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1.
Food Res Int ; 128: 108778, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31955752

RESUMO

Oolong tea is a partially fermented tea with distinct tastes and aromas. However, the dynamic biochemical changes during oolong tea processing are not well understood. In this study, we performed metabolomics-based profiling of non-volatile and volatile constituents of oolong tea during its entire processing procedures by UPLC-QTOF MS and GC-TOF MS. A step-wise change of tea metabolome was observed, where catechins and oxidized products, flavonol glycosides and amino acids were identified as key discriminate metabolites. The ZuoQing process comprising alternating YaoQing and TanQing steps was deemed most critical for key metabolic transformation. Extensive YaoQing facilitated the oxidative polymerizations of catechins into theaflavins and proanthocyanidins, lowering the astringency in raw tea. Two direct terpene precursors farnesyl pyrophosphate and geranyl pyrophosphate accumulated to high levels during ZuoQing, which provided more substrates for the synthesis of downstream volatile terpenes. Moreover, both YaoQing and prolonged TanQing facilitated the formation of terpenes as well as fatty acid and benzenoid-derived volatiles, which contributed to the fruity and floral fragrances in oolong tea. The fixation step not only converted amino acids into aromatic compounds, but also lowered the amounts of flavonol glycosides, potentially improving the flavor quality of the final tea product. This study provides a comprehensive profile of flavor-related metabolic changes during oolong tea processing and will contribute to better quality control and flavor improvement of oolong tea.

2.
Nature ; 577(7788): 109-114, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31827280

RESUMO

Activation of RIPK1 controls TNF-mediated apoptosis, necroptosis and inflammatory pathways1. Cleavage of human and mouse RIPK1 after residues D324 and D325, respectively, by caspase-8 separates the RIPK1 kinase domain from the intermediate and death domains. The D325A mutation in mouse RIPK1 leads to embryonic lethality during mouse development2,3. However, the functional importance of blocking caspase-8-mediated cleavage of RIPK1 on RIPK1 activation in humans is unknown. Here we identify two families with variants in RIPK1 (D324V and D324H) that lead to distinct symptoms of recurrent fevers and lymphadenopathy in an autosomal-dominant manner. Impaired cleavage of RIPK1 D324 variants by caspase-8 sensitized patients' peripheral blood mononuclear cells to RIPK1 activation, apoptosis and necroptosis induced by TNF. The patients showed strong RIPK1-dependent activation of inflammatory signalling pathways and overproduction of inflammatory cytokines and chemokines compared with unaffected controls. Furthermore, we show that expression of the RIPK1 mutants D325V or D325H in mouse embryonic fibroblasts confers not only increased sensitivity to RIPK1 activation-mediated apoptosis and necroptosis, but also induction of pro-inflammatory cytokines such as IL-6 and TNF. By contrast, patient-derived fibroblasts showed reduced expression of RIPK1 and downregulated production of reactive oxygen species, resulting in resistance to necroptosis and ferroptosis. Together, these data suggest that human non-cleavable RIPK1 variants promote activation of RIPK1, and lead to an autoinflammatory disease characterized by hypersensitivity to apoptosis and necroptosis and increased inflammatory response in peripheral blood mononuclear cells, as well as a compensatory mechanism to protect against several pro-death stimuli in fibroblasts.

