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1.
Molecules ; 28(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37110853

RESUMO

Ionic liquids (ILs) have arisen as alternatives to organic solvents and been used in natural pigment extraction in recent decades. However, the solubility and stability of carotenoids in phosphonium- and ammonium-based ILs are insufficiently explored. In this work, the physicochemical properties of the ILs, and the dissolution behavior and storage stability of three carotenoids (astaxanthin, ß-carotene, and lutein) in the IL aqueous solution were investigated. The results showed that the solubility of the carotenoids in the acidic IL solution is higher than that in the alkaline IL solution, and the optimal pH is about 6. The solubility of astaxanthin (40 mg/100 g), ß-carotene (105 mg/100 g), and lutein (5250 mg/100 g) was the highest in tributyloctylphosphonium chloride ([P4448]Cl) due to the van der Waals forces with [P4448]+ and hydrogen bonding with Cl-. A high temperature was beneficial to improve the solubility, but it can reduce the storage stability. Water has no significant effect on the carotenoid stability, but a high water content decreases the carotenoid solubility. A IL water content of 10-20%, an extraction temperature of 338.15 K, and a storage temperature of less than 298.15 K are beneficial for reducing the IL viscosity, improving carotenoid solubility, and maintaining good stability. Moreover, a linear correlation was found between the color parameters and carotenoid contents. This study provides some guidance for screening suitable solvents for carotenoid extraction and storage.

2.
Int J Biol Macromol ; 240: 124406, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060976

RESUMO

Surgical resection of osteosarcoma is always accompanied by residual metastasis of tumor cells and bone tissue defects. In this work, a novel kind of gelatin/polylactic acid (PLA) coaxial fiber membrane with a shell layer containing doxorubicin-loaded hydroxyapatite (DOX@nHAp) nanoparticles and a core layer containing Icariin (ICA) was developed for antitumor and bone enhancement at the defect site. Physical evaluation displayed that the composite membrane provided moderate hydrophilicity, enhanced tensile strength (Dry: 2-3 MPa, wet: 1-2 MPa) and elasticity (70-100 %), as well as increased specific surface area and pore volume (19.39 m2/g and 0.16 cm3/g). In SBF, DOX@nHAp in the fibers promoted biomineralization on the fiber surface. In in vitro evaluation, approximately 80 % of DOX had a short-term release during the first 8 days, followed by long-term release behavior of ICA for up to 40 days. CCK-8 results confirmed that the membrane could actively support MC3T3-E1 cells proliferation and was conductive to high alkaline phosphatase expression, while the viability of MG-63 cells was effectively inhibited to 50 %. Thus, the dual-loaded fibrous membrane with a coaxial structure and nHAp is a promising system for anticancer and defects reconstruction after osteosarcoma surgery.


Assuntos
Gelatina , Osteossarcoma , Humanos , Gelatina/química , Durapatita , Alicerces Teciduais/química , Poliésteres/química , Osso e Ossos , Doxorrubicina/farmacologia , Osteossarcoma/tratamento farmacológico
3.
ACS Biomater Sci Eng ; 9(4): 1976-1990, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36881921

RESUMO

In this study, we developed a poly(ß-amino ester) (PBAE) hydrogel for the double release of vancomycin (VAN) and total flavonoids of Rhizoma Drynariae (TFRD). VAN was covalently bonded to PBAE polymer chains and was released to enhance the antimicrobial effect first. TFRD chitosan (CS) microspheres were physically dispersed in the scaffold, TFRD was released from the microspheres, and osteogenesis was induced subsequently. The scaffold had good porosity (90.12 ± 3.27%), and the cumulative release rate of the two drugs in PBS (pH 7.4) solution exceeded 80%. In vitro antimicrobial assays demonstrated the antibacterial properties of the scaffold against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Besides these, cell viability assays indicated that the scaffold had good biocompatibility. Moreover, alkaline phosphatase and matrix mineralization were expressed more than in the control group. Overall, cell experiments confirmed that the scaffolds have enhanced osteogenic differentiation capabilities. In conclusion, the dual-drug-loaded scaffold with antibacterial and bone regeneration effects is promising in the field of bone repair.


