Dissociable Control of Impulsivity in Rats by Dopamine D2/3 Receptors in the Core and Shell Subregions of the Nucleus Accumbens

Previous research has identified the nucleus accumbens (NAcb) as an important brain region underlying inter-individual variation in impulsive behavior. Such variation has been linked to decreased dopamine (DA) D2/3 receptor availability in the ventral striatum of rats exhibiting spontaneously high levels of impulsivity on a 5-choice serial reaction time (5-CSRT) test of sustained visual attention. This study investigated the involvement of DA D2/3 receptors in the NAcb core (NAcbC) and the NAcb shell (NAcbS) in impulsivity. We investigated the effects of a DA D2/3 receptor antagonist (nafadotride) and a DA D2/3 partial agonist (aripiprazole) infused directly into either the NAcbC or NAcbS of rats selected for high (HI) and low (LI) impulsivity on the 5-CSRT task. Nafadotride increased significantly the level of impulsivity when infused into the NAcbS, but decreased impulsivity when infused into the NAcbC of HI rats. By contrast, intra-NAcb microinfusions of aripiprazole did not affect impulsivity. Systemic administration of nafadotride had no effect on impulsive behavior but increased the number of omissions and correct response latencies, whereas systemic injections of aripiprazole decreased impulsive and perseverative behavior, and increased the number of omissions and correct response latencies. These findings indicate an opponent modulation of impulsive behavior by DA D2/3 receptors in the NAcbS and NAcbC. Such divergent roles may have relevance for the etiology and treatment of clinical disorders of behavioral control, including attention-deficit hyperactivity disorder and drug addiction.     

Spinal haematoma following epidural anaesthesia in a patient with eclampsia

A patient with a twin pregnancy required a Caesarean section for severe pre-eclampsia. Her platelet count was 71 x 10(9).l-1. Epidural anaesthesia was performed after platelet transfusion. A spinal epidural haematoma was diagnosed postoperatively. A generalised tonic-clonic seizure sparing the lower limbs enabled early diagnosis to be made. The patient recovered with no permanent neurological damage after laminectomy and clot removal. The risks and benefits of regional techniques require careful consideration, and postoperative monitoring for recovery of neural blockade is essential.     

Emotional demands at work and risk of hospital-treated depressive disorder in up to 1.6 million Danish employees: a prospective nationwide register-based cohort study

ObjectivePrevious studies on effects of emotional demands on depression have relied on self-reported exposure data and lacked control for potential confounding by pre-employment risk factors for depression. This study used a register-based design to examine the risk of hospital-treated depressive disorder in relation to occupational levels of emotional demands at work, furthermore addressing the role of risk factors for depression before workforce entry.MethodsWe analyzed data from two Danish register-based cohorts – Job Exposure Matrix Analyses of Psychosocial Factors and Healthy Ageing in Denmark (JEMPAD, N= 1 665 798) (17) and Danish Work Life Course Cohort (DaWCo, N=939 411), which link assessments of emotional demands by job exposure matrices to records of hospital-treated depressive disorder among employees aged 15–59 years at baseline (average follow up: 9.7 years in JEMPAD, 7.3 years in DaWCo). Potential confounders comprised sociodemographics, job control, work-related violence and physical demands at work. In DaWCo, we followed individuals from their entry into the workforce, and also included data on risk factors for depression before workforce entry (eg, parental income, education, and psychiatric diagnoses).ResultsEmployees in occupations with high emotional demands had an increased risk of hospital-treated depressive disorder with confounder-adjusted hazard ratios of 1.32 [95% confidence interval (CI) 1.24‒1.41] and 1.19 (95% CI 1.09‒1.30) in JEMPAD and DaWCO, respectively. This association remained after controlling for risk factors before workforce entry.ConclusionsThis study suggests that employees in occupations with high emotional demands are at increased risk of hospital-treated depressive disorder. This increased risk was neither attributable to reporting bias nor explained by the included risk factors for depression recorded before workforce entry.     

