Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 370
Filtrar
1.
Sci Rep ; 14(1): 17030, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39043989

RESUMO

Terahertz (THz) spectral region from 0.1 to 3 THz is envisaged to hold immense potential in the next generation of wireless technologies. Recently, research has focused on this terahertz gap, because of its unprecedented channel capacities. At the physical layer, the design complexities and fabrication of THz devices, especially antennas are the prime bottlenecks to realize its full potential. This article introduces a cost-effective, easy-to-fabricate, and reproducible sub-THz antenna design based on a single-layer planar printed circuit board technology. The antenna incorporates carefully designed quasi-cross slots and applied machine learning-assisted global optimization techniques to achieve the desired performance metrics. The antenna performance is elucidated through numerical simulations and verified through a rigorous in-house THz experimental framework around 100-110 GHz. The proposed antenna offers a peak gain of 13.90 dBi with less than 1 dB variation within the entire band of 100-110 GHz. The antenna holds the potential to achieve terabits per second data rates and futuristic high-resolution short-range THz imaging applications.

2.
BMJ Open ; 14(7): e084581, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38960457

RESUMO

OBJECTIVES: Develop and validate short and rapid forms of the 36-item Menstrual Practice Needs Scale (MPNS-36). DESIGN: Item reduction prioritised content validity and was informed by cognitive interviews with schoolgirls in Bangladesh, performance of scale items in past research and stakeholder feedback. The original MPNS-36 was revalidated, and short and rapid forms tested in a cross-sectional survey. This was followed by further tests of dimensionality, internal consistency and validity in multiple cross-sectional surveys. SETTING AND PARTICIPANTS: Short form (MPNS-SF) and rapid form (MPNS-R) measures were developed in a survey of 313 menstruating girls (mean age=13.51) in Khulna, Bangladesh. They were further tested in the baseline survey of the Adolescent Menstrual Experiences and Health Cohort, in Khulna, Bangladesh (891 menstruating girls, mean age=12.40); and the dataset from the MPNS-36 development in Soroti, Uganda (538 menstruating girls, mean age=14.49). RESULTS: The 18-item short form reflects the six original subscales, with the four core subscales demonstrating good fit in all three samples (Khulna pilot: root mean square error of approximation (RMSEA)=0.064, 90% CI 0.043 to 0.084, Comparative Fit Index (CFI)=0.94, Tucker-Lewis Index (TLI)=0.92. Cohort baseline: RMSEA=0.050, 90% CI 0.039 to 0.062, CFI=0.96, TLI=0.95. Uganda: RMSEA=0.039, 90% CI 0.028 to 0.050, CFI=0.95, TLI=0.94). The 9-item rapid form captures diverse needs. A two-factor structure was the most appropriate but fell short of adequate fit (Khulna pilot: RMSEA=0.092, 90% CI 0.000 to 0.158, CFI=0.93, TLI=0.89). Hypothesised associations between the MPNS scores and other constructs were comparable between the MPNS-36 and MPNS-SF in all populations, and replicated, with attenuation, in the MPNS-R. Internal consistency remained acceptable. CONCLUSIONS: The MPNS-SF offers a reliable and valid measure of adolescent girls' menstrual hygiene experience while reducing participant burden, to support implementation and improve measurement in menstrual health research. The MPNS-R provides a brief measure with poorer structural validity, suited to short surveys and including menstrual health within broader research topics.


Assuntos
Menstruação , Psicometria , Humanos , Feminino , Bangladesh , Estudos Transversais , Uganda , Adolescente , Reprodutibilidade dos Testes , Inquéritos e Questionários , Criança , Avaliação das Necessidades
3.
Planta Med ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39079700

RESUMO

The present study endeavored to design and develop a self-nanoemulsifying drug delivery system to improve the solubility and dermatological absorption of curcumin and naringin. Curcumin and naringin-loaded self-nanoemulsifying drug delivery system formulations were developed using aqueous phase titration. Phase diagrams were used to pinpoint the self-nanoemulsifying drug delivery system zones. Tween 80 and Labrasol (surfactants), Transcutol (cosurfactant), and cinnamon oil were chosen from a large pool of surfactants, cosurfactants, and oils based on their solubility and greatest nano-emulsion region. Fourier transform infrared spectroscopy, zeta sizer, and atomic force microscopy were used to characterize the optimized formulations and test for dilution and thermodynamic stability. The optimized curcumin-naringin-self-nanoemulsifying drug delivery system demonstrated the following characteristics: polydispersity index (0.412 ± 0.03), % transmittance (97%), particle size (212.5 ± 05 nm), zeta potential (- 25.7 ± 1.80 mV) and having a smooth and spherical droplet shape, as shown by atomic force microscopy. The ability of their combined formulation to cure wounds was tested in comparison to pure curcumin suspension, empty self-nanoemulsifying drug delivery system, and standard fusidic acid. Upon topical administration, the optimized curcumin-naringin-self-nanoemulsifying drug delivery system demonstrated significant wound healing activity in comparison with a pure curcumin suspension, empty self-nanoemulsifying drug delivery system, and standard fusidic acid. Based upon this result, we assume that skin penetration was increased by using the optimized curcumin-naringin-self-nanoemulsifying drug delivery system with enhanced solubility.