3.
BMC Plant Biol ; 19(1): 569, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31856712

RESUMO

BACKGROUND: Seed germination is essential to crop growth and development, and ultimately affects its harvest. It is difficult to breed soybeans low in phytic acid with a higher seed field emergence. Although additional management and selection could overcome the phytate reduction, the mechanisms of seed germination remain unknown. RESULTS: A comparative proteomic analysis was conducted between two low phytic acid (LPA) soybean mutants (TW-1-M and TW-1), both of which had a deletion of 2 bp in the GmMIPS1 gene. However, the TW-1 seeds showed a significantly lower field emergence compared to the TW-1-M. There were 282 differentially accumulated proteins (DAPs) identified between two mutants at the three stages. Among these DAPs, 80 were down-accumulated and 202 were up-accumulated. Bioinformatic analysis showed that the identified proteins were related to functional categories of oxidation reduction, response to stimulus and stress, dormancy and germination processes and catalytic activity. KEGG analysis showed that these DAPs were mainly involved in energy metabolism and anti-stress pathways. Based upon the conjoint analysis of DAPs with the differentially expressed genes (DEGs) previously published among three germination stages in two LPA mutants, 30 shared DAPs/DEGs were identified with different patterns, including plant seed protein, beta-amylase, protein disulfide-isomerase, disease resistance protein, pyrophosphate-fructose 6-phosphate 1-phosphotransferase, cysteine proteinase inhibitor, non-specific lipid-transfer protein, phosphoenolpyruvate carboxylase and acyl-coenzyme A oxidase. CONCLUSIONS: Seed germination is a very complex process in LPA soybean mutants. The TW-1-M and TW-1 showed many DAPs involved in seed germination. The differential accumulation of these proteins could result in the difference of seed field emergence between the two mutants. The high germination rate in the TW-1-M might be strongly attributed to reactive oxygen species-related and plant hormone-related genes. All these findings would help us further explore the germination mechanisms in LPA crops.

4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(4): 664-669, 2019 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-31441269

RESUMO

This study proposed a method to calibrate tube focus spot and the center plane of rotation in computed tomography system. In the method, the tube was rotated to 0° and 180° respectively, and then one metal jig with symmetric windows A and B was scanned at each position under the tube cool and static condition. According to the geometry of tube focus spot, aperture center of the collimator and jig, the distance between tube focus spot and the center plane of rotation were calculated with the X ray transmittance data after denoising, mean value and normalization. To verify the practicability and validity of the method, the tube focus spot in a 16 slices CT system (Brivo CT385, GE, China) was calibrated, and the result after calibration was validated by scanning a polaroid film. The validation result showed that the deviation between tube focal spot and center plane of rotation was 0.02 mm and was in the error range within ± 0.1 mm. The results of this study showed that, as a simple and low-cost design, the method could be used for fast calibration between tube focus spot and the center plane of rotation.


Assuntos
Rotação , Tomografia Computadorizada por Raios X , Calibragem , Raios X
5.
Molecules ; 24(10)2019 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-31109117

RESUMO

White tea (WT) is one of six tea types originally derived from Fujian Province, China. White tea is known for its health-promoting properties. However, the neuroprotective and anti-aggregatory properties of WT against the hallmark toxic Alzheimer's protein, Aß have not been investigated. In this study, WT, green tea (GT), oolong tea (OT) and black tea (BT) were manufactured using tea leaves from the cultivar Camellia sinensis (Jin Guanyin). The protective effects of these tea extracts were then studied under oxidative stress conditions via t-bhp and H2O2 exposure, in addition to Aß treatment using a PC-12 cell model. Each tea type failed to rescue PC-12 cells from either t-bhp or H2O2-mediated toxicity, however each extract exerted significant protection against Aß-evoked neurotoxicity. Results of the Thioflavin T Kinetic (ThT) and TEM assay showed that Aß aggregate formation was inhibited by each tea type. Additionally, TEM also supported the different anti-aggregatory effect of WT by modifying Aß into an amorphous and punctate aggregate morphology. Higher accumulated precedent or potential neuroprotective compounds in WT, including ECG''3Me, 8-C-ascorbyl-EGCG, GABA and Gln, in addition to flavonol or flavone glycosides detected by using UPLC-QTOF-MS and UPLC-QqQ-MS, may contribute to a favourable anti-aggregative and neuroprotective effect of WT against Aß.


