Xanthan gum is a microbial, natural high molecular weight polysaccharide produced by a the bacterium Xanthomonas campestris. Due to its exceptional rheological properties, its numerous areas of application cover a broad range. This review focuses on various aspects of xanthan production, properties, degradation, and application.

Objective To investigate the status of the disease of the fluorosis and arsenism caused by coal-burning in Ankang city of Shaanxi. Methods Nine survey spots were chosen to carry out the epidemiological investigation of adult skeletal fluorosis and arsenism in the coal-polluted areas of Ankang, respectively using Determination of Fluorine in Coal (GB/T 4633-1997) to determine the coal fluorine and using hydride generation atomic fluorescence spectrophotometry(HCAFS) to determine coal arsenic. The diagnose of the adult skeletal fluorosis followed the Diagnosis of Clinical Classification for Endemic Skeletal Fluorosis Standard(GB 16396-1996), that of arsenism using Standard of Diagnosis for Endemic Arsensim (WS/T 211-2001). Results Totally 569 adults were investigated over the age of 16, among which 121 cases were skeletal fluorosis, with a total detection rate of 21.27%. Four cases of II degree and higher skeletal fluorosis patients were identified, accounting for 0.70% of the number of subjects. One hundred and thirty-two cases of arsenic poisonin were detected, in a rate of 23.20%. Ninety-five patients were identified with moderate or severe arsenic poisoning, accounting for 16.69% of subjects. A positive correlation was found between the detection rates of the skeletal fluorosis and the arsenism(r = 0.816, P < 0.01), as well as between the detection rate of skeletal fluorosis and fluoride content of coal(r = 0.775, P < 0.05). The detection rate of arsenism and arsenic content of coal also had close relationship (r = 0.761, P < 0.05). The detection rate of skeletal fluorosis in the group aged 40 - ,50 - , and 60 - [27.20%(34/125) ,29.27%(36/123), 28.13%(36/128)] was increased, compared the group of less than 40 years age[7.77%( 15/193), X~2 = 21.969,25.648,23.856,P<0.01].For the detection rate of arsenism,male[33.67%(99/294)]was obviously higher than female[12.00%(33/275),)(X~2=37.162,P<0.01].Conclusions A high detection rate of fhorosis is correlated with arsenic poisoning,but the probability of the two diseases simultaneously occurred in a person is not high.In this polluted area.when fluoride accumulates to a certain level as in aduh,the detection rates no longer varies obviously;however,that of arsenism increases along with the age.

Objective To investigate the expression of steroidogenic factor 1 ( SF-1 ) in eutopic endometrium,ovarian endometriosis (EM) and adenomyosis.Methods From Jan.2008 to Dec.2010,30 patients with both ovarian endometriotic cysts and adenomyosis underwent hysterectomy,cystectomy or adenxectomy in Peking University First Hospital.The combination of ovarian EM and denomyosis were confirmed in 17 cases.In the mean time,endometria form 10 patients with cervical intraepithelial neoplasm ( CIN ) Ⅲ underwent hysterectomy were selected as controls.The expression of SF-l in eutopic endometrium,ovarian EM and adenomyosis was detected by immunohistochemistry staining.Results No immunoreactivity of SF-l was observed glandular cell and stromal cell in eutopic endometrium of both groups.14/17 of positive rate of SF-l were observed in lesions of ovarian endometriosis.SF-l protein was not expressed in the endometrial glandular cells of ovarian EM and in adenomyosis foci.Conclusion The differences of SF-l expression in ovarian endometrioma and adenomyosis foci might mediate the development of the disease.

With dwindling number of new antibiotics and inappropriate use of antibiotics, the emergence and spread of antibiotics resistance occurs commonly in healthcare institutions worldwide. In China, antibiotics are commonly overprescribed and misused. This study is to assess the effect of the nationwide special campaign on antibiotic stewardship program (ASP) at specialized hospitals in China by investigating prescription information from 2011 to 2012. Data on the hospital consumption and prescription of systemic antibiotics were obtained from four specialized hospitals, including maternity, children's, stomatological and cancer hospitals. Systematic random sampling was used to select outpatient prescriptions and inpatient cases. A total of 105 specialized hospitals in 2011 and 121 specialized hospitals in 2012 were analysed. The defined daily doses (DDDs) per 100 inpatient days, the percentage of antibiotic use in outpatient prescriptions, and the percentage of antibiotic use in inpatient cases were used as measurements of antibiotic use. The overall antibiotic use density in the selected hospitals decreased between 2011 and 2012 from 39.37 to 26.54 DDD/100 inpatient days (P<0.001). The percentage of antibiotic use in outpatient prescriptions (range: 24.12%-18.71%, P=0.109) and inpatient cases (64.85%-60.10%, P=0.006) also decreased within the two years. Significant changes were observed among regions and different hospitals within the two years. And antibiotic consumption was correlated with the type and size of specialized hospital in 2012, but not with the regions. This analysis of antibiotic consumption of specialized hospitals allows relevant comparisons for benchmarking and shows that national ASP has improved antibiotic rational use in China. The data will assist policymakers in formulating effective strategies to decrease antibiotic overuse and identify areas that require further work.

