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1.
Environ Sci Pollut Res Int ; 30(56): 118280-118290, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37737946

RESUMEN

Terminal heat during reproductive stages of wheat (Triticum aestivum L.) limits the productivity of the crop. Magnesium (Mg) is an essential macronutrient that is involved in many physiological and biochemical processes to affect photosynthesis and seed weight. The present study comparatively evaluated Mg applied to soil (80 kg MgSO4·7H2O ha-1) and to plant foliage (4% w/v) in improving wheat performance under terminal heat. Wheat crop was grown in two sets of treatments until the booting stage, and then one set of plants was shifted to a glasshouse (±5 °C) at the booting stage to grow until maturity in comparison to control plants kept under ambient warehouse condition. Heat stress reduced the pollen viability while foliar- and soil-applied Mg improved it by 3% and 6% under heat stress, respectively, compared to the control without Mg treatment. The 100-seed weight, spike length, and biological yield reduced by 39%, 19%, and 50% under heat stress; however, foliar and soil application increased 100-seed weight by 45% and 40%, spike length by 8% and 5%, and biological yield by 35% and 25% under heat stress, respectively. Soil Mg showed maximum SPAD chlorophyll values; however, response was statistically similar to that of foliar Mg as compared to the control without Mg supply. Membrane stability decreased (4%) due to heat stress while foliar and soil treatments improved membrane stability by 8% and 5% compared to that of the control, respectively. Thus, Mg application through soil or plant foliage can be an effective way to reduce negative impacts of terminal heat in wheat by improving pollen viability at anthesis and 100-seed weight that was attributed to increased chlorophyll contents during anthesis.


Asunto(s)
Magnesio , Triticum , Magnesio/farmacología , Temperatura , Semillas , Clorofila/farmacología , Suelo/química , Polen , Fertilización
2.
Cureus ; 15(12): e51038, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38269231

RESUMEN

This narrative review explores the complex relationship between cancer medicines and cardiovascular health in the junction of oncology and cardiology, known as cardio-oncology. The study examines the historical development of cancer treatments and highlights the growing importance of cardiovascular problems in patient care. This text delves into the topic of cardiotoxicity, examining both conventional chemotherapeutic drugs like anthracyclines and more recent tyrosine kinase and immune checkpoint inhibitors. The complex molecular and cellular mechanisms that control cardiovascular problems are explained, including an understanding of how genetic predisposition influences an individual's sensitivity. The narrative expands into the crucial realm of risk stratification and evaluation, revealing advanced instruments for identifying cardiovascular risk in cancer patients. The importance of non-invasive imaging methods and biomarkers in early detection and continuous monitoring is emphasized. The prioritization of preventive tactics emphasizes the need to take proactive measures incorporating therapies to protect the heart throughout cancer treatment. It also highlights the significance of making lifestyle improvements to reduce risk factors. The narrative emphasizes the changing collaborative treatment environment, advocating for merging oncologists and cardiologists in a coordinated endeavor to maximize patient outcomes. In addition to clinical factors, the review explores the critical domain of patient education and support, acknowledging its crucial role in promoting informed decision-making and improving overall patient well-being. The latter portions of the text anticipate and consider upcoming treatments and existing research efforts that offer the potential for the future of cardio-oncology. This review seeks to provide a detailed viewpoint on the intricate connection between cancer treatments and cardiovascular well-being. Its objective is to encourage a more profound comprehension of the subject and prompt careful contemplation regarding the comprehensive care of cancer patients who confront the intricate difficulties presented by their treatment plans.

3.
Pak J Pharm Sci ; 35(4(Special)): 1281-1286, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36218108

RESUMEN

Hertia intermedia is a traditional medicinal plant of Balochistan, used for pain management and stomach problems. Current research work was intended to evaluate the anti-inflammatory and analgesic activities of crude ethanolic extract of H. intermedia. Anti-inflammatory activity was determined by the carrageenan-induced and histamine-induce Rat paw edema in rats, analgesic activity was determined by acetic acid-Induced writhing test, formalin-induced hind paw licking in mice and Tail immersion test. H. intermedia crude ethanolic extract showed significant (p<0.05) effect in both carrageenan and histamine-induced rat paw edema at both 250 and 500 mg/kg oral doses. There were significant analgesic activities in comparison with standard drug and control (p<0.05). It is concluded that H. intermedia crude ethanolic extract possesses significant anti-inflammatory and analgesic effects. However further studies may be carried out to isolate the phytochemicals responsible for anti-inflammatory and analgesic activities.


