Biomedical subjects

Jing Jin

Publications and source records attributed to Jing Jin.

52 records · Page 3Linked to original sources

PubMed2004

Proteomic, functional, and domain-based analysis of in vivo 14-3-3 binding proteins involved in cytoskeletal regulation and cellular organization.

BACKGROUND: 14-3-3 proteins are abundant and conserved polypeptides that mediate the cellular effects of basophilic protein kinases through their ability to bind specific peptide motifs phosphorylated on serine or threonine. RESULTS: We have used mass spectrometry to analyze proteins that associate with 14-3-3 isoforms in HEK293 cells. This identified 170 unique 14-3-3-associated proteins, which show only modest overlap with previous 14-3-3 binding partners isolated by affinity chromatography. To explore this large set of proteins, we developed a domain-based hierarchical clustering technique that distinguishes structurally and functionally related subsets of 14-3-3 target proteins. This analysis revealed a large group of 14-3-3 binding partners that regulate cytoskeletal architecture. Inhibition of 14-3-3 phosphoprotein recognition in vivo indicates the general importance of such interactions in cellular morphology and membrane dynamics. Using tandem proteomic and biochemical approaches, we identify a phospho-dependent 14-3-3 binding site on the A kinase anchoring protein (AKAP)-Lbc, a guanine nucleotide exchange factor (GEF) for the Rho GTPase. 14-3-3 binding to AKAP-Lbc, induced by PKA, suppresses Rho activation in vivo. CONCLUSION: 14-3-3 proteins can potentially engage around 0.6% of the human proteome. Domain-based clustering has identified specific subsets of 14-3-3 targets, including numerous proteins involved in the dynamic control of cell architecture. This notion has been validated by the broad inhibition of 14-3-3 phosphorylation-dependent binding in vivo and by the specific analysis of AKAP-Lbc, a RhoGEF that is controlled by its interaction with 14-3-3.

14-3-3 Proteins↗

PubMed2004

Activation of Akt-1 (PKB-alpha) can accelerate ErbB-2-mediated mammary tumorigenesis but suppresses tumor invasion.

Elevated expression of Akt-1 (PKBalpha) has been noted in a significant percentage of primary human breast cancers. Another frequent event in the genesis of human breast cancers is amplification and overexpression of the ErbB-2 receptor tyrosine kinase, an event which is associated with activation of Akt-1. To directly assess the importance of Akt-1 activation in ErbB-2 mammary tumor progression, we interbred separate strains of transgenic mice carrying mouse mammary tumor virus/activated Akt-1 and mouse mammary tumor virus/activated ErbB-2 to derive progeny that coexpress the transgenes in the mammary epithelium. Female transgenic mice coexpressing activated Akt-1 and ErbB-2 develop multifocal mammary tumors with a significantly shorter latency period than mice expressing activated ErbB-2 alone. This dramatic acceleration of mammary tumor progression correlates with enhanced cellular proliferation, elevated Cyclin D1 protein levels, and phosphorylation of retinoblastoma protein. These bitransgenic mammary tumors also exhibit lower levels of invasion into the surrounding tissue and more differentiated phenotypes. Consistent with these observations, female mice coexpressing activated Akt-1 and ErbB-2 developed significantly fewer metastatic lesions than the activated ErbB-2 strain alone. Taken together, these observations suggest that activation of Akt-1 during ErbB-2-induced mammary tumorigenesis may have opposing effects on tumor growth and metastatic progression.

Animals↗

PubMed2004

Preliminary study on a gravity-insensitive rice mutant.

A gravity-insensitive mutant was isolated from rice (Oryza sativa L. cv. Zhonghua 11) transformed by Agrobacterium tumefaciens. The mutant's shoot growth (prostrate growth) was insensitive to gravity; whereas root growth displayed a normal positive gravitropism. Histological observation of root caps and leaf sheaths indicated that there was no significant difference in the number and size of amyloplasts in cells of the mutant and cells of the wild type.

Adaptation, Physiological↗

PubMed2004

Molecular mass and antitumor activities of sulfated derivatives of alpha-glucan from Poria cocos mycelia.

