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1.
Child Abuse Negl ; : 106863, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38816302

RESUMO

BACKGROUND: Child maltreatment is a pressing public health concern that poses long-lasting health and economic impacts on children and society. While several preventive interventions have demonstrated their effectiveness in reducing the occurrence of child maltreatment and its associated economic impacts, the cost-effectiveness of such interventions remains unclear. OBJECTIVE: This study aims to provide a comprehensive overview and a narrative synthesis of the available economic evidence on child maltreatment preventive interventions in both high-income and low-middle-income countries. METHOD: Systematic searches were conducted in MEDLINE, PsycINFO, Embase, CINAHL, Web of Science, and Econlit to identify full economic evaluations and return-on-investment studies on child maltreatment preventive interventions. The methodological quality of eligible studies was assessed using Drummond's 10-point checklist. This review adhered to the PRISMA guidelines, and summarized findings in a narrative synthesis. RESULTS: Twenty-six studies met the inclusion criteria. Of these, eight evaluated home visiting, four evaluated early childhood education (ECE), four assessed multi-component (MC), and three examined group-based parent education (GPE) interventions. The remaining studies assessed interventions to prevent abusive head trauma (AHT; n = 2), child sexual abuse (n = 2), physical abuse at school (n = 1), as well as individualized intensive parenting (IIP; n = 2), and counseling (n = 1) interventions. Two studies were conducted in low-middle-income countries, while the others were all in high-income countries. CONCLUSIONS: The included studies generally exhibited high methodological quality. Only AHT, ECE, IIP, and MC interventions demonstrated promising cost-effectiveness credentials in preventing child maltreatment. More economic evaluations are needed for interventions with mixed findings (e.g. GPE) and in low-middle-income countries.

2.
JACC Case Rep ; 29(3): 102180, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38361569

RESUMO

Prosthetic mechanical valve thrombosis has traditionally been managed with urgent surgical intervention. However, the risk of redo sternotomy can be prohibitively high in some patients. Thrombolytic therapy as a noninvasive treatment of mechanical valve thrombosis is a well-recognized alternative, but optimal dosing and patient selection remain incompletely characterized for right-side mechanical valves.

3.
J Soc Work End Life Palliat Care ; 20(2): 147-160, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38346173

RESUMO

The need for psychosocial care among patients with serious illnesses and available social work services continues to be great, especially in low- and middle-income countries. To evaluate the specific needs of Vietnamese cancer patients' quality of life (QOL), prevalence and severity of symptoms including depression and anxiety, and caregiver burden were assessed. Data on QOL, mood, caregiver burden, and other parameters were collected through face-to-face and phone- interviews. The QOL assessed by European Quality of Life scale version 5D (EQ5D) was poor but consistent with other studies of cancer patients. Assessed by the Hospital Anxiety and depression Scale (HADS), borderline or severe anxiety and depression were prevalent. Caregiver burden was high for one third of study participants. These results confirm the need among cancer patients for psycho-social support services that currently are rarely available in Vietnam. In light of this need, a comprehensive palliative care (CPC) service, including social work, was created to improve the quality of life (QOL) of Vietnamese cancer patients.


Assuntos
Ansiedade , Cuidadores , Depressão , Neoplasias , Cuidados Paliativos , Qualidade de Vida , Serviço Social , Humanos , Cuidados Paliativos/psicologia , Cuidados Paliativos/organização & administração , Vietnã , Neoplasias/psicologia , Neoplasias/terapia , Serviço Social/organização & administração , Masculino , Qualidade de Vida/psicologia , Pessoa de Meia-Idade , Feminino , Depressão/psicologia , Depressão/epidemiologia , Idoso , Cuidadores/psicologia , Ansiedade/psicologia , Ansiedade/epidemiologia , Adulto , Apoio Social , Sobrecarga do Cuidador/psicologia
4.
ACS Omega ; 8(45): 42177-42185, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024691

RESUMO

The antimicrobial activity of silver nanoparticles is widely known. However, their application to biodegradable polymeric materials is still limited. In this work, we report a strategy involving the green synthesis of nanocomposite films based on a natural biodegradable matrix. Nanometer-sized silver nanoparticles (C-AgNPs) were synthesized with the aid of ultrasound waves between the silver nitrate solution and the nanocurcumin solution. The green synthesized C-AgNPs were found to have particle sizes in the range of 5-25 nm and demonstrated good antimicrobial activity against Clostridium perfringens, Staphylococcus aureus, Bacillus subtilis, Macrophoma theicola, and Aspergillus flavus. Owing to their physical-chemical and mechanical properties and the excellent antimicrobial activities, the obtained AgNPs were used together with chitosan, cassava starch, and poly(vinyl alcohol) (PVA) to make nanocomposite films, which are suitable for the packaging requirements of various key agricultural and food products such as coffee beans, bamboo straws, and fruits. The nanocomposite films lost up to 85% of their weight after being buried in the soil for 120 days. This indicates that the films made with natural biodegradable materials are environmentally friendly.

