Browse publications by year: 2023

  1. Reeve AH, Gower G, Pujolar JM, Smith BT, Petersen B, Olsson U, et al.
    Evol Lett, 2023 Feb 01;7(1):24-36.
    PMID: 37065434 DOI: 10.1093/evlett/qrac006
    Tropical islands are renowned as natural laboratories for evolutionary study. Lineage radiations across tropical archipelagos are ideal systems for investigating how colonization, speciation, and extinction processes shape biodiversity patterns. The expansion of the island thrush across the Indo-Pacific represents one of the largest yet most perplexing island radiations of any songbird species. The island thrush exhibits a complex mosaic of pronounced plumage variation across its range and is arguably the world's most polytypic bird. It is a sedentary species largely restricted to mountain forests, yet it has colonized a vast island region spanning a quarter of the globe. We conducted a comprehensive sampling of island thrush populations and obtained genome-wide SNP data, which we used to reconstruct its phylogeny, population structure, gene flow, and demographic history. The island thrush evolved from migratory Palearctic ancestors and radiated explosively across the Indo-Pacific during the Pleistocene, with numerous instances of gene flow between populations. Its bewildering plumage variation masks a biogeographically intuitive stepping stone colonization path from the Philippines through the Greater Sundas, Wallacea, and New Guinea to Polynesia. The island thrush's success in colonizing Indo-Pacific mountains can be understood in light of its ancestral mobility and adaptation to cool climates; however, shifts in elevational range, degree of plumage variation and apparent dispersal rates in the eastern part of its range raise further intriguing questions about its biology.
  2. Godman B, Wladysiuk M, McTaggart S, Kurdi A, Allocati E, Jakovljevic M, et al.
    Biomed Res Int, 2023;2023:9757348.
    PMID: 37065720 DOI: 10.1155/2023/9757348
    [This corrects the article DOI: 10.1155/2021/9996193.].
  3. Jiangseubchatveera N, Saechan C, Petchsomrit A, Treeyaprasert T, Leelakanok N, Prompanya C
    Trop Life Sci Res, 2023 Mar;34(1):1-17.
    PMID: 37065791 DOI: 10.21315/tlsr2023.34.1.1
    Lactuca sativa L. is an economically important vegetable that contains numerous phytochemicals. This study aimed to determine the phytochemicals in three lettuce cultivars (red oak, red coral, and butterhead) and assess their total phenolics, total flavonoids and antioxidant activities. The dried leaves of each lettuce cultivar were macerated with hexane, ethyl acetate (EtOAc), and 95% ethanol (EtOH). Total phenolics, total flavonoids, and antioxidant activities from the three solvent extracts were measured. The phytochemical screening showed that the leaves from the three lettuce cultivars contained flavonoids, hydrolyzable tannins, coumarins, steroids, and phenolic compounds. While the EtOAc fraction of the red coral lettuce showed the highest total phenolic content (9.747 ± 0.021 mg gallic acid equivalent/g) and the hexane fraction of the butterhead lettuce contained the highest flavonoids (7.065 ± 0.005 mg quercetin equivalent/g). In the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) assay, the EtOAc fraction of the red coral lettuce had the highest antioxidant capacity with an IC50 of 0.277 ± 0.006 mg/mL, whereas, in the ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) assay, the 95% EtOH of the red coral lettuce had the highest antioxidant capacity with an IC50 of 0.300 ± 0.002 mg/mL. All three lettuce cultivars contained high levels of phenolic content and flavonoids, which are the source of antioxidant activities. These lettuce cultivars, especially the red coral lettuce, are a potential source of natural antioxidants. Further research on the application of natural antioxidants is required to investigate the therapeutic or the neutraceutical implication of the lettuce cultivars.
  4. Jaapar MS, Chung ELT, Nayan N, Muniandy KV, Hamdan MHM, Jusoh S, et al.
    Trop Life Sci Res, 2023 Mar;34(1):67-83.
