AIM: To investigate the topography of the anterior surface of the human crystalline lens. ·METHODS: A Non-contact three-coodinate measuring system was utilized to scan the anterior surfaces of 8 human eye lenses in vitro. Acquired data were processed and computer models of the anterior lens surfaces were made using the program (Surfacer v 10.0). The to-pography of the anterior lens surfaces were established. Radii of curvature were measured at preset spots over the lens surfaces and two way analysis of variance was performed. The data were analysed to determine whether the radius of curvature varied systematically with the position on the lens surface from which the measurement was made. Lens surface asymmetric index (LSAI) was defined and calculated. The vertical and horizontal meridians of the modeled lens were calculated, and the best curve fit to any conic section was determined. ·RESULTS: The topography of the anterior lens surface indicated that the central zone (the central radius of curvature is (9.09±0.80)mm was steeper than that of the peripheral zone(17.05±2.20)mm. Two way analysis of variance of the radii of curvature at preset spots over the lens surfaces showed that the differences were statistically significant (P ＜ 0.05). Curve regression of radii of curvature at preset spots and their distances to the surface center revealed that the correlation of them was the third power function. LSAI increased steadily from the lens surface center(0.013±0.005) to the periphery(0.184± 0.065). The dots on the horizontal and vertical meridians were fit to four kinds of curves, and the determinate coefficient of hyperbola fit were the largest (0.9989-0.9999). ·CONCLUSION: The anterior lens surface is imperfectly rotational symmetric. Moreover, the nearer to the center, the more rotational symmetric it is. Radii of curvature increase nonlinearly from the surface center to the periphery. Anterior lens surface is typically hyperbolic.

Glaucoma,especially common primary open-angle glaucoma and primary angle-closure glaucoma,shows high genetic heterogeneity. The causing-disease genes known are difficult to explain some glaucomatous cases,and the study on the susceptibial gene of glaucoma do not achieve new breakthroughs. Combined with the newest progression in genetic study of glaucoma,some views were proposed in this paper in order to better understand the updating study of the pathogenesis mechanism.

Background Posterior capsular opacification (PCO) following cataract extracapsular extraction is a major cause of the reduction of visual acuity.Topical administration of eye drops is a research hotspot for the prevention of PCO.Objective This study was to evaluate the release of cyclosporine A-loaded chitosan nanoparticles (CyA-CS-NP) by ionic gelation in vitro and its feasibility of modification of the surface of polymethylmethacrylate intraocular lens (PMMA IOL) with CyA-CS-NP.Methods The CS-NP and CyA-CS-NP were prepared by ionic gelation of CS with sodium tripolyphosphate.The characteristics of CS-NP,such as the appearance and mean size,and drug entrapment efficient (EE),loading capacity (LC),and the drug release were studied ; the CyA content on the IOL surface was detected by high performance liquid chromatography (HPLC).The IOL surface modified with CyA-CS-NP was observed by scanning electron microscope and X-ray photoelectron spectroscopy technique (XPS),the changes of elements and chemical bond types between simple plasma processed IOL and CyA-CS-NP modified IOL were analyzed.The transmittance at the wavelength of 360-490 nm and refraction of IOL were detected using back focal length method and spectrophotometer,and the effective resolution of IOL was evaluated according to the instruction of ISO/CD 11979-2.Loops anti fatigue test of IOL referred to the criteria of ISO/CD 11979-3.Results The CS-NP and CyA-CS-NP showed monodisperse,uniform appearance similar to spherical shape with a mean size of (158±18) nm and (219±29) nm,respectively.The CyA-CS-NP had high CyA association efficiency and loading capacity (64.2％ and 7.6％).In vitro release study revealed a fast release on the first day followed by a increased drug release during an 11-day following up.The sustained release was approximately 46.6％ at day 1 and 77.7％ at day 12,respectively.The surface of IOLs with cling film was smooth without CS-NP;while the edge of IOLs appeared a layer of CyA-CS-NP after modification.XPS analysis displayed some elements such as phosphonium,CNH2 and O =CN that appeared on the modified surface,indicating that CyA-CS-NP existed on the surface of IOLs edge.The mean quality of CyA on three IOLs surface after modification was 171.88 μg.The diopter,distinguishing ability and transmittance of modified IOL were (16.64±0.23) D,(90.28 ± 0.25) ％ and (73.57 ±0.62) ％,and those of unmodified IOL were (16.62±0.29) D,(90.28±0.21) ％,(73.61±0.60)％,without significant differences between them (t =0.381,0.078,2.291,all at P ＞ 0.05).The antifatigue ability of loops complied with the criteria of ISO/CD 11979-3.Conclusions The optical property and antifatigue ability of loops of the edge-modified IOLs by CyA-CS-NP reach the normal standard and meet the requirement of clinic application.The edge-modified IOLs by CyA-CS-NP can be a delivery system for intraocular drug release.

