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1.
Int J Biol Macromol ; 279(Pt 3): 135255, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39236965

RESUMEN

A polysaccharide, CZS-0-1, was obtained from the marine green algae Codium fragile using ion-exchange and size-exclusion chromatography. Composition and characteristics analyses showed CZS-0-1 was a sulfated galactoarabinan consisting of arabinose, galactose and a small amount of glucose in a ratio of 9:2:1 with 21% sulfate content and a molecular weight of 810 kDa. Structural properties were determined using desulfation and methylation analyses combined with instrument analysis. The results showed that the backbone of CZS-0-1 was (1 â†’ 3)-ß-L-Arap. Its O-4 and/or O-2 positions showed sulfate modification; additionally, it had 10% of (1 â†’ 3)-ß-D-Galp branches at the O-4 position of the (1 â†’ 3)-ß-L-Arap. The galactose side chains also had sulfate modification at the O-4 or O-6 position. The structure of CZS-0-1 was further confirmed by Top-down analysis of the oligosaccharides after oxidated hydrolysis by mass spectrometry. CZS-0-1 exhibited significant heparin-like anticoagulant activity. It exerted anticoagulant effects by inhibiting FIIa and FXa activities with the presence of heparin cofactors. The anticoagulant activity of CSZ-0-1 was closely related to the molecular weight, and the reduction of molecular weight may lead to a significant decrease in the anticoagulant activity. This study demonstrated that the green algae, Codium fragile can be considered as a useful resource for bioactive polysaccharides.


Asunto(s)
Anticoagulantes , Chlorophyta , Oligosacáridos , Chlorophyta/química , Anticoagulantes/farmacología , Anticoagulantes/química , Anticoagulantes/aislamiento & purificación , Oligosacáridos/química , Oligosacáridos/farmacología , Oligosacáridos/aislamiento & purificación , Polisacáridos/química , Polisacáridos/farmacología , Polisacáridos/aislamiento & purificación , Peso Molecular , Sulfatos/química , Galactosa/química , Metilación
2.
STOMATOLOGY ; (12): 197-203, 2023.
Artículo en Zh | WPRIM | ID: wpr-979342

RESUMEN

Objective@#To investigate the effects of fiber surface deposited with silicon dioxide films by atomic layer deposition on properties of dental fiber-reinforced composites.@*Methods @#SiO2 films were deposited on the surface of quartz fiber by atomic layer deposition(ALD). Then the quartz fiber was used to manufacture fiber resin composites, which were divided into four groups: A(no soaking agent removal), B(soaking agent removed), C(soaking agent removed and silanization), and D(soaking agent removed, 600 ALD cycles performed and then silanization). Scanning electron microscopy, water contact angle test, hygroscopicity test, CCK8 test and three-point bending test were used to investigate the properties of fiber resin composites.@*Results@#The surface morphology of the quartz fiber treated by ALD was smooth and had no obvious change compared with that before treatment. Moreover, the quartz fiber showed hydrophobicity after silanization. The results of three-point bending test revealed that the mechanical properties of fiber-resin composites modified by ALD were significantly improved(P<0.05). When viewed by scanning electron microscopy, a good interfacial bonding could be seen between quartz fibers and the resin matrix in Group D. In addition, it was found that Group D had low absorbability, low solubility and good biocompatibility. @*Conclusion@#It is shown that deposition of SiO2 films on the quartz fiber by ALD can significantly enhance the mechanical properties of fiber-reinforced composites.

