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Biomedical subjects

Q Cao

Publications and source records attributed to Q Cao.

At least 73 records · Page 4Linked to original sources
PubMed1998

[Application of comparative genomic hybridization to hyperdiploid acute lymphoblastic leukemia].

OBJECTIVE: To evaluate the implication of comparative genomic hybridization (CGH) in leukemia study. METHODS: Genomic abnormalities in 14 ALL patients were assayed by CGH, and the results were compared with those of conventional karyotype analysis. RESULTS AND CONCLUSION: Regional and/or whole chromosome over-representation was found to be more frequent than under-representation (43 gains versus 6 losses), the most common gains involved being chromosomes 21 and X. Comparison between the results of CGH and conventional R-banding analysis showed that: 1. In 2 cases with trisomy, both the methods gave identical results. 2. In 8 cases, both the results were consistent excepting for minor discrepancies. 3. In 3 cases, including 2 each with triploidy and tetraploidy respectively, and one with chimeric karyotype of normal/+22, the results from the two methods were discrepant.

Adolescent↗
PubMed1998

[Surgical treatment of aortopulmonary septal defect].

OBJECTIVE: To study the surgical treatment of aortopulmonary septal defect. METHOD: From January 1983 to December 1996, 5 patients with aortopulmonary septal defect (APSD) (2 male and 3 female) aged from 6 to 34 years (mean 17.4 years) underwent surgical treatment. According to Mori's were classification, 5 patients belonged to type I, 2 type II and 1 type III. The diameters of the defect ranged from 1.0 to 3.0 cm. The operations were performed under moderate hypothermic cardiopulmonary bypass. Pulmonary artery incision was performed, in 3 patients while aortic incision in the other 2. All defects were repaired by Dacron patch. RESULT: There were no operative deaths and postoperative complications. During follow-up of 10 months to 12 years, no late complications and deaths were found. CONCLUSION: The operation should be done early as possible whenever the diagnosis is established. The surgical repair should be taken under cardiopulmonary bypass. To chose an incision on the aorta is more reasonable than on the pulmonary artery. The use the dacron patch can prevent stenosis and recanalization after operation.

Adolescent↗
PubMed1998

[Modulation of cGMP levels, soluble guanylate cyclase and phosphodiesterase activities in brain of morphine-dependent mice].

By inducing morphine dependence in mice, the changes of cGMP contents, phosphodiesterase (PDE) and soluble guanylate cyclase (sGC) activities and their phosphorylation regulated by protein kinase A (PKA) were observed. It was found that: (1) cGMP contents in cerebellum, striatum, hippocampus and cerebral cortex were significantly lower. (2) The sGC activities were apparently decreased in cerebellum and striatum. In the striatum and cerebral cortex the sGC activities and phosphorylation levels in vitro were significantly increased and were inhibited by PKA inhibitor. (3) The PDE activities showed no change in cerebellum and hippocampus, but in striatum and cerebral cortex PDE activities and phosphorylation levels in vitro were significantly increased and were inhibited by PKA inhibitor. (4) These changes described above were not observed in mice treated with naloxone 30 min prior to daily morphine injection. Our data indicate that the decrease of cGMP contents occurred generally in brain regions of morphine-dependent mice. The decrease of cGMP contents in cerebellum and hippocampus may be due to the decrease of sGC activities, but the decrease of cGMP contents in striatum and cerebral cortex may be mainly due to the increase of PDE activity. Both sGC and PDE activities were regulated by PKA.

Animals↗
PubMed1998

Decreased tumor necrosis factor-alpha and interleukin-1alpha production from intrahepatic mononuclear cells in chronic ethanol consumption and upregulation by endotoxin.

