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The chigger mite Leptotrombidium sialkotense is one of the 6 main vectors of scrub typhus in China. Before present study, L. sialkotense was found in some parts of Hunan province, China with a narrow geographical distribution. During field investigation 2016-2017, we found L. sialkotense in Jingha, southern Yunnan, China. Of 15 small mammal host species, L. sialkotense were collected from 6 species of the hosts. Rattus brunneusculus was a dominant host of L. sialkotense, from which 98.3% of the mites were collected. The chigger mite showed a relatively high infestation prevalence (PM=11.7%) and mean abundance (MA=0.5) in comparison with the rest 5 host species. These results reveal a certain host specificity of L. sialkotense to a rat R. brunneusculus. The mite L. sialkotense showed an aggregated distribution on the host (P<0.05). A positive correlation observed between L. sialkotense and the body length of hosts. There was a positive interspecific association between L. sialkotense and 2 other dominant vectors, L. deliense and L. scutellare.
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Diabetic retinopathy (DR) is one of the leading causes of vision loss and can be effectively avoided by screening, early diagnosis and treatment. In order to increase the universality and efficiency of DR screening, many efforts have been invested in developing intelligent screening, and there have been great advances. In this paper, we survey DR screening from four perspectives: 1) public color fundus image datasets of DR; 2) DR classification and related lesion-extraction approaches; 3) existing computer-aided systems for DR screening; and 4) existing issues, challenges, and research trends. Our goal is to provide insights for future research directions on DR intelligent screening.
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BACKGROUND: Proximal humeral fracture is a common disease of fall injury in the elderly, because of bone nonunion after treatment with a variety of factors such as senile osteoporosis. Currently, the use of reverse total shoulder arthroplasty has achieved good clinical effect, but has certain limitations. OBJECTIVE: To compare and observe the clinical effects of reverse total shoulder arthroplasty and open reduction and internal plate fixation in the treatment of nonunion of proximal humeral fractures. METHODS: Totally 120 cases of nonunion of proximal humeral fractures were randomly divided into observation group and control group, with 60 cases in each group. The observation group received reverse total shoulder arthroplasty (replacement of artificial shoulder joint). The control group received open reduction and internal plate fixation. RESULTS AND CONCLUSION: (1) Follow-up results: At 3 years after surgery, the pain score was lower in the observation group than that in the control group (P < 0.05). Constant daily activities, range of activities, strength test score, Constant total score, satisfaction and hospitalization expenses were higher in the observation group than in the control group. Functions of flexion, laterotorsion and intorsion were better in the observation group than those in the control group (P < 0.05). (2) Adverse reactions: At 3 years after surgery, 26 and 22 cases had adverse reaction in the observation group and the control group respectively. (3) The results show that the clinical effect of the elders' nonunion of proximal humeral fracture treated with reverse total shoulder arthroplasty is quite good, and the pain degree and shoulder function are obviously improved. The curative effect of reverse total shoulder arthroplasty is better than that of open reduction and internal plate fixation.
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Aim To explore the effects of interleukin-1 receptor antagonist (IL-1Ra) on intestinal ischemia-reperfusion (I/R) induced injury in rats. Methods Thirty-five male SD rats were randomly divided into sham operation group (S), model group (I/R), dif-ferent dosage drug groups(C1,C2,C3). Rat intesti-nal I/R model was established via clamping the superi-or mesenteric artery (SMA). After 1 h of ischemia, the arterial clamps were released for 1 h of reperfusion. 10,20,50 mg·kg-1of IL-Ra was injected via caudal vein 15min before reperfusion. Results After 2 h of I/R,compared with S group,I/R group rats exhibited severe damage on the intestinal mucosa, increase in MDA content, decrease in SOD activity, and signifi-cant release of TNF-α, IL-1β, IL-6. The results showed that, following the injection of IL-1Ra after clipping superior mesenteric artery, damage of the in-testinal mucosa was obviously relieved in different dos-age drug groups. Furthermore, there was different de-gree of relief on oxidative stress and inflammatory re-sponses. Conclusion IL-1Ra showed obvious protec-tive effect on intestinal I/R induced injury by relieving oxidative stress and inflammatory response,and it may potentially be used in the clinical treatment of intestinal I/R injury.
