Improving the activity of creatinase from Alcaligenes sp. KS-85 through semi-rational design / 生物工程学报

Creatinine levels in biological fluids are important indicators for the clinical evaluation of renal function. Creatinase (CRE, EC3.5.3.3) is one of the key enzymes in the enzymatic measurement of creatinine concentration, and it is also the rate-limiting enzyme in the whole enzymatic cascade system. The poor catalytic activity of CRE severely limits its clinical and industrial applications. To address this issue, a semi-rational design is applied to increase the activity of a creatinase from Alcaligenes sp. KS-85 (Al-CRE). By high-throughput screen of saturation mutagenesis libraries on the selected hotspot mutations, multiple variant enzymes with increased activity are obtained. The five-point best variant enzyme (I304L/F395V/K351V/Y63S/Q88A) were further obtained by recombine the improved mutations sites that to showed a 2.18-fold increased specific activity. Additionally, structure analysis is conducted to understand the mechanism of the activity change. This study paves the way for a better practical application of creatinase and may help further understand its catalytic mechanism.

The effects of photoperiodism and exposure to bisphenol A on hepatic lipid metabolism in female mice / 中国职业医学

OBJECTIVE: To analyze the effects and the underlying mechanisms of photoperiodism and exposure to bisphenol A(BPA) on hepatic lipid metabolism in female mice. METHODS: A 2×2 factorial design was used. The photoperiod factor was set to fixed and shifted photoperiod, and the BPA factor was set to BPA exposure(BPA group) and non-exposure(control group). Specific pathogen free female C57 BL/6 J mice were randomly divided into four groups: fixed photoperiod control group, shifted photoperiod control group, fixed photoperiod BPA group, and shifted photoperiod BPA group, with eight rats in each group. The fixed photoperiod mice received a 12 ∶12 hours light-dark cycle, and the shifted photoperiod mice experienced reversed light-dark cycle once a week. Mice in BPA group were administered a dose of BPA 50 μg/kg body weigh by gavage, while mice in control group were given a equal volume of corn oil, once per day, five days per week for 12 weeks. The body weight of mice was measured during the experiment. After 12 weeks, all mice in each group were sacrificed. Plasma was collected and the levels of biochemical parameters were measured. Liver tissues were separated for examination of lipid deposition using oil red O and hematoxylin-eosin staining, and plasma triglyceride levels were measured. Real-time fluorescence quantitative polymerase chain reaction was used to detect the mRNA relative expression of genes of fat metabolism in liver tissues. RESULTS: At the end of the experiment, the body weights of mice were higher than that before the experiment(all P<0.05), but there was no statistically significant difference in body weights among the four groups(all P>0.05). The levels of plasma glucose, triglyceride and activity of alanine aminotransferase were higher in shifted photoperiod mice than that in the fixed photoperiod mice(all P<0.05). The plasma aspartate transaminase level was higher in BAP group than that in control group(P<0.01). The area of lipid staining in hepatic tissue was larger in the shifted photoperiod control group, fixed photoperiod BPA group and shifted photoperiod BPA group(all P<0.05), and hepatic lipid droplets aggregation was increased in these three groups compared with the fixed photoperiod control group. The mRNA relative expression of acetyl-coenzyme A carboxylase alpha(Acaca) was higher in the fixed photoperiod BPA and shifted photoperiod control groups(all P<0.05), compared with the fixed photoperiod control group. The relative expression of Acaca mRNA was lower in the shifted photoperiod BPA group than that in the fixed photoperiod BPA group(P<0.05). The mRNA relative expression of sterol regulatory element binding protein(Srebp) 1 and Srebp2 were significantly higher in the BPA group than that in the control group(all P<0.05). CONCLUSION: Both the single shifted photoperiod or BPA exposure can increase hepatic lipid deposition in female mice. The mechanism may be related to up-regulation of the mRNA expression of Acaca, Srebp1 and Srebp2. The shifted photoperiod in combination of BPA exposure has an antagonistic effect on the expression of Acaca mRNA in liver tissues of female mice.

