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Yong Zeng

Publications and source records attributed to Yong Zeng.

At least 19 recordsLinked to original sources
PubMed2026

Detection and classification of lymphoma from cell-free methylome data.

Diagnosing lymphoma traditionally relies on invasive tissue biopsies, which can yield insufficient material for histopathological evaluation and carry a risk of complications. Minimally invasive assessment of cell-free DNA (cfDNA) in plasma offers a promising alternative for lymphoma detection that could aid the rapid evaluation of malignant vs. benign lymphadenopathy. Here, we examine the methylome of plasma samples from 165 lymphoma patients and 47 controls using cell-free methylated DNA immunoprecipitation and high-throughput sequencing (cfMeDIP-seq). Differential methylation analysis of a discovery cohort (142 out of 212 samples) revealed 13,897 hypermethylated genomic regions in lymphoma cases, which were subsequently used for classification using regularized binomial generalized linear models. In a validation cohort (70 samples), we identified lymphomas with an accuracy of 0.89, positive predictive value (PPV) of 0.90 and negative predictive value (NPV) of 0.87. cfDNA methylation scores were significantly associated with orthogonal measures of cfDNA tumor burden, stage, and clinical outcomes. Our results highlight the feasibility of cfDNA methylation profiling as a sensitive and minimally invasive method for detecting lymphoma.

Journal Article↗
PubMed2006

Tryptophan hydroxylase-2 gene variation influences personality traits and disorders related to emotional dysregulation.

Variation in the tryptophan hydroxylase-2 gene (TPH2) coding for the rate-limiting enzyme of serotonin (5-HT) synthesis in the brain modulates responses of limbic circuits to emotional stimuli and has been linked to a spectrum of clinical populations characterized by emotional dysregulation. Here, we tested a set of common single nucleotide polymorphisms (SNPs) in and downstream of the transcriptional control region of TPH2 for association with personality traits and with risk for personality disorders in two cohorts comprising of 336 healthy individuals and 420 patients with personality disorders. Personality dimensions were assessed by the Tridimensional Personality Questionnaire (TPQ) and the revised NEO Personality Inventory (NEO-PI-R). Personality disorders were diagnosed with the Structured Clinical Interview of DSM-IV and were allocated to clusters A, B, and C. Individual SNP and haplotype analyses revealed significant differences in genotype frequencies between controls and cluster B as well as cluster C patients, respectively. In both patient groups, we observed overrepresentation of T allele carriers of a functional polymorphism in the upstream regulatory region of TPH2 (SNP G-703T, rs4570625) which was previously shown to bias responsiveness of the amygdala, a structure critically involved in emotionality. Furthermore, significant effects of TPH2 variants on anxiety-related traits defined primarily by the TPQ Harm Avoidance were found in healthy individuals. The results link potentially functional TPH2 variants to personality traits related to emotional instability as well as to cluster B and cluster C personality disorders. These findings implicate alterations of 5-HT synthesis in emotion regulation and confirm TPH2 as a susceptibility and/or modifier gene of affective spectrum disorders.

Adolescent↗
PubMed2006

Identification and characterization of two mature isoforms of retinoschisin in murine retina.

Retinoschisin (RS) is a 24 kDa secreted protein expressed in retina and is required for the structural and functional integrity of the retina. RS has been predicted to serve as an adhesive protein but the precise molecular mechanism by which it functions in retina is not yet known. During investigations on structural and functional aspects of RS in murine retina using proteomic tools, we identified two isoforms of RS that differed in mass by 200 Da with no apparent change in charge. Mass spectra and amino acid sequence analysis of the tryptic peptides revealed that these isoforms differed by two amino acids at the N-terminus which suggested processing of RS signal sequence at two cleavage sites by signal peptidase as the basic mechanism underlying the occurrence of two mature RS isoforms in retina. Bioinformatic analysis identified two potential cleavage sites (between amino acids 21-22 and 23-24) in RS signal sequence. The flexibility of the signal peptidase to cleave at two sites is correlated to the amino acid composition of the RS signal sequence. This finding represents a rare example of a naturally occurring signal sequence cleavage at more than one site in vivo.

Amino Acid Sequence↗
PubMed2006

Optical properties of two-dimensional negative-phase-velocity-medium photonic crystals.