Assuntos
Peptídeos beta-Amiloides/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/química , Extratos Vegetais/química , Chá/química , Camellia sinensis/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Peróxido de Hidrogênio/química , Cinética , Neurônios/citologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Análise de Componente Principal/métodos , Espectrometria de Massas em Tandem/métodos , Chá/parasitologia
6.
Fish Shellfish Immunol ; 89: 170-178, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30928663

RESUMO

Peroxiredoxin 6 (Prx6) is an important member of the peroxiredoxin family that plays critical roles in protecting host against the toxicity of oxidative stress and participates in cell signaling. Herein, we report Prx6 gene from red swamp crayfish, Procambarus clarkii. The cDNA fragment of PcPrx6 was 660 bp, encoding a 219 amino acid residues protein. The quantitative real time PCR analysis showed ubiquitous expression of PcPrx6 mRNA in the tested tissues. The challenge with peptidoglycan and Poly I:C remarkably suppressed the mRNA level of PcPrx6 in hepatopancreas at 3, 12, 48 h compared with the PBS control. However, the expression level significantly increased after 36 h of their treatment. The knockdown of PcPrx6 by small interference RNA significantly enhanced the transcript levels of Toll pathway-responsive genes at 24 h. Recombinant PcPrx6 protein was purified using affinity chromatography and analyzed for its biological role. The results revealed that the recombinant PcPrx6 protein manifested the ability to protect supercoiled DNA damage from oxidative stress elicited by mixed function oxidative assay. Altogether, PcPrx6 may have multiple functional roles in the physiology of P. clarkii, since it negatively regulates the Toll signaling transduction and protects supercoiled DNA damage from oxidative stress.


Assuntos
Astacoidea/genética , Astacoidea/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Peroxirredoxina VI/genética , Peroxirredoxina VI/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Cromatografia de Afinidade , Dano ao DNA , DNA Super-Helicoidal/fisiologia , Perfilação da Expressão Gênica , Estresse Oxidativo , Peptidoglicano/farmacologia , Peroxirredoxina VI/química , Filogenia , Poli I-C/farmacologia , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Alinhamento de Sequência
7.
ACS Appl Mater Interfaces ; 11(11): 10777-10784, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30816033

RESUMO

For organic solar cells, the vertical and lateral micro-/nanometer-scale structure in the active layer largely determines the device performance. In this work, the surface and bulk domain size of the photoactive layer are successfully manipulated with a facile two-step spraying method, that is, an ultrathin active layer by high-pressure spraying is deliberately stacked on top of the thick active layer by ultrasonic spraying. Thus, the morphology is effectively optimized with the comprehensive study of optical and electrical characteristics, such as photon absorption, exciton dissociation efficiency, and bimolecular recombination. Moreover, the novel method can be used not only in the fullerene system but also in the nonfullerene system, demonstrating the remarkable universality through this synergy method. This work provides an easy and reliable strategy to improve photovoltaic device performance in the industrial large-area spray-coating process.

8.
J Colloid Interface Sci ; 534: 332-337, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30243173

RESUMO

The rational synthesis of earth-abundant materials with excellent electrocatalytic performances plays a critical role in electrochemical CO2 reduction (ECR) to obtain value-added chemical products or fuels. Here we demonstrate a defective graphene (DG) as such an electrocatalyst candidate via a nitrogen removal method. The graphene with a large amount of topological defects offered abundant catalytically active sites, high electronic conductivity and strong adsorption of CO2. Attributed to these features, the DG exhibited significantly higher electrocatalytic CO2 reduction performances with an excellent faradaic efficiency of ∼84% at -0.6 V vs. reversible hydrogen electrode and a larger current density, compared to pristine graphene, nitrogen-doped graphene and edge-rich graphene. This work suggests a promising method for further designing efficient metal-free electrocatalysts for CO2 reduction.