5.
Healthcare (Basel) ; 11(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37761718

RESUMO

(1) Background: Routine episiotomy is not recommended by international guidelines; however, it occurs at a high rate in Vietnam. (2) Methods: A process to reduce unnecessary episiotomies was developed and implemented as part of the Centers of Excellence for Breastfeeding initiative, which aims to deliver high-quality breastfeeding and early essential newborn care services within a supportive policy environment. The aim of this project report is to outline the steps undertaken to reduce episiotomies, the experience in pilot hospitals, and the process towards changing policy. (3) Results: During the 14 months following the change in episiotomy policy, pilot hospital records showed no infant death or injury. Monthly monitoring data from four pilot hospitals showed that the prevalence of episiotomy was substantially lower than the average in national hospitals in Vietnam. Facilitators to reducing the episiotomy rate include the incentive of Centers of Excellence for Breastfeeding designation and supportive hospital leadership. Challenges include the ambiguity of Vietnam's national guideline on episiotomy and lack of routine monitoring on the episiotomy rate and indications. (4) Discussion: Our experience suggests that through training and routine monitoring hospitals can apply a policy of selective episiotomy and reduce the practice, particularly among multiparous women, and improve breastfeeding rates.(5) Conclusions: Sharing our experience of implementing this process and offering four areas for action will hopefully contribute to expanded use of mother-friendly, evidence-based care as policy and routine practice in Vietnam and similar settings.

6.
Commun Biol ; 6(1): 223, 2023 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-36841892

RESUMO

Bioactive small-molecule inhibitors represent a treasure chest for future drugs. In vitro high-throughput screening is a common approach to identify the small-molecule inhibitors that bind tightly to purified targets. Here, we investigate the inhibitor-target binding/unbinding kinetics in E. coli cells using a benzimidazole-derivative DNA inhibitor as a model system. We find that its unbinding rate is not constant but depends on cell growth rate. This dependence is mediated by the cellular activity, forming a feedback loop with the inhibitor's activity. In accordance with this feedback, we find cell-to-cell heterogeneity in inhibitor-target interaction, leading to co-existence of two distinct subpopulations: actively growing cells that dissociate the inhibitors from the targets and non-growing cells that do not. We find similar heterogeneity for other clinical DNA inhibitors. Our studies reveal a mechanism that couples inhibitor-target kinetics to cell physiology and demonstrate the significant effect of this coupling on drug efficacy.


Assuntos
DNA , Escherichia coli , Escherichia coli/metabolismo , Cinética , DNA/metabolismo
7.
PLoS One ; 17(12): e0279446, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36548356

RESUMO

BACKGROUND: The COVID-19 pandemic and governments' response lead to dramatical change in quality of life worldwide. However, the extent of this change in Vietnamese medical and nursing students has not been documented. OBJECTIVES: The study aims to describe the quality of life and changes in quality of life of medical and nursing students during the COVID-19 pandemic and examine the association of quality of life and changes in quality of life with fear of COVID-19 and other socio-economic and demographic factors. METHODS: The study was a cross-sectional study on all students of Hanoi Medical University from 3 majors: General Medicine, Preventive Medicine, Nursing (3672 invited students); from 7th to 29th of April 2020; using an online questionnaire that included demographic and academic information, the Vietnamese version of the SF-36 Quality of Life questionnaire and the Fear of COVID-19 Scale (FCV-19S). Linear and modified Poisson regression was used to examine the association between quality of life, changes in quality of life and other factors. RESULTS: The number of participants was 1583 (response rate 43%). Among 8 dimensions of the SF-36 (ranged 0-100), Vitality had the lowest score with a median score of 46. The median physical composite score (PCS) of the sample was 40.6 (IQR:20.8-53.2), 33.5% of the sample had an above-population average PCS score. The median mental composite score (MCS) of the sample was 20.3 (IQR:3.8-31.7), and 98.2% had an MCS score below average. 9.9% (95%CI:8.5%-11.4%) of the population reported a significant negative change in the quality of life. Fear of COVID-19 was not associated with significant changes in quality of life, nor MCS while having some association with PCS (Coef:-5.39;95%CI:-3to-7.8). Perceived reduction in quality of life was also associated with: being on clinical rotation COVID-19 (PR:1.5;95%CI:1.05-2.2), difficulties affording health services (PR:1.4;95%CI:1.02-1.95), obesity (PR:2.38;95%CI:1.08-5.25) and chronic disease (PR:1.92;95%CI:1.23-3), typical symptoms (PR:1.85; 95%CI:1.23-2.78) and atypical symptoms of COVID-19 (PR:2.32;95%CI:1.41-3.81). CONCLUSION: The majority of medical and nursing students had below average quality of life, with lower vitality and mental composite health score in the settings of COVID-19. Perceived decrease in quality of life was associated with clinical rotation, difficulties affording healthcare services and was not associated with Fear of COVID-19.


