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1.
J Lipid Res ; : 100579, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38880128

RESUMEN

Sterol-regulatory element binding proteins (SREBPs) are a conserved transcription factor family governing lipid metabolism. When cellular cholesterol level is low, SREBP2 is transported from the endoplasmic reticulum to the Golgi apparatus where it undergoes proteolytic activation to generate a soluble N-terminal fragment, which drives the expression of lipid biosynthetic genes. Malfunctional SREBP activation is associated with various metabolic abnormalities. In this study, we find that overexpression of the active nuclear form SREBP2 (nSREBP2) causes caspase-dependent lytic cell death in various types of cells. These cells display typical pyroptotic and necrotic signatures, including plasma membrane ballooning and release of cellular contents. However, this phenotype is independent of the gasdermin family proteins or mixed lineage kinase domain-like (MLKL). Transcriptomic analysis identifies that nSREBP2 induces expression of p73, which further activates caspases. Through whole-genome CRISPR-Cas9 screening, we find that Pannexin-1 (PANX1) acts downstream of caspases to promote membrane rupture. Caspase-3 or 7 cleaves PANX1 at the C-terminal tail and increases permeability. Inhibition of pore-forming activity of PANX1 alleviates lytic cell death. PANX1 can mediate gasdermins and MLKL-independent cell lysis during TNF-induced or chemotherapeutic reagents (doxorubicin or cisplatin)-induced cell death. Together, this study uncovers a noncanonical function of SREBPs as a potentiator of programmed cell death and suggests that PANX1 can directly promote lytic cell death independent of gasdermins and MLKL.

2.
Opt Express ; 31(21): 34800-34816, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37859228

RESUMEN

Photonics-assisted millimeter-wave (MMW) wireless communications are advancing rapidly driven by the escalating congestion in the lower-band spectrum and the growing demand for higher data rates. Concurrently, Kramers-Kronig (KK) receivers provide an economical solution ideally suited for cost-sensitive deployment and application. However, the conventional KK receiver is subject to performance degradation due to the nonlinearity and memory effects introduced by practical electronic devices. In this work, the performance degradation of the conventional KK receiver is investigated and quantitatively simulated, showing that the KK receiver exhibits greater sensitivity to nonlinearity and memory effects compared to the conventional coherent receiver. To enhance the performance of KK receivers deployed in MMW communication systems, we propose a modified KK receiver employing memory polynomial compensation, namely MP-KK receiver, capable of effectively compensating memory effects whilst simultaneously addressing nonlinearity. Crucially, the memory polynomial model is employed prior to the KK algorithm to prevent further signal degradation caused by the nonlinear operator in the KK algorithm in the scenario of photonics-assisted MMW wireless communication based on the KK receiver. For verification, we present a 95 GHz W-band MMW wireless transmission demonstration with 20 Gb/s QPSK and 40 Gb/s 16-QAM signals. The experimental results indicate that the MP-KK receiver can achieve more than 3.5 dB improvement in EVM and 71.25% reduction in BER compared to the conventional approaches.

3.
J Chem Inf Model ; 63(24): 7669-7675, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38061777

RESUMEN

Generating new molecules with the desired physical or chemical properties is the key challenge of computational material design. Deep learning techniques are being actively applied in the field of data-driven material informatics and provide a promising way to accelerate the discovery of innovative materials. In this work, we utilize an invertible graph generative model to generate hypothetical promising high-temperature polymer dielectrics. A molecular graph generative model based on the invertible normalizing flow is trained on a data set containing 250k polymer molecular graphs (mostly generated by an RNN-based generative model) to learn the invertible transformations between latent distributions and molecular graph structures. When generating molecular graphs, a sample vector is drawn from the latent space, and then an adjacency tensor and node attribute matrix are generated through two invertible flows in two steps and assembled into a molecular graph. The model has the merits of exact likelihood training and an efficient one-shot generation process. The learned latent space is used to generate polymers with a high glass-transition temperature (Tg) and a wide band gap (Eg) for the application of high-temperature energy storage film capacitors. This work contributes to the efficient design of high-temperature polymer dielectrics by using deep generative models.


