Displaying publications 2081 - 2100 of 17217 in total

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  1. A deep neural network-based approach for prediction of mutagenicity of compounds
    Kumar R, Khan FU, Sharma A, Siddiqui MH, Aziz IB, Kamal MA, et al.
    Environ Sci Pollut Res Int, 2021 Sep;28(34):47641-47650.
    PMID: 33895950 DOI: 10.1007/s11356-021-14028-9
    We are exposed to various chemical compounds present in the environment, cosmetics, and drugs almost every day. Mutagenicity is a valuable property that plays a significant role in establishing a chemical compound's safety. Exposure and handling of mutagenic chemicals in the environment pose a high health risk; therefore, identification and screening of these chemicals are essential. Considering the time constraints and the pressure to avoid laboratory animals' use, the shift to alternative methodologies that can establish a rapid and cost-effective detection without undue over-conservation seems critical. In this regard, computational detection and identification of the mutagens in environmental samples like drugs, pesticides, dyes, reagents, wastewater, cosmetics, and other substances is vital. From the last two decades, there have been numerous efforts to develop the prediction models for mutagenicity, and by far, machine learning methods have demonstrated some noteworthy performance and reliability. However, the accuracy of such prediction models has always been one of the major concerns for the researchers working in this area. The mutagenicity prediction models were developed using deep neural network (DNN), support vector machine, k-nearest neighbor, and random forest. The developed classifiers were based on 3039 compounds and validated on 1014 compounds; each of them encoded with 1597 molecular feature vectors. DNN-based prediction model yielded highest prediction accuracy of 92.95% and 83.81% with the training and test data, respectively. The area under the receiver's operating curve and precision-recall curve values were found to be 0.894 and 0.838, respectively. The DNN-based classifier not only fits the data with better performance as compared to traditional machine learning algorithms, viz., support vector machine, k-nearest neighbor, and random forest (with and without feature reduction) but also yields better performance metrics. In current work, we propose a DNN-based model to predict mutagenicity of compounds.
    Matched MeSH terms: Animals
  2. Sublethal effects of phenol on histology of selected organs of freshwater fish Mystus vittatus
    Muthukumaravel K, Vasanthi N, Stalin A, Alam L, Santhanabharathi B, Musthafa MS
    Environ Sci Pollut Res Int, 2021 Mar;28(11):13752-13760.
    PMID: 33191468 DOI: 10.1007/s11356-020-11434-3
    Acute toxicity (96 h LC50) of phenol was analyzed in the cat fish Mystus vittatus in static bio-assay over a 96-h exposure period using probit method. The 24, 48, 72, and 96 h LC50 values (with 95% confidence limits) of phenol for fingerling catfish were found out as 13.98, 13.17, 12.62, and 12.21 mg/l respectively. Investigations pertaining to the histopathological sections have shown high degree of pathological lesions observed in various parts like gill, liver intestine, and kidney of the fish species. Analysis of gill section revealed observable changes in the experimental species such as fusion, malformation at the tip of secondary lamellae, vacuolation, hyperplasia, and epithelial damage. Exposure of phenol showed cytoplasmic vacuolation, tissue damage, and loss of hepatic cell wall in the liver of experimental organism. Lesions of tissue damage at the epithelial site, inflammation, and clumping of adjacent villi made of columnar epithelium have been observed in the intestine of fish, and also the excretory part of the fish kidney revealed various changes like glomerular atrophy, damage of Bowman's capsule, vacuolization, and degeneration of renal epithelium. The current study on histological changes observed in the experimental organisms has thrown light on the current scenario which poses threat and danger to the whole aquatic ecosystem, and this study plays a vital role in assessing the aquatic pollution.
    Matched MeSH terms: Animals
  3. Physicochemical and biological status of Aghlagan river, Iran: effects of seasonal changes and point source pollution
    Asadi Sharif E, Yahyavi B, Bayrami A, Rahim Pouran S, Atazadeh E, Singh R, et al.
    Environ Sci Pollut Res Int, 2021 Mar;28(12):15339-15349.
