ObjectiveTo explore the light sensitivity and kinetic of the new optogenetics tools Channelrhodopsin-XXM2.0 (XXM2.0) and Channelrhodopsin-PsCatCh2.0 (PsCatCh2.0), and analyze whether they could be used to restore the visual function by optogenetics.MethodsMolecular biology techniques were used to link the gene fragments of XXM2.0 and PsCatCh2.0 to the vector pCIG(c)-msFoxn3 containing ampicillin resistant screening gene and reporter gene to form new plasmid pCIG(c)-msFoxn3-XXM2.0 and pCIG(c)-msFoxn3-PsCatCh2.0. The constructed plasmids were transfected into HEK 293T cells, and light responses were recorded in the whole cell mode with the HEKA patch clamp system. The photocurrent was recorded under three light intensity included 2.7×1016, 4.7×1015, and 6.4×1014 photons/(cm2·s). And then, XXM2.0 and PsCatCh2.0 were stimulated with 2.7×1016 photons/(cm2·s) and fully recovered. The opening and closing time constants were analyzed with Clampfit 10.6 software. At the same light intensity, photocurrents of XXM2.0 and PsCatCh2.0 were recorded by the light pulse stimulating of 2-32 Hz. The current attenuation was analyzed at long intervals of 4000 ms and short intervals of 200 ms after repeated stimulation. Comparisons between groups were performed by independent samples t test.ResultsRestriction endonuclease sites of EcoRⅠ and EcoRⅤ were successfully introduced at XXM2.0 and PsCatCh2.0 sequences. When the digestion was completed, they were ligated by T4 DNA ligase to construct new plasmids pCIG(c)-msFoxn3-XXM2.0 and pCIG (c)-msFoxn3-PsCatCh2.0, and then transfected on HEK 293T cells. The light intensity dependence was showed in XXM2.0 and PsCatCh2.0. The greater light intensity was accompanied by the greater photocurrent. Under the light intensity 6.4×1014 photons/(cm2·s) below the retinal safety threshold, large photocurrent was still generated in XXM2.0 and PsCatCh2.0 with 92.8±142.0 and 13.9±5.6 pA (t=1.24, 1.24; P=0.28, 0.29). The opening time constants of XXM2.0 and PsCatCh2.0 were 23.9±6.7 and 2.4±0.8 ms, and the closing time constants were 5803.0±568.2 and 219.9±25.6 ms. Compared with PsCatCh2.0, the opening and closing time constant of XXM2.0 were both larger than PsCatCh2.0. The differences were statistically significant (t=7.10, 31.60; P=0.00, 0.00). In terms of response frequency, XXM2.0 and PsCatCh2.0 could follow to 32 Hz high-frequency pulsed light stimulation, and all could respond to repeated light stimulation at a long (4000 ms) and a short time (200 ms) interval with the small current decay rate.ConclusionXXM2.0 and PsCatCh2.0 could be activated under light intensity with safety for the retina, and could respond to high frequency (at least 32 Hz) pulsed light stimuli with low current attenuation, which could meet the characteristics of opsins required to restore the visual function by optogenetics.
ObjectiveTo explore the light response, retinal inflammation and apoptosis of the retinal ganglion cells (RGCs) 1 year after the new type of channelrhodopsin PsCatCh2.0 was transfected into the retina of rd1 mice. MethodsTwenty-four male rd1 mice were randomly divided into rd1 experimental group and rd1 control group, 12 mice in each group. 1.5 μl of recombinant adeno-associated virus (rAAV)2/2-cytomegalovirus (CMV)-PsCatCh2.0-enhanced green fluorescent protein (EGFP) was injected into the vitreous cavity 1 mm below the corneoscleral limbus of mice in the rd1 experimental group, and the same dose of recombinant virus was injected 2 weeks later at temporal side 1 mm below the corneoscleral limbus. One year after virus injection, the light response of RGCs expressing PsCatCh2.0 was recorded by patch clamp technique; the expression of PsCatCh2.0 in the retina was evaluated by immunofluorescence staining; the transfection efficiency of recombinant virus was evaluated by the transfection efficiency of virus and the number of RGCs. Hematoxylin-eosin staining was performed to measure the inner retinal thickness. Western blotting was used to detect the protein expression of nuclear factor (NF)-κB p65 in retina; real-time quantitative polymerase chain reaction was used to detect the relative expression of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and Bax mRNA. Terminal deoxynucleotidyl transferase kit was used to observe the apoptosis of retinal cells in each group of mice. ResultsOne year after the intravitreal injection of recombinant virus, PsCatCh2.0-expressing RGCs can still generate 30 pA photocurrent. The virus PsCatCh2.0-EGFP was mainly transfected into RGCs, and partly transfected into amacrine cells, almost no transfection was seen in bipolar and horizontal cells. There were no significant differences in the number of RGCs and thickness of the inner retina between the rd1 experimental group and the rd1 control group (F=14.35, 0.05; P＞0.05), while the rd1 experimental group NF-κB p65 protein expression, TNF-α and IL-6 mRNA quantification were significantly lower than those of rd1 control group (F=4.61, 5.91, 5.78; P＜0.05). The number of red fluorescent apoptotic cells in the retina of mice in the rd1 experimental group was less than that in the rd1 control group, and the Bax mRNA expression was lower than that in the rd1 control group, and the difference was statistically significant (F=7.52, P＜0.01). ConclusionOne year after intravitreal injection of recombinant virus, the PsCatCh2.0 expressing RGCs can still generate photocurrent. Long term transfection and expression of PsCatCh2.0 has no obvious cytotoxic effect on RGCs, nor it increases the inflammatory effect of the retina of rd1 mice with retinal degeneration.
