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1.
Proc Natl Acad Sci U S A ; 120(1): e2209856120, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36574653

RESUMEN

Breast cancer (BC) is a complex disease comprising multiple distinct subtypes with different genetic features and pathological characteristics. Although a large number of antineoplastic compounds have been approved for clinical use, patient-to-patient variability in drug response is frequently observed, highlighting the need for efficient treatment prediction for individualized therapy. Several patient-derived models have been established lately for the prediction of drug response. However, each of these models has its limitations that impede their clinical application. Here, we report that the whole-tumor cell culture (WTC) ex vivo model could be stably established from all breast tumors with a high success rate (98 out of 116), and it could reassemble the parental tumors with the endogenous microenvironment. We observed strong clinical associations and predictive values from the investigation of a broad range of BC therapies with WTCs derived from a patient cohort. The accuracy was further supported by the correlation between WTC-based test results and patients' clinical responses in a separate validation study, where the neoadjuvant treatment regimens of 15 BC patients were mimicked. Collectively, the WTC model allows us to accomplish personalized drug testing within 10 d, even for small-sized tumors, highlighting its potential for individualized BC therapy. Furthermore, coupled with genomic and transcriptomic analyses, WTC-based testing can also help to stratify specific patient groups for assignment into appropriate clinical trials, as well as validate potential biomarkers during drug development.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Perfilación de la Expresión Génica , Biomarcadores , Técnicas de Cultivo de Célula , Microambiente Tumoral
2.
J Cell Mol Med ; 28(1): e18022, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37929660

RESUMEN

Long noncoding RNAs (lncRNAs) play critical roles in the carcinogenesis and progression of cancers. However, the role and mechanism of the pseudogene lncRNA PIN1P1 in gastric carcinoma remain unclear. The expression and effects of lncRNA PIN1P1 in gastric cancer were investigated. The transcriptional regulation of CREB1 on PIN1P1 was determined by ChIP and luciferase assays. The mechanistic model of PIN1P1 in gastric cancer was further explored by RNA pull-down, RIP and western blot analysis. PIN1P1 was overexpressed in gastric cancer tissues, and upregulated PIN1P1 predicted poor prognosis in patients. CREB1 was directly combined with the promoter region of PIN1P1 to promote the transcription of PIN1P1. CREB1-mediated enhanced proliferation, migration and invasion could be partially reversed by downregulation of PIN1P1. Overexpressed PIN1P1 promoted the proliferation, migration and invasion of gastric cancer cells, whereas decreased PIN1P1 showed the opposite effects. PIN1P1 directly interacted with YBX1 and promoted YBX1 protein expression, leading to upregulation of PIN1, in which E2F1 may be involved. Silencing of YBX1 during PIN1P1 overexpression could partially rescue PIN1 upregulation. PIN1, the parental gene of PIN1P1, was elevated in gastric cancer tissues, and its upregulation was correlated with poor patient outcomes. PIN1 facilitated gastric cancer cell proliferation, migration and invasion. To sum up, CREB1-activated PIN1P1 could promote gastric cancer progression through YBX1 and upregulating PIN1, suggesting that it is a potential target for gastric cancer.


Asunto(s)
ARN Largo no Codificante , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , ARN Largo no Codificante/genética , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Movimiento Celular/genética , Proteína 1 de Unión a la Caja Y/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Peptidilprolil Isomerasa de Interacción con NIMA/genética , Peptidilprolil Isomerasa de Interacción con NIMA/metabolismo
3.
Anal Chem ; 95(11): 4871-4879, 2023 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-36878693

RESUMEN

The 18O/16O ratio of α-cellulose in land plants has proved of interest for climate, environmental, physiological, and metabolic studies. Reliable application of such a ratio may be compromised by the presence of hemicellulose impurities in the α-cellulose product obtainable with current extraction methods, as the impurities are known to be isotopically different from that of the α-cellulose. We first compared the quality of hydrolysates of "α-cellulose products" obtained with four representative extraction methods (Jayme and Wise; Brendel; Zhou; Loader) and quantified the hemicellulose-derived non-glucose sugars in the α-cellulose products from 40 land grass species using gas chromatography-mass spectrometry (GC/MS). Second, we performed compound-specific isotope analysis of the hydrolysates using GC/Pyrolysis/IRMS. These results were then compared with the bulk isotope analysis using EA/Pyrolysis/IRMS of the α-cellulose products. We found that overall, the Zhou method afforded the highest purity α-cellulose as judged by the minimal presence of lignin and the second-lowest presence of non-glucose sugars. Isotopic analysis then showed that the O-2-O-6 of the α-cellulose glucosyl units were all depleted in 18O by 0.0-4.3 mUr (average, 1.9 mUr) in a species-dependent manner relative to the α-cellulose products. The positive isotopic bias of using the α-cellulose product instead of the glucosyl units stems mainly from the fact that the pentoses that dominate hemicellulose contamination in the α-cellulose product are relatively enriched in 18O (compared to hexoses) as they inherit only the relatively 18O-enriched O-2-O-5 moiety of sucrose, the common precursor of pentoses and hexoses in cellulose, and are further enriched in 18O by the (incomplete) hydrolysis.


