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Understanding the microbial community structure in soil contaminated with heavy metals (HMs) is a precondition to conduct bioremediation in mine soil. Samples were collected from a typical lead-zinc (Pb-Zn) mine to assess the microbial community structure of the HMs concentrated in the soil. The goal was to analyze the bacterial and fungal community structures and their interactions using the 16S rRNA genes and internal transcribed spacer high-throughput sequencing. Analyses at different sampling sites showed that contamination with HMs significantly reduced the bacterial richness and diversity but increased that of the fungi. The predominant bacteria genera of Acidobacteriales, Gaiellales, Anaerolineaceae, Sulfurifustis, and Gemmatimonadaceae, and predominant fungal genera of Sordariomycetes, Talaromyces, and Mortierella were assumed as HM resistant genera in Pb-Zn mining area. The pH effect on the bacterial and fungal communities was opposite to those of Cd, Pb, and Zn. This study offers comprehensive outlooks for bacterial and fungal community structures upon multiple HM stresses in the soil around a typical Pb-Zn mine area.
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OBJECTIVES: Low-density lipoprotein cholesterol (LDLC) is the primary cholesterol target for the diagnosis and treatment of cardiovascular disease (CVD). Although beta-quantitation (BQ) is the gold standard to determine LDLC levels accurately, many clinical laboratories apply the Friedewald equation to calculate LDLC. As LDLC is an important risk factor for CVD, we evaluated the accuracy of Friedewald and alternative equations (Martin/Hopkins and Sampson) for LDLC. METHODS: We calculated LDLC based on three equations (Friedewald, Martin/Hopkins and Sampson) using the total cholesterol (TC), triglycerides (TG), and high-density lipoprotein cholesterol (HDLC) in commutable serum samples measured by clinical laboratories participating in the Health Sciences Authority (HSA) external quality assessment (EQA) programme over a 5 years period (number of datasets, n=345). LDLC calculated from the equations were comparatively evaluated against the reference values, determined from BQ-isotope dilution mass spectrometry (IDMS) with traceability to the International System of Units (SI). RESULTS: Among the three equations, Martin/Hopkins equation derived LDLC had the best linearity against direct measured (y=1.141x - 14.403; R2=0.8626) and traceable LDLC (y=1.1692x - 22.137; R2=0.9638). Martin/Hopkins equation (R2=0.9638) had the strongest R2 in association with traceable LDLC compared with the Friedewald (R2=0.9262) and Sampson (R2=0.9447) equation. The discordance with traceable LDLC was the lowest in Martin/Hopkins (median=-0.725%, IQR=6.914%) as compared to Friedewald (median=-4.094%, IQR=10.305%) and Sampson equation (median=-1.389%, IQR=9.972%). Martin/Hopkins was found to result in the lowest number of misclassifications, whereas Friedewald had the most numbers of misclassification. Samples with high TG, low HDLC and high LDLC had no misclassification by Martin/Hopkins equation, but Friedewald equation resulted in â¼50% misclassification in these samples. CONCLUSIONS: The Martin/Hopkins equation was found to achieve better agreement with the LDLC reference values as compared to Friedewald and Sampson equations, especially in samples with high TG and low HDLC. Martin/Hopkins derived LDLC also enabled a more accurate classification of LDLC levels.
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Doenças Cardiovasculares , Humanos , LDL-Colesterol , Valores de Referência , Triglicerídeos , HDL-Colesterol , Doenças Cardiovasculares/diagnósticoRESUMO
Urine albumin concentration and albumin-creatinine ratio are important for the screening of early-stage kidney damage. Commutable urine certified reference materials (CRMs) for albumin and creatinine are necessary for standardization of urine albumin and accurate measurement of albumin-urine ratio. Two urine CRMs for albumin and creatinine with certified values determined using higher-order reference measurement procedures were evaluated for their commutability on five brands/models of clinical analyzers where different reagent kits were used, including Roche Cobas c702, Roche Cobas c311, Siemens Atellica CH, Beckman Coulter AU5800, and Abbott Architect c16000. The commutability study was conducted by measuring at least 26 authentic patient urine samples and the human urine CRMs using both reference measurement procedures and the routine methods. Both the linear regression model suggested by the Clinical and Laboratory Standard Institute (CLSI) guidelines and log-transformed model recommended by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Commutability Working Group were used to evaluate the commutability of the human urine CRMs. The commutability of the human urine CRMs was found to be generally satisfactory on all five clinical analyzers for both albumin and creatinine, suggesting that they are suitable to be used routinely by clinical laboratories as quality control or for method validation of urine albumin and creatinine measurements.
