Relocation of NPM Affects the Malignant Phenotypes of Hepatoma SMMC-7721 Cells.

Nucleophosmin(NPM), heavily implicated in diverse solid tumors, is an important multifunctional protein mainly located in the nucleolus. Our previous study confirmed that NPM can also localize and accumulate in the cytoplasm of liver cancer cells. However, the role of cytoplasmic NPM (NPMc +) is unclear. Here, we showed that both nucleolar NPM and NPMc+ could promote cell proliferation, although the effect of NPMc+ was weaker than that of NPM. Cell adhesion ability of hepatoma cells was significantly reduced to a greater extent by NPMc+ expression. Nucleolar NPM enhanced cell migration and invasion, whereas NPMc+ impeded cell migration and invasion. The investigation of NPM interactional proteins by proteomic method demonstrated that the NPM was involved in multiple biological processes. By contrast, the interactional proteins of NPMc+ were mainly implicated in tRNA amino acylation regulation. The interactional network of NPMc+ was significantly small and simple. These results suggested that relocation of NPM altered its interactional network and consequently disturbed the primary functions, including cell proliferation, adhesion, migration, and invasion. NPM plays a promotional role in cancer and the reducing relocation may be a potential therapeutic target for hepatocellular carcinoma. J. Cell. Biochem. 118: 3225-3236, 2017. © 2017 Wiley Periodicals, Inc.

Nucleophosmin Regulates Intracellular Oxidative Stress Homeostasis via Antioxidant PRDX6.

Reactive oxygen species (ROS) play both deleterious and beneficial roles in cancer cells. Nucleophosmin (NPM) is heavily implicated in cancers of diverse origins, being its gene over-expression in solid tumors or frequent mutations in hematological malignancies. However, the role and regulatory mechanism of NPM in oxidative stress are unclear. Here, we found that NPM regulated the expression of peroxiredoxin 6 (PRDX6), a member of thiol-specific antioxidant protein family, consequently affected the level and distribution of ROS. Our data indicated that NPM knockdown caused the increase of ROS and its relocation from cytoplasm to nucleoplasm. In contrast, overexpression or cytoplasmic localization of NPM upregulated PRDX6, and decreased ROS. In addition, NPM knockdown decreased peroxiredoxin family proteins, including PRDX1, PRDX4, and PRDX6. Co-immunoprecipitation further confirmed the interaction between PRDX6 and NPM. Moreover, NSC348884, an inhibitor specifically targeting NPM oligomerization, decreased PRDX6 and significantly upregulated ROS. These observations demonstrated that the expression and localization of NPM affected the homeostatic balance of oxidative stress in tumor cells via PRDX6 protein. The regulation axis of NPM/PRDX/ROS may provide a novel therapeutic target for cancer treatment. J. Cell. Biochem. 118: 4697-4707, 2017. © 2017 Wiley Periodicals, Inc.

Insulin resistance in ischemic stroke.

Insulin resistance often refers to a pathological condition in which cells fail to respond to the normal actions of insulin. Increasing literature has noted a critical role of insulin resistance in the pathogenesis of ischemic stroke. Insulin resistance plays an important role in the pathogenesis of ischemic stroke via enhancing advanced changes of atherosclerosis. A variety of literature indicates that insulin resistance enhances platelet adhesion, activation and aggregation which are conducive to the occurrence of ischemic stroke. Insulin resistance also induces hemodynamic disturbances and contributes to the onset of ischemic stroke. In addition, insulin resistance may augment the role of the modifiable risk factors in ischemic stroke and induce the occurrence of ischemic stroke. Preclinical and clinical studies have supported that improving insulin resistance may be an effective measure to prevent or delay ischemic stroke.

Gastroenteritis outbreaks caused by Norovirus genotype II.7 in a college in China (Zhuhai, Guangdong) in 2011.

