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1.
J Environ Manage ; 347: 119117, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37806271

RESUMEN

A comprehensive assessment of the heavy metal system in the rehabilitated saline-alkali land holds significant importance, as the in-situ remediation process utilizing amendments substantially alters the initial physicochemical properties of the soil, which could lead to the migration or reactivation of previously stabilized heavy metals. In this context, the present study aims to evaluate the heavy metal content and health risk within the improved saline-alkali soil-plant system. Moreover, a comprehensive evaluation based on the TOPSIS-RSR method is carried out to accurately gauge the soil health status. The findings indicate that the modification process has an impact on the concentrations of heavy metals in the soil and crops, causing either an increase or decrease. However, the level of heavy metal pollution in the improved saline-alkali soil and rape remains within safe limits. The results of the migration of heavy metals after amendment application indicated that the migration of heavy metals in the soil was influenced by the properties of the heavy metals, the composition of the amendment, and leaching. Furthermore, the total non-carcinogenic hazard quotients in the soil and rape were within the safe threshold for all populations. The findings provided novel insights into the status and risk assessment of the pollution of improved saline-alkali soil.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Contaminantes del Suelo/análisis , Metales Pesados/química , Suelo , Contaminación Ambiental/análisis , Productos Agrícolas , Medición de Riesgo , Monitoreo del Ambiente , China
2.
Zhonghua Nan Ke Xue ; 26(1): 59-62, 2020 Jan.
Artículo en Zh | MEDLINE | ID: mdl-33345479

RESUMEN

OBJECTIVE: To study the semen parameters of infertile men carrying hepatitis B virus (HBV) and the influence of HBV infection on semen quality. METHODS: We collected the semen samples from 782 infertility males aged 25-35 years old. According to the results of serological examinations, we divided the patients into groups A (HBsAg, HBeAb and HBcAb positive, n = 286), B (HBsAg, HBeAg and HBcAb positive, n = 230) and C (non-HBV control, n = 266), and comparatively analyzed the routine semen parameters, sperm acrosin activity, sperm DNA fragmentation index (DFI) and high DNA stainability (HDS) among the three groups of patients. RESULTS: Compared with the patients of groups B and C, those of group A showed markedly decreased sperm concentration (ï¼»88.20 ± 82.62ï¼½ and ï¼»89.29 ± 53.80ï¼½ vs ï¼»71.49 ± 60.03ï¼½ ×106/ml, P<0.05), progressively motile sperm (PMS) (ï¼»34.88 ± 15.60ï¼½% and ï¼»37.82 ± 13.63ï¼½% vs ï¼»30.70 ± 14.79ï¼½%, P<0.05), sperm motility (ï¼»45.77 ± 16.58ï¼½% and ï¼»48.16 ± 14.03ï¼½% vs ï¼»42.67 ± 17.23ï¼½%, P<0.05), sperm viability (ï¼»82.55 ± 7.55ï¼½% and ï¼»85.26 ± 6.39ï¼½% vs ï¼»81.07 ± 10.19ï¼½%, P>0.05) and morphologically normal sperm (MNS) (ï¼»6.93 ± 4.45ï¼½% and ï¼»7.27 ± 4.43ï¼½% vs ï¼»5.72 ± 3.47ï¼½%, P<0.05), with sperm concentration, PMS, sperm motility, sperm viability and MNS remarkably lower in group B than in C. Sperm acrosin activity was significantly reduced in group A in comparison with groups B and C (ï¼»57.07 ± 26.38ï¼½ vs ï¼»63.03 ± 28.75ï¼½ and ï¼»78.00 ± 33.49ï¼½ µIU/106, P<0.01), remarkably lower in group B than in C (P<0.01). The sperm DFI and HDS, however, were markedly higher in group A than in B (ï¼»14.79 ± 9.46ï¼½% vs ï¼»12.95 ± 7.29ï¼½% and ï¼»11.60 ± 5.98ï¼½%, P<0.05; ï¼»9.62 ± 6.20ï¼½% vs ï¼»8.43 ± 4.72ï¼½% and ï¼»8.41 ± 4.59ï¼½%, P<0.05), and both higher in group B than in C. CONCLUSIONS: Semen quality is lower in infertile men carrying HBV and therefore HBV infection is one of the causes of male infertility.


