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1.
Nat Cell Biol ; 25(12): 1774-1786, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37957325

RESUMEN

The intricate orchestration of enzymatic activities involving nicotinamide adenine dinucleotide (NAD+) is essential for maintaining metabolic homeostasis and preserving genomic integrity. As a co-enzyme, NAD+ plays a key role in regulating metabolic pathways, such as glycolysis and Kreb's cycle. ADP-ribosyltransferases (PARPs) and sirtuins rely on NAD+ to mediate post-translational modifications of target proteins. The activation of PARP1 in response to DNA breaks leads to rapid depletion of cellular NAD+ compromising cell viability. Therefore, the levels of NAD+ must be tightly regulated. Here we show that exogenous NAD+, but not its precursors, has a direct effect on mitochondrial activity. Short-term incubation with NAD+ boosts Kreb's cycle and the electron transport chain and enhances pyrimidine biosynthesis. Extended incubation with NAD+ results in depletion of pyrimidines, accumulation of purines, activation of the replication stress response and cell cycle arrest. Moreover, a combination of NAD+ and 5-fluorouridine selectively kills cancer cells that rely on de novo pyrimidine synthesis. We propose an integrated model of how NAD+ regulates nucleotide metabolism, with relevance to healthspan, ageing and cancer therapy.


Asunto(s)
Glucólisis , NAD , NAD/metabolismo , Redes y Vías Metabólicas , Genómica , Replicación del ADN
2.
Cell Rep ; 42(1): 111979, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36640322

RESUMEN

The role of MDC1 in the DNA damage response has been extensively studied; however, its impact on other cellular processes is not well understood. Here, we describe the role of MDC1 in transcription as a regulator of RNA polymerase II (RNAPII). Depletion of MDC1 causes a genome-wide reduction in the abundance of actively engaged RNAPII elongation complexes throughout the gene body of protein-encoding genes under unperturbed conditions. Decreased engaged RNAPII subsequently alters the assembly of the spliceosome complex on chromatin, leading to changes in pre-mRNA splicing. Mechanistically, the S/TQ domain of MDC1 modulates RNAPII-mediated transcription. Upon genotoxic stress, MDC1 promotes the abundance of engaged RNAPII complexes at DNA breaks, thereby stimulating nascent transcription at the damaged sites. Of clinical relevance, cancer cells lacking MDC1 display hypersensitivity to RNAPII inhibitors. Overall, we unveil a role of MDC1 in RNAPII-mediated transcription with potential implications for cancer treatment.


Asunto(s)
ARN Polimerasa II , Empalme del ARN , Daño del ADN , ARN Polimerasa II/metabolismo , Transcripción Genética , Humanos
3.
Cell Death Differ ; 29(8): 1639-1653, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35194187

RESUMEN

Viral infections enhance cancer risk and threaten host genome integrity. Although human cytomegalovirus (HCMV) proteins have been detected in a wide spectrum of human malignancies and HCMV infections have been implicated in tumorigenesis, the underlying mechanisms remain poorly understood. Here, we employed a range of experimental approaches, including single-molecule DNA fiber analysis, and showed that infection by any of the four commonly used HCMV strains: AD169, Towne, TB40E or VR1814 induced replication stress (RS), as documented by host-cell replication fork asymmetry and formation of 53BP1 foci. The HCMV-evoked RS triggered an ensuing host DNA damage response (DDR) and chromosomal instability in both permissive and non-permissive human cells, the latter being particularly relevant in the context of tumorigenesis, as such cells can survive and proliferate after HCMV infection. The viral major immediate early enhancer and promoter (MIEP) that controls expression of the viral genes IE72 (IE-1) and IE86 (IE-2), contains transcription-factor binding sites shared by promoters of cellular stress-response genes. We found that DNA damaging insults, including those relevant for cancer therapy, enhanced IE72/86 expression. Thus, MIEP has been evolutionary shaped to exploit host DDR. Ectopically expressed IE72 and IE86 also induced RS and increased genomic instability. Of clinical relevance, we show that undergoing standard-of-care genotoxic radio-chemotherapy in patients with HCMV-positive glioblastomas correlated with elevated HCMV protein markers after tumor recurrence. Collectively, these results are consistent with our proposed concept of HCMV hijacking transcription-factor binding sites shared with host stress-response genes. We present a model to explain the potential oncomodulatory effects of HCMV infections through enhanced replication stress, subverted DNA damage response and induced genomic instability.


