Genetic deletion or pharmacological inhibition of soluble epoxide hydrolase attenuated particulate matter 2.5 exposure mediated lung injury.

Air pollution represented by particulate matter 2.5 (PM2.5) is closely related to diseases of the respiratory system. Although the understanding of its mechanism is limited, pulmonary inflammation is closely correlated with PM2.5-mediated lung injury. Soluble epoxide hydrolase (sEH) and epoxy fatty acids play a vital role in the inflammation. Herein, we attempted to use the metabolomics of oxidized lipids for analyzing the relationship of oxylipins with lung injury in a PM2.5-mediated mouse model, and found that the cytochrome P450 oxidases/sEH mediated metabolic pathway was involved in lung injury. Furthermore, the sEH overexpression was revealed in lung injury mice. Interestingly, sEH genetic deletion or the selective sEH inhibitor TPPU increased levels of epoxyeicosatrienoic acids (EETs) in lung injury mice, and inactivated pulmonary macrophages based on the MAPK/NF-κB pathway, resulting in protection against PM2.5-mediated lung injury. Additionally, a natural sEH inhibitor luteolin from Inula japonica displayed a pulmonary protective effect towards lung injury mediated by PM2.5 as well. Our results are consistent with the sEH message and protein being both a marker and mechanism for PM2.5-induced inflammation, which suggest its potential as a pharmaceutical target for treating diseases of the respiratory system.

Prevalence and associated factors of HIV self-testing among men who have sex with men in Ningbo, China: a cross-sectional study.

BACKGROUND: HIV testing and early linkage to care are critical for reducing the risk of HIV transmission. HIV self-testing (HIVST) is a useful tool for increasing HIV testing frequency.This study aimed to investigate HIVST rates among men who have sex with men (MSM), the characteristics of MSM who had HIVST, and factors associated with HIVST uptake among MSM in Ningbo, China. METHODS: A cross-sectional study was conducted from April to October 2019 in Ningbo,China. Participants were aged at least 18 years and having had sexual contact with men in the past year. Proportions were used for categorical variables. Adjusted Odds Ratio (AOR) and 95% Confidence Interval (CI) for characteristics associated with HIVST uptake was processed by multivariable logistic regression models. RESULTS: Among a sample of 699 MSM recruited, 38.2% had reported previous use of an HIV self-test kit. A greater proportion of HIVST users had a higher frequency of HIV testing (≥ 2 times: 70.0% versus 41.2%, p < 0.001) in the past 1 year. The odds of older age (30-39 years: AOR = 0.49, CI 0.32-0.76; more than 40 years: AOR = 0.07, CI 0.04-0.14, compared to 18-29 years), bisexual (AOR = 0.49, CI 0.29-0.84) were lower among HIVST users,and were higher among MSM who were higher education level (high school: AOR = 2.82, CI 1.70-4.69, compared to middle school or less), gay apps use (AOR = 1.86, CI 1.13-3.05), multiple male sex partners (AOR = 1.90, CI 1.29-2.80), frequency of male-male sexual contact ≥ 1 times per week (AOR = 1.86, CI 1.30-2.66), syphilis infection (AOR = 5.48, CI 2.53-11.88). CONCLUSIONS: Further HIVST education should be strengthened for school-aged children and teenagers, and free HIVST kits may be provided to high-risk MSM through gay apps and CBO to achieve the increased HIV testing frequency.

[Effects of slope position and aspect on structure and species diversity of shrub community in the Jiajin Mountains, Sichuan Province, China]. / å¡å‘å’Œå¡ä½å¯¹å››å·å¤¹é‡‘å±±çŒä¸›ç¾¤è½ç»“æž„ä¸Žç‰©ç§å¤šæ ·æ€§ç‰¹å¾çš„å½±å“.