Assuntos
COVID-19 , Estudantes de Enfermagem , Humanos , COVID-19/epidemiologia , Qualidade de Vida , Estudos Transversais , Pandemias , População do Sudeste Asiático
8.
AIDS Care ; 34(7): 887-893, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34133248

RESUMO

Physical and psychological symptoms among people living with HIV (PLWH) adversely affect quality of life and treatment adherence. Study objectives were: (i) to determine validity and reliability of a Vietnamese translation of the Memorial Symptom Assessment Scale-Short Form (MSAS-SF) among PLWH in Vietnam; (ii) to measure prevalence and burden of physical and psychological symptoms using the MSAS-SF including the Global Distress Index (GDI), Physical Distress subscale (PHYS), and Psychological Distress subscale (PSY); (iii) to identify symptom burden risk factors. We recruited 567 patients. Cronbach's alpha scores were: total MSAS-SF 0.91, GDI 0.83, PHYS 0.85, PSYCH 0.81. The scale showed good discriminant validity (low vs high function) (p < 0.001). The mean number of symptoms was 7.66, and the most prevalent were "worrying" (41.6%), "lack of energy" (40.6%), "feeling irritable" (40.4%), and "feeling sad" (39.2%). Monthly income below the poverty line was independently associated with increased: GDI,, PHYS, and PSY and a greater number of symptoms. The Vietnamese version of the MSAS-SF is valid to measure symptom prevalence and burden in HIV-positive populations. Here is a high symptom prevalence and burden among PLWH in Vietnam, especially those living in poverty, and a great need for palliative care integrated with HIV treatment.


Assuntos
Infecções por HIV , Qualidade de Vida , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Prevalência , Reprodutibilidade dos Testes , Autorrelato , Vietnã/epidemiologia
9.
mBio ; 12(4): e0067621, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34253054

RESUMO

Various toxic compounds disrupt bacterial physiology. While bacteria harbor defense mechanisms to mitigate the toxicity, these mechanisms are often coupled to the physiological state of the cells and become ineffective when the physiology is severely disrupted. Here, we characterized such feedback by exposing Escherichia coli to protonophores. Protonophores dissipate the proton motive force (PMF), a fundamental force that drives physiological functions. We found that E. coli cells responded to protonophores heterogeneously, resulting in bimodal distributions of cell growth, substrate transport, and motility. Furthermore, we showed that this heterogeneous response required active efflux systems. The analysis of underlying interactions indicated the heterogeneous response results from efflux-mediated positive feedback between PMF and protonophores' action. Our studies have broad implications for bacterial adaptation to stress, including antibiotics. IMPORTANCE An electrochemical proton gradient across the cytoplasmic membrane, alternatively known as proton motive force, energizes vital cellular processes in bacteria, including ATP synthesis, nutrient uptake, and cell division. Therefore, a wide range of organisms produce the agents that collapse the proton motive force, protonophores, to gain a competitive advantage. Studies have shown that protonophores have significant effects on microbial competition, host-pathogen interaction, and antibiotic action and resistance. Furthermore, protonophores are extensively used in various laboratory studies to perturb bacterial physiology. Here, we have characterized cell growth, substrate transport, and motility of Escherichia coli cells exposed to protonophores. Our findings demonstrate heterogeneous effects of protonophores on cell physiology and the underlying mechanism.


