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1.
Breast Cancer Res Treat ; 206(1): 31-44, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38743175

RESUMEN

PURPOSE: This single-center, randomized, prospective, exploratory clinical trial was conducted to assess the clinical efficacy of an augmented reality (AR)-based breast cancer localization imaging solution for patients with breast cancer. METHODS: This clinical trial enrolled 20 women who were diagnosed with invasive breast cancer between the ages of 19 and 80, had a single lesion with a diameter ≥ 5 mm but ≤ 30 mm, had no metastases to other organs, and had not received prior chemotherapy. All patients underwent mammography, ultrasound, computed tomography, and magnetic resonance imaging for preoperative assessment. Patients were randomly assigned to ultrasound-guided skin marking localization (USL) and AR-based localization (ARL) groups (n = 10 in each group). Statistical comparisons between USL and ARL groups were made based on demographics, radiologic features, pathological outcomes, and surgical outcomes using chi-square and Student t-tests. RESULTS: Two surgeons performed breast-conserving surgery on 20 patients. Histopathologic evaluation of all patients confirmed negative margins. Two independent pathologists evaluated the marginal distances, and there were no intergroup differences in the readers' estimates (R1, 6.20 ± 4.37 vs. 5.04 ± 3.47, P = 0.519; R2, 5.10 ± 4.31 vs. 4.10 ± 2.38, P = 0.970) or the readers' average values (5.65 ± 4.19 vs. 4.57 ± 2.84, P = 0.509). In comparing the tumor plane area ratio, there was no statistically significant difference between the two groups in terms of either reader's mean values (R1, 15.90 ± 9.52 vs. 19.38 ± 14.05, P = 0.525; R2, 15.32 ± 9.48 vs. 20.83 ± 12.85, P = 0.290) or the overall mean values of two readers combined (15.56 ± 9.11 vs. 20.09 ± 13.38, P = 0.388). Convenience, safety, satisfaction, and reusability were all superior in the AR localization group (P < 0.001) based on the two surgeons' responses. CONCLUSION: AR localization is an acceptable alternative to ultrasound-guided skin marking with no significant differences in surgical outcomes.


Asunto(s)
Realidad Aumentada , Neoplasias de la Mama , Mastectomía Segmentaria , Humanos , Femenino , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Persona de Mediana Edad , Mastectomía Segmentaria/métodos , Adulto , Anciano , Cuidados Preoperatorios/métodos , Estudios Prospectivos , Mamografía/métodos , Anciano de 80 o más Años , Adulto Joven , Imagen por Resonancia Magnética/métodos , Resultado del Tratamiento
2.
Small ; : e2401295, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38412421

RESUMEN

Lithium-ion capacitors (LICs) exhibit superior power density and cyclability compared to lithium-ion batteries. However, the low initial Coulombic efficiency (ICE) of amorphous carbon anodes (e.g., hard carbon (HC) and soft carbon (SC)) limits the energy density of LICs by underutilizing cathode capacity. Here, a solution-based deep prelithiation strategy for carbon anodes is applied using a contact-ion pair dominant solution, offering high energy density based on a systematic electrode balancing based on the cathode capacity increased beyond the original theoretical limit. Increasing the anode ICE to 150% over 100%, the activated carbon (AC) capacity is doubled by activating Li+ cation storage, which unleashes rocking-chair LIC operation alongside the dual-ion-storage mechanism. The increased AC capacity results in an energy density of 106.6 Wh kg-1 AC+SC , equivalent to 281% of that of LICs without prelithiation. Moreover, this process lowers the cathode-anode mass ratio, reducing the cell thickness by 67% without compromising the cell capacity. This solution-based deep chemical prelithiation promises high-energy LICs based on transition metal-free, earth-abundant active materials to meet the practical demands of power-intensive applications.

