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1.
ACS Energy Lett ; 8(11): 4885-4887, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37969253

RESUMO

For the first time, large-area, flexible organic-inorganic tin perovskite solar modules are fabricated by means of an industry-compatible and scalable blade-coating technique. An 8-cell interconnected mini module with dimensions of 25 cm2 (active area = 8 × 1.5 cm2) reached 5.7% power conversion efficiency under 1000 W/m2 (AM 1.5G) and 9.4% under 2000 lx (white-LED).

2.
Nat Methods ; 20(11): 1716-1728, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37813990

RESUMO

Engineered transactivation domains (TADs) combined with programmable DNA binding platforms have revolutionized synthetic transcriptional control. Despite recent progress in programmable CRISPR-Cas-based transactivation (CRISPRa) technologies, the TADs used in these systems often contain poorly tolerated elements and/or are prohibitively large for many applications. Here, we defined and optimized minimal TADs built from human mechanosensitive transcription factors. We used these components to construct potent and compact multipartite transactivation modules (MSN, NMS and eN3x9) and to build the CRISPR-dCas9 recruited enhanced activation module (CRISPR-DREAM) platform. We found that CRISPR-DREAM was specific and robust across mammalian cell types, and efficiently stimulated transcription from diverse regulatory loci. We also showed that MSN and NMS were portable across Type I, II and V CRISPR systems, transcription activator-like effectors and zinc finger proteins. Further, as proofs of concept, we used dCas9-NMS to efficiently reprogram human fibroblasts into induced pluripotent stem cells and demonstrated that mechanosensitive transcription factor TADs are efficacious and well tolerated in therapeutically important primary human cell types. Finally, we leveraged the compact and potent features of these engineered TADs to build dual and all-in-one CRISPRa AAV systems. Altogether, these compact human TADs, fusion modules and delivery architectures should be valuable for synthetic transcriptional control in biomedical applications.


Assuntos
Sistemas CRISPR-Cas , Regulação da Expressão Gênica , Animais , Humanos , Ativação Transcricional , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fibroblastos/metabolismo , Mamíferos/metabolismo
3.
J Am Chem Soc ; 145(1): 413-421, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36542862

RESUMO

Genome mining of cryptic natural products (NPs) remains challenging, especially in filamentous fungi, owing to their complex genetic regulation. Increasing evidence indicates that several epigenetic modifications often act cooperatively to control fungal gene transcription, yet the ability to predictably manipulate multiple genes simultaneously is still largely limited. Here, we developed a multiplex base-editing (MBE) platform that significantly improves the capability and throughput of fungal genome manipulation, leading to the simultaneous inactivation of up to eight genes using a single transformation. We then employed MBE to inactivate three negative epigenetic regulators combinatorially in Aspergillus nidulans, enabling the activation of eight cryptic gene clusters compared to the wild-type strains. A group of novel NPs harboring unique cichorine and polyamine hybrid chemical scaffolds were identified, which were not reported previously. We envision that our scalable and efficient MBE platform can be readily applied in other filamentous fungi for the genome mining of novel NPs, providing a powerful approach for the exploitation of fungal chemical diversity.


Assuntos
Aspergillus nidulans , Produtos Biológicos , Epigênese Genética , Genes Fúngicos , Genoma Fúngico , Fungos/genética , Aspergillus nidulans/genética , Família Multigênica
4.
J Oral Maxillofac Res ; 13(3): e1, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36382016

RESUMO

Objectives: The aim of the present systematic review was to evaluate the dimensional influence of the epithelialized tissue graft harvested from the palate in the postoperative pain. Material and Methods: Research was conducted in electronic databases Cochrane Library, Embase, LILACS, PubMed, Scopus, and Web of Science upwards May 15, 2022. Studies that reported the influence of graft dimensions of palatal epithelized harvesting on postoperative pain were eligible. The evaluation was made using the methodological quality assessment by Joanna Briggs Institute Critical Appraisal Checklist for randomized clinical trials and non-randomized studies and the level of evidence according to GRADE. Results: Four studies were included. The clinical and methodological heterogeneity among studies led to an analysed narrative. The postoperative pain was assessed during the period of 1 to 28 postoperative days. It was determined by using visual analog scale in three studies, while the evaluation was performed indirectly based on analgesics intake in one study. According to three studies, bigger graft sizes were associated with higher postoperative pain. The methodological quality assessment categorized two study as high (one randomized control trial and one non-randomized), and two as moderate (one randomized control trial and one non-randomized). The data was considered moderate. Conclusions: Based on the moderate certainty level, bigger graft sizes of palatal epithelized harvesting appear to promote more postoperative pain. Understanding the postoperative pain as a response to a graft extension may assist some clinical decisions regarding the surgical periodontal and peri-implant planning.