Asunto(s)
Celulosa , Embryophyta , Isótopos de Oxígeno/análisis , Celulosa/química , Sacarosa , Embryophyta/metabolismo , Pentosas , Isótopos de Carbono
4.
Gastric Cancer ; 26(2): 250-263, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36602696

RESUMEN

BACKGROUND: Gastric cancer is the fourth leading cause of cancer-related deaths worldwide. And patient outcomes are poor due to tumor relapse and metastasis. To develop new therapeutic strategies, it is of great importance to explore the mechanism underlying the progression of gastric cancer. METHODS: Primary gastric cancer samples with lymph node metastases (LNM) and without LNM were subjected to mRNA microarray assay. The differentially expressed genes were confirmed by RT-qPCR. HRCT1 protein expression was further detected using an immunohistochemistry (IHC) assay. In vitro and in vivo assays were performed to investigate the role of HRCT1 in tumor invasion, metastasis, and proliferation. The expressions of the downstream target genes of HRCT1 were detected by microarray, RT-qPCR and Western blot assays. Dual-luciferase reporter and Western blot assays were carried out to identify miRNAs target to HRCT1. RESULTS: HRCT1 was upregulated in gastric cancer, and high expression of HRCT1 was associated with poor overall survival (OS) and disease-free survival (DFS). Moreover, HRCT1protein expression was an independent predictor for poor OS and DFS. HRCT1 could promote gastric cancer cells' migration, invasion, and proliferation in vitro as well as tumor metastasis and growth in vivo. Notably, our data showed that HRCT1 promoted gastric cancer progression by activating the ERBB2-MAPK signaling pathway. At least partially, the expression of HRCT1 could be negatively regulated by miR-124-3p. CONCLUSIONS: The upregulated expression of HRCT1 predicts poor survival for patients with gastric cancer. HRCT1 promotes tumor progression by activating the ERBB2-MAPK pathway. HRCT1, negatively regulated by miR-124-3p, may be a potential therapeutic target for patients with gastric cancer.


Asunto(s)
MicroARNs , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patología , Proliferación Celular/genética , Línea Celular Tumoral , MicroARNs/genética , Transducción de Señal , Metástasis Linfática , Regulación Neoplásica de la Expresión Génica , Movimiento Celular/genética , Receptor ErbB-2/metabolismo
5.
Molecules ; 28(5)2023 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-36903616

RESUMEN

The first total synthesis of lineaflavones A, C, D, and their analogues has been accomplished. The key synthetic steps include aldol/oxa-Michael/dehydration sequence reactions to assemble the tricyclic core, Claisen rearrangement and Schenck ene reaction to construct the key intermediate, and selective substitution or elimination of tertiary allylic alcohol to obtain natural compounds. In addition, we also explored five new routes to synthesize fifty-three natural product analogues, which can contribute to a systematic structure-activity relationship during biological evaluation.


Asunto(s)
Productos Biológicos , Relación Estructura-Actividad , Estereoisomerismo
6.
Curr Psychol ; : 1-10, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36855644

RESUMEN

Since the pace of population aging is getting faster than in the past, the population aging has been a serious social concern. The Quality of life (QOL) of the older adults, especially the oldest old, and their mental health problems need more public attention, for the purpose of enhancing their late well-being. Therefore, the current study aims to investigate the longitudinal relationship between loneliness to quality of life and mental health problems, considering the moderation effect of mindfulness among the oldest old. A total of 457 Chinese oldest-old completed questionnaires measuring mindfulness, loneliness, QOL, and mental health problems at baseline, and completed QOL and mental health problems again at six-month follow-up. Results showed that the longitudinal positive association between loneliness and mental health problems was significant (r = .401, p < .01). Nevertheless, loneliness was positively correlated with QOL (r = .242, p < .01). Additionally, mindfulness significantly moderated the association between loneliness and mental health problems. Specifically, higher mindfulness was associated with a weaker longitudinal relationship between loneliness and mental health problems. However, mindfulness did not moderate the relationship between loneliness and QOL. These findings indicated that loneliness can be a risk factor of mental health problems, and mindfulness can buffer the adverse effect of loneliness on mental health problems among the oldest old. Limitations and implications were discussed.

