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Background: Gut microbiota plays a significant role in the colorectal cancer (CRC) process. Ectopic colonization of multiple oral bacteria is reportedly associated with CRC pathogenesis and progression, but the details remain unclear. Methods: We enrolled a cohort of 50 CRC patients and 52 healthy controls from an East China population. Taxonomic and functional analysis of the fecal microbiota were performed using 16S rDNA (50 + 52 samples) and shotgun metagenomic sequencing (8 + 6 samples), respectively, with particular attention paid to gut‐colonized oral bacteria. Results and Conclusions: The results showed more detected bacterial species but lower species evenness within the samples from CRC patients. To determine the specific bacteria enriched in each group, we analyzed their possible protective, carcinogenic, or opportunistic roles in the CRC process. Among the ectopic oral bacteria, we observed a significant increase in the abundance of Fusobacterium and decreased abundance of Prevotella and Ruminococcus in the CRC group. Main differences in the functional composition of these two groups were related to energy metabolism and biosynthesis, especially the glycolytic pathway. Furthermore, we validated the colonization of Fusobacterium nucleatum subsp. animalis within CRC tissues and studied its impact on the host intestinal epithelium and tumor cells. With high selectivity for cancerous tissues, this subspecies promoted CRC cell proliferation and induced potential DNA damage. [ABSTRACT FROM AUTHOR]

Three new species of Russula section Ingratae, found in Guizhou and Jiangsu Provinces, southern China, are proposed: R. straminella, R. subpectinatoides and R. succinea. Photographs, line drawings and detailed morphological descriptions for these species are provided with comparisons against closely-related taxa. Phylogenetic analysis of the internal transcribed spacer (ITS) region supported the recognition of these specimens as new species. Additionally, R. indocatillus is reported for the first time from China and morphological and phylogenetic data are provided for the Chinese specimens. [ABSTRACT FROM AUTHOR]

The Xinlu Sn‐polymetallic ore field is located in the western Nanling Polymetallic Belt in northeastern Guangxi, South China, where a number of typical skarn‐, hydrothermal vein‐type tin deposits have developed. There are two types of Sn deposits: skarn‐type and sulfide‐quartz vein‐type. The tin mineralizations mainly occur on the south side of the Guposhan granitic complex pluton and within its outer contact zone. To constrain the Sn mineralization age and further understand its genetic links to the Guposhan granitic complex, a series of geochronological works has been conducted at the Liuheao deposit of the ore field using high‐precision zircon SHRIMP U‐Pb, molybdenite Re‐Os, and muscovite Ar‐Ar dating methods. The results show that the biotite‐monzogranite, which is part of the Xinlu intrusive unit of the Guposhan complex pluton, has a SHRIMP U‐Pb zircon age of 161.0 ± 1.5 Ma. The skarn‐type ore has a 40Ar‐39Ar muscovite plateau age of 160 ± 2 Ma (same as its isochron age), and the sulfide‐quartz vein‐type ore yields an Re‐Os molybdenite isochron age of 154.4 ± 3.5 Ma. The magmatic‐hydrothermal geochronological sequence demonstrated that the hydrothermal mineralization took place immediately following the emplacement of the monzogranite, with the skarn metasomatic mineralization stage predating the sulfide mineralization stage. Geochronologically, we have compared this ore field with 26 typical Sn deposits distributed along the Nanling Polymetallic Belt, leading to the suggestion of the magmatic‐metallogenic processes in the Xinlu ore field (ca. 161–154 Ma) as a component of the Early Yanshanian large‐scale Sn‐polymetallic mineralization event (peaked at 160–150 Ma) in the Nanling Range of South China. Petrogenesis of Sn‐producing granite and Sn‐polymetallic mineralization were probably caused by crust–mantle interaction as a result of significant lithospheric extension and thinning in South China in the Late Jurassic. [ABSTRACT FROM AUTHOR]