We examined the impacts of slope direction and position on the community structure and species diversity of shrub community in Jiajin Mountains. The results showed that a total of 186 vascular plant species belonging to 50 families and 127 genera were recorded in the 24 sample plots. 32 species belonging to 14 families, 22 genera were recorded in the shrubs layer, with most species distributed at lower position of the shady slope. 154 species belonging to 43 families and 109 genera were recorded in the herbaceous layer, with the species number being the lowest on the shady slope. The average height of the shrub layer showed a decreasing order of sunny slope, semi-sunny slope, and shady slope, while an opposite order was observed for the average density. The average height of the herb layer was in the decreasing order of the shady slope, semi-sunny slope, sunny slope, whereas no significant changes were observed for the average density. The slope position had significant effect only on the average height of the herbaceous layer on the sunny slope. The overall level of species diversity in the shrub layer on the shady slope was relatively high, while that in the herbaceous layer was relatively high at the lower position of the sunny slope and at the middle position of the shady slope. Slope aspect had significant effect on species richness index, Shannon diversity index, Simpson dominance index, Pielou evenness index of shrub and herb layers except for Simpson index of herb layer. Slope position did not affect these indices. The interaction effect of slope aspect and position on the diversity index for herb layer was greater than that for the shrub layer. Results from redundancy analysis showed that species diversity was related to sin(aspect), cos(aspect), and community structure.

Maternal energy insufficiency affects testicular development of the offspring in a swine model.

We determined the effects of insufficient maternal energy on testicular development in offspring in a swine model. Thirty-six sows were divided into control (CON) and low-energy diet (LE) groups during gestation. We observed that the number of Sertoli, germ, and Leydig cells in the offspring of the CON group were significantly higher than those in the LE group at 28 and 120 d after birth. Furthermore, the percentage of apoptotic testis cells was significantly higher in the offspring of the LE group than in the CON group. Transcriptome analysis of differentially expressed mRNAs and long noncoding RNAs in offspring testes indicated that these RNAs were mainly involved in lipid metabolism, apoptosis, cell proliferation, and some pivotal regulatory pathways. Results revealed that AMPK-PI3K-mTOR, MAPK, and oxidative phosphorylation signaling pathways play an important role in mediating the programming effect of insufficient maternal energy on testicular development, and that this effect occurs mainly at an early stage in life. mRNA and protein expression analyses confirmed the importance of certain signaling pathways in the regulation of testicular development. This study provides insights into the influence and possible mechanism underlying the effect of inadequate maternal energy intake on testicular development in the offspring.

Effect of intra-uterine growth restriction on long-term fertility in boars.

The present study assessed the effect of birthweight on reproductive performance, including a possible mechanism, in male pigs. Ten newborn male piglets, including five normal birthweight (NBW) piglets and five intra-uterine growth restricted (IUGR) piglets, were used in the study. All piglets were weaned on Day 28 and fed the same diet during the experiment (10 months). Average daily weight gain, feed intake and the feed conversion ratio were higher in NBW than IUGR piglets. Similarly, testis volume and the number of Leydig and Sertoli cells in the distal portion of the testes were higher in NBW than IUGR piglets (P<0.05). Semen volume (P<0.05) and the total number of spermatozoa per ejaculate (P=0.08) were lower in IUGR boars. Testosterone concentrations on Day 141 and prostaglandin E2 concentrations on Days 82 and 141 were higher in IUGR than NBW boars (P<0.05). The malondialdehyde content of seminal plasma was higher in IUGR boars, whereas sperm glutathione peroxidase activity was lower in IUGR versus NBW boars (P<0.05). Expression of DNA methyltransferase (Dnmt) genes Dnmt1, Dnmt3a, histone-lysine N-methyltransferase (Suv39h2), and lysine (K)-specific demethylase Kdm4a was upregulated in testes from IUGR boars. These findings suggest that growth restriction affects sperm production via reproductive organ development and epigenetic regulation.

Coxsackievirus A16 induced neurological disorders in young gerbils which could serve as a new animal model for vaccine evaluation.

Coxsackievirus A16 (CA16) is one of the major pathogens associated with human hand, foot, and mouth disease (HFMD) in the Asia-pacific region. Although CA16 infections are generally mild, severe neurological manifestations or even death has been reported. Studies on CA16 pathogenesis and vaccine development are severely hampered because the small animal models that are currently available show major limitations. In this study, gerbils (Meriones unguiculatus) were investigated for their suitability as an animal model to study CA16 pathogenesis and vaccine development. Our results showed that gerbils up to the age of 21 days were fully susceptible to CA16 and all died within five days post-infection. CA16 showed a tropism towards the skeletal muscle, spinal cord and brainstem of gerbils, and severe lesions, including necrosis, were observed. In addition, an inactivated CA16 whole-virus vaccine administrated to gerbils was able to provide full protection to the gerbils against lethal doses of CA16 strains. These results demonstrate that gerbils are a suitable animal model to study CA16 infection and vaccine development.

