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1.
Nature ; 632(8026): 808-814, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39112697

RESUMEN

Earth harbours an extraordinary plant phenotypic diversity1 that is at risk from ongoing global changes2,3. However, it remains unknown how increasing aridity and livestock grazing pressure-two major drivers of global change4-6-shape the trait covariation that underlies plant phenotypic diversity1,7. Here we assessed how covariation among 20 chemical and morphological traits responds to aridity and grazing pressure within global drylands. Our analysis involved 133,769 trait measurements spanning 1,347 observations of 301 perennial plant species surveyed across 326 plots from 6 continents. Crossing an aridity threshold of approximately 0.7 (close to the transition between semi-arid and arid zones) led to an unexpected 88% increase in trait diversity. This threshold appeared in the presence of grazers, and moved toward lower aridity levels with increasing grazing pressure. Moreover, 57% of observed trait diversity occurred only in the most arid and grazed drylands, highlighting the phenotypic uniqueness of these extreme environments. Our work indicates that drylands act as a global reservoir of plant phenotypic diversity and challenge the pervasive view that harsh environmental conditions reduce plant trait diversity8-10. They also highlight that many alternative strategies may enable plants to cope with increases in environmental stress induced by climate change and land-use intensification.


Asunto(s)
Biodiversidad , Clima Desértico , Herbivoria , Ganado , Fenotipo , Plantas , Animales , Cambio Climático , Herbivoria/fisiología , Ganado/fisiología , Plantas/química , Plantas/clasificación , Mapeo Geográfico
2.
Proc Natl Acad Sci U S A ; 121(4): e2309881120, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38190514

RESUMEN

Climate change is increasing the frequency and severity of short-term (~1 y) drought events-the most common duration of drought-globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in the severity and duration of drought studied, and differences among ecosystems in vegetation, edaphic and climatic attributes that can mediate drought impacts. To overcome these problems and better identify the factors that modulate drought responses, we used a coordinated distributed experiment to quantify the impact of short-term drought on grassland and shrubland ecosystems. With a standardized approach, we imposed ~a single year of drought at 100 sites on six continents. Here we show that loss of a foundational ecosystem function-aboveground net primary production (ANPP)-was 60% greater at sites that experienced statistically extreme drought (1-in-100-y event) vs. those sites where drought was nominal (historically more common) in magnitude (35% vs. 21%, respectively). This reduction in a key carbon cycle process with a single year of extreme drought greatly exceeds previously reported losses for grasslands and shrublands. Our global experiment also revealed high variability in drought response but that relative reductions in ANPP were greater in drier ecosystems and those with fewer plant species. Overall, our results demonstrate with unprecedented rigor that the global impacts of projected increases in drought severity have been significantly underestimated and that drier and less diverse sites are likely to be most vulnerable to extreme drought.


Asunto(s)
Sequías , Ecosistema , Pradera , Ciclo del Carbono , Cambio Climático , Proteínas Tirosina Quinasas Receptoras
3.
BMC Plant Biol ; 24(1): 899, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39349996

RESUMEN

BACKGROUND: Red-flesh apples (Malus sieversii f. niedzwetzkyana) have attracted attention from consumers and researchers due to their pleasant appearance and taste. These exotic apples are rich sources of nutrients and health-promoting polyphenols and phenolics. This study aimed to investigate morphological (40 quantitative and 13 qualitative traits) and biochemical (5 traits) characteristics of four socioeconomically important red-fleshed apple populations in North and Northeast region of Iran, which are understudied and under serious extinction risk. RESULTS: The examined characters exhibited wide and statistically significant variations, especially in leaf color (68.86%) and the number of seeds per fruit (61.61%), and more dramatically in the total flavonoids (146.64%) and total phenolics contents (105.81%). There were also strong variations in fresh fruit weight and fruit length, diameter, and flesh thickness. Red, with 34 accessions, was the dominant ripe fruit skin color. All biochemical traits also showed high variations, particularly in total flavonoid content. Red-fleshed Gavramak and Kalateh Khij apples contained the highest biochemical and morphological values, respectively. Principal component analysis (PCA) revealed that the first five principal components together accounted for more than 60.83% variation of the total observed variations. Moreover, the cluster dendrogram analysis based on Ward's method indicated three different clusters based on the characters measured, indicating high variation among the accessions. CONCLUSION: red-flesh apples can be considered suitable sources of natural antioxidants with great potential as healthy foods and nutraceutical applications. Based on the commercial characters, Red-fleshed Gavramak and Kalateh Khij apples showed the highest fruit quality with proper size and thus can be suggested as superior for cultivation or use in breeding programs due to having higher quality fruits.