3.
Artículo en Zh | WPRIM | ID: wpr-996083

RESUMEN

Objective:To analyze the influencing factors of the medical insurance balance of hospitalization expenses for gastric cancer surgery patients under DRG payment, for reference for promoting the reform of DRG payment in public hospitals and controlling hospitalization expenses reasonably.Methods:The gastric cancer patients enrolled in the gastroenterology department of a tertiary comprehensive hospital from January to July 2022 were selected as the research subjects. The indicators such as patient age, medical insurance balance, hospitalization expenses and their composition were extracted from the hospital information management system and the medical insurance settlement system a certain city. Descriptive analysis was conducted for all data, and stepwise multiple linear regression was used to analyze the influencing factors of patients′ medical insurance balance. Monte Carlo simulation method was used to simulate different combination scenarios of various influencing factors to analyze the probability of medical insurance balance.Results:A total of 205 patients were contained, including 117 in the medical insurance balance group and 88 in the loss group. The difference in hospitalization expenses and medical insurance balance between the two groups of patients were statistically significant ( P<0.05). The intervention of medical insurance specialists, correct DRG enrollment, parenteral nutrition preparation costs, anti infective drug costs, examination costs, and consumables costs were the influencing factors of patient medical insurance balance ( P<0.05). Through Monte Carlo simulation verification, patients with different cost parenteral nutrition preparations, or different anti infective drug schemes had the higher probability of medical insurance balance in the scenario where the medical insurance commissioner intervenes and the DRG enrollment was correct. Conclusions:The hospital adopted interventions from medical insurance specialists to ensure the correct DRG enrollment of patients, accurate use of parenteral nutrition and anti infective drugs, and reasonable control the cost of examinations and consumables, which could increase the probability of medical insurance balance for gastric cancer surgery patients. In the future, hospitals should further promote the procurement of drug consumables in bulk, reduce unnecessary examinations, develop standardized perioperative nutritional interventions and anti infection treatment pathways, ensure the accuracy of DRG enrollment, optimize clinical diagnosis and treatment pathways to improve the efficiency of medical insurance fund utilization and provide high-quality medical services for patients.

4.
Artículo en Zh | WPRIM | ID: wpr-960719

RESUMEN

Background The increasing threats of air pollution and extreme weather have been widely recognized in recent years in China, but their individual and joint effects on cardio-cerebrovascular mortality are unclear. Objective This study aims to investigate the individual effects of and potential interactions between oxidant pollutants and ambient temperature on cardio-cerebrovascular mortality risks. Methods We collected daily data on death counts of cardio-cerebrovascular diseases, concentrations of ambient air pollutants, and meteorological parameters in Guangzhou, Chinabetween 1 January 2006 and 31 December 2016. A generalized additive model with a Poisson distribution was conducted to assess the associations of oxidant pollutants and ambient temperature with cardio-cerebrovascular mortality risks. Bivariate response surface models and stratified analyses were further adopted to qualitatively and quantitatively examine the potential interactions between oxidant pollutants and ambient temperature on cardio-cerebrovascular mortality risks. Results During the study period, the daily averages were 60.3 μg·m−3 for ozone (O3), 50.9 μg·m−3 for combined atmospheric oxidant capacity (Ox), 32.5 μg·m−3 for nitrogen dioxide (NO2), and 22.3℃ for ambient temperature. The average daily death counts of coronary and stroke diseases were 20 and 15, respectively. Per 10 μg·m−3 increment in O3, Ox, and NO2 were associated with increased coronary mortality risks (excess risk, ER) of 1.26% (95%CI: 0.79%-1.74%), 1.61% (95%CI: 0.99%-2.23%), and 1.33% (95%CI: 0.59%-2.07%), and with increased stroke mortality risks of 1.56% (95%CI: 1.04%-2.09%), 2.30% (95%CI: 1.60%-3.01%), and 2.93% (95%CI: 2.07%-3.79%) over cumulative lags of 2-5 days, respectively. The exposure-response relationships between ambient temperature and coronary and stroke mortality risks exhibited an inverse "J" shape, with the minimum mortality at temperatures of 25.7℃ for coronary disease and 27.3℃ for stroke. Our results further showed potentially synergic effects of higher temperatures and higher levels of O3 and Ox exposures on coronary mortality risks, and the relative ER due to interactions was 0.103 (95%CI: 0.028-0.178) for O3 and 0.079 (95%CI: 0.004-0.154) for Ox. We didn't find evidence of an interaction between oxidant pollutants and low temperature. Conclusion Short-term exposures to oxidant pollutants are associated with increased cardio-cerebrovascular mortality risks, and the interactive effects of high temperature and oxidant pollutants are synergistic in relation to cardio-cerebrovascular mortality risks.