Asunto(s)
Polímeros , Temperatura , Modelos Moleculares , Probabilidad
4.
Mol Breed ; 43(10): 73, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37795156

RESUMEN

Tomato is a leading vegetable in modern agriculture, and with global warming, drought has become an important factor threatening tomato production. Mitogen-activated protein kinase 3 (MAPK3) plays an important role in plant disease and stress resistance. To clarify the downstream target proteins of SlMAPK3 and the mechanism of stress resistance in tomato, this study was conducted with the SlMAPK3-overexpressing lines OE-1 and OE-2 and the CRISPR/Cas9-mediated mutant lines slmapk3-1 and slmapk3-2 under PEG 6000-simulated drought. The results of yeast two-hybrid (Y2H), pull-down, and coimmunoprecipitation (Co-IP) assays confirmed that SlASR4 (NP_001269248.1) interacted with SlMAPK3. Analyses of the SlASR4 protein structure and SlASR4 expression under PEG 6000 and BTH stress revealed that SlASR4 has a highly conserved protein structural domain involved in the drought stress response under PEG 6000 treatment. The function of the SlASR4 and SlMAPK3 downstream target protein, in drought resistance in tomato plants, was identified by virus-induced gene silencing (VIGS). This study clarified that SlMAPK3 interacts with SlASR4 to positively regulate drought resistance in tomato plants.

5.
Clin Oral Investig ; 27(5): 1953-1964, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36637519

RESUMEN

OBJECTIVES: To assess the clinical efficacy of xenogeneic collagen matrix (XCM) plus apically positioned flap (APF) in augmenting the keratinized mucosa (KM) width (KMW) and thickness (KMT) around posterior mandibular implants and compare it with free gingival graft (FGG) plus APF. MATERIAL AND METHODS: Thirty patients with KMW ≤ 2 mm in the posterior mandibular implant site were randomly allocated to the FGG group (FGG plus APF) or the XCM group (XCM plus APF). Clinical assessments, including KMW and KMT, shrinkage rate of established KM, and peri-implant soft tissue health, were evaluated during a 6-month follow-up. Additionally, the esthetic outcomes and patient-reported postoperative morbidity were investigated. RESULTS: At 6 months, the KMW measured 3.60 ± 0.79 mm in the FGG group and 3.28 ± 0.96 mm in the XCM group (p = 0.186). Both groups showed a tendency for graft contraction (FGG, 42.11%; XCM, 53.22%). The KMT measured 1.24 ± 0.34 mm in the FGG group and 0.95 ± 0.29 mm in the XCM group, with statistical difference (p = 0.002). No difference in the peri-implant soft tissue health was observed between the two groups (p > 0.05), but the esthetic outcomes were better in the XCM group (p < 0.05). CONCLUSIONS: XCM plus APF rendered a similar clinical efficacy in augmenting KMW as that with FGG plus APF, but with higher shrinkage. XCM plus APF was inferior with respect to FGG plus APF in augmenting KMT. The esthetic outcomes were better with XCM plus APF than FGG plus APF. Clinical relevance XCM plus APF graft was inferior with respect to FGG plus APF in augmenting KMT. TRIAL REGISTRATION: Trial registration number: ChiCTR2200058027 and date: 03/27/2022.


Asunto(s)
Implantes Dentales , Gingivoplastia , Humanos , Gingivoplastia/métodos , Tejido Conectivo/trasplante , Estética Dental , Colágeno/uso terapéutico , Membrana Mucosa , Encía/trasplante
6.
BMC Cancer ; 22(1): 505, 2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35524225