Many colonies of macaques ( Macaca fascicularis and Macaca mulatta) are maintained in China, especially in Guangxi and Guizhou. A total of 803 fresh stool samples infected with Entamoeba were obtained from three big colonies of macaques located in southwest China. The samples were examined for the presence of five Entamoeba species using PCR. Entamoeba nuttalli, Entamoeba dispar, Entamoeba coli, and Entamoeba chattoni infections were detected, but Entamoeba histolytica infection was not. This study is the first to report on the prevalence of E. nuttalli in wild macaques from China. Eighteen E. nuttalli isolates and five E. dispar isolates were obtained by culturing the samples in Tanabe-Chiba medium. The serine-rich protein (SRP), ribosomal RNA (rRNA), hexokinase (HXK), glucose-6-phosphate isomerase (GPI), and phosphoglucomutase (PGM) genes of E. nuttalli isolates were compared with other reported isolates. The results showed clear differences among the Chinese E. nuttalli isolates and other isolates based on the SRP gene sequences. However, HXK, GPI, and PGM genes of these strains were similar to those of other isolates. The rRNA genes of E. coli and E. chattoni were also amplified and analyzed from these samples. The results suggested that host species might be a more important factor than geographic location in amebic genetic diversity. [ABSTRACT FROM AUTHOR]

A few PCR-based DNA typing methods using repetitive elements contained within both protein-coding genes and noncoding DNAs have been reported for Entamoeba histolytica over the years. The serine-rich E. histolytica protein and tRNA-linked short tandem repeats (STRs) are most commonly used to investigate the relationship between parasite genotype and E. histolytica infection outcome. Many E. histolytica infections in China have been reported; however, little genome information has been provided. In the current paper, five Chinese E. histolytica samples were reported: three amoebic liver abscess cases, one combined case and one asymptomatic case. Our study is the first to report on the DNA typing information of E. histolytica in China. We included two city, one imported, and two country cases. Sequence analysis of serine-rich protein genes confirmed the presence of seven sequence types in five isolates. The STRs amplified from the samples revealed five STR variations in the A-L, four in the N-K2, and R-R loci, three in D-A, S-D and S-Q loci. Two country patients were found to have a different outcome of infection with the same genotypes of E. histolytica, whereas in a city case, one E. histolytica strain had led to different outcome of the infection in one patient. Analyses of the results suggest that more genome information of E. histolytica strains from China through accurate methods is needed to interpret how the parasite genome plays a role in determining the outcome of E. histolytica infections. [ABSTRACT FROM AUTHOR]

China and other rapidly developing economies face the dual challenge of substantially increasing yields of cereal grains while at the same time reducing the very substantial environmental impacts of intensive agriculture. We used a model-driven integrated soil-crop system management approach to develop a maize production system that achieved mean maize yields of 13.0 t ha-1 on 66 on-farm experimental plots-nearly twice the yield of current farmers' practices-with no increase in N fertilizer use. Such integrated soil-crop system management systems represent a priority for agricultural research and implementation, especially in rapidly growing economies. [ABSTRACT FROM AUTHOR]

