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C Jia

Publications and source records attributed to C Jia.

At least 19 recordsLinked to original sources
PubMed2001

A new approach to 4-alkylthio-1,3-dithiole-2-thione: an unusual reaction of a zinc complex of 1,3-dithole-2-thione-4,5-dithiolate.

[see reaction]. A new and facile approach to 4-alkylthio-1,3-dithiole-2-thione starting from easily accessible reactants was described. This approach was based on the unusual reaction of a zinc complex of 1,3-dithiole-2-thione-4,5-dithiolate with electrophilic reagents in the presence of 3-picolyl chloride hydrochloride/or 4-picolyl chloride hydrochloride/or pyridine hydrochloride.

Journal Article↗
PubMed2001

Risk factors for nodal recurrence after lymphadenectomy for melanoma.

BACKGROUND: The risk and outcome of regional failure after elective and therapeutic lymph node dissection (ELND/TLND) for microscopically and macroscopically involved lymph nodes without adjuvant radiotherapy were evaluated. METHODS: Retrospective melanoma database review of 338 patients (ELND 85, TLND 253) from 1970 to 1996 with pathologically involved lymph nodes. RESULTS: Regional recurrence occurred in 14% of patients treated with ELND (n = 12) and 28% of patients treated with TLND (n = 72; P = .009). Risk factors associated with nodal recurrence were advanced age, primary lesion in the head and neck region, depth of the primary lesion, number of involved lymph nodes, and extracapsular extension (ECE). For each nodal basin, the ELND group had a lower incidence of recurrence than the TLND group. The TLND group had larger lymph nodes, greater number of involved lymph nodes, and a higher incidence of ECE. The 10-year disease-specific survival was 51% vs. 30% for ELND and TLND, respectively (P = .0005). Nodal basin failure was predictive of distant metastasis, with 87% developing distant disease compared with 54% of patients without nodal recurrence (P < .0001). Of six patients who underwent a second dissection after isolated nodal recurrence, five patients have had a median disease-free interval of 79 months. CONCLUSIONS: After ELND or TLND, patients who have a large tumor burden (thick primary melanoma, multiply involved lymph nodes, ECE), advanced age, and a primary lesion located in the head and neck have a significantly increased likelihood of relapse and a decreased survival. Few patients present with an isolated nodal recurrence, but the majority can be salvaged by a second dissection.

Female↗
PubMed2001

Catalytic functionalization of arenes and alkanes via C-H bond activation.

Several novel synthetic reactions of arenes and alkanes discovered and investigated in our laboratory are summarized here. These include olefin arylation, hydroarylation of alkynes, hydroxylation of arenes, carboxylation of arenes and alkanes, and aminomethylation and acetoxylation of alkanes. Most of these reactions are catalyzed by highly electrophilic transition metal cationic species generated in situ in an acid medium, involving electrophilic metalation of C-H bonds of arenes and alkanes which lead to the formation of aryl-metal and alkyl-metal sigma-complexes.

Journal Article↗
PubMed2001

Chromosomal composition of micronuclei in mouse NIH 3T3 cells treated with acrylamide, extract of Tripterygium hypoglaucum (level) hutch, mitomycin C and colchicine, detected by multicolor FISH with centromeric and telomeric DNA probes.

The chromosomal composition of micronuclei (MN) induced by the model mutagens mitomycin (MMC) and colchicine (COL) as well as by acrylamide (AA) and the traditional Chinese medicine Tripterygium hypoglaucum (level) hutch (THH) in NIH 3T3 cells was analyzed by multicolor fluorescence in situ hybridization (FISH) using DNA probes for the centromere repeated minor satellite DNA and the telomeric hexamer repeat (TTAGGG). The majority of MN (78.6%) from treatment with MMC (0.1 microg/ml) did not show centromeric signals, reflecting the clastogenic action of MMC. Following treatment with COL (0.1 microg/ml), 74.5% of the MN showed centromeric signals and several telomeric signals, indicating that MN induced by this well-known aneugen were mainly composed of whole chromosomes. After treatment with AA (100, 200 and 400 microg/ml) both MN containing whole chromosomes and MN containing acentric fragments were found to increase in a dose-dependent manner, demonstrating that AA is not only a clastogen but also an aneugen. THH induced a high frequency of MN harboring whole chromosomes at all concentrations tested (5, 10 and 20 microl/ml) and produced a dose-dependent increase in fragment-containing MN, indicating that THH has both aneugenic and clastogenic potential.

