Histological assessment of SJL/J mice treated with the antioxidants coenzyme Q10 and resveratrol.

The muscular dystrophies (MDs) are genetic disorders of muscle degeneration due to mutations in genes that encode a wide variety of proteins. Dysferlinopathy are characterized by the absence of dysferlin in skeletal muscle and an autosomal recessive mode of inheritance. Both histological and ultrastructural pathology have been well established in dysferlinopathy patients and dysferlin-deficient animal models. To our knowledge the effect of antioxidant supplementation on this level has not been described previously. This article therefore focuses on the histopathology to reveal the effect of antioxidant supplementation. The study aimed to determine, at cellular level, the histopathological changes in the SJL/J mouse model following a 90 day trial with antioxidant supplementation. Markedly reduced inflammatory insult in the more affected quadriceps muscles of animals treated with high doses of CoQ10 and a combination of resveratrol/CoQ10 were observed. The outcome provides evidence that high doses of antioxidant supplementation resulted in decreased dystrophic markers and enhanced tissue integrity at cellular level.

How we do it: patient participation in cochlear implant selection.

. Involving patients and parents in the choice of their cochlear implant encourages an active role in the process and facilitates 'bonding' and 'ownership' of the device. . The most frequent reasons given by patients for selecting a device included cochlear implant comfort and appearance. . We describe the Implant Programme based at the Royal National Throat, Nose and Ear Hospital, London, and also examine patient satisfaction with the scheme.

The South African stroke risk in general practice study.

BACKGROUND: Incidence of stroke is increasing in sub-Saharan Africa and stroke prevention is an essential component of successful stroke management. General practitioners (GPs) are well placed to manage stroke risk factors. To design appropriate strategies for risk factor reduction we need to know the risk factor prevalence in each of the population groups attending GPs. The aim of this study was to establish the prevalence of stroke risk factors in the South African general practice population. METHOD: We conducted a multicentre, observational study of patients attending general practice in South Africa. Two hundred general practices were randomly selected from lists provided by pharmaceutical representatives. Each GP approached 50 consecutive patients aged 30 years and older. Patients completed an information sheet and the GP documented the patient's risk factors. The resulting sample is relevant if not necessarily representative in a statistical sense. RESULTS: A total of 9 731 questionnaires were returned out of a possible 10,000. The mean age of particpants was 50.7 years. Seventy-six per cent had 1 or more risk factors and 40% had 2 or more risk factors. Hypertension was the commonest risk factor in all population groups (55%) but was highest in black patients (59%). Dyslipidaemia was commonest in whites (37%) and least common in blacks (5%). Diabetes was commonest in Asians (24%) but least common in whites (8%). Risk factors other than smoking increased with age. CONCLUSION: This study provides unique data on the prevalence of stroke risk factors in a South African general practice population. Risk factors are common in all population groups, but differ in distribution among the groups. There is considerable opportunity to reduce the burden of stroke in South Africa through GP screening for and treatment of risk factors.

VL position 34 is a key determinant for the engineering of stable antibodies with fast dissociation rates.

Predictive engineering of antibodies exhibiting fast kinetic properties could provide reagents for biotechnological applications such as continuous monitoring of compounds or affinity chromatography. Based on covariance analysis of murine germline antibody variable domains, we selected position L34 (Kabat numbering) for mutational studies. This position is located at the VL/VH interface, at the base of the paratope but with limited antigen contacts, thus making it an attractive position for mild alterations of antigen binding properties. We introduced a serine at position L34 in two different antibodies: Fab (fragment antigen binding) 57P (Asn34Ser) and scFv (single chain fragment variable) 1F4 (Gln34Ser), that recognize peptides derived from the coat protein of tobacco mosaic virus and the oncoprotein E6, respectively. Both mutated antibodies exhibited similar properties: (i) expression levels of active fragments in Escherichia coli were markedly improved; (ii) thermostability was enhanced; and (iii) dissociation rate parameters (k(off)) were increased by 2- and at least 57-fold for scFv1F4 and Fab57P, respectively, while their association rate parameters (k(on)) remained unchanged. The L34 Ala and Thr mutants of both antibody fragments did not possess these properties. This first demontration of similar effects observed in two antibodies with different specificities may open the way to the predictive design of molecules with enhanced stability and fast dissociation rates.

Self-protection against cell wall hydrolysis in Streptococcus milleri NMSCC 061 and analysis of the millericin B operon.

