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1.
Cell Commun Signal ; 22(1): 69, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273292

RESUMO

Tumors of the digestive system pose a significant threat to human health and longevity. These tumors are associated with high morbidity and mortality rates, leading to a heavy economic burden on healthcare systems. Several intratumoral microorganisms are present in digestive system tumors, and their sources and abundance display significant heterogeneity depending on the specific tumor subtype. These microbes have a complex and precise function in the neoplasm. They can facilitate tumor growth through various mechanisms, such as inducing DNA damage, influencing the antitumor immune response, and promoting the degradation of chemotherapy drugs. Therefore, these microorganisms can be targeted to inhibit tumor progression for improving overall patient prognosis. This review focuses on the current research progress on microorganisms present in the digestive system tumors and how they influence the initiation, progression, and prognosis of tumors. Furthermore, the primary sources and constituents of tumor microbiome are delineated. Finally, we summarize the application potential of intratumoral microbes in the diagnosis, treatment, and prognosis prediction of digestive system tumors. Video Abstract.


Assuntos
Neoplasias do Sistema Digestório , Humanos , Neoplasias do Sistema Digestório/diagnóstico , Neoplasias do Sistema Digestório/genética , Neoplasias do Sistema Digestório/patologia , Dano ao DNA
2.
J Exp Bot ; 74(15): 4503-4519, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37170764

RESUMO

The lengths of the basal internodes is an important factor for lodging resistance of maize (Zea mays). In this study, foliar application of coronatine (COR) to 10 cultivars at the V8 growth stage had different suppression effects on the length of the eighth internode, with three being categorized as strong-inhibition cultivars (SC), five as moderate (MC), and two as weak (WC). RNA-sequencing of the eighth internode of the cultivars revealed a total of 7895 internode elongation-regulating genes, including 777 transcription factors (TFs). Genes related to the hormones cytokinin, gibberellin, auxin, and ethylene in the SC group were significantly down-regulated compared to WC, and more cell-cycle regulatory factors and cell wall-related genes showed significant changes, which severely inhibited internode elongation. In addition, we used EMSAs to explore the direct regulatory relationship between two important TFs, ZmABI7 and ZmMYB117, which regulate the cell cycle and cell wall modification by directly binding to the promoters of their target genes ZmCYC1, ZmCYC3, ZmCYC7, and ZmCPP1. The transcriptome reported in this study will provide a useful resource for studying maize internode development, with potential use for targeted genetic control of internode length to improve the lodging resistance of maize.


Assuntos
Ácidos Indolacéticos , Zea mays , Zea mays/metabolismo , Ácidos Indolacéticos/metabolismo , Giberelinas/metabolismo , Transcriptoma , Análise de Sequência de RNA , Regulação da Expressão Gênica de Plantas
3.
J Ophthalmol ; 2023: 9981060, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36994448

RESUMO

Purpose: To evaluate the association between visual-related quality of life (VRQoL) and visual field (VF) loss in patients with primary angle-closure glaucoma (PACG). Methods: In this case-control study, a total of 79 patients with PACG (with or without VF detects) and 35 healthy controls were included. The patients underwent the 25-item National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25), clinical examination, and VF testing. VF defects were identified by simplified Hodapp's classification. NEI VFQ-25 scores were compared between the three groups. Results: No significant differences were found in gender, VFQ rating for "composite score" and "color vision" between the three groups. PACG patients with VF loss were most likely to be older and had lower best corrected visual acuity (BCVA), spherical equivalent (SE), mean deviation (MD), and visual field index (VFI), but higher pattern standard deviation (PSD) (all P < 0.05). Furthermore, patients with VF loss had significantly lower NVE-VFQ-25 subscale scores for general health, general vision, ocular pain, near activities, distance activities, social functioning, mental health, role difficulties, dependency, driving, and peripheral vision than PACG patients without VF loss and healthy controls (all P < 0.05). VFI (ß = 1.498, P=0.003) and MD (ß = -3.891, P=0.016) were significantly correlated with Role Difficulties scores. Additionally, PSD was significantly correlated with Peripheral Vision scores (ß = -1.346, P=0.003). Conclusions: PACG patients with VF loss reported lower NEI VFQ-25 composite and subscale scores. VF indices including VFI, MD, and PSD were strongly correlated with VRQoL as assessed by NEI VFQ-25; thus, VRQoL may be significantly impacted by glaucomatous VF defects.

