilization of bariatric surgery correlates with the dissemination of laparoscopic bariatric surgery. DESIGN: Evaluation of Nationwide Inpatient Sample data from 1998 through 2002. SETTING: National database. PATIENTS: A total of 188,599 patients underwent bariatric surgery for the treatment of morbid obesity. MAIN OUTCOME MEASURES: Annual total number of bariatric operations, the proportion of Roux-en-Y gastric bypass vs gastroplasty, the proportion of laparoscopic cases, postoperative length of stay, crude in-hospital mortality, and the number of institutions that perform bariatric surgery. RESULTS: Between 1998 and 2002, the number of bariatric operations increased from 12,775 cases to 70,256 cases. The rate of bariatric surgery increased from 6.3 to 32.7 procedures per 100,000 adults. Laparoscopic bariatric surgery increased from 2.1% to 17.9%. The number of bariatric surgeons with membership in the American Society for Bariatric Surgery increased from 258 to 631, and the number of institutions that perform bariatric surgery increased from 131 to 323. During this 5-year period, the annual rate of laparoscopic bariatric surgery increased exponentially (by 44-fold) compared with a linear growth in open bariatric surgery (by 3-fold). CONCLUSIONS: Between 1998 and 2002, there was a 450% increase in the number of bariatric operations performed in the United States, a 144% increase in the number of American Society for Bariatric Surgery bariatric surgeons, and a 146% increase in the number of bariatric centers. The growth of laparoscopic bariatric surgery during this 5-year period greatly exceeds that of open bariatric surgery.  相似文献   
119.
This study applied the Behavioral Model for Vulnerable Populations framework to examine the correlates of depression and the receipt of medical treatment among low-income Hispanics and African Americans residing in public housing. We compared three groups: those who reported (1) self-diagnosed but without physician-diagnosed depression, (2) depression diagnosed by a physician but who did not receive pharmaceutical treatment, and (3) depression diagnosed by a physician and antidepressant pharmacotherapy consumed by patient. Random samples of 287 adults from three public housing communities were surveyed. Over 48% of this sample reported that they were suffering from depression. One out of three people who reported being depressed also said that a physician had never diagnosed his or her condition. Only 40% of those who said that a physician had diagnosed depression also reported taking antidepressant medication. Untreated depression among underserved racial and ethnic minorities is alarming and points to an urgent need for intervention.  相似文献   
120.
Kainic acid, an analogue of glutamate, injected systemically to rats evokes seizures that are accompanied by nerve cell damage primarily in the limbic system. In the present study, we have analyzed the temporal profile of the expression of the cytokines interleukin-1beta (IL-1beta) and IL-1 receptor antagonist (IL-1ra), and the related IL-1beta-converting enzyme (ICE/caspase-1), in different regions of the rat brain in response to peripheral kainic acid administration (10 mg/kg, i.p.). In situ hybridization histochemistry experiments revealed that IL-1beta mRNA-expressing cells, morphologically identified as microglial cells, were mainly localized to regions showing pronounced neuronal degeneration; hippocampus, thalamus, amygdala, and certain cortical regions. The strongest expression of IL-1beta mRNA was observed after 12 hr in these regions. A weak induction of the IL-1beta mRNA expression was observed already at 2 hr. Similar results were obtained by RT-PCR analysis, showing a significantly increased expression of IL-1beta mRNA in the hippocampus and amygdala after 12 hr. In addition, RT-PCR analysis revealed that IL-1ra mRNA, and specifically mRNA encoding the secreted isoform of IL-1ra (sIL-1ra), was strongly induced in the hippocampus and amygdala at 12 and 24 hr post-injection. RT-PCR analysis of mRNA encoding caspase-1 showed a significantly increased expression in the amygdala after 12 hr. In conclusion, in response to systemic kainic acid injection IL-1beta mRNA is rapidly induced and followed by induction of IL-1ra mRNA and caspase-1 mRNA, supporting a role of the IL-1 system in the inflammatory response during excitotoxic damage.  相似文献   
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