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1.
Sci Rep ; 13(1): 17846, 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37857808

RESUMEN

Demand is increasing for photovoltaics (PVs) as a result of the development of the Internet of Things and edge computing technologies. As the lighting environment is different for the applications, thus, PVs must be adjustable to various light environments in which systems are installed. PVs should therefore be capable of easily changing their morphology without damaging the cells. To address this problem, in this work, a three-dimensional (3D) structure that increases power output under omnidirectional light was applied to a crystalline silicon solar cell array using a block-type method. The resultant block-type 3D indoor PV could operate a Bluetooth low-energy module in conjunction with a power management integrated circuit when the illuminance was 532 lx and 1620 lx and each PV installation area was 129.9cm2 and 32.48 cm2 respectively.

2.
JMIR Mhealth Uhealth ; 11: e42851, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37788060

RESUMEN

BACKGROUND: Mindfulness-based training programs have consistently shown efficacy in stress reduction. However, questions regarding the optimal duration and most effective delivery methods remain. OBJECTIVE: This research explores a 4-week neurofeedback-assisted mindfulness training for employees via a mobile app. The study's core query is whether incorporating neurofeedback can amplify the benefits on stress reduction and related metrics compared with conventional mindfulness training. METHODS: A total of 92 full-time employees were randomized into 3 groups: group 1 received mobile mindfulness training with neurofeedback assistance (n=29, mean age 39.72 years); group 2 received mobile mindfulness training without neurofeedback (n=32, mean age 37.66 years); and group 3 were given self-learning paper materials on stress management during their first visit (n=31, mean age 38.65 years). The primary outcomes were perceived stress and resilience scales. The secondary outcomes were mindfulness awareness, emotional labor, occupational stress, insomnia, and depression. Heart rate variability and electroencephalography were measured for physiological outcomes. These measurements were collected at 3 different times, namely, at baseline, immediately after training, and at a 4-week follow-up. The generalized estimating equation model was used for data analysis. RESULTS: The 4-week program showed significant stress reduction (Wald χ22=107.167, P<.001) and improvements in psychological indices including resilience, emotional labor, insomnia, and depression. A significant interaction was observed in resilience (time × group, Wald χ42=10.846, P=.02). The post hoc analysis showed a statistically significant difference between groups 1 (least squares mean [LSM] 21.62, SE 0.55) and 3 (LSM 19.90, SE 0.61) at the posttraining assessment (P=.008). Group 1 showed a significant improvement (P<.001) at the posttraining assessment, with continued improvements through the 1-month follow-up assessment period (LSM 21.55, SE 0.61). Physiological indices were analyzed only for data of 67 participants (22 in group 1, 22 in group 2, and 23 in group 3) due to the data quality. The relaxation index (ratio of alpha to high beta power) from the right electroencephalography channel showed a significant interaction (time × group, Wald χ22=6.947, P=.03), with group 1 revealing the highest improvement (LSM 0.43, SE 0.15) compared with groups 2 (LSM -0.11, SE 0.10) and 3 (LSM 0.12, SE 0.10) at the 1-month follow-up assessment. CONCLUSIONS: The study demonstrated that the neurofeedback-assisted group achieved superior outcomes in resilience and relaxation during the 4-week mobile mindfulness program. Further research with larger samples and long-term follow-up is warranted. TRIAL REGISTRATION: ClinicalTrials.gov NCT03787407; https://clinicaltrials.gov/ct2/show/NCT03787407.


Asunto(s)
Atención Plena , Aplicaciones Móviles , Neurorretroalimentación , Estrés Laboral , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Adulto , Atención Plena/métodos , Estrés Laboral/terapia , Estrés Laboral/psicología
3.
J Biophotonics ; 16(12): e202300232, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37651611

RESUMEN

A Q-switched laser system has been used in a single-pulse mode for skin melasma treatments because of instant heat deposition in the target. Despite the efficient ablation of the melanophores in the skin, the single, high-fluence pulse often causes undesirable damage to the surrounding tissue, leading to high recurrence rates. This study aims to investigate the feasibility of dual-optical pulses with a temporal energy distribution on the melasma treatment in in vivo zebrafish models in comparison to that of the single optical pulse. Based on the optical detection, the dual-optical pulses had a temporal energy distribution ratio of 4:1 and an interval of 61 µs between the two consecutive pulses. According to the histological analysis, the dual pulses removed melanophores and induced a few apoptotic nuclei with minimal recurrence. This study demonstrated that the feasibility of dual-optical pulses (energy ratio = 4:1) could enhance the laser ablation performance in vivo.


