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1.
J Hered ; 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37897187

RESUMO

Among the three main divergent lineages of gray wolf (Canis lupus), the Holarctic lineage is the most widespread and best-studied, particularly in North America and Europe. Less is known about Tibetan (also called Himalayan) and Indian wolf lineages in southern Asia, especially in areas surrounding Pakistan where all three lineages are thought to meet. Given the endangered status of the Indian wolf in neighboring India and unclear southwestern boundary of the Tibetan wolf range, we conducted mitochondrial and genome-wide sequencing of wolves from Pakistan and Kyrgyzstan. Sequences of the mitochondrial D-loop region of 81 wolves from Pakistan indicated contact zones between Holarctic and Indian lineages across the northern and western mountains of Pakistan. Reduced-representation genome sequencing of 8 wolves indicated an east-to-west cline of Indian to Holarctic ancestry, consistent with a contact zone between these two lineages in Pakistan. The western boundary of the Tibetan lineage corresponded to the Ladakh region of India's Himalayas with a narrow zone of admixture spanning this boundary from the Karakoram Mountains of northern Pakistan into Ladakh, India. Our results highlight the conservation significance of Pakistan's wolf populations, especially the remaining populations in Sindh and Southern Punjab that represent the highly endangered Indian lineage.

2.
PeerJ ; 11: e14741, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846462

RESUMO

Niche overlap between sympatric species can indicate the extent of interspecific competition. Sympatric competing species can exhibit spatial, temporal, and dietary adjustments to reduce competition. We investigated spatial, temporal, and dietary niche overlap of sympatric Asian palm civet (Paradoxurus hermaphroditus) and small Indian civet ( Viverricula indica), in and around Pir Lasura National Park, Pakistan. We used remote cameras to determine the frequency and timing of detections to estimate spatial and temporal overlap, and prey remains from scats to estimate dietary overlap. We collected scat samples of Asian palm civet (n = 108) and small Indian civet (n = 44) for dietary analysis. We found low spatial (Oij = 0.32) and temporal (Δ = 0.39) overlap, but high dietary niche overlap (0.9) between these two civet species. Both civet species were detected at only 11 camera sites and small Indian civets were detected most frequently during 2:00-5:00 h and 8:00-10:00 h, whereas Asian palm civets detections were greatest during 20:00-2:00 h. The overall niche breadth of Asian palm civet was slightly narrower (L = 9.69, Lst = 0.31) than that of the small Indian civet (L = 10, Lst = 0.52). We identified 27 dietary items (15 plant, 12 animal) from scats of Asian palm civet including Himalayan pear (Pyrus pashia; 27%), Indian gerbil (Tatera indica; 10%), Rhesus monkey (Macaca mulatta; 4%), and insects (5%). Scat analysis of small Indian civets revealed 17 prey items (eight plant, nine animal) including Himalayan pear (24%), domestic poultry (15%), Indian gerbil (11%), and house mouse (Mus musculus; 5%). Both civet species consumed fruits of cultivated orchard species. Spatial and temporal partitioning of landscapes containing diverse foods appears to facilitate coexistence between Asian palm civets and small Indian civets.


Assuntos
Simpatria , Viverridae , Animais , Camundongos , Paquistão , Gerbillinae
3.
J Colloid Interface Sci ; 631(Pt B): 258-268, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36403381

RESUMO

The photocatalytic degradation of conventional and emerging pollutants (i.e., methyl, ethyl, and butyl parabens) was investigated under light irradiation with 315-1050 nm wavelength using core-shell zinc doped hexacyanoferrate@Prussian blue nanoparticles. Different synthesis parameters including precursors loading, drying temperature and different metal ions precursors were studied. The ten different composite systems obtained, were investigated for the photodegradation of methylene blue in deionized water. The optimal performance photocatalyst (20 mg/L) photodegrade 94% of 10 ppm methylene blue within 24 min. The optimized sample was further used for the photodegradation of methylene blue in municipal wastewater matrix; it completely degraded the methylene blue after 51 min. Finally, the developed nanoparticles were investigated for the photodegradation of parabens. The chemical oxygen demand showed 30% of parabens was degraded in the municipal wastewater matrix. The results of this research show that ZnHCF@PB nanoparticles could be used for the effective photocatalytic remediation of conventional and emerging pollutants, i.e., parabens. STATEMENT OF ENVIRONMENTAL IMPLICATION: Through this study, it is anticipated that ZnO-derived ZnHCF@PB NPs can achieve a bandgap of 1.11 eV, which is much lower than that of ZnO NPs (3.15 eV). Interestingly, ZnHCF@PB NPs were efficiently used for the degradation of conventional (i.e., dyes) and emerging contaminants (i.e., parabens) in deionized water and municipal wastewater matrices to mimic industrial wastewater.


