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1.
Insights Imaging ; 14(1): 74, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37121955

RESUMO

OBJECTIVES: To evaluate the performance of a dual-energy computed tomography (DECT) virtual non-calcium (VNCa) technique in the detection of edema-like marrow signal intensity (ELMSI) in patients with knee joint osteoarthritis (OA) compared to magnetic resonance imaging (MRI). METHODS: The study received local ethics board approval, and written informed consent was obtained. DECT and MRI were used to examine 28 knees in 24 patients with OA. VNCa images were generated by dual-energy subtraction of calcium. The knee joint was divided into 15 regions for ELMSI grading, performed independently by two musculoskeletal radiologists, with MRI as the reference standard. We also analyzed CT numbers through receiver operating characteristics and calculated cut-off values. RESULTS: For the qualitative analysis, we obtained CT sensitivity (Readers 1, 2 = 83.7%, 89.8%), specificity (Readers 1, 2 = 99.5%, 99.5%), positive predictive value (Readers 1, 2 = 95.3%, 95.7%), and negative predictive value (Readers 1, 2 = 97.9%, 98.7%) for ELMSI. The interobserver agreement was excellent (κ = 0.92). The area under the curve for Reader 1 and Reader 2 was 0.961 (95% CI 0.93, 0.99) and 0.992 (95% CI 0.98, 1.00), respectively. CT numbers obtained from the VNCa images were significantly different between regions with and without ELMSI (p < .001). CONCLUSIONS: VNCa images have good diagnostic performance for the qualitative and quantitative analysis of knee osteoarthritis-related ELMSI.

2.
J Interpers Violence ; 37(11-12): NP8405-NP8429, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33280489

RESUMO

This cross-sectional study sought to broaden the limited evidence on violence against young adolescent girls in non-conflict zones within the Democratic Republic of the Congo (DRC). Our goal was to estimate the prevalence of and the predictors of physical and/or sexual abuse among girls aged 11-18 years in Kinshasa. A total of 3,100 girls from five randomly selected schools were recruited by our team and given the questionnaires; among them, 3,011 (97.1%) participants completed the questionnaires and were included in the study for further analysis. After collecting all valid responses, the overall prevalence of physical and/or sexual abuse was sorted into the following categories: experienced physical abuse without a weapon (recorded by 70.1% of respondents), experienced physical abuse with a weapon (66.3% of respondents), attempted rape without penetration (76.5% of respondents), experienced attempted rape with penetration (73.9% of respondents), and experienced verbal sexual harassment (93.0%).Our logistic regression analysis indicated that specific kinds of living arrangements (such as only living with the father, mother, or a caregiver; odds ratio ranged 1.8 to 6.9) and places of residence (such as living in lower-class or middle-class districts; odds ratio ranged 1.7 to 6.2) had the strongest associations with higher risk pertaining to whether the respondent had experienced physical and/or sexual abuse in the past. Meanwhile, factors such as the students' level of education (both middle grade and upper grade) and occupation of the father (specifically whether holding a part-time job or retired) were deemed to be more protective. However, physical and/or sexual abuse prevalence was found to be high among middle school girls in Kinshasa. Therefore, we recommend that drastic policies and strategies aimed at socioeconomic issue and living condition ameliorations among families should be implemented to curtail physical and sexual abuse in the nonconflict zones of the DRC.


Assuntos
Estupro , Adolescente , Estudos Transversais , República Democrática do Congo/epidemiologia , Feminino , Humanos , Prevalência , Fatores de Risco , Estudantes , Inquéritos e Questionários
3.
Mol Genet Genomic Med ; 9(8): e1731, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34212515

RESUMO

BACKGROUND: Bardet-Biedl syndrome (BBS) is a rare and genetically heterogeneous disease with a broad spectrum of clinical features, including but not limited to rod-cone dystrophy, postaxial polydactyly, central obesity, intellectual disability, hypogonadism, and renal dysfunction. Twenty-one BBS (Bardet-Biedl syndrome) genes have been identified to date. There is minimal mutation information on BBS in Chinese populations and the exact pathogenic mechanism of the null mutation of BBS9 remains unknown. METHODS: A patient from a Chinese consanguineous family presented with polydactyly, truncal obesity, intellectual disability, genital anomaly, and retinitis pigmentosa was analyzed in this study. Blood DNA and RNA were extracted from the blood of the proband and the parents. The proband was screened for mutations by whole-exome sequencing. The likely pathogenic mutation detected in the proband was further confirmed by the Sanger sequence in the family. Real-time RT-PCR was used to measure the expression of BBS9 in the proband and the control. RESULTS: Targeted exome sequencing identified a novel homozygous null mutation (NM_198428.3: c.445C>T) in the 6th exon of the BBS9 gene in the proband and Sanger sequencing was used to validate the heterozygosity in the parents. The mutation was validated to induce the nonsense-mediated decay of BBS9 messenger RNAs by real-time RT-PCR. CONCLUSIONS: The molecular findings helped to explain the clinical manifestations. The novel homozygous pathogenic variation expanded the mutational spectrum of the BBS9 gene in the Chinese population and will help to understand the pathogenic mechanism of BBS9 null mutation.


