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Jun Shi

Publications and source records attributed to Jun Shi.

At least 37 records · Page 2Linked to original sources
PubMed2006

[Design of the Medical Digital Assistant for "bottom of the pyramid"].

To meet the challenges such as raising the efficiency of medical resources, slowing the fastly-increasing medical costs and keeping the sustainability of the aging society and chronic diseases, this paper introduces a Medical Digital Assistant system for "BOP", which includes a mobile monitoring unit,a data transferring unit, and a managing unit, and presents the system's evaluating method. In addition, a new application model and the service workflow are discussed.

Computer Communication Networks↗
PubMed2006

[Intratympanic dexamethasone medication for sudden sensorineural hearing loss: clinical evaluation].

OBJECTIVE: To investigate clinical efficacy of intratympanic dexamethasone injection for sudden sensorineural hearing loss. METHOD: Subjects received an course of at least 7-day dexamethasone [5 g/(L x d)] intratympanic injection. Pure-tone averages (PTA) calculated using air conduction thresholds at 4 -frequencies (500, 1000, 2000, 4000 Hz) at pre-injection and post-injection were compared. The change in PTA greater than 10 dB HL was considered to be effective. RESULT: PTA at pre-injection and post-injection were (65.65 +/- 24.73) dB HL and (50.25 +/- 25.59)dB HL respectively in 21 patients with sudden sensorineural hearing loss. There was significant improvement in PTA (P < 0.01). Improvement in hearing was found in 47.6% patients. Promising results of intratympanic dexamethasone medication were found in cases with shorter duration or/and without vertigo. No unexpected adverse events such as otitis media or perforated tympanic membrane or worsening in hearing occurred during the injection or follow-up period. CONCLUSION: Intratympanic dexamethasone medication can be beneficial in treating patient with sudden sensorineural hearing loss. Duration and vertigo are two important factors for prognosis.

Adult↗
PubMed2006

[Spectral analysis of transient species of quinoline degradation].

Quinoline's degradation was studied by pulse radiolysis. It was found that hydrated electron, hydrogen radical, hydroxyl radical and SO4*- can react with quinoline. The absorption spectra of the transient species of quinoline were obtained, and related constants were determined, but it was found that the species of Br2*- and N3*- can't react with quinoline. The results give us some advices for studing the degradation of quinoline.

Electrons↗
PubMed2006

[Wireless medical monitoring--current status and developments].

Wireless medical monitoring overcomes the limitations of conventional wired-monitoring, enabling people to get their physiological and pathological informations anytime and anywhere. This review summarizes the basic components and principles of wireless medical monitoring, including the techniques for measuring and transmitting vital signs. Its status,developments in R&D and applications are presented with a series of examples. Limitations and potential uses of wireless medical monitoring are also discussed.

Computer Communication Networks↗
PubMed2005

Ryk-mediated Wnt repulsion regulates posterior-directed growth of corticospinal tract.

Guidance cues along the longitudinal axis of the CNS are poorly understood. Wnt proteins attract ascending somatosensory axons to project from the spinal cord to the brain. Here we show that Wnt proteins repel corticospinal tract (CST) axons in the opposite direction. Several Wnt genes were found to be expressed in the mouse spinal cord gray matter, cupping the dorsal funiculus, in an anterior-to-posterior decreasing gradient along the cervical and thoracic cord. Wnts repelled CST axons in collagen gel assays through a conserved high-affinity receptor, Ryk, which is expressed in CST axons. Neonatal spinal cord secretes diffusible repellent(s) in an anterior-posterior graded fashion, with anterior cord being stronger, and the repulsive activity was blocked by antibodies to Ryk (anti-Ryk). Intrathecal injection of anti-Ryk blocked the posterior growth of CST axons. Therefore, Wnt proteins may have a general role in anterior-posterior guidance of multiple classes of axons.

Animals↗
PubMed2005

Population pharmacokinetics of the active metabolite of leflunomide in pediatric subjects with polyarticular course juvenile rheumatoid arthritis.