Asunto(s)
Hepatitis B/complicaciones , Infertilidad Masculina/etiología , Análisis de Semen , Adulto , Fragmentación del ADN , Humanos , Masculino , Semen , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides
3.
Chemosphere ; 321: 138127, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36780996

RESUMEN

Titanium gypsum and biochar are considered effective amendments for mitigating soil salinity stress. However, the knowledge is inadequate regarding their efficiency and application as an improvement. In this study, TG-B composite was prepared by using industrial by-products titanium gypsum and biochar as raw materials and then modified by ball milling method, to characterize its microscopic characteristics and explore the improvement effect on saline-alkali soil and plant growth. Besides, we explored the mechanism of TG-B in improving saline-alkali soil and the dynamic balance of the solution reaction process. Our results showed that the CaSO4·2H2O particles in TG-B were finer, dispersed evenly, and contacted fully with soil gelatinous particles, which was more conducive to the improvement of saline-alkali soil. The results of TG-B with different ball milling ratios and different materials dosages indicated that the application rate of TG-B was 5%, and the optimum ratio of TG-B was TG: B (mass ratio) = 10:1, with the best soil improvement effect. The pot experiment proved that the indicators of indicating soil salinity such as pH, EC, SAR, and soluble Na+ decreased by 20.74%, 77.24%, 68.77%, and 44.70%, respectively, thus playing a good role in improving saline-alkali soil. In addition, pot experiments demonstrated that compared with the control group, the soil porosity and soil moisture content in the TG-B group increased by 15.95% and 38.71%, respectively, and further improve the structure and diversity of soil bacterial community when compared with titanium gypsum and biochar alone. Finally, the application of TG-B promoted the germination and growth of rice significantly through the synergistic effects of composite material components. These results all suggested that the application of TG-B was an effective strategy to improve soil salinity and promote plant growth. Therefore, it might provide new insights into the utilization of solid waste resources to improve saline-alkali lands.


Asunto(s)
Sulfato de Calcio , Suelo , Suelo/química , Sulfato de Calcio/química , Titanio , Carbón Orgánico , Álcalis , Estrés Salino , Salinidad
4.
Sci Total Environ ; 905: 167179, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37730027

RESUMEN

The combination of amendments has emerged as a potential strategy to efficiently alleviate salt stress in saline-alkali soil. However, knowledge regarding how to optimize the proportion of different amendment materials, comprehensively assess the contribution of each component, and clarify the response mechanisms of the amendment-saline-alkali soil-plant system is incomplete. Based on this, we conducted a pot experiment to evaluate the improvement effect of the combined application of different amendment materials at varying levels and the contribution of the amendment components to alleviating salt stress. Overall, T6 exhibited the most significant improvement effect on the physicochemical and biological properties of the saline-alkali soil and promoted the growth of oilseed rape, with the levels of 2.0 % phosphogypsum, 2.0 % humic acid, 0.25 % bentonite, and 0.03 % sodium carboxymethyl cellulose. Compared with the control group, the EC decreased by 1.51 % to 33.49 %, the soil salt content dropped by 11.40 % to 35.46 %, and the soil soluble Na + concentration significantly declined by 39.47 % to 63.20 %. Additionally, the soil nutrient content and soil microbial community structure were enhanced in treatment groups. Meanwhile, amendments alleviated salt stress in the oilseed rape plant by activating anti-oxidative enzymes and osmoregulatory substances such as soluble sugar and proline, thus improving their ability to remove reactive oxygen species (ROS). The anti-oxidative enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were significantly increased, with an increase of 10.68 % (SOD, T2) ∼207.31 % (CAT, T6) compared to the control group. The structural equation modeling (SEM) analysis and simulation experiments indicated that the amendment components synergically promoted the amelioration effect on salt stress, and effectively improved soil properties, which affected the response of oilseed rape to soil environment. This research paper provides the relevant reference for the combined application of different amendment materials for soil reclamation.