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Objective To compare the regulation effects of different activated and inhibitory riboswitches , and to facilitate the precise regulation of gene circuits .Methods A green fluorescent protein amcyan expression vector regulated by different riboswitches (addA, M6, TPP and btuB) was constructed, and the expression level of amcyan under different ligand concentrations was analyzed by RT-qPCR and relative fluorescence intensity , and then compared with the expression level of a vector without any riboswitch .The dynamic control performance was analyzed .Results Under the control of addA and M6 activated riboswitches , the expression of green fluorescent protein increased with ligand concentrations , and addA riboswitch had more dynamic regulatory effect than M 6 riboswitch.However, under the control of TPP and btuB inhibitory riboswitches , the expression of green fluorescence decreased with the increase in ligand concentrations , and the dynamic regulation of btuB riboswitch was slightly greater than that of TPP riboswitch .Conclusion The regulation efficacy of different riboswitches which have the same mechanism varies .Activated riboswitch addA and inhibitory riboswitch btuB with dynamic regulation and control advantages are more suitable for precise metabolism regulation and target gene expression in Escherichia coli.
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Objective To develop chitosan composite keratinocyte growth factor-2 mutant(KGF-2M)temperature-sen-sitive dressing and evaluate its physicochemical properties and dynamic release rule were used.Methods Chitosan, chi-tosan quaternary ammonium salt,β-glycerophosphate and other adjuvant materials to configure different formulations which were compounded with KGF-2M in order to develop temperature-sensitive dressing.Gelling time, temperature,the release rate of KGF-2M and other indicators were measured to analyze the physical and chemical properties of the temperature -sen-sitive dressing.Results Chitosan-KGF-2M composite dressing with temperature-sensitive properties was obtained by opti-mizing the formulation components of chitosan and related adjuvant materials.When the liquid dressing was above 35℃,it could be converted from liquid to solid gelatin within 10 minutes.The compound KGF-2M released from the gel was more than 98%at 4 h,and its bioactivity remained stable.Conclusion The thermo-sensitive gel has the characteristics of good conformability,moisturizing(moisture),isolation,wound healing,and a controlled release effect,which has great potential in wartime for wound repair.
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Objective To infer its transmission origin and route through studying the feature of molecular epidemiology of an HCV outbreak in Guangzhou.Methods Serum samples 192 cases in an HCV outbreak incident were analyzed for 2a and 6a subtypes.Appropriate genotypes were selected as control group.Informatics software were used in the evolutionary analysis to construct time scale trees and infer the origin time of HCV infection.Results Of 119 patients in the HCV outbreak,66 cases were 2a and 110 cases were 6a subtype.No other genotypes were found.The evolutionary analysis indicated the isolates of 2a group and 6a group both originated from 2 ～ 5 years ago.Both of 2a group and 6a group were in line with the characteristics of iatrogenic infection.Conclusion 2a and 6a were the main sub-genotypes in the Guangdong HCV outbreak investigation and they were originated from 2 to 5 years ago,which were in line with the characteristics of iatrogenic transmission.With the extension of time,a large number of cases accumulated and led to outbreak.
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AIM To establish HPLC fingerprints of Zhihuang Tongfeng Decoction (Phellodendri chinensis Cortex,Anemarrhenae Rhizoma,Plantaginis Semen,etc.) and to determine the contents of four constituents.METHODS The analysis of aqueous extract of this drug was performed on a 30 ℃ thermostatic Wondasil C18 column (4.6 mm ×250 mm,5 μm),with the mobile phase comprising of acetonitrile-0.5％ acetic acid in a gradient elution manner,and the detection wavelength was set at 245 nm.RESULTS There were sixteen common peaks in the HPLC fingerprints of ten batches of samples with the similarities of more than 0.9.Berberine hydrochloride,mangiferin,geniposidic acid and salvianolic acid B showed good linear relationships within the ranges of 0.636 2-3.575 μg (R2 =0.9999),0.338-1.425 μg (R2 =0.9990),0.6452-2.7188 μg (R2 =1) and0.938 8-5.275 μg (R2 =0.999 3),whose average recoveries were 100.56％,98.35％,100.25％ and 102.11％ with the RSDs of 2.41％,1.17％,1.24％ and 2.02％,respectively.CONCLUSION This accurate,reliable and specific method can be used for the quality control of Zhihuang Tongfeng Decoction.
