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T Jia

Publications and source records attributed to T Jia.

16 recordsLinked to original sources
PubMed2025

A genome-wide association study of methamphetamine use among people with HIV.

BACKGROUND: Amphetamine-like stimulants are the most used psychostimulants in the world; methamphetamine use is the most prevalent in people with HIV. Prolonged methamphetamine use can cause lasting damage to the heart, gut, and brain, as well as auditory hallucinations and paranoid thinking. However, relatively little is known about methamphetamine use and its genetic contributors. METHODS: Using genetic information from the Centers for AIDS Research Network of Integrated Clinical Systems (CNICS) cohort, we conducted a multi-ancestry genome-wide association study (GWAS) of methamphetamine use among people with HIV (n&#x2009;=&#x2009;1,196 reported ever use, n&#x2009;=&#x2009;4,750 reported never use). RESULTS: No single nucleotide polymorphism was statistically associated with methamphetamine use at the genome-wide level (p&#x2009;<&#x2009;5 * 10-8) in our study. Further, we did not replicate previously suggested genetic variants from other studies (all p&#x2009;>&#x2009;0.05 in our analysis). DISCUSSION: Our study suggests that there is no single strong genetic contributor to lifetime use of methamphetamine in people with HIV enrolled in CNICS. Larger studies with more refined outcome assessment are warranted to further understand the contribution of genetics to methamphetamine use and use disorder. Investigation into social and environmental contributors to methamphetamine use are similarly necessary.

Humans↗
PubMed2001

Regulation by GDI of RhoA/Rho-kinase-induced Ca2+ sensitization of smooth muscle myosin II.

We characterized the role of guanine nucleotide dissociation inhibitor (GDI) in RhoA/Rho-kinase-mediated Ca2+ sensitization of smooth muscle. Endogenous contents (approximately 2-4 microM) of RhoA and RhoGDI were near stoichiometric, whereas a supraphysiological GDI concentration was required to relax Ca2+ sensitization of force by GTP and guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS). GDI also inhibited Ca2+ sensitization by GTP. G14V RhoA, by alpha-adrenergic and muscarinic agonists, and extracted RhoA from membranes. GTPgammaS translocated Rho-kinase to a Triton X-114-extractable membrane fraction. GTP. G14V RhoA complexed with GDI also induced Ca2+ sensitization, probably through in vivo dissociation of GTP. RhoA from the complex, because it was reversed by addition of excess GDI. GDI did not inhibit Ca2+ sensitization by phorbol ester. Constitutively active Cdc42 and Rac1 inhibited Ca2+ sensitization by GTP. G14V RhoA. We conclude that 1) the most likely in vivo function of GDI is to prevent perpetual "recycling" of GDP. RhoA to GTP. RhoA; 2) nucleotide exchange (GTP for GDP) on complexed GDP. RhoA/GDI can precede translocation of RhoA to the membrane; 3) activation of Rho-kinase exposes a hydrophobic domain; and 4) Cdc42 and Rac1 can inhibit Ca2+ sensitization by activated GTP. RhoA.

Amides↗
PubMed2000

[The effects of electric copper needle on venous thrombosis in the rat].

OBJECTIVE: In order to study the relation between the electric copper needle and venous thrombosis in the rat. METHODS: 90 rats were divided into two groups, each using either the superficial epigastric vein or the femoral vein for the experiment. The relations of voltage, current, electrifying time and venous thrombosis were studied and the histological changes were observed. RESULTS: 1. 1.4 V DC did not damage the vessel-nerve. 2. The current declined with time to 0.1 mA. 3. When the diameters of the copper needle and the vein were similar (P > 0.05), the thrombogenesis time was from 5.5 to 10.5 minutes. When the diameters of the copper needle and the vein were different (P < 0.05), the thrombogenesis time was from 7.5 to 17.5 minutes. CONCLUSIONS: For the electric copper needle to get ideal treatment, the best voltage is 4 V DC for 5.5 to 10.5 minutes or 7.5 to 17.5 minutes.

Animals↗
PubMed1999

Stimulation of breast cancer invasion and metastasis by synuclein gamma.

We recently identified and cloned novel breast cancer-specific gene BCSG1 by direct differential cDNA sequencing. BCSG1 has a great sequence homology with the Alzheimer's disease related neural protein synuclein (SNC); thus, it was also named SNC-gamma. Overexpression of SNC-gamma in breast cancer cells leads to a significant increase in motility and invasiveness in vitro and a profound augmentation of metastasis in vivo. Our data suggest that this member of the neural protein SNCs might have important functions outside the central nervous system and may play a role in breast cancer progression.

Animals↗
PubMed1999

Diphtheria toxin fused to granulocyte-macrophage colony-stimulating factor and Ara-C exert synergistic toxicity against human AML HL-60 cells.

Human granulocyte-macrophage colony-stimulating factor fused to truncated diphtheria toxin (DT388-GM-CSF) sensitized wild-type and Bcl2-overexpressing HL60 human leukemia cells to intoxication by Ara-C based on proliferation and clonogenic assays. The toxin/drug combination showed dramatic synergistic toxicity with combination indices of < 0.1. Synergy was not seen with two other protein synthesis inhibiting drugs--ricin and cycloheximide nor with GMCSF alone. No changes in Ara-C incorporation into cellular DNA or cell cycle occupancy were seen. As compared to exposure to DT388-GM-CSF or Ara-C alone, co-treatment produced significant increases in cytosolic accumulation of cytochrome c, a higher percentage of cells with loss of mitochondrial membrane potential and an increase in reactive oxygen species and morphologic changes of apoptosis, and a greater induction of poly(ADP-ribose) polymerase (PARP) and DNA fragmentation factor 45 (DFF45) cleavage activities of caspase 3. Co-treatment did not significantly alter Bcl2, Bcl-xL, Bax or Fas receptor (FasR), but modestly increased Fas ligand (FasL) protein. These finding suggest that co-treatment with DT388-GM-CSF may lead to a lowered apoptotic threshold and clonogenic survival of human AML blasts due to Ara-C. These observations also suggest that clinical trials of combination therapy may be warranted in patients with AML.