Effect of dietary supplementation with amino acids on boar sperm quality and fertility.

The aim of this study was to evaluate the effects of dietary supplementation with amino acids on sperm quality and fertility rates after insemination with boar semen. Twelve Yorkshire boars were paired by age and allocated to one of two dietary treatments composed of total lysine levels of 0.64% (T1) and 0.96% (T2), with the lysine: methionine: threonine: tryptophan: valine ratio in the diets set to 100:27:73:19:69 through the addition of synthetic amino acids. Semen was collected twice weekly (phase 1, 1-12 wk); every other day (phase 2, 13-16 wk); twice weekly (phase 3, 17-26 wk); and daily (phase 4, 27-28 wk). Semen was collected from boars during phase 3 and used to inseminate 64 multiparous sows. Our results showed that sperm concentration and total sperm cells were greater in boars in T2 than in boars in T1 in phases 2 and 4 (P<0.05). Sperm motility parameters, morphologically normal sperm, and acrosome integrity in T2 boars were greater than those in T1 boars (P<0.05) during the experiment. Free amino acid concentrations in seminal plasma increased in T2 boars (P<0.05). Furthermore, sows inseminated with semen collected from T2 boars gave birth to more live piglets than those inseminated with semen collected from T1 boars (P=0.04). In conclusion, supplementation of boar diet with amino acids improves sperm quality, and subsequently increases fertilization capacity and the number of live piglets.

Effect of different amino acid patterns on semen quality of boars fed with low-protein diets.

The objective of the present study was to determine the effect of different amino acid patterns on the semen quality of boars fed with low-protein diets. Twenty-four boars were randomly divided into 4 groups (HP, LP1, LP2, and LP3). HP boars received 17% crude protein diet with a lysine:threonine:tryptophan:arginine (Lys:Thr:Trp:Arg) ratio of 100:50:20:104. Other boars received 13% CP and similar Lys levels (0.84%) with Lys:Thr:Trp:Arg ratios of 100:50:20:71, 100:76:38:71, and 100:76:38:120 for LP1, LP2, and LP3, respectively. These results showed sperm motility in the LP3 group was higher than in HP group during the 13-22 week period. The total sperm number, acrosome integrity ratio, and the effective total sperm number in LP3 and LP2 was higher than in other groups, and the abnormality ratio was lower than in other groups during the 13-18 week period. During 19-22 week period, in LP1 and LP3 groups, total sperm number and effective total sperm number were higher than in other groups, abnormality ratio was lower, and acrosome integrity ratio was higher than in the HP group. Nitric oxide synthase activity of seminal plasma and nitric oxide concentration of spermatozoa were significantly higher in the LP3 group than in other groups. Furthermore, mRNA expression of androgen receptor in testes was up-regulated in LP3. In conclusion, we suggest that the optimum ratio of Lys:Thr:Trp:Arg in a 13% CP diet for boars is 100:76:38:120, which results in similar or better reproductive performances than a 17% CP diet.

[Epidemiological and etiological characteristics of hand-foot-mouth disease in Ningbo, Zhejiang province, 2008-2011].

OBJECTIVE: To analyze the epidemiological characteristics of hand foot and mouth disease (HFMD) in Ningbo. METHODS: A descriptive analysis was conducted through the surveillance data of HFMD in Ningbo, Zhejiang province, from 2008 to 2011. Genes on EV71 and Cox A16 were amplified with RT-PCT from the stool samples of HFMD patients. Sequences were analyzed by bioinformatics software. RESULTS: 37 524 cases of HFMD were reported from 2008 to 2011, including 196 severe cases and 12 deaths. The reported incidence was 145.26 per 100 000 and the case fatality was 0.03%. Cases in children aged 5 or younger accounted for 95.89%, and the scattered cases accounted for 64.10%. Xiangshan and Ninghai counties had the highest incidence rates in Ningbo. The peak of incidence was from April to July. The number of male patients was obviously higher than females. 2394 cases of HFMD were laboratory confirmed and EV71 with the predominant epidemic strain. Data from phylogenetic analysis revealed that EV71 isolated from HFMD patients in Ningbo belonged to C4a evolution branch of C4 sub-genotype, with several transmission chains. Cox A16 belonged to B1 evolution branch. 53.48% of the healthy children in Ningbo showed EV71 antibody positive. The geometric mean of the antibody titer (GMT) was 11.23 (8.33 - 14.98) in healthy children. Cox A16 antibody was detected at 63.18% of the healthy children in Ningbo. GMT in healthy children was 12.61 (6.70 - 16.52). CONCLUSION: HFMD was highly endemic in Ningbo, with children under 5 years old were at high-risk. The major etiologic agent was EV71 which belonged to C4a in the C4 sub-genotypes. Cox A16 belonged to the B1 evolution branch, which were in line with the predominant virus circulating in the mainland of China.