Assuntos
Anti-Infecciosos , Osteogênese , Staphylococcus aureus , Hidrogéis/farmacologia , Escherichia coli , Alicerces Teciduais/química , Antibacterianos/farmacologia , Antibacterianos/química , Vancomicina/farmacologia , Vancomicina/química , Anti-Infecciosos/farmacologia
4.
Foods ; 11(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36360091

RESUMO

Hydrophilic tannic acid and hydrophobic resveratrol were successfully co-encapsulated in zein nanoparticles prepared using antisolvent precipitation and then coated with pectin by electrostatic deposition. The encapsulation efficiencies of the tannic acid and resveratrol were 51.5 ± 1.9% and 77.2 ± 3.2%, respectively. The co-encapsulated nanoparticles were stable against aggregation at the investigated pH range of 2.0 to 8.0 when heated at 80 °C for 2 h and when the NaCl concentration was below 50 mM. The co-encapsulated tannic acid and resveratrol exhibited stronger in vitro antioxidant activity than ascorbic acid, as determined by 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH·) and 2,2'-azinobis (3-ethylberizothiazoline-6-sulfonic acid) radical cation (ABTS+·) scavenging assays. The polyphenols-loaded nanoparticles significantly decreased the malondialdehyde (MDA) concentration and increased the superoxide dismutase (SOD) and catalase (CAT) activities in peroxide-treated human hepatoma cells (HepG2). An in vitro digestion model was used to study the gastrointestinal fate of the nanoparticles. In the stomach, encapsulation inhibited tannic acid release, but promoted resveratrol release. However, in the small intestine, it led to a relatively high bioaccessibility of 76% and 100% for resveratrol and tannic acid, respectively. These results suggest that pectin-coated zein nanoparticles have the potential for the co-encapsulation of both polar and nonpolar nutraceuticals or drugs.

5.
J Clin Med ; 11(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36233412

RESUMO

OBJECTIVES: The objectives of this study were to identify global trends in research on cell-free deoxyribonucleic acid (cfDNA) from a bibliometric perspective and provide researchers with new research hotspots. METHODS: In all, we extracted 5038 pieces of literature from PubMed and 527 articles from the Web of Science Core Collection (WoSCC) database related to cfDNA published from 1 January 2017 to 31 December 2021. For PubMed literature, we employed co-word, biclustering, and strategic diagram analysis to describe the trends in research on cfDNA in the said five years. Then, we used VOSviewer analysis for the WoSCC database to display the trends in research on cfDNA in obstetrics and gynecology during 2017-2021. RESULTS: Strategy diagram analysis of 95 major Medical Subject Headings terms extracted from 5038 pieces of literature indicated that cfDNA sequence analysis for non-invasive prenatal and genetic testing and its application in the fields of neoplasm genetics and diagnosis is a newly emerging immature theme of cfDNA. VOSviewer analysis of 527 articles showed the global trends in research on cfDNA in obstetrics and gynecology, for example, in terms of most influential authors, institutions, countries, journals, and five research hotspots: (1) cfDNA application in prenatal screening and prenatal diagnosis, (2) cfDNA application in assisted reproductive technology, (3) cfDNA application in pre-eclampsia, DNA methylation, etc., (4) cfDNA application in placental dysfunction and fetal growth restriction, and (5) cfDNA application in fetal chromosomal abnormalities (fetal aneuploidy). CONCLUSIONS: Comprehensive visual analysis provides information regarding authors, organizations, countries/regions, journals, research hotspots, and emerging topics in the field of cfDNA for obstetrics and gynecology research. This comprehensive study could make it easier to find a partner for project development and build a network of knowledge on this emerging topic.