A new antiviral isoquinoline alkaloid from Thalictrum glandulosissimum / 中国中药杂志

A new isoquinoline alkaloid(1) has been isolated from the whole plant of Thalictrum glandulosissimum by using various chromatographic techniques, including silica gel, sephadex, MCI-gel resin, and RP-HPLC, and its structure was determined as 1-(6-hydroxy-7-methylisoquinolin-1-yl) ethantone by physicochemical properties and spectroscopic data. This compound was evaluated for anti-tobacco mosaic virus(TMV) activity. The results showed that it had prominent anti-TMV activity with inhibition rates of 28.4%. This rate was closed to that of positive control.

A new isobenzofuranone derivative from Chaenomeles sinensis and its antibacterial activity / 中国中药杂志

A new isobenzofuranone derivative was isolated from Chaenomeles sinensis by using various chromatographic techniques,including silica gel,Sephadex LH-20,MCI-gel resin and RP-HPLC. This compound was determined as 2,2-dimethyl-5-( 2-oxopropyl)-2 H-furo[3,4-h]chromen-7( 9 H)-one( 1) by NMR,MS,IR and UV spectra,and was also evaluated for its antibacterial activity. The results showed that it showed prominent antibacterial activity with MIC90 value of( 53. 7±4. 5) mg·L-1 for methicillin resistant Staphylococcus aureus( MRSA) strain. This value is close to that of levofloxacin [with MIC90 value( 50. 2± 4. 2) mg·L-1].

A new isoflavone derivative from Rosa Damascena and its antibacterial activity / 中国中药杂志

A new isoflavone derivative was isolated from Rosa damascena by using various chromatographic techniques including silica gel, Sephadex LH-20, and preparative RP-HPLC separation. Its structure was identified as 4'-hydroxy-7-(3-hydroxypropanoyl)-6-methoxy-isoflavone using combined examinations of their UV, IR, MS, and NMR spectroscopic data. Biological activity test showed that this compound showed prominent antibacterial activity with MIC₉₀ value of (46±4) mg·L⁻¹ for methicillin resistant Staphylococcus aureus(MRSA) strain. This value is close to that of levofloxacin [with MIC₉₀ value (53±5) mg·L⁻¹].

A new naphthaldehyde derivative from Comastoma pulmonarium and its anti-tobacco mosaic virus (anti-TMV) activity / 中国中药杂志

A new naphthaldehyde derivative has been isolated from Comastoma pulmonarium by using various chromatographic techniques, including silica gel, Sephadex LH-20, MCI-gel resin and RP-HPLC. This compounds was determined as 5-methoxy-2-methyl-7-(2-oxopropyl)naphthalene-1-carbaldehyde(1) by NMR, MS, IR and UV spectra. This compound was also evaluated for its anti-tobacco mosaic virus (anti-TMV) activity. The result showed that it showed high anti-TMV activity with inhibition rate of 32.8%. The inhibition rate is close to that of positive control (ningnanmycin).

A new isobenzofuranone derivative from Phlomis betonicoides and its antibacterial activity / 中国中药杂志

A new isobenzofuranone derivative has been isolated from Phlomis betonicoides by using various chromatographic techniques, including silica gel, Sephadex LH-20, MCI-gel resin and RP-HPLC. This compound was determined as 5-(3-hydroxypropyl)-2,2-dimethyl-2-furo[3,4-]chromen-7(9)-one (1) by NMR, MS, IR and UV spectroscopic data. Compound 1 showed potent antibacterial activity with an MIC₉₀ value of (58.4 ± 4.2) mg·L⁻¹ for methicillin resistant Staphylococcus aureus (MRSA) strain [levofloxacin as a control with MIC₉₀ value of (52.8±4.6) mg·L⁻¹].

