This paper discusses the relationship between stimulating pulse width and the threshold of electrically evoked compound action potential (ECAP). Firstly, the rheobase and chronaxy from strength-duration curve of nerve fiber was computed using the shepherd's experiment results. Secondly, based on the relationship between ECAP and the action potential of nerve fiber, a mathematical expression to describe the relationship between stimulating pulse width and ECAP threshold was proposed. Thirdly, the parameters were obtained and the feasibility was proved to the expression with the results of experiment using guinea pigs. Research result showed that with ECAP compared to the action potential of nerve fiber, their threshold function relationship with stimulating pulse width was similar, and rheobase from the former was an order smaller in the magnitude than the latter, but the chronaxy was close to each other. These findings may provide meaningful guidance to clinical ECAP measurement and studying speech processing strategies of cochlear implant.
Action Potentials ; Animals ; Auditory Threshold ; Cochlear Implantation ; Cochlear Implants ; Electricity ; Evoked Potentials ; Guinea Pigs ; Neural Conduction

The purpose of this article was to investigate the application of Google Earth (GE)in the Three Dimensional Visualization(TDV)of the warnings signaled by early warning system of infectious disease.As an example.the prospective space-time scan statistics was used by mimicking daily prospective analyses of bacillary dysentery data from Shanghai municipality,Zhejiang province and Jiangsu province in 2005.Then one of the warnings was picked to illustrate the visualization of GE.GE could vividly display the results in three dimensions containing the complex information including date,areas,observed numbers,expected numbers ere.GE seemed a useful tool for infectious disease surveillance and had potential important values in reflecting the emergency response situation.The development of integrated system which consisted of GE,the infectious disease reporting system and cluster detection methods need to be emphasized for further research.

To investigate the chemical constituents of the whole plants of Bidens bipinnata, the separation and purification of constituents were performed by chromatography on macroporous resin, silica gel, MCI and Sephadex LH-20. Their structures were elucidated by spectroscopic data as quercetin (1), quercetin-3-0-alpha-L-rhamnoside (2), keampferol-3-O-beta-D-glucopyranoside (3), keampferol-3-O-alpha-L-rhamnoside (4), 3', 5-dyhydroxy-3, 6, 4'-trimethoxyl -7-O-beta-D-glucopyranoside flavonoid (5), 7, 8, 3', 4'-tetraflavanone(6), (2S)- and (2R)-isookanin-7-O-beta-D- glucopyranoside (7a/7b), (2S)- and (2R)-3'-methoxy-isookanin-8-O-beta-D-glucopyranoside (8a/8b), 6, 7, 3', 4'-tetrahydroxyaurone(9), maritimetin (10), esculetin (11), 3-O-caffeoyl-2-methyl-d-erythrono-1, 4-lactone (12), (7S, 8R) balanophonin-4-O-beta-D-glucopyranoside (13), eugenyl-O-beta-apiofuranosyl-( 1"-6') -O-beta-glucopyranoside (14), and (+)-syringaresinol-4'-O-beta-D-glucopyranoside (15). Compounds 8, 13, 14, and 15 were isolated from this genus for the first time. Compounds 1 and 6 were potent inhibitors against HSC-T6 cells in vitro and compounds 1, 2, 6, and 7 were capable of decreasing the inflammatory cytokine production of macrophage cells in vitro.
Bidens ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Molecular Structure ; Spectrometry, Mass, Electrospray Ionization

OBJECTIVETo investigate the application of prospective space-time scan statistic in the early stage of detecting infectious disease outbreaks.

METHODSThe prospective space-time scan statistic was tested by mimicking daily prospective analyses of bacillary dysentery data of Chengdu city in 2005 (3212 cases in 102 towns and villages). And the results were compared with that of purely temporal scan statistic.

RESULTSThe prospective space-time scan statistic could give specific messages both in spatial and temporal. The results of June indicated that the prospective space-time scan statistic could timely detect the outbreaks that started from the local site, and the early warning message was powerful (P = 0.007). When the merely temporal scan statistic for detecting the outbreak was sent two days later, and the signal was less powerful (P = 0.039).

