Displaying publications 81 - 100 of 145 in total

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  1. Fulltext Managing threatened ungulates in logged-primary forest mosaics in Malaysia
    D MR, Linkie M
    PLoS One, 2020;15(12):e0243932.
    PMID: 33315909 DOI: 10.1371/journal.pone.0243932
    Across the tropics, large-bodied mammals have been affected by selective logging in ways that vary with levels of timber extraction, collateral damage, species-specific traits and secondary effects of hunting, as facilitated by improved access through logging roads. In Peninsular Malaysia, 3.0 million hectares or 61 percent of its Permanent Reserved Forests is officially assigned for commercial selective logging. Understanding how wildlife adapts and uses logged forest is critical for its management and, for threatened species, their conservation. In this study, we quantify the population status of four tropical ungulate species in a large selectively logged forest reserve and an adjacent primary forest protected area. We then conduct finer scale analyses to identify the species-specific factors that determine their occurrence. A combined indirect sign-camera trapping approach with a large sampling effort (2,665 km and 27,780 trap nights surveyed) covering a wide area (560 km2) generated species-specific detection probabilities and site occupancies. Populations of wild boar were widespread across both logged and primary forests, whereas sambar and muntjac occupancy was lower in logged forest (48.4% and 19.2% respectively), with gaur showing no significant difference. Subsequent modelling revealed the importance of conserving lower elevation habitat in both habitat types, particularly <1,000 m asl, for which occupancies of sambar, muntjac and gaur were typically higher. This finding is important because 75 percent (~13,400 km2) of Peninsular Malaysia's Main Range Forest (Banjaran Titiwangsa) is under 1,000 m asl and therefore at risk of being converted to industrial timber plantations, which calls for renewed thinking around forest management planning.
    Matched MeSH terms: Mammals/physiology*
  2. Fulltext Markers for genetic change
    Forcina G, Camacho-Sanchez M, Tuh FYY, Moreno S, Leonard JA
    Heliyon, 2021 Jan;7(1):e05583.
    PMID: 33437884 DOI: 10.1016/j.heliyon.2020.e05583
    Background and aims: Wildlife conservation has focused primarily on species for the last decades. Recently, popular perception and laws have begun to recognize the central importance of genetic diversity in the conservation of biodiversity. How to incorporate genetic diversity in ongoing monitoring and management of wildlife is still an open question.

    Methods: We tested a panel of multiplexed, high-throughput sequenced introns in the small mammal communities of two UNESCO World Heritage Sites on different continents to assess their viability for large-scale monitoring of genetic variability in a spectrum of diverse species. To enhance applicability across other systems, the bioinformatic pipeline for primer design was outlined.

    Results: The number of loci amplified and amplification evenness decreased as phylogenetic distance increased from the reference taxa, yet several loci were still variable across multiple mammal orders.

    Conclusions: Genetic variability found is informative for population genetic analyses and for addressing phylogeographic and phylogenetic questions, illustrated by small mammal examples here.

    Matched MeSH terms: Mammals
  3. Fulltext Maximizing the value of forest restoration for tropical mammals by detecting three-dimensional habitat associations
    Deere NJ, Guillera-Arroita G, Swinfield T, Milodowski DT, Coomes DA, Bernard H, et al.
    Proc Natl Acad Sci U S A, 2020 10 20;117(42):26254-26262.
    PMID: 32989143 DOI: 10.1073/pnas.2001823117
    Tropical forest ecosystems are facing unprecedented levels of degradation, severely compromising habitat suitability for wildlife. Despite the fundamental role biodiversity plays in forest regeneration, identifying and prioritizing degraded forests for restoration or conservation, based on their wildlife value, remains a significant challenge. Efforts to characterize habitat selection are also weakened by simple classifications of human-modified tropical forests as intact vs. degraded, which ignore the influence that three-dimensional (3D) forest structure may have on species distributions. Here, we develop a framework to identify conservation and restoration opportunities across logged forests in Borneo. We couple high-resolution airborne light detection and ranging (LiDAR) and camera trap data to characterize the response of a tropical mammal community to changes in 3D forest structure across a degradation gradient. Mammals were most responsive to covariates that accounted explicitly for the vertical and horizontal characteristics of the forest and actively selected structurally complex environments comprising tall canopies, increased plant area index throughout the vertical column, and the availability of a greater diversity of niches. We show that mammals are sensitive to structural simplification through disturbance, emphasizing the importance of maintaining and enhancing structurally intact forests. By calculating occurrence thresholds of species in response to forest structural change, we identify areas of degraded forest that would provide maximum benefit for multiple high-conservation value species if restored. The study demonstrates the advantages of using LiDAR to map forest structure, rather than relying on overly simplistic classifications of human-modified tropical forests, for prioritizing regions for restoration.
