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1.
New Phytol ; 231(6): 2200-2214, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33454966

RESUMO

Golgi is a critical compartment for both the reutilisation of the essential micronutrient manganese (Mn) and its detoxification. However, whether Mn plays a role in the Golgi remains to be demonstrated in plants. We characterised the function of PML3, a member of the Unknown Protein Family UPF0016, in Mn transport and the regulation of plant growth, Golgi glycosylation and cell wall biosynthesis in Arabidopsis. We also investigated the relationship of PML3 with NRAMP2, a trans-Golgi network localised Mn transporter. PML3-GFP is preferentially localised in the cis-Golgi. PML3 can transport Mn to rescue the hypersensitivity of yeast mutant Δpmr1 to excess Mn. Two mutant alleles of PML3 displayed reduced plant growth and impaired seed development under Mn-deficient conditions. The pml3 mutants also showed impaired Golgi glycosylation and cell wall biosynthesis under Mn deficiency. Double mutations of PML3 and NRAMP2 showed improved plant growth compared with that of single mutants under Mn deficiency, implying that PML3 and NRAMP2 play opposite roles in the regulation of Golgi Mn levels. Our results suggest that PML3 mediates Mn uptake into the Golgi compartments, which is required for proper protein glycosylation and cell wall biosynthesis under Mn-deficient conditions.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Transporte de Cátions , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Parede Celular/metabolismo , Glicosilação , Complexo de Golgi/metabolismo , Manganês/metabolismo
2.
J Integr Plant Biol ; 62(3): 314-329, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30791211

RESUMO

Rice is a major source of cadmium (Cd) intake for Asian people. Indica rice usually accumulates more Cd in shoots and grains than Japonica rice. However, underlying genetic bases for differential Cd accumulation between Indica and Japonica rice are still unknown. In this study, we cloned a quantitative trait locus (QTL) grain Cd concentration on chromosome 7 (GCC7) responsible for differential grain Cd accumulation between two rice varieties by performing QTL analysis and map-based cloning. We found that the two GCC7 alleles, GCC7PA64s and GCC793-11 , had different promoter activity of OsHMA3, leading to different OsHMA3 expression and different shoot and grain Cd concentrations. By analyzing the distribution of different haplotypes of GCC7 among diverse rice accessions, we discovered that the high and low Cd accumulation alleles, namely GCC793-11 and GCC7PA64s , were preferentially distributed in Indica and Japonica rice, respectively. We further showed that the GCC7PA64s allele can be used to replace the GCC793-11 allele in the super cultivar 93-11 to reduce grain Cd concentration without adverse effect on agronomic traits. Our results thus reveal that the QTL GCC7 with sequence variation in the OsHMA3 promoter is an important determinant controlling differential grain Cd accumulation between Indica and Japonica rice.


Assuntos
Cádmio/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Alelos , Oryza/genética , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Locos de Características Quantitativas/genética
3.
Mol Autism ; 5: 52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25694804

RESUMO

BACKGROUND: Autism spectrum disorder (ASD) is characterized by persistent deficits in social communication and interaction, and restrictive and repetitive patterns of behavior, interests or activities. This study aimed to analyze trends in ASD diagnosis and intervention in 20 years of data from the Beijing Stars and Rain Education Institute for Autism (SR), the first autism intervention center in mainland China, and from a recent survey of members of the Heart Alliance, an industry association of autism intervention centers in China. METHODS: We analyzed the registration data at the SR from 1993 to 2012 for a total of 2,222 children who had a parent-reported diagnosis of ASD and 612 of 'autistic tendencies'. Most of the children who were the primary focus of our analyses were age six and under. We also analyzed results of a survey we conducted in 2013 of 100 member centers of the Heart Alliance. Generalized Estimating Equations, multiple linear regression and the Mann-Whitney test were used for data analysis. Statistically significant findings are reported here. RESULTS: The number of hospitals where SR children received their diagnosis increased from several in the early 1990s to 276 at present. The proportion of 'autistic tendencies' diagnosis increased 2.04-fold from 1998 to 2012 and was higher for children diagnosed at a younger age. The mean age at first diagnosis of ASD or 'autistic tendencies' decreased by 0.27 years every decade. A higher level of parental education was statistically significantly associated with an earlier diagnosis of the child. The mean parental age at childbirth increased by about 1.48 years per decade, and the mean maternal age was 1.40 and 2.10 years higher than that in the national population censuses of 2000 and 2010, respectively. At the time of the survey 3,957 children with ASD were being trained at the 100 autism intervention centers. Ninety-seven of these centers opened after the year 2000. Economically underdeveloped regions are still underserved. CONCLUSIONS: This study revealed encouraging trends and remaining challenges in ASD diagnosis and intervention among children at the SR over the past 20 years and the 100 autism intervention centers in China at present.

