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1.
Nature ; 592(7854): 381-385, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33820983

RESUMO

Metal halide perovskites of the general formula ABX3-where A is a monovalent cation such as caesium, methylammonium or formamidinium; B is divalent lead, tin or germanium; and X is a halide anion-have shown great potential as light harvesters for thin-film photovoltaics1-5. Among a large number of compositions investigated, the cubic α-phase of formamidinium lead triiodide (FAPbI3) has emerged as the most promising semiconductor for highly efficient and stable perovskite solar cells6-9, and maximizing the performance of this material in such devices is of vital importance for the perovskite research community. Here we introduce an anion engineering concept that uses the pseudo-halide anion formate (HCOO-) to suppress anion-vacancy defects that are present at grain boundaries and at the surface of the perovskite films and to augment the crystallinity of the films. The resulting solar cell devices attain a power conversion efficiency of 25.6 per cent (certified 25.2 per cent), have long-term operational stability (450 hours) and show intense electroluminescence with external quantum efficiencies of more than 10 per cent. Our findings provide a direct route to eliminate the most abundant and deleterious lattice defects present in metal halide perovskites, providing a facile access to solution-processable films with improved optoelectronic performance.

2.
Ethn Health ; 29(2): 179-198, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37970802

RESUMO

INTRODUCTION: Approximately 42.5% of adults aged 18-59 in the United States is estimated to be affected by human papillomavirus (HPV) infection. However, Asian Americans have the lowest HPV vaccination initiation rate compared to other racial groups. This study aims to explore the experiences of HPV and the HPV vaccination among ethnic Korean women and men in the United States. METHODS: A total of 33 ethnic Korean and Korean Americans aged 27-45 years living in the U.S. were recruited via word-of-mouth and social media using a purposive sampling strategy. They participated in an online survey. Of the 33 participants, 29 (14 females and 15 males) participated in in-depth interviews via password-protected Zoom. A content analysis approach was used to analyze the interviews. RESULTS: Only 32% of participants had received the HPV vaccine at least once (female: 35.3%, male: 12.5%). Six major themes emerged from data analysis: (1) awareness of HPV, HPV vaccine, and HPV-associated cancers; (2) attitudes toward the HPV vaccine; (3) barriers to HPV vaccination; (4) women's experiences and preferences for pap smear testing; (5) experiences with HPV diagnosis; and (6) HPV and HPV vaccination education preferences. CONCLUSION: The findings highlight cultural factors that may impede the discussion about and uptake of HPV vaccination and HPV-associated cancer screening, which emphasize the need for culturally appropriate interventions to overcome stigma around HPV and enhance vaccination rates. Healthcare providers should consider ethnic and cross-cultural differences perceptions to effectively HPV-related health information. This study provides insight into the experiences and understanding of HPV and vaccination among ethnic Korean men and women, laying the groundwork for developing culturally-tailored programs that sim to increase HPV vaccination rates and mitigate the stigma and impact of HPV-related disease in this community.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Adulto , Humanos , Feminino , Masculino , Estados Unidos , Infecções por Papillomavirus/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Vacinação , República da Coreia , Aceitação pelo Paciente de Cuidados de Saúde
3.
Comput Inform Nurs ; 42(2): 136-143, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38129323

RESUMO

Mobile healthcare has emerged as a prominent technological solution for self-management of health. However, the development and utilization of tailored mobile healthcare applications for older adults with diabetes mellitus remain limited. This study examined the relationship between social support and mobile healthcare use and further explored how this relationship varies with eHealth literacy and application design among older adults with diabetes mellitus. A descriptive cross-sectional trial was conducted with a structured self-report questionnaire, surveying 252 South Korean older adults with diabetes mellitus via offline and online modes. The mediating effect and moderated mediating effect were analyzed with the PROCESS macro of SPSS. eHealth literacy mediated the relationship between social support and mobile healthcare use. High levels of eHealth literacy and social support may increase mobile healthcare use among older adults with diabetes. Application design aesthetics facilitated mobile healthcare use. Future researchers, healthcare providers, and developers can contribute to the development of tailored mobile healthcare applications for older adults with diabetes mellitus by considering application design aspects such as font size, color, and menu configuration.