Asunto(s)
Álcalis , Suelo , Suelo/química , Plantas , Sustancias Húmicas , Superóxido Dismutasa
5.
Neuroimage ; 59(2): 1275-89, 2012 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-21884801

RESUMEN

Longitudinal atlas construction plays an important role in medical image analysis. Given a set of longitudinal images from different subjects, the task of longitudinal atlas construction is to build an atlas sequence which can represent the trend of anatomical changes of the population. The major challenge for longitudinal atlas construction is how to effectively incorporate both the subject-specific information and population information to build the unbiased atlases. In this paper, a novel groupwise longitudinal atlas construction framework is proposed to address this challenge, and the main contributions of the proposed framework lie in the following aspects: (1) The subject-specific longitudinal information is captured by building the growth model for each subject. (2) The longitudinal atlas sequence is constructed by performing groupwise registration among all the subject image sequences, and only one transformation is needed to transform each subject's image sequence to the atlas space. The constructed longitudinal atlases are unbiased and no explicit template is assumed. (3) The proposed method is general, where the number of longitudinal images of each subject and the time points at which they are taken can be different. The proposed method is extensively evaluated on two longitudinal databases, namely the BLSA and ADNI databases, to construct the longitudinal atlas sequence. It is also compared with a state-of-the-art longitudinal atlas construction algorithm based on kernel regression on the temporal domain. Experimental results demonstrate that the proposed method consistently achieves higher registration accuracies and more consistent spatial-temporal correspondences than the compared method on both databases.


Asunto(s)
Algoritmos , Encéfalo/anatomía & histología , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Modelos Anatómicos , Reconocimiento de Normas Patrones Automatizadas/métodos , Técnica de Sustracción , Simulación por Computador , Humanos , Aumento de la Imagen/métodos , Estudios Longitudinales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
Neuroimage ; 59(1): 422-30, 2012 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-21807102

RESUMEN

In this paper, we present a multi-atlas-based framework for accurate, consistent and simultaneous segmentation of a group of target images. Multi-atlas-based segmentation algorithms consider concurrently complementary information from multiple atlases to produce optimal segmentation outcomes. However, the accuracy of these algorithms relies heavily on the precise alignment of the atlases with the target image. In particular, the commonly used pairwise registration may result in inaccurate alignment especially between images with large shape differences. Additionally, when segmenting a group of target images, most current methods consider these images independently with disregard of their correlation, thus resulting in inconsistent segmentations of the same structures across different target images. We propose two novel strategies to address these limitations: 1) a novel tree-based groupwise registration method for concurrent alignment of both the atlases and the target images, and 2) an iterative groupwise segmentation method for simultaneous consideration of segmentation information propagated from all available images, including the atlases and other newly segmented target images. Evaluation based on various datasets indicates that the proposed multi-atlas-based multi-image segmentation (MABMIS) framework yields substantial improvements in terms of consistency and accuracy over methods that do not consider the group of target images holistically.


Asunto(s)
Algoritmos , Mapeo Encefálico/métodos , Interpretación de Imagen Asistida por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Encéfalo/anatomía & histología , Humanos
7.
Hum Brain Mapp ; 33(2): 253-71, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21391266

RESUMEN

Groupwise registration has been widely investigated in recent years due to its importance in analyzing population data in many clinical applications. To our best knowledge, most of the groupwise registration algorithms only utilize the intensity information. However, it is well known that using intensity only is not sufficient to achieve the anatomically sound correspondences in medical image registration. In this article, we propose a novel feature-based groupwise registration algorithm to establish the anatomical correspondence across subjects by using the attribute vector that is defined as the morphological signature for each voxel. Similar to most of the state-of-the-art groupwise registration algorithms, which simultaneously estimate the transformation fields for all subjects, we develop an energy function to minimize the intersubject discrepancies on anatomical structures and drive all subjects toward the hidden common space. To make the algorithm efficient and robust, we decouple the complex groupwise registration problem into two easy-to-solve subproblems, namely (1) robust correspondence detection and (2) dense transformation field estimation, which are systematically integrated into a unified framework. To achieve the robust correspondences in the step (1), several strategies are adopted. First, the procedure of feature matching is evaluated within a neighborhood, rather than only on a single voxel. Second, the driving voxels with distinctive image features are designed to drive the transformations of other nondriving voxels. Third, we take advantage of soft correspondence assignment not only in the spatial domain but also across the population of subjects. Specifically, multiple correspondences are allowed to alleviate the ambiguity in establishing correspondences w.r.t. a particular subject and also the contributions from different subjects are dynamically controlled throughout the registration. Eventually in the step (2), based on the correspondences established for the driving voxels, thin-plate spline is used to propagate correspondences on the driving voxels to other locations in the image. By iteratively repeating correspondence detection and dense deformation estimation, all the subjects will be aligned onto the common space. Our feature-based groupwise registration algorithm has been extensively evaluated over 18 elderly brains, 16 brains from NIREP (with 32 manually delineated labels), 40 brains from LONI LPBA40 (with 54 manually delineated labels), and 12 pairs of normal controls and simulated atrophic brain images. In all experiments, our algorithm achieves more robust and accurate registration results, compared with another groupwise algorithm and a pairwise registration method.