Asunto(s)
Citomegalovirus , Daño del ADN , Carcinogénesis/genética , Citomegalovirus/genética , Citomegalovirus/metabolismo , Inestabilidad Genómica , Humanos , Regiones Promotoras Genéticas , Replicación Viral
4.
J Clin Hypertens (Greenwich) ; 23(7): 1452-1456, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34080288

RESUMEN

People with HIV (PWH) have a >2-fold greater risk for development of cardiovascular disease (CVD), which may be associated with abnormalities in 24-h ambulatory blood pressure measurement (ABPM) profile. We conducted a nested case-control study of ABPM in 137 PWH and HIV-uninfected controls with normal and high clinic blood pressure (BP) in Tanzania. Nocturnal non-dipping of heart rate (HR) was significantly more common among PWH than HIV-uninfected controls (p = .01). Nocturnal non-dipping of BP was significantly more common in PWH with normal clinic BP (p = .048). Clinical correlates of nocturnal non-dipping were similar in PWH and HIV-uninfected adults and included higher BMI, higher CD4+ cell count, and high C-reactive protein for HR and markers of renal disease for BP. In conclusion, nocturnal non-dipping of both BP and HR was more common in PWH but further research is needed to determine causes and consequences of this difference.


Asunto(s)
Infecciones por VIH , Hipertensión , Adulto , Presión Sanguínea , Monitoreo Ambulatorio de la Presión Arterial , Estudios de Casos y Controles , Ritmo Circadiano , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Frecuencia Cardíaca , Humanos , Hipertensión/epidemiología , Tanzanía/epidemiología
5.
J Neurosci ; 40(47): 9148-9162, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-33087471

RESUMEN

A single stressful event can cause morphologic and functional changes in neurons and even malfunction of vascular systems, which can lead to acute stress disorder or post-traumatic stress disorder. However, there is a lack of evidence regarding how acute stress impacts neuronal activity, the concurrent vascular response, and the relationship between these two factors, which is defined as neurovascular coupling. Here, using in vivo two-photon imaging, we found that NMDA-evoked calcium transients of excitatory neurons were impaired and that vasodilation of penetrating arterioles was concomitantly disrupted in acutely stressed male mice. Furthermore, acute stress altered the relationship between excitatory neuronal calcium coherence and vascular responses. By measuring NMDA-evoked excitatory and inhibitory neuronal calcium activity in acute brain slices, we confirmed that neuronal coherence both between excitatory neurons and between excitatory and inhibitory neurons was reduced by acute stress but restored by blockade of glucocorticoid receptor signaling. Furthermore, the ratio of sEPSCs to sIPSCs was altered by acute stress, suggesting that the excitation-inhibition balance was disrupted by acute stress. In summary, in vivo, ex vivo, and whole-cell recording studies demonstrate that acute stress modifies excitatory-inhibitory neuronal coherence, disrupts the excitation-inhibition balance, and causes consequent neurovascular coupling changes, providing critical insights into the neural mechanism of stress-induced disorders.SIGNIFICANCE STATEMENT Acute stress can cause pathologic conditions, such as acute stress disorder and post-traumatic stress disorder, by affecting the functions of neurons and blood vessels. However, investigations into the impacts of acute stress on neurovascular coupling, the tight connection between local neural activity and subsequent blood flow changes, are lacking. Through investigations at the in vivo, ex vivo, and whole-cell recording levels, we found that acute stress alters the NMDA-evoked vascular response, impairs the function and coherence of excitatory and inhibitory neurons, and disrupts the excitatory and inhibitory balance. These novel findings provide insights into the relevance of the excitatory-inhibitory balance, neuronal coherence, and neurovascular coupling to stress-induced disorders.


