Displaying publications 241 - 260 of 1650 in total

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  1. Relationship between rainfall and Aedes larval population at two insular sites in Pulau Ketam, Selangor, Malaysia
    Wee LK, Weng SN, Raduan N, Wah SK, Ming WH, Shi CH, et al.
    Southeast Asian J Trop Med Public Health, 2013 Mar;44(2):157-66.
    PMID: 23691624
    Two insular settlements (Kampung Pulau Ketam and Kampung Sungai Lima) were selected to study the population dynamics of Aedes aegypti and Aedes albopictus mosquitoes, vectors of dengue and chikungunya infections. Ovitrap surveillance was conducted between October 2007 and October 2008. There was an inverse negative association between ovitrap index and rainfall at the time of collection, probably because rainfall increased the number of available oviposition sites. Rainfall and ovitrap index were positively associates the 25th day after rainfall occurred. A minor, second peak was observed from the 38th to the 42nd day. The first peak was consistent with the minimum 18-day period between the hatching of eggs to the first oviposition. The second minor peak could be due to the second gonotrophic cycle of the female mosquitoes. Rainfall is an important environmental factor associated with Aedes breeding at the study sites.
    Matched MeSH terms: Aedes/growth & development*; Insect Vectors/growth & development*; Larva/growth & development
  2. A New Species of Simulium (Gomphostilbia) (Diptera: Simuliidae) From Kalimantan, Indonesia, With Keys to Identify 19 Bornean Species of the Subgenus Gomphostilbia
    Takaoka H, Sofian-Azirun M, Ya'cob Z, Chen CD, Low VL, Harmonis
    J Med Entomol, 2016 07;53(4):798-806.
    PMID: 27099400
    A new simuliid species, Simulium kalimantanense sp. nov., is described on the basis of females, males, pupae, and mature larvae from East Kalimantan, Indonesia, and is assigned to the Simulium banauense species-group of Simulium (Gomphostilbia). This new species has close similarities to S alienigenum Takaoka from the Philippines, in many characters including the adult antennal color pattern and pupal gill with four long filaments arranged in two pairs each bearing a long stalk, but is distinguished from the latter in the female by the longer sensory vesicle and in the pupa by the gill with an elongate common basal stalk. Simulium kalimantanense sp. nov. is the first member of the S. banauense group in Borneo, and marks the most southerly distribution of the group. Keys to identify 19 Bornean species of the subgenus Gomphostilbia are provided.
    Matched MeSH terms: Larva/growth & development; Pupa/growth & development; Simuliidae/growth & development
  3. Fulltext Distribution pattern of black fly (Diptera: Simuliidae) assemblages along an altitudinal gradient in Peninsular Malaysia
    Ya'cob Z, Takaoka H, Pramual P, Low VL, Sofian-Azirun M
    Parasit Vectors, 2016 Apr 19;9:219.
    PMID: 27094088 DOI: 10.1186/s13071-016-1492-7
    BACKGROUND: Preimaginal black flies (Diptera: Simuliidae) are important components of the stream ecosystem. However, there has been limited research undertaken on the vertical distribution of preimaginal black flies and their associated ecological factors. Stream conditions are generally variable along the altitudinal gradient. Therefore, we conducted an in-depth entomological survey to investigate the simuliid distribution pattern along an altitudinal gradient in Peninsular Malaysia.

    METHODS: A total of 432 collections were performed in this study (24 samplings at each of 18 fixed-streams at monthly intervals) from February 2012 to January 2014. Larvae and pupae attached on aquatic substrates such as grasses, leaves and stems, twigs, plant roots and rocks were collected by hand using fine forceps. Stream depth (m), width (m), velocity (m/s), water temperature (°C), acidity (pH), conductivity (mS/cm) and dissolved oxygen (mg/L) were measured at the time of each collection.

