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1.
J Orthop Res ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38751166

RESUMEN

Craniectomy is a lifesaving procedure to alleviate dangerously high intracranial pressure by removing a bone flap from the calvarium. However, the osteointegration of reimplanted bone flap with the existing bone tissue is still a clinical challenge. Hyperbaric oxygen (HBO) therapy has shown efficacy in promoting bone repair and could be a promising treatment for accelerating postoperative recovery. However, the specific cell types that are responsive to HBO treatment are not well understood. In this study, we created a murine model of craniectomy, with reimplantation of the cranial flap after 1 week. The effects of HBO treatment on bone formation and blood vessel formation around reimplanted bone were examined by micro-computed tomography, histological staining, and immunofluorescence staining. Single-cell RNA sequencing (scRNAseq) was utilized to identify key cell subtypes and signaling pathways after HBO treatment. We found that HBO treatment increased bone volume around reimplanted cranial flaps. HBO also increased the volume of Osterix-expressing cells and type H vessels. scRNAseq data showed more mature osteoblasts and endothelial cells, with higher expressions of adhesion and migration-related genes after HBO treatment. Cell-cell interaction analysis revealed a higher expression level of genes between mature osteoblasts and endothelial cells from the angiopoietin 2-integrin α5ß1 pathway. Taken together, HBO therapy promotes the healing process of craniectomy by regulating the crosstalk between vascular endothelial cells and osteogenic cells. These findings provide evidence in a preclinical model that HBO therapy enhances osteointegration by regulating angiogenesis-osteogenesis coupling, providing a scientific basis for utilizing HBO therapy for accelerating postoperative recovery after craniectomy.

2.
Dent J (Basel) ; 11(10)2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37886919

RESUMEN

The aim of this systematic review is to describe and identify the prospects of ß-Tricalcium Phosphate (ß-TCP) as an alveolar bone grafting (ABG) material in cleft lip/palate (CL/P) or alveolar bone cleft defects. A systematic review protocol based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 (PRISMA 2020) was drafted. The literature search was conducted using MEDLINE/PubMed, Web of Science/ISI Web of Knowledge, Scopus, and the Cochrane Library, with English as the inclusion criterion and no publication year limits. The keywords yielded a total of 5824 publications. After removing duplicates and non-English articles, there were 3196 suitable articles available for evaluation. Subsequently, 1315 studies remained after reviewing titles and abstracts. Furthermore, 85 full articles were assessed for eligibility. After reading the complete texts of those papers, 20 were eventually selected that matched the inclusion requirements. Thirteen out of the twenty studies included in this systematic review were deemed to have a low risk of bias; one had a high risk of bias; and six had a moderate risk of bias due to not reporting randomization. ß-TCP, when used as an ABG material, is biocompatible, visible, practical, offers a less invasive procedure, and does not interfere with orthodontic treatment. Synthetic ß-TCP for ABG can be an alternative to autologous bone grafts under certain terms and conditions. The efficacy of ß-TCP for ABG in CL/P or alveolar bone cleft defects can be enhanced through a tissue engineering approach that combines ß-TCP with growth factors, mesenchymal stem cells, or other graft materials, along with modifications to ß-TCP's physical properties.

3.
Artículo en Inglés | MEDLINE | ID: mdl-35805679

RESUMEN

The accumulation of nitrogen in groundwater in the industrial plots, especially the high ammonium, can result in a serious threat to the groundwater system in the urban area. This study monitored the dissolved inorganic nitrogen (DIN) of the polluted groundwater four times in one year in a retired nitrogenous fertilizer plant site with a production history of nearly 40 years, to analyze the spatial-temporal characteristics of DIN species (NH4+-N, NO3−-N, and NO2−-N) and the effects of groundwater environment on their transfer and transformation. The results showed that NH4+-N (<0.025 to 1310 mg/L) was the main DIN species (61.38−76.80%) with low mobility, whereas the concentration of NO3−-N and NO2−-N was 0.15−146 mg/L and <0.001−12.4 mg/L, accounting for 22.34−36.07% and 0.53−2.83% of total DIN, respectively. The concentration and proportion of NO3−-N and NO2−-N showed an upward trend with time, posing a threat to the safety of surrounding groundwater, and their high spatial-temporal variation was related to the morphological transformation and the transport. In the wet season, the pH and redox condition benefited the nitrification, and NO3−-N easily migrated from the deep soil solution to groundwater, hence the NO3−-N can be accumulated. Therefore, the analysis of species and behaviors of DIN in shallow groundwater is indispensable for environmental risk assessment.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Fertilizantes/análisis , Nitratos/análisis , Nitrógeno/análisis , Dióxido de Nitrógeno/análisis , Contaminantes Químicos del Agua/análisis
4.
Appl Ergon ; 102: 103760, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35395580

