Independent effects of tobacco abstinence and bupropion on cognitive function in schizophrenia

OBJECTIVE: The objective of this study was to examine the effects of tobacco abstinence and bupropion treatment on cognitive functioning in adult smokers with schizophrenia in the setting of a randomized, double-blind, placebo-controlled clinical trial of bupropion for smoking cessation. METHOD: Fifty-three adults with schizophrenia (DSM-IV) took part in a trial of bupropion for smoking cessation. Subjects were enrolled in the study from August 1999 to March 2003. Forty-five subjects remained in the trial at week 4; 41 subjects, 19 taking bupropion and 22 taking placebo, completed the baseline and week 4 cognitive assessments and were included in the analysis of adjusted effects of abstinence and bupropion treatment on cognitive function. RESULTS: Controlling for bupropion treatment and baseline performance, 7 days of tobacco abstinence was associated with slowed motor speed (finger tapping) but was not associated with worsening of performance on tests of attention (AX Continuous Performance Test [AX-CPT]), verbal learning and memory (California Verbal Learning Test [CVLT]), working memory (digit span), or executive function/inhibition (Stroop) and was not associated with worsening of any clinical measures. Controlling for abstinence status, bupropion was associated with reduction (improvement) in reaction time variability on the AX-CPT and with reduction in perseverative errors on the CVLT. CONCLUSION: We conclude that 1 week of tobacco abstinence is associated with slowed motor speed but is not associated with detectable worsening in performance on a range of neuropsychological tests or clinical symptoms in the subset of patients who were able to quit smoking. We also conclude that bupropion treatment may be associated with improvement in variability of attention.     

HIV-1 diversity and prevalence differ between urban and rural areas in the Mbeya region of Tanzania

OBJECTIVE: To characterize HIV-1 strains in a potential vaccine trial cohort (CODE) in the Mbeya region of southwest Tanzania. DESIGN: Study volunteers (n = 3096) were recruited from urban areas in Mbeya Town, using two different recruitment strategies, and in a nearby rural village. METHODS: Cryopreserved plasma from 507 HIV-1 prevalent cases was the source of viral RNA for HIV-1 genotyping by the Multi-region Hybridization Assay, the MHA(acd), and selected strains were confirmed by complete genome sequencing. RESULTS: The overall HIV-1 prevalence was 16.6% [95% confidence interval (CI), 15.3-17.9] within the cohort. HIV-1 prevalence was higher among women, and in urban areas. Recruitment through advertisement targeted a high-risk urban male population for HIV-1 infection [adjusted odds ratio (adj. OR), 1.68; 95% CI, 1.13-2.51] when compared with men recruited door-to-door. The complexity of the HIV-1 epidemic was also higher in urban areas evidenced by the high-risk of HIV-1 infection with a recombinant strain (adj. OR, 2.69; 95% CI, 1.08-6.69) and HIV-1 dual infection (adj. OR, 5.16; 95% CI, 1.07-24.9), mainly driven by urban men recruited through advertisement. CONCLUSIONS: Overall the urban epidemic was more genetically complex, with higher prevalence and more recombinants and dual infections. Vaccine trials in Mbeya region can assess a complex HIV-1 population dynamic and determine vaccine efficacy in relationship to the genetic diversity of HIV-1 strains that challenge vaccines.     

Volume determination of intracranial aneurysms using 16-row multislice computed tomography angiography: a systematic in vitro analysis of different reconstruction methods

OBJECTIVE: To assess multislice computed tomography (CT) angiography for volume determination of intracranial aneurysms. METHODS: Submillimetric 16-row multislice CT angiography was performed with optimized scan parameters on precision spheres and a soft carotid artery model harboring 3 aneurysms connected to a pulsatile circuit. The CT angiography images were produced using optimized techniques for axial, multiplanar reformation, maximum intensity projection, surface-shaded display, and volume-rendered images. Measurements were made with electronic precision calipers by segmentation according to the method of Cavalieri and by the use of automated volumetric analysis software. RESULTS: Segmentation resulted in precise and accurate volume estimates of aneurysms, but small volumes were underestimated and evaluation time was long (36:44 minutes). Automated volume evaluation from volume-rendered reconstructions also resulted in low measurement error, although the evaluation process was significantly faster (3:25 minutes; P < 0.0001). CONCLUSIONS: The use of an automated volume analysis tool on volume-rendered reconstructions is recommended for time-efficient volume assessment of intracranial aneurysms.     