    PMID: 33236302 DOI: 10.1007/s11356-020-11660-9
    Although the macroinvertebrates have been widely used as bio-indicator for river water quality assessment in developed countries, its application is new in Iran and data on the health status of the most ecologically important rivers in Iran is scarce. The present study aimed at monitoring and assessing the ecological quality of Aghlagan river, northwest of Iran, using integrated physicochemical-biological approaches. A total of 14,423 samplings were carried out from the headwater to downstream sites at four stations (S1, 2, 3, 4) by a Surber sampler (30 cm × 30 cm) from June 2018 to April 2019. The results obtained from macroinvertebrate biotic index revealed that the genera of Gammarus (Amphipoda) and Baetis (Ephemeroptera) were the most abundant in all seasons. The PAST software was applied to analyze the diversity indices (Shannon-Weiner diversity, Evenness, and Simpson indices). Based on the cluster analysis, S3 established the least similarity to other stations. The average frequency of each macroinvertebrate species was determined by one-factor analysis of similarities (ANOSIM). In accordance with canonical correspondence analysis (CCA), temperature and phosphate were found as the dominant factors effecting the macroinvertebrate assemblage and distribution. Moreover, the results obtained from the biological indices concluded very good quality of S4 by Helsinhoff and EPT indices and fair quality using BMWP index. The data on the macrobenthos assemblage and dynamics in the Aghlagan river across a hydraulic gradient provided useful information on water management efforts that assist us to find sustainable solutions for the enhanced quality of the river by balancing environmental and human values.
    Matched MeSH terms: Animals
  4. Selectivity of SO2 and H2S removal by ethanol-treated calcined eggshell at low temperature
    Ahmad W, Sethupathi S, Kanadasan G, Iberahim N
    Environ Sci Pollut Res Int, 2020 Jun;27(17):22065-22080.
    PMID: 32285395 DOI: 10.1007/s11356-020-08671-x
    Eggshell is a food waste produced worldwide in substantial amount with very limited recycling activity. In this study, the potential of ethanol-treated calcined eggshell was tested as sorbent for SO2 and H2S. Three variables were selected in the preparation of sorbents via response surface methodology (RSM), i.e., concentration of ethanol in water (50%, 70%, 90%), reaction temperature (20 °C, 40 °C, 60 °C), and contact time (30, 60, 90 min). Central composite design (CCD) was used to develop a quadratic model to correlate the operating variables with the adsorption capacity. Analysis of variance (ANOVA) was performed to identify the significant factors of the experimental design. It was found that the reaction temperature during the sorbent preparation was the most significant factor. The optimum preparation conditions using RSM were found at 20 °C of reaction temperature with 76.37% of ethanol concentration for 67 min of reaction time. The maximum adsorption capacity for the optimized sorbent was found to be 27.75 mg/g and 9.55 mg/g for SO2 and H2S, respectively. The prepared sorbent was more selective towards SO2 compared with H2S. Moreover, the presence of 40% of relative humidity in the inlet gas further enhanced the adsorption capacity of both gases. The ethanol-treated calcined eggshell was further substantiated by FESEM, BET, FTIR, XRD, and XRF. Results showed potential usage of eggshell as a sorbent for SO2 and H2S gases.
    Matched MeSH terms: Animals
  5. Fulltext Size-age population structure of an endangered and anthropogenically introgressed northern Adriatic population of marble trout (Salmo marmoratus Cuv.): insights for its conservation and sustainable exploitation
    Polgar G, Iaia M, Sala P, Khang TF, Galafassi S, Zaupa S, et al.
    PeerJ, 2023;11:e14991.