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AIM To establish HPLC fingerprints of Zhihuang Tongfeng Decoction (Phellodendri chinensis Cortex,Anemarrhenae Rhizoma,Plantaginis Semen,etc.) and to determine the contents of four constituents.METHODS The analysis of aqueous extract of this drug was performed on a 30 ℃ thermostatic Wondasil C18 column (4.6 mm ×250 mm,5 μm),with the mobile phase comprising of acetonitrile-0.5％ acetic acid in a gradient elution manner,and the detection wavelength was set at 245 nm.RESULTS There were sixteen common peaks in the HPLC fingerprints of ten batches of samples with the similarities of more than 0.9.Berberine hydrochloride,mangiferin,geniposidic acid and salvianolic acid B showed good linear relationships within the ranges of 0.636 2-3.575 μg (R2 =0.9999),0.338-1.425 μg (R2 =0.9990),0.6452-2.7188 μg (R2 =1) and0.938 8-5.275 μg (R2 =0.999 3),whose average recoveries were 100.56％,98.35％,100.25％ and 102.11％ with the RSDs of 2.41％,1.17％,1.24％ and 2.02％,respectively.CONCLUSION This accurate,reliable and specific method can be used for the quality control of Zhihuang Tongfeng Decoction.
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Objective:To explore the relationship between wearing of functional appliance and systemic metabolism of PGE2 in the blood of growing rats.Methods:54 male Wistar rats aged 4-weeks were randomly divided into 3 groups(n =18):Daytime group,all-day group and control group.Self-guided functional appliance was made for mandible advancement of the rats in the 2 experimental groups.One week after appliance wearing,rats were sacrificed at the corresponding time points and blood in femoral artery was taken. PGE2 levels in the blood samples were measured,data were analysed by cosine equation.Results:Hypothesis was true in the control group(P ＜0.05),and was not true in both 2 experimental groups(P >0.05).Conclusion:PGE2 level in rat blood is circadian rhyth-mic,wearing of functional appliance made may disturb the rhythm.
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This study was aimed to set up and evaluate a quantitative method for detecting lumbrokinase level in plasma. The lumbrokinase was used to immunize rabbit and BALB/c mouse for preparation of rabbit or mouse-derived polyclonal antibodies, and then the standard curves were drawn up by detecting the lumbrokinase diluted in PBS using the double antibody sandwich ELISA. This method further was analyzed for its specificity, precision and recovery rate. This established double antibody sandwich ELISA was used to assay the lumbrokinase in human plasma, and the assayed results were assessed. The results showed that a double antibody sandwich ELISA for the detection of lumbrokinase has been established. And the standard curve fitting R value > 0.99, the precision assessment showed that the measured values of coefficient of variation (CV) in 3 batches were all < 15%; recovery assessment in 3 batches showed that all the measured recovery rates were > 80%; the quantitative low limit was assessed as 5 ng/ml (precision CV < 15%, recovery rate > 85%). It is concluded that this method is consistent with the criteria stipulated by the Pharmacopeia, which provides a reliable measurement method for quantitative detection of plasma lumbrokinase in clinical trials.
