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Despite significant improvements in vaccines and chemotherapeutic drugs, pathogenic RNA viruses continue to have a profound impact on the global economy and pose a serious threat to animal and human health through emerging and re-emerging outbreaks of diseases. To overcome the challenge of viral adaptation and evolution, increased vigilance is required. Particularly, antiviral drugs derived from new, natural sources provide an attractive strategy for controlling problematic viral diseases. In this antiviral study, we discovered a previously unknown bacterium, Mameliella sp. M20D2D8, by conducting an antiviral screening of marine microorganisms. An extract from M20D2D8 exhibited antiviral activity with low cytotoxicity and was found to be effective in vitro against multiple influenza virus strains: A/PR8 (IC50 = 2.93 µg/mL, SI = 294.85), A/Phil82 (IC50 = 1.42 µg/mL, SI = 608.38), and B/Yamagata (IC50 = 1.59 µg/mL, SI = 543.33). The antiviral action was found to occur in the post-entry stages of viral replication and to suppress viral replication by inducing apoptosis in infected cells. Moreover, it efficiently suppressed viral genome replication, protein synthesis, and infectivity in MDCK and A549 cells. Our findings highlight the antiviral capabilities of a novel marine bacterium, which could potentially be useful in the development of drugs for controlling viral diseases.
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Herpesvirus Cercopitecino 1 , Influenza Humana , Viroses , Animais , Humanos , Influenza Humana/tratamento farmacológico , Antivirais/farmacologia , Extratos Vegetais/farmacologia , Replicação ViralRESUMO
Anithiactin D (1), a 2-phenylthiazole class of natural products, was isolated from marine mudflat-derived actinomycetes Streptomyces sp. 10A085. The chemical structure of 1 was elucidated based on the interpretation of NMR and MS data. The absolute configuration of 1 was determined by comparing the experimental and calculated electronic circular dichroism (ECD) spectral data. Anithiactin D (1) significantly decreased cancer cell migration and invasion activities at a concentration of 5 µM via downregulation of the epithelial-to-mesenchymal transition (EMT) markers in A549, AGS, and Caco-2 cell lines. Moreover, 1 inhibited the activity of Rho GTPases, including Rac1 and RhoA in the A549 cell line, suppressed RhoA in AGS and Caco-2 cell lines, and decreased the mRNA expression levels of some matrix metalloproteinases (MMPs) in AGS and Caco-2 cell lines. Thus 1, which is a new entity of the 2-phenylthiazole class of natural products with a unique aniline-indole fused moiety, is a potent inhibitor of the motility of cancer cells.
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Neoplasias , Streptomyces , Humanos , Linhagem Celular Tumoral , Células CACO-2 , Streptomyces/metabolismo , Células A549 , Proteínas rho de Ligação ao GTP/metabolismo , Movimento Celular , Transição Epitelial-MesenquimalRESUMO
Lipid accumulation in microalgae can be substantially enhanced by exposing the microalgae to abiotic stress, thus increasing biofuel production. However, this also generates reactive oxygen species (ROS), which disrupts cell metabolism and reduces their productivity. Previous mRNA sequencing analyses in Neopyropia yezoensis and its associated microorganisms elucidated a putative glutathione peroxidase (PuGPx) gene. Here, this putative glutathione peroxidase was overexpressed in the microalga Chlamydomonas reinhardtii, which increased cell growth and survival rates compared to the control group under abiotic stress. Additionally, increased lipid accumulation was observed under salinity stress, high-temperature stress, and hydrogen peroxide (H2O2)-induced oxidative stress. These results suggest that PuGPx plays a protective role against abiotic stress in C. reinhardtii and stimulates lipid accumulation, which could be considered advantageous in terms of biofuel production.