    RESULTS: A total of 35 black fly species were recorded in the present study. The most frequently collected species were Simulium tani (31.7%) and S. whartoni (21.5%), while the relatively common species were Simulium sp. (nr. feuerborni) (16.2%), S. decuplum (15.5%), S. angulistylum (14.8%), S. bishopi (13.2%) and S. izuae (11.8%). Total estimated species richness ranged between 39.8 and 41.3, which yielded more than 80% of sampling efficiency. Six simuliid species were distributed below 500 m, whereas eight species were distributed above 1400 m. Simulium sp. (nr. feuerborni) and S. asakoae were found from middle to high altitudes (711-1813 m). Simulium whartoni, S. brevipar and S. bishopi were distributed widely from low to high altitudes (159-1813 m). Regression analysis between species richness and PCs revealed that the species richness was significantly associated with wider, deeper and faster streams at low altitude, normal water temperature (23-25 °C), low conductivity, higher discharge, more canopy cover and riparian vegetation and with larger streambed particles (F = 20.8, df = 1, 422, P 

    Matched MeSH terms: Larva/growth & development; Pupa/growth & development; Simuliidae/growth & development
  4. ABSENCE OF AEDES AEGYPTI (L.) ON AN ECOLOGICAL ISLAND: COMPETITIVE EXCLUSION?
    Afizah AN, Mahirah MN, Azahari AH, Asuad MK, Nazni WA, Lee HL
    Southeast Asian J Trop Med Public Health, 2015 Sep;46(5):850-6.
    PMID: 26863856
    Ovitrap surveillance was conducted in 2012 and 2006 in Malay and Aboriginal Villages on Carey Island. In each village, standard ovitraps were placed indoors and outdoors at randomly selected houses/locations. All L3 larvae recovered were identified up to species level. Results demonstrated that only larvae of Aedes albopictus were found in all the positive ovitraps placed indoors and outdoors. In 2012, a high ovitrap index (OI) of 66.7% indoor and 84.0% outdoor in the Malay Village; and 62.5% indoor and 88.0% outdoor in Aboriginal Village with an apparent absence of Aedes aegypti. In 2006, a 100% OI was recorded in all ovitraps set indoors and outdoors in both villages.
    Matched MeSH terms: Aedes/growth & development; Insect Vectors/growth & development; Larva/growth & development
  5. Two new Species of Simulium (Simulium) (Diptera: Simuliidae) From Mount Murud, Sarawak, Malaysia
    Takaoka H, Ya'cob Z, Sofian-Azirun M
    J Med Entomol, 2015 Jan;52(1):38-49.
    PMID: 26336278 DOI: 10.1093/jme/tju009
    Two new species of black flies, Simulium (Simulium) murudense and Simulium (Simulium) cheedhangi, are described on the basis of females, males, pupae, and larvae collected in Mount Murud, Sarawak, Malaysia. Both species belong to the Simulium melanopus Edwards species group. S. (S.) murudense sp. nov. is distinguished from most known species by a combination of the haired basal portion of the radial vein and the darkened fore coxae, and S. (S.) cheedhangi sp. nov. is characterized in the female by having a medium-sized claw tooth and in the pupa by six somewhat inflated gill filaments. Notes are given on the S. melanopus species-group in Sarawak and Sabah.
    Matched MeSH terms: Larva/growth & development; Pupa/growth & development; Simuliidae/growth & development
  6. A preliminary study on the effects of substituting fishmeal with defatted black soldier fly (Hermetia illucens) larval meal on Asian seabass (Lates calcarifer) juveniles: Growth performance, feed efficiency, nutrient composition, disease resistance, and economic returns
    Liu Y, Andin VC, Chor WK, Gunasekaran B, Chong CM, Lee PT, et al.
    J Fish Biol, 2024 Dec;105(6):1681-1693.