3.
Small ; : e2402213, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38881352

RESUMEN

The intrinsic reactivity of lithium (Li) toward ambient air, combined with insufficient cycling stability in conventional electrolytes, hinders the practical adoption of Li metal anodes in rechargeable batteries. Here, a bilayer interphase for Li metal is introduced to address both its susceptibility to corrosion in ambient air and its deterioration during cycling in carbonate electrolytes. Initially, the Li metal anode is coated with a conformal bottom layer of polysiloxane bearing methacrylate, followed by further grafting with poly(vinyl ethylene carbonate) (PVEC) to enhance anti-corrosion capability and electrochemical stability. In contrast to single-layer applications of polysiloxane or PVEC, the bilayer design offers a highly uniform coating that effectively resists humid air and prevents dendritic Li growth. Consequently, it demonstrates stable plating/stripping behavior with only a marginal increase in overpotential over 200 cycles in carbonate electrolytes, even after exposure to ambient air with 46% relative humidity. The design concept paves the way for scalable production of high-voltage, long-cycling Li metal batteries.

4.
Aging Ment Health ; 28(1): 121-129, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37697800

RESUMEN

OBJECTIVES: This study examines associations between living arrangements and life satisfaction and the associated effects of gender among Korean older adults during the pandemic. METHOD: Data were drawn from the 2020 National Survey of Older Koreans-a nationally representative survey. Living arrangements were categorized into four groups: living alone; living with spouse only; living with family and spouse; and living with family without spouse. Logistic regression analyses were used to examine associations between living arrangements and life satisfaction measured as a binary outcome. RESULTS: Older adults living alone were more likely to be satisfied with life compared with those who lived with a spouse only. However, living alone became nonsignificant after controlling for social contact with friends or neighbors and social participation. Interestingly, there was a significant interaction between living arrangements and gender, showing that living alone was beneficial to older women but not to men. Subsample analysis by gender confirmed that older women living alone had a greater likelihood of being satisfied with life than those living with a spouse only, whereas men living alone had lower life satisfaction. CONCLUSION: Findings suggest that living alone is not always deleterious to older adults, particularly women. During the pandemic, older Korean women living with their spouse and/or family might be less satisfied with life due to the dual burden of family care and housework, associated with traditional gendered norms and social context.


Asunto(s)
COVID-19 , Pandemias , Masculino , Humanos , Femenino , Anciano , Ambiente en el Hogar , COVID-19/epidemiología , Características de la Residencia , Satisfacción Personal , República de Corea/epidemiología
5.
Small ; 19(16): e2206238, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36617520

RESUMEN

SiOx is a promising next-generation anode material for lithium-ion batteries. However, its commercial adoption faces challenges such as low electrical conductivity, large volume expansion during cycling, and low initial Coulombic efficiency. Herein, to overcome these limitations, an eco-friendly in situ methodology for synthesizing carbon-containing mesoporous SiOx nanoparticles wrapped in another carbon layers is developed. The chemical reactions of vinyl-terminated silanes are designed to be confined inside the cationic surfactant-derived emulsion droplets. The polyvinylpyrrolidone-based chemical functionalization of organically modified SiO2 nanoparticles leads to excellent dispersion stability and allows for intact hybridization with graphene oxide sheets. The formation of a chemically reinforced heterointerface enables the spontaneous generation of mesopores inside the thermally reduced SiOx nanoparticles. The resulting mesoporous SiOx -based nanocomposite anodes exhibit superior cycling stability (≈100% after 500 cycles at 0.5 A g-1 ) and rate capability (554 mAh g-1 at 2 A g-1 ), elucidating characteristic synergetic effects in mesoporous SiOx -based nanocomposite anodes. The practical commercialization potential with a significant enhancement in initial Coulombic efficiency through a chemical prelithiation reaction is also presented. The full cell employing the prelithiated anode demonstrated more than 2 times higher Coulombic efficiency and discharge capacity compared to the full cell with a pristine anode.