Asunto(s)
Asteraceae , Histamina , Acetatos , Ácido Acético , Analgésicos/uso terapéutico , Animales , Antiinflamatorios/uso terapéutico , Carragenina , Edema/inducido químicamente , Edema/tratamiento farmacológico , Etanol/uso terapéutico , Histamina/efectos adversos , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Ratones , Dolor/inducido químicamente , Dolor/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Ratas
4.
Isotopes Environ Health Stud ; 58(2): 214-227, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35135400

RESUMEN

This article presents the results of a study conducted to measure the gross alpha, gross beta activities in medicinal plant samples collected from different districts of Azad Kashmir, Pakistan. The ASC-950-DP gasless high-speed counter was used for the measurement of gross α/ß activities. Measured activities have been used to assess age-dependent annual effective doses for infants, one-, five-, ten-, and fifteen-year-old and adult people. For a medicinal plant consumption rate (MPCR) of 1.8 kg a-1, the average gross alpha and beta annual committed effective dose (ACED) delivered to one-, five-, ten-, fifteen-year-olds and adults fall below the WHO recommended level (290 µSv a-1) and that reported in the UNSCEAR 2000 (0.3 mSv a-1) report. Results obtained for the current study show that the radiological hazard related to the consumption of natural radionuclides in medicinal plants is inconsequential with exception of the ACED delivered to infants at an MPCR of 1.8 g a-1 and higher values.


Asunto(s)
Plantas Medicinales , Monitoreo de Radiación , Contaminantes Radiactivos del Agua , Adulto , Ingestión de Alimentos , Humanos , Lactante , Dosis de Radiación , Monitoreo de Radiación/métodos , Radioisótopos/análisis , Contaminantes Radiactivos del Agua/análisis
5.
Trop Anim Health Prod ; 54(2): 107, 2022 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-35187616

RESUMEN

BACKGROUND: Haemonchosis is a fatal disease of small ruminants caused by the parasite Haemonchus contortus (H. contortus). The most common drugs used in the treatment of H. contortus include albendazole, oxfendazole, and ivermectin. However, as previously reported in the treatment of haemonchosis, these medicines have acquired drug resistance problems over time. Interestingly, natural plant compounds have demonstrated promising effects in the treatment of H. contortus. Therefore, the current study evaluated the effects of plant extract, Ferula asafetida, against common drugs such as albendazole, oxfendazole, ivermectin, and closantel for the treatment of haemonchosis in small ruminants. METHODOLOGY: The current study was conducted on different small ruminant farms in Kasur District, Punjab, Pakistan. The positive animals (n = 720) after coprological examination were selected in this study and divided into two major groups (n = 360 goats and n = 360 sheep). Further, animals were divided into five treatment groups (A-E) and one control group with no treatment (F). Albendazole, oxfendazole, ivermectin, closantel, and Ferula asafetida were administered orally to groups A-E, respectively. The eggs per gram feces (EPG) were determined through the McMaster technique on days 0, 7th, and 14th of treatment. RESULTS: The results showed a significantly higher efficacy of closantel and Ferula asafetida against H. contortus in both goats (100% and 70%; p < 0.05) and sheep (99% and 87%; p < 0.05), respectively. No correlation was observed between EPG reduction with age and gender in both goats and sheep. CONCLUSION: Allopathic drug closantel and herbal drug, Ferula asafetida, have been proved an effective dewormer against H. contortus in small ruminants.


Asunto(s)
Antihelmínticos , Ferula , Enfermedades de las Cabras , Hemoncosis , Haemonchus , Enfermedades de las Ovejas , Albendazol/farmacología , Albendazol/uso terapéutico , Animales , Antihelmínticos/uso terapéutico , Bencimidazoles , Resistencia a Medicamentos , Enfermedades de las Cabras/tratamiento farmacológico , Cabras , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Hemoncosis/veterinaria , Ivermectina/farmacología , Ivermectina/uso terapéutico , Óvulo , Recuento de Huevos de Parásitos/veterinaria , Salicilanilidas , Ovinos , Enfermedades de las Ovejas/tratamiento farmacológico , Enfermedades de las Ovejas/parasitología
6.
Pak J Pharm Sci ; 35(6(Special)): 1739-1746, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36861237

RESUMEN

Grewia asiatica L. is a potential medicinal plant used for various diseases in traditional medicine. Current study was aimed to evaluate the cardio protective, anti-inflammatory, analgesic and CNS depressant activities of Grewia asiatica L. fruit extract. In cardio protective activity myocardial injury was produced by injection of Isoproterenol (200 mg/kg, s.c), G. asiatica 250 and 500mg/kg treated groups significantly (p<0.05) decreased the level of serum AST, ALT, LDH and CKMB, hence produced cardio protective effect. In analgesic activities G. asiatica produced significant (p<0.05) analgesic effects in acetic acid induced writhing, formalin, paw pressure and tail immersion test. G. asiatica at 250 and 500mg/kg oral dose, significantly (p<0.05) reduced the rat paw edema in carrageen an induced rat paw edema test. G. asiatica extract also produced significant CNS depressant effects in open field, hole board and thiopental sodium induced sleeping time. Findings of the current study suggest that G. asiatica fruit extract showed potential pharmacological effects and can be utilized in alternative medicine.


