The influence of oxygen on the survival and yield of DNA double-strand breaks in irradiated yeast cells.

Survival and induction of DNA double-strand breaks were studied in cells of Saccharomyces cerevisiae irradiated under oxic or anoxic conditions with 30 MeV electrons. A linear relationship between DNA double-strand breakage and dose was found in both cases. The o.e.r.-value for colony forming ability was found to be 1.9 +/- 0.2, whereas the o.e.r.-value for DNA double-strand breakage was 3.0 +/- 0.1. These results are not inconsistent with the idea that DNA double-strand breaks are involved in killing of yeast cells. The frequency of induction of DNA double-strand breaks was found to be 0.74 x 10(-11) double-strand breaks per g/mol per Gy when cells were irradiated under oxygen and 0.24 x 10(-11) double-strand breaks per g/mol per Gy under nitrogen.     

A requirement for cytoplasmic protein synthesis during chloroplast senescence in the aquatic plant Anacharis canadensis

Cycloheximide (CHI) at 1 µg/liter delayed the loss ofchlorophyll from detached Anacharis canadensis leaflets senescingin the dark. Chloramphenicol (CAP) and streptomycin (SM) slightlyaccelerated the loss. CHI was effective even during the laterstages of senescence in preventing further loss of chlorophyll.Senescence proceeded normally upon return of the leaflets intowater. The need for cytoplasmic protein synthesis during chloroplastsenescence and the types of proteins involved are discussed. (Received March 26, 1976; )     

Regression of Fibrosis and Reversal of Cirrhosis in Rats by Galectin Inhibitors in Thioacetamide-Induced Liver Disease

Galectin-3 protein is critical to the development of liver fibrosis because galectin-3 null mice have attenuated fibrosis after liver injury. Therefore, we examined the ability of novel complex carbohydrate galectin inhibitors to treat toxin-induced fibrosis and cirrhosis. Fibrosis was induced in rats by intraperitoneal injections with thioacetamide (TAA) and groups were treated with vehicle, GR-MD-02 (galactoarabino-rhamnogalaturonan) or GM-CT-01 (galactomannan). In initial experiments, 4 weeks of treatment with GR-MD-02 following completion of 8 weeks of TAA significantly reduced collagen content by almost 50% based on Sirius red staining. Rats were then exposed to more intense and longer TAA treatment, which included either GR-MD-02 or GM-CT-01 during weeks 8 through 11. TAA rats treated with vehicle developed extensive fibrosis and pathological stage 6 Ishak fibrosis, or cirrhosis. Treatment with either GR-MD-02 (90 mg/kg ip) or GM-CT-01 (180 mg/kg ip) given once weekly during weeks 8–11 led to marked reduction in fibrosis with reduction in portal and septal galectin-3 positive macrophages and reduction in portal pressure. Vehicle-treated animals had cirrhosis whereas in the treated animals the fibrosis stage was significantly reduced, with evidence of resolved or resolving cirrhosis and reduced portal inflammation and ballooning. In this model of toxin-induced liver fibrosis, treatment with two galectin protein inhibitors with different chemical compositions significantly reduced fibrosis, reversed cirrhosis, reduced galectin-3 expressing portal and septal macrophages, and reduced portal pressure. These findings suggest a potential role of these drugs in human liver fibrosis and cirrhosis.     

1H, 13C, and 15N backbone resonance assignments of the L124D mutant of StAR-related lipid transfer domain protein 4 (StARD4)

Protein-mediated cholesterol trafficking is central to maintaining cholesterol homeostasis in cells. START (Steroidogenic acute regulatory protein-related lipid transfer) domains constitute a sterol and lipid binding motif and the START domain protein StARD4 typifies a small family of mammalian sterol transport proteins. StARD4 consists of a single START domain and has been reported to act as a general cholesterol transporter in cells. However, the structural basis of cholesterol uptake and transport is not well understood and no cholesterol-bound START domain structures have been reported. We have undertaken the study of cholesterol binding and transport by StARD4 using solution state NMR spectroscopy. To this end, we report nearly complete ¹H, ¹⁵N, and ¹³C backbone resonance assignments of an inactive but well behaved mutant (L124D) of StARD4.     

The Evolution of Fruit Tree Productivity: A Review

The Evolution of Fruit Tree Productivity: A Review. Domestication of fruit trees has received far less attention than that of annual crop plants. In particular, very little is known about the evolution of fruit tree productivity. In the wild, most tree species reach reproductive maturity after a long period of juvenility and even then, sexual reproduction appears sporadically, often in a mode of masting. Environmental constraints limit trees’ reproductive activity in their natural, wild habitats, resulting in poor, irregular productivity. Early fructification and regular, high rates of productivity have been selected by people, unconsciously and consciously. The reviewed evidence indicates an evolutionary continuum of productivity patterns among trees of wild habitats, intermediary domesticates, and the most advanced domesticates. Alternate bearing appears to represent an intermediate step in the fruit tree evolutionary pathway. The existence of a molecular, genetic mechanism that controls trees’ sexual reproduction and fruiting pattern is suggested.     