Asunto(s)
Neuronas/patología , Acoplamiento Neurovascular/fisiología , Estrés Psicológico/patología , Enfermedad Aguda , Animales , Señalización del Calcio , Circulación Cerebrovascular/fisiología , Corticosterona/fisiología , Técnicas In Vitro , Masculino , Ratones , Ratones Endogámicos C57BL , N-Metilaspartato/farmacología , Inhibición Neural , Técnicas de Placa-Clamp , Receptores de Glucocorticoides/fisiología , Restricción Física
6.
Am J Hypertens ; 33(12): 1087-1091, 2020 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-32776154

RESUMEN

BACKGROUND: Hypertensive urgency is associated with a high risk for cardiovascular events and mortality in the United States and Europe, but data from low-income countries and interventions to improve outcomes are lacking. METHODS: We conducted a 1-year prospective study of the prevalence and outcomes of hypertensive urgency (blood pressure (BP) ≥180 mm Hg/120 mm Hg without end-organ damage) in a busy outpatient clinic in Tanzania. RESULTS: Of 7,600 consecutive adult outpatients screened with 3 unattended automated BP measurements according to standard protocol, the prevalence of hypertensive crisis was 199/7,600 (2.6%) (BP ≥180 mm Hg/120 mm Hg) and the prevalence of hypertensive urgency was 164/7,600 (2.2%). Among 150 enrolled patients with hypertensive urgency, median age was 62 years (54-68), 101 (67.3%) were women, and 53 (35%) were either hospitalized or died within 1 year. In a multivariate model, the strongest predictor of hospitalization/death was self-reported medication adherence on a 3 question scale (hazard ratio: 0.06, P < 0.001); 90% of participants with poor adherence were hospitalized or died within 1 year. CONCLUSIONS: Patients with hypertensive urgency in Africa are at high risk of poor outcomes. Clinicians can identify the patients at highest risk for poor outcomes with simple questions related treatment adherence. New interventions are needed to improve medication adherence in patients with hypertensive urgency.


Asunto(s)
Hospitalización/estadística & datos numéricos , Hipertensión Maligna/epidemiología , Hipertensión/epidemiología , Cumplimiento de la Medicación/estadística & datos numéricos , Mortalidad , Anciano , Instituciones de Atención Ambulatoria , Antihipertensivos/uso terapéutico , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Tanzanía/epidemiología
7.
J Med Food ; 23(8): 870-878, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32609563

RESUMEN

We sought to investigate the effect of extracts from Rosa gallica petals (RPE) on skin whitening and anti-wrinkle activity. Tyrosinase activity was attenuated by RPE treatment, concomitant with the reduction of melanin accumulation in human B16F10 melanoma. Treatment of the facial skin of volunteers in a clinical trial with an RPE-containing formulation enhanced skin brightness (L* value) significantly. The underlying mechanism responsible was determined to be associated with mitogen-activated protein kinase (MAPK) activation. In addition, RPE exhibited anti-wrinkle formation activity of human dermal fibroblasts by suppressing matrix metalloproteinase (MMP)-1 level. In vivo study, RPE also inhibited solar ultraviolet-stimulated MMP-1 level by c-Jun regulation. Overall, our findings indicate that RPE evokes skin whitening and anti-wrinkle formation activity by regulating intracellular signaling, supporting its utility as an ingredient for skin whitening and anti-wrinkle cosmetic products.


Asunto(s)
Extractos Vegetales/farmacología , Rosa/química , Envejecimiento de la Piel/efectos de los fármacos , Preparaciones para Aclaramiento de la Piel/farmacología , Piel/efectos de los fármacos , Células Cultivadas , Fibroblastos , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Metaloproteinasa 1 de la Matriz/metabolismo , Melaninas/metabolismo , Melanoma Experimental , Rayos Ultravioleta
8.
J Neurosci ; 39(50): 10081-10095, 2019 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-31672788

