Analysis of the rates of emulsification in intraocular silicone oil tamponades of differing viscosities

AIM:To investigate the rates of emulsification in silicone oil(SO)tamponades of differing viscosities used during pars plana vitrectomy(PPV)in the treatment of complicated vitreoretinal diseases.METHODS:This study was a prospective randomized clinical trial.Totally 290 cases with greater likelihoods of secondary detachment were included and randomly grouped into either Siluron 2000(n=143)or Siluron 5000(n=147)SO tamponades with 23-gauge PPV.Patient followups and data analyses were conducted 1,3,6,and 12 mo post-surgery.RESULTS:The time of the SO emulsification ranged from 1 to 17 mo,with a mean of 7.3±4.2 mo.The Siluron 5000 group showed a slower emulsification rate in comparison to the Siluron 2000 group.The Siluron 2000 group took a shorter time to show signs of emulsification,necessitating earlier SO removal.However,there were no significant differences in the occurrence of complications,including secondary retinal detachment,cataract,corneal abnormality,high intraocular pressure and hypotony.CONCLUSION:The Siluron 2000 SO tamponade shows a faster rate of emulsification than the Siluron 5000 SO,necessitating earlier removal.Both groups show similar results in terms of anatomical success and visual acuity outcome,and there is no significant difference between the SOs regarding the occurrence of complications.

铬污染区地下水对大鼠肝脏功能及Caspase-3和PARP表达的影响

目的研究铬污染区地下水对大鼠肝功能、Caspase-3和聚腺苷二磷酸-核糖聚合酶(PARP)表达的影响。方法将10只健康SD孕鼠随机分成空白组、地下水组、低铬组、中铬组及高铬组,每组2只。分别灌胃蒸馏水、铬含量为28.64mg/L的铬污染区地下水,以及剂量为0.8、4.0和20.0mg/kg的重铬酸钾溶液。21d后小鼠断奶,按母鼠分组直接灌胃,灌胃剂量不变(0.5ml/100g),1次/d,连续灌胃21周。解剖子代大鼠后取血液及肝组织,用原子吸收光谱仪(石墨炉法)检测肝组织中的铬含量及血清中TP、ALB、GLB的含量,以及AST、ALT、ALP的活力,用苏木精-伊红(HE)染色法制作切片,观察肝脏的病理变化,并用免疫组织化学法检测Caspase-3和PARP的表达情况。结果与空白组比较,地下水组与各剂量重铬酸钾染毒组肝脏中铬的含量均升高,且随着染毒剂量的升高,子代大鼠肝脏中铬含量呈上升趋势,差异有统计学意义(P<0.05)。地下水组与各剂量重铬酸钾染毒组血清中TP、ALB、GLB的含量均升高,中铬组和高铬组与空白组间的差异有统计学意义(P<0.05)。地下水组与各剂量重铬酸钾染毒组血清中的AST、ALT、ALP活力均高于空白组,各剂量重铬酸钾染毒组与空白组间的差异有统计学意义(P<0.05)。HE染色结果显示地下水组与重铬酸钾染毒剂量组的肝细胞表现为不同程度的嗜酸性样变,排列紊乱,细胞质间隙加大及空泡性样变。免疫组织化学结果显示,地下水组Caspase-3和PARP阳性表达率与低铬组相仿,各剂量重铬酸钾染毒组随着重铬酸钾浓度升高,肝细胞阳性率升高。结论六价铬长期暴露对大鼠的肝功能造成一定损伤,且使肝细胞Caspase-3和PARP表达增强。

Correlations between the optic nerve head morphology and ocular biometrics in highly myopic eyes