Asunto(s)
Depresores del Sistema Nervioso Central , Grewia , Animales , Ratas , Frutas , Antiinflamatorios no Esteroideos , Extractos Vegetales/farmacología
7.
Molecules ; 26(14)2021 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-34299431

RESUMEN

In the present study, we established a practical and cost-effective high throughput screening assay, which relies on the measurement of the motility of Caenorhabditis elegans by infrared light-interference. Using this assay, we screened 14,400 small molecules from the "HitFinder" library (Maybridge), achieving a hit rate of 0.3%. We identified small molecules that reproducibly inhibited the motility of C. elegans (young adults) and assessed dose relationships for a subset of compounds. Future work will critically evaluate the potential of some of these hits as candidates for subsequent optimisation or repurposing as nematocides or nematostats. This high throughput screening assay has the advantage over many previous assays in that it is cost- and time-effective to carry out and achieves a markedly higher throughput (~10,000 compounds per week); therefore, it is suited to the screening of libraries of tens to hundreds of thousands of compounds for subsequent evaluation and development. The present phenotypic whole-worm assay should be readily adaptable to a range of socioeconomically important parasitic nematodes of humans and animals, depending on their dimensions and motility characteristics in vitro, for the discovery of new anthelmintic candidates. This focus is particularly important, given the widespread problems associated with drug resistance in many parasitic worms of livestock animals globally.


Asunto(s)
Antihelmínticos/análisis , Evaluación Preclínica de Medicamentos/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Animales , Antihelmínticos/aislamiento & purificación , Antihelmínticos/farmacología , Antiinfecciosos/farmacología , Antinematodos/análisis , Antinematodos/farmacología , Caenorhabditis elegans/efectos de los fármacos , Resistencia a Medicamentos/efectos de los fármacos , Larva/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología
8.
Biomed Res Int ; 2021: 5578914, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33884265

RESUMEN

The most common ethnomedicinal plants being effective in respiratory disorders were studied for the first time in Bahawalpur District. The herbal medication represents a low-cost treatment for the local community. There is a need for documenting the traditional uses of plants for further investigation of bioactive compounds. Using a qualitative approach, the ethnobotanical data was collected from the district of Bahawalpur, Pakistan, from February 2018 to February 2020 through semistructured interviews with the local people and traditional healers. The quantitative analysis included use value, informant consensus factor, family importance value, and relative frequency citation. A total of 20 indigenous plants belonging to 17 families were documented from 185 informants. These plants were claimed to be used for the treatment of 10 respiratory ailments. The plant habit, part of the plant used, and mode of preparation were standardized for authentication. The herbs are the most used life form (55%), while trees and shrubs are also used. Leaves dominate with high use value (47.62%) followed by fruit, stem, flower, and other parts of plants. For the preparation of traditional remedies, decoction (76.19%) and extract (71.43%) are common preparation methods. However, other methods of paste infusion, powder juice, and ash are used to a lower extent. The plants with higher use value are Glycyrrhiza glabra, Acacia arabica, and Mentha piperita; these have significant potential therapeutic activity for respiratory disease. The ethnomedicinal importance of plants against respiratory diseases used by the local population (traditional healers) is the commercial availability of the herbal product. It is a first-time study in this area to fill the gap between traditional practices and synthetic medicine to screen out the phytochemical and pharmacological properties of plants that have a highly futuristic use value to develop antibiotic drug with least side effects by using sustainable methods.


Asunto(s)
Fitoterapia , Plantas Medicinales/química , Trastornos Respiratorios/terapia , Adulto , Anciano , Etnobotánica , Femenino , Geografía , Humanos , Masculino , Persona de Mediana Edad , Pakistán
9.
J Med Chem ; 64(1): 840-844, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33352050

RESUMEN

A series of 1-methyl-1H-pyrazole-5-carboxamides were synthesized as potent inhibitors of the parasitic nematode of sheep, Haemonchus contortus. These compounds did not show overt cytotoxicity to a range of mammalian cell lines under standard in vitro culture conditions, had high selectivity indices, and were progressed to an acute toxicity study in a rodent model. Strikingly, acute toxicity was observed in mice. Experiments measuring cellular respiration showed a dose-dependent inhibition of mitochondrial respiration. Under these conditions, potent cytotoxicity was observed for these compounds in rat hepatocytes suggesting that the potent acute mammalian toxicity of this chemotype is most likely associated with respiratory inhibition. In contrast, parasite toxicity was not correlated to acute toxicity or cytotoxicity in respiring cells. This paper highlights the importance of identifying an appropriate in vitro predictor of in vivo toxicity early on in the drug discovery pipeline, in particular assessment for in vitro mitochondrial toxicity.


