Background Sweep pattern visual evoked potential (SVEP) is an objective method of visual test.There is a clear correlation between SVEP acuity and subjective vision,but they are not identical.Recent studies showed that new regression method can improve the accuracy of SVEP acuity. Objective This trial was to investigate and compare the outcome between amplitude-spatial frequency (A-SP) regression method and amplitudelogVA (A-logVA) regression method in extrapolating the SVEP acuity.Methods SVEP was recorded in 113 eyes of 64 subjects using GT-2000 ( Guo Te,China) with the gratings of 10 different spatial frequency from 0.99 to 12.89 cpd as stimulus.The 1 13 eyes included cataract,glaucoma,corneal disease,optical neuropathy,retinal disease,ocular trauma,refractive error and normal eyes.The correlation were analyzed of SVEP acuity,decimal visual acuity and LogMAR visual acuity.The response were averaged and DFT on the monitor display.SVEP acuity was calculated by extrapolating 0 response amplitude.Results The correlation indices of decimal visual acuity curves obtained by the A-logVA function was 0.663,and that obtained by the A-SP function was 0.705.The positive correlation was seen between subjective decimal visual acuity and A-logVA decimal visual acuity (r =0.540,P＜ 0.01 ) and between subjective decimal acuity and decimal acuity calculated by the A-SP regression method (r=0.620,P＜0.01 ).SVEP decimal acuity calculated by the A-SP function regression method was significantly different from the that calculated by the A-logVA function regression method (Z =-8.688,P＜0.01 ).And the correlation indices of LogMAR visual acuity curves obtained by the A-logVA function was 0.733 and that obtained by the A-SP function was 0.715.The positive correlation was found between the subjective LogMAR acuity and that calculated by the A-SP regression method (r=0.700,P＜ 0.01 ) and between the subjective LogMAR acuity and LogMAR acuity calculated by the A-logVA regression method (r=0.710,P＜0.01 ).SVEP LogMAR acuity from A-SP function regression method was significantly different from the LogMAR acuity from A-logVA function regression method (Z=-8.748,P＜0.01 ).No significant differences of VA LogMAR were found in gender,eyes,type of disease and age(x2 =2.171,P=0.338;x2 =0.976,P=0.614;x2 =6.032,P=0.420;x2 =14.720,P=0.257 ).Conclusions SVEP can obtain the visual outcome in human.The amplitude-logVA function regression method is more accurate in extrapolating SVEP acuity.

Objective To evaluate the changes of the waveform of the photopic negative response in flash-electroretinogram, visual acuity and central retinal thickness in the treatment of intravitreal injections of bevacizumub. Design Retrospective self-comparative case series. Partidpants 8 subjects (9 eyes) with exudative age-related macular degeneration and 3 subjects (3eyes) with proliferative diabetic retinopathy. Method Evaluation protocol included examinations of the Early Treatment Diabetic Retinopathy study visual acu-ity, visual field, intraocular pressure, fundus fluorescein angiography, optical coherence tomography and flash-electroretinogram. Intravit-real injections of bevacizumab, 1.25 mg (0.05ml), were given under an operating microscope and aseptic conditions. All the subjects were followed-up one month later. Main outcome Measure The amplitudes of PhNR, visual acuity and central retinal thickness. Re-sult At 1 months, the mean amplitudes of PhNR and mean visual acuity in all cases had no obvious change (n=12, P>0.05).The central retinal thickness reduced obviously (n=12, P<0.05), but it was neither significantly correlated with PhNR (r=0.294, P=0.145) nor with visual acuity(r=-0.358, P=0.073). Conclusion The single intravitreal injection of bevacizumab is showed promising in absorption of in-traretinal edema and subretinal fluid in patients with exudative age-related macular degeneration and proliferative diabetic retinopathy, but the changes of visual function (including PhNR) might need further investigation. (Ophthalmol CHN, 2009, 18: 243-246)

