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1.
J Environ Manage ; 368: 122198, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39168010

RESUMEN

Nitrogen (N) deposition is a significant threat to the functioning of forests and negatively impacts the delivery of forest goods and services. Contemporary management approaches seek to adapt forests to such N-deposition stressors, but to date how plant populations in natural forests respond to N deposition and what factors determine the contrasting responses among populations are still unclear. Here, we investigated the impact of N-addition (control: 0 kg ha-1 yr-1; low: 25 kg ha-1 yr-1; medium: 50 kg ha-1 yr-1; high: 75 kg ha-1 ha yr-1) on tree population temporal stability and how initial tree size, mycorrhizal type, and leaf N content (LNC; as a surrogate for functional trait composition) mediate tree population responses to N-addition in a Korean pine and mixed broadleaved dominated temperate forest in northern China. We quantified tree species population temporal stability as the ratio of mean to standard deviation of the year-by-year stem increments recorded in individual trees from 2015 to 2022 experimental period. The results showed different temporal stabilities of tree species among four N-addition levels, with the highest population stability observed within the high N-addition plots. Furthermore, initial tree size had significantly (p < 0.001) positive effects on population temporal stability. The effect of LNC and initial tree size were also contingent on the level of N applied. Specifically, increase in tree population LNC reduced population temporal stability in all plots where N was added. Our results imply that retention of large-sized trees and species with resource-conservative strategies (e.g., low LNC) could enhance forest stability under N deposition.


Asunto(s)
Bosques , Nitrógeno , Árboles , Nitrógeno/análisis , China , Hojas de la Planta
2.
Plant Cell Environ ; 46(3): 669-687, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36581782

RESUMEN

Trichomes are epidermal outgrowths on plant shoots. Their roles in protecting plants against herbivores and in the biosynthesis of specialized metabolites have long been recognized. Recently, studies are increasingly showing that trichomes also play important roles in water absorption and metal detoxication, with these roles having important implications for ecology, the environment, and agriculture. However, these two functions of trichomes have been largely overlooked and much remains unknown. In this review, we show that the trichomes of 37 plant species belonging to 14 plant families are involved in water absorption, while the trichomes of 33 species from 13 families are capable of sequestering metals within their trichomes. The ability of trichomes to absorb water results from their decreased hydrophobicity compared to the remainder of the leaf surface as well as the presence of special structures for collecting and absorbing water. In contrast, the metal detoxication function of trichomes results not only from the good connection of their basal cells to the underlying vascular tissues, but also from the presence of metal-chelating ligands and transporters within the trichomes themselves. Knowledge gaps and critical future research questions regarding these two trichome functions are highlighted. This review improves our understanding on trichomes.


Asunto(s)
Tricomas , Agua , Agua/metabolismo , Tricomas/metabolismo , Metales/metabolismo , Hojas de la Planta/metabolismo , Plantas
3.
Environ Toxicol ; 38(8): 1989-2001, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37163306

RESUMEN

Lung cancer is among the most aggressive types of malignant tumors that contributes to cancer-associated deaths worldwide with a high occurrence and fatality rate. Histone deacetylase 2 (HDAC2), prevent the aberrant transcription of a number of genes that are primarily responsible for controlling the cell cycle, cell proliferation, and signaling pathways in numerous cancers. Previous studies reported the role of HDACs and YY1 in the growth and development of several cancers. Although, it is noteworthy that remarkable efforts have been taken for the treatment of lung cancer using molecularly targeted therapies and chemotherapeutic agents, but the outcome is still poor for this critically persistent cancer. Therefore, the aim of the present study is to identify an efficacious, novel therapeutic biomarkers for the successful diagnosis of lung cancer at the early stage of the disease and the molecular insights involved. In the present study, qPCR and western bot data revealed that the expression level of HDAC2 and YY1 were upregulated in the cell lines and tumor samples of lung cancer patients. Moreover, MTT, qPCR, western blot, cell cycle analysis, and migration assays showed that inhibition of HDAC2 reduced YY1 expression, similarly, depletion of YY1 using knockdown approach inhibited the proliferation, migration, invasion, and blockage of the cell cycle by suppressing c-Myc in lung cancer cell lines. In conclusion, the current study findings support the notion that HDAC2's anticancer role was attributed through YY1 regulation by targeting c-Myc and could act as potential novel candidate biomarker for the lung cancer diagnosis.