6.
Eur Radiol ; 32(7): 4909-4918, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35226155

RESUMEN

OBJECTIVES: To investigate the malignancy rate of probably benign calcifications assessed by digital magnification view and imaging and clinical features associated with malignancy. METHODS: This retrospective study included consecutive women with digital magnification views assessed as probably benign for calcifications without other associated mammographic findings from March 2009 to January 2014. Initial studies rendering a probably benign assessment were analyzed, with biopsy or 4-year imaging follow-up. Fisher's exact test and univariable logistic regression were performed. Cancer yields were calculated. RESULTS: A total of 458 lesions in 422 patients were finally included. The overall cancer yield was 2.2% (10 of 458, invasive cancer [n = 4] and DCIS [n = 6]). Calcification distribution (OR = 23.80, p = .041), calcification morphology (OR = 10.84, p = .005), increased calcifications (OR = 29.40, p = .001), and having a concurrent newly diagnosed breast cancer or high-risk lesion (OR = 10.24, p = .001) were associated with malignancy. Cancer yields did not significantly differ between grouped punctate calcifications vs. calcifications with other features (1.2% [2 of 162] vs. 2.7% [8 of 296], p = .506). The cancer yield was 1.6% (7 of 437) in women without newly diagnosed breast cancer or high-risk lesions. CONCLUSION: The cancer yield of probably benign calcifications assessed by digital magnification view was below the 2% threshold for grouped punctate calcifications and for women without newly diagnosed breast cancer or high-risk lesions. Calcification distribution, morphology, increase in calcifications, and the presence of newly diagnosed breast cancer/high-risk lesion were associated with malignancy. KEY POINTS: • Among 458 probably benign calcifications assessed by digital magnification view, the overall cancer yield was 2.2% (10 of 458). • The cancer yield was below the 2% threshold for grouped punctate calcifications (1.2%, 2 of 162) and in women without newly diagnosed breast cancer or high-risk lesions (1.6%, 7 of 437). • Calcification distribution, morphology, increase in calcifications, and the presence of newly diagnosed breast cancer/high-risk lesion were associated with malignancy (all p < .05).


Asunto(s)
Neoplasias de la Mama , Calcinosis , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Calcinosis/diagnóstico por imagen , Calcinosis/patología , Femenino , Humanos , Mamografía/métodos , Estudios Retrospectivos , Riesgo
7.
J Am Chem Soc ; 143(24): 9169-9176, 2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34111352

RESUMEN

Although often overlooked in anode research, the anode's initial Coulombic efficiency (ICE) is a crucial factor dictating the energy density of a practical Li-ion battery. For next-generation anodes, a blend of graphite and Si/SiOx represents the most practical way to balance capacity and cycle life, but its low ICE limits its commercial viability. Here, we develop a chemical prelithiation method to maximize the ICE of the blend anodes using a reductive Li-arene complex solution of regulated solvation power, which enables a full cell to exhibit a near-ideal energy density. To prevent structural degradation of the blend during prelithiation, we investigate a solvation rule to direct the Li+ intercalation mechanism. Combined spectroscopy and density functional theory calculations reveal that in weakly solvating solutions, where the Li+-anion interaction is enhanced, free solvated-ion formation is inhibited during Li+ desolvation, thereby mitigating solvated-ion intercalation into graphite and allowing stable prelithiation of the blend. Given the ideal ICE of the prelithiated blend anode, a full cell exhibits an energy density of 506 Wh kg-1 (98.6% of the ideal value), with a capacity retention after 250 cycles of 87.3%. This work highlights the promise of adopting chemical prelithiation for high-capacity anodes to achieve practical high-energy batteries.

