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We have isolated more than 12,000 clones containing microsatellite sequences, mainly consisting of (CA)n dinucleotide repeats, using genomic DNA from the BN strain of laboratory rat. Data trimming yielded 9636 non-redundant microsatellite sequences, and we designed oligonucleotide primer pairs to amplify 8189 of these. PCR amplification of genomic DNA from five different rat strains yielded clean amplification products for 7040 of these simple-sequence-length-polymorphism (SSLP) markers; 3019 markers had been mapped previously by radiation hybrid (RH) mapping methods (Nat Genet 22, 27-36, 1998). Here we report the characterization of these newly developed microsatellite markers as well as the release of previously unpublished microsatellite marker information. In addition, we have constructed a genome-wide linkage map of 515 markers, 204 of which are derived from our new collection, by genotyping 48 F2 progeny of (OLETFxBN)F2 crosses. This map spans 1830.9 cM, with an average spacing of 3.56 cM. Together with our ongoing project of preparing a whole-genome radiation hybrid map for the rat, this dense linkage map should provide a valuable resource for genetic studies in this model species.

A whole-genome radiation hybrid (RH) panel was used to construct a high-resolution map of the rat genome based on microsatellite and gene markers. These include 3,019 new microsatellite markers described here for the first time and 1,714 microsatellite markers with known genetic locations, allowing comparison and integration of maps from different sources. A robust RH framework map containing 1,030 positions ordered with odds of at least 1,000:1 has been defined as a tool for mapping these markers, and for future RH mapping in the rat. More than 500 genes which have been mapped in mouse and/or human were localized with respect to the rat RH framework, allowing the construction of detailed rat-mouse and rat-human comparative maps and illustrating the power of the RH approach for comparative mapping.

We have developed an eXtremely-low-current Low Energy Electron Diffraction (XLEED) apparatus equipped with a micro-channel plate and a position-sensitive detector which reduces electron beam damage and charge-up effects and makes it possible to study the structure of physisorbed films. This XLEED system is combined with the ellipsometer system which monitors the thickness of a physisorbed film. We observed Xe overlayer on Ag (111) and grahpite (0001) surfaces. We found that a thick Xe films on Ag (111) showed a single crystal structure which keeps relative orientation to the substrate.

The association between human papillomavirus (HPV) and anogenital tumors, especially cervical cancer, is well documented. However, it remains unclear whether there is also a correlation between HPV infection and human breast cancer.We used PCR and Southern blot hybridization to analyze HPV-related DNA specimens from 32 cases of invasive ductal carcinoma operated upon in the Shanghai region of China.DNA derived from HPV33 was detected in 14 cases (43.8%). No HPV16 or HPV18 DNA was detected in any of the cases in this study. This is the first report demonstrating a correlation between HPV33 infection and breast cancer.Our results suggest that HPV33 infection may be involved in the pathogenesis of breast cancer in Chinese.

To identify genetic determinants relevant to non-insulin-dependent diabetes mellitus (NIDDM), we performed a genome-wide analysis for quantitative trait loci (QTLs) using 359 backcross progeny of the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. The OLETF strain is a well-studied animal model of obese NIDDM, with features of hyperinsulinemia, hyperglycemia, insulin resistance, and abundant abdominal fat. Our extensive genomic scanning with 218 markers revealed nine significant QTLs, including a strong determinant of obesity on chromosome 1 (Dmo1: LOD = 13.99, for body weight). Two highly significant QTLs for glucose homeostasis were found, one on chromosome 1 (Dmo4 LOD = 7.16, for postprandial glucose level) and the other on chromosome X (Dmo11/Odb1: LOD = 7.81, for postprandial glucose level). These data are comparable to results of our previous studies of the OLETF rat.

The intravenous injection of isoprenaline (10 nmole/kg) into conscious beagle dogs caused significant increases in the blood level of lactate, glucose, FFA, insulin and cyclic AMP. These metabolic alterations induced by isoprenaline were blocked completely by pretreatment of the dog with propranolol (1 mg/kg). Butoxamine (10 mg/kg) antagonized isoprenaline-induced increases in glucose, lactate and insulin, but not the increases in FFA. Practolol (10 mg/kg) diminished the increase in blood FFA very strongly. Salbutamol, which is known to be an agonist of the β2-subtype in its bronchomotor and cardiovascular actions, produced marked increases in the blood concentrations of lactate, glucose and insulin but were without effect on the FFA level. Thus metabolic responses of conscious beagle dogs to β-adreboceptor agonists appeared to depend differentially on two types of β-adrenoceptors: β1-adrenoceptors are largely involved in lipolysis while β2-adrenoceptors are involved in the regulation of blood glucose metabolism and insulin secretion. A new β-adrenoceptor agonist, 5-(1-hydroxy-2-isopropylaminobutyl)-8-hydroxycarbostyril hydrochloride hemihydrate (Procaterol), was classified as a β2- agonist, because it markedly increased plasma concentrations of glucose, lactate and insulin but increased the plasma level of FFA to a lesser degree. The order of potency of β2-agonists was procaterol salbutamol trimetoquinol. Metabolic responses of beagle dogs would be useful for appreciating the selectivity and potency of β-adrenoceptor agonists and antagonists.