Acute Disease↗
PubMed1998

The effects of the Rho-kinase inhibitor Y-27632 on arachidonic acid-, GTPgammaS-, and phorbol ester-induced Ca2+-sensitization of smooth muscle.

The effects of the Rho-kinase inhibitor, Y-27632 [1] on Ca2+-sensitization of force induced by arachidonic acid (AA), phorbol 12,13-dibutyrate (PDBu), GTPgammaS, and by the stable thromboxane analog, 9,11-dideoxy-9alpha,11alpha-methanoepoxy-PGF2alpha (U-46619), were determined in alpha-toxin-permeabilized smooth muscles. Y-27632 relaxed (up to 99%) Ca2+-sensitization by GTPgammaS (10 microM) and U46619 (1 microM), but not by PDBu (20 microM), and reduced GTPgammaS-induced myosin light chain (MLC20) phosphorylation from 28% to 17% (P=0.002). GTPgammaS-induced force sensitization was inhibited by Y-27632 more potently when the inhibitor was added during the plateau of force than prior to stimulation. In alpha-toxin-permeabilized smooth muscle, Y-27632 inhibited AA (50 microM)-induced Ca2+-sensitization of force (by 66 +/- 1.3%) and reduced MLC20 phosphorylation. In contrast, Y-27632 did not relax force Ca2+-sensitized by AA in smooth muscle permeabilized with Triton X-100. We conclude that (i) AA induces Ca2+-sensitization through dual mechanisms, one mediated by Rho-kinase (or a related kinase), and (ii) Rho-kinase is not required for phorbol ester-induced Ca2+-sensitization.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1998

[Quality standards of processed nutmegs].

The quality standards of nutmeg and its processed products were studied in such aspects as volatile oil content, extract determination, moisture content, microscopic characteristics, thin-layer chromatography, and so on. This provided a basis for drawing up the quality standards.

Drugs, Chinese Herbal↗
PubMed1997

Identification of a breast cancer-specific gene, BCSG1, by direct differential cDNA sequencing.

A high-throughput direct-differential cDNA sequencing approach was employed to identify genes differentially expressed in normal breast as compared with breast cancer. Approximately 6000 expressed sequence tags (ESTs) from cDNA libraries of normal breast and breast carcinoma were selected randomly and subjected to EST-sequencing analysis. The relative expression levels of more than 2000 unique EST groups were quantitatively compared in normal versus cancerous breast. Of many putative differentially expressed genes, a breast cancer-specific gene, BCSGC1, which was expressed in high abundance in a breast cancer cDNA library but scarcely in a normal breast cDNA library, was identified as a putative breast cancer marker. In situ hybridization analysis demonstrated stage-specific BCSG1 expression as follows: BCSG1 was undetectable in normal or benign breast lesions, showed partial expression in ductal carcinoma in situ, but was expressed at an extremely high level in advanced infiltrating breast cancer. The predicted amino acid sequence of BCSG1 gene has a significant sequence homology to the non-amyloid beta protein fragment of the Alzheimer's disease amyloid protein. BCSG1 overexpression may indicate breast cancer malignant progression from benign breast or in situ carcinoma to the highly infiltrating carcinoma.

Amino Acid Sequence↗
PubMed1997

[Comparative study on nutmeg, mace and their processed products].

The contents of volatile oil, myristicin, safrol and methyleugenol, as well as the composition and content of fatty oil in nutmeg, mace and their processed products were comparatively studied. The composition of volatile oil and the detection of trimyristin were compared by TLC. A scientific basis for the development and application of mace has thus been provided.

Allylbenzene Derivatives↗
PubMed1996

[Comparative research on the constituents of the volatile oil in the rhizome of Cibotium barometz (L.) J. Sm. and its processed products].

Volatile oil was extracted from the rhizome of Cibotium barometz for the first time. Its content was determined to be 83.3 micrograms/g, decreasing significantly after the drug was processed. Twelve constituents from the volatile oil were identified by method of GC-MS. The main constituents were organic acids. The contents of palmitic acid and linoleic acid were the highest. After Cibotium barometz was processed, some constituents were found decreasing and some increasing.

Drugs, Chinese Herbal↗
PubMed1992

[Relationship among hyperglycemia growth hormone (CSF) and insulin in serum of cerebral hemorrhage].

40 patients of stroke were studied. The results showed that in Cerebral hemorrhage the correlation between ascending Growth hormone (GH) of CSF and insulin of serum was negative, but the positive correlation between ascending GH (CSF) and hyperglycemia. In patients of cerebral thrombosis the results of values above were no correlation. The pathological significance in such cases was discussed.

Aged↗
PubMed1991

[Determination of myristicin and safrol in the volatile oil of semen Myristicae and its processed products by TLC-scanning].

This paper reports the determination of myristicin and safrol in the volatile oil of Semen Myristicae and its processed products by TLC-Scanning. The results showed that in the processed products myristicin decreased markedly and safrol decreased slightly. The quantity of myristicin roasted with paste less than with wheat bran less than with talcum powder less than the unprocessed one. The toxicity of Semen Myristicae is related to the quantities of myristicin.

Allylbenzene Derivatives↗