Biomedical subjects

Hua Liang

Publications and source records attributed to Hua Liang.

At least 19 recordsLinked to original sources

PubMed2006

Immune responses to vaccinia and influenza elicited during primary versus recent or distant secondary smallpox vaccination of adults.

The kinetics and frequency of the primary response to human smallpox vaccine was compared to that among subjects re-vaccinated within the last 2 years, or after several decades. Vaccination induced local and systemic reactions that were mildest in the distant cohort and more severe in the primary vaccinees. The timing of IFN-gamma responses was similar in all three groups, but of higher frequency in the primary vaccinees. Responses to vaccinia re-immunization between those immunized <2 years ago and those immunized >10 years ago were not significantly different. Neutralizing antibodies were boosted in all groups, with the highest titers observed among the distant cohort. However, the antibody and IFN-gamma responses did not correlate strongly with the local reactions at the vaccine site. This suggests that local immune events in the tissue are distinct from the parameters measured in the peripheral blood.

Adolescent↗

PubMed2006

Comparison of antitumor activities in tumor xenograft treatment.

To compare treatment effects with antitumor therapies, we proposed an intuitive approach to compare the antitumor effects of two different antitumor treatments by investigating tumor volumes which were measured in a given period of time. The approach is, in essence, a comparison of two unknown functions. The implementation of the approach is simple and straightforward. The approach is applied to analyze a real xenograft study of a new antitumor agent, irofulven, combined with irinotecan.

Algorithms↗

PubMed2006

Increased influenza vaccination of healthcare workers at a pediatric cancer hospital: results of a comprehensive influenza vaccination campaign.

A comprehensive influenza vaccination campaign improved vaccination rates among healthcare workers with direct patient care responsibilities from 45% during the 2003-2004 influenza season to 80% during the 2004-2005 season. A strategy of weekly feedback to unvaccinated employees was the most important factor in enhancing the rate of vaccination acceptance and was particularly effective among the nursing staff.

Cancer Care Facilities↗

PubMed2006

A new method of evaluating antitumor activity from measured tumor volumes.

In studies of antitumor activity, measurement of tumor growth delay is commonly used to evaluate treatment effects. However, this measurement sometimes provides no information. We propose an approach for comparing tumor response by using nonparametric regression. In a xenograft model, we found that a significant difference between two treatment effects was undetectable by comparison of tumor growth delays. The results of our finding suggest that measurements used to evaluate the treatment effects should be carefully selected in analyses of antitumor activity.

Animals↗

PubMed2006

Checking linearity of non-parametric component in partially linear models with an application in systemic inflammatory response syndrome study.

Two tests are proposed for checking the linearity of nonparametric function in partially linear models. The first one is based on a Crámer-von Mises statistic. This test can detect the local alternative converging to the null at the parametric rate 1/square root n. A bootstrap resample technique is provided to calculate the critical values. The second one is constructed in a penalized spline framework along with linear mixed-effects (LME) modeling. This is an extension likelihood ratio test for testing zero variance of random effects in LME models. Simulation experiments are conducted to explore the numerical performance of two tests. It is observed that two tests have good level properties, and the first test has a substantially superior power property over the second test in a variety of cases. A real data set is analysed with the proposed tests.

Humans↗

PubMed2006

[Induction of EIAV-specific cellular immune response by attenuated EIAV vaccine].

AIM: To elucidate cellular immune protective mechanism of EIAV. METHODS: Four horses were immunized with (DLV) by subcutaneous injection and 2 horses with 0.85% sodium chloride as the negative control. Rectal temperatures and clinical features were recorded daily. Whole blood samples were collected, from which PBMC were separated and used for CTL assay and lymphocyte proliferation assay. RESULTS: The target cells were activated by PWM and treated with DLV or recombinant vaccinia vectors expressing DLV and LN Gag or Env separately. The percentage of EIAV-specific CTL lysis was under 5% in the negative control group, however, that was 20% to 30% in the group of immunized horses. The stimulation index (SI) from proliferation assay was 3 in the group immunized with attenuated DLV vaccine. CONCLUSION: The results indicated that EIAV-specific cellular immune-response induced by DLV immunization may contribute to the immune protective effect against EIAV virus infection.