BackgroundSweep pattern visual evoked potential(SPVEP) acuity,as an objective detective technique of visual function,can be used to measure visual acuity in children and uncooperative adults.Recent studies have shown that the amplitude-logarithm of the visual angle (A-LogVA) function regression method was more accurate than the amplitude-spatial frequency (A-SP)function regression method in evaluating SPVEP acuity.Objective This study was to explore the clinical use of SPVEP acuity in visual developing children and compare the evaluating the SPVEP acuity of children between A-SP function regression method and A-LogVA function regression method.Methods Twenty-six eyes of 26 asthenopic children with age range of 3-12 years and 31 age-matched normal children were enrolled in this study.SPVEP acuity was recorded with GT-2000 NV ( GUOTE MEDICAL APPARATUS LTD,China) using sinusoidally modulated horizontal gratings of 10 different spatial frequencies from 0.99 to 12.89 cpd as stimulus.The responses were averaged and displayed through discrete Fourier transformations (DFT) on the monitor display.SPVEP acuity was estimated by using both the SPVEP A-SP function regression method and the SPVEP A-LogVA function regression method.The LogMAR chart was used to acquire LogMAR visual acuity.ResultsIn the normal group,the correlation coefficient between LogMAR visual acuity and acuity calculated by the A-SP function regression method was 0.600 (P＜0.01).The correlation coefficient between LogMAR visual acuity and acuity calculated by the A-LogVA function regression method was 0.733 ( P＜0.01 ).The ANOVA of the LogMAR acuity and the SPVEP acuity calculated from the A-SP function regression method and A-LogVA function regression method were 113.173 (P＜0.01 ),which indicated that there were significant difference among all of subjects.The differences of the mean values of LogMAR visual acuity and the SPVEP acuity calculated from the A-SP function regression method and A-LogVA function regression method were respectively 0.40±0.02,0.26 ±0.02 and 0.14 ± 0.02.In the amblyopia group,the correlation coefficient between LogMAR visual acuity and acuity calculated by the A-SP function regression method was 0.134 (P =0.515 ).The correlation coefficient between LogMAR visual acuity and acuity calculated by the A-LogVA function regression method was 0.456 ( P＜0.05 ).The ANOVA of the LogMAR acuity and the SPVEP acuity calculated from the A-SP function regression method and A-LogVA function regression method were 3.433 (P＜0.05),indicating that there were significant difference among all of subjects.The differences of the mean values of LogMAR visual acuity and the SPVEP acuity calculated from the A-SP function regression method and A-LogVA function regression method were 0.07±0.05,0.12±0.05 and 0.05 ±0.01 respectively.Conclusions SPVEP can evaluate the visual acuity in children,although SPVEP acuity may overestimate or underestimate acuity in comparison with different LogMAR visual acuities.The amplitude-LogVA function regression method is more accurate in extrapolating SPVEP acuity.

Objective To analyze the risk factors for postoperative infection of patients with colorectal cancer,and to investigate the distribution of pathogenic bacteria and drug resistance.Methods A total of 300 patients with colorectal cancer who underwent operation were selected from June 2013 to June 2017 in the Central Hospital of Tongchuan Mining Bureau,and the patients were divided into the infection group and the non-infection group according to the postoperative infection.The clinical data were compared between the two groups,and the risk factors for postoperative infection in colorectal cancer patients were analyzed by logistic regression.The total automatic bacterial culture apparatus was used for bacterial culture,and the drug sensitivity test was carried out by Kirby-Bauer.Results Among the 300 colorectal cancer patients,there were 61 cases of incision infection (infection group) and 239 cases without incision infection (non-infection group) after operation,the postoperative infection rate was 20.33％ (61/300).There were significant differences in the operation method,red blood cell counts,the levels of albumin,prealbumin and hemoglobin between the two groups (P ＜ 0.05);but there was no significant difference in sex,age,body mass index,diabetes mellitus history,abdominal surgery history,smoking history,drinking history,operation time,intraoperative bleeding volume,hospitalization time,indwelling time of urethral catheter,white blood cells and C-reactive protein levels between the two groups(P ＞ 0.05).Multiple factor logistic regression analysis showed that the decrease of albumin and prealbumin level was the independent risk factor for postoperative infection in patients with colorectal cancer (P ＜0.05).A total of 52 strains of pathogenic bacteria were detected in 61 cases of colorectal cancer combined with postoperative infection,including 38 strains of gram negative bacteria (73.08％),10 strains of gram positive bacteria (19.23％) and 4 strains of fungi (7.69％).Escherichia coli,Klebsiella pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa had high drug resistance to ampicillin,cefaclor,ceftriaxone,ceftizoxime,cefepime,cefoperazone,ceftazidime and ofloxacin;but they had low drug resistance to piperacillin,imipenem and amikacin.Conclusion The incidence of postoperative infection in patients with colorectal cancer is higher,the decrease of albumin and prealbumin is the independent risk factor for postoperative infection in patients with colorectal cancer.Gram-negative bacteria are the main pathogens of postoperative infection in patients with colorectal cancer and have high resistance to common antibiotics.

