Current situation of animal injury among school children in Chongqing / 公共卫生与预防医学

Objective To investigate the current situation of animal injury among children in Chongqing, and to provide a scientific basis for relevant departments to formulate and implement strategies and measures to prevent and control animal injury to children. Methods According to the method of multi-stage stratified cluster sampling, 14,056 children in grades 4-12 in four districts of Chongqing were selected as the investigation subjects, and the occurrence of animal injuries in the past 6 months was investigated. Results The incidence of animal injury among school children in Chongqing was 0.35% and the incidence of person-time was 0.36%. The incidence rate in males (0.48%) was higher than that in females (0.31%). The incidence rate in urban children (0.43%) was higher than that in rural children (0.30%). The incidence of animal injury was the lowest in nuclear families (0.25%), and the highest in single-parent families (0.82%). There were statistically significant differences in the incidence of animal injuries in children among different fathers' occupational types, family types and parents' parenting styles (P<0.05).  The main place of child animal injury was home (57.14%). Recreational activities were the main cause of animal injury (51.02%). The main injuries were lower limbs (42.86%), upper limbs (24.49%) and head (10.20%). Conclusion The prevention and control of children's animal injury in Chongqing should focus on boys and families. It is suggested to take targeted and comprehensive interventions to prevent animal injuries in children.

Study on prevalence of physical activity in rural residents in four counties (districts) of Shanxi and Chongqing / 中华流行病学杂志

Objective: To investigate the prevalence of physical activity and its influencing factors in rural residents in Shanxi and Chongqing. Methods: In four counties (districts) of Shanxi and Chongqing, local residents aged ≥18 who lived there for more than one year and had no plan to migrate to other areas in 2 years were surveyed through face to face questionnaire interviews to collect the information about their daily physical activity time, sedentary time, related knowledge and attitude, and others. Results: The physical inactivity rate of the residents was 14.9%, and 88.7% of residents never took daily physical activity. The average sedentary time was (3.91±2.06) hours. The results of multivariate analysis showed that education level, per capita monthly income and activity degree were the factors influencing physical inactivity. Conclusion: The proportion of people who never took daily physical activity in the survey area was higher than the average level in rural areas in China, so measures should be taken to improve the overall rate of physical activity. For people who have exercise willingness, but have no practice, and those who have already increased their physical activities, targeted guidance is needed on the basis of strengthened health education.

Study on prevalence of physical activity in rural residents in four counties (districts) of Shanxi and Chongqing / 中华流行病学杂志

Objective To investigate the prevalence of physical activity and its influencing factors in rural residents in Shanxi and Chongqing.Methods In four counties (districts) of Shanxi and Chongqing,local residents aged ≥ 18 who lived there for more than one year and had no plan to migrate to other areas in 2 years were surveyed through face to face questionnaire interviews to collect the information about their daily physical activity time,sedentary time,related knowledge and attitude,and others.Results The physical inactivity rate of the residents was 14.9％,and 88.7％ of residents never took daily physical activity.The average sedentary time was (3.91 ± 2.06) hours.The results of multivariate analysis showed that education level,per capita monthly income and activity degree were the factors influencing physical inactivity.Conclusion The proportion of people who never took daily physical activity in the survey area was higher than the average level in rural areas in China,so measures should be taken to improve the overall rate of physical activity.For people who have exercise willingness,but have no practice,and those who have already increased their physical activities,targeted guidance is needed on the basis of strengthened health education.

Model establishment and injury assessment of chlorpyrifos dynamic-inhalation of rats / 中国药理学与毒理学杂志

