Objective To investigate muli-leaf collimator (MLC)-defined small field output factors calculated by the treatment planning system (TPS), and to study the measuring method of small field output factors verified by 0.015 cc PinPoint ionization chamber.Methods Eight medical accelerators for intensity-modulated radiation therapy (IMRT) were investigated in Henan province, and TPS-calculated output factors for various small fields (6 cm ×6 cm,4 cm ×4 cm,3 cm ×3 cm and 2 cm ×2 cm) were compared with published values recommended by IAEA.If the relative deviation was more than ± 3％ for the 2 cm ×2 cm field size and ±2％ for the fields of 6 cm ×6 cm, 4 cm ×4 cm and 3 cm ×3 cm, which was beyond the scope of IAEA allowed, the output factors will be measured and verified using 0.015 cc PinPoint ionization chamber and Unidos electrometer.Results TPS-calculated small field output factors for eight medical accelerators were compared with published values.The relative deviation of small field output factors for five pieces of equipment, which accounted for 62.5％ of the total, met the IAEA's requirement, while the other three, which accounted for 37.5％ of the total, did not.After measuring with PinPoint ionization chamber, the results from only three pieces of equipment met minimum IAEA's requirement.Conclusions MLC-defined small field output factors calculated by TPS for some medical accelerators in Henan need to be measured and corrected using micro-ionization chamber, and the measured values could be taken as the basis of radiation treatment planning.

Objective:To compare the effects of rotational night shifts on the micturition patterns of fe-male nurses.Methods:A total of 58 nurses without lower urinary tract symptoms were recruited,who worked in the Peking University People’s Hospital during January and June in 2014.The nurses aged 20 -43 years were divided into two groups,the night-shift group (n =28)and the non-shift group (n =30).The alcohol or coffee intaking were forbidden.In the night-shift group,nurses had worked on rota-tional shifts for at least 6 months.Their average age was (26.75 ±4.11)years.In the non-shift group, nurses took regular day-time work,whose average age was (27.80 ±5.60)years.A voiding diary was kept for 7 consecutive days at the end of 6 months,starting 2 days before their night duties until 4 days after completion of their night duties.For comparison,the non-shift group with regular shifts completed a 7-day voiding diary.In the 7-day recording voiding diary,the nurses were required to have the normal in-take of liquid about 1 500 -2 000 mL/d.The frequency volume charts of nocturia,the 8-hour interval urine production and frequency were compared between the two groups.Results:Nocturia frequency was increased in the night-shift group [0.5 (0 -2.4)]compared with the non-shift group [0 (0 -2),P =0.02].The volume of nocturia was increased in the night-shift group [125 mL (0 -660 mL)]compared with the non-shift group [0 mL (0 -340 mL),P <0.01].The 8-hour interval indices showed that urine production changed with shift (P <0.01).In the consecutive 7 days,the nocturnal volume of the night-shift group increased on the day after night shift.When the night-shift nurses returned to daytime duty, the volume of urine decreased but nocturnal urine production remained high,and the frequency of noctu-ria also increased significantly (P <0.05).Compared with the 8-hour interval indices,the night-shift group’s voiding volume [(542.35 ±204.66)mL]and voiding frequency (2.24 ±0.69)were more than those of the non-shift group at the afternoon time (from 2 pm to 10 pm).During the 8 h interval night time (from 10 pm to 6 am),the volume of nocturia in the night-shift group [(309.74 ±162.74) mL]was more than that in the non-shift group [(199.38 ±153.98)mL,P =0.01];the frequency of nocturia in the night-shift group (1.31 ±0.52)was increased than that in the non-shift group (0.82 ± 0.55,P <0.01).Conclusion:The rotational shifts affect the micturition patterns of nurses who go through the night shift work,which increases the volume and frequency of the nocturia.