Asunto(s)
Antiprotozoarios/farmacología , Haemonchus/efectos de los fármacos , Pirazoles/química , Animales , Antiprotozoarios/química , Supervivencia Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Femenino , Masculino , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Pirazoles/farmacología , Ratas , Ovinos/parasitología , Relación Estructura-Actividad
10.
Trop Anim Health Prod ; 53(1): 23, 2020 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-33219403

RESUMEN

This study was conducted to study the effect of protease as well as three dietary crude protein levels on growth and nutrient digestibility in broilers. The broiler chickens (n = 540) were assigned to six dietary treatments with six replicates. Three dietary crude protein (CP) levels (17, 19, and 21%) along with two levels of protease (0 and 30,000 IU/kg) were investigated in 3 × 2 factorial arrangement during the starter phase. Body weight was higher (P < 0.05) in group fed with CP-21; however, feed intake was significantly (P < 0.05) lower in CP-19 and CP-21. Resultantly, FCR was significantly (P < 0.05) improved in birds fed with CP-21. Similarly, body weight, feed intake, and FCR were significantly (P < 0.05) improved in enzyme-treated birds compared to the untreated birds. For practical purpose, birds fed CP-19 with protease enzyme resulted in improved FCR compared to birds fed with CP-21. The results revealed that CP and apparent metabolizable energy (AME) were significantly (P < 0.05) higher in birds fed with CP-21 along with supplementation of enzyme while abdominal fat was significantly (P < 0.05) lower in the same group compared to birds fed with CP-17. These results indicated that a diet having 21% CP supplemented with 30,000 IU/kg protease enzyme was superior in improving the performance and digestibility of nutrients in broiler during the starter phase.


Asunto(s)
Pollos/fisiología , Proteínas en la Dieta/metabolismo , Digestión/efectos de los fármacos , Nutrientes/fisiología , Péptido Hidrolasas/metabolismo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Péptido Hidrolasas/administración & dosificación , Distribución Aleatoria
11.
Molecules ; 25(8)2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-32344703

RESUMEN

Kava extract, an aqueous rhizome emulsion of the plant Piper methysticum, has been used for centuries by Pacific Islanders as a ceremonial beverage, and has been sold as an anxiolytic agent for some decades. Kavalactones are a major constituent of kava extract. In a previous investigation, we had identified three kavalactones that inhibit larval development of Haemonchus contortus in an in vitro-bioassay. In the present study, we synthesized two kavalactones, desmethoxyyangonin and yangonin, as well as 17 analogues thereof, and evaluated their anthelmintic activities using the same bioassay as employed previously. Structure activity relationship (SAR) studies showed that a 4-substituent on the pendant aryl ring was required for activity. In particular, compounds with 4-trifluoromethoxy, 4-difluoromethoxy, 4-phenoxy, and 4-N-morpholine substitutions had anthelmintic activities (IC50 values in the range of 1.9 to 8.9 µM) that were greater than either of the parent natural products-desmethoxyyangonin (IC50 of 37.1 µM) and yangonin (IC50 of 15.0 µM). The synthesized analogues did not exhibit toxicity on HepG2 human hepatoma cells in vitro at concentrations of up to 40 µM. These findings confirm the previously-identified kavalactone scaffold as a promising chemotype for new anthelmintics and provide a basis for a detailed SAR investigation focused on developing a novel anthelmintic agent.


Asunto(s)
Antihelmínticos/síntesis química , Antihelmínticos/farmacología , Haemonchus/efectos de los fármacos , Kava/química , Animales , Relación Dosis-Respuesta a Droga , Larva/efectos de los fármacos , Estructura Molecular , Pruebas de Sensibilidad Parasitaria
12.
Vet World ; 13(12): 2596-2607, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33487976