RESUMEN

This study aimed to examine the effects of body posture, typing style and device type on upper limb and shoulder muscle activities, typing performance and perceived workload while typing with mobile devices. Participants were asked to type with two mobile devices (i.e., a tablet and a smartphone) under three postures and in two typing styles. Muscle activity was recorded for four upper limb and shoulder muscles on both sides with surface electromyography. Results showed that body posture and typing style yielded significant effects on tying performance, perceived workload, and muscle activities in the forearm, upper arm and shoulder. Typing with a tablet was more accurate and had greater muscle activities in the upper arm and forearm on both sides than typing with a smartphone. The findings may be useful in developing evidence-based guidelines for the wise use of mobile devices and for the prevention of risks for musculoskeletal disorders.


Asunto(s)
Hombro , Carga de Trabajo , Electromiografía , Humanos , Músculo Esquelético/fisiología , Postura/fisiología , Hombro/fisiología , Extremidad Superior/fisiología
5.
Bull Environ Contam Toxicol ; 108(3): 555-562, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35072764

RESUMEN

Rare earth elements (REE) geochemistry can reveal the environmental information of solutes in river systems because REE is sensitive to hydro-geochemical changes in the earth's surface environment. This work collected the river water samples from Zhujiang River (the largest river in South China) to investigate the concentration, fractionation, and environmental implication of dissolved REE. The total dissolved REE (∑REE) concentrations are similar in different seasons. In mid-lower reaches, the REE concentrations tend to increase corresponding to low pH, and the normalized ratios of lanthanum (La) to ytterbium (Yb) are higher, suggesting weak fractionation between light REE and heavy REE. Compared to the previous study in 2000, the higher samarium (Sm) and europium (Eu) concentrations are most likely influenced by stronger water/particle interaction. These findings provide preliminary information for REE cycle in the surface environment.


Asunto(s)
Ríos , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Europio , Contaminantes Químicos del Agua/análisis
6.
Environ Res ; 200: 111452, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34111438

RESUMEN

Iron (Fe) is an essential element for bio-physiological functioning terrestrial organisms, in particular of aquatic organisms. It is therefore crucial to understand the aquatic iron cycle and geochemical characteristics, which is also significant to obtain the key information on earth-surface evolution. The stable iron isotopic composition (δ56Fe) of the dissolved fraction is determined in the Mun River (main tributary of Mekong River), northeast Thailand to distinguish the human and nature influenced riverine iron geochemical behavior. The results show that dissolved Fe concentration ranges from 8.04 to 135.27 µg/L, and the δ56Fe ranges from -1.34‰ to 0.48‰, with an average of 0.23‰, 0.14‰ and -0.15‰ in the upper, middle and lower reaches, respectively. The δ56Fe values of river water are close to that of the bulk continental crust and other tropical rivers. The correlations between δ56Fe and Fe, Al, and physicochemical parameters show mixing processes of different Fe end-members, including the rock weathering end-member (low Fe/Al ratio and high δ56Fe), the urban activities end-member (high Fe/Al ratio and moderate δ56Fe), and a third end-member with probable sources from the Chi River and reservoir. For the most river water samples, the primary contribution is attributed to rock weathering, and the second is urban activities (only a few samples are from the upper and middle reaches). Thus, Fe isotopes could be employed as a proxy to identify and quantify the natural and anthropogenic contributions, respectively. These findings also provide data support for the scientific management of water resources in the Mun River catchment and other large tropical rivers.


