SIMCA(self independent modeling of class analogy) is a classical class modeling method for chemical) pattern recognition. Although widely used, SIMCA suffers difficulties in selecting a proper number of principal components and determining the decision region. A new class modeling technique based on partial least squares regression, partial least squares class model(PLSCM) is proposed, where the number of latent variables) and decision region can be readily estimated by the routine methods in multivariate calibration, e.g. Monte Carlo cross validation. PLSCM is successfully applied to identify trueborn bezoar samples from artificial and adulterated bezoar samples based on infrared spectra measured in the range of 4000-9000 cm~(-1). It is demonstrated that PLSCM outperforms SIMCA in terms of both maneuverability and identification accuracy. For the raw spectra, both the training and prediction accuracy of PLSCM are 100%. For the standard normal variate-processed data, the training and prediction accuracy of PLSCM is 99% and 100%, respectively.

Objective:To find small molecular leads for inhibition on early stage of HIV infection by identification and characterization of the HIV-1 gp41 C-helix mimotopes.Methods:For identification of the gp41 C-helix mimotopes,C7C phage display peptide library was biopanning by using a synthetic peptide N36 which was derived from the gp41 N-helix as target.After three rounds of screening,positive phage clones were identified by ELISA and sequenced.Results:16 of 26 phage clones were identified to bind with peptide N36,and 10 of them were sequenced.Every clone of ten clones contains at least two hydrophobic residues,which may dock into the hydrophobic pocket in the gp41 N-helix domain.9 of the 10 clones have a conservative sequence WW,which may mimic the W628 and W631 in C-helix to interact with the hydrophobic residues in the gp41 pocket.One clone expressing the conservative sequence named clone No.8(CYWWHRLHC) was selected for characterization.The binding between the clone No.8 and N36 was blocked by free peptide N36.And the binding between clone No.8 and peptide N36 was inhibited by peptide C34(IC 50=12.5 ?g/ml).Conclusion:The short circular peptides displayed on phages containing WW residues may mimic the conformational epitope of the HIV-1 gp41 C-helix to interact with the N-helix.This information may be useful for design of HIV-1 fusion inhibitors.

Objective:To screen and characterize the common epitopes recognized by monoclonal antibody 3A8,which binds several kinds of Gram negative bacteria,which were recognized by monoclonol antibody 3A8 agaisnt different strains of LPS.Methods:Phage clones binding to 3A8 were screened from C7C phage displayed peptide library,the attached phage clones were eluted by LPS2630(O111:B4).After 3 rounds of panning,the positive phage clones were identified by ELISA,and the amino acid sequences of these positive clones were deduced from DNA sequences.In order to predict how these peptide mimics interaction with 3A8,peptides(A2 and A5) based on conserved sequences of positive clones were synthesized and conjugated with KLH for further study.The binding of A2-KLH and A5-KLH to 3A8 were identified by ELISA.Results:15 of 33 phage clones were identified as positive clones and shown specific binding with 3A8.LPS2630 potently inhibited the binding of phage clone to 3A8.In analysis of the amino acid sequence,there were seven kinds of sequences containing highly hydrophilic residues,and Ser Pro Pro/Pro X Pro was the conserved sequence.The peptides A2 and A5 could bind to 3A8 specially.Conclusion:The conserved sequences containing Ser Pro Pro/Pro X Pro are obtained,which are recognized by mAb 3A8 against broad spectrum Gram negative bacteria and several strain LPS.The synthetic peptides based on the conserved sequence can bind to 3A8,indicating that the peptides can mimic a common epitope of Gram negative bacteria,which be expected as candidate epitope for vaccinization.

AIM To modify and improve a screening assay so that it becomes more convenient, economic and adaptable in China for high throughput screening of HIV fusion inhibitors targeting gp41. METHODS The original screening method reported by Jiang et al (J Virol. Methods 1999;80:85 96) was modified by: ① using a conformation specific monoclonal antibody to replace a polyclonal antibody for coating plates; ②simplifying the procedures; ③using parts of the reagents produced in China. RESULTS The modified screening assay is simpler, more convenient, and more economic than the original assay, but its sensitivity is comparable to and specificity is a little better than the original method. CONCLUSIONS The modified screening assay is more convenient and economic and can be used in China for high throughput screening of HIV fusion inhibitors from complex sample, such as phage display peptide libraries, microorganism fermentation liquids, herbs and other natural products.