9.
Biomed Res Int ; 2018: 1470305, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519568

RESUMO

Endophytic actinomycetes are a promising source of novel metabolites with diverse biological activities. Tea plants (Camellia sinensis) produce arsenals of phytochemicals, which are linked to a number of medicinal and nutritional properties. However, a systematic investigation into the abundance and diversity of cultivated actinomycetes residing in tea plants has not been performed. In this study, a total of 46 actinobacteria were recovered from leaf, stem, and root samples of 15 tea cultivars collected in Fujian province, China. Their abundance and diversity were shown to be influenced by both the genotypes and tissue types of tea plants. Based on 16S RNA sequence analysis, these isolates were taxonomically grouped into 11 families and 13 genera, including Streptomyces, Actinomadura, Kribbella, Nocardia, Kytococcus, Leifsonia, Microbacterium, Micromonospora, Mobilicoccus, Mycobacterium, Nocardiopsis, Piscicoccus, and Pseudonocardia. The genus Streptomyces was most prevalent whereas rare genera, Mobilicoccus and Piscicoccus, were reported for the first time to occur as plant endophytes. PCR screening of polyketide synthase genes (PKS-I and PKS-II) and nonribosomal peptide synthetase genes (NRPS), along with antimicrobial assays against a set of bacterial and fungal pathogens, showed that endophytic actinomycetes associated with tea plants have a high potential for producing antimicrobial metabolites. Furthermore, indole acetic acid (IAA) production and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activities were recorded in 93.5% and 21.7% of all isolates, respectively. Overall, these results indicate that endophytic actinomycetes from tea plants represent a valuable source of bioactive metabolites with antibacterial, antifungal, and plant-growth-promoting properties.


Assuntos
Actinobacteria/isolamento & purificação , Antibacterianos/isolamento & purificação , Endófitos/isolamento & purificação , Chá/microbiologia , Actinobacteria/química , Actinobacteria/classificação , Actinobacteria/genética , Aminoácidos Cíclicos/química , Antibacterianos/química , Antibacterianos/farmacologia , China , Endófitos/química , Ácidos Indolacéticos/química , Filogenia , Desenvolvimento Vegetal/efeitos dos fármacos , RNA Ribossômico 16S/genética
10.
Proc Natl Acad Sci U S A ; 115(49): E11542-E11550, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30455308

RESUMO

Fruit growth and ripening are controlled by multiple phytohormones. How these hormones coordinate and interact with each other to control these processes at the molecular level is unclear. We found in the early stages of Fragaria vesca (woodland strawberry) fruit development, auxin increases both widths and lengths of fruits, while gibberellin [gibberellic acid (GA)] mainly promotes their longitudinal elongation. Auxin promoted GA biosynthesis and signaling by activating GA biosynthetic and signaling genes, suggesting auxin function is partially dependent on GA function. To prevent the repressive effect of abscisic acid (ABA) on fruit growth, auxin and GA suppressed ABA accumulation during early fruit development by activating the expression of FveCYP707A4a encoding cytochrome P450 monooxygenase that catalyzes ABA catabolism. At the onset of fruit ripening, both auxin and GA levels decreased, leading to a steep increase in the endogenous level of ABA that drives fruit ripening. ABA repressed the expression of FveCYP707A4a but promoted that of FveNCED, a rate-limiting step in ABA biosynthesis. Accordingly, altering FveCYP707A4a expression changed the endogenous ABA levels and affected FveNCED expression. Hence, ABA catabolism and biosynthesis are tightly linked by feedback and feedforward loops to limit ABA contents for fruit growth and to quickly increase ABA contents for the onset of fruit ripening. These results indicate that FveCYP707A4a not only regulates ABA accumulation but also provides a hub to coordinate fruit size and ripening times by relaying auxin, GA, and ABA signals.


Assuntos
Ácido Abscísico/metabolismo , Fragaria/metabolismo , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Ácidos Indolacéticos , Redes e Vias Metabólicas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
11.
Biochem Biophys Res Commun ; 504(4): 949-956, 2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30220545

