Study on skeletal muscle mass of 1 836 check-up adults and its association with age in Qiqihar / 中华预防医学杂志

<p><b>OBJECTIVE</b>To analyze the correlation between skeletal muscle mass and age among check-up adults.</p><p><b>METHODS</b>The study objects were those who aged 18-87 years old and came to a city hospital of Qiqihar for health examination from December, 2013 to September, 2014, excepted those with coronary heart disease, infectious disease, endocrine system disease, hypertension, anemia, cancer, liver disease, kidney disease and those carrying with heart pacemaker. A total of 1 836 respondents were finally enrolled into analysis. Appendicular Skeletal Muscle (ASM) was measured by a Body Composition Analyzer, and relative skeletal muscle index (RSMI) was calculated. The relationship among ASM, RSMI and age was assessed by linear regression analysis. The difference of height, weight, BMI, waist-hip-ratio (WHR), total muscle mass and percentage of body fat between genders were tested by t-test. The difference of ASM and total skeletal muscle mass between genders and among age groups was tested by multi-factor variance analysis. The difference of the muscle decline between genders was compared by Chi-square test.</p><p><b>RESULTS</b>The total muscle mass in males was (52.22 ± 6.65) kg, which was significantly higher than that in females ((38.05 ± 4.39) kg) (t=28.20, P<0.001). ASM in 18-29, 30-39, 40-49, 50-59, 60-69, 70-87 years was (24.64 ± 3.23), (24.00 ± 3.12), (24.35 ± 3.03), (23.33 ± 2.97), (22.54 ± 2.91) and (21.40 ± 3.36) kg (F=16.12, P<0.001) in males, respectively, and (16.48 ± 3.14), (16.72 ± 1.93), (16.75 ± 1.93), (16.84 ± 2.28), (16.52 ± 2.35) and(14.70 ± 2.37)kg (F=4.38, P=0.001) in females, respectively. ASM in males ((23.72 ± 3.16) kg) was higher than that in females ((16.65 ± 2.25) kg) (t=55.97, P<0.001). There was a negative correlation between age and ASM in males after 50 years old, the regression equation was y=28.31-0.09x (P<0.001). While a negative correlation between age and ASM in females occurred after 60 years old, the regression equation was y=27.69-0.18x (P<0.001). The prevalence of low ASM was 16.85% (124/736) in females, which was significantly higher than that in males (8.73%, 96/1 100) (χ(2)=27.57, P<0.001).</p><p><b>CONCLUSION</b>A negative correlation was found between age and ASM in males after 50 years old and in females after 60 years old. The prevalence of low RSMI in females was significantly higher than that in males.</p>

Effects of Chronic Manganism on Hearing and Cochlear Cells in Rats / 听力学及言语疾病杂志

Objective To study the effects of chronic manganism on hearing and cochlear cells in rats by using animal model of chronic manganism .Methods Sixty adult SD rats were randomly divided into Mn - exposed and controlgroups.RatsweretreatedwithMnCl24H2O(100mg·kg -1·d-1)ordeionizedwaterbygastricperfusion, lasted for 12 weeks .The Mn concentration in peripheral blood was measured respectively at 4 weeks ,8 weeks and 12 weeks after treatment .At 12 weeks after treatment ,the auditory brainstem response was recorded ,the hair cells morphology and counting were examined by stretched preparation of basilar membrane stained with FITC -phalloi-din ,and the spiral ganglion cells morphology and counting were studied by HE staining ,the ultrastructure changes of hair cells and spiral ganglion cells were detected by transmission electron microscopy .Results The blood Mn concentration increased gradually with time after treatment .ABR thresholds at 4 ,8 ,16 ,24 and 32 kHz were sig-nificantly increased at 12 weeks after treatment ,especially in the high-frequency range .Morphological study at 12 weeks after treatment showed loss of outer hair cells ,mainly in the basal turn of the cochlea ,and decreased number of spiral ganglion cells .The ultrastructure changes of outer hair cells and spiral ganglion cells included the break -ups ,disappearance or vacuolar change of mitochondria cristas .Conclusion Our data demonstrate that chronic man-ganism can cause loss of outer hair cells and spiral ganglion cells in cochlear in rats ,leading to hearing loss .