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Chlamydomonas , Chlamydomonas/genética , Chlamydomonas/metabolismo , Glutationa Peroxidase/metabolismo , Biocombustíveis , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Estresse Fisiológico , LipídeosRESUMO
The AIM2 inflammasome is an innate immune system component that defends against cytosolic bacteria and DNA viruses, but its aberrant activation can lead to the progression of various inflammatory diseases, including psoriasis. However, there have been few reports of specific inhibitors of AIM2 inflammasome activation. In this study, we aimed to investigate the inhibitory activity of ethanolic extracts of seeds of Cornus officinalis (CO), a herb and food plant used in traditional medicine, on AIM2-inflammasome activation. We found that CO inhibited the release of IL-1ß induced by dsDNA in both BMDMs and HaCaT cells, but that it showed no effect on the release of IL-1ß induced by NLRP3 inflammasome triggers, such as nigericin and silica, or the NLRC4 inflammasome trigger flagellin. Furthermore, we demonstrated that CO inhibited the cleavage of caspase-1, an inflammasome activation marker, and an upstream event, the translocation and speck formation of ASC. In addition, further experiments and mechanistic investigations revealed that CO can inhibit AIM2 speck formation induced by dsDNA in AIM2-overexpressing HEK293T cells. To verify the correlation in vivo, we investigated the efficacy of CO in an imiquimod (IMQ)-induced psoriasis model, which has reported associations with the AIM2 inflammasome. We found that topical application of CO alleviated psoriasis-like symptoms, such as erythema, scaling, and epidermal thickening, in a dose-dependent manner. Moreover, CO also significantly decreased IMQ-induced expression of AIM2 inflammasome components, including AIM2, ASC, and caspase-1, and led to the elevation of serum IL-17A. In conclusion, our results suggest that CO may be a valuable candidate for the discovery of AIM2 inhibitors and the regulation of AIM2-related diseases.
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Cornus , Dermatite , Psoríase , Humanos , Inflamassomos/metabolismo , Imiquimode/efeitos adversos , Células HEK293 , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Inflamação , Extratos Vegetais/efeitos adversos , Sementes/metabolismo , Caspases , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Interleucina-1beta/metabolismo , Caspase 1/metabolismo , Proteínas de Ligação a DNA/metabolismoRESUMO
Avobenzone is the most commonly used ultraviolet (UV) A filter ingredient in sunscreen. To investigate the biological activity of avobenzone in normal human epidermal keratinocytes (NHEKs), the genome-scale transcriptional profile of NHEKs was performed. In this microarray study, we found 273 up-regulated and 274 down-regulated differentially expressed genes (DEGs) in NHEKs treated with avobenzone (10 µM). Gene Ontology (GO) enrichment analysis showed that avobenzone significantly increased the DEGs associated with lipid metabolism in NHEKs. In addition, avobenzone increased the gene transcription of peroxisome proliferator-activated receptor γ (PPARγ) and fatty acid binding protein 4 in NHEKs, implicating that avobenzone may be one of the metabolic disrupting obesogens. To confirm the obesogenic potential, we examined the effect of avobenzone on adipogenesis in human bone marrow mesenchymal stem cells (hBM-MSCs). Avobenzone (EC50, 14.1 µM) significantly promoted adipogenesis in hBM-MSCs as its positive control obesogenic chemicals. Avobenzone (10 µM) significantly up-regulated mRNA levels of PPARγ during adipogenesis in hBM-MSCs. However, avobenzone did not directly bind to PPARγ and the avobenzone-induced adipogenesis-promoting activity was not affected by PPARγ antagonists T0070907 and GW9662. Therefore, avobenzone promoted adipogenesis in hBM-MSCs through a PPARγ-independent mechanism. This study suggests that avobenzone functions as a metabolic disrupting obesogen.
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Adipogenia/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Propiofenonas/toxicidade , Protetores Solares/toxicidade , Transcrição Gênica/efeitos dos fármacos , Adipogenia/genética , Animais , Regulação para Baixo , Estudo de Associação Genômica Ampla , Humanos , Queratinócitos/citologia , Células-Tronco Mesenquimais/citologia , Nível de Efeito Adverso não Observado , Fenótipo , Ratos Sprague-Dawley , Testes de Toxicidade Aguda , Regulação para CimaRESUMO
Copper metallization is a key issue for high performance thin film transistor technology. Hydrogen peroxide-based copper etchants are widely used in copper metallization. Recently, a hydrogen peroxide-based copper etchant for a copper/molybdenum double layer was investigated for its versatile use in both amorphous silicon TFTs and in metal-oxide TFTs. However, little is known about the etching mechanism for molybdenum and copper in a hydrogen peroxide solution containing fluorine ions. In this paper, it is shown that the amount of fluorine ions in the hydrogen peroxide-based copper etchant plays an important role in controlling the galvanic reaction between the copper and the molybdenum. A new mechanism of molybdenum dissolution in the presence of fluoride ions in 1.5 M hydrogen peroxide solution is suggested. The concentration of the fluoride ions is also important in eliminating the residue of molybdenum after wet patterning.
