Routine measurement of urinary total estrogens of the female Japanese monkey as an index for estimating the time of ovulation

The fluorometry of urinary total estrogens ofBrown et al. (1968) has been modified and successfully applied to the routine measurement of urinary estrogens in Japanese monkeys. Serial analysis during the menstrual cycle of the Japanese monkey has shown typical changes in urinary total estrogens with a distinct midcycle peak which preceded the day of ovulation by 0–2 days. The technique is valuable in an accurate estimation of the time of ovulation for successful programmed breeding of the Japanese monkey.     

Resistance to Active Oxygen Toxicity of Transgenic Nicotiana tabacum that Expresses the Gene for Glutathione Reductase from Escherichia coli

A chimeric gene consisting of a gene from Escherichia coli thatencodes glutathione reductase (GR), the 35S promoter of cauliflowermosaic virus and the terminator sequences of the gene for nopalinesynthase, was introduced into tobacco (Nicotiana tabacum SRI)cells via a Ti plasmid vector. Expression of the bacterial genein transformed plants and their descendants was confirmed byimmunochemical analysis. GR activity in leaf extracts variedamong transgenic plants, ranging from about 1.0 to 3.5 timesthe control level. These transgenic plants exhibited lower susceptibilityto paraquat than control plants in terms of the extent of visiblefoliar damage, a result that suggests that GR may play an importantrole in the detoxification of active oxygen in the cytoplasmicmatrix of plant cells. However, the transgenic plants were nomore resistant to ozone than were the controls, both in termsof the extent of visible foliar damage and with respect to photosyntheticactivity. (Received January 28, 1991; Accepted May 9, 1991)     

New Indices for Predicting Glycaemic Variability

Blood glucose variability is known to be associated with increased risk of long-term complications. Reliable indices for predicting hyperglycaemic and hypoglycaemic fluctuations are therefore needed. Glycaemic standard deviation (SD) obtained by continuous glucose monitoring correlates closely with nine previously described glycaemic variability formulas. Here, new indices predictive of glycaemic variability were developed, which can be calculated from laboratory measures based on a single blood draw. The indices included the glycated albumin (GA) to HbA1c ratio (GA/A1c ratio) and the fasting C-peptide immunoreactivity (FCPR) to fasting plasma glucose (FPG) ratio (FCPR index). Predictive values of these indices were assessed in 100 adults with diabetes. GA/A1c ratio and FCPR index showed close associations with glycaemic SD in addition to the nine existing glucose variability formulas. Subjects with a GA/A1c ratio ≥2.8 and FCPR index <3.0 showed the greatest SD and longest durations of hypoglycaemia, while those with a GA/A1c ratio <2.8 and FCPR index ≥3.0 had smaller SDs and little sign of hypoglycaemia. In adults with diabetes, a high GA/A1c ratio and low FCPR index value reflect higher glycaemic excursions, irrespective of diabetes type. Simultaneous measurements of GA, HbA1c, FPG and FCPR may help to identify a group of patients who warrant closer monitoring in relation to glycaemic variability and hypoglycaemia.     

Thermal Characteristics of C4 Photosynthetic Enzymes from Leaves of Three Sugarcane Species Differing in Cold Sensitivity

Phosphoenolpyruvate carboxylase, NADP-malate dehydrogenase andNADP-malic enzyme in desalted extracts from the leaves of threesugarcane species differing in cold sensitivity were relativelystable at cold temperatures, and their Arrhenius plots appearedas straight lines. Pyruvate,P_i dikinase (PPDK) from the threespecies was cold-inactivated, and its Arrhenius plots exhibiteda clear break-point around 10.6°C. Analysis of cold labilityof PPDK using deuterium oxide and Triton X-100 showed that theinteractions between the subunits possibly involve hydro-phobicbonds which would lead to cold lability. There were no apparentdifferences among the three sugarcane species in the thermalproperties of the four C₄ photosynthetic enzymes. The resultssuggest that the differences in cold sensitivity of sugarcanephotosynthesis may not relate to the thermal properties of C₄photosynthetic enzymes per se. ¹ Present address: Department of Biochemistry, University ofNebraska, Lincoln, NE 68588-0664, U.S.A.     

Effect of Trypsin Treatment on the ATPase Activity of Myofibrils from the Stored Rabbit Muscle

The extent of activation of myofibrillar ATPase activity by trypsin treatment has been measured.

When myofibril (5 mg/ml) was treated with a low concentration of trypsin (2.5 μg/ml), the Mg-modified ATPase activity of myofibrils at a low ionic strength increased appreciably, while the EDTA-enhanced ATPase activity of myofibrils at a high ionic strength did not change with the progress of trypsin digestion.

The dependence of myofibrillar ATPase activity on KCl concentration also became greater with the progress of trypsin digestion.

Trypsin treatment caused 5-fold increase in the Mg-modified ATPase activity of 0-myofibril, when treated with trypsin in a ratio of 1 to 2000 myofibril for 80 min. Under the same condition, the ATPase activity of 1-myofibril increased by about 150%, whereas that of 8-myofibril increased by approximately 50%.

When myofibrils were treated with trypsin in a ratio of 1 to 200 myofibril, the Mg-ATPase activity of 8-myofibril decreased earlier than that of 1-myofibril did by about 20 min.

Experimental results obtained in this study were enough to confirm that the myofibrils from the aged muscle are more susceptible to tryptic action.

An assumption was made that the structural alteration of myofibrils during aging might be attributed to the change in thin filament of myofibrils, including Z-lines, which are mainly due to the change in the native tropomyosin of thin filaments.     

Urinary estrogens,progesterone, and LH changes during normal menstrual cycles of a captive female pileated gibbon (Hylobates pileatus)

Urinary steroid hormones and luteinizing hormone (LH) were monitored in a female pileated gibbon. The LH concentration almost peaked the day after estrogens peaks. The progesterone increased sharply after the LH peaks. Our results revealed for the first time the relationship between daily changes in urinary hormones throughout normal menstrual cycles in pileated gibbon.     

Differential expression of two BMP antagonists, gremlin and Follistatin, during development of the chick feather bud

Expression of four BMP antagonist genes, noggin, chordin, gremlin and Follistatin, was examined during chick feather development. Although expression of noggin and chordin was not detected, gremlin and Follistatin were expressed differentially in feather buds. The differential expression patterns of gremlin and Follistatin change dynamically from the nascent inter-feather bud region to the posterior domain of the feather bud.     

Synthesis and hybridization of 2′-O-methyl-RNAs incorporating 2′-O-carbamoyluridine and unique participation of the carbamoyl group in U–G base pair

2′-O-Carbamoyluridine (U_cm) was synthesized and incorporated into DNAs and 2′-O-Me-RNAs. The oligonucleotides incorporating U_cm formed less stable duplexes with their complementary and U_cm–U, U_cm–C single-base mismatched DNAs and RNAs in comparison with those without the carbamoyl group. On the contrary, the T_m analyses revealed that the duplexes with a mismatched U_cm–G base pair showed almost the same thermostability as the corresponding unmodified duplexes. Molecular dynamics (MD) simulations of the U_cm-modified 2′-O-Me-RNA/RNA duplexes with U_cm–G mismatched base pair suggested that the carbamoyl group could participate in the U_cm–G base pair by an additional intermolecular hydrogen bond between the carbamoyl oxygen and the H2 of the guanine base.