4.
mSphere ; 8(1): e0038822, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36537786

RESUMO

An experimental gonococcal vaccine consisting of outer membrane vesicles (OMVs) and microsphere (ms)-encapsulated interleukin-12 (IL-12 ms) induces Th1-driven immunity, with circulating and genital antibodies to Neisseria gonorrhoeae, after intravaginal (i.vag.) administration in female mice, and generates resistance to vaginal challenge infection. Because i.vag. administration is inapplicable to males and may not be acceptable to women, we determined whether intranasal (i.n.) administration would generate protective immunity against N. gonorrhoeae. Female and male mice were immunized i.n. with gonococcal OMVs plus IL-12 ms or blank microspheres (blank ms). Responses to i.n. immunization were similar to those with i.vag. immunization, with serum IgG, salivary IgA, and vaginal IgG and IgA antigonococcal antibodies induced when OMVs were administered with IL-12 ms. Male mice responded with serum IgG and salivary IgA antibodies similarly to female mice. Gamma interferon (IFN-γ) production by CD4+ T cells from iliac lymph nodes was elevated after i.n. or i.vag. immunization with OMVs plus IL-12 ms. Female mice immunized with OMVs plus IL-12 ms by either route resisted challenge with N. gonorrhoeae to an equal extent, and resistance generated by i.n. immunization extended to heterologous strains of N. gonorrhoeae. Detergent-extracted OMVs, which have diminished lipooligosaccharide, generated protective immunity to challenge similar to native OMVs. OMVs from mutant N. gonorrhoeae, in which genes for Rmp and LpxL1 were deleted to eliminate the induction of blocking antibodies against Rmp and diminish lipooligosaccharide endotoxicity, also generated resistance to challenge infection similar to wild-type OMVs when administered i.n. with IL-12 ms. IMPORTANCE We previously demonstrated that female mice can be immunized intravaginally with gonococcal outer membrane vesicles (OMVs) plus microsphere (ms)-encapsulated interleukin-12 (IL-12 ms) to induce antigonococcal antibodies and resistance to genital tract challenge with live Neisseria gonorrhoeae. However, this route of vaccination may be impractical for human vaccine development and is inapplicable to males. Because intranasal immunization has previously been shown to induce antibody responses in both male and female genital tracts, we have evaluated this route of immunization with gonococcal OMVs plus IL-12 ms. In addition, we have refined the composition of gonococcal OMVs to reduce the endotoxicity of lipooligosaccharide and to eliminate the membrane protein Rmp, which induces countereffective blocking antibodies. The resulting vaccine may be more suitable for ultimate translation to human application against the sexually transmitted infection gonorrhea, which is becoming increasingly resistant to treatment with antibiotics.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Feminino , Masculino , Humanos , Camundongos , Animais , Anticorpos Bloqueadores , Anticorpos Antibacterianos , Gonorreia/prevenção & controle , Interleucina-12 , Vacinas Bacterianas , Interferon gama , Imunoglobulina G , Imunoglobulina A , Imunidade
5.
Front Microbiol ; 13: 953552, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958128