AIM： To analyze peripapillary atrophy β/γ zone （PPA-β/γ） and the optic disc ovality index, and to assess their associations with the axial length （AL）, refractive error, best corrected visual acuity （BCVA）, choroidal thickness （CT）, and age in highly myopic eyes. METHODS： This was a retrospective observational case series. The study included 667 patients consecutively examined for highly myopic eyes [spherical equivalent ≤-6.0 diopters （D） and AL≥26 mm] with or without myopic retinopathy. Each patient went through a comprehensive ophthalmological examination that included spectral domain optical coherence tomography （SD-OCT） of the macula, A-mode ultrasonography, and a cycloplegic refraction test. The ovality index and PPA-β/γ area were measured from optic disc photographs. RESULTS： A significant association was seen between PPA-β/γ area and the ovality index （P=0.000, r=-0.232）. The PPA-β/γ area increased significantly with a longer AL, older age, worse BCVA, higher refractive error, and thinner choroid （P〈0.01）. The oval disc was significantly correlated with a longer AL, older age, worse BCVA, higher refractive error, larger PPA-β/γ area, and thinner choroid （P〈0.01）. CONCLUSION： The PPA-β/γ zone and ovality index in highly myopic eyes show distinct associations with the AL, refractive error, BCVA, age, and CT.

Epidemiological characteristics of 369 tuberculosis patients with multidrug resistance inHainan Island: A cross-sectional study

Objective:To investigate the epidemic characteristics of multidrug resistant tuberculosis in Hainan,China,to provide basic information and theories for the prevention and control of multidrug resistant tuberculosis.Methods:A retrospective descriptive epidemiological study was conducted.Data of multidrug resistant tuberculosis in Hainan Island from January 1,2014 to December 31,2019 were collected for statistical analysis.The counting data were described by frequency(percentage),and the measurement data were described by mean±standard deviation.Chi square test was used to compare the differences between different groups.If P<0.05,the difference was statistically significant.Results:From 2014 to 2019,the multidrug resistant rate of tuberculosis in Hainan Island was 24.9%(369/1484),8.0%(63/791)in newly-treated tuberculosis,and 44.2%(306/693)in retreatedmultidrug resistant rate of tuberculosis in Hainan Island was 24.9%(369/1484),8.0%(63/791)in newly-treatedtuberculosis,and 44.2%(306/693)in retreated tuberculosis.The multidrug resistant rate of newly-treated tuberculosis decreased by 0.05%per year,while that of retreated tuberculosis increased by 0.03%per year.multidrug resistant tuberculosis was mainly distributed in the city of Haikou(83 cases),Danzhou(44 cases),Wenchang(42 cases),Wanning(37 cases)and Dongfang(32 cases),accounting for 64.5%of all multidrug resistant tuberculosis.Among 369 multidrug resistant tuberculosis,81.0%were male.The proportion of newly-treated cases was 17.1%(63/369),while the proportion of retreated cases was 82.9%(306/369),which was significantly higher than that of newly-treated cases.The multidrug resistant rate of tuberculosis in different years was different.Conclusion:The drug resistance rate of tuberculosis in Hainan Island is higher than the national average level,which needs attention.The epidemiological characteristics of multidrug resistant tuberculosis with different treatment history were different.

Ophthalmic findings in two cases of methanol optic neuropathy with relapsed vision disturbance

【正】Dear Sir,We hereby report two cases of methanol optic neuropathy with relapsed vision disturbance.Methanol intoxication appears after accidental or suicidal oral ingestion of industrial solvents or cleaning and antifreeze liquids or occasionally is due to fraudulent adulteration of wine or other alcoholic beverages.Its ingestion can cause severe visual disturbances and the outcomes of visual disturbances vary diffusively.Some completely or partially recovered,and some suffered

Influence of slip ratio on worn-surface microstructure and fatigue wear behavior of D2 wheel steel

To investigate the worn-surface microstructure and fatigue cracks in D2 wheel steel under the pure rolling and 0.5% slip ratio conditions,a rolling wear test using a GPM-40 wear machine to simulate the wheel/rail operation was performed. After testing,a transmission electron microscope,a scanning electron microscope with electron backscatter diffraction,and micro-hardness testers were used to characterize the microstructure and fatigue cracks.The surface microstrncture and hardness of the pure rolling sample were in a steady state after 8 × 10^4 cycles;however,the 0.5% slip ratio sample reached a steady state after 7 × 10^3 cycles.Regardless of whether the test uses the slip ratio,the orientation of lamellar pearlites gradually became parallel to the surface and a portion of lamellar cementites was fragmented and dissolved during the formation of steady-state microstructure.The slip ratio accelerates this process.The hardening mechanism of the samples shows a decrease in the lamellar spacing of pearlite and the refinement of proeutectoid ferrite (PF).As the number of cycles increased,plastic deformation of samples became increasingly severe and the wear mechanism of the samples was fatigue wear in steady state.The sample surfaces formed shallow cracks,which gradually peeled off.The slip ratio accelerated the initiation and propagation of fatigue cracks because of the high friction stress on the contact surface.Most fatigue cracks initiated at the interface of pearlite and PF and in the PF region.

