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1.
Altern Ther Health Med ; 29(6): 350-357, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37347692

RESUMEN

Context: Gonorrhea, a highly communicable, sexually transmitted infection, remains a major public-health concern globally. In recent years, Zhejiang province, an eastern province, has had the highest incidence of gonorrhea in China. Objective: The study intended to identify the geographic distribution patterns and spaciotemporal clustering characteristics of the disease's incidence in Zhejiang between 2016 and 2020, to understand the spatial epidemiology of gonorrhea and to pinpoint the locations with relatively high risks of gonorrhea, the hotspots, which could be the key areas for disease prevention and control. Design: The research team performed a retrospective, spaciotemporal-clustering analysis of data about newly reported gonorrhea cases from January 2016 to December 2020 in Zhejiang province, using the China Information System for Disease Control and Prevention. Setting: The study took place at the Zhejiang Provincial Institute of Dermatology in Huzhou, China. Outcome Measures: The research team: (1) used the Geographic Information System software-ArcGIS 10.8 software to draw statistical maps; (2) conducted a spatial-pattern clustering analysis at the district or county level; (3) performed an autocorrelation analysis using Getis-Ord (Gi*) statistics to detect spatial patterns and the hotspots of gonorrhea incidence; and (4) used SaTScan9.7 to analyze the space-time clusters. Results: Zhejiang province reported 85 904 gonorrhea cases from 2016 to 2020, with a male to female ratio of 3.81:1. The average annual incidence rate of gonorrhea was 30.50 per 100 000 individuals in the population, ranging from 22.73 cases to 39.65 cases, and the annual incidence showed a significant downward trend over the five years (χ2 = 16.142, P < .001). The northern and central areas had a higher incidence than the southern area did. Autocorrelation analysis showed that the gonorrhea incidence had a significantly clustered distribution (Moran's I from 0.197 to 0.295, Z score from 4.749 to 6.909, P < .001). The high-high cluster areas were mainly in the urban districts of Hangzhou and some counties and districts of Jiaxing. The Gi* statistics further indicated that the hotspots of gonorrhea were mainly in Hangzhou, Jiaxing, and Huzhou. The Kuldorff's scan identified two clusters, mainly composed of 36 counties or districts in northern Zhejiang, such as Hangzhou and Jiaxing, and central Zhejiang, such as Jinhua and Shaoxing. Conclusions: The gonorrhea incidence rates in northern and central Zhejiang from 2016 to 2020 were higher than those in southern Zhejiang. An area of relatively higher risk for gonorrhea existed mainly in the urban districts of Hangzhou and some counties and districts of Jiaxing, Jinhua, and Shaoxing. In the future, the research team plans to focus on strengthening the prevention and control measures against gonorrhea in those areas.


Asunto(s)
Epidemias , Gonorrea , Humanos , Masculino , Femenino , Gonorrea/epidemiología , Estudios Retrospectivos , Análisis Espacial , China/epidemiología
2.
Int J Mol Sci ; 21(21)2020 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-33137932

RESUMEN

Cadmium (Cd) contamination in soils poses great risks to both agricultural production and human health. Calcium (Ca) is an essential element playing a significant role in protecting plants against Cd toxicity. However, how Ca affects Cd uptake and translocation in rice is still not fully elucidated. In this study, the regulatory role of Ca in Cd uptake and upward translocation was investigated in rice at different growth stages. Our results showed that the supplement of 5 mM Ca significantly reduced Cd uptake by rice roots, because of their competition for Ca-permeable channels as an absorption site and Ca-induced downregulation of OsNRAMP1 and OsNRAMP5. However, Ca application facilitated the upward translocation of Cd by both upregulating OsHMA2 to induce xylem loading of Cd and downregulating OsHMA3 to reduce vacuolar sequestration of Cd. Such contrary results suggested a double-edged role of Ca in regulating root Cd uptake and root-to-shoot Cd translocation in rice. Although it increased Cd content in the aboveground vegetative tissues during the whole growth period, the addition of 5 mM Ca eventually decreased Cd content in rice grains at the ripening stage. All these results suggest that Ca-based amendments possess great potential for the production of low-Cd rice grains.