3T3 Cells↗
PubMed2001

HUman MicroNucleus project: international database comparison for results with the cytokinesis-block micronucleus assay in human lymphocytes: I. Effect of laboratory protocol, scoring criteria, and host factors on the frequency of micronuclei.

Micronucleus (MN) expression in peripheral blood lymphocytes is well established as a standard method for monitoring chromosome damage in human populations. The first results of an analysis of pooled data from laboratories using the cytokinesis-block micronucleus (CBMN) assay and participating in the HUMN (HUman MicroNucleus project) international collaborative study are presented. The effects of laboratory protocol, scoring criteria, and host factors on baseline micronucleated binucleate cell (MNC) frequency are evaluated, and a reference range of "normal" values against which future studies may be compared is provided. Primary data from historical records were submitted by 25 laboratories distributed in 16 countries. This resulted in a database of nearly 7000 subjects. Potentially significant differences were present in the methods used by participating laboratories, such as in the type of culture medium, the concentration of cytochalasin-B, the percentage of fetal calf serum, and in the culture method. Differences in criteria for scoring micronuclei were also evident. The overall median MNC frequency in nonexposed (i.e., normal) subjects was 6.5 per thousand and the interquartile range was between 3 and 12 per thousand. An increase in MNC frequency with age was evident in all but two laboratories. The effect of gender, although not so evident in all databases, was also present, with females having a 19% higher level of MNC frequency (95% confidence interval: 14-24%). Statistical analyses were performed using random-effects models for correlated data. Our best model, which included exposure to genotoxic factors, host factors, methods, and scoring criteria, explained 75% of the total variance, with the largest contribution attributable to laboratory methods.

Adolescent↗
PubMed2001

[Percutaneous transluminal septal myocardial ablation in patients with hypertrophic obstructive cardiomyopathy: immediately and middle-term follow-up results].

OBJECTIVE: To evaluate the immediate and follow-up results of percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy (HOCM). METHODS: 15 patients with HOCM refractory to medication successfully underwent PTSMA under myocardial contrast echocardiography. RESULTS: The left ventricular outflow gradients (LVOTG) were reduced significantly (77.93 +/- 22.00) mm Hg to (14.8 +/- 15.0) mm Hg (P < 0.0001) immediately with a mean decrease of (5.75 +/- 2.87) mm Hg (P < 0.001) in left ventricular end diastolic pressure. The scores of SAM and mitral regurgition During a mean of 8.6 +/- 3.8(6-22) months follow-up, the patients heart function (NYHA) were greatly improved(3.4 +/- 0.5 vs 1.1 +/- 0.4, P < 0.001), and disappearance of angina pectoris, and exercise endurance improvement with steady hemodynamic improvement. CONCLUSION: PTSMA is effectively non-surgical treatment method for drug-refractory patients with HOCM.

Adolescent↗
PubMed2001

[Relations of electrolytes to the by-product CHCl3 produced in electrochemical disinfection].

OBJECTIVE: To investigate the relation of electrolytes(NaCl, Na2SO4) to the by-product CHCl3 produced in the electrochemical disinfection process. METHODS: Taking filtering water, we used the graphite and Ti (matrix)-Ti as electrodes, adjusted the current sample for analysis in different time, and determined the production of CHCl3 under different conditions. RESULTS: Na2SO4 had no effect on the production of CHCl3 in the electrolysis(P > 0.05). but NaCl had the effect and the higher the concentration of Cl- was, the more the production of CHCl3 increased. The production of CHCl3 increased with the length of electrolysis time, and it exceeded the national standard after 10 minutes' electrolysis using Ti (matrix)-Ti as electrodes. When graphite was used as electrodes, the production of CHCl3 was much less. CONCLUSION: Na2SO4 has no effect on the production of CHCl3. Our suggestion is that graphite should be used as the electrodes for electrochemical disinfection of drinking water.

Chloroform↗
PubMed2000

New method for preparation of coumarins and quinolinones via Pd-catalyzed intramolecular hydroarylation of C-C triple bonds.