Asunto(s)
Ríos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Agua Dulce , Humanos , Hierro , Isótopos , Contaminantes Químicos del Agua/análisis
7.
PeerJ ; 9: e10853, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33665023

RESUMEN

Forty-eight suspended particulate matter (SPM) samples were collected from the Mun River, northeast Thailand and its junction with the Mekong River, to investigate the relationship between the distribution of rare earth elements (REE) in SPM and the soils in the watershed. The total REE contents (∑REE) in SPM in the Mun River ranged from 78.5 to 377.8 mg/kg with the average of 189.3 mg/kg, which was lower than ∑REE of 222.3 mg/kg at the Mekong River (one sample at junction). The Post Archean Australia Shale (PAAS)-normalized ratios of light REE (LREE), middle REE (MREE) and heavy REE (HREE) were averaged to 1.0, 1.3 and 1.0, which showed a clear enrichment in MREE. In short, along the Mun River, the REE contents in SPM were decreasing, and the PAAS-normalized patterns of REE showed gradually flat. The REE content in SPM and soils are highest in the upper catchment, indicating that soil/bedrock is the most important source of REE in SPM. Additionally, the positive Eu anomaly was enhanced by the higher Ca content in SPM (R = 0.45), which may be caused by more feldspars or carbonates with Ca and Eu substituting Ca. The results present the REE behaviors of SPM in the Mun River and relationship between REE in SPM and soil/bedrock, the findings may support the other studies in catchment weathering.

8.
Artículo en Inglés | MEDLINE | ID: mdl-31948052

RESUMEN

To identify whether the iron (Fe) mining area in the Jiulongjiang River basin (JRB) has an influence on the mercury in the forest soil, the spatial distribution patterns of mercury's behavior on different controlling factors were analyzed, and a potential ecological risk assessment was done. A total of 107 soil samples were collected from two forest soil profiles, one profile near the Fe mining area and the other far from it. The soil near the mining area had a moderate potential ecological risk with high Fe content rich in the upper layer of soil (<70 cm), whereas soil collected far from the mining area had a low potential ecological risk. These results indicated that the rise of iron content in the soil near the mining area was beneficial to the enrichment of mercury, probably causing damage to the forest ecosystem. Both soil organic carbon (SOC) and Fe content have strong positive correlations with THg content, controlling the mercury behavior in the upper layer (<70 cm) and a lower layer (>70 cm) of soil, respectively. The high Fe content in the upper layer of soil will compete for the adsorption of mercury by SOC, leading to the poor correlation between SOC and THg.


Asunto(s)
Hierro/química , Mercurio/química , Compuestos Orgánicos/química , Contaminantes del Suelo/química , Suelo/química , China , Ecología , Ecosistema , Monitoreo del Ambiente/métodos , Bosques , Mercurio/análisis , Minería , Ríos , Contaminantes del Suelo/análisis
9.
Artículo en Inglés | MEDLINE | ID: mdl-31817498

RESUMEN

Climate changes and other human activities have substantially altered the hydrological cycle with respect to elevation. In this study, longitudinal patterns in the stable isotopic composition (δ2H and δ18O) of Lancang River water, originating from the Qinghai-Tibetan Plateau, are presented, and several controlling factors in the wet season are hypothesized. Lancang River water δ2H (-145.2‱ to -60.7‱) and δ18O (-18.51‱ to -8.49‱) were low but close to those of the Global Meteoric Water Line. In the upper reaches of the river, δ2H decreased longitudinally, potentially due to groundwater inputs and melting ground ice in the headwater zone and to an increasing proportion of glacier meltwater with decreasing elevation. In the middle reaches of the river, δ2H values increased slowly moving downstream, likely due to shifts in precipitation inputs, as evidenced by the isotopic composition of tributaries to the main stream. In the lower reaches of the river, the isotopic composition was relatively invariant, potentially related to the presence of large artificial reservoirs that increase the water resident time. The results reveal different hydrological patterns along an alpine river in central Asia associated with both natural and anthropogenic processes. Understanding the degree and type of human interference with the water cycle in this region could improve water management and water security.