RESUMO

Knowledge of the spatial-temporal variations of soil organic carbon (SOC) quantity and quality and its microbial regulation mechanisms is essential for long-term SOC sequestration in agroecosystems; nevertheless, this information is lacking in the process of walnut plantations. Here, we used the modified Walkley-Black method, phospholipid fatty acid analysis, and micro-plate enzyme technique to analyze the evolution of SOC stocks and quality/lability as well as microbial communities and enzyme activities at different soil depths in walnut plantations with a chronosequence of 0-, 7-, 14-, and 21-years in the Eastern Taihang Mountains, China. The results indicated that long-term walnut plantations (14-and 21-years) enhanced SOC stocks, improved SOC quality/lability (as indicated by the lability index), and promoted microbial growth and activities (i.e., hydrolase and oxidase activities) in the 0-40 cm soil layers. Besides, these above-mentioned SOC-and microbial-related indices (except for oxidase activities) decreased with increasing soil depths, while oxidase activities were higher in deeper soils (40-60 cm) than in other soils (0-40 cm). The partial least squares path model also revealed that walnut plantation ages and soil depths had positive and negative effects on microbial attributes (e.g., enzyme activities, fungal and bacterial communities), respectively. Meanwhile, the SOC stocks were closely related to the fungal community; meanwhile, the bacterial community affected SOC quality/liability by regulating enzyme activities. Comprehensively, long-term walnut plantations were conducive to increasing SOC stocks and quality through altering microbial communities and activities in the East Taihang Mountains in Hebei, China.

6.
Int J Gen Med ; 15: 5173-5179, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35637700

RESUMO

Purpose: To evaluate visual-related quality of life (VR-QoL) and its association with optic nerve head microvasculature in individuals with nonarteritic anterior ischemic optic neuropathy (NAION) evaluated at the acute stage. Methods: In this retrospective case-control study, 23 NAION eyes at the acute stage and 25 age and gender matched healthy eyes were included, respectively. All included eyes underwent a complete ophthalmic examination including optical coherence tomography (OCT) and OCT angiography (OCTA). The Chinese version of the National Eye Institute Visual Function Questionnaire-25 (CHI-NEI-VFQ-25) was applied to assess VR-QoL in individuals consecutively visited at an ophthalmic center. Descriptive and analytic statistics were employed. Results: There were no significant differences on age, gender, socioeconomic and education level (P > 0.05), but best-corrected visual acuity (BCVA) differences were reported between cases and controls (P < 0.05). Each peripapillary retinal nerve fiber layer (RNFL) thickness was higher but peripapillary vessel density (VD) and VR-QoL scores for all subscales were significantly lower in cases when compared with controls, respectively (P < 0.05). Particularly, pearson's partial correlation analysis restricted to eyes with NAION revealed stronger correlations between peripapillary RNFL measurements, VD and VR-QoL. Conclusion: NAION at the acute stage affects VR-QoL in Chinese individuals. Some peripapillary RNFL measurements and VD correlated with VR-QoL. Retinal anatomic and blood flow examinations and inventions in patients with NAION are necessary to facilitate VR-QoL and disease control.

7.
Quant Imaging Med Surg ; 12(2): 1549-1557, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35111647

RESUMO

BACKGROUND: Quantitative assessments based on optical coherence tomographic angiography (OCTA) may have potential promising value in the early detection of non-arteritic anterior ischemic optic neuropathy (NA-AION), but there is limited information on the ability of OCTA to distinguish eyes with NA-AION. This study was conducted to evaluate the ability of measurements of peripapillary perfusion using OCTA to distinguish healthy eyes from eyes with NA-AION. METHODS: In this retrospective case-control study, newly diagnosed NA-AION patients and healthy controls matched at a ratio of 1:3 by gender and age (±5 years) were enrolled from 1 September 2020 to 30 June 2021. Peripapillary vessel density (pVD) was examined based on the area of vessels by means of a 4.5 mm OCTA scan. In addition, peripapillary retinal nerve fiber layer (pRNFL) thickness was obtained from structural optical coherence tomography (OCT), as was the area under the receiver operating characteristic (ROC) curve (AUC). RESULTS: A total of 29 eyes from 28 cases with NA-AION and 99 healthy eyes from 68 participants were imaged. All participants were Chinese. The NA-AION group showed a significant reduction of the pVD (P<0.001), while all subregions of pRNFL thickness were prominent in all 8 quadrants (P>0.05). The pVD of the optic disc in the superior temporal (ST) region showed better diagnostic accuracy (AUC =0.86) in discriminating the NA-AION group from healthy controls. After adjusting for confounders, ST was independently associated with the presence of NA-AION [odds ratio (OR) =0.971, 95% confidence interval (CI): 0.943-0.990, P=0.048]. CONCLUSIONS: Decreased pVD was detected by non-invasive measurements of OCTA in the eyes of NA-AION patients. This finding may reveal an association between the ST region and the presence of NA-AION. The pVD may have potential diagnostic ability and may serve as an additional biomarker in the management of the disease.