6.
Environ Sci Pollut Res Int ; 29(51): 77536-77552, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35680747

RESUMO

In this paper, nitric acid-modified activated carbon was used as an electrode in the electrosorption process for the removal of Co2+, Mn2+, and Ni2+ from wastewater. The effects of applied voltage, initial pH, and coexisting ions on removal efficiency were investigated. The adsorption process was evaluated by adsorption isotherm models. The results indicated that the electrosorption process was consistent with the Langmuir model, proving that the electrosorption process was a monolayer adsorption process. The maximum adsorption capacities of Co2+, Mn2+, and Ni2+ were 131.58 mg/g, 102.04 mg/g, and 103.09 mg/g. Electrochemical tests revealed that the specific capacitance of AC-HNO3 was 54.11 F/g when the scanning rate was 5 mV/s, while the specific capacitance of AC was 36.51 F/g. The Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) confirmed that the content of oxygen groups on the surface of activated carbon increased after modification, which provided more adsorption sites for electrosorption. When the selected concentration of HCl was used as the eluent, the elution efficiency of Co2+, Mn2+, and Ni2+ could reach 94.23%, 93.65%, and 90.61%. The removal efficiency could reach more than 95% after three cycles. The results of the study can be used as a reference significance for the removal of cobalt, manganese, and nickel ions from heavy metal wastewater by electrosorption.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Purificação da Água , Adsorção , Carvão Vegetal/química , Cobalto , Eletrodos , Concentração de Íons de Hidrogênio , Íons , Cinética , Manganês , Níquel/química , Ácido Nítrico , Oxigênio , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Técnicas Eletroquímicas
7.
8.
RSC Adv ; 12(16): 9524-9533, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35424939

RESUMO

The incidence of articular cartilage defects is increasing year by year. In order to repair the cartilage tissue at the defect, scaffolds with nanofiber structure and biocompatibility have become a research hotspot. In this study, we designed and fabricated a bi-layer scaffold prepared from an upper layer of drug-dispersed gelatin methacrylate (GELMA) hydrogel and a lower layer of a drug-encapsulated coaxial fiber scaffold prepared from silk fiber (SF) and polylactic acid (PLA). These bi-layer scaffolds have porosity (91.26 ± 3.94%) sufficient to support material exchange and pore size suitable for cell culture and infiltration, as well as mechanical properties (2.65 ± 0.31 MPa) that meet the requirements of cartilage tissue engineering. The coaxial fiber structure exhibited excellent drug release properties, maintaining drug release for 14 days in PBS. In vitro experiments indicated that the scaffolds were not toxic to cells and were amenable to chondrocyte migration. Notably, the growth of cells in a bi-layer scaffold presented two states. In the hydrogel layer, cells grow through interconnected pores and take on a connective tissue-like shape. In the coaxial fiber layer, cells grow on the surface of the coaxial fiber mats and appeared tablet-like. This is similar to the structure of the functional partitions of natural cartilage tissue. Together, the bi-layer scaffold can play a positive role in cartilage regeneration, which could be a potential therapeutic choice to solve the current problems of clinical cartilage repair.

9.
Antioxidants (Basel) ; 10(10)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34679641

RESUMO

Doxorubicin (Dox) is an effective anthracycline anticancer drug. However, recent studies have revealed that Dox resistance is a highly critical issue, and a significant reason for treatment failure. Baicalin is a flavonoid component in the roots of Scutellaria baicalensis Georgi; however, whether baicalin can increase chemosensitivity in breast cancers is still unclear. In this study, we found that cellular apoptosis occurs when excessive intracellular ROS is generated, triggered by the dual intervention of baicalin and doxorubicin, which increases intracellular calcium [Ca2+]i concentrations. Increased [Ca2+]i concentrations decrease the mitochondrial membrane potential (△Ψm), thereby causing cellular apoptosis. Pretreatment with NAC (ROS inhibitor) or BATBA (Ca2+ chelator) reduces baicalin-induced chemosensitivity. The findings of this study demonstrate that the effect of baicalin on Dox treatment could enhance cytotoxicity toward breast cancer cells via the ROS/[Ca2+]i-mediated intrinsic apoptosis pathway-thus potentially lessening the required dosage of doxorubicin, and further exploring associated mechanisms in combined treatments for breast cancer clinical interventions in the future.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33535507