Asunto(s)
Flavonoides , Frutas , Malus , Malus/anatomía & histología , Irán , Frutas/anatomía & histología , Frutas/química , Flavonoides/análisis , Flavonoides/metabolismo , Fenoles/análisis , Fenoles/metabolismo , Color
4.
Glob Chang Biol ; 28(9): 3110-3144, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34967074

RESUMEN

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.


Asunto(s)
Ecosistema , Suelo , Cambio Climático , Microclima , Temperatura
5.
Drug Dev Ind Pharm ; 48(8): 343-354, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36066848

RESUMEN

Poorly water-soluble drugs like sorafenib tosylate (SFB) can be made more soluble and orally bioavailable using a biocompatible hydrophilic matrix yields amorphous or microcrystalline drugs with high stability and low recrystallization risk. Mesoporous starch (MPS) due to its edibility, biodegradability, high surface area, and confined pores. In this study, MPS, either alone or in combination with polyvinylpyrrolidone (PVP), was employed for improving SFB oral bioavailability. To this aim, MPS was prepared in three steps: gelatinization, solvent exchange, and vacuum drying, after which it was used to incorporate SFB at various ratios using the immersion/solvent evaporation technique. Nitrogen adsorption/desorption analysis, Fourier transform infrared spectrometry (FTIR), field emission scanning electron microscopy (FE-SEM), powder X-ray diffraction (XRD) crystallography, and differential scanning calorimetry (DSC) were used to characterize SFB-loaded and drug-free samples, which confirmed the successful preparation of mesoporous structures with desirable uniform porosity, small pore size (about 5.3 nm), and specific surface area of about 24 m2/g. In-vitro dissolution testing revealed that the SFB dissolution rate increased substantially for the loaded MPS or MPS-PVP samples. Furthermore, when SFB was loaded in MPS-PVP, single-dose pharmacokinetics in rats confirmed an enhanced oral absorption kinetic. Therefore, impregnation of poorly soluble drugs such as SFB in the PVP-modified MPS excipient, which is constructed from a combination of mesoporous materials and a drug recrystallization inhibitor such as hydrophilic polymers, is proposed as a promising strategy for desirable enhancements in drug solubility, oral bioavailability, and efficacy.


Asunto(s)
Portadores de Fármacos , Almidón , Ratas , Animales , Disponibilidad Biológica , Almidón/química , Sorafenib , Portadores de Fármacos/química , Administración Oral , Solventes/química , Povidona
6.
Glob Chang Biol ; 26(1): 119-188, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31891233

RESUMEN

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.


Asunto(s)
Acceso a la Información , Ecosistema , Biodiversidad , Ecología , Plantas
7.
Pharmacol Res ; 159: 104988, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32504833

