Detection and characterisation of human astroviruses in children with acute gastroenteritis in Blantyre,Malawi

In a 2-year hospital-based study of paediatric gastroenteritis in Blantyre, Malawi, astroviruses were detected by enzyme immunoassay in 15 (1.9%) of 786 inpatients and in 9 (2.3%) of 400 outpatients. Greater disease severity was noted in children coinfected with human immunodeficiency virus (HIV). Six human astrovirus (HAstV) genotypes were identified, including HAstV-1 (25%), HAstV-2 (21%), HAstV-3 (25%), HAstV-4 (13%), HAstV-5 (4%), and HAstV-8 (13%). Although astroviruses are not major causes of gastroenteritis among children admitted to hospital in Blantyre, concomitant HIV infection appears to be a risk factor for increased severity of disease.     

Amino acid sequences of myosin essential and regulatory light chains from two clam species: Comparison with other molluscan myosin light chains

Summary We have determined the amino acid sequences of the essential light chains (ELC) and regulatory light chains (RLC) of myosin from two species of clam,Mercenaria mercenaria andMacrocallista nimbosa, using protein chemistry methods. The N-termini of all four proteins were blocked, and sequencing was carried out on various chemically and enzymatically produced peptide fragments. Cleavage of eitherMercenaria RLC (MRLC) orMacrocallista RLC (VLC) at its 3 Arg yielded four peptides, three of which could not be sequenced directly, due to an N-terminal blocking group and 2 Arg-Gln bonds in these proteins. The fourth peptide was partially and specifically cleaved at an unusually reactive residue, Met-64, which is invariant in all known RLC sequences. A comparison of all available molluscan ELC and RLC sequences was carried out in search of clues to functionally important features of these proteins in muscles which are regulated by a Ca²⁺-sensitive myosin. By analogy with other RLCs, VRLC and MRLC may be phosphorylated at Ser-11 by an endogenous kinase. All myosin light chains, like troponin C and calmodulin, contain four homologous regions, I to IV, each of which contains a twelve-residue potential Ca²⁺-binding loop flanked on either side by a pair of helices. All RLCs, including those from Ca²⁺-insensitive myosins, contain a divalent cation-binding site in region I. Clam and other molluscan ELCs contain a single Ca²⁺-binding site in region III. This site is present only in the ELCs of myosins that are regulated by direct binding of Ca²⁺. The ELC site III is likely to play a key role in the regulation of molluscan muscle contraction.     

Sexuality and people with intellectual disabilities: A historical perspective

Until the 1960s, the sexuality of people with mental retardation was handled by denial and suppression. The eugenics movement of 1880–1940 led to forced mass sterilization and the segregation of these members of our society. The civil rights movement and the sexual revolution were among the catalysts for change as was the move toward normalization and deinstitutionalization of people with mental retardation. In the last 25 years, parents and professionals have begun to work together to find ways to help mentally handicapped individuals to understand their sexuality and to engage in appropriate self-affirming sexual behaviors. We have established goals, guidelines, and curricula for sexuality education. We have trained parents and staff and developed policies for handling sensitive issues, such as sterilization and problematic sexual expression. The AIDS epidemic has provided new impetus for improving education and training in this emerging field.A.C.S.W.Private practice (as a consultant, lecturer, and trainer in sexuality and mental retardation).     

Detection of coronary disease patients at high risk for recurrent myocardial infarction by elevated plasma inactive creatine kinase B protein levels

The diagnostic and prognostic significance of plasma inactive creatine kinase B protein (CK-Bi) levels measured by radioimmunoassay was determined in various ischemic myocardial syndromes. In 120 stable angina patients free of pain at time of blood sampling, mean CK-Bi level was 114 ± 42 (SD) μg-equiv/ml; 195 μg-equiv/ml (95% confidence interval) represented upper limit of normal. In seven coronary artery disease (CAD) patients atrial pacing-induced ischemia was not associated with increased coronary sinus CK-Bi. Of 201 consecutive patients with suspected acute infarction (AMI), 45 developed ECG criteria of transmural AMI with concomitant increased plasma CK-Bi levels (498 ± 133, range 372–718 μg-equiv/ml). Elevated CK-Bi levels in evolving transmural AMI were detected before raised CK enzyme activity. Elevated plasma CK-Bi levels also occurred in acute pericarditis and in unstable angina. In the 84 patients not developing ECG changes or elevated plasma CK activity, their plasma CK-Bi levels were also normal and no coronary events occurred in the next 6 months. The remaining 55 patients had nontransmural AMI, with 15 also having elevated plasma CK and CK-Bi levels, of whom six developed re-AMI in the next 3 months. In the other 40 nontransmural AMI patients, plasma CK-Bi levels (350 ± 65 μg-equiv/ml, range 228 to 445) increased significantly without associated CK activity rise, and 24 developed re-AMI (three fatal) in the next 6 months. These data suggest that: (1) plasma CK-Bi protein radioimmunoassay measurement provides a sensitive means for detecting myocardial necrosis or inflammation and (2) elevated plasma CK-Bi levels in coronary disease patients during myocardial ischemic pain may afford identification of a CAD clinical subset at high risk of subsequent AMI.