7.
J Org Chem ; 87(5): 3468-3481, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35080889

RESUMEN

A highly efficient Rh(III)-catalyzed C-H diamidation and diamidation/intramolecular cyclization of N-iminopyridinium ylides with dioxazolones has been developed, providing diamidated products and benzoxazinone products in good to excellent yields. Notably, the tunable selectivity of this reaction can be controlled by simply switching the solvent and the temperature. This reaction features operational simplicity, a broad substrate scope, and a good functional group tolerance.

8.
Angew Chem Int Ed Engl ; 61(52): e202212589, 2022 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-36328962

RESUMEN

Expanding the enzymatic toolbox for the green synthesis of valuable molecules is still of high interest in synthetic chemistry and the pharmaceutical industry. Chiral thiiranes are valuable sulfur-containing heterocyclic compounds, but relevant methods for their enantioselective synthesis are limited. Herein, we report a biocatalytic thionation strategy for the enantioselective synthesis of thiiranes, which was developed based on the halohydrin dehalogenase (HHDH)-catalyzed enantioselective ring-opening reaction of epoxides with thiocyanate and a subsequent nonenzymatic rearrangement process. A novel HHDH was identified and engineered for enantioselective biocatalytic thionation of various aryl- and alkyl-substituted epoxides on a preparative scale, affording the corresponding thiiranes in up to 43 % isolated yield and 98 % ee. Large-scale synthesis and useful transformations of chiral thiiranes were also performed to demonstrate the utility and scalability of the biocatalytic thionation strategy.


Asunto(s)
Compuestos Epoxi , Compuestos Epoxi/química , Estereoisomerismo , Biocatálisis
9.
Br J Cancer ; 122(12): 1825-1836, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32336754

RESUMEN

BACKGROUND: Accumulating evidence demonstrated that long noncoding RNAs (lncRNAs) played important regulatory roles in many cancer types. However, the role of lncRNAs in gastric cancer (GC) progression remains unclear. METHODS: RT-qPCR assay was performed to detect the expression of HNF1A-AS1 in gastric cancer tissues and the non-tumourous gastric mucosa. Overexpression and RNA interference approaches were used to investigate the effects of HNF1A-AS1 on GC cells. Insight into competitive endogenous RNA (ceRNA) mechanisms was gained via bioinformatics analysis, luciferase assays and an RNA-binding protein immunoprecipitation (RIP) assay, RNA-FISH co-localisation analysis combined with microRNA (miRNA)-pulldown assay. RESULTS: This study displayed that revealed expression of HNF1A-AS1 was associated with positive lymph node metastasis in GC. Moreover, HNF1A-AS1 significantly promoted gastric cancer invasion, metastasis, angiogenesis and lymphangiogenesis in vitro and in vivo. In addition, HNF1A-AS1 was demonstrated to function as a ceRNA for miR-30b-3p. HNF1A-AS1 abolished the function of the miRNA-30b-3p and resulted in the derepression of its target, PIK3CD, which is a core oncogene involved in the progression of GC. CONCLUSION: This study demonstrated that HNF1A-AS1 worked as a ceRNA and promoted PI3K/AKT signalling pathway-mediated GC metastasis by sponging miR-30b-3p, offering novel insights of the metastasis mechanism in GC.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Neoplasias Gástricas/patología , Anciano , Animales , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Desnudos , MicroARNs/genética , Persona de Mediana Edad , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Largo no Codificante/genética , Transducción de Señal/fisiología , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
10.
Anal Chem ; 92(11): 7462-7470, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32365292