RESUMEN

OBJECTIVE: The effect of voglibose on metabolic homeostasis is not well characterized. Therefore, we conducted a systematic review and meta-analysis of clinical trials assessing the effect of voglibose on metabolic profile in patients with type 2 diabetes mellitus (T2DM). METHODS: Systematic searches were conducted in PubMed, Scopus, Embase, Google Scholar, Web of Science and Cochrane Library to identify clinical trials assessing the effects of voglibose supplementation on cardio-metabolic profile from incept up to 29 July 2019. Data was pooled using fixed- or random-effect models and weighted mean difference (WMD) as the effect size. RESULTS: Eight clinical trials from 1094 reports, were eligible for inclusion. Pooled findings identified significant reductions in hemoglobin A1c (HbA1c) (WMD= -0.27; 95 %CI -0.49 to -0.05; P = 0.01; I2 = 64.8 %) and an increase in LDL-cholesterol levels (WMD=5.97 mg/dl, 95 % CI 0.88, 11.06, P = 0.02; I2 = 0.0 %). However, no evidence of effect for voglibose intake on T2DM patients was observed for: fasting blood sugar (FBS) (WMD -7.43 mg/dl; 95 %CI -16.56 to 1.71; P = 0.110; I2 = 69.3 %), serum insulin (WMD= -0.15 µU/mL; 95 %CI -0.89 to 0.60; P = 0.70; I2 = 0.0 %), total-cholesterol (WMD=2.82 mg/dl, 95 %CI -2.36 to 8.01, P = 0.70; I2 = 49.7 %), triglycerides (WMD= -7.07 mg/dl, 95 %CI -21.76 to 7.62, P = 0.34; I2 = 0.0 %), HDL-cholesterol levels (WMD= -2.10 mg/dl, 95 %CI -4.48 to 0.27, P = 0.08; I2 = 0.0 %,), body mass index (BMI) (WMD=0.09 kg/m2, 95 %CI -0.70 to 0.87; P = 0.87; I2 = 0.0 %), body weight (WMD= -0.42 kg, 95 %CI -0.84 to 0.00; P = 0.05; I2 = 0.0 %), and adiponectin levels (WMD = 0.32 µg/mL, 95 %CI -0.74 to 1.38; P = 0.55; I2 = 0.0 %). CONCLUSIONS: The current meta-analysis identified a decrease in HbA1c and an increase in LDL-cholesterol with administration of voglibose. However, no significant effect was observed on FBS, insulin, bodyweight, BMI, adiponectin, triglycerides, total- and HDL-cholesterol levels.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Metabolismo Energético/efectos de los fármacos , Inhibidores de Glicósido Hidrolasas/uso terapéutico , Inositol/análogos & derivados , Anciano , Biomarcadores/sangre , LDL-Colesterol/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Femenino , Hemoglobina Glucada/metabolismo , Inhibidores de Glicósido Hidrolasas/efectos adversos , Humanos , Inositol/efectos adversos , Inositol/uso terapéutico , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
8.
Parasitol Res ; 119(12): 4233-4241, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32996050

RESUMEN

Albendazole is known as the drug of choice for medical treatment of cystic echinococcosis (CE). Albendazole sulfoxide (ABZ-SO), as the main active metabolite of albendazole, has low efficacy in the disease due to low water solubility and poor absorptivity. PLGA nanoparticles (NPs) enhance the dissolution of poorly soluble drugs, and chitosan (CS) coating enhances oral drug delivery of NPs. In this study, the efficacy of ABZ-SO-loaded CS-PGLA NPs in the treatment of CE was evaluated in laboratory mice. ABZ-SO-loaded CS-PGLA NPs were prepared by nanoprecipitation and characterized by dynamic light scattering method and scanning electron microscopy. Thirty mice were intraperitoneally infected by 1000 protoscoleces of Echinococcus granulosus. Ten months later, the mice were allocated into 3 groups: groups 1 and 2 were treated with ABZ-SO and ABZ-SO-loaded CS-PGLA NPs, respectively, and the mice in group 3 remained untreated as the control group. The drugs were administered by gavage for 45 days at a daily dose of 10 mg/kg. Finally, all mice were opened and the cysts were collected, counted, weighed, and measured separately. The therapeutic effect of ABZ-SO in the number, weight, and volume of the cysts were not statistically significant compared with those in ABZ-SO-loaded CS-PGLA NPs and the control group. However, the therapeutic effect of ABZ-SO-loaded CS-PGLA NPs in the weight and volume of cysts were statistically significant when compared with that in the control group (p ˂ 0.05). In conclusions, this study revealed that ABZ-SO-loaded CS-PGLA NPs could enhance the therapeutic efficacy of ABZ-SO in the treatment of CE in laboratory mice.