A new and general method has been developed for preparation of coumarins and quinolinones by intramolecular hydroarylation of alkynes. Various aryl alkynoates and alkynanilides undergo fast intramolecular reaction at room temperature in the presence of a catalytic amount of Pd(OAc)(2) in a mixed solvent containing trifluoroacetic acid (TFA), affording coumarins and quinolinones in moderate to excellent yields with more than 1000 turnover numbers (TON) to Pd. The methodology proved to tolerate a number of functional groups such as Br and CHO. On the basis of isotope experiments, a possible mechanism involving ethynyl chelation-assisted electrophilic metalation of aromatic C-H bonds by in-situ generated cationic Pd(II) species has been discussed. Also the involvement of vinylcationic species has been suggested.

Catalysis↗
PubMed2000

Pd-catalyzed selective addition of heteroaromatic C-H bonds to C-C triple bonds under mild conditions.

Simple heteroarenes such as pyrroles and indoles undergo addition reactions to C-C triple bonds in the presence of a catalytic amount of Pd(OAc)(2) under very mild conditions, affording cis-heteroarylalkenes in most cases. The cleavage of aromatic C-H bonds is the possible rate-determining step in CH(2)Cl(2), and the addition of heteroaromatic C-H bonds to C-C triple bonds is in a trans-fashion.

Catalysis↗
PubMed2000

Efficient activation of aromatic C-H bonds for addition to C-C multiple bonds

Efficient electrophilic metalation of aromatic C-H bonds leading to new C-C bond formation through regio- and stereoselective addition to alkynes and alkenes has been realized by a catalytic amount (0.02 to 5 mole percent) of palladium(II) or platinum(II) compounds in a mixed solvent containing trifluoroacetic acid at room temperature. Various arenes undergo unexpected selective trans hydroarylation to terminal or internal C&cjs0812;C bonds inter- and intramolecularly with high efficiency (up to a turnover number of 4500 for palladium), especially for electron-rich arenes, giving thermodynamically unfavorable cis-alkenes, and the oxygen- and nitrogen-containing heterocycles. The simplicity, generality, and efficiency of this process should be very attractive to the possible industrial application for the functionalization of arenes.

Journal Article↗
PubMed2000

Nodal basin recurrence following lymph node dissection for melanoma: implications for adjuvant radiotherapy.

PURPOSE: To analyze patterns of failure in malignant melanoma patients with lymph node involvement who underwent complete lymph node dissection (LND) of the nodal basin. To determine prognostic factors predictive of local recurrence in the lymph node basin in order to select patients who may benefit from adjuvant radiotherapy. METHODS AND MATERIALS: A retrospective analysis of 338 patients undergoing complete LND for melanoma between 1970 and 1996 who had pathologically involved lymph nodes was performed. Mean follow-up from the time of LND was 54 months (range: 12-306 months). Lymph node basins dissected included the neck (56 patients), axilla (160 patients), and groin (122 patients). Two hundred fifty-three patients (75%) underwent therapeutic LND for clinically involved nodes, while 85 patients (25%) had elective dissections. Forty-four percent of patients received adjuvant systemic therapy. No patients received adjuvant radiotherapy to the lymph node basin. RESULTS: Overall and disease-specific survival for all patients at 10 years was 30% and 36%, respectively. Overall nodal basin recurrence was 30% at 10 years. Mean time to nodal basin recurrence was 12 months (range: 2-78 months). Site of nodal involvement was prognostic with 43%, 28%, and 23% nodal basin recurrence at 10 years with cervical, axillary, and inguinal involvement, respectively (p = 0.008). Extracapsular extension (ECE) led to a 10-year nodal basin failure rate of 63% vs. 23% without ECE (p < 0.0001). Patients undergoing a therapeutic dissection for clinically involved nodes had a 36% failure rate in the nodal basin at 10 years, compared to 16% for patients found to have involved nodes after elective dissection (p = 0.002). Lymph nodes larger than 6 cm led to a failure rate of 80% compared to 42% for nodes 3-6 cm and 24% for nodes less than 3 cm (p < 0.001). The number of lymph nodes involved also predicted for nodal basin failure with 25%, 46%, and 63% failure rates at 10 years for 1-3, 4-10, and > 10 nodes involved (p = 0.0001). There was no significant difference in nodal basin control in patients with synchronous or metachronous lymph node metastases, nor in patients receiving or not receiving adjuvant systemic therapy. Nodal basin failure was predictive of distant metastasis with 87% of patients with nodal basin recurrence developing distant disease compared to 54% of patients without nodal failure (p < 0.0001). On multivariate analysis, number of positive nodes and type of dissection (elective vs. therapeutic) were significant predictors of overall and disease-specific survival. Size of the largest lymph node was also predictive of disease-specific survival. Site of nodal involvement and ECE were significant predictors of nodal basin failure. CONCLUSIONS: Malignant melanoma patients with nodal involvement have a significant risk of nodal basin failure after LND if they have cervical involvement, ECE, >3 positive lymph nodes, clinically involved nodes, or any node larger than 3 cm. Patients with these risk factors should be considered for adjuvant radiotherapy to the lymph node basin to reduce the incidence of nodal basin recurrence. Patients with nodal basin failure are at higher risk of developing distant metastases.