Two kinds of water-insoluble (1-->3)-alpha-D-glucan samples, ab-PCM3-I and ac-PCM3-I, isolated from different Poria cocos mycelia were sulfated, to produce two series of water-soluble derivatives ab-PCM3-I-S1-S5 and ac-PCM3-I-S1-S5, respectively. The derivatives having different weight-average molecular mass (Mw) were produced by changing reaction temperature and time as well as molar ratios between chlorosulfonic acid and number of hydroxyl groups in the glucan. The degrees of substitution (DS) of the sulfated derivatives were analyzed by elemental analysis (EA) to be 0.39-0.67 for ab-PCM3-I-S and 0.73-0.96 for ac-PCM3-I-S, respectively. The Mw and the intrinsic viscosity ([eta]) of the samples ab-PCM3-I-S and the ac-PCM3-I-S were measured by size exclusion chromatography combined with laser light scattering (SEC-LLS) and viscometry in phosphate buffer solution (PBS) at 37 degrees C. The results indicated that their Mw ranged from 2.0 to 11.3 x 10(4) for the samples ab-PCM3-I-S, and 4.7 to 40.0 x 10(4) for the samples ac-PCM3-I-S. Moreover, the antitumor activities of the sulfated derivatives ab-PCM3-I-S and ac-PCM3-I-S against Sarcoma 180 tumor cell tested both in vitro and in vivo are significantly higher than those of the native alpha-D-glucans. Therefore, a moderate range of molecular mass from 2.0 x 10(4) to 40.0 x 10(4), relatively high chain stiffness and good water solubility of the sulfated derivatives are beneficial to the enhancement of their antitumor activities.

Animals↗

PubMed2004

Central corneal thickness and its relationship to intraocular pressure in children.

OBJECTIVE: Central corneal thickness (CCT) has emerged as an important predictive factor for the development of glaucomatous damage. Although a child's cornea reaches adult thickness by the age of 3, little has been reported about normal CCT measurements in eyes of children. We wished to test the hypotheses that (1) there is a correlation between increasing CCT and increasing intraocular pressure (IOP) in the eyes of children, (2) the CCT in the eyes of children with ocular hypertension is greater than that in eyes of normal pediatric subjects, and (3) the average CCT of black children is less than that of white children. METHODS: We performed a retrospective chart review of 69 pediatric patients seen in the office of one ophthalmologist between January 1997 and December 2001 in whom CCT was measured by ultrasound pachymetry. We categorized the subjects into diagnostic groups of controls, glaucoma, glaucoma suspects, and ocular hypertension based on IOP, cup-to-disc ratio, and visual field parameters. RESULTS: The average CCT for the control patients was 555+/-37 microm; for patients with glaucoma, it was 563+/-33 microm; for glaucoma suspects, 559+/-39 microm; and for those with ocular hypertension, 595+/-39 microm. The difference between the control and ocular hypertensive groups was significant (P<0.02). The difference in CCT between the black control subjects and the white ones (537+/-36 microm vs. 564+/-28 microm) was not statistically significant (P = 0.125). CONCLUSIONS: Central corneal thickness is greater in children with ocular hypertension than in control subjects or those with glaucoma, and the values for CCT in these children correlate closely with values reported for adults. Corneas of black children may be thinner than the corneas of white children.

Adolescent↗

PubMed2004

[Effects of oxidized low-density lipoprotein on expression of type A scavenger receptor in human mesangial cells].

OBJECTIVE: To explore the regulational effect of oxidized low-density lipoprotein (Ox-LDL) on expression of type A scavenger receptor (SR-A) in human mesangial cells (HMC). METHODS: HMC line (HMCL) with high expression of SR-A (HMCL-SRA) was established after stable transfection of expressive vector with cDNA encoding SR-A. Uptake of Ox-LDL by HMCL was evaluated using Oil Red "O" staining. SR-A mRNA expression was examined using reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: More uptake of Ox-LDL was observed in the HMCL-SRA than that in the untransfected HMCL. Ox-LDL could induce SR-A mRNA expression in HMC in a dose-dependent manner, and reached a peak level after 24 h of stimulation. After 24 h of stimulation with Ox-LDL at the dose of 10, 50 and 100 micrograms/ml, SR-A mRNA expression was up-regulated to 1.35, 1.83 and 2.30-fold of controls, respectively. However, LDL had no effect on the expression of SR-A. CONCLUSIONS: It suggests that SR-A be a major binding receptor to uptake Ox-LDL in HMC. Ox-LDL may promote the progression of chronic renal diseases through up-regulation of SR-A.