Asunto(s)
Albendazol/análogos & derivados , Antiplatelmínticos/administración & dosificación , Quitosano/química , Equinococosis/tratamiento farmacológico , Ácido Poliglicólico/química , Administración Oral , Albendazol/administración & dosificación , Albendazol/química , Animales , Antiplatelmínticos/química , Quitosano/administración & dosificación , Sistemas de Liberación de Medicamentos , Evaluación Preclínica de Medicamentos , Echinococcus granulosus/efectos de los fármacos , Ratones , Nanopartículas/administración & dosificación , Nanopartículas/química , Ácido Poliglicólico/administración & dosificación
9.
J Ethnobiol Ethnomed ; 20(1): 93, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39367458

RESUMEN

In mountainous areas, wild edible plants are an important part of the local diet. Climate change and anthropogenic activities have profound effects on wild edible plants in these areas. Ethnobotanical studies are important for understanding the use patterns and harvest impacts on these plants. In this regard, the Shahrood region, with its diverse historical/ethnic background, is an appropriate starting point to investigate exploitation patterns and impacts of harvest of wild edible plants. During 2021-2022, ethnobotanical surveys were conducted in 12 villages in the region using semi-structured interviews and participatory observations. Data collection included assessing wild edible plant species diversity, their habitats, collection time and quantities, plant parts used and methods of consumption and preparation. The data were analyzed using use report indicators, relative frequency of citations, and use value (UV). A total of 1086 use reports were documented from a total of 44 interviews. A total of 67 wild species (66 plants and 1 fungus) belonging to 54 genera and 24 families were used as edible in the study area. Rosaceae (9 species), Apiaceae (8), Lamiaceae (8), Asteraceae (7), and Amaryllidaceae (5) were the families with the most reported species. Allium (5 species) was the most diverse genus in terms of species diversity. Herbs were the most commonly used life form (79.1%), followed by shrubs (13.4%) and trees (6%). The most consumed plant parts were young leaves (25%) and young aerial parts (21.4%). There were 13 use categories identified. The majority of edible plants were collected in April-May, mainly from areas nearby villages (37.7%) and rangelands (33.7%). The most important edible plants in the study area were Allium iranicum (Wendelbo) Wendelbo (UV = 1.7), Mentha longifolia (L.) Huds. (1.5), Allium umbilicatum Boiss. (1.47), Tragopogon graminifolius DC. (1.38), Lepidium draba L. (1.27), Urtica dioica L. (1.18), Falcaria vulgaris Bernh. (1.13), Malva neglecta Wallr. (1.11) and Eremurus sp. (1.09). Our results showed diverse and valuable knowledge for wild edible plants in this region, which should be considered in the conservation and management plans in the region.


Asunto(s)
Etnobotánica , Plantas Comestibles , Plantas Comestibles/clasificación , Irán , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Ecosistema
10.
Heliyon ; 10(3): e24949, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38317872

RESUMEN

Several studies have revealed that healthcare nanomaterials are widely used in numerous areas of dentistry, including prevention, diagnosis, treatment, and repair. Nanomaterials in dental cosmetics are utilized to enhance the efficacy of toothpaste and other mouthwashes. Nanoparticles are added to toothpastes for a variety of reasons, including dental decay prevention, remineralization, hypersensitivity reduction, brightening, and antibacterial qualities. In this review, the benefits and uses of many common nanomaterials found in toothpaste are outlined. Additionally, the capacity and clinical applications of nanoparticles as anti-bacterial, whitening, hypersensitivity, and remineralizing agents in the treatment of dental problems and periodontitis are discussed.