Animals ; Animals, Newborn ; Cerebral Cortex ; drug effects ; metabolism ; Hypoxia-Inducible Factor 1, alpha Subunit ; metabolism ; Hypoxia-Ischemia, Brain ; metabolism ; Progesterone ; pharmacology ; Rats ; Rats, Sprague-Dawley

Objective To study the determination method of total flavonoids in Gansu Astragali Radix and Hedysarum Polybotrys. Methods Calycosin glycosides etc. was selected as reference substances, comparison on the difference of absorption curves was done by ultraviolet spectroscopy and colorimetric method (NaNO2-Al(NO3)3-NaOH, AlCl3, Mg(Ac)2, NaOH, phosphomolybdic acid, HCl-Mg power). Results With colorimetric method, the maximum absorption wavelength of referrence and the test was inconsistent. The absorption peak shape was also different. With UV method, Calycosin glycosides in band Ⅱ (260 nm) showed a shoulder absorption. Astragali Radix and Hedysarum Polybotrys also showed characteristic shoulder absorptions in band Ⅱ with absorption wavelength at 263 nm and 265 nm. So the sample absorption wavelength is basically the same as that of the control sample. Conclusion Colorimetries usually used for determination of total flavonoids are not suitable for the comparison determination of Gansu Astragali Radix and Hedysarum Polybotrys. It is suitable for determining the contents of total flavonoids in samples by UV spectrophotometry at the band Ⅱ, which is the characteristic absorption band of isoflavone compound.

Objective To evaluate the relationship between genetic polymorphism of transforming growth factor (TGF)-β1 and susceptibility of liver cirrhosis after hepatitis B virus infection in Chinese population. Methods CBM, VIP, CNKI, Wanfang technological periodical full-text databases and Pubmed from set up to July, 2013 were electronically searched to identify case-control studies on the relationship between genetic polymorphism of TGF-β1 promoter 509 site, co-don 869 site and liver cirrhosis after hepatitis B virus infection. The data were quantitatively analyzed by RevMan 5.1 soft-ware after assessing the quality of included studies. Results Six case-control studies were selected for Meta-analysis based on our inclusion and exclusion standards. The results of Meta-analysis showed that the pooled OR value for liver cir-rhosis among Chinese patients after hepatitis B virus infection with T allele of TGF-β1 gene at promoter 509 was 1.02 (95%CI:0.67-1.54), the pooled OR values for patients with TT and CT genotypes were 0.80 (95%CI:0.36-1.78). OR values for pa-tients with C allele of TGF-β1 gene at codon 869 was 1.05 (95%CI:0.69-1.62), the pooled OR values for patients with CC and CT genotypes were 0.98 (95%CI:0.48-2.00). No significant publication bias was found. Conclusion The genetic poly-morphism of TGF-β1 at promoter 509 and codon 869 showed no association with susceptibility of liver cirrhosis after hepati-tis B virus infection in Chinese population.

ObjectiveTo investigate the current situation of coal-burning borne endemic fluorosis in the infected area,the usage of defluoridation stove and the formation of related behavior; to evaluate the control effect,so as to provide a theoretical basis for superiors' policy-making.MethodsNine villages in three counties of Ankang city and Hanzhong city Shanxi province were monitored in 2010.Choose five disease infected villages with oven changed in the three monitoring counties,and 10 families were randomly selected in each of the nine monitoring points and every chosen village,and a survey on the stove using and related behavior changes was carried out.By using Dean method,the dental fluorosis of every child aged 8 - 12 in the monitoring villages was examined.Meanwhile 10 copies of urine samples were randomly collected in each age group in the above-mentioned villages.The content of fluoride in urine was determined by F-ion selective electrode(WS/T 30-1996) and evaluated according to “The Normal Concentration of Urinary Fluoride of Population” (WS/T 256-2005).Twenty men over 25years old in the monitoring counties were randomly selected in each age group to be examined skeletal fluorosis by X-rays,and diagnosis was based on “The Endemic Skeletal Fluorosis Standard”(WS 192-2007).ResultsThe proper utilization rate and the qualified households of iron stoves and improved stoves,the correct drying rate and the correct storage rate of peppers and coms were all low.The washing rate of corns and peppers before eating was higher than 95％.Of the 350 children being examined of dental fluorosis in the 9 monitoring villages,the detection rate of dental fluorosis was 59.71％ (209/350).A total of 871 adults over the age of 25 were examined,and the detection rate of skeletal fluorosis was 17.22％ (150/871).A total of 350 copies of children urine samples were tested and the fluoride content were between 0.07 - 2.02 mg/L,the geometric mean value of fluoride content was 0.66 mg/L.ConclusionsThe coal-burning borne endemic fluorosis in Shanxi is in a growth phase,many defluoridation stoves are out of order,and the formation of healthy behaviors is low.To strengthen the disease surveillance,health education and management of defluoridation stoves are keys to prevent coal-burning borne endemic fluorosis in the future.