OBJECTIVE To establish a model for chlorpyrifos(CPF)whole-body dynamic inhalation exposure in SD rats and investigate the injury effects after acute exposure by CPF. METHODS By optimizing the aerosol parameters ,the animal acute dynamic inhalation exposure of CPF was established. Absorption sampling-gas phase detecting technology was used to monitor the concentration of CPF in the whole-body dynamic-inhalation exposure cabin by exploring the relationship between the concentration , particle size of CPF aerosol and the CPF inhalation time in the exposure cabin via a particle size detector. Using Bliss method,specific pathogen free SD male rats were allocated to the environment of CPF exposure at different lethal concentrations and time points. The symptoms and deaths of these SD male rats in different groups were recorded within the following 10 d. Based on the median lethal concentra?tion time(LCt50),the values of plasma cholinesterase(ChE)were checked at different time points after being exposed at different doses. RESULTS The mean concentrations of CPF aerosol at nine time points was 160.6 mg · m-3,the relative standard deviation value was 6.9%;the geometrical mean of aerosol particle size was 1.1 μm,and the geometric standard deviation was 1.8. The results met the technical requirements of Organization for Economic Cooperation and Development regarding acute inhalation exposure. Under these equipment conditions,the LCt50 of CPF acute inhalation of SD male rats was 1654.2 mg · m-3 · h,suggesting that plasma ChE inhibitory rate was higher with the increase in the exposing dose,and that there was a significant difference as compared with the controls(P<0.05). CONCLU?SION The model for whole-body dynamic-inhalation exposure of CPF is applicable to rats,which can serve as an experimental platform and technical support to inhalation vulnerability and the research on prevention and cure of organophosphate industrial products and nerve agents.

Progress in treatment and study of renal toxicity by mercury poisoning / 中国药理学与毒理学杂志

Mercury is one of the common heavy-metal toxins,which can cause damage throughout the body in a variety of ways. Cases of renal toxicity of mercury poisoning are increasing clinically. However,little is known about nephrotoxicity mechanisms,and treatment remains unsatisfactory. The mechanism of mercury toxic nephropathy is reviewed in this paper,including the direct toxic effect on the kidney,the injury to the biomembrane system,generation of Hg-metallothionein,imbalance of intra?cellular calciumion,oxidative damage,induced apoptosis,and immune injury. Besides,the mechanism and limitation of common therapies,potential developments of the field are discussed. This review will facilitate further investigations therapies about both the mechanism and treatment of mercury toxic nephropathy.

Anticonvulsant effect of intranasal midazolam on maximal electroshock seizure and metrazol seizure model in rats / 军事医学

Objective To evaluate the anticonvulsant effect of midazolam and diazepam when administered nasally on maximal electroshock seizure and metrazol seizure threshold test models .Methods Rats were randomly divided into 7 groups:model group, low-dose, middle-dose and high-dose of midazolam nasal spray groups , diazepam nasal spray in low-dose, middle-dose and high-dose of midazolam nasal spray groups .After the establishment of the maximal electroshock seizure( MES) and metrazol seizure threshold test models ( MST) in rats, the anticonvulsant effects of different doses of midazolam and the clinically used antiepileptic drug diazepam were evaluated and compared .HE staining was used to observe the histopathological changes in the hippocampus , cortex and amygdala in rats .Results Significant anticonvulsant effects were observed on MES and MST in rats pretreated with different dosages of midazolam .In addition , the anticonvul-sant effects of midazolam were stronger than those of diazepam at the same dosage on MES and MST (P<0.05,P<0.01). Histopathological results showed that both midazolam and diazepam could effectively prevent the seizure -induced brain inju-ries, inhibit the increase of microglial cells and the inflammatory cell infiltration in the hippocampus, cortex and amygdala, and reduce the nucleus pycnosis and neuronophagia .Conclusion Midazolam has significantly anticonvulsant and neuropro-tective effects on different seizure models when administered nasally in rats .

Efficiency of hemoperfusion on clearing thallium based on atomic absorption spectrometry / 中华危重病急救医学

ObjectiveTo determine thallium in whole blood by atomic absorption detection method, and to investigate the eliminating effect of hemoperfusion (HP) for thallium in blood.Methods The blood of Beagle dogs which had not exposed to thallium before were obtained for preparation of thallium nitrate (TlNO3)-containing solution in three concentrations according to the conversion formula based on animal weight and volume of blood. HP was performed in the simulated in vivo environment. The content of TlNO3 in blood of the next group was determined on the amount of TlNO3 for the last HP of the former dose group. Thallium quantity in different samples was measured with atomic absorption spectrometer blood samples before and after HP. Finally, the thallium concentration in blood was analyzed statistically.Results Thallium concentrations showed a good linear relationship in the range of 0-200μg/L (r = 0.998 4). The intra-day precision (RSD) was lower than 4.913%, the intra-day recovery rate was 96.2%-111.9%; the inter-day precision (RSD) was lower than 7.502%, the inter-day recovery rate was 89.6%-105.2%. The concentration of thallium in blood was significantly reduced after HP per time in high, middle, and low dose groups [(453.43±27.80) mg/L to (56.09±14.44) mg/L in high dose group,F = 8.820,P = 0.003;(64.51±13.60) mg/L to (3.19±0.23) mg/L in middle dose group,F = 36.312,P = 0.000; (5.40±0.98) mg/L to (0.38±0.25) mg/L in low dose group,F = 46.240,P = 0.000]. The adsorption rate of four times of HP in high, middle and low dose group were (87.63±2.48)%, (95.06±1.54)% and (92.76±4.87)%, respectively, without significant difference (F = 4.231,P = 0.070 ).Conclusions The method for measuring thallium was established, and it shows a very stable, simple, sensitive for determination of thallium. HP can effectively remove thallium from blood. Thallium concentration can be reduced by 90% after four times of HP. HP is also effective even when thallium concentration is not high.