Entamoeba nuttalli infection is highly prevalent in captive and wild macaques. A recent study suggested that the genetic factor of host macaques was correlated with the genotypes of E. nuttalli isolates. This study focused on the correlation between the rhesus macaque host major histocompatibility complex gene and E. nuttalli infection. Thirty-nine stool samples were obtained from Mount Qing-ling (Guizhou Province, China). Polymerase chain reaction analysis detected the infection rate of E. nuttalli , Entamoeba coli , and Entamoeba chattoni as 69.23%, 69.23%, and 87.18%, respectively. A new Serine-rich Protein genotype was detected, and the rRNA of E. nuttalli isolates from Mount Qian-ling was completely identical to the GY4 strain. In the distance-based neighbor-joining tree, Mamu-DRB1 , not Mamu-DPB or Mamu-B gene, was related to E. nuttalli infection. Mamu-DRB1 genes of rhesus macaques in Mounts Qian-ling and Long-hu were highly polymorphic, and the rhesus macaques with two major types of Mamu-DRB1 showed susceptibility to E. nuttalli infection. The Mamu-DRB1 gene analysis in this study indicated that the Mamu-DRB1 gene is an important factor that influences the susceptibility of E. nuttalli infection in Chinese Macaca mulatta. This study contributes to a better understanding of host susceptibility to Entamoeba. • Analysis of 76 stool samples from rhesus macaques in two provinces of China. • High prevalent (69.23%) of Entamoeba nuttalli in Mount Qing-ling's macaques • Sequence of Mamu-DRB1 , Mamu-DPB and Mamu-B genes in these macaques • Mamu-DRB1 genes were highly polymorphic in Mount Qian-ling and Long-hu's macaques • Mamu-DRB1 , not Mamu-DPB or Mamu-B gene, was related to E. nuttalli infection. [ABSTRACT FROM AUTHOR]

Chilo suppressalis (Walker) displays significant geographical differences in ecological preference that may be congruent with patterns of molecular variation. To test this, we collected and analysed 381 individuals of this species from cultivated rice at 18 localities in China during the rice-growing season of 2005–2006. We used four microsatellite DNA markers and four mitochondrial DNA gene fragments. We found that this species is highly differentiated, coupled with an estimated population expansion date of at least 60 000 bp. Phylogenetic analyses, Bayesian clustering, and phylogeographical analyses of statistical parsimony haplotype network consistently divided the populations into three clades: a central China (CC) clade, a northern plus northeastern China (NN) clade and a southwestern China (SW) clade. Analysis of molecular variance indicated a high level of geographical differentiation at different hierarchical levels [ FST for microsatellite markers, COI, COII, 16S and ND1 is 0.06004 ( P<0.0001), 0.27607 ( P<0.0001), 0.22949 ( P<0.0001), 0.19485 ( P<0.0001) and 0.29285 ( P<0.0001), respectively]. Isolation by distance appeared among the samples from within China ( r = 0.404, P = 0.0002); Nem values estimated using a coalescent-based method were small (< 2 migrants per generation), suggesting that the observed levels of differentiation are a result of migration–drift equilibrium. Our results imply that the genetic differentiation of this borer, which is approximately in accordance with its observed number of generations per year in different Chinese geographical regions, is probably attributed to climatic and/or geological events (e.g. the last glacial maximum) and subsequently strengthened by the domestication of rice. [ABSTRACT FROM AUTHOR]

Entamoeba nuttalli found in macaques is phylogenetically the closest species to Entamoeba histolytica and is potentially pathogenic. In this study, the prevalence of Entamoeba infections was examined in wild rhesus macaques by examining 73 and 90 fecal samples collected from two sites, Popa Taung Kalat (PTK) and Pho Win Taung (PWT), in Myanmar. The positive rates of E. nuttalli detected using PCR were 49% and 31% in PTK and PWT, respectively, but no infections of E. histolytica and E. moshkovskii were found. Entamoeba dispar was detected in 6% of samples only from PWT. Positive rates of E. chattoni and E. coli were both 70% in PWT and 67% and 79% in PTK, respectively. Six E. nuttalli strains from PTK and eight from PWT were obtained in the culture with xenic medium and then, one and two strains, respectively, were axenized and finally cloned. The genotypic analysis of serine-rich protein genes revealed two genotypes each in both sites. The genotypes found in five of six strains from PTK were similar to those from the strains found in Nepal, whereas the remaining one from PTK and two from PWT were similar to those obtained from macaques in China. The sequence of the 18S rDNA of strains with these four genotypes was identical to that of the strains from China. Six loci of tRNA-linked short tandem repeats were analyzed for further genotyping of the strains. Although there were two types in locus A-L in PTK isolates, one of each type for PTK and PWT was found in the other loci, including locus A-L in PWT strains. These results demonstrated that the E. nuttalli strains from Myanmar are closer to the strains from macaques in China rather than those from macaques in Nepal. • Entamoeba nuttalli is prevalent in wild rhesus macaques from two sites in Myanmar. • Its 18S rDNA sequence was identical to those from the rhesus macaques in China. • Four genotypes of serine-rich protein were found in 14 E. nuttalli strains. • E. nuttalli strains from each site had unique tRNA-short tandem repeat sequences. • E. nuttalli strains from Myanmar are closer to those from China than from Nepal. [ABSTRACT FROM AUTHOR]