4.
Sci Rep ; 14(1): 10904, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740859

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis, ranks among the top causes of global human mortality, as reported by the World Health Organization's 2022 TB report. The prevalence of M. tuberculosis strains that are multiple and extensive-drug resistant represents a significant barrier to TB eradication. Fortunately, having many completely sequenced M. tuberculosis genomes available has made it possible to investigate the species pangenome, conduct a pan-phylogenetic investigation, and find potential new drug targets. The 442 complete genome dataset was used to estimate the pangenome of M. tuberculosis. This study involved phylogenomic classification and in-depth analyses. Sequential filters were applied to the conserved core genome containing 2754 proteins. These filters assessed non-human homology, virulence, essentiality, physiochemical properties, and pathway analysis. Through these intensive filtering approaches, promising broad-spectrum therapeutic targets were identified. These targets were docked with FDA-approved compounds readily available on the ZINC database. Selected highly ranked ligands with inhibitory potential include dihydroergotamine and abiraterone acetate. The effectiveness of the ligands has been supported by molecular dynamics simulation of the ligand-protein complexes, instilling optimism that the identified lead compounds may serve as a robust basis for the development of safe and efficient drugs for TB treatment, subject to further lead optimization and subsequent experimental validation.


Assuntos
Antituberculosos , Desenho de Fármacos , Mycobacterium tuberculosis , Proteômica , Tuberculose , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Antituberculosos/farmacologia , Humanos , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Proteômica/métodos , Genoma Bacteriano , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Filogenia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Genômica/métodos
5.
Naunyn Schmiedebergs Arch Pharmacol ; 397(8): 5617-5630, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38619588

RESUMO

MiRNAs (microRNAs) constitute a group of diminutive molecules of non-coding RNA intricately involved in regulating gene expression. This regulation is primarily accomplished through the binding of miRNAs to complementary sequences situated in the 3'-UTR of the messenger RNA (mRNA) target; as a result, they are degraded or repressed. The multifaceted biogenesis of miRNAs is characterized by a meticulously orchestrated sequence of events encompassing transcription, processing, transportation, and decay. Colorectal cancer stands as a pervasive and formidable ailment, afflicting millions across the globe. Colorectal cancer is not well diagnosed early, and metastasis rates are high, which results in low survival rates in advanced stages. The genesis and progression of colorectal cancer are subject to the influence of genetic and epigenetic factors, among which miRNAs play a pivotal role. When it comes to colorectal cancer, miRNAs have a dual character, depending on the genes they target, functioning as either tumor suppressors or oncogenes and the prevailing cellular milieu. Their impact extends to modulating critical facets of colorectal cancer pathogenesis, including proliferation, angiogenesis, apoptosis, chemoresistance, and radiotherapy response. The discernible potential of miRNAs which are used as biomarkers to diagnose colorectal cancer, prognosis, and treatment response has come to the forefront. Notably, miRNAs are easily found and detected readily in a variety of biological fluids, including saliva, blood, urine, and feces. This prominence is attributed to the inherent advantages of miRNAs over conventional biomarkers, including heightened stability, specificity, sensitivity, and accessibility. Various investigations have pinpointed miRNA signatures or panels capable of differentiating colorectal cancer patients from their healthy counterparts, predicting colorectal cancer stage and survival, and monitoring colorectal cancer recurrence and therapy response. Although there has been research on miRNAs in various diseases, there has been less research on miRNAs in cancer. Moreover, updated results of preclinical and clinical studies on miRNA biomarkers and drugs are required. Nevertheless, the integration of miRNAs as biomarkers for colorectal cancer is not devoid of challenges and limitations. These encompass the heterogeneity prevalent among colorectal cancer subtypes and stages, the variability in miRNA expression across different tissues and individuals, the absence of standardized methodologies for miRNA detection and quantification, and the imperative for validation through extensive clinical trials. Consequently, further research is imperative to conclusively establish the clinical utility and reliability of miRNAs as colorectal cancer biomarkers. MiR-21 demonstrates carcinogenic characteristics by targeting several tumor suppressor genes, which encourages cell division, invasion, and metastasis. On the other hand, by controlling the Wnt/ß-catenin pathway, the tumor suppressor miRNA miR-34a prevents CRC cell proliferation, migration, and invasion. Furthermore, in colorectal cancer, the miR-200 family increases chemotherapy sensitivity while suppressing epithelial-mesenchymal transition (EMT). As an oncogene, the miR-17-92 cluster targets elements of the TGF-ß signaling pathway to encourage the growth of CRC cells. Finally, miR-143/145, which is downregulated in CRC, influences apoptosis and the progression of the cell cycle. These miRNAs affect pathways like Wnt, TGF-ß, PI3K-AKT, MAPK, and EMT, making them potential clinical biomarkers and therapeutic targets. This review summarizes recent research related to miRNAs, their role in tumor progression and metastasis, and their potential as biomarkers and therapeutic targets in colorectal cancer. In addition, we combined miRNAs' roles in tumorigenesis and development with the therapy of CRC patients, leading to novel perspectives on colorectal cancer diagnosis and treatment.