RESUMEN

BACKGROUND AND AIM: Mastitis has been identified as the most prevalent and economically imperative disease among dairy animals. Thus, understanding its common bacterial pathogens and risk factors is necessary to improve udder health at herd, region, or country level. However, scientific research on caprine mastitis, especially on Beetal breed, has remained to be insufficient in Pakistan. Therefore, this study aimed to evaluate the epidemiology and antibiogram assay of common mastitis-causing bacterial agents, that is, Staphylococcus, Streptococcus, and Escherichia coli, in dairy goats. MATERIALS AND METHODS: In total, 500 Beetal goats, irrespective of age and those that were not treated with any kind of antimicrobial agents during the past 120 h, were screened using California Mastitis Test in Pattoki, Kasur District, whereas epidemiological factors were recorded. The milk samples of mastitic goats were then collected and processed using standard methods. Each sample was primarily cultured on nutrient agar. Using a specific medium, each bacterial colony was separated using several streak methods. Six antibiotic disks belonging to different antibiotic groups were used for antibiogram profiling of bacterial isolates. Chi-square test was used to assess the association of baseline characteristics and mastitis occurrence. Meanwhile, multivariable logistic regression (p<0.001) was utilized to determine the risk factors associated with positive and negative dichotomous outcome of mastitis. RESULTS: The results revealed that the overall prevalence of goat mastitis was 309 (61.8%), in which 260 (52%) and 49 (9.8%) cases were positive for subclinical mastitis (SCM) and clinical mastitis (CM), respectively. Streptococcus and E. coli were found to be the predominant isolates causing SCM and CM, respectively (p<0.001). It was observed that amoxicillin+clavulanic acid was highly sensitive to isolates of Staphylococcus and Streptococcus and ceftiofur sodium to isolates of Streptococcus and E. coli., while enrofloxacin was found to be sensitive to isolates of Streptococcus and E. coli. Risk factors such as herd structure, deworming, vaccination, presence of ticks, use of teat dip and mineral supplements, feeding type, age, parity, housing, blood in the milk, milk leakage, milk taste, and milk yield were found to have the strongest association with mastitis occurrence, while ease of milking has moderate association. CONCLUSION: In the area examined, cases of SCM were found to be higher compared with that of CM, and ceftiofur sodium has been identified as the preferred treatment in both clinical and subclinical forms of caprine mastitis in Beetal goats. Risk factors for mastitis that was identified in this study can form the basis for the creation of an udder health control program specific for dairy goats. We hope our findings could raise awareness of the risk factors and treatment approaches for common mastitis-causing bacterial agents.

13.
Chin Med Sci J ; 35(4): 315-322, 2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33413747

RESUMEN

Objectives Blood stream infections (BSIs) are the main cause of morbidity and mortality in children worldwide. The present study was carried out to determine the prevalence of BSI with a focus on the identification of the causative agent of BSI, and to further evaluate the antibiotic susceptibility profile of the causing bacterial pathogens.Methods A cross-section study was carried out at the tertiary care hospital in Peshawar, Pakistan from January to December, 2018. Blood samples were collected in BACTECTM bottles and standard microbiological protocols were applied for the isolation and identification of bacterial strains. The antibiotic susceptibility tests were performed using disc diffusion method as per the 2014 guideline of Clinical Laboratory Standard Institute (CLSI).Results Of 567 blood cultures in total, 111(19.6%) were positive for BSI. Male children were 64 % (71/111) and female children were 36% (40/111). For the causative predominant group of microorganisms, Gram-negative bacteria were identified in 79 (71.1%) isolates, and Gram-positive bacteria in 32 (28.9%) isolates. The common bacteria of isolates were S. typhi (n=35, 31.5%), E. coli (n=19, 17.1%), S. aureus (n=18, 16.2%), K. pneumonia (n=12, 10.8%), and Enterococcus species (n=7, 6.3%). The 36.7% (29/79) isolates of Gram-negative bacteria were ESBL producers, and 61.1% (11/18) of S. aureus isolates were methicillin resistant. Overall, 72.9% isolates were multidrug resistant.Conclusions Gram-negative bacteria were the main cause of pediatric BSIs, where the predominant microorganism was S. typhi. Remarkably, majority of the S. typhi isolates were resistant to ciprofloxacin.


Asunto(s)
Antibacterianos/uso terapéutico , Sepsis/tratamiento farmacológico , Sepsis/microbiología , Antibacterianos/farmacología , Niño , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Pakistán , Centros de Atención Terciaria
14.
Sci Rep ; 9(1): 14996, 2019 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-31628383

