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1.
Chem Biodivers ; 21(4): e202301304, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37926683

RESUMEN

The widespread and indiscriminate use of broad-spectrum antibiotics leads to microbial resistance, which causes major problems in the treatment of infectious diseases. However, advances in nanotechnology using mushrooms have opened up new domains for the synthesis and use of nanoparticles against multidrug-resistant pathogens. Mushooms have recently attracted attention and are exploited for food and medicinal purposes. The current study focuses on the molecular identification, characterization of biologically synthesized silver nanoparticles by X-ray diffraction (XRD) spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), UV-Vis spectroscopy and scanning electron microscopy (SEM) and antibacterial analysis of extract and silver nanoparticles (AgNPs) synthesis from Ganoderma resinaceum against multidrug resistant microbes. Accurate identification of mushrooms is key in utilizing them for the benefit of humans. However, morphological identification of mushrooms is time consuming, tedious and may be prone to error. Molecular techniques are quick and reliable tools that are useful in mushroom taxonomy. Blast results showed that G. resinaceum (GU451247) obtained from Pakistan was 97 % same to the recognized G. resinaceum (GU451247) obtained from China as well as G. resinaceum (GU451247) obtained from India. The antimicrobial potential of mushroom composite and AgNPs showed high efficacy against pathogenic Staphylococcus aureus (ZOI 23 mm) K. pneumonia (ZOI 20 mm), Pseudomonas aeruginosa (ZOI 24 mm) and E. fecalis and A. baumannii (ZOI 10 mm), and multidrug resistant (MDR) A. baumannii (ZOI 24 mm). XRD evaluation revealed the crystalline composition of synthesized NPs with diameter of 45 nm. UV-Vis spectroscopy obsorption peaked of 589 nm confirmed the presence of AgNPs. SEM results showed the cubic morphology of AgNPs. The FTIR analysis of NPs obtained from G. resinaceum containing C=O as well as (O=C-H) stretching revealed presence of hydrogen, carbonyl and amide groups. The synthesized extract and AgNPs showed promising minimum inhibitory concentration (MIC) at 2 mg concentration against the MDR strains. AgNPs are observed to be efficient as they need less quantities to prevent bacterial growth. In the view of challenges for developing antimicrobial NPs of variable shape and size by various other methods, tuning nanoparticles synthesized via mushrooms can be a wonderful approach to resolve existing hurdles.


Asunto(s)
Antiinfecciosos , Nanopartículas del Metal , Humanos , Plata/farmacología , Plata/química , Nanopartículas del Metal/química , Antibacterianos/química , Antiinfecciosos/farmacología , Pruebas de Sensibilidad Microbiana , Espectroscopía Infrarroja por Transformada de Fourier , Extractos Vegetales/química
2.
Inflammopharmacology ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714603

RESUMEN

Launaea fragilis (Asso) Pau is a Cholistan desert medicinal plant. Launaea species are used as traditional remedies against various inflammatory conditions. The current research was designed to evaluate the anti-nociceptive, anti-inflammatory, and anti-arthritic potential of ethanolic extract of L. fragilis (Et-LF). The plant extract was prepared by triple maceration. GC-MS screening explored the presence of various bioactive phytoconstituents including n-tetracosanol-1, 1-heptacosanol, and n-hexadecanoic acid. DPPH assay demonstrated the antioxidant potential of Et-LF. Safety profile data indicated that Et-LF was safe up to the oral dose of 5000 mg/kg in female rats. Anti-nociceptive activity of Et-LF was assessed in hot plate method and acetic acid-induced writhing model and the results suggested that Et-LF had significant analgesic effects in both animal models. Carrageenan, histamine, and serotonin-induced edema models were used to estimate the anti-inflammatory effects of Et-LF and were found to prevent paw edema development dose dependently. The anti-arthritic effect of Et-LF was estimated in CFA-induced arthritic rat model. Treatment with Et-LF 125, 250, 500 and flurbiprofen (FP) 10 mg/kg/day significantly attenuated the paw edema, reversed the reduced body weight, and restored the altered hematological parameters in arthritic rats. Gene expression studies revealed the significant downregulation of IL-1ß, TNF-α, IL-6, NF­κB, and COX-2, and upregulation of IL-4 and IL-10 in arthritic rats treated with various doses of plant extract. Histological evaluation of ankle joints showed that Et-LF mitigated pannus formation, infiltration of inflammatory cells, and fibrous connective tissue formation in the diseased rats. Thereof, it may be concluded that the recent study demonstrated the anti-nociceptive, anti-inflammatory, and anti-arthritic effects ascribed to the signifying presence of phytoconstituents in L. fragilis.