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Albuminas , Modelos Estatísticos , Humanos , Creatinina , Padrões de Referência , Controle de QualidadeRESUMO
PURPOSE: Diamond has been regarded as a promising microdosimeter in radiation protection and radiotherapy due to its excellent properties. However, as the diamond is not tissue equivalent, a conversion of the measured spectra in the diamond microdosimeter to the tissue site is needed. In this work, we intend to deduce a method for converting the microdosimetric spectra from diamond to tissue in the proton therapy application based on the Chapman-Kolmogorov equation and investigate the validity of this method in spectral conversion. METHODS: The comparison of stopping power and energy deposition distribution of diamond and tissue shows that the conversion of the spectra in diamond to tissue can be performed by a simple scaling factor. Therefore, the equivalence of the energy deposition spectra in the diamond microdosimeter and a tissue site of the same size in the same radiation field was studied first to obtain the scaling factor. Then, the spectra conversion method was derived from the Chapman-Kolmogorov equation and the scaling factor. The Geant4 simulation was employed to settle this study. RESULTS: Theoretical and Geant4 simulation results indicate that the linear stopping power ratio of diamond to tissue is adequate to convert the microdosimetric spectra in diamond to tissue of identical dimension. The conversion results indicate that the energy deposition spectra converted from diamond to bone agree well with the spectra calculated by Geant4 along the Bragg curve. As for water, a good agreement of the converted and calculated spectra was found at the plateau of the Bragg curve and the distal part of the Bragg peak. At the proximal part of the Bragg peak, the converted and calculated spectrum is poorly coincident. CONCLUSIONS: The method of the energy deposition spectra conversion from the diamond microdosimeter to the tissue site of equal size shows relatively good results in most situations. But the deficiency was also found. Therefore, further investigation is needed to improve the reliability of this method.
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Terapia com Prótons , Simulação por Computador , Diamante , Método de Monte Carlo , Radiometria/métodos , Reprodutibilidade dos TestesRESUMO
BACKGROUND: To evaluate the cost-effectiveness of stage-based post-radiotherapy (PRT) nasopharyngeal carcinoma (NPC) surveillance strategies. METHODS: Four post-radiotherapy surveillance strategies were established by a Markov model based on data from 1664 patients: 1) clinical follow-up (CFP) with biannual Epstein-Barr virus (EBV) DNA (EBV DNA strategy); 2) CFP with biannual EBV DNA, annual head and neck magnetic resonance imaging (HNMRI), chest X-ray, abdominal ultrasonography, bone scan (only for the first two years) for five years (MCWU strategy); 3) CFP with biannual EBV DNA, annual HNMRI, chest, abdomen, pelvic computerized tomography (CT) and bone scan for the first two years, followed by annual MCWU strategy (without bone scans) for the last three years (CT strategy); 4) CFP with biannual EBV DNA, annual whole-body positron emission/computerized tomography (PET/CT) for the first two years and biannual EBV DNA for the last three years (PET/CT strategy). RESULTS: Compared with the EBV DNA strategy, the MCWU, CT, and PET/CT strategies gained 0.017, 0.047, and 0.082 quality-adjusted life years (QALY) for stage I-II patients. For stage III and IVa patients, the PET/CT strategy had a favorable incremental effectiveness (ICERs) of 0.277 and 0.385 QALY, respectively. The ICERs for the MCWU, CT, and PET/CT strategies were $74,037, $34,882, and $34,696 for stage III and $62,364, $27,981, and $28,340 for stage IVa, respectively. CONCLUSION: EBV DNA strategy was cost-effective for the long-term surveillance of stage I-II NPC patients with CR. PET/CT strategy was recommeded for patients having IVa NPC. As for stage III NPC, PET/CT strategy was still acceptable with the development of economy in China.