A new naphthalene derivative from Aloe vera and its antibacterial activity / 中国中药杂志

A new naphthalene derivative has been isolated from Aloe vera by using various chromatographic techniques, including silica gel, sephadex, MCI-gel resin, and RP-HPLC. The new compound was determined as 3-hydroxy-1-(1,7-dihydroxy-3,6-dimethoxynaphthalen-2-yl)propan-1-one (1). In the biological activity assay, compound 1 disglayed prominent antibacterial activity with a MIC90 value of (48±4) mg•L⁻¹ for methicillin resistant Staphylococcus aureus (MRSA) strain which was stronger than that of the positive control levofloxacin with a MIC90 value (58±5) mg•L⁻¹.

Fractalkine overexpression suppresses tau pathology in a mouse model of tauopathy.

Alzheimer's disease is characterized by amyloid plaques, neurofibrillary tangles, glial activation, and neurodegeneration. In mouse models, inflammatory activation of microglia accelerates tau pathology. The chemokine fractalkine serves as an endogenous neuronal modulator to quell microglial activation. Experiments with fractalkine receptor null mice suggest that fractalkine signaling diminishes tau pathology, but exacerbates amyloid pathology. Consistent with this outcome, we report here that soluble fractalkine overexpression using adeno-associated viral vectors significantly reduced tau pathology in the rTg4510 mouse model of tau deposition. Furthermore, this treatment reduced microglial activation and appeared to prevent neurodegeneration normally found in this model. However, in contrast to studies with fractalkine receptor null mice, parallel studies in an APP/PS1 model found no effect of increased fractalkine signaling on amyloid deposition. These data argue that agonism at fractalkine receptors might be an excellent target for therapeutic intervention in tauopathies, including those associated with amyloid deposition.

Analysis of 86 fatal motorcycle frontal crashes in Chongqing, China / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To analyze the injuries of motorcyclists involved in fatal motorcycle frontal crashes.</p><p><b>METHODS</b>A survey group involving multi-discipline experts was built to randomly collect data on fatal motorcycle frontal collision accidents that occurred in Chongqing during 2006-2010. The sampled information included medical or autopsy reports, blood alcohol concentration (BAC) level, helmet use, accident witness, field sketch as well as field photos. The motorcyclist injuries were scored according to the Abbreviated Injury Scale (AIS) 2005. The involved riders with a BAC level larger than or equal to 20 mg/ml were attributed to alcohol use. Data were processed statistically with nonparametric test via software SPSS 11.0.</p><p><b>RESULTS</b>A total of 86 fatal motorcycle frontal crashes were sampled and further analyzed. The age of motorcyclists enrolled in this investigation showed nominal distribution and the middle-aged (30-39 years) occupied the highest percentage of fatalities. There were only 14 motorcyclists (16.3%) wearing helmets at the moment of collision. And 12.8% of these motorcyclist crashes were attributable to alcohol use. Impact injury was the main fatal cause, accounting for 72% of motorcyclist deaths, followed by tumbling injury (26%) and run-over (2%). Respectively 84%, 22% and 19% of motorcyclists who sustained head, chest and abdominal trauma died. Extremity injury was the most frequently observed injury type.</p><p><b>CONCLUSIONS</b>This investigation is helpful to build accident prevention programs and develop protection devices which may effectively mitigate injuries and prevent deaths following motorcycle frontal collision accidents. Further investigations on motorcycle collision accidents are still needed.</p>

