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Serious arsenic (As) contaminations could commonly result from the oxidative dissolution of As-containing sulfide minerals, such as arsenopyrite (FeAsS). Pyrite (Py) and calcite (Cal) are two typically co-existing reactive minerals and represent different geological scenarios. Previous studies have shown that a high proportion of Py can generate a stronger galvanic effect and acid dissolution, thereby significantly promoting the release of arsenic. However, this conclusion overlooks calcite's antagonistic effect on the release of As in the natural environment. That antagonistic effect could remodel the linear relationship of pyrite on the oxidative dissolution of arsenopyrite, thus altering the environmental risk of As. We examined As release from arsenopyrite along a gradient of Py to Cal molar ratios (Py:Cal). The results showed that the lowest As release from arsenopyrite was surprisingly found in co-existing Py and Cal systems than in the singular Cal system, let alone in the singular Py system. This phenomenon indicated an interesting possibility of Py assistance to Cal inhibition of As release, though Py has always been regarded as a booster, also evidenced in this research, for As release from arsenopyrite. In singular systems of Py and Cal, As continued to be released for 60 days. However, in co-existing Py and Cal systems, As was released non-linearly in three stages over time: initial release (0-1 Day), immobilization (1-15 Days), and subsequent re-release (>15 Days). This is a new short-term natural attenuation stage for As, but over time, this stage gradually collapses. During the re-release stage (> 15 Days), a higher molar ratio of Py:Cal (increasing from 1:9 to 9:1) results in a lower rate constant k (mg·L-1·h-1) of As release (range from 0.0011 to 0.0002), and a higher abundance of secondary minerals formed (up to 26 mg/g goethite and hematite at Py: Cal=9:1). This demonstrates that increasing the Py:Cal molar ratio results in the formation of more secondary minerals which compensate for the higher potential antagonistic mechanisms generated by pyrites, such as acid dissolution and galvanic effect. These results explain the mechanisms of the high-risk characteristics of As both in acidic mine drainage and karst aquifers and discover the lowest risk in pyrite and calcite co-existing regions. Moreover, we emphasize that reactive minerals are important variables that can't be ignored in predicting As pollution in the future.
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Arsénico , Arsenicales , Carbonato de Calcio , Compuestos de Hierro , Hierro , Minerales , Sulfuros , Minerales/química , Sulfuros/química , Compuestos de Hierro/química , Arsenicales/química , Carbonato de Calcio/química , Hierro/química , Solubilidad , Contaminantes Químicos del Agua/química , Oxidación-ReducciónRESUMEN
Biological aqua crust (biogenic aqua crust-BAC) is a potentially sustainable solution for metal(loid) bioremediation in global water using solar energy. However, the key geochemical factors and underlying mechanisms shaping microbial communities in BAC remain poorly understood. The current study aimed at determining the in situ metal(loid) distribution and the key geochemical factors related to microbial community structure and metal(loid)-related genes in BAC of a representative Pb/Zn tailing pond. Here we showed that abundant metal(loid)s (e.g. Pb, As) were co-distributed with Mn/Fe-rich minerals (e.g. biogenic Mn oxide, FeOOH) in BAC. Biogenic Mn oxide (i.e. Mn) was the most dominant factor in shaping microbial community structure in BAC and source tailings. Along with the fact that keystone species (e.g. Burkholderiales, Haliscomenobacter) have the potential to promote Mn ion oxidization and particle agglomeration, as well as Mn is highly associated with metal(loid)-related genes, especially genes related to As redox (e.g. arsC, aoxA), and Cd transport (e.g. zipB), biogenic Mn oxides thus effectively enhance metal(loid) remediation by accelerating the formation of organo-mineral aggregates in biofilm-rich BAC system. Our study indicated that biogenic Mn oxides may play essential roles in facilitating in situ metal(loid) bioremediation in BAC of mine drainage.
