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Yi Hu

Publications and source records attributed to Yi Hu.

50 records · Page 3Linked to original sources
PubMed2004

[Chemoradiotherapy followed by surgery in treatment of locally advanced esophageal carcinoma: a phase II trial].

BACKGROUND & OBJECTIVE: Recently, neoadjuvant therapy has become the focus of interest in an effort to prolong survival and reduce recurrence rates in patients with oesophageal cancer. This study was designed to evaluate the tolerance and the short-term outcome of chemoradiotherapy followed by surgery for patients with locally advanced esophageal squamous carcinoma, to observe effects of chemoradiotherapy on tumor resection rate, incidence of complications after surgery, and perioperative mortality. METHODS: From January 2000 to September 2003, Thirty-four consecutive patients with locally advanced esophageal squamous carcinoma were entered into this phase II study. The clinical pre-treatment staging of the tumors were determined by chest CT scan, abdomial CT Scan, EUS, and bronchoscopy examination. Chemotherapy and radiotherapy were performed concurrently. The chemotherapy consisted of Vinorelbine (or 5-Fluorouracil) and Cisplatin. 5-Fluorouracil at 2.4 g/m(2) was administered in continuous infusion for days 1-3 and days 22-25. Vinorelbine at 25 mg/m(2) per day was administered in bolus infusion on d1, d8, d22 and d29. Cisplatin at 75 mg/m(2) was administered by intravenously infusion on d1 and d22. A total radiotherapy dose of 40 Gy was delivered in 20 daily fractions of 2.0 Gy each (given 5 d/wk for 4 weeks). After completion of chemoradiotherapy, clinical restaging was performed. Esophagectomy and lymphadenectomies were performed 3-5 weeks after chemoradiotherapy. RESULTS: Thirty-three patients completed the planned chemoradiotherapy, and 32 patients underwent surgery. The toxicities of chemoradiotherapy such as myelotoxicity, pulmonary toxicity, esophagitis were grade I or II. No death was resulted from chemoradiotherapy. The clinical response rate of chemoradiotherapy was 85.3%, the pathological complete response rate was 25%, the resectability rate was 100%. Postoperative pulmonary infection occurred in 8 patients (22.9%), anastomotic leak in 3 patients (9.4%). Two patients (6.3%) died perioperatively because of ARDS and anastomotic leak complicated with heart failure. CONCLUSIONS: The short-term results of this study suggest that the strategy of chemoradiotherapy followed by surgery is safe,although it caused considerable toxicity and increased operation-related complications rate and perioperative mortality rate compared with surgery alone at the same period. Preoperative chemoradiotherapy is able to significantly reduce the tumor stage, and achieve substantially high clinical response rate and pathological complete response rate.

Adult↗
PubMed2003

Wnk1 kinase deficiency lowers blood pressure in mice: a gene-trap screen to identify potential targets for therapeutic intervention.

The availability of both the mouse and human genome sequences allows for the systematic discovery of human gene function through the use of the mouse as a model system. To accelerate the genetic determination of gene function, we have developed a sequence-tagged gene-trap library of >270,000 mouse embryonic stem cell clones representing mutations in approximately 60% of mammalian genes. Through the generation and phenotypic analysis of knockout mice from this resource, we are undertaking a functional screen to identify genes regulating physiological parameters such as blood pressure. As part of this screen, mice deficient for the Wnk1 kinase gene were generated and analyzed. Genetic studies in humans have shown that large intronic deletions in WNK1 lead to its overexpression and are responsible for pseudohypoaldosteronism type II, an autosomal dominant disorder characterized by hypertension, increased renal salt reabsorption, and impaired K+ and H+ excretion. Consistent with the human genetic studies, Wnk1 heterozygous mice displayed a significant decrease in blood pressure. Mice homozygous for the Wnk1 mutation died during embryonic development before day 13 of gestation. These results demonstrate that Wnk1 is a regulator of blood pressure critical for development and illustrate the utility of a functional screen driven by a sequence-based mutagenesis approach.