11.
Appl Biochem Biotechnol ; 196(8): 5563-5603, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38133881

RESUMEN

Assisted reproductive technologies are key to solving the problems of aging and organ defects. Collagen is compatible with living tissues and has many different chemical properties; it has great potential for use in reproductive medicine and the engineering of reproductive tissues. It is a natural substance that has been used a lot in science and medicine. Collagen is a substance that can be obtained from many different animals. It can be made naturally or created using scientific methods. Using pure collagen has some drawbacks regarding its physical and chemical characteristics. Because of this, when collagen is processed in various ways, it can better meet the specific needs as a material for repairing tissues. In simpler terms, collagen can be used to help regenerate bones, cartilage, and skin. It can also be used in cardiovascular repair and other areas. There are different ways to process collagen, such as cross-linking it, making it more structured, adding minerals to it, or using it as a carrier for other substances. All of these methods help advance the field of tissue engineering. This review summarizes and discusses the current progress of collagen-based materials for reproductive medicine.


Asunto(s)
Colágeno , Medicina Regenerativa , Ingeniería de Tejidos , Ingeniería de Tejidos/métodos , Medicina Regenerativa/métodos , Humanos , Colágeno/química , Animales , Materiales Biocompatibles/química
12.
J Cosmet Dermatol ; 23(6): 2156-2169, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38406887

RESUMEN

BACKGROUND: Acne is a common skin issue that typically occurs during adolescence. It causes long-lasting redness and swelling in the skin. An alternative approach to treating acne could involve using a cosmetic facial mask containing herbal ingredients such as Curcumin and Rosa Damascena extract for its antibacterial properties. AIMS: This study aims to create and try out a peel-off mask gel made from Curcumin and R. Damascena extract. This gel is intended to have the ability to kill bacteria such as Staphylococcus aureus, Escherichia coli, and Propionibacterium acnes and remove dead cells from the skin surface. METHODS: The peel-off mask was made using polyvinyl alcohol (PVA) in 8% and 10% as solidifier. The evaluation of peel-off masks comprises the examination of physiochemical and mechanical aspects. Furthermore, their longevity, effectiveness, and antibacterial properties are also considered. RESULTS: The white color, pleasant smell, and soft texture were the defining features of the peel-off gel mask. The changes in PVA affect the pH level, thickness, and how quickly the peel-off mask dries. The stability test found that the peel-off mask had no significant physical changes when exposed to freezing and thawing. However, there were some differences in color and separation when using the real-time method. A prepared peel-off mask containing 10% PVA and curcumin works best against P. acne. The amount of PVA in the formula affected the physical and chemical qualities, but it did not impact on the antibacterial abilities of the peel-off mask gel. The best formula that gives the best results uses 10% PVA + curcumin. CONCLUSIONS: Using the Curcumin and R. Damascena extract in the creation of the peel-off mask gel ensures its efficacy and safety for skin application.


Asunto(s)
Acné Vulgar , Antibacterianos , Antioxidantes , Curcumina , Extractos Vegetales , Rosa , Staphylococcus aureus , Curcumina/farmacología , Curcumina/administración & dosificación , Extractos Vegetales/farmacología , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Rosa/química , Humanos , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Antioxidantes/farmacología , Antioxidantes/administración & dosificación , Acné Vulgar/tratamiento farmacológico , Acné Vulgar/microbiología , Staphylococcus aureus/efectos de los fármacos , Propionibacterium acnes/efectos de los fármacos , Alcohol Polivinílico/química , Escherichia coli/efectos de los fármacos , Crema para la Piel/administración & dosificación , Piel/efectos de los fármacos , Piel/microbiología , Pruebas de Sensibilidad Microbiana
13.
Artículo en Inglés | MEDLINE | ID: mdl-39110331