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Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Análise Custo-Benefício , DNA , DNA Viral/genética , Infecções por Vírus Epstein-Barr/epidemiologia , Herpesvirus Humano 4/genética , Humanos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia ComputadorizadaRESUMO
BACKGROUND: A chloride test is an integral part of a basic metabolic panel that is essential for the assessment of a patient's acid-base and electrolyte status. While many methods are available commercially for the routine measurement of chloride, there is a need to address the accuracy and variability among the measurement results, especially with the prevalence of patients seeking treatment across different healthcare providers for alternative opinions. METHOD: A method based on sector field inductively coupled plasma isotope dilution mass spectrometry (SF-ICP-IDMS) was developed for the measurement of chloride in human serum. The SF-ICP-IDMS method was then used to assign the target values in the Health Sciences Authority (HSA) External Quality Assessment (EQA) Programme to evaluate the results of chloride test from participating clinical laboratories. RESULTS: The accuracy of the measurements was evaluated by comparing the results with the certified values of Electrolytes in Frozen Human Serum Certified Reference Materials (SRM 956c and SRM 956d) from the National Institute of Standards and Technology (NIST) at different chloride concentration levels. Over a five-year period from 2014-2018, the number of clinical laboratories which participated in the EQA Programme increased from 23 to 33. Comparison of robust means from the laboratories' results with our assigned target values revealed a reduction in relative deviation over time. The relationship between the deviation of each brand of clinical analysers and the chloride levels was established, where a larger deviation was uncovered at low chloride concentration. The SF-ICP-IDMS method was further demonstrated to be comparable with methods used by other metrology institutes in an international comparison organised by HSA under the auspice of the Consultative Committee for Amount of Substance - Metrology in Chemistry and Biology (CCQM). CONCLUSION: The use of metrologically traceable assigned target values enabled the study of method biasness from a small pool of dataset in each of the four brands of clinical analysers in HSA EQA Programme. This work underscores the need to improve the accuracy of chloride measurements by regular participation in an accuracy-based EQA Programme.
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Cloretos , Laboratórios Clínicos , Eletrólitos , Humanos , Técnicas de Diluição do Indicador , Padrões de ReferênciaRESUMO
We aimed to assess the risks of Cryptosporidium and Giardia infections associated with drinking water for local residents, based on a quantitative microbial risk assessment, in three densely populated regions of China. In total, 45 source water samples and 45 treated water samples were collected from June to December 2014. Five Cryptosporidium-positive samples and 5 Giardia-positive samples were found. The annual probability of infection for individuals in Jintan (6.27 × 10 -4-2.05 × 10 -3 for Cryptosporidium and 7.18 × 10 -4-2.32 × 10 -3 for Giardia), Ezhou (6.27 × 10 -4-1.10 × 10 -2 for Cryptosporidium and 3.65 × 10 -4-1.20 × 10 -3 for Giardia), and Binyang (3.79 × 10 -4-1.25 × 10 -3 for Cryptosporidium) exceeded the tolerable risk of infection of 10 -4 set by the United States Environmental Protection Agency. Moreover, the corresponding disease burdens of cryptosporidiosis and giardiasis, due to direct drinking and residual water in these regions, exceeded the threshold of 10 -6 disability-adjusted life years per person per year set by the World Health Organization. These results provide insights into strategies to improve the safety of drinking water.