Asunto(s)
Algoritmos , Encéfalo/anatomía & histología , Interpretación de Imagen Asistida por Computador/métodos , Sistema de Registros , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Masculino
8.
Neuroimage ; 56(4): 1968-81, 2011 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-21440646

RESUMEN

Groupwise registration has become more and more popular due to its attractiveness for unbiased analysis of population data. One of the most popular approaches for groupwise registration is to iteratively calculate the group mean image and then register all subject images towards the latest estimated group mean image. However, its performance might be undermined by the fuzzy mean image estimated in the very beginning of groupwise registration procedure, because all subject images are far from being well-aligned at that moment. In this paper, we first point out the significance of always keeping the group mean image sharp and clear throughout the entire groupwise registration procedure, which is intuitively important but has not been explored in the literature yet. To achieve this, we resort to developing the robust mean-image estimator by the adaptive weighting strategy, where the weights are adaptive across not only the individual subject images but also all spatial locations in the image domain. On the other hand, we notice that some subjects might have large anatomical variations from the group mean image, which challenges most of the state-of-the-art registration algorithms. To ensure good registration results in each iteration, we explore the manifold of subject images and build a minimal spanning tree (MST) with the group mean image as the root of the MST. Therefore, each subject image is only registered to its parent node often with similar shapes, and its overall transformation to the group mean image space is obtained by concatenating all deformations along the paths connecting itself to the root of the MST (the group mean image). As a result, all the subjects will be well aligned to the group mean image adaptively. Our method has been evaluated in both real and simulated datasets. In all experiments, our method outperforms the conventional algorithm which generally produces a fuzzy group mean image throughout the entire groupwise registration.


Asunto(s)
Algoritmos , Encéfalo/anatomía & histología , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino
9.
Neuroimage ; 54(2): 928-39, 2011 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-20851197

RESUMEN

Registration of a population of diffusion tensor images (DTIs) is one of the key steps in medical image analysis, and it plays an important role in the statistical analysis of white matter related neurological diseases. However, pairwise registration with respect to a pre-selected template may not give precise results if the selected template deviates significantly from the distribution of images. To cater for more accurate and consistent registration, a novel framework is proposed for groupwise registration with the guidance from one or more intermediate templates determined from the population of images. Specifically, we first use a Euclidean distance, defined as a combinative measure based on the FA map and ADC map, for gauging the similarity of each pair of DTIs. A fully connected graph is then built with each node denoting an image and each edge denoting the distance between a pair of images. The root template image is determined automatically as the image with the overall shortest path length to all other images on the minimum spanning tree (MST) of the graph. Finally, a sequence of registration steps is applied to progressively warping each image towards the root template image with the help of intermediate templates distributed along its path to the root node on the MST. Extensive experimental results using diffusion tensor images of real subjects indicate that registration accuracy and fiber tract alignment are significantly improved, compared with the direct registration from each image to the root template image.


Asunto(s)
Mapeo Encefálico/métodos , Imagen de Difusión por Resonancia Magnética , Interpretación de Imagen Asistida por Computador/métodos , Encéfalo/fisiología , Humanos
10.
Neuroimage ; 51(3): 1057-70, 2010 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20226255