BACKGROUND: Noroviruses are the most common cause of epidemic gastroenteritis worldwide. Noroviruses are comprised of at least five genogroups (GI-GV) and >35 genotypes. GII.7 is a nonpredominant genotype associated with Norovirus outbreaks. On November 17, 2011, Zhuhai Center for Disease Control monitored an increasing number of gastroenteritis cases at a local college. To determine the causes and control the outbreak effectively, we carried out an epidemiologic investigation. METHODS: Suspected cases were defined as those with one of the following symptoms: nausea, vomiting, abdominal pain, or diarrhea presenting on or after November 15 among the people who lived at the college. Probable cases were defined as cases with vomiting or diarrhea over three times per day on or after November 15. Confirmed cases were suspected or probable cases positive for Norovirus (nucleic acid). We conducted a case-control study to identify risk factors of the outbreak. Norovirus was tested by real-time reverse transcription-polymerase chain reaction, and Norovirus polymerase chain reaction products were further sequenced. RESULTS: In total, 63 cases were identified, which were scattered in all 14 departments of the college. The outbreak lasted for 84 h. Time distribution mode indicated a point-source outbreak. Fifty-one cases and 94 controls were contacted. Seventy-five percent of the cases compared to 19% of the controls were exposed to delicatessens (various salad and meat products) from the "Y" convenience store (odds ratio=12, 95% confidence interval 5.4-28). Laboratory tests showed 14 of the 15 cases and two asymptomatic food handlers were positive for Norovirus nucleic acid. There was 100% similarity between the cases and the food handlers when we compared the nucleotide sequences of Norovirus, which clustered with GII.7 genotype. CONCLUSIONS: Delicatessens from the "Y" convenience store were associated with the GII.7 Norovirus outbreak. We strongly recommend food supervision and quality control in convenience stores to decrease the risk of future Norovirus outbreaks.

NPM promotes hepatotoxin-induced fibrosis by inhibiting ROS-induced apoptosis of hepatic stellate cells and upregulating lncMIAT-induced TGF-ß2.

Liver fibrosis is caused by a variety of chronic liver injuries and has caused significant morbidity and mortality in the world with increasing tendency. Elucidation of the molecular mechanism of liver fibrosis is the basis for intervention of this pathological process and drug development. Nucleophosmin (NPM) is a widely expressed nucleolar phosphorylated protein, which is particularly important for cell proliferation, differentiation and survival. The biological role of NPM in liver fibrosis remains unknown. Here we show that NPM promotes liver fibrosis through multiple pathways. Our study found that NPM was up-regulated in cirrhosis tissues and activated in hepatic stellate cells (HSCs). NPM inhibition reduced liver fibrosis markers expression in HSCs and inhibited the HSCs proliferation and migration. In mice model, NPM knockdown in HSCs or application of specific NPM inhibitor can remarkably attenuate hepatic fibrosis. Mechanistic analysis showed that NPM promotes hepatic fibrosis by inhibiting HSCs apoptosis through Akt/ROS pathway and by upregulating TGF-ß2 through Akt-induced lncMIAT. LncMIAT up-regulated TGF-ß2 mRNA by competitively sponging miR-16-5p. In response to liver injury, hepatocytes, Kupffer cells and HSCs up-regulated NPM to increase TGF-ß2 secretion to activate HSCs in a paracrine or autocrine manner, leading to increased liver fibrosis. Our study demonstrated that NPM regulated hepatotoxin-induced fibrosis through Akt/ROS-induced apoptosis of HSCs and via the Akt/lncMIAT-up-regulated TGF-ß2. Inhibition of NPM or application of NPM inhibitor CIGB300 remarkably attenuated liver fibrosis. NPM serves a potential new drug target for liver fibrosis.

[Surveillance and analysis on the pathogenic features of Salmonella in Guangdong province in 2010].