Animals↗

PubMed2006

[Effects of preoperative acute hypervolemic hemodilution on hypercoagulability of patients with colon cancer].

BACKGROUND & OBJECTIVE: Cancer patients have an increased risk of thrombosis after operation because of a hypercoagulable status. Therefore, anticoagulant treatment is necessary for patients with hypercoagulability during perioperative period. This study was to investigate the effect of acute hypervolemic hemodilution (AHHD) with 6% hydroxyethyl starch (HES), or 4% succinylated gelatin (GEL), or lactated Ringer's (RL) solution before operation on the hypercoagulable status and the occurrence of deep venous thrombosis (DVT) of patients with colon cancer. METHODS: Sixty colon cancer patients with hypercoagulable status underwent operation were randomized into HES, GEL, and RL groups; each group contained 20 patients. The patients were infused with HES, GEL, or RL solution respectively at a dose of 15 ml/kg within 30 min before operation. Preoperative coagulation function was assessed by thrombelastography (TEG). DVT was diagnosed by the color Doppler ultrasonic system. RESULTS: Acute hypervolemic hemodilution with HES solution led to a significant decrease of coagulation index (CI) at 30 min and 2 h after starting operation and 1 h after operation as compared with the prehemodilution value (P<0.01). At 1 h after operation, CI was significantly lower in HES group than in GEL group (P<0.05). At 30 min and 2 h after starting operation and 1 h after operation, CI was significantly lower in HES group than in RL group (P<0.05). Hemodilution with GEL solution lessened CI at 30 min and 2 h after starting operation significantly as compared with the prehemodilution value (P<0.01). At 30 min and 2 h after starting operation, CI was significantly lower in GEL group than in RL group (P<0.05). After operation, DVT in occurred 2 (10%) patients in HES group, 3 (15%) in GEL group, and 10 (50%) in RL group (P<0.05). CONCLUSION: Acute hypervolemic hemodilution with HES solution and GEL solution can alleviate the hypercoagulability of colon cancer patients during perioperative period and decrease the occurrence of DVT.

Adult↗

PubMed2005

Amino acid mutations of the infectious clone from Chinese EIAV attenuated vaccine resulted in reversion of virulence.

The Chinese equine infectious anemia virus (EIAV) donkey-leukocyte attenuated vaccine (DLV) provides a unique natural model system by which attenuated mechanism and immunological control of lentivirus replication may be studied. We analyzed the critical consensus mutations that occurred during the viral passages in vitro and in vivo for vaccine's preparation. Based on the full-length infectious clone pLGFD3 (EIAV vaccine background) and according to mutations displayed during viral attenuation, we successfully constructed an infectious clones pLG5-3-l in which gag and env genes were point-mutated by overlap PCR mutagenesis strategy. pLG5-3-l was proved to have the ability of effective replication in vitro cells culture systems by Reverse Transcriptase Assay and virion observation under electron microscopy. Results of the in vivo experiments indicated that marked differences occurred between the mutated virus and their parental virus in clinical manifestation and plasma viral replication during 6-month observation period. In contrast to asymptom of animals infected with pLGFD3-V, the mutated virus (pLG5-3-l-V) developed typical clinical progression in the corresponding experimentally infected animals. The results of the distinct differences in clinical profiles and viral dynamics before and after mutation of EIAV infectious clone will help to understand the protective mechanism of Chinese EIAV vaccine and shed light on novel HIV vaccine design.

Amino Acid Substitution↗

PubMed2005

Expression of Epstein-Barr virus genes in EBV-associated gastric carcinomas.