CONCLUSIONThe prospective space-time scan statistic could make full use of the spatial and temporal information in infectious disease data and could timely and effectively detect the outbreaks that start from the local sites. The prospective space-time scan statistic could be an important tool for local and national CDC to set up early detection surveillance systems.

China ; Communicable Disease Control ; methods ; Communicable Diseases ; epidemiology ; Humans ; Models, Statistical ; Population Surveillance ; methods ; Prospective Studies

BACKGROUNDTo avoid the irritation of tendons and soft tissues as well as hardware-related problems, we designed an intramedullary fixation with bioabsorbable rods for the treatment of the metacarpal shaft fractures.

METHODSFive patients with nine shaft fractures of the fourth and fifth metacarpi were treated with intramedullary absorbable implants and followed up with an average of 4.2 months postoperatively.

RESULTSAt final follow-up, all patients achieved fracture union with no signs of inflammatory or subcutaneous effusion. There was no shortening, angulatory, or rotatory deformity. There was almost full active extension range of motion (ROM) of the metacarpophalangeal joints while the active flexion ROM of these joints was 80.7 ± 9.6°. Compared with the contralateral hand, the grip strength of the injured hand was 94.0 ± 9.6%. X-rays showed that the arch of the second to fifth metacarpal heads was smooth. There were no intramedullary lytic changes and soft tissue swellings.

CONCLUSIONThe intramedullary absorbable implants are a safe, simple, and practical treatment for fourth and fifth metacarpal fractures with good early clinical outcomes and no significant complications.

Absorbable Implants ; Adolescent ; Adult ; Fracture Fixation, Intramedullary ; methods ; Fractures, Bone ; surgery ; Humans ; Internal Fixators ; Male ; Metacarpal Bones ; injuries ; surgery ; Range of Motion, Articular ; physiology ; Treatment Outcome ; Young Adult

OBJECTIVETo investigate the apoptosis-promoting effect of PDCD5 on human prostate cancer cells PC-3M-1E8.

METHODSPCI-neo and PCI-neo-PDCD5 were transfected into PC-3M-1E8 cells by Lipofectamine 2000, the viability of the cells was analyzed by MTT assay 16 hours after removal of the serum, and the apoptosis was determined by in situ end-labeling and electron microscopy.

RESULTSThe viability and growing speed of the transfected cells were significantly decreased and their apoptotic indexes significantly increased as compared with the control group (P < 0.001).

CONCLUSIONPDCD5 may significantly inhibit the in vitro growth and promote the apoptosis of human prostate cancer cells PC-3M-1E8.

Apoptosis ; genetics ; physiology ; Apoptosis Regulatory Proteins ; genetics ; physiology ; Cell Line, Tumor ; Humans ; In Situ Nick-End Labeling ; Lipids ; chemistry ; Male ; Neoplasm Proteins ; genetics ; physiology ; Plasmids ; chemistry ; genetics ; Prostatic Neoplasms ; genetics ; pathology ; Reverse Transcriptase Polymerase Chain Reaction ; Transfection ; methods

OBJECTIVETo explore the hematopoietic pathophysiology of myelodysplastic syndrome (MDS) at stem/progenitor cell level by analyzing the gene expression profiles associated with hematopoiesis.

METHODSThe differentially expressed genes which were involved in the hematopoiesis were screened by microarray using CD34(+) cells from MDS patients firstly. RQ-PCR was then applied to validate the screened genes using CD34(+) cells from MDS-RA patients who had normal karyotype. The linkages with hematopoiesis among these validated genes were analyzed.

RESULTSAmong the differentially expressed genes in CD34(+) cells of MDS-RA patients, Rap1GAP was up-regulated significantly (P < 0.01). Cadherins, which can interplay with Rap1, including N-cadherin and E-cadherin, were down-regulated significantly (P < 0.01). β-catenin, a downstream effector of cadherins, was highly expressed in MDS-RA patients (P < 0.01). c-myc binding protein was down-regulated (P < 0.01), and c-myc promoter binding protein was up-regulated (P < 0.01). Rac1, Rac2 and Cdc42, which belong to RhoGTPases family and are associated with the cell morphology and hematopoiesis, were all expressed highly in MDS-RA patients (P < 0.01).