Asunto(s)
Terapia por Láser , Melanosis , Animales , Pez Cebra , Melanosis/etiología , Melanosis/cirugía , Calor
4.
Sci Rep ; 6: 36527, 2016 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-27827433

RESUMEN

The omega loop in ß-lactamases plays a pivotal role in substrate recognition and catalysis, and some mutations in this loop affect the adaptability of the enzymes to new antibiotics. Various mutations, including substitutions, deletions, and intragenic duplications resulting in tandem repeats (TRs), have been associated with ß-lactamase substrate spectrum extension. TRs are unique among the mutations as they cause severe structural perturbations in the enzymes. We explored the process by which TRs are accommodated in order to test the adaptability of the omega loop. Structures of the mutant enzymes showed that the extra amino acid residues in the omega loop were freed outward from the enzyme, thereby maintaining the overall enzyme integrity. This structural adjustment was accompanied by disruptions of the internal α-helix and hydrogen bonds that originally maintained the conformation of the omega loop and the active site. Consequently, the mutant enzymes had a relaxed binding cavity, allowing for access of new substrates, which regrouped upon substrate binding in an induced-fit manner for subsequent hydrolytic reactions. Together, the data demonstrate that the design of the binding cavity, including the omega loop with its enormous adaptive capacity, is the foundation of the continuous evolution of ß-lactamases against new drugs.


Asunto(s)
beta-Lactamasas/metabolismo , Secuencia de Aminoácidos , Antibacterianos/química , Antibacterianos/farmacología , Ceftazidima/farmacología , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Mutación , Especificidad por Sustrato , Secuencias Repetidas en Tándem , beta-Lactamasas/química , beta-Lactamasas/genética
5.
J Allergy Clin Immunol ; 137(3): 852-60, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26431583

RESUMEN

BACKGROUND: Atopic dermatitis (AD) is a serious global epidemic associated with a modern lifestyle. OBJECTIVE: Although aberrant interactions between gut microbes and the intestinal immune system have been implicated in this skin disease, the nature of the microbiome dysfunction underlying the disease remains unclear. METHODS: The gut microbiome from 132 subjects, including 90 patients with AD, was analyzed by using 16S rRNA gene and metagenome sequence analyses. Reference genomes from the Human Microbiome Project and the KEGG Orthology database were used for metagenome analyses. Short-chain fatty acids in fecal samples were compared by using gas chromatographic-mass spectrometric analyses. RESULTS: We show that enrichment of a subspecies of the major gut species Faecalibacterium prausnitzii is strongly associated with AD. In addition, the AD microbiome was enriched in genes encoding the use of various nutrients that could be released from damaged gut epithelium, reflecting a bloom of auxotrophic bacteria. Fecal samples from patients with AD showed decreased levels of butyrate and propionate, which have anti-inflammatory effects. This is likely a consequence of an intraspecies compositional change in F prausnitzii that reduces the number of high butyrate and propionate producers, including those related to the strain A2-165, a lack of which has been implicated in patients with Crohn disease. CONCLUSIONS: The data suggest that feedback interactions between dysbiosis in F prausnitzii and dysregulation of gut epithelial inflammation might underlie the chronic progression of AD by resulting in impairment of the gut epithelial barrier, which ultimately leads to aberrant TH2-type immune responses to allergens in the skin.


Asunto(s)
Clostridiales , Dermatitis Atópica/etiología , Disbiosis , Microbioma Gastrointestinal , Clostridiales/clasificación , Clostridiales/genética , Clostridiales/metabolismo , Análisis por Conglomerados , Biología Computacional/métodos , Heces/microbiología , Femenino , Humanos , Masculino , Metagenoma , Metagenómica , Modelos Biológicos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
6.
Antimicrob Agents Chemother ; 59(12): 7602-10, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26416862

RESUMEN

In many Gram-negative pathogens, mutations in the key cell wall-recycling enzyme AmpD (N-acetyl-anhydromuramyl-L-alanine amidase) affect the activity of the regulator AmpR, which leads to the expression of AmpC ß-lactamase, conferring resistance to expanded-spectrum cephalosporin antibiotics. Burkholderia cepacia complex (Bcc) species also have these Amp homologs; however, the regulatory circuitry and the nature of causal ampD mutations remain to be explored. A total of 92 ampD mutants were obtained, representing four types of mutations: single nucleotide substitution (causing an amino acid substitution or antitermination of the enzyme), duplication, deletion, and IS element insertion. Duplication, which can go through reversion, was the most frequent type. Intriguingly, mutations in ampD led to the induction of two ß-lactamases, AmpC and PenB. Coregulation of AmpC and PenB in B. cenocepacia, and likely also in many Bcc species with the same gene organization, poses a serious threat to human health. This resistance mechanism is of evolutionary optimization in that ampD is highly prone to mutations allowing rapid response to antibiotic challenge, and many of the mutations are reversible in order to resume cell wall recycling when the antibiotic challenge is relieved.