RESUMEN

Information about plant photosynthetic carbon assimilation, physiology, and biochemistry is locked in the 18O/16O ratios of the individual positions of higher plants carbohydrates but is under-utilized, because of the difficulty of making these determinations. We report the extension of the wet chemistry approach we used to access the 18O/16O ratio of O-3 of glucose with a novel GC/Pyrolysis/IRMS-based method, to determine the 18O/16O ratios of O-4, O-5, and O-6. The O atoms (OH groups) at positions 1, 2, 5, and 6 of glucose were protected by acetonation (converting to 1,2;5,6-di-O-isopropylidene-glucofuranose, DAGF). The DAGF was then converted to 6-bromo-6-deoxy-1,2;3,5-di-O-isopropylidene-glucofuranose (6-bromoDAGF) with the simultaneous removal of O-6 with N-bromosuccinimide and triphenylphosphine. The DAGF was also methylated at O-3 with CH3I under the catalysis of NaH to 3-methylDAGF, which was then deacetonated to 1,2-O-isopropylidene-3-O-methyl-glucofuranose (3-methylMAGF). O-5 and O-6 were then removed as a whole from 3-methylMAGF by I2 oxidization under the catalysis of Ph3P and imidazole. Isotope mass balance was then applied to calculate the 18O/16O of O-5 and O-6 as a whole and O-6, respectively. Sampling at different stages of substrate conversion to product and applying a Rayleigh-type fractionation model were employed, when quantitative conversion of substrate was unachievable to calculate the δ18O of the converted substrate. Quantitative conversion of glucose with phenylhydrazine to phenylglucosazone also allowed for the calculation of δ18O2 by applying isotope mass balance between the two. A C4 starch-derived glucose intramolecular δ18O profile is now determined: O-3 is relatively enriched (by 12.16 mUr), O-4 is relatively depleted (by 20.40-31.11 mUr), and O-2 is marginally enriched (by 2.40 mUr) against the molecular average.


Asunto(s)
Carbohidratos/análisis , Oxígeno/química , Cromatografía de Gases y Espectrometría de Masas , Estructura Molecular , Isótopos de Oxígeno
11.
Anal Chem ; 92(18): 12216-12225, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32786439

RESUMEN

The 18O/16O (and 15N/14N) ratio of natural nitrate (NO3-) and nitrite (NO2-) can be used to extract valuable information about their source and fate as environmental contaminants, their metabolism as macronutrients in plants and animals, and their behavior in the N biogeochemical cycle. We developed an accurate, precise, sensitive (minimum sample size: 0.2 µg NO3--equivalent), and reliable (minimal oxygen exchange, loss, or gain) method to selectively isolate and purify nitrate and nitrite from natural water, soil, air, and plant materials by strong anion exchange (SAX) for low- to normal-salinity samples or strong cation exchange (SCX) for high-salinity samples, followed by quantitative conversion to their respective benzyl esters, which can be separated and individually analyzed for δ18O (and potentially δ15N) by gas chromatography (GC)/pyrolysis/GC/isotope-ratio mass spectrometry (IRMS). The method compares favorably with the currently popular bacterial denitrification and chemical reduction methods, in terms of sensitivity and reliability, and has the potential to simultaneously measure δ15N and δ18O of nitrate and nitrite from natural samples of various origins.


Asunto(s)
Nitratos/análisis , Nitritos/análisis , Cromatografía de Gases , Espectrometría de Masas , Isótopos de Nitrógeno , Isótopos de Oxígeno , Pirólisis
12.
Neurobiol Learn Mem ; 169: 107155, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31904547

RESUMEN

Diabetic rats display cognition impairments accompanied by activation of NF-κB signalling and increased Aß expression. Ghrelin has been suggested to improve cognition in diabetic rats. In this study, we investigated the role of ghrelin on cognition and NF-κB mediated Aß production in diabetic rats. A diabetic rat model was established with streptozotocin (STZ) injection, and diabetic rats were intracerebroventricularly administered with ghrelin or (D-lys3)-GHRP-6 (DG). Our results showed that diabetic rats had cognition impairment in the Morris water maze test, accompanied by the higher expression of Aß in the hippocampus. Western blot analysis showed that diabetic rats exhibited significantly decreased levels of GHSR-1a and protein phosphatase 1 (PP1) in the hippocampus and increased activation of the IKK/NF-κB/BACE1 pathway. Chronic ghrelin administration upregulated hippocampal PP1 expression, suppressed IKK/NF-κB/BACE1 mediated Aß production, and improved cognition in STZ-induced diabetic rats. These effects were reversed by DG. Then, primary rat hippocampal neurons were isolated and treated with high glucose, followed by Ghrelin and DG, PP1 or IKK. Similar to the in vivo results, high glucose suppressed the expression levels of GHSR-1a and PP1, activated the IKK/NF-κB/BACE1 pathway, increased Aß production. Ghrelin suppressed IKK/NF-κB/BACE1 induced Aß production. This improvement was reversed by DG and a PP1 antagonist and was enhanced by the IKK antagonist. Our findings indicated that chronic ghrelin administration can suppress IKK/NF-κB/BACE1 mediated Aß production in primary neurons with high glucose treatment and improve the cognition via PP1 upregulation in diabetic rats.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Cognición/fisiología , Diabetes Mellitus Experimental/metabolismo , Ghrelina/metabolismo , Neuronas/metabolismo , Proteína Fosfatasa 1/metabolismo , Transducción de Señal , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Animales , Ácido Aspártico Endopeptidasas/metabolismo , Células Cultivadas , Cognición/efectos de los fármacos , Diabetes Mellitus Experimental/psicología , Ghrelina/administración & dosificación , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipocampo/ultraestructura , Quinasa I-kappa B/metabolismo , Masculino , FN-kappa B/metabolismo , Neuronas/efectos de los fármacos , Neuronas/ultraestructura , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Estreptozocina/administración & dosificación , Sinapsis/efectos de los fármacos , Sinapsis/ultraestructura , Regulación hacia Arriba
13.
Rapid Commun Mass Spectrom ; 34(19): e8840, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32441059