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Compuestos de Manganeso , Metales Pesados , Microbiota , Manganeso , Plomo , Bacterias/genética , Óxidos , MineralesRESUMEN
High levels of Cr(III) are hosted in Fe (oxyhydr)oxides in soils derived on (ultra)mafic rocks, which can pose potential risks to the environment. Organic acids can cause the solubilization of Fe (oxyhydr)oxides and the release of Cr(III). However, the release behaviors of Cr(III) from Fe (oxyhydr)oxides by organic acids and its main factors remain unclear. This study investigates the speciation of Cr released from Cr(III)-substituted goethite in the presence of citrate and oxalate and the effects of pH (3-7). Batch experiments showed that Fe(III) and Cr(III) dissolution were significantly enhanced by citrate and oxalate, and the extent of dissolution was negatively correlated with pH. When at relatively high pH (5-7), AF4-ICP-MS results revealed that large proportions of dissolved Fe (>58 %) and Cr (18 %-73 %) were presented in the form of Cr(III)-citrate colloids in the sizes of 1-125 nm and 125-350 nm. Further, FTIR and cryogenic XPS characterization demonstrated that the formation of·Cr(III)-citrate colloids was attributed to the adsorption and complexation of citrate on the substituted goethite surface. However, Cr was mainly released as soluble Cr(III)-organic complexes when presented at pH 3. While low pH inhibited the formation of Cr(III)-organic colloids, it promoted the release of Cr by facilitating the dissociation of surface Cr(III)-organic complexes. In addition, the incorporation of Ni(II) in Cr(III)-substituted goethite weakened the adsorption of organic acid by shortening the crystal size of goethite, thus significantly inhibiting the formation of Cr(III)-organic complexes and colloids. This study confirms the formation of Cr(III)-organic acid colloids and highlights the importance of pH on Cr release behavior, which is essential for evaluating Cr transport and fate in soils with high background values.
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Uncontrolled bleeding is one of the leading causes of human mortality. Existing hemostatic materials or techniques cannot meet the clinical requirements for safe and effective hemostasis. The development of novel hemostatic materials has always been of great interest. Chitosan hydrochloride (CSH), a derivative of chitin, is extensively used on wounds as an antibacterial and hemostatic agent. However, the formation of intra- or intermolecular hydrogen bonds between hydroxyl and amino groups limits its water solubility and dissolution rate and affects its effectiveness in promoting coagulation. Herein, we covalently grafted aminocaproic acid (AA) to the hydroxyl and amino groups of CSH via ester and amide bonds, respectively. The solubility of CSH in water (25 °C) was 11.39 ± 0.98 % (w/v), whereas the AA-grafted CSH (CSH-AA) reached 32.34 ± 1.23 % (w/v). Moreover, the dissolution rate of CSH-AA in water was 6.46 times higher than that of CSH. Subsequent studies proved that CSH-AA is non-toxic, biodegradable, and has superior antibacterial and hemostatic properties to CSH. Additionally, anti-plasmin activity can be exerted by the dissociated AA from the CSH-AA backbone, which can help to lessen secondary bleeding.
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Quitosano , Hemostáticos , Humanos , Hemostáticos/química , Quitosano/química , Ácido Aminocaproico/farmacología , Hemorragia/tratamiento farmacológico , Hemorragia/prevención & control , Hemostasis , Antibacterianos/químicaRESUMEN
Chromium (Cr) is an expression toxic metal and is seriously released into the soil environment due to its extensive use and mining. Basalt is an important Cr reservoir in the terrestrial environment. Cr in paddy soil can be enriched by chemical weathering. Therefore, basalt-derived paddy soils contain extremely high concentrations of Cr and can enter the human body through the food chain. However, the water management conditions' effect on the transformation of Cr in basalt-derived paddy soil with high geological background values was less recognized. In this study, a pot experiment was conducted to investigate the effects of different water management treatments on the migration and transformation of Cr in a soil-rice system at different rice growth stages. Two water management treatments of continuous flooding (CF) and alternative wet and dry (AWD) and four different rice growth stages were set up. The results showed that AWD treatment significantly reduced the biomass of rice and promoted the absorption of Cr in rice plants. During the four growth periods, the root, stem and leaf of rice increased from 11.24-16.11 mg kg-1, 0.66-1.56 mg kg-1 and 0.48-2.29 mg kg-1 to 12.43-22.60 mg kg-1, 0.98-3.31 mg kg-1 and 0.58-2.86 mg kg-1, respectively. The Cr concentration in roots, stems and leaves of AWD treatment was 40%, 89% and 25% higher than CF treatment in the filling stage, respectively. The AWD treatment also facilitated the potential bioactive fractions conversion to the bioavailable fraction, compared with the CF treatment. In addition, the enrichment of iron-reducing bacteria and sulfate-reducing bacteria with AWD treatment also provided electron iron for the mobilization of Cr, thus affecting the migration and transformation of Cr in the soil. We speculated that the reason for this phenomenon may be the bioavailability of Cr was affected by the biogeochemical cycle of iron under the influence of alternating redox. This indicates that AWD treatment may bring certain environmental risks in contaminated paddy soil with high geological background, and it is necessary to be aware of this risk when using water-saving irrigation to plant rice.