AIM: To understand the expression of latent and lytic genes of Epstein-Barr virus (EBV) in EBV-associated gastric carcinoma (EBVaGC) and to explore the relationship between EBV-encoded genes and development of EBVaGC at molecular level. METHODS: One hundred and seventy-two gastric carcinoma tissues and 172 corresponding para-carcinoma tissues were tested for EBV genome by polymerase chain reaction (PCR)-Southern blotting. EBV-encoded small RNA (EBER) 1 of the PCR positive specimens was detected by in situ hybridization (ISH). Gastric carcinomas with positive EBER1 signals were classified as EBVaGCs. RT-PCR and Southern hybridization were applied to the detection of expression of nuclear antigen (EBNA) promoters (Qp, Wp and Cp), EBNA 1 and EBNA 2, latent membrane proteins (LMP) 1, 2A and 2B and lytic genes (immediate early genes BZLF1 and BRLF1, early genes BARF1 and BHRF1, late genes BcLF1 and BLLF1) in EBVaGCs. RESULTS: Eleven EBV positive samples existed in gastric carcinoma tissues (6.39%). No EBV positive sample was found in corresponding para-carcinoma tissues. The difference between EBV positivity in carcinoma tissues and corresponding para-carcinoma tissues was significant (chi(2) = 9.0909, P = 0.0026). Transcripts of Qp and EBNA1 were detected in all the 11 EBVaGCs, while both Wp and Cp were silent. EBNA2, LMP1 and LMP2B mRNA were absent in all the cases, while LMP2A mRNA was detected in 4 of the 11 cases. Of the 11 EBVaGCs, 7 exhibited BcLF1 transcripts and 2 exhibited BHRF1 transcripts. The transcripts of BZLF1 and BARF1 were detected in 5 cases, respectively. No BLLF1 and BRLF mRNA were detected. CONCLUSION: The latent pattern of EBV in gastric carcinoma corresponds to the latency I/II. Some lytic infection genes are expressed in EBVaGCs tissues. BARF1 and BHRF1 genes may play an important role in tumorigenesis of gastric carcinoma.

Adenocarcinoma↗

PubMed2005

Modeling antitumor activity in xenograft tumor treatment.

To analyze responses of solid tumors to treatment with antitumor therapy, we applied nonparametric mixed-effects models to investigate tumor volumes measured over a fixed. The population and individual response functions were approximated by penalized splines. Linear mixed-effects modeling was applied in the implementation of the estimation. We applied the approach to an analysis of a real xenograft study of a new antitumor agent, temozolomide, combined with irinotecan. The model fitted the data very well. We conducted a sensitivity analysis to determine the effect of informative dropout. We also propose an intuitive approach to a comparison of the antitumor effects of two different treatments. Biological interpretations and clinical implications are discussed.

Animals↗

PubMed2005

Association of LMNA 1908C/T polymorphism with cerebral vascular disease and diabetic nephropathy in Japanese men with type 2 diabetes.

OBJECTIVE: The LMNA 1908C/T polymorphism has been reported to be associated with dyslipidaemia, metabolic syndrome, adipose tissue metabolism and obesity phenotypes, suggesting that this polymorphism presents an increased risk of atherosclerosis and vascular diseases. However, there have been no previous reports on the relationship between the LMNA 1908C/T polymorphism and vascular diseases. The aim of this study therefore was to investigate the association between the LMNA 1908C/T polymorphism and the prevalence of vascular disease in Japanese patients with type 2 diabetes. DESIGN: A cross-sectional, hospital-based study of diabetic complications with an LMNA gene background. PATIENTS: One hundred and sixty-six Japanese men with type 2 diabetes. Measurements LMNA 1908C/T polymorphism (by polymerase chain reaction restriction fragment length polymorphism, PCR-RFLP); diabetic retinopathy (by standard fundus photography); diabetic nephropathy (by urinary albumin excretion rate); diabetic neuropathy (by signs, symptoms and/or nerve conduction velocity); coronary heart disease (by symptoms of typical chest pain and/or history of myocardial infarction, and ischaemic electrocardiographic alteration and/or coronary artery bypass graft surgery); cerebral vascular disease (by ultrasonography, computed tomography and/or magnetic resonance imaging). RESULTS: Carriers of the LMNA 1908T allele manifested a significantly higher prevalence of diabetic nephropathy and cerebral vascular disease than carriers of the C allele. Multiple regression analysis showed that the LMNA 1908T allele tended to be associated with cerebral vascular disease, but was independent of age, hypertension, total cholesterol or triglyceride [odds ratio (OR) 7.03, P=0.0611]. Similarly, the LMNA 1908T allele showed a significant association with diabetic nephropathy, not independent of total cholesterol or triglyceride. CONCLUSIONS: The LMNA 1908C/T polymorphism plays an important role in the development of cerebral vascular disease and diabetic nephropathy in Japanese men with type 2 diabetes.