Adult↗
PubMed2000

p53 and P-glycoprotein expression are significant prognostic markers in advanced head and neck cancer treated with chemo/radiotherapy.

The development of biological markers of response to chemo- and radiotherapy to judge benefit to risk ratios for toxic treatments is still at an experimental stage. Tumour cell death is largely by apoptosis and the p53 gene has a major influence on this. P-glycoprotein (P-gp) accumulation has been correlated with treatment failure in several types of cancer. p53 and P-gp expression were studied in 111 advanced head and neck cancers treated with radiotherapy and up to four courses of synchronous or sequential chemotherapy. The probability of survival at 5 years for patients in the trial as a whole was 27.7%, while the cohort used for this marker project was 29.4%. Among the subjects used for the marker study at the time of analysis, 13 remained disease-free and 18 were alive. Immunohistochemistry was used to assess p53 and P-gp expression; 27/111 (24%) head and neck cancers demonstrated p53/P-gp expression and 33/111 (30%) were both p53- and P-gp- negative. In univariate analysis, both p53 and P-gp expression were associated with reduced disease-free and overall survival. Multivariate analysis revealed tumour size, p53, and P-gp expression as the most powerful pretreatment prognosticators in the study cohort. Long-term follow-up results suggest that p53 and P-gp co-expression predicts the biological behaviour or the outcome following chemo/radiotherapy in advanced head and neck cancer.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

[Hemorrhagic shock increases the occurrence of bacterial translocation].

OBJECTIVE: To determine whether hemorrhagic shock (HS) increases the occurrence of bacterial translocation (BT). METHODS: 100 patients were divided into 4 groups: control group (group I, 34 patients); group with hemorrhagic shock (HS) caused by closed blunt abdominal trauma (group II, 23); group caused by closed blunt abdominal trauma without HS (group III 15); and group with HS caused by intra-abdominal viscus hemorrhage (group IV 28). Preoperative and postoperative samples were taken from peripheral blood, visceral peritoneal swab, portal vein blood, ileal mesenteric lymph node, liver and spleen biopsy respectively for aerobic and anaerobic culture. RESULTS: The positive culture rates of these groups were 6%, 65%, 13%, 68% respectively. The difference between the control and experimental groups was significant(P < 0.05). The difference was also significant between group I and II and between I and IV (P < 0.01), whereas it was not significant between I and III, and between II and IV (P > 0.05). CONCLUSION: HS increases the occurrence of BT.

Abdominal Injuries↗
PubMed2000

[The effect of hyperoxic solution on acute myocardial hypoxia in scalded rabbits].

OBJECTIVE: To investigate the effects of hyperoxic solution on acute myocardial hypoxia in scalded rabbits. METHODS: Rabbits inflicted with 30% TBSA III degree scald injury and/or acute myocardial ischemia were employed as the model. Animals were randomly divided into 4 groups, i.e. scalded rabbits treated with hyperoxic solution (A), scalded rabbits treated with normal saline (B), scalded rabbits without any treatment (C(b)) and normal healthy rabbits (C(h)). The cardiac function, blood rheology, blood gas analysis and the ratio of infarction to ischemic areas were dynamically monitored. RESULTS: (1) The cardiac function of the rabbits in B group was evidently worse than that in C(h) group (P < 0.01) and A group (P < 0.05). (2) The whole blood viscosity in A, C(b) and especially B groups was obviously increased compared with that in C(h) group (P < 0.05). While the viscosity in A group was much lower than that in B group (P < 0.01), it was similar to that in C(b) group (P > 0.05). (3) The PO(2) in A group was significantly higher than that in B and C (C(b), C(h)) groups (P < 0.01). (4) The ratio of infarction to ischemic areas in A group was remarkably lower than that in B group (P < 0.01). CONCLUSION: The hyperoxic solution may exert beneficial effects on acute myocardial ischemia in scalded rabbits. The mechanism might be related to the immediate correction of hypoxia in vital organs with simultaneous lowering of blood viscosity and the establishment of myocardial collateral circulation after the infusion of hyperoxic solution.

