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Jian Huang

Publications and source records attributed to Jian Huang.

At least 145 records · Page 8Linked to original sources
PubMed2003

Sustained reentry in the left ventricle of fibrillating pig hearts.

It has been proposed that ventricular fibrillation (VF) is driven by sustained reentry. However, mapping studies have not detected such "mother rotors" in large mammalian hearts. We mapped VF from three 21x12 unipolar electrode arrays in 6 pigs. Two of the arrays were adjacent to each other on the left-ventricular epicardium. Electrode spacing was 2 mm. The third array consisted of 21 needles (0.5-mm diameter, 12 electrodes, 1-mm spacing) inserted in a row (2-mm spacing) between the epicardial arrays. A total of 88 5-second VF epochs were analyzed with automatic reentry detection algorithms. Although intramural reentry was sporadically present (29 total occurrences), it was always short-lived with a mean life span of 127+/-57 ms. However, in 3 of the 6 animals, sustained epicardial reentry (ie, reentry persisting for more than a few cycles) was consistently present, often lasting for several seconds. For each epoch, we computed indices characterizing (1) the relative duration of reentry on the two epicardial arrays (R), (2) the flow of wavefronts between epicardial arrays (W), and (3) the relative activation rates of the two epicardial arrays (F). R did not correlate with either W or F indicating that rotor-containing regions did not produce a net outflow of wavefronts and were not faster than neighboring regions. Thus, sustained epicardial, but not intramural, rotors were consistently present in some large animal hearts during VF. However, we found no evidence that these rotors were responsible for sustaining VF through the mechanisms outlined in the mother rotor hypothesis.

Animals↗
PubMed2003

The in vitro reconstitution of nucleosome and its binding patterns with HMG1/2 and HMG14/17 proteins.

Using atomic force microscopy (AFM), the dynamic process of the in vitro nucleosome reconstitution followed by slow dilution from high salt to low salt was visualized. Data showed that the histone octamers were dissociated from DNA at 1M NaCl. When the salt concentration was slowly reduced to 650 mM and 300 mM, the core histones bound to the naked DNA gradually. Once the salt concentration was reduced to 50 mM the classic "beads-on-a-string" structure was clearly visualized. Furthermore, using the technique of the in vitro reconstitution of nucleosome, the mono- and di- nucleosomes were assembled in vitro with both HS2core (-10681 to -10970 bp) and NCR2 (-372 to -194 bp) DNA sequences in the 5 flanking sequence of human b-globin gene. Data revealed that HMG 1/2 and HMG14/17 proteins binding to both DNA sequences are changeable following the assembly and disassembly of nucleosomes. We suggest that the changeable binding patterns of HMG 14/17 and HMG1/2 proteins with these regulatory elements may be critical in the process of nucleosome assembly, recruitment of chromatin-modifying activities, and the regulation of human b-globin gene expression.

Animals↗
PubMed2003

Prevalence of overweight, obesity, and associated diseases among outpatients in a public hospital.

BACKGROUND: The prevalence of obesity is increasing and may be particularly high among indigent public hospital patients. The purpose of this study was to determine the prevalence of obesity and its associated chronic medical conditions among outpatients at Louisiana State University Health Sciences Center-Shreveport, an urban tertiary health center that serves a mostly black, indigent population. METHODS: A cross-sectional survey was conducted on 1,507 primary care patients. Age, sex, weight, height, and diagnoses were recorded, and body mass index (BMI) was calculated. RESULTS: Eighty-one percent of patients were overweight or obese and 75% had one or more obesity-associated conditions. Higher BMI was significantly associated with increased prevalence of obesity-related diseases (P < 0.001) even when adjusted for age and sex. CONCLUSION: Overweight and obesity rates at this public hospital are alarming and may indicate a problem in public hospitals across the United States. The process and structure of care for overweight and obese patients need to be evaluated, and training for residents needs to address this problem.

Academic Medical Centers↗
PubMed2003

CCAAT/enhancer binding protein alpha interacts with ZTA and mediates ZTA-induced p21(CIP-1) accumulation and G(1) cell cycle arrest during the Epstein-Barr virus lytic cycle.