By an extended plane-wave-based transfer-matrix method, the photonic band structure and the corresponding transmission spectrum have been calculated for a two-dimensional photonic crystal composed of negative-phase-velocity-medium (NPVM) cylindrical rods. Dispersionless anticrossing bands in the two-dimensional NPVM periodic structure are generated by the couplings among surface polaritons localized in the NPVM rods. In part of the negative-phase-velocity frequency region, the photonic band structures of the NPVM photonic crystal are characterized by a topographical continuous dispersion relationship accompanied by many anticrossing bands. The effect of the filling fraction of the NPVM rods on the optical properties of photonic crystals has also been studied.

Journal Article↗
PubMed2006

[Introduction of microvascular surgery to biliary reconstruction in living donor liver transplantation].

OBJECTIVE: To explore the feasibility of introduction of microvascular surgery into biliary reconstruction in living donor liver transplantation (LDLT) so as to reduce the incidence of postoperative biliary complications. METHODS: The experience in the microvascular surgery performed on 32 patients undergoing LDLT, 8 children and 24 adults, including duct-to-duct anastomosis in 21 case, hepato-jejunostomy under surgical loupe in 13 cases, and hepato-jejunostomy under operative microscopy in 9 cases, totally 43 cases of biliary reconstruction manipulations. RESULTS: Post-operative biliary complications occurred in 2 patients. One male patient who underwent hepato-jejunostomy under surgical loupe suffered from leakage from a bilioenteric anastomotic stoma 3 days after operation and laparotomy was performed to repair the leakage and carry out drainage. Mild stricture of the anastomotic stoma occurred in the other patient 3 months after operation and conservative treatment was given. Both patients recovered. CONCLUSION: Introduction of microvascular surgery to biliary reconstruction in LDLT, especially the use of operative microscopy for hepato-jejunostomy on very small hepatic ducts, <or= 2 mm in diameter, achieves good results, with significant reduction of post-operative complications.

Adolescent↗
PubMed2006

[Modifications of surgical technique in adult-to-adult living donor liver transplantation].

OBJECTIVE: To report the authors' experience with adult-to-adult living donor liver transplantation using right lobe liver grafts performed by a modified technique. METHODS: From March to June 2005, 13 patients underwent living donor liver transplantation using right lobe grafts. Among these, one patient received two left lobes from his two elder sisters, one received a right lobe from his mother and a left lobe from a cadaveric donor. All patient underwent a modification designed to improve the reconstruction of right hepatic vein, the reconstruction the tributaries of the middle hepatic vein by interpositioning a vein grafts, and the anastomosis of the hepatic arteries and bile ducts. RESULTS: There were no severe complications and deaths found in donors. Four complications occurred in recipients including hepatic artery thrombosis (n = 1), bile leakage (n = 1), left subphrenic abscess (n = 1) and pulmonary infection (n = 1). The patient with pulmonary infection died of multiple organ failure (MOF). All patients underwent direct anastomosis of right hepatic vein and inferior vena cava (IVC), 5 cases plus the reconstructions of right inferior hepatic vein, and the other 5 cases plus the reconstruction of the tributaries of the middle hepatic vein by interpositioning a vein graft to provide sufficient venous outflow. The graft and recipient weight ratio (GRWR) were between 0.72% and 1.24%, among these, 9 cases < 1.0% and 2 cases < 0.8%, and there was no "small-for-size syndrome" occurred. CONCLUSIONS: With modifications of surgical technique, especially the reconstruction of hepatic vein to provide sufficient venous outflow, living donor liver transplantation in adults using right lobe liver grafts can become a relatively safe procedure and prevent the "small-for-size syndrome".

Adult↗
PubMed2006

[Adult-to-adult living donor liver transplantation using right lobe graft: report of 24 cases].

OBJECTIVE: To investigate the safety and feasibility of adult-to-adult living donor liver transplantation (A-A LDLT) using right lobe graft. METHODS: From January 2005 to December 2005, 24 patients, 22 males and 2 females, aged 20 - 53, with the underlying diseases of liver cirrhosis, hepatocellular carcinoma, and Budd-Chiari syndrome, underwent A-A LDLT using right lobe graft. During the second period, including 22 cases, modified techniques were adopted, e.g. direct anastomosis of the right hepatic vein (RHV) and inferior vena cava was performed in all 22 cases, reconstruction of inferior right hepatic vein was performed on 9 cases, and reconstruction of tributaries of middle hepatic vein by interposing a vein graft on 10 cases so as to provide sufficient venous outflow. RESULTS: No sever complication and death was found in the donors. The graft and recipient weight ratio was 0.72% - 1.17%, being < 1.0% among 19 cases and being < 0.8% among 4 cases. During the first period one of the 2 patients suffered from stenosis at the anastomotic stoma of the right hepatic vein, and the other patient suffered from small-for-size syndrome and died. During the second period modified techniques were adopted and no more small-for-size syndrome occurred. CONCLUSION: With the modified techniques, A-A LDLT has become a relative safe procedure.