The relationship between the changes in liver pathology and the production of interleukin (IL)-1alpha, IL-6, and tumor necrosis factor-alpha (TNF-alpha) by intrahepatic mononuclear cells was studied in rats fed alcohol and subsequently exposed to lipopolysaccharide (LPS). Rats were fed 40% ethanol in drinking water, whereas control rats were provided with a chow diet with isocaloric or 2% sucrose drinking solutions for up to 20 weeks. Decreased IL-1alpha and TNF-alpha production in 24-hr culture supernatants of mononuclear cells isolated from liver perfusate was detected while IL-6 remained unchanged over 20 weeks. When animals were injected with LPS (1.0 microg/kg body weight), there was a 5-fold rise in ALT levels in the ethanol-fed group, but not in control groups. Increased IL-6 and TNF-alpha levels in the serum and supernatant of cultured intrahepatic mononuclear cells stimulated with or without LPS or concanavalin A was observed. There was a correlation between levels of ALT and TNF-alpha, but not IL-6. T cells and Kupffer cells were the major source of TNF-alpha in culture supernatants of hepatic perfusate mononuclear cells from ethanol-consuming rats injected LPS. In addition, pathological liver injury was evident, which suggests a pathogenic role for TNF-alpha in alcohol-induced liver disease.

Animals↗
PubMed1998

Altered T-lymphocyte responsiveness to polyclonal cell activators is responsible for liver cell necrosis in alcohol-fed rats.

The role of T-cell activation in alcoholic liver disease was investigated in rats fed alcohol and subsequently exposed to concanavalin A (Con A). Following Con A injection (20 mg/kg body weight), greater increases in liver-to-body weight ratio and ALT levels were observed at 12 and 24 hr in rats fed ethanol, compared with control rats fed sucrose. Furthermore, increases in serum interleukin-6 and tumor necrosis factor-alpha levels were noted in ethanol-fed rats, with maximal levels detected at 4 hr declining thereafter, but remaining above control levels at 24 hr. Analysis of T-cell subpopulations showed an increased percentage of CD4+, CD5+, and CD8+ T cells in blood from all groups, but not in liver perfusate. In contrast, a significant increase in the percentage of activated CD25+ T cells was detected in both blood and liver perfusate from rats fed ethanol even 24 hr after Con A injection. When CD4+ and CD8+ T cells from liver perfusate were cultured in the absence or presence of Con A, an increase in interleukin-6 and tumor necrosis factor-alpha production in supernatants was observed in ethanol-fed rats. In cultures stimulated with Con A, a 2- to 8-fold increase in cytokine production was detected, with intrahepatic CD4+ T cells being the major source. Immunohistological analysis revealed infiltration of CD4+ T cells around portal vein and central vein areas associated with fatty liver and severe hepatic necrosis. The results suggest that alcohol consumption induced a dysregulated T-cell population that mediated hepatic necrosis following polyclonal activation with Con A.

Animals↗
PubMed1998

[Studies on complex chromosomal translocation and their relevance to clinical prognosis in acute promyelocytic leukemia].

OBJECTIVE: To study the relationship between the complex chromosome translocation in acute promyelocytic leukemia(APL, M3) and clinical therapy and prognosis. METHODS: Chromosome translocation and PML-RAR fusion transcript in three APL patients were studied by using karyotypic analysis, fluorescence in situ hybridization and reverse transcriptase/polymerase chain reaction. RESULTS: The findings revealed that all these cases had PML/RAR A gene rearrangement. Apart from the chromosomes 15 and 17 involved in the translocation, other multiple chromosomes including 5, 11, 16, 22 were also implicated in complex translocations, which to some extent seemed to be related with clinical prognosis. CONCLUSION: This study provides additional information for monitoring clinical therapy and prognostic evaluation.

Adult↗
PubMed1997

Suggestive evidence for a schizophrenia susceptibility locus on chromosome 6q and a confirmation in an independent series of pedigrees.

