Objective　To make a preliminary analysis of orthokeratology(OK) for treating myopia.Methods　OK lenses were chosen to treat myopia with or without astigmatism according to the myopia characterizations, then changes of their visions, refractions, corneal curvature and eccedtricities after being treated for ld, 1、2、3、4 weeks were observed once every 4weeks and were followed up for 18 months.Results　Significant changes were observed after being treated. Slight myopia: the diopters decreased-2.75D±0.50D,the horizontal meridians flattened 1.64±0.21, the vertical 0.92±0.27 and the eccedtricities declined 0.47±0.11; Middle myopia: the diopters decreased -5.50D±0.75D,the horizontal meridians flattened 2.16±0.45, the vertical 1.61±0.67, and the eccedtricities declined 0.38±0.07; High myopia:the diopters did -6.75D±0.50D,the horizontal did 3.86±0.56, the vertical 2.97±0.67 and the eccedtricities did 0.32±0.10. The predicabilities of slight and middle myopia were superior to high myopia's.Conclusion　Orthokeratology is a non-traumatic therapy and the clinical application should be careful and scientific.

BACKGROUND:Little data have been available concerning the mechanism of drag resistance and anti-apoptosis in leukemic cells of leukemia children.The majority of studies focus on normal bone marrow mesenchymal stem cells (MSCs) and established stroma cells,but not interaction of MSCs and leukemic cells in leukemia children.OBJECTIVE:To explore the effect of MSCs in leukemia children on the proliferation and apoptosis of leukemic cell strain K562/AO_2.DESIGN,TIME AND SETTING:In vitro cytology experiment was performed at the laboratory of Department of Pediatrics,First Affiliated Hospital of Guangzhou Medical College from December 2007 to August 2008.MATERIALS:MSCs were provided by 30 leukemia children admitted to First Affiliated Hospital of Guangzhou Medical College,including 22 acute lymphoblastic leukemia and 8 acute myeloblastic leukemia.Written informed content was obtained from all families.K562/AO_2 was provided by Tianjin Institute of Hematopathy.METHODS:MSCs were isolated and cultured by Ficoll density gradient method.They were cultured in two conditions:the co-culture of MSCs and K562/AO_2 and K562/AO_2 suspension alone.In co-culture group,1×10~8 /L K562/AO_2 cells at log phase were added to confluent MSCs,and free floating K562/AO_2 cells were discarded after 24 hours.MAIN OUTCOME MEASURES:Effect of MSCs on the growth of K562/AO_2 cells was observed;effect of addamycln on K562/AO_2 cell apoptosis was detected by AnnexinV-FITC method.Cell cycle was determined by flow cytomtry,mdrl gene of K562/AO_2 cell was detected by Taqman-MGB probe real-time PCR.RESULTS:Compared with K562/AO_2 alone,the K562/AO_2 cell co-cultured with MSCs grew slower and the log phase of growth was not significant;the rate of apoptosis in earlier period was significantly decreased (P ＜ 0.05);co-cultured K562/AO_2 G_0-G_1 phase increased,but S phase decreased.No changes in mdr1 gene in cells were found between two culture conditions (P ＞ 0.05).CONCLUSION:In vitro cytology has demonstrated that leukemia children MSCs induce drug resistance of K562/AO_2 cells by changing K562/AO2 cell cycle through adhesion to avoid pro-apoptotic effect of drugs but not related with mdr1 gene.

Engineering and redesign of enzymes are important to industrial biocatalysis. Fusion enzyme technology, based on fusion protein design, is frequently used in multifunctional enzyme construction and enzyme proximity control. Here, we reviewed the recent progress in molecular design strategy and application studies of fusion enzymes. The concept and features of fusion enzymes were introduced, followed by a systematical summary of the design strategy of fusion enzymes. In particular, the effects of different linker properties on fusion enzymes and their possible mechanisms were discussed. In addition, recent studies on fusion enzyme applications were also discussed. Finally, based on our own studies on fusion enzymes and the current research progress, the key problems in fusion enzyme technology and perspectives of this field were discussed.
Biocatalysis ; Biotechnology ; Enzymes ; chemistry ; Protein Engineering ; Recombinant Fusion Proteins ; chemistry