    PMID: 36949764 DOI: 10.7717/peerj.14991
    Salmonid species are main actors in the Italian socio-ecological landscape of inland fisheries. We present novel data on the size-age structure of one of the remnant Italian populations of the critically endangered marble trout Salmo marmoratus, which co-occurs with other stocked non-native salmonids in a large glacial river of the Lake Maggiore basin (Northern Italy-Southern Switzerland). Like other Italian native trout populations, the Toce River marble trout population is affected by anthropogenic introgression with the non-native brown trout S. trutta. Our sample includes 579 individuals, mainly collected in the Toce River main channel. We estimated the length-weight relationship, described the population size-age structure, estimated the age-specific growth trajectories, and fit an exponential mortality model. A subset of the sample was also used to measure numerical and biomass density. The estimated asymptotic maximum length is ~105 cm total length (TL). Mean length at first maturity is ~55 cm TL, and mean length at maximum yield per recruit is ~68 cm TL. Approximately 45-70% of the population are estimated to die annually, along with a fishing annual mortality of ~37%, with an exploitation ratio of ~0.5. The frequency distribution of length classes in a sample collected by angling shows that ~80% of the individuals that could be retained according to the current recreational fishing regulations likely never reproduced, and large fish disproportionally contributing to recruitment are fished and retained. We identify possible overfishing risks posed by present regulations, and propose updated harvest-slot length limits to mitigate such risks. More detailed and long-term datasets on this system are needed to more specifically inform the fishery management and monitor the effects of any change in the management strategy on the size-age structure of the marble trout population of the Toce River.
    Matched MeSH terms: Animals
  6. Influence of environmental factors on biology and catch composition of Barbonymus schwanenfeldii in a tropical lake, northern Malaysia: implications for conservation planning
    Rahman MM, Fathi A
    Environ Sci Pollut Res Int, 2022 Feb;29(9):13661-13674.
    PMID: 34590229 DOI: 10.1007/s11356-021-16502-w
    Very little work has determined the relative importance of uncontrolled environmental factors for affecting fish biology, and how these might influence gillnet catches. This study addresses this deficit for an important Southeast Asian cyprinid (Barbonymus schwanenfeldii). Fish were caught monthly for 12 months using gillnets of three different mesh sizes, each of which was deployed in duplicate at the surface of one of three randomly selected sites in Lake Kenyir, Malaysia, concurrent with determining various environmental parameters and the abundance of phytoplankton (chlorophyll-a). Results indicated that growth co-efficient of B. schwanenfeldii was positively influenced by dissolved oxygen and negatively influenced by total inorganic nitrogen, whereas an opposite result was observed in case of the hepatosomatic index of fish. Water turbidity was a limiting factor only for small fish (mean total length: 15.74±1.10 cm). B. schwanenfeldii could best be caught during the period of high phytoplankton abundance or at the location of high phytoplankton density in the water. Water temperature negatively influenced the gillnet catches of the fish. The remaining environmental factors such as water depth, pH, and phosphate had a weak and insignificant influence (P >0.05) on the biology and gillnet catches of fish. The observed results can be very useful for the ecological monitoring and conservation plans for this species in relation to climate change. Furthermore, the utility of the similar data for other species would be useful not only for regional but also for international fishery by optimizing catches considering environmental conditions.
    Matched MeSH terms: Animals
  7. The impact of climate variables on marine fish production: an empirical evidence from Bangladesh based on autoregressive distributed lag (ARDL) approach
    Begum M, Masud MM, Alam L, Mokhtar MB, Amir AA
    Environ Sci Pollut Res Int, 2022 Dec;29(58):87923-87937.
    PMID: 35819668 DOI: 10.1007/s11356-022-21845-z
    Several studies have highlighted the significant impact of climate change on agriculture. However, there have been little empirical enquiries into the impact of climate change on marine fish production, particularly in Bangladesh. Hence, this study aims to investigate the impact of climate change on marine fish production in Bangladesh using data from 1961 to 2019. Data were obtained from the Food and Agriculture Organization, Bangladesh Meteorological Department, the World Development Indicators, and the National Oceanic and Atmospheric Administration. The autoregressive distributed lag (ARDL) model was used to describe the dynamic link between CO2 emissions, average temperature, Sea Surface Temperature (SST), rainfall, sunshine, wind and marine fish production. The ARDL approach to cointegration revealed that SST (β = 0.258), rainfall (β =0.297), and sunshine (β =0.663) significantly influence marine fish production at 1% and 10% levels in the short run and at 1% level in the long run. The results also found that average temperature has a significant negative impact on fish production in both short and long runs. On the other hand, CO2 emissions have a negative impact on marine fish production in the short run. Specifically, for every 1% rise in CO2 emissions, marine fish production will decline by 0.11%. The findings of this study suggest that policymakers formulate better policy frameworks for climate change adaptation and sustainable management of marine fisheries at the national level. Research and development in Bangladesh's fisheries sector should also focus on marine fish species that can resist high sea surface temperatures, CO2 emissions, and average temperatures.