5.
ACS Synth Biol ; 11(10): 3239-3250, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36162812

RESUMO

CRISPR/Cas technologies have revolutionized the ability to redesign genomic information and tailor endogenous gene expression. Nevertheless, the discovery and development of new CRISPR/Cas systems has resulted in a lack of clarity surrounding the relative efficacies among these technologies in human cells. This deficit makes the optimal selection of CRISPR/Cas technologies in human cells unnecessarily challenging, which in turn hampers their adoption, and thus ultimately limits their utility. Here, we designed a series of endogenous testbed systems to methodically quantify and compare the genome editing, CRISPRi, and CRISPRa capabilities among 10 different natural and engineered Cas protein variants spanning Type II and Type V CRISPR/Cas families. We show that although all Cas protein variants are capable of genome editing and transcriptional control in human cells, hierarchies exist, particularly for genome editing and CRISPRa applications, wherein Cas9 ≥ Cas12a > Cas12e/Cas12j. Our findings also highlight the utility of our modular testbed platforms to rapidly and systematically quantify the functionality of practically any natural or engineered genomic-targeting Cas protein in human cells.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Humanos , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Genoma , Genômica
6.
Nucleic Acids Res ; 50(14): 7842-7855, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35849129

RESUMO

Nuclease-inactivated CRISPR/Cas-based (dCas-based) systems have emerged as powerful technologies to synthetically reshape the human epigenome and gene expression. Despite the increasing adoption of these platforms, their relative potencies and mechanistic differences are incompletely characterized, particularly at human enhancer-promoter pairs. Here, we systematically compared the most widely adopted dCas9-based transcriptional activators, as well as an activator consisting of dCas9 fused to the catalytic core of the human CBP protein, at human enhancer-promoter pairs. We find that these platforms display variable relative expression levels in different human cell types and that their transactivation efficacies vary based upon the effector domain, effector recruitment architecture, targeted locus and cell type. We also show that each dCas9-based activator can induce the production of enhancer RNAs (eRNAs) and that this eRNA induction is positively correlated with downstream mRNA expression from a cognate promoter. Additionally, we use dCas9-based activators to demonstrate that an intrinsic transcriptional and epigenetic reciprocity can exist between human enhancers and promoters and that enhancer-mediated tracking and engagement of a downstream promoter can be synthetically driven by targeting dCas9-based transcriptional activators to an enhancer. Collectively, our study provides new insights into the enhancer-mediated control of human gene expression and the use of dCas9-based activators.


Assuntos
Sistemas CRISPR-Cas , Elementos Facilitadores Genéticos , Regiões Promotoras Genéticas , Ativação Transcricional , Sistemas CRISPR-Cas/genética , Epigenômica , Regulação da Expressão Gênica , Humanos , Fragmentos de Peptídeos , RNA , Sialoglicoproteínas , Fatores de Transcrição/genética
7.
J Indian Soc Periodontol ; 26(2): 192-196, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35321303

RESUMO

Maxillary permanent canines are the second most frequent cases of impacted teeth; their resolution demands a multidisciplinary evaluation to delineate a viable treatment plan based on the individual esthetic and functional outcomes required. An impacted maxillary permanent canine which was ankylosed in a horizontal position was extracted followed by a regeneration technique, filling the bone defect with biomaterial. An implant was immediately installed in the alveolus of the extracted deciduous canine, and a connective tissue graft was buccally positioned. After the osseointegration period, a modified Palacci and Nowzari surgical technique was performed to gain papilla, and the implant was loaded with an interim restoration with a proper profile to manipulate the soft-tissue contour. Finally, the definitive restauration was cemented achieving the desired outcomes. The achieved clinical outcomes remain stable during a 2-year follow-up. A successful management of this challenge esthetic case lies in the details at surgical and prosthetic phases based in biological response of the peri-implant tissues.