Assuntos
Diabetes Mellitus , Letramento em Saúde , Aplicativos Móveis , Telemedicina , Humanos , Idoso , Estudos Transversais , Diabetes Mellitus/terapia , Apoio Social
4.
Int J Mol Sci ; 24(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38069356

RESUMO

Forsythiaside A (FA) is an active constituent isolated from Forsythia suspensa, a beneficial herb used in traditional medicine known for its antioxidant and anti-inflammatory properties. Although various studies have suggested that FA has the protective effects, its impacts on arachidonic acid (AA) plus iron in vitro models and carbon tetrachloride (CCl4)-induced mouse liver damage in vivo have not been explored. In this study, HepG2 cells were subjected to AA + iron treatment to induce apoptosis and mitochondrial impairment and determine the molecular mechanisms. FA exhibited protective effects by inhibiting cell damage and reactive oxygen species (ROS) production induced by AA + iron, as assessed via immunoblot and flow cytometry analyses. Further molecular investigations revealed that FA resulted in the activation of extracellular-signal-related protein kinase (ERK), which subsequently triggered the activation of AMP-activated protein kinase (AMPK), a critical regulator of cellular oxidative stress. Additionally, FA modulated the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway, which is a significant antioxidant transcription factor regulated by the AMPK pathway. For in vivo studies, mice were orally administered FA and then subjected to induction of CCl4-based hepatotoxicity. The protective effect of FA was confirmed via blood biochemistry and immunohistochemical analyses. In conclusion, our findings demonstrated the protective effects of FA against oxidative stress both in vitro and in vivo, thus indicating that FA is a potential candidate for liver protection. Our study sheds light on the mechanistic pathways involved in the antioxidant effects of FA, highlighting the hepatoprotective potential of naturally occurring compounds in traditional herbs, such as FA.


Assuntos
Proteínas Quinases Ativadas por AMP , Antioxidantes , Animais , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Transdução de Sinais , Espécies Reativas de Oxigênio/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Ferro/farmacologia
5.
Molecules ; 28(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37513335

RESUMO

This study evaluated the effects of Rorippa cantoniensis (Lour.) ohwi extract (RCE) on factors associated with inflammation-related skin lesions in RAW 264.7 and HaCaT cells. RCE inhibited the levels of proinflammatory mediators and cytokines such as nitric oxide (NO), prostaglandin E2 (PGE2), interleukin (IL)-6, and tumor necrosis factor (TNF)-α in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. In addition, RCE significantly inhibited the expression of chemokines and cytokines such as MDC/CCL22, TARC/CCL17, RANTES/CCL5, CTSS, IL-6, IL-1ß, and TNF-α in HaCaT cells costimulated by TNF-α and interferon (IFN)-γ in a concentration-dependent manner. These results suggest that RCE attenuated the TNF-α- and IFN-γ-induced release of proinflammatory chemokines and cytokines probably by suppressing the activation of MAPK (JNK and p38), NF-κB, and STAT1 signaling. Moreover, RCE significantly increased the expression of skin components such as hyaluronic acid and aquaporin, which play important roles in the physical and chemical barriers of the skin. These results suggest that RCE has significant anti-inflammatory and antiatopic activities, which may be beneficial for the topical treatment of inflammatory skin disorders.