RESUMO

BACKGROUND: Cisplatin administration may induce muscle atrophy, thereby reducing the fitness level of patients with head and neck cancer (HNC). To date, only animal studies have been conducted to test the effectiveness of exercise interventions in diminishing side effects of cisplatin. AIM: To determine whether exercise training improves physical fitness and health-related quality of life (HRQoL) in patients receiving chemotherapy for Head & Neck (H&N). MATERIAL AND METHODS: This pilot-randomized controlled trial was conducted on 57 participants receiving chemotherapy for HNC. The participants were randomized into an exercise group and a control group. The exercise group received moderate-intensity combined aerobic, resistance and flexibility exercises three times a week for eight weeks during chemotherapy. The control group received no specific information regarding exercise. The outcome measures including body composition, muscle strength, balance, flexibility, cardiovascular fitness and health-related quality of life (HRQoL) were assessed at baseline and eight weeks following baseline. RESULTS: The body composition (body fat percentage, p = 0.002; skeletal muscle percentage, p = 0.008), dynamic balance (p = 0.01), muscle strength (upper extremity, p = 0.037; lower extremity, p = 0.025) and HRQoL (p = 0.001) showed a significant difference between the exercise group and the control group eight weeks following baseline. Significant deteriorations were noted in flexibility, muscle strength, cardiovascular fitness and several domains of HRQoL scale in the control group at eight weeks following baseline. CONCLUSIONS: This study found that a combined aerobic, resistance and flexibility exercise program during chemotherapy may improve physical fitness (i.e., muscle strength, balance, flexibility and body composition) and HRQoL and alleviate the deterioration of cardiovascular fitness in patients with HNC. Further research studies with large sample sizes are warranted to investigate the long-term effects of exercise in this population.


Assuntos
Neoplasias de Cabeça e Pescoço , Treinamento Resistido , Exercício Físico , Terapia por Exercício , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Força Muscular , Aptidão Física , Projetos Piloto , Qualidade de Vida
11.
Bioresour Technol ; 320(Pt B): 124425, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33242687

RESUMO

The aim of this study was to explore the contribution of microbial community to cellulose degradation during cellulosic wastes composting. Three raw materials with different cellulose content were employed, including rice straws (RS), leaves (L) and mushroom dregs (MD). The cellulose degraded by 92.09%, 56.68% and 40.03% during RS, L and MD composting, respectively, which could be explained by cellulases activity. Besides, each cellulase were only linked to a specific group of bacteria, thus cellulose degradation needed the cooperation of various microorganisms. Ultimately, structural equation models verified that the richness and evenness of microbial community were the primary driving factors of cellulose degradation. The richness symbolized microbial functionality, which was equivalent to the "quality" of microbial species. The evenness symbolized the scope of function, which was equivalent to the "quantity". Therefore, the "quality" and "quantity" of microbial species drove cellulose degradation during RS, L and MD composting.


Assuntos
Celulase , Compostagem , Bactérias , Celulose , Solo
12.
Bioresour Technol ; 319: 124142, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32987278

RESUMO

This study investigated oxytetracycline (OTC) effects on nitrogen (N) transformation and bacterial community diversity during chicken manure composting. The addition of OTC inhibited nitrifying bacteria, resulted in a decrease in the transformation of NH4+-N to NO3--N during composting, and affected in the order T3 (32.76%) > T2 (28.76%) > T1 (17.02%) > CK. The OTC could act as an inhibitor against core microbial growth, leading to a delay effect during composting. 16S rRNA sequencing was employed for the functional prediction, and results indicated the bacterial community related to N transformation reconstructed under OTC stress. The core microorganisms were changed after OTC addition, with the emergence of Bacillus and Thermobifida, which could inhibit the N transformation by network analysis. Therefore, core microorganisms could be regulated to reduce the negative of OTC impacts on N transformation and thus reduce N loss during composting.