Objective To evaluate the method of establishment of a minipig model of ischemic heart failure(HF) with acute myocardial infarction(AMI) by coronary balloon occlusion and coadministration of injecting of microthrombi and plastic microspheres.Methods A total of eighteen minipigs were selected.After coronary angiography,angioplasty balloons were placed in the mid-distal of left anterior descending(LAD).The balloon was inflated intermittently to occlude the LAD 3 times and then to occlude it continuously for 120 minutes.After the balloon was taken out,4F Judkins-type angiogrphic catheter was superelectively engaged in LAD and 3 mL intermixture of mierothrombi and plastic microspheres were injected at 10 minites interval until TIMI myocardial perfusion was grade<2 and left ventfieular end-diastolic pressure was maintained from 15 to 18 mmHg.Electrocardiogram(ECG),hemodynamic perameters,ultrasonic cardiogram,cTnI and CK-MB were measured.Myocardial infarction area was evaluated by histopathology.Results Fourteen days later,fifteen minipigs survived and fourteen satisfied the criteria(pulmonary capillary wedge pressure.PCWP>18 mmHg and eardio output (CO) decreased beyond 30% ). The changes of ECG, hemodynamic perameters, CKMB, cTnI and cardiac pathologic examination were in accordance with AMI. Conclusion A stable experimental method of establishment of minipig model of ischemic heart failure (HF) with acute myocardial infarction (AMI) by coronary balloon occlusion and coadministration of injecting of microthrombi and plastic mierospheres is succeded. This method has advantages such as closed chest, higher success rate and stability compared with the drug induced, taehycardia-pacing induced, coronary artery ligation induced or microsphere injection alone methods.

In recent 10 years, using radiofrequency catheter ablation, our medical center has treated 4865 cases of paroxysmal supraventricular tachycardia (PSVT). To improve clinical practice, a retrospective analysis of this group was made. In this group, 2092 cases were atrioventricular reentry tachycardia (AVRT), including 1415 left accesory pathway and 677 right accesory pathway, and 2773 cases were atrioventricular nodal reentry tachycardia (AVNRT). The total success rate of radiofrequency treatment is 99.71%; the recurrence rate after half a year 1.73%; the total complication rate 1.25%. In conclusion, radiofrequency ablation is a safe and effective treatment for tachycardia with high rate of success and low rate of complication.
Adult ; Catheter Ablation ; Female ; Humans ; Male ; Retrospective Studies ; Tachycardia, Paroxysmal ; surgery ; Tachycardia, Supraventricular ; surgery ; Young Adult

OBJECTIVETo assess the prognostic factors associated with the sudden idiopathic sensorineural hearing loss, to predict the prognosis of patient with idiopathic sensorineural hearing loss precisely.

METHODSEight hundreds and eighty two patients with idiopathic sudden sensorineural hearing loss were retrospectively reviewed during January 2006 to March 2007. Patients whose initial hearing threshold < or =40 dB were excluded. The patients with initial hearing threshold >40 dB were recruited, which was divided into six subgroups based on the patterns of audiogram: downgrade audiogram subgroup, upgrade audiogram subgroup, flat audiogram subgroup, concave audiogram subgroup, profound audiogram subgroup and total deafness subgroup.

RESULTSRegarding to the relationship between the time point for initial intervention and the prognosis, better prognosis was obtained in patients whose initial intervention was within 3 days of the disease, good prognosis was achieved within 1 or 2 weeks of the disease, poor prognosis was noted beyond 2 weeks of this disease. Furthermore, comparison with the initial intervention within 3 week, 1 month and 1 month later, the prognosis among them was not statistical different. 97.7% hearing recovery was achieved in the concave subgroup with the initial hearing threshold >40 dB group. Comparison with the other subgroup (except total deafness subgroup), the cure rate and recovery rate was 23.8% and 57.9% respectively in the profound subgroup. Poor prognosis was demonstrated in the total deafness subgroup and inefficacy rate was 67.4% in the total deafness subgroup. Comparison with patients without companying complications, the prognosis of patients with companying complications such as diabetes or high blood pressure has negative impact in hearing recovery. The age was correlated with the prognosis, elder had poor prognosis, patients more than 50 years old present with worse hearing than that less than 50 years old (H = 7.851, P = 0.0051).

CONCLUSIONSThe initial intervention beyond 2 weeks had negative impact on the prognosis. The initial audiogram patterns and hearing threshold were both significant factors on the prognosis of idiopathic sudden sensorineural hearing loss. In addition, old patient had poor prognosis. The companying complications such as high blood pressure and diabetes had negative impact on the prognosis of idiopathic sudden hearing sensorineural loss.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Audiometry ; Auditory Threshold ; Child ; Female ; Hearing Loss, Sensorineural ; complications ; diagnosis ; physiopathology ; Hearing Loss, Sudden ; complications ; diagnosis ; physiopathology ; Humans ; Male ; Middle Aged ; Prognosis ; Retrospective Studies ; Risk Factors ; Young Adult

AIMTo approach the effects of multi-site synchronous ventricular pacing on myocardial mechanics and cardiac work.