Asunto(s)
Neoplasias Pulmonares , MicroARNs , Humanos , MicroARNs/genética , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Línea Celular Tumoral , Histona Desacetilasa 2/genética , Histona Desacetilasa 2/metabolismo , Transducción de Señal , Neoplasias Pulmonares/patología , Proliferación Celular/genética , Movimiento Celular/genética , Regulación Neoplásica de la Expresión Génica , Factor de Transcripción YY1/genética , Factor de Transcripción YY1/metabolismo
4.
J Pak Med Assoc ; 73(2): 253-257, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36800705

RESUMEN

OBJECTIVE: To determine the correlation of muscle length and muscle strength with balance and functional status among children with diplegic spastic cerebral palsy. METHODS: The cross-sectional study was conducted from February to July 2021 at the Physical Therapy Department of Chal Foundation and Fatima Physiotherapy Centre, Swabi, Pakistan, and comprised children aged 4-12 years with diplegic spastic cerebral palsy. The strength of back and lower limb muscles was assessed through manual muscles testing. Lower limb muscle's length, indicating tightness, was assessed using goniometer. Paediatric balance scale and gross motor function measure scale-88 were used to assess balance and gross motor function. Data was analysed using SPSS 23. RESULTS: Of the 83 subjects, 47(56.6%) were boys and 36(43.4%) were girls. The overall mean age was 7.31±2.02 years, mean weight was 19.71±5.45kg, mean height was 105.5±14cm and mean body mass index was 17.32±1.64 kg/m2. There was a positive and significant correlation of all the lower limb muscles' strength with balance (p<0.01) and functional status (p<0.01). The correlation between the tightness of muscles and balance was significant and negative for all lower limb muscles (p<0.005). The correlation between the muscles' tightness and functional status was negative and significant for all lower limb muscles (p<0.005). CONCLUSIONS: Good muscle strength and appropriate flexibility of lower limb muscles enhanced functional status and good balance in children with diplegic spastic cerebral palsy.


Asunto(s)
Parálisis Cerebral , Masculino , Femenino , Niño , Humanos , Preescolar , Estudios Transversales , Estado Funcional , Músculos , Extremidad Inferior
5.
Glob Chang Biol ; 28(17): 5254-5268, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35703577

RESUMEN

Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research-from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring programmes. However, these data can be surprisingly hard to come by, particularly for certain regions of the world and for specific taxonomic groups, posing a real barrier to progress in these fields. To overcome this challenge, we developed the Tallo database, a collection of 498,838 georeferenced and taxonomically standardized records of individual trees for which stem diameter, height and/or crown radius have been measured. These data were collected at 61,856 globally distributed sites, spanning all major forested and non-forested biomes. The majority of trees in the database are identified to species (88%), and collectively Tallo includes data for 5163 species distributed across 1453 genera and 187 plant families. The database is publicly archived under a CC-BY 4.0 licence and can be access from: https://doi.org/10.5281/zenodo.6637599. To demonstrate its value, here we present three case studies that highlight how the Tallo database can be used to address a range of theoretical and applied questions in ecology-from testing the predictions of metabolic scaling theory, to exploring the limits of tree allometric plasticity along environmental gradients and modelling global variation in maximum attainable tree height. In doing so, we provide a key resource for field ecologists, remote sensing researchers and the modelling community working together to better understand the role that trees play in regulating the terrestrial carbon cycle.