8.
Dent Mater ; 37(4): 741-754, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33589269

RESUMO

OBJECTIVE: The objective of this study was to evaluate the combined effect of the sulfuric acid etching and an acidic adhesive conditioning on the shear bond strength of PEEK to a resin-matrix composite. MATERIALS AND METHODS: Forty PEEK specimens were assigned randomly to 4 groups for H2SO4 etching followed by universal adhesive (pH at 2.5) conditioning for 0, 1, 3, and 5 min. Thirty PEEK specimens were divided into 3 groups for only acidic adhesive conditioning for 0, 1, 3, and 5 min. After the light-curing of the adhesive, a nanohybrid resin composite was applied onto the surfaces and then light-cured following the manufacturer`s guidelines. All specimens were stored in distilled water at 37 °C for 24 h mechanical testing. Shear bond strength tests were performed using a universal testing machine. Surfaces were analyzed by SEM, light interferometry, FTIR, and liquid contact angle measurement. Statistical analysis was performed by one-way ANOVA and Tukey's post hoc tests (p < 0.05). RESULTS: No adhesion was achieved between untreated PEEK a resin-matrix composite, regardless of the adhesive conditioning time points. Shear bond strength of H2SO4-etched PEEK to resin-matrix composite increased with time (0 mmin. 4.95 ± 2.86 MPa < 1 min: 9.35 ± 2.26 MPa < 3 min: 17.84 ± 2.82 MPa < 5 min: 21.43 ± 5.00 MPa). SEM images revealed a significant modification of PEEK surface topography after the H2SO4 etching. SIGNIFICANCE: The acidic adhesive was unable to modify the untreated PEEK surface to establish an effective adhesion although a synergistic effect was noticed when the universal (acidic) adhesive was applied over a H2SO4-etched PEEK surface, thus improving the PEEK to resin-matrix composite adhesion.


Assuntos
Condicionamento Ácido do Dente , Colagem Dentária , Benzofenonas , Resinas Compostas , Cimentos Dentários , Análise do Estresse Dentário , Cetonas , Teste de Materiais , Polietilenoglicóis , Polímeros , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície
9.
Nat Commun ; 12(1): 896, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33563994

RESUMO

Histone phosphorylation is a ubiquitous post-translational modification that allows eukaryotic cells to rapidly respond to environmental stimuli. Despite correlative evidence linking histone phosphorylation to changes in gene expression, establishing the causal role of this key epigenomic modification at diverse loci within native chromatin has been hampered by a lack of technologies enabling robust, locus-specific deposition of endogenous histone phosphorylation. To address this technological gap, here we build a programmable chromatin kinase, called dCas9-dMSK1, by directly fusing nuclease-null CRISPR/Cas9 to a hyperactive, truncated variant of the human MSK1 histone kinase. Targeting dCas9-dMSK1 to human promoters results in increased target histone phosphorylation and gene activation and demonstrates that hyperphosphorylation of histone H3 serine 28 (H3S28ph) in particular plays a causal role in the transactivation of human promoters. In addition, we uncover mediators of resistance to the BRAF V600E inhibitor PLX-4720 in human melanoma cells using genome-scale screening with dCas9-dMSK1. Collectively, our findings enable a facile way to reshape human chromatin using CRISPR/Cas9-based epigenome editing and further define the causal link between histone phosphorylation and human gene activation.