Aged↗

PubMed2005

[The effect of kanglaite injection(KLT) on the proliferation and telomerase activity of rat mesangial cells].

OBJECTIVE: To observe the effect of Kanglaite injection(KLT) on the proliferation and telomerase activity of mesangial cells in rats. METHOD: MTT, telomere repeat amplification protocal (TRAP), ELISA, PAGE and silver-stain were applied to detect the growth rate and telomerase activity of MC after stimulation of KLT and IL-1. RESULT: The growth rate of MC was enhanced by IL-1 stimulation, which was accompanied with a redection of the activity of telomerase. Adversely, the growth rate of MC was reduced by KLT, which was accompanied with an enhancement of activity of telomerase. Moreover, the growth rate of MC and the activity of telomerase were both inhibited by the combinative use of IL-1 and KLT without any influence from the sequence of their administration. CONCLUSION: KLT could inhibit proliferation and telomerase activity of MC with or without pre-stimulation with IL-1. KLT might be useful to prevent and treat glomerular nephritis related to MC proliferation.

Animals↗

PubMed2004

Enhanced antitumor activity of irofulven in combination with irinotecan in pediatric solid tumor xenograft models.

PURPOSE: Irofulven, a novel chemotherapeutic agent with a broad spectrum of activity, is effective against preclinical models of pediatric tumors. The cytotoxic activity of irofulven is augmented when combined with agents that interact with DNA topoisomerase I; however, none of the reported studies have used the protracted dosing schedule found to be active clinically in treatment of childhood cancers. The objective of this study was to evaluate the antitumor activity of irofulven in combination with irinotecan administered on a protracted schedule in a panel of pediatric solid tumor xenografts. METHODS: Irofulven and irinotecan were evaluated alone or in combination against eight independent xenografts, which included childhood brain tumors (n=5), neuroblastoma (n=1), and rhabdomyosarcoma (n=2). Irofulven was administered i.v. daily for 5 days with courses repeated every 21 days for a total of three cycles. Doses of irofulven ranged from 1.33 to 4.6 mg/kg. Irinotecan was given i.v. daily for 5 days each week for 2 weeks repeated every 21 days for three cycles at doses between 0.28 and 1.25 mg/kg. RESULTS: Irofulven and irinotecan, given as single agents, induced few responses in pediatric solid tumor xenografts at the selected doses. At the same doses, irofulven in combination with irinotecan demonstrated superior antitumor activity, inducing complete responses in seven of the eight xenograft lines. CONCLUSIONS: These studies show that the cytotoxic activity of irofulven is greater when combined with protracted administration of irinotecan. Although the systemic exposure of irofulven required to induce objective responses in this panel of pediatric solid tumors was in excess of that achievable in patients receiving maximally tolerated doses using this schedule of drug administration, the enhanced activity of irofulven in combination with irinotecan supports the pursuit of alternative administration strategies and combinations.

Animals↗

PubMed2004

Modeling antitumor activity by using a non-linear mixed-effects model.