Asunto(s)
Monitoreo del Ambiente/métodos , Agua Dulce/química , Hidrógeno/análisis , Hidrología , Isótopos de Oxígeno/análisis , China , Agua Subterránea , Cubierta de Hielo , Ríos , Estaciones del Año
10.
Artículo en Inglés | MEDLINE | ID: mdl-31652747

RESUMEN

In order to understand the water cycle and assess the water quality for irrigation purposes in the Upper Pi River Basin (UPRB), which is the northern slope of the Dabie Mountains, 68 surface water and groundwater samples were collected and analyzed for H-O isotopes and hydrochemistry during the high-flow season in 2017 and 2018. The results show that ranges of hydrogen and oxygen isotopic composition (δ2H: -68.8‱ to -40.8‱, δ18O: -10.05‱ to -5.05‱) are controlled by the medium latitude and high altitude of the UPRB. Among different types of water, the δ2H and δ18O values can be ordered as follows: reservoir water < spring water ≈ river water < pond water. The water of the upstream medium and small reservoir is enriched with lighter isotopes that is likely related to more exchange with rainwater and less residence time; however, large reservoirs are similar to the upstream river and spring in terms of the H-O isotopic composition. Hydro-chemical facies are dominated by the Ca-HCO3 type in the UPRB, which reflects fresh recharged water from rainfall, and few samples are of the Ca-Cl type that is caused by intensive evaporation. The water quality for irrigation purposes was also evaluated. According to the Wilcox diagram, United States Salinity Laboratory (USSL) diagram, magnesium hazard, and Kelly's ratio, all water samples have been considered suitable for irrigation water.


Asunto(s)
Agua Dulce/química , Agua Subterránea/química , Isótopos de Oxígeno/análisis , Calidad del Agua , China , Agua Dulce/análisis , Agua Subterránea/análisis , Estaciones del Año
11.
Artículo en Inglés | MEDLINE | ID: mdl-31540022

RESUMEN

Dissolved inorganic carbon isotope composition (δ13CDIC), together with major ion concentrations were measured in the Mun River and its tributaries in March 2018 to constrain the origins and cycling of dissolved inorganic carbon. In the surface water samples, the DIC content ranged from 185 to 5897 µmol/L (average of 1376 µmol/L), and the δ13CDIC of surface water ranged from -19.6‱ to -2.7‱. In spite of the high variability in DIC concentrations and partial pressure of carbon dioxide (pCO2), the δ13CDIC values of the groundwater were relatively consistent, with a mean value of -16.9 ± 1.4‱ (n = 9). Spatial changes occurred in the direction and magnitude of CO2 flux through water-air interface (FCO2). In the dry season, fluxes varied from -6 to 1826 mmol/(m2·d) with an average of 240 mmol/(m2·d). In addition to the dominant control on hydrochemistry and dissolved inorganic carbon isotope composition by the rock weathering, the impacts from anthropogenic activities were also observed in the Mun River, especially higher DIC concentration of waste water from urban activities. These human disturbances may affect the accurate estimate contributions of carbon dioxide from tropical rivers to the atmospheric carbon budgets.


Asunto(s)
Ciclo del Carbono , Carbono/análisis , Ríos/química , Agricultura , Dióxido de Carbono/análisis , Isótopos de Carbono/análisis , Agua Subterránea/química , Estaciones del Año , Tailandia
12.
Artículo en Inglés | MEDLINE | ID: mdl-30813409