Assuntos
Compostagem , Microbiota , Oxitetraciclina , Animais , Esterco , Nitrogênio , RNA Ribossômico 16S/genética , Solo
13.
Small ; 16(41): e2001905, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32954654

RESUMO

Transition metal chalcogenides with high theoretical capacity are promising conversion-type anode materials for sodium ion batteries (SIBs), but often suffer from unsatisfied cycling stability (hundreds of cycles) caused by structural collapse and agglomerate. Herein, a rational strategy of tunable surface selenization on highly crystalline MoO2 -based carbon substrate is designed, where the sheet-like MoSe2 can be coated on the surface of bundle-like N-doped carbon/granular MoO2 substrate, realizing partial transformation from MoO2 to MoSe2 , and creating b-NC/g-MoO2 @s-MoSe2 -10 with robust hierarchical MoO2 @MoSe2 heterostructures and strong chemical couplings (MoC and MoN). Such well-designed architecture can provide signally improved reaction kinetics and reinforced structural integrity for fast and stable sodium-ion storage, as confirmed by the ex situ results and kinetic analyses as well as the density functional theory calculations. As expected, the b-NC/g-MoO2 @s-MoSe2 -10 delivers splendid rate capability and ultralong cycling stability (254.2 mAh g-1 reversible capacity at 5.0 A g-1 after 6000 cycles with ≈89.0% capacity retention). Therefore, the tunable surface strategy can provide new insights for designing and constructing heterostructures of transition metal chalcogenides toward high-performance SIBs.

14.
Sci Total Environ ; 652: 729-735, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30380480

RESUMO

Few studies have investigated the spatial variation in road traffic indicators associated with lung cancer risk. The purpose of this study was to explore the relationship between road traffic-related indicators and lung cancer risk and to estimate its spatial variability. The population-based case control study was conducted, including all the newly diagnosed lung cancer patients (cases) and colorectal cancer patients (controls) in Jiading District, Shanghai from 2014 to 2016. Traffic intensity variable (traffic intensity in a 500 m buffer), residential distance to major road or highway, and greenness exposure at the residence were estimated for each individual. We conducted unconditional logistic regression with adjustment for age, sex, smoking status and NDVI values and geographically weighted logistic regression (GWLR). The clustering of lung cancer risk was analyzed by Bernoulli model of the SaTScan software. This study included 1461 lung cancer patients and 954 colorectal cancer patients. In multivariate logistic regression, smoking [OR 1.25 95% CI (1.15-1.35)], living <50 m from the major road [OR 1.43 95% CI (1.02-2.03)] were significantly associated with lung cancer risk. Residential Proximity to highway, residential greenness, and traffic intensity were not significantly associated with lung cancer risk. The GWLR model showed that the degree of correlation between residential proximity to major road and lung cancer risk varied geographically. The SaTScan results showed a lung cancer cluster in the southwest of Jiading District, Shanghai. Our study suggested that the distance from residence to the main road was significantly associated with lung cancer risk, which varied geographically. It is helpful to further study the traffic factors' spatial variation related to lung cancer risk and carry out reasonable regional planning.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Neoplasias Pulmonares/epidemiologia , Adulto , Idoso , China/epidemiologia , Feminino , Geografia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Características de Residência , Fatores de Risco , Emissões de Veículos/análise
15.
J Immunol Res ; 2018: 6989717, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30057918