Animals↗
PubMed2000

[The influence of hTGFbeta(1) gene transfection on the proliferation of NIH 3T3 fibroblast].

OBJECTIVE: To investigate the influence of hTGFbeta(1) ene transfection on the proliferation of in vitro cultured NIH 3T3 fibroblast. METHODS: Lipofictin mediated co-transfected method was employed to transfect hTGFbeta(1) plasmid DNA into NIH 3T3 fibroblasts of the rats. Cell growth counting method, MTT, flow cytometry (FCM) and soft agar clone forming method were adopted to examine the biology of the transfected cells. RESULTS: (1) Fibroblast growth slowed down after hTGFbeta(1) transfection, especially on 4th to 6th days after the transfection, which was accompanied by decreased synthesis of DNA as indicated by the increase of G(1) phase percentage (from 39.9% to 66.2% P < 0.05) and the decrease of S phase percentage (from 40.2% to 26.8%, P < 0.05); (2) There was no evident change of all the phases in a cell cycle in the blank load transfection group and in control group. (3) There was a good correlation between MTT and cell counting method (co-efficient 0.992) (4) The formation rate of the soft agar clone of fibroblast decreased from 1.18% to 0.55% (P < 0.05) after hTGFbeta(1) transfection. CONCLUSION: hTGFbeta(1) gene transfection could inhibit fibroblast proliferation, which might be related to the interference of TGFbeta(1) with the DNA synthesis of fibroblasts.

3T3 Cells↗
PubMed2000

[Simultaneous spectrophotometric determination of trace ferrum and cobalt with 5-Br-PADAP and Tween-80].

A new simultaneous method for the determination of ferrum and cobalt with 5-Br-PADAP by spectrophotometry in the presence of Twen-80 is studied. The results showed that in pH = 3.4 HAc-NaAc buffer medium, ferrum and cobalt can formed colored complexes with 5-Br-PADAP. Its maximum absorption wavelengths are at 585 nm. Beer's law is obeyed for the concentration of ferrum in the range of 0-10 micrograms.25 mL-1 and 0-12 micrograms.25 mL-1 of cobalt. The apparent molar absorptivities are epsilon 585Fe = 7.18 x 10(4) and epsilon 585Co = 9.27 x 10(4) respectively. This method has been applied to the determination of ferrum and cobalt in water sample with satisfactory results.

Azo Compounds↗
PubMed1999

Synaptic organization and neurotransmitters in the rat accessory olfactory bulb.

The accessory olfactory bulb (AOB) is the first relay station in the vomeronasal system and may play a critical role in processing pheromone signals. The AOB shows similar but less distinct lamination compared with the main olfactory bulb (MOB). In this study, synaptic organization of the AOB was analyzed in slice preparations from adult rats by using both field potential and patch-clamp recordings. Stimulation of the vomeronasal nerve (VN) evoked field potentials that showed characteristic patterns in different layers of the AOB. Current source density (CSD) analysis of the field potentials revealed spatiotemporally separated loci of inward current (sinks) that represented sequential activation of different neuronal components: VN activity (period I), synaptic excitation of mitral cell apical dendrites (period II), and activation of granule cells by mitral cell basal dendrites (period III). Stimulation of the lateral olfactory tract also evoked field potentials in the AOB, which indicated antidromic activation of the mitral cells (period I and II) followed by activation of granule cells (period III). Whole cell patch recordings from mitral and granule cells of the AOB supported that mitral cells are excited by VN terminals and subsequently activate granule cells through dendrodendritic synapses. Both CSD analysis and patch recordings provided evidence that glutamate is the neurotransmitter at the vomeronasal receptor neuron; mitral cell synapses and both NMDA and non-NMDA receptors are involved. We also demonstrated electrophysiologically that reciprocal interaction between mitral and granule cells in the AOB is through the dendrodendritic reciprocal synapses. The neurotransmitter at the mitral-to-granule synapses is glutamate and at the granule-to-mitral synapse is gamma-aminobutyric acid. The synaptic interactions among receptor cell terminals, mitral cells, and granule cells in the AOB are therefore similar to those in the MOB, suggesting that processing of chemosensory information in the AOB shares similarities with that in the MOB.

Animals↗