Search

The ability to predict vegetation cover effects on thermal/water regimes can enhance our understanding of canopy controls on evapotranspiration. The Simultaneous Heat and Water (SHAW) model is a detailed process model of heat and water movement in a snow-residue-soil system. This paper describes provisions added to the SHAW model for vegetation cover and simulation of heat and water transfer through the soil-plant-air continuum. The model was applied to four full years (May 2003-April 2007) of data collected on sparse grassland at Nalaikh in north-eastern Mongolia. Simulated soil temperature and radiation components agreed reasonably well with measured values. The absolute differences between simulated and measured soil temperatures were larger at both the surface layer and deeper layer, but relatively smaller in the layer from 0·8 to 2·4 m. Radiation components were mimicked by the SHAW model with model efficiency (ME) reaching 0·93-0·72. Latent and sensible heat fluxes were simulated well with MEs of 0·93 and 0·87, respectively. The vegetation control on evapotranspiration was investigated by sensitivity experiments of model performance with changing leaf area index (LAI) values but constant of other variables. The results suggest that annual evapotranspiration ranged from 16 to − 22% in response to extremes of doubled and zero LAI. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Neural stem cells (NSC) have tremendous potential for therapeutic regeneration of diseased or traumatized neural tissues, including injured spinal cord. However, transplanted NSC suffer from low cell survival and uncontrolled differentiation, limiting in vivo efficacy. Here, this issue is tackled by delivery through silk-collagen protein hydrogels that are stiffness-matched, stress-relaxing, and shear-thinning. The mechanically-tuned hydrogels protect NSC reprogrammed from fibroblasts (iNSC) initially from injection shear-stress, and enhance long-term survival over 12 weeks. Hydrogel-iNSC treatment alleviates neural inflammation, with reduced inflammatory cells and lesions than NSC-only. The iNSC migrate from the hydrogel into surrounding tissues, secrete up-regulated neurotrophic factors, and differentiate into neural cell subtypes, forming synapses. More serotonergic axons are observed in the lesion cavity, and locomotor functions are improved in hydrogel-iNSC than in iNSC-only. This study highlights the ability of mechanically-tuned protein hydrogels to protect iNSC from the injection stress and severe inflammatory environment, allowing them to differentiate and function to recover the injured spinal cord., (© 2022 Wiley-VCH GmbH.)

Spinal cord injury (SCI) leads to disruption of the blood-spinal cord barrier, hemorrhage, and tissue edema, which impair blood circulation and induce ischemia. Angiogenesis after SCI is an important step in the repair of damaged tissues, and the extent of angiogenesis strongly correlates with the neural regeneration. Various biomaterials have been developed to promote angiogenesis signaling pathways, and angiogenic self-assembling peptides are useful for producing diverse supramolecular structures with tunable functionality. RADA16 (Ac-RARADADARARADADA-NH2), which forms nanofiber networks under physiological conditions, is a self-assembling peptide that can provide mechanical support for tissue regeneration and reportedly has diverse roles in wound healing. In this study, we applied an injectable form of RADA16 with or without the neuropeptide substance P to the contused spinal cords of rats and examined angiogenesis within the damaged spinal cord and subsequent functional improvement. Histological and immunohistochemical analyses revealed that the inflammatory cell population in the lesion cavity was decreased, the vessel number and density around the damaged spinal cord were increased, and the levels of neurofilaments within the lesion cavity were increased in SCI rats that received RADA16 and RADA16 with substance P (rats in the RADA16/SP group). Moreover, real-time PCR analysis of damaged spinal cord tissues showed that IL-10 expression was increased and that locomotor function (as assessed by the Basso, Beattie, and Bresnahan (BBB) scale and the horizontal ladder test) was significantly improved in the RADA16/SP group compared to the control group. Our findings indicate that RADA16 modified with substance P effectively stimulates angiogenesis within the damaged spinal cord and is a candidate agent for promoting functional recovery post-SCI., Competing Interests: Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

Exercise training is a traditional method to maximize remaining function in patients with spinal cord injury (SCI), but the exact mechanism by which exercise promotes recovery after SCI has not been identified; whether exercise truly has a beneficial effect on SCI also remains unclear. Previously, we showed that epigenetic changes in the brain motor cortex occur after SCI and that a treatment leading to epigenetic modulation effectively promotes functional recovery after SCI. We aimed to determine how exercise induces functional improvement in rats subjected to SCI and whether epigenetic changes are engaged in the effects of exercise. A spinal cord contusion model was established in rats, which were then subjected to treadmill exercise for 12 weeks. We found that the size of the lesion cavity and the number of macrophages were decreased more in the exercise group than in the control group after 12 weeks of injury. Immunofluorescence and DNA dot blot analysis revealed that levels of 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) in the brain motor cortex were increased after exercise. Accordingly, the expression of ten-eleven translocation (Tet) family members (Tet1, Tet2, and Tet3) in the brain motor cortex also elevated. However, no macrophage polarization was induced by exercise. Locomotor function, including Basso, Beattie, and Bresnahan (BBB) and ladder scores, also improved in the exercise group compared to the control group. We concluded that treadmill exercise facilitates functional recovery in rats with SCI, and mechanistically epigenetic changes in the brain motor cortex may contribute to exercise-induced improvements.