Objective To assess the safety and efficacy of the treatment for symptomatic atherosclerotic high-grade stenosis in middle cerebral artery with Wingspan stent.Methods The medical records of Wingspan stenting for 102 cases with symptomatic middle cerebral artery high-grade stenosis from February 2008 to May 2012 in our hospital were reviewed retrospectively.All of the patients suffered from ischemic stroke or transient ischemic attack ( TIA ) attributed to the atherosclerotic high-grade stenosis in middle cerebral artery and the stenosis of 70%to 99%was confirmed by DSA before the stenting procedure.All the stroke, death, TIA within 30 days after the stenting procedure or during the follow-up beyond 30 days were observed and recorded.In-stent restenosis were recorded after DSA or CTA was performed 6 months later.χ2 test or Fisher exact test was used to compare in-stent restenosis rate among patients with different clinical and pathological conditions.Results Stenting procedure were successfully performed in 100 patients (98.0%,100/102).The mean degree of stenosis was reduced from (81.0 ±8.4)% to (15.3 ±6.7)%right after surgery.Eight adverse cardiovascular events (7.8 %, 8/102) occured within 30 days ,including seven stroke or death ( 6.9%, 7/102 ) and 1 TIA.The mean clinical follow-up duration was ( 29 ± 15) months in 82 patients, and 9 ischemic events were documented (4 cases of ipsilateral recurrent stroke , 3 cases of ipsilateral TIA, and 2 cases of contralateral ischemic stroke ).The mean radiological follow-up duration was (11 ±9) months in 55 patients.Among them, 8 patients (14.3%) had in-stent restenosis and 3 patients had symptomatic restenosis.The restenosis rate in patients with age ≤49 years.(25.0%,7/28) was higher than those with age >49 years ( 3.7%,1/27 ) ( P>0.05 ).The restenosis rate in patients with lesion size>7.5 mm(25.0%,7/28) was higher than those with lesion size ≤7.5 mm (3.7%,1/27)(P>0.05).Conclusions The treatment of symptomatic middle cerebral artery high-grade stenosis with Wingspan system was relatively safe and associated with a low perioperative complication rate.The long-term efficacy of the treatment for symptomatic atherosclerotic high-grade stenosis in middle cerebral artery with Wingspan stent is prominent.

Objective:To investigate the effect of thrombus burden on the clinical outcome of endovascular recanalization in large vessel occlusive stroke.Methods:Patients with acute anterior circulation occlusion who underwent endovascular treatment within 24 hours after onset in Zhengzhou University People′s Hospital from January 2018 to December 2019 were retrospectively collected. According to the clot burden score (CBS) of DSA, total objectives were divided into CBS≥6 group (24 cases) and CBS<6 group (38 cases). Clinical data of the two groups were collected and the modified Rankin scale (mRS) was used to evaluate the clinical outcome at 90 days after surgery. Independent sample t-test, Wilcoxon rank sum test and χ 2 test were used to compare the clinical data between the two groups. Independent risk factors affecting the clinical outcome were analyzed by binary logistic regression. Results:There were no statistically significant differences in basic demographic data, stroke risk factors and other factors between the CBS≥6 group and CBS<6 group ( P>0.05).The proportion of using tirofiban after surgery in the CBS≥6 group (63.2%, 24/38) was lower than that in the CBS<6 group (87.5%, 21/24) (χ2=4.380, P=0.044). The discharge NIHSS score of the CBS≥6 group was [5.0 (3.3, 7.8) points] lower than CBS<6 group [8.5 (1.8, 14.5) points] ( Z=5.221, P=0.022). The proportion of postoperative mRS 0-2 was (91.7%, 22/24) in the CBS≥6 group higher than CBS<6 group(39.5%, 15/38) (χ2=20.486, P=0.001), there were no statistically significant differences between the two groups ( P<0.05). The results of binary logistics regression analysis showed the CBS groups (OR=0.042, 95%CI 0.007-0.244 , P=0.001) was an independent risk factor affecting good outcome. Subgroup analysis of whether tirofiban was used or not showed there was no statistically significant difference in clinical prognosis between the two groups ( P>0.05). Conclusions:The clinical outcome of CBS≥6 group is significantly better than that of CBS<6 group, and patients with small thrombus burden are more likely to get a good clinical outcome of 90 days.