8.
Front Genet ; 12: 672884, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995498

RESUMO

Drought is one of the major abiotic stress factors limiting peanut production. It causes the loss of pod yield during the pod formation stage. Here, one previously identified drought-tolerant cultivar, "L422" of peanut, was stressed by drought (35 ± 5%) at pod formation stage for 5, 7, and 9 days. To analyze the drought effects on peanut, we conducted physiological and transcriptome analysis in leaves under well-watered (CK1, CK2, and CK3) and drought-stress conditions (T1, T2, and T3). By transcriptome analysis, 3,586, 6,730, and 8,054 differentially expressed genes (DEGs) were identified in "L422" at 5 days (CK1 vs T1), 7 days (CK2 vs T2), and 9 days (CK3 vs T3) of drought stress, respectively, and 2,846 genes were common DEGs among the three-time points. Furthermore, the result of weighted gene co-expression network analysis (WGCNA) revealed one significant module that was closely correlated between drought stress and physiological data. A total of 1,313 significantly up-/down-regulated genes, including 61 transcription factors, were identified in the module at three-time points throughout the drought stress stage. Additionally, six vital metabolic pathways, namely, "MAPK signaling pathway-plant," "flavonoid biosynthesis," "starch and sucrose metabolism," "phenylpropanoid biosynthesis," "glutathione metabolism," and "plant hormone signal transduction" were enriched in "L422" under severe drought stress. Nine genes responding to drought tolerance were selected for quantitative real-time PCR (qRT-PCR) verification and the results agreed with transcriptional profile data, which reveals the reliability and accuracy of transcriptome data. Taken together, these findings could lead to a better understanding of drought tolerance and facilitate the breeding of drought-resistant peanut cultivars.

9.
Exp Ther Med ; 17(3): 2373-2380, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30783489

RESUMO

Podocytes are a major component of the glomerular filtration membrane, and their apoptosis is involved in a variety of nephrotic syndromes. In the current study, the effects and molecular mechanisms of oestrogen on the proliferation and apoptosis of podocytes were investigated to elucidate the role of oestrogen in the pathogenesis of childhood nephrotic syndrome. The cell proliferation of mouse renal podocytes (MPC-5) and human primary renal podocytes was promoted by 17ß-oestradiol (E2) in what appear to be a time-dependent manner. Apoptosis was inhibited by E2 and promoted by the E2 antagonist, tamoxifen. The expression of protein tyrosine phosphatase receptor type O (PTPRO) decreased with the increasing dosage of E2, but increased with the increasing dosage tamoxifen in MPC-5 and human podocytes. The protein, oestrogen receptor (ER)α, was not expressed in MPC-5 and human podocytes. E2 binding to ERß completely eliminated PTPRO expression in MPC-5. In podocytes, PTPRO was phosphorylated by E2 at the Y1007 and associated with tyrosine-protein kinase JAK2 (JAK2) activation, rather than JAK1 activation. PTPRO was involved in the binding of E2 to signal transducer and activator of transcription (STAT)3 at the Y705 and S727 sites, resulting in the phosphorylation of STAT3 in podocytes. Through PTPRO, E2 also regulated the proliferation and apoptosis of podocytes. In conclusion, oestrogen binding to ERß, rather than ERα, promoted the proliferation of podocytes and inhibited the apoptosis of podocytes by inhibiting the expression of PTPRO. The mechanism may be associated with the activation of the JAK2/STAT3 signalling pathway. The current study may provide a novel direction for the treatment of childhood nephrotic syndrome.