[Study on characteristic of current measles wild-type strains after continuous passage from Vero cells].

OBJECTIVE: To investigate the change on infection capacity of measles epidemic strain after continuous passage from Vero cell line, and to analyze the possible reasons in genetic level that caused change on cell-recognition site. METHODS: Measles virus epidemic strain Ningbo 05-2 was continuous passaged from Vero cells and Cytopathic Effect (CPE) was observed and recorded. After confirmation by real-time Reverse Transcription-Polymerase Chain Reaction (RT-PCR), hemagglutinating activity of Ningbo 05-2/P18 was detected using hemagglutination (HA) test and the completed sequences within Hemagglutinin (H) and Necleoprotein (N) gene were amplified by RT-PCR. RESULTS: Measles epidemic strain Ningbo 05-2 has been continuous cultured for 17 times (P18) on Vero cells, but CPE began to be observed from the 13th passage. Although the passaged strains were confirmed as measles virus by real-time RT-PCR, the hemagglutinating activity of Ningbo 05-2/P18 was still negative. Compared with the Ningbo 05-2, there were three amino acid mutations within H protein of Ningbo 05-2/P18 (312aa, 314aa, 546aa), which changed the beta-sheet on the 311aa and the beta-turn during 312aa to 316aa to the alpha-helix. Phylogenetic tree based on H gene indicated the Ningbo 05-2/P18 still belonged to sub-genotype H(1b), locating at the same branch with the original strain. However, sequences of the original and passaged strains were identical within N protein. CONCLUSIONS: Only a few amino acid mutations within H protein could results in cell-recognition site alternative of measles epidemic strain after continuous culture in Vero cell line, and consequently affecting the infection of measles virus.

Long-term clinical observation of the immunogenicity of inactivated hepatitis A vaccine in children.

110 children who were given the complete course of the inactivated hepatitis A vaccine (Havrix) were followed up 10 years later. Age-matched healthy children who were not inoculated served as controls. One month after two primary injections, all children were positive for serum antibody. After 10 years, 99.09% of inoculated children remained positive for serum anti-HAV antibody, with a geometric mean concentration (GMC) of 61.59mIU/mL. GMC values following a secondary immunization in children with antibody levels <20mIU/mL were significantly elevated (567.9mIU/mL), compared with the primary injection alone. Havrix appears to induce persistent immunity and potent immune memory.

HBV genotype C is independently associated with cirrhosis in community-based population.

AIM: To determine the association of hepatitis B virus (HBV) genotypes with probable cirrhosis and fatty liver in community-based populations. METHODS: A multi-stage cluster probability sampling method was applied to recruit 10 167 subjects aged between 6 and 72 years from our epidemiological bases in Eastern China. After excluding the subjects co-infected with hepatitis C or hepatitis D viruses, the hepatitis B surface antigen (HBsAg)-positive subjects were examined for HBV genotype, serum viral load, alanine aminotransferase (ALT), hepatitis B e antigen (HBeAg) status, and ultrasonographic changes. Logistic regression models were used to determine the factors associated with probable cirrhosis and fatty liver. RESULTS: Of 634 HBsAg-positive subjects with HBV genotype determined, 82 had probable cirrhosis (ultrasonographic score > or = 5), 42 had ultrasonographic fatty liver. Probable cirrhosis was only found in the HBeAg-negative subjects, and more frequently found in the subjects with genotype C than in those with genotype B (14.8% vs 8.0%, P = 0.018). In HBeAg-negative subjects, high viral load was frequently associated with abnormal ALT level, while ALT abnormality was more frequent in those with probable cirrhosis than those without (19.5% vs 7.8%, P = 0.001). Univariate analysis showed that age, sex, HBV genotypes, and viral load were not significantly associated with ultrasonographic fatty liver, whereas ALT abnormality was significantly related to ultrasonographic fatty liver (OR = 4.54, 95% CI: 2.11-9.75, P < 0.001). Multivariate analysis demonstrated that HBV genotype C, age (> or = 45 years), male sex, and ALT abnormality were independently associated with probable cirrhosis (AOR = 2.30, 95% CI: 1.26-4.19; AOR = 1.81, 95% CI: 1.10-2.99; AOR = 1.74, 95% CI: 1.03-2.95; AOR = 2.98, 95% CI: 1.48-5.99, respectively). CONCLUSION: A crude prevalence of probable cirrhosis is 12.9% in the community-based HBV-infected subjects. HBV genotype C is independently associated with probable cirrhosis in the HBeAg-negative subjects.