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Chromium (Cr) accumulating in soil caused serious pollution to cultivated land. At present, nano zero-valent iron (nZVI) is considered to be a promising remediation material for Cr-contaminated soil. However, the nZVI impact on the behavior of Cr in the soil-rice system under high natural geological background value remains unknown. We studied the effects of nZVI on the migration and transformation of Cr in paddy soil-rice by pot experiment. Three different doses of nZVI (0, 0.001 % and 0.1 % (w/w)) treatments and one dose of 0.1 % (w/w) nZVI treatment without plant rice were set up. Under continuous flooding conditions, nZVI significantly increased rice biomass compared with the control. At the same time, nZVI significantly promoted the reduction of Fe in the soil, increased the concentration of oxalate Fe and bioavailable Cr, then facilitated the absorption of Cr in rice roots and the transportation to the aboveground part. In addition, the enrichment of Fe(III)-reducing bacteria and sulfate-reducing bacteria in soil provided electron donors for Cr oxidation, which helps to form bioavailable Cr that is easily absorbed by plants. The results of this study can provide scientific basis and technical support for the remediation of Cr -polluted paddy soil with high geological background.
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Cromo , Restauración y Remediación Ambiental , Oryza , Contaminantes del Suelo , Cromo/análisis , Hierro/química , Oryza/química , Gestión de Riesgos , Suelo , Contaminantes del Suelo/análisisRESUMEN
Hexavalent chromium (Cr(VI)) is more readily taken up by plants than trivalent chromium (Cr(III)) due to its similar chemical structure to phosphate and sulfate. In paddy soils, Cr(VI) of natural origin are mainly produced from Cr(III) oxidized by O2 and Mn(III/IV) oxides, which are affected by rice radial oxygen loss (ROL) and Mn(II)-oxidizing microorganisms (MOM). However, little is known about the effect of ROL and Mn abundance on rice Cr uptake. Here, we investigated the effects on Cr(VI) generation and the subsequent Cr uptake and accumulation with the involvement of two rice cultivars with distinct ROL capacities by increasing soil Mn abundance. Results showed that Mn(II) addition to the soil led to more Cr(III) being released into the pore water, and the dissolved Cr(III) was oxidized to Cr(VI) by ROL and biogenic Mn(III/IV) oxides. The concentration of Cr(VI) in soil and pore water increased linearly with the addition of Mn(II) doses. Mn(II) addition promoted the root-to-shoot translocation and grain accumulation of Cr derived mainly from newly generated Cr(VI) in the soil. These results emphasize that rice ROL and MOM promote the oxidative dissolution of Cr(III) at a high level of soil Mn, resulting in more Cr accumulation in rice grains and increasing dietary Cr exposure risks.
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Cromo , Oryza , Contaminantes del Suelo , Cromo/química , Oxidación-Reducción , Óxidos/química , Suelo/química , Contaminantes del Suelo/análisis , Solubilidad , AguaRESUMEN
Background: Although homeostasis of the cardiovascular system is regulated by the cerebral cortex via the autonomic nervous system, the role of abnormal brain functional connectivity (FC) networks in patients with cardiac dysfunction remains unclear. Here, we report thalamus-based FC alterations and their relationship with clinical characteristics in patients with coronary heart disease (CHD). Methods: We employed resting-state functional magnetic resonance imaging (rs-fMRI) to acquire imaging data in twenty-six patients with CHD alongside sixteen healthy controls (HCs). Next, we performed a thalamus-based FC analysis to profile abnormal FC patterns in the whole brain. Subsequently, the mean time series of the brain regions that survived in the FC analysis were used to determine correlations with clinical parameters in patients with CHD. Results: We found no statistically significant differences in demographic and clinical data between patients with CHD and HCs. Patients with CHD showed decreased FC patterns between bilateral thalami and left hemisphere, encompassing supplementary motor area, superior frontal gyrus, superior parietal gyrus, inferior parietal gyrus, middle cingulate cortex, lingual gyrus and calcarine sulcus. Conclusions: These findings not only have implications in clarifying the relationship between cerebral functional imbalance and cardiovascular system, but also provide valuable insights to guide future evaluation and management of cardiac autonomic regulation via the brain-heart axis.