3.
Environ Res ; 234: 116550, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37437862

RESUMEN

A facile two-step hydrothermal method was successfully used to prepare a photocatalyst Bi2WO6/WS2 heterojunction for methyl blue (MB) photodegradation. Fabricated photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy (XPS). Band gap measurements were carried out by diffuse reflectance spectroscopy (DRS). Results indicated that the prepared heterostructure photocatalyst has increased visible light absorption. Photocatalytic performance was evaluated under sunlight irradiation for methylene blue (MB) degradation as a model dye. Variations in pH (4-10), amount of catalyst (0.025-0.1 g/L), and initial MB concentrations (5-20 ppm) were carried out, whereas all prepared catalysts were used to conduct the tests with a visible spectrophotometer. Degradation activity improved with the pH increase; the optimum pH was approximately 8. Catalyst concentration is directly related to degradation efficiency and reached 93.56% with 0.075 g of the catalyst. Among tested catalysts, 0.01 Bi2WO6/WS2 has exhibited the highest activity and a degradation efficiency of 99.0% in 40 min (min) for MB. MB photodegradation follows pseudo-first-order kinetics, and obtained values of kapp were 0.0482 min-1, 0.0337 min-1, 0.0205 min-1, and 0.0087 min-1 for initial concentrations of 5 ppm, 10 ppm, 15 ppm, and 20 ppm, respectively. The catalyst was reused for six cycles with a negligible decrease in the degradation activity. Heterostructure 0.01 Bi2WO6/WS2 has exhibited a photocurrent density of 16 µA cm-2, significantly higher than 2.0 and 4.5 µA cm-2 for the pristine WS2 and Bi2WO6, respectively. The findings from these investigations may serve as a crucial stepping stone towards the remediation of polluted water facilitated by implementing such highly efficient photocatalysts.


Asunto(s)
Azul de Metileno , Luz Solar , Azul de Metileno/química , Fotólisis , Luz , Catálisis
4.
Ecotoxicology ; 32(2): 234-242, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36740648

RESUMEN

Apis mellifera is an important bee pollinating native and crop plants but its recent population decline has been linked to the use of pesticides, including fungicides that have been commonly classified as safe for bees. However, many pesticides, in addition to direct mortality cause sublethal effects, including damage to target selective honey bee organs. The midgut is the organ responsible for the digestion and absorption of nutrients and the detoxification of ingested substances, such as pesticides. This study evaluated the histopathological and cytotoxic changes in the midgut of A. mellifera workers caused by the pesticide azoxystrobin. The limit-test was performed, and a 100 µg a.i./bee dose was administered orally and midgut analyzed with light and transmission electron microscopies after 24 h and 48 h of pesticide exposure. The midgut of the control bees has a single layer of digestive cells, with spherical nuclei, nests of regenerative cells, and the lumen coated with the peritrophic matrix. The bees fed on azoxystrobin showed morphological changes, including intense cytoplasm vacuolization and cell fragments released into the gut lumen. The protein detection test showed greater staining intensity in the nests of regenerative cells after 24 h of exposure to azoxystrobin. The occurrence of damage to the midgut in A. mellifera exposed to azoxystrobin indicates that although this fungicide has been classified as low toxicity for bees, it has sublethal effects in the midgut, and effects in other organs should be investigated.


Asunto(s)
Fungicidas Industriales , Himenópteros , Plaguicidas , Abejas , Animales , Fungicidas Industriales/toxicidad , Estrobilurinas
5.
Molecules ; 28(17)2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37687119

