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Background: Angiostrongylus cantonensis is a zoonotic public health concern that causes human severe eosinophilic meningitis in Southeast Asia and China. As a medically important intermediate host of A. cantonensis, Bellamya lithophaga (Gastropoda: Viviparidae) is often confused with other morphologically similar sibling species of genus Bellamya, such as B. aeruginosa and B. purificata in the past. Hence, the aim of the present study was to investigate evidences to discriminate these equivocal Bellamya species. Methods: This study was carried out by getting Bellamya snail samples from Fujian Province in the South-East of China. The snail morphological features,breeding grounds and phylogenetic relationship according to mitochondrial cytochrome c oxidase subunit I (COI) gene marker were analyzed. Results: Based on external morphology, radular shape and cusp formula, as well as major breeding environment, B. lithophaga could be distinguished from B. aeruginosa, B. purificata. The phylogenetic tree also unconfirmed that B. lithophaga belongs to a different genetic clade from other morphologically similar species. Conclusion: Our findings demonstrate the significant differences in B. lithophaga and other sibling species, which supports the traditional species delimitation in the genus Bellamya. [ABSTRACT FROM AUTHOR]

Sediments from two estuaries within Liaodong Bay, China, were examined for the effects on steroidogenesis using H295R human adrenocortical carcinoma cells. Total extracts (TE) isolated from sediments by Soxhlet extraction were separated into three fractions (F1, F2, and F3) using Florisil columns. After exposing H295R cells to each TE and fractions, the expressions of six steroidogenic genes (cytochrome P450 cholesterol side-chain cleavage [CYP11A], 3β-hydroxysteroid dehydrogenase type 1 [3β-HSD1], 3β-hydroxysteroid dehydrogenase type 2 [3β-HSD2], cytochrome P450 17-hydroxylase/17-20 lyase [CYP17], cytochrome P450 aromatase [CYP19], 17β-hydroxysteroid dehydrogenase [17β-HSD]), and the production of six steroid hormones (progesterone [PGT], 17-hydroxyprogesterone [17-HPT], testosterone [TTR], androstenedione [ADD], estrone [E1], and 17β-estradiol [17β-E2]) were measured. The gene expressions of CYP11A, CYP17, 3β-HSD2, and CYP19, and hormone productions of PGT, 17-HPT, TTR, ADD, E1, and 17β-E2 were significantly increased after exposure to F3 extracts from the Daliao River. In particular, greater concentrations of E1 (up to 48-fold) and 17β-E2 (up to 20-fold), as well as up-regulation of CYP19 gene expression (up to tenfold), were caused by exposure to the F3 fraction from the Daliao River, but not from the Daling River. Insight into the mechanism of action was obtained by use of principal component analysis (PCA), the results of which were consistent with unidentified constituents in F3 from the Daliao River activating the protein kinase A (PKA) pathway. This hypothesis was confirmed by reversal of the effects caused by F3 through a co-exposure of a PKA inhibitor (H89) and F3 extract. The H89 down-regulated CYP19 messenger RNA (mRNA) expression with concomitant lesser production of E1 and 17β-E2 in the co-exposure group, indicating unidentified constituents that could modulate estrogen synthesis, primarily through a mechanism of PKA activation. Environ. Toxicol. Chem. 2011;30:2793-2801. © 2011 SETAC [ABSTRACT FROM AUTHOR]