RESUMEN

The development of biocompatible wound dressings containing therapeutic agents to accelerate wound healing is an interesting field of study in biomedical sciences. Polyvinyl alcohol (PVA) nanofibers were loaded with zinc oxide nanoparticles (ZnO NPs) and curcumin (Cur) through electrospinning. The dressings were characterized by SEM and XRD and FTIR. The antioxidant, antibacterial, and cytotoxic activities Cur/ZnO/PVA nano dressing were evaluated using DPPH radical scavenging assay, disc diffusion method, and MTT assay, respectively. Cur/ZnO/PVA nano dressing showed sustained Cur release about 19.7% and 61.1% after 8h and 168h, respectively. Cur/ZnO NPs/PVA mixture had higher antioxidant potential than PVA, ZnO NPs, and Cur. The dressing showed a good antibacterial effect. The in vivo wound healing effect of different types of prepared dressings, including PVA, Cur/PVA, Cur/ZnO/PVA, and ZnO/ PVA nanofibers, was also investigated. PVA dressing containing Cur/ZnO NPs resulted in the highest increase of wound contraction in rats. The assembly of Cur and ZnO NPs on PVA nanofibers could propose as an effective delivery method to improve the wound healing process. The investigated wound dressing could be commercialized and used on a large scale after proper further studies, including clinical trials.

14.
BMC Chem ; 18(1): 189, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39342347

RESUMEN

Delivering anticancer drugs to the appropriate site within the body poses a critical challenge in cancer treatment with chemotherapeutic agents like doxorubicin (DOX). Magnetic graphene oxide (GO) nanosheets with generation 1 (G1) amidoamine-dendronized crosslinks were developed by coupling cystamine-functionalized GO nanosheets with Fe3O4 nanoparticles modified with primary amine and methyl acrylate. These magnetic GO nanosheets were loaded with DOX to create a dual pH- and redox-responsive delivery system for cancer chemotherapy. The prepared magnetic nanosheets underwent characterization using FTIR, XRD, DLS, VSM, FE-SEM, and TEM. Physical DOX adsorption was evaluated using various isotherms, including Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich. The in-vitro release profiles of DOX from the magnetic nanosheets were studied under different pH conditions, with and without glutathione (GSH), and the drug release data were fitted with various kinetic models. Additionally, an MTT assay was employed to assess the compatibility and antitumor activity of DOX-loaded magnetic nanosheets in the HepG2 cell line. The results showed that the maximum drug loading was 13.1% (w/w) at a drug/carrier ratio of 1. Without GSH addition, the maximum drug release after 10 days was only 17.9% and 24.1% at pH 7.4 and 5.3, respectively. However, in the presence of GSH, the maximum drug release reached 51.7% and 64.8% at pH 7.4 and 5.3, respectively. Finally, the research findings suggest that the magnetic nanosheets exhibited pH- and redox-stimuli drug release, high biocompatibility, and superior antitumor activity compared to free DOX.

15.
Biomater Adv ; 159: 213797, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38368693

RESUMEN

Theranostics nanoparticles (NPs) have recently received much attention in cancer imaging and treatment. This study aimed to develop a multifunctional nanosystem for the targeted delivery of photothermal and chemotherapy agents. Fe3O4 NPs were modified with polydopamine, bovine serum albumin, and loaded with DOX via a thermal-cleavable Azo linker (Fe3O4@PDA@BSA-DOX). The size of Fe3O4@PDA@BSA NPs was approximately 98 nm under the desired conditions. Because of the ability of Fe3O4 and PDA to convert light into heat, the temperature of Fe3O4@PDA@BSA NPs increased to approximately 47 °C within 10 min when exposed to an 808 nm NIR laser with a power density of 1.5 W/cm2. The heat generated by the NIR laser leads to the breaking of AZO linker and drug release. In vivo and in vitro results demonstrated that prepared NPs under laser irradiation successfully eradicated tumor cells without any significant toxicity effect. Moreover, the Fe3O4@PDA@BSA NPs exhibited the potential to function as a contrasting agent. These NPs could accumulate in tumors with the help of an external magnet, resulting in a significant enhancement in the quality of magnetic resonance imaging (MRI). The prepared novel multifunctional NPs seem to be an efficient system for imaging and combination therapy in melanoma.