OBJECTIVE: In order to better understand the nature of Salmonella infection in diarrheal patients in Guangdong province, the study analyzed the serum types, antibiotic resistance and molecular determinants of the isolated Salmonella strains. METHODS: In year 2010, 8405 diarrhea patients from 16 surveillant hospital in Guangzhou, Zhongshan, Dongguan, Zhuhai, Maoming, Yangjiang and Jiangmen cities in Guangdong province, were recruited in the study. A total of 8405 fecal specimen were collected and subjected to Salmonella isolation and culture. The isolated Salmonella strains were further analyzed via serotyping, antimicrobial susceptibility testing, and PFGE. The χ(2) test was applied to compare the differences between the isolated Salmonella strains in different seasons and districts. BioNumerics software was used to analyze the PFGE results in order to determine the correlation between different Salmonella strains. RESULTS: The positive rate of the surveillant Salmonella in Guangdong province was 3.58% (301/8405) in 2010; with the gender ratio at 1.34:1 (166/124). Salmonella infection was found in all age groups, and most in infants, accounting for 57.48% (173/301). The isolated rates of Salmonella were separately 3.48% (61/1751), 4.97% (134/2695), 3.08% (73/2370) and 2.08% (33/1589) in the four seasons; and the difference was statistically significant (χ(2) = 27.29, P < 0.01). The isolated rates of Salmonella in different regions were as follows: Zhuhai 15.43% (25/162), Maoming 7.53% (18/239), Dongguan 6.51% (39/599), Yangjiang 3.64% (14/385), Zhongshan 3.03% (70/2309), Guangzhou 2.90% (126/4349) and Jiangmen 2.49% (9/362). The difference between regions was statistically significant (χ(2) = 100.75, P < 0.01). Except one strain of the isolated Salmonella cannot be serotyped, the other 300 strains were divided into 42 serotypes, of which Salmonella typhimurium and Salmonella enteritidis were dominant, account for 45.18% (136/301) and 10.96% (33/301) respectively. Although over 85% of Salmonella were sensitive to cephalosporin, ACSSuT resistance patterns (defined as resistance to at least ampicillin, chloramphenicol, streptomycin, sulfamethoxazole and tetracycline) reached 34.88% (105/301), the highest resistant rate was found in serotype Salmonella typhimurium, as high as 65.44% (89/136). 136 strains of Salmonella typhimurium were divided into 51 PFGE types, showed great genetic diversity. 33 strains of Salmonella enteritidis were divided into 18 PFGE types. The strains with same PFGE pattern may have different drug-resistant patterns, and vice versa. CONCLUSION: Salmonella typhimurium and Salmonella enteritidis were the dominant serotypes causing infectious diarrhea in Guangdong province. Cephalosporin was the primary choice in clinical medicine. However, Salmonella typhimurium was resistant to drug most seriously in Guangdong province. There was no significant correlation between Salmonella resistance patterns and PFGE type.

Genomic Epidemiology of Imported Cases of COVID-19 in Guangdong Province, China, October 2020 - May 2021.

Objective: The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been engendering enormous hazards to the world. We obtained the complete genome sequences of SARS-CoV-2 from imported cases admitted to the Guangzhou Eighth People's Hospital, which was appointed by the Guangdong provincial government to treat coronavirus disease 2019 (COVID-19). The SARS-CoV-2 diversity was analyzed, and the mutation characteristics, time, and regional trend of variant emergence were evaluated. Methods: In total, 177 throat swab samples were obtained from COVID-19 patients (from October 2020 to May 2021). High-throughput sequencing technology was used to detect the viral sequences of patients infected with SARS-CoV-2. Phylogenetic and molecular evolutionary analyses were used to evaluate the mutation characteristics and the time and regional trends of variants. Results: We observed that the imported cases mainly occurred after January 2021, peaking in May 2021, with the highest proportion observed from cases originating from the United States. The main lineages were found in Europe, Africa, and North America, and B.1.1.7 and B.1.351 were the two major sublineages. Sublineage B.1.618 was the Asian lineage (Indian) found in this study, and B.1.1.228 was not included in the lineage list of the Pangolin web. A reasonably high homology was observed among all samples. The total frequency of mutations showed that the open reading frame 1a (ORF1a) protein had the highest mutation density at the nucleotide level, and the D614G mutation in the spike protein was the commonest at the amino acid level. Most importantly, we identified some amino acid mutations in positions S, ORF7b, and ORF9b, and they have neither been reported on the Global Initiative of Sharing All Influenza Data nor published in PubMed among all missense mutations. Conclusion: These results suggested the diversity of lineages and sublineages and the high homology at the amino acid level among imported cases infected with SARS-CoV-2 in Guangdong Province, China.