Effects of low frequency resonance on physiological function in rats / 医用生物力学

Objective To study the effect of continuous low frequency resonance on blood pressure, heart rate, breath rate and body temperature of the rat so as to provide basic data for the study of organs’ resonance injury and its reaction. Method Thirty two SD rats were divided into four groups randomly: false vibration group, 3 Hz vibration group, 6 Hz vibration group and 21 Hz vibration group. Femoral artery intubatton was given after anaesthesia with 1.5% sodium pentobarbital. All the rats were fastened on their back on the vibration platform staying calmly for 30 min. Then the vibration groups were given sine wave vibration with 5 mm amplitude(p-p), while the blood pressure, heart rate, breath rate and body temperature of the rats were measured at 0, 1, 3, 5, 10, 30, 60, 120, 180, 240, 300 and 360 min. The above physiological data were also observed in false vibration group at corresponding time. Results Continuous low frequency resonance could cause the blood pressure, heart rate, breath rate of the rat to rise rapidly after 1 min of vibration, and to reach the maximum value after 1 min to 3 min of vibration, and then to descend gradually and to be lower than the normal value after 30 min of vibration. The body temperature of the rat did not change at the beginning of vibration, but descended gradually after 10 min of vibration. At the beginning of vibration, the effect of 6 Hz resonance on blood pressure, heart rate, breath rate was dominating, while at the later stage, 3 Hz resonance was dominating. But the effect of the two frequencies on body temperature was accordant. Conclusions Continuous low frequency resonance can cause the blood pressure, heart rate, breath rate of the rat to rise rapidly at the beginning of vibration and then to descend gradually, and it can also depress the ability of body temperature regulation in rats.

The value of plasma pro-gastrin-releasing peptide, cytokeratin 19-fragments and carcinoembryonic antigen in patients with lung cancer / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To evaluate the value of plasma ProGRP, CYFRA 21-1 and CEA in patients with lung cancer.</p><p><b>METHODS</b>The levels of plasma ProGRP, CYFRA 21-1 and CEA were detected in 85 healthy control, 49 benign lung diseases and 143 lung neoplasms. The levels of ProGRP in the patients with SCLC was monitored.</p><p><b>RESULTS</b>The level of plasma ProGRP in SCLC (M 179.1 ng/ml) was significantly higher than adenocarcinoma (M 35.3 ng/ml), squamous-cell carcinoma (M 33.3 ng/ml), healthy control (M 35.6 ng/m) and benign lung diseases (M 33.3 ng/m), P < 0.001. The sensitivity and specificity for diagnosing SCLC by ProGRP were 60.6% and 95.0% respectively. In the effective treatment group, ProGRP reduced 45.9%, in the progression group, ProGRP increased 103.1%, P < 0.05. The level of CEA in the metastatic adenocarcinoma (M 10.22 ng/ml) was significantly higher than non-metastatic adenocarcinoma (M 3.85 ng/ml) and squamous cell carcinoma (M 2.56 ng/ml) (P < 0.01).</p><p><b>CONCLUSION</b>The plasma ProGRP is a good indicator for diagnosing and evaluating cure effect in SCLC; the high expression of CEA is related to the metastatic adenocarcinoma.</p>

Establishment of the model of motorcyclist ejection injury / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To establish the device and model of motorcyclist ejection injury.</p><p><b>METHODS</b>Based on our laboratory devices, a motorcyclist ejection injury simulation system was developed. A total of 18 pigs were approved by the local animal experimentation and ethics committee to serve as the motorcyclist substitutes. In this ejection motion, the animal rode freely at the motor driver seat and was straightly accelerated by means of our custom motorcyclist ejection injury simulation system. When it was speeded up to the preset velocity (v equal to 30, 40 or 50 km/h) at the preset position, the animal was ejected forward. Pathological and dynamic analyses were conducted, accompanied with the high-speed photograph, acceleration/velocity signal test, gross observation and light microscope examination as well as the abbreviated injury score-injury severity score (AIS-ISS) scale.</p><p><b>RESULTS</b>The high-speed photograph indicated that during the ejection procedure the motorcycle was first arrested and decelerated suddenly, and then the motorcycle driver was ejected forward, accompanied with the rotation motion in the air. Finally, the head, shoulder and thorax of the ejected animal impacted directly on the hard ground. Varying degrees of injury focusing on the liver, heart, lung and spleen were found. There existed a significant positive correlation between ISS and the ejection velocity of the motorcycle drivers (ISS equal to 16.7+/-2.9 for 30 km/h, 25.0+/-0.0 for 40 km/h and 37.3+/-1.0 for 50 km/h). The detailed injury characteristics were as follows: for the mildly injured animals, there were interlobar gaps or leaf gaps and lobar surface blood coagulation blocks in the liver, and mild lung hemorrhage; for the severely injured animals, there were liver comminuted laceration, moderate lung hemorrhage and heart injury. Animals suffering from the most severe injuries died half an hour later.</p><p><b>CONCLUSION</b>The new injury model stated in this paper has a high stability and good repeatability, and is likely to be helpful to deeply investigate the injury mechanisms and protection countermeasures of motorcyclist ejection injury.</p>