5.
China Pharmacy ; (12): 2119-2124, 2020.
Artículo en Zh | WPRIM | ID: wpr-825192

RESUMEN

OBJECTIVE:To investigate the effects of curcumin on bone metabolism balance in ovariectomized osteoporosis model rats ,and to investigate its potential mechanism. METHODS :Totally female Wistar rats were randomly divided into blank group(group A ),model group (group B ),estradiol group [group C (positive control ),estradiol valerate 50 μg(/ kg·d)], curcumin low-dose ,medium-dose and high-dose groups [group D-F ,55,110,165 μg(/ kg·d)],with 15 rats in each group. Except for group A ,other rats were ovariectomized to establish osteoporosis model. After modeling ,group A and B were given normal saline intrgastrically ,and administration groups were given relevant medicine intrgastrically 30 mL/kg,once a day ,for consecutive 12 weeks. The contents of serum bone metabolism markers [BALP ,CBF-α1,CTX-Ⅰ,PINP and OC] were determined by ELISA. The bone mineral density (BMD)and trabecular structure indexes [relative bone volume fraction (BV/TV),trabecular number (Tb.N),trabecular thickness (Tb.Th),connectivity density (Conn. D ),trabecular separation (Tb.Sp)and structure model index (SMI)] were determined by micro CT imaging system. The mRNA and protein expression of OPG and RANKL in hypothalamus and femur were determined by RT-PCR and Western blotting assay. RESULTS :Compared with group A ,the contents of serum bone metabolism markers ,BMD,BV/TV,Tb.N,Tb.Th,Conn.D,mRNA and protein expression of OPG were decreased significantly in group B ,while Tb.Sp ,SMI,mRNA and protein expression of RANKL were increased significantly @qq.com (P<0.05). Compared with group B ,the contents of serum bone metabolism markers ,BMD,BV/TV,Tb.N,Tb.Th,Conn.D,mRNA and protein expression of OPG were increased significantly in administration groups ;Tb.Sp,SMI,mRNA and protein expression of RANKL were decreased significantly ,in a dose-dependent manner among curcumin groups (P<0.05 or P<0.01). CONCLUSIONS :Curcumin can improve the level of bone metabolism,increase BMD ,improve the trabecular microstructure and inhibit bone absorption in ovariectomized osteoporosis model rats. Its mechanism may be related to the regulation of OPG/RANKL signaling pathway.

6.
Artículo en Zh | WPRIM | ID: wpr-613691

RESUMEN

Objective To investigate effects of physical exercise (PE) on object recognition memory in adult rats of postnatal isoflurane (Iso) exposures.Methods One hundred and ten postnatal 7-day SD rats (P7) were randomly divided into four groups: normal control group (Naive), Naive+PE group (received physical exercise in P21: a treadmill exercise 30min each day, 5 times/week, for 6 weeks), Iso group (three times of 2-hour Iso exposure in P7, P9, and P11), and Iso+PE group (received PE in P21 after postnatal Iso exposures). In P67, behavioral testing was conducted including open field and object recognition task (ORT), recording the time (Discrimination Ratios, DR) that rats spent on exploring each object, evaluating effects of PE on object recognition memory.Results There was no significant difference in influence of PE on open field testing in all of the groups (P>0.05). Compared with Naive, there was no group difference in DR (P>0.05) for all groups, but the DR of Iso male rats was significantly higher than that of Naive female rats in P67, with significant difference (P=0.034). Compared with non-PE groups, whether or not postnatal Iso exposures, the DR of PE male groups was significantly higher (compared with Naive and Iso group:P67,P=0.050,P=0.017; P95,P=0.037,P=0.019); in female rats, the DR for ISO+PE group was lower than that of Iso group in P67 (P=0.036), but the DR of Naive+PE group was higher than that of Naive group in P95 (P=0.004). Compared with male rats, the DR of non-PE female rats was significantly higher in P67 (vis. Naive and Iso group:P=0.022,P=0.011); but in P95, the DR of non-Iso female groups was significantly higher than that of male groups (vis. Naive and Naive+PE:P=0.008,P=0.017).Conclusions There is no obvious impact of postnatal Iso exposures on object recognition memory of adult rats. These Results also indicate that postnatal PE could improve object recognition memory of non-spatial learning in adult rats. In addition, exercise benefits have gender differences.