Assuntos
Apoptose , Proliferação de Células , Neoplasias Colorretais , Resistencia a Medicamentos Antineoplásicos , MicroRNAs , Neovascularização Patológica , Animais , Humanos , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Apoptose/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Neovascularização Patológica/genética
6.
Vet Parasitol ; 328: 110176, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38603926

RESUMO

Pituitary pars intermedia dysfunction (PPID) is the most common endocrine disorder of older horses. Immune dysfunction in horses with PPID could increase susceptibility to infectious diseases, including strongyle infections; however, few data are available. The aim of this study was to determine if horses with PPID had increased strongyle faecal egg counts (FEC) compared with control horses, over a fourteen-week period in Victoria, Australia. Clinical signs and plasma adrenocorticotropic hormone (ACTH) concentrations were used to categorise horses into PPID (n=14) or control (n=31) groups. Faecal samples were collected for FEC determination prior to anthelmintic treatment, and fortnightly post-treatment for each horse. Generalised linear mixed modelling, using a gamma distribution, was used to compare differences between groups in the repeated measures study. The confounding variable of age was controlled for as a fixed effect. Following anthelmintic treatment, mean FEC was greater for the PPID group compared to the control group on day 56 (405 ± 756 eggs per gram [EPG] vs 40 ± 85 EPG, p=0.05) and day 70 (753 ±1598 EPG vs 82 ±141 EPG, p=0.04). There were no differences in mean FEC between groups on days 84 and 98. Cumulative FEC (day 14 to day 98) was significantly greater for the PPID horses than control horses (2118 ± 4016 EPG vs 798 ± 768 EPG, p<0.0001). Group egg reappearance period was shorter for PPID horses (day 56 post-anthelmintic treatment) compared to control horses (day 70) and 30% of the PPID horses reached a FEC threshold of >200 EPG on day 42, compared to 0% of control horses (p=0.02). These results suggest that the rate of a re-established patent infection between groups could be different due to a comprised immune response in PPID horses or differences in the host-parasite relationship regarding encysted stage larvae. However, despite differences between groups, some horses with PPID consistently had no detectable or low FEC (<200 EPG) during the study period. These findings highlight the importance of individual FEC monitoring to determine if anthelmintic treatment is required, in line with sustainable parasite management practices.


Assuntos
Anti-Helmínticos , Fezes , Contagem de Ovos de Parasitas , Doenças da Hipófise , Adeno-Hipófise Parte Intermédia , Infecções Equinas por Strongyloidea , Animais , Cavalos , Contagem de Ovos de Parasitas/veterinária , Fezes/parasitologia , Doenças da Hipófise/veterinária , Doenças da Hipófise/parasitologia , Anti-Helmínticos/uso terapêutico , Feminino , Infecções Equinas por Strongyloidea/parasitologia , Infecções Equinas por Strongyloidea/tratamento farmacológico , Masculino , Doenças dos Cavalos/parasitologia , Doenças dos Cavalos/tratamento farmacológico , Hormônio Adrenocorticotrópico/sangue , Vitória
7.
Food Chem ; 449: 139256, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38636286

RESUMO

In this report, we firstly synthesized nitro calix [4] resorcinarene compound (referred as KA30) and characterized it though proton (1H) nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry (ESI-MS) and Fourier Transform Infra-red (FTIR) spectroscopy. KA30 was applied as functionalizing agent for the formation of silver nanoparticles (KA30-AgNPs). These NPs were confirmed as highly selective and extremely sensitive colorimetric sensor for ultra-low level detection of emamectin (EMA) as a novel report. Significant aspect of the sensor is its unique detection range between 0.0005 and 29.5 µM via color change from yellow to colorless with hypochromic-bathochromic shift exhibiting limit of detection (LOD) and limit of quantification (LOQ) as 0.12 nM and 0.4 nM respectively. The sensor was applied to colorimetrically and optically detect EMA in real samples of serum, urine and food. The sensor was further allied with smartphone for real-time, and on-site detection of EMA and results were validated through UPLC.


Assuntos
Colorimetria , Contaminação de Alimentos , Ivermectina , Nanopartículas Metálicas , Prata , Smartphone , Prata/química , Colorimetria/métodos , Nanopartículas Metálicas/química , Contaminação de Alimentos/análise , Ivermectina/análogos & derivados , Ivermectina/química , Ivermectina/análise , Limite de Detecção , Calixarenos/química , Humanos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
8.
BMJ Open ; 14(4): e079451, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604626