10.
J Plant Physiol ; 228: 59-65, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29870879

RESUMO

Coronatine (COR) is a phytotoxin produced by Pseudomonas syringae. Its structure is similar to those of jasmonates (JAs), which play diverse roles in multiple plant biotic and abiotic defenses. However, the biological activity of COR is 1000 times greater than the activity of JA. In addition to being involved in the JA pathway, COR affects plant photosynthetic efficiency. In this study, we examined wheat blade pretreatment with COR. Blades treated with COR remained green longer than those of control plants under drought stress conditions, resulting in less yield loss with COR treatment. To investigate the mechanism of COR in drought resistance further, we employed two-dimensional gel electrophoresis technology and matrix-assisted laser desorption/ionization mass spectrometry to sequester and identify key proteins. Six COR-inducible proteins that are located in the chloroplast and involved directly in photosynthesis were found. The wheat homologue of protein gi|326509937 is degradation of periplasmic proteins 1 (DEGP1) in Arabidopsis, which is a response to photosystem II reparation, and was maintained at a low level with COR treatment. Finally, we measured levels of chlorophyll and photosynthetic performance to reveal the phenotypic effect of COR. Taken together, the results demonstrate that COR enhances drought tolerance by maintaining high photosynthetic performance.


Assuntos
Aminoácidos/farmacologia , Secas , Indenos/farmacologia , Triticum/metabolismo , Triticum/fisiologia , Clorofila/metabolismo , Cloroplastos/efeitos dos fármacos , Cloroplastos/metabolismo , Eletroforese em Gel Bidimensional , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Fotossíntese/fisiologia , Proteínas de Plantas/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
mSphere ; 3(1)2018.
Artigo em Inglês | MEDLINE | ID: mdl-29404418

RESUMO

It has previously been shown that genital tract infection with Neisseria gonorrhoeae in mice does not induce a state of protective immunity against reinfection but instead suppresses the development of adaptive immune responses against N. gonorrhoeae dependent on transforming growth factor beta (TGF-ß) and interleukin 10 (IL-10). Intravaginal administration during gonococcal infection of IL-12 encapsulated in biodegradable microspheres (IL-12/ms) reverses the immunosuppression and promotes the production of gamma interferon (IFN-γ) and of specific antibodies in serum and genital secretions and accelerates clearance of the infection. In this study, microspheres were shown to remain largely within the genital tract lumen and to release IL-12 over the course of 4 days. Antigonococcal IgA and IgG antibodies induced by IL-12/ms treatment reacted with antigenically different strains of N. gonorrhoeae and led to resistance to reinfection with heterologous and homologous strains. Immune resistance to reinfection persisted for at least 6 months after clearance of the primary infection. Experiments performed with immunodeficient strains of mice lacking either IFN-γ or B cells demonstrated that both IFN-γ and B cells were necessary for the IL-12-induced generation of immune responses to N. gonorrhoeae and the resulting accelerated clearance of the infection. It is therefore concluded that intravaginally administered IL-12/ms achieves its effect by the sustained release of IL-12 that promotes Th1-driven adaptive immune responses, including the production of specific antigonococcal antibodies that cross-react with multiple strains of N. gonorrhoeae. IL-12-enhanced immunity to N. gonorrhoeae can be recalled against reinfection after prolonged intervals and is dependent upon both IFN-γ and antibody production by B cells. IMPORTANCE Genital infection with Neisseria gonorrhoeae (gonorrhea) is a significant cause of reproductive tract morbidity in women, leading to pelvic inflammatory disease, tubal factor infertility, and increased risk for ectopic pregnancy. WHO estimates that 78 million new infections occur annually worldwide. In the United States, >350,000 cases are reported annually, but the true incidence is probably >800,000 cases/year. Increasing resistance to currently available antibiotics raises concern that gonorrhea might become untreatable. Infection does not induce a state of immune protection against reinfection. Previous studies have shown that N. gonorrhoeae suppresses the development of adaptive immune responses by mechanisms dependent on the regulatory cytokines TGF-ß and IL-10. This study shows that intravaginal treatment of gonococcal infection in female mice with microencapsulated IL-12 induces persisting anamnestic immunity against reinfection with N. gonorrhoeae, even of antigenically diverse strains, dependent on T-cell production of IFN-γ and B-cell production of antibodies.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2329-32, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26672319