Leflunomide is a pyrimidine synthesis inhibitor used in the treatment of rheumatoid arthritis. Data from two clinical studies were used to establish a population pharmacokinetic (PPK) model for the active metabolite (M1) of leflunomide in patients with juvenile rheumatoid arthritis (JRA) and determine appropriate pediatric doses. Seventy-three subjects 3-17 years of age provided 674 M1 concentrations. The PPK model was derived from nonlinear mixed-effects modeling and qualified by cross-study evaluation and predictive check. A one-compartment model with first-order input described M1 PPK well. Body weight (WT) correlated weakly with oral clearance (CL/F = 0.020.[WT/40](0.430)) and strongly with volume of distribution (V/F = 5.8.[WT/40](0.769)). Steady-state concentrations (C(ss)) of M1 in JRA were compared for a variety of leflunomide dose regimens using Monte-Carlo simulation. To achieve comparable C(ss) values in pediatric patients with JRA to that in adult patients, doses of leflunomide should be adjusted modestly: 10 mg/d for 10-20 kg, 15 mg/d for 20-40 kg, and 20 mg/d for > 40 kg.

Adolescent↗
PubMed2005

Sortilin is essential and sufficient for the formation of Glut4 storage vesicles in 3T3-L1 adipocytes.

Impaired translocation of the glucose transporter isoform 4 (Glut4) to the plasma membrane in fat and skeletal muscle cells may represent a primary defect in the development of type 2 diabetes mellitus. Glut4 is localized in specialized storage vesicles (GSVs), the biological nature and biogenesis of which are not known. Here, we report that GSVs are formed in differentiating 3T3-L1 adipocytes upon induction of sortilin on day 2 of differentiation. Forced expression of Glut4 prior to induction of sortilin leads to rapid degradation of the transporter, whereas overexpression of sortilin increases formation of GSVs and stimulates insulin-regulated glucose uptake. Knockdown of sortilin decreases both formation of GSVs and insulin-regulated glucose uptake. Finally, we have reconstituted functional GSVs in undifferentiated cells by double transfection of Glut4 and sortilin. Thus, sortilin is not only essential, but also sufficient for biogenesis of GSVs and acquisition of insulin responsiveness in adipose cells.

3T3-L1 Cells↗
PubMed2005

Activated human umbilical cord blood dendritic cells kill tumor cells without damaging normal hematological progenitor cells.

Apart from their role as antigen presenting cells, human peripheral blood monocyte and CD34+ cell-derived dendritic cells (DC), have been demonstrated to exert cytotoxicity against some tumor cells, and their tumoricidal activity can be enhanced by some stimili. However, there have been no reports concerning the tumoricidal activity of human cord blood dendritic cells (CBDC). In this article, we report that human cord blood monocyte-derived DC acquire the ability to kill hematological tumor cells, after activation with lipopolysaccharide (LPS) or gamma-interferon (IFN-gamma), associated with the enhanced TNF-alpha-related apoptosis-inducing ligand (TRAIL) expression in CBDC cytoplasm. The CD14-positive cells collected from cord blood were induced to CBDC in vitro. After activation with IFN-gamma for 12 h, CBDC exhibited cytotoxicity against HL60 and Jurkat cells, while activation with LPS induced cytotoxicity against Daudi and Jurkat cells. However, both LPS- and IFN-gamma-stimulated CBDC showed no cytotoxic activity against normal CD14-negative cord blood mononuclear cells. The formation of umbilical cord hematopoietic progenitor colonies, identified as burst-forming unit-erythroid and colony-forming unit granulocyte-macrophage, was not inhibited by stimulated or unstimulated CBDC. IFN-gamma or LPS stimulation enhanced intracellular but not cellular surface TRAIL, and neither intracellular nor cellular surface tumor necrosing factor-alpha and Fas Ligand as analyzed by flow cytometry. Our results show that activated CBDC can serve as cytotoxic cells against hematological tumor cells without damaging the normal hematopoietic progenitor cells.

Antigens, CD34↗
PubMed2005

Pharmacokinetics of telithromycin: application to dosing in the treatment of community-acquired respiratory tract infections.

