Antinociceptive and thermoregulatory actions of vasopressin are sensitive to a V1-receptor antagonist.

The involvement of arginine vasopressin (AVP) has been investigated in cold water swim (CWS) stress-induced antinociception (SIA) and CWS-induced hypothermia. The antinociceptive action of AVP (0.5 micrograms, i.c.v.) pre-CWS was antagonized by d(CH2)5Tyr(Me)AVP (0.5 micrograms, i.c.v.) but not by naloxone (5 micrograms, i.c.v.). CWS produced SIA on the hot-plate which was initially naloxone-insensitive. Neither AVP nor its antagonist had any significant effect on CWS SIA. AVP-induced increase in body temperature, during recovery from CWS-induced hypothermia, was significantly (P < 0.001) reduced in the presence of its antagonist. These findings suggest that the antinociceptive and thermoregulatory actions of AVP may be mediated via V1-receptors.     

Vasopressin and stress-induced antinociception in the mouse.

1. Arginine vasopressin produced antinociception in the hot-plate test after intracerebroventricular injection (0.5 micrograms) and in the acetic acid abdominal constriction test after intraperitoneal injection (0.1 mg kg-1). 2. The antinociception produced by arginine vasopressin was sensitive to deamino(CH2)5Tyr(Me) arginine vasopressin (0.5 micrograms i.c.v.; 0.1 mg kg-1 i.p.) but not to naloxone (5 micrograms i.c.v.; 2 mg kg-1 i.p.) 3. Arginine vasopressin when administered by the intracerebroventricular route, but not by the intraperitoneal route, produced characteristic behaviour which was sensitive to deamino(CH2)5Tyr(Me) arginine vasopressin (0.5 micrograms, i.c.v.). 4. A 3 min swim at 20 degrees C produced antinociception on the hot-plate which was sensitive to naloxone (0.4 mg kg-1, i.p.) but not to deamino(CH2)5Tyr(Me) arginine vasopressin (0.5 micrograms, i.c.v.). 5. The reduction in the number of acetic acid-induced abdominal constrictions produced by a 30 s swim at 30 degrees C was not sensitive to either naloxone (2 mg kg-1, i.p.) or deamino(CH2)5Tyr(Me) arginine vasopressin (0.1 mg kg-1, i.p.). 6. Arginine vasopressin, at high doses, is antinociceptive in the mouse but does not appear to mediate stress-induced antinociception in this species.     

SARs at the Monoamine Transporters for a Novel Series of Modafinil Analogues

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Pre-school hearing screening: Profile of children from Ogbomoso,Nigeria

Objectives

To carry out otoscopic and audiologic examinations amongst pre-school children in Ogbomoso, Nigeria in order to identify any cases of hearing loss and to intervene where possible.

Study design and setting

Prospective audiologic evaluations of children in Nursery I and II (pre-kindergarten and kindergarten) in both private and public primary schools were carried out.

Methods

One hundred and one children (202 ears) were screened using otoscopy and pure tone audiometry.

Results

The age ranged from 3.5 to 6 years, mean age was 4.8 years (S.D. = 0.835), with a male population of 55 and 46 females (M:F ratio, 1.2:1). Otoscopic findings revealed normal findings (106) 52.4%, impacted cerumen auris, 44 (21.8%), otitis media with effusion, (28) 13.9%, perforated tympanic membrane, 24 (11.9%) and giving an otoscopic pass rate of 52.4%. Screening audiometry, on the other hand, recorded a pass rate of 78.7%. After 6–8 weeks of otolaryngologic intervention, the otoscopic pass rate improved to 88.6%, while the pass rate for screening audiometry also improved to 93.6%.

Conclusion/significance

From the study, an otoscopic pass rate of 52.9% and screening audiometry pass rate of 78.7% increased to 88.6% and 93.6%, respectively, through basic otolaryngologic interventions. The key roles played in identifying ear diseases with or without hearing impairments with the use of clinical examination (otoscopy) and audiologic evaluation in the pre-school age children has been highlighted in the study. Unfortunately, these evaluations are not performed routinely in children enrolled in both private and public primary schools in Ogbomoso, Nigeria. We advocate that the routine otoscopic examinations with screening audiometry be made available in all primary schools, in order to facilitate early detection and prompt rehabilitation of children with ear diseases and hearing impairment.     

Determinants of transition across the spectrum of alcohol use and misuse in Nigeria

Many studies have examined the risk factors associated with alcohol use disorders. No information is available from developing countries about the factors that may determine the transitions across different levels of use and misuse. Alcohol use and its misuse were assessed in a cohort of 2143 Nigerians using Version 3.0 of the World Health Organization Composite International Diagnostic Interview (WHO-CIDI). This generated six levels of alcohol use and related disorders. Using age of onset variables created for the purpose, analysis was done to determine rates of and risk factor for transition between the levels. Lifetime prevalence estimates were 57.8% for alcohol use, 27.6% for regular use, 2.9% for abuse, and 0.3% for dependence. Whereas 47.8% transited to regular use from lifetime ever use, only 10.5% transited to abuse from regular use and 9.5% from abuse to dependence. Male sex, age 18–49 years and being never married predicted onset of alcohol use. Transition to regular use was predicted only by male sex while transition to abuse was predicted by male sex and age 35–49 years. Factors associated with recovery from abuse were female sex and a student status. Higher rates of transition occurred in the stages preceding the onset of alcohol use disorders. Sex and age were the main determinants of transition, with male gender and middle age being risk factors for transition to problematic use of alcohol.     

Primary Effusion Lymphoma with Central Nervous System Involvement in an HIV-Negative Homosexual Male

Primary effusion lymphoma (PEL) is a rare form of non-Hodgkin lymphoma that presents with body cavity effusions. It occurs chiefly in immunodeficient HIV-positive patients. The tumor cells generally express gene sequences of human herpesvirus-8 (HHV-8) and Epstein-Barr virus (EBV). Tumor cells of HIV-negative patients usually express HHV-8 gene sequences, but rarely those of EBV. We report a novel case of PEL in an HIV-negative homosexual male whose tumor cells expressed both HHV-8 and EBV gene sequences and who developed evidence of central nervous system involvement.