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1.
Mol Biol Evol ; 41(4)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38507661

RESUMEN

Recent studies have suggested that dogs were domesticated during the Last Glacial Maximum (LGM) in Siberia, which contrasts with previous proposed domestication centers (e.g. Europe, the Middle East, and East Asia). Ancient DNA provides a powerful resource for the study of mammalian evolution and has been widely used to understand the genetic history of domestic animals. To understand the maternal genetic history of East Asian dogs, we have made a complete mitogenome dataset of 120 East Asian canids from 38 archaeological sites, including 102 newly sequenced from 12.9 to 1 ka BP (1,000 years before present). The majority (112/119, 94.12%) belonged to haplogroup A, and half of these (55/112, 49.11%) belonged to sub-haplogroup A1b. Most existing mitochondrial haplogroups were present in ancient East Asian dogs. However, mitochondrial lineages in ancient northern dogs (northeastern Eurasia and northern East Asia) were deeper and older than those in southern East Asian dogs. Results suggests that East Asian dogs originated from northeastern Eurasian populations after the LGM, dispersing in two possible directions after domestication. Western Eurasian (Europe and the Middle East) dog maternal ancestries genetically influenced East Asian dogs from approximately 4 ka BP, dramatically increasing after 3 ka BP, and afterwards largely replaced most primary maternal lineages in northern East Asia. Additionally, at least three major mitogenome sub-haplogroups of haplogroup A (A1a, A1b, and A3) reveal at least two major dispersal waves onto the Qinghai-Tibet Plateau in ancient times, indicating eastern (A1b and A3) and western (A1a) Eurasian origins.


Asunto(s)
Genoma Mitocondrial , Animales , Perros , Animales Domésticos/genética , Asia Oriental , ADN Mitocondrial/genética , Variación Genética , Haplotipos , Mamíferos/genética , Filogenia
2.
Artículo en Inglés | MEDLINE | ID: mdl-38290457

RESUMEN

Objective: Exploring the clinical efficacy of neomycin and sakubactria valsartan in the treatment of patients with chronic heart failure (CHF) and atrial fibrillation. This study investigates the potential benefits of combining neomycin with sakubactria valsartan, a medication with a background of demonstrated efficacy in cardiovascular conditions, to address the complex challenges presented by chronic heart failure and atrial fibrillation. Methods: Using a single-center clinical randomized trial, 111 patients with CHF complicated with atrial fibrillation who were treated in the cardiovascular department of Xingtai Third Hospital from June 2019 to March 2021 were randomly divided into two groups. In the control group, 56 patients received treatment with Western Medicine Foundation + Shakubatra valsartan. In the experimental group, consisting of 55 patients, the treatment was identical to the control group, with the additional administration of neomycin.. After 12 weeks of continuous treatment, the echocardiograms, electrocardiogram parameters, and Differences in changes in serum soluble growth stimulating gene 2 protein (sST2) and galactose agglutinin 3 (Gal-3), clinical efficacy, and incidence of adverse reactions. Results: Before treatment, no significant differences existed in LVEF, LVEDV, FS, and SV between the experimental and control groups (P > .05). Post-treatment, both groups exhibited significant improvements in these parameters, with the experimental group showing statistically higher values (P < .05).Similarly, pre-treatment comparisons of Pd, sST2, Gal-3, and NT-proBNP revealed no significant differences between the groups (P > .05). After treatment, both groups showed significant reductions, with the experimental group demonstrating lower values (P < .05).Clinical efficacy assessment post-treatment showed significant differences. The experimental group had a basic cure rate of 45.45%, a significant effective rate of 43.64%, and an effective rate of 10.91%, while the control group had rates of 28.57%, 48.21%, and 23.21%, respectively (P < .05).Adverse reactions occurred in 9 and 4 patients in the experimental and control groups, respectively. The severity was not significant, and treatment was uninterrupted (P > 0.05).The treatment improved heart function and reduced atrial fibrillation occurrences, holding clinical significance by potentially enhancing patients' quality of life and decreasing cardiovascular events. These results highlight the clinical significance of this treatment, which may help improve patients' quality of life and reduce the occurrence of cardiovascular events. Conclusion: The treatment of patients with CHF combined with atrial fibrillation using neomycin and sakubactria valsartan can more effectively improve their cardiac function and alleviate the condition of atrial fibrillation, which is worthy of clinical promotion and application. In actual clinical practice, physicians and healthcare providers may consider incorporating this treatment into their treatment regimens, especially for patients who need to improve heart function and reduce the risk of atrial fibrillation. Additionally, further research and clinical trials can further validate these findings to ensure their effectiveness and safety. These insights will help the medical community better understand how to apply this treatment to real patients and maximize its clinical effectiveness.