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Cryptosporidium/isolamento & purificação , Giardia/isolamento & purificação , Microbiologia da Água , Abastecimento de Água/estatística & dados numéricos , China , Criptosporidiose/microbiologia , Giardíase/microbiologia , Humanos , Medição de RiscoRESUMO
BACKGROUND: Shear wave-based ultrasonic elastography (USE) has been widely used for the assessment of liver fibrosis in patients with chronic liver diseases (CLD). However, diagnostic criteria and accuracy vary between different etiologies and specific elastography techniques. We aimed to evaluate the tissue stiffness measured by shear wave-based sound touch elastography (STE) in staging liver fibrosis in patients with autoimmune liver diseases (AILD). METHODS: One hundred and two AILD patients who had undergone STE liver stiffness measurements (LSMs) by using a Resona 7 ultrasound system were retrospectively studied. With the Scheuer liver fibrosis staging system as the reference, we investigated the diagnostic performance and cutoff values of STE measured liver stiffness in staging liver fibrosis through receiver operating characteristic (ROC) curve analysis. Moreover, comparisons of areas under the curve (AUCs) were made between LSMs and calculated biomarker scores, including the aspartate aminotransferase (AST)-to-platelet ratio index (APRI), and fibrosis-4 (FIB-4) index. RESULTS: Median LSMs increased with the advancing fibrosis stages with values of 6.89 kPa (1.51 m/s), 8.00 kPa (1.63 m/s), 9.60 kPa (1.79 m/s), 11.37 kPa (1.95 m/s) and 14.50 kPa (2.20 m/s), from stage 0 to stage 4 respectively. The cutoff values of STE for identifying significant fibrosis (≥ stage 2), severe fibrosis (≥ stage 3) and cirrhosis (stage 4) were 9.07 kPa (1.74 m/s), 9.97 kPa (1.82 m/s) and 10.48 kPa (1.87 m/s), respectively, with corresponding sensitivity of 79.1%, 93.3%, and 100%; specificity of 80.0%, 70.8% and 71.8%. The AUCs of LSMs in identifying fibrosis ≥ stage 2, ≥ stage 3 and stage 4 (0.82, 0.87, and 0.91, respectively) were significantly higher than that of APRI (0.67, 0.64, and 0.72, respectively) and FIB-4 (0.70, 0.68, and 0.75, respectively) (all P<0.05). CONCLUSIONS: LSM obtained by STE exhibited its good capability to evaluate liver fibrosis stages in patients with AILD. As a noninvasive modality for liver fibrosis staging, STE is superior to APRI and FIB-4 biomarker scores.
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OBJECTIVES: Urine albumin is measured in clinical laboratories by immunoturbidimetry. However, large biases are observed among the different routine methods. To standardize the measurement of urine albumin, a reference measurement procedure (RMP) and urine albumin certified reference materials (CRMs) are needed. METHODS: A candidate RMP for urine albumin based on liquid chromatography-isotope dilution tandem mass spectrometry (LC-IDMS/MS) using human serum albumin as calibration standard was developed. Isotope-labeled human albumin was used as internal standard. Urine samples were digested using trypsin and eight resulting "signature" peptides of albumin were quantified by LC-IDMS/MS. The candidate RMP was employed in value assignment of external quality assessment (EQA) samples and certification of urine albumin reference materials. The commutability of the developed CRMs was assessed against patient samples. RESULTS: The candidate RMP (recovery 101.5-103.2% and CV 1.2-3.3% at about 7-40 mg/L) met optimal performance goal. The lower limit of quantification was 0.03 mg/L as determined by signal-to-noise method. The EQA results from clinical laboratories using different immunoturbidimetric methods were generally comparable with assigned target values determined by the candidate RMP, with albumin concentrations ranging from 5 to 226 mg/L. Urine albumin reference materials (two levels) certified using the candidate RMP showed good commutability in a preliminary study. CONCLUSIONS: With optimal method precision and trueness, as well as comparability with routine methods, the developed RMP may be used for value assignment of EQA samples or certification of reference materials, which are important pillars in urine albumin method standardization.