RESUMEN

BACKGROUND: We aim to investigate the prognostic value of weight loss during radiotherapy (RT) among patients with nasopharyngeal carcinoma (NPC). METHODS: A total of 1149 NPC patients who received radical RT were retrospectively analyzed. Patients' weight were measured at initiation of RT (WPre-RT) and every week during RT (WRT1,2,3,4,5,6,7). Percentage of weight loss (PWL) at 1st, 2nd, 3rd, 4th, 5th, 6th, and 7th week of RT (RT-PWL1,2,3,4,5,6,7) were calculated using the following equation: (WPre-RT -WRT1,2,3,4,5,6,7)/WPre-RT × 100%. The optimal threshold of RT-PWL7 was determined by recursive partitioning analyses (RPAs). Our endpoints included disease-free survival (DFS), overall survival (OS), distant metastasis-free survival (DMFS), and locoregional relapse-free survival (LRRFS). RESULTS: The median RT-PWLs were 0, 0, 1.5, 2.9, 4.1, 5.5, 6.6% at 1st, 2nd, 3rd, 4th, 5th, 6th, and 7th week of RT, respectively. RT-PWL7 optimal threshold with respect to DFS was 5.3% based on RPAs. Therefore, a consistent threshold of 5% (<5% vs > ≥5%) was selected to classify NPC patients into low RT-PWL7 and high RT-PWL7 groups for survival analysis. Compared to high RT-PWL7 (≥5%), patients with low RT-PWL7 (< 5%) had significantly better ten-year DFS (61.2% vs 78.8%; P < 0.001), OS (70.1% vs 86.6%; P < 0.001), and DMFS (80.2% vs 88.5%; P = 0.007). However, no difference was observed between LRRFS groups (91.7% vs 94.3%; P = 0.173). In multivariate analysis, high RT-PWL7 was an independent risk factor for DFS (HR, 1.56; 95%CI, 1.19-2.03; P = 0.001), OS (HR, 1.54; 95%CI, 1.11-2.15; P = 0.011), and DMFS (HR, 1.47; 95%CI, 1.03-2.10; P = 0.033) in patients with NPC. In addition, treatment strategy, plasma Epstein-Barr virus DNA, and N stage were associated with weight loss. CONCLUSIONS: High RT-PWL7 was significantly associated with decreased DFS, OS, and DMFS for NPC patients. Clinicians should continuously inform patients on the health impact of minimizing RT-PWL7 under 5% during radiotherapy.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Estudios de Cohortes , Supervivencia sin Enfermedad , Herpesvirus Humano 4/genética , Humanos , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/patología , Recurrencia Local de Neoplasia/complicaciones , Pronóstico , Radioterapia de Intensidad Modulada/métodos , Estudios Retrospectivos , Pérdida de Peso
7.
Inorg Chem ; 61(10): 4246-4250, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-35230834

RESUMEN

A new acentric barium borate, Ba2B10O16(OH)2·(H3BO3)(H2O) (1), was synthesized via a hydrothermal process. Compound 1 contains two different boron oxide units of [B5O10(OH)]6- anions and H3BO3 molecules and features 9-ring channels along the c axis in a layered structure. This barium borate is a possible deep-ultraviolet nonlinear-optical crystal for its moderate second-harmonic-generation signal and wide transparency window below 190 nm.

8.
Antonie Van Leeuwenhoek ; 115(4): 473-486, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35119545

RESUMEN

Two yellow-pigmented bacterial strains, LZ-14 T and ABI-LZ29, were isolated from the cultivable phycosphere microbiota of the highly toxic marine dinoflagellate Alexandrium catenella LZT09 and demonstrated obvious microalgae growth-promoting potentials toward the algal host. To elucidate the taxonomic status of the two bioactive bacterial strains, they were subjected to a polyphasic taxonomic characterization. Both strains were found to be Gram-negative, aerobic, rod-shaped and motile; to contain Q-10 as the predominant ubiquinone; summed feature 8, C16:0, C18:1 ω7c 11-methyl and summed feature 3 as the major fatty acids; and diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and two unidentified phospholipids as the predominant polar lipids. Based on the phylogenetic analysis, phylogenomic inferences and phenotypic characteristics, the strains could be clearly distinguished from phylogenetically closely related species and formed a distinct monophyletic lineage in the family Rhodobacteraceae. The size of the draft genome of strain LZ-14 T is 4.615 Mb, with a DNA G + C content of 63.3 mol%. It contains ten predicted secondary metabolite biosynthetic gene clusters and core genes for bacterial exopolysaccharide biosynthesis. Therefore, strain LZ-14 T (= CCTCC AB 2017230 T = KCTC 62342 T) represents a novel species of a new genus, for which the name Alexandriicola marinus gen. nov., sp. nov., is proposed.