    PMID: 39175254 DOI: 10.1111/jfb.15908
    This study aims to develop an alternative aquafeed derived from insect meal for Lates calcarifer juveniles, with the objectives of exploring the physiological performance, biological parameters, and economic analysis of substituting fishmeal (FM) with defatted black soldier fly (Hermetia illucens) larvae (BSFL) as part of the diet of L. calcarifer juveniles. Five practical diets were formulated to include 0% (BSFL0, serves as control group), 5% (BSFL5), 10% (BSFL10), 15% (BSFL15), and 20% (BSFL20) of BSFL meal, partially or fully replacing FM, respectively. Each diet was randomly assigned to triplicate groups of 30 fish (10.70 ± 0.07 g) per tank (300 L). The fish were fed twice daily to apparent satiation. A 56-day feeding trial was conducted to evaluate the impacts of defatted BSFL meal replacing FM on the growth performance, feed efficiency, composition analysis of fish muscle, cumulative mortality rate challenged with Vibrio parahaemolyticus, and economic returns of L. calcarifer. These results show that differences in weight gain and specific growth rate among the different treatments were statistically significant (p  BSFL0 > BSFL5 > BSFL15 > BSFL20. However, the feed conversion ratio and protein efficiency ratio showed the opposite trend as above. Although the diets experienced a decline in crude protein content and an increase in crude fat content with the increasing proportion of BSFL substituting FM, the crude protein and fat content of fish muscle were only slightly influenced. It is worth mentioning that levels of nonessential amino acids, delicious amino acids, saturated fatty acids, omega-6, omega-9 in BSFL10 group all showed an increase compared with the control group. After a 7-day challenge test with V. parahaemolyticus, the cumulative mortality rates of the BSFL5 and BSFL10 groups, respectively, dropped to 5.20%, 5.28% compared to the control group's 16.88%; however, the mortality rates of BSFL15 (34.67%) and BSFL20 (41.77%) groups were found to be significantly (p 15%) leads to a negative effect. From an economic point of view, 10% inclusion of BSFL in practical diets is recommended for L. calcarifer juveniles.
    Matched MeSH terms: Bass/growth & development; Diptera/growth & development; Simuliidae/growth & development
  7. Onychomycosis in Malaysia
    Ng KP, Saw TL, Madasamy M, Soo Hoo T
    Mycopathologia, 1999;147(1):29-32.
    PMID: 10872513
    The common etiological agents of onychomycosis are dermatophytes, molds and yeasts. A mycological nail investigation of onychomycosis using direct microscopy and culture was conducted by the Mycology Unit, Department of Medical Microbiology, University of Malaya from March 1996 to November 1998. The study involved 878 nail clippings or subungal scrapings from subjects with onychomycosis. On direct microscopy examination, 50% of the specimens were negative for fungal elements. On culture, 373 specimens had no growth; bacteria were isolated from 15 nail specimens. Among the 490 specimens with positive fungal cultures, 177 (36.1%) were dermatophytes, 173 (35.5%) were molds and 130 (26.5%) were Candida. There were 2% (10/490) mixed infections of molds, yeasts and dermatophytes. Trichophyton rubrum (115/177) and Trichophyton mentagrophytes (59/177) were the main dermatophytes isolated. The molds isolated were predominantly Aspergillus niger (61/173), Aspergillus nidulans (30/173), Hendersonula toruloidea (26/173) and Fusarium species (16/173). 96.9% of the Candida species identified were Candida albicans.
    Matched MeSH terms: Aspergillus nidulans/growth & development; Aspergillus niger/growth & development; Candida/growth & development*; Fungi/growth & development*; Fusarium/growth & development; Trichophyton/growth & development*
  8. Fulltext Identification of functionally important microRNAs from rice inflorescence at heading stage of a qDTY4.1-QTL bearing Near Isogenic Line under drought conditions
    Cheah BH, Jadhao S, Vasudevan M, Wickneswari R, Nadarajah K
    PLoS One, 2017;12(10):e0186382.