INTRODUCTION: Telithromycin is the first ketolide anti bacterial approved for treating community-acquired pneumonia, acute exacerbations of chronic bronchitis, and acute bacterial sinusitis in adults. The purpose of this article is to review the main pharmacokinetic properties of telithromycin and their application to the treatment of these infections. METHODS: Sources of information were identified through a Medline search (up to March 2005). MAIN FINDINGS: The absolute oral bioavailability of telithromycin is approximately 57%, which is unaffected by food intake. At the recommended 800 mg once-daily oral dosing regimen, telithromycin reaches a steady-state concentration of approximately 2 microg/mL in plasma and has an elimination half-life of approximately 10 hours. Telithromycin shows extensive tissue distribution and penetrates effectively into bronchopulmonary tissue and epithelial lining fluid. Since elimination of telithromycin occurs via multiple pathways--the highest proportion (70%) through metabolism--impairment of a single pathway has a limited impact on telithromycin exposure. Dose adjustments are unnecessary in elderly patients or in individuals with hepatic impairment or mild to moderate renal impairment. A reduced dose could be recommended in patients with severe renal impairment. Telithromycin is metabolized primarily in the liver, approximately half of which is via the cytochrome P450 (CYP) 3A4 system. Telithromycin AUC(0-24 h) increased by 1.5- to 2.0-fold in the presence of itraconazole and ketoconazole. Administration of telithromycin with drugs metabolized via CYP3A4 may result in increased exposure to the co-administered drug, as shown for simvastatin (5.3-fold) and midazolam (6-fold). Co-administration of telithromycin minimally increases (1.2- to 1.4-fold) exposure to theophylline, digoxin, and metoprolol. Although telithromycin does not affect the pharmacokinetics of warfarin, consideration should be given to monitoring prothrombin times/INR in patients receiving telithromycin and oral anticoagulants simultaneously. CONCLUSION: Overall, the pharmacokinetic/pharmaco dynamic properties of telithromycin indicate that this ketolide antibacterial is a valuable and convenient treatment option for community-acquired respiratory tract infections.

Aged↗
PubMed2005

Effects of itraconazole or grapefruit juice on the pharmacokinetics of telithromycin.

STUDY OBJECTIVE: To determine whether coadministration of the cytochrome P450 3A4 (CYP3A4) inhibitors itraconazole or grapefruit juice will modify the pharmacokinetic profile of telithromycin, and to assess the safety of telithromycin. DESIGN: Two single-center, open-label studies; the itraconazole study was nonrandomized, sequential, and multiple dose, and the grapefruit juice study was randomized, two-period crossover, and single dose. SETTING: Two clinical investigative centers in the United States. SUBJECTS: Thirty-four healthy, nonsmoking male volunteers aged 18-45 years. INTERVENTION: All patients received telithromycin 800 mg/day; 18 patients received concomitant itraconazole 200 mg/day, and 16 received concomitant single-dose, single-strength grapefruit juice. MEASUREMENTS AND MAIN RESULTS: Standard pharmacokinetic and safety measurements were performed. Itraconazole given concomitantly with telithromycin increased the steady-state area under the plasma concentration-time curve from 0-24 hours of telithromycin by 53.8% (p<0.0001). Coadministration of grapefruit juice did not affect telithromycin pharmacokinetic parameters, and telithromycin was well tolerated in both studies. CONCLUSION: Only modest changes in the pharmacokinetics of telithromycin were seen with concomitant administration of itraconazole. Telithromycin pharmacokinetics were unaffected by concomitant administration of grapefruit juice.

Administration, Oral↗
PubMed2005

Pharmacodynamic analysis of the microbiological efficacy of telithromycin in patients with community-acquired pneumonia.