RESUMEN

Neurovascular coupling (NVC), the interaction between neural activity and vascular response, ensures normal brain function by maintaining brain homeostasis. We previously reported altered cerebrovascular responses during functional hyperemia in chronically stressed animals. However, the underlying neuronal-level changes associated with those hemodynamic changes remained unclear. Here, using in vivo and ex vivo experiments, we investigate the neuronal origins of altered NVC dynamics under chronic stress conditions in adult male mice. Stimulus-evoked hemodynamic and neural responses, especially beta and gamma-band local field potential activity, were significantly lower in chronically stressed animals, and the NVC relationship, itself, had changed. Further, using acute brain slices, we discovered that the underlying cause of this change was dysfunction of neuronal nitric oxide synthase (nNOS)-mediated vascular responses. Using FISH to check the mRNA expression of several GABAergic subtypes, we confirmed that only nNOS mRNA was significantly decreased in chronically stressed mice. Ultimately, chronic stress impairs NVC by diminishing nNOS-mediated vasodilation responses to local neural activity. Overall, these findings provide useful information in understanding NVC dynamics in the healthy brain. More importantly, this study reveals that impaired nNOS-mediated NVC function may be a contributory factor in the progression of stress-related diseases.SIGNIFICANCE STATEMENT The correlation between neuronal activity and cerebral vascular dynamics is defined as neurovascular coupling (NVC), which plays an important role for meeting the metabolic demands of the brain. However, the impact of chronic stress, which is a contributory factor of many cerebrovascular diseases, on NVC is poorly understood. We therefore investigated the effects of chronic stress on impaired neurovascular response to sensory stimulation and their underlying mechanisms. Multimodal approaches, from in vivo hemodynamic imaging and electrophysiology to ex vivo vascular imaging with pharmacological treatment, patch-clamp recording, FISH, and immunohistochemistry revealed that chronic stress-induced dysfunction of nNOS-expressing interneurons contributes to NVC impairment. These findings will provide useful information to understand the role of nNOS interneurons in NVC in normal and pathological conditions.


Asunto(s)
Circulación Cerebrovascular/fisiología , Neuronas GABAérgicas/fisiología , Interneuronas/fisiología , Acoplamiento Neurovascular/fisiología , Estrés Fisiológico/fisiología , Potenciales de Acción/fisiología , Animales , Encéfalo/fisiología , Masculino , Ratones , Óxido Nítrico Sintasa de Tipo I/metabolismo , Vasodilatación/fisiología
9.
Food Sci Biotechnol ; 28(5): 1439-1446, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31695942

RESUMEN

The anti-skin inflammatory activities of rose petal extracts have been described in our previous study. Because skin inflammation is closely linked to skin aging, our study investigated the effects of Rosa gallica petals on skin aging-related activities such as skin whitening and anti-wrinkle properties. Each sample was prepared via extraction using different ethanol ratios with the objective of evaluationg optimal extraction conditions for industrial application. Aqueous 50% (v/v) EtOH extract of R. gallica petal significantly suppressed tyrosinase activity, melanin production, and solar UV-induced matrix metalloproteinase-1, a hall mark of wrinkle formation. In addition, the aqueous 50% (v/v) EtOH extract showed the highest antioxidative effect and had highest flavonoid contents, consistent with the reported anti-aging effects. Overall, our findings suggest that R. gallica petals extracts exhibit anti-aging effects. Furthermore, 50% EtOH extraction, in particular, was optimal for the highest anti-aging, and anti-oxidative effects as well as to obtain the highest flavonoid content.

10.
Food Sci Nutr ; 6(8): 2560-2567, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30510758

RESUMEN

The aim of this study was to investigate the skin anti-inflammatory activity of rose petal extract (RPE) and the mechanisms underlying this phenomenon. Recently, flowers have been considered as dietary resources owing to their biological activities, such as inhibition of nephritis and hemorrhoids. The Rosa plant exerts various biological functions, including antioxidant and anti-microbiological activities. Herein, we confirmed the skin anti-inflammatory activity of RPE upon solar UV (sUV) exposure. RPE reduced sUV-induced COX-2 expression as well as expressions of several cytokines. Activation of MKK4-JNK, MEK-ERK, and MKK3-p38 signaling pathways, which are associated with cytokine production, was also attenuated by RPE treatment. We hypothesized these RPE-induced changes are because of its antioxidant activity, because RPE displayed drastic radical scavenging and oxygen radical absorbance capacity (ORAC). Furthermore, high anthocyanins, polyphenols, and flavonoids contents were found in RPE. Hence, these results indicated the skin anti-inflammatory activity of RPE is because of antioxidant activity.