4.
Planta Med ; 76(5): 489-94, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19844861

RESUMO

Rhizomes of the perennial herb Paris polyphylla have been used in traditional Chinese medicine for hundreds of years. Agricultural production of the rhizomes requires 7-10 years, which is too long to meet the demand of the medicinal industry. Therefore, studies on improving the yield of the herb and shortening the culturing period are imperative. The present work aimed to investigate the effect of sodium bisulfite (NaHSO (3)) on rhizome yield and quality, as well as some related metabolic features of P. polyphylla. The rhizome yield was improved by NaHSO (3) treatment in long-term experiments conducted during 2006 and 2007, with 2 mM NaHSO (3) giving the highest yield. HPLC analysis revealed that NaHSO (3) treatment increased the total saponin content (49 %), including three pennogenin glycosides and two diosgenin glycosides. In a short-term experiment, NaHSO (3) treatment resulted in an enhanced net photosynthetic rate (Pn) for about 4 days without significant changes in the chlorophyll or carotenoid content. The total soluble sugars and sucrose contents in the leaves also significantly increased after 2 mM NaHSO (3) treatment, whereas the starch content changed only slightly. The activities of the enzymes involved in ammonium assimilation (glutamine synthetase [GS] and glutamate dehydrogenase [GDH]) were not significantly influenced. In a long-term experiment, chlorophylls and carotenoids were not significantly affected, and neither was the starch content in leaves, but the total soluble sugars and sucrose contents in leaves increased significantly. The NaHSO (3) treatment significantly increased GS and GDH activities. These results indicate that NaHSO (3) treatment improved the rhizome yield in P. polyphylla, not only through enhancement of Pn but also by improving carbohydrate accumulation and ammonium assimilation. The increased saponin content after NaHSO (3) treatment was indicative of high rhizome quality.


Assuntos
Medicamentos de Ervas Chinesas/química , Magnoliopsida/química , Rizoma/química , Sulfitos/química , Agricultura , Química Farmacêutica/métodos , Magnoliopsida/efeitos dos fármacos , Magnoliopsida/crescimento & desenvolvimento , Medicina Tradicional Chinesa , Fotossíntese/efeitos dos fármacos , Rizoma/efeitos dos fármacos , Rizoma/crescimento & desenvolvimento
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 42(8): 565-8, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19115618

RESUMO

OBJECTIVE: To use a mathematical model and computer simulation to study transmission dynamics and control of schistosomiasis in mountainous regions of Sichuan. METHODS: Based on studies of schistosomiasis japonica transmission in 20 villages in mountainous regions of Sichuan, a mathematical model was developed to characterize the impact of local environmental factors on transmission intensity. The model integrated site-specific factors and was calibrated to field epidemiological data from 3 subset villages. The dichotomic method was then used to predict different control measures. RESULTS: The study showed high variations in prevalence of infection and infection intensity across villages, ranging between 3%-73%, 0.1-100 epg (eggs per gram stool), respectively. Important factors including occupation of local residents, exposure to contaminated water, microclimatic characteristics were integrated in the model. The predictions of dichotomic models showed that continuing chemotherapy (coverage between 50%-60%) could reduce infection intensities to 30%-80%, but could not change local transmission potential; therefore, the termination of chemotherapy would be followed by bouncing back of transmission. Sustaining targeted environmental interventions through snail and parasite oval control at certain coverage (30%-50%, respectively) could reduce the transmission to relatively stable levels. The model predictions showed that an integrated control (e.g., including both chemotherapy and environmental interventions) could suppress the transmission to an undetectable level even interruption of transmission between 5-10 years. CONCLUSION: The study demonstrated the feasibility of using a dynamic model, calibrated to local data, to gain insights into complicated processes underlying the transmission and informing site-specific control strategies.