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Cr(VI) from oxidation of geogenic Cr(III) minerals is gradually becoming the primary source of Cr(VI) in soils and groundwater instead of direct emissions. Thermodynamically, natural oxidants of Cr(III) are limited to O2 and Mn oxides. The oxidation of Cr(III) occurs commonly in oxic soils but the difference in the oxidative dissolution of Cr(III) by Mn oxides in different redox soils (especially under anoxic conditions) is not fully understood and field evidence is lacking. Here, the relationship between Cr(VI) and Mn oxides in basalt-origin soil profiles under three different redox conditions (anoxic, suboxic and oxic) was studied. The oxidative dissolution of chromite was validated by synthesising δ-MnO2 that was close to biogenic Mn oxides under anoxic and oxic conditions. In anoxic soils, high levels of Cr(VI) were detected in the same horizons as those where Cr(III)-minerals co-existed with Mn(III/IV) oxides, suggesting an exclusive pathway for Cr(VI) generation through oxidation by Mn oxides where there was a deficiency of other oxidants, such as O2. In oxic soils, the highly abundant Fe oxides combined with Cr(III) to form Cr(III)-Fe(III) oxyhydroxides and Cr(VI) was generated mainly via slow oxidation by O2. The chromite oxidation experiment results also indicated that a high abundance of Mn oxides could promote chromite oxidative dissolution to generate Cr(VI), even under anoxic conditions. Additionally, the form of Cr and the reactivity and abundance of Mn oxides and reducing agents controlled the net content of Cr(VI) in the soil. This study showed that, even under reducing conditions, Cr(III) is readily oxidised by Mn oxides to generate Cr(VI) in reductant-deficient and Mn-rich soils, which may lead to the continuous introduction of Cr(VI) into groundwater and agricultural soils.
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Óxidos , Suelo , Cromo , Compuestos Férricos , Compuestos de Manganeso , Minerales , Oxidantes , Oxidación-ReducciónRESUMEN
Basalt-derived soils are widespread worldwide. Such soils contain high levels of heavy metals like chromium (Cr), which is a serious environmental concern. However, little is known regarding the enrichment and speciation of Cr during the basalt weathering process. Therefore, two basalt-derived soil profiles (Nitisol and Ferralsol) in the Leizhou Peninsula, south tropical China, were investigated to explore the redistribution and transformation of Cr during basalt weathering. All profiles could be divided into three layers: rocks, saprolites, and soils. The Nitisol and Ferralsol profiles exhibited strong (kaolinization) and extreme (laterization) degrees of weathering, respectively. Results showed that Cr concentrations in the saprolites (234 to 315 mg·kg-1) were higher than those in basalt rocks (139 to 159 mg·kg-1), indicating that Cr was enriched with the continuous loss of Si and other mobile macro-elements. While high levels of Cr were also enriched in the soils (178 to 430 mg·kg-1) accompanied with Fe. However, in the upper soils of the Ferralsol profile, the acidity and organic matter could promote the leaching of Cr. Geochemical fractions and EPMA mapping showed that chromite and olivine were the main Cr-bearing minerals in basalt, but Fe-oxides (e.g., goethite and hematite) contained the highest portion of Cr in weathered saprolites and soils. The availability of Cr in the soil was extremely low due to the high stability of Cr bound to Fe-oxides. However, the decreasing contents of Cr bound to Fe-oxides in the upper soils of the Ferralsol profile indicated that Cr could also be released during Fe leaching. In conclusion, the weathering of basalt can lead to the enrichment of Cr in Fe-(hydro)oxides, which are the main controlling minerals for Cr mobility in basalt-derived soils. Further research is needed to evaluate the effect of Fe-(hydro)oxide formation and dissolution on the release of soil Cr.
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Cromo , Contaminantes del Suelo , China , Cromo/análisis , Monitoreo del Ambiente , Silicatos , Suelo/química , Contaminantes del Suelo/análisisRESUMEN
Chromium (Cr) is a toxic heavy metal that is heavily discharged into the soil environment due to its widespread use and mining. High Cr levels may pose toxic hazards to plants, animals and humans, and thus have attracted global attention. Recently, much progress has been made in elucidating the mechanisms of Cr uptake, transport and accumulation in soil-plant systems, aiming to reduce the toxicity and ecological risk of Cr in soil; however, these topics have not been critically reviewed and summarised to date. Accordingly, based on available data-especially from the last five years (2017-2021)-this review traces a plausible link among Cr sources, levels, chemical forms, and phytoavailability in soil; Cr accumulation and translocation in plants; and Cr phytotoxicity and detoxification in plants. Additionally, given the toxicity and hazard posed by Cr(VI) in soils and the application of reductant materials to reduce Cr(VI) to Cr(III) for the remediation of Cr(VI)-contaminated soils, the reduction and immobilisation mechanisms by organic and inorganic reductants are summarised. Finally, some priority research challenges concerning the biogeochemical behaviour of Cr in soil-plant systems are highlighted, as well as the environmental impacts resulting from the application of reductive materials and potential research prospects.