Phenotypic and genotypic characterization Vibrio cholerae O139 of clinical and aquatic isolates in China.

To enhance the understanding of epidemiological impact of environmental Vibrio cholerae O139 strains, we characterized 10 clinical and 20 environmental isolates collected from human clinical samples and Pear River estuary during 2006 to 2008. Isolates were tested by PCR for eight virulence genes: cholera toxin (ctxA), zonula occludens toxin (zot), accessory cholera enterotoxin (ace), hemolysin (hlyA), NAG-specific heat-stable toxin (st), toxin-coregulated pilus (tcpA), outer membrane protein (ompU), and regulatory protein genes (tcpI). Genetic relatedness was assessed by pulsed-field gel electrophoresis (PFGE), and antibiotic susceptibility was determined using disk diffusion. Seven of eight virulence markers were detected in six clinical isolates and one environmental isolate. One clinical and one environmental isolate were positive for six virulence markers. 60% clinical isolates showed multi-drug resistance to tetracycline (TET), Nalidixic acid (NAL), chloramphenicol (CHL), and ampicillin (AMP), 70% were resistant to Trimethoprim + Sulfamethoxazole (SXT), while only 35% environmental strains were resistant to SXT. PFGE analysis revealed that the isolates in this study were formed three clusters. Cluster III was more related to strains from diarrheal patients than the strains in other clusters. Different from the clinical strains, most environmental strains lacked CTX and TCP gene clusters. Most environmental strains possess a single resistance profile, while most clinical isolates show multidrug resistant. PFGE analysis indicated the cluster III has more possibility to become a potential pathogenic clonal cluster.

Occurrence and dietary exposure assessment of pentachlorophenol in livestock, poultry, and aquatic foods marketed in Guangdong Province, China: Based on food monitoring data from 2015 to 2018.

As a persistent organic pollutant, pentachlorophenol (PCP) has serious impacts on human health. However, its presence in animal source food products sold in the Guangdong Province (GD) of China, and the resultant dietary exposure have not been elucidated. To address this gap, 3,100 samples from seven food categories, including beef, pork, mutton, offals, broilers, hen eggs, and farmed freshwater fish, marketed throughout four geographical regions of GD, were collected from 2015 to 2018. Gas chromatography coupled with mass spectrometry was employed to detect PCP levels in these food matrices. PCP was found in all food categories, but the average contamination levels were low, ranging from 0.40 µg/kg wet weight (ww) (hen eggs) to 5.85 µg/kg ww (offals). However, higher concentrations of PCP were detected (P < 0.05) in animal source food from the North region. Additionally, a temporal declining trend was observed in this four-year consecutive survey. The estimated human dietary exposure of PCP to population groups, including the general population and subgroups (male and female, children, and adults), was found to be far below the permissible daily intake (3 µg/kg body weight). Therefore, the health impacts of PCP should be correspondingly low for local residents, based on current toxicological knowledge. Regional exposure patterns varied due to different extents of contamination in the four areas, and pork, broilers, and freshwater fish were the major sources of dietary PCP exposure. PRACTICAL APPLICATION: As a persistent organic pollutant, pentachlorophenol (PCP) has serious impacts on human health. However, its presence in animal source food products sold in Guangdong Province of China, and the resultant dietary exposure have not been elucidated. In this study, we conducted an in-depth investigation on the occurrence of PCP in major foodstuff categories, including beef, pork, mutton, broilers, offals, hen eggs, and farmed freshwater fish, marketed in all 21 prefecture-level divisions of Guangdong Province, in order to provide integral insights for regulatory authorities.

Heterogeneous nuclear ribonucleoprotein A2/B1 is a negative regulator of human breast cancer metastasis by maintaining the balance of multiple genes and pathways.