Asunto(s)
Rhodobacteraceae , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Ácidos Grasos/análisis , Fosfolípidos/análisis , Filogenia , ARN Ribosómico 16S/genética , Rhodobacteraceae/genética , Análisis de Secuencia de ADN
9.
Mar Drugs ; 20(5)2022 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-35621971

RESUMEN

Microalgae host varied microbial consortium harboring cross-kingdom interactions with fundamental ecological significance in aquatic ecosystems. Revealing the complex biofunctions of the cultivable bacteria of phycosphere microbiota is one vital basis for deeply understanding the mechanisms governing these dynamic associations. In this study, a new light-yellow pigmented bacterial strain LZ-28 was isolated from the highly-toxic and harmful algal bloom-forming dinoflagellate Alexandrium catenella LZT09. Collective phenotypic and genotypic profiles were obtained to confidently identify this strain as a new Mameliellaalba member. Comparative genomic analysis showed that strain LZ-28 shared highly similar functional features with other four marine algae-derived M. alba strains in spite of their distinctive isolation sources. Based on the bioactivity assaying, the mutual growth-promoting effects between bacterial strain LZ-28 and algal strain LZT09 were observed. After the culture conditions were optimized, strain LZ-28 demonstrated an extraordinary production ability for its bioflocculanting exopolysaccharides (EPS). Moreover, the portions of two monosaccharides glucose and fucose of the EPS were found to positively contribute to the bioflocculanting capacity. Therefore, the present study sheds light on the similar genomic features among the selected M. alba strains, and it also reveals the potential pharmaceutical, environmental and biotechnological implications of active EPS produced by this new Mameliella alba strain LZ-28 recovered from toxic bloom-forming marine dinoflagellate.


Asunto(s)
Dinoflagelados , Microbiota , Rhodobacteraceae , Dinoflagelados/genética , Floraciones de Algas Nocivas
10.
J Integr Neurosci ; 21(2): 46, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35364634

RESUMEN

Alzheimer's disease (AD) is a neurodegeneration csharacterized by amyloid-ß (Aß) deposition and abnormally phosphorylated Tau protein aggregation. Autophagy, as an important cellular metabolic activity, is closely related to the production, secretion and clearance of Aß peptide and Tau phosphorylation level. Therefore, autophagy may become a potential target for AD treatment. A large number of molecules are involved in the mammalian target of rapamycin (mTOR)-dependent or mTOR-independent pathway of autophagy. More and more evidences show that statins can intervene autophagy by regulating the activity or expression level of autophagy-related proteins and genes. On the one hand, statins can induce autophagy through Sirtuin1 (SIRT1), P21, nuclear P53 and adenylate activated protein kinase (AMPK). On the other hand, statins inhibit the mevalonate metabolism pathway, thereby interfering with the prenylation of small GTPases, leading to autophagy dysfunction. Statins can also reduce the levels of LAMP2 and dynein, destroying autophagy. In this review, we focused on the role of autophagy in AD and the autophagy mechanism of statins in the potential treatment of AD.


Asunto(s)
Enfermedad de Alzheimer , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Autofagia , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Transducción de Señal
11.
Zhongguo Zhong Yao Za Zhi ; 47(13): 3432-3438, 2022 Jul.
Artículo en Zh | MEDLINE | ID: mdl-35850793

RESUMEN

The prevalence of chronic kidney disease(CKD) increases year by year and has become a highly prevalent disease, seriously affecting the quality of life of patients and bringing heavy family burden. There are many diseases causing CKD, including va-rious primary and secondary glomerulonephritis, renal tubular injury, and renal vascular lesions. Although routine medical treatment for CKD can alleviate the clinical symptoms to a certain extent, it is sometimes difficult to prevent the progression of CKD. Traditional Chinese medicine(TCM) is advantageous in high safety, few adverse reactions, and definite clinical efficacy in the treatment of CKD. The active components contained can play a synergistic effect through multiple pathways and multiple targets to delay disease progression, but its mechanism of action has not been fully elucidated. As revealed by the literature in this field in China and abroad, abnormal mitophagy is a common feature of the pathogenesis of CKD of different types. In recent years, a large number of studies have proved that the regulation of mitophagy through the PINK1/Parkin signaling pathway and mitophagy receptor pathway could delay the progression of CKD and protect renal function. Therefore, the regulation of mitophagy by TCM in the prevention and treatment of CKD through related pathways has become a potential therapeutic target in recent years. This paper reviewed the research articles on the definite efficacy of TCM in preventing and treating CKD by regulating mitophagy through relevant pathways to provide new targets and stra-tegies for preventing and treating CKD and delaying their entry into end-stage renal diseases.