Asunto(s)
Bosques , Árboles , Biomasa , Carbono/metabolismo , Ciclo del Carbono , Ecosistema , Árboles/fisiología
6.
J Theor Biol ; 532: 110914, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34582825

RESUMEN

p53 protein plays an essential role in protecting the genomic integrity of mammalian cells. A drastic decrease in the amount of p53 protein has been observed in cancerous cells. By using Nutlin-based small molecule drugs, the concentration of p53 can be restored to the desired level. This paper presents the drug-dosage design for p53 pathway, based on a control-oriented nonlinear model. A chattering free sliding mode control (CFSMC) strategy is employed to track the desired trajectory of p53 concentration for both of its dynamic behaviors, i.e., sustained and oscillatory responses. A gain-scheduled modified Utkin observer (GSMUO) is designed for robust state reconstruction and disturbance estimation. The simulation results show that CFSMC and GSMUO exhibit desired robustness and performance properties in the presence of parametric variations, an input disturbance and measurement noise. Moreover, a comprehensive simulation study, along with a detailed quantitative analysis is performed to compare CFSMC-GSMUO with four different techniques: a sliding mode control (SMC) with an equivalent control based sliding mode observer (SMO) and GSMUO, respectively, and a dynamic sliding mode control (DSMC) with SMO and GSMUO, respectively. The analysis demonstrates that the tracking error and utilization of the control energy is the least in the case of CFSMC-GSMUO as compared to its counterparts.


Asunto(s)
Algoritmos , Proteína p53 Supresora de Tumor , Simulación por Computador , Dinámicas no Lineales
7.
J Head Trauma Rehabil ; 37(4): E249-E257, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34354018

RESUMEN

OBJECTIVE: To provide a systematic review of published interventions for posttraumatic brain injury fatigue (PTBIF). METHODS: PubMed and OneSearch were systematically searched for PTBIF interventions published between January 1, 1989, and March 31, 2019. Search results were evaluated for inclusion based on an abstract and full-text review. Inclusion criteria were (1) an investigation of an intervention, (2) participant sample including individuals with traumatic brain injury (TBI), (3) report of fatigue outcome data among individuals with TBI, and (4) articles available in English, Spanish, French, German, Afrikaans, or Dutch. A risk of bias assessment was conducted on all included publications. RESULTS: The search resulted in 2343 publications, with 37 meeting inclusion criteria for this review. Categories of PTBIF interventions were pharmacological ( n = 13), psychological ( n = 9), exercise-based ( n = 4), complementary alternative medicine ( n = 5), electrotherapeutic ( n = 3), and multimodal ( n = 3). Only methylphenidate, modafinil, and cognitive behavioral therapy interventions included multiple cohorts. Pharmacological and psychological interventions represented the groups with the lowest risk of bias. CONCLUSIONS: This review includes 37 studies, with 21 studies published after 2014. Methylphenidate and melatonin were the only pharmacological agents found to reduce fatigue in randomized controlled trials. Creatine given to children prospectively at onset of injury reduced fatigue at follow-up. Walking and water aerobics were effective exercise interventions in isolated randomized controlled studies. One multimodal study of children after concussion was more effective at reducing fatigue and postconcussion symptoms than community standard of care. Other interventions had equivocal results. Overall, more work remains to understand and develop treatments for PTBIF.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Fatiga , Conmoción Encefálica/complicaciones , Conmoción Encefálica/terapia , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/terapia , Creatina/uso terapéutico , Fatiga/etiología , Fatiga/terapia , Humanos , Melatonina/uso terapéutico , Metilfenidato/uso terapéutico
8.
J Environ Manage ; 303: 114140, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34836676

RESUMEN

Species diversity plays an essential role in enhancing ecosystem functions (EF) in both natural and plantation forests. However, we do not fully understand whether species diversity could maintain the sustainability of EFs in multiple-rotation plantations. Here, we hypothesized that tree species mixtures could mitigate declines in EFs along successive rotations, but could not maintain ecosystem multifunctionality. To test our hypothesis, we examined the effects of species diversity on four EFs, i.e., aboveground biomass (AGB), soil available nitrogen (SAN) and phosphorus (SAP), and soil organic matter (SOM), based on pure model simulation in plantations of subtropical China. The model fusion framework was set up by the integration of the process-based FORECAST and Multivariate Diversity-Interactions models. In the simulation, four local typical plantation tree species (two conifers, one evergreen broadleaf, and one deciduous N-fixing broadleaf) were selected and combined to form four monoculture and 11 mixture stands, and for each stand, the simulation was made for four 25-year rotations. The results showed that all the four EFs declined with the progress of rotations in both monoculture and mixtures, and the declining range was larger in monoculture than in mixtures in each rotation. Particularly, SAP significantly decreased while AGB, SAN, and SOM increased with diversity evenness from 0 (monoculture) to 1 (four species being equal abundant in the mixture). Overall, SAP and AGB displayed higher sensitivity to the disturbance of successive rotations compared with SAN and SOM. These results suggest that mixing species could not maintain EFs along with successive rotations because it could not alleviate SAP deficiencies in the soils resulted from the disturbances of silvicultural measures.