RESUMO

Synchrotron radiation X-ray absorption near edge structure was employed to study the arsenic (As) speciation in 13 Pteris vittata L. populations collected from 7 provinces, cities, and autonomous regions in China. As in roots of P. vittata was mainly combined with oxygen (O), with a small amount of As combined with glutathione (GSH). Populations from Hunan and Guangxi provinces showed higher percentages of As-GSH in soots. As in roots of P. vittata was predominated with As(V), with the percentage of As(V) to the total As being 59.6±0.6%~83.8±3.8%. The As(V) percentage was in the order of HN5HN3>HN1>TW>CQ>AH>FJ>HN5>HN2>GX2>GX3>HN4>GX1, within the range of 2.4%~12.9%. Different from that in roots, As in shoots was predominated with As(III), with no As(V) detected. The disclosure of As speciation in the roots and shoots of P. vittata contributes to the future research on As accumulation mechanism.


Assuntos
Arsênio/química , Pteris/química , Poluentes do Solo/análise , China , Raízes de Plantas/química , Síncrotrons
13.
J Infect Dis ; 208(11): 1821-9, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24048962

RESUMO

Gonorrhea remains one of the most frequent infectious diseases, and Neisseria gonorrhoeae is emerging as resistant to most available antibiotics, yet it does not induce a state of specific protective immunity against reinfection. Our recent studies have demonstrated that N. gonorrhoeae proactively suppresses host T-helper (Th) 1/Th2-mediated adaptive immune responses, which can be manipulated to generate protective immunity. Here we show that intravaginally administered interleukin 12 (IL-12) encapsulated in sustained-release polymer microspheres significantly enhanced both Th1 and humoral immune responses in a mouse model of genital gonococcal infection. Treatment of mice with IL-12 microspheres during gonococcal challenge led to faster clearance of infection and induced resistance to reinfection, with the generation of gonococcus-specific circulating immunoglobulin G and vaginal immunoglobulin A and G antibodies. These results suggest that local administration of microencapsulated IL-12 can serve as a novel therapeutic and prophylactic strategy against gonorrhea, with implications for the development of an effective vaccine.


Assuntos
Imunidade Adaptativa , Anticorpos Antibacterianos/biossíntese , Gonorreia/imunologia , Interleucina-12/administração & dosagem , Neisseria gonorrhoeae/imunologia , Administração Intravaginal , Animais , Anticorpos Antibacterianos/análise , Modelos Animais de Doenças , Composição de Medicamentos , Ensaio de Imunoadsorção Enzimática , Feminino , Gonorreia/tratamento farmacológico , Gonorreia/prevenção & controle , Humanos , Interleucina-10/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Microesferas , Fator de Crescimento Transformador beta/imunologia
14.
Lab Chip ; 13(7): 1316-24, 2013 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-23370691

RESUMO

DNA fluorescence in situ hybridization (FISH) is a powerful cytogenetic assay, but conventional sample-preparation methods for FISH do not support large-scale high-throughput data acquisition and analysis, which are potentially useful for several biomedical applications. To address this limitation, we have developed a novel FISH sample-preparation method based on generating a centimetre-sized cell array, in which all cells are precisely positioned and separated from their neighbours. This method is simple and capable of patterning nonadherent human cells. We have successfully performed DNA FISH on the single-cell arrays, which facilitates analysis of the FISH results with the FISH-FINDER computer program.


Assuntos
DNA/genética , Hibridização in Situ Fluorescente/métodos , Análise de Célula Única/métodos , Análise Serial de Tecidos/métodos , Humanos , Células K562 , Propriedades de Superfície
16.
Sci Total Environ ; 442: 143-51, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23178774

RESUMO

Arsenic (As) contamination poses a high risk to human health. Phytoremediation based on As hyperaccumulator Pteris vittata has been utilized on large areas of contaminated farmland in southern China. However, the reason for the observed differences in As removal among P. vittata populations remains unclear. In this study, spores of four P. vittata populations were collected from four neighboring sites with varying soil As concentration (from 108 mg·kg(-1) to 7527 mg·kg(-1)) and then cultured in a controlled environment to analyze their differing abilities in terms of As accumulation and tolerance. The results indicate that populations from low-As habitats exhibited 80% greater shoot As concentrations compared with those from high-As habitats. On the other hand, populations from high-As habitats exhibited approximately five times greater biomass compared with those from low-As habitats when exposed to the same As stress. Thus, the As accumulation and tolerance of P. vittata were suggested to be two independent processes. Further investigations reveal that the As absorption and As species conversion occurring in roots are two essential activities that bridge the soil As concentration and the responses of P. vittata to As. Depending on the As concentration of the target soil, the selection of different P. vittata populations can result in approximately an eight-fold difference in terms of remediation efficiency.