7.
Artículo en Zh | WPRIM | ID: wpr-619370

RESUMEN

Objective To investigate the potential effect of glucagon-like peptide-1 (GLP-1) analogue exendin-4 (Ex-4) on immune function of T lymphocytes via neuroendocrine modulation mechanism in mice following severe burns.Methods Male BALB/C mice were randomly (ramdam number) divided into thermal injury group (n =50) and sham-thermal group (n =30).The thermal injury model was made by exposing the back skin of 15% total body surface area (TBSA) to 95 ℃ water for 7 seconds,while in sham-thermal model the mice were immersed in 37 ℃ water instead.The expression of GLP-1 receptor (GLP-1 R) was determined in sorted CM + T cells from normal mice by immunofluorescence method.In ex vivo experiment,the mice were sacrificed at 24 h post-bum,then the mononuclear cells (MNC) from spleen were separated from both groups and cultured in RMPI 1640 with 10% FCS (fetal calf serum) in presence of ConA (concanavalin A,5 μg/mL).Cells were pretreated with catecholamine receptor antagonist propranolol (prop) for 1 hour,followed by consecutive dose of Ex-4 for another 48 h.In in vivo experiment,prop (30 mg/kg) was i.p.injected 30 minutes before thermal injury,then Ex-4 (2.4 nmol/kg) was injected i.p.immediately after scalding.Mice were sacrificed at 6 h and 24 h after thermal injury,then the serum and the spleens were collected.Results GLP-1R was expressed on splenic CD4 + T cells from normal micc.Ex-4 exerted no marked effect on the functions of T cells in terms of proliferation and IL-2 secretion at all doses examined ex vivo,which was not affected by pretreatment with prop.In vivo,T cell functions were suppressed by Ex-4 in thermal mice (P < 0.05),but was restored by pretreatment with prop.Regardless of ex vivo or in vivo,Ex-4 could induce T cells switched to Th2 response (P < 0.05).Moreover,the Th2 switch by Ex-4 was greatly potentiated by prop intervention in thermal mice in vivo other than ex vivo.Norepinephrine level was increased and epinephrine was decreased by Ex-4 in thermal mice.Both norepinephrine and epinephrine levels were obviously enhanced by pretreatment with prop.Conclusions Ex-4 can inhibit the proliferation and IL-2 secretion of splenic T lymphocytes through the sympathetic nervous system,however,it might induce Th2 switch from Th cells by acting directly on GLP-1R.

8.
Chinese Journal of Burns ; (6): 77-81, 2016.
Artículo en Zh | WPRIM | ID: wpr-327368

RESUMEN

<p><b>OBJECTIVE</b>To investigate the changes in plasma gelsolin (pGSN) levels in severe burn patients with sepsis, and to evaluate the prognosis of patients when combined with other related clinical indexes.</p><p><b>METHODS</b>Sixty-five severe burn patients with sepsis hospitalized from June 2013 to June 2015 conforming to the study criteria were divided into death group (n=24) and survival group (n=41) according to the clinical outcome on post sepsis diagnosis day (PSD) 28. The pGSN levels of patients were determined on PSD 1, 3, 7, and 14 with double antibody sandwich enzyme-linked immunosorbent assay. The serum level of C-reactive protein (CRP), serum level of procalcitonin, lactate level of arterial blood, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and Sequential Organ Failure Assessment (SOFA) score were determined or recorded on PSD 1. Data were processed with repeated measurement analysis of variance, t test, and chi-square test. On PSD 1, the pGSN level, serum level of CRP, serum level of procalcitonin, lactate level of arterial blood, APACHE II score, and SOFA score of 65 patients were collected to screen the independent risk factors related to death with single factor and multi-factor Logistic regression analysis. Receiver operating characteristic (ROC) curves of the independent risk factors related to death were plotted to evaluate the predictive power for death in 65 patients.</p><p><b>RESULTS</b>(1) The pGSN levels of patients in death group on PSD 1, 3, 7, and 14 were respectively (146±44), (85±24), (28±7), and (19±4) mg/L, obviously lower than those in survival group [(287±82), (179±51), (196±56), and (249±67) mg/L, with t values from 1.735 to 4.304, P<0.05 or P<0.01]. (2) The serum level of CRP, serum level of procalcitonin, lactate level of arterial blood, APACHE II score, and SOFA score of patients in death group on PSD 1 were respectively (56±7) mg/L, (12.54±0.82) μg/L, (2.74±0.27) mmol/L, (24.3±2.4) points, and (11.43±0.57) points, significantly higher than those in survival group [(35±4) mg/L, (2.38±0.16) μg/L, (1.83±0.12) mmol/L, (15.0±1.5) points, and (7.22±0.23) points, with t values from 1.902 to 3.883, P<0.05 or P<0.01]. (3) Multi-factor Logistic regression analysis showed that the pGSN level (odds ratio: 6.83, 95% confidence interval: 4.33-10.25, P<0.01) and APACHE II score (odds ratio: 5.27, 95% confidence interval: 2.28-9.16, P<0.01) were the independent risk factors related to death in 65 patients on PSD 1. (4) The total areas under the ROC curves of pGSN level and APACHE II score for predicting death of 65 patients on PSD 1 were respectively 0.89 and 0.86, and 142 mg/L and 21 points were respectively chosen as the optimal threshold values, with sensitivity of 87% and 83% and specificity of 86% and 89%.</p><p><b>CONCLUSIONS</b>For severe burn patients with sepsis, lowering of pGSN level and elevation of APACHE II score are obviously correlated with increase in case fatality rates. Monitoring the dynamic changes in pGSN level and APACHE II score during the early stage may be useful to predict the prognosis of severe burn patients with sepsis.</p>