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Endothelial cells (ECs) maintain the structure and function of blood vessels and are readily exposed to exogenous and endogenous toxic substances in the circulatory system. Bone marrow-derived endothelial progenitor cells (EPCs) circulate in the blood and differentiate to EC, which are known to participate in angiogenesis and regeneration of injured vessels. Dysfunction in EPC contributes to cardiovascular complications in patients with diabetes, but the precise molecular mechanisms underlying diabetic EPC abnormalities are not completely understood. The aim of this study was to investigate the mechanisms underlying diabetic EPC dysfunction using methylglyoxal (MG), an endogenous toxic diabetic metabolite. Data demonstrated that MG decreased cell viability and protein expression of vascular endothelial growth factor receptor (VEGFR)-2 associated with functional impairment of tube formation in EPC. The generation of advanced glycation end (AGE) products was increased in EPC following exposure to MG. Blockage of receptor for AGE (RAGE) by FPS-ZM1, a specific antagonist for RAGE, significantly reversed the decrease of VEGFR-2 protein expression and angiogenic dysfunction in MG-incubated EPC. Taken together, data demonstrated that MG induced angiogenic impairment in EPC via alterations in the AGE/RAGE-VEGFR-2 pathway which may be utilized in the development of potential therapeutic and preventive targets for diabetic vascular complications.
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Inibidores da Angiogênese/metabolismo , Células Progenitoras Endoteliais/efeitos dos fármacos , Produtos Finais de Glicação Avançada/farmacologia , Substâncias Perigosas/toxicidade , Aldeído Pirúvico/toxicidade , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Medula Óssea/fisiologia , Células Progenitoras Endoteliais/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
A phase change nanowire holds a promise for nonvolatile memory applications, but its transition mechanism has remained unclear due to the analytical difficulties at atomic resolution. Here we obtain a deeper understanding on the phase transition of a single crystalline Ge2Sb2Te5 nanowire (GST NW) using atomic scale imaging, diffraction, and chemical analysis. Our cross-sectional analysis has shown that the as-grown hexagonal close-packed structure of the single crystal GST NW transforms to a metastable face-centered cubic structure due to the atomic migration to the pre-existing vacancy layers in the hcp structure going through iterative electrical switching. We call this crystal structure transformation "metastabilization", which is also confirmed by the increase of set-resistance during the switching operation. For the set to reset transition between crystalline and amorphous phases, high-resolution imaging indicates that the longitudinal center of the nanowire mainly undergoes phase transition. According to the atomic scale analysis of the GST NW after repeated electrical switching, partial crystallites are distributed around the core-centered amorphous region of the nanowire where atomic migration is mainly induced, thus potentially leading to low power electrical switching. These results provide a novel understanding of phase change nanowires, and can be applied to enhance the design of nanowire phase change memory devices for improved electrical performance.
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This study was conducted to assess the relationship between body composition and suicidal ideation among the Korean elderly population (n = 302; ≥ 65 years) who participated in the Hallym Aging Study in 2010. Body composition was measured using dual-energy X-ray absorptiometry, and obesity was measured by the indices of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), and body fat percentage. Sarcopenia was defined as presence of both low muscle mass and low muscle function. Suicidal ideation was assessed using the Beck Scale for Suicide Ideation. We found no differences in body composition measures between subjects with suicidal ideation and those without. In the logistic regression analyses, there were no significant relationships for suicidal ideation according to body composition measures, including BMI, WC, WHR, WHtR, and body fat percentage in both sexes. After adjusting for age, smoking status, alcohol drinking, regular exercise, medical comorbidities, monthly income, education level, and presence of depressive symptoms, the odds ratio (OR) of suicidal ideation was higher in elderly men with sarcopenia compared to those without, whereas no significant relationships were observed in elderly women (OR 8.28, 95% confidence interval [CI] 1.20-61.34 in men; OR 0.79, 95% CI 0.07-8.43 in women). Sarcopenia is closely associated with an increased risk of suicidal ideation in elderly men.