Asunto(s)
Ecosistema , Bosques , Biodiversidad , Biomasa , China , Nutrientes , Suelo , Árboles
9.
J Environ Manage ; 315: 115177, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35500492

RESUMEN

In tropical forests, several studies have explored the effects of environmental factors and tree species diversity as well as functional trait diversity and trait composition on aboveground biomass (AGB) stock. However, these abiotic and biotic effects on individual biomass variability (BioVar) are still largely unexplored, which limits our understanding of the plant-plant interactions for species coexistence. Here, we used the Partial Least Squares Structural Equation Models (PLS-SEMs), and other complementary analyses, on data from 189 tropical forest plots in Sri Lanka, to test the linkages amongst climate (a latent variable of solar radiation and potential evapotranspiration), soil (pH and cation exchange capacity), plot (plot size and stand density) conditions, big-sized trees, species-functional diversity, and BioVar. The PLS-SEMs showed that climate conditions decreased BioVar directly but increased indirectly via integrative promoting direct effects on soil conditions, species-functional diversity and big-sized trees. In contrast, soil conditions increased BioVar directly but decreased indirectly via integrative suppressing direct effects on species-functional diversity and big-sized trees. Interestingly, we found that the divergent indirect effects of climate and soil conditions on BioVar via big-sized trees mattered when the direct effect of big-sized trees on species-functional diversity was considered as compared to the reverse effect in PLS-SEMs. Also, the indirect positive effect of plot properties on BioVar was nearly equal to the direct effect because plot properties affected big-sized trees as similar as or lower than species-functional diversity. The positive effect of species-functional diversity on BioVar was mediated by the structural attributes of big-sized trees, indicating increased plant species co-existence. This study suggests that individual tree biomass variability (i.e., BioVar) should be considered for managing natural tropical forests in the context of the plant-plant interactions for species coexistence.


Asunto(s)
Biodiversidad , Clima , Biomasa , Suelo , Sri Lanka , Clima Tropical
10.
Glob Chang Biol ; 27(12): 2883-2894, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33742479

RESUMEN

Biodiversity plays a fundamental role in provisioning and regulating forest ecosystem functions and services. Above-ground (plants) and below-ground (soil microbes) biodiversity could have asynchronous change paces to human-driven land-use impacts. Yet, we know very little how they affect the provision of multiple forest functions related to carbon accumulation, water retention capacity and nutrient cycling simultaneously (i.e. ecosystem multifunctionality; EMF). We used a dataset of 22,000 temperate forest trees from 260 plots within 11 permanent forest sites in Northeastern China, which are recovering from three post-logging disturbances. We assessed the direct and mediating effects of multiple attributes of plant biodiversity (taxonomic, phylogenetic, functional and stand structure) and soil biodiversity (bacteria and fungi) on EMF under the three disturbance levels. We found the highest EMF in highly disturbed rather than undisturbed mature forests. Plant taxonomic, phylogenetic, functional and stand structural diversity had both positive and negative effects on EMF, depending on how the EMF index was quantified, whereas soil microbial diversity exhibited a consistent positive impact. Biodiversity indices explained on average 45% (26%-58%) of the variation in EMF, whereas climate and disturbance together explained on average 7% (0.4%-15%). Our result highlighted that the tremendous effect of biodiversity on EMF, largely overpassing those of both climate and disturbance. While above- (ß = 0.02-0.19) and below-ground (ß = 0.16-0.26) biodiversity had direct positive effects on EMF, their opposite mediating effects (ß = -0.22 vs. ß = 0.35 respectively) played as divergent pathways to human disturbance impacts on EMF. Our study sheds light on the need for integrative frameworks simultaneously considering above- and below-ground attributes to grasp the global picture of biodiversity effects on ecosystem functioning and services. Suitable management interventions could maintain both plant and soil microbial biodiversity, and thus guarantee a long-term functioning and provisioning of ecosystem services in an increasing disturbance frequency world.