Controlled continuous curvilinear capsulorhexis in short axial length and shallow anterior chamber eyes / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the efficacy of controlled continuous curvilinear capsulorhexis(CCC) technique in short axial length and shallow anterior chamber eyes.METHODS:Sixty-eight patients(68 eyes) with short axial length and shallow anterior chamber were included.The routine CCC technique was used in 32 cases (32 eyes) and controlled CCC technique was used in 36 cases (36 eyes).The success rate and complication were compared between two groups. RESULTS:The success rate of the routine technique group and controlled technique group was 53. 13% and 86.11% respectively. Incomplete CCC leading to posterior capsule tears was 9.38% and zero in two groups respectively.CONCLUSION: Controlled CCC technique can increase the success rate and reduce complications in short axial length and shallow anterior chamber eyes.KEYWORDS:phacoemulsification; continuous curvilinear capsulorhexis; complication

Effects of indole-3-carbinol on the outcome of tumor and the changes of anti-oxidative system in null mice grafted with nasopharyngeal carcinoma / 中华预防医学杂志

<p><b>OBJECTIVE</b>To observe the effects of indole-3-carbinol (I3C) on the outcome of the tumor as well as the changes of the anti-oxidative system in null mice grafted with nasopharyngeal carcinoma.</p><p><b>METHODS</b>48 BALB/c null mice were divided by means of random number table into control group (0.5% sodium carboxyl methyl cellulose), low dosage (0.02 g/kg), middle dosage (0.1 g/kg) and high dosage (0.5 g/kg) of I3C. The mice were administered with different solutions by gavage for 10 days before CNE1 cells were inoculated subcutaneously into the back (near the armpit) of the nude mice, then the solutions were continually administered by gavage. The tumor volume was measured and the tumor inhibitory rate was calculated. The level of malondialdehyde (MDA), the activity of superoxide dismutases (SOD), the activity of glutathione peroxidase (GSHPx) and the expression of cleaved caspase-3 were determined on the 31th day of the study.</p><p><b>RESULTS</b>I3C could reduce the tumor volume [the tumor volumes of the control group, the middle dosage group and the high dosage group were (4.13 +/- 0.53) x 10(-6) m(3), (3.14 +/- 0.71) x 10(-6) m(3), (2.72 +/- 0.29) x 10(-6) m(3)], as compared with the control, the shrinkage of tumor volume of the middle dosage group and the high dosage group were significant (the t valued at 0.990 and 1.510, P < 0.01). The tumor inhibitory rates of 3 groups were 3.8%, 20.5% and 34.9%, respectively. The contents of MDA in the tumor tissue tended to decrease [the values of control group, the low dosage group, the middle dosage group and the high dosage group were (31.29 +/- 2.51) x 10(-6) mol/L, (30.12 +/- 2.37) x 10(-6) mol/L, (23.32 +/- 1.93) x 10(-6) mol/L, (16.45 +/- 1.43) x 10(-6) mol/L] (F = 98.752, P < 0.01), and that of the high and the middle dosage group could obviously be reduced (t = 8.970, 14.840, P < 0.01) as compared with the control. The activity of SOD seemed to be elevated according to the increase of I3C dosage [the values were (387.24 +/- 23.16) x 10(3) U/L, (399.37 +/- 34.45) x 10(3) U/L, (431.63 +/- 31.24) x 10(3) U/L, (476.45 +/- 44.67) x 10(3) U/L] (F = 53.444, P < 0.01). When compared with the control, the SOD activity of the middle and the high dosage group be obviously increased (t = 44.390, 89.210, P < 0.01). I3C could also elevate the GSHPx activity [the GSHPx values of the four groups were (226.98 +/- 18.35) x 10(3) U/L, (234.65 +/- 15.59) x 10(3) U/L, (247.72 +/- 22.73) x 10(3) U/L, (300.37 +/- 26.02) x 10(3) U/L] (F = 25.916, P < 0.01). The GSHPx of the high dosage group was enhanced remarkable (t = 73.390, P < 0.01) as compared with the control. The expression of cleaved caspase-3 (relative molecular weight = 19 000 000) seemed to be elevated according to the increase of I3C dosage and the relative expression levels of which were 0.87 +/- 0.01, 0.97 +/- 0.01, 1.02 +/- 0.06 and 1.14 +/- 0.02 (F = 39.864, P < 0.01). When compared with the control, the elevation of this kind of cleaved caspase-3 was considered statistical significant (the t values were 0.100, 0.086 and 0.303, respectively, P < 0.05). When I3C dosage increased, the expression of cleaved caspase-3 (relative molecular weight = 17 000 000) seemed to increased too [the relative expression levels of which were 0.00 +/- 0.00, 0.05 +/- 0.02, 0.11 +/- 0.02, 0.20 +/- 0.02 (F = 56.629, P < 0.01)], and the increase of this kind of cleaved caspase-3 was esteemed significantly as compared with those of the control (the t valued at 0.046, 0.103 and 0.193, respectively, P < 0.05). Linear correlate analysis showed that the correlation coefficients between the shrinkage of tumor volume and the expression of the two kinds of cleaved caspase-3 protein was -0.732 (t = 3.404, P < 0.01) and -0.901 (t = 6.642, P < 0.01).</p><p><b>CONCLUSION</b>I3C could reduce the growth of tumor, the mechanism underlie it could be related to the decrease of the content of MDA as well as the elevated levels of SOD, GSHPx, and perhaps could be related to the apoptosis transduced by cleaved caspase-3.</p>