Animals↗
PubMed2003

Proteome analysis of Saccharomyces cerevisiae under metal stress by two-dimensional differential gel electrophoresis.

The defense mechanism by which cells combat metal stress remains poorly understood. By utilizing a newly developed technique - the differential gel electrophoresis (DIGE) - we evaluated the biological alterations of metal stress on Saccharomyces cerevisiae at its translational level. By simultaneously comparing the differential expression profiles of thousands of proteins as results of 15 different metal treatments, we were able to closely examine the response of a large number of proteins within the yeast proteome towards individual metals, as well as the response of the same proteins towards different metals. This, to our knowledge, is the first case which demonstrates the potential of DIGE as a high-throughput tool for large-scale proteome analysis. From our studies, where yeast cells were exhaustively treated with exogenous metals, 20-30% of all proteins detected showed statistically significant changes. According to different effects (up-/downregulation) of protein expression levels observed, we were able to tentatively divide the 15 metals into three groups. By mass spectrometric analysis, more than 50 protein spots were positively identified, both quantitatively and qualitatively. One of the proteins was identified to be Cu/Zn superoxide dismutase (SOD1), and its expression levels as a result of 15 different metal treatments was further examined in greater details. Significant changes in SOD1 expression were observed throughout all 15 DIGE gels.

Electrophoresis, Gel, Two-Dimensional↗
PubMed2003

[Cox regression analysis of the prognostic factors of unresectable esophageal carcinoma after stenting].

BACKGROUND & OBJECTIVE: There are many factors affect the prognosis of the patients with unresectable esophageal carcinoma who underwent intubation, however, it is unclear which ones are main causes so far. This study was designed to analyze the prognostic factors of unresectable esophageal carcinoma after stenting in order to find the reasonable modalities of palliative therapy. METHODS: Consecutive 102 patients with unresectable esophageal carcinoma who were eligible for inclusion criteria were analyzed after stenting. Twelve factors including gender, age tumor site, tumor length, stricture degree in diameter, pathologic type, grade of cell differentiation, clinical tumor stage (T, N, M), pre-stenting therapy and post-stenting therapy (radiotherapy and/or chemotherapy) were used for Cox regression model analysis. The survival rate was calculated by life table. RESULTS: The technical sucess rate of stenting was 98.3%. There were significant improvement on the grade of swallowing function (P = 0.000) and quality of life (KPS scores, P = 0.000). The incidence rate of complications was 43.1% (44/102). The survival rates of 3, 6, 9, 12 months were 67.53%, 40.59%, 27.43%, and 18.65%, respectively. The results of Cox regression showed that invasion degree of primary tumor (T, P = 0.0410) and distal metastasis (M, P = 0.006) were the statistically significant prognostic factors. The odds ratio(ORT) was 1.750 (95% CI, 0.996-3.074) on T stage of primary carcinoma, ORM was 1.527 (95% CI, 1.126-2.069) on M stage. There was no statistical significance in the survival of the patients affected by radiotherapy and/or chemotherapy after intubation. CONCLUSION: T stage and M stage are the major prognostic factors affecting the survival of patients with unresectable esophageal carcinoma after stenting. There is no benefit for survival of patients treated with radiotherapy and/or chemotherapy after intubation.

Adult↗
PubMed2003

[Giant pathologic section in the study of optimal length of surgical resection for esophageal carcinoma].