Assuntos
Síndrome de Bardet-Biedl/genética , Proteínas do Citoesqueleto/genética , Adolescente , Síndrome de Bardet-Biedl/diagnóstico , Células Cultivadas , Consanguinidade , Proteínas do Citoesqueleto/metabolismo , Homozigoto , Humanos , Mutação com Perda de Função , Masculino , Degradação do RNAm Mediada por Códon sem Sentido
4.
Hum Vaccin Immunother ; 17(11): 4406-4411, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34324411

RESUMO

The objective of this study was to investigate the parent cognition of information regarding the human papillomavirus (HPV) and their willingness toward HPV vaccination of their middle-school-aged children in Zunyi, Guizhou Province, China.The results provide a basis for improving the awareness concerning HPV-related information as a key vaccination strategy for implementing the HPV vaccine in the local context. Methods include the random cluster sampling method and questionnaires to survey parents. General descriptive and single-factor analyses were used to assess cognition to determine factors influencing vaccine willingness. Of 1,074 parents, 28.2% (302) and 38.0% (408) had heard of HPV and its vaccine before the survey, and when given HPV-related information, 73.9% (794) parents were willing to vaccinate their children. Reasons why parents did or did not want the vaccination were surveyed, with lack of sufficient knowledge about HPV and its vaccine being the primary reason to refuse vaccination. Concerns about safety, effectiveness, and perceiving low risk are the biggest obstacle in promoting vaccination. When the price is <1000, most parents (56.1%) are willing to vaccinate their children; thus, cost is also one of the concerns. Therefore, strategies for improving public awareness regarding the risk of cervical cancer and confidence in vaccination must be considered by policymakers.If the national authority confirms that the vaccine is safe and effective, the vaccine should be included in the national immunization program to increase publicity, address safety concerns, and allow for price regulation.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Criança , China , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Papillomaviridae , Infecções por Papillomavirus/prevenção & controle , Pais , Aceitação pelo Paciente de Cuidados de Saúde , Instituições Acadêmicas , Estudantes , Inquéritos e Questionários , Vacinação
5.
ISME J ; 15(10): 3084-3093, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972726

RESUMO

Microbial corrosion of iron-based materials is a substantial economic problem. A mechanistic understanding is required to develop mitigation strategies, but previous mechanistic studies have been limited to investigations with relatively pure Fe(0), which is not a common structural material. We report here that the mechanism for microbial corrosion of stainless steel, the metal of choice for many actual applications, can be significantly different from that for Fe(0). Although H2 is often an intermediary electron carrier between the metal and microbes during Fe(0) corrosion, we found that H2 is not abiotically produced from stainless steel, making this corrosion mechanism unlikely. Geobacter sulfurreducens and Geobacter metallireducens, electrotrophs that are known to directly accept electrons from other microbes or electrodes, extracted electrons from stainless steel via direct iron-to-microbe electron transfer. Genetic modification to prevent H2 consumption did not negatively impact on stainless steel corrosion. Corrosion was inhibited when genes for outer-surface cytochromes that are key electrical contacts were deleted. These results indicate that a common model of microbial Fe(0) corrosion by hydrogenase-positive microbes, in which H2 serves as an intermediary electron carrier between the metal surface and the microbe, may not apply to the microbial corrosion of stainless steel. However, direct iron-to-microbe electron transfer is a feasible route for stainless steel corrosion.