Assuntos
Células HaCaT , Rorippa , Animais , Camundongos , Humanos , Rorippa/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Queratinócitos , Linhagem Celular , Citocinas/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , NF-kappa B/metabolismo , Quimiocinas/metabolismo , Células RAW 264.7
6.
Health Care Women Int ; : 1-17, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36943248

RESUMO

In this study, we described perinatal women's experiences of childbirth and parenting during the COVID-19 pandemic, guided by the qualitative descriptive methodology. We interviewed 14 women who gave birth during the pandemic. Data were analyzed using inductive qualitative content analysis. Our results showed that perinatal women experienced fear of COVID-19 infection, depression, and difficulties related to childbirth and parenting. They believed that online services and sharing information through social networking were helpful. They were looking forward to participating in outdoor activities to promote children's development and suggested enforcing untact (no contact) services for perinatal women in the post-COVID-19 era.

7.
Policy Polit Nurs Pract ; 24(2): 81-90, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36482714

RESUMO

Uptake of the COVID-19 vaccine by nurses lags behind that of other health care professionals with minimal empirical evidence to understand this phenomenon. In this secondary analysis, we examined nurses' individual and work-related characteristics and their association with COVID-19 vaccination status. Alumni of three Ohio nursing colleges and members of a professional organization were invited to complete questionnaires from June through August 2021. Logistic regression models were used to evaluate associations between nurse characteristics and vaccination status. Among 844 respondents, 754 (80.30%) had received at least one dose of the vaccine. Older age, having a bachelor's degree or higher, and working in critical care were associated with vaccination. Providing direct care for COVID-19 patients in the last 7 days and a higher perception of one's work being affected by COVID-19 were significantly associated with being vaccinated, whereas prior COVID-19 infection was inversely associated with vaccination status. Our findings suggest that COVID-19 vaccine uptake among nurses is influenced by a host of factors related to virus knowledge, beliefs, and risk perceptions. Awareness of these factors can aid the development of interventions to increase nurses' acceptance of vaccines.


Assuntos
COVID-19 , Enfermeiras e Enfermeiros , Humanos , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Ohio , Vacinação
8.
Small ; 18(42): e2203633, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36108130

RESUMO

Herein, a sequential gas-phase process involving air jet milling followed by chemical vapor deposition (CVD), is demonstrated to be an efficient strategy for the fabrication of heterolayered 2D nanohybrids (2DNHs) decorated with nanocatalysts. Tens of grams of the nanohybrids, which is a substantial quantity at the laboratory scale, are produced in the absence of solvents and water, and without the need for an extra purification procedure. Air jet milling enables the development of binary/ternary heterolayered structures consisting of graphene, WSe2 , and/or MoS2 via the gas-phase co-exfoliation of their bulk counterparts. Based on the X-ray photoelectron and Raman spectroscopy data, the heterolayers of the 2DNHs exert chemical and electronic effects on each other, while diminishing the interactions between same-component layers. Moreover, the electrochemically active surface area increases by >190% and the charge transfer resistance decreases by >35%. CVD is performed to introduce Pt and Ru nanoparticles with diameters of a few nanometers as additional electrocatalysts into the 2DNHs. The nanocatalyst-decorated 2DNHs show excellent performance for the production of hydrogen and oxygen gases in water-splitting cells. Notably, the proposed all-gas-phase processes allow for the large-scale production of functional 2DNHs with minimal negative environmental impact, which is crucial for the commercialization of nanomaterials.


Assuntos
Doenças Cardiovasculares , Grafite , Humanos , Água , Grafite/química , Molibdênio , Hidrogênio , Gases , Oxigênio/química , Solventes
9.
J Nurs Adm ; 52(7-8): 392-398, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35815868

RESUMO

OBJECTIVE: The aim of this study was to determine relationships between moral injury (MI), well-being, and resilience among staff nurses and nurse leaders practicing during the COVID-19 (coronavirus disease 2019) pandemic. BACKGROUND: Attention to MI among health professionals, including nurses, increased in 2021, particularly related to the pandemic. Few studies examined MI, well-being, and resilience; even fewer provided implications for leadership/management. METHODS: The sample included 676 RNs practicing in Ohio. The electronic survey included assessments of MI, well-being, and resilience distributed via the Ohio Nurses Association and the schools of nursing alumni Listservs. RESULTS: There was a significant association between MI and negative well-being and negative association between MI and resilience. Differences were observed between staff nurses and leaders. CONCLUSIONS: This is the first study relating MI, resilience, and well-bring among nurses and nurse leaders during the pandemic. There is a need for additional research to further our understanding about nurses' health and well-being during the pandemic and beyond.