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Envelhecimento , Composição Corporal , Sarcopenia/diagnóstico , Ideação Suicida , Idoso , Povo Asiático , Estatura , Índice de Massa Corporal , Depressão/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Obesidade/epidemiologia , Razão de Chances , República da Coreia , Sarcopenia/psicologia , Circunferência da Cintura , Relação Cintura-QuadrilRESUMO
Emerging photonic integrated circuit technologies require integrative functionality at ultrahigh speed and dimensional compatibility with ultrasmall electronics. Plasmonics offers a promise of addressing these challenges with novel nanophotonic approaches for on-chip information processing or sensing applications. Short communication range and strong light-matter interaction enabled by on-chip plasmonics allow us to extend beyond a conventional approach of integrating coherent and narrowband light source. Such hybrid electronic and photonic interconnection desires a on-chip photodetector that is highly responsive to broadband incoherent light, yet provides elegant design for nanoscale integration. Here we demonstrate an ultracompact broadband photodetection with greatly enhanced photoresponsivity using plasmonic nanoridge geometry. The nanoridge photodetector confines a wide spectrum of electromagnetic energy in a nanostructure through the excitation of multiple plasmons, which thus enables the detection of weak and broadband light. With nanoscale design, material, and dimensional compatibility for the integration, the nanoridge photodetector opens up a new possibility of highly sensitive on-chip photodetection for future integrated circuits and sensing applications.
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This study was conducted to assess the association between sarcopenic obesity and cardiovascular disease (CVD) risk in Korean adults (n=3,320; ≥40 yr) who participated in the 5th Korean National Health and Nutrition Examination Survey in 2010. The appendicular skeletal muscle mass divided by body weight was calculated for each participant; participants with values <1 standard deviation below the mean reference value (i.e., aged 20-39 yr) were considered sarcopenic. Subjects were further classified into 4 groups according to their obesity (i.e., body mass index ≥25 kg/m(2)) and sarcopenic status. Individuals' 10-yr CVD risk was determined using the Framingham risk model. The sarcopenic obese group had more participants (43.8% men, 14.6% women) with a high risk of CVD (≥20%). The sarcopenic obese group was associated with an increased 10-yr CVD risk than the non-sarcopenic, non-obese group (odds ratio [OR], 2.49; 95% confidence interval [CI], 1.53-4.06, P<0.001 in men; OR, 1.87; 95% CI, 1.02-3.41, P=0.041 in women). Sarcopenic non-obese and non-sarcopenic obese subjects were not associated with an increased 10-yr CVD risk. Sarcopenic obesity, but not non-sarcopenic obesity, was closely associated with an increased CVD risk in Korean adults.
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Doenças Cardiovasculares/epidemiologia , Músculo Esquelético/fisiologia , Obesidade/epidemiologia , Sarcopenia/epidemiologia , Envelhecimento , Composição Corporal/fisiologia , Índice de Massa Corporal , Peso Corporal , Estudos Transversais , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Fatores de Risco , Fatores SexuaisRESUMO
This study investigates the effect of a high-temperature annealing process on the characteristics and performance of a memristor based on a Ag/Ga2O3/Pt structure. Through X-ray diffraction analysis, successful phase conversion from amorphous Ga2O3 to ß-Ga2O3 is confirmed, attributed to an increase in grain size and recrystallization induced by annealing. X-ray photoelectron spectroscopy analysis revealed a higher oxygen vacancy in annealed Ga2O3 thin films, which is crucial for conductive filament formation and charge transport in memristors. Films with abundant oxygen vacancies exhibit decreased set voltages and increased capacitance in a low-resistive state, enabling easy capacitance control depending on channel presence. In addition, an excellent memory device with a high on/off ratio can be implemented due to the reduction of leakage current due to recrystallization. Therefore, it is possible to manufacture a thin film suitable for a memristor by increasing the oxygen vacancy in the Ga2O3 film while improving the overall crystallinity through the annealing process. This study highlights the significance of annealing in modulating capacitance and high-resistive/low-resistive state properties of Ga2O3 memristors, contributing to optimizing device design and performance. This study underscores the significance of high-temperature annealing in improving the channel-switching characteristics of Ga2O3-based memristors, which is crucial for the development of low-power, high-efficiency memory device.
