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J Yao

Publications and source records attributed to J Yao.

299 records · Page 17Linked to original sources
PubMedDate not supplied

Mitogenic effect of neuropeptide Y in rat vascular smooth muscle cells.

Neuropeptide Y (NPY) is a vasoconstrictor released with norepinephrine from perivascular sympathetic nerves. Since sympathetic nerves appear to play a role in vascular smooth muscle cell (SMC) hypertrophy, we studied the effects of NPY on proliferation of cultured rat aorta- and vena cava-derived SMC. Both cell types displayed high-affinity NPY binding sites with displacement characteristics of [Pro34]NPY > NPY(13-36) > NPY(18-36) in aorta and [Pro34]NPY = NPY(13-36) = NPY(18-36) in the vena cava. Incubation with NPY (50-1000 nM) for 48 h increased by up to twofold cell number and [3H]-thymidine incorporation in both cell types (aortic more sensitive to NPY than venous). Following incubation with NPY, the disappearance of NPY immunoreactivity (-IR) from media was markedly delayed in the presence of SMC, and cell content of NPY-IR increased in a dose-dependent manner, indicating that SMC either diminish degradation of the peptide (possibly by internalization) or secrete endogenous NPY (or both). Structure-activity relationship studies with NPY(18-36) indicated involvement of Y1 receptors in mitogenesis. Thus, NPY has a mitogenic effect (probably mediated by Y1 receptors) and, therefore, may be a sympathetic trophic factor involved in vascular hypertrophy.

Animals↗
PubMedDate not supplied

Neuropeptide Y-like immunoreactivity in schizophrenia. Relationships with clinical measures.

Neuropeptide Y-like immunoreactivity (NPY-li) was measured in CSF of 35 drug-free chronic schizophrenic patients. Compared to a group of drug-free controls, CSF NPY-li was significantly higher in these patients. CSF NPY-li decreased with age and longer duration of illness. Measures of structural brain abnormalities on CT scans were significantly associated with lower CSF NPY-li. Relationships between NPY-li and schizophrenic behavior, i.e. positive symptoms, were observed only in the clinically stable (nonrelapsed) drug-free patients. In 31 of the patients CSF was obtained before and after withdrawal from haloperidol maintenance treatment. This withdrawal from haloperidol treatment was associated with a significant increase in CSF NPY-li. There was no significant difference in CSF NPY-li between patients who did and those who did not relapse within 6 weeks following haloperidol withdrawal. The present findings suggest a relationship of CSF NPY-li with various aspects of schizophrenia.

Adult↗
PubMedDate not supplied

SIRS-SS: a system for simulating IR/Raman spectra. 1. Substructure/subspectrum correlation.

An IR/RAMAN spectra simulation system is reported. The development of this software was based on the substructure/subspectrum relationships established for four different structural classes: small molecules, special fragments, atom-centered FRELs, and bond-centered FRELs (FREL: Fragment centered on an Environment which is Limited). Four corresponding knowledge-bases (now, at a pilot stage) are constructed from usual correlation charts or data analyses of large populations of compounds using data mining techniques.

Journal Article↗
PubMedDate not supplied

A genetic marker in the growth hormone receptor gene associated with body weight in chickens.

A genomic clone spanning 16 kb of the GH receptor gene was mapped and used as a probe for identifying restriction fragment length polymorphisms (RFLPs) in chickens. Several strains of meat-type and egg laying chickens were found to segregate for an HindIII RFLP located in the intron preceding exon 4. The polymorphic HindIII site overlapped with a poly(A) signal. Association of the HindIII RFLP with traits was analyzed in a random-bred White Leghorn strain in three generations using either selective or random genotyping. Both methods revealed significant association of the HindIII+ allele (presence of the poly(A) signal) with an increased juvenile body weight (130 days of age). In two meat-type strains divergently selected for size of the abdominal fat pad, the HindIII+ allele was coselected with leanness. The results indicate the presence of a genetic variant of the GH receptor gene which affects growth and abdominal fat deposition and which is relatively frequent in egg laying as well as in meat-type chickens.

Animals↗
PubMedDate not supplied

Markers within the regulatory region of the growth hormone receptor gene and their association with milk-related traits in Holsteins.