BACKGROUND: Heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 is an important RNA-binding protein that affects the RNA processing, splicing, transport and stability of many genes. hnRNPA2/B1 is expressed during proliferation and metastasis of various cancer types and promotes such processes. However, the precise role and mechanism of hnRNPA2/B1 in breast cancer remain unclear. METHODS: The association of hnRNPA2/B1 with breast cancer metastasis was assessed using tissue chips, mouse models and publicly available data. The role and mechanism of hnRNPA2/B1 in breast cancer metastasis were studied in cell lines and mouse models. FINDINGS: In contrast to other cancer research findings, hnRNPA2/B1 expression was negatively correlated with breast cancer metastasis. hnRNPA2/B1 inhibited MDA-MB-231 triple-negative breast cancer (TNBC) cell metastasis in vitro and in vivo. hnRNPA2/B1 knockout activated ERK-MAPK/Twist and GR-beta/TCF4 pathways but inhibited STAT3 and WNT/TCF4 signalling pathways. Profilin 2 (PFN2) promoted breast cancer cell migration and invasion, whereas hnRNPA2/B1 bound directly to the UAGGG locus in the 3'-untranslated region of PFN2 mRNA and reduced the stability of PFN2 mRNA. INTERPRETATION: Our data supported the role of hnRNPA2/B1 in tumour metastasis risk and survival prediction in patients with breast cancer. The inhibitory role of hnRNPA2/B1 in metastasis was a balance of downstream multiple genes and signalling pathways. PFN2 downregulation by hnRNPA2/B1 might partly explain the inhibitory mechanism of hnRNPA2/B1 in breast cancer metastasis. Therefore, hnRNPA2/B1 might be used as a new prognostic biomarker and valuable molecular target for breast cancer treatments.

A 25-bp ancient spliceosomal intron in the TvRab1a gene of Trichomonas vaginalis.

Spliceosomal introns play a key role in eukaryotic genome evolution and protein diversity. A large Rab GTPase family has been identified in a unicellular eukaryote Trichomonas vaginalis. However, the characteristics of introns in Rab genes of T. vaginalis have not been investigated previously. In this study, we identified a 25-bp spliceosomal intron in the T. vaginalis Rab1a (TvRab1a) gene, the smallest intron in T. vaginalis to be characterized to date. This intron contains a canonical splice site at both 5' (GT) and 3' (AG) ends, and a putative branch-point sequence (TCTAAC) that matches the Trichomonad consensus sequence of ACTAAC except for the first nucleotide. The position and phase of the TvRab1a intron are evolutionarily conserved in Rab1 homologous genes across at least five eukaryotic supergroups, including Opisthokonta, Amoebozoa, Excavata, Chromalveolata, and Plantae. These results strongly suggest that the TvRab1a intron is likely to be an ancient spliceosomal intron, and it can therefore be used as a phylogenetic marker to evaluate particular eukaryotic groupings. Identification and characterization of the TvRabla intron may provide an insight into the evolution of the large Rab repertoire in T. vaginalis.

[Molecular characters of epidemic cerebrospinal W135 Neisseria meningitidis strain firstly isolated in Guangdong province].