RESUMEN

C and N species, including dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), dissolved organic nitrogen (DON), NO3- and NH4⁺ contents in 57 river water samples collected from the Mun River of Thailand were measured to determine the relationships between these dissolved load species and their impacts on the environment. DOC values varied between 1.71 and 40.08 mg/L, averaging 11.14 mg/L; DON values ranged from 0.20 to 1.37 mg/L, with an average value of 0.48 mg/L; NO3--N values averaged 0.18 mg/L; and NH4⁺-N values averaged 0.15 mg/L. DOC contents increased while DON and NO3- values decreased along the flow direction. The concentrations of NH4⁺ maintained the same level in the whole watershed. DOC and DON values exhibited clearly higher concentrations in comparison with other rivers worldwide and were inextricably linked with anthropogenic inputs. The relationships of DOC, DON, and anthropogenic ions imply that there are two different anthropogenic sources (industrial activities and agricultural activities) of the dissolved load in the Mun River watershed. The limited correlations between the DON, NO3-, and NH4⁺ indicate that the N species are not dominated by a single factor, and reciprocal transformations of riverine N pool are complex. Based on the environmental water quality standard reported by the EC (European Communities) and the World Health Organization, assessments of the water quality using the parameters of pH, dissolved oxygen (DO), NO3-, NH4⁺, and TN (total nitrogen) in the Mun River were conducted. The results demonstrate that the river water faces potential environmental pollution, and anthropogenic inputs endanger local water quality and the aquatic community. Therefore, the local government should restrict and reduce the anthropogenic inputs discharged in to rivers, and launch long-term monitoring of water quality.


Asunto(s)
Carbono/análisis , Nitrógeno/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Calidad del Agua , Agricultura , Monitoreo del Ambiente , Humanos , Industrias , Tailandia , Calidad del Agua/normas
13.
Artículo en Inglés | MEDLINE | ID: mdl-30717400

RESUMEN

This study focuses on the chemical weathering process under the influence of human activities in the Jiulongjiang River basin, which is the most developed and heavily polluted area in southeast China. The average total dissolved solid (TDS) of the river water is 116.6 mg/L and total cation concentration ( TZ + ) is 1.5 meq/L. Calcium and HCO 3 - followed by Na + and SO 4 2 - constitute the main species in river waters. A mass balance based on cations calculation indicated that the silicate weathering (43.3%), carbonate weathering (30.7%), atmospheric (15.6%) and anthropogenic inputs (10.4%) are four reservoirs contributing to the dissolved load. Silicates (SCW) and carbonates (CCW) chemical weathering rates are calculated to be approximately 53.2 ton/km²/a and 15.0 ton/km²/a, respectively. When sulfuric and nitric acid from rainfall affected by human activities are involved in the weathering process, the actual atmospheric CO 2 consumption rates are estimated at 3.7 × 105 mol/km²/a for silicate weathering and 2.2 × 105 mol/km²/a for carbonate weathering. An overestimated carbon sink (17.4 Gg C / a ) is about 27.0% of the CO 2 consumption flux via silicate weathering in the Jiulongjiang River basin, this result shows the strong effects of anthropogenic factors on atmospheric CO 2 level and current and future climate change of earth.


Asunto(s)
Carbonatos/química , Actividades Humanas , Ríos/química , Silicatos/química , Atmósfera/análisis , Dióxido de Carbono/análisis , Secuestro de Carbono , Carbonatos/análisis , China , Monitoreo del Ambiente , Silicatos/análisis , Tiempo (Meteorología)
14.
Artículo en Inglés | MEDLINE | ID: mdl-30563145

RESUMEN

In this study, the concentration of eight dissolved heavy metals (Ti, Cr, Mn, Fe, Ni, Mo, Sb, and Ba) in 42 water samples from the Jiulongjiang River, southeast China, were determined by inductively coupled plasma mass spectrometry (ICP-MS). Multivariate statistical methods, including correlation analysis (CA) and factor and principal component analysis (FA/PCA), were analyzed to identify the sources of the elements. Water quality index (WQI) and health risk assessment, including hazard quotient (HQ) and hazard index (HI), were used to evaluate water quality and the impacts on human health. Our results were compared with the drinking water guidelines reported by China, the World Health Organization (WHO), and the United States Environmental Protection Agency (US EPA), revealing that Ti, Mn, and Sb were not within approved limits at some sites and might be the main pollutants in the drainage basin. Based on the spatial distributions, Ti, Mn, Fe, Ni, and Mo showed good similarity, indicating that they might come from similar sources along the river. The CA results also showed that Ti, Mn, Fe, Ni, and Mo had a high correlation coefficient. The FA/PCA results identified three principal components (PC) that accounted for 79.46% of the total variance. PC 1 suggested that a mixed lithogenic and urban land source contributed to Ti, Mn, Fe, Ni, and Mo; PC 2 showed that Cr, Ni, and Mo were influenced by the discharge of industrial effluents; Sb had a strong loading on PC 3, which was controlled by mining activities. The results of the WQI indicated that the water in the Jiulongjiang River was basically categorized as excellent water, but the water quality levels in site W5 and N4 were poorer due to urban land use. Hazard quotient and HI values showed that Sb was a potential threat to human health, indicating that preventive actions should be considered in regard to mining activities in the upper reaches of Beixi stream.