BACKGROUND AND OBJECTIVE: Telithromycin, a ketolide antibacterial, demonstrates concentration-dependent bactericidal activity against the major pathogens causing community-acquired respiratory tract infections. The objective of this study was to explore the relationships between pharmacokinetic/pharmacodynamic predictor variables, such as area under the plasma concentration-time curve (AUC) over minimum inhibitory concentration (MIC) [AUC/MIC], maximum plasma concentration (C(max)) over MIC (C(max)/MIC) and microbiological outcome from telithromycin therapy for community-acquired pneumonia (CAP). PATIENTS AND METHODS: Data were pooled from five phase III studies of oral telithromycin (800 mg once daily for 7-10 days) for the outpatient treatment of adults with CAP. Only subjects with a single pathogen isolated at baseline, a telithromycin MIC determination and at least one plasma pharmacokinetic sample were included. Bacteriologically modified intent-to-treat (bmITT) and bacteriologically evaluable per protocol (PPb) populations were analysed. Individual AUC and C(max) Bayesian estimates were obtained with a population pharmacokinetic model. Logistic regression, nonparametric smoothing, and classification analysis and regression tree (CART) were used to assess the relationship between AUC/MIC and C(max)/MIC and microbiological outcome by pathogen. RESULTS: The bmITT population included 224 patients (Streptococcus pneumoniae in 113, Haemophilus influenzae in 89 and Staphylococcus aureus in 22). Median telithromycin MIC was 0.015 microg/mL for S. pneumoniae, 2.0 microg/mL for H. influenzae and 0.12 microg/mL for S. aureus, with median AUC/MIC of 907.1, 6.9 and 98.4, and median C(max)/MIC of 172.0, 1.3 and 20.4 for the three pathogens, respectively. Both logistic regression and nonparametric smoothing showed the probability of microbiological cure to be consistently greater than 90% over the observed range of predictor variables. No reliable AUC/MIC or C(max)/MIC breakpoints were identified by CART. CONCLUSION: Telithromycin exhibits near-maximal efficacy against three major pathogens causing CAP at a dose of 800 mg once daily.

Adolescent↗
PubMed2005

Clinical pharmacokinetics of telithromycin, the first ketolide antibacterial.

Telithromycin is the first ketolide, which is a new class of antibacterial agents related to the macrolides that have structural modifications permitting dual binding to bacterial ribosomal RNA so that activity is retained against Streptococcus pneumoniae with macrolide-lincosamide-streptogramin(B) resistance. Clinical experience in infectious patients has shown that oral telithromycin 800mg once daily for 5-10 days is effective for the treatment of community-acquired upper and lower respiratory tract infections. Absorption of telithromycin in humans is estimated to be > or = 90%. Prior to entering the systemic circulation, telithromycin undergoes first-pass metabolism (mainly by the liver). Its absolute bioavailability is 57% and is unaffected by food. The volume of distribution of telithromycin after intravenous infusion is 2.9 L/kg. Telithromycin is 60-70% bound to serum proteins and has extensive diffusion into a range of target biological tissues, achieving concentrations above its minimum inhibitory concentration (MIC) against key respiratory pathogens throughout the dosing interval. After entering the systemic circulation, telithromycin is eliminated by multiple pathways (7% by biliary and/or intestinal excretion, 13% by renal excretion and 37% by hepatic metabolism). Telithromycin is metabolised via cytochrome P450 (CYP) 3A4 and non-CYP pathways. The identified metabolites show minimal antibacterial activity compared with the parent drug. In healthy subjects receiving telithromycin 800 mg once daily, the peak plasma concentration achieved is 2.27 microg/mL. Plasma concentrations of telithromycin show a biphasic decrease over time, with an initial disposition half-life of 2.9 hours and a terminal elimination half-life of approximately 10 hours after multiple dose administration. Steady-state plasma concentrations are achieved within 2-3 days of once-daily administration. Owing to elimination by multiple pathways there is a small increase in exposure when one of these elimination pathways is impaired, as indicated by the results of studies in special patient populations (e.g. those with hepatic or renal impairment). Dosage reductions may be recommended in patients with severe renal impairment. Inhibition of CYP3A4 by potent inhibitors such as itraconazole and ketoconazole results in a 54% and 95% increase in telithromycin area under the plasma concentration-time curve, respectively. The potential for telithromycin to inhibit the CYP3A4 pathway is similar to that of clarithromycin. The once-daily administration of telithromycin is likely to limit the potential for drug interactions and clinically significant increases in exposure. In phase III clinical trials, the telithromycin 800 mg once-daily dose has been shown to provide close to the maximum antimicrobial activity against S. pneumoniae, Haemophilus influenzae and Staphylococcus aureus in patients with community-acquired pneumonia. In conclusion, telithromycin has a well characterised and reproducible pharmacokinetic profile, with pharmacokinetic/pharmacodynamic relationships supporting an oral dosage regimen of 800 mg once daily.