Trichomonas vaginalis (Tv) is a flagellated protist parasite that infects the human urogenital tract. The symbiotic relationship between Tv and Mycoplasma hominis has been reported. Recent studies have identified a new Mycoplasma strain, Candidatus Mycoplasma girerdii (Ca. M. girerdii), present in the vaginal secretions of women and have shown that this strain may be related to trichomoniasis. Here, we evaluated the presence of Tv, M. hominis and Ca. M. girerdii in 312 clinical samples from adult women diagnosed with vaginitis in Zhangye, Gansu province, China. Among these samples, 94, 153, and 48 were Tv, M. hominis and Ca. M. girerdii positive, respectively. Moreover, Tv was highly frequent in 17–30-year-old women in this region. Forty samples (83.3%) positive for Ca. M. girerdii were also positive for Tv. Six Tv isolates were successfully cultured, including five isolates that showed symbiotic relationships with Mycoplasma. This is the first report to evaluate the genetic characteristics of Ca. M. girerdii in China and may therefore provide insights into the effects of Ca. M. girerdii on the reproductive health of women. [ABSTRACT FROM AUTHOR]

• Unveiled the nature of the long-term speculated hidden granite in Xidamingshan area, South China. • New data of hidden granite revealed the origin and associations with regional large-scale magmatism. • Confirmed the genetic links between the hidden granite and regional W-polymetallic mineralizations. Common understanding of pluton-related W-polymetallic mineralization is mainly based on studies in areas with exposed granitic plutons or plutons buried at shallow levels. However, there exist a large number of ore deposits that are considered to be associated with deeply hidden granitic plutons (deeper than 500 m). Their metallogenesis is not well documented due to lack of deep drilling and sampling. In this paper, we present a deeply hidden granitic pluton recently discovered by a kilometer-scale drilling project in the Xidamingshan Mountains area in western South China. The pluton, here refereed to Xidamingshan granitic pluton, underlies the Xidamingshan W-Zn-Pb-Ag-mineralized district. Petrographic examinations reveal that the hidden granite is biotite granite with partly hydrothermal alteration and that the upper part of the pluton is subjected to greisenization. Geochronological analyses indicate that the granite pluton was emplaced at the Late Cretaceous time with zircon U-Pb ages of 98.0 ± 1.0 Ma and 99.8 ± 0.9 Ma. The emplacement was subsequently followed by hydrothermal activity as indicated by muscovite 40Ar-39Ar ages of 93 ± 3 Ma and 92 ± 3 Ma. Re-Os dating of molybdenite yields an isochronal age of 95.9 ± 1.7 Ma (MSWD = 2.2). These ages indicate that the Xidamingshan mineralization is temporally related to the hidden granite. The granite is strongly peraluminous (A/CNK = 1.50 – 1.61) with high-K calc-alkaline affinity (ASI = 1.46 – 1.61) and shows enrichment in Rb, Ta, U, and K and depletion in Nb, P, and Ti. It contains muscovite and biotite but is lack of hornblende. It shows a steady correlation between P 2 O 5 and increasing SiO 2 , high Rb/Sr ratios (1.33 – 3.12), and high zirconium saturation temperature (average of 767 °C). The Xidamingshan granite is thus a typical S-type granite. Geochemical signature and negative ε Hf (t) values (-4.9 – −12.6) indicate that the hidden granite might have been generated by melting of crustal materials of argillaceous-depleted sedimentary rocks. Granites with such geochemical characteristics are known as having W-polymetallic mineralization specialization based on comparison with other ore-forming granites in South China. Significant W-polymetallic mineralization has been found within the thick Cambrian strata overlying the hidden granite pluton. Distribution of the related deposits demonstrates a typical zoning pattern from skarn-type W deposits, through vein-type Pb-Zn deposits, to vein-type Ag deposits. Given the combined evidences of metallogenic specialization of the source rocks for granitic magmas, geochronological coupling of the magmatism and hydrothermal activity, and the hydrothermal alteration and mineralization zoning, it is suggested that there exists a hydrothermal W-Zn-Pb-Ag mineralization system driven by the emplacement of the Late Cretaceous S-type hidden granite pluton. The findings of this study provide insights into future deep drilling and related ore exploration in regions with hidden granite in South China and the world. [ABSTRACT FROM AUTHOR]