We have investigated whether there is a locus on chromosome 6 that confers an increased susceptibility to schizophrenia using a two-stage approach and nonparametric linkage analysis. Allele sharing identical by descent (IBD) and multipoint maximum likelihood score (MLS) statistics were employed. Results from two tested data sets, a first data set, or genome scanning data set, and a second replication data set, show excess allele sharing for multiple markers in 6q, a chromosomal region not previously reported as linked to schizophrenia. In our genome scanning data set, excess allele sharing was found for markers on 6q13-q26. The greatest allele sharing was at interval 6q21-q22.3 at marker D6S416 (IBD percentage 69; P = 0.00024). The multipoint MLS values were greater than 2.4 in the 11.4-cM interval delimited by D6S301 and D6S303, with a maximum value of 3.06 close to D6S278 and of 3.05 at D6S454/D6S423. We did not confirm, however, the previously described linkage in 6p, when tested in the systematic genome scanning data set. The replication data set also showed excess allele sharing in chromosomal area 6q13-q26, which overlapped with the aforementioned positive linkage area of the genome scanning data set. The highest sharing of the second data set was at D6S424 (IBD percentage 64; P = 0.0004), D6S283 (IBD percentage 62; P = 0.0009), and D6S423 (IBD percentage 63; P = 0.0009). Multipoint MLS analysis yielded MLS values greater than 1 in an area of about 35 cM, which overlaps with the MLS multipoint area of linkage from the genome scanning data set. The multipoint MLS at the D6S454/D6S423 locus was 2.05. In the second data set, the maximum multipoint MLS was located about 10 cM centromeric from the maximum of the genome scanning data set, at the interval D6S424-D6S275 (2.35). Our results provide very suggestive evidence for a susceptibility locus for schizophrenia in chromosome 6q from two independent data sets.

Alleles↗
PubMed1997

Effects of mutations in Pr160gag-pol upon tRNA(Lys3) and Pr160gag-plo incorporation into HIV-1.

During HIV-1 viral assembly, both Pr160gag-pol and primer tRNA(Lys3) are packaged into the virus. tRNA(Lys) packaging (both tRNA(Lys3) and tRNA(Lys1,2) is dependent upon the presence of RT sequences within Pr160gag-pol. In this work, we have monitored the effect of Pr160gag-pol mutations upon incorporation of tRNA(Lys3) and Pr160gag-pol into HIV-1 produced from COS-7 cells transfected with mutant HIV-1 proviral DNAs. Mutations include carboxy deletions of Pr160gag-pol and small amino acid insertions and replacements within the various functional domains of the reverse transcriptase (RT). tRNA(Lys3) incorporation was monitored both by 2D PAGE of viral RNA, and by hybridization with tRNA(Lys3)-specific DNA probes. Our data indicates: (1) deletion of integrase sequence has a moderate effect upon select tRNA(Lys3) packaging, while carboxy terminal deletions extending further into the RNase H and connection domains more strongly reduce viral tRNA(Lys3) content; (2) tRNA(Lys3) incorporation is strongly reduced by small inframe amino acid insertions or replacements in the carboxy region of the thumb domain and the amino half of the connection domain of RT, but tRNA(Lys3) incorporation is altered little, or not at all, by similar amino acid insertional mutations within other RT domains, such as the fingers, palm, RNase H, the amino portion of the thumb, and the carboxy region of the connection domain. The inability of connection domain mutant virus to incorporate tRNA(Lys3) and to properly process precursor proteins in the virus is due to the inability of mutant Pr160gag-pol to be incorporated into the virus. These mutant precursor proteins are maintained at levels in the cytoplasm similar to wild-type.

Animals↗
PubMed1997

No abnormality in the gene for the G protein stimulatory alpha subunit in patients with bipolar disorder.

BACKGROUND: The available evidence for an involvement of the heterotrimeric guanine-nucleotide-binding proteins (G proteins) in bipolar disorder relies primarily on the effects of lithium salts on G protein function and on alterations in the concentration or function of G proteins (most notably Gs-alpha) in peripheral leukocytes and in postmortem tissues of patients with bipolar disorder. METHODS: The hypothesis that a mutation in Gs-alpha gene confers an increased susceptibility to bipolar disorder was tested by the following strategies: (1) mutational screening of the Gs-alpha subunit gene coding sequences and promoter sequences by denaturing gradient gel electrophoresis in unrelated individuals with bipolar disorder and (2) association and linkage analyses with a common silent exonic polymorphism, using genetic allelic information from American families with at least 1 affected child. For association analysis, the transmission test for linkage disequilibrium was used; for linkage analysis, nonparametric methods were used. RESULTS: No structural or regulatory mutations in this gene were found in bipolar disorder; the results of association and genetic linkage were negative. CONCLUSION: Our results do not support the speculation that the Gs-alpha protein gene has a role in the genetic predisposition to bipolar disorder.

Base Sequence↗
PubMed1997

[Detection of MLL gene rearrangement in acute myelomonocytic and monocytic leukemia].

