Management development

This paper is the account of one area health authority's attempt to give its managers some positive help with their own, and their subordinates', development and to provide a focus for the discussion of ideas on the development of the organisation. The last three years have seen an attempt to conceive and give birth to a management development philosophy which despite its hybrid nature (being the product of both theory and circumstances) seems to meet the needs of one health authority.

The effects of copper and nitrogen supply on the distribution of copper in dissected wheat grains

The distribution of copper between the embryo and the endosperm was studied in the grain of two wheat cultivars (Gamenya and Petit Rojo) grown at marginal and sufficient copper and two levels of nitrogen. Copper concentration in whole grain increased markedly with copper level but differed little with nitrogen level. The dry weight and copper content of the embryo expressed as a proportion of the whole grain varied little among treatments, so that copper concentration in the embryo responded to treatment in a similar way to copper concentration in the whole grain. Copper concentrations in the embryo were at least 2.5 times as high as in the endosperm or whole grain at all levels of copper and nitrogen. It is suggested that where copper deficiency decreases grain number without decreasing the weight of individual grains the copper concentration in the mature whole grain, or in the embryo, is not causally related to grain development, and may be a poor indicator of the potential response of grain yield to copper application.

The effects of copper and nitrogen supply on the retranslocation of copper in four cultivars of wheat

The retranslocation of copper and nitrogen was studied in four cultivars of wheat grown in pots of a copper-deficient sand from Lancelin, W.A. Plants were grown at two levels of nitrogen and three levels of copper, and harvested three times during growth and at maturity. Plants grown at low copper were severely copper-deficient and yielded no grain. At low nitrogen, plants at marginal copper gave similar grain yields to plants at high copper. Application of high nitrogen at marginal copper either had little effect or depressed grain yield. Application of high nitrogen at high copper gave a strong positive interaction producing maximal grain yield in each cultivar. Low copper supply delayed yellowing and the decline in copper and nitrogen content of the oldest leaf of each cultivar. Application of high nitrogen further delayed yellowing of the oldest leaf and loss of its copper and nitrogen. Probably the copper content of the oldest leaf does not decline until the leaf begins to senesce. Senesced leaves retain low concentrations of copper and nitrogen. It is suggested that at marginal copper, copper retention by senesced vegetation limits the retranslocation of copper from vegetation to grain. Susceptibility to copper deficiency differed markedly with stage of growth and with cultivar. At marginal copper and high nitrogen, copper deficiency almost eliminated the grain yield of Argentine IX, but had relatively small effects on Gamenya, Olympic, and Petit Rojo. The higher susceptibility of grain production in Argentine IX to copper deficiency was not related to its copper content in whole tops or to its grain protein concentration. The susceptibility may have resulted from the ability of this cultivar to form large numbers of tillers which competed with the developing grain for retranslocated copper.

Carbon fiber-reinforced carbon as a potential implant material

A carbon fiber-reinforced carbon is being evaluated as a promising implant material. In a unidirectional composite, high strengths (1200 MN/m2 longitudinal flexural strength) and high modulus (140 GN/m2 flexural modulus) may be obtained with an interlaminar shear strength of 18 MN/m2. Alternatively, layers of fibers may be laid in two directions to give more isotopic properties. The compatibility of the material with bone has been studied by implanting specimens in holes drilled in rat femora. For a period of up to 8 weeks, a thin layer of fibrous tissue bridged the gap between bone and implant; but this tissue mineralizes and by 10 weeks, bone can be observed adjacent to the implant, giving firm fixation. Potential applications include endosseous dental implants where a greater strength in the neck than that provided by unreinforced carbon would be advantageous.

Physiological properties of the penis retractor muscle of Aplysia

The properties of the penis retractor muscle of Aplysia have been studied using intracellular, sucrose gap and tension recording. The fibers are of the invertebrate smooth muscle type and exhibit slow contractions which occur spontaneously or in response to stretch in isolated preparations. Individual muscle fibers are innervated by excitatory and inhibitory axons. A variety of sizes of excitatory and inhibitory junctional potentials can be recorded from them. The innervation is probably diffuse and functionally polyneuronal. The fibers are electrically coupled, permeable to potassium and chloride at rest, and exhibit no overshooting active responses. The muscle shows graded responses of depolarization and contraction proportional to strength of nerve stimulation. Facilitation and depression of junctional potentials are seen with various frequencies of nerve stimulation. Post-tetanic potentiation occurs with nerve stimulation at frequencies from 2 to 50 Hz and is suppressed in the presence of increased extracellular calcium concentrations.