Asunto(s)
Mitofagia , Insuficiencia Renal Crónica , Humanos , Riñón/patología , Medicina Tradicional China , Mitofagia/fisiología , Calidad de Vida , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/prevención & control
12.
Antonie Van Leeuwenhoek ; 114(12): 2003-2017, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34532778

RESUMEN

A novel actinobacterium NJES-13T was isolated from the gut of Antarctic emperor penguin Aptenodytes forsteri. The new isolate produces bioactive gephyromycin metabolites and exopolysaccharides (EPS). Cells were Gram-negative, motile with the peritrichous flagella, and with a faint layer of extracellular slime. Colonies were yellow when grown on marine agar, ISP1, 2, 4 and TSA media. The strain developed clusters of coccoid, and divided by binary fission in the early phase of growth. The cell clusters were gradually disrupted during the stationary phase and formed short rod-shape cells which were interconnected by viscous EPS showing a three-dimensional net-like morphology, and contained polyhydroxyalkanoates (PHA) granules inside the cells. Growth of strain NJES-13T was observed at 15-45 °C, at pH 6.0-9.0 with 0.5-9.0% (w/v) NaCl. The complete genomic size of strain NJES-13T was 3.45 Mb with a DNA G + C content of 67.0 mol%. The combined polyphasic taxonomic characterizations presented in this study unequivocally separated strain NJES-13T from all known genera in the family Dermatophilaceae. Thus, strain NJES-13T represents a novel species of a new genus, for which the name Gephyromycinifex aptenodytis gen. nov., and sp. nov. is proposed. The type strain is NJES-13T (= CCTCC 2019007T = KCTC 49281T). Genetic prediction of secondary metabolite biosynthesis revealed a 44.5 kb-long biosynthetic gene cluster (BGC) of type III polyketide synthase (PKS) as well as four other BGCs, indicating its great potential to produce novel bioactive metabolites derived from the gut microbiota of animals living in the extreme habitats in the Antarctica.


Asunto(s)
Spheniscidae , Animales , Regiones Antárticas , Técnicas de Tipificación Bacteriana , ADN Bacteriano , Ácidos Grasos/análisis , Fosfolípidos/análisis , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN
13.
Mar Drugs ; 20(1)2021 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-35049888

RESUMEN

Strain NJES-13T is the type strain and currently the only species of the newly established actinobacteria genera Aptenodytes in the family Dermatophilaceae isolated from the gut microbiota of the Antarctic emperor penguin. This strain demonstrated excellent bioflocculation activity with bacteria-derived exopolysaccharides (EPSs). Moreover, it produced bioactive angucycline/angucyclinone derivatives (ADs) and contained one type III polyketide synthase (T3PKS), thus demonstrating great potential to produce novel bioactive compounds. However, the low productivity of the potential new AD metabolite was the main obstacle for its chemical structure elucidation. In this study, to increase the concentration of targeted metabolites, the influence of cellular morphology on AD metabolism in strain NJES-13T was determined using glass bead-enhanced fermentation. Based on the cellular ultra-structural observation driven by bacterial EPSs, and quantitative analysis of the targeted metabolites, the successful increasing of the productivity of three AD metabolites was achieved. Afterward, a new frigocyclinone analogue was isolated and then identified as 2-hydroxy-frigocyclinone, as well as two other known ADs named 2-hydroxy-tetrangomycin (2-HT) and gephyromycin (GPM). Three AD metabolites were found to demonstrate different bioactivities. Both C-2 hydroxyl substitutes, 2-hydroxy-tetrangomycin and 2-hydroxy-frigocyclinone, exhibited variable inhibitory activities against Staphylococcus aureus, Bacillus subtilis and Candida albicans. Moreover, the newly identified 2-hydroxy-frigocyclinone also showed significant cytotoxicity against three tested human-derived cancerous cell lines (HL-60, Bel-7402 and A549), with all obtained IC50 values less than 10 µM. Based on the genetic analysis after genomic mining, the plausible biogenetic pathway of the three bioactive ADs in strain NJES-13T was also proposed.