OBJECTIVE: To reveal the incidence of MLL gene rearrangement and its clinical, features in acute myelomonocytic leukemia (M4) and acute monocytic leukemia (M5). METHODS: 10 patients with M4 and 27 cases with M5 were studied with the Southern blot technique to detect MLL gene abnormalities. RESULTS: 5 M5 patients were found to have MLL rearrangement, and these patients were characterized clinically by: (1) Younger at onset, (2) a higher white blood cell count (often > 100 x 10(9)/L), (3) frequent extramedullary involvement with hepatosplenomegaly and central nervous system leukemia (CNSL), and (4) a lower remission rate with a short survival time. CONCLUSION: There is a high incidence of MLL rearrangement in M5, and this gene abnormality stands for a marker of poor prognosis.

Adolescent↗
PubMed1997

[Detection of bcr gene rearrangement in chronic myeloid leukemia by fluorescence in situ hybridization].

OBJECTIVE: To detect bcr gene rearrangement in chronic myeloid leukemia (CML). METHODS: Bcr rearrangement was detected by fluorescence in situ hybridization (FISH), using 765E3, a yeast artificial chromosome (YAC)-derived probe flanking the breakpoint within bcr gene. RESULTS: Nine patients with CML were examined, bcr gene rearrangement was revealed in 5 cases in chronic phase, 2 in blastic phase, and one after interferon-alpha therapy. The karyotype of 1 case after autologous bone marrow transplantation (ABMT) was chimera with normal and bcr gene rearrangement chromosomes. CONCLUSION: YAC765E3 is a useful probe for detecting bcr gene rearrangement. FISH technique is likely an important tool for monitoring of treatment and revealing minimal residual disease in CML.

Chromosomes, Artificial, Yeast↗
PubMed1997

Biological and clinical significance of cytogenetic study on 100 acute lymphoblastic leukemia and 219 acute non-lymphoblastic leukemia.

OBJECTIVE: To further investigate the role that cytogenetic may play in the diagnosis and prognosis of leukemia, a study was conducted in 319 acute leukemias. METHODS: 100 patients with acute lymphoblastic leukemia (ALL) and 219 patients with acute non-lymphoblastic leukemia (ANLL) were from Rui Jin Hospital, Xin Hua Hospital, Ren Ji Hospital and Shanghai Children's Hospital. Their cytogenetic data were analyzed together with those of morphology, immunology and clinical prognosis. RESULTS: In ALL group, 48 cases were karyotypically normal whereas 52 cases revealed chromosomal changes, among which 32 had quantitative abnormalities and 20 had qualitative abnormalities. The translocation t(9; 22) was identified in 11 out of 20 cases of structural aberrations (55%). Specific structural aberrations t(9; 22) and t(8; 14) were detected to be related to B-lineage associated differentiation antigens and t(8; 14) also with ALL-L3 according to FAB classification. With regard to clinical prognosis, the survival rate of structural aberration subset decreased significantly compared with the normal karyotype subset (P < 0.05). However, no statistically significant difference was found between hyperdiploidy subset (not including near-triploidy) and normal karyotype subset (P > 0.75). In ANLL group, 80% of de novo patients and relapsed patients had chromosomal abnormalities. Importantly, structural aberrations accounted for 73% of these abnormalities and frequently corresponded to specific types of FAB classification. Relevant prognostic studies demonstrated that t(15; 17) subset had the best overall survival probability, followed by t(8; 21) and normal karyotype subset, while the numerical aberration subset showed a relatively poor prognosis. CONCLUSION: Our data confirmed that cytogenetic study is important for the molecular study of the leukemogenesis. On the other hand, it also provides an independent parameter for prognosis in acute leukemia.

Adolescent↗
PubMed1996

Long-term follow-up of minimal residual disease in childhood acute lymphoblastic leukemia patients by polymerase chain reaction analysis of multiple clone-specific or malignancy-specific gene markers.