8.
Aging Ment Health ; 25(10): 1839-1847, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33131296

RESUMEN

OBJECTIVES: Our study examines the relationship between digital technology use and depressive symptoms among older Koreans and whether social interaction moderates the relationship. METHODS: The data were drawn from the 2017 Survey of Living Conditions and Welfare Needs of Korean Older Persons, a nationally representative survey. Digital technology use was measured by the number of digital functions that respondents perform with their electronic devices. Social interactions were measured by the frequencies of face-to-face and remote connections with friends or neighbors. Relationships were estimated with multiple regression analyses. RESULTS: Digital technology use was inversely associated with depressive symptoms even after adjusting for covariates including cognitive function. Both remote and face-to-face connections with friends or neighbors were associated with fewer depressive symptoms. An interaction between digital technology use and remote contact also was detected: the effect of digital technology use on depressive symptoms was more beneficial for older adults with infrequent remote contact with friends or neighbors than for those with frequent remote contact. CONCLUSION: Findings suggest that digital technology use can reduce depressive symptoms of older adults, especially those who have fewer social interactions. Educating older adults to increase their digital literacy level and use of remote interactions may improve their psychological wellbeing, perhaps even during times of a viral pandemic.


Asunto(s)
Depresión , Interacción Social , Anciano , Anciano de 80 o más Años , Depresión/epidemiología , Tecnología Digital , Amigos , Humanos , República de Corea/epidemiología
9.
J Cell Mol Med ; 24(20): 11768-11778, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32885578

RESUMEN

Atrial structural remodelling including atrial hypertrophy and fibrosis is a key mediator of atrial fibrillation (AF). We previously demonstrated that the matricellular protein CCN5 elicits anti-fibrotic and anti-hypertrophic effects in left ventricles under pressure overload. We here determined the utility of CCN5 in ameliorating adverse atrial remodelling and arrhythmias in a murine model of angiotensin II (AngII) infusion. Advanced atrial structural remodelling was induced by AngII infusion in control mice and mice overexpressing CCN5 either through transgenesis (CCN5 Tg) or AAV9-mediated gene transfer (AAV9-CCN5). The mRNA levels of pro-fibrotic and pro-inflammatory genes were markedly up-regulated by AngII infusion, which was significantly normalized by CCN5 overexpression. In vitro studies in isolated atrial fibroblasts demonstrated a marked reduction in AngII-induced fibroblast trans-differentiation in CCN5-treated atria. Moreover, while AngII increased the expression of phosphorylated CaMKII and ryanodine receptor 2 levels in HL-1 cells, these molecular features of AF were prevented by CCN5. Electrophysiological studies in ex vivo perfused hearts revealed a blunted susceptibility of the AAV9-CCN5-treated hearts to rapid atrial pacing-induced arrhythmias and concomitant reversal in AngII-induced atrial action potential prolongation. These data demonstrate the utility of a gene transfer approach targeting CCN5 for reversal of adverse atrial structural and electrophysiological remodelling.


Asunto(s)
Remodelación Atrial , Fenómenos Electrofisiológicos , Atrios Cardíacos/patología , Atrios Cardíacos/fisiopatología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Angiotensina II , Animales , Arritmias Cardíacas/complicaciones , Arritmias Cardíacas/patología , Arritmias Cardíacas/fisiopatología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Línea Celular , Transdiferenciación Celular , Dependovirus/metabolismo , Fibrosis , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Transgénicos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Miofibroblastos/metabolismo , Miofibroblastos/patología
10.
Am J Geriatr Psychiatry ; 28(7): 748-754, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31926841

RESUMEN

OBJECTIVE: We examined the role of age discrimination in suicidal ideation among community-dwelling older adults in South Korea. METHODS: We analyzed adults aged 65 or older residing in Korea drawn from the 2014 Survey of Living Conditions and Welfare Needs of Korean Older Persons (total unweighted n = 10,279; total weighted N = 6,280,588). Data were analyzed using chi-square, t tests, and logistic regression analyses. RESULTS: Results from logistic regression analysis showed that after adjusting for covariates, Korean elders who experienced age discrimination had 2.26 times higher odds of having suicidal ideation than those who did not. CONCLUSIONS: The experience of age discrimination increased the risk of suicidal ideation among Korean elders. Identifying ways to reduce age discrimination may be an effective means of reducing suicidal ideation, which would, in turn, potentially decrease suicide rates among older adults. There may be cross-cultural clinical implications and variations due to belief systems surrounding respect for older adults.