3.
J Fish Dis ; 45(3): 451-459, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34962648

RESUMEN

Outbreaks of viral encephalopathy and retinopathy (VER) in marine and freshwater species severely devastate the aquaculture worldwide. The causative agent of VER is nervous necrosis virus (NNV), which mainly infects the early developmental stages of fish, limiting the effectiveness of vaccines. To counter this case, the anti-NNV potentials of nine drugs with broad-spectrum antiviral activity were explored using ribavirin as a positive drug. Toxicity of the selected drugs to SSN-1 cells and grouper was firstly evaluated to determine the safety concentrations. For screening in vitro, amantadine and oseltamivir phosphate can relieve the cytopathic effects and inhibit NNV replication with the 90% inhibitory concentrations (IC90 ) of 38.74 and 106.75 mg/L, respectively. Amantadine has a stronger anti-NNV activity than ribavirin at the with- and post-NNV infection stages, indicating that it is a potential therapeutic agent against VER by acting directly on NNV. Similarly, amantadine also has a strong anti-NNV activity in vivo with the IC90 of 27.91 mg/L at the 7 days post-infection, while that was 73.25 mg/L for ribavirin. Following exposure to amantadine (40 mg/L) and ribavirin (100 mg/L) for 7 days, the survival rates of NNV-infected grouper were increased to 44% and 39%, respectively. The maximum amantadine content (11.88 mg/Kg) in grouper brain was reached following exposure for 24 hr, and amantadine can be quickly excreted from fish, reducing the risk of drug residue. Results so far indicated that amantadine is a promising therapeutic agent against NNV in aquaculture, providing an effective strategy for VER control at the early developmental stages of fish.


Asunto(s)
Encefalopatías , Enfermedades de los Peces , Nodaviridae , Infecciones por Virus ARN , Enfermedades de la Retina , Amantadina/farmacología , Amantadina/uso terapéutico , Animales , Enfermedades de los Peces/tratamiento farmacológico , Enfermedades de la Retina/tratamiento farmacológico , Enfermedades de la Retina/veterinaria
4.
Nanotechnology ; 33(7)2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34740207

RESUMEN

For the electrochemcial hydrogen production, the oxygen evolution reaction (OER) is a pivotal half-reaction in water splitting. However, OER suffers sluggish kinetics and high overpotential, leading to the increase of overall energy consumption and decrease of the energy efficiency. In this work, high-quality cobalt oxide porous nanotubes (Co3O4-PNTs) are easily obtained by simple self-template approach. One-dimensional (1D) porous structure provides the large specific surface area, enough abundant active atoms and effective mass transfer. In addition, Co3O4-PNTs also own self-stability of 1D architecture, benefitting the their durability for electrocatalytic reaction. Thus, Co3O4-PNTs with optimal annealing temperature and time reveal the attractive alkaline OER performance (Tafel slope of 56 mV dec-1and 323 mV overpotential at 10 mA cm-2), which outperform the Co3O4nanoparticles and benchmark commercial RuO2nanoparticles. Furthermore, Co3O4-PNTs also exhibit excellent OER durability for least 10 h at the 10 mA cm-2. Overall, Co3O4-PNTs with low cost can be serve as a highly reactive and economical catalyst for OER.