Asunto(s)
Compuestos Férricos , Indoles , Melanoma , Polímeros , Humanos , Melanoma/tratamiento farmacológico , Terapia Fototérmica , Medicina de Precisión , Fototerapia/métodos , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Rayos Láser
16.
Nat Plants ; 10(5): 760-770, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38609675

RESUMEN

Perennial plants create productive and biodiverse hotspots, known as fertile islands, beneath their canopies. These hotspots largely determine the structure and functioning of drylands worldwide. Despite their ubiquity, the factors controlling fertile islands under conditions of contrasting grazing by livestock, the most prevalent land use in drylands, remain virtually unknown. Here we evaluated the relative importance of grazing pressure and herbivore type, climate and plant functional traits on 24 soil physical and chemical attributes that represent proxies of key ecosystem services related to decomposition, soil fertility, and soil and water conservation. To do this, we conducted a standardized global survey of 288 plots at 88 sites in 25 countries worldwide. We show that aridity and plant traits are the major factors associated with the magnitude of plant effects on fertile islands in grazed drylands worldwide. Grazing pressure had little influence on the capacity of plants to support fertile islands. Taller and wider shrubs and grasses supported stronger island effects. Stable and functional soils tended to be linked to species-rich sites with taller plants. Together, our findings dispel the notion that grazing pressure or herbivore type are linked to the formation or intensification of fertile islands in drylands. Rather, our study suggests that changes in aridity, and processes that alter island identity and therefore plant traits, will have marked effects on how perennial plants support and maintain the functioning of drylands in a more arid and grazed world.


Asunto(s)
Herbivoria , Suelo , Suelo/química , Plantas , Ecosistema , Clima Desértico , Animales
17.
Drug Deliv Transl Res ; 13(1): 189-221, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36074253

RESUMEN

The global prevalence of cancer is increasing, necessitating new additions to traditional treatments and diagnoses to address shortcomings such as ineffectiveness, complications, and high cost. In this context, nano and microparticulate carriers stand out due to their unique properties such as controlled release, higher bioavailability, and lower toxicity. Despite their popularity, they face several challenges including rapid liver uptake, low chemical stability in blood circulation, immunogenicity concerns, and acute adverse effects. Cell-mediated delivery systems are important topics to research because of their biocompatibility, biodegradability, prolonged delivery, high loading capacity, and targeted drug delivery capabilities. To date, a variety of cells including blood, immune, cancer, and stem cells, sperm, and bacteria have been combined with nanoparticles to develop efficient targeted cancer delivery or diagnosis systems. The review paper aimed to provide an overview of the potential applications of cell-based delivery systems in cancer therapy and diagnosis.


Asunto(s)
Neoplasias , Semen , Masculino , Humanos , Nanotecnología , Neoplasias/diagnóstico , Neoplasias/tratamiento farmacológico
18.
Sci Total Environ ; 830: 154827, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35341847

RESUMEN

Soil biological properties are good indicators for the evaluation of soil quality, introduced as key indicators in soil health, which is in line with the nutrient cycles in terrestrial ecosystems. To the best of the authors' knowledge, responses of belowground biota to habitat degradation have received little attention. The present study aimed to study the effect of different intensities of vegetation degradation [heavy (0-10% coverage), moderate (30-40% coverage) and light (60-70% coverage)] and non-degraded sites (as control; 90-100% coverage) in lands covered by Crataegus and Berberis shrubs on soil fauna, microbiota and microbial activities in the north of Iran. From each of these sites, 45 soil (30 × 30 cm area) samples were taken from 0 to 10 cm, 10-20 cm and 20-30 cm depths and 180 samples were transferred to the laboratory. According to principal component analysis, the studied habitats can be distinguished based on soil health and functional characteristics. In this regard, due to the more fertile soil in ecosystems without degradation, highest soil biological activities belonged to these areas. Following the increase in the intensity of degradation, the population of soil organisms and microbial activities are suppressed due to reduction of organic matter inputs, unsuitable soil microclimate, increase in soil erosion and finally depletion of soil nutrients. The results of this study indicate the dependence of soil quality on aboveground vegetation cover, especially in the topsoil, so the vegetation degradation can cause severe damages to soil health in semi-arid regions.