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Restauración y Remediación Ambiental , Contaminantes del Suelo , Cromo/análisis , Cromo/toxicidad , Humanos , Plantas , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidadRESUMEN
To determine the content of extracts in different processed products of Chuanxiong Rhizoma and the content of chlorogenic acid, ferulic acid, senkyunolide â , coniferyl ferulate, senkyunolide A and ligustilide, in order to study the effect of different proces-sing methods on the alcohol-soluble extract and the content of six ingredients of Chuanxiong Rhizoma. The extract was determined according to the alcohol-soluble extract determination method set forth in item 2201 of the 2020 Chinese Pharmacopoeia â £; the content was determined by using Agilent TC-C_(18) column(4.6 mm×250 mm, 5 µm) for gradient elution, with acetonitrile(A)-0.5% acetic acid solution(B) as the mobile phase; the column temperature was at 30 â; the flow rate was 1.0 mL·min~(-1), the detection wavelength was 285 nm; and the injection volume was 10 µL. Compared with Chuanxiong Rhizoma, the extracts of processed products all increased significantly; by the degree of increase, the order was stir-frying Chuanxiong Rhizoma with honey>stir-frying Chuanxiong Rhizoma with rice wine>stir-frying Chuanxiong Rhizoma with Angelicae Dahuricae Radix decoction>stir-frying Chuanxiong Rhizoma with tea decoction; the HPLC method was convenient and reliable, with a high linear relationship of chlorogenic acid, ferulic acid, senkyunolide â , coniferyl ferulate, senkyunolide A and ligustilide, and a high precision, repeatability, stability and the sample recovery rate in Chuanxiong Rhizoma and its processed products. There were 15 chromatographic peaks before and after processing, eight of them were identified. Compared with the pre-processing, two chromatographic peaks were added after the stir-frying with honey and rice wine; and four chromatographic peaks were added after the processing with Angelicae Dahuricae Radix decoction; the contents of chlorogenic acid, ferulic acid, senkyunolide â , coniferyl ferulate, senkyunolide A, and ligustilide in stir-frying Chuanxiong Rhizoma with rice wine were all reduced. Except for the content of ferulic acid that increased, the content of the other five components decreased in stir-frying Chuanxiong Rhizoma with honey, stir-frying Chuanxiong Rhizoma with tea decoction, and stir-frying Chuanxiong Rhizoma with Angelicae Dahuricae Radix decoction. Rice wine, honey, decoction of tea and Angelicae Dahuricae Radix could all promote the dissolution of chemical components in Chuanxiong Rhizoma, and increase the content of extract; the changes in the contents of six components of different processed products could provide a certain basis for studying chemical composition and efficacy of different processed products of Chuanxiong Rhizoma.
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Medicamentos Herbarios Chinos , Vino , Ácido Clorogénico , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/análisis , Rizoma/químicaRESUMEN
Ninety-five wild forage plants (belonging to 22 species of 18 families) and their corresponding rhizosphere soil samples were collected from wastelands of a large-scale abandoned Hg mining region for total Hg (THg) and methylmercury (MeHg) analysis. The forage plant communities on the wastelands were dominated by the Asteraceae, Crassulaceae, and Polygonaceae families. The THg and MeHg concentrations in the forage plants varied widely and were in the range of 0.10 to 13 mg/kg and 0.19 to 23 µg/kg, respectively. Shoots of Aster ageratoides showed the highest average THg concentration of 12 ± 1.1 mg/kg, while those of Aster subulatus had the highest average MeHg concentrations of 7.4 ± 6.1 µg/kg. Both the THg and MeHg concentrations in the aboveground plant parts exhibited positive correlations with the THg (r = 0.70, P < 0.01) and MeHg (r = 0.68, P < 0.01) concentrations in the roots; however, these were not correlated with the THg and MeHg concentrations in their rhizosphere soils. The species A. ageratoides, A. subulatus, and S. brachyotus showed strong accumulation of Hg and are of concern for herbivorous/omnivorous wildlife and feeding livestock. Taking the provisional tolerable weekly intake (PTWI) values for IHg recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA in Summary and conclusions of the seventy-second meeting of the joint FAO/WHO expert committee on food additives Rome, Italy, 2010) for human dietary exposure of 4 ng/g into account, the daily intake of IHg by a 65 kg animal grazing on 1.0 kg of forage (dry weight) would be between 190 and 13,200 µg, three to five orders of magnitude higher than the permitted limit, suggesting a potential risk of exposure.