Adult↗
PubMed2006

[Safety of donor of right lobe graft in living donor liver transplantation].

OBJECTIVE: To evaluate the safety of donors of right lobe graft. METHODS: We retrospectively studied 13 living donors of right lobe graft from January 2002 to June 2005. The right lobe grafts were obtained by transecting the liver on the right side of the middle hepatic vein. Liver transection was done by using an ultrasonic dissector without inflow vascular occlusion. The standard liver volume and the ratio of left lobe volume to the standard liver volume were calculated. RESULTS: The mean blood loss was 490 ml. The mean blood transfusion was 440 ml. In the perioperative period the mean albumin administered was 85 g. One donor had portal vein trifurcation, two had a right posterior bile duct and a right anterior bile duct draining into the left bile duct, respectively. One had bile ducts from left lateral and left internal segment and right duct draining into common hepatic duct. On postoperative day 1 the donors' liver functions were found impaired to some extent, but all the indices rapidly returned to the normal level at the end of the first week. Postoperative complications included 1 case of abdominal bleeding, 2 wound steatosis and 1 chyle leak. There was no donor mortality. All donors are well and have returned to their previous occupations. CONCLUSIONS: The donation of right lobe graft for adult living donor liver transplantation is safe provided that the patency of the remnant hepatic vasculature and bile duct is ensured, the volume of the remnant liver exceeds 30% of the total liver volume, and there is no injury to the remnant liver.

Adult↗
PubMed2006

Confinement effects on electromigration of long DNA molecules in an ordered cavity array.

Confinement effects on the electromigration of long dsDNA molecules in an array of well-ordered, molecular sized cavities interconnected by nanopores are described. The array was prepared by replicating the structure of a colloidal crystal of microspheres in a polymer matrix. Both conformation and mobility studies show that the electrophoretic behavior of large DNA molecules is distinct from that in gels and other microfabricated sieves, showing a peak in mobility versus electric field, and an inversion in the separation order with field strength. A simple model was proposed to interpret this unexpected observation qualitatively. We conclude that the molecular behavior of DNA can be modified by the combination of entropic effect and electric trapping as a consequence of both unique geometry and conductivity of this cavity array material. This approach provides insights for design and optimization of on-chip molecular sieving structures for rapid separation of long DNA molecules. It may lead to a promising material for manipulation and size fractionation of other biological macromolecules.

DNA↗
PubMed2006

Activation of signaling pathways and stress-response genes in an experimental model of retinal detachment.

PURPOSE: Despite the high metabolic demands of the neural retina, its detachment from the retinal pigment epithelium does not lead to immediate death for most of the cells. This study was undertaken to test the hypothesis that intrinsic protective mechanisms are activated in the neural retina during early stages of retinal detachment. METHODS: Retinal detachments were created in Brown Norway rats by injection of 1% hyaluronic acid into the subretinal space. Gene expression profiles of retinas detached for 24 hours were generated with a gene microarray (rat U34 GeneChips; Affymetrix, Santa Clara, CA) and compared to the profiles from control attached retinas in a robust multiarray protocol and false-discovery-rate analysis. Changes in individual, differentially expressed genes were validated by quantitative real-time polymerase chain reaction (qRT-PCR) analysis. Additional qRT-PCR and immunoblot analyses were performed for additional selected genes. RESULTS: Genome-wide expression profiling revealed 27 genes that are differentially expressed in retinas detached for 24 hours. In silico analysis and functional clustering suggested that most genes belonged to three signaling pathways: interleukin-6/STAT, transforming growth factor-beta/Smad, and aryl hydrocarbon receptor oxidative stress response. Additional analyses of selected genes from these pathways demonstrated a time-dependent increase in their expression in detached retinas. CONCLUSIONS: Retinal detachment results in the early activation of stress-response genes and specific signaling pathways. This adaptive response may enable the photoreceptor cells to survive the acute phase of a retinal detachment, and it is the breakdown of these protective mechanisms in chronic disease that leads to the ultimate death of the cell.