    Matched MeSH terms: Animals
  8. Fulltext Interferon therapy and its association with depressive disorders - A review
    Lai JY, Ho JX, Kow ASF, Liang G, Tham CL, Ho YC, et al.
    Front Immunol, 2023;14:1048592.
    PMID: 36911685 DOI: 10.3389/fimmu.2023.1048592
    Interferons (IFNs) are important in controlling the innate immune response to viral infections. Besides that, studies have found that IFNs also have antimicrobial, antiproliferative/antitumor and immunomodulatory effects. IFNs are divided into Type I, II and III. Type I IFNs, in particular IFN-α, is an approved treatment for hepatitis C. However, patients developed neuropsychological disorders during treatment. IFN-α induces proinflammatory cytokines, indoleamine 2,3-dioxygenase (IDO), oxidative and nitrative stress that intensifies the body's inflammatory response in the treatment of chronic inflammatory disease. The severity of the immune response is related to behavioral changes in both animal models and humans. Reactive oxygen species (ROS) is important for synaptic plasticity and long-term potentiation (LTP) in the hippocampus. However, excess ROS will generate highly reactive free radicals which may lead to neuronal damage and neurodegeneration. The limbic system regulates memory and emotional response, damage of neurons in this region is correlated with mood disorders. Due to the drawbacks of the treatment, often patients will not complete the treatment sessions, and this affects their recovery process. However, with proper management, this could be avoided. This review briefly describes the different types of IFNs and its pharmacological and clinical usages and a focus on IFN-α and its implications on depression.
    Matched MeSH terms: Animals
  9. Fulltext Heterochely and handedness in the orange mud crab Scylla olivacea: implication for future culture practice optimisation
    Rozaimi R, Shu-Chien AC, Wang Y, Sutikno S, Ikhwanuddin M, Shi X, et al.
    PeerJ, 2023;11:e15143.
    PMID: 37033733 DOI: 10.7717/peerj.15143
    Asymmetric body traits in bilateral organisms are common and serve a range of different functions. In crustaceans, specifically among brachyuran crabs, heterochely and handedness in some species are known to aid in behavioural responses such as food acquisition, and sexual and territorial displays. However, the heterochely of the intertidal mud crab genus Scylla is still poorly understood. This study investigated the cheliped morphometric characteristics of orange mud crab Scylla olivacea and the relation of heterochely and handedness to sex. Scylla olivacea is heterochelous, with predominant right-handed (70.2%). Three morphometric variables, i.e., propodus length (PL), propodus depth (PD), and propodus width (PW) were significantly larger in the right cheliped and the estimated handedness based on these three variables were consistent with the presence of molariform teeth. The effect of sex had no influence on the occurrence of heterochely or handedness. The frequency of left-handedness increased with size, especially in males. We postulate that handedness reversal, a phenomenon seen in other crab species when the dominant hand is lost, also occurs in S. olivacea, thereby resulting in a change in left-handedness frequency. The use of chelipeds by males in mate and territorial defenses might provide an explanation for the higher risk of losing a dominant cheliped and thus, higher left-handedness frequency compared to females. Future behavioural research could shed light on the selective forces that affect the handedness distribution in mud crabs. Knowledge on heterochely and handedness of mud crabs could be useful for future development of less aggressive crab populations by claw reversal and the optimisation of limb autotomy techniques.
    Matched MeSH terms: Animals
  10. Characterizing and applying immunoglobulins in snakebite diagnostics: A simple and rapid venom detection assay for four medically important snake species in Southeast Asia
    Lee LP, Tan CH, Khomvilai S, Sitprija V, Chaiyabutr N, Tan KY
    Int J Biol Macromol, 2023 May 01;236:123727.