    Matched MeSH terms: Mammals
  4. Medical ecological considerations of a collection of mammals from East Malaysia
    Muul I, Lim Boo Liat
    Southeast Asian J. Trop. Med. Public Health, 1973 Jun;4(2):285-6.
    PMID: 4749096
    Matched MeSH terms: Mammals*
  5. Fulltext Molecular Identification of Giardia duodenalis Isolates from Fars Province, Iran
    Rayani M, Zasmy Unyah N, Hatam G
    Iran J Parasitol, 2014 Mar;9(1):70-8.
    PMID: 25642262
    Giardia duodenalis is one of the most common human intestinal protozoan parasites worldwide and is endemic throughout the world with a vast range of mammalian hosts. The present study aimed to identify the prevalence of G. duodenalis isolates and determine the most common of its assemblages in the patients referring to health centers and hospitals in Fars province, Iran that will be subjected to further molecular investigation.
    Matched MeSH terms: Mammals
  6. Molecular characterization of pathogenic Leptospira sp. in small mammals captured from the human leptospirosis suspected areas of Selangor state, Malaysia
    Azhari NN, Ramli SNA, Joseph N, Philip N, Mustapha NF, Ishak SN, et al.
    Acta Trop, 2018 Dec;188:68-77.
    PMID: 30145261 DOI: 10.1016/j.actatropica.2018.08.020
    Leptospirosis is caused by the spirochetal bacterium Leptospira of which rodents are considered the most important reservoir. This study aims to determine and characterize virulent Leptospira species among rodents and small mammals found in human settlements and recreational spots within the Hulu Langat and Gombak districts of Selangor, Malaysia; regions that frequently report probable human leptospirosis cases. Molecular analysis revealed an overall Leptospira detection rate of 14.3% among the 266 small mammals captured, and the human settlements were found to have the highest number of isolates (15.1%), followed by recreational sites (14.5%). The molecular characterization conducted based on the lipL32, secY genes and MLST revealed that the strains belonged to four different species, including; Leptospira interrogans (29; 76.3%; ST50, ST238, ST243), L. kirschneri (5; 13.15%; ST110), L. borgpetersenii (3; 8%; ST143) and L. weilii (1; 2.63%; ST242). The study revealed genotypes of circulating strains among small mammals in Malaysia, which include Leptospira locus ST110 L. kirschneri, ST 50 L. interrogans, ST143 L. borgpetersenii and ST242 L. weilii. Among the small mammals studied, 17/105 (16.2%) Rattus norvegicus, 7/59 (11.9%) of Rattus rattus, 5/24 (20.8%) of Maxomys whiteheadi, 4/18 (22.2%) of Sundamys muelleri, 2/22 (9%), Tupaia gliss, 2/16 (12.5%) Rattus tiomanicus and 1/4 (25%) of Suncus murinus carried pathogenic leptospires. The data from the present study may imply that, in addition to rodents, other small mammals also serve as maintenance hosts for Leptospira. Hence, much remains unknown about Leptospira maintenance hosts, and there is need for further investigation to ascertain the prevailing serovars of pathogenic Leptospira in Malaysia. This will assist in the development of efficient diagnostic assays with improved microscopic agglutination test (MAT) panels, and in the implementation of suitable prevention and control measures.
    Matched MeSH terms: Mammals
  7. Fulltext Molecular cloning of a functional FADS2 promoter from zebrafish
    Chung, Hung Hui, Azham Zulkharnain
    Journal of Biochemistry, Microbiology and Biotechnology, 2016;4(1):1-6.
