Effects of Prenatal Methcathinone Exposure on the Neurological Behavior of Adult Offspring.

BACKGROUND: Our previous research has shown that prenatal methcathinone exposure affects the neurodevelopment and neurobehavior of adolescent offspring, but the study on whether these findings continue into adulthood is limited. OBJECTIVE: This study aims to explore the effects of prenatal methcathinone exposure on anxiety-like behavior, learning and memory abilities, as well as serum 5-hydroxytryptamine and dopamine concentrations in adult offspring. METHODS: Pregnant rats were injected daily with methcathinone between the 7th and 20th days of gestation. The neurobehavioral performance of both male and female adult offspring rats was evaluated by neurobehavioral tests, including open-field tests, Morris water maze (MWM) tests, and novel object recognition (NOR) tests. The levels of 5-hydroxytryptamine and dopamine concentration in rat serum were detected by ELISA. RESULTS: Significant differences were found in the length of center distance and time of center duration in the open-field test, as well as the times of crossing the platform in the MWM test, between the prenatal methcathinone exposure group and the control group. Results of the NOR test showed that adult offspring rats exposed to methcathinone need more time to discriminate the novel object. No gender differences were detected in the neurobehavioral tests. The serum concentrations of 5-hydroxytryptamine and dopamine in rats exposed to methcathinone prenatally were lower than that in the control group, and the serum dopamine concentration was independent of gender in each group. CONCLUSION: Prenatal methcathinone exposure affects the neurological behavior in adult offspring, and 5-hydroxytryptamine and dopamine might be involved in the process.

Association between lipoprotein(a) and ischemic stroke: Fibrinogen as a mediator.

BACKGROUND: Previous studies have reported lipoprotein(a) was related to increased risk of ischemic stroke. However, the role of fibrinogen in their associations was not fully elucidated. AIM: We aimed to investigate the mediating role of fibrinogen in the association between lipoprotein(a) and risk of ischemic stroke. METHODS: A total of 516 patients with ischemic stroke were matched 1:1 to patients without ischemic stroke for age and gender. Serum lipoprotein(a) and plasma fibrinogen levels were collected on the basis of the results of biochemical tests. Multivariate conditional logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for lipoprotein(a) levels and ischemic stroke risk. Mediation analysis were further conducted to evaluate the potential mediating role of fibrinogen in the association between lipoprotein(a) and ischemic stroke risk. RESULTS: The lipoprotein(a) level of subjects with ischemic stroke was significantly higher than that of subjects without ischemic stroke (P < 0.001). Each SD increment of lipoprotein(a) was associated with 27% higher odds (OR 1.27, 95%CI: 1.11, 1.45) increment in ORs of ischemic stroke. Furthermore, mediation analyses indicated that fibrinogen mediated 10.15% of the associations between lipoprotein(a) and ischemic stroke. CONCLUSIONS: Higher level of lipoprotein(a) was independently associated with increased risk of ischemic stroke and fibrinogen partially mediated the associations of lipoprotein(a) and ischemic stroke risk.

Impaired sensitivity to thyroid hormones is associated with ischemic stroke in young and middle-aged euthyroid population / 西安交通大学学报(医学版)