    PMID: 36863668 DOI: 10.1016/j.ijbiomac.2023.123727
    Snakebite envenoming is a medical emergency requiring urgent and specific treatment. Unfortunately, snakebite diagnostics are scarce, time-consuming and lacking specificity. Hence, this study aimed to develop a simple, quick and specific snakebite diagnostic assay using animal antibodies. Anti-venom horse immunoglobulin G (IgG) and chicken immunoglobulin Y (IgY) were produced against the venoms of four major medically important snake species in Southeast Asia, i.e., the Monocled Cobra (Naja kaouthia), Malayan Krait (Bungarus candidus), Malayan Pit Viper (Calloselasma rhodostoma), and White-lipped Green Pit Viper (Trimeresurus albolabris). Different capture:detection configurations of double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) were constructed using both immunoglobulins, and the horse IgG:IgG-HRP configuration was found to be most selective and sensitive in detecting the corresponding venoms. The method was further streamlined to develop a rapid immunodetection assay, which is able to produce a visual color change within 30 min for discrimination between different snake species. The study shows it is feasible to develop a simple, quick and specific immunodiagnostic assay using horse IgG, which can be derived directly from antisera prepared for antivenom production. The proof-of-concept indicates it is a sustainable and affordable approach in keeping with on-going antivenom manufacturing activities for specific species in the region.
    Matched MeSH terms: Animals
  11. Fulltext Single-cell profile reveals the landscape of cardiac immunity and identifies a cardio-protective Ym-1hi neutrophil in myocardial ischemia-reperfusion injury
    Dong Y, Kang Z, Zhang Z, Zhang Y, Zhou H, Liu Y, et al.
    Sci Bull (Beijing), 2024 Apr 15;69(7):949-967.
    PMID: 38395651 DOI: 10.1016/j.scib.2024.02.003
    Myocardial ischemia-reperfusion injury (MIRI) is a major hindrance to the success of cardiac reperfusion therapy. Although increased neutrophil infiltration is a hallmark of MIRI, the subtypes and alterations of neutrophils in this process remain unclear. Here, we performed single-cell sequencing of cardiac CD45+ cells isolated from the murine myocardium subjected to MIRI at six-time points. We identified diverse types of infiltrating immune cells and their dynamic changes during MIRI. Cardiac neutrophils showed the most immediate response and largest changes and featured with functionally heterogeneous subpopulations, including Ccl3hi Neu and Ym-1hi Neu, which were increased at 6 h and 1 d after reperfusion, respectively. Ym-1hi Neu selectively expressed genes with protective effects and was, therefore, identified as a novel specific type of cardiac cell in the injured heart. Further analysis indicated that neutrophils and their subtypes orchestrated subsequent immune responses in the cardiac tissues, especially instructing the response of macrophages. The abundance of Ym-1hi Neu was closely correlated with the therapeutic efficacy of MIRI when neutrophils were specifically targeted by anti-Lymphocyte antigen 6 complex locus G6D (Ly6G) or anti-Intercellular cell adhesion molecule-1 (ICAM-1) neutralizing antibodies. In addition, a neutrophil subtype with the same phenotype as Ym-1hi Neu was detected in clinical samples and correlated with prognosis. Ym-1 inhibition exacerbated myocardial injury, whereas Ym-1 supplementation significantly ameliorated injury in MIRI mice, which was attributed to the tilt of Ym-1 on the polarization of macrophages toward the repair phenotype in myocardial tissue. Overall, our findings reveal the anti-inflammatory phenotype of Ym-1hi Neu and highlight its critical role in myocardial protection during the early stages of MIRI.
    Matched MeSH terms: Animals
  12. Habitat shapes the gut microbiome diversity of Malayan tigers (Panthera tigris jacksoni) as revealed through metabarcoding 16S rRNA profiling
    Gani M, Mohd-Ridwan AR, Sitam FT, Kamarudin Z, Selamat SS, Awang NMZ, et al.
    World J Microbiol Biotechnol, 2024 Feb 28;40(4):111.
