Sources of influence on infant feeding practices in Hong Kong

The breastfeeding rate in Hong Kong is low compared to the rates in Western countries. To understand the relative importance of different sources of influence on infant feeding practices, 714 Chinese mothers with infants aged 4 weeks to 6 months were studied. It was found that the bottlefeeding mothers were influenced more by the medical professionals who did not support breastfeeding. This influence was further reinforced by the mass media and particularly television advertisements on infant formulae. The successful breastfeeding mothers, on the other hand, were influenced more by their social networks through which they were told of the dangers of bottlefeeding. The failed breastfeeding mothers differed from the other groups in the lack of support they experienced from friends and relatives. Although they received professional encouragement to breastfeed, they were more sheltered from the influence of mass media and social networks. From these findings, it is suggested that different sources of influence are related to different feeding practices. However, to be able to continue with the practice that one has chosen, the availability of social support is essential. Implications of these findings are discussed and several recommendations to promote breastfeeding are made.

Solid-sphere test for examination of anal sphincter strength

The solid-sphere test was used to measure the strength of the anal sphincter. A plastic sphere 2 cm in diameter was inserted into the rectum. The plastic sphere was stepwise loaded. The patient was asked to contract his sphincter and try to keep the sphere inside the rectum. The maximal strength was defined as the force needed to draw the sphere through the anus. In continent persons the force needed was above 7 N, in persons with partial incontinence between 5 and 7 N, and in persons with total incontinence below 5 N. A clear difference between continent and totally incontinent persons was found. The solid-sphere test is simple, cheap, and of great value in examination of faecal incontinence.

A controlled trial of a plastic wound ring drape to prevent contamination and infection in colorectal surgery

A controlled, randomized study of the efficacy of a plastic wound ring drape (Opdrape, Triplus) to prevent contamination and infection in elective colorectal operations is reported. Seventy patients were operated upon with the wound ring drape and 70 patients without. All patients received preoperative systemic antibiotic prophylaxis. Abdominal wound infection was observed in seven of 70 (10 per cent) patients with the wound ring drape and six of 70 (9 per cent) without (N.S.). An operative swab for bacteriologic evaluation was obtained from 85 per cent of the wounds. There was no evidence that the drape protected the wound from contamination with intestinal bacterial flora. It was concluded that the wound ring drape prevents neither contamination nor infection.

The (Na,K)-ATPase of Friend erythroleukemia cells is phosphorylated near the ATP hydrolysis by an endogenous membrane-bound kinase

Friend murine erythroleukemia cells (MEL cells) contain a cAMP-independent protein kinase which phosphorylates the 100,000-Da catalytic subunit of the (Na,K)-ATPase both in living cells and in the purified plasma membrane (Yeh, L.-A., Ling, L., English, L., and Cantley, L. (1983) J. Biol. Chem. 258, 6567-6574). We have taken advantage of the selective phosphorylation of the 100,000-Da subunit in purified plasma membranes and the similarity between the proteolysis patterns of the MEL cell and dog kidney (Na,K)-ATPase to map the site of kinase phosphorylation on the MEL cell enzyme. The chymotryptic and tryptic cleavage sites of the dog kidney (Na,K)-ATPase have previously been located (Castro, J., and Farley, R. A. (1979) J. Biol. Chem. 254, 2221-2228). The 100,000-Da catalytic subunits of the dog kidney and MEL cell enzymes were specifically labeled at the active site aspartate residue by incubation with (32P)orthophosphate in the presence of Mg2+ and ouabain. Digestion of these two enzymes with chymotrypsin or trypsin revealed similar active site aspartate containing proteolytic fragments indicating a similar structure for the two enzymes. Chymotryptic digestions of MEL cell (Na,K)-ATPase labeled in vitro with [gamma-32P]ATP localize the region of kinase phosphorylation to within a 35,000-Da peptide derived from the middle of the 100,000-Da subunit. Tryptic digestion of the MEL cell plasma membranes degraded the 100,000-Da subunit to an NH2-terminal 43,000-Da peptide which contained the active site aspartate but which did not contain the kinase-labeled region. These results further locate the region of kinase phosphorylation to the COOH-terminal half of the 35,000-Da chymotryptic peptide. This location places the site of phosphorylation between the active site aspartate residue which accepts the phosphate of ATP during turnover and an ATP-binding site which has previously been located by labeling with fluorescein 5'-isothiocyanate (Carilli, C. T., Farley, R. A., Perlman, D. M., and Cantley, L. C. (1982) J. Biol. Chem. 257, 5601-5606). Phosphorylation of the (Na,K)-ATPase in this region may serve to regulate the activity of this enzyme.

Recovering the parameters of finite mixtures of normal distributions from a noisy record: an empirical comparison of different estimating procedures

Three procedures were compared for their ability to estimate the known parameters of mixtures of normal distributions: maximum likelihood estimators (MLE), X2 minimization method and the least-square error procedure. For this purpose a Monte-Carlo study was undertaken to evaluate empirically the performance of the estimators. We chose to investigate their behaviour using closely-positioned mixtures of two or 3 univariate Gaussians. The Monte-Carlo simulations clearly demonstrate the superiority of the MLE and X2 minimum methods. Other reasons why the MLE is to be preferred are discussed. The effect of sample size was also examined. All 3 estimators have also been applied to data derived from different physiological experiments, and the use of the estimators is considered in practical terms. The formulae for all 3 procedures are given in the Appendix.