【Objective】 To investigate the association of thyroid indices with the prevalence of ischemic stroke in young and middle-aged euthyroid population. 【Methods】 For this retrospective study, 620 euthyroid patients aged from 18 to 65 years were divided into ischemic stroke group (n=308) and non-ischemic stroke group (n=312). The characteristics of the study population; serum thyroid indices, i.e., free triiodothyronine (FT3), free thyroxine (FT4) and thyroid-stimulating hormone (TSH), were collected from biochemical test results. Multivariate conditional logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for thyroid indices and ischemic stroke. 【Results】 Compared with non-ischemic stroke group, significant differences were observed in age, gender, weight, smoking status, drinking status, history of hypertension and diabetes, SBP, DBP, FBG, TC, HDL-C, LDL-C, FT3, FT4, FT3/FT4, TFQI, and PTFQI in ischemic stroke patients (all P0.05). Logistic regression analysis revealed that lower FT3 [OR (95% CI) =0.722 (0.547~0.955) , P=0.022] and FT3/FT4 ratio [OR (95% CI) =0.723 (0.600~0.870) , P=0.001] , FT4 [OR (95% CI) =1.099 (1.011~1.194) , P=0.026] were significantly associated with an increased risk of ischemic stroke. After stratified analysis by hypertension, FT4 [OR (95% CI) =1.133 (1.021~1.257) , P=0.019] , lower FT3/FT4 ratio [OR (95% CI) =0.723 (0.600~0.870) , P=0.003] , TFQI [ OR (95% CI) =1.854 (1.026~3.350) , P=0.041] , and PTFQI [OR (95% CI) =1.871 (1.065~3.288) , P=0.029] were significantly associated with an increased risk of ischemic stroke in patients combined with hypertension, while after stratified analysis by diabetes, we only found that lower FT3/FT4 ratio [OR (95% CI) =0.730 (0.559~0.953) , 0.704 (0.536~0.944) , P=0.021] and FT4 [OR (95% CI) =1.170 (1.025~1.335) , P=0.026] were significantly associated with an increased risk of ischemic stroke in patients combined with diabetes. 【Conclusion】 FT3, FT4, and FT3/FT4 ratio are associated with an increased risk for ischemic stroke in young and middle-aged euthyroid population; TFQI and PTFQ are associated with an increased risk for ischemic stroke in patients combined with hypertension.

Remnant cholesterol is associated with triglyceride and glucose index in young and middle-aged patients with ischemic stroke / 西安交通大学学报(医学版)

【Objective】 To investigate the association between remnant cholesterol (RC) and triglyceride and glucose (TyG) index in young and middle-aged patients with ischemic stroke. 【Methods】 A total of 268 patients were divided into two groups, namely low TyG index group (n=134) and high TyG index group (n=134). Characteristics of the study population and metabolism risk factors (TC, TG, HDL-C, LDL-C, UA) were collected from biochemical test results. Spearman correlation analysis was used to analyze the correlation between metabolism risk factors and TyG index. Multivariate conditional logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for RC and TyG index. 【Results】 Compared with the low TyG index group, significant differences were observed for BMI, history of diabetes, history of hypertension, SBP, DBP, FBG, TC, TG, LDL-C, RC, UA, and TyG index in high TyG index group. No significant differences were observed in age, gender, smoking status, or drinking status, HDL-C between the two groups. Spearman correlation analysis indicated that significant linear associations were observed between BMI, SBP, DBP, FBG, TC, TG, HDL-C, LDL-C, RC, UA and TyG index. Logistic regression analysis revealed that the RC, BMI, hypertension, diabetes, TC, LDL-C, and UA were significantly associated with the risk of increased level of TyG index. After adjusted analysis by RC, BMI, hypertension, diabetes, TC, LDL-C, and UA, only RC was significantly associated with an increased risk of increased level of TyG index. 【Conclusion】 Remnant cholesterol was associated with an increased risk of elevated TyG index level in young and middle-aged patients with ischemic stroke.

Protein Kinase C Controls the Excitability of Cortical Pyramidal Neurons by Regulating Kv2.2 Channel Activity / 神经科学通报·英文版

The family of voltage-gated potassium Kv2 channels consists of the Kv2.1 and Kv2.2 subtypes. Kv2.1 is constitutively highly phosphorylated in neurons and its function relies on its phosphorylation state. Whether the function of Kv2.2 is also dependent on its phosphorylation state remains unknown. Here, we investigated whether Kv2.2 channels can be phosphorylated by protein kinase C (PKC) and examined the effects of PKC-induced phosphorylation on their activity and function. Activation of PKC inhibited Kv2.2 currents and altered their steady-state activation in HEK293 cells. Point mutations and specific antibodies against phosphorylated S481 or S488 demonstrated the importance of these residues for the PKC-dependent modulation of Kv2.2. In layer II pyramidal neurons in cortical slices, activation of PKC similarly regulated native Kv2.2 channels and simultaneously reduced the frequency of action potentials. In conclusion, this study provides the first evidence to our knowledge that PKC-induced phosphorylation of the Kv2.2 channel controls the excitability of cortical pyramidal neurons.