Asunto(s)
Humanos , Quemaduras , Proteína C-Reactiva , Calcitonina , Sangre , Péptido Relacionado con Gen de Calcitonina , Ensayo de Inmunoadsorción Enzimática , Gelsolina , Sangre , Hospitalización , Puntuaciones en la Disfunción de Órganos , Pronóstico , Precursores de Proteínas , Sangre , Curva ROC , Análisis de Regresión , Factores de Riesgo , Sepsis , Sangre , Diagnóstico , Índice de Severidad de la Enfermedad
9.
Chinese Critical Care Medicine ; (12): 267-271, 2016.
Artículo en Zh | WPRIM | ID: wpr-487291

RESUMEN

Objective To investigate effects of isoflurane anesthesia of different time interval on acute injury of brain function in neonatal rats with consistent total time of isoflurane anesthesia. Methods Seven-day neonatal Sprague-Dawley (SD) rats were randomly divided into normal control group (breathe the air), continuous anesthesia group (a single 6-hour exposure to 1.5% isoflurane), and intermittent anesthesia 1 day and 3 days groups (three times of 2-hour exposure to anesthesia with an interval of 1 day or 3 days), 12 rats in each group. The ratio of male to female was 5:7. They underwent the test of learning and memory in the radial arm maze (RAM) 21 days after birth, twice a day for 4 days. The number of entry into wrong arms, number of repeated errors, number of total arm entries, and time for completing the task were recorded for evaluation of effect of neonatal isoflurane on cognitive behavior in rats. Results ① Compared with normal control group, the percentage of number of errors > 3 in anesthesia of 3-day interval group was significantly decreased (33.3% vs. 46.9%, P 0 and total arm entries > 8 were significantly increased (33.3% vs. 18.8%, 27.1% vs. 13.5%, both P 3 between continuous anesthesia group, interval anesthesia 1-day group and the normal control group (44.8%, 44.8% vs. 46.9%), the percentages of number of repeated mistake > 0 and total arm entries > 8 in above three groups were slightly increased as compared with those of normal control group (27.1%, 22.9% vs. 18.8%, 20.8%, 21.9% vs. 13.5%, all P > 0.05). No statistical differences in completing the task among normal control group, continuous anesthesia group, interval anesthesia 1 day and 3 days groups were found (minutes: 1.32±0.91, 1.54±1.05, 1.46±0.86, 1.38±0.79, all P > 0.05). ② It was found by gender analysis that the percentages number of repeated errors > 0 and total arm entries > 8 were significantly lower in female rats than those in the male rats only in normal control group (5.0% vs. 28.6%, P 0 in continuous anesthesia group, interval anesthesia 1 day and 3 days groups (25.0%, 25.0%, 30.0% vs. 5.0%, P 8 in interval anesthesia 1 day and 3 days groups were significantly higher than that of normal control group (22.5%, 25.0% vs. 5.0%, both P < 0.05). No significant difference about the RAM task in male rats of all the four groups was found. Conclusions Different time interval of neonatal isoflurane exposure may develop certain degree of acute brain injury in rats, characterized by cognitive function. Prolongation of the interval time significantly enhanced long-term memory in rats. Multiple neonatal exposures to isoflurane were associated with greater cognitive impairment than a single exposure. In addition, isoflurane can significantly increase cognitional functional disorder in the female, not in the male rats.

10.
Artículo en Zh | WPRIM | ID: wpr-436479

RESUMEN

Objective To evaluate the efficacy and safety of induction chemotherapy and three-dimensional conformal radiation (3D-CRT) combined with endostar in the treatment of locally advanced non-small cell lung cancer (NSCLC).Methods Thirty patients with locally advanced NSCLC were enrolled and divided into observation group (15 cases) and control group (15 cases).In the observation group,the patients received induction chemotherapy and 3D-CRT combined with endostar.Chemotherapy:Vinorelbine 25mg/m2 on day 1 and 8,DDP 30mg/m2 on day 2 to 4.Endostar 7.5mg/m2 on day 1 to 14,which was used again after 7 days for 2 to 4 cycles.In the control group,the patients received induction chemotherapy and 3D-CRT at the same dosage.All patients were treated with 3D-CRT and the prescription dose was 60 ~ 68Gy per fraction.The responses were evaluated according to WHO criteria.The shortterm efficacy between the 2 groups was compared.Results The overall effective rate of the two groups were 66.7% and 60.0%,respectively (P > 0.05).The median progression-free survival time was 12 months in the observation group and 10 months in the control group.The median survival time was 20 months in the observation group and 18 months in the control group.The 1 year overall survival rate was 80.0% in the observation group and 73.3% in the control group(P > 0.05).The main toxicities in the two groups were marrow suppression,gastrointestinal symptoms,acute radiation pneumonitis and acute radiation esophagitis.There was no significant difference between the two groups (P > 0.05).Conclusions The combination of endostar with induction chemotherapy and 3D-CRT can improve the short-term efficacy rate of locally advanced NSCLC,the adverse events of which are tolerable,but the improvement is not significant in both groups.The result pending further randomized multi-center phase Ⅲ clinical study.