Cells, Cultured↗

PubMed2004

[Exploring the possibility of a relationship between polymorphism in TIM-1 and allergic asthma in children of the Hans from Hubei province of China].

OBJECTIVE: To investigate two polymorphism sites of exon 4 in T cells, immunoglobulin domain and mucin domain protein-1 (TIM-1, also human hepatitis A virus cellular receptor-1) and to detect whether they are associated with allergic asthma in children of the Hans in Hubei province of China. METHODS: The ins/del and IVS 8+9 G/A polymorphisms in TIM-1 were detected with polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). The genotypes and alleles frequencies were calculated and analyzed. RESULTS: (1) Two alleles, a wide type del and a variant allele ins were identified in the TIM-1 exon 4. The genotype frequencies of ins/ins, ins/del, and del/del were 0.065,0.326, and 0.608 respectively in the healthy population of the Hans. Another IVS 8/9 G/A polymorphism was also found. The genotype frequencies of A/A, G/A, G/G were 0.022, 0.196 and 0.783, respectively. (2) The genotype frequencies of ins/ins, ins/del, and del/del were 0.045, 0.318, and 0.636 respectively in the allergic asthma population in children of the Hans. No significant difference in ins/del polymorphism was found between allergic asthma patients and control subjects. Another 8/9 IVS G/A polymorphism was also found. The genotype frequencies of A/A, G/A and G/G were 0.009, 0.209 and 0.782 respectively in allergic asthma. No significant difference in IVS G/A polymorphism was found between allergic asthma patients and control subjects. CONCLUSION: The genotype and allele frequencies in the two polymorphism sites in TIM-1 in healthy population of the Hans from Hubei province of China were similar to those in Japanese. The two polymorphism sites of TIM-1 are not associated with allergic asthma in Chinese children.

Adolescent↗

PubMed2004

Orthotopic liver transplantation for patients with hepatocellular carcinoma complicated by portal vein tumor thrombi.

BACKGROUND: Orthotopic liver transplantation (OLT) has been the valuable treatment of choice for patients with hepatocellular carcinoma (HCC). As the number of patients with portal vein tumor thrombi (PVTT) increases, most transplant centers become suspicious of the exact effect of the operation which has been accepted as a radical method. This study was designed to evaluate the clinical effects of OLT for patients with HCC associated with PVTT. METHODS: The follow-up of 24 patients with HCC complicated by PVTT who had received OLT (transplant group) from January 1999 to March 2003 was compared to that of 27 patients undergoing routine hepatic resection (resection group) and 59 patients without surgical treatment (non-surgical group). RESULTS: The perioperative mortality was zero for the transplant group. The 6-month, 1-year, and 2-year overall survival rates were 66.7%, 29.5% and 23.6% for the transplant group, 33.3%, 22.2% and 14.8% for the resection group (P=0.0335), and 42.1%, 24.4% and 4.1% for the non-surgical group, respectively (P=0.0316). The tumor free survival rates of recipients at 6-month, 1-year, and 2-year were 51.5%, 23.2% and zero, respectively. During the period of follow-up, the overall post-transplant intrahepatic recurrence or extrahepatic metastasis rate was 66.7% for the transplant group. CONCLUSION: OLT is an effective but palliative treatment modality for patients with HCC associated with PVTT followed by a prolonged survival but a poor tumor free survival rate.

Budd-Chiari Syndrome↗

PubMed2003

3-deoxy-3,3-difluoro-D-arabinofuranose: first stereoselective synthesis and application in preparation of gem-difluorinated sugar nucleosides.