CAT, AGTR2, L-SIGN and DC-SIGN are potential receptors for the entry of SARS-CoV-2 into human cells

Since December 2019, the COVID-19 caused by SARS-CoV-2 has been widely spread all over the world. It is reported that SARS-CoV-2 infection affects a series of human tissues, including lung, gastrointestinal tract, kidney, etc. ACE2 has been identified as the primary receptor of the SARS-CoV-2 Spike (S) protein. The relatively low expression level of this known receptor in the lungs, which is the predominantly infected organ in COVID-19, indicates that there may be some other co-receptors or alternative receptors of SARS-CoV-2 to work in coordination with ACE2. Here, we identified twenty-one candidate receptors of SARS-CoV-2, including ACE2-interactor proteins and SARS-CoV receptors. Then we investigated the protein expression levels of these twenty-one candidate receptors in different human tissues and found that five of which CAT, MME, L-SIGN, DC-SIGN, and AGTR2 were specifically expressed in SARS-CoV-2 affected tissues. Next, we performed molecular simulations of the above five candidate receptors with SARS-CoV-2 S protein, and found that the binding affinities of CAT, AGTR2, L-SIGN and DC-SIGN to S protein were even higher than ACE2. Interestingly, we also observed that CAT and AGTR2 bound to S protein in different regions with ACE2 conformationally, suggesting that these two proteins are likely capable of the co-receptors of ACE2. Conclusively, we considered that CAT, AGTR2, L-SIGN and DC-SIGN were the potential receptors of SARS-CoV-2. Moreover, AGTR2 and DC-SIGN tend to be highly expressed in the lungs of smokers, which is consistent with clinical phenomena of COVID-19, and further confirmed our conclusion. Besides, we also predicted the binding hot spots for these putative protein-protein interactions, which would help develop drugs against SARS-CoV-2.

Effects of Methcathinone Exposure during Prenatal and Lactational Periods on the Development and the Learning and Memory Abilities of Rat Offspring.

This study aimed to investigate the effects of prenatal and lactational methcathinone exposure on the development and the learning and memory abilities of rat offspring using a Sprague-Dawley rat model. Pregnant and lactating rats were administered a consecutive daily dose of methcathinone (0.37 mg/kg) or an equivalent volume of saline by injection on gestational days 7-20 and postnatal days 2-15, respectively. The physical development and neurobehavioral test results of rat pups were recorded throughout the lactation period. Morris water maze (MWM) and novel object recognition (NOR) tests were performed from postnatal day 35 to day 42 to assess the learning and memory abilities of rat offspring in adolescence. The occurrence of hair growth and developments in neurological reflexes, such as improvements in limb grasp, righting reflex, and gait, were delayed in pups after perinatal methcathinone exposure compared with that in the control. Results from MWM and NOR tests indicate that perinatal methcathinone exposure induced deficits in spatial memory, learning ability, and novel object exploration in the adolescent offspring compared with that in the control. The impairment of spatial learning and memory was greater in the prenatal exposure group, while the impairment of novel object exploration was greater in the lactational exposure group. These data show that the prenatal and lactational methcathinone exposure induced the delay of physical and neurological reflex development and impaired learning and memory in rat offspring.