CHINET 2012 surveillance of antibiotic resistance in Acinetobacter baumannii isolates in China / 中国感染与化疗杂志

Objective To investigate the antimicrobial resistance in the A cinetobacter baumannii strains in different parts of China during 2012 .Methods A total of 8 739 clinical isolates of Acinetobacter were collected from 13 general hospitals and two children’s hospitals ,of which most were A . baumannii (89 .6% , 7 827/8 739 ) . Antimicrobial susceptibility testing was carried out by means of Kirby-Bauer method according to the unified protocol . The susceptibility testing data were analyzed by WHONET 5 .6 software according to CLSI 2013 breakpoints .Results Majority (85 .4% ) of the Acinetobacter strains were isolated from inpatients .The remaining 14 .6% were from outpatients and emergency room patients .Of the 7 827 strains of A .baumannii , 10 .9% ,35 .2% ,35 .7% and 43 .4% were resistant to tigecycline ,minocycline ,cefoperazone-sulbactam and amikacin , respectively .The percentage of A .baumannii resistant to imipenem and meropenem was 63 .5% and 68 .2% ,respectively . The antimicrobial resistant pattern varied in different hospitals . The resistance of A . baumannii varied between different clinical departments .A number of pandrug resistant (PDR) (20 .0% ,1 567/7 827) and multidrug-resistant (MDR) (45 .0% , 3 521/7 827 ) A . baumannii were identified . Conclusions A . baumannii is the most popular pathogenic bacteria among Acinetobacter .The antibiotic resistance of A .baumannii is still increasing .Cefoperazone-sulbactam and minocycline has good in vitro antibacterial activity against A .baumannii .The antibiotic resistance of A .baumannii varies greatly with hospital and department .

Antagonism of obidoxime on sarin induced miosis and visual impairment in rabbits / 中国药理学与毒理学杂志

OBJECTIVE The antagonism of obidoxi me on sarin induced miosis and visual impair-ment was evaluated and its antagonistic mechanism was investigated.METHODS ① 30 min after sarin (2 μg /0.1 mL per eye)was given as an eyedrop,the ability of the 2.5%,5.0%,7.5% obidoxi me and 1 .0% atropine to reverse effects of sarin on pupil dia meter and light reflex were evaluated at different ti mes.② Another 36 rabbits received sarin and at 30 min afer sarin exposure,the drugs above were ad-ministrated and their effects on pupillary light reflex,as well as the AChE activity of cornea,iris and reti-na were recorded 4h after the treatment.RESULTS ① Miosis and impaired pupillary light reflex oc-curred soon after sarin exposure but the abnormal pupil width and pupillary light reflex had disappeared by 48 h after sarin exposure;Subcequent to 1 .0% atropine treatment,the pupil dilatedinstead while the impaired light reflex did not i mprove significantly;unlike atropine,soon after ad ministration of 2.5%, 5.0%,7.5% obidoxi me,the pupil dia meter and light reflex were significantly increased(P <0.01 )and then had beco me normal totally by 24 h post-dose,much faster than those of the control and atropine treatment group.However,there was no significant difference in the recovery ti me between the different dose groups of obidoxi me.② 4h after treatment,the AChE activity in cornea and irisof sarin-treated group were (42 ±4)%,(26 ±2)%,respectively;the AChE activity in cornea of 2.5%,5.0%,7.5%obidoxi me were (74 ±1 1 )%,(81 ±10)% and (74 ±7)%,respectively,and the AChE activity in iris were(39 ±10)%,(43 ±8)% and (43 ±8)%,respectively ,co mpared with sarin-treated group,AChE activities of cornea and iris as well as light reflex of the obidoxi me-treated group were significantly increased(P<0.01 ).But there was no difference in light reflex and AChE activity between the sarin-treated and atropine-treated groups.CONCLUSION Obidoxi me showed better antagonism of sarin-induced ocular effects than that of the commonly used drug,atropine;the antagonistic mechanism is likely closely related to its rapid reactivation of the inhibited AChE in the cornea and iris.