Aortic Valve ; surgery ; Endocarditis ; surgery ; Humans

BACKGROUNDThe shape memory effect of nickel-titanium (NiTi) archwires is largely determined by the phase transition temperature. It is associated with a reversible transformation from martensite to austenite. The aim of this study was to characterize austenite, martensite and R phase temperatures as well as transition temperature ranges of the commonly used clinical NiTi orthodontic arch wires selected from several manufacturers.

METHODSDifferential scanning calorimetry (DSC) method was used to study the phase transformation temperatures and the phase transition processes of 9 commonly used clinical NiTi alloys (types: 0.40 mm (0.016 inch), 0.40 mm x 0.56 mm (0.016 inch x 0.022 inch)).

RESULTSThe austenite finish temperatures (Af) of 0.40 mm Smart, Ormco and 3M NiTi wires were lower than the room temperature, and no phase transformation was detected during oral temperature. Therefore, we predicted that these types of NiTi did not possess shape memory property. For 0.40 mm and 0.40 mm x 0.56 mm Youyan I NiTi wires, no phase transformation was detected during the scanning temperature range, suggesting that these two types of wires did not possess shape memory either. The Af of 0.40 mm x 0.56 mm Smart, L&H, Youyan II Ni-Ti wires were close to the oral temperature and presented as martensitic-austenitic structures at room temperature, suggesting the NiTi wires listed above have good shape memory effect. Although the 0.40 mm x 0.56 mm Damon CuNiTi wire showed martensitic-austenitic structures at oral temperature, its Af was much higher than the oral temperature. It means that transformation from martensite to austenite for this type of NiTi only finishes when oral temperature is above normal.

CONCLUSIONThe phase transformation temperatures and transformation behavior varied among different commonly used NiTi orthodontic arch wires, leading to variability in shape memory effect.

Calorimetry, Differential Scanning ; Dental Alloys ; chemistry ; Nickel ; chemistry ; Orthodontic Wires ; Temperature ; Titanium ; chemistry

OBJECTIVETo investigate the feasibility of utilizing self-designed score system for lower lumbar vertebral burst fractures to select surgical approach.

METHODSFrom January 2006 to December 2011, the clinical data of 56 patients with lower lumbar vertebra burst fractures who underwent surgical treatment were retrospectively analyzed. There were 42 males and 14 females with an average age of 43.1 years old (ranged, 19 to 65). Causes of injury included falling down (40 cases), traffic accidents (12 cases), and crashing injury by heavy objects(4 cases). Injury site was L3 in 37 cases, L4 in 16 cases, and L5 in 3 cases. According to the AO classification, 17 cases were type A3.1, 14 cases were type A3.2, 25 cases were type A3.3. According to Frankel grade of nerous function, 2 cases were grade B, 5 cases were grade C, 9 cases were grade D and 40 cases were grade E. Surgical methods and approaches were chosen based on the comprehensive evaluation of AO classification, condition of posterior column injury and spinal canal encroachment. Surgical methods and approaches included trans-vertebra fixation (15 cases), intra-vertebra pedicle screw fixation (21 cases), combination of anterior and posterior approaches (11 cases), one-stage posterior approaches (9 cases). Cobb angles, restorations of the affected vertebral anterior border height, and conditions of spinal canal encroachment were compared before and after surgery. Conditions of bone graft fusion and internal fixation (if bending, loosening or breakage existed) were observed. Spinal cord functions were assessed according to Frankel grade. Localized pain and working status of patients were also assessed at the last follow-up.