Axonal regeneration after spinal cord injury (SCI) is difficult to achieve, and no fundamental treatment can be applied in clinical settings. DNA methylation has been suggested to play a role in regeneration capacity and neuronal growth after SCI by controlling the expression of regeneration-associated genes (RAGs). The aim of this study was to examine changes in neuronal DNA methylation status after SCI and to determine whether modulation of DNA methylation with ascorbic acid can enhance neuronal regeneration or functional restoration after SCI. Changes in epigenetic marks (5-hydroxymethylcytosine (5hmC) and 5-methylcytosine (5mC)); the expression of Ten-eleven translocation ( Tet ) family genes; and the expression of genes related to inflammation, regeneration, and degeneration in the brain motor cortex were determined following SCI. The 5hmC level within the brain was increased after SCI, especially in the acute and subacute stages, and the mRNA levels of Tet gene family members (Tet1, Tet2, and Tet3) were also increased. Administration of ascorbic acid (100 mg/kg) to SCI rats enhanced 5hmC levels; increased the expression of the Tet1, Tet2, and Tet3 genes within the brain motor cortex; promoted axonal sprouting within the lesion cavity of the spinal cord; and enhanced recovery of locomotor function until 12 weeks. In conclusion, we found that epigenetic status in the brain motor cortex is changed after SCI and that epigenetic modulation using ascorbic acid may contribute to functional recovery after SCI.

Spinal cord injury (SCI) is a devastating lesion lacking effective treatment options currently available in clinics. The inflammatory process exacerbates the extent of the lesion through a secondary injury mechanism, where proinflammatory classically activated macrophages (M1) are prevalent at the lesion site. However, the polarized alternatively activated anti-inflammatory macrophages (M2) are known to play an important role in wound healing and regeneration following SCI. Herein, we introduce porcine brain decellularized extracellular matrix (dECM) to modulate the macrophages in the injured spinal cord. The hydrogels with collagen and dECM at various dECM concentrations (1, 5, and 8 mg/ml) were used to cultivate primary macrophages and neurons. The dECM hydrogels were shown to promote the polarization of macrophages toward M2 phase and the neurite outgrowth of cortical and hippocampal neurons. When the dECM hydrogels were applied to rat SCI models, the proportion of M1 and M2 macrophages in the injured spinal cord was substantially altered. When received dECM concetration of 5 mg/ml, the expression of molecules associated with M2 (CD206, arginase1, and IL-10) was significantly increased. Consistently, the population of total macrophages and cavity area were substantially reduced in the dECM-treated groups. As a result, the locomotor functions of injured spinal cord, as assessed by BBB and ladder scoring, were significantly improved. Collectively, the porcine brain dECM with optimal concentration promotes functional recovery in SCI models through the activation of M2 macrophages, suggesting the promising use of the engineered hydrogels in the treatment of acute SCI. STATEMENT OF SIGNIFICANCE: Spinal cord injury (SCI) is a devastating lesion, lacking effective treatment options currently available in clinics. Here we delineated that the treatment of injured spinal cord with porcine brain decellularized matrix-based hydrogels for the first time, and could modulate the macrophage polarization and the ultimate functional recovery. When appropriate formulations were applied to a contused spinal cord model in rats, the decellularized matrix hydrogels shifted the macrophages to polarize to pro-regenerative M2 phenotype, decreased the size of lesion cavity, and finally promoted the locomotor functions until 8 weeks following the injury. We consider this work can significantly augment the matrix(biomaterial)-based therapeutic options, as an alternative to drug or cell-free approaches, for the treatment of acute injury of spinal cord., (Copyright © 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Many Mongolian people suffer from non-communicable chronic diseases. In order to plan preventive strategies against such diseases, we designed a community-based prospective cohort study of chronic diseases, called the Moncohort study, in Mongolia. This is the first nationwide large-scale cohort study of chronic diseases. This paper describes the study's rationale, design and methods with baseline data. Mongolian residents aged ⩾40years were selected nationwide from many geographic regions in 2009. Data were collected on demographics, socioeconomic status, lifestyle, and anthropometric and biochemical measurements. In total, 2280 Mongolian residents were registered in the survey. Socioeconomic, lifestyle, anthropometric and biochemical characteristics were differentiated by gender and geographical area in descriptive data. Aging, low social class, physical inactivity and infrequent fruits intake were positively associated with histories of chronic disease in men, while aging was positively associated with histories of chronic disease in women. Factors associated with chronic diseases reveal gender-oriented strategies might be needed for their prevention. Detailed prospective analyses will illustrate the impact of risk factors on chronic diseases and lead to evidence for designing programs aimed at preventing chronic diseases and related disorders in Mongolia., (Copyright © 2016 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.)