PURPOSE: To explore the pathogenesis of anisometropic and amblyopias.
METHODS:To carry out on monocular and binocular atropinized cat models during the developmental period for anisometropia and ametropia ,and measure the cytosomal sectional area and some parameters of the dendric field from the dorsal lateral geniculate nuclei (dLGN)of adult cats by using Golgi-Cox
staining.
RESULIS:The changes of cytosomal sectional areas and parameters about dendric fields in the dLGN of experimental cats were as following:significant differences between cells of dLGN's A1 lamina by the monocular atropinized eyes and normal ones, binocular atropinized eyea and normal ones;no significant difference between tbat driven by the monoular and binocular atropinized eyes. CONCLUSIONS:There might be resemble pathogenesis between anisomelropic and ametropic amblyopias.
（Chin J Ocul Fundus Dis,1996,12:153-156）
ObjectiveTo evaluate the effectiveness and safety of the additional catheter-directed thrombolysis (CDT) and conventional treatment (CT) for treatment primary deep vein thrombosis.
MethodsDatabases such as CNKI, WanFang Data, Pubmed, EMBASE.com, Medline, CBM, CSJD, CJFD, and the Cochrane Library were electronically searched from the date of their establishment to 30 June, 2013, and the relevant literatures and conference proceedings were also manually searched to include randomized controlled trials (RCTs) on comparison of additional CDT versus CT for primary deep vein thrombosis. Two reviewers independently screened studies according to the inclusion and exclusion criteria, extracted data, and accessed the methodological quality of the included studies. Then the meta-analysis was performed by using RevMan 5.1 software. Publication bias was assessed by STATA software. A meta-regression model was used to describe between study variability.
ResultsTwo RCTs including 3 literatures contain 224 patients reporting data on safety and efficacy of CDT versus CT were included. There were no publication bias (Begg'S test, Z=1.02. P > 0.05;Egger'S test, t=0.98, P > 0.05). The results of meta-analysis showed that:in 6 months after surgery iliofemoral vein patency rate of CDT group was higher than that of CT group (OR=3.62, 95% CI:1.51-8.64, P=0.004), in 6 months after surgery CDT group with a lower rate than CT group of the iliofemoral vein occlusion and (or)venous reflux rate (OR=0.24, 95% CI:0.11-0.53, P=0.000), and the incidence rate of PTS in 24 months after surgery in CTD group was less than that of CT group (OR=0.55, 95% CI:0.31-0.96, P=0.040). There were no statistically significant of the major complications after surgery between CDT group and CT group (OR=1.34, 95% CI:0.12-15.69, P=0.810). But the incidence rates of minor complications and total complications after surgery in CT group were lower than those of CDT group (OR=13.67, 95% CI:4.08-45.83, P < 0.00 01 and OR=11.67, 95% CI:4.40-30.99, P < 0.000 01).
ConclusionsCDT is a effective and positive way to treat early deep venous thrombosis especially in terms of the patency of vascular and prevent the occlusion and PTS. Due to the limitation of the included studies, large sample size, multicenter, and high quality studies are needed to verify the above conclusion, such as the ATTRACT Study. The intracavitary therapy could be applied to clinic combining individual conditions of patients.
Objective To investigate the species distribution and antibiotic resistance of pathogens fromcatheter-related bloodstream infections ( CRBSI) in intensive care unit( ICU) , to provide evidence for the guidance of clinical rational administration.Methods A retrospective analysis was performed to review the microbiological and susceptibility test data of all CRBSI patients in ICU from January 2009 to December 2011. The patterns of antibiotic resistance among the top seven bacteria were compared. Results 67 cases of CRBSI were detected with 81 strains, including 40 Gram-positive ( G+ ) bacteria( 49.4% ) , 38 Gram-negative( G- ) bacteria ( 46.9% ) , and 3 fungi ( 3.7% ) . The main pathogens causing CRBSI were coagulase negative Staphylococci ( 27 strains, 33.3%) , Acinetobacter baumannii ( 12 strains, 14.8% ) , Klebsiella pneumoniae( 9 strains, 11. 1% ) , Staphylococcus aureus ( 8 strains, 9. 9% ) , Pseudomonas aeruginosa ( 7 strains, 8. 6% ) , Escherichia coli ( 6 strains, 7.4% ) , suggesting that Staphylococcus epidermidis was predominant pathogenic G+ bacteria, and Acinetobacter baumannii was predominant G- bacteria. The antibiotic resistance tests demonstrated that isolated G- bacillus was highly sensitive to carbopenem, while vancomycin-resistant G+ bacteria were not found. Conclusions Within the latest 3 years, the predominant pathogens of CRBSI in ICU are Staphylococcus epidermidis and Acinetobacter baumannii. Acinetobacter baumannii exhibited high drug resistance to all antibiotics.