    MyJurnal
    The FADS2 catalyzes the first rate-limiting step in the long chain-polyunsaturated fatty acids
    (LC-PUFAs) biosynthesis pathway by converting -linolenic acid and linoleic acid into
    stearidonic acid and -linolenic acid via the -3 and -6 pathways respectively. In mammals,
    PPAR and SREBP-1c have been implicated in the polyunsaturated fatty acids (PUFAs)
    mediated transcriptional activation of FADS2 promoter. However, in zebrafish, not much is
    known regarding the regulation of fads2 transcriptional regulation. Here, in this study, five
    vectors containing different promoter regions were constructed in order to analyse putative
    promoter activities. Through truncation analysis, it was found that the 1.2 kb promoter was able
    to drive luciferase activity to an approximate 40-fold in HepG2 cells. Upon mutagenesis
    analysis, three sites which are the putative NF-Y, SREBP and PPAR binding sites were found
    to be essential in driving the promoter activity. Lastly, the 1.2 kb fads2 promoter was able to
    direct EGFP expression specifically to the yolk syncytial layer (YSL) when transiently
    expressed in microinjected zebrafish embryos.
    Matched MeSH terms: Mammals
  8. Molecular diagnosis and genetic diversity of Cryptosporidium spp. in exotic birds of southwest of Iran
    Jalas M, Tavalla M
    Trop Biomed, 2018 Dec 01;35(4):944-950.
    PMID: 33601843
    Cryptosporidium parasites can infect a wide range of vertebrate hosts including reptiles, mammals, and birds. Due to the zoonotic nature of cryptosporidiosis and its close contact with exotic birds and humans, the present study aimed to determine the prevalence and genetic diversity of Cryptosporidium spp. in exotic birds of southwest of Iran, by the staining and molecular methods. In the present research, 369 stool specimens were randomly collected from exotic birds and stained by modified acid-fast stain using Ziehl-Neelsen method. The slides were examined using light microscopy at a magnification of 100X. Then, the extracted DNA was amplified using the PCR method. Finally, all genotypes and positive samples from PCR assay were sequenced by Bioneer Company (Daejeon, South Korea). Among 369 stool specimens, 25 and 27 cases were found to be positive for Cryptosporidium spp. by the modified Ziehl-Neelsen staining and the PCR methods, respectively. Based on the genotyping, C. avian genotype III and C. meleagridis were detected in 25 and 2 stool samples, respectively. The results revealed a relatively high prevalence of Cryptosporidium spp. in exotic birds in the southwest of Iran. Due to the zoonotic nature of C. meleagridis, these exotic birds can be a significant source of cryptosporidiosis. It is important that high-risk people, including immune-deficient patients, receive correct information about the risk of indirect and direct contact with infected exotic birds.
    Matched MeSH terms: Mammals
  9. Molecular epidemiology of Bartonella species from sympatric mammals collected in urban and rural areas of Punjab, Pakistan
    Rizwan M, Ali S, Javid A, von Fricken ME, Rashid MI
    Acta Trop, 2023 Jul;243:106940.
    PMID: 37160189 DOI: 10.1016/j.actatropica.2023.106940
    Bartonella can infect a variety of mammals including humans and has been detected in the Americas, Europe, Africa, and Asia. Roughly two-thirds of identified Bartonella species are found and maintained in rodent reservoirs, with some of these species linked to human infections. Rodents (N=236) were caught from the Sahiwal division of Punjab, Pakistan and tested for Bartonella using PCR targeting gltA and rpoB genes, followed by sequencing of rpoB-positive samples. Genetic relatedness to other published Bartonella spp. rpoB gene sequences were examined using BLAST and phylogenetic analysis. Overall, 7.62% (18/236) of rodents were positive for both gltA and rpoB fragments. Rattus rattus and R. norvegicus had 7.94% (12/151) and 7.05% (6/85) positivity rates for Bartonella DNA, respectively. Phylogenetic analysis revealed a close relatedness between Bartonella spp. from Pakistan to Bartonella spp. from China, Nepal, and Malaysia. This study is the first reported detection of Bartonella spp. in R. rattus and R. norvegicus from the Sahiwal area of Punjab, Pakistan.