Asunto(s)
Biodiversidad , Ecosistema , China , Bosques , Humanos , Filogenia
11.
Sensors (Basel) ; 21(11)2021 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-34070719

RESUMEN

Recently, the concept of combining 'things' on the Internet to provide various services has gained tremendous momentum. Such a concept has also impacted the automotive industry, giving rise to the Internet of Vehicles (IoV). IoV enables Internet connectivity and communication between smart vehicles and other devices on the network. Shifting the computing towards the edge of the network reduces communication delays and provides various services instantly. However, both distributed (i.e., edge computing) and central computing (i.e., cloud computing) architectures suffer from several inherent issues, such as high latency, high infrastructure cost, and performance degradation. We propose a novel concept of computation, which we call moisture computing (MC) to be deployed slightly away from the edge of the network but below the cloud infrastructure. The MC-based IoV architecture can be used to assist smart vehicles in collaborating to solve traffic monitoring, road safety, and management issues. Moreover, the MC can be used to dispatch emergency and roadside assistance in case of incidents and accidents. In contrast to the cloud which covers a broader area, the MC provides smart vehicles with critical information with fewer delays. We argue that the MC can help reduce infrastructure costs efficiently since it requires a medium-scale data center with moderate resources to cover a wider area compared to small-scale data centers in edge computing and large-scale data centers in cloud computing. We performed mathematical analyses to demonstrate that the MC reduces network delays and enhances the response time in contrast to the edge and cloud infrastructure. Moreover, we present a simulation-based implementation to evaluate the computational performance of the MC. Our simulation results show that the total processing time (computation delay and communication delay) is optimized, and delays are minimized in the MC as apposed to the traditional approaches.

12.
Pak J Pharm Sci ; 34(3): 995-1001, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34602424

RESUMEN

A novel method, for the synthesis of silver nanoparticles that are eco-friendly by means of mixed reductants method, has been developed. The combined extract of Mentha viridis plant and Prunus domestica gum were used as reducing agents for the synthesis of silver nanoparticles of the size less than 40 nm in diameter. The effect of time and concentration on the formation of silver nanoparticles were also monitored. The silver nanoparticles formed were verified by surface Plasmon spectra using single and double beam UV-Vis spectrophotometer. The XRD technique and scanning electron microscopy were performed to analyze the crystalline structure, crystallite size and morphology. The synthesized silver nanoparticles were tested against different bacterial and fungus strains. The silver nanoparticles showed good inhibition in antimicrobial study and low MIC for bacterial strains. The antioxidant assay was performed to check the scavenging activity. In DPPH, the silver nanoparticles showed good scavenging activity and were found close to that of ascorbic acid.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Mentha , Nanopartículas del Metal , Prunus domestica , Plata/farmacología , Antiinfecciosos/química , Antioxidantes/química , Aspergillus/efectos de los fármacos , Candida albicans/efectos de los fármacos , Técnicas de Química Sintética , Química Farmacéutica , Fusarium/efectos de los fármacos , Hypocreales/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Microscopía Electrónica de Rastreo , Penicillium chrysogenum/efectos de los fármacos , Espectroscopía de Fotoelectrones , Extractos Vegetales , Gomas de Plantas , Proteus vulgaris/efectos de los fármacos , Pseudomonas/efectos de los fármacos , Sustancias Reductoras , Plata/química , Nitrato de Plata , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Resonancia por Plasmón de Superficie
13.
Semin Cell Dev Biol ; 69: 34-39, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28627382

RESUMEN

Spectraplakins are multifunctional cytoskeletal linker proteins that act as important communicators, connecting cytoskeletal components with each other and to cellular junctions. Bullous pemphigoid antigen 1 (BPAG1)/dystonin is a member of spectraplakin family and expressed in various tissues. Alternative splicing of BPAG1 gene produces various isoforms with unique structure and domains. BPAG1 plays crucial roles in numerous biological processes, such as cytoskeleton organization, cell polarization, cell adhesion, and cell migration as well as signaling transduction. Genetic mutation of BPAG1 isoforms is the miscreant of epidermolysis bullosa and multifarious, destructive neurological diseases. In this review, we summarize the recent advances of BPAG1's role in various biological processes and in skin and neurological diseases.