The origin of fibrous calcite veins developed in organic-rich shales, has attracted great attentions. However the growth direction, formation temperature and stress state are still controversial. The calcite veins in organic-rich shale from lower Es3 to upper Es4 in the Jiyang Depression has been analyzed with electron backscatter diffraction technology (EBSD), which can characterize the microstructures and orientation of mineral crystals in situ. On the basis of core observation and microscopic identification of petrological characteristics, the longitudinal and horizontal profiles of calcite veins were measured by EBSD. Crystallographic information on calcite veins, obtained by pattern quality mapping, phase diagrams, grain distribution maps, Euler graphs, grain misorientations and pole figures, clarifies the origins of these veins. The results show that calcite crystals in calcite veins belong to the sharp-rhombohedral space lattice structure of the trigonal system. Calcite crystals have a preferred orientation on the longitudinal profile, while there is no obvious preferred orientation on the horizontal profile. On the longitudinal profile of calcite veins, the misorientation of calcite crystals is the cause of the interference colour and extinction difference of calcite crystals under orthogonal light. The crystal interference and extinction characteristics on both sides of middle line in calcite veins are different, indicating that the growth direction of calcite veins is syntaxial. A shallow burial environment is suggested for calcite veins initial forming by the evidence that crystal morphology of calcite in calcite veins is most in the shape of sharp-rhombohedron, and some of which have hexagonal prism shape. The average orientation difference of calcite veins on longitudinal and horizontal profiles indicates that the average orientation of calcite grains is inhomogeneous. The stress concentration of small grains is higher than that of large grains, and cracks are developed in the interior or on the border of calcite grains on the longitudinal profile, which indicates that calcite veins are formed in the stress environment of three directional extrusion circumstances. • Electron backscatter diffraction technique can be well used to characterize the crystal habit of fibrous calcite veins. • Calcite crystals in fibrous calcite veins belong to the sharp-rhombohedral space lattice structure of trigonal system. • Calcite veins are formed under the condition of low temperature and three-dimensional compressive stress. [ABSTRACT FROM AUTHOR]