Effect of micro-ecological environment on incidence of allergic rhinitis on mice / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#This study was designed to find out the impact of micro-ecological environment on the incidence of allergic rhinitis after developing a model of allergic rhinitis on mice.@*METHOD@#Sixty mice were randomly divided into GF group (n=30) and SPF group (n=30). Mice of GF group were fed in the germ-free environment and mice of SPF group were fed in the specific pathogen-free environment. Then each group were randomly divided into model group (20 mice) and control group (10 mice). Establish allergic rhinitis model in the mice of model group using ovalbumin (OVA) at the age of 6 weeks, observe and score the corresponding symptoms and signs that could been induced. Stain with hematoxylin eosin (HE) staining method for nasal mucosa to observe the morphological changes. Using enzyme linked immunosorbent assay to detect the concentration of IgE, IFN-γ and IL-4 in the peripheral blood serum.@*RESULT@#The chi square test showed that the incidence of allergic rhinithis in the mice of GF group was significantly higher than that in the SPF group (P< 0. 05). HE staining showed that the nasal mucosas of allergic rhinitis positive reaction mice were highly congestive and edematous and had a large number of inflammatory cell infiltration, while there was no abnormal morphology of nasal mucosas in mice with no allergic rhinitis reaction. EOS counting displayed that the number of eosinophilic cells in nasal mucosa of positive allergic rhinitis reaction mice was increased significantly. The concentration of IgE and IL-4 in the serum of positive allergic rhinitis reaction mice was highly increased (P <0. 05), and IFN-γ was significantly decreased (P< 0.05).@*CONCLUSION@#The difference of micro-ecological environment may play a key role in the occurrence of allergic rhinitis in mice.

Acute Deafness Induced by Co -administration of Kanamycin Sulfate and Furosemide in a Rat Animal Model / 听力学及言语疾病杂志

Objective To evaluate the effect of co -administration of the loop diuretic furosemide (Fur) and kanamycin (KM ) in the rats in order to establish a reliable animal model of sensorineural hearing loss .Methods Thirty -two Sprague-dawley (SD) rats were randomly divided into 4 groups with 8 rats in each group .Rats in group A ,B and C received a single intraperitoneal injection of kanamycin sulfate (KM ,500 mg/kg) ,followed by an-other intraperitoneal injection of furosemide (Fur ,0 .2 ml/kg ) 30 minutes later .While ,rats in control group D re-ceived same doses of normal saline .Auditory brain responses (ABRs) were recorded at 1 ,7 and 14 day after the in-jections ,which were group A ,group B and group C ,respectively .Hair cell loss ,the spiral ganglions and microstruc-ture were observed by immunofluorescence and scanning electron microscopy .Results The ABR thresholds in group A ,B and C were significantly higher than that of in control group D (P0 .05) .Immunofluorescence and scanning electron microscopy showed obvi-ous hair cell loss in the basal turn in each kanamycin groups ,with cilia disarrangement and fusion ,compared to the same areas in animals from the control group .The expression of cleaved caspase -3 significantly increased in each experimental group than that of in the control group(P<0 .05) .Conclusion Co -administration of furosemide and kanamycin intraperitoneally induces profound hearing loss in rats and is an effective method of establishing acute hearing loss model in animal experiments .

Analysis of clinical data of 43 cases of parapharyngeal space tumors / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To learn the anatomical structure of the parapharyngeal space and to analyze the pathological type, preoperative evaluation and choice of surgical approach of parapharyngeal space tumors.@*METHOD@#To conduct a retrospective analysis of the clinical data of 43 patients who receive surgery in our department from March 2002 to January 2011. All patients undergo enhanced CT and MRI before surgery and enhanced CT reconstruction was also adopted in the cases after the year 2009. All 43 cases of surgeries were performed under general anesthesia. Of all the cases, the lateral neck path were chosen for 38 cases, lateral neck parotid path for 3 and lateral neck path combined with mandibular split operation for 2, 1 of which tracheotomy was conducted. Suction drainage was placed in the surgical cavity of all cases. And patients without contraindications were treated with glucocorticoids.@*RESULT@#In 42 of all 43 cases, the tumor was removed completely during the first operation while tumor reoccurred after 3 years and was cured by reoperation in the other one case.@*CONCLUSION@#Parapharyngeal space is deep and the anatomy structure is complicated. Cancer incidence rate is low and mostly benign in this regional. Surgical resection is the preferred treatment and lateral neck approach is most commonly used. CT and MRI is an effective preoperative examination and enhanced CT reconstruction can provide a more intuitive spatial conformation.