RESUMEN

The use of natural products isolated from mushrooms against infection, cancer diseases and other oxidative-stress-related diseases is one of the cornerstones of modern medicine. Therefore, we tried to establish a combination of medicinal mushrooms and nanotechnology possibly with the field of medicine for the development of antibacterial agents against these MDR strains. The aim of the research was to understand the molecular identification, characterization and antibacterial action of Calvatia gigantea and Mycena leaiana. The identification of fruiting body species via morpho-anatomical and molecular methods was necessary to analyze the genetic variability and phylogenetic relationships of mushrooms. Phylogenetic analysis revealed that Calvatia from Hunza, Pakistan, exhibited 98% resemblance to the previously discovered Langermannia gigantean (DQ112623) and L. gigantean (LN714562) from northern Europe, and Mycena (Pakistan) showed a 97% similarity to M. leaiana (MF686520) and M. leaiana (MW448623) from the USA. UV-vis, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) were used for AgNPs' characterization. The UV-vis absorption peak of 500-600 nm indicates the AgNPs' presence. XRD results determined Calvatia gigantea AgNPs were nanocrystals and Mycena leaiana seems to be amorphous. In addition, SEM results showed the cubic morphology of C. gigantea with a diameter of 65 nm, and the FTIR spectra of fruiting body revealed the presence of functional groups-carboxyl, nitro, and hydroxyl-in AgNPs, which catalyzed the reduction of Ag+ to Ag0. Further antibacterial activity of mushrooms against MDR strains was determined via agar well diffusion assay, and Minimum Inhibitory Concentration (MIC) was estimated by qualitative experimentation using the broth dilution method. All experiments were conducted in triplicate. The results showed that the mushroom AgNPs, along with their synergy and nano-composites (with the exception of Ethyl-acetate), were shown to have zones of inhibition from 4 mm to 29 mm against multidrug-resistant pathogens such as Acinetobacter baumannii, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, Proteus mirabilis, Enterobacter cloacae and Escherichia coli. The mushroom composites were active against most of the tested microorganisms whilst the lowest MIC value (10-40 mg/mL) was recorded against MDR strains. Hence, the present study suggested the possibility of employing compounds present in mushrooms for the development of new antibacterial agents, as well as efflux pump inhibitors.


Asunto(s)
Agaricales , Antiinfecciosos , Nanopartículas del Metal , Plata/farmacología , Filogenia , Antiinfecciosos/farmacología , Antibacterianos/farmacología , Escherichia coli
6.
Plant Dis ; 2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33656359

RESUMEN

Sonchus arvensis (Asteraceae) is a traditional medicinal herb. The aerial parts are a rich source of vitamins, essential amino acids, and minerals, which may help in treatment of fever, inflammation, detoxication, and blood circulation (Li et al. 2018). In October 2018, typical rust symptoms were observed on S. arvensis leaves and stems in Buner district, Malakand division, Khyber PakhtunKhwa Province, Pakistan (34.39°N; 72.61°E). Almost 40% of leaves and stems of five S. arvensis plants displayed severe rust. The specimens were examined microscopically and compared with type specimen description in published literature (Dietel 1908; Hiratsuka et al. 1992). The fungus was identified as Puccinia crepidis-japonicae based on the characteristic of spore morphology and phylogenetic study based on the internal transcribed spacer (ITS) and large subunit (LSU) sequence data. Uredinia were amphigenous, rounded, or somewhat elliptical, naked, small patches, equally spread, brown. Urediniospores (n=30) were globose to ellipsoid, brownish yellow and measured 22.4-24.7 × 20.2-22.1 µm. Urediniospore walls were brownish orange and finely echinulate and 1.7 to 2.1 µm thick with 2 to 3 germ pores. Telia were amphigenous, rounded or elliptic, scattered, dark brown to blackish. Teliospores (n=30) were ellipsoid, subglobose or long ellipsoid, rounded at both ends, not thickened at apex, warted, reddish brown, and measured 31.3-39 × 24.6-26.8 µm. Teliospore walls were reddish-black and about 1.5-2.5 µm thick, and the pedicles were short, hyaline, fragile, become tapered toward apex, and measured 14.4-18.7 × 4.7-9 µm. DNA was extracted from urediniospores, and the combined region of ITS and LSU (28S) were amplified using Rust2Inv (forward primer) and LR6 (Reverse primer) according to the protocol outlined by Aime (2006). A BLASTn search (http://www.ncbi.nlm.nih.gov) showed that the combined ITS and LSU region shared 99% identity (792/804 bp) to the P. crepidis-japonicae accessions (KY798395 from Hawaii, USA) with 100% query cover. The resulting sequence was deposited in GenBank (Accession No. MN093335). Both morphological and molecular characteristics indicatethat this species was P. crepidis-japonicae. To test pathogenicity and fulfill the Koch's postulates, a urediniospore suspension (1 × 104 spores/ml) was sprayed on three 6-week-old plants of S. arvensis, and one as negative control, incubated at 22-24°C. Uredinia were observed on the leaves after 10 days of inoculation, whereas the control plants remained symptomless. Microscopic examination confirmed that the symptoms on plants obtained from the field and greenhouse inoculations were morphologically identical. This fungus has been observed previously on Crepis japonica in China, Hong Kong, Japan, Korea, and Taiwan, on Prenanthes spp. in China and on Youngia tenuifolia and Y. fusca in China (Farr and Rossman 2021). Pereira et al. (2002) suggested that P. crepidis-japonicae may play a significant role as a biocontrol agent against its weed host. To the best of our knowledge, there are no other reports of this fungus on any other hosts in Pakistan. The specimen has been vouchered in LAH Herbarium, Department of Botany, University of the Punjab, Lahore, Pakistan (LAH36343). This is the first report of P. crepidis-japonicae on S. arvensis as a new host from Pakistan.

