The Complete Chloroplast Genome of An Ophiorrhiza baviensis Drake Species Reveals Its Molecular Structure, Comparative, and Phylogenetic Relationships

Ophiorrhiza baviensis Drake, a flowering medical plant in the Rubiaceae, exists uncertainly within the Ophiorrhiza genus' evolutionary relationships. For the first time, the whole chloroplast (cp) genome of an O. baviensis Drake species was sequenced and annotated. Our findings demonstrate that the complete cp genome of O. baviensis is 154,770 bp in size, encoding a total of 128 genes, including 87 protein-coding genes, 8 rRNAs, and 33 tRNAs. A total of 59 SSRs were screened in the studied cp genome, along with six highly variable loci, which can be applied to generate significant molecular markers for the Ophiorrhiza genus. The comparative analysis of the O. baviensis cp genome with two published others of the Ophiorrhiza genus revealed a high similarity; however, there were some notable gene rearrangements in the O. densa plastome. The maximum likelihood phylogenetic trees were constructed based on the concatenation of the rps16 gene and the trnL-trnF intergenic spacer sequence, indicating a close relationship between the studied O. baviensis and other Ophiorrhiza. This study will provide a theoretical molecular basis for identifying O. baviensis Drake, as well as species of the Ophiorrhiza genus, and contribute to shedding light on the chloroplast genome evolution of Rubiaceae.

Genetic diversity of Vietnamese domestic chicken populations as decision-making support for conservation strategies

The aims of this study were to assess the genetic diversity of 17 populations of Vietnamese local chickens (VNN) and one Red Jungle Fowl population, together with six chicken populations of Chinese origin (CNO), and to provide priorities supporting the conservation of genetic resources using 20 microsatellites. Consequently, the VNN populations exhibited a higher diversity than did CNO populations in terms of number of alleles but showed a slightly lower observed heterozygosity. The VNN populations showed in total seven private alleles, whereas no CNO private alleles were found. The expected heterozygosity of 0.576 in the VNN populations was higher than the observed heterozygosity of 0.490, leading to heterozygote deficiency within populations. This issue could be partly explained by the Wahlund effect due to fragmentation of several populations between chicken flocks. Molecular analysis of variance showed that most of genetic variation was found within VNN populations. The Bayesian clustering analysis showed that VNN and CNO chickens were separated into two distinct groups with little evidence for gene flow between them. Among the 24 populations, 13 were successfully assigned to their own cluster, whereas the structuring was not clear for the remaining 11 chicken populations. The contributions of 24 populations to the total genetic diversity were mostly consistent across two approaches, taking into account the within- and between-populations genetic diversity and allelic richness. The black H'mong, Lien Minh, Luong Phuong and Red Jungle Fowl were ranked with the highest priorities for conservation according to Caballero and Toro's and Petit's approaches. In conclusion, a national strategy needs to be set up for Vietnamese chicken populations, with three main components: conservation of high-priority breeds, within-breed management with animal exchanges between flocks to avoid Wahlund effect and monitoring of inbreeding rate.

Bloodstream infection associated with needleless device use and the importance of infection-control practices in the home health care setting

The influence of infection-control practices on bloodstream infection (BSI) risk was examined in a home health care setting in which three needleless devices were used consecutively. A case-control study and a retrospective cohort study were conducted. Risk factors for BSI included lower education level, younger age, having a central venous catheter (CVC) with multiple ports, or having a tunneled CVC. Among patients with a tunneled CVC, those at greatest risk had been allowed to shower rather than bathe and to get their exit site wet (P<.01). A high proportion (49%) of isolates were hydrophilic gram-negative bacteria, suggesting water sources of infection. In the cohort study, the BSI rate decreased as the frequency of changing the needleless device end cap increased from once weekly up to every 2 days, suggesting that the mechanism for BSI may involve contamination from the end cap. These findings may help to develop infection-control measures specific to home health care.

Artificial transposable elements in the study of the ends of IS1

We have constructed artificial IS1-based transposons by attaching synthetic oligodeoxynucleotides, corresponding to the sequence of the ends of IS1, to a selectable DNA segment ['omega' fragment; Prentki and Krisch, Gene 29 (1984) 303-313]. These transposons were used to examine the sequence requirements at the ends for IS1 transposition. We show here that a 24- to 28-bp sequence from the left or right ends of IS1 is capable of transposition when present at both ends of the omega fragment in the correct orientation. Transposition activity requires the presence of an intact IS1 in cis on the same plasmid molecule. In trans, however, neither resident genomic copies of IS1, nor copies carried by a compatible, high-copy-number plasmid present in the same cell, complement the artificial transposons efficiently. Transposition frequencies in the presence of a cis-complementing IS1 are, however, similar to those of the naturally occurring IS1-based transposon, Tn9. In addition, transposition results in a 9-bp duplication in the target DNA molecule as is usually the case for insertion of the intact IS1. Using this system, we have obtained evidence indicating that the activity of a synthetic IS1 end is not determined exclusively by its sequence, but can be strongly enhanced by a second, wild-type end used in the transposition event. The data also show that single base pair mutations can exhibit a cumulative effect in reducing transposition activity.

Rosette-forming cells in patients with treated leprosy

White blood cell counts and the percentages and absolute numbers of lymphocytes in the peripheral blood of active lepromatous (BT, BB, BL) leprosy patients, patients with borderline leprosy, and normal controls were determined. Lepromatous patients showed decreased leukocyte counts and elevated percentages of lymphocytes, resulting in normal absolute lymphocyte counts. The proportion of peripheral blood mononuclear cells forming "active" rosettes, standard (4 degrees C overnight) rosettes, and "high affinity" (29 degrees C for 1 hr) rosettes with sheep erythrocytes, and rosettes with EAC were determined. Lepromatous patients, compared with normal controls, had decreased "active" rosettes, standard rosettes, and "high affinity" rosettes with sheep erythrocytes with an increase in the nonrosetting proportion. Both lepromatous and borderline leprosy patients showed increased percentages of EAC rosettes compared with normal controls.