Asunto(s)
Ageísmo/estadística & datos numéricos , Asiático/psicología , Ideación Suicida , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Estudios Transversales , Femenino , Evaluación Geriátrica , Estado de Salud , Encuestas Epidemiológicas , Humanos , Vida Independiente , Modelos Logísticos , Masculino , República de Corea/epidemiología
11.
Angew Chem Int Ed Engl ; 59(34): 14473-14480, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32400120

RESUMEN

Prelithiation is of great interest to Li-ion battery manufacturers as a strategy for compensating for the loss of active Li during initial cycling of a battery, which would otherwise degrade its available energy density. Solution-based chemical prelithiation using a reductive chemical promises unparalleled reaction homogeneity and simplicity. However, the chemicals applied so far cannot dope active Li in Si-based high-capacity anodes but merely form solid-electrolyte interphases, leading to only partial mitigation of the cycle irreversibility. Herein, we show that a molecularly engineered Li-arene complex with a sufficiently low redox potential drives active Li accommodation in Si-based anodes to provide an ideal Li content in a full cell. Fine control over the prelithiation degree and spatial uniformity of active Li throughout the electrodes are achieved by managing time and temperature during immersion, promising both fidelity and low cost of the process for large-scale integration.

12.
J Mol Cell Cardiol ; 129: 58-68, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30771307

RESUMEN

The reduced expression of cardiac sarco-endoplasmic reticulum Ca2+ ATPase (SERCA2a) is a hallmark of heart failure. We previously showed that miR-25 is a crucial transcriptional regulator of SERCA2a in the heart. However, the precise mechanism of cardiac miR-25 regulation is largely unknown. Literatures suggested that miR-25 is regulated by the transcriptional co-factor, sine oculis homeobox homolog 1 (Six1), which in turn is epigenetically regulated by polycomb repressive complex 2 (PRC 2) in cardiac progenitor cells. Therefore, we aimed to investigate whether Six1 and PRC2 are indeed involved in the regulation of the miR-25 level in the setting of heart failure. Six1 was up-regulated in the failing hearts of humans and mice. Overexpression of Six1 led to adverse cardiac remodeling, whereas knock-down of Six1 attenuated pressure overload-induced cardiac dysfunction. The adverse effects of Six1 were ameliorated by knock-down of miR-25. The epigenetic repression on the Six1 promoter by PRC2 was significantly reduced in failing hearts. Epigenetic repression of Six1 is relieved through a reduction of PRC2 activity in heart failure. Six1 up-regulates miR-25, which is followed by reduction of cardiac SERCA2a expression. Collectively, these data showed that the PRC2-Six1-miR-25 signaling axis is involved in heart failure. Our finding introduces new insight into potential treatments of heart failure.


Asunto(s)
Insuficiencia Cardíaca/genética , Proteínas de Homeodominio/metabolismo , MicroARNs/metabolismo , Complejo Represivo Polycomb 2/metabolismo , Transducción de Señal , Animales , Epigénesis Genética , Técnicas de Silenciamiento del Gen , Insuficiencia Cardíaca/fisiopatología , Proteínas de Homeodominio/genética , Humanos , Ratones Endogámicos C57BL , MicroARNs/genética , Presión , Regiones Promotoras Genéticas , Regulación hacia Arriba/genética , Remodelación Ventricular/genética
13.
J Am Chem Soc ; 140(44): 14533-14537, 2018 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-30176142