5.
Ecotoxicol Environ Saf ; 228: 113037, 2021 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-34856484

RESUMEN

Over the past few decades, nonferrous mining has produced numerous waste rock and part of the waste that has not been properly treated was generally dumped at roadsides and hill slopes. However, the vertical distributions of toxic metal(loid)s and composition of microbial communities in waste heap and the under-laid pristine soil are rarely studied. In this work, the fraction-related distributions of toxic metal(loid)s were investigated at a waste heap profile and the indigenous microbial assemblages were also analyzed by Illumina sequencing of 16 s rRNA genes. Results showed that compared to the under-laid pristine soil, content of toxic metal(loid)s, especially Cd, As and Pb, in waste rock layer were higher. Most of As in subsoil existed as non-specifically sorbed and specifically-sorbed fractions, which could be ascribed to the migration from the upper layer. The mobility was significantly correlated with Eh, EC, clay content, CEC and the total content of metal(loid)s. Phyla Proteobacteria, Acidobacteria and Firmicutes dominated the microbial communities. The microbial community compositions at the genus level were similar, but their relative abundances were mainly influenced by pH, CEC, Eh, SOM, and bioavailability content of toxic metal(loid)s. Besides, microbial functions of elements (S, Fe, Mn and As) oxidation/reduction and metabolites (siderophore, biosurfactant, organic acid, phosphatase and urease) potentially were used for pollutants bioremediation.

6.
Ecotoxicol Environ Saf ; 191: 110009, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31806252

RESUMEN

In recent years, many studies have been devoted to investigate the application of microbial induced phosphate precipitation (MIPP) process for potentially toxic element polluted soil remediation. MIPP biomineralization technique exhibits a great potential to efficiently remediate polluted soil considering its low cost, green and ecofriendly process, and simple in operation. This paper represented a review on the state of the art of polluted soil remediation based on MIPP technique. Briefly, certain defined criteria on targeted microbe selection was discussed; an overall review on the utilization of MIPP process for toxic ions biomineralization in soil was provided; influencing factors reported in the literature, such as pH, temperature, humic substances, coexisting ions, effective microbial population, and enzyme activity, were then comprehensively reviewed; finally; a special emphasis was given to enhance MIPP remediation performance in soil in future research.


Asunto(s)
Microbiología del Suelo , Contaminantes del Suelo/química , Biomineralización , Precipitación Química , Restauración y Remediación Ambiental , Iones , Fosfatos/química , Suelo/química , Contaminantes del Suelo/metabolismo
7.
BMC Genomics ; 20(1): 438, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31146680

RESUMEN

BACKGROUND: Habitats colonized by acidophiles as an ideal physical barrier may induce genetic exchange of microbial members within the common communities, but little is known about how species in extremely acidic environments diverge and evolve. RESULTS: Using the acidophilic sulfur-oxidizer Acidithiobacillus as a case study, taxonomic reclassifications of many isolates provides novel insights into their phylogenetic lineage. Whole-genome-based comparisons were attempted to investigate the intra- and inter-species divergence. Recent studies clarified that functional and structural specificities of bacterial strains might provide opportunities for adaptive evolution responding to local environmental conditions. Acidophilic microorganisms play a key role in the acidification of natural waters and thus the formation of extremely acidic environments, and the feedbacks of the latter might confer the distinct evolutionary patterns of Acidithiobacillus spp. Varied horizontal gene transfer events occurred in different bacterial strains, probably resulting in the expansion of Acidithiobacillus genomes. Gene loss as another evolutionary force might cause the adaptive phenotypic diversity. A conceptual model for potential community-dependent evolutionary adaptation was thus proposed to illustrate the observed genome differentiation. CONCLUSIONS: Collectively, the findings shed light on the phylogeny and divergent evolution of Acidithiobacillus strains, and provided a useful reference for evolutionary studies of other extremophiles.