RESUMEN

To achieve more accurate and consistent registration in an image population, a novel hierarchical groupwise registration framework, called Atlas Building by Self-Organized Registration and Bundling (ABSORB), is proposed in this paper. In this new framework, the global structure, i.e., the relative distribution of subject images is always preserved during the registration process by constraining each subject image to deform only locally with respect to its neighbors within the learned image manifold. To achieve this goal, two novel strategies, i.e., the self-organized registration by warping one image towards a set of its eligible neighbors and image bundling to cluster similar images, are specially proposed. By using these two strategies, this new framework can perform groupwise registration in a hierarchical way. Specifically, in the high level, it will perform on a much smaller dataset formed by the representative subject images of all subgroups that are generated in the previous levels of registration. Compared to the other groupwise registration methods, our proposed framework has several advantages: (1) it explores the local data distribution and uses the obtained distribution information to guide the registration; (2) the possible registration error can be greatly reduced by requiring each individual subject to move only towards its nearby subjects with similar structures; (3) it can produce a smoother registration path, in general, from each subject image to the final built atlas than other groupwise registration methods. Experimental results on both synthetic and real datasets show that the proposed framework can achieve substantial improvements, compared to the other two widely used groupwise registration methods, in terms of both registration accuracy and robustness.


Asunto(s)
Encéfalo/anatomía & histología , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Modelos Anatómicos , Modelos Neurológicos , Reconocimiento de Normas Patrones Automatizadas/métodos , Algoritmos , Simulación por Computador , Humanos , Aumento de la Imagen/métodos , Imagenología Tridimensional/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
IEEE Trans Pattern Anal Mach Intell ; 31(5): 841-54, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19299859

RESUMEN

The task of finding a low-rank (r) matrix that best fits an original data matrix of higher rank is a recurring problem in science and engineering. The problem becomes especially difficult when the original data matrix has some missing entries and contains an unknown additive noise term in the remaining elements. The former problem can be solved by concatenating a set of r-column matrices that share a common single r-dimensional solution space. Unfortunately, the number of possible submatrices is generally very large and, hence, the results obtained with one set of r-column matrices will generally be different from that captured by a different set. Ideally, we would like to find that solution that is least affected by noise. This requires that we determine which of the r-column matrices (i.e., which of the original feature points) are less influenced by the unknown noise term. This paper presents a criterion to successfully carry out such a selection. Our key result is to formally prove that the more distinct the r vectors of the r-column matrices are, the less they are swayed by noise. This key result is then combined with the use of a noise model to derive an upper bound for the effect that noise and occlusions have on each of the r-column matrices. It is shown how this criterion can be effectively used to recover the noise-free matrix of rank r. Finally, we derive the affine and projective structure-from-motion (SFM) algorithms using the proposed criterion. Extensive validation on synthetic and real data sets shows the superiority of the proposed approach over the state of the art.


Asunto(s)
Algoritmos , Inteligencia Artificial , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Movimiento , Reconocimiento de Normas Patrones Automatizadas/métodos , Fotograbar/métodos , Aumento de la Imagen/métodos , Movimiento (Física) , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
World J Gastroenterol ; 14(2): 218-23, 2008 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-18186558

RESUMEN

AIM: To determine platelet activating factor (PAF) receptor expression in cirrhotic hepatic stellate cells. METHODS: Hepatic stellate cells, isolated from the livers of control and CCl(4)-induced cirrhotic rats, were placed in serum-free medium after overnight culture. We determined the PAF receptor in hepatic stellate cells by saturation binding technique and semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR), and the effects of PAF and its antagonist BN52021 on prostaglandin E(2) (PGE(2)) release by stellate cells. RESULTS: Scatchard analysis indicated the presence of PAF receptor with dissociation constant (Kd) of 4.66 nmol/L and maximum binding capacity (Bmax) of 24.65 fmol/microg in cirrhotic stellate cells. Compared with the control, the maximum PAF binding capacity increased significantly (Bmax: 24.65 +/- 1.96 fmol/microg. DNA, R = 0.982 vs 5.74 +/- 1.55 fmol/microg. DNA, R = 0.93; P < 0.01), whereas receptor affinity had no significant difference (Kd of 4.66 +/- 0.33 nmol/L for the cirrhosis and 3.51 +/- 0.26 nmol/L for the control; P > 0.05). Consistent with the receptor binding data, the mRNA expression of PAF receptor was increased significantly in cirrhotic stellate cells. PAF in a concentration-dependent manner induced PGE(2) synthesis in cirrhotic hepatic stellate cells, but the effects were blocked significantly by BN52021. CONCLUSION: Cirrhosis sensitizes hepatic stellate cells to PAF by elevating its receptor level and hepatic stellate cells maybe potential effectors of PAF induced portal hypertension.