11.
Nature ; 559(7713): 279-284, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29950726

RESUMEN

Accurate replication of DNA requires stringent regulation to ensure genome integrity. In human cells, thousands of origins of replication are coordinately activated during S phase, and the velocity of replication forks is adjusted to fully replicate DNA in pace with the cell cycle1. Replication stress induces fork stalling and fuels genome instability2. The mechanistic basis of replication stress remains poorly understood despite its emerging role in promoting cancer2. Here we show that inhibition of poly(ADP-ribose) polymerase (PARP) increases the speed of fork elongation and does not cause fork stalling, which is in contrast to the accepted model in which inhibitors of PARP induce fork stalling and collapse3. Aberrant acceleration of fork progression by 40% above the normal velocity leads to DNA damage. Depletion of the treslin or MTBP proteins, which are involved in origin firing, also increases fork speed above the tolerated threshold, and induces the DNA damage response pathway. Mechanistically, we show that poly(ADP-ribosyl)ation (PARylation) and the PCNA interactor p21Cip1 (p21) are crucial modulators of fork progression. PARylation and p21 act as suppressors of fork speed in a coordinated regulatory network that is orchestrated by the PARP1 and p53 proteins. Moreover, at the fork level, PARylation acts as a sensor of replication stress. During PARP inhibition, DNA lesions that induce fork arrest and are normally resolved or repaired remain unrecognized by the replication machinery. Conceptually, our results show that accelerated replication fork progression represents a general mechanism that triggers replication stress and the DNA damage response. Our findings contribute to a better understanding of the mechanism of fork speed control, with implications for genomic (in)stability and rational cancer treatment.


Asunto(s)
Estructuras Cromosómicas , Daño del ADN , Replicación del ADN/fisiología , Inestabilidad Genómica , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Línea Celular Tumoral , Estructuras Cromosómicas/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Daño del ADN/efectos de los fármacos , Replicación del ADN/efectos de los fármacos , Inestabilidad Genómica/efectos de los fármacos , Humanos , Ftalazinas/farmacología , Piperazinas/farmacología , Poli(ADP-Ribosa) Polimerasa-1/antagonistas & inhibidores , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Factores de Tiempo , Proteína p53 Supresora de Tumor/metabolismo
12.
Oxid Med Cell Longev ; 2018: 5967150, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29849904

RESUMEN

Kaempferia parviflora (Krachaidum (KD)) is a traditional herbal medicine and has properties that are beneficial for human health. In the current study, we sought to investigate the anti-inflammatory properties of KD extract (KPE). In mouse skin tissue, UV light representing solar wavelengths (sUV) increased COX-2 expression, while treatment with KPE reduced this effect. The anti-inflammatory activity of KPE was confirmed in in vitro models. MAPK signaling pathways were activated by sUV irradiation, and this was also repressed in the presence of KPE treatment. It is assumed that the anti-inflammatory activity of KPE is caused by the antioxidative effect. Furthermore, we confirmed the critical role of oxidative stress in sUV-induced COX-2 expression. We analyzed the polyphenol composition of KPE. Of the polyphenols identified, gallic acid, apigenin, and tangeretin were identified as the major polyphenols (at 9.31 ± 1.27, 2.37 ± 0.14, and 2.15 ± 0.19 µg/mg dry weight, resp.). Collectively, these findings show that in the presence of sUV irradiation, KD has anti-inflammatory properties and antioxidative effects in the skin.


Asunto(s)
Antioxidantes/uso terapéutico , Medicina de Hierbas/métodos , Zingiber officinale/química , Animales , Antioxidantes/farmacología , Humanos , Ratones
13.
J Ginseng Res ; 42(2): 165-174, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29719463