RESUMEN

Conductive metal-organic frameworks (c-MOFs) have shown outstanding performance in energy storage and electrocatalysis. Varying the bridging metal species and the coordinating atom are versatile approaches to tune their intrinsic electronic properties in c-MOFs. Herein we report the first synthesis of the oxygen analog of M3(C6X6)2 (X = NH, S) family using Cu(II) and hexahydroxybenzene (HHB), namely Cu-HHB [Cu3(C6O6)2], through a kinetically controlled approach with a competing coordination reagent. We also successfully demonstrate an economical synthetic approach using tetrahydroxyquinone as the starting material. Cu-HHB was found to have a partially eclipsed packing between adjacent 2D layers and a bandgap of approximately 1 eV. The addition of Cu-HHB to the family of synthetically realized M3(C6X6)2 c-MOFs will enable greater understanding of the influence of the organic linkers and metals, and further broadens the range of applications for these materials.

14.
J Am Chem Soc ; 140(32): 10315-10323, 2018 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-30041519

RESUMEN

Redox-active organic materials have gained growing attention as electrodes of rechargeable batteries. However, their key limitations are the low electronic conductivity and limited chemical and structural stability under redox conditions. Herein, we report a new cobalt-based 2D conductive metal-organic framework (MOF), Co-HAB, having stable, accessible, dense active sites for high-power energy storage device through conjugative coordination between a redox-active linker, hexaaminobenzene (HAB), and a Co(II) center. Given the exceptional capability of Co-HAB for stabilizing reactive HAB, a reversible three-electron redox reaction per HAB was successfully demonstrated for the first time, thereby presenting a promising new electrode material for sodium-ion storage. Specifically, through synthetic tunability of Co-HAB, the bulk electrical conductivity of 1.57 S cm-1 was achieved, enabling an extremely high rate capability, delivering 214 mAh g-1 within 7 min or 152 mAh g-1 in 45 s. Meanwhile, an almost linear increase of the areal capacity upon increasing active mass loading up to 9.6 mg cm-2 was obtained, demonstrating 2.6 mAh cm-2 with a trace amount of conducting agent.

15.
Sociol Health Illn ; 39(7): 1206-1226, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28543619

RESUMEN

Socialising with higher-status individuals can be hypothesised to exert opposing influences on the mental health of the ego. On the one hand, socialising with higher-status alters might enable individuals to access valuable resources. On the other hand, status-discrepant friendships could be detrimental to mental health by engendering feelings of unfairness. We sought to examine the impact of status-discrepant social relationships on depressive symptoms in the 2012 Korean General Social Survey (KGSS), a nationally representative sample. We show that socialising with higher-status people is positively associated with depressive symptoms. There is no significant difference between those socialising with equivalent-status or with lower-status alters. Perceived unfairness also increase depressive symptoms. Respondents socialising with higher-status alters tend to report greater depressive symptoms as their perceived unfairness increases. Gender-stratified analyses reveal that the detrimental impact of status-discrepant relationships are observed for men only, not for women. These findings suggest that socialising with higher-status people can be a net detriment for mental wellbeing by increasing stress/frustration or decreasing psychological resources such as self-esteem, and that these effects are more pronounced for individuals who perceive that society is unfair. This pattern appears stronger for men, which might be associated with gender roles internalised through gender socialisation processes.


Asunto(s)
Relaciones Interpersonales , Salud Mental , Clase Social , Medio Social , Adulto , Depresión/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea , Autoimagen , Factores Sexuales , Encuestas y Cuestionarios
16.
Ecotoxicology ; 24(4): 863-72, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25724346