Abstract: Introduction: The limited information for effects of serum trace elements and genetic polymorphisms on lung cancer is available. Based on a hospital based case–control study, the epidemiological questionnaires were completed by face to face interview, and the gene polymorphisms were tested by RFLP–PCR, and serum trace metals were measured by atomic absorption spectrophotometer, and the data was analyzed by the logistic regressive models. Results: The high serum copper level (>1500ng/ml) or serum copper/zinc ratio (>1) was the risk factors of NSCLC (OR=3.10, 11.03, respectively), but the ORs of the higher serum Zn (>1200ng/ml), Se (>50ng/ml) or Cr3+ (>600ng/ml) for NSCLC were all significantly less than 0.20 (all p <0.01) indicating strong protection against NSCLC. While the OR of CYP 1A1 variants carriers with a higher serum Cu or Cu/Zn ratio level was around 3.38 and 12.59, respectively, the risk of CYP1A1 variants carriers with a higher serum Zn is 0.18, Se 0.04 or Cr3+ 0.28. Similarly, compared with the carriers of GSTM1 power with a lower serum Zn, Se or Cr3+, the OR of the carriers of GSTM1 null with a higher serum Zn, Se and Cr3+ was separately 0.16, 0.07 and 0.26, highlighting the protection against NSCLC. Conclusions: Our findings suggested that CYP1A1 or GSTM1 variants may significantly modify the associations between level of serum trace metals (Cu, Zn, Se or Cr) and NSCLC, indicating the intriguing pathogenesis of lung cancer. [Copyright &y& Elsevier]

Abstract: The anti-bacterial agent mequindox is widely used as an animal feed additive in China. Its potential effect on host cells, however, remains largely unknown. Here, we report that pig CYP3A22 represents an important metabolic enzyme in mequindox catalysis. Interestingly, we found that ectopic expression of CYP3A22 reversed the mequindox-induced G2 cell cycle accumulation in cultured pig hepatocytes. To further probe the catalytic mechanism of CYP3A22 in mequindox metabolism, we identified 2′-acetyl-hydroxylation as a major catalytic step of CYP3A22-dependent mequindox metabolism using LC–MS/MS spectrometry. Together, our study suggests that CYP3A22 plays an important role in mequindox metabolism via 2′-acetyl-hydroxylation. [Copyright &y& Elsevier]

Mitochondrial cytochrome b (Cytb) and partial control region (CR) DNA sequence of 165 individuals out of eight pig breeds (Laiwu Black, Dapulian Black, Licha Black, Yimeng Black, Yantai Black, Wulian Black, Luyan White and Changwei White) from Shandong province of China were sequenced to determine phylogenetic relationships and to what extent they were affected by modern commercial breeds (Landrace, Yorkshire and Duroc) in maternal lineage. The eight breeds from Shandong had lower maternal evolutionary divergence than the three commercial breeds. Additionally, they shared the same haplotype (T2) of Cytb. All these results suggest they may have originated from closely related maternal ancestors, if not from a single ancestor. The fact that haplotypes of Dapulian Black and Laiwu Black formed their own subclades, while those of other breeds of Shandong dispersed in the Asian clade of the tree based on CR, indicates that Dapulian Black and Laiwu Black are indigenous breeds with relatively independent maternal lineage, while the others have extensively gene flow with other breeds. Except in Luyan White, no European haplotypes were found in pig breeds from Shandong, demonstrating the maternal introgression from the modern commercial pigs has had no or very little impact on the breeds from Shandong. Comparatively, CR is more suitable to analyze the phylogenetic relationships of closely related groups, whereas the four SNPs of Cytb are useful to determine whether modern commercial breeds (Duroc, Landrace and sometimes Yorkshire) were used as dam in the breeding process of new breeds or synthetic lines in China. [ABSTRACT FROM AUTHOR]

Studies investigating possible associations between cytochrome P4501B1 (CYP1B1) polymorphisms and breast cancer risk have been inconsistent. We set out to ascertain whether there might be an association between polymorphisms in exon 2 (codon 119, G→T) and exon 3 (codon 432, G→C) of CYP1B1 and breast cancer in a Chinese Han population in the rural region of Ningxia. Using an allele-specific polymerase chain reaction method and direct DNA sequencing, the presence or absence of the two CYP1B1 polymorphisms was investigated. Genotype and allele frequencies were analyzed in breast cancer cases (n = 152) and healthy age-matched controls (n = 156). The odds ratio (OR) of 119G→T or 432G→C in breast cancer cases and controls was 3.3 (95% CI: 1.28 to 8.28) and 2.8 (95% CI: 1.04 to 7.51), respectively. In addition, the OR for people with both polymorphisms (119T and 432C) was 4.69 (95% CI: 1.97 to 11.19). Our results suggest that certain polymorphisms in the CYP1B1 gene might increase risk for breast cancer among Han Chinese, perhaps because they influence the efficiency of CYP1B1 bio-transformation of oestrogens or pro-carcinogens into DNA-reactive electrophiles that may act as cancer-initiating agents. [ABSTRACT FROM AUTHOR]