OBJECTIVE: To analyze the molecular characters of the W135 Neisseria meningitidis strain firstly isolated from patients in Guangdong province. METHODS: Biochemical profile by using the API NH system (bio-Merieux, France) was used for confirmation,and sero-grouping of the meningococcal isolates including one serogroup W135, one serogroup C and three serogroups of a Neisseria meningitidis isolated from patients in Guangdong province in recent two years were performed. The subtype was determined after amplifying porA and porB respectively from the genome DNA of Neisseria meningitidis. Multilocus sequence typing (MLST) was performed for determining the allele profiles and the sequence types (STs). The polygenetic tree was obtained by analyzing the allele profiles with program Splits tree online. The molecular characters of the serogroup W135 Neisseria meningitidis was analyzed by its evolution relationship and the variable regions in porA and porB which encoding the outer membranes proteins (OMPs). RESULTS: The subtype determined by porA variable regions of the serogroup W135 Neisseria meningitidis was P1.5,2, which was one of the most invasive types. The types of variable regions (VRs) I, IV, V, VII with porB were 1, 1, 1, 17, and there was no VI and VIII in porB. The allele profile of the W135 strain in this study was 2, 123, 4, 3, 8, 4, 6, and its sequence type was ST-2960, which belonged to ST-11/ET-37 clone complex. The subtypes of the serogroup C and serogroup A strains were P1.20, while their types of VR IV were all 7, and they all hadn't VR VII in porB. The strain serogroup C belonged to ST-4821 clone complex, and the 3 serogroup A strains belonged to ST-5 clone complex. CONCLUSION: The molecular character of the serogroup W135 Neisseria meningitidis should be the same with the strains isolated in foreign country, and be different from the epidemic types in the area. This serogroup W135 Neisseria meningitis isolated from patients in Guangdong for the first time was thought to be a new type appearing in the local area.

[Investigation of human metapneumovirus in children with acute respiratory tract infections in Guangzhou areas].

OBJECTIVE: To find out the status of human metapneumovirus (hMPV) infection in children under 14 years old with acute respiratory tract infections (ARI) in Guangzhou, analyze the epidemiology and clinical characteristics among the hMPV-infected children, and provide some basis for research of hMPV. METHODS: All 521 throat and pharyngeal swabs were collected among the children with acute respiratory tract infections in outpatient departments and those admitted to the wards from September 2006 to August 2008. Then total nucleic acid was extracted from respiratory specimens. The 213 nucleosides of nucleoprotein gene were detected by RT-PCR and 16 strong positive samples were picked to compare with the sequence of hMPV in GenBank after the sequence of the amplification products were determined. Then applied statistical analysis to the data of the collected patients. RESULTS: All 521 samples were detected by RT-PCR, and confirmed that N gene was positive in 39 samples with a detection rate of 7.49%, and the peak time was in October and April. The 16 amplification products were compared by using the analysis of gene sequence. The nucleocapsid protein (N) gene similarity to BJ1897 of Beijing was up to 99%, and to AY550156 of Thailand was up to 97%, genotype B was the most common genotype. CONCLUSION: There existed hMPV infection in children acute respiratory system diseases in Guangzhou areas, in which the children under the age of 6 years were accounted for the main group, however there was no difference in gender. The main symptoms of the patients with hMPV infection were high fever and cough symptom of catarrh. Co-infections other than respiratory virus with hMPV were detected as 41.03% of positive samples.

Levels, congener profiles, and dietary intake assessment of polychlorinated dibenzo-p-dioxins/dibenzofurans and dioxin-like polychlorinated biphenyls in beef, freshwater fish, and pork marketed in Guangdong Province, China.

Persistent organic pollutants such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) consisting of non-ortho and mono-ortho PCBs are suggested to be very hazardous and have adverse effects on human health. However, their levels and congener profiles in retail foods marketed in Guangdong Province of China have not been elucidated thus far. Thus, in this study, 226 individual samples of beef, freshwater fish, and pork marketed across four regions of Guangdong Province were randomly collected during 2013-2015 to determine their levels of PCDD/Fs and DL-PCBs. The results showed that the total toxic equivalency quantities (TEQs) of most samples were below the maximum limits except for the 26 samples collected from the vicinities of pollution areas. The median total TEQs of these three categories were 0.174, 0.488, and 0.113pgTEQ/g fw, respectively, which indicated that the contamination status of the studied foods was not serious. For congener profiles, significantly different patterns were observed in three food groups, but with the same major TEQ contributors being 2,3,4,7,8-PeCDF in beef, freshwater fish, and pork. Regional differences of congener profiles in each food group were also found in this study, which might be attributed to the regionally different distributions of PCDD/Fs and DL-PCBs in environment media. The dietary exposures of four population subgroups (girls, boys, male adults, and female adults) to PCDD/Fs and DL-PCBs via three food groups were estimated to assessed the potential risks. They were all lower than the provisional tolerable monthly intake (PTMI, 70pgTEQ/kgbw/month) established by Joint FAO/WHO Expert Committee on Food Additive. In these food categories, the exposure to PCDD/Fs and DL-PCBs via freshwater fish was the highest one, which accounted for about 20% of PTMI, indicating that it was the major route to expose dioxin compounds.