The design and synthesis of gem-difluorinated sugar nucleosides were described. The key intermediate, 3-deoxy-3,3-difluoro-d-arabinofuranose 9, was first stereoselectively prepared from the chiral gem-difluorohomoallyl alcohol 12. The kinetic formation of single anti-14 in the benzylation of 12 could be accomplished by controlling the amount of sodium hydride used. The dihydroxylation of 14 (a mixture of anti and syn isomers) followed by deprotection and oxidation stereoselectively afforded furanose 9 with the arabino configuration at the C2 position. N(1)-(3-Deoxy-3,3-difluoro-beta-D-arabinofuranosyl)cytosine 6 was prepared from 9 by the glycosylation reaction. 4'-Thiofuranose 25 was easily synthesized from 9. The oxidation of 25 followed by the condensation with silylated N(4)-benzoylcytosine (Pummerer reaction) failed to give our desired protected nucleoside l-3'-deoxy-3',3'-difluoro- 4'-thiocytidine 27', but the regioisomer 27 was obtained. The regiochemistry of the Pummerer reaction was determined by the kinetic acidity of the alpha-proton of 4'-thiofuranose 25.

Arabinose↗

PubMed2003

Aqueous shunt devices compared with trabeculectomy with Mitomycin-C for children in the first two years of life.

PURPOSE: To compare the outcomes of children 24 months of age or younger treated with aqueous shunt devices or with mitomycin-C (MMC) trabeculectomy. DESIGN: Retrospective, age-matched, comparative case series. METHODS: Forty-six eyes of 32 patients with mean age of 7.0 +/- 5.1 month (range, 1 to 22 months) and uncontrolled glaucoma, which received an aqueous shunt device (Ahmed glaucoma valve or Baerveldt implant), compared with 24 eyes of 19 patients with mean age of 5.3 +/- 4.8 months (range, 0.5 to 24 months), which received an MMC trabeculectomy. Surgical success was defined as intraocular pressure < 23 mm Hg on maximal glaucoma medication, no further glaucoma surgery performed or recommended, no devastating complication, and stable ocular dimensions (axial length and corneal diameter). RESULTS: Cumulative probabilities of success were 87% +/- 5.0% for the aqueous shunt group compared with 36% +/- 8.0% success in the trabeculectomy group at 12 months and 53% +/- 12% in the aqueous shunt group compared with 19% +/- 7% in the trabeculectomy group at 72 months (chi(2) of 23.5, P <.0001). Aqueous shunt implantation was associated with significantly more postoperative complications requiring a return to the operating room (21 of 46 eyes, 45.7%) compared with trabeculectomy with MMC (3 of 24 eyes, 12.5%, P =.0074). The most common postoperative procedure in the aqueous shunt group was tube repositioning, performed in 16 of 46 eyes (34.8%). CONCLUSIONS: Aqueous shunt implantation offers a significantly greater chance of successful glaucoma control in the first 2 years of life, compared with trabeculectomy with MMC. However, the enhanced success with aqueous shunt devices is associated with a higher likelihood of postoperative complications requiring surgical revision, most commonly tube repositioning.

Antibiotics, Antineoplastic↗

PubMed2003

[Observation amyloplasts in the gravity-insensitive mutant of rice under gravity and microgravity conditions].

Using histochemistry and optical microscope, we examined the number and the size of amyloplasts in specialized tissues of gravitropically receptive organs-tissues such as the coleoptile and sheath of rice mutant (insensitive to gravity) and wide type (Oryza sativa L. subsp. japonica) (Zhonghua 11). We found there was no statistical difference between the mutant and wide type, both of which grew on earth or on the clinostat respectively. On earth, it was found that amyloplasts sedimented at the distal end of each cell of the special starch sheath tissues and re-sedimentation of amyloplasts toward the direction of gravity was almost completed in 5 minutes after inverting the seedlings. On the clinostat, amyloplasts dispersed in the starch sheath tissue. Such observations indicated that the mutation was not resulted from the starch-deficiency or starch-absence, the further research is going on.

Gravitation↗

PubMed2002

Analysis of prognostic factors for T(1)N(0)M(0) glottic cancer treated with definitive radiotherapy alone: experience of the cancer hospital of Peking Union Medical College and the Chinese Academy Of Medical Sciences.