Centipeda minima is a medicinal plant reputed in China as a remedy for nasopharyngeal carcinoma (NPC). In this study, bioactivity-guided fractionation of the anti-NPC compound(s) from C. minima led to the isolation of 2β- (isobutyryloxy)florilenalin (IF), a sesquiterpene lactone. IF showed significant dose- and time- dependent inhibition on the growth of the human nasopharyngeal carcinoma epithelia cells (CNE). It induced apoptosis in CNE cells, as shown by the accumulation of sub-G1 cell population, DNA fragmentation and nuclear condensation, caspase-3 activation and PARP cleavage. Such induction was associated with the depletion of mitochondrial membrane potential (ΔΨm) and the release of cytochrome c to cytosol to regulate the expression of Bcl-2 family proteins. These activities led to the cleavage of caspases and the trigger of cell death process. Overall, IF in C. minima showed potent antiproliferative effect of C. minima on NPC cells, suggesting that the plant deserves more extensive investigation for its potential medicinal application. [ABSTRACT FROM AUTHOR]

A new species of horseshoe bat (Chiroptera: Rhinolophidae) is described from southwestern China. The presence of a wedge-shaped sella and pointed connecting process of the nose leaf aligns the new species to the landeri group in the Afro-Palearctic lineage of Rhinolophus. However, the new species is distinctly separable from these allopatrically distributed species by its noticeably larger body size. Other sympatric large-sized species of Rhinolophus have rounded connecting processes. Molecular systematic analyses based on mitochondrial cytochrome-b sequences confirmed the affinity of the new species to the Afro-Palearctic lineage, but in a clade most closely related to the ferrumequinum, fumigatus, and maclaudi groups. Of these species, only R. ferrumequinum ranges into Asia and overlaps in distribution with the new species. R. ferrumequinum is similar in general body size and external appearance; however, the new species is distinct in the characteristics of the nose leaf, skull, and baculum. The presence of a new species from southwestern China in the Afro-Palearctic lineage indicates a more complex historical biogeographic scenario within Rhinolophus than previously known. The difficulties found in allocating the new species to one of the phenetically described traditional species groups stress the convenience of using a phylogenetically based systematic organization of the genus Rhinolophus. [ABSTRACT FROM AUTHOR]

Cytochrome P4501A1 (CYP1A1) is a key enzyme in phase I bioactivation of polycyclic aromatic hydrocarbons (PAHs), which have potential reproductive toxicity. The aim of this study was to investigate the association of the CYP1A1 polymorphisms with male infertility in a Han-Chinese population. We genotyped two polymorphisms, CYP1A1*2A and CYP1A1*2C, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay in a hospital-based case–control study including 192 infertile patients with non-obstructive azoospermia or severe oligozoospermia and 226 fertile controls. We found that the genotype distribution of CYP1A1*2C was significantly different between the patients and the controls ( p = 0.019). Analysis showed that CYP1A1*2C AG genotype was associated with a significantly decreased risk of male infertility [odds ratio (OR) = 0.56, 95% confidence interval (95% CI) = 0.36–0.86, p = 0.005] compared with the AA genotype. A statistically significantly decreased risk of male infertility was found to be associated with the CYP1A1*2C AG genotype plus GG genotype compared with CYP1A1*2C AA genotype (OR = 0.60, 95% CI = 0.40–0.91, p = 0.011). No significant association was detected between CYP1A1*2A polymorphism and male infertility. Haplotypic analysis showed a significantly increased risk of male infertility associated with the C-A haplotype compared with the T-A haplotype (OR = 1.98, 95% CI = 1.27–3.09), indicating a synergic effect of the two polymorphisms. Our results suggest that the CYP1A1 polymorphisms may contribute to the pathogenesis of male infertility in the Han-Chinese population. [ABSTRACT FROM AUTHOR]