Cellular CCAAT/enhancer binding protein alpha (C/EBPalpha) promotes cellular differentiation and has antimitotic activities involving cell cycle arrest at G(1)/S through stabilization of p21(CIP-1)/WAF1 and through transcriptional activation of the p21 promoter. The Epstein-Barr virus lytic-cycle transactivator protein ZTA is known to arrest the host cell cycle at G(1)/S via a p53-independent p21 pathway, but the detailed molecular mechanisms involved have not been defined. To further evaluate the role of ZTA in cell cycle arrest, we constructed a recombinant adenovirus vector expressing ZTA (Ad-ZTA), whose level of expression at a low multiplicity of infection in normal human diploid fibroblast (HF) cells was lower than or equal to the physiological level seen in Akata cells lytically induced by EBV (EBV-Akata cells). Fluorescence-activated cell sorting analysis of HF cells infected with Ad-ZTA confirmed that G(1)/S cell cycle arrest occurred in the majority of ZTA-positive cells, but not with an adenovirus vector expressing green fluorescent protein. Double-label immunofluorescence assays (IFA) performed with Ad-ZTA-infected HF cells revealed that only ZTA-positive cells induced the expression of both endogenous C/EBPalpha and p21 and blocked the progression into S phase, as detected by a lack of incorporation of bromodeoxyuridine. The stimulation of endogenous ZTA protein expression either through treatment with tetradecanoyl phorbol acetate in D98/HR1 cells or through B-cell receptor cross-linking with anti-immunoglobulin G antibody in EBV-Akata cells also coincided with the induction of both C/EBPalpha and p21 and their mRNAs, as assayed by Northern blot, Western blot, and IFA experiments. Mechanistically, the ZTA protein proved to directly interact with C/EBPalpha by coimmunoprecipitation in EBV-Akata cells and with DNA-bound C/EBPalpha in electrophoretic mobility shift assay experiments, and the in vitro interaction domain encompassed the basic leucine zipper domain of ZTA. ZTA also specifically protected C/EBPalpha from degradation in a protein stability assay with a non-EBV-induced Akata cell proteasome extract. Furthermore, both C/EBPalpha and ZTA were found to specifically associate with the C/EBPalpha promoter in chromatin immunoprecipitation assays, but the interaction with ZTA appeared to be mediated by C/EBPalpha because it was abolished by clearing with anti-C/EBPalpha antibody. ZTA did not bind to or activate the C/EBPalpha promoter directly but cooperatively enhanced the positive autoregulation of the C/EBPalpha promoter by cotransfected C/EBPalpha in transient luciferase reporter gene assays with Vero and HeLa cells as well as with DG75 B lymphocytes. Similarly, ZTA alone had little effect on the p21 promoter in transient reporter gene assays, but in the presence of cotransfected C/EBPalpha, ZTA enhanced the level of C/EBPalpha activation. This effect proved to require a previously unrecognized region in the proximal p21 promoter that contains three high-affinity C/EBPalpha binding sites. Finally, in C/EBPalpha-deficient mouse embryonic fibroblasts (MEF), Ad-ZTA was unable to induce either p21 or G(1) arrest, whereas it was able to induce both in wild-type MEF. Overall, we conclude that C/EBPalpha is essential for at least one pathway of ZTA-induced G(1) arrest during EBV lytic-cycle DNA replication and that this process involves a physical piggyback interaction between ZTA and C/EBPalpha leading to greatly enhanced C/EBPalpha and p21 levels through both transcriptional and posttranslational mechanisms.

Adenoviridae↗
PubMed2003

The yeast RSC chromatin-remodeling complex is required for kinetochore function in chromosome segregation.

The accurate segregation of chromosomes requires the kinetochore, a complex protein machine that assembles onto centromeric DNA to mediate attachment of replicated sister chromatids to the mitotic spindle apparatus. This study reveals an important role for the yeast RSC ATP-dependent chromatin-remodeling complex at the kinetochore in chromosome transmission. Mutations in genes encoding two core subunits of RSC, the ATPase Sth1p and the Snf5p homolog Sfh1p, interact genetically with mutations in genes encoding kinetochore proteins and with a mutation in centromeric DNA. RSC also interacts genetically and physically with the histone and histone variant components of centromeric chromatin. Importantly, RSC is localized to centromeric and centromere-proximal chromosomal regions, and its association with these loci is dependent on Sth1p. Both sth1 and sfh1 mutants exhibit altered centromeric and centromere-proximal chromatin structure and increased missegregation of authentic chromosomes. Finally, RSC is not required for centromeric deposition of the histone H3 variant Cse4p, suggesting that RSC plays a role in reconfiguring centromeric and flanking nucleosomes following Cse4p recruitment for proper chromosome transmission.