RESUMEN

RATIONALE: Quantitatively relating 13 C/12 C, 2 H/1 H and 18 O/16 O ratios of plant α-cellulose and 2 H/1 H of n-alkanes to environmental conditions and metabolic status should ideally be based on the leaf, the plant organ most sensitive to environmental change. The fact that leaf organic matter is composed of isotopically different heterotrophic and autotrophic components means that it is imperative that one be able to disentangle the relative heterotrophic and autotrophic contributions to leaf organic matter. METHODS: We tackled this issue by two-dimensional sampling of leaf water and α-cellulose, and specific n-alkanes from greenhouse-grown immature and mature and field-grown mature banana leaves, taking advantage of their large areas and thick waxy layers. Leaf water, α-cellulose and n-alkane isotope ratios were then characterized using elemental analysis isotope ratio mass spectrometry (IRMS) or gas chromatography IRMS. A three-member (heterotrophy, autotrophy and photoheterotrophy) conceptual linear mixing model was then proposed for disentangling the relative contributions of the three trophic modes. RESULTS: We discovered distinct spatial leaf water, α-cellulose and n-alkane isotope ratio patterns that varied with leaf developmental stages. We inferred from the conceptual model that, averaged over the leaf blade, only 20% of α-cellulose in banana leaf is autotrophically laid down in both greenhouse-grown and field-grown banana leaves, while approximately 60% and 100% of n-alkanes are produced autotrophically in greenhouse-grown and field-grown banana leaves, respectively. There exist distinct lateral (edge to midrib) gradients in autotrophic contributions of α-cellulose and n-alkanes. CONCLUSIONS: Efforts to establish quantitative isotope-environment relationships should take into account the fact that the evaporative leaf water 18 O and 2 H enrichment signal recorded in autotrophically laid down α-cellulose is significantly diluted by the heterotrophically formed α-cellulose. The δ2 H value of field-grown mature banana leaf n-alkanes is much more sensitive than α-cellulose as a recorder of the growth environment. Quantitative isotope-environment relationship based on greenhouse-grown n-alkane δ2 H values may not be reliable.


Asunto(s)
Hojas de la Planta , Alcanos/análisis , Alcanos/química , Procesos Autotróficos , Celulosa/análisis , Celulosa/química , Celulosa/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Procesos Heterotróficos , Isótopos/análisis , Musa/química , Fotosíntesis/fisiología , Hojas de la Planta/química , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Agua/análisis , Agua/química , Ceras/análisis , Ceras/química , Ceras/metabolismo
14.
Rapid Commun Mass Spectrom ; 34(10): e8641, 2020 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31965648