The complete cytochromeband the control region of mtDNA (about 2070 bp in total) of 10 strains belonging to three subspecies of the common carp, including three wild subspecies (the Yangtze River wild common carp– Cyprinus carpio haematopterus, Yuanjiang River wild common carp– Cyprinus carpio rubrofuscusand Volga River wild common carp– Cyprinus carpio carpio) and seven domestic strains (Xingguo red carp, Russian scattered scaled mirror carp, Qingtian carp, Japanese Koi carp, purse red carp, Big-belly carp, German mirror carp) were sequenced. Phylogenetic analysis indicated that the 10 strains form three distinct clades, corresponding toC. c. haematopterus,C. c. rubrofuscusandC. c. carpiorespectively. Purse red carp, an endemic domestic strain in Jiangxi province of China, showed a higher evolution rate in comparison with the other strains ofC. c. haematopterus, most probably because of intensive selection and a long history of domestication. Base variation ratios among the three subspecies varied from 0.78% (betweenC. c. haematopterusandC. c. rubrofuscus) to 1.47%(betweenC. c. carpioandC. c. rubrofuscus). The topography of the phylogenetic tree and the geographic distribution of three subspecies closely resemble each other. The divergence time betweenC. c. carpioand the other two subspecies was estimated to be about 0.9 Myr and about 0.5 Myr betweenC. c. haematopterusandC. c. rubrofuscus. Based on phylogenetic analysis,C. c. rubrofuscusmight have diverged fromC. c. haematopterus. [ABSTRACT FROM AUTHOR]

Snub-nosed monkeys (Rhinopithecus spp.) are confined to isolated mountainous regions in China and North Vietnam. Their systematic classification and phylogenetic relationship has been controversial. The structures of mitochondrial DNA cytochrome b and 12S rRNA show that the 4 species of Rhinopithecus are quite different from other colobines. It is reasonable to regard them as an independent genus, as determined by external features, morphometric characters and behavior. However, whether or not there should be a subdivision between the Vietnamese and Chinese species at the subgeneric level remains to be clarified; more evidence from a large range of Asian colobine species is needed. The Guizhou species, Rhinopithecus brelichi, is a valid species, which is more closely related to Pygathrix than the other species ( R. roxellana, R. bieti and R. avunculus) are. Results also indicate that 3 species—Rhinopithecus roxellana, R. bieti and R. avunculus—might have diverged from R. brelichi, but the phylogenetic relationship of R. avunculus is not clear. [ABSTRACT FROM AUTHOR]

Nasopharyngeal carcinoma (NPC) is characterized by a high prevalence in Southern China, especially among Cantonese individuals of the Guangdong Province. Epidemiological studies have suggested that frequent exposure to high levels of nitrosamine from preserved foods such as salted fish could be a risk factor for NPC. Cytochrome P450 encompasses a family of enzymes that metabolize carcinogens and CYP2A13, a member of this family, is expressed predominantly in the respiratory tract with the highest levels in the nasal mucosa. In an effort to test whether a correlation exists between CYP2A13 genetic polymorphism and the risk of developing NPC, we sequenced all nine exons and the exon-intron junctions of the CYP2A13 gene in 45 NPC patients. We identified a total of 21 single nucleotide polymorphism (SNPs), including 7 novel SNPs. The most frequent functional variant allele was 74A-1757G-3375T-7233G with a haplotype frequency of 7.8% in the 45 NPC cases. In addition, a stop codon mutation was detected in one case. We then selected the 3 most frequent SNPs and one stop codon mutation to expand our study to a casecontrol analysis within the Cantonese population. A novel haplotype consisting 8 SNPs in introns, and four additional novel SNPs were identified; but no correlation between CYP2A13 genetic polymorphism and individual susceptibility to NPC was observed. [ABSTRACT FROM AUTHOR]