CONCLUSIONThe abnormal expression of cadherin, β-catenin and c-myc associated genes were closely related to the dysplastic hematopoiesis of MDS. The down regulation of cadherin was associated with the positive feedback mechanism between Rap1 and cadherin. The aberrant expression of Rac1, Rac2 and Cdc42 may contribute to the morphological dysplasia of MDS.

Cadherins ; genetics ; metabolism ; Gene Expression ; Gene Expression Profiling ; Genes, myc ; Humans ; Myelodysplastic Syndromes ; genetics ; metabolism ; beta Catenin ; genetics ; rap1 GTP-Binding Proteins ; genetics ; metabolism

Objective To investigate the prevalence and incidence of Keshan disease (KD) and the selenium concentration of food and hair in residents of Yongjin Village, Fuyu County, Heilongjiang Province, national monitoring site, in 2007. Methods According to the Standard of Keshan Disease Surveillance and the Standard of Diagnosis of Keshan Disease(GB 17021-1997), the residents living in the monitoring site were surveyed by clinical examination and electrocardiography. For individuals whose hearts showed abnormalities, a chest X-ray photograph was taken. The selenium concentrations of the residents' food (flour) and hair were assayed by flowing injection hydride generation atomic fluoremetric method(FI-HG-AFM). Results Nineteen KD patients were found from 282 residents in 2007 KD surveillance. The prevalence of KD, latent KD and chronic KD were 6.7%(19/282), 2.8%(8/282) and 3.9%(11/282), respectively. Five of the 8 latent KD cases were newly found. In addition, there were 5 the suspected KD cases, including 2 suspected chronic KD cases. No acute KD or sub-acute KD patients were found in Yongjin Village at this monitoring site this year. The average selenium concentration of children hair and residents food were (0.3197±0.0586)mg/kg and (0.0210±0.0062)mg/kg, respectively. Conclusions New cases of KD continued to emerge, indicating that etiological factors still exist. Therefore, the emphasis of monitoring KD in furore is founding the consummate report of infectious disease system and training the personnel to increase the reliability of monitoring.

BACKGROUND AND OBJECTIVEPrecursor T lymphoblastic lymphoma (T-LBL) is a highly aggressive lymphoma. Myeloid antigen expression was found in some of the patients, and its clinical significance is worth studying. This study was to compare the clinical features, short-term efficacy and survival of T-LBL patients with or without myeloid antigen expression so as to evaluate its prognostic significance.

METHODSForty-five T-LBL patients, with a median age of 14 years, were treated at Sun Yet-sen University Cancer Center between January 2000 and July 2008. These patients were divided into myeloid antigen-positive group (My(+) group) and myeloid antigen-negative group (My(-) group) based on the flow cytometric (FCM) analysis in bone marrow or pleural fluid. Myeloid antigen expression and its correlation with the short-term efficacy and overall survival were assessed in the two groups.

RESULTSThere were 18 patients (40.0%) in the My(+) group and 27 (60.0%) in the My(-) group. The myeloid antigen expression was negatively correlated with the initial level of lactate dehydrogenase (LDH), but not with other clinical features. The remission rate was lower in the My(+) group than in the My(-) group (38.8% vs. 70.3%, P = 0.028). The 2-year overall survival rate was lower in the My(+) group than in the My(-) group (51.9% vs. 78.7%, P = 0.036). By age subgroup analysis, there were no differences in response and survival rate among children and adolescents with or without myeloid antigen expression. But the remission rate and the 2-year overall survival rate were significantly lower in adult patients with myeloid antigen expression than in patients without it. Univariate and multivariate analysis demonstrated that age and myeloid antigen expression were adverse prognostic factors.

CONCLUSIONMyeloid antigen expression is a predictor of a poor response to chemotherapy, and adverse prognostic factor in adult T-LBL, but not in children with T-LBL.