Asunto(s)
Proteínas Bacterianas/genética , Burkholderia cenocepacia/genética , Pared Celular/genética , Resistencia a las Cefalosporinas/genética , Regulación Bacteriana de la Expresión Génica , N-Acetil Muramoil-L-Alanina Amidasa/genética , beta-Lactamasas/genética , Secuencia de Aminoácidos , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Burkholderia cenocepacia/efectos de los fármacos , Burkholderia cenocepacia/metabolismo , Pared Celular/efectos de los fármacos , Pared Celular/metabolismo , Cefalosporinas/farmacología , Elementos Transponibles de ADN , Prueba de Complementación Genética , Isoenzimas/genética , Isoenzimas/metabolismo , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Mutación , N-Acetil Muramoil-L-Alanina Amidasa/metabolismo , Polimorfismo Genético , Alineación de Secuencia , beta-Lactamasas/metabolismo
7.
PLoS Genet ; 10(9): e1004640, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25233343

RESUMEN

Expansion or shrinkage of existing tandem repeats (TRs) associated with various biological processes has been actively studied in both prokaryotic and eukaryotic genomes, while their origin and biological implications remain mostly unknown. Here we describe various duplications (de novo TRs) that occurred in the coding region of a ß-lactamase gene, where a conserved structure called the omega loop is encoded. These duplications that occurred under selection using ceftazidime conferred substrate spectrum extension to include the antibiotic. Under selective pressure with one of the original substrates (amoxicillin), a high level of reversion occurred in the mutant ß-lactamase genes completing a cycle back to the original substrate spectrum. The de novo TRs coupled with reversion makes a genetic toggling mechanism enabling reversible switching between the two phases of the substrate spectrum of ß-lactamases. This toggle exemplifies the effective adaptation of de novo TRs for enhanced bacterial survival. We found pairs of direct repeats that mediated the DNA duplication (TR formation). In addition, we found different duos of sequences that mediated the DNA duplication. These novel elements-that we named SCSs (same-strand complementary sequences)-were also found associated with ß-lactamase TR mutations from clinical isolates. Both direct repeats and SCSs had a high correlation with TRs in diverse bacterial genomes throughout the major phylogenetic lineages, suggesting that they comprise a fundamental mechanism shaping the bacterial evolution.


Asunto(s)
Secuencias Repetidas en Tándem/genética , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Alelos , Antibacterianos/metabolismo , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/genética , Secuencia de Bases , Evolución Biológica , Ceftazidima/metabolismo , Ceftazidima/farmacología , Duplicación de Gen , Genoma Bacteriano , Pruebas de Sensibilidad Microbiana , Modelos Biológicos , Datos de Secuencia Molecular , Filogenia , Mutación Puntual , Especificidad por Sustrato/genética
8.
Antimicrob Agents Chemother ; 58(10): 6265-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25049254

RESUMEN

We describe four new deletion mutations in a class A ß-lactamase PenA in Burkholderia thailandensis, each conferring an extended substrate spectrum. Single-amino-acid deletions T171del, I173del, and P174del and a two-amino-acid deletion, R165_T167delinsP, occurred in the omega loop, increasing the flexibility of the binding cavity. This rare collection of mutations has significance, allowing exploration of the diverse evolutionary trajectories of ß-lactamases and as potential future mutations conferring high-level ceftazidime resistance on isolates from clinical settings, compared with amino acid substitution mutations.