Communicable Diseases ; transmission ; Decision Support Techniques ; Humans ; Models, Theoretical ; Risk Factors

Abdomen ; Acupuncture Therapy ; methods ; Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Male ; Medicine, Chinese Traditional ; Middle Aged ; Vertigo ; therapy

Objective To analyze the efficacy of posterior medial mini-incision combined with arthroscopic double SMC knot fixation using high-strength suture in the treatment of posterior cruciate ligament (PCL) avulsion fractures. Methods Sixty patients with PCL avulsion fractures were selected as the study subjects, and randomly divided into anchor fixation group (treated with anchor fixation, n=30) and high-strength suture fixation group (treated with double SMC knot fixation using high-strength suture, n=30). Follow-up data were recorded for both groups. The fracture healing time, operative time, as well as changes in knee function assessed by the Lysholm score, International Knee Documentation Committee (IKDC) score and knee range of motion before and after treatment were compared between the two groups. Results The follow-up period for all 60 patients ranged from 6.5 to 22.5 months, with a mean time of (13.50±7.49) months. No patients were lost during follow-up. Four patients in each group showed a weakly positive drawer test, but no restrictions in knee extension were observed. There were no statistically significant differences in postoperative Lysholm scores, IKDC scores and knee range of motion between the two groups (P>0.05). The fracture healing time and operative time in the high-strength suture fixation group were (11.27±0.87)weeks and (53.73±4.67) minutes, respectively, which were significantly shorter than (12.35±1.03) weeks and (64.06±5.13) minutes in the anchor fixation group (P < 0.05). Conclusion Both posterior medial mini-incision combined with arthroscopic double SMC knot fixation using high-strength suture or anchor fixation are effective in treating PCL avulsion fractures. However, the high-strength suture double SMC knot fixation method exhibits shorter operative time and fracture healing time, as well as lower operative difficulty.

Objective: To evaluate value of application of intravascular ultrasound imaging (IVUS) in diagnosing borderline lesions in left anterior descending artery (LAD) and left main coronary artery (LM). Methods: According to results of coronary angiography (CAG) in 60 cases with coronary borderline lesions, including 20 cases in LM, 20 cases in proximal segment of LAD and 20 cases in middle segment of LAD, the diagnostic value of IVUS in coronary borderline lesion was evaluated. Results: Compared with CAG, mean diameter stenosis rate of each coronary artery [LM: (65.3l±7.81) % vs. (75.28±8.89) %，proximal segment of LAD: (66.67±8.79) % vs. (78.89±7.88) %，middle segment of LAD: (71.55±6.83) % vs. (75.3l±7.81) %, P<0.01 all] significantly increased in IVUS. The differences of detection rate of plaque calcification and plaque rupture were no significant between CAG and IVUS（＞0.05）. Conclusion: Different degrees of underestimation of coronary artery stenosis exist in CAG, especially in proximal segment of LAD. IVUS can be an effective complement to CAG.