RESUMO

OBJECTIVE: To explore the association between infections with HIV and Schistosoma japonicum, and to determine the influences of the HIV-S. japonicum coinfections on the immune system of Yi people. METHODS: A block design study was conducted in a Yi county in southwestern China, one of the endemic areas of both HIV/AIDS and S. japonicum in China. All participants were screened for HIV antibodies and S. japonicum antibodies (SjAb) and were classified into four groups: HIV(+)/S. japonicum(-), HIV(-)/S. japonicum (+), HIV(+)/S. japonicum(+), and HIV(-)/S. japonicum(-). RESULTS: There were significant differences among the four groups in both CD4+ T lymphocytes and CD8+ T lymphocytes, but no significant difference in CD3+ T lymphocytes. Both the CD4+ T lymphocyte counts and the ratio of CD4+/CD8+ were lower in HIV-infected people compared with those uninfected. People infected with S. japonicum had increased CD4+ T lymphocyte counts but reduced CD8+ T lymphocyte counts. Similarly, the ratio of CD4+/CD8+ was higher in S. japonicum-infected people compared with those uninfected. People coinfected with HIV and S. japonicum had lower CD4+ T lymphocyte counts, lower ratio of CD4+/CD8+, and higher CD8+ T lymphocyte counts compared with those infected with HIV only or S. japonicum only. People infected with HIV only and those coinfected with HIV and S. japonicum had a higher level of IFN-γ compared with people with no infection. There were no significant differences between people infected with HIV only and with S. japonicum only in the levels of IFN-γ and IL-10. CONCLUSIONS: People coinfected with HIV and S. japonicum might have a suppressed immune function because of a decrease in CD4+ T lymphocyte counts, a lowered ratio of CD4+/CD8+, and an increase in CD8+ T lymphocyte counts. Coinfection with HIV and S. japonicum would alter the level of IFN-γ in plasma.


Assuntos
Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Infecções por HIV/imunologia , HIV/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Adolescente , Adulto , Animais , Anticorpos Anti-Helmínticos/sangue , Anticorpos Antivirais/sangue , China , Coinfecção , Feminino , Humanos , Interferon gama/metabolismo , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Artigo em Inglês | MEDLINE | ID: mdl-29933638

RESUMO

BACKGROUND: Schistosomiasis is one of the most devastating tropical diseases in the world. Oncomelania hupensis is the only intermediate host of Schistosoma japonicum, and its growth and development are sensitive to environmental factors. The Three Gorges Dam has substantially altered the water level in the Yangtze River. This study focused on the impact of the flooding time on the occurrence of Oncomelania snails in Hunan Province, China. METHODS: The data regarding Oncomelania snails were collected from the Schistosomiasis Atlas of the People's Republic of China. Air temperature, hours of daylight and relative humidity from 1995 to 2002 were collected from the China Meteorological Data Sharing Service System. The data for rainfall and days inundated with water were collected from the Hunan flood control information system and hydrological stations in Hunan Province. A generalized additive model was used to estimate the impact of these factors on the presence or absence of snails. RESULTS: The number of days inundated with water in the areas with snails ranged from 56 to 212 days. However, 82 percent of the areas without snails were inundated with water less than 60 days. The lowest air temperature in a year in the areas without snails ranges from -2.88 °C to -2.10 °C, and the range was from -2.88 °C to -2.34 °C for areas with snails. Annual rainfall in the areas with snails ranged from 989 to 1565 mm, and the range was from 1230 mm to 1647 mm for the areas without snails. The results from the generalized additive model showed that the number of days inundated with water, lowest air temperature in a year, annual rainfall, days of daily rainfall greater than 0.1 mm, and hours of daylight were the factors that significantly affect the occurrence of snails in Hunan Province, China. CONCLUSIONS: The number of days inundated with water may be a key factor determining the geographical distribution of Oncomelania snails in Hunan Province and the favorable number of days inundated with water for the survival of snails ranges from about 2 to 7 months.