Assuntos
Sistemas CRISPR-Cas , Epigenômica/métodos , Histonas/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Acetilação , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Linhagem Celular Tumoral , Cromatina/genética , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Indóis/farmacologia , Fosforilação , Regiões Promotoras Genéticas/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Sulfonamidas/farmacologia , Ativação Transcricional
10.
Clin Oral Investig ; 25(6): 3609-3622, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33200283

RESUMO

OBJECTIVE: To critically appraise available literature concerning the effect of cyanoacrylate tissue adhesive (CTA) in postoperative palatal pain management. MATERIALS AND METHODS: Electronic databases (Cochrane, PubMed, LILACS, Scopus, and Web of Science) were searched, complemented with grey literature databases up to June 2020. Studies reporting the effect of cyanoacrylate tissue adhesive compared to any other methods in postoperative palatal pain management were considered eligible. The risk of bias among and across included studies was assessed. RESULTS: Finally, four studies were considered eligible. Regarding free gingival graft (FGG), cyanoacrylate tissue adhesive with hemostatic sponge promoted less postoperative pain (PP) and analgesic consumption (AC). Also, cyanoacrylate tissue adhesive with platelet-rich fibrin produced less PP and more wound healing at the palatal area than cyanoacrylate tissue adhesive and wet gauze. Additionally, cyanoacrylate tissue adhesive promoted less PP and AC than wet gauze and suture. Concerning connective tissue graft (CTG), cyanoacrylate tissue adhesive, and suture produced similar PP, AC, and willingness for retreatment. CONCLUSIONS: Based on the low certainty level, cyanoacrylate tissue adhesive appears to promote less PP and AC than wet gauze and suture regarding FGG. Additionally, cyanoacrylate tissue adhesive appears to increase the effect of hemostatic sponge, contributing to the reduction of PP and AC. Regarding CTG, cyanoacrylate tissue adhesive appears to promote similar PP, AC, and willingness for retreatment than the suture. Therefore, cyanoacrylate tissue adhesive has shown promising usefulness for PP management in FGG, but not a clear benefit for CTG. CLINICAL RELEVANCE: The adoption of different agents for the protection of the palatal donor site following gingival harvesting procedures may provide better comfort to the patient.


Assuntos
Fibrina Rica em Plaquetas , Adesivos Teciduais , Cianoacrilatos , Humanos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Palato/cirurgia , Adesivos Teciduais/uso terapêutico
11.
Rev. colomb. ortop. traumatol ; 35(1): 99-104, 2021. ilus.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1378587

RESUMO

Se presenta un Caso Clínico de una paciente de género femenino, 90 años 6 meses de edad, con diagnóstico inicial de Coxartrosis Bilateral de Cadera. Se le realizó Reemplazo Total de Cadera hace 30 años del lado izquierdo (1990) con una Prótesis de Roy Camille, y hace 25 años se intervino el lado derecho (1997) con una Prótesis Bipolar Cementada. En el año 2019 se llevó a Revisión de Prótesis de Cadera.


We present a Clinical Case of a female patient, 90 years 6 months of age, with an initial diagnosis of Bilateral Hip Coxarthrosis. Total Hip Replacement was performed 30 years ago on the left side (1990) with Roy Camille Prosthesis, and 25 years ago the right side (1997) was intervened with a Cemented Bipolar Prosthesis. In the year 2019 he took o hip Prosthesis Review.


Assuntos
Humanos , Próteses e Implantes , Artroplastia de Quadril , Osteotomia , Dor , Fraturas Ósseas , Acetábulo
12.
Theriogenology ; 130: 62-70, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30870708