7.
Physiol Mol Biol Plants ; 27(7): 1423-1436, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34366587

RESUMEN

Glycoside hydrolase (GH, EC 3.2.1) is a group of enzymes that hydrolyzes glycosidic bonds and play a role in the hydrolysis and synthesis of sugars in living organisms. Vitis vinifera is an important fruit crop and it harbors GH17 gene family however, their function in grapes has not been systematically investigated. In this study, a total of 870 GH17 genes were identified from 14 plant species and their structural domain, sequence alignment, phylogenetic tree, collinear analysis, with the expression profiles of VviGH17 gene family was performed. The promoter analysis of VviGH17 gene showed the presence of cis-acting elements, which are responsive to plant growth and development. In addition, elements for plant hormones were found that are triggered in response to abiotic/biological stress. Transcriptomic data led to the identification of several VviGH17 genes, which are associated with bud dormancy and in response to abiotic stress. Transcript analysis was carried out for some of the selected VviGH17 genes RT-qPCR. VviGH17-16 and VviGH17-30 genes were differentially expressed during bud dormancy, fruit development and different abiotic stresses. Moreover, VviGH17-37 and VviGH17-44 were differentially expressed at fruit development, in response to abiotic stress. In addition, subcellular localization predicts that the VviGH17-16, VviGH17-30, and VviGH17-37 genes were located in the cell membrane, while VviGH17-44 gene was located in the vacuole. In conclusion, our study led to the identification of several GH17s and their probable role in development and stress. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-021-01014-1.

8.
Cell Tissue Res ; 382(2): 337-349, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32447450

RESUMEN

The burrower bug Scaptocoris castanea is an important soybean and pasture pest in Brazil, with an underground habit feeding directly on the sap of the roots. Underground habit hinders control and knowledge of the biology and physiology of this pest. This study describes the anatomy, histology, ultrastructure and symbionts of the midgut of S. castanea. The midgut of S. castanea is anatomically divided into five regions (ventricles). Ventricles 1-3 are similar between males and females, with cells specialized in digestion and absorption of nutrients, water transport and homeostasis. Ventricle 4 has squamous epithelium forming crypts and harboring bacteria in the lumen. Ventricle 5 of males is small with cells containing apical microvilli and broad basal folds with many openings for hemocoel, while in females, this region of the midgut is well developed and colonized by intracellular bacteria, characterizing bacteriocytes. The main bacteria are Gammaproteobacteria. The results show sexual dimorphism in ventricle 5 of the midgut of S. castanea, with formation of bacteriocytes in the females, while the other regions are involved in digestive processes in both sexes.


Asunto(s)
Bacterias/patogenicidad , Hemípteros/microbiología , Microbiota/fisiología , Animales , Femenino , Masculino
9.
Microsc Microanal ; 26(6): 1236-1244, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32924896

RESUMEN

The carpenter ant Camponotus rufipes has intracellular bacteria in bacteriocytes scattered in the midgut epithelium, which have different amounts of endosymbionts, according to the developmental stages. However, there are no detailed data about the midgut cells in adult workers. The present work aimed to evaluate the morphology and cellular events that coordinate the abundance of endosymbionts in the midgut cells in C. rufipes workers. The midgut epithelium has digestive cells, bacteriocytes, and cells with intermediate morphology. The latter is similar to bacteriocytes, due to the abundance of endosymbionts, and similar to digestive cells, due to their microvilli. The digestive and intermediate cells are rich in autophagosomes and autolysosomes, both with bacteria debris in the lumen. These findings suggest that midgut cells of C. rufipes control the endosymbiont level by the autophagy pathway.