Animals↗
PubMed2006

[Adult-to-adult living donor liver transplantation].

OBJECTIVE: To investigate the approach which could improve the survival rate of adult-to adult living donor liver transplantations, that right lobe liver grafts were performed by a modified technique. METHODS: During from March to June 2005, 13 patients underwent the living donor liver transplantation with right lobe grafts via the improved surgical techniques including the reconstruction of right hepatic vein; the tributaries of the middle hepatic vein were reconstructed by interpositioning a vein grafts; the anastomosis of the hepatic arteries and bile ducts. All cases underwent the direct anastomosis of right hepatic vein and IVC, of whom 5 cases were added with the reconstructions of right inferior hepatic vein, and other 5 cases added with reconstructing the tributaries of the middle hepatic vein by interpositing a vein graft to provide sufficient venous outflow. RESULTS: No donor suffered from severe complication or death. Four complications occurred in recipients who got the hepatic artery thrombosis (1 case), bile leakage (1 case), right subphrenic abscess (1 case) or pulmonary infection (1 case) respectively. The recipient with pulmonary infection died of MOF. The graft organ and recipient weight ratio (GRWR) were between 0.72% and 1.24%, that the ratios of 9 cases was < 1.0% and 2 cases < 0.8%, with no "small-for-size syndrome" occurred. CONCLUSIONS: The improved surgical techniques, especially the reconstruction of hepatic vein to provide sufficient venous outflow, can make the adult-to-adult living donor liver transplantation with right lobe liver grafts become a relatively safe operation and prevent the "small-for-size syndrome".

Adult↗
PubMed2006

[Early ST resolution after successful primary PCI is related to a favorable outcome in ST elevated AMI patients].

OBJECTIVE: To analyze the relationship between the early ST resolution magnitude and TIMI flow, MACE and the cardiac function in ST elevated AMI (STEMI) patients after successful primary PCI. METHODS: A total of 120 consecutive patients with STEMI underwent primary PCI within 12 hours after the onset of chest pain were enrolled in this study, the ST segment resolution was calculated and the patients were divided into group A (n = 81, Sigma STE resolved > or = 50%) and group B (n = 39, Sigma STE resolved < 50%). TIMI flow after PCI, clinical events up to 30 days post PCI and cardiac function 30 days post PCI were assessed. RESULTS: LVEF was higher in group A than that of group B (58.6% +/- 7.1% vs. 50.5% +/- 7.1%, P < 0.05). There are fewer patients with Killip III and IV in group A than in group B (1.2% vs. 12.8%, P < 0.05). The incidence of in-hospital MACE was also significantly less in group A than in group B (0 vs. 7.7%, P < 0.001). As expected, there were more patients with TIMI 3 flow (95.1% vs. 79.5%, P < 0.05) and fewer TIMI 2 (4.9% vs. 20.5%, P < 0.05) flow post PCI in group A than in group B and all 3 patients with MACE were group B patients with TIMI 2 flow. CONCLUSION: Early ST resolution post PCI represents improved myocardial perfusion and function and is related to a favorable clinical outcome in STEMI patients.

Aged↗
PubMed2006

[Clinical application of uvulopalatopharyngoplasty with uvula preservation and tongue base radiofrequency reduction].

OBJECTIVE: To explore the effect of uvulopalatopharyngoplasty with uvula preservation and radiofrequency tongue base reduction for obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Forty six patients with OSAHS were enrolled. One group (n = 22) of patients only received uvulopalatopharyngoplasty with uvula preservation, while the other group (n = 24) had both uvulopalatopharyngoplasty with uvula preservation and radiofrequency tongue base reduction. Polysomnography and distance between anterior pillars (DBAP), distance between posterior pillars (DBPP), length of roft palate, distance between tongue base and posterior pharyngeal wall (DBTP) were measured before and 6 months after surgery. RESULTS: The pre-operation apnea hypopnea index (AHI), x +/- s, lowest SaO2 (LSaO2) of first group were (56. 5 +/- 6. 0)/h, and 0.626 +/- 0.060 respectively, and 6 months after surgery, AHI was (23.7 +/- 2.7)/h, LSaO2 was 0.797 +/- 0.053. The pre-operation AHI, LSaO2 of second group were (58.4 +/- 5.1)/h, and 0.650 +/- 0.057 respectively, and 6 months after surgery, AHI was (15.5 +/- 3.2)/h, LSaO2 was 0.864 +/- 0.064. After surgery AHI and LSaO2 have changed in both groups (P<0.001). Six months after operation, DBAP and DBPP became withy, length of soft palate became short (P<0. 001). In one group the validity ratio is 72.7% (16/22), the other group the validity ratio is 87.5% (21/24) (P< 0.05), and pharyngeal posterior airway width (PPAW) became withy (P <0.001). CONCLUSIONS: For OSAHS patients, the obstructive regions should be evaluated. The combined surgery of uvulopalatopharyngoplasty with uvula preservation and radiofrequency tongue base reduction could have a better result.

