A clinical and histological comparative study of the effect of nifedipine and phenytion on human gingiva

Ten patients manifesting gingival enlargement were chosen for this study. Five patients had been treated with 4 mg nifedipine per day as a treatment for angina pectoris, while the other five patients treated with phenytion as an anticonvulsant drug. Clinical and histological data showed that nefidipine induced gingival hyperplasia which is of close similarity to that induced by phenytion despite the differences in target tissue.     

Anemia severity and missed dialysis treatments in erythropoietin-treated hemodialysis patients

A comparative study was conducted of the results of venous end-to-end and end-to-side anastomosis in 948 clinical cases of microvascular free-tissue transfers for head and neck reconstruction following tumor resection. End-to-side anastomosis to the internal jugular vein was achieved uneventfully in the present series, while a variety of recipient veins was used for end-to-end anastomosis. The incidence of thrombosis was 1.8% (15/835) in the end-to-end anastomosis group and 2.7% (3/113) in end-to-side venous anastomosis. No statistical difference was observed between the two groups. One may hesitate to perform end-to-side anastomosis because of unfamiliarity, concern over technical difficulty, and unreliability. As a result of our statistical analysis, we are convinced that end-to-side anastomosis directly to the internal jugular vein, whenever available, is the preferred procedure in microvascular free-tissue transfers for reconstruction of the head and neck following tumor resection.     

Eliciting the views of experienced midwives about the assessment of competence in midwifery

OBJECTIVE: to investigate the views of the English National Board for Nursing, Midwifery and Health Visiting (ENB) Professional Midwifery Advisory Network (PMAN) members about the assessment of competence in midwifery. DESIGN: initial questionnaire followed by a group discussion of a summary of the data from the completed questionnaires. PARTICIPANTS: 54 PMAN midwives representing education, management, research, practice and supervision; plus six ENB Education Officers (midwifery). FINDINGS: the response rate to the questionnaires was 75%. In the group discussion the PMAN members commented particularly on: the large number of items identified as needing assessment in practice and by written work; lack of total agreement on the assessment in practice of normal delivery; differences in practitioners' perceptions of assessment; the number and range of areas to be assessed; differences in expectation of 'task' assessment versus 'holistic' assessment; lack of assessment in simulation; heavy reliance on written work in assessment. CONCLUSIONS: the group's discussion of the questionnaire data revealed further interesting data, which added considerably to the initial analysis and overview. Some participants had misinterpreted the instructions and found that what they had filled in did not accurately reflect their beliefs about assessment. General consensus was reached on the need for a national standard or framework for assessment and more emphasis to be placed on assessing students in the practice setting whilst ensuring this includes knowledge and understanding and not merely psycho-motor skills. The major implications include effective preparation of assessors and more teacher involvement in practice to support the midwife assessors.     

The identification of Mycoplasma mycoides mycoides LC as the aetiological agent of balanoposthitis and vulvovaginitis in sheep in South Africa

Clinical ulcerative balanoposthitis and vulvovaginitis was experimentally reproduced in 14 sheep infected with a Mycoplasma mycoides mycoides LC field strain, isolated from the Straussheim Dorper stud. The study encompassed a series of field observations, a therapeutic trial and experimental investigations. A wide range of bacteria and various mycoplasma spp., but no viruses, were isolated from a large number of infected animals.     

Phase I evaluation of zidovudine administered to infants exposed at birth to the human immunodeficiency virus