Assuntos
Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Proteínas de Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Ionóforos de Próton/farmacologia , Força Próton-Motriz , Transporte Biológico , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli/genética
10.
Mol Cells ; 44(3): 168-178, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33795534

RESUMO

The retinal pigment epithelium (RPE) forms a monolayer sheet separating the retina and choroid in vertebrate eyes. The polarized nature of RPE is maintained by distributing membrane proteins differentially along apico-basal axis. We found the distributions of these proteins differ in embryonic, post-natal, and mature mouse RPE, suggesting developmental regulation of protein trafficking. Thus, we deleted tumor susceptibility gene 101 (Tsg101), a key component of endosomal sorting complexes required for transport (ESCRT), in embryonic and mature RPE to determine whether ESCRT-mediated endocytic protein trafficking correlated with the establishment and maintenance of RPE polarity. Loss of Tsg101 severely disturbed the polarity of RPE, which forms irregular aggregates exhibiting non-polarized distribution of cell adhesion proteins and activation of epidermal growth factor receptor signaling. These findings suggest that ESCRT-mediated protein trafficking is essential for the development and maintenance of RPE cell polarity.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Células Epiteliais/metabolismo , Proteínas de Membrana/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Fatores de Transcrição/metabolismo , Animais , Polaridade Celular/fisiologia , Camundongos , Epitélio Pigmentado da Retina/citologia
11.
Support Care Cancer ; 29(8): 4791-4798, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33537888

RESUMO

PURPOSE: Cancer is a leading cause of death in Vietnam. To maximize quality of life (QOL) at the end of life, valid and clinically useful instruments are needed to assess palliative care needs and the effectiveness of palliative care interventions. METHODS: We aimed to (i) determine psychometric properties of the Vietnamese version of the WHO abbreviated quality of life scale (WHOQOL-BREFVN) among advanced cancer patients, (ii) measure HR-QOL, and (iii) identify predictors of HR-QOL. We collected demographic, clinical, and HR-QOL data from stage III/IV adult cancer patients at two major Vietnamese cancer centers. We determined the internal consistency (Cronbach's alpha), construct validity (confirmatory factor analysis (CFA)), and discriminant validity (known-groups comparison) of the Vietnamese instrument. HR-QOL was analyzed descriptively. Multinomial logistic regressions identified predictors of HR-QOL. RESULTS: A total of 825 patients participated. Missing data were completely at random (MCAR) (chi-square = 14.270, df = 14, p = 0.430). Cronbach's alpha for all items was 0.904. CFA loadings of physical, psychological, social relationship, and environment domains onto HR-QOL were 0.81, 0.82, 0.34, and 0.75, respectively. Prediction of scores differed significantly by functional status (Wilks' lambda = 0.784, chi-square = 197.546, df = 4, p < 0.01, correct prediction = 74.6%). HR-QOL was reported as very bad/bad by n = 188 patients (22.8%) and general health as very bad/bad by n = 430 (52.1%). Multinomial logistic regression (likelihood ratio test: chi-square = 35.494, df = 24, p = 0.061, correct prediction = 62.2%) and the Pearson correlations revealed worse HR-QOL was associated with inpatient status, high ECOG score, and having dependent children. CONCLUSION: The Vietnamese version of the WHOQOL-BREF has excellent internal consistency reliability and sound construct and discriminant validity in advanced cancer patients. Advanced cancer inpatients, those with dependent children, and those with poorer physical function appear to have the greatest palliative care needs.


Assuntos
Neoplasias/psicologia , Qualidade de Vida/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Autorrelato , Vietnã , Adulto Jovem
12.
Health Psychol Open ; 7(2): 2055102920953049, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32963799

RESUMO

A cross-sectional study was conducted among 262 newly admitted patients of a cancer hospital in Vietnam. The Vietnamese version EORTC-30 questionnaire 3.0 was used to interviews patients during the first week after their admission. Lower global quality of life and physical functioning scores were significantly associated with older age, lung and gastrointestinal cancers. Emotional functioning score was lower among female patients as compared to males. Financial difficulty was an important preditor for almost all functional scales. Management of early symptoms, providing early emotional supports and appropriate policies to reduce financial difficulty are important to improve cancer patients' quality of life.