Asunto(s)
Cadmio/toxicidad , Canales de Calcio/metabolismo , Calcio/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Transporte Biológico , Canales de Calcio/genética , Oryza/efectos de los fármacos , Proteínas de Plantas/genética , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/metabolismo
3.
Environ Pollut ; 265(Pt B): 114979, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32585549

RESUMEN

Understanding of cadmium (Cd) uptake mechanism and development of lower Cd crop genotypes are crucial for combating its phytotoxicity and meeting 70% increase in food demand by 2050. Bio-accumulation of Cd continuously challenges quality of life specifically in regions without adequate environmental planning. Here, we investigated the mechanisms operating in Cd tolerance of two rice genotypes (Heizhan-43 and Yinni-801). Damage to chlorophyll contents and PSII, histochemical staining and quantification of reactive oxygen species (ROS), cell viability and osmolyte accumulation were studied to decipher the interactions between Cd and zinc (Zn) by applying two Cd and two Zn levels (alone as well as combined). Cd2+ and Ca2+ fluxes were also measured by employing sole Cd100 (100 µmol L-1) and Zn50 (50 µmol L-1), and their combination with microelectrode ion flux estimation (MIFE) technique. Cd toxicity substantially reduced chlorophyll contents and maximal photochemical efficiency (Fv/Fm) compared to control plants. Zn supplementation reverted the Cd-induced toxicity by augmenting osmoprotectants and interfering with ROS homeostasis under combined treatments, particularly in Yinni-801 genotype. Fluorescence microscopy indicated a unique pattern of live and dead root cells, depicting more damage with Cd10, Cd15 and Cd15+Zn50. Our results confer that Cd2+ impairs the uptake of Ca2+ whereas, Zn not only competes with Cd2+ but also Ca2+, thereby modifying ion homeostasis in rice plants. This study suggests that exogenous application of Zn is beneficial for rice plants in ameliorating Cd toxicity in a genotype and dose dependent manner by minimizing ROS generation and suppressing collective oxidative damage. The observations confer that Yinni-801 performed better than Heizhan-43 genotype mainly under combined Zn treatments with low-Cd, presenting Zn fortification as a solution to increase rice production.


Asunto(s)
Oryza , Fotosíntesis , Cadmio , Cationes , Homeostasis , Cinética , Calidad de Vida , Especies Reactivas de Oxígeno , Zinc
4.
Front Plant Sci ; 10: 1361, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31737000

RESUMEN

Rice (Oryza sativa) is a staple food that feeds more than half the world population. As rice is highly sensitive to soil salinity, current trends in soil salinization threaten global food security. To better understand the mechanistic basis of salinity tolerance in rice, three contrasting rice cultivars-Reiziq (tolerant), Doongara (moderately tolerant), and Koshihikari (sensitive)-were examined and the differences in operation of key ion transporters mediating ionic homeostasis in these genotypes were evaluated. Tolerant varieties had reduced Na+ translocation from roots to shoots. Electrophysiological and quantitative reverse transcription PCR experiments showed that tolerant genotypes possessed 2-fold higher net Na+ efflux capacity in the root elongation zone. Interestingly, this efflux was only partially mediated by the plasma membrane Na+/H+ antiporter (OsSOS1), suggesting involvement of some other exclusion mechanisms. No significant difference in Na+ exclusion from the mature root zones was found between cultivars, and the transcriptional changes in the salt overly sensitive signaling pathway genes in the elongation zone were not correlated with the genetic variability in salinity tolerance amongst genotypes. The most important hallmark of differential salinity tolerance was in the ability of the plant to retain K+ in both root zones. This trait was conferred by at least three complementary mechanisms: (1) its superior ability to activate H+-ATPase pump operation, both at transcriptional and functional levels; (2) reduced sensitivity of K+ efflux channels to reactive oxygen species; and (3) smaller upregulation in OsGORK and higher upregulation of OsAKT1 in tolerant cultivars in response to salt stress. These traits should be targeted in breeding programs aimed to improve salinity tolerance in commercial rice cultivars.

5.
J Exp Bot ; 69(21): 5279-5291, 2018 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-30099559

RESUMEN

To develop elite crops with low cadmium (Cd), a fundamental understanding of the mechanism of Cd uptake by crop roots is necessary. Here, a new mechanism for Cd2+ entry into rice root cells was investigated. The results showed that Cd2+ influx in rice roots exhibited spatially and temporally dynamic patterns. There was a clear longitudinal variation in Cd uptake along rice roots, with the root tip showing much higher Cd2+ influx and concentration than the root mature zone, which might be due to the much higher expression of the well-known Cd transporter genes OsIRT1, OsNRAMP1, OsNRAMP5, and OsZIP1 in the root tip. Both the net Cd2+ influx and the uptake of Cd in rice roots were highly inhibited by ion channel blockers Gd3+ and TEA+, supplementation of Ca2+ and K+, and the plasma membrane H+-ATPase inhibitor vanadate, with Gd3+ and Ca2+ showing the most inhibitory effects. Furthermore, Ca2+- or Gd3+-induced reduction in Cd2+ influx and Cd uptake did not coincide with the expression of Cd transporter genes, but with that of two Ca channel genes, OsAAN4 and OsGLR3.4. These results indicate that Cd transporters are in part responsible for Cd2+ entry into rice root, and provide a new perspective that the Ca channels OsAAN4 and OsGLR3.4 might play an important role in rice root Cd uptake.