Assuntos
COVID-19 , Enfermeiras e Enfermeiros , Transtornos de Estresse Pós-Traumáticos , Humanos , Liderança , Pandemias , Inquéritos e Questionários
10.
Small ; 17(41): e2102892, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34515417

RESUMO

Native extracellular matrix (ECM) exhibits dynamic change in the ligand position. Herein, the ECM-emulating control and real-time monitoring of stem cell differentiation are demonstrated by ligand nanoassembly. The density of gold nanoassembly presenting cell-adhesive Arg-Gly-Asp (RGD) ligand on Fe3 O4 (magnetite) nanoparticle in nanostructures flexibly grafted to material is changed while keeping macroscale ligand density invariant. The ligand nanoassembly on the Fe3 O4 can be magnetically attracted to mediate rising and falling ligand movements via linker stretching and compression, respectively. High ligand nanoassembly density stimulates integrin ligation to activate the mechanosensing-assisted stem cell differentiation, which is monitored via in situ real-time electrochemical sensing. Magnetic control of rising and falling ligand movements hinders and promotes the adhesion-mediated mechanotransduction and differentiation of stem cells, respectively. These rising and falling ligand states yield the difference in the farthest distance (≈34.6 nm) of the RGD from material surface, thereby dynamically mimicking static long and short flexible linkers, which hinder and promote cell adhesion, respectively. Design of cytocompatible ligand nanoassemblies can be made with combinations of dimensions, shapes, and biomimetic ligands for remotely regulating stem cells for offering novel methodologies to advance regenerative therapies.


Assuntos
Fenômenos Magnéticos , Mecanotransdução Celular , Adesão Celular , Diferenciação Celular , Ligantes
11.
Ethn Health ; 26(3): 379-391, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-30141338

RESUMO

Cervical cancer is caused by human papillomavirus (HPV) infection, which can be prevented by vaccination. Mothers play an important role in promoting vaccination and health education. However, Cambodian American mothers reported to have challenges to play a role as primary health educators due to lack of health knowledge and language and cultural gaps. Therefore, this study aims to understand the Cambodian American daughters' and mothers' awareness, knowledge and social norms of HPV vaccination and their health communication and vaccination decision-making.We conducted a pilot randomized clinical trial to promote HPV vaccination. In this study, we have only reported findings from baseline data examining individual, interpersonal and social determinants of HPV vaccination behavior among 19 dyads of Cambodian American mothers and daughters.Both mothers and daughters demonstrated low levels of awareness and knowledge. A significant relationship was found between the daughters' HPV vaccine decisions and their perception of their mothers' intention on HPV vaccination for them.Culturally and linguistically appropriate communication strategies such as storytelling or visual presentation approaches may be more effective than the current practice of using information-based written materials to promote HPV vaccination and health education among Cambodian Americans.


Assuntos
Comunicação em Saúde , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Intenção , Mães , Infecções por Papillomavirus/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde , Normas Sociais , Neoplasias do Colo do Útero/prevenção & controle , Vacinação
12.
Public Health Nurs ; 38(3): 396-405, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33569854