RESUMEN

Tuberculosis (TB), caused by Mycobacterium tuberculosis bacteria, is a leading infectious cause of mortality worldwide, including in Pakistan. Drug resistant M. tuberculosis is an emerging threat for TB control, making it important to detect the underlying genetic mutations, and thereby inform treatment decision making and prevent transmission. Whole genome sequencing has emerged as the new diagnostic to reliably predict drug resistance within a clinically relevant time frame, and its deployment will have the greatest impact on TB control in highly endemic regions. To evaluate the mutations leading to drug resistance and to assess for evidence of the transmission of resistant strains, 81 M. tuberculosis samples from Khyber Pakhtunkhwa province (North West Pakistan) were subjected to whole genome sequencing and standard drug susceptibility testing for eleven anti-TB drugs. We found the majority of M. tuberculosis isolates were the CAS/Delhi strain-type (lineage 3; n = 57; 70.4%) and multi-drug resistant (MDR; n = 62; 76.5%). The most frequent resistance mutations were observed in the katG and rpoB genes, conferring resistance to isoniazid and rifampicin respectively. Mutations were also observed in genes conferring resistance to other first and second-line drugs, including in pncA (pyrazinamide), embB (ethambutol), gyrA (fluoroquinolones), rrs (aminoglycosides), rpsL, rrs and giB (streptomycin) loci. Whilst the majority of mutations have been reported in global datasets, we describe unreported putative resistance markers in katG, ethA (ethionamide), gyrA and gyrB (fluoroquinolones), and pncA. Analysis of the mutations revealed that acquisition of rifampicin resistance often preceded isoniazid in our isolates. We also observed a high proportion (17.6%) of pre-MDR isolates with fluoroquinolone resistance markers, potentially due to unregulated anti-TB drug use. Our isolates were compared to previously sequenced strains from Pakistan in a combined phylogenetic tree analysis. The presence of lineage 2 was only observed in our isolates. Using a cut-off of less than ten genome-wide mutation differences between isolates, a transmission analysis revealed 18 M. tuberculosis isolates clustering within eight networks, thereby providing evidence of drug-resistant TB transmission in the Khyber Pakhtunkhwa province. Overall, we have demonstrated that drug-resistant TB isolates are circulating and transmitted in North West Pakistan. Further, we have shown the usefulness of whole genome sequencing as a diagnostic tool for characterizing M. tuberculosis isolates, which will assist future epidemiological studies and disease control activities in Pakistan.


Asunto(s)
Antituberculosos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple/genética , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Secuenciación Completa del Genoma/métodos , Adolescente , Adulto , Secuencia de Bases , ADN Bacteriano/genética , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Mutación , Mycobacterium tuberculosis/aislamiento & purificación , Pakistán/epidemiología , Filogenia , Polimorfismo de Nucleótido Simple , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/transmisión , Adulto Joven
15.
Parasit Vectors ; 12(1): 191, 2019 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-31039802

RESUMEN

BACKGROUND: Due to anthelmintic resistance problems, there is a need to discover and develop new drugs for the treatment and control of economically important and pathogenic nematodes of livestock animals. With this focus in mind, we screened 236 compounds from a library (called the 'Kurz-box') representing chemically diverse classes such as heterocyclic compounds (e.g. thiazoles, pyrroles, quinolines, pyrimidines, benzo[1,4]diazepines), hydoxamic acid-based metalloenzyme inhibitors, peptidomimetics (bis- and tris-pyrimidoneamides, alkoxyamides) and various intermediates on Haemonchus contortus, one of the most important parasitic nematodes of ruminants. METHODS: In the present study, we tested these compounds, and measured the inhibition of larval motility and development of exsheathed third-stage (xL3) and fourth-stage (L4) larvae of H. contortus using an optimised, whole-organism phenotypic screening assay. RESULTS: Of the 236 compounds, we identified two active compounds (called BLK127 and HBK4) that induced marked phenotypic changes in the worm in vitro. Compound BLK127 induced an 'eviscerated' phenotype in the xL3 stage and also inhibited L4 development. Compound HBK4 exerted a 'curved' phenotype in both xL3s and L4s. CONCLUSIONS: The findings from this study provide a basis for future work on the chemical optimisation of these compounds, on assessing the activity of optimised compounds on adult stages of H. contortus both in vitro and in vivo (in the host animal) and against other parasitic worms of veterinary and medical importance.


Asunto(s)
Antihelmínticos/farmacología , Haemonchus/crecimiento & desarrollo , Animales , Antihelmínticos/química , Evaluación Preclínica de Medicamentos , Femenino , Haemonchus/efectos de los fármacos , Concentración 50 Inhibidora , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Masculino , Fenotipo
16.
Artículo en Inglés | MEDLINE | ID: mdl-30739078

RESUMEN

Due to the widespread occurrence and spread of anthelmintic resistance, there is a need to develop new drugs against resistant parasitic nematodes of livestock animals. The Nobel Prize-winning discovery and development of the anti-parasitic drugs avermectin and artemisinin has renewed the interest in exploring natural products as anthelmintics. In the present study, we screened 7500 plant extracts for in vitro-activity against the barber's pole worm, Haemonchus contortus, a highly significant pathogen of ruminants. The anthelmintic extracts from two plants, Cryptocarya novoguineensis and Piper methysticum, were fractionated by high-performance liquid chromatography (HPLC). Subsequently, compounds were purified from fractions with significant biological activity. Four α-pyrones, namely goniothalamin (GNT), dihydrokavain (DHK), desmethoxyyangonin (DMY) and yangonin (YGN), were purified from fractions from the two plants, GNT from C. novoguineensis, and DHK, DMY and YGN (= kavalactones) from P. methysticum. The three kavalactones induced a lethal, eviscerated (Evi) phenotype in treated exsheathed third-stage larvae (xL3s), and DMY and YGN had moderate potencies (IC50 values of 31.7 ±â€¯0.23 µM and 23.7 ±â€¯2.05 µM, respectively) at inhibiting the development of xL3s to fourth-stage larvae (L4s). Although GNT had limited potency (IC50 of 200-300 µM) at inhibiting L4 development, it was the only compound that reduced L4 motility (IC50 of 6.25-12.50 µM). The compounds purified from each plant affected H. contortus in an irreversible manner. These findings suggest that structure-activity relationship studies of α-pyrones should be pursued to assess their potential as anthelmintics.