Asunto(s)
Hormigas , Animales , Autofagia , Bacterias , Humanos , Simbiosis
10.
Chaos Solitons Fractals ; 137: 109874, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32454569

RESUMEN

A drone based on four rotors is considered in this research paper. Its chaotic solution is shown bounded in an inscribed sphere whose vertices are tangent to faces of octahedron. Based on concept of constrained optimization; Linear Matrix Inequalities (LMIs) satisfying quadratic constraint increment multiplier matrix σm , state observers and descriptors with estimated parameter is calculated. Moreover, an image file is decrypted by designing description for mentioned chaotic system and then encrypted on its receiver end. Furthermore, an electric circuit is designed for chaotic quadrotor using LTspice and is fitted into wireless flying robot to observe its dynamics in bounded rectangular region.

11.
Ecotoxicology ; 28(7): 763-770, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31254186

RESUMEN

Euschistus heros (F.) (Hemiptera: Pentatomidae) is a soybean pest in Brazil, controlled with synthetic chemical insecticides, which may be harmful to the environment and humans, as well as to select pest resistant strains. The research for new pest control strategies such as the use of plant essential oils has been increased due to the selectivity and biodegradation of these molecules. The objective was to evaluate the cytological changes in the salivary glands, fat body and midgut of E. heros exposed to different concentrations of essential oil of Piper aduncum L. (Piperales: Piperaceae), which the main compounds were identified as myristicin 30.03%, aromadendrene 9.20%, dillapiole 8.43%, α-serinene 7.31%, tridecane 6.26%, γ-elemene 4.58% and o-cymene 4.20%. The essential oil of P. aduncum was toxic for E. heros with LD50 = 36.23 mg per insect and LD90 = 50.42 mg per insect. Cytological changes such as tissue disruption, increase in mitochondria population, and glycogen and lipid depletion occur in the fat body cells, whereas salivary glands and midgut are not affected by this essential oil. Results suggest that P. aduncum essential oil causes fat body cellular stress, which may compromise some physiological processes for the insect survival.


Asunto(s)
Cuerpo Adiposo/efectos de los fármacos , Heterópteros/efectos de los fármacos , Aceites Volátiles/toxicidad , Piper/química , Animales , Relación Dosis-Respuesta a Droga , Tracto Gastrointestinal/efectos de los fármacos , Heterópteros/crecimiento & desarrollo , Dosificación Letal Mediana , Ninfa/efectos de los fármacos , Ninfa/crecimiento & desarrollo , Aceites Volátiles/química , Glándulas Salivales/efectos de los fármacos
12.
Microsc Microanal ; 25(6): 1482-1490, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31571553

RESUMEN

The burrower bug Scaptocoris castanea Perty, 1830 (Hemiptera: Cydnidae) is an agricultural pest feeding on roots of several crops. The histology and ultrastructure of the salivary glands of S. castanea were described. The salivary system has a pair of principal salivary glands and a pair of accessory salivary glands. The principal salivary gland is bilobed with anterior and posterior lobes joined by a hilus where an excretory duct occurs. The accessory salivary gland is tubular with a narrow lumen that opens into the hilus near the excretory duct, suggesting that its secretion is stored in the lumen of the principal gland. The cytoplasm of the secretory cells is rich in the rough endoplasmic reticulum, secretory vesicles with different electron densities and mitochondria. At the base of the accessory gland epithelium, there were scattered cells that do not reach the gland lumen, with the cytoplasm rich in the rough endoplasmic reticulum, indicating a role in protein production. Data show that principal and accessory salivary glands of S. castanea produce proteinaceous saliva. This is the first morphological description of the S. castanea salivary system that is similar to other Hemiptera Pentatomomorpha, but with occurrence of basal cells in the accessory salivary gland.


Asunto(s)
Heterópteros , Glándulas Salivales/anatomía & histología , Glándulas Salivales/ultraestructura , Animales , Células Epiteliales/ultraestructura , Histocitoquímica , Microscopía , Microscopía Electrónica , Orgánulos/ultraestructura , Saliva/química , Glándulas Salivales/química , Proteínas y Péptidos Salivales/análisis
13.
J Pak Med Assoc ; 69(3): 301-305, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30890818