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Laboratórios Clínicos , Espectrometria de Massas em Tandem , Albuminas , Certificação , Cromatografia Líquida , Humanos , Isótopos , Padrões de ReferênciaRESUMO
PURPOSE: To evaluate the diagnostic performance of sound touch elastography (STE) for staging liver fibrosis in chronic hepatitis B (CHB) patients using pathological stage of surgical specimens as the reference standard. METHOD: 239 CHB patients were included. Liver stiffness measurements (LSMs) on STE and Supersonic shear imaging (SSI), gamma glutamyl transferase-to-platelet ratio (GPR), aspartate aminotransferase-to-platelet ratio index (APRI) and four-factor Fibrosis-4 (FIB-4) index were obtained. Areas under the receiver operating characteristic (ROC) curves (AUCs) for the diagnosis of fibrosis stage were calculated and compared. RESULTS: The LSMs obtained by STE and SSI significantly correlated with the fibrosis stages (r = 0.757; r = 0.758, respectively, both p < 0.001). No significant differences in AUCs were observed between STE and SSI in identifying fibrosis ≥stage 1 (0.92 vs. 0.94), ≥stage 2 (0.89 vs. 0.91), ≥stage 3 (0.90 vs. 0.91) or stage 4 (0.92 vs. 0.91). Both STE and SSI had significantly higher AUCs in identifying each fibrosis stage than the GPR (0.68, 0.77, 0.76 and 0.79), APRI (0.53, 0.66, 0.74 and 0.69) and FIB-4 (0.61, 0.77, 0.79 and 0.74). CONCLUSIONS: STE is an efficient tool for assessing liver fibrosis in CHB patients, with performance comparable to that of SSI and superior to that of biomarkers.
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Técnicas de Imagem por Elasticidade , Hepatite B Crônica/diagnóstico por imagem , Hepatite B Crônica/cirurgia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/cirurgia , Tato , Área Sob a Curva , Biomarcadores/sangue , Fenômenos Biomecânicos , Biópsia , Feminino , Hepatite B Crônica/patologia , Hepatite B Crônica/fisiopatologia , Humanos , Fígado/patologia , Fígado/fisiopatologia , Fígado/cirurgia , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Curva ROC , gama-Glutamiltransferase/sangueRESUMO
Information is needed for comparative assessment and agronomic practices for phytoavoidation in multi-pollutant field. A field study was conducted to explore 97 Brassica pekinensis L. genotypes with permissible limit of contaminants growing in a severely Cd, moderately nitrate and slightly Pb multi-polluted field. Thirteen genotypes, i.e. KGZY, CXQW, CAIB, JINL, JQIN, JFEN, WMQF, XLSH, TAIK, BJXS, JUKA, XYJQ and GQBW, were identified with permissible limit for nitrate, Cd and Pb based on their resistance to heavy metal and nitrate accumulation in leaves when grown in co-contaminated soils. Furthermore, the correlation between essential and toxic elements concentrations in plant of B. pekinensis were inconsistent. Generally speaking, application of increasing Ca, K and S fertilizers in appropriate forms and dosages tended to increase the yield and quality of B. pekinensis cultivated in multi-pollutant field.
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Brassica , Poluentes Ambientais , Poluentes do Solo/análise , Biodegradação Ambiental , Cádmio/análise , Genótipo , Chumbo , SoloRESUMO
Phytoremediation is a valuable technology for mitigating soil contamination in agricultural lands, but phytoremediation without economic revenue is unfeasible for land owners and farmers. The use of crops with high biomass and bioenergy for phytoremediation is a unique strategy to derive supplementary benefits along with remediation activities. Sunflower (Helianthus annuus L.) is a high-biomass crop that can be used for the phytoremediation of polluted lands with additional advantages (biomass and oil). In this study, 40 germplasms of sunflower were screened in field conditions for phytoremediation with the possibility for oil and meal production. The study was carried out to the physiological maturity stage. All studied germplasms mopped up substantial concentrations of Pb, with maximum amounts in shootâ¯>â¯rootâ¯>â¯seed respectively. The phytoextraction efficiency of the germplasm was assessed in terms of the Transfer factor (TF), Metal removal efficiency (MRE) and Metal extraction ratio (MER). Among all assessed criteria, GP.8585 was found to be most appropriate for restoring moderately Pb-contaminated soil accompanied with providing high biomass and high yield production. The Pb content in the oil of GP.8585 was below the Food safety standard of China, with 59.5% oleic acid and 32.1% linoleic acid. Moreover, amino acid analysis in meal illustrated significant differences among essential and non-essential amino acids. Glutamic acid was found in the highest percentage (22.4%), whereas cysteine in the lowest percentage (1.3%). Therefore, its efficient phytoextraction ability and good quality edible oil and meal production makes GP.8585 the most convenient sunflower germplasm for phytoremediation of moderately Pb-contaminated soil, with fringe benefits to farmers and landowners.