Asunto(s)
Actinobacteria , Antraquinonas/farmacología , Antibacterianos/farmacología , Antineoplásicos/farmacología , Spheniscidae , Animales , Antraquinonas/química , Antibacterianos/química , Antineoplásicos/química , Organismos Acuáticos , Bacillus subtilis/efectos de los fármacos , Candida albicans/efectos de los fármacos , Línea Celular Tumoral/efectos de los fármacos , Humanos , Staphylococcus aureus/efectos de los fármacos
14.
Chembiochem ; 21(18): 2680-2688, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32324965

RESUMEN

Glucose dehydrogenase (GDH) is a general tool for driving nicotinamide (NAD(P)H) regeneration in synthetic biochemistry. An increasing number of synthetic bioreactions are carried out in media containing high amounts of organic cosolvents or hydrophobic substrates/products, which often denature native enzymes, including those for cofactor regeneration. In this work, we attempted to improve the chemical stability of Bacillus megaterium GDH (BmGDHM0 ) in the presence of large amounts of 1-phenylethanol by directed evolution. Among the resulting mutants, BmGDHM6 (Q252L/E170K/S100P/K166R/V72I/K137R) exhibited a 9.2-fold increase in tolerance against 10 % (v/v) 1-phenylethanol. Moreover, BmGDHM6 was also more stable than BmGDHM0 when exposed to hydrophobic and enzyme-inactivating compounds such as acetophenone, ethyl 2-oxo-4-phenylbutyrate, and ethyl (R)-2-hydroxy-4-phenylbutyrate. Coupled with a Candida glabrata carbonyl reductase, BmGDHM6 was successfully used for the asymmetric reduction of deactivating ethyl 2-oxo-4-phenylbutyrate with total turnover number of 1800 for the nicotinamide cofactor, thus making it attractive for commercial application. Overall, the evolution of chemically robust GDH facilitates its wider use as a general tool for NAD(P)H regeneration in biocatalysis.


Asunto(s)
Glucosa 1-Deshidrogenasa/metabolismo , Niacinamida/metabolismo , Bacillus megaterium/enzimología , Alcoholes Bencílicos/química , Alcoholes Bencílicos/metabolismo , Glucosa 1-Deshidrogenasa/química , Glucosa 1-Deshidrogenasa/genética , Estructura Molecular , Mutación , Niacinamida/química , Oxidación-Reducción , Fenilbutiratos/química , Fenilbutiratos/metabolismo
15.
BMC Med Genet ; 21(1): 181, 2020 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-32919460

RESUMEN

BACKGROUND: The complement component (3b/4b) receptor 1 gene (CR1) gene has been proved to affect the susceptibility of Alzheimer's disease (AD) in different ethnic and districts groups. However, the effect of CR1 genetic variants on amyloid ß (Aß) metabolism of AD human is still unclear. Hence, the aim of this study was to investigate genetic influences of CR1 gene on Aß metabolism. METHODS: All data of AD patients and normal controls (NC) were obtained from alzheimer's disease neuroimaging initiative database (ADNI) database. In order to assess the effect of each single nucleotide polymorphism (SNP) of CR1 on Aß metabolism, the PLINK software was used to conduct the quality control procedures to enroll appropriate SNPs. Moreover, the correlation between CR1 genotypes and Aß metabolism in all participants were estimated with multiple linear regression models. RESULTS: After quality control procedures, a total of 329 samples and 83 SNPs were enrolled in our study. Moreover, our results identified five SNPs (rs10494884, rs11118322, rs1323721, rs17259045 and rs41308433), which were linked to Aß accumulation in brain. In further analyses, rs17259045 was found to decrease Aß accumulation among AD patients. Additionally, our study revealed the genetic variants in rs12567945 could increase CSF Aß42 in NC population. CONCLUSIONS: Our study had revealed several novel SNPs in CR1 genes which might be involved in the progression of AD via regulating Aß accumulation. These findings will provide a new basis for the diagnosis and treatment AD.