Recognition of three different imagined movement of the right foot based on functional near-infrared spectroscopy / 生物医学工程学杂志

Brain-computer interface (BCI) based on functional near-infrared spectroscopy (fNIRS) is a new-type human-computer interaction technique. To explore the separability of fNIRS signals in different motor imageries on the single limb, the study measured the fNIRS signals of 15 subjects (amateur football fans) during three different motor imageries of the right foot (passing, stopping and shooting). And the correlation coefficient of the HbO signal during different motor imageries was extracted as features for the input of a three-classification model based on support vector machines. The results found that the classification accuracy of the three motor imageries of the right foot was 78.89%±6.161%. The classification accuracy of the two-classification of motor imageries of the right foot, that is, passing and stopping, passing and shooting, and stopping and shooting was 85.17%±4.768%, 82.33%±6.011%, and 89.33%±6.713%, respectively. The results demonstrate that the fNIRS of different motor imageries of the single limb is separable, which is expected to add new control commands to fNIRS-BCI and also provide a new option for rehabilitation training and control peripherals for unilateral stroke patients. Besides, the study also confirms that the correlation coefficient can be used as an effective feature to classify different motor imageries.

Clinical efficacy of fractional CO 2 laser treatment for vaginal relaxation syndrome / 中华医学美学美容杂志

Objective:To evaluate the clinical efficacy and safety of fractional CO 2 laser for the treatment of vaginal relaxation syndrome. Methods:Twenty-one females with vaginal relaxation syndrome receiced between December 2016 and January 2017 in our department were treated for 3 times at 1 month interval with femilift fractional CO 2 laser. Vaginal palpation, vaginal squeeze pressure test, vaginal ultrasound, pelvic floor MRI, and Incontinence Questionnaire Short-Form (ICIQ-SF) assessments were performed at baseline and at post-treatment. Results:Significant improvement in female sexual dysfunction and stress urinary incontinence was especially seen based on patient＇s feelings after treatments. A noted progressive differences were observed in FSFI and vaginal pressure test, which were much higher after treatment than before treatment ( P<0.01). Moreover, in 13 cases suffering from mild to moderate stress urinary incontinence (SUI), fractional CO 2 laser treatment was associated with a significant improvement of ICIQ-SF scores ( P<0.01). All subjects successfully completed the study with no adverse events such as infections, bleeding and pain, etc. Conclusions:Fractional CO 2 laser treatment is an effective treatment for female sexual dysfunction and stress urinary incontinence caused by vaginal relaxation syndrome.

Effects of subchronic aluminum exposure on long-term potentiation and activities of RAS and extracellular regulated protein kinases in rats / 中华劳动卫生职业病杂志

Objective@#To study the effects of subchronic aluminum exposure on LTP and activities of RAS and ERK in rats in vivo.@*Methods@#24 Wistar rats were randomly divided into control group、low-dose group、medium-dose group and high-dose group, and received saline (control group) or Al (mal) 3 (15 μmol、kg、30 μmol、kg or 45 μmol/kg) via intraperitoneal injection (i.p.) for 8 weeks, respectively. The fEPSP in CA1 region were recorded by field potentiation technique in vivo and the hippocampal activities of RAS and ERK were examined by ELISA.@*Results@#The fEPSP amplitudes of the control group were 1.90±0.19, 1.64±0.15 and 1.54±0.08 at 1, 30 and 60 min after HFS, respectively. The fEPSP amplitudes of the low-dose group were 1.40±0.06 at 60 min, which represented a statistically significant decrease compared to the control group (P<0.05) ; these values at 30min and 60min dropped to 1.33±0.20 and 1.12±0.07 in the medium-dose group (P<0.05) and further decreased to 1.05±0.05 and 0.91±0.10 in the high-dose group (P<0.05) . And the activity dose-dependent decreases were observed both in RAS and ERK: compared with the control group and the low-dose group, the activities of RAS and ERK of the medium-dose and high-dose group significantly decreased (P<0.05) and compared with the medium-dose group, the activities of the high-dose group statistically dropped (P<0.05) .@*Conclusion@#RAS and ERK may be related to the suppression of LTP by subchronic aluminum exposure and the RAS-MAPK transduction pathway may be involved in the damage of learning and memory induced by aluminum.