Asunto(s)
Distonina/metabolismo , Enfermedades del Sistema Nervioso/metabolismo , Enfermedades de la Piel/metabolismo , Animales , Distonina/química , Distonina/genética , Humanos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Distribución Tisular
14.
Glob Chang Biol ; 25(8): 2810-2824, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31120573

RESUMEN

Large-diameter, tall-stature, and big-crown trees are the main stand structures of forests, generally contributing a large fraction of aboveground biomass, and hence play an important role in climate change mitigation strategies. Here, we hypothesized that the effects of large-diameter, tall-stature, and big-crown trees overrule the effects of species richness and remaining trees attributes on aboveground biomass in tropical forests (i.e., we term the "big-sized trees hypothesis"). Specifically, we assessed the importance of: (a) the "top 1% big-sized trees effect" relative to species richness; (b) the "99% remaining trees effect" relative to species richness; and (c) the "top 1% big-sized trees effect" relative to the "99% remaining trees effect" and species richness on aboveground biomass. Using environmental factor and forest inventory datasets from 712 tropical forest plots in Hainan Island of southern China, we tested several structural equation models for disentangling the relative effects of big-sized trees, remaining trees attributes, and species richness on aboveground biomass, while considering for the full (indirect effects only) and partial (direct and indirect effects) mediation effects of climatic and soil conditions, as well as interactions between species richness and trees attributes. We found that top 1% big-sized trees attributes strongly increased aboveground biomass (i.e., explained 55%-70% of the accounted variation) compared to species richness (2%-18%) and 99% remaining trees attributes (6%-10%). In addition, species richness increased aboveground biomass indirectly via increasing big-sized trees but via decreasing remaining trees. Hence, we show that the "big-sized trees effect" overrides the effects of remaining trees attributes and species richness on aboveground biomass in tropical forests. This study also indicates that big-sized trees may be more susceptible to atmospheric drought. We argue that the effects of big-sized trees on species richness and aboveground biomass should be tested for better understanding of the ecological mechanisms underlying forest functioning.


Asunto(s)
Biodiversidad , Árboles , Biomasa , China , Cambio Climático , Clima Tropical
15.
Ecol Indic ; 1072019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31478008

RESUMEN

Understanding the effects of plant species diversity and trait composition on aboveground biomass is a central focus of ecology and has important implications for biodiversity conservation. However, the simultaneous direct and indirect effects of soil nutrients, species asynchrony, functional trait diversity, and trait composition for explaining the community temporal stability of aboveground biomass remain underrepresented in natural forests. Here, we hypothesized that species asynchrony relative to soil nutrients, functional trait diversity, and trait composition plays a central role in stabilizing the community temporal stability of natural forests. We tested this hypothesis using a structural equation model based on 10-year continuous monitoring data (i.e., three-time repeated forest inventories) in both second-growth and old-growth temperate forests in northeast China. Our results showed that the community temporal stability of aboveground biomass was driven by a strong direct positive effect of species asynchrony in both second-growth and old-growth temperate forests, whereas functional trait diversity and composition (i.e. community-weighted mean of leaf nitrogen content) were of additional importance in an old-growth forest only. Functional trait diversity decreased community-weighted mean of leaf nitrogen content in an old-growth forest, whereas this relationship was non-significant in a second-growth forest. Soil nutrients had non-significant effects on the community temporal stability of both second-growth and old-growth forests. Species asynchrony was the direct determinant of the community temporal stability of aboveground biomass in temperate forests. The direct effect of species asynchrony increased with forest succession, implying that temporal niche differentiation and facilitation increase over time. This study suggests that managing forests with mixtures of both early and late successional species or shade intolerant and tolerant species, not only species diversity, is important for maintaining forest stability in a changing environment. We argue that the species asynchrony effect is crucial to understand the underlying ecological mechanisms for a diversity-biomass relationship in natural forests.