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Mercurio , Compuestos de Metilmercurio , Animales , Monitoreo del Ambiente , Humanos , Italia , Mercurio/análisis , MineríaRESUMEN
BACKGROUND AND OBJECTIVES: Ablative fractional laser treatment has been used to improve the color and texture of hypertrophic scars with safe and effective results. However, no consensus on the optimal time to initiate fractional laser treatment is available. The effect on early-stage scars remains controversial. This study was designed to assess the efficacy and safety of ablative fractional carbon dioxide (CO2 ) laser treatments for hypertrophic burn scars and to analyze the efficacy and safety in the early period within 3 months after injury. STUDY DESIGN/MATERIALS AND METHODS: We performed a retrospective study of 221 hypertrophic scar patients. According to the time of the first laser treatment after injury, patients were divided into five subgroups, including less than 1 month, 1-3 months, 3-6 months, 6-12 months, and more than 12 months postinjury. One month after the last laser treatment, the scars were assessed by photography, the Vancouver Scar Scale (VSS), durometry, and spectrocolorimetry. RESULTS: The patients included 118 males and 103 females. The average age was 33.6 years. Fire/flame was the primary injury source. Thirty-six percent of the patients underwent at least one fractional CO2 laser treatment. All the included patients, including those treated within 1 month after injury, had significantly decreased VSS scores after laser treatment. We also noted that hardness and redness scores were decreased after treatment for both scars treated within 3 months and those treated more than 12 months after injury. Seepage (17.6%), bleeding (22.2%), and swelling (9.0%) were the main adverse events after laser treatment. CONCLUSIONS: This study demonstrated the safety and efficacy of ablative fractional CO2 laser treatment applied to early-stage burn scars. The optimal time for laser application for burn patients can be within 1 month after injury. Durometry and spectrocolorimetry were effective for assessing scars as objective modalities. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.
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Quemaduras , Cicatriz Hipertrófica , Láseres de Gas , Adulto , Quemaduras/complicaciones , Dióxido de Carbono , Cicatriz , Cicatriz Hipertrófica/etiología , Cicatriz Hipertrófica/patología , Cicatriz Hipertrófica/cirugía , Femenino , Humanos , Láseres de Gas/uso terapéutico , Masculino , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Mercury (Hg) mining activities are an important anthropogenic source of atmospheric Hg. The Xunyang Hg mine located in Shaanxi Province is the largest active Hg producing centre in China. To understand the biogeochemical processes of atmospheric Hg through Hg mining activities, six groups of experimental pots were carefully designed to investigate the effect of Hg mining activities on Hg contamination from atmospheric deposition in the local surface soils. Based on the variations of Hg in the soil from the experimental pots, the deposition flux and loading of Hg in the Xunyang Hg mining district were investigated. The results showed that the average concentration of total gaseous mercury (TGM) as high as 193⯱â¯122â¯ngâ¯m-3 was observed in the ambient air, which was orders of magnitude higher than that in remote areas. The average deposition flux and annual loading of atmospheric Hg were 72â¯mgâ¯m-2 y-1 and 10â¯tâ¯y-1, respectively. The dominant atmospheric Hg deposition is within a distance range of 6.0-12â¯km from the Hg retorting facility, accounting for approximately 85% of the total Hg loading. After 14 months of exposure, total mercury (THg) concentrations in the soil from the experimental pots increased 0.35-9.5 times, and the highest concentrations of methylmercury (MeHg) (3.7⯱â¯2.9⯵gâ¯kg-1) in soil were observed in February. Concentrations as high as 643⯵gâ¯kg-1 THg and 13⯵gâ¯kg-1 MeHg in rice were observed in the second experimental year. Elevated concentrations of both THg and MeHg in rice indicated that the newly deposited atmospheric Hg was bioavailable, readily methylated, and taken up by rice, suggesting that the ongoing Hg mining activities cause serious Hg contamination in the soil-rice ecosystem and posed a threat to local residents in the Xunyang Hg mining area.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Mercurio/análisis , Compuestos de Metilmercurio/análisis , Oryza/química , Contaminantes del Suelo/análisis , Atmósfera/química , China , Ecosistema , Minería , Suelo/químicaRESUMEN
BACKGROUND: Joint contracture is the major clinical complication in burn patients, especially, the severe burn patients. This study aimed to investigate the number and severity of joint contractures in patients with burns affecting greater than or equal to 50% of the total body surface area (TBSA) undergoing early rehabilitation in a burn intensive care unit (BICU). METHODS: We analyzed burn patients with burns affecting greater than or equal to 50% of the TBSA admitted to a BICU who received early rehabilitation within 7 days post-injury from January 2011 to December 2015. Demographic and medical information was collected. The range of motion (ROM) of different joints was measured 1 month post-admission. Spearman's correlation coefficient and logistic regression analysis was used to determine predictors of the presence and severity of contractures. RESULT: The average affected TBSA of the included burn patients was 67.4%, and the average length of stay in the BICU was 46.2 ± 28.8 days. One hundred and one of 108 burn patients (93.5%) developed at least one joint contracture. The ROM in 67.9% of the affected joints was mildly limited. The majority of contractures in severe burn patients were mild (37.7%) or moderate (33.2%). The wrist was the most commonly affected joint (18.2%), followed by the shoulder, ankle, hip, knee, and elbow. A predictor of the presence of contractures was the length of hospital stay (p = 0.049). The severe contracture was related to the area of full-thickness burns, the strict bed rest time, and the duration of rehabilitation in BICU. The length of rehabilitation stay (days) in patients with moderate contracture is 54.5% longer than that in severe contracture (p = 0.024). CONCLUSION: During the long stay in BICU, the length of rehabilitation stay in a BICU could decrease the severity of contractures from severe to moderate in the patients with equal to 50% of the TBSA. Hence, this research reveals the important role of early rehabilitation interventions in severe burn patients.