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INTRODUCTION: Muscle strength is known to play an important role in the health of older adults. The health burden of cigarette smoking among older adults remains significant. We investigated the association between smoking cessation and dynapenia among older lifetime smokers in Korea. METHODS: This study is a secondary dataset analysis of cross-sectional data from theKorea National Health and Nutrition Examination Survey (KNHANES) 2016- 2019. We included 1450 participants aged 65-79 years, excluding those who had never smoked. Dynapenia was defined as grip strength <28 kg for men and <18 kg for women based on the Asian Working Group for Sarcopenia 2019 criteria. Multivariable logistic regression analysis evaluated the association between smoking cessation and dynapenia. RESULTS: Compared with current smokers, the adjusted odds ratio (AOR) of dynapenia in former smokers was 0.66 (95% CI: 0.44-0.99). The AORs for smoking cessation periods of ≤10 years, 10-20 years, 20-30 years, and >30 years were 0.67 (95% CI: 0.39-1.16), 0.61 (95% CI: 0.36-1.03), 0.65 (95% CI: 0.37-1.14), and 0.52 (95% CI: 0.25-1.06), respectively. The AOR for dynapenia significantly decreased with the years since smoking cessation (p for trend=0.043). CONCLUSIONS: Our findings suggest that smoking cessation can reduce the likelihood of dynapenia among older lifetime smokers, with a decreasing likelihood trend associated with longer cessation periods.
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Caffeine is present in various foods and medicines and is highly accessible through various routes, regardless of age. However, most studies on caffeine have focused on the effects of high-dose caffeine ingestion based on the recommended daily amount for adults. In this study, we examined the physiological changes in the central and peripheral vessels that may occur when ingesting low-dose caffeine due to its high accessibility, with the aim of creating an environment of safe caffeine ingestion. This study included 26 healthy participants in their 20s. Peak systolic velocity (PSV), heart rate (HR), and pulse wave velocity (PWV) for vascular stiffness assessment were measured at 0, 30, and 60 min after caffeine ingestion using diagnostic ultrasound to determine the physiological changes in the blood vessels, common carotid artery (CCA) and radial artery (RA). In addition, percutaneous oxygen saturation (SpO2), blood pressure (BP), and accelerated photoplethysmography (APG) were measured. In comparison with before ingestion, the HR tended to decrease and showed a significant difference at 30 and 60 min (p = 0.014 and p = 0.031, respectively). PSV significantly decreased in both vessels at 30 and 60 min (p < 0.001 and p < 0.001, respectively). APG showed a decreasing trend until 60 min after ingestion, with a significant difference at 30 and 60 min (p = 0.003 and p = 0.012, respectively). No significant difference was observed in SpO2, BP, or PWV; however, they showed a tendency to increase after ingestion. Decreased HR may occur because of the baroreflex caused by an increase in BP. The RA has many branches and a smaller diameter; therefore, the PSV was lower in the RA than that in the CCA. This effect can occur because of the difficulty in the smooth expansion of blood vessels, which leads to a decrease in blood flow. In addition, an increase in intracellular calcium concentration can prevent vasodilation and increase the propagation velocity of pulse waves. The reflected waves can increase systolic blood pressure but reduce PWV and vascular elasticity. These results suggest that even low-dose caffeine can improve blood vessel health by providing temporary stimulation to the blood vessels; however, it can also cause changes in blood flow and blood vessel elasticity, which can lead to serious diseases such as stroke and high blood pressure. Therefore, caution should be exercised when caffeine consumption is indiscriminate.
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Cafeína , Análise de Onda de Pulso , Adulto , Humanos , Ultrassonografia , Artéria Radial , Ingestão de AlimentosRESUMO
Colorectal cancer (CRC) is the second most common cause of cancer-related death and represents a serious worldwide health problem. CRC metastasis decreases the survival rate of cancer patients, underscoring the need to identify novel anticancer agents and therapeutic targets. Here, we introduce Plectalibertellenone A (B) as a promising agent for the inhibition of CRC cell motility and glucose metabolism and explore its mechanism of action in CRC cells. Plectalibertellenone A suppressed TGF-ß gene expression and the activation of the TGF-ß/Smad signaling pathway, leading to reverse epithelial to mesenchymal transition (EMT) by modulating the expressions of EMT markers and transcriptional factors such as E-cadherin, N-cadherin, vimentin, Slug, Snail, Twist, and ZEB1/2. Furthermore, disruption of Wnt signaling inhibited CRC motility and glucose metabolism including glycolysis and oxidative phosphorylation, primarily affecting glycolytic enzymes, GLUT1, HK2, PKM2, LDHA, and HIF-1α under hypoxic condition. Therefore, Plectalibertellenone A is a potential drug candidate that can be developed into a promising anticancer treatment to prevent CRC metastasis and inhibit glucose metabolism.