Asunto(s)
Hepatocitos/fisiología , Hipertensión Portal/metabolismo , Cirrosis Hepática/metabolismo , Factor de Activación Plaquetaria/metabolismo , Glicoproteínas de Membrana Plaquetaria/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animales , Hepatocitos/patología , Hipertensión Portal/patología , Hipertensión Portal/fisiopatología , Cirrosis Hepática/patología , Masculino , Glicoproteínas de Membrana Plaquetaria/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores Acoplados a Proteínas G/genética
13.
PLoS One ; 13(8): e0201820, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30096162

RESUMEN

INTRODUCTION: Hepatitis B is a serious public health problem across sub-Saharan Africa. Sierra Leone has no national hepatitis B strategy plan or high quality estimates of prevalence. Healthcare workers are perceived as an at-risk group for hepatitis B. We assessed the prevalence of hepatitis B among healthcare workers at two hospital sites in Freetown, Sierra Leone. METHODS: In October 2017, healthcare workers were offered voluntary testing for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), hepatitis B core antibody (anti-HBc), hepatitis B e antigen (HBeAg) and hepatitis B e antibody (anti-HBe) using rapid lateral flow assay for all samples, followed by Enzyme Immunosorbent Assay to confirm positive results. Participants completed a questionnaire about knowledge, attitudes and practices concerning hepatitis B. HBsAg positive participants were invited to a clinic for further assessment. RESULTS: Overall, 447 participants were tested for hepatitis B. Most (90.6%, 405/447) participants were nurses, 72.3% (323/447) were female and 71.6% (320/447) were 30 years or older. The prevalence of chronic hepatitis B (HBsAg positivity) was 8.7% (39 / 447, 95% CI 6.3-11.7%). There was no significant difference in prevalence by sex, age group, site of work or type of job. None of the 66.7% (26 / 39) of participants with chronic hepatitis B who attended the clinic met the 2015 WHO criteria to start treatment for hepatitis B on the basis of cirrhosis. Most participants (96.9% 432 / 446) stated that they were worried about their risk of hepatitis B at work. CONCLUSIONS: Hepatitis B is highly prevalent among healthcare workers in Sierra Leone. It is unclear whether this reflects high community prevalence or is due to occupational risk. No participants with chronic hepatitis B needed to start treatment. In order to achieve the WHO target of elimination of viral hepatitis by 2030, introduction of birth dose vaccine for infants and catch-up vaccines for healthcare workers and healthcare students, together with a national hepatitis B screen and treat programme is advisable for Sierra Leone.


Asunto(s)
Personal de Salud , Hepatitis B Crónica/epidemiología , Adulto , Anticuerpos Antivirales/sangre , Estudios Transversales , Femenino , Humanos , Masculino , Prevalencia , Sierra Leona/epidemiología , Población Urbana
14.
Minerva Med ; 108(1): 57-73, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27824246

RESUMEN

BACKGROUND: The association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and breast cancer risk has been extensively explored, but their results are conflicting rather than conclusive. To clarify the precise effects of MTHFR polymorphisms on the risk of breast cancer, a systemic review and most comprehensive meta-analysis of all available studies relating MTHFR rs1801133 gene polymorphism to the risk of breast cancer was conducted. METHODS: Eligible articles were identified by search of databases including Medline (Mainly PubMed), Embase, Web of Science, Chinese Biomedical Literature database (CBM), CNKI and Wanfang Medical databases. Crude ORs with 95% CIs were used to assess the strength of association. RESULTS: Finally, a total of 83 studies with 35,029 cases and 38,990 controls were included. Overall, MTHFR rs1801133 gene polymorphism was proved to contribute to the risk of breast cancer under all genetic models (TT vs. CC: Pheterogeneity <0.001, OR=1.141, 95%CI=1.065-1.222, P <0.001; TT vs. CT: Pheterogeneity <0.001, OR=1.085, 95%CI=1.021-1.154, P=0.009; TT + CT vs. CC: Pheterogeneity <0.001, OR=1.040, 95%CI=1.020-1.061, P <0.001; TT vs. CC + CT: Pheterogeneity <0.001, OR=1.131, 95%CI=1.052-1.215, P=0.0478; T allele vs. C allele: Pheterogeneity <0.001, OR=1.040, 95%CI=1.009-1.071, P=0.010). CONCLUSIONS: The results of this meta-analysis suggest that MTHFR rs1801133 gene polymorphism may the therapeutic target for breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo de Nucleótido Simple , Alelos , Neoplasias de la Mama/epidemiología , Etnicidad/genética , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos
15.
World J Gastroenterol ; 12(30): 4859-65, 2006 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-16937468