RESUMEN

OBJECTIVE: To explore the association of rs662799 variants of Apolipoprotein A5 gene with metabolic syndrome in Pakistani population. METHODS: The case-control study was conducted at Pakistan Institute of Medical Sciences, Islamabad, Pakistan from 2014 to2016, and comprised subjects enrolled from the out-patient clinics. Groups were formed on the basis of preliminary screening for risk factors like obesity, insulin resistance, hypertension, dyslipidemia and fasting blood glucose levels. Met S was diagnosed based on the international diabetes federation criteria. Blood samples were collected for biochemical testing and deoxyribonucleic acid extraction. Genotyping of rs662799 was performed a the Genome Research Centre of the University of Hong Kong using Sequenom Mass ARRAY, iPLEX Gold technology. Data was analysed using SPSS 16and Plink software. RESULTS: :There were 712 subjects in two groups of 356(50%) each. The overall mean age was 41.59}7.18 years. There was a significant association of risk allele C of rs662799 with metabolic syndrome (p=0.002). The risk showed strong association with dyslipidaemia (p=0.03) and obesity (p=0.01) which are risk phenotypes of metabolic syndrome in age- and gender-adjusted model. CONCLUSIONS: The association of risk allele C of genetic variant rs662799 of Apolipoprotein A5 gene with dyslipidaemia and obesity may lead to the development of metabolic syndrome in the Pakistan adult population.


Asunto(s)
Apolipoproteína A-V/genética , Dislipidemias/genética , Síndrome Metabólico/genética , Obesidad/genética , Adulto , Femenino , Predisposición Genética a la Enfermedad , Variación Genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Pakistán , Polimorfismo de Nucleótido Simple
14.
Appl Opt ; 57(27): 7830-7836, 2018 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-30462049

RESUMEN

An investigation is presented for the reduction of cross-polarized Gaussian beam scattering from a perfect electromagnetic conducting (PEMC) cylinder coated with topological insulator (TI) material and buried in a semi-infinite medium. To calculate the successive reflections of the scattered field from the interface, cylindrical wave functions are written into the spectrum of plane waves. The scattered reflected field is calculated for each plane wave of the spectrum. Near- and far-zone scattered fields are reported for time-reversal symmetry and symmetry-broken TI coating. It is observed that the near-zone scattered field is very helpful to understand why the scattering width (SW) of a cylinder coated with time-reversal symmetry TI material is different from the SW of a cylinder coated with symmetry-broken TI material. The effect of spot size of the Gaussian beam on the scattering pattern is investigated, while the result for a plane wave is served as a reference. It is observed that cross-polarized scattering can be reduced by increasing the thickness of the coating layer. It also decreases as admittance of the PEMC core increases. Moreover, the cross-polarized scattered field becomes significantly small when time-reversal symmetry is broken, irrespective of PEMC or perfect electric conductor (PEC) core.

15.
Ecotoxicol Environ Saf ; 156: 1-8, 2018 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-29524778

RESUMEN

Annonaceous acetogenins (Annona squamosa Linnaeus) comprises of a series of natural products which are extracted from Annonaceae species, squamocin proved to be highly efficient among those agents. Squamocin is mostly referred as a lethal agent for midgut cells of different insects, with toxic effects when tested against larva of some insects. In present study, LC50 and LC90 of squamocin for A. gemmatalis Hübner (Lepidoptera: Noctuidae) were calculated using probit analysis. Morphological changes in midgut cells were analyzed under light, fluorescence and transmission electron microscopes when larvae were treated with LC50 and LC90 of squamocin for 24, 48 and 72 h. Results revealed that the maximum damage to midgut cells was found under LC90 where it showed digestive cells with enlarged basal labyrinth, highly vacuolated cytoplasm, damaged apical surface, cell protrusions to the gut lumen, autophagy and cell death. The midgut goblet cells showed a strong disorganization of their microvilli. Likewise, in insects treated with squamocin, mitochondria were not marked with Mitotracker fluorescent probe, suggesting some molecular damage in these organelles, which was reinforced by decrease in the respiration rate in these insects. These results demonstrate that squamocin has potential to induce enough morphological changes in midgut through epithelial cell damage in A. gemmatalis.


Asunto(s)
Furanos/toxicidad , Lactonas/toxicidad , Lepidópteros/efectos de los fármacos , Animales , Autofagia , Sistema Digestivo/anatomía & histología , Sistema Digestivo/efectos de los fármacos , Sistema Digestivo/ultraestructura , Larva/anatomía & histología , Larva/efectos de los fármacos , Larva/ultraestructura , Lepidópteros/anatomía & histología , Lepidópteros/crecimiento & desarrollo , Lepidópteros/ultraestructura
16.
Int J Mol Sci ; 19(12)2018 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-30545146

