SOCIAL-DEVELOPMENT OF INFANTS OF MACACA-THIBETANA AT MOUNT-EMEI, CHINA

The development of infant Macaca thibetana was studied at Mount Emei, China, and compared to that of other macaque species. It was found that there are many common features in the process of infant socialization in species of the genus Macaca: mothers play an important and active role, other group members influence the infants' development to a greater or lesser extent and play is a major activity in the life of infants. Some differences were found to exist, however, between macaque species. These included differences in maternal care behaviour such as 'len', leaving time and weaning time. Paternal behaviours were also found to vary within and among species. Tibetan macaque males care for infants extensively, and they may use infants as an agonistic buffer. The natural and social environment may also influence differences between macaque species in infant development.

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.

Social organization of black-and-white snub-nosed monkeys (Rhinopithecus bieti) at Deqin, China

Data on social organization of two bands of black-and-white snub-nosed monkeys (Rhinopithecus bieti) 14 were collected when the monkeys were crossing an open spot at Nanren and Bamei (northwest of Yunnan, China) using a sampling rule where individuals wit

Physiological comparison between colonial and unicellular forms of Microcystis aeruginosa Kutz. (Cyanobacteria)

In order to gain insight into the bloom sustainment of colonial Microcystis aeruginosa Katz., physiological characterizations were undertaken in this study. Compared with unicellular Microcystis, colonial Microcystis phenotypes exhibited a higher maximum photosynthetic rate (Pm), a higher maximum electron transfer rate (ETRmax), higher phycocyanin content, and a higher affinity for inorganic carbon (K-0.5 DIC <= 8.4 +/- 0.7 mu M) during the growth period monitored in this study. This suggests that photosynthetic efficiency is a dominant physiological adaptation found in colonial Microcystis, thus promoting bloom sustainment. In addition, the high content of soluble and total carbohydrates in colonial Microcystis suggests that this phenotype may possess a higher ability to tolerate enhanced stress conditions when compared to unicellular (noncolonial) phenotypes. Therefore, high photosynthetic activities and high tolerance abilities may explain the bloom sustainment of colonial Microcystis in eutrophic lakes.

Ultrastructure of the bloodstream forms of the fish trypanosome Trypanosoma pseudobagri dogiel et achmerov, 1959

The ultrastructure of the bloodstream forms of Trypanosoma pseudobagri from its natural host, yellow catfish (Pseudobagrus fulvidraco), a freshwater fish, is described in the present work. The pellicle, consisting of a unit membrane with a superimposed surface coat, the structure and attachment of the flagellum and the subpellicular microtubules show the usual structural and organizational features. Cell organelles and cytoplasmic inclusions such as kinetoplast, mitochondria, nucleus and vacuoles, which occur in trypanosomidae, are observed and described in detail. The ultrastructure of T. pseudobagri has been compared with that of bloodstream forms of other species and culture forms of fish trypanosomes, and similarities and divergences are discussed. The Golgi-complex and endoplasmic reticulum could not be observed and need further investigation.

Molecular cloning of growth hormone receptor (GHR) from common carp (Cyprinus carpio L.) and identification of its two forms of mRNA transcripts

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2-year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1806 nucleotides is translated into a putative peptide of 602 amino acids, including an extracellular ligand-binding domain of 244 amino acids (aa), a single transmembrane domain of 24 aa and an intracellular signal-transduction domain of 334 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2-year common carp, a 224 bp product was identified in liver and a 321 bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 321 bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2-year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2-year common carp was significantly tower than that of 4-month common carp.

Genetic heterogeneity analysis and RAPD marker detection among four forms of Atrina pectinata Linnaeus

Pen shell (Atrina pectinata Linnaeus) can be distinguished into four forms based on the morphololgic characteristics. Genetic similarity, and heterogeneity were analyzed among the four forms by random amplified polymorphic DNA (RAPD) technique using 24 10-nucleotide-long primers. Of these primers, 22 pruners produced well-identifiable RAPD band patterns. Significant differences in RAPD band patterns were revealed among the four forms. A total of 198 polymorphic fragments were scored from 22 pruners. and they are specific for one form, shared by two or three forms. Several pruners, such as S451, S453 S463 S464, S470. S473 and S474, produced abundant band patterns and provided sufficient information for reliable discrimination of the four forms. The average genetic distances and phylogenetic relationships were calculated and analyzed according to the distinguishable fragments. The data indicate that pen shells of form G and form Y are similar not only among individuals within the same form, but also between individuals from the two forms, and that shells of form T and form S are highly divergent. The constructed phylogenetic free matches the average genetic distances. Three clusters were clearly distinguishable, in which two were corresponding to form S and form T respectively and one included forms G and Y. This Study will be benefit to further studies oil the taxonomy and selective breeding of Pinnid species. It is suggested that the four forms of pen shell should be categorized to at least two species taxonomically.