Indosinian felsic volcanic rocks occurring in the Chongzuo area, Guangxi, were subject to prolonged weathering, which resulted in development of thick regolith hosting valuable ion-adsorption type REE resources. The figure below demonstrates a quantified REE eluviation-illuviation model for delineating the ion-exchangeable REEs enrichment pathway from source to sink. The source of ion-exchangeable REEs is mainly traced to a titanite + allanite + apatite assemblage, which together with other igneous minerals contributed REE ions to the weathering solution. After liberation of REEs by weathering, a large fraction of the rare earths is fixed by clay minerals (kaolinite + halloysite + illite assemblage) and the ions are present in an exchangeable form. A small fraction is adsorbed by Fe-Mn oxides and organic matter. REEs in zircon, monazite, and ilmenite are conserved; these minerals are the source of residual REEs in the regolith. • iREEs enrichment pathway in rhyolite regolith is delineated from source to sink. • Accessory mineral assemblage (titanite + allanite + apatite) is main source of iREEs. • The affinity of clay minerals to iREEs follows a halloysite > kaolinite > illite order. • There is formation preference for the felsic volcanic rocks-related iREEs deposits. Felsic volcanic rocks are an important source for generating ion adsorption-type rare earth element (REE) resources. To better understand the supergene enrichment of REEs related to felsic volcanic rock weathering, this study conducted an investigation of Indosinian felsic volcanic rocks from Guangxi, southwest China, which have been subjected to deep weathering. The weathering has formed large areas of thick regolith with the potential to host ion adsorption-type REE mineralization. The felsic volcanic rocks belong to the dacite–rhyolite series and are peraluminous, high-K, calc-alkaline, and REE-rich (325–376 ppm). Abundant REE-bearing accessory minerals are present in the felsic volcanic rocks, including titanite (average ΣREE = 15.1 wt%), allanite (average ΣREE = 14.9 wt%), and apatite (average ΣREE = 1510 ppm), and these three minerals contain an estimated 88.7% of the whole-rock REEs content. Significant REE enrichment is present in the felsic volcanic rock-derived regolith. A typical rhyolite-derived regolith profile has REE contents that increase from 376 ppm in the rhyolite to 1737 ppm in the regolith, representing an almost five-fold enrichment due to weathering. The REEs in the regolith are present in an ion-exchangeable form (iREEs), which accounts for 52%–87% of the total REEs present (TREEs). The occurrence of iREEs is closely linked to clay minerals, showing an affinity in the order halloysite > kaolinite > illite. Continuous operations of REEs by an eluviation–illuviation process from the source minerals (titanite + allanite + apatite) to sink minerals (kaolinite + halloysite + illite) results in an iREE-enriched zone in the middle and lower parts of the rhyolitic regolith. Notably, besides the studied Indosinian felsic volcanic rocks, there are multi-epochs of such lithology outcropped in South China. Their related iREEs mineralizations, however, are preferentially developed in the weathered terrains of early Yanshanian and Indosinian felsic volcanic rocks, and not in those of the Yanshanian and late Yanshanian felsic volcanic rocks. A comparison of the mineralized and barren units indicates that the iREEs mineralization hosted in felsic volcanic rocks regolith is controlled by some key endogenic and exogenic ore-forming factors. High initial REE concentrations in the unaltered felsic volcanic rocks, a suitable climate, and a relatively quiescent tectonic setting are favorable for the formation and preservation of iREEs mineralization. [ABSTRACT FROM AUTHOR]

Occurrence characteristics of antibiotics in the source water of the Nanjing section of the Yangtze River were analyzed preliminarily by solid-phase extraction and high-performance liquid chromatography-tandem mass spectrometry (SPE-HPLC-MS/MS). The results showed that the cumulative concentration of 16 sampling points ranged from 13.37 ng·L -1 to 780.5 ng·L -1 , with an average concentration of 92.95 ng·L -1 . Four sulfonamides, three fluoroquinolones, one tetracycline, five macrolides, and one chloramphenicol antibiotic were detected with average concentration ranging from 0.14 ng·L -1 to 49.91 ng·L -1 ,including enrofloxacin (ERX) and clarithromycin (CLR) with the highest detection rate of 100%, and clindamycin (CLI) with the highest concentration of 739.44 ng·L -1 . Overall, the concentration levels of antibiotics in the Nanjing section of the Yangtze River were low compared with other rivers and lakes in China. The risk assessment results showed that the largest cumulative risk of S2 was 0.31, and the environmental risk of sulfamethoxazole (SMX), doxycycline (DOX), and roxithromycin (ROX) had lower risk levels;the health risk indexes of nine antibiotics for different age groups were between 2.22×10 -6 and 4.86×10 -3 , while CLI and DOX are the main potential health risk factors for humans.