    PMID: 29045473 DOI: 10.1371/journal.pone.0186382
    A cross between IR64 (high-yielding but drought-susceptible) and Aday Sel (drought-tolerant) rice cultivars yielded a stable line with enhanced grain yield under drought screening field trials at International Rice Research Institute. The major effect qDTY4.1 drought tolerance and yield QTL was detected in the IR77298-14-1-2-10 Backcrossed Inbred Line (BIL) and its IR87705-7-15-B Near Isogenic Line (NIL) with 93.9% genetic similarity to IR64. Although rice yield is extremely susceptible to water stress at reproductive stage, currently, there is only one report on the detection of drought-responsive microRNAs in inflorescence tissue of a Japonica rice line. In this study, more drought-responsive microRNAs were identified in the inflorescence tissues of IR64, IR77298-14-1-2-10 and IR87705-7-15-B via next-generation sequencing. Among the 32 families of inflorescence-specific non-conserved microRNAs that were identified, 22 families were up-regulated in IR87705-7-15-B. Overall 9 conserved and 34 non-conserved microRNA families were found as drought-responsive in rice inflorescence with 5 conserved and 30 non-conserved families induced in the IR87705-7-15-B. The observation of more drought-responsive non-conserved microRNAs may imply their prominence over conserved microRNAs in drought response mechanisms of rice inflorescence. Gene Ontology annotation analysis on the target genes of drought-responsive microRNAs identified in IR87705-7-15-B revealed over-representation of biological processes including development, signalling and response to stimulus. Particularly, four inflorescence-specific microRNAs viz. osa-miR5485, osa-miR5487, osa-miR5492 and osa-miR5517, and two non-inflorescence specific microRNAs viz. osa-miR169d and osa-miR169f.2 target genes that are involved in flower or embryonic development. Among them, osa-miR169d, osa-miR5492 and osa-miR5517 are related to flowering time control. It is also worth mentioning that osa-miR2118 and osa-miR2275, which are implicated in the biosynthesis of rice inflorescence-specific small interfering RNAs, were induced in IR87705-7-15-B but repressed in IR77298-14-1-2-10. Further, gene search within qDTY4.1 QTL region had identified multiple copies of NBS-LRR resistance genes (potential target of osa-miR2118), subtilisins and genes implicated in stomatal movement, ABA metabolism and cuticular wax biosynthesis.
    Matched MeSH terms: Oryza/growth & development; Plant Leaves/growth & development; Plant Roots/growth & development; Flowers/growth & development
  9. Role of coaggregation in the pathogenicity and prolonged colonisation of Vibrio cholerae
    Toh YS, Yeoh SL, Yap IKS, Teh CSJ, Win TT, Thong KL, et al.
    Med Microbiol Immunol, 2019 Dec;208(6):793-809.
    PMID: 31263955 DOI: 10.1007/s00430-019-00628-3
    Cholera is an acute diarrheal illness caused by the Gram-negative bacterium Vibrio cholerae. The pathogen is known for its ability to form biofilm that confers protection against harsh environmental condition and as part of the colonisation process during infection. Coaggregation is a process that facilitates the formation of biofilm. In a preliminary in vitro study, high coaggregation index and biofilm production were found between V. cholerae with human commensals namely Escherichia coli and Enterobacter cloacae. Building upon these results, the effects of coaggregation were further evaluated using adult BALB/c mouse model. The animal study showed no significant differences in mortality and fluid accumulation ratio between treatment groups infected with V. cholerae alone and those infected with coaggregation partnership (V. cholerae with E. coli or V. cholerae with E. cloacae). However, mild inflammation was detected in both partnering pairs. Higher density of V. cholerae was recovered from faecal samples of mice co-infected with E. coli and V. cholerae in comparison with other groups at 24 h post-infection. This partnership also elicited slightly higher levels of interleukin-5 (IL-5) and interleukin-10 (IL-10). Nonetheless, the involvement of autoinducer-2 (AI-2) as the signalling molecules in quorum sensing system is not evident in this study. Since E. coli is one of the common commensals, our result may suggest the involvement of commensals in cholera development.
    Matched MeSH terms: Escherichia coli/growth & development; Vibrio cholerae/growth & development*; Enterobacter cloacae/growth & development; Biofilms/growth & development*
  10. Conochironomus (Diptera: Chironomidae) in Asia: new and redescribed species and vouchering issues
    Cranston PS
    Zootaxa, 2016 May 09;4109(3):315-31.
    PMID: 27394867 DOI: 10.11646/zootaxa.4109.3.3
    The presence of the Afro-Australian genus Conochironomus Freeman, 1961 (Diptera: Chironomidae) in Asia has been recognised only informally. An unpublished thesis included Conochironomus from Singapore, and the genus has been keyed from Malaysia without named species. Here, the Sumatran Conochironomus tobaterdecimus (Kikuchi & Sasa, 1980) comb. n. is recorded from Singapore and Thailand. The species is transferred from Sumatendipes Kikuchi & Sasa, 1980, rendering the latter a junior synonym (syn. n.) of Conochironomus Freeman. Conochironomus nuengthai sp. n. and Conochironomus sawngthai sp. n. are described as new to science, based on adult males from Chiang Mai, Thailand. All species conform to existing generic diagnoses for all life stages, with features from male and female genitalia, pupal cephalic tubercles and posterolateral 'spurs' of tergite VIII providing evidence for species distinction. Some larvae are linked to C. tobaterdecimus through molecular barcoding. Variation in other larvae, which clearly belong to Conochironomus and are common throughout Thailand, means that they cannot be segregated to species. Larval habitats include pools in river beds, urban storage reservoirs, drains with moderately high nutrient loadings, and peat swamps. Endochironomus effusus Dutta, 1994 from north-eastern India may be a congener but may differ in adult morphology, thereby precluding formal new combination until discrepancies can be reconciled. Many problems with vouchering taxonomic and molecular material are identified that need to be rectified in the future.