RESUMO

BACKGROUND: Menstrual health is essential for gender equity and the well-being of women and girls. Qualitative research has described the burden of poor menstrual health on health and education; however, these impacts have not been quantified, curtailing investment. The Adolescent Menstrual Experiences and Health Cohort (AMEHC) Study aims to describe menstrual health and its trajectories across adolescence, and quantify the relationships between menstrual health and girls' health and education in Khulna, Bangladesh. METHODS AND ANALYSIS: AMEHC is a prospective longitudinal cohort of 2016 adolescent girls recruited at the commencement of class 6 (secondary school, mean age=12) across 101 schools selected through a proportional random sampling approach. Each year, the cohort will be asked to complete a survey capturing (1) girls' menstrual health and experiences, (2) support for menstrual health, and (3) health and education outcomes. Survey questions were refined through qualitative research, cognitive interviews and pilot survey in the year preceding the cohort. Girls' guardians will be surveyed at baseline and wave 2 to capture their perspectives and household demographics. Annual assessments will capture schools' water, sanitation and hygiene, and support for menstruation and collect data on participants' education, including school attendance and performance (in maths, literacy). Cohort enrolment and baseline survey commenced in February 2023. Follow-up waves are scheduled for 2024, 2025 and 2026, with plans for extension. A nested subcohort will follow 406 post-menarche girls at 2-month intervals throughout 2023 (May, August, October) to describe changes across menstrual periods. This protocol outlines a priori hypotheses regarding the impacts of menstrual health to be tested through the cohort. ETHICS AND DISSEMINATION: AMEHC has ethical approval from the Alfred Hospital Ethics Committee (369/22) and BRAC James P Grant School of Public Health Institutional Review Board (IRB-06 July 22-024). Study materials and outputs will be available open access through peer-reviewed publication and study web pages.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Menstruação , Feminino , Adolescente , Humanos , Criança , Menstruação/psicologia , Bangladesh/epidemiologia , Estudos Prospectivos , Menarca
9.
Int J Parasitol Drugs Drug Resist ; 25: 100534, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38554597

RESUMO

Infections and diseases caused by parasitic nematodes have a major adverse impact on the health and productivity of animals and humans worldwide. The control of these parasites often relies heavily on the treatment with commercially available chemical compounds (anthelmintics). However, the excessive or uncontrolled use of these compounds in livestock animals has led to major challenges linked to drug resistance in nematodes. Therefore, there is a need to develop new anthelmintics with novel mechanism(s) of action. Recently, we identified a small molecule, designated UMW-9729, with nematocidal activity against the free-living model organism Caenorhabditis elegans. Here, we evaluated UMW-9729's potential as an anthelmintic in a structure-activity relationship (SAR) study in C. elegans and the highly pathogenic, blood-feeding Haemonchus contortus (barber's pole worm), and explored the compound-target relationship using thermal proteome profiling (TPP). First, we synthesised and tested 25 analogues of UMW-9729 for their nematocidal activity in both H. contortus (larvae and adults) and C. elegans (young adults), establishing a preliminary nematocidal pharmacophore for both species. We identified several compounds with marked activity against either H. contortus or C. elegans which had greater efficacy than UMW-9729, and found a significant divergence in compound bioactivity between these two nematode species. We also identified a UMW-9729 analogue, designated 25, that moderately inhibited the motility of adult female H. contortus in vitro. Subsequently, we inferred three H. contortus proteins (HCON_00134350, HCON_00021470 and HCON_00099760) and five C. elegans proteins (F30A10.9, F15B9.8, B0361.6, DNC-4 and UNC-11) that interacted directly with UMW-9729; however, no conserved protein target was shared between the two nematode species. Future work aims to extend the SAR investigation in these and other parasitic nematode species, and validate individual proteins identified here as possible targets of UMW-9729. Overall, the present study evaluates this anthelmintic candidate and highlights some challenges associated with early anthelmintic investigation.


Assuntos
Anti-Helmínticos , Caenorhabditis elegans , Haemonchus , Animais , Haemonchus/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Anti-Helmínticos/farmacologia , Anti-Helmínticos/química , Relação Estrutura-Atividade , Resistência a Medicamentos
10.
Exp Appl Acarol ; 92(3): 479-506, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38457048

RESUMO

Tick-borne pathogens (TBPs) represent a substantial threat to cattle globally, exerting adverse impacts on production, health, and economic viability. This study delves into the prevalence and implications of TTBPs in cattle sourced from resource-limited smallholder livestock farms situated in southeastern Iran, proximate to Afghanistan and Pakistan. Blood and tick specimens were systematically collected from a cohort of 230 cattle, comprising 150 asymptomatic and 80 symptomatic individuals. Genomic DNA isolated from blood samples underwent rigorous examination for the presence of key TBPs, including Anaplasma marginale, A. phagocytophilum, A. bovis, A. centrale, Babesia bigemina, and Theileria annulata, utilizing multiple genetic markers. Nucleotide sequence analysis facilitated the reconstruction of phylogenetic relationships. The study also evaluated various potential risk factors, such as clinical status, gender, age, breed, tick infestation, and management practices, to elucidate their associations with TTBPs. Among the cattle cohort, a staggering 87.8% (202/230) tested positive for at least one pathogen. Prevalence statistics encompassed A. marginale (72.2%), T. annulata (68.3%), A. phagocytophilum/A. platys-like complex (66.1%), A. centrale (16.7%), B. bigemina (10.0%), and A. bovis (6.1%). Remarkably, mixed infections involving two, three, and four pathogens were detected in 23%, 52.1%, and 2.2% of animals, respectively. Notably, all asymptomatic cattle were positive for at least one TBP. Tick infestation was observed in 62.2% (143/230) of cattle, predominantly caused by Hyalomma anatolicum (82.5%), Rhipicephalus (Boophilus) annulatus (13.1%), and R. sanguineus sensu lato (4.4%). Risk factors linked to TBPs encompassed tick infestation, older age, and crossbred animals. Clinical presentations among symptomatic cattle encompassed fever, anemia, weight loss, anorexia, jaundice, and enlarged superficial lymph nodes. This study underscores the pivotal role of asymptomatic carriers in the propagation of TTBPs within endemic regions. Furthermore, it emphasizes the potential for the implementation of molecular diagnostics to unmask subclinical infections, thereby affording the opportunity for targeted interventions aimed at ameliorating the burden of TTBPs in resource-constrained smallholder dairy farms.