RESUMEN

BACKGROUND: Extended endoplasmic reticulum (ER) stress may initiate apoptotic pathways in cancer cells, and ER stress has been reported to possibly increase tumor death in cancer therapy. We previously reported that caspase-8 played an important role in compound K-induced apoptosis via activation of caspase-3 directly or indirectly through Bid cleavage, cytochrome c release, and caspase-9 activation in HL-60 human leukemia cells. The mechanisms leading to apoptosis in A549 and SK-MES-1 human lung cancer cells and the role of ER stress have not yet been understood. METHODS: The apoptotic effects of compound K were analyzed using flow cytometry, and the changes in protein levels were determined using Western blot analysis. The intracellular calcium levels were monitored by staining with Fura-2/AM and Fluo-3/AM. RESULTS: Compound K-induced ER stress was confirmed through increased phosphorylation of eIF2α and protein levels of GRP78/BiP, XBP-1S, and IRE1α in human lung cancer cells. Moreover, compound-K led to the accumulation of intracellular calcium and an increase in m-calpain activities that were both significantly inhibited by pretreatment either with BAPTA-AM (an intracellular Ca2+ chelator) or dantrolene (an RyR channel antagonist). These results were correlated with the outcome that compound K induced ER stress-related apoptosis through caspase-12, as z-ATAD-fmk (a specific inhibitor of caspase-12) partially ameliorated this effect. Interestingly, 4-PBA (ER stress inhibitor) dramatically improved the compound K-induced apoptosis. CONCLUSION: Cell survival and intracellular Ca2+ homeostasis during ER stress in human lung cancer cells are important factors in the induction of the compound K-induced apoptotic pathway.

14.
Oncol Lett ; 15(4): 6043-6049, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29556318

RESUMEN

A previous study reported that a novel dammarane-type triterpene saponin, ginsenoside-Rg18, derived from the root of Panax ginseng, displayed hydroxyl radical scavenging, anti-bacterial and cytotoxic activities. However, the underlying molecular mechanisms of its anti-proliferative effect on non-small cell lung cancer (NSCLC) A549 cells remains unclear. In the present study, it was determined that Rg18 inhibited the proliferation of A549 cells with a half-maximal inhibitory concentration of 150 µM. Flow cytometry analysis indicated that cell cycle progression was blocked by Rg18 at G1 phase in A549 cells, which was accompanied by downregulation of cyclin-dependent kinase 2 (CDK2), CDK4, CDK6, cyclin D1, cyclin D2, cyclin E and phosphorylated retinoblastoma protein expression at the protein level. In addition, the CDK inhibitors (CDKNs), CDKN1A and CDKN1B, were upregulated following Rg18 treatment. Furthermore, Rg18 treatment resulted in the intracellular accumulation of reactive oxygen species (ROS), and a dose-dependent inhibition of p38 mitogen activated protein kinase (p38), c-Jun N-terminal kinase (JNK) and nuclear factor-κB (NF-κB)/p65 phosphorylation. Taken together, Rg18-mediated G1 phase arrest was closely associated with the generation of intracellular ROS, and p38, JNK and NF-κB/p65 inhibition in A549 human NSCLC cells.

15.
Sensors (Basel) ; 18(1)2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29351218

RESUMEN

In this paper, we introduce a transparent fingerprint sensing system using a thin film transistor (TFT) sensor panel, based on a self-capacitive sensing scheme. An armorphousindium gallium zinc oxide (a-IGZO) TFT sensor array and associated custom Read-Out IC (ROIC) are implemented for the system. The sensor panel has a 200 × 200 pixel array and each pixel size is as small as 50 µm × 50 µm. The ROIC uses only eight analog front-end (AFE) amplifier stages along with a successive approximation analog-to-digital converter (SAR ADC). To get the fingerprint image data from the sensor array, the ROIC senses a capacitance, which is formed by a cover glass material between a human finger and an electrode of each pixel of the sensor array. Three methods are reviewed for estimating the self-capacitance. The measurement result demonstrates that the transparent fingerprint sensor system has an ability to differentiate a human finger's ridges and valleys through the fingerprint sensor array.