This study is the first to isolate an Entamoeba histolytica strain from Chinese amoebic patients and to conduct a detailed examination of its virulence. A fecal sample that contains cysts of E. histolytica was obtained from Guangxi province. The sample was cultured axenically and then cloned by limiting dilution, and named as XLAC. In vitro and in vivo tests were conducted to evaluate the virulence of the Entamoeba isolate. The E. histolytica strain XLAC was successfully cloned and cultured axenically. DNA regions that contain hexokinase, glucose-6-phosphate isomerase, phosphoglucomutase, and heavy subunit of lectin genes were amplified by PCR. The PCR products were then sequenced. Virulence analysis suggested that the XLAC strain was similar to the HM1:IMSS strain at the genetic level. In vitro and in vivo tests also implicated these strains to be similar. These findings may be attributed to the low expression levels of pathogenic genes obtained through realtime PCR. The XLAC strain restored its virulence after it was injected into hamster liver. This study may be a good model for studying virulence changes in E. histolytica.

Long-tailed macaques (Macaca fascicularis) are bred in China for export and for use in experiments. Entamoeba infections in captive long-tailed macaques were surveyed in one of the biggest colonies located in Guangxi Province, China. One stool sample was obtained from each of the 152 different cages representing >3,000 macaques in the colony. The samples were examined by PCR for five Entamoeba species. The number of detected Entamoeba coli infections comprised 94% of the samples, 93% for Entamoeba chattoni, and 83% for Entamoeba dispar. In contrast, Entamoeba histolytica and Entamoeba nuttalli were not detected. Six isolates of E. dispar were obtained by culture in Tanabe-Chiba medium. Analysis of serine-rich protein genes in these isolates showed two genotypes, one of which is identical to that of the E. dispar SAW760 strain in humans. This suggests transmission of E. dispar between humans and nonhuman primates. These results demonstrate that Entamoeba infections are common, but virulent Entamoeba species are absent in this colony. This work also confirms the need for monitoring with PCR-based identification of Entamoeba species for captive macaques in breeding colonies to ensure animal health and protection of humans from zoonotic hazards.

This study aimed to determine the genotypes of NSP4 in children with acute rotavirus diarrhea and evaluate serum antibody titers to NSP4 in different age groups in Shanghai, China. A total of 171 stool specimens were collected from hospitalized patients < or =5 years of age who had acute rotavirus diarrhea between January 2003 and December 2006. Serum samples were collected from healthy individuals, including 200 for 0-60 months of age and 30 for over 5 years of age. NSP4-B type was the single predominant genotype during 2003-2006 in Shanghai. The titers of NSP4 specific IgG antibody increased with age after birth and peaked during 12-23 months of age, thereafter dropping to a level as low as that in the first 5 months of age. However, high levels of antibody against whole rotavirus were maintained in older children over 5 years of age and in adults. Information on prevalence of NSP4 genotypes in this area of China provides useful data for formulating vaccine policy. Short antibody immune memory compared with that induced mainly by rotavirus structural proteins indicated the protective effect against rotavirus may not persist long term if a single NSP4 protein is applied as the rotavirus vaccine.

House dust mites are widely distributed in the human habitat and work environment and produce very powerful allergens. The most important allergy-causing mites found in homes worldwide are the house dust mites Dermatophagoides farinae and D. pteronyssinus and the storage mite Blomia tropicalis. It is important to know which mite species are present in a geographical area when performing diagnostic testing and prescribing immunotherapy. We classified the breeding situations of house dust mites in dwellings in northern China. Mites are detectable in March and their number increases from April or May, reaching a peak from July to September. The seasonal distribution of different acaroid mite species may differ: temperature, humidity, and eating habits were the major limiting factors determining species composition and diversity of acaroid mite communities in house ecosystems; comparing to the field and the forest, in human living area including house and working place, acaroid mites showed less bio-diversity.