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Animals , Humans , Mice , Rabbits , Endopeptidases , Blood , Enzyme-Linked Immunosorbent Assay , Methods , Mice, Inbred BALB C , PlasmaABSTRACT
This study was aimed to explore the influence of staphylokinase derivative (SAKD) on the hemoagglutinative and fibrinolytic systems, and to determine the safety of the staphylokinase derivative in application. The normal and model rats each 30 were divided into normal saline, SAKD and rSAK groups. The hemorrhage, bleeding time (BT), blood platelet count (BPC), activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), fibrinogen (Fg), D-dimer (D-D), plasminogen (PLG) and plasmin inhibitor activity (PI) were detected before and after the administration with staphylokinase derivative 0.5 mg/kg body weight, once three days for consecutive 15 days. The results indicated that one case of normal rats with SAKD and two cases of high fat diet model group had mild hemorrhage, all of which showed automatic hemostasis; and 3 cases in rSAK group had mild hemorrhage. And the platelet counting, D-D, PLG and PI in all groups did not significantly change. The rats of high fat diet group treated with SAKD showed the significant extension of APTT, PT and TT times, and the decrease of Fg time (p < 0.05). All the experimental results demonstrated that the influence of SAKD on the hemagglutination of the normal animals was lower, however, which can improve the high-hemagglutination status of the rats with high fat diet. It is concluded that the SAKD at the dosage of this study has the higher safety, which can alleviate the high hemagglutination symptoms of the rats with high fat diet.
Subject(s)
Animals , Male , Rats , Dietary Fats , Fibrin Fibrinogen Degradation Products , Fibrinolysis , Fibrinolytic Agents , Pharmacology , Hemagglutination , Hemostasis , Metalloendopeptidases , Pharmacology , Partial Thromboplastin Time , Platelet Count , Prothrombin Time , Rats, Wistar , Recombinant Fusion Proteins , Pharmacology , Thrombin Time , Thrombolytic TherapyABSTRACT
<p><b>OBJECTIVE</b>To study the method and effects of multi-stage manipulative reduction and homemade splint fixation in the treatment of tibia shaft fractures.</p><p><b>METHODS</b>Twenty-two patients (16 male and 6 female) were involved the retrospective study. The average age was 33 years (from 6 to 54 years). Single tibia shaft fracture was in 15 cases and tibiofibular fracture in 7 cases. Fracture site: 3 cases were in the upper part of the tibia, 4 in the middle part and 15 in the lower part. Fracture pattern: oblique fracture was in 8 cases, spiral fracture in 5 cases, comminuted fracture in 4 cases and transverse fracture in 5 cases. All the patients were treated with multi-stage manipulative reduction and homemade splint fixation.</p><p><b>RESULTS</b>All the patients were followed up from 3 to 15 months (mean 6 on months). There were malunion of fracture in 1 case, delayed union in 1 case and nonunion in 1 case. The results were excellent in 18 cases, good in 3 cases and poor in 1 case according to WANG Xu-dong assessment criteria.</p><p><b>CONCLUSION</b>On the base of traditional manipulative reduction and splint fixation, multi-stage manual correction could stabilize the broken part and prevent displacement. It had the characteristics of easy operation, reliable fixation, rapid union of fracture, few complications and influences on joint function. Multi-stage manipulative reduction and homemade splint fixation is one of the most reliable methods for closed tibia fracture.</p>
Subject(s)
Adolescent , Adult , Child , Female , Humans , Male , Middle Aged , Fracture Fixation , Fractures, Closed , General Surgery , Therapeutics , Musculoskeletal Manipulations , Retrospective Studies , Splints , Tibial Fractures , General Surgery , TherapeuticsABSTRACT