Carrier Proteins↗
PubMed2003

Codon 249 mutation in exon 7 of p53 gene in plasma DNA: maybe a new early diagnostic marker of hepatocellular carcinoma in Qidong risk area, China.

AIM: One of the characteristics of hepatocellular carcinoma (HCC) in Qidong area is the selective mutation resulting in a serine substitution at codon 249 of the p53 gene (1, 20), and it has been identified as a "hotspot" mutation in heptocellular carcinomas occurring in populations exposed to aflatoxin and with high prevalence of hepatitis B virus carriers (2,3,9, 10,16,24). We evaluated in this paper whether this "hotspot" mutation could be detected in cell-free DNA circulating in plasma of patients with hepatocellular carcinoma and cirrhosis in Qidong, China, and tried to illustrate the significance of the detection of this molecular biomarker. METHODS: We collected blood samples from 25 hepatocellular carcinoma patients, 20 cirrhotic patients and 30 healthy controls in Qidong area. DNA was extracted and purified from 200 microl of plasma from each sample. The 249(Ser) p53 mutation was detected by restriction digestion analysis and direct sequencing of exon-7 PCR products. RESULTS: We found in exon 7 of p53 gene G-T transversion at the third base of codon 249 resulting 249(Arg) - 249(Ser) mutation in 10/25 (40 %) hepatocellular carcinoma cases, 4/20 (20 %) cirrhotics, and 2/30 (7 %) healthy controls. The adjusted odds ratio for having the mutation was 22.1(95 % CI, 3.2-91.7) for HCC cases compared to controls. CONCLUSION: These data show that the 249(Ser) p53 mutation in plasma is strongly associated with hepatocellular carcinoma in Qidong patients. We found this mutation was also detected, although it was at a much lower frequency, in plasma DNA of Qidong cirrhotics and healthy controls; We consider that these findings, together with the usual method of HCC diagnosis, will give more information in early diagnosis of HCC, and 249(Ser) p53 mutation should be developed to a new early diagnostic marker for HCC.

Adult↗
PubMed2003

Pathogenicity of GB virus C on virus hepatitis and hemodialysis patients.

AIM: To determine the pathogenicity of GB virus C (GBV-C) on liver and the effects of its co-infection on the clinical features and prognosis of patients with hepatitis B and C. METHODS: Cross-sectional study was carried out in 413 patients with acute, chronic hepatitis B or liver cirrhosis, and in 67 hemodialysis patients. A 20-month prospective cohort study was carried out in 95 hepatitis B and 80 hepatitis C patients. A reverse transcriptase nested polymerase chain reaction (RT-nPCR) of the 5'-noncoding region was used to detect circulating GBV-C RNA. Liver function was determined by an automated analyzer for all patients. RESULTS: The prevalence of GBV-C in the high-risk populations with the virus transmitted via blood was high, ranging from 16.2 to 28.8 %. Co-infection with GBV-C in hepatitis B patients did not affect the clinical features of the disease or liver function. The dialysis patients infected with GBV-C alone did not develop functional changes to the liver. Prospective cohort study showed that GBV-C co-infection did not affect the clinical features, prognosis or negative serum conversion rate of chronic hepatitis B and C. CONCLUSION: The results suggest that GBV-C has no marked pathogenicity on liver, so it may not be a hepatitis virus.

Cohort Studies↗
PubMed2003

[Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) expression in superficial transitional cell bladder carcinoma].