Reactivation of nanoparticulated HI-6 on acetylcholinesterase activity in soman poisoned mice / 中国药理学与毒理学杂志

OBJECTIVE Based on different drug loading models,three types of nanoparticulated HI-6 were prepared and their reactivations on inhibited acetylcholinesterase (AChE)in peripheral and central nervous syste ms were evaluated and compared in so man-intoxicated mice.METHODS Three kinds of nano-reactivators including HI-6 loaded human serum albunin nanoparticle (HSA-HI-6 NP),HI-6 absorptive mesoporous silica nanoparticle(MSN-HI-6),polylactico-glycolic acid nanoparticle coated HI-6 (PLGA-HI-6 NP)were prepared.The characteristic of all blank nanocarriers was observed through elec-tron microscope.HI-6 release rate of nano-reactivators was also determined in vitro.Then the reactiva-tion rate of nano-reactivators at a constant HI-6 dosage(22 mg·kg -1 )on so man-inhabited AChE both in blood and brain was assessed the so man intoxicated mice(120 μg·kg -1 ,sc).RESULTS All the syn-thetic nanocarriers met the de mand for nanodrug use in vivo.The rate of HI-6 release of nano-reactiva-tors was HI-6 >HSA-HI-6 NPs >MSN-HI-6 >PLGA-HI-6 NP in vitro.On the reactivations of so man-inhibited mice blood AChE,the free HI-6 and HSA-HI-6 NPs,as well as MSN-HI-6 showed co mparable reactivation rates(20% -30%)but were greater than that of PLGA-HI-6 NPs (6.2%)(P <0.01 ). However on the reactivations of so man-inhibited mice brain AChE,the reactivation rate of HSA-HI-6 NP (15.3%)was significantly higher than that of PLGA-HI-6 NP(3.3%)and free HI-6(6.3)(P<0.01 ).In addition,MSN-HI-6 group had a significant reactivation rate compared to PLGA-HI-6 NPs(P <0.01 ). But there was no statistic difference between MSN-HI-6 and free HI-6.CONCLUSION The reactivation potency changed obviously with different drug loading models and HSA-HI-6 NPs had the most potent reactivation on so man-inhibited AChE in both blood and brain.

A method for rapid detection of Mycoplasma pneumoniae and its macrolide resistance mutation / 中华检验医学杂志

Objective To develop a method for rapid detection of Mycoplasma pneumoniae and its macrolide resistance mutation. Methods The primers and cycling probe sets were designed to detect two single nucleotide mutation, A2063G and A2064G, in the 23s rRNA gene of Mycoplasma pneumoniae. By using recombinant plasmids containing 23s rRNA gene fragments, 102 Mycoplasma pneumoniae clinical isolates from 2005 to 2008, and 136 nasopharyngeal suction specimens from pediatric patients with low respiratory tract infections in Shanghai Children's Hospital from November to December in 2009 were investigated to determine the specificity and the sensitivity of the CycleavePCR method. PCR amplification and sequence analysis of 23S rRNA genes were performed for all Mycoplasma pneumoniae strains and Mycoplasma pneumoniae positive specimens to confirm the results of the CycleavePCR method. Results Of 102 clinical isolates, 83 was resistant to erythromycin and sequence results show that all macrolide-resistant Mycoplasma pneumoniae strains harbored an A2063G ( 82/83 ) or A2064G ( 1/83 ) transition mutation in 23S rRNA genes. Twelve was Mycoplasma pneumoniae detected positive by CycleavePCR in 136nasopharyngeal suction specimens. The CycleavePCR results were consistent with those of routine PCR and sequencing. There was no signal production from other bacterial species. Sensitivity and specificity were 100%. The detection limit of the CycleavePCR was 10 plasmid copies per reaction. Experiment can be done within 1.5 h. Conclusion A novel method is developed to detect erythromycin-resistant strains harboring A2063G and A2064G transition mutation in the 23s rRNA gene using CycleavePCR.