METHODSFive modes of multi-site synchronous ventricular pacing were randomly performed in 12 dogs with anesthetized, opened chest and artificial-ventilation. Some parameters were measured simultaneously including: the peak of left ventricular pressure rise and fall (+/- dp/ dt(max)), the time constant of left ventricular relaxation(tau), the muscle tensile force in left/right ventricular wall (V-tensile force, V-TF), SV, LVSW and RVSW.

RESULTSThe myocardial systolic mechanical parameters: +dp/dt(max) and LV-TF of cHisB-LVPL and RVA-LVPL pacing by biventricular pacing modes were increased than that of cHisB-RVA pacing in right ventricular bifocal pacing mode. +dp/dt(max) in above two groups of biventricular pacing was increased than that in cHisB-RVA pacing. Tau value of cHisB-LVPL and RVA-LVPL pacing modes were shorted than that of cHisB-RVA pacing. The above parameters of cHisB-RVA-LVPL and cHisB-RVA-LVA biventricular trifocal pacing were superior to that of cHisB-LVPL and RVA-LVPL biventricular pacing. The +dp/dt(max), LV-TF and RV-TF of cHisB-RVA-LVPL pacing were increased as compared with that of cHisB-RVA-LVA pacing (P > 0.05). The -dp/dt(max) in cHisB-RVA-LVPL pacing were increased by 6.0% and tau value was shorted by 3.7% compared with those in cHisB-RVA-LVA pacing (P > 0.05). SV, LVSW and RVSW of cHisB-LVPL and RVA-LVPL biventricular pacing were increased than those of cHisB-RVA bifocal pacing. The above parameters of cHisB-RVA-LVPL pacing were increased than that of cHisB-RVA-LVA and cHisB-LVPL pacing.

CONCLUSIONIt was explained that the cHisB-RVA-LVPL biventricular trifocal sites synchronous pacing mode would increase the velocity of ejection and filling during myocardial contraction and relaxation and enhance cardiac work by maintaining normal VSS.

Animals ; Cardiac Pacing, Artificial ; methods ; Dogs ; Female ; Heart ; physiology ; Heart Ventricles ; Male ; Myocardium

Action Potentials ; Animals ; Electromyography ; Environmental Exposure ; Hypothermia ; Rats ; Rats, Wistar ; Seawater ; Thigh ; physiology ; physiopathology

OBJECTIVETo investigate the compositions of Th1/Th2/Th3 cells in chronic hepatitis B virus (HBV)-infected individuals by determining the expression of interleukin-4 (IL-4), inetrferon-gamma (IFN-gamma), and transform growth factor-beta (TGF-beta) in single CD4(+) T cells isolated from peripheral blood mononuclear cells (PBMCs) and the role of polarized Th cell populations in chronic HBV-infection was discussed.

METHODSPBMCs from chronically infected HBV individuals were isolated, stimulated by PMA/Ionomycin/Monensin, and IL-4, IFN-gamma and TGF-beta production by CD4(+) T cells was determined by using fluorescence activated cell sorter (FACS) analysis.

RESULTSThe percentage of IFN-gamma-producing T cells, IL-4-producing T cells and TGF-beta-producing T cells ranged from 2.3% - 18.6%, 1.1% - 8.7% and 0.7% - 7.1% respectively in CD4(+) T cells from non-infected individuals. Most of CD4(+) T cells from PBMCs in chronically infected HBV individuals were Th0 cells. The proportion of Th1 cells increased significantly with hepatic inflammatory activity, and in the active period of chronic hepatitis B infection were higher than those in the non-active period (P < 0.05). Th2 cell percentage in CD4(+) T cells from HBV-infected individuals did not differ significantly (P > 0.05), but were higher than that from controls (P < 0.05). Th3 cell percentage in CD4(+) T cells from asymptomatic carrier (AsC) group was higher than that in the chronic hepatitis B (CHB) and control groups (P < 0.05).

CONCLUSIONSTh1 phenotype cytokines were positively correlated with hepatic inflammatory activity in chronic hepatitis B and Th2 cells may be associated with the persistence of HBV infection. Th3 cells cooperating with Th2 cells can negatively regulate immune responses and may be associated with the immune tolerant state of chronic HBV infection.

CD4-Positive T-Lymphocytes ; immunology ; Hepatitis B, Chronic ; immunology ; metabolism ; pathology ; Humans ; Interferon-gamma ; biosynthesis ; Interleukin-4 ; biosynthesis ; T-Lymphocytes, Helper-Inducer ; immunology ; Th1 Cells ; immunology ; Th2 Cells ; immunology ; Transforming Growth Factor beta ; biosynthesis