13.
J Phys Condens Matter ; 32(38): 385703, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32422609

RESUMO

In this paper, we use supersymmetry formalism to study (2 + 1) dimensional Dirac-Weyl equation describing the motion of electrons in different axially symmetric carbon allotrope surfaces under the influence of crossed electromagnetic fields. In particular, we consider three carbon allotrope with different geometrical shapes and properties: open, half-open and closed geometries. The effect of the electric field and geometry on Landau levels and orbital magnetization has been examined. It has been shown that at a critical electric field the orbital magnetization exhibits a discontinuity which is associated with the collapse of Landau levels.

14.
J Phys Condens Matter ; 31(30): 305301, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30990465

RESUMO

In this paper relativistic Landau levels on a carbon pseudosphere, whose curvature is a negative constant K = -R -2, are investigated analytically in the presence of orthogonal electric and magnetic fields. It has been shown that the magnetic field tends to create bound states while the electric field tends to destroy them. Consequently there exists a critical electric field such that beyond this critical field the Landau levels collapse although negative curvature of the pseudosphere acts towards preventing the collapse of Landau levels at the critical value.

15.
Nat Microbiol ; 3(6): 741-748, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29760462

RESUMO

Bacteria adapt to environmental stress by producing proteins that provide stress protection. However, stress can severely perturb the kinetics of gene expression, disrupting protein production. Here, we characterized how Escherichia coli mitigates such perturbations under nutrient stress through the kinetic coordination of transcription and translation. We observed that, when translation became limiting under nitrogen starvation, transcription elongation slowed accordingly. This slowdown was mediated by (p)ppGpp, the alarmone whose primary role is thought to be promoter regulation. This kinetic coordination by (p)ppGpp was critical for the robust synthesis of gene products. Surprisingly, under carbon starvation, (p)ppGpp was dispensable for robust synthesis. Characterization of the underlying kinetics revealed that under carbon starvation, transcription became limiting, and translation aided transcription elongation. This mechanism naturally coordinated transcription with translation, alleviating the need for (p)ppGpp as a mediator. These contrasting mechanisms for coordination resulted in the condition-dependent effects of (p)ppGpp on global protein synthesis and starvation survival. Our findings reveal a kinetic aspect of gene expression plasticity, establishing (p)ppGpp as a condition-dependent global effector of gene expression.


Assuntos
Carbono/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/crescimento & desenvolvimento , Nitrogênio/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Guanosina Pentafosfato/metabolismo , Guanosina Tetrafosfato/metabolismo , Hibridização in Situ Fluorescente , Cinética , Biossíntese de Proteínas , Imagem Individual de Molécula , Transcrição Gênica
16.
Elife ; 72018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29508699

RESUMO

Effective antibiotic use that minimizes treatment failures remains a challenge. A better understanding of how bacterial populations respond to antibiotics is necessary. Previous studies of large bacterial populations established the deterministic framework of pharmacodynamics. Here, characterizing the dynamics of population extinction, we demonstrated the stochastic nature of eradicating bacteria with antibiotics. Antibiotics known to kill bacteria (bactericidal) induced population fluctuations. Thus, at high antibiotic concentrations, the dynamics of bacterial clearance were heterogeneous. At low concentrations, clearance still occurred with a non-zero probability. These striking outcomes of population fluctuations were well captured by our probabilistic model. Our model further suggested a strategy to facilitate eradication by increasing extinction probability. We experimentally tested this prediction for antibiotic-susceptible and clinically-isolated resistant bacteria. This new knowledge exposes fundamental limits in our ability to predict bacterial eradication. Additionally, it demonstrates the potential of using antibiotic concentrations that were previously deemed inefficacious to eradicate bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Bioestatística , Modelos Estatísticos
17.
Radiat Prot Dosimetry ; 181(3): 208-213, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29415136

RESUMO

The radioactivity concentrations of 226Ra, 232Th and 40K natural radionuclides in Lao Portland cement samples were measured using a gamma-spectrometry with a HPGe detector. The activity concentrations were found to vary from 28.32 ± 2.23 to 65.50 ± 2.83 Bq kg-1 with a mean value of 41.12 ± 2.44 Bq kg-1 for 226Ra; from 7.25 ± 2.00 to 44.01 ± 2.45 Bq kg-1 with a mean of 16.60 ± 2.37 Bq kg-1 for 232Th and from 49.19 ± 4.27 to 196.74 ± 4.75 Bq kg-1 with a mean of 141.48 ± 4.50 Bq kg-1 for 40K, respectively. The radiological parameters were estimated to assess the potential radiological hazard including radium equivalent activity, total external absorbed dose rate in outdoor air at 1 m above the earth's surface, the annual effective dose, the gamma and alpha-indices were calculated using the activity concentrations of 226Ra, 232Th and 40K. The results obtained in this study show no significant radiological hazards arising from using Lao Portland cement for building construction.