Asunto(s)
Acidithiobacillus/clasificación , Acidithiobacillus/genética , Evolución Molecular , Genoma Bacteriano , Acidithiobacillus/metabolismo , Genes Bacterianos , Especiación Genética , Tamaño del Genoma , Secuencias Repetitivas Esparcidas , Oxidación-Reducción , Filogenia , Azufre/metabolismo
8.
Pharmacol Res ; 149: 104459, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31541689

RESUMEN

Gut microbiota and their metabolites (short-chain fatty acids, SCFAs) are associated with the pathogenesis of rheumatoid arthritis (RA). Total Clematis triterpenoid saponins (CTSs) prepared from Clematis mandshurica Rupr. possess therapeutic benefits for arthritic diseases. However, the poor pharmacokinetic properties of CTSs have obstructed the translation of these natural agents to drugs. Here, we examined the effects of CTSs on arthritis symptoms, gut microbiota and SCFAs in rats with collagen-induced arthritis (CIA). Our results showed that the arthritis index scores of CIA rats treated with CTSs were significantly lower than those of the model group. Most importantly, CTSs moderated gut microbial dysbiosis and significantly downregulated the total SCFA concentration in CIA rats. Compared to the control group, CTSs treatment have no significant side effects on the gut microbiota and SCFA metabolism in normal rats. Two differential analyses (LEfSe and DESeq2) were combined to study the details of the changes in gut microbiome, and twenty-four marker taxa at the genus level were identified via a comparison among control, model and CIA rats treated with high doses of CTSs. In particular, the mostly significantly increased gram-negative (G-) and decreased gram-positive (G+) genera in CIA rats were well restored by CTSs. The observed SCFA concentrations demonstrated that CTSs tend to maintain the balance of the gut microbiota. The data presented herein suggest that CTSs could ameliorate arthritis-associated gut microbial dysbiosis and may be potential adjuvant drugs that could provide relief from the gastrointestinal damage caused as a side effect of commonly used drugs.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Clematis/química , Disbiosis/prevención & control , Ácidos Grasos Volátiles/metabolismo , Microbioma Gastrointestinal/efectos de los fármacos , Saponinas/uso terapéutico , Triterpenos/uso terapéutico , Animales , Artritis Experimental/microbiología , Disbiosis/microbiología , Femenino , Ratas , Ratas Wistar , Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificación
9.
Curr Microbiol ; 75(7): 818-826, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29464360

RESUMEN

Iron-oxidizing Acidithiobacillus spp. are applied worldwide in biomining industry to extract metals from sulfide minerals. They derive energy for survival through Fe2+ oxidation and generate Fe3+ for the dissolution of sulfide minerals. However, molecular mechanisms of their iron oxidation still remain elusive. A novel two-cytochrome-encoding gene cluster (named tce gene cluster) encoding a high-molecular-weight cytochrome c (AFE_1428) and a c4-type cytochrome c552 (AFE_1429) in A. ferrooxidans ATCC 23270 was first identified in this study. Bioinformatic analysis together with transcriptional study showed that AFE_1428 and AFE_1429 were the corresponding paralog of Cyc2 (AFE_3153) and Cyc1 (AFE_3152) which were encoded by the extensively studied rus operon and had been proven involving in ferrous iron oxidation. Both AFE_1428 and AFE_1429 contained signal peptide and the classic heme-binding motif(s) as their corresponding paralog. The modeled structure of AFE_1429 showed high resemblance to Cyc1. AFE_1428 and AFE_1429 were preferentially transcribed as their corresponding paralogs in the presence of ferrous iron as sole energy source as compared with sulfur. The tce gene cluster is highly conserved in the genomes of four phylogenetic-related A. ferrooxidans strains that were originally isolated from different sites separated with huge geographical distance, which further implies the importance of this gene cluster. Collectively, AFE_1428 and AFE_1429 involve in Fe2+ oxidation like their corresponding paralog by integrating with the metalloproteins encoded by rus operon. This study provides novel insights into the Fe2+ oxidation mechanism in Fe2+-oxidizing A. ferrooxidans ssp.