11.
Artículo en Zh | WPRIM | ID: wpr-415955

RESUMEN

Objective To study in targeted therapy of cancer drug endostar combined with radiotherapy and chemotherapy in the treatment of newly diagnosed patients with advanced non-small cell lung cancer, and find an effective combined treatment mode of advanced non-small cell lung cancer, so as to improve the survival rate and quality of life of patients with advanced lung cancer. Methods 18 patients with newly diagnosed advanced non- small cell lung cancer admitted to our hospital from July 2009 to February 2010 were randomly divided into 2 groups and treated with induction chemotherapy and 3D-CRT,9 cases in the experimental group (including Endostar), 9 cases in the control group, All of the patients'clinical symptoms, efficacy and toxicity in the two groups were observed. At the same time, nursing of radiotherapy, chemotherapy and targeted therapy was given to paients. Results The efficacy of the experimental group and the control group were 77.8% and 66.7%, the clinical remission rates of the experimental group and the control group showed no significant difference, both of the patients in the two groups had varying degrees of toxicity, but all of the them completed the treatment well under the holistic nursing and systematical health education by nurses. Conclusions Endostar combined with induction chemotherapy and three-dimensional conformal radiotherapy (3D-CRT) in the treatment of advanced non-small cell lung cancer can improve the efficacy and survival rate, and the quality of life, although there are some side effects, but can be alleviated by symptomatic treatment and care.

12.
Journal of Geriatric Cardiology ; (12): 249-254, 2009.
Artículo en Zh | WPRIM | ID: wpr-472131

RESUMEN

Abstract Sepsis and related syndromes are the major cause of multiple organ failure and death in patients with critical illnesses.Neuroendocrine dysfunction has long been thought to be an important event in sepsis.In clinic,optimal management of the hormones could alleviate severe complications in sepsis.In this article,we review the dysfunction of neuroendocrine system as well as autonomic nervous system in sepsis,and summarize the respective therapy strategies.