OBJECTIVE: To study the optimal surgical resection length for esophageal carcinoma. METHODS: Specimens of seventy patients with esophageal squamous cell carcinoma resected and collected in our hospital were made into pathologic giant sections. Direct intramural infiltration, multicentric carcinogenic lesion and leaping metastasis were observed in the large slice by microscope. The actual length during the operation was calculated by the ratio of shrinkage. RESULTS: Direct intramural infiltration was found in 51 (72.9%) patients, 39 proximal and 36 distal to the tumor. The mean length of direct intramural infiltration was 0.9 +/- 0.8 cm (4.0 cm maximum) proximally and 0.5 +/- 0.3 cm (2.0 cm maximum) distally. Multicentric carcinogenic lesion was found in 11 (15.7%) patients, 5 proximally, 8 distally and 2 on both sides. Proximal to the tumor, the mean distance between the multicentric carcinogenic lesion and the main lesion plus the length of the multiple carcinogenic lesion was 3.2 +/- 1.5 cm (4.7 cm maximum). Distal to the tumor, it was 3.6 +/- 2.4 cm (9.1 cm maximum). Leaping metastasis was found in 9 (12.9%) patients, 7 proximally and 4 distally. The mean distance between the leaping metastasis and the main lesion plus the length of the leaping metastatic lesion was 1.9 +/- 0.6 cm (2.9 cm maximum) proximally and 1.4 +/- 1.0 cm (2.7 cm in maximum) distally. CONCLUSION: The optimal surgical resection length for esophageal carcinoma should be at least 5 cm proximal to the tumor and total length on the distal side.

Esophageal Neoplasms↗
PubMed2003

[Primary non-Hodgkin lymphoma in the female genital system: a report of 28 cases].

OBJECTIVE: To evaluate the clinical characteristics, results of treatment, and prognostic factors of patients diagnosed as having primary female genital system lymphoma (PFGSL). METHODS: Twenty-eight cases of PFGSL were retrospectively surveyed and the clinical data of the patients were analyzed by statistic software package of SPSS10.0 for relation between clinical stage, grade, pathologic feature, treatment and prognosis. RESULTS: The median age was 44 in the cohort. It mainly involved cervix uterus, ovary and vulva. The disease had a broad range of pathologic type and 20 patients were diagnosed as suffering from B-cell by immunophenotyping, 4 patients were diagnosed as T-cell and 4 patients lesions were indefinite. According to International Working Formulation (IWF), 66.7% belonged to the intermediate-grade. The Ann Arbor stage included: Stage I(E)-12 pts (42.86%), Stage II(E)-3 pts (10.7%), Stage III(E)-1 pts (3.6%) and Stage IV-12 pts (42.86%). According to International Prognostic Index (IPI), 10 were low risk, 9 low-medium risk, 3 medium-high risk and 6 high risk, The median follow-up of the surviving patients was 2.0 years (range: 3 months-17 years), The 5-year overall survival rate was 39.3%. Most patients were given comprehensive treatment without any mode showing significant advantage over the others in survival (P = 0.2554), The involved organs, Ann Arbor stage, IWF and also IPI were significant prognostic factors for survival, CONCLUSION: The management of PFGSL should be based on comprehensive treatment including chemotherapy as the chief means. The significant prognostic factors of survival is Ann Arbor stage, IPI, IWF and the kind of involved organs.

Adolescent↗
PubMed2003

[Preparation and identification of monoclonal antibodies against CD100 molecule].

AIM: To prepare and identify the monoclonal antibodies (mAbs) against CD100. METHODS: BALB/c mice were immunized with eukaryotic expressed CD100 protein. The splenocytes from immunized mice were fused with Sp2/0 cells and the positive hybridoma clones were screened by indirect ELISA and mAbs reacting to CD100 antigen were identified by indirect immunofluorescent staining and flow cytometry with human acute T lymphoblastic leukemia cell line MOLT-4, activated human PBMC, gibbon T lymphocyte cell line MLA-144 and monkey EBV-transformed B lymphoblast cell line(BLCL). RESULTS: Seven hybridomas secreting mAbs against CD100 molecule were obtained. All the mAbs could react to natural CD100 expressed on human MOLT-4 and activated PBMCs as well as monkey BLCL cells, and six out of them could react to gibbon MLA-144 cells. CONCLUSION: A set of mAbs recognizing CD100 molecule expressed on human, monkey and gibbon cells are obtained, which may provide an useful tool for studying the structure-function relationship of CD100 molecule of human, as well as gibbon and monkey.