Objective To investigate the application effect of stone basket in ureteroscopic holmium laser lithotripsy for treatment of upper ureteral calculi. Methods The clinical data of 96 patients with upper ureteral calculi were retrospectively analyzed, all patients underwent ureteroscopic holmium laser lithotripsy. Forty-eight cases used the stone basket in the operation process (observation group), and 48 cases did not use the stone basket in the operation process (control group). The operation time, length of stay, success rate of lithotripsy, stone residual rate and incidence of postoperative complication were compared between 2 groups. Results The patients of 2 groups successfully completed surgery. There were no statistical differences in operation time, length of stay and incidence of postoperative complication between 2 groups (P>0.05). The success rate of lithotripsy in observation group was significantly higher than that in control group: 97.92% (47/48) vs. 75.00% (36/48), and the stone residual rate was significantly lower than that in control group:4.17%(2/48) vs. 18.75%(9/48), and there were statistical differences (P<0.05). Conclusions The stone basket in ureteroscopic holmium laser lithotripsy for treatment of upper ureteral calculi can thoroughly remove stones. It reduces the incidence of residual stones, does not affect the safety of the operation, and has good clinical value.

Appropriate selection and measurement of lead biomarkers of exposure are critically important for health care management purposes, public health decision making, and primary prevention synthesis. Lead is one of the neurotoxicants that seems to be involved in the etiology of psychologies. Biomarkers are generally classified into three groups: biomarkers of exposure, effect, and susceptibility.The main body compartments that store lead are the blood, soft tissues, and bone; the half-life of lead in these tissues is measured in weeks for blood, months for soft tissues, and years for bone. Within the brain, lead-induced damage in the prefrontal cerebral cortex, hippocampus, and cerebellum can lead to a variety of neurological disorders, such as brain damage, mental retardation, behavioral problems, nerve damage, and possibly Alzheimer's disease, Parkinsons disease, and schizophrenia. This paper presents an overview of biomarkers of lead exposure and discusses the neurotoxic effects of lead with regard to children and adults.
Alzheimer Disease ; chemically induced ; metabolism ; pathology ; physiopathology ; psychology ; Animals ; Behavior ; drug effects ; Biomarkers ; metabolism ; Brain ; metabolism ; pathology ; physiopathology ; Brain Diseases ; chemically induced ; pathology ; physiopathology ; Environmental Exposure ; adverse effects ; Humans ; Lead ; pharmacokinetics ; toxicity ; Lead Poisoning ; etiology ; metabolism ; pathology ; physiopathology ; psychology ; Neurotoxicity Syndromes ; etiology ; metabolism ; pathology ; physiopathology ; psychology ; Parkinson Disease, Secondary ; chemically induced ; metabolism ; pathology ; physiopathology ; psychology ; Schizophrenia ; chemically induced ; metabolism ; pathology ; physiopathology

Objective To observe vasculogenic mimicry formation difference in human hepatocellular carcinoma cell lines MHCC97-H/L with different metastatic potentials under three-dimensional culture condition,and to study extracellular matrix and adhesion molecules-related mechanism of vasculogenic mimicry.Methods Three-dimensional cell culture system of MHCC97-H/L was established to observe tubelike structures by inverted microscope.Human umbilical vein endothelial cell(HUVEC),human hepatocellular carcinoma cell line Hep3B with non-metastatic potentials and normal human hepatic cell line HL-7702 were taken as control.Gene expression profiles of MHCC97-H and MHCC97-L were detected by Oligo extracellular matrix and adhesion molecules microarray analysis.Two differentially expressed genes were verified with semi-quantitative reverse transcriptionpolymerase chain reaction(RT-PCR)and Western blot.All data were analyzed using two sample t test.Results After a 24-hour three-dimensional culture,the length of tubelike structures was(474 ± 16)mm/cm2 in MHCC97-H,which were significantly longer than(320 ±41)mm/cm2 in MHCC97-L(t =6.119,P ＜0.05).Hep3B and HL-7702 could not form tubelike structures.Compared with MHCC97-L,the expression of 7 genes were up-regulated and the expression of 3 genes were down-regulated among a total of 113 angiogenesis genes in MHCC97-H.Two of the genes with differential expressions including tenascin C and extracellular matrix protein 1 were further validated by RT-PCR and Western blot.Conclusion MHCC97-H has stronger ability to form vasculogenic mimicry than MHCC97-L,and this perhaps correlates with the differential expression of certain extracellular matrix and adhesion molecules-related genes in MHCC97-H.