Assuntos
Arsênio/análise , Monitoramento Ambiental/métodos , Pteris/crescimento & desenvolvimento , Poluentes do Solo/análise , Biodegradação Ambiental , Biomassa , China , Mineração , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Pteris/química , Plântula/química , Plântula/crescimento & desenvolvimento , Esporos/crescimento & desenvolvimento
17.
Environ Pollut ; 161: 1-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22230060

RESUMO

Arsenic (As) reduction and translocation are key processes for As hyperaccumulation by the hyperaccumulator Pteris vittata L. Micro-X-ray adsorption spectroscopy of P. vittata's rhizoid tissues revealed that As reduction mainly occurred in endodermis during translocation from epidermis to vascular bundle. Prior to reduction, arsenate (As (V)) translocation was an active process requiring energy and employing a phosphate (P) transporter. Use of a synchrotron X-ray microprobe showed that As (V) and P were cotransported and that this process could be enhanced by As (V) exposure or P deficiency but restrained by energy release inhibition caused by 2,4-dinitrophenol or sodium orthovanadate. In contrast, after As reduction, As(III) translocation differed from P translocation and was more efficient, appearing free from the apparent endodermal blockage. The results here revealed the role of the P transporter on As translocation as well as the key role of As reduction in As hyperaccumulation by P. vittata.


Assuntos
Arsênio/metabolismo , Fósforo/metabolismo , Pteris/metabolismo , Poluentes do Solo/metabolismo , Arsênio/análise , Biodegradação Ambiental , Modelos Químicos , Fósforo/análise , Pteris/química , Poluentes do Solo/análise , Espectroscopia por Absorção de Raios X
18.
Front Microbiol ; 2: 52, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21833308

RESUMO

It is well-known that gonorrhea can be acquired repeatedly with no apparent development of protective immunity arising from previous episodes of infection. Symptomatic infection is characterized by a purulent exudate, but the host response mechanisms are poorly understood. While the remarkable antigenic variability displayed by Neisseria gonorrhoeae and its capacity to inhibit complement activation allow it to evade destruction by the host's immune defenses, we propose that it also has the capacity to avoid inducing specific immune responses. In a mouse model of vaginal gonococcal infection, N. gonorrhoeae elicits Th17-driven inflammatory-immune responses, which recruit innate defense mechanisms including an influx of neutrophils. Concomitantly, N. gonorrhoeae suppresses Th1- and Th2-dependent adaptive immunity, including specific antibody responses, through a mechanism involving TGF-ß and regulatory T cells. Blockade of TGF-ß alleviates the suppression of specific anti-gonococcal responses and allows Th1 and Th2 responses to emerge with the generation of immune memory and protective immunity. Genital tract tissues are naturally rich in TGF-ß, which fosters an immunosuppressive environment that is important in reproduction. In exploiting this niche, N. gonorrhoeae exemplifies a well-adapted pathogen that proactively elicits from its host innate responses that it can survive and concomitantly suppresses adaptive immunity. Comprehension of these mechanisms of gonococcal pathogenesis should allow the development of novel approaches to therapy and facilitate the development of an effective vaccine.