    Matched MeSH terms: Mammals
  10. Fulltext Niches, body sizes, and the disassembly of mammal communities on the Sunda Shelf islands
    Okie JG, Brown JH
    Proc Natl Acad Sci U S A, 2009 Nov 17;106 Suppl 2:19679-84.
    PMID: 19805179 DOI: 10.1073/pnas.0901654106
    The rising sea level at the end of the Pleistocene that created the islands of the Sunda Shelf in Indonesia and Malaysia provides a natural experiment in community disassembly and offers insights into the effects of body size and niches on abundance, distribution, and diversity. Since isolation, terrestrial mammal communities of these islands have been reduced by extinction, with virtually no offsetting colonization. We document three empirical patterns of disassembly, all of which are significantly different from null models of random assembly: (i) a diversity-area relationship: the number of taxa is strongly and positively correlated with island area; (ii) nested subset composition: species that occur on small islands tend to be subsets of more diverse communities inhabiting larger islands; and (iii) body size distributions: species of intermediate body sizes occur on the greatest number of islands, and smaller islands have smaller ranges of body sizes, caused by the absence of species of both very large and extremely small size. These patterns reveal the role of body size and other niche characteristics, such as habitat requirements and trophic status, in the differential susceptibility of taxa to extinction.
    Matched MeSH terms: Mammals/physiology*
  11. Fulltext Novel method for gelatin extraction of various local fish using High Pressure Processing (HPP)
    Jamal, P., Jaswir, I., Yusof, N., Jami, M.S.
    International Food Research Journal, 2017;24(101):533-539.
    MyJurnal
    Gelatin from fish skin is known to be an alternative source for mammalian gelatin. However, it has weaker properties compared to bovine and porcine gelatin, which limits its use in the industry. The conventional method for fish gelatin extraction requires long production time and could cause serious water pollution and chemical treatments are often being used to enhance the yield of fish gelatin and its properties but it may affect the amino acid content of the gelatin. In this regard, High-Pressure Processing (HPP) is a novel method suggested for fish gelatin extraction. The HPP method is classified as green technology as it requires low electricity throughout the process. This study will discuss the impact of HPP the technique gelatin extracted from fish skin. Skins from four types of fish, namely red tilapia (Oreochromis niloticus), black tilapia (Oreochromis mossambicus), grouper (Epinephelus areolatus) and threadfin bream (Nemipterus tambuloides), were used. High pressure was applied at either pretreatment in citric acid solution or during thermal extraction; and the pressure was maintained at 250 MPa with pressure holding time of 10 minutes and 18 hours of water extraction. Gelatin extract from traditional acid-base method was prepared as a standard for comparison. The study found that there was an increment in the yield of gelatin and the concentration of gelatin extract, and the pre-treatment time was also reduced.
    Matched MeSH terms: Mammals
  12. Fulltext Nuanced contribution of gut microbiome in the early brain development of mice
    Yeo XY, Chae WR, Lee HU, Bae HG, Pettersson S, Grandjean J, et al.
    Gut Microbes, 2023 Dec;15(2):2283911.
    PMID: 38010368 DOI: 10.1080/19490976.2023.2283911
    The complex symbiotic relationship between the mammalian body and gut microbiome plays a critical role in the health outcomes of offspring later in life. The gut microbiome modulates virtually all physiological functions through direct or indirect interactions to maintain physiological homeostasis. Previous studies indicate a link between maternal/early-life gut microbiome, brain development, and behavioral outcomes relating to social cognition. Here we present direct evidence of the role of the gut microbiome in brain development. Through magnetic resonance imaging (MRI), we investigated the impact of the gut microbiome on brain organization and structure using germ-free (GF) mice and conventionalized mice, with the gut microbiome reintroduced after weaning. We found broad changes in brain volume in GF mice that persist despite the reintroduction of gut microbes at weaning. These data suggest a direct link between the maternal gut or early-postnatal microbe and their impact on brain developmental programming.
    Matched MeSH terms: Mammals
  13. Oil palm plantations fail to support mammal diversity
    Yue S, Brodie JF, Zipkin EF, Bernard H
    Ecol Appl, 2015 Dec;25(8):2285-92.