RESUMO

BACKGROUND: Podocyte apoptosis is important mechanism that leading to proteinuria in Diabetic nephropathy (DN), but the underling mechanisms that cause podocyte apoptosis in DN are not very clear. We have recently demonstrated that RhoA, a small GTPase protein, effectively protected podocyte apoptosis induced by LPS and ADR in vitro. However, the potential role of RhoA in DN is unknown. METHODS AND RESULTS: Conditionally immortalized mouse podocyte cells, C57BL/KsJ, db/db diabetic mice, and renal biopsies from patients with DN were used for study. The treatment of podocytes with high glucose (HG) for 48h significantly induced cell apoptosis and decreased RhoA expression and its activity. The expression of RhoA was also decreased in glomerular podocytes of db/db mice and patients with DN. Knockdown of RhoA by siRNA contributed in the apoptosis of podocyte and induced proteinuria in db/db mice. Beyond the increased pro-apoptotic Bax and the decreased anti-apoptotic Bcl-2, RhoA knockdown also inhibited the expression of a nuclear protein of YAP in podocyte. Over expression active form of YAP completely abolished the apoptosis of podocyte induced by RhoA knockdown. CONCLUSION: RhoA plays a critical role in DN probably by mediating the podocyte apoptosis through YAP. RhoA may be a novel molecular target for the treatment of DN.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Nefropatias Diabéticas/patologia , Fosfoproteínas/metabolismo , Podócitos/patologia , Proteínas rho de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apoptose/fisiologia , Proteínas de Ciclo Celular , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/metabolismo , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fosfoproteínas/genética , Podócitos/metabolismo , Proteínas rho de Ligação ao GTP/genética
12.
Wei Sheng Yan Jiu ; 47(3): 432-436, 2018 May.
Artigo em Chinês | MEDLINE | ID: mdl-30082012

RESUMO

OBJECTIVE: To study hypoglycemic effects of different mulberry leaf extracts on diabetic mice. METHODS: STZ-induced diabetic mice were intragastricly administrated with different mulberry leaf extracts( water extracts: 800 mg/kg, ethanol extracts: 500 mg/kg, water extracts + ethanol extracts: low dose 150 mg/kg, high dose300 mg/kg) and positive control group( melbine: 227. 5 mg/kg). Four weeks later, serum glucose levels, insulin levels, antioxidase activities were tested. Liver and pancreas pathological changes were observed by HE staining. RESULTS: Compared with model group, each mulberry leaf extracts group could decrease serum glucose and insulin levels and increase antioxidase activities. The mixture of water extracts and ethanol extracts at high dose showed the most obvious effects. In this group, serum glucose levels, insulin levels, insulin resistance index and insulin sensitivity index were 61. 0%, 64. 1%, 42. 9% and 1. 18 times of those in the model group( P < 0. 05), and no significant differences were found between this group and the positive group( P > 0. 05). CONCLUSION: The mixture of mulberry leaf water and ethanol extracts showed synergistic hypoglycemic effects by increasing antioxidase activities, repairing pancrea and liver oxidative damages, and improving insulin resistance status.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Extratos Vegetais , Folhas de Planta/química , Animais , Insulina , Resistência à Insulina , Camundongos , Morus
13.
Molecules ; 23(7)2018 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-30037120

RESUMO

Tea plants produce extremely diverse and abundant specialized metabolites, the types and levels of which are developmentally and environmentally regulated. However, little is known about how developmental cues affect the synthesis of many of these molecules. In this study, we conducted a comparative profiling of specialized metabolites from six different tissues in a premium oolong tea cultivar, Tieguanyin, which is gaining worldwide popularity due to its uniquely rich flavors and health benefits. UPLC-QTOF MS combined with multivariate analyses tentatively identified 68 metabolites belonging to 11 metabolite classes, which exhibited sharp variations among tissues. Several metabolite classes, such as flavonoids, alkaloids, and hydroxycinnamic acid amides were detected predominantly in certain plant tissues. In particular, tricoumaroyl spermidine and dicoumaroyl putrescine were discovered as unique tea flower metabolites. This study offers novel insights into tissue-specific specialized metabolism in Tieguanyin, which provides a good reference point to explore gene-metabolite relationships in this cultivar.