Research on brain tissue mechanical Style in brain model deceleration Impact / 医用生物力学

Objective to research the mechanical style(compressive or tensile force)of the key site of brain tissue in brain deceleration impact.Method a transparent physical brain model with air bubbles was built and loaded on an upright brain decaler ation impacting expedmentel platform.Then,the moveable platform was made a free fall from a height of 400mm and impacted on the fixed platform,and the whole deceleration impacting process was recorded by a high-speed video camera.Using the serial pictures analyzing Software,the length change of the long ads(vertical to the impacting direction)and the short axis(in the impacting di-rection)of the air bubbles were analyzed and calculated.Result the length change of the long axis of air bub-ble with in site coup was smallerthan the absolute value of that of the short axis;while with the air bubble in the contrecoup site,the length change of the long axis was bigger than the absolute value of the short axis.Conclusions the results showed that the air bubble in the coup site mainly suffered from the tensile force vertical to the impacting direction and the air bubble in the contrecoup site mainly suffered from the compres-sive force in the impacting direction.Since the propeny of tensile resistance of the brain tissue is inferior to the property of compressive resistance of the brain tissue, the injury is often easier to occur in the contrecoup site than in coup site. The results were of significance to the research of biomechanical mechanism, diagnosis and prevention of the brain deceleration impacting injury.

Research on brain tissue mechanical Style in brain model deceleration Impact / 医用生物力学

Objective to research the mechanical style(compressive or tensile force)of the key site of brain tissue in brain deceleration impact.Method a transparent physical brain model with air bubbles was built and loaded on an upright brain decaler ation impacting expedmentel platform.Then,the moveable platform was made a free fall from a height of 400mm and impacted on the fixed platform,and the whole deceleration impacting process was recorded by a high-speed video camera.Using the serial pictures analyzing Software,the length change of the long ads(vertical to the impacting direction)and the short axis(in the impacting di-rection)of the air bubbles were analyzed and calculated.Result the length change of the long axis of air bub-ble with in site coup was smallerthan the absolute value of that of the short axis;while with the air bubble in the contrecoup site,the length change of the long axis was bigger than the absolute value of the short axis.Conclusions the results showed that the air bubble in the coup site mainly suffered from the tensile force vertical to the impacting direction and the air bubble in the contrecoup site mainly suffered from the compres-sive force in the impacting direction.Since the propeny of tensile resistance of the brain tissue is inferior to the property of compressive resistance of the brain tissue, the injury is often easier to occur in the contrecoup site than in coup site. The results were of significance to the research of biomechanical mechanism, diagnosis and prevention of the brain deceleration impacting injury.