Background: Although cardiovascular health is a crucial problem for Mongolian people, little information about metabolic syndrome, which is well known to be associated with the development of cardiovascular disease, is available in Mongolia. The aim of this study was to observe the epidemiological features of metabolic syndrome in a general Mongolian population., Methods: This cross-sectional study was performed in 1911 general Mongolian subjects (717 men, 1194 women), who were ≥40 years old and free of ischemic heart disease, by using a dataset from a nationwide population-based cohort study in Mongolia. The prevalence of metabolic syndrome, as defined by International Diabetes Federation criteria, was determined. Alcohol consumption, smoking habits, and physical activity were evaluated. Education, marital status, income, and occupation were also examined as factors of socioeconomic status (SES). Their association with metabolic syndrome was determined by logistic regression models., Results: The prevalence of metabolic syndrome was significantly higher in women (n=488, 40.6%) than in men (n=138, 19.4%). The prevalence of metabolic syndrome was high, especially in the Khangai region, in women. Moderate-to-high alcohol consumption was a significantly positively associated factor of metabolic syndrome in men [odds ratio (OR)=2.01; 95% confidence interval (CI) 1.15-3.51; adjusted odds ratio (AOR)=2.41; 95% CI 1.31-4.44] and widowed status was a significantly positively associated factor of metabolic syndrome in women (OR=1.61, 95% CI 1.18-2.18; AOR=1.49, 95% CI 1.07-2.08)., Conclusions: Metabolic syndrome was prevalent in women compared with men among Mongolian adults. Preventive strategies aimed at men with a higher alcohol consumption and women with widowed status may help reduce metabolic syndrome, thereby improving cardiovascular health conditions in Mongolia.

The regression tree method is used to upscale evapotranspiration (ET) measurements at eddy-covariance (EC) towers to the grassland ecosystems over the Dryland East Asia (DEA). The regression tree model was driven by satellite and meteorology datasets, and explained 82% and 76% of the variations of ET observations in the calibration and validation datasets, respectively. The annual ET estimates ranged from 222.6 to 269.1 mm yr(-1) over the DEA region with an average of 245.8 mm yr(-1) from 1982 through 2009. Ecosystem ET showed decreased trends over 61% of the DEA region during this period, especially in most regions of Mongolia and eastern Inner Mongolia due to decreased precipitation. The increased ET occurred primarily in the western and southern DEA region. Over the entire study area, water balance (the difference between precipitation and ecosystem ET) decreased substantially during the summer and growing season. Precipitation reduction was an important cause for the severe water deficits. The drying trend occurring in the grassland ecosystems of the DEA region can exert profound impacts on a variety of terrestrial ecosystem processes and functions.

Background: Kawasaki disease (KD) has been reported in many countries. However, the incidence of KD in Mongolia is not known. This is the first report of incident cases of KD in Mongolia, which were identified using data from 2 nationwide surveys., Methods: Two nationwide retrospective surveys were conducted: medical histories were collected from patients aged 0 to 16 years who were hospitalized countrywide between 1996 and 2008. Hospital records for these patients were also reviewed. Nationwide training seminars on KD were conducted before each survey., Results: For the nationwide surveys, the participation rates among all hospitals with pediatric wards were 97% and 94%. Inpatient medical histories from 1996 through 2008 were reviewed, and, among children younger than 16 years, 9 patients with KD were investigated. The age of KD patients ranged from 1.4 to 14 years; 7 of 9 patients were male. Six (67%) patients fulfilled all 6 clinical diagnostic criteria; the other 3 (33%) were defined as having KD based on the presence of 5 such criteria. Fever persisting 5 or more days, bilateral conjunctival congestion, and changes of the lips and oral cavity were the most common symptoms, and cervical lymphadenopathy was the least common symptom. Cardiac sequelae developed in 5 of the patients, 4 of whom were older than 10 years., Conclusions: The results of these nationwide surveys reveal that KD cases do exist in Mongolia. However, knowledge of KD among Mongolian pediatricians is likely to be poor. Thus, there is a need to augment their understanding to improve management of KD patients. Further studies are crucial to clarify the epidemiologic characteristics of KD in Mongolia.

Steppe desertification due to vehicle travel is a severe environmental issue in Mongolia. We studied natural vegetation recovery on abandoned vehicle tracks in the central Mongolia steppe through vegetation surveys and stable isotopic techniques. The following issues were addressed: (i) invasion of pioneering plant species, (ii) alteration of soil surface features, and (iii) contribution of revegetated plants to soil organic matter (SOM). The pioneering plant species that firstly invaded the abandoned tracks are those that could germinate, root and survive in the compacted track surface. Salsola collina is one of these candidate plants. Due to revegetation, soil surface hardness was reduced. With the improvement of surface microenvironmental conditions, other plants began to colonize and establish; con-comitantly species richness and species diversity increased. Carbon isotope ratios of SOM at the top surface layer indicated that C4 -derived carbon contributed more to SOM in the early phase of recovery and decreased with further recovery.