Animals↗
PubMed2003

[Preparation and characterization of monoclonal antibodies against human transmembrane activator and calcium modulator and cyclophilin ligand interactor].

AIM: To prepare monoclonal antibodies against human TACI and study the distribution of TACI on peripheral blood nuclear cells(PBMCs). METHODS: Murine mAbs were prepared by hybridoma technique. The distribution of TACI on PBMCs were identified by immunofluorescence staining, FCM analysis as well as immunohistochemical staining. RESULTS: Two hybridoma cell lines secreting mAbs against TACI were obtained. The titers of ascitic mAbs was 10(-7) and their Ig subclasses were IgG1. Both could recognize natural TACI on T cells. In the PHA activated models, TACI was expressed mainly on activated CD4(+) T cells. CONCLUSION: Two mAbs can recognize natural TACI, which will be of greater value in research on the structure and functions of TACI.

Animals↗
PubMed2003

[Preparation, characterization and application of monoclonal antibodies to Fc fragment of Ig fusion protein].

AIM: To prepare and characterize mAb to Fc fragment of Ig fusion protein, and to establish sandwich ELISA for detecting Ig fusion proteins and affinity chromatography method for Ig fusion protein purification. METHODS: hBCMA-Ig was used as antigen to immune BALB/c mice. The lymphocyte hybridoma technique was used to establish hybridoma cell lines stably secreting anti-Fc mAb. ELISA was employed to detect the isotype, epitopes, and species specificity of mAbs. Western blot was used to assess the reactivity between anti-Fc mAbs and denatured Ig fusion protein. LAIR1-Ig fusion protein was purified through affinity column anti-Fc mAb cross-linked to Sepharose 4B. RESULTS: Seven hybridoma cell lines(FMUFc1-FMUFc7) were acquired. A sandwich ELISA was successfully established using FMUFc4 as coating mAb and FMUFc5 as enzyme-labeled mAb. FMUFc6 could be used for Western blot. LAIR1-Ig fusion protein was effectively purified through FMUFc5-Sepharose affinity chromatography column. CONCLUSION: mAb against Fc fragment of Ig fusion protein has been prepared successfully, and methods to detect and purify Ig fusion protein are established. These mAbs provide useful tool for further application of Ig fusion protein.

Animals↗
PubMed2002

Homolog interaction during meiotic prophase I in Arabidopsis requires the SOLO DANCERS gene encoding a novel cyclin-like protein.

Interactions between homologs in meiotic prophase I, such as recombination and synapsis, are critical for proper homolog segregation and involve the coordination of several parallel events. However, few regulatory genes have been identified; in particular, it is not clear what roles the proteins similar to the mitotic cell cycle regulators might play during meiotic prophase I. We describe here the isolation and characterization of a new Arabidopsis mutant called solo dancers that exhibits a severe defect in homolog synapsis, recombination and bivalent formation in meiotic prophase I, subsequently resulting in seemingly random chromosome distribution and formation of abnormal meiotic products. We further demonstrate that the mutation affects a meiosis-specific gene encoding a novel protein of 578 amino acid residues with up to 31% amino acid sequence identity to known cyclins in the C-terminal portion. These results argue strongly that homolog interactions during meiotic prophase I require a novel meiosis-specific cyclin in Arabidopsis.

Amino Acid Sequence↗
PubMed2002

A very early induction of major vault protein accompanied by increased drug resistance in U-937 cells.