    Matched MeSH terms: Animal Structures/growth & development; Chironomidae/growth & development; Larva/growth & development; Pupa/growth & development
  11. Antagonistic effects of Streptomyces violaceusniger strain G10 on Fusarium oxysporum f.sp. cubense race 4: indirect evidence for the role of antibiosis in the antagonistic process
    Getha K, Vikineswary S
    J Ind Microbiol Biotechnol, 2002 Jun;28(6):303-10.
    PMID: 12032802
    Fusarium oxysporum f.sp. cubense is the causal pathogen of wilt disease of banana. A cost-effective measure of control for this disease is still not available. Streptomyces violaceusniger strain G10 acts as an antifungal agent antagonistic towards many different phytopathogenic fungi, including different pathogenic races of the Fusarium wilt pathogen. In an attempt to understand the mode of action of this antagonist in nature, the interaction between S. violaceusniger strain G10 and F. oxysporum f.sp. cubense was first studied by paired incubation on agar plates. Evidence for the in vitro antibiosis of strain G10 was demonstrated by inhibition zones in the "cross-plug" assay plates. Microscopic observations showed lysis of hyphal ends in the inhibited fungal colonies. Culture of strain G10 in liquid media produces antifungal metabolites, which showed in vitro antagonistic effects against F. oxysporum f.sp. cubense such as swelling, distortion and excessive branching of hyphae, and inhibition of spore germination. An indirect method was used to show that antibiosis is one of the mechanisms of antagonism by which strain G10 acts against F. oxysporun f.sp. cubense in soil. This study suggests the potential of developing strain G10 for the biological control of Fusarium wilt disease of banana.
    Matched MeSH terms: Fusarium/growth & development; Spores, Fungal/growth & development; Streptomyces/growth & development; Hyphae/growth & development
  12. New species and records of black flies (Diptera: Simuliidae) from Vinh Phuc Province, Vietnam
    Takaoka H, Sofian-Azirun M, Ya'cob Z, Chen CD, Lau KW, Pham HT
    Zootaxa, 2014;3838(3):347-66.
    PMID: 25081781 DOI: 10.11646/zootaxa.3838.3.6
    Four new species of black flies are described, and three others are reported as newly recorded, based on adults reared from pupae, pupae and larvae collected in and near Tam Dao National Park, Vinh Phuc Province, Vietnam. New species include Simulium (Gomphostilbia) hongthaii sp. nov., S. (G.) tamdaoense sp. nov. (both species placed in the asakoae species-group), S. (Simulium) taythienense sp. nov. and S. (S.) xuandai sp. nov. (the two latter species placed in the striatum species-group). Newly recorded species are S. (G.) brinchangense Takaoka, Sofian-Azirun & Hashim, S. (Nevermannia) aureohirtum Brunetti and S. (S.) brevipar Takaoka & Davies. These discoveries increase the number of species of black flies known in Vietnam from 21 to 28. 
    Matched MeSH terms: Animal Structures/growth & development; Larva/growth & development; Pupa/growth & development; Simuliidae/growth & development
  13. Variations in oil palm (Elaeis guineensis Jacq.) progeny response to high aluminium concentrations in solution culture
    Cristancho RJ, Hanafi MM, Omar SR, Rafii MY
    Plant Biol (Stuttg), 2011 Mar;13(2):333-42.
