Manual skill,hand skill asymmetry,and cognitive performances in young children

A total of 1022 children aged 3 to 6 years were examined in their preschools and 27% of them were followed up for 2 years. A computerised version of the peg‐moving task was used repeatedly to assess hand skill of the dominant and the nondominant hand. Cognitive performance was repeatedly evaluated by tasks involving speech, vocabulary, phonological memory, and visual‐spatial skills. Results showed that: (i) age, sex, and handedness effects on hand skill asymmetry generally confirmed previous reports, especially by Annett (2002); (ii) visual‐spatial and vocabulary tasks were significantly related to hand skill but speech and phonological memory tasks were not, and the role of the dominant and nondominant hand were similar; (iii) overall, manual laterality indexes were only weakly associated to some cognitive abilities; (iv) early manual skill was more strongly associated to cognitive tasks than later manual skill. These results fit the assumption of a significant role of early manual behaviour in aspects of cognitive development not relying exclusively on phonology, and raise questions about cognitive development and rehabilitation of children with early occurring manual deficiencies.     

Impact of tuberculosis on mortality among HIV-infected patients receiving antiretroviral therapy in Uganda: a prospective cohort analysis

Background

Tuberculosis (TB) disease affects survival among HIV co-infected patients on antiretroviral therapy (ART). Yet, the magnitude of TB disease on mortality is poorly understood.

Methods

Using a prospective cohort of 22,477 adult patients who initiated ART between August 2000 and June 2009 in Uganda, we assessed the effect of active pulmonary TB disease at the initiation of ART on all-cause mortality using a Cox proportional hazards model. Propensity score (PS) matching was used to control for potential confounding. Stratification and covariate adjustment for PS and not PS-based multivariable Cox models were also performed.

Results

A total of 1,609 (7.52%) patients had active pulmonary TB at the start of ART. TB patients had higher proportions of being male, suffering from AIDS-defining illnesses, having World Health Organization (WHO) disease stage III or IV, and having lower CD4 cell counts at baseline (p?<?0.001). The percentages of death during follow-up were 10.47% and 6.38% for patients with and without TB, respectively. The hazard ratio (HR) for mortality comparing TB to non-TB patients using 1,686 PS-matched pairs was 1.37 (95% confidence interval [CI]: 1.08 – 1.75), less marked than the crude estimate (HR?=?1.74, 95% CI: 1.49 – 2.04). The other PS-based methods and not PS-based multivariable Cox model produced similar results.

Conclusions

After controlling for important confounding variables, HIV patients who had TB at the initiation of ART in Uganda had an approximate 37% increased hazard of overall mortality relative to non-TB patients.

     

Aetiology of childhood hearing loss in Cameroon (sub-Saharan Africa)

BackgroundSevere hearing loss is a global problem affecting particularly developing countries. There is scarcity of recent published data on the epidemiology of childhood deafness in sub-Saharan Africa.ObjectiveTo determine the etiological profile of severe childhood deafness in Cameroon.MethodsProspective cross-sectional study of patients with a severe hearing loss that started before the age of 15 years. Detailed family and medical history was obtained; careful clinical, otological and audiological examinations were performed.ResultsA total of 582 patients with a severe hearing loss were examined. Prelingual deafness accounted for 75.1% (n = 437), with a mean age at medical diagnosis of 3.3 ± 1.2 years. This late presentation may be explained by limited parental awareness of signs raising suspicion of hearing loss, poor access to health care and the absence of neonatal screening for hearing loss in Cameroon. Identified genetic causes accounted for 14.8% (n = 86), putative environmental causes for 52.6% (n = 306) and unknown causes for 32.6% (n = 190). Amongst Genetic causes, the syndromic hearing loss accounted for 13.1% (n = 12) of cases, the rest being non syndromic (n = 74). Consanguineous families accounted for 5.7% (n = 33) of the whole sample, and 15.1% (n = 13) of genetic cases. No union between deaf parents was observed.ConclusionThese data highlight the possible predominance of putative environmental causes of childhood deafness in Cameroon, and emphasize the need for improved policies for prevention of infectious diseases and for neonatal hearing screening. However, further molecular analyses and targeted CT scan investigations are required to more accurately gauge the contribution of genetics etiologies.     

The Production of High Affinity Monoclonal Antibodies to Human Chorionic Gonadotropin and Their Application to Immunoradiometric Assay

Abstract

Production of monoclonal antibodies against hCG has been studied using hCG as the antigen. This study reports the successful isolation of hybrid clones secreting monoclonal antibodies specific for hCG with an affinity constant higher than 10¹⁰M^?l. Of 23 fusions, only 17 fusions have produced positive clones which secrete antibodies giving high levels of binding with ^l25I-labelled hCG in the supernatant. Finally, 6 different monoclonal antibodies have been isolated; 4 of them, specific for the β-subunit, with a Ka approximately 1.1–4.0 ± 10¹¹M^?1 and 2 others, specific for the α-subunit, presenting an affinity of 2.5 ± 10¹⁰M^?l. When the antibodies specific for the β-subunit are used, specific and highly sensitive radioim-munoassays are obtained after only 3 hrs of incubation. Using iodinated monoclonal antibodies specific for the α-subunit and tubes coated with antibodies against the β-subunit, we have developped sensitive immunoradiometric assays.     

Complex craniosynostosis is associated with the 2p15p16.1 microdeletion syndrome

In a screening project of patients with (complex) craniosynostosis using genomic arrays, we identified two patients with craniosynostosis and microcephaly with a deletion in the 2p15p16.1 chromosomal region. This region has been associated with a new microdeletion syndrome, for which patients have various features in common, including microcephaly and intellectual disability. Deletions were identified using Affymetrix 250K SNP array and further characterized by fluorescence in situ hybridization (FISH) analysis and qPCR. The deletions in our two patients overlapped within the 2p15p16.1 microdeletion syndrome area and were 6.8 and 6.9 Mb in size, respectively. FISH and qPCR confirmed the presence of only one copy in this region. Finemapping of the breakpoints indicated precise borders in our patients and were further finemapped in two other previously reported patients. Clinical features of patients with deletions in the 2p15p16.1 region vary. Including data from our patients, now eight out of nine reported patients have microcephaly, one of the major features, and all had intellectual disability. The current reported two patients add different forms of craniosynostosis to the clinical spectrum of this recently recognized microdeletion syndrome. © 2013 Wiley Periodicals, Inc.