Assuntos
Metaboloma , Metabolômica , Chá/metabolismo , Cromatografia Líquida de Alta Pressão , Redes e Vias Metabólicas , Metabolômica/métodos , Especificidade de Órgãos , Fenótipo , Compostos Fitoquímicos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Chá/química
14.
ACS Appl Mater Interfaces ; 10(26): 22485-22494, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29893117

RESUMO

Extremely simplified one-step roll-to-roll slot-die-printed flexible indium tin oxide (ITO)-free polymer solar cells (PSCs) are demonstrated based on the ternary blends of electron-donor polymer thieno[3,4- b]thiophene/benzodithiophene, electron-acceptor fullerene [6,6]-phenyl-C71-butyric acid methyl ester, and electron-extracting polymer poly[(9,9-bis(3'-( N, N-dimethylamino)propyl)-2,7-fluorene)- alt-2,7-(9,9-dioctylfluorene)] (PFN) at room temperature (RT) in ambient air. The flexible ITO-free PSC exhibits a comparable power conversion efficiency (PCE) with the device employing complicated two-step slot-die printing (5.29% vs 5.41%), which indicates that PFN molecules can migrate from the ternary nanocomposite toward the Ag cathode via vertical self-assembly during the one-step slot-die printing process in air. To confirm the migration of PFN, the morphology and elemental analysis as well as charge transport of different active layers are investigated by the in situ transient film drying process, transmission electron microscopy, atomic force microscopy, contact angle and surface energy, X-ray photoelectron spectroscopy, scanning electron microscopy, impedance spectroscopy, transient photovoltage and transient photocurrent, and laser-beam-induced current. Moreover, the good air and mechanical stability of the flexible device with a decent PCE achieved in 1 cm2 PSCs at RT in air suggests the feasibility of energy-saving and time-saving one-step slot-die printing to large-scale roll-to-roll manufacture in the future.

15.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(2): 297-300, 2018 04 25.
Artigo em Chinês | MEDLINE | ID: mdl-29745537

RESUMO

One algorithm is designed to implement longitudinal auto-tracking of the the detector on X-ray in the digital radiography system (DR) with manual collimator. In this study, when the longitudinal length of field of view (LFOV) on the detector is coincided with the longitudinal effective imaging size of the detector, the collimator half open angle ( Ψ), the maximum centric distance ( emax) between the center of X-ray field of view and the projection center of the focal spot, and the detector moving distance for auto-traking can be calculated automatically. When LFOV is smaller than the longitudinal effective imaging size of the detector by reducing Ψ, the emax can still be used to calculate the detector moving distance. Using this auto-tracking algorithm in DR with manual collimator, the tested results show that the X-ray projection is totally covered by the effective imaging area of the detector, although the center of the field of view is not aligned with the center of the effective imaging area of the detector. As a simple and low-cost design, the algorithm can be used for longitudinal auto-tracking of the detector on X-ray in the manual collimator DR.

16.
Medicine (Baltimore) ; 97(17): e0451, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29702997

RESUMO

RATIONALE: Anuria is a severe symptom indicating severe kidney damage. Patient recovery from prolonged anuria is rarely reported. PATIENT CONCERNS: A 15-year-old boy received gender- and weight-mismatch heart transplantation (HT) due to dilated cardiomyopathy. He developed severe hypotension, and heart failure 24 hours after surgery, which were relieved by preload reduction treatments. Although, routine examinations did not show any abnormalities in renal function before surgery, anuria occurred 4 days after preload reduction treatments (24-hour urine volume was 23 mL). DIAGNOSIS: The patient was diagnosed with acute kidney injury (AKI). INTERVENTIONS: He was admitted to continuous renal replacement therapy (CRRT) or hemodialysis. OUTCOMES: Surprisingly, his urine volume was gradually, and miraculously, restored to more than 1000 mL/24 hours after over 300 days of anuria. Hemodialysis was not needed in the twentieth month after surgery. Moreover, he partially, recovered renal function. LESSONS: This case indicates the likelihood of recovery from long-term anuria.