Asunto(s)
Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Neuroimagen/métodos , Fragmentos de Péptidos/líquido cefalorraquídeo , Polimorfismo de Nucleótido Simple , Receptores de Complemento 3b/genética , Anciano , Anciano de 80 o más Años , Alelos , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Biomarcadores/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Femenino , Genotipo , Humanos , Masculino , Fragmentos de Péptidos/metabolismo
16.
Bioorg Chem ; 95: 103489, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31862456

RESUMEN

Five new isoquinolines (1-5) were isolated from national herb Corydalis tomentella. Their structures were elucidated by extensive analysis of the 1D and 2D NMR spectra and from the HRESIMS. Absolute configurations of 1-3 were determined by comparing their experimental and computed ECD data. Since plants from Corydalis have been reported to protect against Alzheimer's disease, all compounds were evaluated for their neuroprotective effect against lipopolysaccharide-induced BV2 microglia cells. Compound 2 and 3 showed well anti-neuroinflammatory activity at low concentration (25 µM).


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Corydalis/química , Isoquinolinas/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Microglía/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Teoría Funcional de la Densidad , Relación Dosis-Respuesta a Droga , Isoquinolinas/química , Isoquinolinas/aislamiento & purificación , Lipopolisacáridos/farmacología , Ratones , Estructura Molecular , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Relación Estructura-Actividad
17.
Opt Express ; 27(22): 31913-31925, 2019 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-31684414

RESUMEN

High power continuous-wave (CW) single-frequency 1342 nm lasers are of interest for fundamental research, particularly, for laser cooling of lithium atoms. Using the popular Nd:YVO4 laser crystal requires careful heat management, because strong thermal effects in the gain medium are the most severe limitations of output power. Here, we present a multi-segmented Nd:YVO4 crystal design that consists of three segments with successive doping concentrations, optimized using a theoretical model. In order to quantify the optimization, we measured the thermal lens power of conventional crystal designs and compare them to our multi-segmented design. The optimized design displays a two times lower thermal lens dioptric power for the same amount of absorbed pump power in the non-lasing case. Using the optimized design, we demonstrate a high power all-solid-state laser emitting 10.0 W single-frequency radiation at 1342 nm when operating the laser crystal at room temperature. Further integration of the laser allows us to operate the laser crystal below room temperature for improving output power up to 11.4 W at 8°C. This is explained by the reduction of energy-transfer upconversion and excited-state absorption effects. Stable free-running operation at the low temperature of 8 °C is achieved with the power stability of ± 0.42 % by peak-to-peak fluctuation and frequency peak-to-peak fluctuation of ± 72 MHz in three hours.

18.
J Natl Compr Canc Netw ; 17(10): 1174-1183, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31590148

RESUMEN

BACKGROUND: Differences between the features of primary cancer and matched metastatic cancer have recently drawn attention in research. This study investigated the concordance in microsatellite instability (MSI) and mismatch repair (MMR) status between primary and corresponding metastatic colorectal cancer (CRC). METHODS: Consecutive patients with metastatic CRC who had both primary and metastatic tumors diagnosed at our institution in January 2008 through December 2016 were identified. Immunohistochemistry was used to test the MMR status of both primary and matched metastatic tumors, and PCR analysis was performed to test MSI in patients with deficient MMR (dMMR) status. RESULTS: A total of 369 patients were included. Of the 46 patients with MSI-high primary tumors, 37 (80.4%) also had MSI-high metastatic tumors, whereas 9 (19.6%) had microsatellite stable (MSS) metastatic tumors. A high concordance was found in patients with liver, lung, or distant lymph node metastases. Interestingly, the discrepancy was more likely to be limited to peritoneal (5/20) or ovarian (4/4) metastasis (chi-square test, P<.001). These organ-specific features were also found in the pooled analysis. Along with the change of MSI-high in primary cancer to MSS in metastatic cancer, lymphocyte infiltration decreased significantly (P=.008). However, the change did not influence survival; the median overall survival of MSI-high and MSS metastatic tumors was 21.3 and 21.6 months, respectively (P=.774). The discrepancy rate was 1.6% for patients with proficient MMR primary tumors. CONCLUSIONS: For patients with dMMR primary tumors, the concordance of MSI and MMR status in primary CRC and corresponding metastatic cancer is potentially organ-specific. High concordance is found in liver, lung, and distant lymph node metastases, whereas discrepancy is more likely to occur in peritoneal or ovarian metastasis. Rebiopsy to evaluate MSI-high/dMMR status might be needed during the course of anti-PD-1 therapy in cases of peritoneal or ovarian metastasis.