RESUMEN

Salinity is ubiquitous abiotic stress factor limiting viticulture productivity worldwide. However, the grapevine is vulnerable to salt stress, which severely affects growth and development of the vine. Hence, it is crucial to delve into the salt resistance mechanism and screen out salt-resistance prediction marker genes; we implicated RNA-sequence (RNA-seq) technology to compare the grapevine transcriptome profile to salt stress. Results showed 2472 differentially-expressed genes (DEGs) in total in salt-responsive grapevine leaves, including 1067 up-regulated and 1405 down-regulated DEGs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations suggested that many DEGs were involved in various defense-related biological pathways, including ROS scavenging, ion transportation, heat shock proteins (HSPs), pathogenesis-related proteins (PRs) and hormone signaling. Furthermore, many DEGs were encoded transcription factors (TFs) and essential regulatory proteins involved in signal transduction by regulating the salt resistance-related genes in grapevine. The antioxidant enzyme analysis showed that salt stress significantly affected the superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and glutathione S-transferase (GST) activities in grapevine leaves. Moreover, the uptake and distribution of sodium (Na⁺), potassium (K⁺) and chlorine (Cl-) in source and sink tissues of grapevine was significantly affected by salt stress. Finally, the qRT-PCR analysis of DE validated the data and findings were significantly consistent with RNA-seq data, which further assisted in the selection of salt stress-responsive candidate genes in grapevine. This study contributes in new perspicacity into the underlying molecular mechanism of grapevine salt stress-tolerance at the transcriptome level and explore new approaches to applying the gene information in genetic engineering and breeding purposes.


Asunto(s)
Perfilación de la Expresión Génica , Estrés Salino/genética , Análisis de Secuencia de ARN , Vitis/genética , Vitis/fisiología , Depuradores de Radicales Libres/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Ontología de Genes , Genes de Plantas , Proteínas de Choque Térmico/metabolismo , Transporte Iónico/efectos de los fármacos , Anotación de Secuencia Molecular , Fotosíntesis/efectos de los fármacos , Fotosíntesis/genética , Reguladores del Crecimiento de las Plantas/farmacología , Proteínas de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Reproducibilidad de los Resultados , Estrés Salino/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Factores de Transcripción/metabolismo , Vitis/efectos de los fármacos
17.
J Pak Med Assoc ; 67(12): 1825-1832, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29256524

RESUMEN

OBJECTIVE: To estimate frequencies of metabolic risk phenotypes and their associations in body mass index and waist circumference-based obesity categories. METHODS: The cross-sectional study was conducted at Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Pakistan, from August 2014 to March 2016. Anthropometric and clinical data of young adults was collected. All subjects were categorised into body mass index, waist circumference-based obesity categories and common metabolic risk phenotypes (hypertension, hyperglycaemia, dyslipidaemia) frequencies and their associations were estimated in age and gender adjusted models. Data was analysed using SPSS 21. RESULTS: Of the 2,000 participants, 800(40%) were females and 1,200(60%) were males. There were 500(25%) participants in each group, i.e. underweight, normal weight, overweight and obese. The overall mean age was 23.68±4.33 years (range: 16-30 years). All clinical parameters were significantly raised in general and abdominally obese class (p<0.05). Based on body mass index and waist circumference, the frequency of general obesity was 324(16.2%) and abdominal obesity was 994(49.7%). Co-morbid metabolic risk phenotypes were as follows: hypertension 1,098(54.9%) and 924(46.2%); hyperglycaemia 1,116(55.8%) and 550(27.5%); dyslipidaemia 300(15%) and 194(9.7%), respectively. The strongest associations of body mass index and waist circumference alone catergorised obesity were found with hyperglycaemia, (Odds ratio: 7.23, 6.49) followed by dyslipidemia (Odds ratio: 5.60, 5.67) and hypertension (Odds ratio: 3.28, 3.02). . CONCLUSIONS: Body mass index and waist circumference were found to be powerful, discriminating predictors of co-morbidities linked with general and abdominal obesity.


Asunto(s)
Índice de Masa Corporal , Diabetes Mellitus Tipo 2/epidemiología , Obesidad/epidemiología , Circunferencia de la Cintura/fisiología , Adolescente , Adulto , Antropometría , Enfermedades Cardiovasculares/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Pakistán/epidemiología , Factores de Riesgo , Adulto Joven
18.
Avian Pathol ; 44(4): 305-10, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25932659