    PMID: 38416247 DOI: 10.1007/s11274-023-03868-x
    The gut microbiome refers to the microorganism community living within the digestive tract. The environment plays a crucial role in shaping the gut microbiome composition of animals. The gut microbiome influences the health and behavior of animals, including the critically endangered Malayan tiger (Panthera tigris jacksoni). However, the gut microbiome composition of Malayan tigers, especially those living in their natural habitats, remains poorly understood. To address this knowledge gap, we used next-generation sequencing DNA metabarcoding techniques to analyze the gut microbiome of wild Malayan tigers using fecal samples collected from their natural habitats and in captivity. Our aim was to determine the gut microbiota composition of the Malayan tiger, considering the different types of habitat environments. The results revealed a diverse microbial community within the gut microbiome of Malayan tigers. The prominent phyla that were observed included Firmicutes, Proteobacteria, Actinobacteriota, Fusobacteriota and Bacteroidota. Beta diversity analysis revealed significant differences in gut microbiome composition of Malayan tigers that inhabited oil palm plantations, in villages and protected areas. Diversity analysis also revealed significant difference in the gut microbiome between wild and captive Malayan tigers. However, the distinctions of gut microbiome between wild and captive alpha diversity did not yield significant differences. The differences in microbiome diversity resulted from the interplay of dietary intake and environmental factors. This information will facilitate the establishment of focused conservation approaches and enhance our understanding of the effect of microbiome composition on Malayan tiger health.
    Matched MeSH terms: Animals
  13. The first record of human infection with Bertiella studeri in Malaya
    Desowitz RS, Wong HJ, Fernando MA
    J Helminthol, 1961;35:207-8.
    PMID: 13885756 DOI: 10.1017/S0022149X00004569
    A six year old child living in Singapore was found to be
    infected with the cestode Bertiella studeri. Apparent cure was affected by use of Dichlorophen.
    Matched MeSH terms: Animals
  14. On the adult morphology of Wuchereria sp. (malayi?) from a monkey (Macaca irus) and from cats in Malaya, and on Wuchereria pahangi n.sp. from a dog and a cat
    BUCKLEY JJ, EDESON JF
    J Helminthol, 1956;30(1):1-20.
    PMID: 13319678
    Matched MeSH terms: Animals
  15. Larvicidal potential of plant-based extracts against dengue vector: A short review
    Noorazlan NAA, Camalxaman SN, Mohamed E, Haron N, Rambely AS, Dom NC, et al.
    Med J Malaysia, 2024 Mar;79(Suppl 1):203-208.
    PMID: 38555906
    INTRODUCTION: Dengue fever, a vector borne disease transmitted primarily by Aedes albopictus and Aedes aegypti mosquitoes, has triggered a significant global resurgence. While many vector control programs depend on the use of chemical insecticides to curb outbreaks, its heavy reliance raises environmental concerns and the risk of insecticide resistance. Alternatively, botanically derived insecticidal agents with larvicidal properties offer an ecofriendlier option. This review aims to analyze scientific reports that described the effectiveness of plant-derived extracts for vector control.

    MATERIALS AND METHODS: A literature search was performed to analyze studies that focused on plant-based extracts used for larvicidal purposes using databases such as Science Direct. Springer, PubMed, and Scopus. The inclusion criteria for publications were larvicidal effects, published in English from the year 2017 and availability of full-text articles. The available literature was further characterized by the value of larvicidal activities of LC50 and LC90 (< 50 ppm), of 22 different parts of plant species from 7 plant families namely Apiaceae, Asteraceae, Lauraceae, Magnoliaceae, Myrtaceae, Piperaceae and Rubiaceae.

    RESULTS: When comparing the values of LC50, 12 plants species (Artemisia vulgaris, Crassocephalum crepidioides, Echinops grijsii, Melaleuca leucadendra, Neolitsea ellipsoidea, Pavetta tomentosa, Piper betle, Piper caninum, Piper Montium, Piper muntabile, Piper ovatum, Tarenna asiatica) showed promising larvicidal efficacies with LC50 < 10 ppm.