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PURPOSE: Ovarian hyperstimulation syndrome (OHSS) is a serious complication of assisted reproductive technology (ART) treatment. However, there are limited data regarding the ability of the luteal GnRH antagonist cetrorelix to reduce the incidence of moderate and severe OHSS, and the mechanism remains unclear. Thus, we designed a study to assess the effectiveness of cetrorelix to prevent early moderate and severe OHSS in high-risk patients undergoing controlled ovarian stimulation for IVF/ICSI. METHODS: In this prospective cohort study, 105 patients with high-risk OHSS undergoing cryopreservation of all embryos were divided into two groups according to their personal choice. The cetrorelix group (n = 65) received 0.25 mg of cetrorelix by subcutaneous injection daily, from days 3 to 5 post-oocyte retrieval (POR); the control group (n = 40) received no drug. The primary outcome measures were the incidence and severity of early moderate and severe OHSS. Secondary measures included serum estradiol levels, ovarian volume, ascites volume, hematocrit values, and WBC count on days 3, 6, and 9 POR. VEGF and EGR-1 levels were assessed, and binary logistic regression analysis was applied to predict associations between clinical variables and OHSS. RESULTS: Ninety-six patients were examined. The incidence of moderate and severe OHSS was significantly lower in the cetrorelix group than in the control group (18.03% and 37.14%, respectively; P = 0.037). Serum estradiol (P = 0.013), white blood cell count (P = 0.031), ascites volume (P = 0.036), EGR-1 (P = 0.025), and VEGF levels (P = 0.015) were significantly higher in the control group on day 6 POR than on day 3 POR, while no increase was observed between day 3 POR and day 6 POR in the cetrorelix group, indicating a faster regression of OHSS symptoms. Cetrorelix intervention was associated with the incidence and severity of OHSS (OR 0.29, 95% CI 0.11-0.78, P = 0.014). CONCLUSION: Cetrorelix effectively reduces the incidence of early moderate and severe OHSS in high-risk women and decreases serum VEGF levels.
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Fertilización In Vitro/efectos adversos , Fertilización In Vitro/métodos , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Hormona Liberadora de Gonadotropina/uso terapéutico , Síndrome de Hiperestimulación Ovárica/tratamiento farmacológico , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Embarazo , Estudios ProspectivosRESUMEN
OBJECTIVE: This study aims to clarify whether the effect of intralesional triamcinolone acetonide injection during the early stage of scarring differs from the static stage, which still remains unclear. METHODS: A total of 108 patients with pathological scars were enrolled in this study and were divided into 2 groups according to the time of first treatment after injury: the early stage group(≤6 months after injury) and the static stage group(>6 months after injury). Patients of both groups were then treated with intralesional triamcinolone acetonide injection. The Vancouver scar scale was adopted for the evaluation of scars, and a durometer was utilized for the measurement of the hardness of the scar. The visual analog scale was adopted for the assessment of patients' subjective feelings (pruritus and pain). In the meantime, adverse drug reactions were also recorded. RESULTS: After intralesional injection of triamcinolone acetonide, most of the hypertrophic scars and keloids improved in color, thickness, softness, and vascular distribution. The hardness of scars improved significantly. The overall efficacy of the static stage group was superior to the early stage group. Most patients, after the injection of triamcinolone acetonide, had significant alleviation or even total loss of cicatricial pain and pruritus. CONCLUSIONS: This study demonstrates that the treatment efficacy was better when applied during the static stage of pathological scarring rather than the early stage, which might be due to macrophages and their released cytokines. This study provides new clinical evidence for optimizing drug therapy of pathological scars.