BACKGROUND: Fixation of bone fracture is one of the fundamental methods for bone fracture healing. The technique of AO has a lot of defects, such as negative effect induced by "stress dodging". Recently, the technique of CO is praised highly by national and international scholars. OBJECTIVE: To observe the influence of external fixation of small splint on healing of long bone fracture of rabbit, and compare to the internal fixation of steel plate.DESIGN: Randomized and controlled animal trial. SETTING: Research Institute of Orthopedics, Hubei College of Traditional Chinese Medicine.MATERIALS: The experiment was performed at the Laboratory of Orthopedics, Hubei College of Traditional Chinese Medicine from April 2006 to April 2007. Thirty rabbits were randomly divided into small splint fixation group and steel plate fixation group with 15 rabbits in each group. Small splint was self-made of fir-barks with good elasticity, and composed of exterior, interior, front and back splints. The upper part of the splint was wide and the lower part was narrow. We sting an eyelet in the small splint that is used in front and behind part. A hole was drilled in the front and back splints close to the tubercle of tibia. Steel plate was provided by Jiangsu Golden Deer Group (Type HA2.0). METHODS: The standard models of transverse fracture of 3 mm in the meta-infer 1/3 of left tibia were established. In small splint fixation group (SSF group), the fracture was fixed by plaster stone, and 5 days later, replaced by external fixation of small splint. The steel fixation group (SF group) was fixed by steel plate with 4 holes. Animals were executed 14, 24, and 34 days after surgery, respectively. The growth condition of bony callus in fracture sites was observed, and the histomorphology of bony callus and bone cell production during fracture healing was observed. MAIN OUTCOME MEASURES: Macroscopic observation of rabbit tibial bony callus, and histomorphology of bony callus and bone cell formation. RESULTS: In SSF group, the bony callus formed early, and there were plentiful and active osteoblast. Thirty-four days after surgery, bony union was observed in fracture sites. In SF group, there was little fibrous bony callus in the fracture ends 14 days after surgery, accompanied by granulation tissue. Twenty-four days after surgery, sparing cartilage synostosis was observed. On day 34 days, bony callus span the fracture ends, but fracture ends did not connect completely yet. Compared with the SF group, the quantity of bony callus and the speed of fracture healing were superior in SSF group. CONCLUSION: The external fixation of small splint can promote osteoblastic differentiation and proliferation, absorption of hematoma, calcification of the bony callus, and the growth and rebuilding of bone trabecula.
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This study was aimed to construct the soluble HLA-A*0201-PR1 complex for preparation of HLA-A*0201-PR1 tetramer. The recombinant HLA-A*0201-BSP (BirA substrate peptide) fusion protein as heavy chain and beta(2)-microglobulin (beta(2) m) as light chain were expressed highly as insoluble aggregates in Escherichia coli and then purified with gel filtration, and the final purity reached above 90%. The two subunits were refolded to form an HLA-A*0201-peptide complex by dilution method in the presence of an antigenic peptide PR1, a HLA-A2-restricted peptide from proteinase 3 (aa 169 - 177, VLQELNVTV). Refolded HLA-A*0201-PR1 complex was biotinylated using a BirA enzyme and purified by anion exchange chromatography on a Q-Sepharose (fast flow) column. The extent of reconstitution of the HLA-A*0201-PR1 complex was analyzed by HPLC gel filtration. The refolded and biotinylated products were detected by Western blot and ELISA with monoclonal antibody BB7.2 that recognized the natural conformations of HLA-A2 and streptavidin. The results showed that the refolded complex was composed of HLA-A*0201-BSP aggregate, HLA-A*0201-PR1 complex and beta(2) m, and reconstitution yields of 18% with PR1 was obtained. Refolded HLA-A*0201-PR1 complex could be confirmed by practical immunological method and biotinylated efficiently. It is concluded that the refolding and biotinylation of HLA-A*0201-PR1 complex is successfully obtained. This work provides the basis for the preparation of HLA-A*0201-PR1 tetramer.
Subject(s)
Humans , DNA Primers , Genetics , Escherichia coli , Genetics , HLA-A Antigens , Genetics , HLA-A2 Antigen , Oligopeptides , Genetics , Metabolism , Protein Binding , Protein Folding , Recombinant Fusion Proteins , beta 2-Microglobulin , Chemistry , GeneticsABSTRACT
cDNA for Insulin-like growth factor binding protein 3 was cloned and constructed a prokaryotic expression vector--pET-DsBA-IGFBP3. The construct was transformed into E. coli BL21 (DE3)plysS. The induced fusion protein (D-IGFBP3) was expressed successfully in soluble form. We obtained D-IGFBP3 the purify of which is over 95% after purification by His affinity chromatography. The product was identified by Western-blot. The cell assay showed that the obtained fusion protein can inhibit the growth of MCF-7 and bind with IGF-I in vitro.