Asunto(s)
Antihelmínticos/farmacología , Cryptocarya/química , Haemonchus/efectos de los fármacos , Piperaceae/química , Extractos Vegetales/farmacología , Pironas/farmacología , Animales , Cromatografía Líquida de Alta Presión , Ensayos Analíticos de Alto Rendimiento , Concentración 50 Inhibidora , Larva/efectos de los fármacos , Pruebas de Sensibilidad Parasitaria , Fitoquímicos/farmacología
17.
Vet Parasitol ; 265: 91-100, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30638526

RESUMEN

This study aimed to assess current worm control practices used by Australian alpaca farmers with an online questionnaire survey. The questionnaire contained questions about farm demography and general husbandry practices, farmers' knowledge about gastrointestinal nematodes (GINs) and their importance, the use of worm control strategies and anthelmintics, and grazing management. A link for the questionnaire survey was sent to all (n = 954) registered members of the Australian Alpaca Association in July 2015. The response rate for the questionnaire was 25% (239/954). The majority of respondents were from small (≤ 50 alpacas; 64%, 153/239) followed by medium (50-100 alpacas; 24%, 57/239) and large (>100 alpacas; 12%, 29/239) farms. Findings revealed that the majority of respondents kept Huacaya alpacas to produce high-quality fibre and alpacas were usually kept with other domestic ruminants (e.g. cattle and sheep). Although half of alpaca farmers (114/220) perceived that GINs were an important health problem of alpacas, with Haemonchus spp. being the most common nematode, the majority of them (174/220) used anthelmintics for nematode control. Macrocyclic lactones, a commercial combination of four anthelmintics (abamectin, albendazole, closantel and levamisole) and monepantel were the three most commonly used dewormers by Australian alpaca farmers. Although a significant proportion (166/213) of respondents used a quarantine drench for alpacas, very few respondents were aware of strategic deworming and the issue of anthelmintic resistance. Alpaca farmers mostly used anthelmintics at the dose rate recommended for sheep (47%, 79/167) and cattle (9%, 15/167), though some used 1.5 (31%, 51/167) and 2 (13%, 22/167) times the dose rate recommended for sheep. The majority of small herds used anthelmintics at the dose rate recommended for sheep and cattle while medium and large herds used anthelmintics at 1.5 to 2 times the dose rate recommended for sheep. This study provides invaluable insights into the demography of alpaca farms in Australia, husbandry practices used by alpaca farmers and their knowledge about worms and their control, thereby paving the way for developing guidelines for the control of GINs of alpacas.


Asunto(s)
Crianza de Animales Domésticos , Antihelmínticos/uso terapéutico , Camélidos del Nuevo Mundo , Helmintiasis Animal/prevención & control , Animales , Australia , Recolección de Datos , Agricultores , Helmintiasis Animal/tratamiento farmacológico , Encuestas y Cuestionarios
18.
J Med Chem ; 61(23): 10875-10894, 2018 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-30403349

RESUMEN

A phenotypic screen of a diverse library of small molecules for inhibition of the development of larvae of the parasitic nematode Haemonchus contortus led to the identification of a 1-methyl-1 H-pyrazole-5-carboxamide derivative with an IC50 of 0.29 µM. Medicinal chemistry optimization targeted modifications on the left-hand side (LHS), middle section, and right-hand side (RHS) of the scaffold in order to elucidate the structure-activity relationship (SAR). Strong SAR allowed for the iterative and directed assembly of a focus set of 64 analogues, from which compound 60 was identified as the most potent compound, inhibiting the development of the fourth larval (L4) stage with an IC50 of 0.01 µM. In contrast, only 18% inhibition of the mammary epithelial cell line MCF10A viability was observed, even at concentrations as high as 50 µM.