The problems and solving countermeasures in application of nursing vertical management in five hospital in Beijing / 中华护理杂志

Objective To explore the problems and solving countermeasures in application of nursing vertical management,and provide references for nursing post management reform.Methods Through purposive sampling method,nursing administers,clinical nurses,heads of clinical departments and performance directors from five hospitals were interviewed by semi-structured interview method.Data were analyzed using 7-step Colaizzi's phenomenological analysis method.Results Four themes were formed about the problems in application of nursing vertical management,including:affecting department management and doctor-nurse collaboration,insufficient scientificity and fairness of performance evaluation,significant issues regarding post setting of senior nurses,competence and sense of belonging of temporarily deployed nurses.Four themes were formed about the solving countermeasures in application of nursing vertical management,including:improving participation of clinical departments in nursing management,making performance system to public and asking advices of nurses,providing career development for senior nurses,and conducting standardized training and establishing reserve nurses tank.Conclusion The main problems in application of nursing vertical management consisted of affecting department management and doctor-nurse collaboration,insufficient scientificity and fairness of performance evaluation,post setting of senior nurses,and competence and sense of belonging of temporarily deployed nurses.We suggested to better apply nursing vertical management by improving participation of clinical department in nursing management,making performance system to public and asking advices of nurses,providing career development for senior nurses,and conducting standardized training and establishing reserve nurses tank.

The pilot study on the expression of PHF8, H3K9me2, BDNF and LTP in the hippocampus of rats exposed to aluminum / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>In this research, we have observed changes of PHF8、H3K9me2、BDNF, and their regulatory roles in changing the amplitude value of LTP in hippocampus due to aluminum exposure so that we can discuss the impact on the learning and memory that caused by chronic aluminum exposure.</p><p><b>METHODS</b>Forty healthy SPF grade SD male rats were randomly divided into four groups by weight, including control group and low, medium, high dose aluminum exposed group, each group had 10 rats. The exposed rats drank water containing different doses of aluminum chloride (AlCl3) (2、12、72 mg/kg Al(3+)) for 90 d. We measured LTP in hippocampus by electrophysiological grapier and detected the expression of PHF8、H3K9me2、BDNF by western-blot.</p><p><b>RESULTS</b>Electrophysiological measurements shows that compared with that of control group, the average of fEPSPs was decreased at different time points in all exposed groups (P<0.01) . The results of western-bolt test demonstrated that the expression of PHF8 in the exposed groups were significantly lower than those of control group (P<0.01) . And the expression the of H3K9me2 of medium and high dose groups were significantly higher than control group (P<0.05) . While the expression of BDNF of medium and high dose groups were decreased compared with the control group (P<0.05) .</p><p><b>CONCLUSION</b>Chronic aluminum exposure can reduce the LTP via the route of PHF8-H3K9me2-BDNF in the hippocampus of rats, which then may impair the ability of learning and memory.</p>

The study on the relationship between hippocampus neuronal apoptosis and hippocampus synaptic plasticity in rats exposed to aluminum / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effect of aluminum exposure on neuronal apoptosis of rats hippocampus and the correlation of and synaptic plasticity.</p><p><b>METHODS</b>There were 40 SPF grade SD rats which were randomly divided into four groups: the control group, the low dose group, the medium dose group and the high dose group, 10 rats in each group. The rats were daily gavaged with aluminum lactate for 30 days. The hippocampal fEPSPs in rat was measured by electrophysiological grapher and the neuronal apoptosis in hippocampus was detected by Flow cytometer. In addition, the relative expression of gene which includes caspase-3, 8, 9 was measured by Real-time PCR.</p><p><b>RESULTS</b>Compared to the control group, the average of fEPSPs which after HFS 10, 20, 30, 40, 50, 60 min was decreased at different time point in the low dose group, the medium dose group and the high dose group (P < 0.05). Compared with the control group, the rate of apoptosis was significantly increased in the medium dose group and the high dose group (P < 0.05). Compared to the control group, the relative expression of caspase-3 in the medium dose group and the high dose group was significantly increased in Real-time PCR (P < 0.05), and the relative expression of caspase-8 in the high dose group was significantly increased (P < 0.05).</p><p><b>CONCLUSION</b>Aluminum exposure may induced neuronal apoptosis in rats, and then affect hippocampal synaptic plasticity.</p>