Asunto(s)
Metales Pesados/análisis , Minería , Ríos/química , Contaminantes del Agua/análisis , China , Agua Potable , Monitoreo del Ambiente/métodos , Humanos , Medición de Riesgo , Calidad del Agua
15.
Cancer Epidemiol Biomarkers Prev ; 11(1): 113-9, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11815408

RESUMEN

Epidemiological evidence suggests a potential role for vitamin D in colon cancer prevention. Vitamin D, absorbed from the intestine or derived from solar ultraviolet light, is metabolized in the liver to 25-hydroxyvitamin D (25-OH D(3)). Previous studies examining effects of vitamin D upon carcinogenesis have focused upon the active metabolite 1,25-dihydroxyvitamin D [1,25-(OH)(2) D(3)], which interacts with nuclear vitamin D receptors in several organs. Until recently, the metabolism of 25-OH D(3) to 1,25-(OH)(2) D(3) was believed to occur only in the kidney, but more recent studies have shown that 25-OH D(3) conversion to 1,25-(OH)(2) D(3) can occur in other tissues. We examined the association between fasting levels of 25-OH D(3), 1,25-(OH)(2) D(3), and BsmI polymorphism of the vitamin D receptor (VDR) gene with indices of colonic epithelial cell proliferation and differentiation in a chemoprevention study, after giving vitamin D or calcium and taking rectal biopsies that were incubated with bromodeoxyuridine. Vitamin D receptor polymorphism was determined by genotyping of the 3' BsmI polymorphism in intron eight of the VDR gene. No significant changes in cell proliferation or in differentiation were found in subjects between study start and end. However, fasting serum levels of 25-OH D(3) showed a highly significant decrease with whole crypt labeling index and the size of the proliferative compartment (phi h). There was no correlation between serum levels of 1,25-(OH)(2) D(3) and the proliferative parameters. Calcium supplementation induced a significant effect upon the relationship between serum 25-OH D(3) and rectal epithelial cell labeling index and phi h when studied by covariance analysis without a relationship with 1,25-(OH)(2) D(3) levels. VDR genotype did not influence the effects of serum 25-OH D(3) or serum 1,25-(OH)(2) D(3) levels upon proliferation. These data suggest that there might be a local effect of 25-OH D(3) on colonic epithelial cells through conversion of 25-OH D(3) to 1,25-(OH)(2) D(3). Subsequent studies have demonstrated the presence of 1alpha-hydroxylase mRNA in normal colorectal epithelium and in colorectal cancer. Thus, vitamin D may have an important role in determining the effects of calcium on colorectal epithelial proliferation and may explain some of the discrepancies found previously in studies that examine the direct role of calcium on the colorectal epithelium.


Asunto(s)
Calcifediol/sangre , Calcitriol/administración & dosificación , Colecalciferol/administración & dosificación , Células Epiteliales/efectos de los fármacos , Adulto , Anciano , Análisis de Varianza , División Celular/efectos de los fármacos , Quimioprevención , Neoplasias del Colon/prevención & control , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Mucosa Intestinal/efectos de los fármacos , Masculino , Persona de Mediana Edad , Probabilidad , Estudios Prospectivos , Valores de Referencia , Sensibilidad y Especificidad
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