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Biodegradação Ambiental , Helianthus/fisiologia , Chumbo , Poluentes do Solo/análise , Agricultura , Animais , Asteraceae , Biomassa , China , Produtos Agrícolas , Poluentes Ambientais , Helianthus/química , Humanos , Metais Pesados , Sementes/química , SoloRESUMO
Heavy metal removal by phytoremediation bears a great potential to decontaminate soils and Brassica juncea L. (Indian mustard) seems to be a possible candidate species for this purpose. A field experiment was conducted to compare the efficiency of eighty Indian mustard cultivars for phytoextraction of cadmium (Cd) and lead (Pb) from bimetal contaminated soil. Our results indicated that total Cd and Pb concentrations in the shoots and roots were in the range of 2.43⯱â¯0.00 to 0.31⯱â¯0.02â¯mg/kg and 2.94⯱â¯0.05 to 0.44⯱â¯0.03â¯mg/kg and 5.33⯱â¯0.76 to 0.47⯱â¯0.20â¯mg/kg and 3.78⯱â¯0.06 to 0.16⯱â¯0.08â¯mg/kg. Significant differences based on the translocation factors indicated that root-to-shoot transfer is higher for Pb (3.87⯱â¯0.12 to 0.48⯱â¯0.03) than Cd (3.38⯱â¯0.05 to 0.22⯱â¯0.01). Furthermore, significant correlations between dry weights, Cd and Pb concentrations and uptake in both shoots and roots were observed, but translocation factor showed a negative correlation with roots, but not in shoots. Among 80 genotypes of Indian mustard IM-25, IM-13 and IM-65 for Cd and IM-79, IM-24 and IM-32 for Pb seems to perform well for phytoextraction. The results of the field experiment suggest that certain Brassica juncea L. cultivars are suitable for removal of Cd and Pb in low to moderately contaminated soils.
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Cádmio/metabolismo , Chumbo/metabolismo , Mostardeira/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Cádmio/análise , Genótipo , Chumbo/análise , Mostardeira/genética , Poluentes do Solo/análiseRESUMO
BACKGROUND: With the diabetes mellitus (DM) prevalence increasing annually, the human grading of retinal images to evaluate DR has posed a substantial burden worldwide. SmartEye is a recently developed fundus image processing and analysis system with lesion quantification function for DR screening. It is sensitive to the lesion area and can automatically identify the lesion position and size. We reported the diabetic retinopathy (DR) grading results of SmartEye versus ophthalmologists in analyzing images captured with non-mydriatic fundus cameras in community healthcare centers, as well as DR lesion quantitative analysis results on different disease stages. METHODS: This is a cross-sectional study. All the fundus images were collected from the Shanghai Diabetic Eye Study in Diabetics (SDES) program from Apr 2016 to Aug 2017. 19,904 fundus images were acquired from 6013 diabetic patients. The grading results of ophthalmologists and SmartEye are compared. Lesion quantification of several images at different DR stages is also presented. RESULTS: The sensitivity for diagnosing no DR, mild NPDR (non-proliferative diabetic retinopathy), moderate NPDR, severe NPDR, PDR (proliferative diabetic retinopathy) are 86.19, 83.18, 88.64, 89.59, and 85.02%. The specificity are 63.07, 70.96, 64.16, 70.38, and 74.79%, respectively. The AUC are PDR, 0.80 (0.79, 0.81); severe NPDR, 0.80 (0.79, 0.80); moderate NPDR, 0.77 (0.76, 0.77); and mild NPDR, 0.78 (0.77, 0.79). Lesion quantification results showed that the total hemorrhage area, maximum hemorrhage area, total exudation area, and maximum exudation area increase with DR severity. CONCLUSIONS: SmartEye has a high diagnostic accuracy in DR screening program using non-mydriatic fundus cameras. SmartEye quantitative analysis may be an innovative and promising method of DR diagnosis and grading.