Decreased Diagnostic Accuracy of Multislice Coronary Computed Tomographic Angiography in Women with Atypical Angina Symptoms

Background： Multislice computed tomography （MSCT） coronary angiography （CAG） is a noninvasive technique with a reported high diagnostic accuracy for coronary artery disease （CAD）. Women, more t＇requently than men, are known to develop atypical angina symptoms. The purpose of this study was to investigate whether the diagnostic accuracy of MSCT in women with atypical presentation differs from that in men. Meihods： We enrolled 396 in-hospital patients （141 women and 255 men） with suspected or proven CAD who successively underwent both MSCT and invasive CAG. CAD was defined as any coronary stenosis of≥50% on conventional invasive CAG, which was used as the reference standard. The patients were divided into typical and atypical groups based on their symptoms of angina pectoris. The diagnostic accuracy of MSCT, including its sensitivity, specificity, negative predictive value, and positive predictive valne （PPV）, was calculated to determine the usefulness of MSCT in assessing stenoses. The diagnostic performance of MSCT was also assessed by constrtlcling receiver operating characteristic （ROC） curves. Resulis： The PPV （91% vs. 97%,Х^2 = 5.705, P 〈 0.05） and diagnostic accuracy （87% vs. 93%, Х^2 = 5.093, P〈 0.05） of MSCT in detecting CAD were lower in women than in men. Atypical presentation was an independent influencing lactor on the diagnostic accuracy of MSCT in women （odds ratio = 4.94, 95% confidence intervals： 1.16 20.92, Walds 4.69, P 〈 0.05）. Compared with those in the atypical group, women with typical angina pectoris had higher PPV （98% vs. 74%,Х^2= 17.283. P 〈 0.001 ）, diagnostic accuracy （93% vs. 72%,Х^2 = 9.571, P 〈 0.001）, and area under the ROC curve （0.91 vs. 0.64, Z= 2.690, P〈0.01）inMSCTdiagnosis. Conclusions： Although MSCT is a reliable diagnostic modality for the exclusion of significant coronary artery stenoses in all patients, gender and atypical symptoms might have some influence on its diagnostic accuracy.

Influence of Ca treatment on particle-microstructure relationship in heat-affected zone of shipbuilding steel with Zr-Ti deoxidation after high-heat-input welding

The effects of Ca treatment on the particle, microstructure, and toughness of heat-affected zone (HAZ) of shipbuilding steel with Zr-Ti deoxidation after high-heat-input welding were investigated. The simulated welding at a high-heat-input welding of 200 kJ/cm was carried out using Gleeble-3800 welding simulation. Then, particle characteristics were characterized using an Aztec-Feature automatic particle analysis system. Additionally, an in-situ observation experiment was performed to study the relationships between particle and microstructure by high-temperature confocal laser scanning microscopy (HT-CLSM). The results indicated that the average HAZ toughness at -40 ℃ was increased from 183 to 290 J by adding 0.0026 wt.% Ca. Meanwhile, the formation of acicular ferrite ratio was increased from 49.34% to 60.28% due to the addition of Ca. The scanning electron microscopy results clearly showed that CaO-Al_(2)O_(3)-TiOx-ZrO_(2)-MnS particles could act as effective nucleation sites for the formation of acicular ferrite, which has been verified by the observation of the particle-microstructure relationship under HT-CLSM. Furthermore, particle characterization results show that the cumulative frequency of particles with the size of 1-3 lm was 33.2% in HAZ of Zr-Ti shipbuilding steel but 66.2% in HAZ of Zr-Ti-Ca shipbuilding steel.