dl-(1245/36)-2,3,4,5,6-Pentachlorocyclohexanecarbonitrile was synthesized from (1234/ 56)-1,4,5,6-tetrachloro-2,3-epoxycyclohexane (α-BTC cis-epoxide). dl-(1245/36)-2,3,4,5,6-Pentachloro-1-methylcyclohexane was synthesized from the nitrile via dl-(1245/36)-2,3,4,5,6-pentachlorocyclohexylmethanol, the structure of which was confirmed by PMR spectroscopy using spin decoupling techniques and the shift reagent, Eu(DPM)3. This series of compounds was shown to have the same configuration as γ-BHC. The conformational equilibrium of these compounds is discussed. dl-(1245/36)-2,3,5,6-Tetrachloro-1,4-dimethyl-cyclohexane was synthesized by a stepwise route involving a Diels-Alder reaction of trans,trans-hexadiene-2,4 with maleic anhydride.

Intraperitoneal injection of epinephrine caused a slight but significant increase in cyclic AMP in the liver and skeletal muscle in 5–10 min. Likewise, there was a significant increase in cyclic AMP in the muscle and adipose tissue 5 min after the injection of isoproterenol. However, no change was detected in the cardiac muscle. Pretreatment of rats with theophylline was so effective in enhancing responses of tissue cyclic AMP as to make it possible to detect a 2- to 3-fold increase of cyclic AMP even in the heart. The maximal increases in tissue cyclic AMP induced by 500 μg/kg of isoproterenol or epinephrine were blocked by carteolol, a new beta-adrenergic blocking agent, at doses of 10–100 μg/kg, regardless of whether or not the rats had been treated with theophylline. In contrast, neither the increase of liver cyclic AMP by glucagon nor the increase of adrenal cyclic AMP by adrenocorticotropic hormone (ACTH) was affected by this agent. Blood cyclic AMP rose sharply after isoproterenol, the maximal response attaining 20- to 30-fold of the preinjection level. Based on this tremendous increase of blood cyclic AMP, the dose of isoproterenol and carteolol required for the half-saturation of the beta-adrenergic receptor was calculated as 20–30 and 0.5 μg/kg of body wt respectively. These values are in the same order as the respective values obtained from the response of carbohydrate and lipid metabolites in blood.

Lindane analogs, in which one or two chlorine atoms are replaced by various substituents, exhibit convulsive and lethal effects on Periplaneta americana (L.). Some analogs are as active as lindane. These effects are well related to the neuroexcitatory action which produces after-discharges in the central nervous system. Carbamate insecticides have potent convulsive and lethal effects on P. americana , which are also related to after-discharges produced in nerve cords. Convulsion caused by lindane analogs and carbamates is solely attributable to their neuroexcitatory effects on the nervous system, in spite of the difference in their ultimate modes of action.

The neuroexciting activity of DDT and its analogs to produce repetitive responses on the nerve cord of Periplaneta americana was determined using the extracellular electrode method. The convulsive activity on P. americana and the insecticidal effect on Callosobruchus chinensis were also examined. It was found that the convulsive and insecticidal activities increase almost proportionally with increase in the neuroexciting activity within a set of p,p′-substituted DDT analogs. The intimate connections among these biological effects suggest that symptoms such as convulsion and death caused by DDT analogs are closely related with their neuroexcitory effect and there is a common mode of action in spite of differences in insect species.