RESUMO

Glycogen content in mink uterine glandular and luminal epithelia (GE and LE) is maximal during estrus and is depleted before implantation while embryos are in diapause. Uterine glycogen synthesis in vivo is stimulated by estradiol (E2) while its mobilization is induced by progesterone (P4). Nevertheless, treatment of an immortalized mink uterine epithelial cell line (GMMe) with E2 did not affect glycogen production. Interestingly, insulin alone significantly increased synthesis of the nutrient and glycogen content in response to insulin + E2 was greater than for insulin alone. Our objectives were to determine: 1) If insulin receptor protein (INSR) is expressed by mink uterine GE and LE in vivo and if the amount differs between estrus, diapause and pregnancy; 2) if E2, P4 or insulin regulate insulin receptor gene (Insr) expression by GMMe cells, and 3) if E2 and P4 act independently to regulate glycogen metabolism by GMMe cells and/or if their effects are mediated in part through the actions of insulin. The mean (±S.E.) percent INSR content of uterine epithelia was greatest during diapause (GE: 15.65 ± 0.06, LE:16.56 ± 1.25), much less during pregnancy (GE: 2.53 ± 0.60, LE:2.25 ± 0.32) and barely detectable in estrus (GE: 0.03 ± 0.01, LE:0.02 ± 0.01). Glycogen concentrations in GMMe cells increased 10-fold in response to insulin and 20-fold with insulin + E2 when compared to controls. Expression of Insr was increased 2-fold by insulin and insulin + E2 when compared to controls and there was no difference between the two hormone treatments, indicating that E2 does not increase Insr expression in insulin-treated cells. To simulate E2-priming, cells were treated with Insulin + E2 for 24 h, followed by the same hormones + P4 for the second 24 h (Insulin + E2 → P4) which resulted in Insr and glycogen levels not different from controls. Similarly, cells treated with Insulin + P4 resulted in glycogen concentrations not different from controls. We conclude that the glycogenic actions of E2 on GMMe cells are due to increased responsiveness of the cells to insulin, but not as a result of up-regulation of the insulin receptor. Glycogen mobilization in response to P4 was the result of decreased glycogenesis and increased glycogenolysis occurring concomitantly with reduced Insr expression. Mink uterine glycogen metabolism appears to be regulated in a reproductive cycle-dependent manner in part as a result of the actions of E2 and P4 on cellular responsiveness to insulin.


Assuntos
Estradiol/farmacologia , Glicogênio/metabolismo , Insulina/farmacologia , Vison/fisiologia , Progesterona/farmacologia , Útero/fisiologia , Animais , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Estradiol/metabolismo , Feminino , Insulina/metabolismo , Progesterona/metabolismo , Útero/citologia
13.
Nanoscale ; 11(2): 762-774, 2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30566154

RESUMO

In quantum dot sensitized solar cells (QDSSC), a cascade energy level structure controlled by assembly of cadmium-chalcogenide quantum dots can remarkably improve the sunlight harvesting and charge carrier lifetime. Despite the advantages of using co-sensitizers, energy conversion efficiencies are still low. An increased understanding of the causes of the low photoconversion efficiency (PCE) will contribute to the development of a straightforward approach to improve solar cell performance by exploiting co-sensitization. Herein we discuss how an excess of cadmium causes structural disorder and defect levels impacting the PCE of QDSSC devices. Thus, outer CdS1-xSex/inner CdS QD-co-sensitized B,N,F-co-doped-TiO2 nanotubes (BNF-TNT) were prepared. Chalcogenides were deposited by the SILAR method on BNF-TNT, varying the load of CdS as the inner sensitizer, while for CdS1-xSex, five SILAR cycles were used (5-CdS1-xSex), controlling the nominal S/Se molar ratio of the ternary alloy. Cd defects named as Cd-Cd energy levels were observed during CdS sensitization. Although incorporation of outer CdS1-xSex provides a tunable band gap to achieve good band alignment for carrier separation, Cd-Cd energy levels in the sensitizers act as recombination centers, limiting the overall electron flow at the BNF-TNT/CdS/CdS1-xSex interface. A maximum PCE of 2.58% was reached under standard AM 1.5G solar illumination at 100 mW cm-2. Additional limitations of SILAR as a deposition strategy of QDs are also found to influence the PCE of QDSSC.

14.
J Biol Methods ; 4(2)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28702464

RESUMO

Ribonucleic acid (RNA) is widely used in molecular biology assays, and some of the most common assays include: northern blotting and RT-PCR gene expression analysis. RNA is generally extracted by two methods: phenol-chloroform or commercially available silica spin column kits. Phenol-chloroform extraction is generally more economical; however, it produces hazardous byproducts, and leftover chemicals in the sample that can inhibit downstream applications. Commercial kits usually have simple set ups and short preparation time; however, they can introduce a significant expense to laboratory budgets. Here we have created a method to extract RNA using generic silica columns and readily available reagents while maintaining a high yield and purity.