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Retinopatia Diabética/diagnóstico , Angiofluoresceinografia/métodos , Processamento de Imagem Assistida por Computador/métodos , Retina/diagnóstico por imagem , Seleção Visual/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Adulto JovemRESUMO
Since heavy metal pollution is widespread in street dust in China, the effects of heavy metals in street dust on human health cannot be ignored. However, studies estimating heavy metal pollution in street dust nationwide are limited. In this study, the concentrations of Cu, Zn, Cd and Pb in street dust at 3877sites throughout China were obtained from the published scientific literature. Based on these data, the contamination levels, spatial distributions, sources and potential health risks of heavy metals in street dust were comprehensively estimated. The results revealed that Cu, Zn, Cd and Pb levels are generally higher in the southeast provinces than in northwest China. In addition, traffic emissions and industrial activities are determined to be the two main sources of heavy metal pollution in street dust. The health risk assessment indicated that ingestion is the most important pathway of exposure to metal pollution in street dust for both children and adults, followed by dermal contact and inhalation. The spatial distribution of health risks suggested that the health risks are more serious in southeast China than in northwest China. The noncarcinogenic risks posed by Pb are relatively higher than those posed by the other three metals for both children and adults. Meanwhile, none of the hazard index (HI) values exceeded the safe level (1.0), with the exception of Pb in Daye city for children (HIâ¯=â¯1.074). The HI values for children were higher than those for adults. Therefore, children should be prioritized for protection from heavy metal pollution.
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Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poeira/análise , Exposição Ambiental/efeitos adversos , Metais Pesados/análise , Cádmio/análise , China , Cidades , Cobre/análise , Monitoramento Ambiental , Humanos , Chumbo/análise , Medição de Risco , Zinco/análiseRESUMO
Heavy metals including copper (Cu), zinc (Zn), cadmium (Cd), chromium (Cr), lead (Pb), and arsenic (As) were investigated in 89 pairs of rice plant and paddy soils around Dongting Lake area, China. Rice plants and soils were collected with GPS device, and heavy metal contents in different rice plant tissues and soils were measured. The aim of the present study was to assess the heavy metal pollution and translocation in the whole soil-rice system, including the consequent human health risk for residents. According to the indices of average geoaccumulation (Igeo) of the studied elements, paddy soils in study area were moderately polluted by Cd, lowly polluted by Pb, and not polluted by Cu, Zn, Cr, and As. Considering the much higher concentrations of studied elements in roots than in other tissues of rice plants, a great mass of these elements was assumed to be confined in the roots. The low translocation factors from root to shoot (Tfroot-shoot) of all the studied heavy metals (0.04-0.74) underpinned this. The high translocation factors from soil to root (Tfsoil-root) of Cd (9.12), As (4.38), and Zn (2.05) indicated the high bioavailability of these heavy metals for rice plant. The health risk assessment using target hazard quotients (THQs) model indicated that Cd (5.17 for adults and 4.49 for children respectively) and As (3.61 for adults and 3.14 for children respectively) could cause human health risk both for adults and children. Further, given the rate of individual THQ values exceeding one, Cu might also be considered as a potential human health dangerous element in the study area. It was worth noting that as one of the main pollutants, Pb did not show human health risk through rice grain consumption due to its low Tf values in soil-rice system. However, the risk identification of As using comparisons of measured concentrations with risk screening value in Chinese paddy soil standard (GB15618-2018) was not consistent with the human health risk assessment result. This might indicate that site-specific risk screening values of As in China is in demand.