Assuntos
Poluentes Ambientais , Nanopartículas , Óxido de Zinco , Água , Azul de Metileno , Parabenos , Águas Residuárias
4.
Cureus ; 15(12): e51351, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38288195

RESUMO

Diabetic retinopathy (DR) is a leading cause of global visual impairment, necessitating a comprehensive understanding of its vascular and neural components for effective therapeutic interventions. While vascular pathology is well-established, recent evidence suggests a neurodegenerative role in DR. Vascular endothelial growth factor (VEGF), traditionally implicated in angiogenesis, has emerged as a key player with neuroprotective potential. This systematic review evaluates the literature to shed light on molecular mechanisms and clinical implications in this regard. The review adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, encompassing a thorough search strategy across multiple databases. Three in vitro studies met the inclusion criteria, highlighting the limited research in this evolving field. Findings suggest VEGF's neuroprotective effects on retinal ganglion cells (RGCs) and retinal neurons, unveiling potential therapeutic avenues. However, concerns arise regarding anti-VEGF therapies' impact on RGC survival. The review discusses the need for further research to delineate specific isoforms and signaling pathways responsible for VEGF-mediated neuroprotection. The delicate balance between angiogenesis and neuroprotection poses challenges in therapeutic development, emphasizing the importance of targeted interventions. Despite limitations, this review provides valuable insights into the intricate relationship between VEGF and neuroprotection in DR, paving the way for future investigations and redefining therapeutic strategies.

5.
Front Genet ; 13: 988256, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338987

RESUMO

The widespread impacts of projected global and regional climate change on rice yield have been investigated by different indirect approaches utilizing various simulation models. However, direct approaches to assess the impacts of climatic variabilities on rice growth and development may provide more reliable evidence to evaluate the effects of climate change on rice productivity. Climate change has substantially impacted rice production in the mid-high latitudes of China, especially in Northeast China (NEC). Climatic variabilities occurring in NEC since the 1970s have resulted in an obvious warming trend, which made this region one of the three major rice-growing regions in China. However, the projections of future climate change have indicated the likelihood of more abrupt and irregular climatic changes, posing threats to rice sustainability in this region. Hence, understanding the self-adaptability and identifying adjustive measures to climate variability in high latitudes has practical significance for establishing a sustainable rice system to sustain future food security in China. A well-managed field study under randomized complete block design (RCBD) was conducted in 2017 and 2018 at two study sites in Harbin and Qiqihar, located in Heilongjiang province in NEC. Four different cultivars were evaluated: Longdao-18, Longdao-21 (longer growth duration), Longjing-21, and Suijing-18 (shorter growth duration) to assess the inter-relationships among grain-filling parameters, grain yield and yield components, and grain quality attributes. To better compare the adaptability mechanisms between grain-filling and yield components, the filling phase was divided into three sub-phases (start, middle, and late). The current study evaluated the formation and accumulation of the assimilates in superior and inferior grains during grain-filling, mainly in the middle sub-phase, which accounted for 59.60% of the yield. The grain yields for Suijing-18, Longjing-21, Longdao-21, and Longdao-18 were 8.02%, 12.78%, 17.19%, and 20.53% higher in Harbin than those in Qiqihar, respectively in 2017, with a similar trend observed in 2018. At Harbin, a higher number of productive tillers was noticed in Suijing-18, with averages of 17 and 15 in 2017 and 2018, respectively. The grain-filling parameters of yield analysis showed that the filling duration in Harbin was conducive to increased yield but the low dry weight of inferior grains was a main factor limiting the yield in Qiqihar. The average protein content values in Harbin were significantly higher (8.54% and 9.13%) than those in Qiqihar (8.34% and 9.14%) in 2017 and 2018, respectively. The amylose content was significantly higher in Harbin (20.03% and 22.27%) than those in Qiqihar (14.44% and 14.67%) in 2017 and 2018, respectively. The chalkiness percentage was higher in Qiqihar, indicating that Harbin produced good quality rice. This study provides more direct evidence of the relative changes in rice grain yield due to changes in grain-filling associated with relative changes in environmental components. These self-adaptability mechanisms to climatic variability and the inter-relationships between grain-filling and grain yield underscore the urgent to investigate and explore measures to improve Japonica rice sustainability, with better adaptation to increasing climatic variabilities. These findings may also be a reference for other global rice regions at high latitudes in addressing the impacts of climate change on future rice sustainability.