    PMID: 37065792 DOI: 10.21315/tlsr2023.34.1.5
    Limited data are available regarding the effects of Brachiaria decumbens on sheep's growth performance at different times. Therefore, this current study focused on sheep's nutrient apparent digestibility, feed efficiency, body index, and growth hormone when they are fed with low and high levels of B. decumbens diets. A total of 30 six-month-old male Dorper cross sheep were divided randomly into three treatment groups with 10 sheep per treatment. Treatment 1 (control) sheep were fed with Pennisetum purpureum and pellets as the basal diet, whereas Treatment 2 and 3 sheep were fed with feed mixed with low (10%) and high (60%) levels of B. decumbens, respectively. The study was conducted in two phases consisting of short-term feeding (seven days) and long-term feeding (90 days). Throughout the experiment, daily fecal voided were collected in the morning for seven days continuous before the end of each feeding phases for the determination of nutrient apparent digestibility. The amount of feed offered and refusals plus body weight gain were recorded daily to determine the feed efficiency (FE). Besides, the body measurements of each sheep from every treatment were measured weekly and blood samples were collected for the analysis of growth hormone (GH) concentration. There were significant differences (p < 0.05) in the nutrient apparent digestibility, growth performance, body measurement, and GH concentration among treatment sheep throughout the study period. Treatment 3 sheep fed with 60% of B. decumbens diet revealed the lowest dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) digestibility during the long-term feeding. Likewise, Treatment 3 (T3) sheep had the lowest total bodyweight gain, average daily gain, total feed intake, and daily feed intake among treatment sheep. The heart girth index (HGI) of T3 sheep was also significantly lower during the short-term feeding. Moreover, the GH concentration of T3 sheep was significantly lower as compared to the control that decreases steadily throughout the study period. In conclusion, high levels of B. decumbens showed the most significant results out of all three treatments indicating the presence of saponins, which produce negative effects on the sheep's overall performance.
  5. Prasetia HA, Budiawan S, Syahputra A, Umiarsih R, Pangastuweni R, Fauzidanty MR, et al.
    Trop Life Sci Res, 2023 Mar;34(1):19-39.
    PMID: 37065793 DOI: 10.21315/tlsr2023.34.1.2
    Freeze-process has been applied in preserving many fresh horticultural commodities addressed to the medium-distancing distribution. In this study, effect of freezing process and storage time on durian's attributes degradation was observed. 100 durian fruits were treated with two-level combinations of freezing process. The first level involves the freezing of the said fruit at -15°C for two different freezing times, that is 10 min (treatment A) and 20 min (treatment B). Followed by frozen-storage for -10°C for 0, 10, 20 and 30 days. At different interval time, the frozen samples were thawed at 4°C for 24h. Then, physical, chemical, and sensory parameters were periodically assessed. The result showed that treatment B provide a significantly better output than treatment A. This is proven through a lower weight loss, brighter and lighter yellow of the pulp, softer pulp, lower value of moisture content on the pulp, and a remained stable of succinate acid's profile. Furthermore, based on the preference evaluation test, the fruits were accepted by respondents.
  6. Khianngam S, Meetum P, Chiangmai PN, Tanasupawat S
    Trop Life Sci Res, 2023 Mar;34(1):219-239.
    PMID: 37065794 DOI: 10.21315/tlsr2023.34.1.12
    Indole-3-acetic acid (IAA) is one of the most physiologically active auxins produced by rhizobacteria and is potentially applied for agriculture. Two endophytic bacteria, VR2 and MG9, isolated from the root of Chrysopogon zizanioides (L.) collected at Cha-Am, and the leaf of Bruguiera cylindrica (L.) Blume collected from a mangrove forest at Ban Laem, Phetchaburi Province, Thailand, were taxonomic characterised based on their phenotypic characteristics and 16S rRNA gene analysis. Strain VR2 was closely related to Enterobacter hormaechei CIP 103441T (99.6% similarity), while strain MG9 was closely related to Bacillus aryabhattai B8W22T (99.9% similarity). Consequently, they were identified as Enterobacter hormaechei and Bacillus aryabhattai, respectively. The IAA production of VR2 and MG9 strains are determined and applied to rice seeds for their root and shoot germination. Strains VR2 and MG9 greatly produced a yield of IAA, 246.00 and 195.55 μg/mL in 1,000 μg/mL of L-tryptophan at pH 6 for 48 h. They showed no significant differences in IAA to root and shoot development. However, the bacterial IAA exhibited potential nearby synthetic IAA, which had a significant effect compared to the control. IAA produced from these two strains might preferably trim down the use of synthetic IAA and could contribute to sustainable agriculture.