Assuntos
Doenças dos Bovinos , Filogenia , Animais , Bovinos , Irã (Geográfico)/epidemiologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Feminino , Masculino , Fatores de Risco , Doenças Transmitidas por Carrapatos/veterinária , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia , Babesia/isolamento & purificação , Babesia/genética , Prevalência , Anaplasmose/epidemiologia , Anaplasmose/microbiologia , Theileriose/epidemiologia , Theileriose/parasitologia , Babesiose/epidemiologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia
11.
Parasit Vectors ; 17(1): 131, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486232

RESUMO

BACKGROUND: Infection with parasitic nematodes (helminths), particularly those of the order Strongylida (such as Haemonchus contortus), can cause significant and burdensome diseases in humans and animals. Widespread drug (anthelmintic) resistance in livestock parasites, the absence of vaccines against most of these nematodes, and a lack of new and effective chemical entities on the commercial market demands the discovery of new anthelmintics. In the present study, we searched the Global Health Priority Box (Medicines for Malaria Venture) for new candidates for anthelmintic development. METHODS: We employed a whole-organism, motility-based phenotypic screening assay to identify compounds from the Global Health Priority Box with activity against larvae of the model parasite H. contortus, and the free-living comparator nematode Caenorhabditis elegans. Hit compounds were further validated via dose-response assays, with lead candidates then assessed for nematocidal activity against H. contortus adult worms, and additionally, for cytotoxic and mitotoxic effects on human hepatoma (HepG2) cells. RESULTS: The primary screen against H. contortus and C. elegans revealed or reidentified 16 hit compounds; further validation established MMV1794206, otherwise known as 'flufenerim', as a significant inhibitor of H. contortus larval motility (half-maximal inhibitory concentration [IC50] = 18 µM) and development (IC50 = 1.2 µM), H. contortus adult female motility (100% after 12 h of incubation) and C. elegans larval motility (IC50 = 0.22 µM). Further testing on a mammalian cell line (human hepatoma HepG2 cells), however, identified flufenerim to be both cytotoxic (half-maximal cytotoxic concentration [CC50] < 0.7 µM) and mitotoxic (half-maximal mitotoxic concentration [MC50] < 0.7 µM). CONCLUSIONS: The in vitro efficacy of MMV1794206 against the most pathogenic stages of H. contortus, as well as the free-living C. elegans, suggests the potential for development as a broad-spectrum anthelmintic compound; however, the high toxicity towards mammalian cells presents a significant hindrance. Further work should seek to establish the protein-drug interactions of MMV1794206 in a nematode model, to unravel the mechanism of action, in addition to an advanced structure-activity relationship investigation to optimise anthelmintic activity and eliminate mammalian cell toxicity.


Assuntos
Anti-Helmínticos , Anti-Infecciosos , Carcinoma Hepatocelular , Inseticidas , Neoplasias Hepáticas , Adulto , Animais , Humanos , Feminino , Caenorhabditis elegans , Prioridades em Saúde , Anti-Helmínticos/farmacologia , Mamíferos
12.
Physiol Plant ; 176(1): e14183, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38343301

RESUMO

Roots are the main sensing organ, initiating multiple signaling pathways in response to abiotic factors, including nutrients, drought, and salt stress. A focus on improving the root system architecture is a key strategy to mitigate these stresses in wheat crop. In the present study, a diversity panel comprising indigenous landraces and historical cultivars from Pakistan was characterized for the root system architecture (RSA) and important loci were identified using a genome-wide association study (GWAS). RSA of the diversity panel was characterized 30 days after sowing in brunch tubes, and root images were taken. A high-throughput root imaging analysis using Rhizovision software was performed by setting the scale to extract the eight RSA traits and four plant biomass-related traits. GWAS identified 323 association signals for 12 root and biomass traits present on all wheat chromosomes, while the most important and reliable genetic loci (based on pleotropic loci and candidate genes) were identified on chromosomes 2A, 2B, 5A, 5D, 6A, 7B, and 7D for RSA. SNP annotation and transcriptome profiling identified nine candidate genes regulating the RSA and plant biomass traits, including ROOTLESS WITH UNDETECTABLE MERISTEM1, MYB TRANSCRIPTION FACTOR4, BRASSINOSTEROID INSENSITIVE1, SLENDER RICE1, AUXIN-RESPONSIVE FACTOR25, SCARECROW, NARROW LEAF2, PIN-FORMED1 AND PHOSPHATE TRANSCRIPTION FACTOR1. This study provided pre-breeding information for deep-rooting genotypes and associated markers that will accelerate the incorporation of such traits in breeding.