    CONCLUSION: This review emphasizes the effective alternatives of plant extracts for the potential production of larvicides. Piper betle extract and chloroform extract of Tarenna asiatica reported the most significant larvicidal activity (LC50 < 1 ppm) against mosquito vectors. Further reviews focusing on the mode of actions of its phytochemically constituents are essential for the future development of potentially significant plant-based larvicides.

    Matched MeSH terms: Animals
  16. Fulltext Social stress-induced serotonin dysfunction activates spexin in male Nile tilapia (Oreochromis Niloticus)
    Lim CH, Soga T, Parhar IS
    Proc Natl Acad Sci U S A, 2023 Jan 17;120(3):e2117547120.
    PMID: 36623187 DOI: 10.1073/pnas.2117547120
    Social disturbance in interpersonal relationships is the primary source of stress in humans. Spexin (SPX, SPX1a in cichlid), an evolutionarily conserved neuropeptide with diverse physiological functions, is up-regulated in the brain during chronic social defeat stress in teleost. On the other hand, repeated exposure to social stress can lead to dysregulation of the monoaminergic system and increase the vulnerability of developing depression. Since dysfunction of the serotonin (5-hydroxytryptamine, 5-HT) system is associated with social stress and the pathophysiology of depression, the present study investigated the regulatory relationship between the central 5-HT system and SPX1a in the male teleost, Nile tilapia (Oreochromis niloticus). To identify stress factors that regulate SPX1a gene expression, cortisol, dexamethasone (DEX), and 5-HT were used to treat tilapia brain primary cultures. Our study shows cortisol and DEX treatment had no effect on SPX1a gene expression, but SPX1a gene expression was down-regulated following 5-HT treatment. Anatomical localization showed a close association between 5-HT immunoreactive projections and SPX1a neurons in the semicircular torus. In addition, 5-HT receptors (5-HT2B) were expressed in SPX1a neurons. SPX1a immunoreactive neurons and SPX1a gene expression were significantly increased in socially defeated tilapia. On the other hand, citalopram (antidepressant, 5-HT antagonist) treatment to socially defeated tilapia normalized SPX1a gene expression to control levels. Taken together, the present study shows that 5-HT is an upstream regulator of SPX1a and that the inhibited 5-HT activates SPX1a during social defeat.
    Matched MeSH terms: Animals
  17. Two centuries of biodiversity discovery and loss in Singapore
    Chisholm RA, Kristensen NP, Rheindt FE, Chong KY, Ascher JS, Lim KKP, et al.
    Proc Natl Acad Sci U S A, 2023 Dec 19;120(51):e2309034120.
    PMID: 38079550 DOI: 10.1073/pnas.2309034120
    There is an urgent need for reliable data on the impacts of deforestation on tropical biodiversity. The city-state of Singapore has one of the most detailed biodiversity records in the tropics, dating back to the turn of the 19th century. In 1819, Singapore was almost entirely covered in primary forest, but this has since been largely cleared. We compiled more than 200 y of records for 10 major taxonomic groups in Singapore (>50,000 individual records; >3,000 species), and we estimated extinction rates using recently developed and novel statistical models that account for "dark extinctions," i.e., extinctions of undiscovered species. The estimated overall extinction rate was 37% (95% CI [31 to 42%]). Extrapolating our Singapore observations to a future business-as-usual deforestation scenario for Southeast Asia suggests that 18% (95% CI [16 to 22%]) of species will be lost regionally by 2100. Our extinction estimates for Singapore and Southeast Asia are a factor of two lower than previous estimates that also attempted to account for dark extinctions. However, we caution that particular groups such as large mammals, forest-dependent birds, orchids, and butterflies are disproportionately vulnerable.
    Matched MeSH terms: Animals
  18. Fulltext Multiclonal human origin and global expansion of an endemic bacterial pathogen of livestock
    Yebra G, Harling-Lee JD, Lycett S, Aarestrup FM, Larsen G, Cavaco LM, et al.
    Proc Natl Acad Sci U S A, 2022 Dec 13;119(50):e2211217119.