15.
Nanoscale ; 9(27): 9440-9446, 2017 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-28660942

RESUMO

Effective control of the interface between the metal cathode and the electron transport layer (ETL) is critical for achieving high performance p-i-n planar heterojunction perovskite solar cells (PSCs). Several organic molecules have been explored as interlayers between the silver (Ag) electrode and the ETL for the improvement in the photovoltaic conversion efficiency (PCE) of p-i-n planar PSCs. However, the role of these organic molecules in the charge transfer at the metal/ETL interface and the chemical degradation processes of PSCs has not yet been fully understood. In this work, we systematically explore the effects of the interfacial modification of the Ag/ETL interface on PSCs using rhodamine 101 as a model molecule. By the insertion of rhodamine 101 as an interlayer between Ag and fullerene derivatives (PC60BM and PC70BM) ETLs improve the PCE as well as the stability of p-i-n planar PSCs. Atomic force microscopy (AFM) characterization reveals that rhodamine passivates the defects at the PCBM layer and reduces the band bending at the PCBM surface. In consequence, charge transfer from the PCBM towards the Ag electrode is enhanced leading to an increased fill factor (FF) resulting in a PCE up to 16.6%. Moreover, rhodamine acts as a permeation barrier hindering the penetration of moisture towards the perovskite layer as well as preventing the chemical interaction of perovskite with the Ag electrode. Interestingly, the work function of the metal cathode remains more stable due to the rhodamine incorporation. Consequently, a better alignment between the quasi-Fermi level of PCBM and the Ag work function is achieved minimizing the energy barrier for charge extraction. This work contributes to reveal the relevance of proper interfacial engineering at the metal-cathode/organic-semiconductor interface.

16.
ACS Appl Mater Interfaces ; 9(14): 12348-12354, 2017 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-28350447

RESUMO

Fabrication of solution-processed perovskite solar cells (PSCs) requires the deposition of high quality films from precursor inks. Frequently, buffer layers of PSCs are formed from dispersions of metal oxide nanoparticles (NPs). Therefore, the development of trustable methods for the preparation of stable colloidal NPs dispersions is crucial. In this work, a novel approach to form very compact semiconducting buffer layers with suitable optoelectronic properties is presented through a self-functionalization process of the nanocrystalline particles by their own amorphous phase and without adding any other inorganic or organic functionalization component or surfactant. Such interconnecting amorphous phase composed by residual nitrate, hydroxide, and sodium ions, proved to be fundamental to reach stable colloidal dispersions and contribute to assemble the separate crystalline nickel oxide NPs in the final film, resulting in a very homogeneous and compact layer. A proposed mechanism behind the great stabilization of the nanoparticles is exposed. At the end, the self-functionalized nickel oxide layer exhibited high optoelectronic properties enabling perovskite p-i-n solar cells as efficient as 16.6% demonstrating the pertinence of the presented strategy to obtain high quality buffer layers processed in solution at room temperature.

17.
ACS Appl Mater Interfaces ; 9(3): 2342-2349, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28019096

RESUMO

Since the first reports of efficient organic-inorganic perovskite solar cells in 2012, an explosion of research activity has emerged around the world, which has led to a rise in the power conversion efficiencies (PCEs) to over 20%. Despite the impressive efficiency, a key area of the device which remains suboptimal is the electron extraction layer and its interface with the photoactive perovskite. Here, we implement an electron collection "bilayer" composed of a thin layer of zirconia coated with titania, sitting upon the transparent conductive oxide fluorine-doped tin oxide (FTO). With this double collection layer we have reached up to 17.9% power conversion efficiency, delivering a stabilized power output (SPO) of 17.0%, measured under simulated AM 1.5 sunlight of 100 mW cm-2 irradiance. Finally, we propose a mechanism of the charge transfer processes within the fabricated architectures in order to explain the obtained performance of the devices.