RESUMO

BACKGROUND: The HPV vaccination is effective and safe for preventing HPV infection and HPV attributable cancers. Despite this fact, the uptake rate of the vaccination in the United States has remained below the national target of 80%. Health policy focused on allocating resources and creating vaccine-promoting environments can influence HPV vaccination coverage rates. There is a scarcity of information about the HPV vaccination-related health policy and its impact on the outcome of vaccine uptake. METHOD: We conducted a comprehensive review of HPV vaccination-related health policies at the federal, state, and professional organization levels and examined their impact on population health by reviewing national data on HPV vaccination uptake rates. RESULTS: The review revealed that (a) HPV vaccination recommendations, which serve as the federal-level HPV vaccination policy, have changed frequently in terms of gender, age criteria, and dosing schedule, and (b) the frequent changes of the policy have resulted in low uptake rates among male and young adult populations. DISCUSSION: The uptake rate should be continuously followed to evaluate the impact of recent changes to the federal-level HPV vaccination policy. State-level policies and healthcare professionals, including nurses, are important to the promotion of HPV vaccinations and decreasing HPV vaccination disparities.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Política de Saúde , Humanos , Masculino , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Estados Unidos , Vacinação , Adulto Jovem
13.
Medicina (Kaunas) ; 57(7)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34357001

RESUMO

Background and Objectives: Nontuberculous mycobacteria (NTM) infections are increasing worldwide. We evaluated the annual trends of NTM isolation on acid-fast bacillus (AFB) culture, compared to that of Mycobacterium tuberculosis, and the distribution of NTM species nationwide in South Korea. Materials and Methods: The study was conducted in a diagnostic center that is a major referral laboratory for the diagnosis of tuberculosis and NTM in South Korea. All laboratory results of AFB culture from January 2014 to December 2019 were collected. All NTM identified were definitively identified to the species level. Results: A total of 345,871 tests were performed for the diagnosis of mycobacteria. The isolation rate of NTM and M. tuberculosis was 3.7% (12,969 cases) and 4.4% (15,081 cases), respectively. The annual isolation rate of NTM increased gradually from 2.7% in 2014 to 4.8% in 2019, whereas that of M. tuberculosis decreased from 6.2% to 3.3%. There were 4988 cases of NTM identified to the species level. M. avium complex (MAC) was the most common species isolated from pulmonary sites (59.8%), followed by M. gordonae (9.2%), M. abscessus (7.0%), and M. fortuitum (5.5%). Extrapulmonary NTM were identified in 29 cases (0.6%). MAC was also the most common NTM species isolated from extrapulmonary sites (65.5%), followed by M. kansasii (10.3%), M. abscessus (6.9%), and M. fortuitum (6.9%). Conclusions: The annual isolation rate of NTM has increased gradually, whereas that of M. tuberculosis has decreased. Follow-up studies of the increases in NTM identification and NTM infections in South Korea are needed.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Micobactérias não Tuberculosas , Humanos , Laboratórios , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Encaminhamento e Consulta , República da Coreia/epidemiologia
14.
Health Educ Res ; 34(5): 483-494, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31298268

RESUMO

Although Korean American women have a higher risk of developing cervical cancer, currently there are limited culturally relevant intervention strategies for improving primary prevention of cervical cancer by promoting HPV vaccination in this population. This study reports the development of a cross-cultural, cross-generational storytelling HPV intervention using a peer-paired method, in which two storytellers interactively share their stories, as a particular innovation that might resonate with Korean American young women. The acceptability of the intervention was assessed by self-reported satisfaction and endorsement with the intervention in a pilot randomized control trial (RCT). We compared participants' responses to the intervention by their generation and cultural identity. One hundred and four Korean college women between the ages of 18-26 were recruited from the Northeastern US Participants randomized to the intervention group received a storytelling video (n = 54); the comparison group received written information (n = 50). The acceptability of the intervention was measured immediately post-intervention. The intervention group had significantly greater satisfaction than the comparison group (P < 0.05). Participants reported greater endorsement for videos that reflected their cultural and generational experiences. Future study is needed to examine the impact of such interventions on objective follow-up on HPV vaccination in a large-scale RCT.