RESUMEN

The study was conducted to investigate the role of aflatoxin on the infectivity and transmissibility of H9N2 AI virus. The experiment was performed on 80 non-vaccinated turkeys, divided into 4 groups of 20 birds each. Group A was kept as non-infected and a non-treated negative control; Group B was inoculated intratracheally with H9N2 AI virus (1 × 10(7) EID50) at 4 weeks of age; Group C was fed on a diet containing 0.5 ppm aflatoxin from Day 1 through the entire experiment period and Group D was fed on diet containing 0.5 ppm aflatoxin as for Group C but inoculated intratracheally with H9N2 AI virus (1 × 10(7) EID50) at the fourth week of age and then mixed with naïve birds. Infected and contact birds showed clinical signs of different severity, showing the most prominent disease signs in birds of the aflatoxin + H9N2 group. All infected birds showed virus shedding, however, the pattern of virus shedding was different for birds of the aflatoxin + H9N2 group showing pronounced virus secretion. Similarly, efficient transmission of virus was observed between infected and contact birds, but more prominent virus transmission was seen in those birds inoculated and fed aflatoxin-treated diet. Moreover, significantly lower antibody titres against H9N2 AIV were observed in birds fed aflatoxin-treated diet, indicating an immunotoxic nature of aflatoxin as the reason for poor seroconversion. Similarly, decreased IFNγ mRNA expression and higher mortality (35%) suggest an immunotoxic and immunosuppressive effect of aflatoxin leading to enhanced pathogenesis of H9N2 viruses in aflatoxin-fed birds. The immunosuppressive nature of aflatoxin might delay influenza virus clearance and this may be one of the reasons for increased pathogenicity of H9N2 LPAI viruses in turkeys under field conditions.


Asunto(s)
Aflatoxinas/toxicidad , Subtipo H9N2 del Virus de la Influenza A/efectos de los fármacos , Gripe Aviar/virología , Enfermedades de las Aves de Corral/virología , Pavos/virología , Animales , Subtipo H9N2 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/patogenicidad , Gripe Aviar/transmisión , Enfermedades de las Aves de Corral/transmisión , Virulencia , Esparcimiento de Virus
19.
Mol Ecol ; 23(3): 603-17, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24354737

RESUMEN

Understanding the mode of temporal maintenance of plant pathogens is an important domain of microbial ecology research. Due to the inconspicuous nature of microbes, their temporal maintenance cannot be studied directly through tracking individuals and their progeny. Here, we suggest a series of population genetic analyses on molecular marker variation in temporally spaced samples to infer about the relative contribution of sexual reproduction, off-season survival and migration to the temporal maintenance of pathogen populations. We used the proposed approach to investigate the temporal maintenance of wheat yellow rust pathogen, Puccinia striiformis f.sp. tritici (PST), in the Himalayan region of Pakistan. Multilocus microsatellite genotyping of PST isolates revealed high genotypic diversity and recombinant population structure across all locations, confirming the existence of sexual reproduction in this region. The genotypes were assigned to four genetic groups, revealing a clear differentiation between zones with and without Berberis spp., the alternate host of PST, with an additional subdivision within the Berberis zone. The lack of any differentiation between samples across two sampling years, and the very infrequent resampling of multilocus genotypes over years at a given location was consistent with limited over-year clonal survival, and a limited genetic drift. The off-season oversummering population in the Berberis zone, likely to be maintained locally, served as a source of migrants contributing to the temporal maintenance in the non-Berberis zone. Our study hence demonstrated the contribution of both sexual recombination and off-season oversummering survival to the temporal maintenance of the pathogen. These new insights into the population biology of PST highlight the general usefulness of the analytical approach proposed.


Asunto(s)
Basidiomycota/genética , Genética de Población , Enfermedades de las Plantas/microbiología , Triticum/microbiología , Teorema de Bayes , Berberis/microbiología , Análisis por Conglomerados , ADN de Hongos/genética , Variación Genética , Genotipo , Repeticiones de Microsatélite , Tipificación de Secuencias Multilocus , Pakistán , Densidad de Población , Estaciones del Año , Análisis de Secuencia de ADN
20.
J Opt Soc Am A Opt Image Sci Vis ; 31(1): 26-34, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24561936

RESUMEN

A two-dimensional beam is scattered by a cylinder buried below a slightly rough surface. The cylindrical wave approach is applied, i.e., cylindrical waves are employed as basis functions of the fields scattered by the cylinder. Moreover, a spectral representation of both the incident field and the cylindrical waves is used. Rough surface deviation is coped with by the first-order small perturbation method. Therefore, to a zeroth-order solution relevant to scattering in the case of a flat surface, a first-order approximation is superimposed. The theoretical approach has been implemented for a periodic surface with Gaussian roughness spectrum.

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