[Epidemiological and etiological characteristics of typhoid and paratyphoid fever in Ningbo during 1988 - 2007].

OBJECTIVE: To study the epidemiological and etiological characteristics of typhoid and paratyphoid fever in high epidemic areas. METHODS: Reported data on typhoid and paratyphoid fever during 1988-2007 in Ningbo were analyzed epidemiologically. Shellfish from the market was collected for laboratory testing and Salmonella typhi strains collected from the patients were also studied. RESULTS: Number of reported cases on both typhoid and paratyphoid fever was 19 404 with 7 deaths, from 1988 to 2007. The annual mean incidence was 17.68 per one hundred thousand with the fatality rate as 0.36 per thousand. Most cases were among adults aged 20-50 years and an obvious regional distribution was observed with high incidence seen in winter and spring. Since 1990s, the advantage strain had changed from Salmonella typhi to Salmonella paratyphi A. Etiologic studies showed that raw Anadara subcrenata and oyster were the main risk factors. One Salmonella paratyphi A strain was detected in both Anadara subcrenata and oysters collected from the market, which contained TEM-1 drug resistance gene. PFGE genotyping showed that PFGE-X2 was the strain which causing pandemic in Ningbo. CONCLUSION: Eating contaminated raw shellfish like oysters and hairy clams was the primary risk factor, responsible for the outbreaks. Salmonella paratyphi A was the advantages pandemic strain in Ningbo. Strategies as supervision on personal hygiene and health education should be strengthened.

Expression of ethylene-forming enzyme (EFE) of Pseudomonas syringae pv. glycinea in Trichoderma viride.

The efe gene encoding an ethylene-forming enzyme from Pseudomonas syringae pv. glycinea has been expressed for the first time under the control of Trichoderma reesei cbh1 promoter in Trichoderma viride. Reverse transcription polymerase chain reaction analysis showed that transformant Y2 produced mRNA of the efe gene. Southern blot analysis showed that there was one copy of efe gene which was integrated into the chromosomal DNA of T. viride. Ethylene production by transformant Y2 was efficiently induced by cellulose, while very low level of ethylene was produced when sodium carboxymethyl cellulose or lactose was used as carbon source. Peptone exerted a much greater stimulatory effect on ethylene production. A high level of ethylene was produced when transformant Y2 was cultured in solid fermentation medium containing wheat straw, indicating that plant wastes could be directly converted to ethylene by the recombinant filamentous fungus.

[Levels of transition on maternal transferred measles antibody in infants in 3 cities in China].

OBJECTIVE: To understand the epidemiological characteristics of age distribution of measles and related policies on measles vaccines (live; MV) in infants through analyzing the antibody levels of comparison in maternal-infant pairs. Transition of immunity in infants was also studied to provide theoretic basis for measles immunization strategy and to reduce the incidence of month-old infants. METHODS: In cities of Ningbo, Harbin, and Jinan from Zhejiang, Heilongjiang and Shandong provinces, data was collected from 2004 to 2007 and analyzed regarding the epidemic situation of measles. Studies on maternal-transferred measles antibody were carried our sero-epidemiologically. RESULTS: Most of the measles cases were found among babies younger than 12 months, and the incidence of < 1 year olds had been increasing. The distribution was dominated by 5 - 8 month olds in infant measles cases. The positive rate and GRMT of measles antibody in newborns were 89.3 percent and 738.93. The positive rate of the measles antibody and GMRT of the 6-month infant were 6.9% and 6.89, while 6.7% and 3.69 in 8-month infant. There was a declining trend of the positive rate of the measles antibody during the newborns to 8-month infant. The positive rate and GRMT of measles antibody in mothers were 84.3 percent and 516.94. Mother's measles antibodies mainly to be at low and moderate level, which accounted for 50.4 percent and 30.3 percent respectively, the correlation coefficient between mother and infant was 0.840. CONCLUSION: Maternal-transferred measles antibody decreased as the growth of infants. The positive rates of measles antibody were quite low in 6-month and 8-month olds which were the age range that needs most attention.