Asunto(s)
Acidithiobacillus/metabolismo , Proteínas Bacterianas/genética , Compuestos Ferrosos/metabolismo , Familia de Multigenes , Acidithiobacillus/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/metabolismo , Citocromos c/metabolismo , Regulación Bacteriana de la Expresión Génica , Datos de Secuencia Molecular , Operón , Oxidación-Reducción , Filogenia , Alineación de Secuencia , Azufre/metabolismo
10.
Appl Environ Microbiol ; 83(7)2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28115381

RESUMEN

Recent phylogenomic analysis has suggested that three strains isolated from different copper mine tailings around the world were taxonomically affiliated with Sulfobacillusthermosulfidooxidans Here, we present a detailed investigation of their genomic features, particularly with respect to metabolic potentials and stress tolerance mechanisms. Comprehensive analysis of the Sulfobacillus genomes identified a core set of essential genes with specialized biological functions in the survival of acidophiles in their habitats, despite differences in their metabolic pathways. The Sulfobacillus strains also showed evidence for stress management, thereby enabling them to efficiently respond to harsh environments. Further analysis of metabolic profiles provided novel insights into the presence of genomic streamlining, highlighting the importance of gene loss as a main mechanism that potentially contributes to cellular economization. Another important evolutionary force, especially in larger genomes, is gene acquisition via horizontal gene transfer (HGT), which might play a crucial role in the recruitment of novel functionalities. Also, a successful integration of genes acquired from archaeal donors appears to be an effective way of enhancing the adaptive capacity to cope with environmental changes. Taken together, the findings of this study significantly expand the spectrum of HGT and genome reduction in shaping the evolutionary history of Sulfobacillus strains.IMPORTANCE Horizontal gene transfer (HGT) and gene loss are recognized as major driving forces that contribute to the adaptive evolution of microbial genomes, although their relative importance remains elusive. The findings of this study suggest that highly frequent gene turnovers within microorganisms via HGT were necessary to incur additional novel functionalities to increase the capacity of acidophiles to adapt to changing environments. Evidence also reveals a fascinating phenomenon of potential cross-kingdom HGT. Furthermore, genome streamlining may be a critical force in driving the evolution of microbial genomes. Taken together, this study provides insights into the importance of both HGT and gene loss in the evolution and diversification of bacterial genomes.


Asunto(s)
Clostridiales/genética , Evolución Molecular , Eliminación de Gen , Transferencia de Gen Horizontal , Variación Genética , Biología Computacional , Genoma Bacteriano , Genómica , Redes y Vías Metabólicas , Modelos Genéticos , Filogenia , Estrés Fisiológico
11.
Int J Mol Sci ; 17(9)2016 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-27563887

RESUMEN

In the monitoring of pollutants in an aquatic environment, it is important to preserve water quality safety. Among the available analysis methods, the microbial fuel cell (MFC) sensor has recently been used as a sustainable and on-line electrochemical microbial biosensor for biochemical oxygen demand (BOD) and toxicity, respectively. However, the effect of the background organic matter concentration on toxicity monitoring when using an MFC sensor is not clear and there is no effective strategy available to avoid the signal interference by the combined shock of BOD and toxicity. Thus, the signal interference by the combined shock of BOD and toxicity was systematically studied in this experiment. The background organic matter concentration was optimized in this study and it should be fixed at a high level of oversaturation for maximizing the signal output when the current change (ΔI) is selected to correlate with the concentration of a toxic agent. When the inhibition ratio (IR) is selected, on the other hand, it should be fixed as low as possible near the detection limit for maximizing the signal output. At least two MFC sensors operated with high and low organic matter concentrations and a response chart generated from pre-experiment data were both required to make qualitative distinctions of the four types of combined shock caused by a sudden change in BOD and toxicity.