  7. Baharudin NS, Tah MMTM, Zulkifli SZ, Ab Ghani NI, Noor HM, Sabar Sabal NH
    Trop Life Sci Res, 2023 Mar;34(1):151-183.
    PMID: 37065795 DOI: 10.21315/tlsr2023.34.1.10
    Deforestation in Cameron Highlands, Malaysia has increased significantly in the past few years to accommodate the growing population of Cameron Highlands. This led to a rapid urbanisation in Cameron Highlands which increased anthropogenic activities, causing degradation of the natural environment. Such environmental changes highlight the necessity of wildlife and resource inventories of available forested areas to improve existing conservation and management plans, especially for threatened taxa such as the non-volant small mammals. However, very few studies are known to focus on the effect of deforestation on non-volant small mammals, especially in the adjacent forest. This survey aimed to document non-volant small mammals from four habitat types (restoration areas, boundary, disturbed and undisturbed areas) of Terla A and Bertam, and undisturbed forest of Bukit Bujang Forest Reserve, Cameron Highlands, Malaysia. Samplings were conducted in two phases between August 2020 to January 2021. A total of 80 live traps were deployed along the transect lines in all three study sites, and 10 camera traps were set randomly in each forested area. Results demonstrated that species diversity (H') is higher at Terla A Forest Reserve compared to Bertam and Bukit Bujang Forest Reserve. In contrast, species diversity in the boundary area (S = 8, H' = 2.025) and disturbed forest area (S = 8, H' = 1.992) had similar number of species (S) compared to others study habitat; restoration area had the lowest species diversity (S = 3, H' = 0.950). Berylmys bowersi was the most captured species from trappings and Lariscus insignis was the most frequently recorded species from camera trappings for all study sites. The results of the survey provided new information on non-volant small mammals in Cameron Highlands for future research, conservation, and management.
  8. Tubongbanua RM, Mendez NP, Amoroso VB
    Trop Life Sci Res, 2023 Mar;34(1):139-150.
    PMID: 37065796 DOI: 10.21315/tlsr2023.34.1.9
    Amyema are epiphytic hemiparasitic plants on different types of woody host plants and are abundant in temperate, subtropical, and tropical regions. In Marilog Forest Reserve, Southern Philippines, two Philippine endemic species of Amyema were recorded, viz., Amyema curranii (Merr.) Danser and A. seriata (Merr.) Barlow. In this study, these two species were compared and examined for their morphology and anatomy. Data revealed that the two Amyema species are morphologically distinct, with A. curranii having lanceolate leaves, pink flowers, and red fruits, whereas A. seriata has obovate leaves, red flowers, and yellow fruits. For the morpho-anatomy, A. curranii has a single-layered epidermis, paracytic stomata, collateral open vascular bundles, the Eustele type of stele with pith at the center, and the inferior free central type with a hairy ovary wall. Meanwhile, A. seriata has a pinkish, single-layered epidermis, paracytic stomata, collateral open vascular bundles, a eustele type of stele with the presence of pith at the center, and an inferior free central ovary type. As a result, employing these species' gross morphology and anatomy could scrutinise future evaluations and taxonomic placements.
  9. Safithri M, Bintang M, Syaefudin
    Trop Life Sci Res, 2023 Mar;34(1):41-50.