Assuntos
Geobacter , Corrosão , Elétrons , Geobacter/genética , Ferro , Aço Inoxidável
6.
Appl Environ Microbiol ; 87(13): e0073121, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33931421

RESUMO

It is known that the physiology of Methanosarcina species can differ significantly, but the ecological impact of these differences is unclear. We recovered two strains of Methanosarcina from two different ecosystems with a similar enrichment and isolation method. Both strains had the same ability to metabolize organic substrates and participate in direct interspecies electron transfer but also had major physiological differences. Strain DH-1, which was isolated from an anaerobic digester, used H2 as an electron donor. Genome analysis indicated that it lacks an Rnf complex and conserves energy from acetate metabolism via intracellular H2 cycling. In contrast, strain DH-2, a subsurface isolate, lacks hydrogenases required for H2 uptake and cycling and has an Rnf complex for energy conservation when growing on acetate. Further analysis of the genomes of previously described isolates, as well as phylogenetic and metagenomic data on uncultured Methanosarcina in anaerobic digesters and diverse soils and sediments, revealed a physiological dichotomy that corresponded with environment of origin. The physiology of type I Methanosarcina revolves around H2 production and consumption. In contrast, type II Methanosarcina species eschew H2 and have genes for an Rnf complex and the multiheme, membrane-bound c-type cytochrome MmcA, shown to be essential for extracellular electron transfer. The distribution of Methanosarcina species in diverse environments suggests that the type I H2-based physiology is well suited for high-energy environments, like anaerobic digesters, whereas type II Rnf/cytochrome-based physiology is an adaptation to the slower, steady-state carbon and electron fluxes common in organic-poor anaerobic soils and sediments. IMPORTANCE Biogenic methane is a significant greenhouse gas, and the conversion of organic wastes to methane is an important bioenergy process. Methanosarcina species play an important role in methane production in many methanogenic soils and sediments as well as anaerobic waste digesters. The studies reported here emphasize that the genus Methanosarcina is composed of two physiologically distinct groups. This is important to recognize when interpreting the role of Methanosarcina in methanogenic environments, especially regarding H2 metabolism. Furthermore, the finding that type I Methanosarcina species predominate in environments with high rates of carbon and electron flux and that type II Methanosarcina species predominate in lower-energy environments suggests that evaluating the relative abundance of type I and type II Methanosarcina may provide further insights into rates of carbon and electron flux in methanogenic environments.


Assuntos
Methanosarcina , Acetatos/metabolismo , Anaerobiose , Reatores Biológicos , Ecossistema , Transporte de Elétrons , Etanol/metabolismo , Genoma Arqueal , Hidrogênio/metabolismo , Metano/metabolismo , Methanosarcina/genética , Methanosarcina/isolamento & purificação , Methanosarcina/metabolismo , Filogenia
7.
Biomacromolecules ; 22(3): 1305-1311, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33591727

RESUMO

Protein-based electronic biomaterials represent an attractive alternative to traditional metallic and semiconductor materials due to their environmentally benign production and purification. However, major challenges hindering further development of these materials include (1) limitations associated with processing proteins in organic solvents and (2) difficulties in forming higher-order structures or scaffolds with multilength scale control. This paper addresses both challenges, resulting in the formation of one-dimensional bundles composed of electrically conductive protein nanowires harvested from the microbes Geobacter sulfurreducens and Escherichia coli. Processing these bionanowires from common organic solvents, such as hexane, cyclohexane, and DMF, enabled the production of multilength scale structures composed of distinctly visible pili. Transmission electron microscopy revealed striking images of bundled protein nanowires up to 10 µm in length and with widths ranging from 50-500 nm (representing assembly of tens to hundreds of nanowires). Conductive atomic force microscopy confirmed the presence of an appreciable nanowire conductivity in their bundled state. These results greatly expand the possibilities for fabricating a diverse array of protein nanowire-based electronic device architectures.


Assuntos
Geobacter , Nanofios , Condutividade Elétrica , Transporte de Elétrons , Solventes
8.
Curr Med Sci ; 40(3): 510-517, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32474858

RESUMO

Women diagnosed with breast cancer may have serious psychological problems and will suffer from adjustment disorder (AjD). We investigated the prevalence of AjD in female breast cancer patients who were diagnosed within 1 year and examined the severe life events they experienced, and the most common symptoms of AjD. 342 newly diagnosed (<1 year) female breast cancer patients were recruited from Tongji Hospital and Hubei Cancer Hospital in Hubei, China, from July 2018 to May 2019. The patients completed the self-report questionnaire including demographic characteristics and the scale ADNM-20 for the diagnosis of AjD. SPSS20.0 was used for data analysis. As a result, the prevalence of AjD in breast cancer patients was 38.6%. Patients from rural areas and lacking of exercise were more likely to suffer from AjD (P<0.05). The prevalence of AjD in patients who did not regard breast cancer as the most severe life event was higher than that in patients who took breast cancer as the most severe life event (44.4% vs. 33.9%, P<0.05; OR=1.728, 95% CI=1.072-2.787). The symptom that scored highest was preoccupation (3.15). We found that the prevalence of AjD in women with breast cancer in this study is very high and warrants more attention. Patients from rural areas, lacking of exercise and subject to multiple stressors are more likely to suffer from AjD. The commonest and severe symptom is preoccupation.