[Identifying group G beta-hemolytic Streptococci strains by 16S rDNA sequencing].

OBJECTIVE: To identify the DNA sequences of 26 beta-hemolytic group G streptococci strains isolated from the swabs of patients in a glomerulonephritis outbreak event. METHODS: API20 Strep system and 16S rDNA sequencing were performed on all of the 26 isolated strains respectively. The dendrogram based on the analysis of the 16S rDNA sequences of four groups of G streptococci strains was constructed by the neighbor-joining method and boot-strap test. RESULTS: The API20 Strep system failed to identify the strains with less than 62% of success rates. All of the 26 group G beta-hemolytic streptococci isolates were identified as Streptococcus anginosus by the 16S rDNA sequencing, with more than 97% of success rates. The dendrogram illustrated that the four groups of G streptococci strains were clustered at the same branch with Streptococcus anginosus. CONCLUSION: The 16S rDNA sequencing has unique advantages over the phenotypic methods. It can provide detailed information of nucleotides and identify species of beta-hemolytic G group streptococci.

Ephrin-B2/Fc promotes proliferation and migration, and suppresses apoptosis in human umbilical vein endothelial cells.

Tumor growth and metastasis are angiogenesis dependent. Angiogenic growth involves endothelial cell proliferation, migration, and invasion. Ephrin-B2 is a ligand for Eph receptor tyrosine kinases and is an important mediator in vascular endothelial growth factor-mediated angiogenesis. However, research offer controversial information regarding effects of ephrin-B2 on vascular endothelial cells. In this paper, proteome analyses showed that ephrin-B2/Fc significantly activates multiple signaling pathways related to cell proliferation, survival, and migration and suppresses apoptosis and cell death. Cytological experiments further confirm that ephrin-B2/Fc stimulates endothelial cell proliferation, triggers dose-dependent migration, and suppresses cell apoptosis. Results demonstrate that soluble dose-dependent ephrinB2 can promote proliferation and migration and inhibit apoptosis of human umbilical vein endothelial cells. These results also suggest that ephrinB2 prevents ischemic disease and can potentially be a new therapeutic target for treating angiogenesis-related diseases and tumors.

[Analysis of HLA-B locus gene polymorphism in Sichuan Yi ethnic group and Xinjiang Uygur ethnic group].

The polymorphism of HLA-B alleles in Sichuan Yi and Xinjiang Uygur population was investigated using the PCR-SSP method. Twenty one alleles were detected in HLA-B loci in 106 Sichuan unrelated Yi healthy subjects. Of them, B*40, B*15 and B*51 were the most common alleles with an allele frequency of 0.1981, 0.1368, 0.1274, respectively; while B*47, B*44, B*18, B*57 and B*78 were the rare alleles with an allele frequency of 0.0189, 0.0142, 0.0094, 0.0047 and 0.0047, respectively. The distribution of HLA-B allele frequencies in Sichuan Yis was between Southern Han and Northern Han. In 110 Xinjiang unrelated healthy Uygur subjects, 27 alleles were detected in HLA-B loci. Of them, B*35 and B*51 were the most common alleles with an allele frequency of 0.1136 and 0.1136, respectively; while B*41, B*56 and B*78 were the rare alleles with a frequency of 0.0045, 0.0045 and 0.0091, respectively. Frequencies of "Caucasoid origin" HLA alleles such as B*08, B*35 and B*50 in Xinjiang Uygurs were higher than other ethnic groups in China. The result of chi2 tests showed that the distributions of HLA-B alleles in Yi and Uygur ethnic groups were in Hardy-Weinberg equilibrium. Heterozygosity (H), discrimination power (DP) and probability of paternity exclusion (EP) of HLA-B locus from Sichuan Yi ethnic group were computed to be 0.8977, 0.9661 and 0.8009; and those from Xinjiang Uygur ethnic group were 0.9372, 0.9857 and 0.8732. The data obtained in this study on the distributions of HLA-B alleles in the Sichuan Yi and Xinjiang Uygur population provide important group genetics information for forensic and paternity tests to estimate the frequency of a DNA profile in these two populations, and can be used in transplant matching, anthropological and disease association studies.