RESUMEN

RATIONALE: Although the 2 H/1 H ratio of the carbon-bound hydrogens (C-Hs) in α-cellulose extracted from higher plants has long been used successfully for climate, environmental and metabolic studies, the assumption that bleaching with acidified NaClO2 to remove lignin before pure α-cellulose can be obtained does not alter the 2 H/1 H ratio of α-cellulose C-Hs has nonetheless not been tested. METHODS: For reliable application of the 2 H/1 H ratio of α-cellulose C-H, we processed plant materials representing different phytochemistries and photosynthetic carbon assimilation modes in isotopically contrasting bleaching media (with an isotopic difference of 273 mUr). All the isotope ratios were measured by elemental analyzer/isotope ratio mass spectrometry (EA/IRMS). RESULTS: Our results show that H from the bleaching medium does appear in the final pure α-cellulose product, although the isotopic alteration to the C-H in α-cellulose due to the incorporation of processing H from the medium is small if isotopically "natural" water is used to prepare the processing medium. However, under prolonged bleaching such an isotope effect can be significant, implying that standardizing the bleaching process is necessary for reliable 2 H/1 H measurement. CONCLUSIONS: The currently adopted method for removing lignin for α-cellulose extraction from higher plant materials with acidified NaClO2 bleaching is considered acceptable in terms of preserving the isotopic fidelity if isotopically "natural" water is used to prepare the bleaching solution.


Asunto(s)
Celulosa/química , Hidrógeno/análisis , Plantas/química , Carbono/análisis , Deuterio/análisis , Hidrólisis , Espectrometría de Masas/métodos , Agua/química
15.
Microb Pathog ; 128: 147-152, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30594639

RESUMEN

Tim-3 is highly expressed on monocytes and macrophages. Blocking Tim-3 was shown to promote macrophage activation. We previously showed that fecal bacteria from patients with active ulcerative colitis (UC) presented significantly higher capacity to stimulate monocyte activation, resulting in higher expression of MHC molecules, costimulatory molecules, and proinflammatory cytokines, but the underlying mechanism remained unclear. Here, we found that fecal bacteria could significantly downregulate the expression of Tim-3 on CD14+ classical monocytes in vitro. Compared to the monocytes from healthy individuals, the monocytes from UC patients not only presented lower Tim-3 expression directly ex vivo, but also presented lower Tim-3 expression after stimulation. Moreover, the extent of Tim-3 downregulation was higher in UC monocytes than in control monocytes. This effect was, at least in part, attributable to differences in fecal bacterium composition between UC patients and healthy controls, since when tested in unrelated volunteers, the fecal bacteria from UC patients presented higher capacity at mediating Tim-3 downregulation. Fecal bacteria also induced TNF-α and IL-6 secretion from monocytes, which was repressible by the Tim-3 ligand Galectin 9 (Gal-9). Interestingly, we found that monocytes from UC patients presented significantly reduced response to exogenous Gal-9, and the extent of Gal-9-mediated inhibition was directly correlated with the level of Tim-3 expression. Overall, our data suggested that the monocytes from UC patients presented lower Tim-3 expression and reduced response to exogenous Gal-9, and the fecal bacteria from UC patients could potently downregulate Tim-3 expression on monocytes in vitro.


Asunto(s)
Bacterias/patogenicidad , Colitis Ulcerosa/inmunología , Regulación hacia Abajo , Heces/microbiología , Receptor 2 Celular del Virus de la Hepatitis A/metabolismo , Monocitos/inmunología , Monocitos/metabolismo , Adulto , Colitis Ulcerosa/microbiología , Citocinas/metabolismo , Femenino , Galectinas/metabolismo , Expresión Génica , Receptor 2 Celular del Virus de la Hepatitis A/genética , Humanos , Interleucina-6/metabolismo , Receptores de Lipopolisacáridos/metabolismo , Masculino , Persona de Mediana Edad , Factor de Necrosis Tumoral alfa/metabolismo , Voluntarios
16.
Anal Chem ; 90(17): 10293-10301, 2018 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-30080403

RESUMEN

The 18O/16O ratio at both molecular and positional levels in the carbohydrates of higher plants is a reliable proxy for the plant growth environment, and a potential indicator of the plant photosynthetic carbon assimilation mode, and its physiological, biochemical and metabolic status. The lack of exploitable nuclear resonance in 18O and 16O and the extremely low 17O abundance make the NMR-based PSIA (position-specific isotopic analysis) a significant challenge. In this Article, an alternative three-step wet chemistry based method for accessing the 18O/16O of glucose O-3 is presented. The O atoms (OH groups) at positions 1, 2, 5, and 6 were first protected by acetonation (converting glucose to 1,2;5,6-di- O-isopropylidene-glucofuranose). The protected glucose was then esterified at O-3 by thionoformylation. Subsequent Barton-McCombie deoxygenation quantitatively removed the O-3 from the protected sugar. Mass balance was then applied to calculate the 18O/16O of O-3 using the isotopic values of the protected sugar before and after the deoxygenation step. The method is innovative in that (i) isolation and purification of individual compounds for 18O by EA/Pyrolysis/IRMS analysis is unnecessary as the reaction mixture can be analyzed on a GC/Pyrolysis/IRMS; (ii) sample quantity is dramatically reduced; and (iii) the approach to access the O-3 isotopic signal can be easily expanded to other positions within glucose and other sugars. It was shown that O-3 is enriched by 12 mUr relative to the molecular average (O-2-O-6) for a glucose of C4 photosynthetic origin. We highlighted the potential applications of the intramolecular O isotopic heterogeneity of glucose this method revealed.