BACKGROUND: Hyperbaric oxygen therapy has been considered as an effective therapy for prevention and cure of cerebral infarction traditionally.However, some scholars suggested that hyperbaric oxygen therapy could also result in cerebral infarction, although the mechanism is unclear.OBJECTIVE: To investigate the cause of cerebral infarction due to hyperbaric oxygen therapy.DESIGN: Case-control trial with patients as subjects.SETTING: Department of Hyperbaric Oxygen, Guangzhou General Hospital of Guangzhou Military Area Command of Chinese PLA.PARTICIPANTS: From December 1996 to March 1998, 192 inpatients receiving hyperbaric oxygen therapy were recruited into the trial from the Department of Hyperbaric Oxygen, Guangzhou General Hospital of Guangzhou Military Area Command of Chinese PLA. There were 127 males and 65 females aged 9-78 years. Patients admitted to the department of hyperbaric oxygen were eligible if they had hypoxia or ischemia induced disease and had no contraindication to hyperbaric oxygen therapy. Patients were recruited into the study regardless of the gender, and all patients and their family gave informed consent before enrollment. Patients were excluded if they did not receive hyperbaric oxygen therapy. According to the Diagnosis and Curing Criteria of Clinical Diseases, 6 patients developed into cerebral infarction during hyperbaric oxygen therapy, 3 males and 3 females, at the age of 51-76 years.METHODS: Patients were exposed to oxygen at 0.2 MPa in hyperbaric chamber used for many persons, and inhaled oxygen with a facemask once a day for 80 minutes with an interval of 10 minutes at the 40th minute. Ten days was considered as one course. Background and risk factors were analyzed in 6patients with cerebral infarction and 186 patients without cerebral infarction.MAIN OUTCOME MEASURES: Analysis of distribution of risk factors among cerebral infarction patients, and risk factor levels in patients without cerebral infarction.RESULTS: Among the 6 patients with cerebral infarction, hyperlipidemia was in all 6 cases, hypertension in 5 cases, primary cerebral infarction or hemorrhage in 5 cases, ≥ 60 years old or hyperviscosity in 4 cases, and diabetes mellitus in 1 case. Risk factor aggregation existed in the patients with over four risk factors. Of the 6 patients with cerebral infarction due to hyperbaric oxygen therapy, 5 cases had 4 risk factors and 1 had 5 risk factors. Of the 186 patients without cerebral infarction, 25 cases had 4 risk factors, and no case had 5 risk factors. The risk factor aggregation was relatively impossible (x2 = 54. 37, P ＜ 0. 05 ).CONCLUSION: Risk factor aggregation was found in all cerebral infarction patients, which is closely associated with the probability of cerebral infarction resulting from hyperbaric oxygen therapy.

Objective To study the prospective memory and the severity of the impairment of event- based prospective memory(EBPM)and time-based prospective memory(TBPM)in normally aging adults. Methods We set a neuropsychological battery to measure the education-matched 40 adults and 40 normally aging adults who were given EBPM and TBPM tasks.Results Compared with the young controls(EBPM, 6.25?1.60;TBPM,5.38?0.87),both EBPM(2.50?0.85)and TBPM(4.93?1.07)in the elderly had been impaired,especially EBPM(t = 13.117,P

BACKGROUND: It is commonly believed that hyperbaric oxygen (HBO)plays a neuroprotective role in the prevention and treatment of cerebral infarction (CI), however hyperbaric oxygen therapy (HBOT)-induced CI was also reported.OBJECTIVE: To investigate the risk factors of HBOT-induced CI.DESIGN: Case analysis with patients as subjects.SETTING: At the Department of Hyperbaric Oxygen of Guangzhou General Hospital of Guangzhou Military Command Area of Chinese PLA.PARTICIPANTS: Totally 192 inpatients receiving HBOT were selected from the Department of Hyperbaric Oxygen of Guangzhou General Hospital Guangzhou Military Command Area of Chinese PLA between December 1996 and March 1998, including 127 males and 65 females with age ranging from 9 to 78 years old. Totally 6 patients, 3 males and 3 females, suffered from CI during HBOT, with the age from 51 to 76 yeas.METHODS: The background factors of 192 patients who HBOT METHODS and 6 cases with induced CI were analyzed.MAIN OUTCOME MEASURES: Symptoms, signs and skull CT or MRI.RESULTS: Data of 192 patients were dealt with intentionally and all were statistically analyzed without miss. ① The incidence of CI during HBOT was 0.3% (6/192). ② The risk factors of HBOT-induced CI included: age of ≥ 60 years, hypertension, hyperlipidemia, primary CI or cerebral hemorrhage, blood hyperviscosity and diabetes, and the incidence would greatly increased in those who has 4 or more than 4 risk factors, but seldom with less than 4 risk factors.CONCLUSION: The cluster level of risk factors was closely related with the incidence of HBOT-induced CI.