Objective:This study compares the magnetic resonance imaging (MRI) appearance of two types of breast tissue markers to investigate the appropriate clinical application of the markers.Methods:Breast MRI of 69 patients (78 masses) with breast tissue markers had been placed were analyzed retrospectively from November 2015 to August 2018 in our hospital. The sizes and shapes of breast tissue markers were assessed in axial fat-suppressed T2-weighted images, T1-weighted images and contrast-enhanced T1-weighed images.Results:The length of the coil nickel-free stainless steel markers were greater than ribbon titanium markers, with statistical difference in fat-suppressed T2-weighted images ( P=0.039). In contrast-enhanced T1-weighted images, all coil nickel-free stainless steel markers showed >6 mm diameter and round shape, and ribbon titanium markers showed >6 mm diameter ( n=20) or ≤6 mm diameter ( n=8), and round ( n=20), dot ( n=7) or band ( n=1) shapes. The categories of sizes and shapes in two types of breast tissue markers both had statistical significance ( P<0.001, P<0.001). Conclusions:Small breast lesions with breast tissue markers are not suitable for MRI evaluation. The artifact of ribbon titanium markers is smaller than coil nickel-free stainless steel markers, so they have less impact for lesions. The choice of the breast tissue markers and image evaluation methods should depend on the different clinical conditions.

Objective To study the dietary nourishment of adult patients with leukemia and compare acute leukemic patients with chronic leukemic patients. Methods Adopting dietary review of 24 hours and seven consecutive days of dietary records method to obtain the food category and quantity of 122 patients with acute leukemia and 10 patients with chronic leukemia. Using statistic software SPSS11.0 to calculate the patients'intake of various kinds of nutfiments. and the difiences between acute and chronic leukemic patients were analyzed. Results The rate of most ontrients of patients'intake reaches RNI/AI is lower,especially vitamin A,vitamin C and caleium.There's a tendency that intake diet,energy and nourishments of acute leukemic patients is lower than that of those chronic leukemic patients. Conclusion There is a tendency of unbalanced dietary intakes in leukemic patients.including the low intakes.There is the tendency that nutritional status of acute leukemic patients iS poorer than that of chronic leukemic patients.

Objective To investigate the safety of endovascular thrombectomy in acute ischemic stroke patients with pre-existing intracranial aneurysms. Methods Seven patients with acute ischemic stroke combined with intracranial aneurysms, admitted to and received endovascular treatment in our hospital from January 2014 to December 2016, were chosen. The clinical data and safety were analyzed retrospectively. Results All patients with pre-existing intracranial aneurysms suffered acute large artery occlusion achieved successful endovascular re-canalization, and one patient suffered subarachnoid hemorrhage due to the rupture of aneurysm during the procedure. Three patients had grading 2b of Thrombolysis in Cerebral Infarction (TICI), and 4 had grading 3 of TICI. Four patients had 0-2 scores of modified Rankin Scale (mRS), one had 3 scores, and two died. Conclusion Endovascular thrombectomy in acute ischemic stroke patients with pre-existing intracranial aneurysms is safe.

Objective:To investigate the safety and efficacy of endovascular treatment in acute anterior circulation massive cerebral infarction and its prognostic factors.Methods:A retrospective analysis was performed on clinical data of 34 patients with acute anterior circulatory massive cerebral infarction who received intravascular treatment in our hospital from February 2018 to December 2019. The perioperative hemorrhage rate and mortality rate were analyzed in these patients. Modified Rankin scale (mRS) scores were taken as the evaluation standard in the prognoses of these patients during the 90 d of follow up, and the influencing factors affecting the prognoses of patients with massive cerebral infarction were analyzed.Results:The operation was successful in 30 patients (88.2%); the operation time was (97.41±54.58) min, and the number of thrombolysis was (1.91±0.75) times. Distal embolization occurred in 4 patients (11.8%); there were 3 patients with non-symptomatic hemorrhage (8.8%) and 3 patients with symptomatic hemorrhage (8.8%). Cerebral hernia occurred in 7 patients (20.6%); there were 5 deaths (14.4%). During the 90 d of follow up, 13 patients (38.2%) had good prognosis, and 21 (61.8%) had poor prognosis; there were statistically significant differences in NIHSS scores at admission, infarction locations in diffusion weighted imaging, vascular occlusion locations in DSA, pecentages of patients accepted preoperative intravenous thrombolysis and patients with cerebral hernia between the two groups ( P<0.05). NIHSS scores at admission ( OR=0.817, 95% CI: 0.682-0.980, P=0.029), thrombus load scale scores ( OR=5.981, 95%CI: 1.827-19.575, P=0.003), vascular occlusion locations in DSA ( OR=0.031, 95% CI: 0.003-0.311, P=0.003) and pecentage of patients accepted preoperative intravenous thrombolysis ( OR=0.092, 95% CI: 0.010-0.838, P=0.034) were independent factors influencing the prognoses of emergency intravascular treatment. Conclusions:Endovascular recanalization can achieve a relatively good prognosis in patients with massive cerebral infarction. Patients with low NIHSS scores, high thrombotic load scale scores, and middle cerebral artery occlusion, and patients accepted direct intravascular treatment have relatively good prognosis.