Assuntos
Transtornos de Adaptação/etiologia , Transtornos de Adaptação/psicologia , Neoplasias da Mama/complicações , Neoplasias da Mama/psicologia , Adulto , Idoso , Ansiedade/etiologia , Ansiedade/psicologia , China , Feminino , Humanos , Pessoa de Meia-Idade , Prevalência , Autorrelato , Inquéritos e Questionários
9.
Ren Fail ; 41(1): 1045-1053, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31809666

RESUMO

A 43-year-old Chinese man with a silicosis history was admitted to our hospital due to bilateral lower extremity edema for 1 year, exacerbating with hematuria for 2 months. He started working as a coal miner 30 years ago, and was diagnosed as silicosis 3 months ago. Lab tests revealed hematuria 3+, proteinuria 3+, and a serum creatinine value 2.47 mg/dl on routine check. He was diagnosed with focal proliferative IgA nephropathy (IgAN) and acute tubulo-interstitial nephritis by renal biopsy. He was treated with corticosteroids and got a remission 4 months later. Immunohistochemical staining showed the deposition of macrophage receptor with collagenous structure (MARCO), nod-like receptor pyrin domain-containing-3 (NLRP3), Caspase-1, apoptosis-associated speck (ASC), interleukin (IL)-1ß, and IL-18 in both glomerular and tubulo-interstitial areas. We proposed that the silicon exposure could be related to his kidney disease in the patient and NLRP3 mediated inflammation might be involved in its pathogenesis which needs further explorations.


Assuntos
Nefropatias/etiologia , Rim/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Silicose/complicações , Adulto , Humanos , Rim/ultraestrutura , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Silicose/metabolismo
10.
mBio ; 10(4)2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31431545

RESUMO

Extracellular electron exchange in Methanosarcina species and closely related Archaea plays an important role in the global carbon cycle and enhances the speed and stability of anaerobic digestion by facilitating efficient syntrophic interactions. Here, we grew Methanosarcina acetivorans with methanol provided as the electron donor and the humic analogue, anthraquione-2,6-disulfonate (AQDS), provided as the electron acceptor when methane production was inhibited with bromoethanesulfonate. AQDS was reduced with simultaneous methane production in the absence of bromoethanesulfonate. Transcriptomics revealed that expression of the gene for the transmembrane, multiheme, c-type cytochrome MmcA was higher in AQDS-respiring cells than in cells performing methylotrophic methanogenesis. A strain in which the gene for MmcA was deleted failed to grow via AQDS reduction but grew with the conversion of methanol or acetate to methane, suggesting that MmcA has a specialized role as a conduit for extracellular electron transfer. Enhanced expression of genes for methanol conversion to methyl-coenzyme M and the Rnf complex suggested that methanol is oxidized to carbon dioxide in AQDS-respiring cells through a pathway that is similar to methyl-coenzyme M oxidation in methanogenic cells. However, during AQDS respiration the Rnf complex and reduced methanophenazine probably transfer electrons to MmcA, which functions as the terminal reductase for AQDS reduction. Extracellular electron transfer may enable the survival of methanogens in dynamic environments in which oxidized humic substances and Fe(III) oxides are intermittently available. The availability of tools for genetic manipulation of M. acetivorans makes it an excellent model microbe for evaluating c-type cytochrome-dependent extracellular electron transfer in ArchaeaIMPORTANCE The discovery of a methanogen that can conserve energy to support growth solely from the oxidation of organic carbon coupled to the reduction of an extracellular electron acceptor expands the possible environments in which methanogens might thrive. The potential importance of c-type cytochromes for extracellular electron transfer to syntrophic bacterial partners and/or Fe(III) minerals in some Archaea was previously proposed, but these studies with Methanosarcina acetivorans provide the first genetic evidence for cytochrome-based extracellular electron transfer in Archaea The results suggest parallels with Gram-negative bacteria, such as Shewanella and Geobacter species, in which multiheme outer-surface c-type cytochromes are an essential component for electrical communication with the extracellular environment. M. acetivorans offers an unprecedented opportunity to study mechanisms for energy conservation from the anaerobic oxidation of one-carbon organic compounds coupled to extracellular electron transfer in Archaea with implications not only for methanogens but possibly also for Archaea that anaerobically oxidize methane.