6.
Front Plant Sci ; 13: 960641, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092421

RESUMO

Rice (Oryza sativa L.) is considered as a staple food for more than half of the global population, and sustaining productivity under a scarcity of resources is challenging to meet the future food demands of the inflating global population. The aerobic rice system can be considered as a transformational replacement for traditional rice, but the widespread adaptation of this innovative approach has been challenged due to higher losses of nitrogen (N) and reduced N-use efficiency (NUE). For normal growth and developmental processes in crop plants, N is required in higher amounts. N is a mineral nutrient and an important constituent of amino acids, nucleic acids, and many photosynthetic metabolites, and hence is essential for normal plant growth and metabolism. Excessive application of N fertilizers improves aerobic rice growth and yield, but compromises economic and environmental sustainability. Irregular and uncontrolled use of N fertilizers have elevated several environmental issues linked to higher N losses in the form of nitrous oxide (N2O), ammonia (NH3), and nitrate (NO3 -), thereby threatening environmental sustainability due to higher warming potential, ozone depletion capacities, and abilities to eutrophicate the water resources. Hence, enhancing NUE in aerobic rice has become an urgent need for the development of a sustainable production system. This article was designed to investigate the major challenge of low NUE and evaluate recent advances in pathways of the N cycle under the aerobic rice system, and thereby suggest the agronomic management approaches to improve NUE. The major objective of this review is about optimizing the application of N inputs while sustaining rice productivity and ensuring environmental safety. This review elaborates that different soil conditions significantly shift the N dynamics via changes in major pathways of the N cycle and comprehensively reviews the facts why N losses are high under the aerobic rice system, which factors hinder in attaining high NUE, and how it can become an eco-efficient production system through agronomic managements. Moreover, it explores the interactive mechanisms of how proper management of N cycle pathways can be accomplished via optimized N fertilizer amendments. Meanwhile, this study suggests several agricultural and agronomic approaches, such as site-specific N management, integrated nutrient management (INM), and incorporation of N fertilizers with enhanced use efficiency that may interactively improve the NUE and thereby plant N uptake in the aerobic rice system. Additionally, resource conservation practices, such as plant residue management, green manuring, improved genetic breeding, and precision farming, are essential to enhance NUE. Deep insights into the recent advances in the pathways of the N cycle under the aerobic rice system necessarily suggest the incorporation of the suggested agronomic adjustments to reduce N losses and enhance NUE while sustaining rice productivity and environmental safety. Future research on N dynamics is encouraged under the aerobic rice system focusing on the interactive evaluation of shifts among activities and diversity in microbial communities, NUE, and plant demands while applying N management measures, which is necessary for its widespread adaptation in face of the projected climate change and scarcity of resources.

7.
J Colloid Interface Sci ; 621: 440-463, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35483177

RESUMO

Zinc oxide nanoparticles (ZnO NPs) are important semiconductor materials with interesting photo-responsive properties. During the past, ZnO-based NPs have received considerable attention for photodynamic therapy (PDT) due to their biocompatibility and excellent potential of generating tumor-killing reactive oxygen species (ROS) through gentle photodynamic activation. This article provides a comprehensive review of the recent developments and improvements in optical properties of ZnO NPs as photosensitizers for PDT. The optical properties of ZnO-based photosensitizers are significantly dependent on their charge separation, absorption potential, band gap engineering, and surface area, which can be adjusted/tuned by doping, compositing, and morphology control. Here, we first summarize the recent progress in the charge separation capability, absorption potential, band gap engineering, and surface area of nanosized ZnO-based photosensitizers. Then, morphology control that is closely related to their synthesis method is discussed. Following on, the state-of-art for the ZnO-based NPs in the treatment of hypoxic tumors is comprehensively reviewed. Finally, we provide some outlooks on common targeted therapy methods for more effective tumor killing, including the attachment of small molecules, antibodies, ligands molecules, and receptors to NPs which further improve their selective distribution and targeting, hence improving the therapeutic effectiveness. The current review may provide useful guidance for the researchers who are interested in this promising dynamic cancer treatment technology.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Óxido de Zinco , Humanos , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Óxido de Zinco/farmacologia
8.
J Colloid Interface Sci ; 614: 538-546, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35121512