Assuntos
Reservatórios de Doenças/parasitologia , Inundações , Rios/parasitologia , Esquistossomose Japônica/epidemiologia , Esquistossomose Japônica/transmissão , Caramujos/parasitologia , Animais , China/epidemiologia , Caramujos/crescimento & desenvolvimento
17.
PLoS Negl Trop Dis ; 12(5): e0006548, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29813073

RESUMO

BACKGROUND: Schistosomiasis is a snail-borne parasitic disease and is endemic in many tropical and subtropical countries. Biomphalaria straminea, an intermediate host for Schistosoma mansoni, is native to the southeastern part of South America and has established in other regions of South America, Central America and southern China during the last decades. S. mansoni is endemic in Africa, the Middle East, South America and the Caribbean. Knowledge of the potential global distribution of this snail is essential for risk assessment, monitoring, disease prevention and control. METHODS AND FINDINGS: A comprehensive database of cross-continental occurrence for B. straminea was compiled to construct ecological models. We used several approaches to investigate the distribution of B. straminea, including direct comparison of climatic conditions, principal component analysis and niche overlap analyses to detect niche shifts. We also investigated the impacts of bioclimatic and human factors, and then used the bioclimatic and footprint layers to predict the potential distribution of B. straminea at global scale. We detected niche shifts accompanying the invasions of B. straminea in the Americas and China. The introduced populations had enlarged its habitats to subtropical regions where annual mean temperature is relatively low. Annual mean temperature, isothermality and temperature seasonality were identified as most important climatic features for the occurrence of B. straminea. Additionally, human factors improved the model prediction (P<0.001). Our model showed that under current climate conditions the snail should mostly be confined to the tropic and subtropic regions, including South America, Central America, Sub-Saharan Africa and Southeast Asia. CONCLUSIONS: Our results confirmed that niche shifts took place in the invasions of B. straminea, in which bioclimatic and human factors played an important role. Our model predicted the global distribution of B. straminea based on habitat suitability, which would help for prioritizing monitoring and management efforts for B. straminea control in the context of ongoing climate change and human disturbances.


Assuntos
Schistosoma mansoni/fisiologia , Esquistossomose mansoni/parasitologia , África/epidemiologia , Animais , Ásia/epidemiologia , Biomphalaria/parasitologia , Vetores de Doenças , Humanos , Schistosoma mansoni/genética , Schistosoma mansoni/isolamento & purificação , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/transmissão , América do Sul/epidemiologia
18.
Parasit Vectors ; 11(1): 183, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29540206

RESUMO

BACKGROUND: Schistosomiasis remains a major public health concern in China. Oncomelania hupensis (O. hupensis) is the sole intermediate host of Schistosoma japonicum, and its change in distribution and density influences the endemic S. japonicum. The Three Gorges Dam (TGD) has substantially changed the downstream water levels of the dam. This study investigated the quantitative relationship between flooding duration and the density of the snail population. METHODS: Two bottomlands without any control measures for snails were selected in Yueyang City, Hunan Province. Data for the density of the snail population and water level in both spring and autumn were collected for the period 2009-2015. Polynomial regression analysis was applied to explore the relationship between flooding duration and the density of the snail population. RESULTS: Data showed a convex relationship between spring snail density and flooding duration of the previous year (adjusted R2, aR2 = 0.61). The spring snail density remained low when the flooding duration was fewer than 50 days in the previous year, was the highest when the flooding duration was 123 days, and decreased thereafter. There was a similar convex relationship between autumn snail density and flooding duration of the current year (aR2 = 0.77). The snail density was low when the flooding duration was fewer than 50 days and was the highest when the flooding duration was 139 days. CONCLUSIONS: There was a convex relationship between flooding duration and the spring or autumn snail density. The snail density was the highest when flooding lasted about four to 5 months.