Adolescent ; Adult ; Age Factors ; Aged ; Antigens, CD7 ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Asparaginase ; therapeutic use ; Child ; Cyclin D3 ; metabolism ; Cyclophosphamide ; therapeutic use ; Cytarabine ; therapeutic use ; Daunorubicin ; therapeutic use ; Doxorubicin ; therapeutic use ; Etoposide ; therapeutic use ; Female ; Follow-Up Studies ; Humans ; Male ; Mercaptopurine ; therapeutic use ; Methotrexate ; therapeutic use ; Middle Aged ; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; immunology ; Prednisone ; therapeutic use ; Proportional Hazards Models ; Remission Induction ; Survival Rate ; Transcription Factors ; metabolism ; Vincristine ; therapeutic use ; Young Adult

OBJECTIVETo understand the HBV infection rate of peripheral blood mononuclear cells (PBMCs) from fetuses of HBsAg positive mothers, associated risk factors and to explore the clinical significance of detecting HBV infected PBMCs.

METHODSSixty eight pregnant women who were delivered at the First Hospital of Xi'an Jiaotong University, China from August 1995 to February 1997, and their newborns were studied. They were divided into two groups according to their status of HBV serological markers. The study group included 50 cases who were serum HBsAg positive and 18 cases without any HBV serum markers served as control group. All these cases had no symptoms of hepatitis, high risk premature labor, premature delivery and hypertensive disorder complicating pregnancy. Age and gestational age were matched in two groups. Blood samples (5 mL) were taken from the peripheral vein of pregnant women before delivery and from newborns within 24 h after birth, before inoculation of HBV vaccine (HBVac) and injection of hepatitis B immunoglobulin (HBIG). PBMCs were isolated. The sera and PBMCs were stored at -80 degrees C. HBV-DNA in serum and PBMCs were detected with nested polymerase chain reaction (n-PCR). Two pairs of oligonucleotide primers, the outer primer pair for first PCR and inner primer pair for second PCR, designed according to region S of HBV genome were synthesized by Shanghai Cell Biology Institute of Chinese Academy of Science.

RESULTSThe detection rate of HBV-DNA in serum and PBMCs from HBsAg positive pregnant women was 60.0% (30/50) and 40.0% (20/50), respectively. The detection rate of HBV-DNA in serum and PBMCs from newborns of HBsAg positive pregnant women was 46.0% (23/50) and 30.0% (15/50), respectively. Ten newborns were HBV-DNA positive in serum only, 2 were positive in PBMCs only and 13 were positive in both serum and PBMCs. In the control group, HBV-DNA was not detected in PBMC nor in serum. The positive rate of HBV-DNA in PBMCs of newborns was significantly higher in the group of mothers who were HBV-DNA or HBeAg positive in serum (P < 0.05, P < 0.01); the positive rate was significantly higher in the group of mothers who were HBV-DNA positive in both serum and PBMC than that in the group of mothers who were serum HBV-DNA positive only (P < 0.01); and it was markedly higher in the group of mothers who were PBMC HBV-DNA positive than that in group of mothers who were HBV-DNA negative in PBMCs (P < 0.01). The positive rate of HBV-DNA in PBMCs of newborns was significantly higher in the group of newborns who were HBV-DNA positive in serum than that in the group of newborns who were HBV-DNA negative in serum (P < 0.05).

CONCLUSIONSThe positive rate of HBV-DNA in PBMCs from newborns of HBsAg positive pregnant women was 30.0% (15/30). It was related to HBV viremia level and HBV-DNA status in PBMCs of mothers and newborns. Detection of HBV-DNA in PBMCs may be an important supplementary method to determine intrauterine HBV infection, and can predict the response to HBV vaccine.

Adult ; Case-Control Studies ; DNA, Viral ; blood ; Female ; Hepatitis B Vaccines ; administration & dosage ; Hepatitis B virus ; immunology ; isolation & purification ; Humans ; Immunoglobulins ; administration & dosage ; Infant, Newborn ; blood ; Infectious Disease Transmission, Vertical ; prevention & control ; Injections, Intramuscular ; Leukocytes, Mononuclear ; virology ; Male ; Mothers ; Polymerase Chain Reaction ; Pregnancy ; blood ; Risk Factors ; Time Factors ; Treatment Outcome