BACKGROUND & OBJECTIVE: Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) can promote the proliferation of endothelial cell and angiogenesis. They are important materials in growth, invasion, and metastasis of tumor. There were few reports of their difference in single and multiple superficial transitional cell bladder carcinoma. Our objective was to study the expression of them in single and multiple superficial transitional cell bladder carcinoma and their clinical significance. METHODS: Immunohistochemical method was used to study the VEGF and bFGF expression in 60 cases of superficial transitional cell bladder carcinoma and in 10 cases of normal bladder tissue (as control). RESULTS: The expression levels of VEGF (55.6%), bFGF (50.0%), and coexpression level of VEGF and bFGF (50.0%) in the multiple superficial transitional cell bladder carcinoma were higher than that in single tumor. The recurrent rate in the patients with VEGF high expression (61.1%) was higher than that in the patients with VEGF low expression (16.7%). CONCLUSION: The expression levels of VEGF and bFGF were correlated with the biological behavior of superficial transitional cell bladder carcinoma.

Carcinoma, Transitional Cell↗
PubMed2003

[Mutational studies of adenomatous polyposis coli gene in carcinomas from patients with hereditary non-polyposis colorectal cancers].

OBJECTIVE: To analyze the mutational features of adenomatous polyposis coli (APC) gene and to explore the effect of mismatch repair (MMR) deficiency on its mutations in hereditary non-polyposis colorectal cancers (HNPCC). METHODS: PCR-based in vitro synthesized protein test (IVSP) assay and sequencing analysis were used to confirm somatic mutations of whole APC gene in 19 HNPCC patients. RESULTS: Eleven cases with thirteen mutations were determined. The frequency of APC mutation was 58%(11/19). The exhibiting mutations consisted of 9 frameshift mutations and 4 nonsense ones, indicating the existence of more frameshift mutations (69%). All of frameshift mutations were deletion or insertion of 1-2 bp and most of them (7/9) happened at simple nucleotide repeat sequences, particularly within (A) n tracts (5/9). All of four nonsense mutations resulted from C to T transitions at CpG sites. CONCLUSION: Mutational inactivations of APC gene were detected in more than half of HNPCC patients in this study, indicating that APC mutation is a common molecular event in the tumorigenesis of HNPCC. According to the location of frameshift mutations at simple nucleotide repeat sequences and point mutations at CpG sites, it was suggested that endogenous mechanisms like MMR deficiency might exert an effect on the nature of APC mutations in most HNPCC.

Adenomatous Polyposis Coli↗
PubMed2003

[Investigations on the molecular mechanisms of saponins from Anemarrhena asphodeloides Bunge using oligonucleotide microarrays].

AIM: To investigate the molecular mechanisms of saponins from the rhizome of Anemarrhena asphodeloides Bunge. METHODS: Oligonucleotide microarrays consisting of 87 probes representing 87 human cardiovascular disease-related genes were constructed. Effects of saponins on gene expression in human umbilical vein endothelial cells were analyzed by comparing hybridization of Cy 5-labeled cDNAs from saponins-treated human umbilical vein endothelial cells and Cy 3-labeled cDNAs from untreated human umbilical vein endothelial cells. RESULTS: The results indicate that angiotensinogen gene, alpha 2A-adrenoceptor gene and endothelin-converting enzyme 1 gene were downregulated 2.8, 1.9 and 3.1 folds respectively after human umbilical vein endothelial cells were incubated in medium containing 80 mg.L-1 saponins. CONCLUSION: These results suggest that saponins may have beneficial effect on cardiovascular diseases by modulating the function of vein endothial cells and microarray can be used to investigate the biological action of extracts from traditional Chinese medicine.

Anemarrhena↗
PubMed2003

[Expression of extracellular matrix metalloproteinase inducer in human bladder transitional cell carcinoma].