RESUMEN

The green alga Closterium ehrenbergii occurs in fresh water environments and has been suggested as a model for ecotoxicological assessment. Quantitative real-time PCR (qRT-PCR), with its high sensitivity and specificity, is a preferred method for reliable quantification of gene expression levels. qRT-PCR requires reference genes to normalize the transcription level of the target gene, and selection of appropriate references is crucial. Here, we evaluated nine housekeeping genes, that is, 18S rRNA, ACT, TUA, TUB, eIF, H4, UBQ, rps4, and GAPDH, using 34 RNA samples of C. ehrenbergii cultured in various environments (e.g. exposure to heat shock, UV, metals, and non-metallic chemicals). Each housekeeping gene tested displayed different ranges of C T values for each experimental condition. The gene stability was determined using the descriptive statistic software geNorm, which showed that ACT, H4, and TUA were the most suitable reference genes for all the conditions tested. In addition, at least three genes were required for proper normalization. With these references, we assessed the expression level of the heat shock protein 70 (HSP70) gene in C. ehrenbergii cells exposed to thermal and toxic contaminant stress and found that it was significantly up-regulated by these stressors. This study provides potential reference genes for gene expression studies on C. ehrenbergii with qRT-PCR.


Asunto(s)
Proteínas Algáceas/genética , Closterium/genética , Ecotoxicología/métodos , Expresión Génica , Genes Esenciales , Toxicogenética/métodos , Proteínas Algáceas/metabolismo , Closterium/metabolismo , Datos de Secuencia Molecular , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN
17.
Environ Toxicol ; 29(12): 1379-89, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23661567

RESUMEN

Diatoms are sensitive indicators of water quality, and hence used for environmental hazard assessments; however, their toxicogenomic studies have been insufficiently attempted. In the present study, we determined the cDNA sequence of heat shock protein 20 (Hsp20) gene from the diatom Ditylum brightwellii, and examined the transcriptional responses of the gene after exposing it to environmental stressors such as thermal shock, metals, and endocrine-disrupting chemicals (EDCs). The open reading frame (ORF) of DbHsp20 was 531 bp long, encoding 177 amino acid residues (19.49 kDa) with a conserved C-terminal and α-crystallin domain. The genomic region of DbHsp20 did not contain introns. Phylogeny of eukaryotic Hsp20s showed D. brightwellii was closely related to other diatoms. With regard to the gene expressional profile, real-time PCR results showed that the gene was significantly upregulated (P < 0.001) under thermal stress, with the highest change of 3.2-fold. Metals' (copper and nickel) treatments showed that it was induced after a certain point of treated concentration. On the contrary, EDCs did not display noticeable change on the expression of DbHsp20. These results suggest that the diatom Hsp20 basically responds to thermal stress, but may differentially respond to toxic substances such as metals and organic compounds such as EDCs.


Asunto(s)
Diatomeas/efectos de los fármacos , Disruptores Endocrinos/farmacología , Contaminantes Ambientales/farmacología , Proteínas del Choque Térmico HSP20/genética , Metales/farmacología , Cobre/farmacología , Diatomeas/genética , Diatomeas/metabolismo , Proteínas del Choque Térmico HSP20/clasificación , Proteínas del Choque Térmico HSP20/metabolismo , Filogenia , Transcripción Genética/efectos de los fármacos
18.
Angew Chem Int Ed Engl ; 53(25): 6364-8, 2014 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-24692071

RESUMEN

We report on the capability of polydopamine (PDA), a mimic of mussel adhesion proteins, as an electron gate as well as a versatile adhesive for mimicking natural photosynthesis. This work demonstrates that PDA accelerates the rate of photoinduced electron transfer from light-harvesting molecules through two-electron and two-proton redox-coupling mechanism. The introduction of PDA as a charge separator significantly increased the efficiency of photochemical water oxidation. Furthermore, simple incorporation of PDA ad-layer on the surface of conducting materials, such as carbon nanotubes, facilitated fast charge separation and oxygen evolution through the synergistic effect of PDA-mediated proton-coupled electron transfer and the high conductivity of the substrate. Our work shows that PDA is an excellent electron acceptor as well as a versatile adhesive; thus, PDA constitutes a new electron gate for harvesting photoinduced electrons and designing artificial photosynthetic systems.