Assuntos
Citocromos/metabolismo , Transporte de Elétrons/fisiologia , Membranas/metabolismo , Methanosarcina/metabolismo , Acetatos/metabolismo , Antraquinonas/farmacologia , Citocromos/genética , Transporte de Elétrons/genética , Elétrons , Compostos Férricos/metabolismo , Regulação da Expressão Gênica em Archaea , Bactérias Gram-Negativas/metabolismo , Mesna/análogos & derivados , Metano/metabolismo , Metanol/metabolismo , Methanosarcina/efeitos dos fármacos , Methanosarcina/genética , Methanosarcina/crescimento & desenvolvimento , Oxirredução , Oxirredutases/metabolismo , Transcriptoma
11.
mBio ; 10(3)2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088920

RESUMO

The concept that anaerobic microorganisms can directly accept electrons from Fe(0) has been controversial because direct metal-microbe electron transfer has previously only been indirectly inferred. Fe(0) oxidation was studied with Geobacter sulfurreducens strain ACL, an autotrophic strain that was previously shown to grow with electrons derived from a graphite cathode as the sole electron donor. Strain ACL grew with Fe(0) as the sole electron donor and fumarate as the electron acceptor. However, it appeared that at least a portion of the electron transfer was via H2 produced nonenzymatically from the oxidation of Fe(0) to Fe(II). H2, which accumulated in abiotic controls, was consumed during the growth of strain ACL, the cells were predominately planktonic, and genes for the uptake hydrogenase were highly expressed. Strain ACLHF was constructed to prevent growth on H2 or formate by deleting the genes for the uptake of hydrogenase and formate dehydrogenases from strain ACL. Strain ACLHF also grew with Fe(0) as the sole electron donor, but H2 accumulated in the culture, and cells heavily colonized Fe(0) surfaces with no visible planktonic growth. Transcriptomics suggested that the outer surface c-type cytochromes OmcS and OmcZ were important during growth of strain ACLHF on Fe(0). Strain ACLHF did not grow on Fe(0) if the gene for either of these cytochromes was deleted. The specific attachment of strain ACLHF to Fe(0), coupled with requirements for known extracellular electrical contacts, suggest that direct metal-microbe electron transfer is the most likely option for Fe(0) serving as an electron donor.IMPORTANCE The anaerobic corrosion of iron structures is expensive to repair and can be a safety and environmental concern. It has been known for over 100 years that the presence of anaerobic respiratory microorganisms can accelerate iron corrosion. Multiple studies have suggested that there are sulfate reducers, methanogens, and acetogens that can directly accept electrons from Fe(0) to support sulfate or carbon dioxide reduction. However, all of the strains studied can also use H2 as an electron donor for growth, which is known to be abiotically produced from Fe(0). Furthermore, no proteins definitely shown to function as extracellular electrical contacts with Fe(0) were identified. The studies described here demonstrate that direct electron transfer from Fe(0) can support anaerobic respiration. They also map out a simple genetic approach to the study of iron corrosion mechanisms in other microorganisms. A better understanding of how microorganisms promote iron corrosion is expected to lead to the development of strategies that can help reduce adverse impacts from this process.


Assuntos
Geobacter/genética , Geobacter/metabolismo , Ferro/metabolismo , Anaerobiose , Corrosão , Citocromos/genética , Transporte de Elétrons , Formiato Desidrogenases/genética , Oxirredução , Oxirredutases/genética , Transcriptoma
12.
Huan Jing Ke Xue ; 40(4): 1849-1856, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087928