Assuntos
Meio Ambiente , Modelos Teóricos , Esquistossomose Japônica/transmissão , Adolescente , Adulto , Animais , Criança , Pré-Escolar , China , Humanos , Pessoa de Meia-Idade , Schistosoma japonicum , Esquistossomose Japônica/epidemiologia , Esquistossomose Japônica/prevenção & controle , Caramujos/parasitologia
6.
World J Gastroenterol ; 10(2): 306-8, 2004 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-14716846

RESUMO

AIM: To evaluate if HB vaccination can yield a booster effect on the anti-HBs level of those naturally acquired HBV positive markers. METHODS: Sera were collected from 1399 newly enrolled university students aged between 18-20 years at the entrance medical examination in 2001. Forty-four students (28 males and 16 females) with positive serum anti-HBs and anti-HBc markers served as an observation group and another 44 students (24 males and 20 females) without any HBV markers as the control. HB vaccination was given to all the students without positive serum HBsAg according to 0, 1, 6 month regimen and the peripheral venous blood was sampled from those of both observation and control groups for anti-HBs detection one month after the second and third doses. Anti-HBs levels were measured by ELISA. RESULTS: The seroconversion rate of anti-HBs in the control group was 100% after the second dose, but the geometric mean titers (GMTs) were low. The tendency of serum anti-HBs changes after the 3rd dose was completely different between the two groups. Although more than half of those with positive anti-HBs and anti-HBc showed a mild increase of anti-HBs levels after the 2nd boosting dose (mean anti-HBs level was 320:198 mIU), but the increase of serum anti-HBs titer was much smaller than that in the control group. The averages of their initial serum anti-HBs levels and the levels after the 2nd and 3rd doses were 198, 320 and 275 mIU respectively. All the subjects from the control group had an obvious increase in their serum anti-HBs levels which was nearly 4 times the baseline level (302:78 mIU). CONCLUSION: HB vaccination can not enhance anti-HBs levels in those with positive serum anti-HBs and anti-HBc markers.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/imunologia , Hepatite B/prevenção & controle , Adolescente , Adulto , Biomarcadores , Feminino , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/sangue , Humanos , Imunização Secundária , Masculino
7.
World J Gastroenterol ; 9(10): 2353-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14562411

RESUMO

AIM: To determine whether or not a low dose of HB vaccine can be effectively used in the rapid vaccination. METHODS: Rapid vaccination (0, 1, 2 months) with low dose (5 microg) or routine dose (10 microg) HB vaccine was studied in 250 subjects (130 school children and 120 university students). Serum from all the participants was tested for HBsAg, anti-HBs and anti-HBc at 1, 3 and 7 months after the first dose of vaccination and all subjects were serum HBV marks negative before the vaccination. Non-responders to a complete initial vaccination from university students were given an additional vaccination with 10 microg of HB vaccine and their serum anti-HBs was tested again one month later. RESULTS: One month after the third dose of vaccination (third month) sero-conversion rates and geometric mean titer (GMTs) were significantly (P<0.01) higher in the routine dose (resp. 89% and 106.8) than in the low dose group (resp. 72% and 59.5). Sero-conversion rates and GMTs were maintained stable for another 4 months in both groups. After an additional vaccination to non-responders with 10 microg HB vaccine, 17/23 subjects (13/15 from those vaccinated with 5 microg vaccine and 4/8 from those vaccinated with 10 microg vaccine) became anti-HBs positive, yielding similar sero-conversion rates for both dose groups. CONCLUSION: Higher sero-conversion rates and GMTs were reached in those vaccinated with 10 microg HB vaccine than in those vaccinated with 5 microg HB vaccine after a complete vaccination with a 0, 1, 2 month scheme. But the subjects vaccinated with 5 microg vaccine can also reach the similar sero-conversion rate after an additional vaccination.


Assuntos
Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Vacinação em Massa/métodos , Adolescente , Adulto , Criança , Anticorpos Anti-Hepatite B/sangue , Humanos , Fatores de Tempo
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