Distribution, seasonal use, and predation of incubation mounds of Orange-footed Scrubfowl on Komodo Island, Indonesia

ABSTRACT.   Megapodes are unique in using only heat from the environment, rather than body heat, to incubate their eggs as well as the precocious independence of their chicks on hatching. Of 22 recognized species of megapodes, 9 are listed as threatened due to factors including habitat loss and fragmentation, and predation on eggs and chicks. Orange-footed Scrubfowl ( Megapodius reinwardt ) are conspicuous components of the Oriental/Austral avifauna that inhabit the monsoon forests of the Lesser Sunda chain of islands in Indonesia. We examined the abundance, patterns of distribution, physical characteristics, seasonal activity, and predation risk of incubation mounds of Orange-footed Scrubfowl on Komodo Island in eastern Indonesia. We surveyed 13 valleys on Komodo Island from April 2002 to January 2005 and located 113 tended and 107 untended incubation mounds. Densities of scrubfowl mounds in our study were similar to that reported by investigators during the 1970s, suggesting little change in the scrubfowl population since then. Most scrubfowl mounds were on sandy or loamy soils in open monsoon forest with little overhead shade, and placement of mounds in such areas may ensure adequate temperatures for egg incubation. Although some mounds were tended during all months, mound use peaked during the late wet season in March. During the dry season (April–November), only a few mounds were tended. Komodo dragons ( Varanus komodoensis ) and wild pigs ( Sus scrofa ) were the primary predators of scrubfowl eggs, with no indication of egg predation by humans. The valley with the largest number of untended mounds in our study also had the largest number of active Komodo dragon nests. This suggests an effect of Komodo dragons on scrubfowl numbers, but additional study is needed.     

Population Dynamics of Bifidobacterium Species in Human Feces during Raffinose Administration Monitored by Fluorescence In Situ Hybridization-Flow Cytometry

The population dynamics of bifidobacteria in human feces during raffinose administration were investigated at the species level by using fluorescence in situ hybridization (FISH) coupled with flow cytometry (FCM) analysis. Although double-staining FISH-FCM using both fluorescein isothiocyanate (FITC) and indodicarbocyanine (Cy5) as labeling dyes for fecal samples has been reported, the analysis was interfered with by strong autofluorescence at the FITC fluorescence region because of the presence of autofluorescence particles/debris in the fecal samples. We circumvented this problem by using only Cy5 fluorescent dye in the FISH-FCM analysis. Thirteen subjects received 2 g of raffinose twice a day for 4 weeks. Fecal samples were collected, and the bifidobacterial populations were monitored using the established FISH-FCM method. The results showed an increase in bifidobacteria from about 12.5% of total bacteria in the prefeeding period to about 28.7 and 37.2% after the 2-week and 4-week feeding periods, respectively. Bifidobacterium adolescentis, the Bifidobacterium catenulatum group, and Bifidobacterium longum were the major species, in that order, at the prefeeding period, and these bacteria were found to increase nearly in parallel during the raffinose administration. During the feeding periods, indigenous bifidobacterial populations became more diverse, such that minor species in human adults, such as Bifidobacterium breve, Bifidobacterium bifidum, Bifidobacterium dentium, and Bifidobacterium angulatum, proliferated. Four weeks after raffinose administration was stopped, the proportion of each major bifidobacterial species, as well as that of total bifidobacteria, returned to approximately the original values for the prefeeding period, whereas that of each minor species appeared to differ considerably from its original value. To the best of our knowledge, these results provide the first clear demonstration of the population dynamics of indigenous bifidobacteria at the species level in response to raffinose administration.     

Cytotoxic chalcones and flavanones from the tree bark of Cryptocarya costata

A new flavanone, 7-hydroxy-5,6-dimethoxyflavanone (1), together with three other flavonoids, didymocarpin (2), 2',4'-dihydroxy-5',6'-dimethoxychalcone (3), and isodidymocarpin (4), had been isolated from the methanol extract of the tree bark of Cryptocarya costata. The structures of these compounds were determined based on spectral evidence, including UV, IR, 1-D and 2-D NMR, and mass spectra. Cytotoxic properties of compounds 1-4 were evaluated against murine leukemia P-388 cells. The chalcones 3 and 4 were found to have substantial cytotoxicity with IC50 of 5.7 and 11.1 microM, respectively.     

Synthesis,Antioxidant Activity,and Structure–Activity Relationship of SCAP1 Analogues

Nine analogues of antioxidant peptide SCAP1 were successfully synthesised using a solid-phase method on a 2-chlorotrytil resin. The compounds were obtained in a range of yields of 7.0–57.8%. The occurrence of aggregation during the synthesis is suspected to be responsible for the poor yields. All peptides were characterized by high-resolution time-of-flight mass spectrometry (HR-TOFMS) and nuclear magnetic resonance (NMR). The antioxidant activities of the SCAP1 analogues as well as SCAP1 were analysed utilising the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assay. The results revealed that all of the analysed peptides exhibited moderate antioxidant properties. Moreover, the evaluation of the structure–activity relationship showed that the Asn residue is an important requirement for the antioxidant activity of SCAP1. The replacement of Asn with other amino acid residues (Thr, Pro, Tyr, Trp and Phe) resulted in a decrease in the IC₅₀ values of the peptides. Notably, however, the replacement of the Lys residue with Val marginally increased the activity.