PURPOSE: To analyze the prognostic factors for early-stage glottic cancer (T(1)N(0)M(0)) treated with radiotherapy alone. METHODS AND MATERIALS: Between 1958 and 1994, 238 patients (220 male) with T(1)N(0)M(0) (UICC 1997) squamous cell carcinoma of the glottis were treated with 6- or 8 MV X-ray or 60Co radiation in parallel-opposed fields (median size: 22.5 cm(2)) over a median of 52 days to a median dose of 68 Gy. Locoregional control (LC) and overall survival (OS) were estimated by the Kaplan-Meier method. Log-rank and Cox regression analyses were used to identify prognostic factors. RESULTS: The median follow-up time was 127 months (range: 4-410 months). Five- and 10-year OS rates were 84.0% and 74.9%. The 5-year LC rate was 82.2%. Forty-four patients had recurrent disease (41 locally, 2 in cervical lymph nodes, 1 lost to follow-up); 23 had second malignancies. On multivariate analysis, unfavorable prognostic factors for OS were age >65 years (p < 0.001) and second malignancy (p < 0.001). Unfavorable prognostic factors for LC were bulky tumor (p = 0.023), anterior commissure involvement (p = 0.024), and decrease in hemoglobin during treatment (p = 0.025). CONCLUSIONS: Radiotherapy alone provides good control of early-stage glottic cancer. Bulky tumor, anterior commissure involvement, and decreasing hemoglobin are negative prognostic factors for LC.

Adult↗

PubMed2002

DNA immunization with fusion genes encoding different regions of hepatitis C virus E2 fused to the gene for hepatitis B surface antigen elicits immune responses to both HCV and HBV.

AIM: Both Hepatitis B virus (HBV) and Hepatitis C virus (HCV) are major causative agents of transfusion-associated and community-acquired hepatitis worldwide. Development of a HCV vaccine as well as more effective HBV vaccines is an urgent task. DNA immunization provides a promising approach to elicit protective humoral and cellular immune responses against viral infection. The aim of this study is to achieve immune responses against both HCV and HBV by DNA immunization with fusion constructs comprising various HCV E2 gene fragments fused to HBsAg gene of HBV. METHODS: C57BL/6 mice were immunized with plasmid DNA expressing five fragments of HCV E2 fused to the gene for HBsAg respectively. After one primary and one boosting immunizations, antibodies against HCV E2 and HBsAg were tested and subtyped in ELISA. Splenic cytokine expression of IFN-gamma and IL-10 was analyzed using an RT-PCR assay. Post-immune mouse antisera also were tested for their ability to capture HCV viruses in the serum of a hepatitis C patient in vitro. RESULTS: After immunization, antibodies against both HBsAg and HCV E2 were detected in mouse sera, with IgG2a being the dominant immunoglobulin sub-class. High-level expression of INF-gamma was detected in cultured splenic cells. Mouse antisera against three of the five fusion constructs were able to capture HCV viruses in an in vitro assay. CONCLUSION: The results indicate that these fusion constructs could efficiently elicit humoral and Th1 dominant cellular immune responses against both HBV S and HCV E2 antigens in DNA-immunized mice. They thus could serve as candidates for a bivalent vaccine against HBV and HCV infection. In addition, the capacity of mouse antisera against three of the five fusion constructs to capture HCV viruses in vitro suggested that neutralizing epitopes may be present in other regions of E2 besides the hypervariable region 1.

Animals↗

PubMed2002

Mechanism of 5-fluorouracil required resistance in human hepatocellular carcinoma cell line Bel(7402).

