This paper proposes a method based on quaternion for characterization a helix of proteins. The method defines the parameter called Quaternion Helix Axis Spherical Distance (QHASD) on the basis of mapping protein Cα frames' helical axis onto a unit sphere, and uses QHASD to characterize the a helix of the protein secondary structure. Application of this method has been verified based on the PDBselect database, with an a helix characterization accuracy of 91.7%. This method possesses significant advantages of high detection accuracy, low computation and clear geometric significance.
Algorithms ; Databases, Protein ; Models, Molecular ; Protein Structure, Secondary ; Proteins ; chemistry

Oncosis is a special kind of non-apoptotic cell death mode. It is characterized by cellular swelling, organelle swelling, blebbingand increased membrane permeability. More and more attentions pay to the research of this field in recent years. The review discuss the recent advances of oncosis on pathological change, molecular mechanisms and detection approaches.

OBJECTIVE:To observe the efficacy and safety of azithromycin sequential therapy in the treatment of mycoplasma pneumonia in children. METHODS:67 children with mycoplasma pneumonia were randomly divided into control group(34 cases) and observation group (33 cases). All children received conventional treatment,such as fever,cough,supplemented by nutrition support;based on it,control group received 10 mg/kg Azithromycin for injection,adding into 5% Glucose injection by intrave-nous drip in 200 ml,once a day;observation group received azithromycin(the same dosage with control group)after intravenous drip 5 d,switched to 10 mg/(kg·d)Azithromycin dry suspension,orally,then stopped 4 d after continuous 3 d. The treatment course was 7-10 d. Clinical efficacy,disappearance time of fever,cough and lung rales,and lung indexes before and after treat-ment,and the incidence of adverse reactions in 2 groups were observed. RESULTS:There were no significant differences in the to-tal effective rate,disappearance time of fever,cough and lung rales in 2 groups(P>0.05). After treatment,the lung function in-dexes were significantly higher than before,the differences were statistically significant(P<0.01),but there was no significant dif-ference between 2 groups (P>0.05). The incidence of adverse reactions in observation group was significantly lower than control group,the difference was statistically significant (P<0.05). CONCLUSIONS:Based on conventional treatment,azithromycin se-quential therapy shows similar efficacy to without sequential therapy in the treatment of mycoplasma pneumonia in children,but with better safety.

Objective: To observe the clinical efficacy of warm needling moxibustion plus Mulligan dynamic joint mobilization for cervical radiculopathy. Methods: A total of 60 cases with cervical radiculopathy were randomly divided into group A, group B and group C by random digital table, 20 cases in each group. The patients in three groups were treated with similar warm needling moxibustion. Group A only received warm needling moxibustion; group B was treated with warm needling moxibustion plus Mulligan dynamic joint mobilization; group C was treated with warm needling moxibustion plus cervical traction. Before the treatment and after 12 sessions of treatment, the patients in the three groups were assessed for score of pain and range of motion (ROM). Results: By 12 sessions of the treatments, the scores of pain were obviously decreased in the three groups, with statistical significances (all P<0.05), and the pain scores of group B and group C were significantly different from the score of group A (both P<0.05). ROM of the neck was increased than before the treatment in the three groups, with statistical significances (all P<0.05), and the ROM of the neck of group B was significantly different from those of group A and group C (both P<0.05). Conclusion: Warm needling moxibustion plus Mulligan dynamic joint mobilization can effectively improve the neck ROM and relieve pain in patients with cervical radiculopathy.

Objective To investigate the clinical efficacy of Sanqi Decoction in the treatment of early diabetic nephropathy (Diabetic, Nephropathy, DN) and its influence on the metabolism of lipid and glucose and renal function. Methods 96 patients with DN in our hospital were randomly divided into two groups. 48 cases in control group were treated with Enalapril, and 48 cases in observation group were treated with Sanqi decoction. Results The total effective rate of the observation group was 95.65%, which was significantly higher than that of the control group (81.25%) (P<0.05). Lipid, glucose metabolism and renal function improvement were better than those in the control group (P<0.05). Conclusion Sanqi Decoction is effective in the treatment of early DN, it can effectively improve the metabolism of lipid and sugar, reduce the excretion rate of urinary albumin, and have the effect of renal protection.

Objective To investigate the impact of stable expression of perlecan shRNA lentiviral particles on proliferation of NIH3T3 cells. Methods Mouse fibroblasts were cultured.Lentiviral particles-green fluorescent protein (LV-GFP) was used to transfect the cultured NIH3T3 cells with multiplicity of infection (MOI) of 10,30 and 50.The GFP expression was observed with fluorescence microscopy after transfection for one week to estimate the proper MOI and the time of GFP expression needed.The transfection efficiency of LV-GFP with the proper MOI by fluorescence-activated cell sorting was detected.The stably transfected cell lines were developed by puromycin screening for more than 2 weeks.The third generation HFF in good condition was randomly divided into 3 groups:GFP group,shRNA group and control group.RT-PCR,Western blot and MTT assays were used to detect the expressions of perlecan mRNA and protein and cell proliferation in the 3 groups. Results Perlecan mRNA and protein showed high expressions in the control and GFP groups but low expressions in the shRNA group,with significant differences respectively between the shRNA group and the other 2 groups ( P ＜ 0.05).There was no significant difference between the 3 groups in the optical density at the first 2 days ( P ＞ 0.05).On 3 to 6 days the cells in the control and GFP groups grew normally while the cells in the shRNA group proliferated in a weak manner.the transfected cells in the shRNA group showed a significantly reduced proliferation rate compared with the other 2 groups ( P ＜ 0.05 ). Conclusion The growth of NIH3T3 cells can be inhibited significantly by transfection with perlecan shRNA lentiviral particles.