RESUMO

Semiconducting zinc oxide nanoparticles (ZnO NPs) hold great potential as photocatalysts in wastewater treatment because of their favorable bandgap and cost-effectiveness. Unfortunately, ZnO NPs usually show rapid charge recombination that limits their photocatalytic efficacy significantly. Herein, we report a facile way of modifying ZnO NPs with zeolite imidazole framework-8 (ZIF8). A synergy between the two components may tackle the drawback of fast charge recombination for pristine ZnO NPs. Improved performance of photocatalytic degradation of methylene blue (MB) is confirmed by comparing with pristine ZnO and ZIF8 as the catalysts. The ZIF8 in the composite serves as a trap for photogenerated electrons, thus reducing the rate of charge recombination to enhance the photocatalysis rate. In addition, the hybridization process suppresses the aggregation of ZnO NPs, providing a large surface area and a greater number of active sites. Moreover, a small shift in the absorption band of ZnO@ZIF8 (10) NPs towards higher wavelength, also witnessed a little contribution towards enhanced photocatalytic properties. Mechanistic studies of the photocatalytic process of MB using ZnO@ZIF8 NPs catalyst reveal that hydroxyl radicals are the major reactive oxygen species. The facile hybridization of ZnO with ZIF8 provides a strategy for developing new photocatalysts with wide application potential.


Assuntos
Nanopartículas , Zeolitas , Óxido de Zinco , Imidazóis , Recombinação Genética , Óxido de Zinco/química
9.
Zool Stud ; 60: e34, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34963787

RESUMO

The leopard cat (Prionailurus bengalensis) is distributed throughout the Himalayan foothills in Pakistan and occurs in moist temperate and dry coniferous forests. However, the cat species is categorized as "Data Deficient" in Pakistan. In the current study we aimed to investigate the leopard cat distribution and dietary niche in the Margalla Hills National Park, the lowest part of the Himalayan foothills in Pakistan. We recorded direct (field observations, camera trapping) and indirect signs (scats) of the species on 23 trails /tracks in the study area. The leopard cat was recorded at 13 different sampling sites in the park, with an altitudinal range between 664-1441 m asl. The diet composition of the species was investigated through scat analysis, with the species identity of the scats confirmed through the mitochondrial cytB region. The species' diet comprised both animal and plant matter. The animal-based diet (in terms of frequency of occurrence) contained wild (51.75%) as well as domestic prey (7.69%), and plant species (31.47%). Wild prey included small mammals (rodents, two mongoose species, Asian palm squirrel, and Cape hare), birds, insects and snails. The domestic prey were poultry birds, sheep, goats and dogs. Consumption of wild prey was higher in summer (n = 31 scat), whereas intake of domestic prey was higher in winter (n = 37 scats). The dietary niche breadth was wider 14.84 in summer than winter 10.67. A chi-square test showed a significant difference in seasonal dietary intake of the leopard cat. The study concludes that the leopard cat feeds mainly on wild animal prey and plant species; however, in winter consumption of domestic prey increases.

10.
Nanomaterials (Basel) ; 11(5)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062851

RESUMO

The activation of magnetic nanoparticles in hyperthermia treatment by an external alternating magnetic field is a promising technique for targeted cancer therapy. The external alternating magnetic field generates heat in the tumor area, which is utilized to kill cancerous cells. Depending on the tumor type and site to be targeted, various types of magnetic nanoparticles, with variable coating materials of different shape and surface charge, have been developed. The tunable physical and chemical properties of magnetic nanoparticles enhance their heating efficiency. Moreover, heating efficiency is directly related with the product values of the applied magnetic field and frequency. Protein corona formation is another important parameter affecting the heating efficiency of MNPs in magnetic hyperthermia. This review provides the basics of magnetic hyperthermia, mechanisms of heat losses, thermal doses for hyperthermia therapy, and strategies to improve heating efficiency. The purpose of this review is to build a bridge between the synthesis/coating of magnetic nanoparticles and their practical application in magnetic hyperthermia.