    PMID: 37065797 DOI: 10.21315/tlsr2023.34.1.3
    Previous studies had reported antihyperglycemic activity in vitro, in vivo and in silico of red betel (Piper crocatum) extract, which was associated with its polyphenolic, tannins, alkaloids, and flavonoids compounds. This study aimed to determine blood glucose level, Langerhans pancreas, lipid profile and bodyweight of streptozotocin-induced diabetic rats after administrating red betel combination extract. Red betel combination extract is composed of red betel extract that was combined with ginger and cinnamon extracts. 16 male rats (Sprague Dawley) were divided randomly into two controls groups (Normal and diabetic groups; orally administered with 2 mL of aquadest for 14 days) and two extract groups (diabetic groups; orally administered with red betel combination extract 9 mL/kg BW and 13.5 mL/kg BW). Results showed that the administration of red betel combination extract for 14 days (9 mL/kg BW dosage) decreased the rat's blood glucose level up to 55.42%, which was significantly different (p < 0.05) compared to the rat's blood glucose levels on day 3. While the combination extract (dosages 9 mL/kg BW and 13.5 mL/kg BW) increased the numbers of rat Langerhans islets up to 10.9%-30.6%. The level of rat's blood high-density lipoprotein (HDL) and triglyceride levels in the diabetic control group were significantly different (p < 0.05) compared to that of the diabetic with red betel combination extract and normal groups. The treatment orally with red betel combination extract (various dosages) for 14 days suppressed the weight loss of rats by 10%-11%.
  10. Rozman NAS, Yenn TW, Ring LC, Ab Rashid S, Wen-Nee T, Lim JW
    Trop Life Sci Res, 2023 Mar;34(1):279-291.
    PMID: 37065798 DOI: 10.21315/tlsr2023.34.1.15
    Microbial infection is a frequent complication of diabetic foot ulcers, with up to 82% of ulcers being infected at the initial stage of diabetes. Furthermore, the emergence of beta lactam resistant pathogens managed to eliminate the use of beta lactam antibiotics as a chemotherapeutic alternative. This further increases the amputation and mortality rate. Hence, the aim of this study is to evaluate antimicrobial efficacy of a ketone derivative 2-octylcyclopentanone against diabetic wound pathogens. The inhibitory activity of the compound was determined using disc diffusion and broth microdilution assay. Generally, 2-octylcyclopentanone showed broad-spectrum antimicrobial activity, particularly against beta lactam resistant pathogens. The compound showed comparably better antimicrobial activity than all reference antibiotics, including chloramphenicol, streptomycin, ampicillin and penicillin. In addition, the same compound also inhibits a clinically isolated Pseudonomas aeruginosa that was resistant to all reference antibiotics. The activity was microbicidal based on the low minimal lethality concentration recorded, particularly on MRSA, P. aeruginosa and Candida utilis. The killing efficiency of the compound was concentration dependent. During kill curve analysis, the inhibitory activity of 2-octylcyclopentanone was concentration and time-dependent. 99.9% of reduction of bacterial growth was observed. MRSA and P. aeruginosa, two significant diabetic wound infections, are totally inhibited by the molecule at a concentration of minimum lethality concentration. In short, 2-octylcyclopentanone exhibited significant inhibitory towards wide range of diabetic wound pathogens. Which is considered crucial since it will provide a safe and effective alternative treatment for diabetic ulcer infection.
  11. Suis MAF, Miun J, Tingkoi L, Hastie AYL, Chyang ACY, Nilus R
    Trop Life Sci Res, 2023 Mar;34(1):261-277.
    PMID: 37065799 DOI: 10.21315/tlsr2023.34.1.14
    Sabah contributes 4.2 million hectares to the total Heart of Borneo (HoB) areas. Some of the forest reserves in the HoB are newly gazetted as Totally Protected Forest. Hence, their mammal diversity has to be comprehensively documented. This study aims to record the presence of terrestrial mammal species, and assess the prevalence of poaching in selected forest reserves within the Sabah HoB area. A total of 15 forest reserves were surveyed within a 5-year timeframe which recorded 60 terrestrial mammal species, including 21 Bornean endemics. The variation in total enumerated mammal species in the study sites may be derived from unequal sampling efforts, geographical factors and anthropogenic influences. The intensity of poaching within the study sites is high. Though this study is a rapid assessment, it created baseline information for mammal diversity in some of the least studied forest reserves in Sabah, important for conservation of its terrestrial mammals.
  12. Surawut S, Suntara K, Puckdee W, Kunsook C, Kanjanavas P, Kompatiparn A, et al.
    Trop Life Sci Res, 2023 Mar;34(1):85-98.