Absorption↗
PubMed2005

[Evaluation of mastication function after three-dimensional maxillary reconstruction].

OBJECTIVE: To evaluate the mastication function of the patient whose maxilla was reconstructed with individual titanium mesh and Chinese flap or combined with fibular flap. The superiority of this method on maxillary functional reconstruction was testified. METHODS: Since March of 2001, 10 cases of maxillary defect were reconstructed with individual titanium mesh and Chinese flap or combined with fibular flap, and routine removal partial dentures were fixed after 3 - 6 months postoperatively. Assessment of occlusal force was proceeded by T-Scan II system (Tekscan company, USA). RESULTS: The occlusal force analysis results indicated the asymmetry index of bite force and asymmetry index of occlusal contact area differed significantly between preoperation and postopertion (P < 0.05). The recovery rate of total occlusal force was between 27.05%-74.06%, and the average was 50.15%. CONCLUSION: This new three-dimensional maxillary functional reconstruction method had a satisfactory recovery in both of contour and function recently, especially restored the mastication function effectively.

Humans↗
PubMed2005

[Expression of cell cycle control genes in myelodysplastic syndromes].

OBJECTIVE: To study aberrant expression of cell cycle control genes in patients with myelodysplastic syndromes (MDS). METHODS: Reverse transcription polymerase chain reaction (RT-PCR) was used to investigate the expression of cell cycle control genes (cyclin D2, cyclin D3, cyclin A1, cyclin E, CDK2, CDK4, CDK6, p21, p27, p57, Rb and E2F1) in bone marrow mononuclear cells (BMMNCs) from 29 normal control, 27 MDS and 19 de novo acute myeloid leukemia (AML). RESULTS: The expression levels of cyclin D3 (0.65 +/- 0.17, P < 0.05) and cyclin A1 (0.48 +/- 0.04, P < 0.05) in MDS were higher than those in normal control and significantly lower than those in AML. The expression rates and levels of cyclin D2 (40.7% and 0.78 +/- 0.21) and cyclin E (51.9% and 0.52 +/- 0.10) in MDS were statistically higher than those in normal control and AML. The expression level of CDK2 in MDS (0.66 +/- 0.19, P < 0.01) was higher than that in normal control (0.42 +/- 0.04) and the expression rate of CDK6 in MDS (25.9%) higher than in normal control (3.4%, P < 0.05). There was no significant difference of the expression rates and levels of CDK4 in MDS, AML and normal control. The expression rates and levels of p21 (77.8% and 1.18 +/- 0.21) and p27 (48.1% and 1.14 +/- 0.40) in MDS were statistically higher than those in normal control and AML. The expression level of p57 in MDS (0.69 +/- 0.06) was higher than that (0.53 +/- 0.05, P < 0.01) in normal control but lower than in AML (0.96 +/- 0.16, P < 0.01). The expression rate (55.6%) and level (0.85 +/- 0.17) of Rb in MDS were significantly higher than those in normal control and AML. The expression rate (7.4%) and level (0.39 +/- 0.04) of E2F1 in MDS were comparable to those in normal control but lower than those in AML. CONCLUSION: MDS clones have aberrant mechanism of cell cycle control: high expressions of cyclin family members, CDK2 and CDK6 may lead to high proliferation; high expression of p21 and p27 may cause the G1 phase arrest.

Adolescent↗
PubMed2005

[The response of bone marrow hematopoietic cells to G-CSF in paroxysmal nocturnal hemoglobinuria patients].