Assuntos
Reservatórios de Doenças/parasitologia , Inundações , Modelos Estatísticos , Esquistossomose Japônica/epidemiologia , Caramujos/parasitologia , Abastecimento de Água , Animais , Ecossistema , Humanos , Lagos/parasitologia , População , Análise de Regressão , Esquistossomose Japônica/parasitologia , Esquistossomose Japônica/prevenção & controle , Esquistossomose Japônica/transmissão , Estações do Ano
19.
Vaccine ; 35(46): 6275-6282, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28987442

RESUMO

BACKGROUND: Haemophilus influenzae type b (Hib) is an important cause of invasive bacterial disease in children worldwide. The limited awareness of disease burden is a major barrier to the introduction of Hib vaccine into China's National Immunization Program. Therefore, we conducted a systematic review and meta-analysis to estimate carriage of Hib and burden of its related diseases in Chinese children. METHODS: We systematically searched Pubmed, Web of Science, Ovid, Chinese National Knowledge Infrastructure (CNKI), and Wanfang databases for studies published up to December 31, 2016, reporting Hib carriage and burden of Hib diseases among children in Mainland China. Pooled estimates were obtained using random-effects models. RESULTS: We included 27 studies with 15783 children across 14 provinces. The pooled carriage of Hib was 5.87% (95% CI 3.42-8.33) for healthy children. The pooled proportion of disease due to Hib were 4.06% (95% CI 3.29-4.83) for acute lower respiratory tract infection (ALRI) and 27.32% (95% CI 0.41-54.24) for bacterial meningitis. The proportion of ALRI caused by Hib was higher in northern China than that in the south. Significant heterogeneity was noted across and within regions (P<0.001). After the induction of Hib vaccine, meta-regression showed that carriage of Hib changed little (P=0.725), but the proportion of ALRI caused by Hib in children decreased (P<0.001). CONCLUSIONS: Hib carriage persists at low levels among children in China. The proportion of ALRI due to Hib infection decreased with year. Incorporation of Hib vaccine into the National Immunization Program could reduce the burden of Hib disease in China.


Assuntos
Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Haemophilus influenzae tipo b/isolamento & purificação , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência
20.
BMJ Open ; 7(8): e015717, 2017 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-28801405

RESUMO

OBJECTIVES: Hepatitis C virus (HCV) infection is a major public health problem in southwestern China. Our aim of the study was to assess the prevalence of HCV infection and its correlates in the Yi population of this region. METHODS: A community-based survey was conducted to investigate sociodemographic characteristics and other associated factors for HCV infection in a rural area of southwestern China. Blood samples were collected and tested for antibodies to HCV. Anti-HCV positive samples were further assessed for HCV RNA. RESULTS: A total of 2558 participants aged ≥14 years were included in our analysis. Of them, 2.8% (95% CI 2.2% to 3.5%) were positive for HCV antibody. Multiple logistic regression analysis revealed that sex (male vs female: adjusted OR (aOR)=3.30, 95% CI 1.80 to 6.07), marital status (unmarried vs married: aOR=0.27, 95% CI 0.09 to 0.80), ever using injection drug (aOR=28.65, 95% CI 15.9 to 51.64) and ever having blood transfusion (aOR=7.64, 95% CI 1.94 to 30.16) were significantly associated with HCV infection (indicated by positive HCV antibody). Stratified analysis by HIV infection found that in HIV-negative individuals, sex (male vs female: aOR=3.84, 95% CI 1.88 to 7.85), ever using injection drug (aOR=22.15, 95% CI 8.45 to 58.04), having multiple sexual partners (aOR=2.57, 95% CI 1.26 to 5.23), and ever having blood transfusion (aOR=16.54, 95% CI 4.44 to 61.58) were significantly associated with HCV infection and in HIV-positive individuals, ever using injection drug (aOR=8.96, 95% CI 3.16 to 25.38) was associated with HCV infection. CONCLUSION: The data suggested a higher risk of HCV infection in this area when compared with the rest of China and some unique associated factors. Rapid scale-up of targeted interventions are needed to prevent further transmission and consequent morbidities.


Assuntos
Infecções por HIV/complicações , Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/etnologia , Adolescente , Adulto , Distribuição por Idade , China/epidemiologia , Estudos Transversais , Etnicidade , Feminino , Hepacivirus , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , População Rural , Distribuição por Sexo , Adulto Jovem
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