Asunto(s)
Fuentes de Energía Bioeléctrica , Técnicas Biosensibles/métodos , Monitoreo del Ambiente/métodos , Análisis de la Demanda Biológica de Oxígeno , Aguas Residuales/análisis
12.
Front Psychol ; 15: 1370870, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38840734

RESUMEN

Introduction: As the COVID-19 pandemic raged, controversies about governmental responses to the epidemic also emerged in China. Previous studies mainly described the phenomenon of individual differences on support for governmental responses to COVID-19 with less attention to the underlying causal mechanisms. Thus, this study tries to verify the factors influencing public support for official behaviors in COVID-19. Method: A questionnaire survey was drew on in Wuhan city during the COVID-19 outbreak. The quota sampling method was adopted according to the gender and age structure of the population in Wuhan as well as the educational structure of the urban population in China. Results: Through structural equation analysis, this study confirms that personal factors (namely conscientiousness and nationalistic ideology), behavioral factors (namely media diversity and echo chamber acts) exert significantly positive impacts on support for governmental responses. The echo chamber acts play important mediating roles in the relationship between each independent variable and support for governmental responses. Discussion: The originality of this study is that it constructs a comprehensive model of influencing factors of support for governmental responses with the personal, behavioral, and environmental factors. While contributing insight to political attitude in China, the research results also have significance for promoting public trust and constructing healthy public opinion in China.

13.
IEEE Trans Image Process ; 33: 2639-2651, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38551827

RESUMEN

Current semi-supervised video object segmentation (VOS) methods often employ the entire features of one frame to predict object masks and update memory. This introduces significant redundant computations. To reduce redundancy, we introduce a Region Aware Video Object Segmentation (RAVOS) approach, which predicts regions of interest (ROIs) for efficient object segmentation and memory storage. RAVOS includes a fast object motion tracker to predict object ROIs in the next frame. For efficient segmentation, object features are extracted based on the ROIs, and an object decoder is designed for object-level segmentation. For efficient memory storage, we propose motion path memory to filter out redundant context by memorizing the features within the motion path of objects. In addition to RAVOS, we also propose a large-scale occluded VOS dataset, dubbed OVOS, to benchmark the performance of VOS models under occlusions. Evaluation on DAVIS and YouTube-VOS benchmarks and our new OVOS dataset show that our method achieves state-of-the-art performance with significantly faster inference time, e.g., 86.1 J & F at 42 FPS on DAVIS and 84.4 J & F at 23 FPS on YouTube-VOS. Project page: ravos.netlify.app.

14.
J Med Biochem ; 43(2): 193-199, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38699691

RESUMEN

Background: To explore the correlation between serum uric acid (SUA) and prognosis in patients with chronic heart failure (CHF) after revascularization. Methods: A total of 126 patients with CHF undergoing revascularization [coronary artery intervention (PCI) or coronary artery bypass grafting (CABG)] in the hospital were enrolled as CHF group between December 2021 and October 2022, while 126 healthy controls during the same period were enrolled as healthy control group. The levels of SUA, inflammatory factors and cardiac function in the two groups were detected. The correlation between SUA level and inflammatory factors, cardiac function levels was analyzed. All patients in CHF group were followed up for 6 months to observe prognosis. The differences in the above indexes among patients with different prognosis were compared. The risk factors of prognosis were analyzed by multivariate Logistic regression analysis, and their predictive value for prognosis was evaluated by ROC curves analysis.

15.
Opt Lett ; 38(22): 4644-7, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24322095

RESUMEN

We have demonstrated the realization of a random polymer fiber laser (RPFL) based on laser dye Pyrromethene 597-doped one-dimensional disordered polymer optical fiber (POF). The stabilized coherent laser action for the disordered POF has been obtained by the weak optical multiple scattering of the polyhedral oligomeric silsesquioxanes nanoparticles in the core of the POF in situ formed during polymerization, which was enhanced by the waveguide confinement effect. Meanwhile, the threshold of our RPFL system is almost one order of magnitude lower than that of the liquid core random fiber laser reported previously, which promotes the development of random lasers.