16.
Trop Anim Health Prod ; 51(7): 1927-1933, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30972624

RESUMEN

The present study aimed at investigating the percent prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in equines and associated personnel. A total of 150 swabs of equines and 50 nasal swab samples of associated personnel were collected. These samples were processed in mannitol salt broth for enrichment. A total of 175 nasal swab samples changed the broth color from pink to yellow which were detected as samples containing S. aureus. These samples were processed further on specific media, namely mannitol salt agar, Staph-110, and blood agar, for phenotypic and Gram's staining-based confirmation of S. aureus isolates. Out of these 175 S. aureus-positive samples, 150 were of equine and 25 were of human origin. Identification of MRSA isolates in 175 S. aureus-positive samples was carried out by antimicrobial susceptibility testing by disc diffusion method. Results showed the presence of MRSA in 87 samples, out of which 81 samples were collected from equines and six samples from humans. Results of antibiotic testing revealed that percentage positivity of MRSA was higher (54%) in equines as compared with the associated personnel (24%). Most resistant antibiotics against MRSA isolates were oxacillin and methicillin while linezolid was found to be the most sensitive antibiotic against MRSA. In conclusion, our findings indicated prevalence of MRSA in equines and associated personnel evidencing an occupational risk of contracting MRSA from horses.


Asunto(s)
Antibacterianos/farmacología , Caballos/microbiología , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Agar , Animales , Estudios Transversales , Medios de Cultivo , Humanos , Meticilina , Resistencia a la Meticilina , Pruebas de Sensibilidad Microbiana , Prevalencia , Zoonosis
17.
Int J Mol Sci ; 19(4)2018 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-29587367

RESUMEN

Cancer is a highly lethal disease that is characterized by aberrant cell proliferation, migration, and adhesion, which are closely related to the dynamic changes of cytoskeletons and cytoskeletal-adhesion. These will further result in cell invasion and metastasis. Plakins are a family of giant cytolinkers that connect cytoskeletal elements with each other and to junctional complexes. With various isoforms composed of different domain structures, mammalian plakins are broadly expressed in numerous tissues. They play critical roles in many cellular processes, including cell proliferation, migration, adhesion, and signaling transduction. As these cellular processes are key steps in cancer development, mammalian plakins have in recent years attracted more and more attention for their potential roles in cancer. Current evidence shows the importance of mammalian plakins in various human cancers and demonstrates mammalian plakins as potential biomarkers for cancer. Here, we introduce the basic characteristics of mammalian plakins, review the recent advances in understanding their biological functions, and highlight their roles in human cancers, based on studies performed by us and others. This will provide researchers with a comprehensive understanding of mammalian plakins, new insights into the development of cancer, and novel targets for cancer diagnosis and therapy.


Asunto(s)
Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias/metabolismo , Plaquinas/genética , Plaquinas/metabolismo , Animales , Movimiento Celular , Proliferación Celular , Citoesqueleto/metabolismo , Humanos , Ratones , Ratones Noqueados , Invasividad Neoplásica , Metástasis de la Neoplasia , Neoplasias/patología , Transducción de Señal
18.
Int J Mol Sci ; 19(2)2018 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-29370110

RESUMEN

Osteoporosis is a progressive skeletal disease characterized by decreased bone mass and degraded bone microstructure, which leads to increased bone fragility and risks of bone fracture. Osteoporosis is generally age related and has become a major disease of the world. Uncovering the molecular mechanisms underlying osteoporosis and developing effective prevention and therapy methods has great significance for human health. Mesenchymal stem cells (MSCs) are multipotent cells capable of differentiating into osteoblasts, adipocytes, or chondrocytes, and have become the favorite source of cell-based therapy. Evidence shows that during osteoporosis, a shift of the cell differentiation of MSCs to adipocytes rather than osteoblasts partly contributes to osteoporosis. Thus, uncovering the molecular mechanisms of the osteoblast or adipocyte differentiation of MSCs will provide more understanding of MSCs and perhaps new methods of osteoporosis treatment. The MSCs have been applied to both preclinical and clinical studies in osteoporosis treatment. Here, we review the recent advances in understanding the molecular mechanisms regulating osteoblast differentiation and adipocyte differentiation of MSCs and highlight the therapeutic application studies of MSCs in osteoporosis treatment. This will provide researchers with new insights into the development and treatment of osteoporosis.