RESUMEN

AIM: To observe the effects of augmenter of liver regeneration (ALR) on Kupffer cells and to determine whether ALR promotes hepatocyte proliferation induced by Kupffer cells. METHODS: Kupffer cells and hepatocytes were cultured in vitro and various concentrations of recombinant rat ALR (rrALR) were added. 3H-thymidine, BrdU and 3H-leucine incorporation was determined in cultured Kupffer cells and hepatocytes, in hepatocytes conditioned by Kupffer cells, and in associated medium. rrALR was labeled by iodination and used to determine its binding activity by Scatchard analysis in Kupffer cells and primarily cultured rat hepatocytes. RESULTS: rrALR stimulated DNA replication in Kupffer cells and protein synthesis both in cells and in medium in a non-concentration-dependent manner. The effect was significant at the concentration of 1 microg/L ALR. However, rrALR had no effect on primarily cultured hepatocytes, when hepatocytes were cultured with the Kupffer cell medium conditioned by ALR, DNA replication and protein synthesis in hepatocytes increased significantly at the concentration of 1 microg/L ALR. When the ALR concentration was increased, its effect on hepatocyte proliferation decreased to the basal level. Scatchard analysis indicated the presence of a single class of high affinity receptors with a dissociation constant (Kd) of 0.883 nmol/L and a maximum binding capacity (Bmax) of 126.1 pmol/g protein in the rat Kupffer cells. CONCLUSION: ALR can promote hepatocyte proliferation induced by Kupffer cells, which is associated with the concentration of ALR, suggesting that Kupffer cells play a dual role in liver regeneration.


Asunto(s)
Proliferación Celular , Hepatocitos/fisiología , Macrófagos del Hígado/metabolismo , Regeneración Hepática/fisiología , Proteínas/metabolismo , Animales , Células Cultivadas , Medios de Cultivo Condicionados/química , Hepatocitos/citología , Humanos , Macrófagos del Hígado/citología , Masculino , Proteínas/genética , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
16.
Minerva Med ; 2016 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-27119826

RESUMEN

BACKGROUND: Single nucleotide polymorphism in miRNAs can alter its expression, thus lead to the development of cancers. Numerous studies have explored the association between miR-149 gene rs2292832 polymorphism and hepatocellular carcinoma risk, but the results remains inconsistent. So, we performed this pooled analyses in order to get a precise result. METHODS: Odds ratios (OR) with 95% confidence intervals (CI), calculated by STATA software, were used to determine whether miR-149 gene rs2292832 polymorphism contributes to the risk of Hepatocellular carcinoma. A comprehensive literature search was conducted on Medline (mainly PubMed), Cochrane Library database, Web of science and the China National Knowledge Internet (CNKI) up to March 22, 2016. RESULTS: A total of 20 studies including 8,201 cases and 9,294 controls were included in this meta-analysis. Four of 20 studies related to the hepatocellular carcinoma risk. When all the eligible studies were pooled into this meta-analysis, a significant association between miR-149 gene rs2292832 polymorphism and hepatocellular carcinoma risk was found. While no association was found between this gene polymorphism and overall cancer risk. CONCLUSIONS: Our meta-analysis supports that the miR-149 gene rs2292832 polymorphism contributed to the risk of hepatocellular carcinoma from currently available evidence. However, a study with a larger sample size is needed to further evaluate gene-environment interaction on MiR-149 gene rs2292832 polymorphism and hepatocellular carcinoma risk.