18.
Biosalud ; 15(1): 87-97, ene.-jun. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-950972

RESUMO

Introducción: La clavícula es uno de los huesos más propensos a lesiones, debido a su localización subcutánea y relativamente anterior; su manejo, ortopédico o quirúrgico, sigue siendo controvertido. Por este motivo, el objetivo que guió la revisión fue justamente identificar las tendencias actuales en cuanto al diagnóstico y al manejo de la fractura de clavícula. Materiales y Métodos: Se realizó una revisión de artículos, usando las bases de datos PubMed/Medline, ScienceDirect, Embase, Ovid, SpringerLink. Se seleccionaron 57 referencias, con base en la calidad de la evidencia presentada por las mismas. Resultados y Discusión: La elección del tratamiento más adecuado para la fractura de clavícula sigue constituyéndose en un reto para el ortopedista. El análisis se debe basar en las características individuales de cada paciente, de una cuidadosa consideración de los beneficios y en los daños relativos de cada intervención, como también en las preferencias del paciente. Para avanzar en la definición de estándares terapéuticos se requiere la realización de estudios que tengan en cuenta un mayor número de individuos especialmente en los extremos de la vida y que permitan generar un mejor nivel de evidencia.


Introduction: The clavicle is one of the bones more prone to injury because due to their subcutaneous and relative anterior position. Its management, either orthopedic or surgical, remains controversial. Therefore, the objective that guided this review was to identify current trends in the diagnosis and management of broken clavicle. Materials and Methods: a review of articles was conducted using PubMed / Medline, ScienceDirect, Embase, Ovid, and SpringerLink databases. Fifty-seven (57) references were selected based on the quality of the evidence they presented. Results and Discussion: Choosing the most appropriate treatment for broken clavicle continues to be a challenge for the orthopedist. The analysis should be based on the individual characteristics of each patient, a careful consideration of the benefits and the relative harms of each intervention, as well as patient preferences. To advance in the definition of therapeutic standards, are required the performance of studies that take into account a greater number of individuals particularly in the extremes of life, which allow generating a higher level of evidence.

19.
San Salvador; s.n; 2005. 85 p. Tab, Ilus.
Tese em Espanhol | LILACS, BISSAL | ID: biblio-1252490

RESUMO

Con el paso de los años la salud del ser humano se ha constituido en la principal causa de preocupación e interés para los científicos, investigadores y profesionales involucrados en el campo de la salud. Los estímulos intrínsecos o extrínsecos que rodean al hombre producen una variedad de estados de ánimo que pueden alterar positiva o negativamente el rendimiento del organismo lo que conlleva al desarrollo de comportamientos repetitivos no siempre conscientes pero si inadecuados. Existen diversos factores tensionales predisponentes, asociados con factores orales los cuales contribuyen a desencadenar patologías que con frecuencia afectan al sistema estomatognático; siendo en este caso el bruxismo, una de las alteraciones que afectan a mayor número de individuos en la actualidad; condición clínica que pasa inadvertida por la mayoría de personas que padecen tal situación. El bruxismo es considerado un hábito caracterizado por hiperfunción de los músculos de la masticación, que lleva al apretamiento y rechinamiento de dientes con el consiguiente desgaste y alteración de la relación oclusal y de otras áreas del sistema estomatognático, cuyas secuelas en cada uno de los componentes de dicho sistema son muy dañinas, convirtiéndose además en una de las causas primordiales de la desorganización en su totalidad de dicho sistema. Por lo tanto, es necesario que el odontólogo realice un análisis exhaustivo del problema identificando los múltiples factores que se presentan en cada individuo con el fin de realizar un diagnóstico y plan de tratamiento, acorde a las necesidades de cada paciente. Con el presente trabajo de investigación se da a conocer la cantidad de pacientes que se presentaron con bruxismo en el período de febrero a noviembre del 2002; verificando si se les dio seguimiento a los pacientes de acuerdo a lo plasmado en los expedientes mediante el diagnostico, plan de tratamiento y sus respectivos controles. De los resultados de este estudio se recomiendan acciones enfocadas a mejorar la atención de la población identificada con bruxismo y que es tratada en las clínicas odontológicas de la Universidad de El Salvador.