Assuntos
Locos de Características Quantitativas , Triticum , Locos de Características Quantitativas/genética , Triticum/genética , Estudo de Associação Genômica Ampla , Fenótipo , Genótipo , Polimorfismo de Nucleotídeo Único
13.
Int J Occup Saf Ergon ; 30(2): 399-411, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38305082

RESUMO

Objectives. This research investigated the performance properties of protective gloves alongside improvement in thermo-physiological comfort properties. Methods. Knitted gloves prepared from filament stainless steel, filament Kevlar, staple spun Kevlar and filament glass were used in the core, while 100% viscose rayon and 50/50% polyester/viscose rayon were used in the sheath. Gloves were tested for cut resistance, tear resistance, puncture resistance and abrasion resistance as the prime focus, and thermo-physiological comfort properties were also tested. In this research, a multi-response optimization technique, i.e., principal component analysis, was applied to identify the best yarn combination for gloves based on the aforementioned properties. Thermal images were also taken in constant ambient conditions for temperature distribution maps across the hand's surface. Results. All of the results were evaluated statistically with analysis of variance, and concluded that the effects of the core yarn on thermo-physiological properties were less significant. Conclusion. The results revealed that samples having dual-core yarn exhibited better in terms of overall properties. The sample having dual-core filament Kevlar and staple spun Kevlar ranked the best. In addition, developed samples exhibited better comfort properties than the control sample.


Assuntos
Celulose , Luvas Protetoras , Teste de Materiais , Humanos , Estudos Prospectivos , Poliésteres , Aço Inoxidável , Análise de Componente Principal
14.
Vet Parasitol ; 327: 110116, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38244523

RESUMO

This study assessed worm control practices used by Australian Thoroughbred farm managers with an online questionnaire survey. The questionnaire comprised 52 questions (close-ended: 44; open-ended: 8) about farm demography and general husbandry practices, farm managers' knowledge of gastrointestinal nematodes (GIN) and their importance, diagnosis, worm control strategies and anthelmintics, anthelmintic resistance (AR) and grazing management. Following the pilot survey, the link for the questionnaire survey was sent to all (n = 657) registered members of the Thoroughbred Breeders Australia on 12th April 2020. The response rate for the questionnaire was 18.5% (122 of 675). The farm managers reported a good understanding of GIN and their importance in different age groups of horses as most respondents (70% of 122) perceived worm-related illness to be more important in young (i.e., foals, weanlings and yearlings) than adult (> 3 years old) horses. Although most respondents (93%, 113 of 122) used anthelmintics prophylactically to control GIN, only 15% (18 of 122) observed worm-related illness in their horses. Just under 40% of respondents were performing faecal egg counts, with less than 20% using the results of faecal egg counts to guide deworming decisions. The interval-based deworming strategy was the most common method (≥55% of 122 respondents) to control GIN in all age groups of horses. Macrocyclic lactones were the first choice of anthelmintics for all age groups of horses. Although the majority of respondents (88%, 107 of 122) perceived resistance in GIN against commonly used anthelmintics as an important issue in managing worms in horses, only 29% assessed the efficacy of anthelmintics and 91% (111 of 122) were unaware of AR on their properties. Grazing management practices, such as manure removal, were more frequently performed on smaller paddocks (<0.20 ha: 58%) than on larger paddocks (>0.20 ha: 18%). Multiple correspondence analyses showed that the likelihood of suboptimal worm control practices on small farms (n = ≤50 horses) was greater than that of medium (n = 51-100) and large (n = >100) farms. This study provides insights into the demography of Thoroughbred farms in Australia, husbandry practices used by stud managers and their knowledge about worms, control options and AR concerns, thereby paving the way for taking any initiatives to address the problem of AR in GIN of Australian Thoroughbred horses.


Assuntos
Anti-Helmínticos , Doenças dos Cavalos , Nematoides , Animais , Cavalos , Doenças dos Cavalos/prevenção & controle , Doenças dos Cavalos/tratamento farmacológico , Austrália , Criação de Animais Domésticos/métodos , Contagem de Ovos de Parasitas/veterinária , Anti-Helmínticos/uso terapêutico
15.
Int J Parasitol Drugs Drug Resist ; 24: 100522, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38295619

RESUMO

Within the context of our anthelmintic discovery program, we recently identified and evaluated a quinoline derivative, called ABX464 or obefazimod, as a nematocidal candidate; synthesised a series of analogues which were assessed for activity against the free-living nematode Caenorhabditis elegans; and predicted compound-target relationships by thermal proteome profiling (TPP) and in silico docking. Here, we logically extended this work and critically evaluated the anthelmintic activity of ABX464 analogues on Haemonchus contortus (barber's pole worm) - a highly pathogenic nematode of ruminant livestock. First, we tested a series of 44 analogues on H. contortus (larvae and adults) to investigate the nematocidal pharmacophore of ABX464, and identified one compound with greater potency than the parent compound and showed moderate activity against a select number of other parasitic nematodes (including Ancylostoma, Heligmosomoides and Strongyloides species). Using TPP and in silico modelling studies, we predicted protein HCON_00074590 (a predicted aldo-keto reductase) as a target candidate for ABX464 in H. contortus. Future work aims to optimise this compound as a nematocidal candidate and investigate its pharmacokinetic properties. Overall, this study presents a first step toward the development of a new nematocide.