We studied sequence variations in the regulatory region of the bovine growth hormone receptor gene. A polymerase chain reaction (PCR)-based method for detecting AluI, AccI, and StuI restriction fragment length polymorphisms (RFLPs) in the 5' flanking region of the bovine growth hormone receptor gene was developed and tested for association with milk-related traits in Holstein bulls. Allele frequencies of the polymorphisms in two groups of Holstein progeny-tested bulls born from 1950 to 1970 and in the 1980s, respectively, were estimated. The allele frequency of the AluI(-) allele was 0.63 and 0.42 in the bulls from 1950 to 1970 and in the 1980s, respectively. The frequency of the StuI(-) allele was 0.14 and 0.07 in the two respective bull groups. Allele frequency for AccI(-) allele was about 0.22 in both bull groups. The differences in allele frequencies for the AluI polymorphism in the two bull groups were significantly different (P < or = .005). The AluI(+/+) bulls had a higher estimated breeding value (EBV) for fat (P < or = .016) than AluI(-/-) bulls. The average effect of allele substitution for the AluI polymorphism was +/- 8 for fat EBV. The AluI polymorphism could be further evaluated for use in marker-assisted selection in dairy cattle.

Alleles↗
PubMedDate not supplied

Trait association of a genetic marker near the IGF-I gene in egg-laying chickens.

The insulin-like growth factor I (IGF-I) gene was screened for genetic variants associated with trait means and trait correlations. Analysis of an unselected randomly mated White Leghorn population revealed a PstI restriction fragment length polymorphism (RFLP) in the 5' region of the gene which segregated at a frequency of 0.83 for the PstI(+) allele (presence of a PstI restriction site). A comparison of the three genotypic classes revealed that the PstI(-/-) genotype was associated with a significantly lower egg weight measured in three different time periods, while the PstI(+/-) genotype was significantly associated with a higher eggshell weight estimated from the egg weight and egg specific gravity. For eggshell weight, the effect was age dependent and significant only for the last two periods of egg laying. No genotype associations were found for body weight, feed consumption, and egg laying rates. Significant dominance effects of the IGF-I genotype were observed for two of the egg weight measurements and three of the eggshell weight estimates. Partial correlation analyses in the two most frequent genotypic classes, PstI(+/+) and PstI(+/-), revealed the presence of a regulatory loop between feed consumption, body weight, egg weight, and the rate of egg laying. Several aspects of this regulatory loop were different between the two genotypic classes. In particular, for the PstI(+/+) genotype, feed consumption was positively associated with egg weight, while there was no significant association for the PstI(+/-) genotype. Further, the degree of association of body weight with egg weight decreased with age in the genotypic class PstI(+/-), while it was constant for the PstI(+/+) genotype. The results indicated that the marker in the IGF-I gene was not only associated with changes in some trait means, but also with changes in the stability of the coordination between feed intake, body weight, and egg production traits.

Animals↗
PubMedDate not supplied

Tomography in a juvenile Tillaux fracture.

Juvenile Tillaux fractures are Salter-Harris Type III physeal fractures involving the lateral weight-bearing surface of the distal tibia. A recent case demonstrates the usefulness of tomography as an adjunct to routine radiographs as a more accurate means of diagnosing the amount and direction of fracture displacement, a critical factor when treatment decisions are made.

Adolescent↗
PubMedDate not supplied

Studies on the growth metabolism of Bacillus thuringiensis and its vegetative insecticidal protein engineered strains by microcalorimetry.

The metabolic power-times curves of Bacillus thuringiensis and its vegetative insecticidal protein engineered strains were determined at 30 degrees C by using a thermal activity monitor air Isothermal Microcalorimeter, ampoule method. From the power-times curves, the maximum power (Pmax) in the log phase, the growth rate constant (k), the generation times (tG), the time of the maximum power (tmax), the heat effects (Qlog) for log phase, and the total heat effect in 45 h (Qtotal) of B. thuringiensis strains can be obtained. The results indicate that their power-times curves are different. The relationship between their metabolic power-times curves and character of bacteria metabolism, and thermokinetics and gene expression were analyzed and discussed. The character of the bacteria power-times curves reflected the physiologic character of gene expression. The microcalorimetric method proved to be a reliable and sensitive tool for the assessment of the growth metabolism, the heat output in bacteria and its engineered strains. The determination of the thermokinetic character is beneficial to the control of fermentation.

Animals↗