    PMID: 37065801 DOI: 10.21315/tlsr2023.34.1.6
    The objective of this study was to investigate the mixed culture of Bacillus subtilis, B. licheniformis and B. megaterium to control acute hepatopancreatic necrosis disease (AHPND) or EMS (Early Mortality Syndrome) in white shrimp Litopenaeus vannamei as a model. The infected shrimps with Vibrio parahaemolyticus AHPND strain were divided into tanks and different feeding of either B. subtilis, B. licheniformis, B. megaterium or all Bacillus strains. The infected shrimps that were fed with a mixed culture of Bacillus showed significantly highest survival rate and revealed lower percent detection of V. parahaemolyticus AHPND strain by Polymerase Chain Reaction (PCR) (57.14%) with a small amount of viability count in their hepatopancreas. In contrast, the infected shrimps that were fed with each of B. subtilis, B. licheniformis or B. megaterium, revealed the spread of V. parahaemolyticus AHPND strain in all tissue by PCR detection (86.67%-100%) with a large amount of viability count (3.53 - 4.24 × 103 CFU/g). This study indicated that the mixed culture of Bacillus subtilis, B. licheniformis and B. megaterium could control the dissemination of V. parahaemolyticus in shrimps, especially in hepatopancreatic that is the target tissue of AHPND in white shrimp (L. vannamei). The result of this study revealed the efficiency and mechanism of the mixed culture of B. subtilis, B. licheniformis and B. megaterium to control the virulence of AHPND and support the application of this mixed culture in aquaculture of shrimp farms to avoid chemical and antibiotic treatment by using it as a biological control.
  13. Zaidi N, Haron MN, Komilus CF, Lananan F, Chew HH, Yaakub N, et al.
    Trop Life Sci Res, 2023 Mar;34(1):241-259.
    PMID: 37065802 DOI: 10.21315/tlsr2023.34.1.13
    Reproductive health and male fertility are closely related to dietary practices. In recent years, Malaysia has shown a lot of interest in using herbal plants as dietary supplements or in the treatment of numerous diseases. Aquilaria malaccensis, commonly known as karas or gaharu, has recently gained attention for its potential to cure many diseases due to its pharmacological properties. However, studies on its effect on male fertility and reproductive organs are very scarce. This study was conducted to determine the effect of A. malaccensis on male reproductive organs' weight (testis, epididymis, prostate gland and seminal vesicle) and sperm quality (sperm count, sperm morphology and sperm motility) in adult Sprague Dawley rats. Twenty-four male Sprague Dawley rats were allocated into four treatment groups; Control (C: 1 mL of distilled water, n = 6), Treatment 1 (T1: 1 g A. malaccensis/kg body weight, n = 6), Treatment 2 (T2: 2 g A. malaccensis/kg body weight, n = 6) and Treatment 3 (T3: 3 g A. malaccensis/kg body weight, n = 6), respectively. Distilled water and A. malaccensis were administered by oral gavage once daily for 28 days. The rats were euthanised on Day 29 for assessment of reproductive organs' weight and sperm quality. Result shows that weight of testis, epididymis, prostate gland, seminal vesicle and sperm motility did not differ (p > 0.05) among control and treated groups. A significant increase (p < 0.05) of sperm number (1.36 × 10-6) and a decrease (p < 0.05) in percentage of the abnormal sperm (8.17%) were observed in T1 group when compared to Control group. Incremental dosage of A. malaccensis seemed to decrease number of sperm (T3: 0.78 × 10-6 < T1: 1.36 × 10-6 with p < 0.05) and increase percentage of abnormal sperm (T3: 18.83% > T2: 12.17% > T1: 8.17% with p < 0.05). In conclusion, the administration of either 1, 2 or 3 grams of A. malaccensis did not alter the reproductive organs' weight and sperm motility. However, the higher concentration of A. malaccensis consumed by the rats seemed to have detrimental effects on the number and morphology of sperm.
  14. Kasan NA, Ikhwanuddin M, Manan H, Zakaria NS, Kamaruzzan AS, Rahim AIA, et al.
    Trop Life Sci Res, 2023 Mar;34(1):51-66.