16.
Toxics ; 11(11)2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37999595

RESUMEN

At present, the pollution of arsenic (As) and lead (Pb) is becoming increasingly serious. The pollution caused by the release of As and Pb from lead-zinc mines has seriously affected the water and soil environment and threatened human health. It is necessary to reveal the release characteristics of As and Pb. The actual scene of mine drainage (MD) and rainwater (RW) leaching waste rocks is the one of the main reasons for the release of As and Pb. However, the leaching behavior of As and Pb in these waste rocks under MD and RW suffered from a lack of in-depth research. In this study, we investigated the occurrence of As and Pb in waste rocks (S1-S6) by using X-ray diffraction (XRD) and time-of-flight secondary ion mass spectrometry (TOF-SIMS), and then, the changes in As and Pb concentration and the hydrochemical parameter in leaching solution were systematically studied. Furthermore, the correlation between the release of As and Pb and mineral composition was also evaluated. Results showed that these waste rocks were mainly composed of carbonate and sulfide minerals. As and Pb were mainly bounded or associated with sulfide minerals such as arsenopyrite, pyrite, chalcopyrite, and galena in these waste rocks, and small parts of As and Pb were absorbed or encased by clay minerals such as kaolinite and chlorite. Under MD and RW leaching, the pH, redox potential (Eh), and electric conductivity (EC) of each waste rock tended to be consistent due to their buffering ability; the leachate pH of waste rocks with more carbonate minerals was higher than that of sulfide minerals. Both As and Pb were released most under MD leaching in comparison to RW, reaching 6.57 and 60.32 mg/kg, respectively, due to MD's low pH and high Eh value. However, As in waste rock released more under alkaline conditions because part of the arsenic was in the form of arsenate. As and Pb release were mainly positively correlated with the proportions of sulfide minerals in these waste rocks. MD leaching significantly promoted the release of As and Pb from waste rocks, which would cause a great threat to the surrounding environment, and control measures were imperative. This paper not only reveals the As and Pb pollution mechanism around the lead-zinc mining area but also provides a theoretical basis for the prevention and control of As and Pb pollution in the future.

17.
Phys Rev Lett ; 109(25): 253901, 2012 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-23368465

RESUMEN

We demonstrate the realization of a coherent random fiber laser (RFL) in the extremely weakly scattering regime, which contains a dispersive solution of polyhedral oligomeric silsesquioxanes nanoparticles (NPs) and laser dye pyrromethene 597 in carbon disulfide that was injected into a hollow optical fiber. Multiple scattering of polyhedral oligomeric silsesquioxanes NPs greatly enhanced by the waveguide confinement effect was experimentally verified to account for coherent lasing observed in our RFL system. This Letter extends the NPs-based RFLs from the incoherent regime to the coherent regime.

18.
Zhongguo Zhong Yao Za Zhi ; 37(11): 1659-62, 2012 Jun.
Artículo en Zh | MEDLINE | ID: mdl-22994003

RESUMEN

OBJECTIVE: To study the effect of Salvia miltiorrhiza on alveolar bone metabolism and variation in bone mass in diabetic rats, in order to detect whether it has an inhibitory effect on alveolar bone osteoporosis caused by diabetics. METHOD: Intraperitoneal injection of alloxan induced diabetes in rats. After one week of observation and maintenance of stable blood sugar level, they were treated with S. miltiorrhiza. The rats were sacrificed at the eighth week after fasting for 12 h and blood samples were collected for analysis of blood glucose and rate of bone metabolism. Meanwhile, their alveolar bones were collected for determining bone mineral density (BMD) and histological sections were made for histomorphology observation. RESULT: Diabetic rats showed varying degrees of abnormality in bone metabolism indicators and significant reduction in bone mineral density. After treatment with S. miltiorrhiza, their symptoms reduced to some extend and all indicators were improved especially bone density. CONCLUSION: S. miltiorrhiza has a certain inhibitory effect on alveolar bone osteoporosis in diabetic rats in early stage.