The response of solid tumors to antitumor treatment generally declines markedly with treatment time. Sometimes, a tumor regrows (rebounds) before the end of the treatment period. Studies of the patterns of tumor response to treatment are important, because they may provide useful information for clinical decision-making. We have investigated patterns of tumor response in mouse xenograft tumors by using data from a study conducted at St. Jude Children's Research Hospital. We applied a biexponential non-linear mixed-effects model to an analysis of changes in tumor volume over a given period of treatment. The model gives a good fit to the data, even for small sample sizes. We addressed the relation between the baseline tumor volumes and the decay rates of the first and second stages of the tumor's response to treatment, and we applied sensitive analysis to determine the effect of using different imputed values for missing data. We also proposed a novel approach to a comparison of the antitumor effects of three different treatments, and we used the data from a St. Jude study to demonstrate the potential of this comparison approach in cancer clinical decision-making.

Algorithms↗

PubMed2004

Myosin regulatory domain orientation in skeletal muscle fibers: application of novel electron paramagnetic resonance spectral decomposition and molecular modeling methods.

Reorientation of the regulatory domain of the myosin head is a feature of all current models of force generation in muscle. We have determined the orientation of the myosin regulatory light chain (RLC) using a spin-label bound rigidly and stereospecifically to the single Cys-154 of a mutant skeletal isoform. Labeled RLC was reconstituted into skeletal muscle fibers using a modified method that results in near-stoichiometric levels of RLC and fully functional muscle. Complex electron paramagnetic resonance spectra obtained in rigor necessitated the development of a novel decomposition technique. The strength of this method is that no specific model for a complex orientational distribution was presumed. The global analysis of a series of spectra, from fibers tilted with respect to the magnetic field, revealed two populations: one well-ordered (+/-15 degrees ) with the spin-label z axis parallel to actin, and a second population with a large distribution (+/-60 degrees ). A lack of order in relaxed or nonoverlap fibers demonstrated that regulatory domain ordering was defined by interaction with actin rather than the thick filament surface. No order was observed in the regulatory domain during isometric contraction, consistent with the substantial reorientation that occurs during force generation. For the first time, spin-label orientation has been interpreted in terms of the orientation of a labeled domain. A Monte Carlo conformational search technique was used to determine the orientation of the spin-label with respect to the protein. This in turn allows determination of the absolute orientation of the regulatory domain with respect to the actin axis. The comparison with the electron microscopy reconstructions verified the accuracy of the method; the electron paramagnetic resonance determined that axial orientation was within 10 degrees of the electron microscopy model.

Actins↗

PubMed2004

Heme oxygenase-1 messenger RNA expression is induced in peripheral blood mononuclear cells of pediatric cancer patients with systemic inflammatory response syndrome.

OBJECTIVE: To determine whether heme oxygenase-1 messenger RNA expression in peripheral blood mononuclear cells is induced in pediatric cancer patients with the systemic inflammatory response syndrome (SIRS) and whether this expression correlates with the heme oxygenase-1 products, bilirubin and carboxyhemoglobin. DESIGN: Prospective, controlled study. SETTING: A tertiary care pediatric oncology hospital. PATIENTS: Fourteen patients admitted to the intensive care unit with a diagnosis of SIRS by American College of Chest Physicians/Society for Critical Care Medicine consensus criteria and 17 control patients (off therapy, no acute illness). INTERVENTIONS: Blood for bilirubin, carboxyhemoglobin, and heme oxygenase-1 messenger RNA expression was collected at study entry. SIRS patients continued to have samples collected every 12 hrs for 1 wk or until intensive care unit discharge. Heme oxygenase-1, bilirubin, and carboxyhemoglobin levels of SIRS patients were compared with controls, and correlation between heme oxygenase-1 and products was assessed. MEASUREMENTS AND MAIN RESULTS: Within 48 hrs of study entry, maximum heme oxygenase-1 expression for all SIRS patients compared with controls was 5.5 +/- 1.0 vs. 1.1 +/- 0.1 (p < .0006). Maximum expression was > or =2.3-fold in 13 of 14 SIRS patients. Maximum heme oxygenase-1 expression also differed from minimum (5.5 +/- 1.0 vs. 1.6 +/- 0.3, p < .003). Maximum bilirubin and carboxyhemoglobin levels within 48 hrs of study entry differed between SIRS patients and controls (3.0 +/- 0.8 vs. 0.3 +/- 0.1, p = .006; and 1.2 +/- 0.2 vs. 0.6 +/- 0.1, p = .001, respectively). Bilirubin, but not carboxyhemoglobin, correlated with heme oxygenase-1 expression (p = .0013). CONCLUSIONS: Heme oxygenase-1 messenger RNA, bilirubin, and carboxyhemoglobin levels were increased within 48 hrs of admission in pediatric cancer patients with SIRS. Heme oxygenase-1 expression correlated with serum bilirubin levels. The increase in heme oxygenase-1 expression may add to the understanding of the increase in serum bilirubin observed in patients with SIRS/sepsis. These findings support a role for heme oxygenase-1 in the physiologic response to inflammatory stress.