    PMID: 37065803 DOI: 10.21315/tlsr2023.34.1.4
    In order to determine the safety level of water parameters and nutrients in the natural environment of fish and freshwater prawn in Nyatuh River, Terengganu, Malaysia, it is necessary to conduct an assessment of water quality parameters. Due to its important, a study was conducted to assess the water quality parameter and nutrients contents from Nyatuh River of Setiu Terengganu in relations to the population of freshwater prawn, Macrobrachium rosenbergii caught along the Nyatuh River basin. Total of four expeditions and five stations at different tidal condition for the water quality parameter were assessed during the study. From the results achieved, the overall temperature varied between (26.56°C-29.30°C), dissolved oxygen, DO (3.59 mg/L-6.50 mg/L), pH (4.99-7.01), salinity (0.01ppt-4.22ppt), depth (2.71 m-5.54 m) while for ammonia (0.01 mg/L-0.24 mg/L), nitrite (0.01 mg/L-0.05 mg/L) and phosphate (0.01 mg/L-0.12 mg/L). While the number of prawns caught are 176, 160, 102 and 68 for Expeditions 1, 2, 4 and 3, respectively. Possibly, the heterogeneous number of prawns caught is a result of significant differences in water level depth during high tides and low tides, as well as a fluctuation in the ammonia concentration levels in each of the stations and expeditions. For statistical analysis, the temperature showed no significant difference between the expedition, stations and tidal. That is p = 0.280, p > 0.05 and F = 1.206, respectively. While dissolved oxygen, DO, showed no significant difference as well, that is p = 0.714, p > 0.05 and F = 0.737. However, the level of water depth was significantly different between expedition, station and tidal, that is p = 0.000, p < 0.05 and F = 3.120. Ammonia, on the other hand shows no significant difference between expedition, station and tidal, that is p = 0.476, p > 0.05 and F = 0.973. The same goes for nitrite and phosphate concentration. There was no significant difference between expedition, stations and tidal, that is p = 0.569, p > 0.05 and F = 0.879 and p = 0.247, p > 0.05, F = 1.255, respectively. In Expedition 1, the good water quality parameter and very low ammonia concentration resulted in a larger prawn population as compared to other expeditions. The distribution or mixture of prawns caught is heterogeneous at different stations due to the significant differences in water depth and also to the fluctuation in water quality due to varying ammonia levels. In conclusion, the water quality in Nyatuh River fluctuated across expeditions, stations, and tides, as well as significant differences in water level depths between high and low tides. Due to the rapid growth and importance of industrial and aquaculture operations along the river, extra attention should be devoted to avoid the impact of excessive pollutant in order to protect the ecosystem.
  15. Okotie HO, Anjuwon TM, Okonkwo OL, Ameh DA, James DB
    Trop Life Sci Res, 2023 Mar;34(1):121-138.
    PMID: 37065804 DOI: 10.21315/tlsr2023.34.1.8
    Oxidative stress and inflammation have been proven to be implicated in the pathogenesis of type 2 diabetes. Recent studies showed that Ethulia conyzoides had in-vitro antioxidant activity. This study investigated the in-vivo antidiabetic, antioxidant, and anti-inflammatory potential of the residual aqueous fraction of Ethulia conyzoides in type 2 diabetic-induced male Wistar rats. Sub-acute antidiabetic studies were done with varying doses (100, 200, and 400 mg/kg body weight) of residual aqueous fraction for 21 days. Blood glucose levels, serum insulin, and in vivo antioxidant and pro-inflammatory cytokines-tumour necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) -were measured at the end of the treatment. When rats were given different concentrations of residual aqueous fraction, there was a significant (p < 0.05) reduction in blood glucose, malondialdehyde (MDA), IL-1β, and TNF-α levels, as well as a significant (p < 0.05) increase in SOD (superoxide dismutase), catalase and insulin levels when compared to the diabetic control group. Furthermore, the 400 mg/kg body weight dosage concentration was found to be the most effective. This result suggests that the residual aqueous fraction of Ethulia conyzoides possesses significant antidiabetic, antioxidant and anti-inflammatory activities.
  16. Lau WLS, Teng ST, Lim HC, Hii KS, Leong SCY, Leaw CP, et al.
    Trop Life Sci Res, 2023 Mar;34(1):99-120.