    PMID: 21309980 DOI: 10.1111/j.1438-8677.2010.00378.x
    Aluminium (Al) phytotoxicity is an important soil constraint that limits crop yield. The objectives of this study were to investigate how growth, physiology, nutrient content and organic acid concentration is affected by Al, and to assess the degree of Al tolerance in different oil palm progeny (OPP). Four OPPs ['A' (Angola dura × Angola dura), 'B' (Nigerian dura × Nigerian dura), 'C' (Deli dura × AVROS pisifera) and 'D' (Deli dura × Dumpy AVROS pisifera)] were grown in different Al concentrations (0, 100 and 200 μm) in aerated Hoagland solution, pH 4.4, for 80 days. We observed a severe reduction (57.5%) in shoot dry weight, and root tips were reduced by 46.5% in 200 μm Al. In 'B' and 'C', the majority of macro- and micronutrients in plants were reduced significantly by 200 μm Al, with Mg being lowered by more than 50% in roots and shoots. The 200 μm Al treatment resulted in a 56.50% reduction in total leaf area, a 20% reduction in net photosynthesis and a 17% reduction in SPAD chlorophyll value in the third leaf. Root tips (0-5 mm) showed a significant increase in oxalic acid content with increasing Al concentration (∼ 5.86-fold); progeny 'A' had the highest concentration of oxalic acid. There was a significant interaction between Al concentration × OPP on total leaf number, root volume, lateral root length, Mg and K in root and shoot tissues, and Ca and N in shoots. The OPPs could be ranked in their tolerance to Al as: 'A' > 'D' > 'B' > 'C'.
    Matched MeSH terms: Plant Leaves/growth & development; Plant Roots/growth & development; Plant Shoots/growth & development; Arecaceae/growth & development
  14. Fulltext Antibacterial activity of selected Malaysian honey
    Zainol MI, Mohd Yusoff K, Mohd Yusof MY
    BMC Complement Altern Med, 2013;13:129.
    PMID: 23758747 DOI: 10.1186/1472-6882-13-129
    Antibacterial activity of honey is mainly dependent on a combination of its peroxide activity and non-peroxide components. This study aims to investigate antibacterial activity of five varieties of Malaysian honey (three monofloral; acacia, gelam and pineapple, and two polyfloral; kelulut and tualang) against Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Pseudomonas aeruginosa.
    Matched MeSH terms: Bacillus cereus/growth & development; Escherichia coli/growth & development; Pseudomonas aeruginosa/growth & development; Staphylococcus aureus/growth & development
  15. Fulltext Long-term succession in a coal seam microbiome during in situ biostimulation of coalbed-methane generation
    Beckmann S, Luk AWS, Gutierrez-Zamora ML, Chong NHH, Thomas T, Lee M, et al.
    ISME J, 2019 03;13(3):632-650.
    PMID: 30323265 DOI: 10.1038/s41396-018-0296-5
    Despite the significance of biogenic methane generation in coal beds, there has never been a systematic long-term evaluation of the ecological response to biostimulation for enhanced methanogenesis in situ. Biostimulation tests in a gas-free coal seam were analysed over 1.5 years encompassing methane production, cell abundance, planktonic and surface associated community composition and chemical parameters of the coal formation water. Evidence is presented that sulfate reducing bacteria are energy limited whilst methanogenic archaea are nutrient limited. Methane production was highest in a nutrient amended well after an oxic preincubation phase to enhance coal biofragmentation (calcium peroxide amendment). Compound-specific isotope analyses indicated the predominance of acetoclastic methanogenesis. Acetoclastic methanogenic archaea of the Methanosaeta and Methanosarcina genera increased with methane concentration. Acetate was the main precursor for methanogenesis, however more acetate was consumed than methane produced in an acetate amended well. DNA stable isotope probing showed incorporation of 13C-labelled acetate into methanogenic archaea, Geobacter species and sulfate reducing bacteria. Community characterisation of coal surfaces confirmed that methanogenic archaea make up a substantial proportion of coal associated biofilm communities. Ultimately, methane production from a gas-free subbituminous coal seam was stimulated despite high concentrations of sulfate and sulfate-reducing bacteria in the coal formation water. These findings provide a new conceptual framework for understanding the coal reservoir biosphere.
    Matched MeSH terms: Archaea/growth & development; Sulfur-Reducing Bacteria/growth & development; Methanosarcinaceae/growth & development; Methanosarcina/growth & development; Geobacter/growth & development
  16. Synthesis, Antiphospholipase A₂, Antiprotease, Antibacterial Evaluation and Molecular Docking Analysis of Certain Novel Hydrazones
    El-Sayed NN, Alafeefy AM, Bakht MA, Masand VH, Aldalbahi A, Chen N, et al.