Adolescent↗

PubMed2004

Association between CTLA-4 +49 A/G polymorphism and type 1B diabetes in Japanese population.

+49 A/G polymorphism of CTLA-4 gene has been suggested to be associated with type 1 diabetes in some populations. However, a functional significance of the +49 A/G polymorphism is unknown, because it is believed the polymorphism does not affect the function of the CTLA-4 molecule. In this study, we examined the +49 A/G polymorphism of the CTLA-4 gene in 30 Japanese type 1 diabetic patients (14 type 1B and 16 type 1A) and 40 non-diabetic subjects in a case-control study, and stratified patients according to genotype of the polymorphism. The distribution of genotype frequencies differed between type 1 diabetic patients and controls (p<0.01). When the subjects were subdivided into type 1A and type 1B subgroups, a significant difference in G allele frequency was found only between type 1B patients and controls, whereas G allele frequency tended to be higher in type 1A diabetic patients than controls. Type 1B patients displayed more severe metabolic decompensation (higher plasma glucose concentration, lower urinary C-peptide levels, higher insulin requirement, and higher serum amylase levels), and were found to be more prone to diabetic ketoacidosis than type 1A patients. After stratification by genotype, differences in urinary C-peptide and serum amylase levels between type 1A and type 1B patients were found to be due to differences in the GG genotype subgroup, whereas in the AG subgroup those differences disappeared. In conclusion, the +49 A/G polymorphism of CTLA-4 gene was associated with the occurrence of type 1B diabetes in a Japanese population, and type 1B diabetics with a GG genotype were associated with more severe cell dysfunction than their type 1A counterparts.

Adult↗

PubMed2004

[Expression of transforming growth factor-beta1 in renal fibrosis of human mesengial proliferative glomerulonephritis].

OBJECTIVE: To explore the possible effect of transforming growth factor-beta(1) (TGF -beta(1)) on the development of renal fibrosis in human mesengial proliferative glomerulonephritis (MsPGN). METHODS: Immunohistochemistry method, sirius red staining polarization microscopy and the computer imaging analysis system were used to detect the expression of TGF-beta(1), the distribution of collagen I, collagen III and collagen IV. RESULT: In MsPGN with renal fibrosis, collagen IV was increased markedly,and collagen I and collagen III appeared in the expanded mesengial matrix abnormally. Collagen III and collagen IV were increased markedly in tubulointerstitium. TGF-beta(1) expression was positively correlated with the expression of collagen I, collagen III and collagen IV in tubulointerstitium (r=0.82 0.92,P<0.01), and negatively correlated with I/III, I/IV and III/IV (r=-0.83,-0.92, P<0.001). CONCLUSION: Abnormal increase of TGF-beta(1) may be one of the important factors associated with glomerular sclerosis and tubulointerstitial fibrosis through the increment and abnormal distribution of collagen I, collagen III and collagen IV.

Collagen↗