     

A joint model for longitudinal continuous and time‐to‐event outcomes with direct marginal interpretation

Joint modeling of various longitudinal sequences has received quite a bit of attention in recent times. This paper proposes a so‐called marginalized joint model for longitudinal continuous and repeated time‐to‐event outcomes on the one hand and a marginalized joint model for bivariate repeated time‐to‐event outcomes on the other. The model has several appealing features. It flexibly allows for association among measurements of the same outcome at different occasions as well as among measurements on different outcomes recorded at the same time. The model also accommodates overdispersion. The time‐to‐event outcomes are allowed to be censored. While the model builds upon the generalized linear mixed model framework, it is such that model parameters enjoy a direct marginal interpretation. All of these features have been considered before, but here we bring them together in a unified, flexible framework. The model framework's properties are scrutinized using a simulation study. The models are applied to data from a chronic heart failure study and to a so‐called comet assay, encountered in preclinical research. Almost surprisingly, the models can be fitted relatively easily using standard statistical software.     

Chemotaxis of human blood monocytes toward endothelin-1 and the influence of calcium channel blockers.

The adherence of monocytes to the arterial endothelium followed by its migration into the arterial intima is the earliest event in atherogenesis. The vasoconstrictive peptide, Endothelin-1 (ET-1), is elevated in patients with atherosclerosis. We were interested to know whether ET-1 was a chemoattractant for blood monocytes. Using the modified membrane filter technique for chemotaxsis assessment, ET-1 increased monocyte chemotaxis in a dose-dependent manner. Ca2+ channel blockers, Nifedipine, Diltiazem and Verapamil (5 microM), reduced ET-1 chemotaxsis more than 60% (P < 0.001). Aspirin and Indomethacin (1 mM and 100 microM, respectively) reduced migration by 23% (P < 0.05). Alpha-Lipoic acid, Probucol and Neomycin (100 microM) were also migration inhibitory (37%, P < 0.01). These results suggest that ET-1 is a strong chemoattractant for blood monocytes; Ca2+ influx is probably the major stimulus for the accelerated migration induced by ET-1.     

Novel mutations in <Emphasis Type="Italic">katG</Emphasis> gene of a clinical isolate of isoniazid-resistant <Emphasis Type="Italic">Mycobacterium tuberculosis</Emphasis>

Most of isoniazid-resistant Mycobacterium tuberculosis evolved due to mutation in the katG gene encoding catalase-peroxidase. A set of new mutations, namely T1310C, G1388T, G1481A, T1553C, and A1660G, which correspond to amino acid substitutions of L437P, R463L, G494D, I518T, and K554E, in the katG gene of the L10 clinical isolate M. tuberculosis was identified. The wild-type and mutant KatG proteins were expressed in Escherichia coli BL21(DE3) as a protein of 80 kDa based on sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis. The mutant KatG protein exhibited catalase and peroxidase activities of 4.6% and 24.8% toward its wild type, respectively, and retained 19.4% isoniazid oxidation activity. The structure modelling study revealed that these C-terminal mutations might have induced formation of a new turn, perturbing the active site environment and also generated new intramolecular interactions, which could be unfavourable for the enzyme activities.     

Crude peptones from cowtail ray (Trygon sephen) viscera as microbial growth media

In the processing of cowtail ray (Trygon sephen) in Indonesia, viscera (up to 20% body weight) is wasted together with the head, frame and skin. A series of studies have been carried out to investigate the utilization of the viscera, and the present paper reports the conversion of the viscera into microbiological peptones. Ensilation using 3% (v/w) mixture of propionic and formic acids (1:1, v/v), followed by vacuum evaporation, has been used to prepare crude liquid peptones from cowtail ray viscera. These peptones were compared to three commercial peptones in supporting the growth of microorganisms. Mixed populations of microorganisms from foods (beef, egg and milk) and selected pure microorganisms (Aspergillus flavus, Bacillus subtilis, Saccharomyces cerevisiae, Escherichia coli and Staphylococcus aureus) were grown on liquid media containing 0.5 g test peptones/100 ml and the optical densities were monitored. The biomass produced was measured at the end of incubation period. The results show that crude peptones from cowtail ray viscera performed similar to or even better than commercial peptones as nitrogen sources for microorganisms growth. This revised version was published online in July 2006 with corrections to the Cover Date.     

Phenolic constituents from the wood of Morus australis with cytotoxic activity

A new methylated flavonol, 5,7,2',4'-tetrahydroxy-3-methoxyflavone (1), had been isolated from the methanol extract of the wood of Morus australis, along with nine known compounds, kuwanon C (2), morusin (3), morachalcone A (4), oxyresveratrol (5), 4'-(2-methyl-2-buten-4-yl)oxyresveratrol (6), moracins M (7) and C (8), alboctalol (9), and macrourin B (10). The structures of these compounds were determined based on spectral evidence, including UV, IR, NMR, and mass spectra. Cytotoxic properties of compounds 1-10 were evaluated against murine leukemia P-388 cells. The prenylated stilbene 6 and 2-arylbenzofuran 8, and morusin (3) were found to have strong cytotoxic effects with IC50 values of 6.9, 8.7, and 10.1 microM, respectively.