Objective To investigate the running conditions of the water improvement projects and the role of these projects in reducing fluoride in drinking-water type of fluorosis in Shaanxi province, and provide a scientific basis for prevention and control of the disease. Methods Forty-eight villages of 16 counties in Xi'an, Baoji, and Yulin cities of Shaanxi province were monitored in 2009. Five water samples were collected randomly in water unimproved monitoring villages by the position of east, west, south, north, and center parts. In water improved monitoring villages, 3 tap water and one source water samples were collected. Water fluoride was tested using fluoride ion selective electrode method according to the "Standard Testing Methods for Drinking Water" (GB/T 5750-2006). All school children aged 8 to 12 in monitored villages were examined their dental fluorosis using Dean criteria. All people over 16 years old were examined clinical skeletal fluorosis, and 30% of the project counties were randomly selected, then randomly selected one village among these counties, clinically diagnosed patients with skeletal fluorosis were examined again by X-ray using "Diagnostic Criteria of Endemic Skeletal Fluorosis"(WS 192-2007). Urine samples of 30 children aged 8 to 12 and of 20 adults over the age of 16 were randomly collected, urinary fluoride was tested according to "the Determination of Urinary Fluoride by Ion Selective Electrode Method" (WS/T 89-19%). Results Of the 22 water improvement projects that in normal operation, fluoride level of 8 source waters exceeded the standard, accounting for 36.36%(8/22), and projects scrapped 5. Two hundred and two water samples were tested. In water improved historical diseased areas, the median of water fluoride of source water and tap water were 0.72,0.62 mg/L, respectively, and the average rate of water fluoride exceeded the standard ere 36.36%(8/22) and 31.94%(23/72), respectively. In water unimproved historical diseased areas, the median of water fluoride was 1.00 mg/L, and the average rate of water fluoride exceeded the standard was 39.81%(43/108). Detection rate of dental fluorosis among children aged 8 to 12 was 16.06% (367/2285), dental fluorosis index was 0.30, and the prevalence was negative. Detection rate of clinical skeletal fluorosis among adults over 16 years old was 5.09%(1542/30 272), a totally of 198 people had X-ray film taken, positive 68, the positive detection rate was 34.34%(68/198). One thousand and fifty-one copies of children's urine samples were tested, geometric mean of urinary fluoride was 0.95 mg/L; nine hundred and fourteen copies of adults urine samples were tested, geometric mean of urinary fluoride was 1.16 mg/L Conclusions Drinking-water type of fluorosis affects a large area in Shaanxi province, the disease is still serious, and the task of prevention remains very arduous. Further intensify the water improvement project in diseased areas, and strengthen disease monitoring, health education and water improvement project management is the key to prevention and control of endemic fluorosis.

Abstract: Objective　To analyze the serotype distribution, drug resistance rate and drug resistance gene carrying of Streptococcus pneumoniae isolates in hospitalized patients, and evaluate the coverage of the vaccine to the serotype of Streptococcus pneumoniae in this area, so as to provide reference for the rational use of antibiotics in clinic. Methods　A total of 150 strains of non-repetitive Streptococcus pneumoniae isolated from inpatients from January 2015 to December 2019 were collected for serotyping and antimicrobial sensitivity test. The carrying rates of pbp2b, ermB and tetM were detected by PCR. Results　The PCR classification rate of 150 strains of Streptococcus pneumoniae was 93.1%, and the classification rate of capsular swelling test was 100%, and a total of 19 serotypes were divided, mainly 19F and 6B. Children's serotypes were predominantly 19F, 6B, and 15A; adult serotypes were predominantly 19F, 14, and 23F. The coverage rates of the PCV7, PCV10, PCV13 and PPV23 vaccines were 36.8%, 42.1%, 57.9% and 68.4%, respectively. Strains with serotypes of 19F, 6B, 3, and 23F had higher rates of resistance to antimicrobials. The sensitivity of Streptococcus pneumoniae to penicillin was greater than 96.0%. Antimicrobials with significant differences in resistance rates between invasive and non-invasive strains were penicillin, moxifloxacin, and levofloxacin. The percentage of strains carrying both ermB and tetM resistance genes was 96.0%, and the concordance rate between pbp2b, ermB and tetM resistance genes and the resistance phenotype was >98.0%. A total of 10 multi-resistance combinations were detected, with a multi-resistance rate of 62.6%, and the multi-drug resistance pattern of Streptococcus pneumoniae was mainly concentrated in the 19F and 6B serotypes. Conclusion　There are significant age differences in the serotypes of Streptococcus pneumoniae in this area. The vaccine currently used has low coverage in this region and therefore offer limited protection to the population. The drug resistance rates of Streptococcus pneumoniae varied significantly among serotypes. Erythromycin and tetracycline are not recommended for clinical treatment of Streptococcus pneumoniae. Penicillin can still be used as the first choice for clinical treatment of Streptococcus pneumoniae infection.