    PMID: 26910955
    Agricultural expansion is the largest threat to global biodiversity. In particular, the rapid spread of tree plantations is a primary driver of deforestation in hyperdiverse tropical regions. Plantations tend to support considerably lower biodiversity than native forest, but it remains unclear whether plantation traits affect their ability to sustain native wildlife populations, particularly for threatened taxa. If animal diversity varies across plantations with different characteristics, these traits could be manipulated to make plantations more "wildlife friendly." The degree to which plantations create edge effects that degrade habitat quality in adjacent forest also remains unclear, limiting our ability to predict wildlife persistence in mixed-use landscapes. We used systematic camera trapping to investigate mammal occurrence and diversity in oil palm plantations and adjacent forest in Sabah, Malaysian Borneo. Mammals within plantations were largely constrained to locations near native forest; the occurrence of most species and overall species richness declined abruptly with decreasing forest proximity from an estimated 14 species at the forest ecotone to -1 species 2 km into the plantation. Neither tree height nor canopy cover within plantations strongly affected mammal diversity or occurrence, suggesting that manipulating tree spacing or planting cycles might not make plantations more wildlife friendly. Plantations did not appear to generate strong edge effects; mammal richness within forest remained high and consistent up to the plantation ecotone. Our results suggest that land-sparing strategies, as opposed to efforts to make plantations more wildlife-friendly, are required for regional wildlife conservation in biodiverse tropical ecosystems.
    Matched MeSH terms: Mammals/classification*
  14. Oncolytic Reoviruses: Can These Emerging Zoonotic Reoviruses Be Tamed and Utilized?
    Siew ZY, Loh A, Segeran S, Leong PP, Voon K
    DNA Cell Biol, 2023 Jun;42(6):289-304.
    PMID: 37015068 DOI: 10.1089/dna.2022.0561
    Orthoreovirus is a nonenveloped double-stranded RNA virus under the Reoviridae family. This group of viruses, especially mammalian orthoreovirus (MRV), are reported with great therapeutic values due to their oncolytic effects. In this review, the life cycle and oncolytic effect of MRV and a few emerging reoviruses were summarized. This article also highlights the challenges and strategies of utilizing MRV and the emerging reoviruses, avian orthoreovirus (ARV) and pteropine orthoreovirus (PRV), as oncolytic viruses (OVs). Besides, the emergence of potential ARV and PRV as OVs were discussed in comparison to MRV. Finally, the risk of reovirus as zoonosis or reverse zoonosis (zooanthroponosis) were debated, and concerns were raised in this article, which warrant continue surveillance of reovirus (MRV, ARV, and PRV) in animals, humans, and the environment.
    Matched MeSH terms: Mammals
  15. Fulltext Oral myiasis : case report
    Ramli R, Abd Rahman R
    Malays J Med Sci, 2002 Jul;9(2):47-50.
    PMID: 22844224
    Myiasis occurs when living tissues of mammals are invaded by eggs or larvae of flies, mainly from the order of Diptera. Most of the previousty reported cases are in the tropics and they were usually associated with inadequate personal hygiene, sometimes with poor manual dexterity. This report describes two cases of oral myiasis in cerebral palsy patients in Seremban General Hospital, Malaysia. This article also discusses the therapeutic property of maggots and highlights the importance of oral health care in the special needs patients.
    Matched MeSH terms: Mammals
  16. Pangolin genomes and the evolution of mammalian scales and immunity
    Choo SW, Rayko M, Tan TK, Hari R, Komissarov A, Wee WY, et al.
    Genome Res, 2016 10;26(10):1312-1322.