BACKGROUND & OBJECTIVE: Matrix metalloproteinases(MMPs) play critical roles in the process of tumorigenesis, tumor invasion and metastasis. Extracellular matrix metalloproteinase inducer (EMMPRIN) derived from cancer cell can induce stromal fibroblasts to synthesize MMPs, which advances the invasion and metastasis of cancer. This study was designed to investigate the roles of EMMPRIN in the tumorigenesis, invasion and metastasis of bladder carcinoma by detecting the expression of EMMPRIN in human normal and carcinomatous bladder tissues. METHODS: The expression of EMMPRIN was examined in 45 bladder carcinoma tissues from 45 patients and normal bladder mucosa from 9 persons by immunohistochemistry SP method. The relationship between EMMPRIN expression and clinicopathologic parameters was analyzed. RESULTS: EMMPRIN protein was localized at membrane and cytoplasm of carcinomatous epithelial cell, but was not expressed in normal bladder epithelial or tumor stromal cell. The overall positive rate of EMMPRIN in 45 cases of bladder carcinoma was 73%. The positive rates of EMMPRIN in grade II, grade III and recurrent carcinomas were 84%, 85%, and 100%, respectively, significantly higher than those in grade I and non-recurrent carcinomas (14% and 56%, respectively) (P< 0.05). The intensive positive rate of EMMPRIN in lymph node metastasis group (86%) was significantly higher than that in no lymph node metastasis group (24%) (P< 0.05). CONCLUSION: EMMPRIN was overexpressed in human bladder transitional cell carcinoma, and related to the malignant degree and recurrence. It could be a useful indicator for the assessment of potent invasion and metastasis of bladder carcinoma.

Adult↗
PubMed2003

[Treatment of open fracture by vacuum sealing technique and internal fixation].

OBJECTIVE: To investigate the effect of vacuum sealing(VS) technique and emergency internal fixation on the management of limbs open fracture and soft tissue dirty defects. METHODS: Fourteen patients (18 limbs) with open fracture and soft tissue dirty defects were treated by the VS technique and internal fixation after debridement and 14 patients managed by traditional method as control group. Wound surface were covered with polyvinyl alcohol foams with embedded drainage tubes connected with vacuum bottle (negative pressure of 50 to 60 kPa) after wound surface were debrided and fracture were fixed. Wound closure was performed with secondary suturing, or free flap, or loco-regional flap and mesh-grafts after 5 to 7 days. RESULTS: All wound surface healed completely. No complications (systemic and local) were found. After 4-6 months follow-up on average, the fracture healed well. There was significant difference in time of treatment, total cost of treatment and complication rate between 2 groups (P < 0.01). CONCLUSION: The VS procedure can drain the wound surface completely, decrease infection rate and stimulate the proliferation of granulation tissue. A combination of VS with emergency internal fixation is a simple and effective method in treatment of limbs open fracture and soft tissue dirty defects.

Adolescent↗
PubMed2003

Orthotopic ileal neobladder similar to original bladder.

OBJECTIVE: To report the surgical techniques and results of an 8-year follow-up study of 42 patients with a modified orthotopic ileal neobladder restoring normal anatomical relationship. METHODS: Total cystoprostatectomy was performed extraperitoneally. A 45 - 50 cm segment of the ileal loop was isolated, detubularized, and reconfigured into an "M"-shape to form a pouch. Bilateral ureters were implanted by inserting 1 cm distal segment into the pouch. The bottom of pouch was opened and anastomosed with the urethra. RESULTS: Forty-two patients were followed up for 6 to 96 months,90.5% of whom were continent in the daytime, and 85.7% at night. Two patients had a difficulty in urination. The average volume of the pouch was (361 +/- 48) ml at 12 months postoperation. Urodynamic examination showed the average peak voiding pressure was (86.8 +/- 21.4) cm H(2)O. The average maximum flow rate (Qmax) was (18.4 +/- 6.1) ml/s. No remarkable ureter reflux and obstruction were found. No patient was detected to have urethral carcinoma. CONCLUSIONS: Extraperitoneal cystectomy can avoid the tumor contamination of the abdomen and intestinal interference of the operative field. The ureter-inserting implantation technique is a simple anti-reflux anastomosis method with less ureter stenosis rate. Isolating the neobladder and ureters from the peritoneal cavity can reduce the postoperative complications, such as adhesive ileus, internal hernia, and urine leakage into the peritoneal cavity. The neobladder is similar to the original bladder in position, volume, shape and anti-reflux ureter connection.

Adult↗
PubMed2003

[Dynamic observation of cytokine induced killer cells in peripheral blood from patients with chronic hepatitis B].

