MULTIPLE GENOTYPES OF MITOCHONDRIAL-DNA WITHIN A HORSE POPULATION FROM A SMALL REGION IN YUNNAN PROVINCE OF CHINA

mtDNA genotypes of six domestic horses (three adult short horses whose heights are under 1 m and three common domestic horses) from a small region of 15 km(2) in Malipo county of Yunnan province of China were investigated by the technique of restriction fragment length polymorphism (RFLP) with restriction endonucleases which recognize 6-bp sequences. An average of fragments for an individual was obtained. Unlike other domestic animals, this population of horses exhibits high mtDNA genetic diversity. Each of the six horses has a specific mtDNA genotype showing a pattern of multiple maternal origins, as suggested by fossil and literature records. We think the population of horses is an amazing seed-resource pool of horses and hence deserves to be paid more attention from the view of conservation genetics. However it is also remarkable that we did not find any typical mtDNA genetic markers which would discriminate between short horses and common domestic horses.

On-going generation of multiple forms of HIV-1 intersubtype recombinants in the Yunnan Province of China

Objectives: To investigate the molecular epidemiology of HIV in China's Yunnan Province, where the initial HIV-1 outbreak among injecting drug users (IDU) occurred in 1989, and to analyse the genesis and interrelationship of the epidemic with that in surrounding areas. Design: A molecular epidemiological investigation was conducted among IDU in three prefectures in Yunnan Province, including Wenshan (east), Honghe (southeast) and Dehong (west). Methods: Thirty-nine specimens were collected from consenting IDU in 2000-2001. The nucleotide sequences of 2.6 kb gag-RT and 340 base pair (bp) env (C2/V3) regions were determined. Phylogenetic tree and recombination breakpoint analyses were performed. Results: The circulating recombinant form (CRF), CRF08_BC, predominated in east Yunnan near Guangxi Province (89% in Wenshan and 81% in Honghe), whereas it was not detected in Dehong(0/14) in the west. In contrast, 71% (10/14) of the Dehong isolates were unique recombinant forms (URF), mostly between subtypes B' (Thailand variant of subtype B) and C, with distinct profiles of recombination breakpoints. The subtype B' accounts for the remaining 29% (4/14) of Dehong isolates. Interestingly, two Honghe isolates (2/16) shared some of the precise B'/C recombination breakpoints with CRF07_BC. Conclusion: New recombinant strains are arising continually in west Yunnan near the Myanmar border. Some appeared to be secondary recombinants derived from CRF07_BC that had further recombined with other strains. The uneven distribution of subtypes, CRF and URF, suggests the presence of independent transmission networks and clusters among IDU in Yunnan. (C) 2002 Lippincott Williams Wilkins.

Molecular epidemiology of the heterosexual HIV-1 transmission in Kunming, Yunnan Province of China suggests origin from the local IDU epidemic

Molecular epidemiological investigation was conducted among injecting drug users (IDUs) (n = 11) and heterosexuals (n = 15) in Kunming, Yunnan Province of China. HIV-1 genotypes were determined based on the nucleotide sequences of 2.6-kb gag-RT region. The distribution of genotypes among IDUs was as follows: CRF07_BC (5/11) and CRF08_BC (5/11); subtype B' (1/11). Similarly, a majority of Kunming heterosexuals (14/15) were infected with CRF07_BC (4/15), CRF08_BC (6/15), or subtype B' (4/15), known to predominate among IDUs in China. This contrasts with trends in the coastal regions of China and surrounding southeastern Asian countries, where CRF01_AE predominates among heterosexuals. The heterosexual HIV-1 epidemic in Kunming thus appears to derive from the local IDU epidemic. Of note, subtype B' was the most prevalent strain among heterosexuals before 1997, while CRF07_BC and CRF08_BC became predominant in 2002, indicating a transition of HIV-1 genotype distribution between the early and the more recent samples from Kunming heterosexuals.

Analysis of arable land loss and its impact on rural sustainability in Southern Jiangsu Province of China

Rapid urbanization and industrialization in southern Jiangsu Province have consumed a huge amount of arable land. Through comparative analysis of land cover maps derived from TM images in 1990, 2000 and 2006, we identified the trend of arable land loss. It is found that most arable land is lost to urbanization and rural settlements development. Urban settlements, rural settlements, and industrial park-mine-transport land increased, respectively, by 87 997 ha (174.65%), 81 041 ha (104.52%), and 12 692 ha (397.99%) from 1990 to 2006. Most of the source (e.g., change from) land covers are rice paddy fields and dryland. These two covers contributed to newly urbanized areas by 37.12% and 73.52% during 1990-2000, and 46.39% and 38.86% during 2000-2006. However, the loss of arable land is weakly correlated with ecological service value, per capita net income of farmers, but positively with grain yield for some counties. Most areas in the study site have a low arable land depletion rate and a high potential for sustainable development. More attention should be directed at those counties that have a high depletion rate but a low potential for sustainable development. Rural settlements should be controlled and rationalized through legislative measures to achieve harmonious development between urban and rural areas, and sustainable development for rural areas with a minimal impact on the ecoenvironment. (C) 2009 Elsevier Ltd. All rights reserved.