    PMID: 37065805 DOI: 10.21315/tlsr2023.34.1.7
    Species of the genus Chattonella (Raphidophyceae) are a group of marine protists that are commonly found in coastal waters. Some are known as harmful microalgae that form noxious blooms and cause massive fish mortality in finfish aquaculture. In Malaysia, blooms of Chattonella have been recorded since the 1980s in the Johor Strait. In this study, two strains of Chattonella were established from the strait, and morphological examination revealed characteristics resembling Chattonella subsalsa. The molecular characterization further confirmed the species' identity as C. subsalsa. To precisely detect the cells of C. subsalsa in the environment, a whole-cell fluorescence in-situ hybridisation (FISH) assay was developed. The species-specific oligonucleotide probes were designed in silico based on the nucleotide sequences of the large subunit (LSU) and internal transcribed spacer 2 (ITS2) of the ribosomal DNA (rDNA). The best candidate signature regions in the LSU-rRNA and ITS2-rDNA were selected based on hybridisation efficiency and probe parameters. The probes were synthesised as biotinylated probes and tested by tyramide signal amplification with FISH (FISH-TSA). The results showed the specificity of the probes toward the target cells. FISH-TSA has been proven to be a potential tool in the detection of harmful algae in the environment and could be applied to the harmful algal monitoring program.
  17. Nisaa AA, Oon CE, Sreenivasan S, Balakrishnan V, Rajendran D, Tan JJ, et al.
    Prev Nutr Food Sci, 2023 Mar 31;28(1):1-9.
    PMID: 37066035 DOI: 10.3746/pnf.2023.28.1.1
    We previously reported that breast milk from women with (W) or without (WO) vaginal yeast infection during pregnancy differs in its immunological and antimicrobial properties, especially against pathogenic vaginal Candida sp.. Here, we investigated the differences in microbiota profiles of breast milk from these groups. Seventy-two breast milk samples were collected from lactating mothers (W, n=37; WO, n=35). The DNA of bacteria was extracted from each breast milk sample for microbiota profiling by 16S rRNA gene sequencing. Breast milk from the W-group exhibited higher alpha diversity than that from the WO-group across different taxonomic levels of class (P=0.015), order (P=0.011), family (P=0.020), and genus (P=0.030). Compositional differences between groups as determined via beta diversity showed marginal differences at taxonomic levels of phylum (P=0.087), family (P=0.064), and genus (P=0.067). The W-group showed higher abundances of families Moraxellaceae (P=0.010) and Xanthomonadaceae (P=0.008), and their genera Acinetobacter (P=0.015), Enhydrobacter (P=0.015), and Stenotrophomonas (P=0.007). Meanwhile, the WO-group showed higher abundances of genus Staphylococcus (P=0.046) and species Streptococcus infantis (P=0.025). This study shows that, although breast milk composition is affected by vaginal infection during pregnancy, this may not pose a threat to infant growth and development.
  18. Lee YL, Zaini AA, Idris AN, Abdullah RA, Wong JS, Hong JS, et al.
    J Paediatr Child Health, 2023 Jul;59(7):879-884.
    PMID: 37066819 DOI: 10.1111/jpc.16405
    AIMS: Knowledge on the spectrum of thyroid disorders amongst Turner syndrome (TS) patients in Southeast Asia is limited. This study aimed to evaluate the prevalence of thyroid autoimmunity, the spectrum of autoimmune thyroid disease and association with age and karyotype amongst Malaysian TS girls.

    METHODS: A cross-sectional study was conducted at 11 paediatric endocrine units in Malaysia. Blood samples for antithyroglobulin antibodies, antithyroid peroxidase antibodies and thyroid function test were obtained. In patients with pre-existing thyroid disease, information on clinical and biochemical thyroid status was obtained from medical records.

    RESULTS: Ninety-seven TS patients with a mean age of 13.4 ± 4.8 years were recruited. Thyroid autoimmunity was found in 43.8% of TS patients. Nineteen per cent of those with thyroid autoimmunity had autoimmune thyroid disease (Hashimoto thyroiditis in 7.3% and hyperthyroidism in 1% of total population). Patients with isochromosome X and patients with 45,X mosaicism or other X chromosomal abnormalities were more prone to have thyroid autoimmunity compared to those with 45,X karyotype (OR 5.09, 95% CI 1.54-16.88, P = 0.008 and OR 3.41, 95% CI 1.32-8.82, P = 0.01 respectively). The prevalence of thyroid autoimmunity increased with age (33.3% for age 0-9.9 years; 46.8% for age 10-19.9 years and 57.1% age for 20-29.9 years) with autoimmune thyroid disease detected in 14.3% during adulthood.