Increases in blood concentrations of glucose induced by epinephrine, of lactate induced by epinephrine and isoproterenol, and of glycerol and insulin induced by isoproterenol in rats showed graded responses dependent on the dose of the catecholamines and were blocked also progressively by increasing doses of 5-(3-tert-butylamino-2-hydroxy)propoxy-3,4-dihydrocarbostyril hydrochloride (carteolol), a new beta-adrenergic blocking agent. The ed 50 estimated for these metabolic parameters, other than blood insulin, was 100–200 μg/kg of body wt for epinephrine and 10–20 μg/kg for isoproterenol, while the “corrected id 50” for carteolol, reflecting the dissociation constant of the antagonist-receptor complex, was 1–3 μg/kg. It is concluded that the beta-adrenergic receptors of the same character concerning the affinity to agonists and antagonists mediate the increase of blood levels of these carbohydrate and lipid intermediary metabolites, and that the affinity of carteolol is one order higher than that of isoproterenol, which in turn is ten times higher than that of epinephrine. In contrast, much higher ed 50 for isoproterenol and “corrected id 50” for carteolol were obtained when hyperinsulinemia was used as a measure of beta action, suggesting that the beta-adrenergic receptor mediating pancreatic secretion of insulin is distinct in nature from the receptors involved in the control of carbohydrate and lipid metabolism. Comparison of the potency of carteolol with those of propranolol and pindolol showed that carteolol is the most potent beta-adrenergic blocking agent.

A novel microbial method for the production of 2',3'-dideoxynucleosides by transdideoxyribosylation has been developed. By screening microorganisms producing 2',3'-dideoxyadenosine (DDA) from 2',3'-dideoxyuridine (DDU) and adenine, Escherichia coli AJ 2595 was selected as the best producer. Optimal pH and temperature for the DDA-producing reaction were ca. 6.5 and 50 degrees C, respectively. Pi seemed to be an essential factor for the reaction, and its optimal concentration was ca. 25 mM. Moreover, polyethylene glycol had a notable effect on DDA production. Under the best conditions established, 52 mM DDA was obtained from 100 mM DDU and 100 mM adenine after 48 h of incubation from resting cells of E. coli AJ 2595. This strain could also produce 2',3'-dideoxynucleosides, such as 2',3'-dideoxyinosine (DDI), 2',3'-dideoxyguanosine, and 2',3'-dideoxythymidine, from DDU and the corresponding bases. In particular, this strain could produce DDI in high yield (ca. 32 mM from 100 mM DDU and 100 mM hypoxanthine) after 24 h of incubation. However, 2',3'-dideoxycytidine was not produced from DDU and cytosine by resting cells of E. coli AJ 2595.

The kinetics (absorption, distribution and excretion) of carteolol were investigated after oral and intravenous administration to man, rats, Beagle dogs and rabbits. The half-life of carteolol in plasma was 1.22 approximately 1.45 hr in rats, 1.73 approximately 2.08 hr in dogs and 1.42 approximately 1.43 hr in rabbits, and was independent of the route of administration. The absorption rate constants, obtained from log(C1-C) approximately time plot, after oral administration were 1.89 hr-1 in rats, 1.04 hr-1 in dogs and 1.54 hr-1 in rabbits. There were no differences between tablet and film coated tablet in the pharmacokinetic parameters of carteolol in man after oral 30 mg (tablet or film coated tablet) administration [half life (t1/2)=4.50 hr (tablet), 4.30 hr (film coated tablet), elimination rate constant (k2) equals 0.154 hr-1 (tablet), 0.161 hr-1 (film coated tablet)]. The elimination rate constant, obtained from Sigma-minus plot after 2, 5 and 10 mg oral administration, was 0.137 approximately 0.160 hr-1.

When anesthetized rats were exposed to microwave (power output 1.3 kw, frequency 2,450 MHz), the cyclic AMP phosphodiesterase activity showed a rapid decline in the skeletal muscle, heart, trachea and lung; no activity essentially could be detected after a 30 sec irradiation. Cyclic AMP levels in these tissues also decreased rapidly to constant values within 30 sec. Concentrations of cyclic AMP in the heart, skeletal muscle, trachea and lung measured by the tissue fixation with liquid nitrogen were approximately 3, 3, 4 and 4 times higher than those after microwave irradiation, respectively. The intravenous injection of procaterol (1 mu mol/kg), a beta 2-adrenoceptor agonist, caused a 6-fold increase in the trachea cyclic AMP level when measured after microwave fixation but only a 2-fold increase when measured after liquid nitrogen fixation. It is concluded that rapid tissue fixation by microwave irradiation may provide a useful means for obtaining reliable values of the tissue cyclic AMP content.

The behavior of the fatigue crack under the narrow band random stress intensity factor was studied experimentally. It was found that stress intensity factor governs the fatigue crack growth rate under random load process as well as under deterministic load sequences, and the crack growth rate in the short range showed noticeable fluctuation while that in the long range was almost constant implying that Miner's rule could be applied for the crack growth provided that the constants were determined from random fatigue test.A small digital system with a micro-CPU and the associated software developed for this study was found suitable for random fatigue tests.