Sediment provenance and province of the southern Yellow Sea: Evidence from light mineral

The distribution for percent content of light mineral is divided in detail to emphasize distributional trends of higher and lower contents by using 222 samples of light mineral in the southern Yellow Sea. 5 mineral provinces are divided, and they are I-north mineral province of the southern Yellow Sea, the sediment dominantly derived from the Yellow River; II-mixed mineral province, the sediment derived from both the Yellow River and Yangtze River; III-middle mineral province, the sediment derived mainly from the Yellow River and a part of sediment derived from Yangtze River; IV-province east of Yangtze River mouth, the sediment derived dominantly from Yangtze River; and V south mineral province, sediment was affected by relict sediment and modern sediment of Yangtze River. In this paper, the assemblage of dominant mineral and diagnostic mineral for the five provinces are discerned.

A preliminary discussion on the bio-metallogenesis of Tl deposits in the low-temperature minerogenetic province of southwestern China

Starting with the research status of bio-metallogenesis of Tl deposits and their geology, this work deals with the geological background of Tl enrichment and mineralization and the mechanism of bio- metal-logenesis of Tl deposits, as exemplified by Tl deposits in the low-temperature minerogenetic province. This research on the bio-metallogenesis of Tl deposits is focused on the correlations between bio-enrichment and Tl, the enrichment of Tl in micro-paleo-animals in rocks and ores, bio-fossil casts in Tl-rich ores, the involvement of bio-sulfur in minerogenesis and the enrichment of bio-genetic organic carbon in Tl ores. Thallium deposits have experienced two ore-forming stages: syngenetic bio- en-richment and epigenetic hydrothermal reworking (or transformation). Owing to the intense epigenetic hydrothermal reworking, almost no bio-residues remain in syngenetically bio-enriched Tl ores, thereby the Tl deposits display the characteristics of hydrothermally reoworked deposits.

Bibarba bibarba: A new genus and species of Cobitinae (Pisces : Cypriniformes : Cobitidae) from Guangxi Province (China)

A new genus of Cobitinae, Bibarba gen. n., and a new species, B. bibarba sp. n., were discovered and are described for the Chengjiang River, a tributary of the Hongshuihe River in Guangxi Province of southern China. This river region is characterized by a Karst landscape, and the river that is inhabited by the new genus is a slowly moving stream with arenaceous and cobblestone beds. The new genus resembles Cobitis Linnaeus, 1758 (subfamily Cobitinae) in the shape and pigmentation pattern of their body, the absence of scales on their head, and the presence of a suborbital spine, but differs from it by a single Lamina circularis on the third pectoral fin ray instead of on the base of the second pectoral fin ray; two pairs of barbels (one rostral pair and one maxillo-mandibular pair) instead of three pairs of barbels (one rostral pair, one maxillary pair, and one maxillo-mandibular pair); a relatively thick and short suborbital spine with a strong medio-lateral process instead of a suborbital spine without or with a weakly formed medio-lateral process as in Cobitis; and the lack of a black stripe extending from the occiput through the eye to the insertion of the rostral barbel. The first two characters have not been reported in any other genus of the subfamily Cobitinae. A morphometric character analysis based on PCA reveals differences between B. bibarba and C. sinensis in body size, barbel length, interorbital width, pectoral fin length in males, and the position of the dorsal and ventral fins. Type specimens of the new species are kept in the Freshwater Fishes Museum of the Institute of Hydrobiology at the Chinese Academy of Sciences in Wuhan, Hubei Province. (c) 2007 Elsevier GmbH. All rights reserved.

Preparation, characterization and gas sensing properties of nickel octa-iso-pentyloxynaphthalocyanine spin-coating films

Spin-coated films of nickel 1,6,10,15,19,24,28,33-octa-iso-pentyloxy-2,3-naphthalocyanine complex were obtained and characterized by UV-vis absorption spectroscopy. A linear relationship between the absorbance and solution concentration was observed. Low concentration solutions could afford smooth and homogeneous film surfaces as indicated by atomic force microscopy. The film structure was studied by small angle X-ray diffraction. The films were used for NO2 sensing experiments. The results indicate that the elevation of sensing temperature can shorten the response time and increase recovery ratio and response magnitude of the sensing films. High NO2 concentration can also shorten response time. (C) 2008 Elsevier B.V. All rights reserved.