Assuntos
Radiação de Fundo , Materiais de Construção/análise , Radioisótopos de Potássio/análise , Monitoramento de Radiação , Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise , Tório/análise , Humanos , Doses de Radiação
18.
ACS Appl Mater Interfaces ; 8(1): 278-84, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26703760

RESUMO

Cephalopods possess remarkable camouflage capabilities, which are enabled by their complex skin structure and sophisticated nervous system. Such unique characteristics have in turn inspired the design of novel functional materials and devices. Within this context, recent studies have focused on investigating the self-assembly, optical, and electrical properties of reflectin, a protein that plays a key role in cephalopod structural coloration. Herein, we report the discovery that reflectin constitutes an effective material for the growth of human neural stem/progenitor cells. Our findings may hold relevance both for understanding cephalopod embryogenesis and for developing improved protein-based bioelectronic devices.


Assuntos
Materiais Biocompatíveis/farmacologia , Células-Tronco Neurais/citologia , Proteínas/farmacologia , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Decapodiformes/química , Humanos , Microscopia de Fluorescência , Células-Tronco Neurais/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos
19.
ACS Appl Mater Interfaces ; 7(2): 1348-54, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25545033

RESUMO

Portable energy storage devices have gained special attention due to the growing demand for portable electronics. Herein, an all-solid-state supercapacitor is successfully fabricated based on a poly(vinyl alcohol)-H3PO4 (PVA-H3PO4) polymer electrolyte and a reduced graphene oxide (RGO) membrane electrode prepared by electrophoretic deposition (EPD). The RGO electrode fabricated by EPD contains an in-plane layer-by-layer alignment and a moderate porosity that accommodate the electrolyte ions. The all-solid-state RGO supercapacitor is thoroughly tested to give high specific volumetric capacitance (108 F cm(-3)) and excellent energy and power densities (7.5 Wh cm(-3) and 2.9 W cm(-3), respectively). In addition, the all-solid-state RGO supercapacitor exhibits an ultralong lifetime for as long as 180 days (335 000 cycles), which is an ultrahigh cycling capability for a solid-state supercapacitor. The RGO is also tested for being used as a transparent supercapacitor electrode demonstrating its possible use in various transparent optoelectronic devices. Due to the facile scale-up capability of the EPD process and RGO dispersion, the developed all-solid-state supercapacitor is highly applicable to large-area portable energy storage devices.

20.
Proc Natl Acad Sci U S A ; 111(45): 16148-53, 2014 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-25349416

RESUMO

Neural stem cells are multipotent cells with the ability to differentiate into neurons, astrocytes, and oligodendrocytes. Lineage specification is strongly sensitive to the mechanical properties of the cellular environment. However, molecular pathways transducing matrix mechanical cues to intracellular signaling pathways linked to lineage specification remain unclear. We found that the mechanically gated ion channel Piezo1 is expressed by brain-derived human neural stem/progenitor cells and is responsible for a mechanically induced ionic current. Piezo1 activity triggered by traction forces elicited influx of Ca(2+), a known modulator of differentiation, in a substrate-stiffness-dependent manner. Inhibition of channel activity by the pharmacological inhibitor GsMTx-4 or by siRNA-mediated Piezo1 knockdown suppressed neurogenesis and enhanced astrogenesis. Piezo1 knockdown also reduced the nuclear localization of the mechanoreactive transcriptional coactivator Yes-associated protein. We propose that the mechanically gated ion channel Piezo1 is an important determinant of mechanosensitive lineage choice in neural stem cells and may play similar roles in other multipotent stem cells.


Assuntos
Sinalização do Cálcio/fisiologia , Ativação do Canal Iônico/fisiologia , Canais Iônicos/metabolismo , Mecanotransdução Celular/fisiologia , Células-Tronco Multipotentes/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Técnicas de Silenciamento de Genes , Humanos , Canais Iônicos/genética , Masculino , Células-Tronco Multipotentes/citologia , Células-Tronco Neurais/citologia
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