11.
PeerJ ; 9: e10738, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33628635

RESUMO

Ecosystem functioning is dependent a lot on large mammals, which are, however, vulnerable and facing extinction risks due to human impacts mainly. Megafauna of Asia has been declining for a long, not only in numbers but also in their distribution ranges. In the current study, we collected information on past and current occurrence and distribution records of Asia's megafauna species. We reconstructed the historical distribution ranges of the six herbivores and four carnivores for comparison with their present ranges, to quantify spatially explicit levels of mega-defaunation. Results revealed that historically the selected megafauna species were more widely distributed than at current. Severe range contraction was observed for the Asiatic lion, three rhino species, Asian elephant, tigers, and tapirs. Defaunation maps generated have revealed the vanishing of megafauna from parts of the East, Southeast, and Southwest Asia, even some protected Areas losing up to eight out of ten megafaunal species. These defaunation maps can help develop future conservation policies, to save the remaining distribution ranges of large mammals.

12.
J Nanosci Nanotechnol ; 18(2): 1414-1418, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448602

RESUMO

Magnetic nanoparticles have been intensively developed and applied in several biomedical applications such as targeted delivery, drug therapy, hyperthermia, magnetic resonance imaging and bioseparation etc. This work describes a simple and convenient method to synthesize silica coated Fe3O4 nanoparticles which have the potential to be used in the bioseparation of fetuin from fetal bovine serum and albumin from the egg. In this work, uniform Fe3O4 particles were prepared through the one-pot solvothermal process at 200 °C for 12 h using a sole iron precursor (FeCl3 · 6H2O) and then were coated with SiO2 to prepare silica coated Fe3O4 nanoparticles by hydrolysis and condensation of tetraethyl orthosilicate in ethanol and H2O medium. We further characterized the synthesized Fe3O4 and Fe3O4@SiO2 using XRD, SEM, TEM, FT-IR and VSM to study phase purity, morphology, size, functionality and magnetic properties.

13.
J Pak Med Assoc ; 68(1): 3-9, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29371709

RESUMO

OBJECTIVE: To find out a correlation between the single nucleotide polymorphisms in cluster of differentiation 28 and cluster of differentiation 40 genes with Graves' disease, if any. METHODS: This case-control study was conducted at the Multan Institute of Nuclear Medicine and Radiotherapy, Multan, Pakistan, and comprised blood samples of Graves' disease patients and controls. Various risk factors were also correlated either with the genotype at each single-nucleotide polymorphism or with various combinations of genotypes studied during present investigation. RESULTS: Of the 160 samples, there were 80(50%) each from patients and controls. Risk factor analysis revealed that gender (p=0.008), marital status (p<0.001), education (p<0.001), smoking (p<0.001), tri-iodothyronine (P <0.001), thyroxin (p<0.001) and thyroid-stimulating hormone (p<0.000) levels in blood were associated with Graves' disease. CONCLUSIONS: Both single-nucleotide polymorphisms in both genes were not associated with Graves' disease, either individually or in any combined form.


Assuntos
Antígenos CD28/genética , Antígenos CD40/genética , Doença de Graves/epidemiologia , Doença de Graves/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Predisposição Genética para Doença/genética , Humanos , Pessoa de Meia-Idade , Paquistão/epidemiologia , Fatores de Risco , Adulto Jovem
14.
RSC Adv ; 8(41): 22917-22923, 2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35540125

RESUMO

This paper describes a modified method to prepare monodisperse Fe3O4 magnetic nanoparticles with different shapes (cube, octahedron, and sphere). The shape of the magnetic nanoparticles could be conveniently controlled by changing the types of precursor/capping agent and concentration of capping agent. The prepared samples were characterized using scanning electron microscopy, X-ray diffraction and vibrating sample magnetometry. Cubes and octahedra were formed using ferrous sulfate heptahydrate as an iron source, ethylene glycol as a solvent and potassium hydroxide (KOH) as a capping agent while spheres were formed by using ferric chloride hexahydrate as an iron source, ethylene glycol as a solvent and ammonium acetate as a capping agent. By varying KOH concentration (0.5 M, 1 M, 1.5 M, and 5 M), the shape was transformed from cubes to octahedra because octahedra are developed dominantly at higher concentration of KOH within the reaction mixture. The magnetic studies show superparamagnetic behavior for all samples at room temperature. The Fe3O4 nanoparticles show the magnetic saturation values of 87 emu g-1, 85 emu g-1, and 82 emu g-1 for spheres, cubes, and octahedrons, respectively.

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