Subject(s)
Humans , Blotting, Western , Cell Line, Tumor , Cell Proliferation , Chromatography, Affinity , Dose-Response Relationship, Drug , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Escherichia coli , Genetics , Gene Expression , Insulin-Like Growth Factor Binding Protein 3 , Genetics , Metabolism , Pharmacology , Insulin-Like Growth Factor I , Metabolism , Protein Binding , Recombinant Proteins , Metabolism , Pharmacology , SolubilityABSTRACT
Human beta(2)-microglobulin (beta(2)m) is the light chain of major histocompatibility complex (MHC) class I molecule. High-yield production of this protein is a prerequisite to the preparation of MHC class I tetramer. The present study was aimed to obtain recombinant human beta(2)m expressed in Escherichia coli (E. coli) for preparing MHC class I tetramers. For cloning of human beta(2)m gene, a pair of specific primers was designed based on the published sequence of this gene. A 300 bp specific DNA fragment corresponding to the encoding region of beta(2)m lack of the signal peptide sequence was obtained by RT-PCR from the total RNA of human leukocytes. The amplified cDNA was inserted into the IPTG-inducible expression plasmid pET-17b by Nde I and Bam H I sites and its sequence was confirmed by DNA sequence analysis. The recombinant plasmid pET-beta(2)m was transformed to the competent cells of E. coli BL21 (DE3). The results showed that beta(2)m was expressed in the form of inclusion body and amounted to over 32% of total cell proteins after IPTG induction. After washing with triton X-100 and urea, the inclusion body was dissolved with 4 mol/L urea and then purified with Sephacryl S-200 HR, and the final purity reached above 95%. The denatured protein was renatured by dilution method. Western blot assay indicated that the monoclonal antibody against human native beta(2)m could react specifically with the recombinant protein. In conclusion, the human beta(2)m gene was cloned successfully and expressed efficiently in E. coli BL21 (DE3). This work establishes a convenient approach for renaturation and purification of large quantity of recombinant beta(2)m. This provides the basis for the preparation of MHC tetramers.
Subject(s)
Humans , Cloning, Molecular , Escherichia coli , Genetics , Gene Expression , Histocompatibility Antigens Class I , Genetics , Recombinant Proteins , beta 2-Microglobulin , GeneticsABSTRACT
High-yield production of HLA-A*0201 heavy chain is a prerequisite to the preparation of HLA-A2 tetramer. The present study was aimed to construct the expression vector of recombinant HLA-A*0201-BSP fusion gene for preparing HLA-A2 tetramers. The extracellular region HLA*0201 was cloned by RT-PCR from HLA-A2(+) donor, and a 15-amino acid biotin-protein ligase (BirA) substrate peptide (BSP) for BirA-dependent biotinylation was added to the COOH-terminus of HLA-A*0201 heavy chain. Then the fusion gene was cloned into pBV220 vector at EcoRI and Bam HI sites and its sequence was confirmed by DNA sequence analysis. The recombinant plasmid pBV220-HLA-A*0201-BSP was transformed to the competent cells of E.coli DH5alpha. The results showed that the HLA-A*0201-BSP fusion protein was successfully expressed in the form of inclusion body and amounted to over 28% of total cell proteins via induction at 42 degrees C. After washed with triton X-100 and urea, the inclusion body was dissolved with 8 mol/L urea and then purified with Sepharcyl S-300 HR, and the final purity reached above 90%. It is concluded that the HLA-A*0201-BSP fusion gene was cloned successfully and expressed efficiently in E.coli DH5alpha. This work establishes a convenient approach for purification of large quantity of recombinant HLA-A*0201-BSP. This provides the basis for the preparation of HLA-A2 tetramers.