Antibacterial mechanism of silver nanoparticles：a dose-dependent promotion of cell apoptosis / 中国组织工程研究

BACKGROUND:Silver nanoparticles (AgNPs) show strong antibacterial effect and are not easy to have drug resistance. But the antibacterial mechanisms of AgNPs have not been wel developed. OBJECTIVE:To explain the antibacterial mechanisms of AgNPs. METHODS:We investigated the influence of Ti, TiO2 and TiO2 containing AgNPs onEscherichia coliand Staphylococcus aureus by bacterial inhibition ring test. Escherichia coli was cultured in LB liquid medium with 0, 5, 10 mg/L AgNPs. We measured the absorbance value of bacterial culture. DNA gel electrophoresis was used to study the effect of AgNPs onEscherichia coliDNA. Then we researched the character of apoptosis on Escherichia coli by Annexin V and PI staining, using flow cytometry. RESULTS AND CONCLUSION:The inhibiting effect of Ti and TiO2 onEscherichia coliandStaphylococcus aureus was not obvious. But the inhibition rings of TiO2 containing AgNPs to bacteria appeared. The absorbance value of Escherichia coliculture was reduced whenEscherichia coliwas co-cultured with AgNPs. And this decrease tendency was in direct proportion with AgNPs concentration. AgNPs reduced the amount of DNA of Escherichia coli and this tendency was directly proportional with AgNPs concentration. TheEscherichia coli apoptosis rate induced by AgNPs was increased and this tendency was positively correlated to the AgNPs concentration. These results indicate that AgNPs can induce bacterial apoptosis to influence the growth of bacteria.

Construction of a 5-Lipoxygenase Transgenic Mice / 中国实验动物学报

Objective To construct a 5-lipoxygenase (5-LO) transgenic mouse model of atherosclerosis.Methods Purified 5-LO fragment was injected into male pronucli and the firtilized eggs were transplanted into pseudopregnant mice.PCR and Southern blot were used to detect the genotype of DNA separated from the newborn mouse tail tissues.RT-PCR and Western blot analysis were used to detect the gene transcription and expression.Results PCR and Southern blot results showed that 7 of 25 mice were transgenic mice.Expression of 5-LO and FLAP was found in the bone marrow,spleen,kidney,and peritoneal cells.Results of RT-PCR and Western blot showed that No.9,20,24transgenic mice expressed a higher level of 5-LO and FLAP than those in the wild type C57BL/6 mice.The expression levels in bone marrow and peritoneal cells were significantly different(P<0.05).Conclusion A 5-LO transgenie mouse line has been established in this study and may be used for future study on the function of 5-LO gene.

Chiral Separation and Enantiomerization of Triazole Pesticides / 分析化学

The chiral separation of three triazole pesticides, i.e. diniconazole, triadimefon and triadimenol was studied on a Chiralcel OJ-H and a Chiralcel OD-H HPLC chiral columns. The optical rotation quality of diniconazole and triadimefon enantiomers was measured and the absolute configurations of individual enan-)tiomers) were further concluded. On this basis, the absolute configurations of the four triadimenol stereoisomers were deduced via the reductive experiment of triadimefon to triadimenol. Furthermore, the chiral stability of the three triazole pesticides in organic solvents and buffer solutions was investigated. The results showed the obvious enantiomerization was observed as for triadimefon in methanol, ethanol and water, whereas dinicona-)zole) and triadimefon were chiral stable in organic solvents and water. The enantiomerization of triadimefon would be accelerated at higher temperature and in alkaline media.