Assuntos
Asiático/educação , Competência Cultural , Narração , Infecções por Papillomavirus/prevenção & controle , Grupo Associado , Adolescente , Adulto , Feminino , Humanos , Infecções por Papillomavirus/etnologia , República da Coreia/etnologia , Estados Unidos/epidemiologia , Universidades , Neoplasias do Colo do Útero/prevenção & controle , Adulto Jovem
15.
J Community Health ; 44(4): 646-655, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30863974

RESUMO

Human papillomavirus (HPV) is the most prevalent sexually transmitted infection that leads to nearly all cervical cancers in the United States (U.S.), which could be prevented with the HPV vaccine. Korean American women experience a high burden of cervical cancer, but little is known about their awareness, knowledge, attitudes, sociocultural factors and social network/support related to intention to obtain the HPV vaccine. This study reports baseline characteristics of 104 Korean American college women aged 18-26 and who have not been previously vaccinated against HPV, as part of a pilot randomized controlled trial testing feasibility, acceptability, and preliminary effectiveness of an HPV storytelling intervention. Data were analyzed including descriptive statistics, bivariate analysis, and multivariate logistic regression. Multivariate logistic regression was performed to understand the relationship between independent predictors of intention to receive HPV vaccination. Overall, 34.6% of participants intended to obtain the vaccine. Positive predictors of intention to receive HPV vaccine were: years in the U.S., academic major, awareness of HPV and HPV vaccine, knowledge, and HPV recommendation by healthcare provider and parents. The multivariate logistic model showed that intention to receive the HPV vaccine was significantly associated with HPV vaccine recommendation by parents (OR 4.58, 95% CI 1.37-15.36) and knowledge (OR 1.11, 95% CI 1.11-1.22). These findings suggest a need for development of interventions that are not only culturally tailored but also acculturation-sensitive to promote HPV vaccination among Korean American college women. This may play a significant role in cervical cancer prevention among Korean American college women.


Assuntos
Asiático , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Vacinas contra Papillomavirus , Adolescente , Adulto , Asiático/psicologia , Asiático/estatística & dados numéricos , Feminino , Humanos , República da Coreia/etnologia , Apoio Social , Estudantes , Estados Unidos , Universidades , Adulto Jovem
16.
Appl Environ Microbiol ; 84(22)2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30217844

RESUMO

When phages infect bacteria cultured in the presence of sublethal doses of antibiotics, the sizes of the phage plaques are significantly increased. This phenomenon is known as phage-antibiotic synergy (PAS). In this study, the observation of PAS was extended to a wide variety of bacterium-phage pairs using different classes of antibiotics. PAS was shown in both Gram-positive and Gram-negative bacteria. Cells stressed with ß-lactam antibiotics filamented or swelled extensively, resulting in an increase in phage production. PAS was also sometimes observed in the presence of other classes of antibiotics with or without bacterial filamentation. The addition of antibiotics induced recA expression in various bacteria, but a recA deletion mutant strain of Escherichia coli also showed filamentation and PAS in the presence of quinolone antibiotics. The phage adsorption efficiency did not change in the presence of the antibiotics when the cell surfaces were enlarged as they filamented. Increases in the production of phage DNA and mRNAs encoding phage proteins were observed in these cells, with only a limited increase in protein production. The data suggest that PAS is the product of a prolonged period of particle assembly due to delayed lysis. The increase in the cell surface area far exceeded the increase in phage holin production in the filamented host cells, leading to a relatively limited availability of intracellular holins for aggregating and forming holes in the host membrane. Reactive oxygen species (ROS) stress also led to an increased production of phages, while heat stress resulted in only a limited increase in phage production.IMPORTANCE Phage-antibiotic synergy (PAS) has been reported for a decade, but the underlying mechanism has never been vigorously investigated. This study shows the presence of PAS from a variety of phage-bacterium-antibiotic pairings. We show that increased phage production resulted directly from a lysis delay caused by the relative shortage of holin in filamented bacterial hosts in the presence of sublethal concentrations of stress-inducing substances, such as antibiotics and reactive oxygen species (ROS).