RESUMO

In order to improve the adsorption-separation of Cd2+ in water treatment, magnetic Fe3O4 coated Ca(H2PO4)2 nanoparticles (NMCDP) were developed by coprecipitation. The properties of these nanoparticles were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and magnetization curves. Experiments were carried out to investigate the effect of adsorption, reclaiming, and regeneration. The results showed that NMCDP was a stable material with a particle size of 60 nm and a saturation magnetization of 30.9 emu·g-1. The adsorption rate of Cd2+ by NMCDP was fast, and adsorption equilibrium could be achieved within 1 hour. The kinetic data were well fitted by a pseudo-second-order model, and the isotherm adsorption data agreed with the Langmuir and Freundlich model, with a maximum adsorption capacity of 142.50 mg·g-1. The adsorption capacity of Cd2+ was affected by the pH and increased when the pH was increased from 2 to 3, while with continued increase of the pH of the solution, the adsorption capacity gradually became stable. The coexisting ions in the solution had an effect on the adsorption of Cd2+, especially the divalent cation Cu2+. The NMCDP could be regenerated by using 0.01 mol·L-1 HCl and EDTA-Na2, and the results indicated that it could be recycled with a desorption rate of 68% by EDTA-Na2 solution.

13.
Small ; 14(44): e1802624, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30260563

RESUMO

Protein-based electronic materials have numerous potential advantages with respect to sustainability and biocompatibility over electronic materials that are synthesized using harsh chemical processes and/or which contain toxic components. The microorganism Geobacter sulfurreducens synthesizes electrically conductive protein nanowires (e-PNs) with high aspect ratios (3 nm × 10-30 µm) from renewable organic feedstocks. Here, the integration of G. Sulfurreducens e-PNs into poly(vinyl alcohol) (PVA) as a host polymer matrix is described. The resultant e-PN/PVA composites exhibit conductivities comparable to PVA-based composites containing synthetic nanowires. The relationship between e-PN density and conductivity of the resultant composites is consistent with percolation theory. These e-PNs confer conductivity to the composites even under extreme conditions, with the highest conductivities achieved from materials prepared at pH 1.5 and temperatures greater than 100 °C. These results demonstrate that e-PNs represent viable and sustainable nanowire compositions for the fabrication of electrically conductive composite materials.


Assuntos
Nanocompostos/química , Nanofios/química , Geobacter/metabolismo , Polímeros/metabolismo
14.
Ying Yong Sheng Tai Xue Bao ; 29(1): 93-102, 2018 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29692017

RESUMO

Trend analysis method was applied to analyze the general variation characteristics of the climate resources and meteorological disasters of growing season of the winter planting in Guangdong before (1961-1996) and after climate warming (1997-2015). Percentile method was employed to determine thresholds for extreme cold and drought in major planting regions, and the characteristics of extreme disasters since climate warming were analyzed. The results showed that, by comparing 1997-2015 with 1961-1996, the heat value in winter growing season increased significantly. The belt with a higher heat value, where the average temperature was ≥15 ℃ and accumulated temperature was ≥2200 ℃·d, covered the main winter production regions as Shaoguan, Zhanjiang, Maoming, Huizhou, Meizhou and Guangzhou. Meanwhile, the precipitation witnessed a slight increase. The regions with precipitations of 250-350 mm included Zhanjiang, Maoming, Huizhou, Guangzhou and Meizhou. Chilling injury in the winter planting season in the regions decreased, the belt with an accumulated chilling of <2 ℃·d covered the major geographic parts of the involved regions as Zhanjiang, Maoming, Guangzhou and Huizhou; and the belt with an accumulated chilling of 8-16 ℃·d covered the major geographic parts of Shaoguan and Meizhou. Meanwhile, the drought days decreased, the belt with drought days ≥50 included the major geographic parts of Zhanjiang, Maoming, Huizhou, Guangzhou and the belt with drought days <50 included the major geographic parts of Shaoguan. The typical case of the extreme disasters showed that the extreme chilling injury and drought in the main producing regions should not be overlooked. Maoming, Huizhou and Meizhou were at higher risk of extreme chilling injury, followed by Shaoguan and Guangzhou. Zhanjiang and Maoming faced the highest risk of extreme drought, Huizhou and Guangzhou took the second place, Shaoguan and Meizhou went last. During 1997-2015, the heat of winter season increased significantly, the trend of chilling and drought decreased, however, the extreme disasters occurred frequently and the risks were higher in winter production areas. It was suggested that the winter planting should be closely integrated with climate resources and the occurrence law of meteorological disasters in growing season.