Objective To investigate the corneal posterior surface topography characteristics of keratoconus at early stages applying the Pentacam anterior segment analysis system. Methods The present study included 43 eyes of 43 patients with keratoconus at the subclinical stage (group A), 40 eyes of 40 suspected keratoconus patients (group B), and 143 normal eyes of 143 controls (group C). Based on an examination of the Pentacam anterior segment analysis system of each subject, a series of data, including the posterior surface refractive power, the posterior surface elevation were collected. The differences among the three groups, the correlation among indices, and the area under the receiver operating characteristic (ROC) curves were analyzed. Results The mean values of the posterior surface maximum refractive power in 3 groups were -6.2 D, Q=0.5;-5.6 D, Q=0.3;and -5.5 D, Q=0.3, respectively. The mean values of the posterior surface maximum elevation were 23 μm, Q=14;11 μm, Q=8.5;and 7 μm, Q=6, respectively. The posterior surface maximum refractive power and maximum elevation among three groups were statistically different. The area under ROC (AUR) of posterior maximum refractive power and the AUR of posterior maximum elevation were greater than that of other indices in the diagnosis of early keratoconus. Conclusions Based on the results from the Pentacam anterior segment analysis system, the changes of the posterior surface refractive power and elevation are important characteristics of early keratoconus.

Objective To find out social support status and its influencing factors in left-home-kids in rural areas. Methods 893 left-home-kids and 335 non-left-home-kids were interviewed with the social support rating scale. Results The total score of social support of left-home-kids was obviously lower than that of non-left-home-kids; in the same way, the score of female was higher than male, the score of low age group was higher than high age group, the score of kids with father or mother as the custodian was higher than that of other custodian subjects; the score of children whose left-home duration was more than five years was higher than that of lower than one year. Conclusions The social support of left-home-kids was poorer than non-lefthome-kids. There is some difference in the social support in left-home-kids with different sex, age, custodian subject, left-home duration. Social support should be given to children with low social support.

Objective To observe the clinical effect of mesalazine combined with bifidobacterium in the treatment of ulcerative colitis and its effect on serum inflammatory cytokines.Methods 80 patients with ulcerative colitis were selected as the subjects.Auording to the digital table,the patients were randomly divided into observation group(40 cases) and control group(40 cases) by random number tables.The control group was treated with oral mesalazine only.The observation group was treated with bifidobacterium on the basis of the control group.Both two groups were treated for 8 weeks.Before and after treatment,the symptoms and microscopic manifestations were observed.The levels of CRP,TNF-α,IL-6 and IL-8 in venous blood were measured before and after treatment in the morning,and the clinical curative effect was evaluated.Results The proportions of diarrhea,abdominal pain and mucus bloody in the control group and the observation group were 20.0％ and 0.0％,22.5％ and 2.5％,20.0％ and 0.0％,respectively,which were significantly lower than those before treatment (x2 =46.036,72.381,26.467,52.379,22.175,48.000,all P ＜ 0.01).The improvement of diarrhea,abdominal pain and mucus bloody of the observation group was better than those of the control group(x2 =8.941,7.895,9.574,all P ＜ 0.05).The percentages of ulcers,erosions and bleeding points in the observation group and the control group were 22.5％ and 5.0％,32.5％and 10.0％,37.5％ and 7.5％,respectively,which were significantly lower than those before treatment (x2 =31.427,48.813,12.832,32.273,29.574,64.962,all P ＜ 0.01).The improvement of ulcer,erosive and bleeding in the observation group was better than those in the control group (x2 =5.084,6.74,10.853,all P ＜ 0.05).The levels of CRP,TNF-αt,IL-6 and IL-8 in the control group and observation group were (13.6 ± 3.6)mg/L and (7.8 ±1.2)mg/L,(28.4 ±9.6)ng/L and (15.6 ±7.1)ng/L,(141.3 ±21.4) ng/L and (90.5 ± 14.7) ng/L,(202.4 ±32.8) ng/L and (155.2 ± 25.4)ng/L,respectively,which were significantly lower than those before treatment (t =15.525 and 20.672,13.851 and 17.524,8.243 and 12.021,9.101 and 11.132,all P＜0.01),the CRP,TNF-α,IL-6 and IL-8 levels in the observation group were significantly lower than those in the control group (t =7.456,6.325,7.543,all P ＜ 0.01).The effective rate in the observation group was 97.5 ％ (39/40),which was significantly higher than that in the control group (77.5 ％,31/40),the difference was statistically significant (x2 =7.680,P ＜0.05).Conclusion Mesalazine combined with bifidobacterium has exact clinical effect in the treatment of ulcerative colitis,it is more effective in improving clinical symptoms and microscopic manifestations,and can reduce the level of serum proinflammatory cytokines.It is worthy to be used.

Objective To study the electrophysiologic characteristics of atrial-ventricular reentrant tachycardia(AVRT)characterized by paroxysmal occurrence that slow atrioventricular accessory pathway participatesin.Methods Twenty-one cases were chosen from patients receiring radiofrequency ablation therapy in Peking University People's Hospital from July in 1999 to January of 2005.The patients with slow atrioventricular accessory pathways diagnosed correctly were divided into two groups with paroxysmal tachycardia and permanent tachycardia in terms of the occurrent frequence of AVRT.The electrophysiologic features of AVRT of two groups were contrastively analyzed.Results Compared with the group of permanent AVRT,it was found that antidromic refractory period of slow atrioventricular accessory pathways was longer[(359?46)ms vs (318?31)ms,P