U-937 human leukemia cells were selected for resistance to doxorubicin in the presence or absence of a specific drug modulator that inhibits the activity of P-glycoprotein (Pgp), encoded by the multidrug-resistance gene (MDR1). Parental cells expressed low basal levels of the multidrug-resistance-associated gene (MRP1) and major vault protein (MVP) mRNAs and no MDR1 mRNA. Two doxorubicin-resistant cell lines were selected. Both drug-resistant cell lines upregulated the MVP mRNA level 1.5-fold within 1 cell passage. The MVP mRNA level continued to increase over time as the doxorubicin selection pressure was increased. MVP protein levels generally paralleled the mRNA levels. The 2 high molecular weight vault protein mRNAs were always expressed at constitutive levels. Fully formed vault particles consisting of the MVP, the 2 high molecular weight proteins and the vault RNA assembled and accumulated to increased levels in drug-selected cells. MVP induction is therefore the rate-limiting step for vault particle formation in U-937 cells. By passage 25 and thereafter, the selected cells were resistant to doxorubicin, etoposide, mitoxantrone and 5-fluorouracil by a pathway that was independent of MDR1, MRP1, MRP2 and breast cancer resistance protein. In summary, U-937 doxorubicin-selected cells are programmed to rapidly upregulate MVP mRNA levels, to accumulate vault particles and to become multidrug resistant.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2002

The Arabidopsis ATK1 gene is required for spindle morphogenesis in male meiosis.

The spindle plays a central role in chromosome segregation during mitosis and meiosis. In particular, various kinesins are thought to play crucial roles in spindle structure and function in both mitosis and meiosis of fungi and animals. A group of putative kinesins has been previously identified in Arabidopsis, called ATK1-ATK4 (previously known as KATA-KATD), but their in vivo functions have not been tested with genetic studies. We report here the isolation and characterization of a mutant, atk1-1, which has a defective ATK1 gene. The atk1-1 mutant was identified in a collection of Ds transposon insertion lines by its reduced fertility. Reciprocal crosses between the atk1-1 mutant and wild type showed that only male fertility was reduced, not female fertility. Molecular analyses, including revertant studies, indicated that the Ds insertion in the ATK1 gene was responsible for the fertility defect. Light microscopy revealed that, in the atk1-1 mutant, male meiosis was defective, producing an abnormal number of microspores of variable sizes. Further cytological studies indicated that meiotic chromosome segregation and spindle organization were both abnormal in the mutant. Specifically, the atk1-1 mutant male meiotic cells had spindles that were broad, unfocused and multi-axial at the poles at metaphase I, unlike the typical fusiform bipolar spindle found in the wild-type metaphase I cells. Therefore, the ATK1 gene plays a crucial role in spindle morphogenesis in male Arabidopsis meiosis.

Arabidopsis↗
PubMedDate not supplied

Conservation and divergence in the AGAMOUS subfamily of MADS-box genes: evidence of independent sub- and neofunctionalization events.

The MADS-box gene AGAMOUS (AG) plays a key role in determining floral meristem and organ identities. We identified three AG homologs, EScaAG1, EScaAG2, and EScaAGL11 from the basal eudicot Eschscholzia californica (California poppy). Phylogenetic analyses indicate that EScaAG1 and EScaAG2 are recent paralogs within the AG clade, independent of the duplication in ancestral core eudicots that gave rise to the euAG and PLENA (PLE) orthologs. EScaAGL11 is basal to core eudicot AGL11 orthologs in a clade representing an older duplication event after the divergence of the angiosperm and gymnosperm lineages. Detailed in situ hybridization experiments show that expression of EScaAG1 and EScaAG2 is similar to AG; however, both genes appear to be expressed earlier in floral development than described in the core eudicots. A thorough examination of available expression and functional data in a phylogenetic context for members of the AG and AGL11 clades reveals that gene expression has been quite variable throughout the evolutionary history of the AG subfamily and that ovule-specific expression might have evolved more than twice. Although sub- and neofunctionalization are inferred to have occurred following gene duplication, functional divergence among orthologs is evident, as is convergence, among paralogs sampled from different species. We propose that retention of multiple AG homologs in several paralogous lineages can be explained by the conservation of ancestral protein activity combined with evolutionarily labile regulation of expression in the AG and AGL11 clades such that the collective functions of the AG subfamily in stamen and carpel development are maintained following gene duplication.

Amino Acid Sequence↗