    Molecules, 2016 Dec 02;21(12).
    PMID: 27918459
    Some novel hydrazone derivatives 6a-o were synthesized from the key intermediate 4-Chloro-N-(2-hydrazinocarbonyl-phenyl)-benzamide 5 and characterized using IR, ¹H-NMR, 13C-NMR, mass spectroscopy and elemental analysis. The inhibitory potential against two secretory phospholipase A₂ (sPLA₂), three protease enzymes and eleven bacterial strains were evaluated. The results revealed that all compounds showed preferential inhibition towards hGIIA isoform of sPLA₂ rather than DrG-IB with compounds 6l and 6e being the most active. The tested compounds exhibited excellent antiprotease activity against proteinase K and protease from Bacillus sp. with compound 6l being the most active against both enzymes. Furthermore, the maximum zones of inhibition against bacterial growth were exhibited by compounds; 6a, 6m, and 6o against P. aeruginosa; 6a, 6b, 6d, 6f, 6l, 6m, 6n, and 6o against Serratia; 6k against S. mutans; and compounds 6a, 6d, 6e, 6m, and 6n against E. feacalis. The docking simulations of hydrazones 6a-o with GIIA sPLA₂, proteinase K and hydrazones 6a-e with glutamine-fructose-6-phosphate transaminase were performed to obtain information regarding the mechanism of action.
    Matched MeSH terms: Bacillus/growth & development; Pseudomonas aeruginosa/growth & development; Serratia/growth & development; Enterococcus faecalis/growth & development; Streptococcus mutans/growth & development
  17. Genetic variation and correlated changes in reproductive performance of a red tilapia line selected for improved growth over three generations
    Thoa NP, Hamzah A, Nguyen NH
    Anim. Reprod. Sci., 2017 Sep;184:94-101.
    PMID: 28709735 DOI: 10.1016/j.anireprosci.2017.07.003
    The present study examines genetic variation and correlated changes in reproductive performance traits in a red tilapia (Oreochromis spp.) population selected over three generations for improved growth. A total of 328 breeding females (offspring of 111 sires and 118 dams) had measurements of body weight prior to spawning (WBS), number of fry at hatching (NFH), total fry weight (TFW) and number of dead fry (NDF) or mortality of fry including unhatched eggs at hatching (MFH). Restricted maximum likelihood (REML) analysis in a multi-trait model showed that there are heritable genetic components for all traits studied. The heritability for WBS was very high (0.80). The estimates for traits related to fecundity (NFH, TFW) and survival (NDF) were low and they were associated with high standard errors. Genetic correlations of WBS with other reproductive performance traits (NFH, TFW and NDF) were generally positive. However, NFH was negatively correlated genetically with TFW. As expected, body measurements during growth stage exhibited strong positive genetic correlations with WBS. The genetic correlations between body traits and reproductive performance (NFH, TFW, NDF) were not significant. Correlated responses in reproductive traits were measured as changes in least squares means between generations or spawning years. Except for WBS that increased with the selection programs, the phenotypic changes in other reproductive traits observed were not statistically significant (P>0.05). It is concluded that the selection program for red tilapia has resulted in very little changes in reproductive performance of the animals after three generations. However, periodic monitoring of genetic changes in fecundity and fitness related traits such as NDF or MFH should be made in selective breeding programs for red tilapia.
    Matched MeSH terms: Tilapia/growth & development
  18. Performance of Willem's dental age estimation method in children: A systematic review and meta-analysis
    Mohd Yusof MYP, Wan Mokhtar I, Rajasekharan S, Overholser R, Martens L
    Forensic Sci Int, 2017 Nov;280:245.e1-245.e10.