17.
Minerva Med ; 107(4): 259-69, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27348444

RESUMEN

INTRODUCTION: Single nucleotide polymorphism in miRNAs can alter its expression, thus can lead to the development of cancers. Numerous studies have explored the association between MIR-149 gene rs2292832 polymorphism and hepatocellular carcinoma (HCC) risk, but the results remains inconsistent. So, we performed this pooled analyses in order to get a precise result. EVIDENCE ACQUISITION: Odds ratios (OR) with 95% confidence intervals (CI), calculated by STATA software, was used to determine whether MIR-149 gene rs2292832 polymorphism contributes to the risk of HCC. A comprehensive literature search was conducted on Medline (mainly PubMed), Cochrane Library database, Web of science and the China National Knowledge Internet (CNKI) up to March 22, 2016. EVIDENCE SYNTHESIS: A total of 19 studies including 8201 cases and 9294 controls were included in this meta-analysis. Four of 20 studies related to the HCC risk. When all the eligible studies were pooled into this meta-analysis, a significant association between MIR-149 gene rs2292832 polymorphism and hepatocellular carcinoma risk was found, while no association was found between this gene polymorphism and overall cancer risk. CONCLUSIONS: Our meta-analysis supports that the MIR-149 gene rs2292832 polymorphism contributed to the risk of HCC from currently available evidence. However, a study with a larger sample size is needed to further evaluate gene-environment interaction on MIR-149 gene rs2292832 polymorphism and HCC risk.


Asunto(s)
Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/genética , MicroARNs/genética , Polimorfismo de Nucleótido Simple , Humanos , Neoplasias/epidemiología , Neoplasias/genética , Factores de Riesgo
18.
Asian Pac J Trop Med ; 9(8): 796-800, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27569891

RESUMEN

OBJECTIVE: To study the effect of hGC-MSCs from human gastric cancer tissue on cell proliferation, invasion and epithelial-mesenchymal transition in tumor tissue of gastric cancer tumor-bearing mice. METHODS: BABL/c nude mice were selected as experimental animals and gastric cancer tumor-bearing mice model were established by subcutaneous injection of gastric cancer cells, randomly divided into different intervention groups. hGC-MSCs group were given different amounts of gastric cancer cells for subcutaneous injection, PBS group was given equal volume of PBS for subcutaneous injection. Then tumor tissue volume were determined, tumor-bearing mice were killed and tumor tissues were collected, mRNA expression of proliferation, invasion, EMT-related molecules were determined. RESULTS: 4, 8, 12, 16, 20 d after intervention, tumor tissue volume of hGC-MSCs group were significantly higher than those of PBS group and the more the number of hGC-MSCs, the higher the tumor tissue volume; mRNA contents of Ki-67, PCNA, Bcl-2, MMP-2, MMP-7, MMP-9, MMP-14, N-cadherin, vimentin, Snail and Twist in tumor tissue of hGC-MSCs group were higher than those of PBS group, and mRNA contents of Bax, TIMP1, TIMP2 and E-cadherin were lower than those of PBS group. CONCLUSION: hGC-MSCs from human gastric cancer tissue can promote the tumor growth in gastric cancer tumor-bearing mice, and the molecular mechanism includes promoting cell proliferation, invasion and epithelial-mesenchymal transition.

19.
Int J Infect Dis ; 42: 34-39, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26523640

RESUMEN

BACKGROUND: A Chinese medical team managed Ebola virus disease (EVD) patients in Sierra Leone from October 2014 to March 2015 and attended to 693 suspected patients, of whom 288 had confirmed disease. METHODS: A retrospective study was conducted of the 288 patients with confirmed disease. Clinical symptoms, manifestations, and serum viral load were analyzed and compared among the different groups for mortality and survival time. RESULTS: Among the 288 confirmed EVD patients (149 male and 139 female, median age 28 years, and median log viral load 6.68), 98 died, 36 recovered, and 154 were lost to follow-up. Common symptoms were fever (77.78%), fatigue (64.93%), abdominal pain (64.58%), headache (62.85%), and diarrhea (61.81%). Compared to patients aged<18 years, those who were older than 40 years had a higher probability of death (odds ratio 2.855, p=0.044). Patients with a viral load of >10(6) copies/ml had a higher case fatality rate than those with <10(6) copies/ml (odds ratio 3.095, p=0.004). Cox regression showed that age, viral load, and the presence of diarrhea correlated with mortality. CONCLUSION: Patients with a high viral load, of older age, and with diarrhea had a higher mortality and shorter survival time.


Asunto(s)
Fiebre Hemorrágica Ebola/mortalidad , Carga Viral , Adulto , Factores de Edad , Anciano , Diarrea/virología , Ebolavirus/aislamiento & purificación , Femenino , Fiebre Hemorrágica Ebola/virología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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