Effect of glycaemic control and duration of disease on overnight albumin excretion in diabetic children.

Urine albumin excretion rates were measured in overnight timed samples from diabetic and non-diabetic schoolchildren. The excretion rates in the diabetics were significantly higher than those in the controls and were positively correlated with age, duration of diabetes, and glycaemic control. Diabetic children aged 12 years and older had significantly higher albumin excretion rates than younger diabetic children matched for duration of disease. Among the non-diabetic controls there was no correlation between albumin excretion rate and age and the girls excreted significantly more albumin than the boys. Measurement of the overnight albumin excretion rate may provide a useful early indicator of the progression to clinical proteinuria in diabetes and is free from random variations such as that due to exercise.     

Characterization of some isolates of newly recovered avian sarcoma virus.

We previously reported the isolation of a newly recovered avian sarcoma virus (rASV) from tumors of chickens injected with transformation-defective (td) mutants of the Schmidt-Ruppin strain of Rous sarcoma virus (SR-RSV). In this paper, we present further biological and biochemical characterization of the recovered sarcoma viruses. High titers of rASV's were generally obtained by cocultivation of tumor cells with normal chicken embryo fibroblasts or by homogenization of tumor tissues. Most rASV isolates were similar to SR-RSV, subgroup A (SR-RSV-A), in their growth characteristics and were nondefective in replication. The subgroup specificity of rASV's and the electrophoretic mobilities of their structural proteins were the same as those parental td viruses. The nondefectiveness of rASV's was further substantiated by the size of their genomic RNA, which was indistinguishable from that of SR-RSV-A and substantially larger than that of parental td RNA. Molecular hybridization using complementary DNA specific to the src gene of SR-RSV (cDNAsrc) showed that the RNAs of td mutants used in this study contained extensive deletions within the src gene (7 to 30% hybridization with cDNAsrc); the same probe hybridized up to 90% with RNA from two isolates of rASV. These data indicate that rASV has regained genetic information which had been deleted in the td mutants and strongly suggest that the generation of rASV involves a genetic interaction between td virus and host cell genetic information.     

Decline in rate of death from ischaemic heart disease in the United Kingdom.

The rates of death from ischaemic heart disease in the United Kingdom in the years after 1968 were studied to establish whether any general trend had occurred. A decline in the rates began after 1973-4, was greatest in those aged 35-44 years, and occurred among both men and women and in each of the regions of England and in Wales and Scotland. Total dietary fat intake had started to fall about five years earlier, and this may provide part of the explanation. Changes in smoking habits also occurred but were more difficult to relate to the pattern of change in the death rates. If a general decline in ischaemic heart disease has begun in the United Kingdom a case may be made for close monitoring of changes in lifestyle and medical practice in different demographic groups to try to find the explanation.     

Rapid high-performance liquid chromatographic assay for total homocysteine levels in human serum

A rapid, isocratic high-performance liquid chromatographic (HPLC) method is described for the determination of total homocysteine levels in human serum. Prior to reversed-phase HPLC analysis, the serum thiols were derivatized with SBD-F (ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulphonate), a thiol-specific fluorogenic probe which is commercially available. Retention of SBD-homocysteine was sensitive to pH, and a mobile phase pH of 2.1 ensured baseline separation of serum thiols within 6 min. The method is simple, sensitive, reproducible (between-run coefficient of variation of 6.6%) and very suitable for routine determination of serum homocysteine levels in a clinical pathology laboratory.     

Avian erythroblastosis virus produces two mRNA''s.

We analyzed the viral mRNA's present in fibroblast nonproducer clones transformed by avian erythroblastosis virus. Two size classes of mRNA (28 to 30S and 22 to 24S) were identified by solution hybridization with both complementary DNA strong stop and complementary DNA made against the unique sequences of avian erythroblastosis virus. Based upon the kinetics of hybridization with complementary DNA made against the unique sequences of avian erythroblastosis virus, we estimated that there were 400 to 500 copies of the 28 to 30S RNA per cell and 200 to 250 copies of the 22 to 24S RNA per cell. Both RNA species were packaged in the virion. In vitro translation of the 28 to 30S virion RNA yielded a 75,000-dalton protein which was the 75,000-dalton gag-related polyprotein found in avian erythroblastosis virus-transformed cells. In vitro translation of the 22 to 24S virion RNA yielded two proteins (46,000 and 48,000 daltons). This indicates that there may be two genes in avian erythroblastosis virus, one coding for the 75,000-dalton gag-related polyprotein and the second coding for the 46,000- or 48,000-dalton protein or both.     