Risk factor study and analysis of recurrent cerebral infarction / 中国基层医药

Objective To explore the risk factors of recurrent cerebral infarction and the preventive meas-ures. Methods The risk factors were compared between recurrent group (246 cases with recurrent cerebral infarc-tion) and unrecurrent group( 100 cases with unreeurront cerebral infarction) by means of multiple logistic regression analysis. Results The recurrent cerebral infarction is correlated closely with hypertension, diabetes, heart diseases and excessive drinking, and the OR values arc 2.206, 2.232, 2.252, 2.842, 2.366 respectively (P<0.05), prophy-lactic treatment had the protective effects against the recurrent cerebral infarction,and the OR value was 0.249. Con-dusions The main risk factors of recurrent cerebral infarction were hypertension,heart diseases,excessive drinking. Prophylactic treatment hed great significance in preventing the recurrence of cerebral infarction.

Ventilator-associated Pneumonia Following Severe Craniocerebral Trauma and Its Clinical Characteristics / 中华医院感染学杂志

OBJECTIVE To explore the characteristics of the pathogens in ventilator-associated pneumonia (VAP) following severe craniocerebral trauma. METHODS The 220 cases with severe craniocerebral trauma were analyzed retrospectively. RESULTS The incident rate of VAP was 24% in these patients. A total of 169 pathogens were isolated,including 146 ( 86%) strains of bacteria and 23 (14%) fungal isolates. The main Gram-negative bacteria (114 strains) were Pseudomonas aeruginosa,Escherichia coli,Klebsiella pneumoniae,etc. The Gram-positives (32 strains) were Staphylococcus aureus and twenty-four (75%) of them were meticillin-resistant. CONCLUSIONS The incident rate of VAP is high following severe craniocerebral trauma. Most of the isolated pathogens are drug resistant. These cases have mixed infection occurred commonly. To prevent and treat VAP,we should pay attention to disinfection and aseptic manipulation,and make the rational use of antimicrobial agents.

The effects of combined general-epidural anaesthesia on perioperative myocardial enzymogram and troponin T of the myocardium in old patients undergoing thoracic surgery / 中国医师进修杂志

Objective To observe the effects of combined generalepidural anesthesia on perioperative myocardial enzymogram and troponin T of the myocardium(cTnT)in old patients undergoing thoracic surgery.Methods Thirty-eight ASAⅠ-Ⅱ patients aged 60～80 years old were randomly divided into two groups.General anesthesia group(group G): anesthesia was induced with fentanly,propofol and vecuronium and maintained with isoflurane,propofol and vecuronium.Combined anesthesia group(group C):general anesthesia was performed as in group G and continuous epidural block with(1.6%) lidocaine was added during operation.Peripheral blood CK,CK-MB,AST,LDH and cTnT were measured before anesthesia,at the end of operation and at 6,24,48 hours after operation.Results Two groups could provide same postoperative analgesia.There was no change for HR,RR and MAP in two groups.Serum CK,AST,LDH and cTnT concentration in group G after operation were significantly higher than those before anesthesia(P

Progress in researches on the synthesis of poly (propylene fumarate) and its crosslinking characteristics / 生物医学工程学杂志

Poly (propylene fumarate) is an unsaturated linear polyester, which degrades, in the presence of water, into propylene glycol and fumaric acid, and the degradation products can be cleared from the human body by normal metabolic processes. In this paper, different methods of the synthesis of PPF are listed, the crosslinking characteristics of polymerizing composite as well as the mechanical properties of cross-linked composite are discussed, and the potentialities of PPF composite used as particularly degradable polymeric cement for orthopedic application are reviewed.