Asunto(s)
Cicatriz Hipertrófica/tratamiento farmacológico , Glucocorticoides/administración & dosificación , Queloide/tratamiento farmacológico , Triamcinolona Acetonida/administración & dosificación , Adolescente , Adulto , Anciano , Niño , Preescolar , Cicatriz Hipertrófica/complicaciones , Femenino , Glucocorticoides/efectos adversos , Humanos , Inyecciones Intralesiones/efectos adversos , Queloide/complicaciones , Masculino , Persona de Mediana Edad , Dolor/diagnóstico , Dolor/tratamiento farmacológico , Dolor/etiología , Dimensión del Dolor , Prurito/diagnóstico , Prurito/tratamiento farmacológico , Prurito/etiología , Índice de Severidad de la Enfermedad , Factores de Tiempo , Tiempo de Tratamiento , Resultado del Tratamiento , Triamcinolona Acetonida/efectos adversos , Adulto JovenRESUMEN
Mercury-antimony (HgSb) mining activities are important anthropogenic sources of Hg and Sb to the local environment. The Xunyang HgSb mine situated in Shaanxi Province is an active Hg mine in China. To understand the emission, transportation, and deposition of Sb through HgSb mining activities, current study systematically monitored the Sb concentration in precipitation in the Xunyang HgSb mining district. Five groups of experimental pots were carefully designed to further investigate the influence of HgSb mining activities on the Sb contamination in the local surface soil. Based on the overtime increasing of the Sb concentrations in soil from experimental pots, for the first trial, we estimated the atmospheric deposition flux/mass of Sb in the Xunyang HgSb mining district. Our results showed that the concentrations of Sb in precipitation in the Xunyang HgSb mining district ranged from 0.71⯵gâ¯L-1 to 19⯵gâ¯L-1 (meanâ¯=â¯4.2⯱â¯4.5⯵gâ¯L-1), which was orders of magnitude higher than that at the control site. As expected, the concentration of Sb in precipitation was highly elevated near of the HgSb smelter and gradually decreased with distance from the smelter. After 12 months exposure, Sb concentrations in soil of experimental pots were increased by 1.2-8.5 times. The average atmospheric wet and dry deposition flux of Sb in the Xunyang HgSb mining district were 7.2⯱â¯6.9⯵gâ¯m-2 day-1 and 2.1⯱â¯4.7â¯mgâ¯m-2 day-1, respectively; the annual wet and dry deposition mass of Sb through HgSb mining activities were estimated to be 1.6â¯tâ¯y-1 and 158â¯tâ¯y-1, respectively, indicating that dry deposition was the dominant pathway (98⯱â¯1.2%) for the removal of Sb from the atmosphere. Our results confirmed that the ongoing HgSb mining activities resulted to serious Sb contamination to terrestrial ecosystems, posing a potential threat to local residents in the Xunyang HgSb mining district.
Asunto(s)
Antimonio/análisis , Atmósfera/química , Minería , Contaminantes del Suelo/análisis , Suelo/química , China , Monitoreo del Ambiente , Mercurio/análisis , Lluvia/químicaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: In traditional Chinese medicine, the aerial parts of Aeschynomene indica L. (AIL) have been used for wound healing, and to treat urinary tract infection, hepatitis, enteritis, dysentery, nyctalopia, conjunctivitis, urticaria, and furuncle. However, no scientific investigation has been conducted on its wound healing potential. AIM OF THE STUDY: To investigate the effects of AIL extract on wound healing, isolate the active constituent and reveal the possible mechanism of enhancing wound healing. MATERIALS AND METHODS: The circular excision wound healing model was used to evaluate in vivo wound-healing activity. Hematoxylin and eosin staining was applied to assess inflammatory cells infiltration, angiogenesis, fibroblast proliferation, collagen synthesis, collagen remodeling, and skin appendages generation. Sirius red-picric acid staining was employed for quantitative analysis of the ratio of collagen I/III. Immunohistochemical staining for CD68, CCR7 (CD197), CD163, TGF-ß1 and α-SMA was performed to determine macrophages phenotypes transition (M1-to-M2) and prove the scar-improving effect of AIL on wound healing. RESULTS: We successfully isolated the active constituent (Sub-Fr0.2) for wound healing from AIL extract, circular excision wound healing experiment and hematoxylin & eosin staining showed Sub-Fr0.2 has a significant promoting effect on wound healing. Results of sirius red-picric acid staining demonstrated a reduced ratio of collagen I/III in the Sub-Fr0.2 group as compared with the vehicle group. Immunohistochemical staining for CD68, CCR7 (CD197), and CD163 in the Sub-Fr0.2 group exhibited an elevated speed of macrophages transiting from M1 phenotype to M2 phenotype, when compared with the vehicle group. Besides, the expression of TGF-ß1 and α-SMA were inhibited on wounds treated with the ointment containing Sub-Fr0.2. CONCLUSION: Leaves of AIL and its active constituent (Sub-Fr0.2) effectively promoted wound healing and reduced scar formation, this efficacy might be exerted by accelerating macrophages phenotypes transition and inhibiting TGF-ß1 and α-SMA expression.