    CONCLUSION: Thyroid autoimmunity was significantly associated with the non 45,X karyotype group, particularly isochromosome X. Annual screening of thyroid function should be carried out upon diagnosis of TS until adulthood with more frequent monitoring recommended in the presence of thyroid autoimmunity.

    MeSH terms: Adolescent; Adult; Autoantibodies/genetics; Child; Child, Preschool; Chromosome Aberrations; Cross-Sectional Studies; Female; Humans; Infant; Infant, Newborn; Autoimmunity; Isochromosomes*; Young Adult
  19. Prabhu NB, Vasishta S, Bhat SK, Joshi MB, Kabekkodu SP, Satyamoorthy K, et al.
    Environ Sci Pollut Res Int, 2023 May;30(23):64025-64035.
    PMID: 37060405 DOI: 10.1007/s11356-023-26820-w
    Polycystic ovarian syndrome (PCOS) is a complicated endocrinopathy with an unclear etiology that afflicts fertility status in women. Although the underlying causes and pathophysiology of PCOS are not completely understood, it is suspected to be driven by environmental factors as well as genetic and epigenetic factors. Bisphenol A (BPA) is a weak estrogenic endocrine disruptor known to cause adverse reproductive outcomes in women. A growing relevance supports the notion that BPA may contribute to PCOS pathogenesis. Due to the indeterminate molecular mechanisms of BPA in PCOS endocrinopathy, we sought liquid chromatography with tandem mass spectrometry (LC-MS/MS), a metabolomics strategy that could generate a metabolic signature based on urinary BPA levels of PCOS and healthy individuals. Towards this, we examined urinary BPA levels in PCOS and healthy women by ELISA and performed univariate and chemometric analysis to distinguish metabolic patterns among high and low BPA in PCOS and healthy females, followed by pathway and biomarker analysis employing MetaboAnalyst 5.0. Our findings indicated aberrant levels of certain steroids, sphingolipids, and others, implying considerable disturbances in steroid hormone biosynthesis, linoleic, linolenic, sphingolipid metabolism, and various other pathways across target groups in comparison to healthy women with low BPA levels. Collectively, our findings provide insight into metabolic signatures of BPA-exposed PCOS women, which can potentially improve management strategies and precision medicine.
    MeSH terms: Chromatography, Liquid; Female; Humans; Plasma; Tandem Mass Spectrometry
  20. Flora B, Kumar R, Tiwari P, Kumar A, Ruokolainen J, Narasimhan AK, et al.
    J Mech Behav Biomed Mater, 2023 Jun;142:105845.
    PMID: 37060714 DOI: 10.1016/j.jmbbm.2023.105845
    A successful attempt has been made to improve the mechanical properties of Hydroxyapatite (HAp) and reduced graphene oxide (rGO) composite nanoparticles (NPs). Various proportions of HAp and rGO were synthesized to improve the mechanical properties. HAp NPs were prepared using the wet precipitation method and further calcined to form crystalline particles. The physicochemical characterization of the HAp NPs revealed that the crystalline size and percentage of crystallinity were calculated to be 42.49 ± 1.2 nm and 44% post calcination. Furthermore, the rGO-HA composites were prepared using ball milling and obtained in the shape of pellets with different ratios of rGO (10, 20, 30, 40, 50% wt.). The mechanical properties have been evaluated through a Universal testing machine. Compared to calcined HAp (cHAp), the strength of variants significantly enhanced with the increased concentration of rGO. The compressive strength of HA-rGO with the ratio of the concentration of 60:40% by weight is a maximum of about 10.39 ± 0.43 MPa. However, the porosity has also been bolstered by increasing the concentration of rGO, which has been evaluated through the liquid displacement method. The mean surface roughness of the composites has also been evaluated from the images through Image J (an image analysis program).
    MeSH terms: Durapatite/chemistry; Compressive Strength
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