Asunto(s)
Cadmio/farmacología , Canales de Calcio/metabolismo , Membrana Celular/metabolismo , Oryza/metabolismo , Raíces de Plantas/metabolismo , Cadmio/metabolismo , Canales de Calcio/genética , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
Fitoterapia ; 124: 127-131, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29106995

RESUMEN

Azacoccones A-E (1-5), five new aza-epicoccone derivatives, were isolated from the culture of Aspergillus flavipes. Their structures were determined by extensive NMR spectroscopic analyses and the absolute configuration of 5 was determined by electronic circular dichroism (ECD) calculation. Compounds 1-5 are proposed to be generated via a Pictet-Spengler reaction-based biosynthetic route starting from the precursor flavipin. Pictet-Spengler reaction is rarely found in the fungal kingdom, which indicated the distinctive nature of 1-5. Compounds 3 and 5 exhibit significant free radical scavenging activities with IC50 values of 4.0 and 2.4µg/mL, respectively, which are better than the positive control trolox (4.55µg/mL).


Asunto(s)
Aspergillus/química , Polifenoles/aislamiento & purificación , Dicroismo Circular , Depuradores de Radicales Libres/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular
7.
Fitoterapia ; 123: 18-22, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28947170

RESUMEN

An endophytic fungal strain named Trichoderma atroviride was isolated from the bulb of Lycoris radiata. Following cultivation on rice medium, a novel 3-amino-5-hydroxy-5-vinyl-2-cyclopenten-1-one dimer, atrichodermone A (1), a new cyclopentenone derivative, atrichodermone B (2), and a new sesquiterpene, atrichodermone C (3), together with three known cyclopentenone derivatives (4-6) were isolated. Their structures were elucidated by extensive spectroscopic (UV, IR, ECD, HRESIMS, and NMR) data analyses, and absolute configurations of the new compounds were determined by comparing their experimental ECD spectra with structurally similar compounds and computational analyses of their electronic circular dichroism (ECD) spectra. Compounds 1-3 were evaluated for their cytotoxicity against HL60 and U937 cell lines, as well as anti-inflammatory effect against the production of the pro-inflammatory cytokines TNF-α and IL-1ß.


Asunto(s)
Ciclopentanos/química , Sesquiterpenos/química , Trichoderma/química , Animales , Ciclopentanos/aislamiento & purificación , Células HL-60 , Humanos , Interleucina-1beta/metabolismo , Lycoris/microbiología , Ratones , Estructura Molecular , Raíces de Plantas/microbiología , Células RAW 264.7 , Sesquiterpenos/aislamiento & purificación , Factor de Necrosis Tumoral alfa/metabolismo , Células U937
8.
PLoS One ; 12(7): e0180373, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28683101

RESUMEN

BACKGROUND: The green lacewing, Chrysopa pallens Rambur, is one of the most important natural predators because of its extensive spectrum of prey and wide distribution. However, what we know about the nutritional and reproductive physiology of this species is very scarce. RESULTS: By cDNA amplification and Illumina short-read sequencing, we analyzed transcriptomes of C. pallens female adult under starved and fed conditions. In total, 71236 unigenes were obtained with an average length of 833 bp. Four vitellogenins, three insulin-like peptides and two insulin receptors were annotated. Comparison of gene expression profiles suggested that totally 1501 genes were differentially expressed between the two nutritional statuses. KEGG orthology classification showed that these differentially expression genes (DEGs) were mapped to 241 pathways. In turn, the top 4 are ribosome, protein processing in endoplasmic reticulum, biosynthesis of amino acids and carbon metabolism, indicating a distinct difference in nutritional and reproductive signaling between the two feeding conditions. CONCLUSIONS: Our study yielded large-scale molecular information relevant to C. pallens nutritional and reproductive signaling, which will contribute to mass rearing and commercial use of this predaceous insect species.