Assuntos
Mudança Climática , Produção Agrícola , Desastres , China , Secas , Estações do Ano
15.
Exp Cell Res ; 361(1): 126-134, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29024700

RESUMO

Y-box binding protein-1 (YBX1) is a multifunctional protein and often acts as an indicator of poor prognosis in cancers. Increasing evidence has shown that the levels of YBX1 protein were closely associated with multidrug resistance, relapse, metastasis and poor prognosis in cancers. However, its role in nasopharyngeal carcinoma (NPC) metastasis remains unknown. In our study, we discovered that the expression of YBX1 was increased in nasopharyngeal carcinoma tissues. YBX1 protein levels positively correlated with T stage and metastasis of NPC patients. Moreover, expression of YBX1 was negatively correlated with membrane E-cadherin levels and positively correlated with Vimentin expression. In vitro, the expression of YBX1 was closely related to the invasive and migratory ability of nasopharyngeal carcinoma cells. Knockdown of YBX1 inhibited migration and invasion in 5-8F cells, and over-expression of YBX1 promoted CNE1 cells migration and invasion. Transforming growth factor-ß1 (TGF-ß1) treatment led to epithelial-to-mesenchymal transition (EMT) in CNE1 cells accompanied by elevated YBX1 expression. On the contrary, knockdown of YBX1 partially inhibited the TGF-ß1-induced CNE1 cell migration, together with changes of EMT-associated markers. Our study revealed that TGF-ß1/YBX1 signaling might be one of novel mechanisms mediating EMT in NPC, providing a new target for the treatment of nasopharyngeal carcinoma.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma/patologia , Movimento Celular , Neoplasias Nasofaríngeas/patologia , Proteína 1 de Ligação a Y-Box/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Carcinoma/metabolismo , Proliferação de Células , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/metabolismo , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Células Tumorais Cultivadas
16.
J Trace Elem Med Biol ; 29: 136-44, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25081494

RESUMO

The hypoglycemic activity of chromium methionine (CrMet) in alloxan-induced diabetic (AID) mice was investigated and compared with those of chromium trichloride hexahydrate (CrCl3·6H2O) and chromium nicotinate (CrNic) through a 15-day feeding experiment. The acute oral toxicity of CrMet was also investigated in ICR (Institute for Cancer Research) mice by a single oral gavage. The anti-diabetic activity of CrMet was explored in detail from the aspects of body weight (BW), blood glucose, triglyceride, total cholesterol, liver glycogen levels, aspartate transaminase (AST) and alanine transaminase (ALT) levels. The obtained results showed that CrMet had beneficial effects on glucose and lipid metabolism, and might possess hepatoprotective efficacy for diabetes. Daily treatment with 500 and 1000µg Cr/kg BW of CrMet in AID mice for 15 days indicated that this low-molecular-weight organic chromium complex had better bioavailability and more beneficial effects on diabetics than CrCl3·6H2O. CrMet also had advantage over CrNic in the control of AST and ALT activities. Acute toxicity studies revealed that CrMet had low toxicity potential and relatively high safety margins in mice with the LD50 value higher than 10.0g/kg BW. These findings suggest that CrMet might be of potential value in the therapy and protection of diabetes.


Assuntos
Cromo/administração & dosagem , Cromo/toxicidade , Hipoglicemiantes/farmacologia , Metionina/administração & dosagem , Metionina/toxicidade , Testes de Toxicidade Aguda , Administração Oral , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/patologia , Glicogênio/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos ICR , Tamanho do Órgão/efeitos dos fármacos , Triglicerídeos/sangue
17.
Artigo em Inglês | MEDLINE | ID: mdl-23871975

RESUMO

The ground state absorption spectra of [NiF6](4-) clusters with orthorhombic symmetry (Ni(2+) in NiF2 crystal and Ni(2+)-doped ZnF2 crystal, D2h point group) are theoretically calculated and assigned by diagonalization of 45×45 complete energy matrix for 3d(8) configuration and the spin-Hamiltonian (SH) parameters (zero-field splitting D and E, and g factors gx, gy, gz) are studied by use of high-order perturbation method, in the frame of semi-empirical molecular orbital (MO) scheme based on strong crystal field framework. In those energy matrix, all the configuration interactions though the cubic crystal field (CF), the orthorhombic crystal field, the Coulomb interaction are taken into account. The calculated results are in good agreement with the experimental data. The local structure (bond length and bond angle) of [NiF6](4-) clusters are determined, and the results shows that the structure data given by Stout are more plausible than those given by Baur.