Asunto(s)
Ecosistema , Suelo , Biota , Clima Desértico , Microbiología del Suelo
19.
Sci Total Environ ; 853: 158664, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36096213

RESUMEN

Vegetation degradation can have significant effects on organic matter fractions as well as various soil characteristics. All these can lead to the changes in soil microbial communities, which are main drivers of nutrient cycles. This is especially important for mountainous ecosystems that are very sensitive and fragile habitats due to their climatic conditions, but less attention has been paid to them. Thus, Mirkola mountainous region (northern Iran) with semi-arid climate and vegetation being dominated by Crataegus and Berberis shrubs were investigated in this study. Sites with different intensities of vegetation degradation [light (60-70 % coverage), moderate (30-40 % coverage) and heavy (0-10 % coverage)] and also non-degraded control sites (90-100 % coverage) were selected. In order to avoid pseudoreplication, three plots, each with an area of 1 ha (100 m × 100 m), were used for each of the four studied habitats. Soil (in three soil depths at 0-10 cm, 10-20 cm and 20-30 cm) samples were collected from the corners and also the center (n = 5) of the plots using iron frames (30 × 30 cm). A total of 180 soil samples (4 habitats × 15 sample × 3 depths) were transferred to the laboratory. Labile and non-labile contents of soil organic matter (SOM) (C and N in soil particles and aggregates, C and N stocks, particulate and dissolved organic matter, hot-water extractable carbohydrate, C and N mineralization) were measured in each of these sites. Results showed that vegetation degradation might result in both labile and non-labile SOM losses. SOM and its associated properties were highest in the non-degraded sites, whereas, lower values were common under degraded areas. Based on the obtained data, vegetation cover can enhance the amount of organic matter entering the soil (especially in the surface layers) and formation of fertile islands in ecosystems. Accordingly, vegetation protection is emphasized to maintain stability and provide ecosystem services in mountainous semi-arid regions.


Asunto(s)
Microbiota , Suelo , Ecosistema , Agua , Hierro , Carbohidratos , Carbono
20.
Ecol Evol ; 12(1): e8552, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35127050

RESUMEN

Although the diversity-disturbance relationship has been extensively studied, the differences in responses of taxonomic vs. functional diversity to natural disturbances (i.e., fire) call for an improved understanding of this relationship. Here, we investigated how fire disturbance influenced plant taxonomic and functional diversity in Golestan National Park, in northeastern Iran. We evaluated the response of α- and ß-plant diversity considering both taxonomic and functional diversity and different ß-diversity components (i.e., turnover and nestedness) as a function of fire regime, topographic exposure, and their interactive effect. We considered different indices of functional diversity including functional richness, functional evenness, functional divergence, functional dispersion, Rao's quadratic entropy, and community-weighted mean (CWM). Functional diversity indices were computed using four leaf traits related to species growth strategy and fire response including leaf thickness and leaf length, specific leaf area (SLA) and leaf dry matter content (LDMC). Taxonomic and functional diversity had contrasting response to fire disturbance. Fire significantly decreased taxonomic α-diversity similarly in both north and south exposures. ß-diversity increased in south exposures but decreased in north exposures. Fire decreased functional richness, increased CWM of SLA, and decreased CWM of LDMC. In contrast, abundance-weighted metrics of functional diversity (functional evenness, functional divergence, functional dispersion, Rao's quadratic entropy) were not impacted by fire disturbance. Finally, the main contributors to heterogeneity were driven by a fire × exposure interaction, suggesting that fire disturbance interacts with topographic exposure. Our results suggest that taxonomic and functional α- and ß-diversity have contrasting responses to fire illustrating the need to consider both dimensions to understand how disturbance impacts plant communities. At large spatial scale, species turnover and nestedness appear as essential parameters to maintain species-rich communities in response to fire disturbance.

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