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Agricultura , Exposição Ambiental/análise , Metais Pesados/análise , Poluentes do Solo/análise , Adulto , Arsênio , Cádmio/análise , Criança , China , Cobre/análise , Grão Comestível/química , Exposição Ambiental/estatística & dados numéricos , Poluição Ambiental , Humanos , Lagos , Oryza/química , Medição de Risco , Solo/química , ZincoRESUMO
Stairway dust samples were collected from residential communities in Huludao city to investigate population health risk of arsenic (As) exposure through stairway dust. ArcGIS software was used to analyze As spatial distribution in Huludao city. Hazard index was applied to assess health risk due to exposure to As in stairway dust. The results were that As concentrations ranged from 13.26 to 237.58 mg kg-1, and the mean value was 59.64 mg kg-1, which was seven times as high as the background value of Liaoning Province. The pattern of spatial distribution was concentric rings as the center of Huludao zinc plant, with the extension to the northeast and southwest. The average value of Igeo was 2.176, which fell into moderately polluted level. For non-carcinogenic risk, the hazard indexes were less than 1, indicating that there was almost no health risk for residents exposed to stairway dust. But population risk exposure to dust would increase rapidly with exposure time in stairway. The highest contribution to the overall figure of non-carcinogenic risk and carcinogenic risk appeared to be ingestion of substrate particles followed by inhalation pathway and dermal absorption of As in dust samples. And for carcinogenic risk, the risk values were lower than the threshold range of EPA's safe limits (1 × 10-6 and 1 × 10-4), suggesting that potential cancer risk of As due to exposure to stairway dust can be acceptable.
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Arsênio/análise , Poeira/análise , Monitoramento Ambiental/métodos , Zinco/análise , China , Cidades , Poluentes Ambientais/análise , Poluição Ambiental/análise , Humanos , Medição de Risco/métodosRESUMO
In this paper, the interaction between bovine lactoferrin (bLf) and tetracycline hydrochloride (TCH) was researched by microscale thermophoresis (MST), multi-spectroscopic methods, and molecular docking techniques. Normal fluorescence results showed that TCH effectively quenched the intrinsic fluorescence of bLf via static quenching. Moreover, MST confirmed that the combination force between bLf and TCH was very strong. Thermodynamic parameters and molecular docking further revealed that electrostatic forces, van der Waals, and hydrogen bonding forces played vital roles in the interaction between bLf and TCH. The binding distance and energy transfer efficiency between TCH and bLf were 2.81 nm and 0.053, respectively. Moreover, the results of circular dichroism spectra (CD), ultraviolet visible (UV-vis) absorption spectra, fluorescence Excitation-Emission Matrix (EEM) spectra, and molecular docking verified bLf indeed combined with TCH, and caused the changes of conformation of bLf. The influence of TCH on the functional changes of the protein was studied through the analysis of the change of the bLf surface hydrophobicity and research of the binding forces between bLf and iron ion. These results indicated that change in the structure and function of bLf were due to the interaction between bLf and TCH.
Assuntos
Ferro/química , Lactoferrina/química , Simulação de Acoplamento Molecular , Tetraciclina/química , Animais , Bovinos , Transferência de Energia , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Imagem Óptica , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Soluções , Espectrometria de Fluorescência , Eletricidade Estática , TermodinâmicaRESUMO
The Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM) supported a project on the control and elimination of malaria in People's Republic of China which was one of the biggest-scale international cooperation programmes to control malaria in the country during the past 10 years. The project promoted the effective implementation of the Chinese national malaria control programme. On the basis of epidemiologic data, an overview of the project activities and key performance indicators, the overall impact of the GFATM project was evaluated. We also reviewed relevant programme features including technological and management approaches, with a focus on best practice, innovations in implementation and the introduction of international standards. Last, we summarised the multi-stakeholder cooperation mechanism and comments on its sustainability in the post-GFATM period. Recommendations for the future management of the Chinese national malaria elimination programme are put forward after considering the challenges, shortcomings and lessons learnt during the implementation of the GFATM project in China to sustain past achievements and foster the attainment of the ultimate goal of malaria elimination for the country.