Assuntos
Ferro/química , Modelos Moleculares , Níquel/química , Fenômenos Ópticos , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica , Termodinâmica
18.
Zhonghua Wei Chang Wai Ke Za Zhi ; 15(12): 1252-5, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23268271

RESUMO

OBJECTIVE: To investigate the perioperative and postoperative long-term complications of procedure for prolapse and hemorrhoids(PPH) for the treatment of circular internal hemorrhoids and circular mixed hemorrhoids. METHODS: A retrospective study was performed in 2152 patients with circular internal hemorrhoids and circular mixed hemorrhoids eligible for PPH from January 2002 to December 2011. The perioperative and postoperative long-term complications were recorded and assessed. RESULTS: The median length of follow-up was 73 months. Perioperative complications and adverse events were reported including acute urinary retention(n=360, 16.7%) which was managed by temporary cathether indwelling, anastomotic bleeding(n=45, 2.1%) managed by surgical or endoscopic procedures, chronic anoperineal sustained pain(n=30, 1.4%) managed by local treatment or stapler removal, and thrombosed external hemorrhoid(n=28, 1.2%) managed by conservative treatment or resection. Long-term postoperative complications were reported including mild fecal incontinence(n=112, 6.3%), postoperative recurrence(n=82, 4.6%), anal distention and defecatory urgency(n=50, 2.8%), anastomotic stenosis(n=4, 0.2%). Postoperative recurrence developed in 82 patients(4.6%), 28 of whom were managed by repeat PPH and 54 by conservative treatment. CONCLUSION: PPH appears to be a safe technique for patients with circular internal hemorrhoids and circular mixed hemorrhoids.


Assuntos
Hemorroidas/diagnóstico , Complicações Pós-Operatórias , Procedimentos Cirúrgicos do Sistema Digestório , Hemorroidas/cirurgia , Humanos , Período Pós-Operatório , Prolapso , Recidiva , Estudos Retrospectivos , Trombose
19.
Artigo em Inglês | MEDLINE | ID: mdl-23022614

RESUMO

The complete energy matrices (45 × 45) including low symmetry ligand field (C(4v)) and Coulomb interactions for 3d(8) ions have been constructed, and the high-order perturbation formulas of spin-Hamiltonian (SH) parameters g factors g(//), g(⊥) and zero-field splitting (ZFS) parameter D for ground state (3)A(2g) of the 3d(8) ions in the tetragonal symmetry environment have been derived. In those formulas both the crystal field (CF) mechanism and the charge transfer (CT) mechanism are taken into account. The complete energy matrices and the high-order perturbation formulas are applied to calculate the energy levels and SH parameters of the Ni(2+) ion in LiCl crystal respectively. The results are in reasonable agreement with the experimental data and indicate that CT mechanism plays important role in the understanding of SH parameters, especially the g factors. All the multiplet energy are assigned theoretically and the local structures of LiCl:Ni(2+) are established.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica , Cloreto de Lítio/química , Níquel/química , Cátions Bivalentes/química , Cristalização
20.
Chin Med J (Engl) ; 125(11): 1975-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22884064

RESUMO

BACKGROUND: Curcumin, an active ingredient of turmeric with antioxidant and anti-inflammatory properties has recently been reported to have anticonvulsant effects in several animal models of epilepsy. This study aimed to investigate the effects of curcumin on the pilocarpine rat model of status epilepticus. METHODS: The effect of intraperitoneal administration of curcumin (30, 100, and 300 mg/kg) on pilocarpine-induced seizures in rats was tested. The correlation between seizure activity and hippocampal levels of nitric oxide synthase and free radicals was quantified. Whether curcumin treatment modulated these parameters was also investigated. RESULTS: Curcumin significantly increased seizure threshold at doses of 100 and 300 mg/kg. Rats with pilocarpine- induced seizures showed significantly elevated levels of malonaldehyde, nitric oxide synthase, and lactate dehydrogenase, but decreased levels of superoxide dismutase and glutathione compared with normal control rats. At doses of 100 and 300 mg/kg, curcumin reversed the effects of pilocarpine-induced seizures on nitric oxide synthase, lactate dehydrogenase, glutathione, and superoxide dismutase. However, curcumin did not restore the elevated malonaldehyde levels. CONCLUSION: Curcumin has anticonvulsant activity in the pilocarpine rat model of seizures, and that modulation of free radicals and nitric oxide synthase may be involved in this effect.


Assuntos
Anticonvulsivantes/uso terapêutico , Antioxidantes/uso terapêutico , Curcumina/uso terapêutico , Pilocarpina/toxicidade , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Animais , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Convulsões/metabolismo , Superóxido Dismutase/metabolismo
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