Asunto(s)
Carbohidratos/química , Glucosa/química , Isótopos de Oxígeno/química , Plantas/química , Almidón/química , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Fotosíntesis
17.
Protein Expr Purif ; 142: 81-87, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28963005

RESUMEN

Lipases are among the most versatile biocatalysts, and are used in a range of industrially relevant bioconversion reactions. However, the production of LipA in recombinant Bacillus subtilis is still limited, due to unresolved issues surrounding the regulation of the expression and secretion systems. In this study, the gene encoding LipA from B. subtilis 168 was expressed in BNA under the control of the P43 and the PAE promoter. The extracellular lipase activity of the resulting strains BNACL and BNAAL was 7.8 U ml-1 and 12.6 U ml-1, respectively. To further enhance the expression of LipA, pHP13L was constructed by inserting the PAE-lip into the shuttle vector pHP13, which produced an extracellular lipase activity of 180.5 U ml-1 of BNA/pHP13L. The strain BNAY8 described in Supplement data which lacks eight extracellular proteins was constructed and the deletion a few of the much weaker secreting proteins had no significant effect on the secretion of LipA. Moreover, the four Sec pathway components, secA-prfB, secDF, secYEG, prsA, were individually overexpressed in BNA. The overexpression of secDF and prsA enhanced the production of LipA by 28% and 49%, respectively. Furthermore, the co-overexpression of secDF with prsA improved the extracellular amount of LipA by 59% over that of BNA/pHP13L, reaching 287.8 U ml-1. It can therefore be said that both regulatory elements and secretion pathway had an impact on the production of secreted LipA. Their optimization and modification is a useful strategy to improve the homologous overproduction of other extracellular proteins in B. subtilis.


Asunto(s)
Bacillus subtilis/enzimología , Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Vectores Genéticos/química , Lipasa/genética , Vías Secretoras , Bacillus subtilis/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Cartilla de ADN/síntesis química , Cartilla de ADN/metabolismo , Vectores Genéticos/metabolismo , Cinética , Lipasa/metabolismo , Regiones Promotoras Genéticas
18.
Bioorg Chem ; 81: 529-535, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30245234

RESUMEN

Halohydrin dehalogenases are remarkable enzymes which possess promiscuous catalytic activity and serve as potential biocatalysts for the synthesis of chiral halohydrins, epoxides and ß-substituted alcohols. The enzyme HheC exhibits a highly R enantioselectivity in the processes of dehalogenation of vicinal halohydrins and ring-opening of epoxides, which attracts more attentions in organic synthesis. Recently dozens of novel potential halohydrin dehalogenases have been identified by gene mining, however, most of the characterized enzymes showed low stereoselectivity. In this study, a novel halohydrin dehalogenase of HheA10 from Tsukamurella sp. 1534 has been heterologously expressed, purified and characterized. Substrate spectrum and kinetic resolution studies indicated the HheA10 was a highly S enantioselective enzyme toward several halohydrins, which produced the corresponding epoxides with the ee (enantiomeric excess) and E values up to >99% and >200 respectively. Our results revealed the HheA10 was a promising biocatalyst for the synthesis of enantiopure aromatic halohydrins and epoxides via enzymatic kinetic resolution of racemic halohydrins. What's more important, the HheA10 as the first individual halohydrin dehalogenase with the highly S enantioselectivity provides a complementary enantioselectivity to the HheC.