Two types of markers, namely the clone-specific markers including T-cell receptor (TCR) gamma, TCR delta, and Ig heavy-chain (IgH) gene rearrangements, and malignancy-specific fusion gene mRNA such as SIL-TAL-1, BCR-ABL, and HRX-partner genes, were investigated by molecular biology techniques in 65 Chinese patients with acute lymphoblastic leukemia (ALL). In combination, these markers were informative among 96% of patients. Minimal residual disease (MRD) was followed up in 23 of these patients with available materials over a period varying from 8 to 54 months with at least one leukemia-specific probe. In most children, MRD was decreased continuously to an ultimately undetectable level within 6 to 12 months after remission induction therapy. One patient exhibited low-level residual leukemic cells for 4 years before the MRD turned negative. Another patient remained in complete remission for 45 months, although a positive signal was detected at 34 months using TCR delta probe, but was negative with a TCR gamma marker which was positive at presentation. In three patients who relapsed, MRD either persisted through the clinical course or became positive and eventually increased 3-11 months before clinical relapse. These data suggested that the combined use of multiple gene markers is a valuable tool for the PCR-based MRD detection, since it can cover most ALL patients. Furthermore, long-term follow-up of MRD is helpful for determining the dosage as well as the period of maintenance chemotherapy and for predicting impending relapse.

Base Sequence↗
PubMed1996

[Influence of neuronal excitation and inhibition of rostral ventrolateral medulla on the effect of electroacupuncture of "Neiguan" acupoint].

Experiments were performed on 44 rabbits anesthetized with a mixture of urethane and chloralose. The effects of microinjection of glutamate and glycine in bilateral rostral ventrolateral medulla (rVLM) on the reaction of electroacupuncture (EA) of "Neiguan" acupoint (PC 6) after myocardial ischemia by ligature of the left ventricular branch of coronary artery were observed. Results showed that (1) EA could significantly promote the recovery of ECG ST-segments, mean blood pressure (MBP), left ventricular pressure (LVP) and the maximum rising rate of LVP (dp/dt max); (2) Glutamate could enhance the effects of EA on MBP, LVP and dp/dt max to a certain extent; (3) The effects of EA could be weakened significantly by glycine. It suggests that EA-induced improvement of the cardiovascular function can be strengthened further in some degree when neurons of rVLM are excited and weakened pronouncedly while the neurons are inhibited. Therefore, rVLM participates in the regulatory process of EA on functional activity of the heart.

Acupuncture Points↗
PubMed1996

[Influence of microinjection of clonidine and yohimbine in rVLM on the effect of electroacupuncture treatment of myocardial ischemia].

In the present paper, influence of microinjection of clonidine (Clon, 0.38 mMol, 2 microliters) and yohimbine (Yoh, 5.1 mMol, 2 microliters) in rostral ventrolateral medulla (rVLM) on the effect of electroacupuncture (EA) at Neiguan (PC 6) was observed in the rabbit with acute myocardial ischemia. Results showed that (1) EA of Neiguan could significantly accelerate the recovery of AMI-induced changes in ECG ST-segement, mean blood pressure, left ventricular pressure (LVP) and dp/dt max; (2) Clon strengthened the effect of EA on ST and LVP in some degree; and (3) Yoh significantly weakened the effect of EA on ST and LVP. It reveals that when alpha 2 receptors of rVLM are excited, the favourable effect of EA in regulating post-ischemic myocardial electrical and mechanical activity can be enhanced in some degree; and when they are inhibited, the effect of EA disappears, indicating an involvement of alpha 2 receptors of rVLM in EA of Neiguan-induced regulation on the functional activity of the heart.

Adrenergic alpha-Agonists↗
PubMed1995

[Study of subcuticular suture skill for perineotomy and catgut-suture reaction].

The post perineotomy complications such as catgut-suture-reaction, incision infection, and laceration are very common in the hospital. The purpose of this study was to find a better suture skill. The subcuticular suture skill was studied in this study. The relationship between suture skill and catgut suture reaction was analysed. 200 women had vaginal delivery with perineotomy subcuticular suture who were hospitalized during 3 to 10 in 1994 were compared with 399 women with perineotomy routine suture skill who were hospitalized during the same period in 1992 and 1993. The result indicated that the incidence of cat gut suture reaction and secondary suture in the research group were 9%, 7.5% lower than that in control group (P < 0.01). The average time of hospitalization was 5.3 days shorter (P < 0.025). These implicate the future study on perioneotomy suture skill.

Catgut↗