Assuntos
Antibacterianos/farmacologia , Bacteriófagos/efeitos dos fármacos , Bacteriófagos/fisiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Bacteriófagos/genética , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Negativas/virologia , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/metabolismo , Bactérias Gram-Positivas/virologia , Quinolonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo
17.
Nano Lett ; 17(10): 6385-6390, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-28895740

RESUMO

Edged-selectively fluorine (F) functionalized graphene nanoplatelets (EFGnPs-F) with a p-i-n structure of perovskite solar cells achieved 82% stability relative to initial performance over 30 days of air exposure without encapsulation. The enhanced stability stems from F-substitution on EFGnPs; fluorocarbons such as polytetrafluoroethylene are well-known for their superhydrophobic properties and being impervious to chemical degradation. These hydrophobic moieties tightly protect perovskite layers from air degradation. To directly compare the effect of similar hydrophilic graphene layers, edge-selectively hydrogen functionalized graphene nanoplatelet (EFGnPs-H) treated devices were tested under the same conditions. Like the pristine MAPbI3 perovskite devices, EFGnPs-H treated devices were completely degraded after 10 days. The hydrophobic properties of EFGnPs-F were characterized by contact angle measurement. The test results showed great water repellency compared to pristine perovskite films or EFGnPs-H coated films. This resulted in highly air-stable p-i-n perovskite solar cells.

18.
Appl Nurs Res ; 40: 51-60, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29579499

RESUMO

PURPOSE: To develop a theory-guided culturally grounded narrative intervention to promote HPV vaccination behavior and examine the feasibility, acceptability, and preliminary effectiveness of the intervention among dyads of Cambodian American mothers and daughters. METHOD: The principles of community-based participatory research guided the development and evaluation and involved two phases: Phase 1: Development of storytelling narrative intervention videos which focused on a series of HPV vaccination-related messages and which integrated the narrative theory with the revised network episode model (rNEM); Phase 2: conducting the pilot RCT with 19 dyads of Khmer mothers and daughters aged from 14 to 17years to examine the feasibility and acceptability of the study. FINDINGS: Recruitment was completed in 7months with an overall retention of 84%. The acceptability of the intervention was high, as reflected by the number of positive comments on the narrative video. Preliminary data indicate that vaccine uptake at one-month follow-up was the same (2 vs. 2) between intervention and control groups. However, daughters in the narrative intervention group reported higher intention to receive HPV vaccination within one month compared to the control group (4 vs. 1). CONCLUSION: All the procedures to inform a full RCT were examined, including identification of eligible participants, recruitment, randomization, intervention adherence, and short-term follow-up. The positive preliminary outcomes and feedback support the feasibility and potential effectiveness of the theory-guided narrative intervention.


Assuntos
Asiático/psicologia , Mães/psicologia , Núcleo Familiar/psicologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Adolescente , Adulto , Camboja , Feminino , Humanos , Infecções por Papillomavirus/etnologia , Projetos Piloto , Inquéritos e Questionários , Estados Unidos/etnologia
20.
Biom J ; 59(3): 405-419, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28160312

RESUMO

When analyzing time-to-event cohort data, two different ways of choosing a time scale have been discussed in the literature: time-on-study or age at onset of disease. One advantage of choosing the latter is interpretability of the hazard ratio as a function of age. To handle the analysis of age at onset in a principled manner, we present an analysis of the Cox Proportional Hazards model with time-varying coefficient for left-truncated and right-censored data. In the analysis of Northern Manhattan Study (NOMAS) with age at onset of stroke as outcome, we demonstrate that well-established risk factors may be important only around a certain age span and less established risk factors can have a strong effect in a certain age span.


Assuntos
Biometria/métodos , Modelos de Riscos Proporcionais , Fatores Etários , Estudos de Coortes , Humanos , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Análise de Sobrevida , Fatores de Tempo
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