    PMID: 36469788 DOI: 10.1073/pnas.2211217119
    Most new pathogens of humans and animals arise via switching events from distinct host species. However, our understanding of the evolutionary and ecological drivers of successful host adaptation, expansion, and dissemination are limited. Staphylococcus aureus is a major bacterial pathogen of humans and a leading cause of mastitis in dairy cows worldwide. Here we trace the evolutionary history of bovine S. aureus using a global dataset of 10,254 S. aureus genomes including 1,896 bovine isolates from 32 countries in 6 continents. We identified 7 major contemporary endemic clones of S. aureus causing bovine mastitis around the world and traced them back to 4 independent host-jump events from humans that occurred up to 2,500 y ago. Individual clones emerged and underwent clonal expansion from the mid-19th to late 20th century coinciding with the commercialization and industrialization of dairy farming, and older lineages have become globally distributed via established cattle trade links. Importantly, we identified lineage-dependent differences in the frequency of host transmission events between humans and cows in both directions revealing high risk clones threatening veterinary and human health. Finally, pangenome network analysis revealed that some bovine S. aureus lineages contained distinct sets of bovine-associated genes, consistent with multiple trajectories to host adaptation via gene acquisition. Taken together, we have dissected the evolutionary history of a major endemic pathogen of livestock providing a comprehensive temporal, geographic, and gene-level perspective of its remarkable success.
    Matched MeSH terms: Animals
  19. Fulltext Necrophilic behaviour in wild stump-tailed macaques (Macaca arctoides)
    Toyoda A, Gonçalves A, Maruhashi T, Malaivijitnond S, Matsuda I
    Sci Rep, 2024 May 13;14(1):10946.
    PMID: 38740882 DOI: 10.1038/s41598-024-61678-z
    Necrophilic behavior (attempted copulation with corpses) has been scarcely reported in non-human primates, especially in the wild. Here is the first case of necrophilic behavior observed in wild stump-tailed macaques in Thailand. Six groups of total N > 460 individuals have been identified and habituated. The corpse of an adult female was found and directly observed for 2 days and by camera trap for 3 days. The cause of death could not be identified, but no prominent physical injury was detected. Within 3 days of the observation, three different males attempted copulation with the corpse. Noteworthy for this observation was that not only males in the group of the dead female but also males from different groups interacted with the corpse. Taken together, these observations suggest that some cues emanating from the corpse coupled with a nonresistant/passive orientation may have triggered these responses in the males. Given that necrophiliac responses have been scarcely reported in non-human primates, our findings provide new insight into these behaviors and to comparative thanatology in general.
    Matched MeSH terms: Animals
  20. Risk of extinction, variability in fish species composition, and factors influencing fish biodiversity in the Malacca Strait
    Alam L, Zolkaply SZ, Sumaila UR, Rusydy I, Kutty AA, Bari MA, et al.
    Environ Sci Pollut Res Int, 2024 Jun;31(29):41355-41369.
    PMID: 37103711 DOI: 10.1007/s11356-023-27101-2
    Fish biodiversity in Malaysia is under pressure due to overexploitation, pollution, and climatic stressors. Nevertheless, the information on fish biodiversity and species vulnerability status is not well documented in the region. Therefore, a study on fish species composition and abundance in the Malacca Strait of Malaysia has been conducted for the purpose of monitoring biodiversity, determining the risk of species extinction, and identifying factors influencing biodiversity distribution. The sampling was conducted based on a random stratified sampling method from the three zones of sampling locations, i.e., estuary, mangrove, and open sea area of Tanjung Karang and Port Klang of Malacca Strait. Higher species diversity was recorded at Tanjung Karang coastal and mangrove areas (H' = 2.71; H' = 1.64) than Port Klang coastal and mangrove areas (H' = 1.50, H' = 0.29), an indication that the Port Klang area is comparatively more vulnerable. The study also explored sampling location, habitat, and IUCN red list as the influencing factors for fish biodiversity. Applying IUCN red list, this study identified one Endangered and one Vulnerable species with the forecasted increasing landing for both species. Our findings suggest the urgent need for the implementation of conservation measures as well as the continuous monitoring of fish biodiversity in the area.
    Matched MeSH terms: Animals
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