16.
J Ginseng Res ; 41(3): 428-433, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28701887

RESUMEN

BACKGROUND: In this study, the fermentation of ginseng seeds was hypothesized to produce useful physiologically-active substances, similar to that observed for fermented ginseng root. Ginseng seed was fermented using Bacillus, Pediococcus, and Lactobacillus strains to extract ginseng seed oil, and the extraction yield, color, and quantity of phenolic compounds, fatty acids, and phytosterol were then analyzed. METHODS: The ginseng seed was fermented inoculating 1% of each strain on sterilized ginseng seeds and incubating the seeds at 30°C for 24 h. Oil was extracted from the fermented ginseng seeds using compression extraction, solvent extraction, and supercritical fluid extraction. RESULTS AND CONCLUSION: The color of the fermented ginseng seed oil did not differ greatly according to the fermentation or extraction method. The highest phenolic compound content recovered with the use of supercritical fluid extraction combined with fermentation using the Bacillus subtilis Korea Food Research Institute (KFRI) 1127 strain. The fatty acid composition did not differ greatly according to fermentation strain and extraction method. The phytosterol content of ginseng seed oil fermented with Bacillus subtilis KFRI 1127 and extracted using the supercritical fluid method was highest at 983.58 mg/100 g. Therefore, our results suggested that the ginseng seed oil fermented with Bacillus subtilis KFRI 1127 and extracted using the supercritical fluid method can yield a higher content of bioactive ingredients, such as phenolics, and phytosterols, without impacting the color or fatty acid composition of the product.

17.
Oncol Rep ; 36(6): 3577-3587, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27748905

RESUMEN

Previously, we reported that (E)-8-acetoxy-2-[2-(3,4-diacetoxyphenyl)ethenyl]-quinazoline (8-ADEQ), a synthetic analogue of resveratrol had anti-inflammatory and G2/M cell cycle arrest activities, but the underlying molecular mechanism of cytotoxic effects of this compound was not determined. In this study, 8-ADEQ displayed potent cytotoxicity and triggered apoptosis in HL-60 cells as evidenced by DNA fragmentation, DNA ladder formation, and the externalization of Annexin V-targeted phosphatidylserine residues in HL-60 cells. In addition, 8-ADEQ triggered activation of caspases-8, -9, -6 and -3 and cleavage of their substrates such as poly(ADP-ribose) polymerase (PARP). Moreover, 8-ADEQ induced loss of mitochondrial membrane potential (MMP) and release of cytochrome c to the cytosol. Caspase-3 inhibitor (z-DEVD-fmk), caspase-8 inhibitor (z-IETD-fmk), caspase-9 inhibitor (z-LEHD), and broad caspase inhibitor (z-VAD­fmk) significantly suppressed the 8-ADEQ-induced DNA fragmentation. Interestingly, pretreatment with z-IETD-fmk, a caspase-8 inhibitor, completely abolished 8-ADEQ-induced caspase-3 and -9 activation, and subsequent DNA fragmentation. 8-ADEQ also increased the expression of Fas, Fas-associated death domain (FADD) and FasL, and formation of death-inducing signaling complex (DISC). Further analysis revealed that 8-ADEQ-induced apoptosis was mediated by upregulation of reactive oxidative species (ROS) generation. Taken together, our data indicated that 8-ADEQ-stimulated apoptosis in HL-60 leukemia cells is due to a Fas-mediated caspase-8-dependent pathway via ROS generation, but also, to a lesser extent cytochrome c release and caspase-9 activation.


Asunto(s)
Apoptosis/efectos de los fármacos , Quinazolinas/farmacología , Estilbenos/farmacología , Clorometilcetonas de Aminoácidos , Caspasa 3/metabolismo , Caspasa 8/metabolismo , Caspasa 9/metabolismo , Inhibidores de Caspasas/farmacología , Citocromos c/metabolismo , Proteína Ligando Fas , Células HL-60 , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Oligopéptidos , Poli(ADP-Ribosa) Polimerasas/metabolismo , Resveratrol
18.
PLoS One ; 11(10): e0164924, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27741289