Phosphorylation of the (Na,K)-ATPase by a plasma membrane-bound protein kinase in friend erythroleukemia cells

A decrease in the activity of the (Na,K)-ATPase is an early and essential step in commitment of Friend virus-infected murine erythroleukemia cells to terminal erythroid differentiation. Plasma membranes from these cells were purified and shown to contain ouabain-inhibitable (Na,K)-ATPase present as approximately 0.4% of the total membrane protein. Protein kinase activity also co-purified with the plasma membrane and preferentially phosphorylated a Nonidet P-40 detergent-extractable 100,000-Da peptide. The 100,000-Da phosphopeptide migrated with the alpha subunit of dog kidney (Na,K)-ATPase when electrophoresis was carried out in the presence of sodium dodecyl sulfate in either 5 or 10% polyacrylamide gels. In two-dimensional gel electrophoresis, it separated into a series of spots between pH 5.1 and 5.4, while dog kidney alpha subunit appeared as a doublet at pH 5.3-5.4. When Nonidet P-40-solubilized plasma membranes were passed through a ouabain affinity column in the presence of Mg2+, Na+, and ATP, the 100,000-Da phosphopeptide was retained and could be eluted by ouabain. This peptide was also phosphorylated in living murine erythroleukemia cells, and proteolysis patterns of the peptide labeled in vitro, the peptide labeled in vivo, and the purified dog kidney alpha subunit using V8 protease were nearly identical. Phosphothreonine was detected in both the peptides labeled in vivo and in vitro.

Enhanced resistance of mice to Mycoplasma pulmonis-induced arthritis by administration of killed Corynebacterium parvum

Inoculation of mice with Corynebacterium parvum 14 days before intraperitoneal inoculation of Mycoplasma pulmonis resulted in arthritis of significantly lesser magnitude than in control mice as measured both clinically and histologically. Mycoplasmas were isolated from the joints of mice inoculated with C. parvum less frequently than from control mice when the arthritis was maximal. Mycoplasmas were also isolated in smaller numbers from the blood and joints of mice pretreated with C. parvum within 2 hr after M. pulmonis inoculation. Complement-fixing antibody to M. pulmonis did not account for the differences observed. C. parvum given during an established mycoplasmal infection, although capable of enhancing elimination of M. pulmonis from the joints of infected mice, had no effect upon the arthritis as measured clinically or histologically. The results provide evidence that immunomodulators such as C. parvum are capable of enhancing elimination of mycoplasmas from the joints of infected mice prior to or after the induction of arthritis.

Role of viable mycoplasmas in the pathogenesis of arthritis induced by M. pulmonis

The role of viable M. pulmonis organism in the pathogenesis of both the acute and chronic phases of M. pulmonis-induced arthritis was examined. In the acute phase of the arthritis most clinically involved joints contained organisms and the degree of clinical arthritis in a given joint correlated with the number of organisms isolated. The more severe the acute arthritis, the more frequently the M. pulmonis organism was isolated from the joints during the chronic phase. In the chronic phase, arthritis defined histologically correlated with the presence of M. pulmonis organisms within a given joint. No correlation was observed between clinical arthritis during the chronic phase and histopathology or the presence of M. pulmonis organisms within the joint. In chronically infected mice, M. pulmonis was isolated from the joints only but not from the blood, liver, spleen, lung or kidney of any mouse examined. The results support the concept that viable organisms play an essential role in the pathogenesis of the acute and chronic phases of M. pulmonis-induced arthritis in mice.

Effect of T-cell deficiency on the chronicity of arthritis induced in mice by Mycoplasma pulmonis

Mycoplasma pulmonis inoculated parenterally into athymic nude mice congenitally deficient in T cells caused a chronic arthritis of significantly greater magnitude than in immunologically normal mice. During the chronic phase of arthritis, M. pulmonis organisms were isolated from the joints and spleens of athymic nude mice more frequently and in larger numbers than from immunologically normal mice. The results support the concept that impaired T-cell function predisposes the mice to a severe degree of chronic arthritis as a result of their failure to eliminate the causative organisms.

Problems in the care of the infant diabetic patient

The unique problems of three infants who developed diabetes mellitus at 13 months of age or younger are discussed. These problems include: the administration of small doses of insulin; the difficulty in attaining control; and the evaluation of urinary sugar content. Suggestions for care are made.

Tumours of the testis. A report of 128 cases

The records of 128 patients treated between 1960 and 1971 at the University Hospital, Lund, because of tumour of the testis were analysed in respect of age at onset of the tumour, symptoms, histology, diagnosis, treatment and survival rate. Teratoma occured in 67 cases, in the majority at the age of 20-30 years. Treatment consisted in orchiectomy, lymphadenectomy, administration of cytostatics and radiation alone or combined, depending upon the histology and spread of the tumour. The 5-year survival rate was 40%. Sixty-one patients had seminoma, most of which appeared between 30 and 40 years of age. The patients were treated with orchiectomy and radiation. The 5-year survival rate was 82%.