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Background: Structural imaging studies of cannabis users have found evidence of both cortical and subcortical volume reductions, especially in cannabinoid receptor-rich regions such as the hippocampus and amygdala. However, the findings have not been consistent. In the present study, we examined a sample of adult heavy cannabis users without other substance abuse to determine whether long-term use is associated with brain structural changes, especially in the subcortical regions.Method: We compared the gray matter volume of 14 long-term, heavy cannabis users with non-using controls. To provide robust findings, we conducted two separate studies using two different MRI techniques. Each study used the same sample of cannabis users and a different control group, respectively. Both control groups were independent of each other. First, whole-brain voxel-based morphometry (VBM) was used to compare the cannabis users against 28 matched controls (HC1 group). Second, a volumetric analysis of subcortical regions was performed to assess differences between the cannabis users and a sample of 100 matched controls (HC2 group) obtained from a local database of healthy volunteers.Results: The VBM study revealed that, compared to the control group HC1, the cannabis users did not show cortical differences nor smaller volume in any subcortical structure but showed a cluster (p < 0.001) of larger GM volume in the basal ganglia, involving the caudate, putamen, pallidum, and nucleus accumbens, bilaterally. The subcortical volumetric analysis revealed that, compared to the control group HC2, the cannabis users showed significantly larger volumes in the putamen (p = 0.001) and pallidum (p = 0.0015). Subtle trends, only significant at the uncorrected level, were also found in the caudate (p = 0.05) and nucleus accumbens (p = 0.047).Conclusions: This study does not support previous findings of hippocampal and/or amygdala structural changes in long-term, heavy cannabis users. It does, however, provide evidence of basal ganglia volume increases.

Background: Structural imaging studies of cannabis users have found evidence of both cortical and subcortical volume reductions, especially in cannabinoid receptor-rich regions such as the hippocampus and amygdala. However, the findings have not been consistent. In the present study, we examined a sample of adult heavy cannabis users without other substance abuse to determine whether long-term use is associated with brain structural changes, especially in the subcortical regions. Method: We compared the gray matter volume of 14 long-term, heavy cannabis users with non-using controls. To provide robust findings, we conducted two separate studies using two different MRI techniques. Each study used the same sample of cannabis users and a different control group, respectively. Both control groups were independent of each other. First, whole-brain voxel-basedmorphometry (VBM) was used to compare the cannabis users against 28 matched controls (HC1 group). Second, a volumetric analysis of subcortical regions was performed to assess differences between the cannabis users and a sample of 100 matched controls (HC2 group) obtained from a local database of healthy volunteers. Results: The VBM study revealed that, compared to the control group HC1, the cannabis users did not show cortical differences nor smaller volume in any subcortical structure but showed a cluster (p < 0.001) of larger GM volume in the basal ganglia, involving the caudate, putamen, pallidum, and nucleus accumbens, bilaterally. The subcortical volumetric analysis revealed that, compared to the control group HC2, the cannabis users showed significantly larger volumes in the putamen (p = 0.001) and pallidum (p = 0.0015). Subtle trends, only significant at the uncorrected level, were also found in the caudate (p = 0.05) and nucleus accumbens (p = 0.047). Conclusions: This study does not support previous findings of hippocampal and/or amygdala structural changes in long-term, heavy cannabis users. It does, however, provide evidence of basal ganglia volume increases. [ABSTRACT FROM AUTHOR]

Objectives Apparently, depot-medroxyprogesterone acetate (DMPA) increases a woman's risk of acquiring HIV. The objective of this study was to test whether the vaginal mucosal thickness and Langerhans cell counts were significantly different in long-term DMPA users compared with women users of an intrauterine device (IUD) who had never used DMPA. Study design Cross-sectional study. Twenty-three DMPA users were matched with 23 nonusers controlled for age, body mass index (BMI; kg/m²), and duration of contraceptive use. Four groups of women were evaluated according to the duration of DMPA use: > 1, < 5; ≥ 5, < 10; ≥ 10, < 15 or ≥ 15 years. Estradiol (E2) levels were compared between the two groups. Histologic sections of vaginal mucosal biopsies were evaluated to measure the mean epithelial thickness and S100 immunostained sections were used to count the number of Langerhans cells/mm. Results Mean (± S.D.) E2 levels were significantly lower in DMPA users (39.4±26.6 pg/mL) compared with nonusers (102.6±60.3 pg/mL) despite similar ages (42.3±7.4 and 42.4±7.4 years, respectively). Mean (± S.D.) vaginal thickness was 232.6±108.1 and 229.7±112.9 in DMPA users and nonusers, respectively. There were no differences in vaginal thickness or Langerhans cell count/mm between users and nonusers even after controlling for DMPA duration of use. Conclusions Vaginal epithelial thinning or Langerhans cell count was not different between long-term DMPA users and copper-IUD users who had never used DMPA. Implications No differences were found in vaginal epithelial thickness or in Langerhans cell count between long-term users of the injectable contraceptive DMPA and nonusers. [ABSTRACT FROM AUTHOR]

Although audit support systems have been deployed for over a decade, they continue to evolve. Technological advances present audit firms with the ongoing dilemma of deciding the type and extent of decision support to embed within their firm's system. This exploratory study complements the existing literature that has investigated the short-term consequences of providing decision support to auditors by investigating the association between the extent of decision support embedded within the audit support systems of three major international audit firms and the declarative knowledge possessed by long-term users. An experiment was conducted which required auditors, without the aid of their firm's audit support system, to list the key business risks common to clients in an industry familiar to them (hereafter referred to as relevant risks). As predicted, we find that auditors who normally use an audit support system that provides a low level of decision support list more relevant risks. This exploratory study provides preliminary evidence of a long-term consequence of providing decision support. The results will assist audit firms in their continued development of audit support systems. [ABSTRACT FROM AUTHOR]

This study investigates the impact of physical illness, health locus of control and anxiety level on long- and short-term benzodiazepine (BZD) use in patients of an internal medicine department. There was no significant difference observed between the continuing and discontinuing group after hospital admission in terms of average daily dose of BZD. However, the continuing patients rated the condition of their somatic illness significantly higher than the discontinuing group, although this difference was not confirmed by the objective assessment of the treating physician. The non-continuing group displayed significantly higher control over health- and sickness-related events. The somatic and physical anxiety factor was significantly higher in the continuing group at initial investigation as well as at follow-up. On the basis of these results, we conclude that an increased focus on the psychosomatic element might reduce the risk of long-term tranquiliser use in patients with physical illness.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]