RESUMEN

PURPOSE: To identify the impact of reconstruction algorithms on CT radiomic features of pulmonary tumors and to reveal and compare the intra- and inter-reader and inter-reconstruction algorithm variability of each feature. METHODS: Forty-two patients (M:F = 19:23; mean age, 60.43±10.56 years) with 42 pulmonary tumors (22.56±8.51mm) underwent contrast-enhanced CT scans, which were reconstructed with filtered back projection and commercial iterative reconstruction algorithm (level 3 and 5). Two readers independently segmented the whole tumor volume. Fifteen radiomic features were extracted and compared among reconstruction algorithms. Intra- and inter-reader variability and inter-reconstruction algorithm variability were calculated using coefficients of variation (CVs) and then compared. RESULTS: Among the 15 features, 5 first-order tumor intensity features and 4 gray level co-occurrence matrix (GLCM)-based features showed significant differences (p<0.05) among reconstruction algorithms. As for the variability, effective diameter, sphericity, entropy, and GLCM entropy were the most robust features (CV≤5%). Inter-reader variability was larger than intra-reader or inter-reconstruction algorithm variability in 9 features. However, for entropy, homogeneity, and 4 GLCM-based features, inter-reconstruction algorithm variability was significantly greater than inter-reader variability (p<0.013). CONCLUSIONS: Most of the radiomic features were significantly affected by the reconstruction algorithms. Inter-reconstruction algorithm variability was greater than inter-reader variability for entropy, homogeneity, and GLCM-based features.


Asunto(s)
Algoritmos , Neoplasias Pulmonares/diagnóstico por imagen , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
19.
Infect Chemother ; 48(1): 20-30, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27104012

RESUMEN

BACKGROUND: Travel-related risks for infectious diseases vary depending on travel patterns such as purpose, destination, and duration. In this study, we describe the patterns of travel and prescription of vaccines as well as malaria prophylaxis medication (MPM) at a travel clinic in South Korea to identify the gaps to fill for the optimization of pre-travel consultation. MATERIALS AND METHODS: A cohort of travel clinic visitors in 2011 was constructed and early one-third of the visitors of each month were reviewed. During the study period, 10,009 visited the travel clinic and a retrospective chart review was performed for 3,332 cases for analysis of travel patterns and prescriptions. RESULTS: People receiving yellow fever vaccine (YFV) (n = 2,933) were traveling more frequently for business and tourism and less frequently for providing non-medical service or research/education compared to the 399 people who did not receive the YFV. Overall, most people were traveling to Eastern Africa, South America, and Western Africa, while South-Eastern Asia was the most common destination for the non-YFV group. Besides YFV, the typhoid vaccine was the most commonly prescribed (54.2%), while hepatitis A presented the highest coverage (74.7%) considering the natural immunity, prior and current vaccination history. Additionally, 402 (82.5%) individuals received a prescription for MPM among the 487 individuals travelling to areas with high-risk of malaria infection. Age over 55 was independently associated with receiving MPM prescription, while purpose of providing service and travel duration over 10 days were associated with no MPM prescription, despite travelling to high-risk areas. CONCLUSION: Eastern Africa and South America were common travel destinations among the visitors to a travel clinic for YFV, and most of them were travelling for tourism and business. For the individuals who are traveling to areas with high-risk for malaria, more proactive approach might be required in case of younger age travelers, longer duration, and travel purpose of providing service to minimize the risk of malaria infection.

20.
J Ginseng Res ; 39(2): 178-82, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26045692

RESUMEN

BACKGROUND: Fermentation technology is widely used to alter the effective components of ginseng. This study was carried out to analyze the characteristics and antioxidant activity of ginseng seeds fermented by Bacillus, Lactobacillus, and Pediococcus strains. METHODS: For ginseng seed fermentation, 1% of each strain was inoculated on sterilized ginseng seeds and then incubated at 30°C for 24 h in an incubator. RESULTS: The total sugar content, acidic polysaccharides, and phenolic compounds, including p-coumaric acid, were higher in extracts of fermented ginseng seeds compared to a nonfermented control, and highest in extracts fermented with B. subtilis KFRI 1127. Fermentation led to higher antioxidant activity. The 2,2'-azine-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity was higher in ginseng seeds fermented by Bacillus subtilis than by Lactobacillus and Pediococcus, but Superoxide dismutase (SOD) enzyme activity was higher in ginseng seeds fermented by Lactobacillus and Pediococcus. CONCLUSION: Antioxidant activities measured by ABTS and SOD were higher in fermented ginseng seeds compared to nonfermented ginseng seeds. These results may contribute to improving the antioxidant activity and quality of ginseng subjected to fermentation treatments.

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