Asunto(s)
Actinomycetales/enzimología , Hidrolasas/metabolismo , Actinomycetales/genética , Actinomycetales/metabolismo , Clonación Molecular , Compuestos Epoxi/metabolismo , Hidrolasas/genética , Cinética , Estereoisomerismo , Especificidad por Sustrato , Temperatura
19.
J Med Internet Res ; 20(12): e12460, 2018 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-30559091

RESUMEN

BACKGROUND: Over 30 million people in the United States (over 9%) have been diagnosed with diabetes. About 25% of people with diabetes will experience a diabetic foot ulcer (DFU) in their lifetime. Unresolved DFUs may lead to sepsis and are the leading cause of lower-limb amputations. DFU rates can be reduced by screening patients with diabetes to enable risk-based interventions. Skin temperature assessment has been shown to reduce the risk of foot ulceration. While several tools have been developed to measure plantar temperatures, they only measure temperature once a day or are designed for clinic use only. In this report, wireless sensor-embedded socks designed for daily wear are introduced, which perform continuous temperature monitoring of the feet of persons with diabetes in the home environment. Combined with a mobile app, this wearable device informs the wearer about temperature increases in one foot relative to the other, to facilitate early detection of ulcers and timely intervention. OBJECTIVE: A pilot study was conducted to assess the accuracy of sensors used in daily wear socks, obtain user feedback on how comfortable sensor-embedded socks were for home use, and examine whether observed temperatures correlated with clinical observations. METHODS: Temperature accuracy of sensors was assessed both prior to incorporation in the socks, as well as in the completed design. The measured temperatures were compared to the reference standard, a high-precision thermostatic water bath in the range 20°C-40°C. A total of 35 patients, 18 years of age and older, with diabetic peripheral neuropathy were enrolled in a single-site study conducted under an Institutional Review Board-approved protocol. This study evaluated the usability of the sensor-embedded socks and correlated the observed temperatures with clinical findings. RESULTS: The temperatures measured by the stand-alone sensors were within 0.2°C of the reference standard. In the sensor-embedded socks, across multiple measurements for each of the six sensors, a high agreement (R2=1) between temperatures measured and the reference standard was observed. Patients reported that the socks were easy to use and comfortable, ranking them at a median score of 9 or 10 for comfort and ease of use on a 10-point scale. Case studies are presented showing that the temperature differences observed between the feet were consistent with clinical observations. CONCLUSIONS: We report the first use of wireless continuous temperature monitoring for daily wear and home use in patients with diabetes and neuropathy. The wearers found the socks to be no different from standard socks. The temperature studies conducted show that the sensors used in the socks are reliable and accurate at detecting temperature and the findings matched clinical observations. Continuous temperature monitoring is a promising approach as an early warning system for foot ulcers, Charcot foot, and reulceration.


Asunto(s)
Pie Diabético/terapia , Pie/irrigación sanguínea , Temperatura Cutánea , Adolescente , Adulto , Pie Diabético/patología , Femenino , Humanos , Masculino , Proyectos Piloto , Adulto Joven
20.
Tumour Biol ; 39(4): 1010428317697551, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28381163

RESUMEN

The protocadherin 7 is a member of the protocadherin family that expressed aberrantly in many types of human cancers. However, its expression, function, and underlying mechanisms are little known in gastric cancer. In this study, we detected protocadherin 7 expression in gastric cancer tissues and non-tumorous gastric mucosa tissues by real-time quantitative polymerase chain reaction and immunohistochemistry. The association of protocadherin 7 expression with the clinicopathological characteristics and the prognosis was subsequently analyzed. MTS ((3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium)) and transwell assays were performed to assess the effect of protocadherin 7 on proliferation, migration, and invasion in gastric cancer cell lines. Moreover, real-time quantitative polymerase chain reaction and western blot were used to detect the expression of epithelial-mesenchymal transition markers. Protocadherin 7 expression was decreased gradiently from normal tissue to gastric cancer, especially in gastric cancer tissue with lymph node metastasis. Low expression of protocadherin 7 was significantly associated with Lauren's classification ( p = 0.0005), lymph node metastases ( p = 0.0002), and tumor node metastasis stage ( p = 0.0221), as well as poor prognosis ( p < 0.05). Furthermore, down-regulation of protocadherin 7 in gastric cancer cell lines significantly increased their migration and invasion abilities (both p < 0.05), while it had no influence on the gastric cancer cell proliferation ( p > 0.05). Additionally, our results demonstrated that E-cadherin expression was down-regulated in gastric cancer cells with protocadherin 7 depletion. Our data indicated that protocadherin 7 may play important roles in the invasion and metastasis of gastric cancer, and protocadherin 7 could suppress cell migration and invasion through E-cadherin inhibition. Protocadherin 7 can serve as a novel biomarker for diagnostic and prognosis in patients with gastric cancer.


Asunto(s)
Cadherinas/fisiología , Movimiento Celular , Neoplasias Gástricas/patología , Adulto , Anciano , Antígenos CD , Línea Celular Tumoral , Proliferación Celular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Pronóstico , Protocadherinas
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