Asunto(s)
Ingestión de Alimentos/genética , Proteínas de Insectos/genética , Insectos/genética , Reproducción/genética , Transducción de Señal/genética , Transcriptoma , Animales , Agentes de Control Biológico/metabolismo , ADN Complementario/genética , ADN Complementario/metabolismo , Femenino , Privación de Alimentos , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Ontología de Genes , Proteínas de Insectos/metabolismo , Insectos/clasificación , Insectos/crecimiento & desarrollo , Insectos/metabolismo , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Redes y Vías Metabólicas/genética , Anotación de Secuencia Molecular , Filogenia , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Vitelogeninas/genética , Vitelogeninas/metabolismo
9.
Insect Biochem Mol Biol ; 33(9): 889-99, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12915180

RESUMEN

Using specific proteinase inhibitors, we demonstrated that serine proteinases in the tarnished plant bug, Lygus lineolaris, are major proteinases in both salivary glands and gut tissues. Gut proteinases were less sensitive to inhibition than proteinases from the salivary glands. Up to 80% azocaseinase and 90% of BApNAse activities in the salivary glands were inhibited by aprotinin, benzamidine, and PMSF, whereas only 46% azocaseinase and 60% BApNAse activities in the gut were suppressed by benzamidine, leupeptin, and TLCK. The pH optima for azocaseinase activity in salivary glands ranged from 6.2 to 10.6, whereas the pH optima for gut proteinases was acidic for general and alkaline for tryptic proteinases. Zymogram analysis demonstrated that approximately 26-kDa proteinases from salivary glands were active against both gelatin and casein substrates. Three trypsin-like cDNAs, LlSgP2-4, and one trypsin-like cDNA, L1GtP1, were cloned from salivary glands and gut, respectively. Putative trypsin precursors from all cloned cDNAs contained a signal peptide, activation peptide, and conserved N-termini (IVGG). Other structural features included His, Asp, and Ser residues for the catalytic amino acid triad of serine proteinase active sites, residues for the binding pocket, and four pairs of cysteine residues for disulfide bridges. Deduced trypsin-like proteins from LlSgP2, LlSgP3, and LlGtP1 cDNAs shared 98-99% sequence identity with a previously reported trypsin-like precursor, whereas the trypsin-like protein of LlSgP4 shared only 44% sequence identity with all other trypsin-like proteins, indicating multi-trypsin forms are present in L. lineolaris.


Asunto(s)
ADN Complementario/genética , Sistema Digestivo/enzimología , Heterópteros/enzimología , Glándulas Salivales/enzimología , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Benzoilarginina-Nitroanilida/metabolismo , Sitios de Unión/genética , Caseínas/química , Caseínas/metabolismo , Clonación Molecular , Heterópteros/genética , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Filogenia , Homología de Secuencia de Aminoácido , Inhibidores de Serina Proteinasa/farmacología , Especificidad por Sustrato , Tripsina/genética , Tripsina/metabolismo
10.
Insect Biochem Mol Biol ; 32(4): 455-64, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11886780

RESUMEN

Trypsin-like enzymes from the salivary gland complex (SGC) of Lygus hesperus Knight were partially purified by preparative isoelectric focusing (IEF). Enzyme active against Nalpha-benzoyl-L-arginine-p-nitroanilide (BApNA) focused at approximately pH 10 during IEF. This alkaline fraction gave a single activity band when analyzed with casein zymograms. The serine proteinase inhibitors, phenylmethylsulfonyl fluoride (PMSF) and lima bean trypsin inhibitor, completely inhibited or suppressed the caseinolytic activity in the crude salivary gland extract as well as the IEF-purified sample. Chicken egg white trypsin inhibitor also inhibited the IEF-purified sample but was not effective against a major caseinolytic band in the crude salivary gland extract. These data indicated the presence of serine proteinases in the SGC of L. hesperus. Cloning and sequencing of a trypsin-like precursor cDNA provided additional direct evidence for serine proteinases in L. hesperus. The encoded trypsin-like protein included amino acid sequence motifs, which are conserved with five homologous serine proteinases from other insects. Typical features of the putative trypsin-like protein from L. hesperus included residues in the serine proteinase active site (His(89), Asp(139), Ser(229)), conserved cysteine residues for disulfide bridges, residues (Asp(223), Gly(252), Gly(262)) that determine trypsin specificity, and both zymogen signal and activation peptides.


Asunto(s)
Hemípteros/enzimología , Proteínas de Insectos/genética , Serina Endopeptidasas/genética , Tripsina/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cromatografía en Gel/métodos , Clonación Molecular , ADN Complementario , Hemípteros/genética , Focalización Isoeléctrica , Datos de Secuencia Molecular , Filogenia , Glándulas Salivales/enzimología , Homología de Secuencia de Aminoácido , Serina Endopeptidasas/clasificación , Tripsina/clasificación
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