AIM: To observe dynamically proliferation and cytotoxicity of cytokine induced killer cells (CIKs) in peripheral blood from patients with persistent infection of hepatitis B virus. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated routinely from 10 normal volunteers (control group) and 20 patients with chronic hepatitis B. PBMCs were co-cultured with IFN-gamma, rhIL-2 and anti-CD3 mAb to induce CIK cell generation. The expressions of single staining CD3, CD4, and CD8, as well as double staining CD4 CD25, CD3 CD56 and CD28 CD95 on CIK cells were analyzed by flow cytomctry on 3,6,12,24 and 30 days of co-culture. RESULTS: The proliferative level and killer activity of CIK cells from the patients were lower than those from control group. The proliferative level, killer activity and expressions of above surface markers on CIK cells from the patients at various times after co-culture were higher than those before co-culture, and reached peak values on 12 days after co-culture. CONCLUSION: The proliferative level and killer activity of CIK cells from the patients are lower than that of normal people, which may be the reason of persistent development of HBV infection.

Cytokines↗
PubMed2003

[Meconium-stained amniotic fluid and intra-amniotic infection].

OBJECTIVE: To explore the relationship between meconium-stained amniotic fluid and Fifty-six women of cesarean section with intact membrane and intra-amniotic infection. METHODS: without parturient were divided into 3 groups according to the property of amniotic fluid (no meconium, I to approximately II degree meconium stainedness, and III degree mecomium stainedness). The content of interleukin-6 in amniotic fluid was measured with ELISA. The infiltration of inflammatory cells in the placenta and its membrane was determined by the pathological diagnosis. The neonatal Apgar score and puerperial infection after the surgery were analyzed. RESULTS: There were no significant differences in the content of IL-6 in amniotic fluid and in the infiltration of inflammatory cells among the 3 groups. But the rate of neonatal asphyxia in the meconium-stained cases was significantly higher than that without meconium. CONCLUSION: Meconium-stained amniotic fluid is a marker of fetal distress, but it is not related to intra-amniotic infection.

Adult↗
PubMed2002

[Clinical analysis of 242 cases of controlled preterm delivery].

OBJECTIVE: To understand the effect of controlled premature delivery and its termination method of pregnancy. METHODS: The clinical data of 242 cases of controlled premature delivery were retrospectively analyzed. RESULTS: The incidence of premature delivery was 5.75% and the incidence of controlled premature delivery was 46.81%. Pregnancy induced hypertension (PIH) was the first-place reason of controlled premature delivery. The cesarean section rate of controlled premature delivery was 64.88%, which was significantly higher than that of natural premature delivery (16.45%, P < 0.05); the rate of postpartum hemorrhage and neonatal suffocation in controlled premature delivery was significantly lower than that of natural premature delivery (P < 0.05). CONCLUSION: Appropriately controlled premature delivery can be beneficial to the newborn's survival rate and can lower the mortality of pregnant women.

Adult↗
PubMed2002

Regional differences in ventricular fibrillation in the open-chest porcine left ventricle.

It has been hypothesized that during ventricular fibrillation (VF), the fastest activating region, the dominant domain, contains a stable reentrant circuit called a mother rotor. This hypothesis postulates that the mother rotor spawns wavefronts that propagate to maintain VF elsewhere and implies that the ratio of wavefronts propagating off a region to those propagating onto it (propoff/propon) should be >1 for the dominant domain but <1 elsewhere. To test this prediction in the left ventricular (LV) epicardium of a large animal, most of the LV free wall was mapped with 1008 electrodes in 7 pigs. VF activation rate was faster in the posterior than in the anterior LV (10.0+/-1.3Hz versus 9.3+/-1.3Hz; P<0.001). The anterior LV had a higher fraction of wavefronts that blocked than did the posterior LV and had a propoff/propon ratio <1 (P<0.001). The mean conduction velocity vectors of the VF wavefronts pointed in the direction from the posterior to the anterior LV. Although these findings favor a dominant domain in the posterior LV, the facts that the anterior LV had a higher incidence of reentry than did the posterior LV and that the posterior LV did not have propoff/propon significantly different from 1 do not. Thus, quantitative regional differences are present over the porcine LV epicardium during VF. Although these differences are not totally consistent with the presence of a dominant domain within the LV free wall, the mean conduction velocity vector is consistent with one in the septum.

Animals↗