Female-infant interactions among free-ranging stumptail macaques (Macaca arctoides)

The friendly and aggressive behaviors directed by females other than the mother to the troop's infants were recorded during a six-month long study of stumptail macaques living on an island. A great deal of friendly contacts were directed by the females toward the troop's infants. Juvenile females interacted with infants mainly through social play while adult females directed passive contacts (e.g., touch-hand) to them. While the adult females displayed more care contacts toward male infants the juvenile females preferred the female infants. The social position of the infant's mother in the troop and the attention it received from the males regulated the caring behavior an infant received from the females.     

Xyloside inhibits synthesis of the class II-associated chondroitin sulfate proteoglycan and antigen presentation events

An alternative form of the human invariant chain exists as a chondroitin sulfate proteoglycan (CSPG) with invariant chain as the core protein. The selective inhibitor of proteoglycan synthesis, p-nitrophenyl beta-D-xyloside was used to study the role of this CSPG in class II biology. At xyloside concentrations of 2.5 and 5.0 mM, CSPG synthesis was completely inhibited with marginal inhibition of protein synthesis. The inhibitory effect on CSPG synthesis was completely reversible. The number of class II molecules on the cell surface was not affected by xyloside, but biosynthesis and appearance of newly synthesized class II molecules at the cell surface were both decreased by xyloside. Recognition of influenza virus-infected cells by class II-restricted, virus-specific cytotoxic T lymphocytes was not diminished by the presence of xyloside in the effector phase of the cytotoxicity assay. However, sensitization of target cells was markedly inhibited when target cells were exposed to virus in the presence of xyloside. These results are consistent with the hypothesis that the CSPG form of invariant chain has a role in antigen processing.     

Bat species richness in live fences and in corridors of residual rain forest vegetation at Los Tuxtlas, Mexico

Fragmentation of lowland tropical rain forests has resulted in loss of animal and plant species and isolation of remaining populations that puts them at risk. At Los Tuxtlas. Mexico, lowland rain forests are particularly diverse in the bat fauna they contain and while most of the forests have been fragmented by human activity, many of the fragments still harbor diverse assemblages of bat species. To assess the effectiveness of corridors, among other options, to ameliorate the negative effects of fragmentation, we investigated bat species richness and relative abundance in one 6 km long section of live fences (LF) bordering a dirt road and in three 6 km long sections of residual forest vegetation along the sides of three permanent streams (BS. MS. HS). Netting of bats resulted in the capture of 967 bats. At the LF site we captured 12 bat species. 15 at the BS site. 18 at the MS site and 23 at the HS site. Species richness was associated with average area of forest fragments within a 1000 m band on each side of each corridor (r = 0.97. p = 0.01). Only 28% of the species were common among sites. Frugivorous and insectivorous species accounted for 48% each of bat captures while nectarivores accounted for 3%, sanguinivores for 0.5% and carnivore-frugivores for 0.5% Edge habitat species such as Pteronotus parnelli and Sturnira lilium accounted for 50% of the captiures. Frugivorous species such as Carollia brevicauda. Vampyrodes caraccioli. Dermanura phaeotis, D. toltecus and A. jamaicensis accounted for another 25% of bat captures. Recaptures of bats indicated bat movements from forest fragments to corridors and between corridors, with recapture distances ranging from 200 to 2000 m. Within corridor recaptures separated by several months from the original recapture date indicated individual bat revisitation to these sites. We discuss the value of these corridors to bats as stepping stones in the fragmented landscape.     

Comparable Ascertainment of Newly-Diagnosed Atrial Fibrillation Using Active Cohort Follow-Up versus Surveillance of Centers for Medicare and Medicaid Services in the Atherosclerosis Risk in Communities Study

Objective

Increasingly, epidemiologic studies use administrative data to identify atrial fibrillation (AF). Capture of incident AF is not well documented. We examined incidence rates and concordance of AF diagnosis based on active cohort follow-up versus surveillance of Centers for Medicare and Medicaid Services data in the Atherosclerosis Risk in Communities study.

Methods

Atherosclerosis Risk in Communities cohort participants without prevalent AF enrolled in fee-for-service Medicare, with inpatient and outpatient coverage, for at least 12 continuous months between 1991 and 2009 were included. In active Atherosclerosis Risk in Communities study follow-up, annual telephone calls captured hospitalizations and deaths with incident AF diagnosis codes. For Centers for Medicare and Medicaid Services data, incident AF was defined by billed inpatient and outpatient diagnoses.

Results

Of 10,134 eligible cohort participants, 738 developed AF according to both Atherosclerosis Risk in Communities and Centers for Medicare and Medicaid Services data; an additional 93 and 288 incident cases were identified using only Atherosclerosis Risk in Communities and Centers for Medicare and Medicaid Services data, respectively. Incidence rates per 1,000 person-years were 10.8 (95% confidence interval: 10.1–11.6) and 13.6 (95% confidence interval: 12.8–14.4) in Atherosclerosis Risk in Communities and Centers for Medicare and Medicaid Services, respectively; agreement was 96%; kappa was 0.77 (95% confidence interval: 0.75–0.80). Earlier AF ascertainment by one system versus the other was not associated with any cardiovascular disease risk factors, after accounting for sociodemographic factors. Additional Centers for Medicare and Medicaid Services events did not alter observed associations between risk factors and AF.

Conclusion

Among fee-for-service enrollees, AF incidence rates were slightly lower for active cohort follow-up than for Centers for Medicare and Medicaid Services surveillance, because the latter included outpatient atrial fibrillation. Concordance was high and combining the two approaches could provide a more complete picture of newly-diagnosed AF.     

Identification and functional characterization of <Emphasis Type="Italic">Candida albicans CDC4</Emphasis>

Summary The CDC4 gene of Saccharomyces cerevisiae encodes an essential function that is required for G1-S and G2-M transitions during mitosis and at various stages during meiosis. We have isolated a functional homologue of CDC4 (CaCDC4) from the pathogenic yeast Candida albicans by complementing the S. cerevisiae cdc4-3 mutation with CaCDC4 expressed from its own promoter on a single-copy vector. The predicted product of CaCDC4 has 37% overall identity to the S. cerevisiae Cdc4 protein, although this identity is biased towards the C-terminal region of the two proteins which contains eight copies of the degenerate WD-40 motif, an element found in proteins that regulate diverse biological processes and an F-box domain proximal to the first iteration of the WD-40 motif. Both the F-box domain and WD-40 motifs appear necessary for the mitotic functions of Cdc4 in both yeasts. In contrast to its conserved role in mitosis, C. albicans CDC4 is unable to rescue the meiotic deficiency in a S. cerevisiae cdc4 homozygous diploid under restrictive conditions, even when expressed from an efficient S. cerevisiae promoter. In opposition to S. cerevisiae CDC4 being essential, C. albicans CDC4 appears to be nonessential and in its absence is critical for filamentous growth in C. albicans.