To observe the effects of early intervention with effective components from a Chinese herbal formula (Huannao Yicong formula, HNYCF) on behavior and related indicators of cholinergic system in β-amyloid precursor protein (APP) transgenic mice.

Hearing Loss, Sensorineural ; genetics ; Humans

Background Pupillary light reflex has been widely used in the diagnosis and evaluation of visual system and nervous system diseases.However,in animal experiments,functional evaluation of the visual system and nervous system needs more advanced technology and are affected by many factors.Objective This study was to explore the use of the dynamic pupillometer in evaluating pupillary light reflex and to discuss the influence of brightness of stimulate on relevant curve parameters in C57BL/6 mouse.Methods Ten healthy SPF male C57BL/6 mice were collected in this experiment.White light of five luminance levels (2,8,32,128,256 cd/m2) was used to stimulate the mice following a 2-hour dark adaptation.The stimulation was given at the 60-second intervals,for a duration of 100 ms at every stimulation.An infrared camera and video capture card were used to capture digital images during the measuring process in a scotopic environment,at a speed of 60 frames per second.Measuring outcome was saved in the*.AVI format.A software that was developed by our group was used to determine pupil diameter and output pupillary light reflex curve offline.Pupil initial diameter (R1),constriction amplitude (CA),constriction velocity (CV),latency (T1),time for maximum velocity (T2),time for maximum constriction (T3),time for maximun con-striction to 10.1％ R1 re-dilation (RT)and re-dilation velocity (RV)were assessed,and the correlations between luminosity and measuring parameters were analyzed using the Spearman rank correlation.The use of animals followed the Regulations for thd Administration of Affairs Concerning Experimental Animals by State Science and Technology Commission.Results R1 values showed no statistically significant difference among the 5 different luminosity groups(F=1.117,P=0.361).A positive linear correlation was found between stimulating luminosity and CA(r=0.508,P＜ 0.01),but negative correlations were seen between stimulating luminosity and CV or RV (r=-0.625,-0.609,P＜0.01).T1 and T2 values in the 5 different luminosity groups were not statistically significant (F =0.202,P =0.936 ; F =1.584,P =0.195).The different levels of stimulating luminosity showed positive linear correlations with T3 and RT values (r =0.791,0.609,P＜ 0.01).Conclusions The dynamic pupillometer can quantitatively measure the pupillary light reflex of C57BL/6 mice.The pupillary light reflex dynamic curve parameters of mouse were affected by stimulus luminosity levels.These outcomes offer a basis for the application of the dynamic pupillometer system for measuring pupillary light reflex in animal models.

To investigate the protective effect of preconditioning with hyperoside ( Hyp) against myocardial ischemia-reperfusion injury (MIRI) in rats and the role of PI3K/Akt signaling pathway. MIRI was established by ligation of left anterior descending coronary artery for 30 min followed by reperfusion for 120 min in rats. Male SD rats were randomly divided into five groups: sham group,model group (MIRI),Hyp preconditioning group(Hyp), Hyp preconditioning + LY294002 (a PI3K/Akt signaling pathway inhibitor) group (Hyp + LY), and LY294002 group (LY). At the end of reperfusion, hemodynamic parameters were recorded as left ventricular systolic pressure (LVSP) , left ventricular end-diastolic pressure ( LVEDP) and maximal rate of increase and decrease of left ventricular pressure (± dP/dt(max)). Myocardial infaret size, the oxidative stress markers, myocardial enzymes indicators and inflammatory factors were also analyzed. The expressions of Akt, p-Akt, Bax and Bcl-2 proteins was detected by using Western blot method. The results showed that Hyp preconditioning remarkably improved cardiac constriction and relaxation function, reduced myocardial infarct size and enhanced the activities of oxidative stress markers about correlated to MIRI, such as superoxide dismutase (SOD), catalase (CAT) and glutathione-peroxidase (GSH-Px) and decreased the contents of malondialdehyde (MDA) as compared with MIRI group. Simultaneouly, the levels of myocardial enzymes, i. e. creatine kinase ( CK) and creatine kinase MB isoenzyme (CK-MB), and inflammatory factors, for instance tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were decreased. Hyp pretreatment apparently restrained myocardial apoptosis as evidenced by decreasing the level of Bax expression, increasing the levels of phosphorylation of Akt and Bcl-2 expression. These effects were inhibited by LY294002, a blocker of PI3K/Akt signaling pathway. These findings indicated that the cardioprotection of Hyp preconditioning against MIRI may be related to activating PI3K/Akt signaling pathway, upregulating the expression of BCL-2 protein and down-regulating the expression of Bax protein.
Animals ; Creatine Kinase ; genetics ; metabolism ; Drugs, Chinese Herbal ; administration & dosage ; Heart ; drug effects ; Humans ; Interleukin-6 ; genetics ; metabolism ; Ischemic Preconditioning, Myocardial ; Male ; Malondialdehyde ; metabolism ; Myocardial Reperfusion Injury ; drug therapy ; enzymology ; genetics ; prevention & control ; Phosphatidylinositol 3-Kinases ; genetics ; metabolism ; Proto-Oncogene Proteins c-akt ; genetics ; metabolism ; Quercetin ; administration & dosage ; analogs & derivatives ; Rats ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein ; genetics ; metabolism