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AIMS: To investigate risk factors for cesarean section (CS) following labor induction in nulliparas with an unfavorable cervix at or beyond 41 weeks of gestation. METHODS: In this retrospective cohort study, a total of 276 nulliparas with an unfavorable cervix (Bishop score ≤6) who underwent labor induction for prolonged pregnancies were included out of a total of 646 patients who delivered ≥41 weeks (2002-2011). RESULTS: 82 (29.7%) patients of the 276 delivered by CS. The patients who underwent CS had less cervical dilatation and a lower Bishop score on admission than those patients who delivered vaginally (0.76 ± 0.47 vs. 0.92 ± 0.58 cm, p = 0.03 and 1.16 ± 1.25 vs. 1.51 ± 1.34, p = 0.04, respectively). Neonatal birth weight and biparietal diameter (BPD) were significantly smaller in the vaginal delivery group (3,414.93 ± 361.37 vs. 3,534.81 ± 383.05 g, p = 0.01 and 9.43 ± 0.35 vs. 9.65 ± 0.42 cm, p < 0.01). After multiple logistic regression analysis, maternal height, BPD, and early rupture of membranes (ROM) were independently related with CS. Early ROM was defined as spontaneous ROM that occurred before the onset of the active phase of labor. CONCLUSION: Maternal height, BPD, and early ROM were risk factors for CS following labor induction in nulliparas at or beyond 41 weeks of gestation.
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Cesárea , Idade Gestacional , Primeira Fase do Trabalho de Parto , Trabalho de Parto Induzido , Adulto , Peso ao Nascer , Estatura , Colo do Útero , Estudos de Coortes , Feminino , Ruptura Prematura de Membranas Fetais , Humanos , Recém-Nascido , Modelos Logísticos , Paridade , Gravidez , Gravidez Prolongada/prevenção & controle , Gravidez Prolongada/terapia , Estudos Retrospectivos , Fatores de RiscoAssuntos
Queloide , Dosagem Radioterapêutica , Orelha Externa , Humanos , Radioterapia Adjuvante , RecidivaRESUMO
Microalgae are attracting much attention as promising, eco-friendly producers of bioenergy due to their fast growth, absorption of carbon dioxide from the atmosphere, and production capacity in wastewater and salt water. However, microalgae can only accumulate large quantities of lipid in abiotic stress, which reduces productivity by decreasing cell growth. In this study, the strategy was investigated to increase cell viability and lipid production by overexpressing S-adenosylmethionine (SAM) synthetase (SAMS) in the microalga Chlamydomonas reinhardtii. SAM is a substance that plays an important role in various intracellular biochemical reactions, such as cell proliferation and stress response, and the overexpression of SAMS could allow cells to withstand the abiotic stress and increase productivity. Compared to wild-type C. reinhardtii, recombinant cells overexpressing SAMS grew 1.56-fold faster and produced 1.51-fold more lipids in a nitrogen-depleted medium. Furthermore, under saline-stress conditions, the survival rate and lipid accumulation were 1.56 and 2.04 times higher in the SAMS-overexpressing strain, respectively. These results suggest that the overexpression of SAMS in recombinant C. reinhardtii has high potential in the industrial-scale production of biofuels and various other high-value-added materials.
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Chlamydomonas reinhardtii , Chlamydomonas , Lipídeos , Metionina Adenosiltransferase , Chlamydomonas reinhardtii/química , Proliferação de CélulasRESUMO
We studied on the bipolar resistive switching (RS)-dependent capacitance of Ga2O3 memristors, grown using controlled oxygen flow via a radio frequency sputtering process. The Ag/Ga2O3/Pt memristor structure was employed to investigate the capacitance changes associated with RS behavior and oxygen concentration. In the low-resistance state (LRS), capacitance increased by over 60 times compared to the high-resistance state (HRS). Furthermore, in the HRS state, increasing the oxygen flow from 0 to 0.3 sccm resulted in an 80 % decrease in capacitance, while in the LRS state, capacitance increased by 128 %. These results indicate that RS-dependent capacitance in Ga2O3 memristors is influenced by the density of oxygen vacancies. The presence of oxygen vacancies affects charge storage capacity and capacitance, with higher oxygen concentrations leading to reduced capacitance in HRS and increased capacitance in LRS. The results contribute to the understanding of the capacitance behavior in Ga2O3 memristors and highlight the significance of oxygen vacancies in their operation.