Development of a semi-quantitative food frequency questionnaire for middle-aged inhabitants in the Chaoshan area, China.

AIM: This paper aims to develop a data-based semi-quantitative food frequency questionnaire (SQFFQ) covering both urban and rural areas in the Chaoshan region of Guangdong Province, China, for the investigation of relationships between food intake and lifestyle-related diseases among middle-aged Chinese. METHODS: We recruited 417 subjects from the general population and performed an assessment of the diet, using a 3-d weighed dietary record survey. We employed contribution analysis (CA) and multiple regression analysis (MRA) to select food items covering up to a 90% contribution and a 0.90 R(2), respectively. The total number of food items consumed was 523 (443 in the urban and 417 in the rural population) and the intake of 29 nutrients was calculated according to the actual consumption by foods/recipes. RESULTS: The CA selected 233, 194, and 183 foods/recipes for the combined, the urban and the rural areas, respectively, and then 196, 157, and 160 were chosen by the MRA. Finally, 125 foods/recipes were selected for the final questionnaire. The frequencies were classified into eight categories and standard portion sizes were also calculated. CONCLUSION: For adoption of the area-specific SQFFQ, validity and reproducibility tests are now planned to determine how the combined SQFFQ performs in actual assessment of disease risk and benefit.

[Infiltration of DCs and CD4+ T cells in muscle after DNA immunization].

OBJECTIVE: In order to get a better understanding of the mechanism of DNA initiating specific cytotoxicity T lymphocyte (CTL) immune response, we observed the local infiltration in injection site at different time after DNA immunization and further studied the characters of infiltration cells. METHODS: The local infiltration in injection sites was observed by HE staining at 6 h, 12 h and 1-6 days after DNA immunization. Infiltration cells were further studied with the mice dendritic cells marker CD205, T lymphocyte marker CD4 and CD8 by immunohistological methods. RESULTS: phAFP injection into mouse muscle led to a local infiltration. Infiltrates reached peak at 3-6 days after injection and appeared in several discrete clusters within the muscles. The predominant cell types found in infiltrates were macrophage-like cells and lymphocytes. Immunohistological staining revealed CD205+ and CD4+ cells. CD4+ cells could be detected in any of the injected muscles. CD205+ cells were only seen at 24 h to day 3, appearing later and disappearing earlier than CD4+ cells. However, CD8+ immunostaining positivity could not be found. CONCLUSION: Our findings indicate that the character of local infiltration after DNA immunization is different from the inflammation of injection. The recruitment of CD205+ to the injection site suggests that DCs and Th cells play an important role in DNA immunization.

Expression of class I MHC molecule, HSP70 and TAP in human hepatocellular carcinoma.

AIM: To demonstrate whether class I MHC molecule, transporter associated with antigen processing (TAP), and heat-shock proteion70 (HSP70) expressed in liver cancer cells before the design and construction of CTL vaccine against hepatocellular carcinoma (HCC). METHODS: We studied 30 HCC specimens by labeled streptavidin biotin (LSAB) method of immunohistochemistry. RESULTS: The results showed that the majority of HCC cells investigated naturally expressed class I MHC and TAP, which were different from other tumor cells. Furthermore, we found that HSP70 expressed not only in cellular cytoplasm, but also on the cell surface in HCC. CONCLUSION: Our findings indicate that our understanding about immune escape mechanisms employed by HCC cells may be further improved. It is important to design and construct CTL vaccine against HCC.