Physical and cognitive domains of the Instrumental Activities of Daily Living: validation in a multiethnic population of Asian older adults

BACKGROUND: We sought to assess the validity of the physical and cognitive domains of Lawton and Brody's Instrumental Activities of Daily Living (IADL) scale and its cross-cultural applicability across ethnic groups in an Asian population of community-living older adults. METHODS: Using data from a random population sample of noninstitutionalized Chinese, Malay, and Indian older adults 60 years old and older in Singapore (N = 1072), we modeled the dimensional structure of the 8-item IADL Scale using exploratory and confirmatory factor analyses, and assessed its convergent and divergent validity using known group differences and strengths of association. RESULTS: Factor analyses yielded two strong and reliable factors representing underlying physical and cognitive dimensions of IADL. The validity of the model was supported by the pattern of associations of the IADL with age, gender, education, self-reported health status, hospitalization, physical comorbidities, dementia and depression, and Mini-Mental State Examination (MMSE) scores. Notably, cognitive IADL showed a greater total effect on MMSE cognitive performance score than did physical IADL, with the effect of physical IADL on MMSE score mostly explained by cognitive IADL. Reasonably good cross-cultural validity was demonstrated among Chinese, Malays, and Indians, with strongest validity for Indians. CONCLUSION: The eight-item IADL Scale has physical and cognitive domains and is cross-culturally applicable. The cognitive IADL domain taps a set of activities directly related to cognitive functioning.     

False-negative serological HLA-B27 typing results may be due to altered antigenic epitopes and can be detected by polymerase chain reaction

Serological typing with the microlymphocytotoxicity test (MLCT) and flow cytometry (FC) using HLA-B27 antisera is commonly used for the determination of HLA-B27. However, in some patients tested more than once, negative results have turned out to be positive at following investigations. We retested by polymerase chain reaction (PCR) samples from 20 randomly selected patients with reactive arthritis or Reiter's syndrome who had now been followed for 20 yr. Ten of the patients were originally tested to be HLA-B27 positive and 10 HLA-B27 negative by the MLCT. All 10 serologically HLA-B27 positive individuals were also positive in the PCR. However, 2/10 patients interpreted as being HLA- B27 negative were positive by PCR. At this time, the same two patients were also positive in the routine MLCT and FC using four different monoclonal antibodies against HLA-B27. PCR is superior to serological techniques to determine HLA-B27 positivity unequivocally, since it is based on the detection of HLA-B27 gene sequences.      

Management of oral complications of disease-modifying drugs in rheumatoid arthritis

Stomatitis is a troublesome adverse effect of disease-modifying anti- rheumatic drug (DMARD) therapy in rheumatoid arthritis (RA) patients. This review presents data to examine the incidence, clinical features and consequences of DMARD-related stomatitis, and suggests an algorithm for its clinical management. The specific objectives of the two studies presented here were to determine the incidence of DMARD-related stomatitis and its effect on DMARD continuation, and secondly to identify the clinical and laboratory risk factors. We investigated two cohorts of patients: (i) a retrospective survey of data collected from drug monitoring clinics run for patients on DMARDs from 1987 to 1994 involving 1539 patients and 2394 drug exposures; (ii) a prospective study of 25 consecutive RA patients presenting with DMARD-related stomatitis compared to 29 RA controls with no history of DMARD stomatitis. The retrospective survey showed that 2% of DMARD patients stopped therapy because of stomatitis, but 55% of these were able to resume the same therapy. In the case control study. 24% of patients discontinued temporarily and 8% permanently. Cases of DMARD-related stomatitis differed from controls in that they had a higher incidence of previous mouth ulcers (40% vs 14%), they smoked less (8% vs 31%) and Schirmer's test was more often abnormal (44% vs 21%). There were no differences in RA severity, disease activity or oral hygiene. Haematinic deficiencies were equally common in cases and controls: 30% for iron, 8% for vitamin B12 and 24% for folic acid. Herpes simplex virus was involved in a minority (8%) of cases. In conclusion, the occurrence of stomatitis in RA patients on DMARD should not lead to cessation of drug therapy, but to a careful evaluation so that patients may be maintained on effective treatment.      

Cryoinjury with compartment syndrome of bilateral hands secondary to Freon gas: a case report and review of current literature

Freon is an industrial refrigerant that can result in serious cryoinjury of the skin. Although there had been a few reported cases, the optimal management is not clear. We present the first case report of a patient with freon-induced cryoinjury of bilateral hands, complicated with compartment syndrome and treated with a combination of surgical decompression, negative-pressure wound therapy (NPWT), and hyperbaric oxygen therapy (HBOT). On follow-up, there was a complete healing without tissue loss or significant atrophy of the intrinsic muscles of the hand. Therefore, we opined that HBOT and NPWT may work synergistically to prevent progressive tissue damage and improve the long-term outcome, especially when vascularity is compromised in severe cryoinjuries of the hand.Level of Evidence: Level V, therapeutic study.