RESULTSNo incision infection was found and no spinal nerve symptoms improved in all of 56 patients. All patients were followed up for 12 to 60 months with a mean of 28.5 months, without internal fixation loosening or breakage. There was significant differences in Cobb angle, vertebral anterior border height and recovery of spinal canal encroachment between preoperative and postoperative instantly (P < 0.05), however, there was no significant difference between postoperative instantly and final follow-up (P > 0.05). Thirteen cases obtained fusion by trans-vertebra fixation, 20 cases obtained fusion by intra-vertebra fixation, and 20 cases were treated by the combination of anterior and posterior approaches or one-stage posterior approaches all of patients obtained fusion. Spinal nervous function recovered I to II grade, 1 case was grade C, 3 cases were grade D, 52 cases were grade E. Localized pain was assessed as P1 in 52 cases, P2 in 3 cases, and P3 in 1 case. Working status was classified into W1 in 12 cases, W2 in 39 cases, and W3 in 5 cases.

CONCLUSIONThe lower lumbar vertebra and thoracolumbar junction exhibit different injury characteristics due to variations in anatomy and biomechanics. A comprehensive score of the AO classification, posterior column injury and degree of spinal canal encroachment will guide the selection of surgical method and approach for the treatment of lower lumbar vertebra burst fractures.

Adult ; Aged ; Biomechanical Phenomena ; Female ; Follow-Up Studies ; Fracture Fixation, Internal ; methods ; Humans ; Lumbar Vertebrae ; injuries ; surgery ; Male ; Middle Aged ; Retrospective Studies ; Spinal Fractures ; surgery ; Spinal Fusion ; methods

OBJECTIVETo investigate the status of male reproductive health among middle-aged and older men in the urban area of Nanjing.

METHODSWe collected the laboratory results of 884 middle-aged and older men aged 55 - 89 years from the Xuanwu District of Nanjing present for routine physical examinations, including those of blood routine tests, liver and kidney function, blood glucose, blood lipid, and total prostate specific antigen (TPSA), as well as such reproductive hormone indexes as total serum testosterone (TT), free serum testosterone (fT), and sex hormone binding globulin (SHBG). We also obtained the above reproductive hormone indexes from 119 young and middle-aged men aged 20 - 39 years as controls.

RESULTSAging-related changes were found in the 50 percentiles of all the reproductive hormones and relevant parameters but those of TT and E2, with gradual increases in LH, FSH and SHBG and decreases in fT, TSI and fTI. Comparison of reproductive hormones and relevant parameters by Mann-Whitney U test did not show any statistically significant differences in the TT level between any two of the five age groups (20 - 39, 55 - 59, 60 - 69, 70 - 79, and > or = 80 yr) (P > 0.05) except between the control and > or = 80 yr groups and the 60 - 69 and > or = 80 yr groups (P < 0.05), nor in the E2 level between any two groups, nor in the levels of LH and FSH except between the 55 - 59 and 60 - 69 yr groups and the 70 - 79 and > or = 80 yr groups, and nor in the levels of fT and TSI except between the 55 - 59 and 60 - 69 yr groups. However, there were significant differences in the levels of SHBG and fTI between any two age groups. Spearman correlation analysis revealed that fT, TSI, and fTI were correlated negatively with aging and LH (P < 0.05, I r I > 0.5) but weakly positively with cholesterol, blood glucose and hemoglobin (P < 0.05, /r/ < 0.5), SHBG and LH positively with aging, SHBG weakly negatively with blood glucose and hemoglobin, LH weakly negatively with hemoglobin, and TT weakly negatively with aging but positively with hemoglobin.