Assuntos
Anti-Helmínticos , Haemonchus , Nematoides , Quinolinas , Animais , Antinematódeos/farmacologia , Anti-Helmínticos/farmacologia , Relação Estrutura-Atividade , Caenorhabditis elegans , Quinolinas/farmacologia
16.
Int J Parasitol Drugs Drug Resist ; 24: 100517, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38064906

RESUMO

This study quantified the extent of anthelmintic resistance (AR) in ascarid and strongylid nematodes against commonly used anthelmintics in Australian Thoroughbred horses. Faecal egg count reduction tests (FECRTs, n = 86) and egg reappearance period (ERP) tests were conducted on 22 farms across Australia. Faecal egg counts (FECs) were determined using the modified McMaster technique, and percent faecal egg count reduction (%FECR) was calculated using the Bayesian hierarchical model and hybrid Frequentist/Bayesian analysis method. The results were interpreted using old (published in 1992) and new (2023) research guidelines of the World Association for the Advancement of Veterinary Parasitology (WAAVP). The species composition of strongylid nematodes was detected utilising a DNA-metabarcoding method using pre- and post-treatment samples. Resistance was observed in strongylid nematodes to commonly used single-active and combination anthelmintics, including ivermectin (IVM %FECR range: 82%-92%; 95% lower credible interval (LCI) range: 80%-90%), abamectin (ABM: 73%-92%; 65%-88%), moxidectin (MOX: 89%-91%; 84%-89%), oxfendazole (OFZ: 0%-56%; 0%-31%) and its combination with pyrantel (OFZ + PYR: 0%-82%; 0%-78%). Resistance in Parascaris spp. was observed to IVM (10%-43%; 0%-36%), ABM (0%; 0%) and MOX (0%; 0%). When the new thresholds recommended by the WAAVP were used, AR was detected in six additional FECRTs for strongylids and three more tests for Parascaris spp., introducing resistance to OFZ and OFZ + PYR in the latter. Shortened ERPs (4-6 weeks) of strongylids were observed in 31 FECRTs in which AR was not detected at 2 weeks post-treatment for all the anthelmintics tested. Among cyathostomins, Cylicocyclus nassatus, Cylicostephanus longibursatus and Coronocyclus coronatus were the most prevalent species at 2 weeks post-treatment, whereas the main species appearing at five weeks following treatments with macrocyclic lactones were Cylicocyclus nassatus, Cylicostephanus longibursatus and Cylicocyclus ashworthi. After treatment with OFZ + PYR, the latter three, plus Coronocyclus coronatus and Cyathostomum catinatum, were detected at 5 weeks post-treatment. Overall, the study highlights the prevalence of AR in both ascarids and strongylid nematodes against commonly used anthelmintic products to control worms in Australian horses. The results indicate that ML combination products provided acceptable efficacy at 2 weeks. However, ERP calculations suggest that products work less effectively than previously measured. It is suggested to regularly monitor the efficacy of the anthelmintics and consider changing the worm control practices to better manage worms and AR in Australian horses.


Assuntos
Anti-Helmínticos , Doenças dos Cavalos , Animais , Anti-Helmínticos/farmacologia , Austrália/epidemiologia , Teorema de Bayes , Resistência a Medicamentos , Fezes/parasitologia , Doenças dos Cavalos/tratamento farmacológico , Doenças dos Cavalos/parasitologia , Cavalos , Contagem de Ovos de Parasitas/veterinária , Strongyloidea/genética
17.
Vet Parasitol ; 325: 110094, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38091893

RESUMO

This study reports the spatial and temporal distribution of ascarid and strongylid nematodes in Thoroughbred horses by age category across different climatic zones in Australia over an 18-month period. Faecal samples (n = 2046) from individual horses were analysed using the modified McMaster technique for faecal egg counts (FECs). Strongylids were identified using PCR-directed next-generation sequencing of the second internal transcribed spacer (ITS-2) of the nuclear ribosomal DNA. Yearlings had the highest prevalence (82%) of strongyle eggs followed by weanlings (79%), foals (58%), wet mares (49%) and dry mares (46%). For Parascaris spp., foals had the highest prevalence (35%) followed by weanlings (21%) and yearlings (10%). The highest mean FECs for Parascaris spp. were observed in foals (525 eggs per gram [EPG] of faeces) while those for strongyles were in yearlings (962 EPG). Among horses that were classified as adults at the time of sampling, 77% (860 of 1119) of mares were low (i.e., <250 EPG) strongyle egg-shedders. Mean strongyle FEC counts were highest in the Mediterranean (818 EPG) followed by summer (599 EPG), winter (442 EPG), and non-seasonal (413 EPG) rainfall zones. Twenty-six nematode species were detected, with Cylicostephanus longibursatus (26.5%), Cylicocyclus nassatus (23.7%) and Coronocyclus coronatus (20.5%) being the most frequently detected species. Their richness and relative abundance varied with horse age, season and climatic zone. In addition, Strongylus equinus and Triodontophorus spp. (T. brevicauda and T. serratus) were also detected. This comprehensive study elucidates spatial (climatic zone) and temporal (i.e., seasonal) trends in prevalence and burdens of intestinal nematodes in Australian horses using non-invasive conventional and molecular methods. The information presented in this study is crucial for developing integrated management strategies to control horse parasites in farmed horses.