Over the years, human health has become the main cause of concern and interest for scientists, researchers and professionals involved in the field of health. The intrinsic or extrinsic stimuli that surround man produce a variety of moods that can positively or negatively alter the performance of the organism, which leads to the development of repetitive behaviors that are not always conscious but are inappropriate. There are various predisposing stress factors associated with oral factors which contribute to triggering pathologies that frequently affect the stomatognathic system; being in this case bruxism, one of the alterations that affect the greatest number of individuals today; clinical condition that goes unnoticed by most people who suffer from such a situation. Bruxism is considered a habit characterized by hyperfunction of the chewing muscles, which leads to clenching and grinding of teeth with the consequent wear and alteration of the occlusal relationship and other areas of the stomatognathic system, whose sequelae in each of the components of said system are very harmful, also becoming one of the primary causes of the disorganization in its entirety of said system. Therefore, it is necessary for the dentist to carry out an exhaustive analysis of the problem, identifying the multiple factors that occur in each individual in order to make a diagnosis and treatment plan, according to the needs of each patient. With this research work, the number of patients who presented with bruxism in the period from February to November 2002 is revealed; verifying if the patients were followed according to what is reflected in the records through the diagnosis, treatment plan and their respective controls. From the results of this study, actions are recommended focused on improving the care of the population identified with bruxism and that is treated in the dental clinics of the University of El Salvador.


Assuntos
Bruxismo , Patologia Bucal , Faculdades de Odontologia , Ajuste Oclusal , El Salvador , Má Oclusão
20.
Arq. gastroenterol ; 41(4): 239-244, out.-dez. 2004. tab
Artigo em Inglês | LILACS | ID: lil-401527

RESUMO

O estrato socioeconômico baixo é o maior fator de risco para a aquisição natural da infecção por Helicobacter pylori em países em desenvolvimento. As vias de transmissão são desconhecidas embora estudos sugerem transmissão pessoa-pessoa. OBJETIVO: Avaliar a soropositividade de anticorpos anti H. pylori em familiares de pacientes sintomáticos infectados comparados a de pacientes não infectados. CASUÍSTICA E MÉTODOS: Foram estudados 112 familiares de 38 pacientes encaminhados para afastar doença péptica. Os pacientes foram submetidos a exame endoscópico, sendo realizadas quatro biopsias gástricas para pesquisa de H. pylori: duas para teste rápido da urease e duas para histologia (HE/Giemsa). Foi considerado infectado por H. pylori quando ambos os exames resultaram positivos. Nos familiares foi realizada sorologia com método ELISA, utilizando-se o Kit Cobas Core II (Roche), sendo considerado resultado positivo a titulação 7U/mL. Os familiares foram divididos em três grupos: grupo I: 29 familiares de 10 pacientes com úlcera duodenal H. pylori+; grupo II: 57 familiares de 17 pacientes sem úlcera duodenal H. pylori+; grupo III: 26 familiares de 11 pacientes H. pylori-. Foi testada a associação entre grupos e positividade através de uma extensão do teste exato de Fisher (método de Montecarlo SPSS), sendo analisada a soropositividade em cada um dos membros da família: pai, mãe, irmãos e o binômio mãe/pai e para a avaliação de múltiplas variáveis utilizou-se ANOVA. RESULTADOS: Os familiares de pacientes H. pylori+ apresentaram maior soropositividade comparado com o grupo controle, 83% vs 38%, sendo maior nas mães 81% vs 18% e irmãos 76% vs 20%. A soropositividade do pai não foi estatiscamente significante, quando comparados os três grupos de pacientes: 100% vs 86% vs 70%. A soropositividade de todos os membros da família, mãe, pai e irmãos nos grupos de úlcera duodenal H. pylori+ e sem úlcera duodenal H. pylori+ foram semelhantes. CONCLUSÃO: Familiares de pacientes infectados apresentam mais infecção por H. pylori. A soropositividade foi semelhante entre os familiares dos pacientes infectados com e sem úlcera duodenal. Infecção por H. pylori é mais freqüente em mães e irmãos de pacientes infectados; ao contrário, nos pais não houve diferença estatisticamente...


Assuntos
Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticorpos Antibacterianos/sangue , Família , Gastrite/microbiologia , Infecções por Helicobacter/transmissão , Helicobacter pylori/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas , Análise de Variância , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Gastrite/diagnóstico , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/imunologia , Fatores de Risco
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