Aspheric topographical features of the anterior surface of the human crystalline lens / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the topography of the anterior surface of the human crystalline lens. ·METHODS: A Non-contact three-coodinate measuring system was utilized to scan the anterior surfaces of 8 human eye lenses in vitro. Acquired data were processed and computer models of the anterior lens surfaces were made using the program (Surfacer v 10.0). The to-pography of the anterior lens surfaces were established. Radii of curvature were measured at preset spots over the lens surfaces and two way analysis of variance was performed. The data were analysed to determine whether the radius of curvature varied systematically with the position on the lens surface from which the measurement was made. Lens surface asymmetric index (LSAI) was defined and calculated. The vertical and horizontal meridians of the modeled lens were calculated, and the best curve fit to any conic section was determined. ·RESULTS: The topography of the anterior lens surface indicated that the central zone (the central radius of curvature is (9.09±0.80)mm was steeper than that of the peripheral zone(17.05±2.20)mm. Two way analysis of variance of the radii of curvature at preset spots over the lens surfaces showed that the differences were statistically significant (P ＜ 0.05). Curve regression of radii of curvature at preset spots and their distances to the surface center revealed that the correlation of them was the third power function. LSAI increased steadily from the lens surface center(0.013±0.005) to the periphery(0.184± 0.065). The dots on the horizontal and vertical meridians were fit to four kinds of curves, and the determinate coefficient of hyperbola fit were the largest (0.9989-0.9999). ·CONCLUSION: The anterior lens surface is imperfectly rotational symmetric. Moreover, the nearer to the center, the more rotational symmetric it is. Radii of curvature increase nonlinearly from the surface center to the periphery. Anterior lens surface is typically hyperbolic.

Isolation and Resistance of Acinetobacter calcoaceticus-baumannii in Hospital: A 7-Year Surveillance Study / 中华医院感染学杂志

OBJECTIVE To study the isolation and resistance tendency of Acinetobacter calcoaceticus-baumannii to antimicrobial agents from 1998 to 2004 to provide valuable data for infection prevention and therapy. METHODS We reviewed the isolation rates,distribution in clinical specimens and wards,and the resistance rates of(A.calcoaceticus-baumannii)to 14 kinds of antimicrobial agents from 1998 to 2004. RESULTS There was an increasing tendency of isolation rates of A.calcoaceticus-baumannii every year,which was 0.18% in 1998 but 1.48% in 2004.In the seven years,there was the highest isolation rate of 70.58% in specimens from respiratory tract,the next was from the urine(9.42%),and blood(4.63%).Concerning the wards distribution,ICU had the highest rate of 47.28%.In 1998,A.calcoaceticus-baumannii had resistance rates more than 50% only to one kind of antimicrobial agents(aztreonam),but in 2004,it had increased to thirteen kinds(except cefoperazone/sulbactam).About the fourteen kinds of antimicrobial agents we inspected,that were increased in their resistance rate.The highest increasing of resistance rate was ceftazidime from 11.1% in 1998 to 88.9% in 2004,the imipenem was second for 0.0% to 64.8%,and the third was sulfamethoxazole/trimethoprim form 0.0% to 64.0%,while there still was an increasing resistance tendency to them. CONCLUSIONS The clinical isolation rate of A.calcoaceticus-baumannii is increasing,and it has higher resistance rates to many antimicrobial agents as well as an increasing resistance tendency to relatively susceptive antimicrobial agents every year.So physicians should prescribe on the basis of antimicrobial agents susceptibility tests in vitro.