Assuntos
Lesão Renal Aguda/etiologia , Anuria/etiologia , Transplante de Coração/efeitos adversos , Lesão Renal Aguda/terapia , Adolescente , Anuria/terapia , Humanos , Doença Iatrogênica , Masculino , Diálise Renal
17.
mBio ; 9(1)2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29463660

RESUMO

Enteroaggregative Escherichia coli (EAEC) is an important diarrheal pathogen and a cause of both acute and chronic diarrhea. It is a common cause of pediatric bacterial diarrhea in developing countries. Despite its discovery in 1987, the intestinal tropism of the pathogen remains unknown. Cell lines used to study EAEC adherence include the HEp-2, T-84, and Caco-2 lines, but they exhibit abnormal metabolism and large variations in gene expression. Animal models either do not faithfully manifest human clinical symptoms or are cumbersome and expensive. Using human intestinal enteroids derived from all four segments of the human intestine, we find that EAEC demonstrates aggregative adherence to duodenal and ileal enteroids, with donor-driven differences driving a sheet-like and layered pattern. This contrasts with the colon, where segment-specific tropisms yielded a mesh-like adherence pattern dominated by interconnecting filaments. Very little to no aggregative adherence to jejunal enteroids was observed, regardless of the strain or donor, in contrast to a strong duodenal association across all donors and strains. These unique patterns of intestinal segment- or donor-specific adherence, but not the overall numbers of associated bacteria, were dependent on the major subunit protein of aggregative adherence fimbriae II (AafA), implying that the morphology of adherent clusters and the overall intestinal cell association of EAEC occur by different mechanisms. Our results suggest that we must give serious consideration to inter- and intrapatient variations in what is arguably the first step in pathogenesis, that of adherence, when considering the clinical manifestation of these infections.IMPORTANCE EAEC is a leading cause of pediatric bacterial diarrhea and a common cause of diarrhea among travelers and immunocompromised individuals. Heterogeneity in EAEC strains and lack of a good model system are major roadblocks to the understanding of its pathogenesis. Utilizing human intestinal enteroids to study the adherence of EAEC, we demonstrate that unique patterns of adherence are largely driven by unidentified factors present in different intestinal segments and from different donors. These patterns are also dependent on aggregative adherence fimbriae II encoded by EAEC. These results imply that we must also consider the contribution of the host to understand the pathogenesis of EAEC-induced inflammation and diarrhea.


Assuntos
Aderência Bacteriana , Escherichia coli/fisiologia , Intestinos/microbiologia , Tropismo Viral , Adesinas de Escherichia coli/genética , Adesinas de Escherichia coli/metabolismo , Escherichia coli/genética , Humanos , Técnicas de Cultura de Órgãos
18.
Fish Shellfish Immunol ; 75: 216-222, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29408672

RESUMO

Peroxiredoxin (Prx) family members play a key role in host defense against oxidative stress, and modulate immune responses following microbial infection. Here, we cloned and characterized Procambarus clarkii Prx4 (Peroxiredoxin 4) cDNA, a regulator of oxidative stress and its expression analysis upon lipopolysaccharide (LPS) and polyriboinosinic polyribocytidylic acid (Poly I:C) infection. The cDNA fragment of PcPrx4 was 744 bp in length, encoding a putative protein of 248 amino acid residues. Real-time quantitative reverse transcription-PCR (qRT-PCR) analysis showed that the PcPrx4 was expressed in all the examined tissues, and it was highest in the hepatopancreas followed by the hemocytes and gill. The challenge with LPS and Poly I:C significantly up-regulated the expression of PcPrx4 in hepatopancreas, hemocytes and gill when compared with the control. Recombinant PcPrx4 protein was used to investigate the antioxidant function in vitro by mixed-function oxidase assay. The results demonstrated a dose-dependent inhibition of DNA damage by rPcPrx4 protein. Altogether, our results imply that PcPrx4 is implicated in defense against microbial pathogens and oxidants in P. clarkii.