Ultrastructure of bacteria and the proportion of Gram-negative bacteria in marine sediments

Bacteria in sediments from the surface aerobic layer (0–1 cm) and a deeper anaerobic layer (20–21 cm) of a seagrass bed were examined in section by transmission electron microscopy. Bacteria with a Gram-negative ultrastructure made up 90% of bacteria in the surface layer, and Gram-positive bacteria comprised 10%. In the anaerobic zone, Gram-negative bacteria comprised 70% and Gram-positive bacteria 30% of the bacterial population. These differences were highly significant and support predictions of these proportions made from muramic acid measurements and direct counting with fluorescence microscopy. Most cells were enveloped in extracellular slime layers or envelopes, some with considerable structural complexity. The trophic value to animals of these envelopes is discussed. A unique organism with spines was observed.     

Calicotyle australiensis n. sp. and Calicotyle sp. (Monogenea,Monopisthocotylea) from the rectum and rectal glands,and Rugogaster hydrolagi Schell, 1973 (Trematoda,Aspidogastrea) from the rectal glands of holocephalans off the coast of southeastern Australia

Calicotyle australiensis n. sp. from Chimaera sp., caught off the coast of New South Wales, is described. It differs from the other species of the genus in the combination of the following characteristics: length of the penis-tube, absence of medial diverticula of the caeca and presence of hamuli. Calicotyle sp. from Rhinochimaera pacifica and Rugogaster hydrolagi from Chimaera sp. caught at the same locality are reported and illustrated.     

Isotocinergic neurons in the goldfish hypothalamus: Physiological and morphological studies on chemically identified cells

Summary Isotocinergic (IT) neurons show physiological and morphological characteristics that are similar to those of other preoptic neuroendocrine cells in the goldfish. Preoptic IT cells show resting membrane potentials of 20–55 mV, action potentials of up to 100mV, and physiological evidence of axonal branching. Dye-marked IT cells measure 14–56 m, their dendrites projecting to the ependyma and into the hypothalamic neuropil, their multiple beaded axons projecting to the pituitary. Indirect immunofluorescence identifies these dyemarked cells as IT. By combining electrophysiological, dye-marking and immunocytochemical techniques we can now, for the first time, study single, antidromically-identified peptidergic neurons of a specific type in vertebrate and invertebrate species.Supported by Grants from the USPHS (NS-13411 and NS-05696)The authors wish to thank Ms. S. Curtis for editorial assistance, Ms. D. Cronce for skillful technical assistance, Dr. W.W. Stewart for helpful suggestions and for his generous gift of Lucifer Yellow-CH, Dr. M. Manning for his generous gift of high quality peptides, and Dr. R.R. Dries and J.D. Fernstrom for kindly supplying antisera     

Immunocytochemical identification of vasopressinergic and oxytocinergic neurons in the hypothalamus of the cat

Our immunocytochemical investigation of the magnocellular neuroendocrine cells in the cat hypothalamus reveals a mixture of vasopressin (VP)- and oxytocin (OT)-containing neurons in the supraoptic (NSO), the paraventricular (NPV) and in five accessory nuclei (NAC). We describe the lateral hypothalamic nucleus (NLH), a new accessory nucleus, lying at the junction of the internal capsule and pallidum, and possibly involved in drinking behavior. Previously characterized incompletely in mammals, the four other accessory nuclei consist of the circularis (NC), anterior fornical (NAF), posterior fornical (NPF) and retrochiasmatic (NRC). The two peptidergic cell types, VP and OT, are equally mixed in the NPV and the NAC, but in the NSO VP neurons predominate. The perikarya of these VP and OT neurons do not show distinct morphological differences at the level of light microscopy. The organization of magnocellular neuroscretory neurons in the cat hypothalamus closely resembles that described in other mammals with the exception of the unique presence of the lateral hypothalamic accessory nucleus.