Characterization and Comparison of the Tissue-Related Modules in Human and Mouse

Background: Due to the advances of high throughput technology and data-collection approaches, we are now in an unprecedented position to understand the evolution of organisms. Great efforts have characterized many individual genes responsible for the interspecies divergence, yet little is known about the genome-wide divergence at a higher level. Modules, serving as the building blocks and operational units of biological systems, provide more information than individual genes. Hence, the comparative analysis between species at the module level would shed more light on the mechanisms underlying the evolution of organisms than the traditional comparative genomics approaches. Results: We systematically identified the tissue-related modules using the iterative signature algorithm (ISA), and we detected 52 and 65 modules in the human and mouse genomes, respectively. The gene expression patterns indicate that all of these predicted modules have a high possibility of serving as real biological modules. In addition, we defined a novel quantity, "total constraint intensity,'' a proxy of multiple constraints (of co-regulated genes and tissues where the co-regulation occurs) on the evolution of genes in module context. We demonstrate that the evolutionary rate of a gene is negatively correlated with its total constraint intensity. Furthermore, there are modules coding the same essential biological processes, while their gene contents have diverged extensively between human and mouse. Conclusions: Our results suggest that unlike the composition of module, which exhibits a great difference between human and mouse, the functional organization of the corresponding modules may evolve in a more conservative manner. Most importantly, our findings imply that similar biological processes can be carried out by different sets of genes from human and mouse, therefore, the functional data of individual genes from mouse may not apply to human in certain occasions.

Genetic diversity and relationship of Yunnan native cattle breeds and introduced beef cattle breeds

In this study, random amplified polymorphic DNA (RAPD) analysis was used to estimate genetic diversity and relationship in 134 samples belonging to two native cattle breeds from the Yunnan province of China (DeHong cattle and DiQing cattle) and four intro

DEVELOPMENT OF MICROSATELLITE LOCI FOR PINUS KORAIENSIS (PINACEAE)

Premise of the study: Microsatellite markers were developed for Pinus koraiensis to characterize its genetic diversity and understand its population structure. Methods and Results: Using the Fast Isolation by AFLP of Sequences COntaining (FIASCO) Repeats protocol, 20 primer sets were developed in Chinese populations of P. koraiensis. Three of the markers showed polymorphism with two alleles per locus when assessed in a sample of two populations of P. koraiensis from the Changbai Mountain in the Jilin Province of China. Five and three loci were successfully amplified in P. taiwanensis and P. massoniana, respectively. The amplification size of these loci matches those in P. koraiensis. Conclusions: These markers may be useful for further investigation of population genetics of P. koraiensis.

Threatened fishes of the world: Plesiomyzon baotingensis (Zheng & Chen, 1980) (Cypriniformes: Balitoridae)

We are grateful to all the voluntary donors of DNA samples in this study. We thank Hui Zhang and Yan-jiao Li for their technical help. We also thank Dr. Darren Curnoe for his critical reading of the manuscript. This study was supported by grants from the National 973 project of China (2007CB947701,2007CB815705), the Chinese Academy of Sciences (KSCX1YW-R-34, Westlight Doctoral Program), the National Natural Science Foundation of China (30525028, 30700445, 30630013 and 30771181), and the Natural Science Foundation of Yunnan Province of China (2007C100M, 2009CD107).

In vitro activities of small peptides from snake venom against clinical isolates of drug-resistant Mycobacterium tuberculosis

The recent re-emergence of tuberculosis, especially the multidrug-resistant cases, has highlighted the importance of screening effective novel drugs against Mycobacterium tuberculosis. In this study, the in vitro activities of small peptides isolated from snake venom were investigated against multidrug-resistant M. tuberculosis. Minimum inhibitory concentrations (MICs) were determined by the Bactec TB-460 radiometric method. A small peptide with the amino acid sequence ECYRKSDIVTCEPWQKFCYREVTFFPNHPVYLSGCASECTETNSKWCCTTDKCNRARGG (designated as vgf-1) from Naja atra (isolated from Yunnan province of China) venom had in vitro activity against clinically isolated multidrug-resistant strains of M. tuberculosis. The MIC was 8.5 mg/l. The antimycobacterial domain of this 60aa peptide is under investigation. (C) 2003 Elsevier Science B.V. and the International Society of Chemotherapy. All rights reserved.