Adult↗
PubMed2006

Modified techniques for adult-to-adult living donor liver transplantation.

BACKGROUND: Because of critical organ shortage, transplant professionals have utilized living donor liver transplantation (LDLT) in recent years. We summarized our experience in adult-to- adult LDLT with grafts of right liver lobe by a modified technique. METHODS: From January 2002 to August 2005, 24 adult patients underwent living donor liver transplantation with grafts of the right liver lobe at West China Hospital, Sichuan University, China. Twenty-two patients underwent modified procedures designed to improve the reconstruction of the right hepatic vein and the tributaries of the middle hepatic vein by interposing a great saphenous vein (GSV) graft and the anastomosis of the hepatic arteries and bile ducts. RESULTS: No severe complications and death occurred in all donors. In the first 2 patients, (patients 1 and 2), operative procedure was not modified. One patient suffered from "small-for-size syndrome" and the other died of sepsis with progressive deterioration of graft function. In the rest 22 patients (patients 3 to 24), however, the procedure of venous reconstruction was modified, and better results were obtained. Complications occurred in 7 recipients including acute rejection (2 patients), hepatic artery thrombosis (1), bile leakage (1), intestinal bleeding (1), left subphrenic abscess (1), and pulmonary infection (1). One patient with pulmonary infection died of multiple organ failure (MOF). The 22 patients underwent direct anastomosis of the right hepatic vein to the inferior vena cava (IVC), 9 direct anastomosis plus the reconstruction of the right inferior hepatic vein, and 10 direct anastomosis plus the reconstruction of the tributaries of the middle hepatic vein by interposing a GSV graft to provide sufficient venous outflow. Trifurcation of the portal vein was met in 3 patients. Venoplasty or separate anastomosis was performed. The ratio of graft to recipient body weight ranged from 0.72% to 1.17%. Among these patients, 19 had the ratio <1.0% and 4 <0.8%, and the ratio of graft weight to recipient standard liver volume was between 31.86% and 62.48%. Among these patients, 10 had the ratio <50% and 2 <40%. No "small-for-size syndrome" occurred in the 22 recipients who were subjected to modified procedures. CONCLUSIONS: With the modified surgical techniques for the reconstruction of the hepatic vein to obtain an adequate outflow and provide a sufficient functioning liver mass, living donor liver graft in adults using the right lobe can be safe to prevent the "small-for-size syndrome".

Adult↗
PubMed2006

[Perioperative management of severe obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To investigate the perioperative management of severe obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Fifty-three patients with severe OSAHS received uvulopalatopharyngoplasty with uvula preservation and radiofrequency tongue base reduction. All the patients were treated with automated continuous positive airway pressure (CPAP) for 3-7 days before operation and automated antibiotic therapy administered in the oropharynx, with 24 h ECG monitoring postoperatively. Polysomnography were carried out before and 6 months after surgery. RESULTS: The preoperative apnea hypopnea index (AHI) and lowest SaO(2) (LSaO(2)) were 58.4-/+5.1/h and 0.650-/+0.059, respectively, which were 15.5-/+3.2/h and 0.864-/+0.064 at 6 months after surgery, respectively, showing significant changes after surgery (P<0.01). Dyspnea occurred in 2 cases after operation, intraoperative bleeding in 1 case, primary bleeding in 2 cases and hypertension crisis in 1 case. CONCLUSION: Severe OSAHS patients are subject to great surgical risk. Application of auto-CPAP before operation can significantly improve the patients' tolerance of surgery and anesthesia, and reduce the surgical risks and preoperative complications.

Adult↗