Detectability of liver metastases in malignant melanoma: prospective comparison of magnetic resonance imaging and positron emission tomography

PURPOSE: We evaluated the diagnostic accuracy of magnetic resonance imaging (MRI) and positron emission tomography (PET) for detection of liver metastases in malignant melanoma. MATERIAL AND METHODS: Thirty-five patients with 39 combined unenhanced MRI and fluorine-18 deoxyglucose (F-18 FDG) PET scans were prospectively studied. In discordant imaging findings final diagnosis was proven by clinical follow-up >6 months and demonstration of progressive liver metastases by at least one imaging method. Sensitivities and specificities were compared and the influence of lesion size and melanin content on diagnostic accuracy was determined. RESULTS: MRI and PET were concordantly negative for presence and number of liver metastases in 28 patients and positive in four patients. PET and MRI were false positive in one patient each. In one patient MRI showed a single metastases not seen by PET and in one patient MRI demonstrated more metastases at the first examination. In follow-up investigations MRI revealed more metastases than PET in both patients. The sensitivities for lesion detection were 47% (16/34) for PET and 100% for MRI. Lesion detectability by PET was related to lesion size (P < 0.0001) but not to melanin content. CONCLUSION: MRI is more sensitive in the detection of liver metastases in patients with malignant melanoma. Small lesions are easily missed by PET, while melanin content does not influence detectability by PET.     

Nerve fibres are required to evoke a contact sensitivity response in mice

Previous work has indicated that the dermis and epidermis of skin contains abundant nerve fibres closely associated with Langerhans' cells. We have investigated whether these nerve endings are necessary for inducing and evoking a contact sensitivity (CS) response. Topical application of a general or a peptide (calcitonin gene-related peptide and substance P)-specific neurotoxin was employed to destroy the nerve fibres at skin sites subsequently used to induce or evoke the CS response. Elimination of nerve fibres abolished both induction and effector stages of the specific CS response. Denervation did not destroy the local Langerhans' cells, which were observed in increased numbers, or prevent them from migrating to lymph nodes. The local CS response was also abolished by systemic deletion of capsaicin-sensitive nerve fibres, suggesting that the loss of response was not non-specific but associated with the loss of specific nerve fibres. The results indicate that peptidergic nerve fibres are required to elicit a CS response and may be vital to the normal function of the immune system.     

Antibody response of wild birds to natural infection with alphaviruses

From 1986 to 1990, we conducted our second longitudinal study in the central (upstate) New York (CNY) area on the wild avian hosts of eastern equine encephalomyelitis (EEE) virus. Field-collecting methods mirrored a study conducted from 1978 to 1980 at the same endemic focus. Over the 5-yr study period, we captured 6,296 birds representing 99 species and took 4,174 blood samples from representatives of 83 species. Gray catbirds, song sparrows, and veerys were the three dominant species captured and bled, accounting for 40 and 55% of birds captured and bled. Blood clots were assayed for virus and sera tested for hemagglutination-inhibition (HI) antibodies to EEE and Highlands J virus. Virus isolations from birds defined two epiornitics of EEE virus in 1988 and 1990, and an epiornitic of HJ virus in 1986. Infected birds responded with the production of HI antibodies with titers indicative of recent infection (HI > or = 1:160), and titers of sera positive during the epiornitics were significantly higher than positive sera during nonepiornitics. The 1990 EEE epiornitic extended from mid-July to the end of September, providing data to compare infection rates among species, habitats, and combinations of species with habitats. Few significant differences were found. The HJ epiornitic was only the second time this virus has occurred in CNY. Song sparrows were identified as the primary amplifying avian host of both viruses, although our capture and serological data would suggest a role for gray catbirds as the species most likely involved in yearly virus reintroduction. However, the cryptic nature of enzootic virus maintenance remains unresolved for the CNY virus foci. The appearances of HJ and EEE viruses were not epidemiologically linked, and there were no virus isolations from adults returning on site or virus isolations without concurrent isolations from mosquito vectors. Whether EEE and/or HJ virus are consistently present in or sporadically introduced into the inland foci of CNY area still has not been determined.     