13.
Artículo en Zh | WPRIM | ID: wpr-408298

RESUMEN

BACKGROUND: Polymethylmethacrylate (PMMA) can ameliorate the condition between vertebral pedicle screws and peripheral bone-matrix interfaces and notably enhance the strength of screw fixation. However, there are several disadvantages during and after operation such as polymerized thermal damaging effect, toxicity and unabsorbable etc. Calcium phosphate cement (CPC) is biocompatible and biodegradable with good biosafty and produce no heat of polymerization, which is a perfect substitute for PMMA.OBJECTIVE: To evaluate the reinforcing effect of CPC on vertebral pedicle screw fixation at biomechanical aspect.DESIGN: Randomized control and repetitive observed measurement.SETTING: Department of Orthopaedics, Second Affiliated Hospital of Nanjing Medical University.MATERIALS: The experiment was conducted in Tongji Medical College of Huazhong University of Science and Technology from August of 2002 to February 2003. ①Two fresh spines from male bodies respectively aged of 52 and 50 years were provided by the Anatomic Department of Tongji Medical College. Ten vertebrae in each spine were obtained (T8-12, L1-5) and taken as 52-year group and 50-year group. Radiographs of these vertebrae were taken to exclude congenital abnormality, fracture, tumor or other pathological changes. Vertebrae in both groups were osteoporoses of grade I and in accordance with experimental requirement.②Main components of solid phase of CPC were micropowder of tricalcium phosphate and tetracalcium phosphate (TTCP) and its main ingredients of liquid phase was citrate solution, which was prepared with solid phase in the ratio of 1g vs 1 mL.Primarily setting-time was 15 minutes and the final setting-time was 12hours with the maximum compressive strength between 45 Mpa and 57 Mpa. ③Diameter of self-made pedicle screws was 5 mm; Length of screw thread segment was 34 mm; Pitch was 2 mm; Depth of screw thread was 0.8 mm.METHODS: ①Biomechanical test of pedicle screw fixation at final solid time of CPC: Vertebrae of 50-year group were taken as testing subjects.Control lateral: vertebral pedicle screws were implanted directly in screw path; Strengthening lateral: vertebral pedicle screws were inserted after fillingwith CPC. After that, specimens were deposited in a thermostated container for twelve hours at 37 ℃. Maximum axial pull-out strength of vertebral pedicle screw was determinated. ②Biomachanical test of vertebra pedicle screw fixation when CPC primarily hardened: specimens in 52-year group were taken as testing subjects. In the same way, vertebral pedicle screw was implanted in the control lateral of vertebral pedicle,while that in the strengthen lateral was implanted after filling of cement,which were placed in the thermostated container for 15 minutes at 37 ℃,the maximum axial pull-out strength of vertebral pedicle in primary setting time were determinated. ③Biomechanical test of CPC in the reinforcement of loose vertebral pedicle screw fixation: vertebrae in 50-year group were selected. Loosened vertebral pedicle screws were re-fixed with CPC for 12 hours. Maximum axial pull-out strength of bilateral screws was tested.MAIN OUTCOME MEASURES: ①Biomechanical testing results of pedicle screw fixation at final solid time of CPC. ②Biomechanical testing results of vertebral pedicle screw fixation when CPC primarily hardened.③Biomechanical testing results of CPC in the reinforcement of loose vertebral pedicle screw fixation.RESULTS: ①Medians of maximum axial pull-out strength of vertebral pedicle screws in control and strengthening laterals in the 50-year group were 620 N and 1 136 N respectively. Compared with control lateral, that in the strengthening lateral increased by 83 % (P < 0.01). Median of anti-cutting stress increased from 1.16 N/mm2 to 2.13 N/mm2 after being strengthened. ②The medians of those in the 52-year group were 554.5 N and 859.5 N respectively and that in the strengthening lateral increased by 55 % in comparison with that in the control lateral (P < 0.01).The median of anti-cutting stress of reinforced bone-screw interface increased from 1.03 N/mm2 to 1.61 N/mm2. ③Maximum axial pull-out strength of vertebral pedicle screws in control and strengthening laterals in the 50-year group of 12 hours after re-fixation were 517 N and 876 N, which respectively increased by 63.6% or 54.2% (P < 0.01) in comparison with median of that of loose screw in the same lateral.CONCLUSION: CPC can enhance vertebral pedicle screw fixation in primary and final setting time, with which loosened screws can be re-fixed.Vertebral pedicle screw in control lateral and strengthening lateral strips from bone-screw interface without peripheral bone and vertebral pedicle being destroyed seriously, which are beneficial to the second insertion of screw.

14.
Artículo en Zh | WPRIM | ID: wpr-538752

RESUMEN

Objective:To elucidate the signal transduction mechanism of the modulation of immune cells by estrogen,the effect of 17?-estradiol(E2)on the production of nitric oxide (NO)from spleen mononuclear cells(MNC)of rats and the expression of inductible NO synthase(iNOS) in estrogen receptor(ER) knockout mice were examined.Methods:Culture of the spleen MNC from normal,Freund's incomplete adjuvant(FIA)or myelin basic protein(MBP) immunized Lewis rats.Detection NO production in the supernatant of culture was determined by Griess reagent.The expression of iNOS in spleen sections were observed by immunofluorescence staining.Results:①E2 dose-dependently induce NO production in spleen MNC from normal rats,MNC from FIA or MBP immunized rats manifest in the same manner.iNOS INHIBITOR l-NAME or MAPK blocker could suppress the induction.②In vivo E2 enhanced iNOS expression in wild type mice(WT),but had no effect in ER ? knockout mice(EPKO).ER? knockout mice(BERKO)appear the same with wt.Conclusion:E2 could modulate the immune system via induction of NO,which involves both genomic and nongenomic mechanisms.