19.
mBio ; 2(3): e00095-11, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21610119

RESUMO

UNLABELLED: The immune response to Neisseria gonorrhoeae is poorly understood, but its extensive antigenic variability and resistance to complement are thought to allow it to evade destruction by the host's immune defenses. We propose that N. gonorrhoeae also avoids inducing protective immune responses in the first place. We previously found that N. gonorrhoeae induces interleukin-17 (IL-17)-dependent innate responses in mice and suppresses Th1/Th2-dependent adaptive responses in murine cells in vitro through the induction of transforming growth factor ß (TGF-ß). In this study using a murine model of vaginal gonococcal infection, mice treated with anti-TGF-ß antibody during primary infection showed accelerated clearance of N. gonorrhoeae, with incipient development of Th1 and Th2 responses and diminished Th17 responses in genital tract tissue. Upon secondary reinfection, mice that had been treated with anti-TGF-ß during primary infection showed anamnestic recall of both Th1 and Th2 responses, with the development of antigonococcal antibodies in sera and secretions, and enhanced resistance to reinfection. In mouse knockout strains defective in Th1 or Th2 responses, accelerated clearance of primary infection due to anti-TGF-ß treatment was dependent on Th1 activity but not Th2 activity, whereas resistance to secondary infection resulting from anti-TGF-ß treatment during primary infection was due to both Th1- and Th2-dependent memory responses. We propose that N. gonorrhoeae proactively elicits Th17-driven innate responses that it can resist and concomitantly suppresses Th1/Th2-driven specific adaptive immunity that would protect the host. Blockade of TGF-ß reverses this pattern of host immune responsiveness and facilitates the emergence of protective antigonococcal immunity. IMPORTANCE: Pathogen-host interactions during infectious disease are conventionally thought of as two-way reactions, that of the host against the pathogen and vice versa, with the outcome dependent on which one ultimately prevails. We propose that Neisseria gonorrhoeae, a pathogen that has become extremely well adapted to its exclusive human host, proactively directs the manner in which the host responds in ways that are beneficial to its own survival but detrimental to the host. Gonorrhea is a widely prevalent sexually transmitted infection, and naturally occurring gonococcal strains are becoming resistant to most available antibiotics, yet no effective vaccine has been developed. These new insights into the immune response to N. gonorrhoeae should lead to novel therapeutic strategies and facilitate new approaches to vaccine development.


Assuntos
Anticorpos/administração & dosagem , Memória Imunológica , Neisseria gonorrhoeae/imunologia , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Animais , Anticorpos Antibacterianos/análise , Anticorpos Antibacterianos/sangue , Secreções Corporais/imunologia , Modelos Animais de Doenças , Feminino , Gonorreia/imunologia , Gonorreia/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças dos Roedores/imunologia , Doenças dos Roedores/microbiologia , Doenças dos Roedores/prevenção & controle , Fator de Crescimento Transformador beta/imunologia , Vagina/imunologia , Vagina/microbiologia
20.
J Biomed Opt ; 16(2): 021109, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21361672

RESUMO

Myelin loss and axonal degeneration predominate in many neurological disorders; however, methods to visualize them simultaneously in live tissue are unavailable. We describe a new imaging strategy combining video rate reflectance and fluorescence confocal imaging with coherent anti-Stokes Raman scattering (CARS) microscopy tuned to CH(2) vibration of myelin lipids, applied in live tissue of animals with chronic experimental autoimmune encephalomyelitis (EAE). Our method allows monitoring over time of demyelination and neurodegeneration in brain slices with high spatial resolution and signal-to-noise ratio. Local areas of severe loss of lipid signal indicative of demyelination and loss of the reflectance signal from axons were seen in the corpus callosum and spinal cord of EAE animals. Even in myelinated areas of EAE mice, the intensity of myelin lipid signals is significantly reduced. Using heterozygous knock-in mice in which green fluorescent protein replaces the CX(3)CR1 coding sequence that labels central nervous system microglia, we find areas of activated microglia colocalized with areas of altered reflectance and CARS signals reflecting axonal injury and demyelination. Our data demonstrate the use of multimodal CARS microscopy for characterization of demyelinating and neurodegenerative pathology in a mouse model of multiple sclerosis, and further confirm the critical role of microglia in chronic inflammatory neurodegeneration.


Assuntos
Axônios/patologia , Microscopia/métodos , Esclerose Múltipla/patologia , Fibras Nervosas Mielinizadas/patologia , Análise Espectral Raman/métodos , Animais , Camundongos
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