Asunto(s)
Biomimética , Indoles/química , Fotosíntesis , Polímeros/química , Transporte de Electrón , Indoles/metabolismo , Estructura Molecular , Polímeros/metabolismo , Proteínas/química , Agua/química
19.
Soc Sci Med ; 340: 116501, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38103496

RESUMEN

RATIONALE: Despite a growing body of empirical evidence on the detrimental effects of work-family conflict (WFC) on psychological health, little attention has been given to whether educational mismatch in the workplace, which refers to the perceived level of match between one's attained education and the required educational level for a position, may exacerbate these effects. OBJECTIVE: The purpose of this study was to examine the relationship between WFC, educational mismatch, and depressive symptoms in Korean working women, with a particular focus on the potential moderating effects of educational mismatch on the association between WFC and depressive symptoms. METHODS: The data utilized for this study were collected from 5174 married working women over five waves (16,610 person-observations) of the Korean Longitudinal Survey of Women and Families spanning 8 years between 2012 and 2020. Fixed effects (FE) models were estimated to account for unobserved individual-level heterogeneity. RESULTS: FE estimates indicated that WFC is associated with an increase in depressive symptoms, even after accounting for unobserved confounding factors and time-varying covariates. The interaction model provides evidence for the moderating role of educational mismatch in the association between WFC and depressive symptoms. The positive association between WFC and depressive symptoms was more pronounced among those who perceive themselves as "overeducated." The estimated coefficient for the association was about 45% larger for those who perceive themselves as "overeducated" than their "well-matched" counterparts. CONCLUSION: The study's findings suggest a robust link between WFC and depressive symptoms and further elaborate on how this association varies depending on educational mismatch. In Korea, where conservative gender role norms of female-caregiver ideology are still prevalent, WFC and educational mismatch can act as double jeopardy, exacerbating the mental health of working women.


Asunto(s)
Conflicto Familiar , Mujeres Trabajadoras , Humanos , Femenino , Conflicto Familiar/psicología , Depresión/epidemiología , Depresión/etiología , Depresión/psicología , Encuestas y Cuestionarios , Estrés Psicológico/psicología , Escolaridad , República de Corea/epidemiología
20.
ACS Biomater Sci Eng ; 10(1): 575-587, 2024 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-38150627

RESUMEN

Glioblastoma (GBM) is the deadliest tumor of the central nervous system, with a median survival of less than 15 months. Despite many trials, immune checkpoint-blocking (ICB) therapies using monoclonal antibodies against the PD-1/PD-L1 axis have demonstrated only limited benefits for GBM patients. Currently, the main hurdles in brain tumor therapy include limited drug delivery across the blood-brain barrier (BBB) and the profoundly immune-suppressive microenvironment of GBM. Thus, there is an urgent need for new therapeutics that can cross the BBB and target brain tumors to modulate the immune microenvironment. To this end, we developed an ICB strategy based on the BBB-permeable, 24-subunit human ferritin heavy chain, modifying the ferritin surface with 24 copies of PD-L1-blocking peptides to create ferritin-based ICB nanocages. The PD-L1pep ferritin nanocages first demonstrated their tumor-targeting and antitumor activities in an allograft colon cancer model. Next, we found that these PD-L1pep ferritin nanocages efficiently penetrated the BBB and targeted brain tumors through specific interactions with PD-L1, significantly inhibiting tumor growth in an orthotopic intracranial tumor model. The addition of PD-L1pep ferritin nanocages to triple in vitro cocultures of T cells, GBM cells, and glial cells significantly inhibited PD-1/PD-L1 interactions and restored T-cell activity. Collectively, these findings indicate that ferritin nanocages displaying PD-L1-blocking peptides can overcome the primary hurdle of brain tumor therapy and are, therefore, promising candidates for treating GBM.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Antígeno B7-H1/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Ferritinas/uso terapéutico , Péptidos/uso terapéutico , Microambiente Tumoral
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