OBJECTIVE: To study the response of hematopoietic cells (HSC) to granulocyte colony stimulating factor (G-CSF) in paroxysmal nocturnal hemoglobinuria (PNH) patients. METHODS: (1) Bone marrow mononuclear cells (BMMNC) from 17 PNH patients and 12 normal subjects were inoculated into semisolid culture media containing or not G-CSF (50 ng/ml). The cluster/colony forming unit-granulocyte/monocyte (CFU/cFU-GM) were counted and compared. (2) BMMNC of 20 PNH patients and 12 normal controls were triply stained for CD34, CD59 and G-CSF receptor CD114/stem cell factor receptor (C-KIT) CD117 and assessed by FCM. The CD34(+) cells were identified as CD34(+)/CD59(+) and CD34(+)/CD59(-). Percentage of CD114 and CD117 expression in each cell population was calculated. RESULTS: (1) PNH cFU-GM without G-CSF were (112.41 +/- 22.74)/10(5) BMMNC, while with G-CSF: (133.82 +/- 25.85)/10(5) BMMNC and normal cFU-GM were (190.33 +/- 36.05)/10(5) BMMNC, (309.42 +/- 92.94)/10(5) BMMNC, respectively. Whether with or without G-CSF, PNH BMMNC formed less cFU-GM than control did, both of the two kinds of BMMNC responded to G-CSF well (P < 0.05), but the increment of PNH cFU-GM yields was less than that of the normal control (P < 0.05). CFU-GM yields of PNH BMMNC without G-CSF were (24.29 +/- 9.05)/10(5) BMMNC, with G-CSF were (27.53 +/- 10.65)/10(5) BMMNC, while normal control were (77.42 +/- 36.01)/10(5) BMMNC and (98.00 +/- 43.14)/10(5) BMMNC, respectively. Whether with or without G-CSF, PNH BMMNC showed less CFU-GM yields than that of control (P < 0.05). (2) The percentage of CD114 positive cells in PNH CD34(+)CD59(+) BMMNC was (73.34 +/- 29.40)% and that in PNH CD34(+)CD59(-) BMMNC and in control CD34(+)CD59(+) BMMNC were (32.70 +/- 6.89)% and (58.52 +/- 29.99)%, respectively. The percentage of CD114 expression in PNH CD34(+) CD59(-) BMMNC was less than that in the other two groups (P < 0.05). The percentages of CD117 positivities on the PNH CD34(+)CD59(+) BMMNC were (76.90 +/- 22.08)%, PNH CD34(+) CD59(-) (36.03 +/- 7.69)% and control CD34(+) CD59(+) (80.28 +/- 13.36)%, respectively (P < 0.01). CONCLUSION: In vitro, BMMNC of normal control grow better, and respond better to G-CSF than PNH BMMNC do. PNH CD34(+)CD59(-) BMMNC express less G-CSF receptor and C-KIT than PNH CD34(+)CD59(+) and normal CD34(+)CD59(+) BMMNC do, which may be the reason that abnormal PNH clone grow worse than the normal clones do.

Adolescent↗
PubMed2005

[The clinical features of hepatitis associated aplastic anemia].

OBJECTIVE: To analyse the proportion of hepatitis associated aplastic anemia (HAAA) in severe aplastic anemia (SAA) and its clinical features of HAAA. METHODS: All newly diagnosed SAA cases in our department in the recent 5 years were analyzed. A case-control study was undertaken to investigate the differences of clinical and laboratory features between HAAA and non-hepatitis associated SAA (non-HASAA) patients. RESULTS: The proportion of HAAA in SAA was 3.3%. There was no significant difference in PB cell counts, bone marrow hematopoiesis status and the amount of blood transfusion between HAAA and non-HASAA patients. Sera from 13 patients with HAAA were tested for antibodies to hepatitis viruses A, B, and C and hepatitis B surface antigen. Twelve (92.3%) of them had negative serologic results for the tests and only one (7.7%) had a positive result for HBsAg and HBeAg. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were decreased prior to the diagnosis in twelve (92.3%) of the 13 HAAA patients. The percentage of CD4(+) cells in HAAA patients was significantly lower than that in non-HASAA patients (P < 0.05). HAAA patients had higher percentages of CD8(+) cells (P < 0.05) and lower ratios of CD4(+)/CD8(+) (P < 0.05). The early infection rate of the HAAA patients was significantly higher than that of non-HASAA patients (84.6% vs 42.3%, P < 0.05), with different mortalities (61.5% vs 15.4%, P < 0.05). The 2-year survival rate of HAAA patients was significantly lower than that of non-HASAA patients (16.6% vs 83.2%, P < 0.01). CONCLUSION: The proportion of HAAA in SAA was 3.3%. Most of HAAA were associated with non-A, non-B and non-C hepatitis virus. Compared with that of non-HASAA, the abnormality of T cell immunity of HAAA was more severe, with a higher frequency of early infection and a higher mortality rate.

Adolescent↗