This study evaluated the safety, tolerability, and pharmacokinetics of zidovudine administered intravenously and orally to infants born to women infected with the human immunodeficiency virus. Thirty-two symptom-free infants were enrolled before 3 months of age. The pharmacokinetics of zidovudine were evaluated in each infant after single intravenously and orally administered doses of zidovudine on consecutive days, and during long-term oral administration of the drug for 4 to 6 weeks. As new patients were enrolled, doses of zidovudine were progressively increased from 2 to 4 mg/kg. Therapy was continued for up to 12 months in 7 of the infants proved to be infected with human immunodeficiency virus. Zidovudine was generally well tolerated; 20 children (62.5%) had anemia (hemoglobin level < 10.0 gm/dl) during therapy and 9 (28.1%) had neutropenia (neutrophil count < or = 750 cells/mm3); these hematologic abnormalities usually resolved spontaneously. The total body clearance of zidovudine increased significantly with age, from an average of 10.9 ml/min per kilogram in infants < or = 14 days of age to 19.0 ml/min per kilogram in older infants (p < 0.0001). Concurrently, there was a significant decrease in serum half-life from 3.12 hours in infants < or = 14 days to 1.87 hours in older infants (p = 0.0002). Oral absorption was satisfactory and bioavailability decreased significantly with age, from 89% in infants < or = 14 days to 61% in those > 14 days of age (p = 0.0002). Plasma concentrations of zidovudine were calculated to be in excess of 1 mumol/L (0.267 micrograms/ml) for 4.12 +/- 1.86 hours and 2.25 +/- 0.78 hours after oral doses of 2 mg/kg in infants younger than 2 weeks and 3 mg/kg in older infants, respectively. We conclude that zidovudine administered at oral doses of 2 mg/kg every 6 hours to infants aged less than 2 weeks and 3 mg/kg every 6 hours to infants older than 2 weeks resulted in plasma concentrations that are considered virustatic against human immunodeficiency virus. Zidovudine was well tolerated by infants at these doses.     

Identification and differential subcellular localization of the neuronal class C and class D L-type calcium channel alpha 1 subunits

To identify and localize the protein products of genes encoding distinct L-type calcium channels in central neurons, anti-peptide antibodies specific for the class C and class D alpha 1 subunits were produced. Anti-CNC1 directed against class C immunoprecipitated 75% of the L-type channels solubilized from rat cerebral cortex and hippocampus. Anti-CND1 directed against class D immunoprecipitated only 20% of the L-type calcium channels. Immunoblotting revealed two size forms of the class C L-type alpha 1 subunit, LC1 and LC2, and two size forms of the class D L-type alpha 1 subunit, LD1 and LD2. The larger isoforms had apparent molecular masses of approximately 200-210 kD while the smaller isoforms were 180-190 kD, as estimated from electrophoresis in gels polymerized from 5% acrylamide. Immunocytochemical studies using CNC1 and CND1 antibodies revealed that the alpha 1 subunits of both L-type calcium channel subtypes are localized mainly in neuronal cell bodies and proximal dendrites. Relatively dense labeling was observed at the base of major dendrites in many neurons. Staining in more distal dendritic regions was faint or undetectable with CND1, while a more significant level of staining of distal dendrites was observed with CNC1, particularly in the dentate gyrus and the CA2 and CA3 areas of the hippocampus. Class C calcium channels were concentrated in clusters, while class D calcium channels were generally distributed in the cell surface membrane of cell bodies and proximal dendrites. Our results demonstrate multiple size forms and differential localization of two subtypes of L-type calcium channels in the cell bodies and proximal dendrites of central neurons. The differential localization and multiple size forms may allow these two channel subtypes to participate in distinct aspects of electrical signal integration and intracellular calcium signaling in neuronal cell bodies. The preferential localization of these calcium channels in cell bodies and proximal dendrites implies their involvement in regulation of calcium-dependent functions occurring in those cellular compartments such as protein phosphorylation, enzyme activity, and gene expression.     

Mice lacking ataxin-1 display learning deficits and decreased hippocampal paired-pulse facilitation

Spinocerebellar ataxia type 1 (SCA1) is a neurodegenerative disorder characterized by ataxia, progressive motor deterioration, and loss of cerebellar Purkinje cells. To investigate SCA1 pathogenesis and to gain insight into the function of the SCA1 gene product ataxin-1, a novel protein without homology to previously described proteins, we generated mice with a targeted deletion in the murine Sca1 gene. Mice lacking ataxin-1 are viable, fertile, and do not show any evidence of ataxia or neurodegeneration. However, Sca1 null mice demonstrate decreased exploratory behavior, pronounced deficits in the spatial version of the Morris water maze test, and impaired performance on the rotating rod apparatus. Furthermore, neurophysiological studies performed in area CA1 of the hippocampus reveal decreased paired-pulse facilitation in Sca1 null mice, whereas long-term and post-tetanic potentiations are normal. These findings demonstrate that SCA1 is not caused by loss of function of ataxin-1 and point to the possible role of ataxin-1 in learning and memory.