Diffusion of antibiotics from acrylic bone-cement in vitro

The diffusion of Fucidin, gentamicin, and clindamycin from acrylic cement was tested in an in vitro system. The activity of Fucidin was very short-lived and only against gram-positive organisms; gentamicin inhibited gram-positive and gram-negative organisms for twenty-two and eleven days respectively; clindamycin had significant action only against gram-positive organisms and retained some activity for fifty-six days. We suggest that the destruction of organisms in the tissues is more likely to be achieved by topical and intravenous administration of antibiotics during the operation than by incorporation of antibiotic in the cement.

Purification and properties of streptococcal hyaluronate lyase

Hyaluronate lyase (hyaluronidase) has been purified and characterized from a group A type 4 Streptococcus. Production of the enzyme was favored by growth in trypsinized veal infusion in the presence of hyaluronate oligosaccharide and tetrasaccharide. Detectable enzymatic activity was diminished in the presence of N-acetylglucosamine and glucuronic acid. Purification of hyaluronate lyase consisted of 40 to 60% ammonium sulfate precipitation, diethylaminoethyl A-50 Sephadex ion-exchange chromatography, gel filtration with G-200 Sephadex, and adsorption to Sepharose 6B. Purified enzyme was antigenically homogeneous and free of proteinase, deoxyribonuclease, streptolysin 0, and streptokinase. Active hyaluronate lyase was recovered from neutral polyacrylamide gels, and it appeared to be a glycoprotein. A single band was detected by sodium dodecyl sulfate-acrylamide electrophoresis, which had a molecular weight of approximately 50,000. A molecular weight of 70,000 was observed by gel filtration. The purified enzyme had a Km of 3.8 x 10(-4) and a pH optimum of 6.0. Reducing agents increased the activity of crude enzyme at least threefold and were necessary to prevent inactivation of the purified enzyme.

Laboratory and clinical evaluation of tobramycin, a new aminoglycoside antibiotic

The in vitro susceptibility to tobramycin of 1,466 bacterial isolates, including several genera and strains of common pathogenic gram-negative bacilli and Staphylococcus aureus, was determined by conventional serial dilution methods. Tobramycin exhibited marked in vitro antibacterial activity; almost all of the isolates tested were inhibited by less than or equal to 2.5 mug of the drug/ml. The antibiotic was used in the treatment of several types of infection in 29 patients with normal renal function. Observations were made on the therapeutic and secondary effects of the drug and on possible toxicity to the eighth cranial nerve. Clinical therapeutic results were satisfactory, The hearing of one patient was impaired, but the relation of this effect to tobramycin therapy is uncertain. Serum levels of the antibiotic were measured in 10 patients to investigate whether the drug accumulated during repeated administration. Mean serum levels of tobramycin 1 hr after intramuscular injection of 1.0 mg/kg were between 2.5 and 3.0 mug/ml on days 1, 3, and 6 of therapy. No accumulation of the antibiotic was observed after repeated administration.

An unusual complication of minidose heparin therapy

A 50-year-old woman developed a massive hematoma of the superficial abdominal wall following subcutaneous heparin therapy. The lesion was located above the fasica, became infected, and was associated with epithelial necrosis over the right lower quadrant of the abdominal wall. Operative excision of the entire affected area with primary closure was successful 4 weeks following the injection. The etiology of this problem was attributed to accidental laceration of the superficial epigastric vessels. This extensive local complication of subcutaneous minidose heparin injection seems not to have been previously reported.

Paroxysmal nocturanal hemoglobinuria and marrow failure treated by infusion of marrow from an identical twin

An 18-year-old white Canadian male patient with paroxysmal nocturnal hemoglobinuria and refractory marrow failure received a marrow infusion from his normal identical twin brother without prior ablation of the patient's marrow by drugs or irradiation. After 2 years of follow-up, the patient is well with no evidence of clinical disease or significant hematological abnormality. The results suggest that normal marrow stem cells can have a selective advantage over the abnormal paroxysmall nocturnal hemoglobinuria clone.

A simple technique for obtaining Pap smears of the esophagus

A simple method for obtaining Papanicolaou smears of the esophagus is described. The procedure is easy to perform, does not require specialized equipment, and is a useful adjuvant to direct esophageal biospy.

Failure of carbon monoxide to induce myocardial infarction in cholesterol-fed cynomolgus monkeys (Macaca fascicularis)

Twenty-six adult female cynomolgus monkeys (Macaca fascicularis) were randomly assigned to four groups which were fed on a standard laboratory diet or a semipurified diet containing cholesterol. In two of the groups, the monkeys were exposed intermittently to CO throughout the day for 14 months; the control animals breathed room air. No myocardial infarctions were observed, and the ECG showed a transitory injury current in only one animal. No differences in plasma cholesterol levels or in aortic and coronary atherosclerosis could be attributed to CO exposure.