To investigate the effects and potential mechanisms of hyperoside (Hyp) on the vascular endothelium function in middle cerebral artery (MCA) ex vivo in rats. Isolated arterial segments from MCAs of rats were used for surveying vasomotoricity in a pressurized chamber. Transmembrane potential was recorded by using glass microelectrodes to evaluate hyperpolarization. Hyp (1 x 10(-6)-1 x 10(-4) mol . L-1) was utilized to observe the effect on 1 x 10(-7) mol . L-1 U46619-preconstricted MCA in rats. The results showed that 1 x 10(-6)-1 x 10(-4) mol . L-1 Hyp significantly induced concentration-dependent vasodilatation and hyperpolarization, leading to the maximal diastolic ratio of (73. 2 ± 6. 1)% and maximal changes in membrane potentials of (-13. 2 ± 2. 2) mV. Hyp still elicited vasorelaxation and hyperpolarization by removal of endothelium in MCA of rat, which was notably attenuated as compared with vascular endothelium-intact group (P <0. 01). In the MCAs preconstricted by U46619 (1 x 10(-7) mol . L-1), Hyp (1 x 10(-6)-1 x 10(-4) mol . L-1) produced concentration-dependent vasorelaxation and hyperpolarizition that were partially attenuated by 3 x 10(-5) mol . L-1 L-NAME(a NOS inhibitor) plus 1 x 10(-5) mol . L-1 PGI2 ,(a synthetase inhibitor). The residual effects were further decreased by 1 x 10(-3) mol . L-1 TEA (an inhibitor of Ca2+-activated potassium channel) or 1 x 10(-5) mol . L-1 PPG (a blocker of endogenous H2S synthese-CSE). Similarly, 1 x 10(-5)-1 x 10(-3) mol . L-1 NaHS (a donor of exogenous H2S) or 1 x 10(-5)-1 x 10(-3) mol . L-1 L-Cys (the substrate of endogenous H2S synthesis) obviously evoked dose-dependent vasodilatation and hyperpolarization of MCA in rats. These findings indicated that Hyp may induce endothelium-dependent and endothelium-independent responses. And the endothelium-dependent vasodilatation may be related to the increases of endogenous H2S that has been promoted Hyp in the endotheliocyte of MCAs, and activated Kca and opening of Kca channels, resulting in the hyperpolarization of vascular smooth muscle cell membrane and subsequent reduction of Ca2+ influx and vasodilation.
Animals ; Endothelium, Vascular ; drug effects ; Enzyme Inhibitors ; pharmacology ; Female ; Male ; Middle Cerebral Artery ; Muscle, Smooth, Vascular ; drug effects ; Nitric Oxide ; metabolism ; Potassium Channels ; metabolism ; Quercetin ; analogs & derivatives ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Sulfides ; metabolism ; Vasodilation ; drug effects ; Vasodilator Agents ; pharmacology