Assuntos
Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Penaeidae/genética , Penaeidae/imunologia , Peroxirredoxinas/genética , Peroxirredoxinas/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Perfilação da Expressão Gênica , Lipopolissacarídeos/farmacologia , Peroxirredoxinas/química , Filogenia , Poli I-C/farmacologia , Distribuição Aleatória , Proteínas Recombinantes/genética , Alinhamento de Sequência
19.
Molecules ; 23(2)2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29364152

RESUMO

Wuyi Rock tea, well-recognized for rich flavor and long-lasting fragrance, is a premium subcategory of oolong tea mainly produced in Wuyi Mountain and nearby regions of China. The quality of tea is mainly determined by the chemical constituents in the tea leaves. However, this remains underexplored for Wuyi Rock tea cultivars. In this study, we investigated the leaf metabolite profiles of 14 major Wuyi Rock tea cultivars grown in the same producing region using UPLC-QTOF MS and UPLC-QqQ MS with data processing via principal component analysis and cluster analysis. Relative quantitation of 49 major metabolites including flavan-3-ols, proanthocyanidins, flavonol glycosides, flavone glycosides, flavonone glycosides, phenolic acid derivatives, hydrolysable tannins, alkaloids and amino acids revealed clear variations between tea cultivars. In particular, catechins, kaempferol and quercetin derivatives were key metabolites responsible for cultivar discrimination. Information on the varietal differences in the levels of bioactive/functional metabolites, such as methylated catechins, flavonol glycosides and theanine, offers valuable insights to further explore the nutritional values and sensory qualities of Wuyi Rock tea. It also provides potential markers for tea plant fingerprinting and cultivar identification.


Assuntos
Metaboloma , Metabolômica , Chá/química , Aminoácidos/análise , Aminoácidos/química , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Espectrometria de Massas , Metabolômica/métodos , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química
20.
Int J Mol Med ; 41(1): 77-86, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29115390

RESUMO

The development of diabetes mellitus (DM) is accompanied by hyperglycemia-induced oxidative stress. Hyperoside is a major bioactive component in Zanthoxylum bungeanum leaves (HZL) and is a natural antioxidant. However, the effects of HZL on DM and its mechanisms of action remain undefined. The present study evaluated the anti-hypoglycemic and hepatocyte-protective effects of HZL in mice with diabetes induced by a high-carbohydrate/high-fat diet (HFD) and alloxan. We also aimed to eludicate the underlying mechanisms. Our resutls demonstrated that the administration of HZL significantly reduced body weight gain, serum glucose levels and insulin levels in diabetic mice compared with the vehicle-treated mice. In addition, the levels of dyslipidemia markers including total cholesterol, triglyceride and low­density lipoprotein cholesterol in the HFD-treated mice were markedly decreased. Further experiments using hepatocytes from mice revealed that HZL significantly attenuated liver injury associated with DM compared with vehicle treatment, as evidenced by lower levels of alanine aminotransferase and aspartate aminotransferase in serum and by lower levels of lipid peroxidation, nitric oxide content and inducible nitric oxide synthase activity in liver tissues. Nuclear factor-κB (NF-κB) and mitogen-associated protein kinase (MAPK) signaling pathways were investigated to elucidate the molecular mechanisms responsible for the protective effects of HZL against diabetic liver injury. The results indicated that HZL inhibited the phosphorylation of p65/NF-κB, MAPK (including p38, JNK and ERK1/2) and activating transcription factor 3 protein expression, with an additional suppression of Bax, cytochrome c, caspase-9 and caspase-3 in the liver tissues of diabetic mice. Taken together, our findings suggest that HZL, which was effective in inhibiting oxidative stress-related pathways may be beneficial for use in the treatment of DM.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Quercetina/análogos & derivados , Animais , Diabetes Mellitus/genética , Diabetes Mellitus/patologia , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , NF-kappa B/genética , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química , Quercetina/administração & dosagem , Quercetina/química , Zanthoxylum/química , Proteínas Quinases p38 Ativadas por Mitógeno/genética
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