Optimal trait scoring for age estimation

What are the effects that genetics has had on Anthropological research and how can we think anthropologically about Genetics? Just as genetic data have encouraged new hypotheses about human phenotypic variation, evolutionary history, population interaction, and environmental effects, so too has Anthropology offered to genetic studies a new interpretive locus in its history and perspective. This introduction examines how the fields of Anthropology and Genetics have arrived at a crucial moment at which their interaction requires careful examination and critical reflection. The papers discussed here exemplify how we may engage in such a trans-disciplinary conversation. They speak to the future of thoughtful interaction between genetic and anthropological literature and seek a new integration that embodies the holism of the human biological sciences.     

External micromorphology of the frons plate and its adjacent areas in workers of the oriental hornet

The micromorphology of the frons and the adjacent regions in young workers (1–24 hr of age) of the Oriental hornet Vespa orientalis and some adult worker hornets is described. The young workers still lack globular secretions at the bases of the setae. Such secretions do occur at the bases of the setae in the adult workers and are composed mainly of the elements Si, Al, S, Mg, Ca, Cl, and Fe. Contiguous with each of the ocelli is a gland that also secretes minerals. Young workers usually have a relatively large concentration of Ca in the glands behind the paired ocelli. The gland associated with the median anterior ocellus opens by an elongated sutura coronalis in the frons and contains various elements, predominantly Si, but also Ca. The setae (hairs) on the frons are arranged in concentric circles around each of the ocelli; they are long in the upper part of the frons but shorten gradually toward the tip of the frons. The tip lacks hair, but the cuticle bears elevated scales that project as cuticular protuberences. It appears that the ocelli and their associated glands, and the entire frons plate with its hairs and glands at the bases of the hairs in this region, comprise an equilibrium “organ” that senses changes in gravity. © 1992 Wiley-Liss, Inc.     

Twice daily versus four times daily insulin dose regimens for diabetes in pregnancy: randomised controlled trial

ObjectiveTo compare perinatal outcome and glycaemic control in two groups of pregnant diabetic patients receiving two insulin regimens.DesignRandomised controlled open label study.SettingUniversity affiliated hospital, Israel.Participants138 patients with gestational diabetes mellitus and 58 patients with pregestational diabetes mellitus received insulin four times daily, and 136 patients with gestational diabetes and 60 patients with pregestational diabetes received insulin twice daily.InterventionThree doses of regular insulin before meals and an intermediate insulin dose before bedtime (four times daily regimen), and a combination of regular and intermediate insulin in the morning and evening (twice daily regimen).ResultsMean daily insulin concentration before birth was higher in the women receiving insulin four times daily compared with twice daily: by 22 units (95% confidence interval 12 to 32) in patients with gestational diabetes and by 28 units (15 to 41) in patients with pregestational diabetes. Glycaemic control was better with the four times daily regimen than with the twice daily regimen: in patients with gestational diabetes mean blood glucose concentrations decreased by 0.19 mmol/l (0.13 to 0.25), HbA_1c by 0.3% (0.2% to 0.4%), and fructosamine by 41 μmol/l (37 to 45), and adequate glycaemic control (mean blood glucose concentration <5.8 mmol/l) was achieved in 17% (8% to 26%) more women; in patients with pregestational diabetes mean blood glucose concentration decreased by 0.44 mmol/l (0.28 to 0.60), HbA_1c by 0.5% (0.2% to 0.8%), and fructosamine by 51 μmol/l (45 to 57), and adequate glycaemic control was achieved in 31% (15% to 47%) more women. Maternal severe hypoglycaemic events, caesarean section, preterm birth, macrosomia, and low Apgar scores were similar in both dose groups. In women with gestational diabetes the four times daily regimen resulted in a lower rate of overall neonatal morbidity than the twice daily regimen (relative risk 0.59, 0.38 to 0.92), and the relative risk for hyperbilirubinaemia and hypoglycaemia was lower (0.51, 0.29 to 0.91 and 0.12, 0.02 to 0.97 respectively). The relative risk of hypoglycaemia in newborn infants to mothers with pregestational diabetes was 0.17 (0.04 to 0.74).ConclusionsGiving insulin four times rather than twice daily in pregnancy improved glycaemic control and perinatal outcome without further risking the mother.

Key messages

• Improving maternal glycaemic control during pregnancy is the key to better perinatal outcome
• In pregnant diabetic women insulin four times daily achieved better glycaemic control and lower rate of perinatal complications (hypoglycaemia, hyperbilirubinaemia) than insulin twice daily
• Better glycaemic control resulted from a larger total daily insulin dose
• The intensified regimen did not lead to higher rate of severe maternal hypoglycaemia