Asunto(s)
Neoplasias Colorrectales/genética , Reparación de la Incompatibilidad de ADN/genética , Adulto , Anciano , Neoplasias Colorrectales/patología , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia
19.
J Transl Med ; 16(1): 273, 2018 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-30286769

RESUMEN

BACKGROUND: Systemic inflammation and immune dysfunction has been proved to be significantly associated with cancer progression and metastasis in many cancer types, including colorectal cancer. We examined the prognostic significance of the systemic immune-inflammation index (SII) in patients with metastatic colorectal cancer (mCRC) and the relationship between the lymphocytic response to the tumor and this index. METHODS: This retrospective study evaluated 240 consecutive patients with newly diagnosed stage IV mCRC who underwent surgical resection. The SII values were calculated based on preoperative laboratory data regarding platelet, neutrophil, and lymphocyte counts. Tumor-infiltrating lymphocytes were evaluated using the surgical specimens. The overall survival and their 95% confidence interval (95% CI) were estimated by regression analyses and the Kaplan-Meier method. RESULTS: After a mean follow-up of 26.7 (1.1-92.4) months, 146 patients (60.8%) died. In the univariate analysis, a high SII was significantly associated with poor overall survival (P = 0.009). The multivariable analysis also confirmed that a high SII was independently associated with poor overall survival (hazard ratio: 1.462, 95% confidence interval 1.049-2.038, P = 0.025). The SII value was significantly correlated with the TILs value at the tumor's center (P = 0.04), but not at the invasive margin (P = 0.39). When we evaluated overall survival for groupings of the tumor-infiltrating lymphocytes and SII values, we identified three distinct prognostic groups. The group with low tumor-infiltrating lymphocyte values and high SII values had the worst prognosis. CONCLUSIONS: A high SII value independently predicts poor clinical outcomes among patients with mCRC. In addition, combining the lymphocytic response to the tumor and SII could further enhance prognostication for mCRC.


Asunto(s)
Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Inflamación/inmunología , Estimación de Kaplan-Meier , Linfocitos/inmunología , Anciano , Femenino , Humanos , Inflamación/patología , Masculino , Persona de Mediana Edad , Pronóstico , Microambiente Tumoral
20.
J Transl Med ; 16(1): 195, 2018 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-30005666

RESUMEN

BACKGROUND: Currently, mismatch repair-deficient (dMMR) status is a promising candidate for targeted immune checkpoint inhibition therapy in colorectal cancer (CRC) patients, however, the potential immunological mechanism has not yet been well clarified and some other predictors need to be excavated as well. METHODS: We collected 330 CRC patients by the match of mismatch repair-proficient (167) and dMMR (163), explored the relationship between MMR status and some important immune molecules including MHC class I, CD3, CD4, CD8, CD56, programmed death-1 and programmed death ligand-1, and investigated the risk factors for dMMR status as well as low MHC class I expression. The Pearson Chi square test was used for analyzing the associations between clinicopathological and immune characteristics and MMR status, and two categories logistic regression model was used for univariate and multivariate analysis to predict the odds ratio of risk factors for dMMR status and low MHC class I expression. RESULTS: Multivariate logistic regression analysis showed that low MHC class I and CD4 expression and high CD8 expression were significant risk factors for dMMR status [odds ratio (OR) = 24.66, 2.94 and 2.97, respectively; all p < 0.05] and dMMR status was the only risk factor for low MHC class I expression (OR = 15.34; p < 0.001). CONCLUSIONS: High CD8 and low MHC class I expression suggests the contradiction and complexity of immune microenvironment in dMMR CRC patients. Some other immunocytes such as CD56+ cells might also participate in the process of immune checkpoint inhibition, whereas needs further investigations.


Asunto(s)
Neoplasias Colorrectales/inmunología , Reparación de la Incompatibilidad de ADN/inmunología , Neoplasias Colorrectales/patología , Femenino , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Riesgo
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