Report and analysis of a scarlet fever outbreak among adults through food-borne transmission in China.

BACKGROUND: Scarlet fever is caused by group A beta-hemolytic streptococci (GAS). The clinical syndrome has receded in recent years, but occasionally explosive outbreaks do occur likely due to the emergence of GAS with virulence factors peculiar to this syndrome. METHODS: Following the notification of an unexpectedly large number of scarlet fever cases amongst adults associated with a school in Ningbo, China, in June 2006, the epidemiological and clinical features of the outbreak were investigated. Logistic regression was conducted to investigate the risk factors of the outbreak and its transmission route. RESULTS: Forty five individuals suffered scarlet fever with an attack rate of 4.98% (45/904). There was a single peak in the epidemic curve, with the majority of the cases occurring during the first two days of the outbreak. The median age of cases was 35.5 years (range 17-65). Most patients had fever (43/45), sore throat (40/45), scarlatinoid rash (39/45) and strawberry-like tongue (30/45). In laboratory detection, 45 cases' throat swabs samples were collected and GAS were isolated from 8 throat swabs samples. All of the cases, except for 2, had eaten the Plain Boiled Chicken (PBC) for lunch on June 6th, and teaching staff and students who had not eaten the PBC were not affected by the epidemic. Logistic regression analysis indicated that PBC was a key risk factor (OR=21.0, P<0.05). The chef of the school refectory was responsible for washing, braising, cutting, and distributing the PBC, and was identified as the likely source. CONCLUSIONS: We describe an outbreak of scarlet fever caused by GAS-contaminated food.

[Analysis on the proportion of reported hepatitis B cases through pilot surveillance in China during 2006].

OBJECTIVE: To better understand the proportions of reported hepatitis B cases in pilot surveillance cites through investigation and laboratory testing. METHODS: To confirm the reported cases of hepatitis B by collecting blood specimen and laboratory testing on HBsAg, IgM of Anti-HBc, Anti-HAV in 18 pilot surveillance counties. RESULTS: Among 2858 cases of hepatitis B reported in 2006, 23.97% of them were reported as suspected acute cases, 14.87% as acute cases, 20.33% as suspected chronic cases, 34.67% as chronic cases, 4.09% as cirrhosis and 2.06% as HCC. Among 1681 reported hepatitis B cases confirmed by laboratory testing, results showed that 24.16% of them were diagnosed as acute hepatitis B, but only 15.37% were confirmed as acute hepatitis B. Although the proportion confirmed as hepatitis B kept consistent as before, misclassification was found. CONCLUSION: In current surveillance system, reported hepatitis B cases were mainly chronic, only up to one third belonged to acute hepatitis B. The reported incidence of hepatitis B did not reflect the real incidence due to misclassification. To better define the burden on hepatitis B disease, it was necessary and urgent to revise the diagnostic criteria and to conduct surveillance on hepatitis B, under separate reporting categories which including acute and chronic cases of the disease.

[Study on spectral properties of Ca2B5O9Cl : Eu prepared with hydrothermal method and solid method].

Effects of preparation methods (hydrothermal method and high temperature solid method), excitation condition, and Eu ions concentration on spectral properties of Ca2B5O9Cl : Eu phosphor were studied. The effects of preparation condition on crystal photographs were also discussed. The result showed that the Ca2B5O9Cl : Eu phosphors prepared with hydrothermal method had mainly 5 D0 --> 7F(J) (J = 1, 2, 3, 4) emission of Eu3+ with 254 nm excitation and 4 f6 5d1 --> 8S(7/2) emission of Eu2+ with 365 nm excitation, the one prepared with high temperature solid method had mainly 4 f6 5d1 --> 8S(7/2) emission of Eu2+ with 365 nm excitation and very weak emissions of Eu2+ and Eu3+ with 254 nm excitation. Eu ions concentration hardly affected spectral properties, but the preparation method and excitation conditions had remarkable influence on the properties. SEM revealed that the products prepared both in the air and reductive atmosphere had consummate crystal, slippery surface and appropriate size (0.82-1.06 microm).