Streptococcus milleri NMSCC 061 produces an endopeptidase, millericin B, which hydrolyzes the peptide moiety of susceptible cell wall peptidoglycan. The nucleotide sequence of a 4.9-kb chromosomal region showed three open reading frames (ORFs) and a putative tRNA(Leu) sequence. The three ORFs encode a millericin B preprotein (MilB), a putative immunity protein (MilF), and a putative transporter protein (MilT). The milB gene encodes a 277-amino-acid preprotein with an 18-amino-acid signal peptide with a consensus IIGG cleavage motif. The predicted protein encoded by milT is homologous to ABC (ATP-binding cassette) transporters of several bacteriocin systems and to proteins implicated in the signal-sequence-independent export of Escherichia coli hemolysin A. These similarities strongly suggest that the milT gene product is involved in the translocation of millericin B. The gene milF encodes a protein of 302 amino acids that shows similarities to the FemA and FemB proteins of Staphylococcus aureus, which are involved in the addition of glycine to a pentapeptide peptidoglycan precursor. Comparisons of the cell wall mucopeptide of S. milleri NMSCC 061(resistant to lysis by millericin B) and S. milleri NMSCC 051(sensitive) showed a single amino acid difference. Serial growth of S. milleri NMSCC 051 in a cell wall minimal medium containing an increased concentration of leucine resulted in the in vivo substitution of leucine for threonine in the mucopeptide of the cell wall. A cell wall variant of S. milleri NMSCC 051 (sensitive) that contained an amino acid substitution (leucine for threonine) within its peptidoglycan cross bridge showed partial susceptibility to millericin B. The putative tRNA(Leu) sequence located upstream of milB may be a cell wall-specific tRNA and could together with the milF protein, play a potential role in the addition of leucine to the pentapeptide peptidoglycan precursor and thereby, contributing to self-protection to millericin B in the producer strain.

Absence of a putative mannose-specific phosphotransferase system enzyme IIAB component in a leucocin A-resistant strain of Listeria monocytogenes, as shown by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Leucocin A is a class IIa bacteriocin produced by Leuconostoc spp. that has previously been shown to inhibit the growth of Listeria monocytogenes. A spontaneous resistant mutant of L. monocytogenes was isolated and found to be resistant to leucocin A at levels in excess of 2 mg/ml. The mutant showed no significant cross-resistance to nontype IIa bacteriocins including nisaplin and ESF1-7GR. However, there were no inhibition zones found on a lawn of the mutant when challenged with an extract containing 51,200 AU of pediocin PA-2 per ml as determined by a simultaneous assay on the sensitive wild-type strain. DNA and protein analysis of the resistant and susceptible strains were carried out using silver-stained amplified fragment length polymorphism (ssAFLP) and one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Two-dimensional SDS-PAGE clearly showed a 35-kDa protein which was present in the sensitive but absent from the resistant strain. The N-terminal end of the 35-kDa protein was sequenced and found to have an 83% homology to the mannose-specific phosphotransferase system enzyme IIAB of Streptococcus salivarius.

Purification and partial characterization of a murein hydrolase, millericin B, produced by Streptococcus milleri NMSCC 061.

Streptococcus milleri NMSCC 061 was screened for antimicrobial substances and shown to produce a bacteriolytic cell wall hydrolase, termed millericin B. The enzyme was purified to homogeneity by a four-step purification procedure that consisted of ammonium sulfate precipitation followed by gel filtration, ultrafiltration, and ion-exchange chromatography. The yield following ion-exchange chromatography was 6.4%, with a greater-than-2,000-fold increase in specific activity. The molecular weight of the enzyme was 28,924 as determined by electrospray mass spectrometry. The amino acid sequences of both the N terminus of the enzyme (NH(2) SENDFSLAMVSN) and an internal fragment which was generated by cyanogen bromide cleavage (NH(2) SIQTNAPWGL) were determined by automated Edman degradation. Millericin B displayed a broad spectrum of activity against gram-positive bacteria but was not active against Bacillus subtilis W23 or Escherichia coli ATCC 486 or against the producer strain itself. N-Dinitrophenyl derivatization and hydrazine hydrolysis of free amino and free carboxyl groups liberated from peptidoglycan digested with millericin B followed by thin-layer chromatography showed millericin B to be an endopeptidase with multiple activities. It cleaves the stem peptide at the N terminus of glutamic acid as well as the N terminus of the last residue in the interpeptide cross-link of susceptible strains.

[Job satisfaction in nursing]. / Werksbevrediging in verpleging.

Job satisfaction is a relative term that mean different things to different people. Although money was always considered to be the prime motivator of staff, it is only one factor that contribute towards job satisfaction. Other factors include aspects such as available time for personal activities, a need to be involved in decision-making and the right to be informed, to name but a few. Motivation as a tool to ensure a satisfied worker score include strategies, e.g., open communication channels, a better working environment, staff development and managerial leadership.