Asunto(s)
Diabetes Mellitus/metabolismo , Medicamentos Herbarios Chinos/farmacología , Maxilar/efectos de los fármacos , Maxilar/metabolismo , Salvia miltiorrhiza/química , Animales , Densidad Ósea/efectos de los fármacos , Diabetes Mellitus/patología , Diabetes Mellitus/fisiopatología , Masculino , Maxilar/patología , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Wistar
19.
Appl Biochem Biotechnol ; 194(9): 3860-3870, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35556208

RESUMEN

Osteoporosis is a general bone-related ailment characterized by reduced bone density and quality, elevated bone fragility, and fractures. It was reported that both aged men and women has an increased risks of osteoporosis. The current research work focused to unveil the beneficial roles of ponicidin treatment in the proliferation and calcium deposition on the osteoblast-like MG-63 cells. The effect of 5 and 10 µg/ml of ponicidin on the cell proliferation was assessed. The viability of ponicidin-supplemented MG-63 cells was inspected by MTT test. The contents of osteocalcin, collagen, and ALP activity in the ponicidin administered cells were assessed by kits. The level of calcium mineralization was examined by ARS staining technique. The ponicidin treatment remarkably improved the proliferation of MG-63 cells. The ponicidin did not affect the MG-63 cells viability but promoted its viability 24- and 48-h treatment. The contents of osteocalcin, collagen, and ALP activity in the 5 and 10 µg/ml of ponicidin-supplemented MG-63 cells were found increased than the control cells. The ponicidin also increased the level of calcium deposition in MG-63 cells, which is assessed by ARS staining. In conclusion, it was clear that ponicidin improved the proliferation and calcium mineralization in a MG-63 cells. Therefore, it was clear that ponicidin has helpful roles on the new bone development as a hopeful therapeutic candidate to treat the bone-related disease like osteoporosis.


Asunto(s)
Calcio , Osteoporosis , Anciano , Fosfatasa Alcalina/metabolismo , Calcio/metabolismo , Diferenciación Celular , Proliferación Celular , Colágeno/farmacología , Diterpenos , Femenino , Humanos , Masculino , Osteoblastos/metabolismo , Osteocalcina/farmacología , Osteogénesis , Osteoporosis/tratamiento farmacológico
20.
Front Microbiol ; 13: 977171, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36033890

RESUMEN

Soil contamination with potentially toxic element such as chromium (Cr) poses a threat to the environment and human health. The environmental toxicity of Cr is related not only to the total Cr content but also to the distribution of Cr fractions. In this study, laboratory simulation experiments were conducted to explore the characteristics of Cr fractions and responses of the functional microbial community during dynamic leaching and static drying processes. The results showed that acid-soluble Cr and reducible Cr transformed into other relatively stable fractions under dry conditions, and ammonium nitrogen promoted the transformation. Nitrate-nitrogen was significantly positively correlated with Cr fractions in the wet stage (p < 0.05), while ammonium nitrogen showed the same relation in the dry process. Analysis of the microbial community showed that the bacterial and fungal genera Flavihumibacter, Altererythrobacter, Methylobacillus, Flavisolibacter, Lysobacter, and Cladosporium were related to the Cr fractions (acid-soluble Cr, reducible Cr, and oxidizable Cr) under wet conditions, while the microbial genera Ellin6067, MND1, and Ramlibacter were related to Cr fractions under dry conditions. Moreover, the proliferation of the functional microbial genera Methylobacillus, Ellin6067, and MND1 related to Cr fractions in the wet-dry conversion process alleviated the environmental toxicity of Cr. These findings provide useful information for the remediation of Cr-contaminated soils by monitoring the distribution fractions of Cr and the functional microbial community under wet-dry conditions.

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