    PMID: 28958768 DOI: 10.1016/j.forsciint.2017.08.032
    Through numerous validation and method comparison studies on different populations, the Willems method exhibited a superior accuracy. This article aims to systematically examine how accurate the application of Willems dental age method on children of different age groups and its performance based on various populations and regions. A strategic literature search of PubMed, MEDLINE, Web of Science, EMBASE and hand searching were used to identify the studies published up to September 2014 that estimated the dental age using the Willems method (modified Demirjian), with a populations, intervention, comparisons and outcomes (PICO) search strategy using MeSH keywords, focusing on the question: How much Willems method deviates from the chronological age in estimating age in children? Standardized mean differences were calculated for difference of dental age to chronological age by using random effects model. Subgroup analyses were performed to evaluate potential heterogeneity. Of 116 titles retrieved based on the standardized search strategy, only 19 articles fulfilled the inclusion criteria for quantitative analysis. The pooled estimates were separately kept as underestimation (n=7) and overestimation (n=12) of chronological age groups for both genders according to primary studies. On absolute values, females (underestimated by 0.13; 95% CI: 0.09-0.18 and overestimated by 0.27; 95% CI: 0.17-0.36) exhibited better accuracy than males (underestimated by 0.28; 95% CI: 0.14-0.42 and overestimated by 0.33; 95% CI: 0.22-0.44). For comparison purposes, the overall pooled estimate overestimated the age by 0.10 (95% CI: -0.06 to 0.26) and 0.09 (95% CI: -0.09 to 0.19) for males and females, respectively. There was no significant difference between the young and older child in subgroup analysis using omnibus test. The mean age between different regions exhibited no statistically significant. The use of Willems method is appropriate to estimate age in children considering its accuracy among different populations, investigators and age groups.
    Matched MeSH terms: Tooth/growth & development
  19. Fulltext First integrative trend analysis for a great ape species in Borneo
    Santika T, Ancrenaz M, Wilson KA, Spehar S, Abram N, Banes GL, et al.
    Sci Rep, 2017 07 07;7(1):4839.
    PMID: 28687788 DOI: 10.1038/s41598-017-04435-9
    For many threatened species the rate and drivers of population decline are difficult to assess accurately: species' surveys are typically restricted to small geographic areas, are conducted over short time periods, and employ a wide range of survey protocols. We addressed methodological challenges for assessing change in the abundance of an endangered species. We applied novel methods for integrating field and interview survey data for the critically endangered Bornean orangutan (Pongo pygmaeus), allowing a deeper understanding of the species' persistence through time. Our analysis revealed that Bornean orangutan populations have declined at a rate of 25% over the last 10 years. Survival rates of the species are lowest in areas with intermediate rainfall, where complex interrelations between soil fertility, agricultural productivity, and human settlement patterns influence persistence. These areas also have highest threats from human-wildlife conflict. Survival rates are further positively associated with forest extent, but are lower in areas where surrounding forest has been recently converted to industrial agriculture. Our study highlights the urgency of determining specific management interventions needed in different locations to counter the trend of decline and its associated drivers.
    Matched MeSH terms: Pongo pygmaeus/growth & development*
  20. Temporal changes in arthropod activity in tropical anthropogenic forests
    Brandon-Mong GJ, Littlefair JE, Sing KW, Lee YP, Gan HM, Clare EL, et al.
    Bull. Entomol. Res., 2018 Dec;108(6):792-799.
    PMID: 29441836 DOI: 10.1017/S000748531800010X
    Arthropod communities in the tropics are increasingly impacted by rapid changes in land use. Because species showing distinct seasonal patterns of activity are thought to be at higher risk of climate-related extirpation, global warming is generally considered a lower threat to arthropod biodiversity in the tropics than in temperate regions. To examine changes associated with land use and weather variables in tropical arthropod communities, we deployed Malaise traps at three major anthropogenic forests (secondary reserve forest, oil palm forest, and urban ornamental forest (UOF)) in Peninsular Malaysia and collected arthropods continuously for 12 months. We used metabarcoding protocols to characterize the diversity within weekly samples. We found that changes in the composition of arthropod communities were significantly associated with maximum temperature in all the three forests, but shifts were reversed in the UOF compared with the other forests. This suggests arthropods in forests in Peninsular Malaysia face a double threat: community shifts and biodiversity loss due to exploitation and disturbance of forests which consequently put species at further risk related to global warming. We highlight the positive feedback mechanism of land use and temperature, which pose threats to the arthropod communities and further implicates ecosystem functioning and human well-being. Consequently, conservation and mitigation plans are urgently needed.
    Matched MeSH terms: Arecaceae/growth & development
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