    PMID: 27510566
    Pangolins, unique mammals with scales over most of their body, no teeth, poor vision, and an acute olfactory system, comprise the only placental order (Pholidota) without a whole-genome map. To investigate pangolin biology and evolution, we developed genome assemblies of the Malayan (Manis javanica) and Chinese (M. pentadactyla) pangolins. Strikingly, we found that interferon epsilon (IFNE), exclusively expressed in epithelial cells and important in skin and mucosal immunity, is pseudogenized in all African and Asian pangolin species that we examined, perhaps impacting resistance to infection. We propose that scale development was an innovation that provided protection against injuries or stress and reduced pangolin vulnerability to infection. Further evidence of specialized adaptations was evident from positively selected genes involving immunity-related pathways, inflammation, energy storage and metabolism, muscular and nervous systems, and scale/hair development. Olfactory receptor gene families are significantly expanded in pangolins, reflecting their well-developed olfaction system. This study provides insights into mammalian adaptation and functional diversification, new research tools and questions, and perhaps a new natural IFNE-deficient animal model for studying mammalian immunity.
    Matched MeSH terms: Mammals/anatomy & histology; Mammals/classification; Mammals/genetics*; Mammals/immunology
  17. Fulltext Pax6 mutant cerebral organoids partially recapitulate phenotypes of Pax6 mutant mouse strains
    Ferdaos N, Lowell S, Mason JO
    PLoS One, 2022;17(11):e0278147.
    PMID: 36441708 DOI: 10.1371/journal.pone.0278147
    Cerebral organoids show great promise as tools to unravel the complex mechanisms by which the mammalian brain develops during embryogenesis. We generated mouse cerebral organoids harbouring constitutive or conditional mutations in Pax6, which encodes a transcription factor with multiple important roles in brain development. By comparing the phenotypes of mutant organoids with the well-described phenotypes of Pax6 mutant mouse embryos, we evaluated the extent to which cerebral organoids reproduce phenotypes previously described in vivo. Organoids lacking Pax6 showed multiple phenotypes associated with its activity in mice, including precocious neural differentiation, altered cell cycle and an increase in abventricular mitoses. Neural progenitors in both Pax6 mutant and wild type control organoids cycled more slowly than their in vivo counterparts, but nonetheless we were able to identify clear changes to cell cycle attributable to the absence of Pax6. Our findings support the value of cerebral organoids as tools to explore mechanisms of brain development, complementing the use of mouse models.
    Matched MeSH terms: Mammals
  18. Fulltext Penentuan kandungan makronutrien dalam tiga jenis kuih manis tempatan: pengiraan berbanding analisis
    Hasnah Haron, Nurul Hidayah Aminudin, Nik Shanita Safii, Hazila Khalid
    Jurnal Sains Kesihatan Malaysia, 2013;11(1):19-24.
    MyJurnal
    Kajian ini bertujuan untuk membandingkan kandungan makronutrien dalam tiga jenis kuih manis tempatan iaitu kuih seri muka (SM), kuih bakar (B) dan kuih wajik (W) yang mana resepinya telah dibentuk secara pengiraan nutrien yang berdasarkan Jadual Komposisi Makanan Malaysia (JKMMM) dengan kaedah analisis secara proksimat. Penentuan kandungan makronutrien secara spesifik ditentukan menggunakan kaedah analisis proksimat manakala penentuan tenaga dan karbohidrat total dijalankan melalui pengiraan. Hasil analisis proksimat menunjukkan W mengandungi karbohidrat total tertinggi (61.5 ± 1.6%) secara signifikan (p < 0.05), berbanding B (39.3 ± 1.5%) dan SM (38.7 ± 1.5%). SM mempunyai kandungan air yang lebih tinggi (46.7 ± 1.6%) secara signifikan (p < 0.05) berbanding B (42.5 ± 6.6 %) dan W (30.2 ± 0.4%). B mengandungi kandungan protein tertinggi (6.1 ± 0.9%) secara signifikan berbanding dengan W (3.0 ± 0.3%). Tiada perbezaan yang signifikan bagi kandungan lemak di antara B (12.8 ± 1.8%), SM (9.9 ± 0.2%) dan W (8.2 ± 2.6%). Jumlah kalori untuk W adalah tertinggi (332 kcal/100g) diikuti oleh B (299 kcal/100g) dan SM (262 kcal/100g). Secara umumnya, nilai kandungan makronutrien dari analisis proksimat adalah lebih rendah berbanding secara pengiraan kandungan makronutrien menggunakan JKMMM. Ini disebabkan pengiraan berdasarkan JKMMM adalah berdasarkan bahan mentah manakala analisis proksimat berdasarkan sampel kuih yang telah disediakan.