ObjectiveTo explore etiopathogenesis of slow transit constipation(STC). MethodsThe model of rat with “cathartic colon” was established, and the changes of colonic electromyography of the rat was examined. ResultsThe frequency and amplitude of slow wave in vivo of rats with cathartic colon was decreased markedly. Postmeal spike potential and duration was decreased, showing that gastrocolonic reflex of rats colon was decreased.ConclusionLong term abuse of stimulant laxuatives could damage enteric nervous system and accelerate the pathological changes of STC.
ObjectiveTo investigate the changes of amount of interstitial cells of Cajal (ICC) and expression of stem cell factor (SCF)/c-Kit in the process of cathartic colon induced by emodin in mice.
MethodsA modified cathartic colon mouse model was established. Seventy-two healthy male Kunming (KM) mice were randomly divided into the blank control group and sustained drug delivery group.Morphological changes of colon in mice were observed; frozen section immunofluorescence was used to observed changes of amount of ICC; serum concentrations of SCF were examined by ELISA; Western blot was employed for observation of expression of SCF/c-Kit in colon.
ResultsAfter the mice model were completed, the weight of mouse, length and diameter of entire colon were all reduced compared with the blank control group. The amount of ICC appeared to decline in the beginning of the first 6 weeks with emodin used, and significant decreased in 10-12 weeks. The serum concentrations of SCF first began to decline in 4 weeks with emodin used, and significantly decreased in 6 weeks, and continued at a low level after 8 weeks. The expression of c-Kit in colon began to decline in 4 weeks with emodin used and significantly reduced after 8 weeks. Conciusions The amount of ICC appear to slowly decline in the beginning of the first 12 weeks with emodin used, and significant decrease after 12 weeks.The serum concentrations of SCF and expression of c-Kit in colon have the dynamic changes in the meanwhile, and the changes of SCF are earlier than that of c-Kit. The trend of amount ofICC may have a certain relationship with changes of SCF and c-Kit.
Objective To discuss the molecular structures and functions of βCatenin and APC (Adenomatous polyposis coli) genes, as well as the roles they played during the carcinogenesis and progression of tumors. MethodsAdvances in molecular biology and oncology of βCatenin and APC genes in recent years has been reviewed. ResultsHigh expression of βCatenin and APC genes was an early event during the carcinogenesis due to the abnormal regulation of βCatenin and APC genes. But on the contrary, the low expression of these two genes was probably associated with the progression of tumors. Moreover, βCatenin and APC genes could also regulate the expression of p53,cmyc genes and cyclin D1. Conclusion βCatenin and APC genes may play a key role during the carcinogenesis and progression of tumors and modulate other oncogen/suppressor gene and factors.
In existing vascular interventional surgical robots, it is difficult to accurately detect the delivery force of the catheter/guidewire at the slave side. Aiming to solve this problem, a real-time force detection system was designed for vascular interventional surgical (VIS) robots based on catheter push force. Firstly, the transfer process of catheter operating forces in the slave end of the interventional robot was analyzed and modeled, and the design principle of the catheter operating force detection system was obtained. Secondly, based on the principle of stress and strain, a torque sensor was designed and integrated into the internal transmission shaft of the slave end of the interventional robot, and a data acquisition and processing system was established. Thirdly, an ATI high-precision torque sensor was used to build the experimental platform, and the designed sensor was tested and calibrated. Finally, sensor test experiments under ideal static/dynamic conditions and simulated catheter delivery tests based on actual human computed tomography (CT) data and vascular model were carried out. The results showed that the average relative detection error of the designed sensor system was 1.26% under ideal static conditions and 1.38% under ideal dynamic stability conditions. The system can detect on-line catheter operation force at high precision, which is of great significance towards improving patient safety in interventional robotic surgery.
Objective To study the catheter-related infection (CRI) in cancer patients treated with central venous catheterization. Methods A prospective study with 196 cancer patients was conducted to analyze the types of catheter-related infection and pathogen, as well as the relationship between CRI and the following factors: insert location, gender, age, remained time, or bone marrow suppression. Results Of the total 196 cases, 16 cases were diagnosed as CRI and the CRI rate was 8.2%. The types of CRI were five cases of pathogen colonization, four cases of insert location infection and seven cases of catheter-related bloodstream infection. Of the total 244 specimens, 20 were positive including 7 pathogenic bacteria in either Gram positive or Gram negative types, the dominating pathogens were staphylococcus aureus, staphylococcus epidermidis, acinetobacter baumannii and klebsiella pneumoniae. CRI was related to both insert location and age which were both the independent risk factors. Conclusion The concept of prevention should be set up, and the comprehensive measures should be taken to reduce CRI, such as choosing an appropriate insert location and complying with a strict catheter insert standard.