Miconazole oral gel and drug interactions

Miconazole oral gel is frequently prescribed for the treatment of oral Candidal infections. Its ability to be systemically absorbed and interact with other drugs has previously been recorded but is not universally known. As a reminder, a further case of derangement of anticoagulation following concomitant use of warfarin and miconazole is reported. Other potential drug interactions of miconazole and fluconazole are highlighted.     

Comparison of immunogenicity and tolerability of a virosome-adjuvanted and a split influenza vaccine in children

OBJECTIVE: To compare the immunogenicity and safety of a virosome-adjuvanted influenza vaccine (Inflexal V; Berna Biotech, Berne, Switzerland) and a split influenza vaccine (Fluarix; GlaxoSmithKline Biologicals, Rixensart, Belgium) in children. SUBJECTS AND METHODS: The subjects, 453 children ages 6 to 71 months, were stratified into primed and unprimed and age groups (6 to 35 and 36 to 71 months) and then randomized 1:1 to receive virosome-adjuvanted (n = 224) or split influenza vaccine (n = 229), a half or full dose was given intramuscularly according to age. Unprimed children received a second dose after 4 weeks. Blood samples (n = 326) collected pre-and 28 days postvaccination were analyzed by hemagglutination inhibition test. Safety assessments were made at baseline and follow-up visits by the investigators and by parents for the 4 days after vaccinations. RESULTS: Both vaccines induced an effective immune response. Seroconversion rates (>4-fold titer rise) against the WHO recommended strains A/New Caledonia (H3N2), A/Moscow (H1N1) and B/Hongkong (B) were 80.1, 66.0 and 90.4% for the virosome-adjuvanted and 75.9, 62.9 and 89.4% for the split influenza vaccine, respectively. Unprimed children's seroconversion rates for H3N2 were significantly higher (P = 0.02) for the virosome-adjuvanted (88.8%) than for split influenza vaccine (77.5%). Seroprotection rates (titer of > 40) for H3N2, H1N1 and B, respectively, were 87.8, 80.1 and 90.4% after vaccination with the virosome-adjuvanted vaccine and 82.9, 78.2 and 89.4% after the split influenza vaccine. Unprimed children's seroprotection rate was significantly higher (P = 0.03) for H3N2 after the virosome-adjuvanted (88.8%) than those for the split influenza vaccine (78.3%). Equivalent geometric mean titer fold increases were evident for both vaccines. No serious adverse events were seen. Pain/ tenderness, redness and swelling/induration was found in 25.4, 11.2 and 8.9% for the virosome-adjuvanted vaccine and in 24.0, 9.2 and 6.1% for the split influenza vaccine, respectively. The rates of fever, malaise/irritability and shivering was 6.3, 11.6 and 2.7% for the virosome-adjuvanted vaccine and 8.3, 11.8 and 2.6% for the split influenza vaccine, respectively. CONCLUSIONS: The virosome-adjuvanted influenza vaccine showed greater immunogenicity over the split influenza vaccine in unprimed children and showed a trend toward better immunogenicity in the rest of the study population. Both vaccines were well-tolerated.