Myeloid bodies in the pigment epithelium of a teleost embryo, the viviparous Poecilia reticulata

Appearance of myeloid bodies (MB) in the retinal pigment epithelium (RPE) precedes photoreceptor outer segment development in Poecilia reticulata embryos reared under a 12 hrs LD cycle, in constant darkness (DD) and constant light (LL). When first formed, MB are predominantly continuous with rough endoplasmic reticulum (RER). The same is observed in the peripheral growth zone of the developed eye, whereas in differentiated parts, MB are continuous with the smooth endoplasmic reticulum (SER). At onset of photomechanical movements, wavy MB predominate in light-adapted LD embryos, are exclusively present in LL and are located in the RPE processes. SER abounds. Straight MB predominate in dark-adapted LD embryos, are exclusively present in DD and contain electrondense material between lamellae. Diurnal appearance of electrondense material may be coupled with transfer of retinol, mediated by various transport proteins.     

Reduction of Endotoxin Levels in Influenza Virus Vaccines by Barium Sulfate Adsorption-Elution

The level of endotoxin in influenza virus vaccine lots was reduced 10- to 20-fold after barium sulfate adsorption-elution. The amount of viral antigen lost was negligible.     

Mutants of Escherichia coli Sensitive to Antibiotics

Mutants of Escherichia coli sensitive to the antibiotic synergistin A, an inhibitor of protein synthesis, were isolated. These mutants were pleiotropic, being also sensitive to a large number of unrelated antibiotics and to lysis by detergents. These pleiotropic responses indicated that the mutations affected cell wall or membrane synthesis. Consequently, selection for antibiotic-sensitive mutants constitutes a useful means for isolating cell wall or membrane mutants.     

CloneSeq: A highly sensitive analysis platform for the characterization of 3D-cultured single-cell-derived clones

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The elimination of herpes simplex plaques by antibody and the emergence of resistant strains.

Established type 1 HSV plaques were eliminated by antibody. Antibody had to remain in contact with infected cells for several days to have a maxi;mum effect. It did not prevent the production of viral induced antigens in a cell when applied after the cell was infected but did prevent the transmission of infection to contiguous cells. Strains which were resistant to elimination by antibody formed syncytia, did not grow to significantly higher titers than nonresistant strains, and were as easily neutralized by antiserum as nonresistant strains.     

Obstetric accidents: a review of 64 cases.

OBJECTIVE--To identify the causes of obstetric accidents. DESIGN AND SETTING--Analysis of case records at the Medical Protection Society''s London office covering the five years 1982-6. SUBJECTS--Cases that had come to litigation which had resulted in stillbirth, perinatal or neonatal death, central nervous system damage to the baby, or maternal death and in which there was an opinion from a senior obstetrician consulted by the society. Of 147 cases reviewed, 64 met the criteria for the study. MAIN OUTCOME MEASURES--The principal findings of the expert reviewers. RESULTS--Three major topics of concern emerged common to most of the 64 cases. These were inadequate fetal heart monitoring, mismanagement of forceps, and inadequate supervision by senior staff. In 11 of the 64 cases cardiotocography was omitted, in 19 cases the trace was missing, in six cases the trace was unreadable, and in 14 of the remaining 28 cases signs of fetal distress went unnoticed or were ignored. In 31 cases forceps were used to aid delivery or were tried and abandoned in favour of caesarean section. In 16 cases two or more attempts to use forceps were made. Five infant deaths were directly attributed to mismanaged forceps. In 20 cases senior staff were criticised by the expert reviewer for failure to come to the labour ward. In many of these cases they may have given advice over the telephone, but the inadequacy of records made it impossible to tell. In these cases the labour and birth were managed by junior staff, usually a senior house officer. In six cases when senior staff did come they suggested that no action was needed. CONCLUSION--These few cases should not be dismissed as isolated incidents in obstetric practice in Britain. They reflect more general problems--namely, concerning the ability of junior doctors to interpret fetal heart traces accurately, their ability to use forceps, and the participation of senior staff in running a labour ward and delivery suite.