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1.
Vet Parasitol ; 332: 110306, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39265207

RESUMO

Toxoplasma gondii is a globally distributed zoonotic protist, capable of infecting all warm-blooded animals. In Australia, cats (Felis catus) are the only definitive host capable of spreading T. gondii infection via oocysts. Free-roaming cats are widespread in Australia and can play a central role in the ecology of T. gondii. Therefore, understanding the epidemiology of this parasite in stray and feral cats is essential to understanding the potential risk of infection in animals and humans. Due to a lack of easily accessible commercial kits, an in-house modified agglutination test (MAT) was established to test for IgG antibodies against T. gondii, using cell culture-derived T. gondii tachyzoites, and compared with a commercial MAT. A total of 552 serum samples collected during 2018 - 2021 from stray (n = 456) and feral cats (n = 90) (samples with missing data n = 6) from four Australian states, representing different age groups of both sexes, were screened for antibodies against T. gondii. Risk factors for T. gondii infection were assessed using multivariable logistic regression analysis. The in-house MAT had excellent agreement with the commercial MAT and provided a reliable and economical serological tool for T. gondii screening in animals. The overall observed seroprevalence for T. gondii in cats was 40.4 % (223/552). Bodyweight (as a proxy for age), geographical location, season and whether cats were feral or stray, were factors associated with T. gondii seropositivity in cats. Sex was not found to be a risk factor for T. gondii infection in feral and stray cats. This study shows that Australian stray and feral cats have a high T. gondii seroprevalence, which may translate to significant health impacts for wildlife species, livestock and the public.

2.
Commun Eng ; 3(1): 124, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251826

RESUMO

Linear polarization (LP) and circular polarization (CP) holds paramount importance in Ku, K, and Ka bands for satellite based communication, and remote sensing applications. Satellite based remote sensing applications face challenges like atmospheric attenuation, noise & interference, and signal degradation. Moreover, satellite based communication application demands CP in two distinct, non-adjacent frequency bands with orthogonal polarizations at greater oblique angles, considering the unpredictable incidence angles of electromagnetic (EM) waves. Addressing these challenges, an innovative metasurface polarization converter is proposed to operate efficiently across the Ku-band (13.5-18.0 GHz), K-band (18.0-26.5 GHz), and Ka-band (26.5-38.5 GHz) frequency ranges. The converter achieves left-handed circular polarization (LHCP) in the Ku- and Ka-bands within the frequency ranges of 14.57-15.65 GHz and 27.47-33.85 GHz for y-polarized incident EM waves. Additionally, it provides right-handed circular polarization (RHCP) in the K- and Ka-bands at 17.27-23.92 GHz and 35.87-38.32 GHz for y-polarized incident EM waves. The LP conversion ratio exceeds 95% in the frequency bands of 15.97-16.85 GHz, 24.70-26.65 GHz, and 34.37-35.45 GHz for y-polarized, LHCP, and RHCP incident EM waves, respectively. The metasurface exhibits robust performance up to incidence angles of 45 degrees under oblique conditions. Experimental validation using traditional board-circuit manufacturing demonstrates close agreement between measured co- and cross-polarized reflection coefficients and simulations in the 13.5-18 GHz, and 24-38.5 GHz frequency range. Thin metasurface with a thickness of only 0.64 = 0.013λo mm, the proposed design outperforms existing studies in the literature, establishing its competitive edge in terms of structure and performance.

3.
RSC Adv ; 14(38): 28058-28076, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39228757

RESUMO

The multifaceted challenges in treating full-thickness acid burn wounds including impaired tissue regeneration, increased risk of infection, and the pursuit of functional and aesthetically pleasing outcomes, highlights the need for innovative therapeutic approaches for their treatment. The exceptional biochemical and mechanical properties of hydrogels, particularly their extracellular matrix-like nature and their potential to incorporate functional ingredients positions them as promising materials for wound dressings, offering a potential solution to the complexities of full-thickness burn wound management. The current study has integrated functional ingredients (starch and α-terpineol), known for their angiogenic, fibroblast-adhesive, and anti-inflammatory properties into an α-terpineol loaded, electron beam crosslinked polyvinyl alcohol/tapioca pearl starch hydrogel. The hydrogel was then explored for its efficacy in treating full-thickness acid burns. The hydrogel sheets, fabricated using a 25 kGy electron beam, were characterized for structural and functional properties. Surface morphology, gel fraction, swelling ratio, moisture retention capacity and thermal stability were also evaluated. PVA/tapioca starch hydrogel demonstrated optimal macroporosity, mechanical strength, thermal stability, water retention, and moisturizing ability, making it ideal for the intended application. In vitro skin compatibility analysis of α-terpineol-loaded hydrogel confirmed its biocompatibility, demonstrating 90% fibroblast viability. In vivo sensitivity testing on normal rat skin showed no inflammatory response. Analysis of the full-thickness rat chemical burn wounds treated with the hydrogels demonstrated that α-terpineol (AT) loaded e-beam crosslinked PVA/tapioca starch hydrogels increased the rate of wound closure, promoted re-epithelialization, facilitated collagen deposition, stimulated angiogenesis, and promoted keratin deposition, ultimately leading to healing of both thick dermal and epidermal tissues, as well as partial restoration of skin appendages over a duration of 30 days as confirmed by the histological and immunohistochemistry staining. Collectively, this study indicates that α-terpineol (AT) loaded e-beam crosslinked PVA/tapioca starch hydrogel holds promise as a cost-effective and efficient wound dressing for expediting full thickness acid burn wound healing, thus expanding the practical applications of the natural polymer based sheet hydrogel dressings.

4.
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
5.
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.

6.
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.

7.
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
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.
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
10.
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
11.
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
12.
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
13.
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
14.
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
15.
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
16.
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
17.
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
18.
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
19.
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
20.
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
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