Objective:To investigate the differences of white matter diffusion properties between vulnerable and resistant individuals to continuous attention after sleep deprivation.Methods:According to the psychomotor vigilance test performance before and after sleep deprivation, the participants were divided into the vulnerable group( n=24) and resistant group( n=25). All participants underwent diffusion tensor imaging (DTI) scans.Tract based spatial statistics(TBSS) was used to compare fractional anisotropy(FA), mean diffusivity(MD), axial diffusivity(AD), radial diffusivity(RD) maps between the two groups.Spearman correlation analysis was conducted by SPSS 24.0 to investigate the relationships between the altered DTI metrics and PVT task performance. Results:(1) Compared with resistant group, FA value of vulnerable group decreased in the body of corpus callosum(x, y, z=-8, 9, 25, t=-7.855), right superior longitudinal fasciculus(x, y, z=-39, -7, 26, t=-6.252), bilateral anterior limb of internal capsule(x, y, z=-13, 8, 13, t=-5.235; x, y, z=12, 8, 3, t=-5.024) and right posterior thalamic radiation(x, y, z=-26, -56, 17, t=-5.469)(TFCE corrected, P<0.05, cluster size≥50 voxel). (2) Compared with resistant group, MD value of vulnerable group increased in the body of corpus callosum(x, y, z=-3, -6, 26, t=7.613), right superior longitudinal fasciculus(x, y, z=-31, -19, 38, t=5.314), bilateral anterior limb of internal capsule(x, y, z=-16, 7, 8, t=6.898; x, y, z=15, 5, 7, t=6.652), splenium of corpus callosum(x, y, z=27, -53, 17, t=6.541), and AD value increased in the right superior longitudinal fasciculus(x, y, z=-33, -19, 39, t=4.892), splenium of corpus callosum(x, y, z=-22, -49, 21, t=5.450), genu of corpus callosum(x, y, z=4, 26, 0, t=4.332), as well as RD value increased in the right superior corona radiata(x, y, z=-17, 1, 33, t=7.558), body of corpus callosum(x, y, z=4, -8, 26, t=6.699), right anterior limb of internal capsule(x, y, z=-12, 7, 3, t=5.212) (TFCE corrected, P<0.05, cluster size≥50 voxel). (3) Correlational analysis revealed that the negative correlations were found between PVT task performance and the FA value in the right superior longitudinal fasciculus( r=-0.492, P<0.001), right anterior limb of internal capsule( r=-0.510, P<0.001), right posterior thalamic radiation( r=-0.502, P<0.001) and body of corpus callosum( r=-0.464, P<0.001). The positive correlations were found between PVT task performance and the MD value in the body of corpus callosum( r=0.500, P<0.001), right superior longitudinal fasciculus( r=0.499, P<0.001), splenium of corpus callosum( r=0.462, P<0.001), right anterior limb of internal capsule( r=0.471, P<0.001), and AD value in right superior longitudinal fasciculus( r=0.643, P<0.001), as well as RD value in right superior corona radiate( r=0.498, P<0.001) (Bonferroni corrected, P<0.003). Conclusion:Differences in the microstructural characteristics of white matter fiber tracts in specific brain regions may constitute the potential neuropathological basis for the phenotypes of vulnerable and resistant individuals to continuous attention after sleep deprivation.