Construction of prnp gene knockout vector and its transfection in eukaryotic cell / 生物工程学报

It is one of the frequently utilized strategies for positive-negative selection to elevate the gene targeting efficiency in somatic cells by enriching targeted colonies. Knocking out prnp in animals by gene targeting can prevent it from expressing Prion protein (Pathogenic protein of transmissible spongiform encephalopathy), which enables it to resist infection of Prion. We constructed a bovine prnp biallelic targeting vector via the positive-negative selection strategy, and transfected the linearized vector into the bovine fetal fibroblasts through electroporation. Then, we selected cells in cell culture medium with G418 under a concentration of 600 microg/mL followed by Ganciclovir (GCV) under a concentration of 200 nmol/mL. In the end, we successfully obtained 176 cell clones. All these clones were identified by means of sequencing, immunofluorescence and western blotting, respectively, confirming that there existed 9 positive cell clones. The results showed that the bovine prnp gene was successfully knocked out. Conclusively, we provide an effective way to knockout bovine prnp gene, which could serve as the basis for producing prion protein gene knockout transgenic cloned cattle.

Site-directed mutagenesis of MSTN gene by gene targeting in Qinchuan cattle / 生物工程学报

Myostatin, a member of the transforming growth factor beta (TGF-beta) family, is a negative regulator for muscle growth. Loss of the function of this gene is associated with the phenotype described as "double muscling", an extreme form of muscle development characterized by a large increase in muscle mass. Two replacement vectors, pA2T-Mstn4.0 and pA2T-Mstn3.2, were constructed, linearized, and transfected into the bovine fetal fibroblasts through electroporation. 170 drug-resistant cell colonies were obtained in cell culture medium containing 600 microg/mL G418 and 50 nmol/L GCV. Targeted homologous integration occurred in colony No. 58 as identified by PCR, and the targeted colony was further confirmed by sequencing and Southern blotting. This suggested that one allele of myostatin was successfully mutagenized in bovine fetal fibroblasts.

Product safety analysis of somatic cell cloned bovine / 生物工程学报

Somatic cell cloning (nuclear transfer) is a technique through which the nucleus (DNA) of a somatic cell is transferred into an enucleated oocyte for the generation of a new individual, genetically identical to the somatic cell donor. It could be applied for the enhancement of reproduction rate and the improvement of food products involving quality, yield and nutrition. In recent years, the United States, Japan and Europe as well as other countries announced that meat and milk products made from cloned cattle are safe for human consumption. Yet, cloned animals are faced with a wide range of health problems, with a high death rate and a high incidence of disease. The precise causal mechanisms for the low efficiency of cloning remain unclear. Is it safe that any products from cloned animals were allowed into the food supply? This review focuses on the security of meat, milk and products from cloned cattle based on the available data.

Protective effect of oyster extract on apoptosis of cerebral neural stem cells induced by hyperthermia / 中国组织工程研究

BACKGROUND: Previous results of our study show that oyster extract has some protective effects on apoptosis of the neuroepithelium in neural tube defects induced by hyperthermia in vivo.It remains unclear whether the extraet also protects in vitro cultured neural stem cells.OBJECTIVE: To investigate the protective effect of oyster extract on apoptosis of cerebral neural stem cells induced by hyperthermia.METHODS: The cerebral neural stem cells of embryonic mice of 13 days were cultured in vitro.Nestin expression was detected by immunofluorescence method to identify neural stem cells.The neural stem cells of passage 3 were divided randomly into 4groups: hyperthermia control group and oyster treated Ⅰ,Ⅱ,Ⅲ groups(mass concentration 2.5,5,10 g/L oyster extract solution).In addition,culture solution control group(no cells),and culture solution+oyster extract control group(no cells)were designed.All oyster extract groups and control groups were treated by hyperthermia over 39 ℃.The survival rate and the vitality of neural stem cells were detected by trypan blue staining and MTT assay.Western-blotting was employed to explore the expression of p53 in cerebral neural stem cells of each group.RESULTS AND CONCLUSION: The survival rate and the value of MTT assay in oyster treated groups Ⅱ and Ⅲ were significantly greater than hyperthermia control group(P < 0.05),but the expression of p53 in oyster treated groups Ⅱ and Ⅲ were weaker than hyperthermia control group.Oyster extract plays an important protective role in the apoptosis of neural stem cells induced by hyperthermia.