Asunto(s)
Antinematodos/química , Antinematodos/farmacología , Haemonchus/efectos de los fármacos , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Pirazoles/química , Pirazoles/farmacología , Animales , Línea Celular Tumoral , Evaluación Preclínica de Medicamentos , Haemonchus/crecimiento & desarrollo , Humanos , Concentración 50 Inhibidora , Fenotipo , Relación Estructura-Actividad
19.
Int J Parasitol Drugs Drug Resist ; 8(3): 379-385, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30081296

RESUMEN

Due to widespread drug resistance in parasitic nematodes, there is a need to develop new anthelmintics. Given the cost and time involved in developing a new drug, the repurposing of known chemicals can be a promising, alternative approach. In this context, we tested a library (n = 600) of natural product-inspired pesticide analogues against exsheathed third stage-larvae (xL3s) of Haemonchus contortus (barber's pole worm) using a whole-organism, phenotypic screening technique that measures the inhibition of motility and development in treated larvae. In the primary screen, we identified 32 active analogues derived from chemical scaffolds of arylpyrrole or fipronil. The seven most promising compounds, selected based on their anthelmintic activity and/or limited cytotoxicity, are arylpyrroles that reduced the motility of fourth-stage larvae (L4s) with significant potency (IC50 values ranged from 0.04 ±â€¯0.01 µM to 4.25 ±â€¯0.82 µM, and selectivity indices ranged from 10.6 to 412.5). Since the parent structures of the active compounds are uncouplers of oxidative phosphorylation, we tested the effect of selected analogues on oxygen consumption in xL3s using the Seahorse XF24 flux analyser. Larvae treated with the test compounds showed a significant increase in oxygen consumption compared with the untreated control, demonstrating their uncoupling activity. Overall, the results of the present study have identified natural product-derived molecules that are worth considering for chemical optimisation as anthelmintic drug leads.


Asunto(s)
Antihelmínticos/farmacología , Haemonchus/efectos de los fármacos , Locomoción/efectos de los fármacos , Pirazoles/farmacología , Pirroles/farmacología , Animales , Antihelmínticos/química , Antihelmínticos/aislamiento & purificación , Productos Biológicos/química , Productos Biológicos/farmacología , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Reposicionamiento de Medicamentos , Resistencia a Medicamentos , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Haemonchus/fisiología , Concentración 50 Inhibidora , Larva/efectos de los fármacos , Plaguicidas/química , Plaguicidas/farmacología , Pirroles/química , Ovinos
20.
Int J Parasitol Drugs Drug Resist ; 7(3): 286-294, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28732272

RESUMEN

The discovery and development of novel anthelmintic classes is essential to sustain the control of socioeconomically important parasitic worms of humans and animals. With the aim of offering novel, lead-like scaffolds for drug discovery, Compounds Australia released the 'Open Scaffolds' collection containing 33,999 compounds, with extensive information available on the physicochemical properties of these chemicals. In the present study, we screened 14,464 prioritised compounds from the 'Open Scaffolds' collection against the exsheathed third-stage larvae (xL3s) of Haemonchus contortus using recently developed whole-organism screening assays. We identified a hit compound, called SN00797439, which was shown to reproducibly reduce xL3 motility by ≥ 70%; this compound induced a characteristic, "coiled" xL3 phenotype (IC50 = 3.46-5.93 µM), inhibited motility of fourth-stage larvae (L4s; IC50 = 0.31-12.5 µM) and caused considerable cuticular damage to L4s in vitro. When tested on other parasitic nematodes in vitro, SN00797439 was shown to inhibit (IC50 = 3-50 µM) adults of Ancylostoma ceylanicum (hookworm) and first-stage larvae of Trichuris muris (whipworm) and eventually kill (>90%) these stages. Furthermore, this compound completely inhibited the motility of female and male adults of Brugia malayi (50-100 µM) as well as microfilariae of both B. malayi and Dirofilaria immitis (heartworm). Overall, these results show that SN00797439 acts against genetically (evolutionarily) distant parasitic nematodes i.e. H. contortus and A. ceylanicum [strongyloids] vs. B. malayi and D. immitis [filarioids] vs. T. muris [enoplid], and, thus, might offer a novel, lead-like scaffold for the development of a relatively broad-spectrum anthelmintic. Our future work will focus on assessing the activity of SN00797439 against other pathogens that cause neglected tropical diseases, optimising analogs with improved biological activities and characterising their targets.


Asunto(s)
Antihelmínticos/farmacología , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Estadios del Ciclo de Vida/efectos de los fármacos , Nematodos/efectos de los fármacos , Ancylostoma/efectos de los fármacos , Animales , Antihelmínticos/química , Antihelmínticos/aislamiento & purificación , Bioensayo/métodos , Brugia Malayi/efectos de los fármacos , Haemonchus/efectos de los fármacos , Concentración 50 Inhibidora , Larva/efectos de los fármacos , Nematodos/clasificación , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología
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