Asunto(s)
Adipocitos/citología , Diferenciación Celular , Células Madre Mesenquimatosas/citología , Osteoblastos/citología , Osteoporosis/terapia , Adipocitos/metabolismo , Animales , Humanos , Trasplante de Células Madre Mesenquimatosas/efectos adversos , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/metabolismo , Osteoporosis/etiología
19.
J Environ Manage ; 205: 308-318, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29031134

RESUMEN

The positive relationships between biodiversity and aboveground biomass are important for biodiversity conservation and greater ecosystem functioning and services that humans depend on. However, the interaction effects of plant coverage and biodiversity on aboveground biomass across plant growth forms (shrubs, forbs and grasses) in natural rangelands are poorly studied. Here, we hypothesized that, while accounting for environmental factors and disturbance intensities, the positive relationships between plant coverage, biodiversity, and aboveground biomass are ubiquitous across plant growth forms in natural rangelands. We applied structural equation models (SEMs) using data from 735 quadrats across 35 study sites in semi-steppe rangelands in Iran. The combination of plant coverage and species richness rather than Shannon's diversity or species diversity (a latent variable of species richness and evenness) substantially enhance aboveground biomass across plant growth forms. In all selected SEMs, plant coverage had a strong positive direct effect on aboveground biomass (ß = 0.72 for shrubs, 0.84 for forbs and 0.80 for grasses), followed by a positive effect of species richness (ß = 0.26 for shrubs, 0.05 for forbs and 0.09 for grasses), and topographic factors. Disturbance intensity had a negative effect on plant coverage, whereas it had a variable effect on species richness across plant growth forms. Plant coverage had a strong positive total effect on aboveground biomass (ß = 0.84 for shrubs, 0.88 for forbs, and 0.85 for grasses), followed by a positive effect of species richness, and a negative effect of disturbance intensity across plant growth forms. Our results shed light on the management of rangelands that is high plant coverage can significantly improve species richness and aboveground biomass across plant growth forms. We also found that high disturbance intensity due to heavy grazing has a strong negative effect on plant coverage rather than species richness in semi-steppe rangelands. This study suggests that proper grazing systems (e.g. rotational system) based on carrying capacity and stocking rate of a rangeland may be helpful for biodiversity conservation, better grazing of livestock, improvement of plant coverage and enhancement of aboveground biomass.


Asunto(s)
Biodiversidad , Desarrollo de la Planta , Biomasa , Ecosistema , Irán , Plantas
20.
Cancer Sci ; 108(10): 1953-1958, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28782898

RESUMEN

Cancer is a polygenic disease characterized by uncontrolled growth of normal body cells, deregulation of the cell cycle as well as resistance to apoptosis. The spectraplakin protein microtubule actin cross-linking factor 1 (MACF1) plays an essential function in various cellular processes, including cell proliferation, migration, signaling transduction and embryo development. MACF1 is also involved in processes such as metastatic invasion in which cytoskeleton organization is a critical element that contributes to tumor progression in various human cancers. Aberrant expression of MACF1 initiates the tumor cell proliferation, and migration and metastasis in numerous cancers, such as breast cancer, colon cancer, lung cancer and glioblastoma. In this review, we summarized the current knowledge of MACF1 and its critical role in different human cancers. This will be helpful for researchers to investigate the novel functional role of MACF1 in human cancers and as a potential target to enhance the efficacy of therapeutic treatment modalities.


Asunto(s)
Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Neoplasias/metabolismo , Empalme Alternativo , Movimiento Celular , Proliferación Celular , Progresión de la Enfermedad , Humanos , Invasividad Neoplásica , Transducción de Señal
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