Asunto(s)
Burkholderia/enzimología , Burkholderia/genética , Eliminación de Secuencia/genética , beta-Lactamasas/genética
9.
Mol Med Rep ; 8(5): 1425-31, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24064967

RESUMEN

Angiogenesis inhibition is an attractive therapeutic strategy in the management of solid tumors. Vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) are key factors in growth and neovascularization of hepatocellular carcinoma (HCC). Brivanib is a novel, orally available dual tyrosine kinase inhibitor that selectively targets the key angiogenesis receptors VEGF­R2, FGF­R1 and FGF­R2. Recently, high­resolution magic angle spinning magnetic resonance spectroscopy (HR­MAS MRS) has provided the opportunity to investigate more detailed metabolic profiles from intact tissue specimens that are correlated with histopathology and is thus, a promising tool for monitoring changes induced by treatment. In the present study, 1H HR­MAS MRS and immunohistochemistry were used to investigate the antitumor efficacy of brivanib in HCC xenograft models. Tumor growth was significantly suppressed in brivanib­treated mice compared with the controls and treatment was associated with the inhibition of angiogenesis, increased apoptosis and inhibition of cell proliferation. Furthermore, HR­MAS techniques showed altered metabolic profiles between the two groups. HR­MAS spectra demonstrated a significant decrease in choline metabolite levels in the treated groups, concurrent with decreased cell proliferation and increased apoptosis. The results showed that 1H HR­MAS MRS provides quantitative metabolite information that may be used to analyze the efficacy of brivanib treatment in Hep3B tumor xenografts. Thus, the HR­MAS MRS technique may be a complementary method to support histopathological results and increase its potential for use in the clinic.


Asunto(s)
Alanina/análogos & derivados , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Espectroscopía de Resonancia Magnética/métodos , Triazinas/uso terapéutico , Alanina/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/metabolismo , Proliferación Celular/efectos de los fármacos , Humanos , Técnicas para Inmunoenzimas , Neoplasias Hepáticas/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
10.
PLoS Pathog ; 6(5): e1000922, 2010 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-20523904

RESUMEN

The equine-associated obligate pathogen Burkholderia mallei was developed by reductive evolution involving a substantial portion of the genome from Burkholderia pseudomallei, a free-living opportunistic pathogen. With its short history of divergence (approximately 3.5 myr), B. mallei provides an excellent resource to study the early steps in bacterial genome reductive evolution in the host. By examining 20 genomes of B. mallei and B. pseudomallei, we found that stepwise massive expansion of IS (insertion sequence) elements ISBma1, ISBma2, and IS407A occurred during the evolution of B. mallei. Each element proliferated through the sites where its target selection preference was met. Then, ISBma1 and ISBma2 contributed to the further spread of IS407A by providing secondary insertion sites. This spread increased genomic deletions and rearrangements, which were predominantly mediated by IS407A. There were also nucleotide-level disruptions in a large number of genes. However, no significant signs of erosion were yet noted in these genes. Intriguingly, all these genomic modifications did not seriously alter the gene expression patterns inherited from B. pseudomallei. This efficient and elaborate genomic transition was enabled largely through the formation of the highly flexible IS-blended genome and the guidance by selective forces in the host. The detailed IS intervention, unveiled for the first time in this study, may represent the key component of a general mechanism for early bacterial evolution in the host.


Asunto(s)
Burkholderia mallei/crecimiento & desarrollo , Burkholderia mallei/genética , Evolución Molecular , Genoma Bacteriano , Muermo/microbiología , Animales , Burkholderia pseudomallei/genética , Burkholderia pseudomallei/crecimiento & desarrollo , Elementos Transponibles de ADN/genética , ADN Bacteriano/genética , Eliminación de Gen , Regulación Bacteriana de la Expresión Génica , Reordenamiento Génico/genética , Variación Genética , Caballos , Humanos , Ratones , Mutación/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Filogenia
11.
Mol Cells ; 27(2): 237-41, 2009 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-19277507

RESUMEN

Pathogens Burkholderia pseudomallei (Bp) and Burkholderia mallei (Bm) contain a large number (> 12,000) of Simple Sequence Repeats (SSRs). To study the extent to which these features have contributed to the diversification of genes, we have conducted comparative studies with nineteen genomes of these bacteria. We found 210 genes with characteristic types of SSR variations. SSRs with nonamer repeat units were the most abundant, followed by hexamers and trimers. Amino acids with smaller and nonpolar R-groups are preferred to be encoded by the variant SSRs, perhaps due to their minimal impacts to protein functionality. A majority of these genes appears to code for surface or secreted proteins that may directly interact with the host factors during pathogenesis or other environmental factors. There also are others that encode diverse functions in the cytoplasm, and this protein variability may reflect an extensive involvement of phase variation in survival and adaptation of these pathogens.


Asunto(s)
Proteínas Bacterianas/genética , Burkholderia mallei/genética , Burkholderia pseudomallei/genética , Variación Genética , Genoma Bacteriano , Repeticiones de Minisatélite , Proteínas Bacterianas/clasificación , Secuencia de Bases , ADN Bacteriano , Datos de Secuencia Molecular , Alineación de Secuencia
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