CONCLUSIONThe levels of serum testosterone, particularly that of fT, declined with aging in middle-aged and older men in the urban area of Nanjing, which may contribute to abnormal lipid metabolism, low hemoglobin and high blood glucose.

Aged ; Aged, 80 and over ; Aging ; blood ; Blood Glucose ; analysis ; Case-Control Studies ; China ; Follicle Stimulating Hormone ; blood ; Humans ; Luteinizing Hormone ; blood ; Male ; Middle Aged ; Prostate-Specific Antigen ; blood ; Sex Hormone-Binding Globulin ; analysis ; Statistics, Nonparametric ; Testosterone ; blood

BACKGROUNDDeveloping an effective vaccine against human immunodeficiency virus type 1 (HIV-1) remains a grand challenge after more than two decades of intensive effort. It is partially due to the lack of suitable animal models for screening and prioritizing vaccine candidates. In this study, we aim to develop a mice model to test HIV-1 vaccine efficacy.

METHODSWe constructed a recombinant vaccinia expressing firefly luciferase and HIV-1 Gag fusion protein based on Tiantan strain, an attenuated but replication-competent poxvirus (rTTV-lucgag). By quantifying the luciferase activity as its read out, we defined the biodistribution of Tiantan strain poxvirus in mice inoculated intraperitoneally and attempted to apply this model to evaluate the HIV-1 vaccine efficacy.

RESULTSOur data demonstrated that the rTTV-lucgag was able to express high level of luciferase (< or = 10(6) relative luciferase units (RLU)/mg protein) and HIV-1 Gag (> 3 folds increase comparing to the control). After intraperitoneal inoculation, this virus had dominant replication in the ovary, uterus, and cervix of mice and the luciferase activities in those organs are significantly correlated with viral titers (r(2) = 0.71, P < 0.01). Pre-immunization with an HIV gag DNA vaccine reduced the luciferase activity in ovary from (6006 +/- 3141) RLU/mg protein in control group to (1538 +/- 463) RLU/mg protein in vaccine group (P = 0.1969).

CONCLUSIONSThe luciferase activity in ovary could represent viral replication in vivo; this rTTV-lucgag/mice model may be suitable to assess the protective efficacy of cytotoxic T-cell responses to HIV Gag with less tedious work and high through-put.

AIDS Vaccines ; genetics ; Animals ; Female ; HIV Infections ; immunology ; prevention & control ; HIV-1 ; genetics ; Humans ; Kinetics ; Luciferases ; genetics ; metabolism ; Mice ; Mice, Inbred BALB C ; Poxviridae ; genetics ; Recombinant Proteins ; genetics ; metabolism ; Virus Replication ; genetics ; gag Gene Products, Human Immunodeficiency Virus ; genetics

OBJECTIVETo establish a new method on stratification analysis when the stratification limits of confounding factors was not clear or contradictory.

METHODData on a study of diabetes mellitus in Guangdong province collected in the year of 1997 and 1998 was analyzed using cluster-stratification analysis.

RESULTSThe efficiency of stratification analysis was improved and the confounding bias was effectively controlled with information bias avoided when the clusters-stratification analysis was applied.

CONCLUSIONThe problem was logically solved using cluster analysis as an assistant stratification means.

Adult ; Age Factors ; Aged ; Bias ; China ; epidemiology ; Cluster Analysis ; Confounding Factors (Epidemiology) ; Data Interpretation, Statistical ; Diabetes Mellitus ; epidemiology ; Epidemiologic Methods ; Humans ; Middle Aged ; Multivariate Analysis ; Reproducibility of Results ; Risk Factors