    Matched MeSH terms: Mammals
  19. Phage N15-Based Vectors for Gene Cloning and Expression in Bacteria and Mammalian Cells
    Wong YC, Ng AWR, Chen Q, Liew PS, Lee CW, Sim EUH, et al.
    ACS Synth Biol, 2023 Apr 21;12(4):909-921.
    PMID: 37026178 DOI: 10.1021/acssynbio.2c00580
    Bacteriophage N15 is the first virus known to deliver linear prophage into Escherichia coli. During its lysogenic cycle, N15 protelomerase (TelN) resolves its telomerase occupancy site (tos) into hairpin telomeres. This protects the N15 prophage from bacterial exonuclease degradation, enabling it to stably replicate as a linear plasmid in E. coli. Interestingly, purely proteinaceous TelN can retain phage DNA linearization and hairpin formation without involving host- or phage-derived intermediates or cofactors in the heterologous environment. This unique feature has led to the advent of synthetic linear DNA vector systems derived from the TelN-tos module for the genetic engineering of bacterial and mammalian cells. This review will focus on the development and advantages of N15-based novel cloning and expression vectors in the bacterial and mammalian environments. To date, N15 is the most widely exploited molecular tool for the development of linear vector systems, especially the production of therapeutically useful miniDNA vectors without a bacterial backbone. Compared to typical circular plasmids, linear N15-based plasmids display remarkable cloning fidelity in propagating unstable repetitive DNA sequences and large genomic fragments. Additionally, TelN-linearized vectors with the relevant origin of replication can replicate extrachromosomally and retain transgenes functionality in bacterial and mammalian cells without compromising host cell viability. Currently, this DNA linearization system has shown robust results in the development of gene delivery vehicles, DNA vaccines and engineering mammalian cells against infectious diseases or cancers, highlighting its multifaceted importance in genetic studies and gene medicine.
    Matched MeSH terms: Mammals/genetics
  20. Fulltext Phytosterols activating nuclear receptors are involving in steroid hormone-dependent cancers: Myth or fact?
    Bakrim S, El Omari N, Khan EJ, Khalid A, Abdalla AN, Chook JB, et al.
    Biomed Pharmacother, 2023 Dec 31;169:115783.
    PMID: 37944439 DOI: 10.1016/j.biopha.2023.115783
    Nuclear receptors (NRs) represent intracellular proteins that function as a signaling network of transcriptional factors to control genes in response to a variety of environmental, dietary, and hormonal stimulations or serve as orphan receptors lacking a recognized ligand. They also play an essential role in normal development, metabolism, cell growth, cell division, physiology, reproduction, and homeostasis and function as biological markers for tumor subclassification and as targets for hormone therapy. NRs, including steroid hormone receptors (SHRs), have been studied as tools to examine the fundamentals of transcriptional regulation within the development of mammals and human physiology, in addition to their links to disturbances. In this regard, it is widely recognized that aberrant NR signaling is responsible for the pathological growth of hormone-dependent tumors in response to SHRs dysregulation and consequently represents a potential therapeutic candidate in a range of diseases, as in the case of prostate cancer and breast cancer. On the other hand, phytosterols are a group of plant-derived compounds that act directly as ligands for NRs and have proven their efficacy in the management of diabetes, heart diseases, and cancers. However, these plants are not suggested in cases of hormone-dependent cancer since a certain group of plants contains molecules with a chemical structure similar to that of estrogens, which are known as phytoestrogens or estrogen-like compounds, such as lignans, coumestans, and isoflavones. Therefore, it remains an open and controversial debate regarding whether consuming a phytosterol-rich diet and adopting a vegetarian lifestyle like the Mediterranean diet may increase the risk of developing steroid hormone-dependent cancers by constitutively activating SHRs and thereby leading to tumor transformation. Overall, the purpose of this review is to better understand the relevant mechanistic pathways and explore epidemiological investigations in order to establish that phytosterols may contribute to the activation of NRs as cancer drivers in hormone-dependent cancers.
    Matched MeSH terms: Mammals
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