15.
Artículo en Zh | WPRIM | ID: wpr-540651

RESUMEN

Objective To discuss the complications following internal fixation of intra-articular calcaneal fractures and its prevention and treatment. Methods From January 1997 to July 2002, 59 sides of calcaneal fractures in 54 patients were treated with open reduction and Y-shaped plate fixation through lateral approach, most of them supplemented by autogenous bone grafting. According to Sanders classification, 20 sides were accounted for typeⅡ, 24 for type Ⅲ, 15 for type Ⅳ. During operation, lateral roentgenograms were made to assess Bler angle and Gissane angle, Broden view was made to evaluate congruency of the posterior facet. The wounds were drained underneath the lateral flap to prevent hematoma formation. Perioperative antibiotics were used routinely. All the cases were followed-up for an average of 17 months(range, 9 to 48 months). Results The clinical results were evaluated according to Maryland Foot Score, excellent results achieved in 30 cases, good in 21, fair in 6, poor in 2; excellent and good rate was 86.4%. Early complications were found in 4 cases(6.8%). Among them, 2 cases of wound necrosis were treated with suture after resection of necrotic tissue or covered with flap grafts, 1 case of wound infection recovered after dressing changes, 1 case of sural nerve injury recovered uncompletely without any special treatment. Late complications were found in 2 cases(3.4%) with obvious chronic pain, the patients were treated by subtalar arthrodesis and relieved from pain later. Conclusion The complications of internal fixation to fractures are related to anatomic features of calcaneus and their injury mechanism. Serious complications can be minimized in several ways as follows: optimal time for operation and preoperative design should be carefully considered, a full-thickness flap is recommended in avoidance of excessive distraction, bone grafting is needed to support intra-articular fracture fragments and to enhance the stability of internal fixation, the affected extremity should be immobilized by plaster and elevated, and perioperative use of antibiotics.The appropriate management should be taken in cases of complications.

16.
Artículo en Zh | WPRIM | ID: wpr-541268

RESUMEN

Objective:To compare the differences of bond strength usi ng gold intermediate layer between Ni-Cr alloy and opaque porcelain(OP) baked at different temperatures. Methods:36 standard samples of Ni-Cr al loy and 36 of gold were prepared. The samples were divided into 4 groups with 9 in each. In group 1,OP was smeared to the surface of the samples and then baked at 950 ℃. In group 2,3 and 4 blendgold neu(a gold past) was put on the surface of the samples, then baked at 820 ℃,890 ℃ and 960 ℃ respectively. The samples were proccessed for further tests.The bond strength was tested by shear bond te st, and the electron probe was used to observe interfacial bond state and diffus ion of interfacial elements. Results:The bond strength(MPa) in g roup 1,2,3 and 4 was 19.66? 1.83,22.34?2.73,21.33?2.75 and 28.02?5.71 res pectively(group 1 vs group 4 P

17.
Artículo en Zh | WPRIM | ID: wpr-527793

RESUMEN

Objective To explore the effects of fluvastatin on NF-?B activity and osteopontin(OPN) mRNA expression in albumin-induced renal tubular epithelial cells.Methods The renal tubular epithelial cells were cultured with 30 mg/ml fat free bovine serum albumin(BSA) as the control group.The renal tubular epithelial cells in the treatment group were cultured with different concentrations of fluvastatin for different hours.EMSA and RT-PCR were used to observe NF-?B activity and OPNmRNA expression.Results Fluvastatin can inhibit the NF-?B activity and OPNmRNA expression in a time and dose dependent manner.Conclusion Fluvastatin can inhibit NF-?B activity and OPNmRNA expression in albumin induced tubular epithelial cells.

18.
Artículo en Zh | WPRIM | ID: wpr-550671

RESUMEN

Using scanning electromicroscope, seven species of anopheline mosquito eggs were studied. Among them, the microstructure of exochorion of Anopheles liangshanensis. An. kweiyangensis An. kunmingensis, An. hyrcanus and An. messeae were not reported before. The results showed that ultrastructure of plastron network, frill and tubercles of deck were useful in distinguishing sibling species of anopheline eggs. Microstructure of float had little difference between species. The micropylar area and lobed tubercles presented obvious intraspecific variations, so, it should be careful for using in classification.

19.
Artículo en Zh | WPRIM | ID: wpr-677704

RESUMEN

AIM To investigate the effect of tamoxifen on the proliferation of the anterior pituitary cell of rats and its mechanism. METHODS Primary culture of the anterior pituitary cell of rats and 3H TdR incorporation method were applied. The changes of cell morphology were observed directly by electric microscope. RESULTS Tamoxifen could inhibit the proliferation of the anterior pituitary cell of rats. The inhibitory effect of tamoxifen (0 1 ?mol?L -1 ) could be reversed by estrogen.The classical apoptotic changes appeared in the cells after tamoxifen incubation for 48 h. CONCLUSION Tamoxifen can inhibit the proliferation of the anterior pituitary cell of rats and resultin the cell apoptosis.

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