Assuntos
Código de Barras de DNA Taxonômico , Óvulo , Cavalos , Animais , Feminino , Código de Barras de DNA Taxonômico/veterinária , Austrália/epidemiologia , Fezes/parasitologia , Strongyloidea/genética , Strongyloides
18.
Bioorg Med Chem ; 98: 117540, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38134663

RESUMO

Global challenges with treatment failures and/or widespread resistance in parasitic worms against commercially available anthelmintics lend impetus to the development of new anthelmintics with novel mechanism(s) of action. The free-living nematode Caenorhabditis elegans is an important model organism used for drug discovery, including the screening and structure-activity investigation of new compounds, and target deconvolution. Previously, we conducted a whole-organism phenotypic screen of the 'Pandemic Response Box' (from Medicines for Malaria Venture, MMV) and identified a hit compound, called ABX464, with activity against C. elegans and a related, parasitic nematode, Haemonchus contortus. Here, we tested a series of 44 synthesized analogues to explore the pharmacophore of activity on C. elegans and revealed five compounds whose potency was similar or greater than that of ABX464, but which were not toxic to human hepatoma (HepG2) cells. Subsequently, we employed thermal proteome profiling (TPP), protein structure prediction and an in silico-docking algorithm to predict ABX464-target candidates. Taken together, the findings from this study contribute significantly to the early-stage drug discovery of a new nematocide based on ABX464. Future work is aimed at validating the ABX464-protein interactions identified here, and at assessing ABX464 and associated analogues against a panel of parasitic nematodes, towards developing a new anthelmintic with a mechanism of action that is distinct from any of the compounds currently-available commercially.


Assuntos
Anti-Helmínticos , Nematoides , Quinolinas , Animais , Humanos , Caenorhabditis elegans , Anti-Helmínticos/farmacologia , Anti-Helmínticos/química , Relação Estrutura-Atividade
19.
PLoS One ; 18(12): e0295820, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38096165

RESUMO

Detection of infections in wildlife species is increasingly important to reduce the risk of spreading zoonotic and economically important parasites, understand disease epidemiology and promote the conservation of wildlife species. Serological tests are key in disease diagnosis and surveillance by detecting immunoglobulins against infectious agents. However, the need for species-specific reagents has limited the application of serological tests in wildlife species. This study evaluated the serum immunoglobulin-binding capability of polyclonal anti-kangaroo antibody and two non-species-specific reagents, including protein A/G and protein L, with the largest range of Australian marsupial species so far, including 32 species representing three major marsupial orders. Immunoglobulin-binding capability was assessed using immunoblotting, enzyme-linked immunosorbent assay and Western blot techniques. Variation in immunoglobulin-binding capability was observed between the three reagents and across the species tested, both across but also within taxonomic groups. Taxonomic distance was thus not always a good predictor of immunoglobulin-binding affinity, emphasizing the need to validate these reagents for each species separately. However, all three reagents bound with the serum immunoglobulins of most marsupial species tested. The findings of this study provide a valuable reference for species differences in affinity to protein A/G, protein L and anti-kangaroo antibody, assisting in the selection of appropriate reagents and the development of sero-immunological assays in Australian marsupials.


Assuntos
Marsupiais , Animais , Animais Selvagens , Austrália , Imunoglobulinas , Ensaio de Imunoadsorção Enzimática/veterinária , Ensaio de Imunoadsorção Enzimática/métodos
20.
Text Res J ; 93(21-22): 5017-5028, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37920184

RESUMO

The release of fragmented fibers (FFs), including microplastics from textiles, during their service life is considered an established source of environmental pollution. The yarn structure is identified to affect the amount and length distribution profile of shed FFs from textiles. In the present work, the impact of yarn structures spun from 100% polyester staple fibers, using commercially relevant spun yarn technologies in the textile industry, on the release of FFs from textiles is studied. The bespoke woven fabric samples produced from three types of spun yarns, which include ring, airjet (air vortex) and rotor yarns, were subjected to an accelerated washing process, for up to five washes, to quantify shed FFs and their length distribution profile. The morphological shapes of FF ends associated with the nature of fiber damage were also investigated. The results demonstrated that airjet and rotor yarn structures had released 28% and 33% less mass of FFs, respectively, as compared to the ring yarn structure during the whole washing process. The length distribution profile identified that the ring yarn structure shed longer length FFs as compared to both airjet and rotor ones. The damaged ends highlight the importance of textile manufacturing processes on the generation of FFs. The results of this study give a better understanding of the yarn structural effect of commercially relevant technologies on shedding of FFs, which are released as a pollutant to the environment.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...