An Expanded Self‐Medication Hypothesis Based on Cognitive‐Behavioral Determinants for Heroin Abusers in Taiwan: A Cross‐Sectional Study

Background: This study proposed and examined an expanded self‐medication hypothesis (eSMH) model based on cognitive behavioral determinants, including the direct effects of negative emotional states, positive outcome expectancies and refusal self‐efficacy on heroin use, and the mediating roles of positive outcome expectancies and refusal self‐efficacy between negative emotional states and heroin use. Methods: A total of 360 male heroin abusers were recruited from a drug abuse treatment center in Taiwan. Participants were asked to complete a set of questionnaires on frequency of heroin use, anxious/depressive mood, positive outcome expectancies, and refusal self‐efficacy. Structural equation modeling was used to examine the eSMH model. Results: Results showed that the eSMH model displayed proper goodness‐of‐fit. Positive outcome expectancies and negative emotional status were significant predictors of heroin use, whereas refusal self‐efficacy was not a significant predictor. Additionally, positive self‐efficacy was a mediator between negative emotional status and heroin use. Conclusion: Results support a reduced eSMH model and suggest a significant role of positive self‐efficacy in the relationship between negative affective states and heroin use. This relationship should be examined in the longitudinal study, and should be given clinical consideration in treatment of individuals struggling with heroin abuse and negative affective states. (Am J Addict 2012;21:S43–S48)     

Could metformin be used in patients with diabetes and advanced chronic kidney disease?

Diabetes is an important cause of end stage renal failure worldwide. As renal impairment progresses, managing hyperglycaemia can prove increasingly challenging, as many medications are contra‐indicated in moderate to severe renal impairment. Whilst evidence for tight glycaemic control reducing progression to renal failure in patients with established renal disease is limited, poor glycaemic control is not desirable, and is likely to lead to progressive complications. Metformin is a first‐line therapy in patients with Type 2 diabetes, as it appears to be effective in reducing diabetes related end points and mortality in overweight patients. Cessation of metformin in patients with progressive renal disease may not only lead to deterioration in glucose control, but also to loss of protection from cardiovascular disease in a cohort of patients at particularly high risk. We advocate the need for further study to determine the role of metformin in patients with severe renal disease (chronic kidney disease stage 4‐5), as well as patients on dialysis, or pre‐/peri‐renal transplantation. We explore possible roles of metformin in these circumstances, and suggest potential key areas for further study.     

Glucocorticoids Decrease Hippocampal and Prefrontal Activation during Declarative Memory Retrieval in Young Men

Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design. It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both hippocampal and prefrontal brain regions that are crucially involved in memory processing. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Computed tomographic staging of esophageal carcinoma: a study on interobserver variation and correlation with pathological findings.

Despite numerous reports on the efficacy of CT in the staging of esophageal carcinoma, no data are available on the reproducibility of the procedure. Three experienced radiologists independently reviewed the CT scans of 35 patients retrospectively. Calculation of interobserver variation was performed using the kappa statistic. The CT findings of each observer were subsequently correlated with the surgical and pathological findings of 17 patients. There was a large interobserver variation concerning involvement of the aorta, pulmonary vessels, vertebral column, stomach and lymph nodes, ranging from poor to excellent agreement. Agreement between observers on extension of the disease to the tracheobronchial tree, pericardium and liver was good or excellent. Agreement between the CT findings of all observers and the surgical findings for invasive growth was poor. CT pathological correlation of the three observers showed sensitivities ranging from 50 to 57%, specificities ranging from 50 to 60% and accuracies ranging from 46 to 71%. It can be concluded from this study that patients with positive CT findings for involvement of the tracheobronchial tree, the pericardium and the liver should be considered unresectable for cure. Negative findings, however, should be interpreted with caution, because involvement of other structures may still be present. Despite optimistic reports on the efficacy of CT in the pretherapy staging of esophageal neoplasms, this modality has its limitations.     

Major Neurological Disease and Occupational Exposure to Organic Solvents

Five patients are described who presented with major organicbrain disease affecting one or more of pyramidal and extrapyramidaltracts, cerebellum, and higher cortical functions. All had ahistory of 10 years or more of regular occupational exposureto solvents in confined spaces, three in painting inside shipsand the others in weapons maintenance and printing. All hadbeen regularly exposed to high air vapour peaks as well as toskin contamination. Four showed some evidence of improvementafter the exposure ceased. None was initially suspected of havinga toxic encephalopathy by the consultant to whom he was referred.The spectrum of neurological disease presented by these menmirrors closely that described in solvent abusers. All wereforced by illness to retire from their work, a circumstancewhich might have in the past have led to such conditions beingmissed in cross-sectional studies, which in general have notshown evidence of major disease. We suggest that when such diseaseoccurs nowadays, its cause is usually not suspected. Furtherepidemiological study of the problem is necessary.