AIM: To investigate the resistance mechanism of 5-fluorouracil (5-FU) in Bel(7402)/5-FU cells which was established in our lab by in vitro continuous stepwise exposure of human hepatocellular carcinoma (HCC) cell line Bel(7402) to 5-FU. METHODS: The expression of multidrug resistance-associated protein (MRP) and thymidylate synthase (TS) in Bel(7402) cells was detected by immonocytochemistry. The fluorescein (FLU) accumulation, an index of MRP functional activity, was determined by flow cytometry. The distribution of FLU was observed by confocal laser scanning microscope. The spectrofluorometry was used to show the intracelluar content of glutathione (GSH). Cell growth inhibition was determined by MTT assay. The activity of glutathione S-transferases (GSTs) was determined by spectrophotometry. RESULTS: A higher expression of MRP in the Bel(7402)/5-FU cells was observed by using monoclonal mouse anti-MRP antibody, MRPr-1, in comparison with Bel(7402) cells. Bel(7402)/5-FU cells also showed a significant decrease of FLU accumulation. FLU mainly accumulated in the nucleus with a high nuclear/cytoplasmic ratio in Bel(7402) cells, whereas there was no difference of FLU accumulation between the nucleus and cytoplasm in Bel(7402)/5-FU cells. The intracellular GSH content in Bel(7402)/5-FU cells was almost 3 folds higher than that in Bel(7402) cells. Addition of D, L-buthione-S, R-sulfoximine (BSO) dose-dependently reduced the GSH content in Bel(7402)/5-FU cells, however, only a weak enhancement on the cytotoxicity of 5-FU and doxorubicin (Dox) to Bel(7402)/5-FU cells was observed. Bel(7402)/5-FU cells also exhibited 29.1 % higher total GSTs activity than Bel(7402) cells. Immunocytochemical staining by using anti-TS monoclonal antibody TS 106 showed that the level of TS in Bel(7402)/5-FU cells elevated markedly as compared with Bel(7402) cells. CONCLUSION: The continuous exposure of Bel(7402) cells to 5-FU led to overexpression of TS and MRP, as well as increased intracellular GSH content and total GST activity.

Buthionine Sulfoximine↗

PubMed2002

[Audiological characteristics of auditory neuropathy].

OBJECTIVE: To study the auditory electrophysiological characteristics of the auditory neuropathy. METHODS: Ten patients were diagnosed as auditory neuropathy. The history, pure tone audiometry, stapedial reflex, auditory brainstem response, electrocochleogram, distortion product otoacoustic emission and his contralateral suppression of white noise, middle latency response and slow cortical response were assessed. Five patients were investigated with brain CT or MRI. RESULTS: The patients were of both genders. The average age was 20.3 years old and most of them were teenagers. Nine patients complained of bilaterally hearing impairment, while one patient who did not complain of hearing loss had a tinnitus of both ears. The pure tone audiogram showed a middle or moderate sensorineural hearing loss at low frequencies 0.5 kHz and/or 0.25 kHz in nineteen ears but a normal audiogram in one ear. Stapedial reflex was absent in nineteen ears, and threshold elevated in one ear while his pure tone audiogram revealed an ascending curve. Auditory brainstem response cannot be recorded or only wave V or/and wave I presented. All of the patients were evoked a distortion product OAE, which cannot be suppressed by contralateral white noise. Electrocochleogram demonstrated AP absent or very small amplitude in most ear and the--SP amplitude were 0.595 microV, while they had a normal slow cortical response but except one patient presented normal middle latency response. The findings of CT or MRI were normal. CONCLUSION: The pure tone audiogram could preserve unchanged at early stage of auditory neuropathy, but their stapedial reflex and auditory brainstem response are absent or threshold elevated. The precise pathologic site of this disorder is yet to be defined, but it may locate in the auditory system below brainstem.

Adolescent↗

PubMed2000

Purification and Characterization of Recombinant Hepatitis B Virus Surface Antigen SS1 Expressed in Pichia pastoris.

The purification of recombinant hepatitis B surface antigen, SS1 protein, expressed in Pichia pastoris, and the investigation of its physiochemical characters and immunogenicity were described here. Employing McAb immunoaffinity chromatography, this protein was purified to purity of 95%. The results of ELISA and Western blotting showed good antigenicity of this purified SS1 protein. CsCl gradient centrifugation and electron microscopy assay proved that this purified protein could be assembled into particles similar to the HBV subviral particles. Strong antibody responses against both the HBs and PreS1 epitopes were induced in BALB/c mice immunized with this purified protein. The simultaneous injection of a CpG adjuvant induced a Th1-like immune response against both the HBs and PreS1 epitopes.

Journal Article↗