In vitro antimicrobial susceptibility of Mycoplasma pneumoniae and mechanism of macrolide resistance for isolates obtained in Shanghai from 2005 to 2008 / 中华微生物学和免疫学杂志

Objective To learn the current in vitro antimicrobial susceptibility of Mycoplasma pneu-moniae in Shanghai and to understand the mechanisms of resistance to macrolides. Methods M. pneumoniae was isolated from pediatric patients with low respiratory tract infections(RTI) using broth and PPLO agar medi-um. PCR amplification and sequence analysis of P1 adhesion gene were performed to identify all M. pneumoniae strains. Susceptibility testing was carried out for macrolides, tetracyclines and fluoroquinolones using broth mi-crodilution method with SP4 broth. PCR amplification and sequence analysis of 23S rRNA genes were performed for all M. pneumoniae strains. P1 gene PCR-RFLP typing was performed to subtype the M. pneumoniae strains. Results One hundred and two M. pneumoniae strains were isolated in Shanghai from Oct 2005 to Dec 2008. All M. pneumoniae isolates were susceptible to the tetracyclines and fluoroquinolones tested. Of 102 clinical isolates, 83(81.4%) was resistant to erytbromycin and all 83 erythromycin-resistant strains had MIC>128 mg/L. An increasing trend of resistance rates were showed: 16.7% (1/6) in 2005, 76.5% (13/17) in 2006, 100.0% (24/24) in 2007 and 81.8% (45/55) in 2008. All macrolide-resistant M. pneumoniae strains harbored an A2063G transition mutation in domain V of 23S rRNA genes. The P1 gene RFLP type 1 is predominant (85.3%, 87/102) in M. pneumoniae clinical isolates. Conclusion The macrolide resistance rate of M. pneu-moniae is very high in Shanghai. The mechanism of macrolide resistance is associated with transition mutation on the 23S rRNA gene.

Leukocidin prevalence and molecular epidemiology of methicillin-resistant Staphy-lococcus aureus / 中国感染与化疗杂志

Objective Methicillin-resistant Staphylococcus aureus (MRSA) is a growing public health concern that has been associated with pediatric fatalities. This study investigated the genotypes of staphylococcal cassette chromosomal mec (SCCmec) and Panton-Valentine Leukocidin (PVL) in MRSA strains isolated from Shanghai Children's Hospital by PCR. Methods A total of 30 strains of MRSA were isolated from various clinical specimens from October 2005 to June 2006. The antimicrobial susceptibility was measured by agar diffusion method. SCCmec typing was conducted using a novel multiplex PCR assay allowing for concomitant detection of methicillin resistance (mecA gene) to facilitate detection and classification of all currently described SCCmec typesⅠ, Ⅱ, Ⅲ, Ⅳa, b, c, d andⅤ. PVL gene was also determined by PCR. Results mecA gene was positive in all the strains. SCCmecⅡ was identified in 6(20.0%) isolates, SCCmecⅢ in 15(50.0%) isolates, SCCmecⅤ in 2 and SCCmecⅣa in 1 isolate. Six MRSA strains were non-typeable. The isolates with SCCmecⅡ or SCCmecⅢ were resistant to multiple antibiotics. The strains harboring SCCmecⅣa or SCCmecⅤwere susceptible to all antibiotics except β-lactams. Eleven (36.7%) isolates were PVL positive. The genotypes and subgenotypes of staphylococcal chromosomal cassette mec of eleven PVL-positive MRSA were SCCmecⅡ(1 isolates), SCCmecⅢ (5 isolates), SCCmecⅣa (1 isolate), SCCmecⅤ (2 iso-Lates) non-typeable (2 isolates). Conclusions SCCmecⅡ and SCCmecⅢ are the major genotypes of MRSA in our hospital. These isolates are multi-resistant to antibiotics. The prevalence of PVL gene is higher in SCCmecⅡ- or SCCmeⅢ-positive MRSA. The isolates with SCCmecⅡ or SCCmecⅢ were resistant to multiple antibiotics.