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1.
RSC Adv ; 14(15): 10199-10208, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38544942

RESUMO

This article describes the synthesis, characterization (1H NMR, 13C NMR, FT-IR, HRMS and XRD), UV-Vis absorption and fluorescence spectra, theoretical analysis, evaluation of nonlinear optical properties (NLO), thermal analysis and determination of the hemolytic capacity of the compound (E)-N-(4-(3-(benzo[d][1,3]dioxol-5-yl)acryloyl)phenyl)quinoline-3-carboxamide (5). Radiological findings showed that compound 5 crystallized in space group Pca21. Furthermore, theoretical DFT studies performed with the B3LYP and M062X functionals showed good agreement with the experimental results and provided valuable information on the molecular and electronic structure, reactivity, polarizability, and kinematic stability of the compound. Besides, compound 5 did not show any hemolytic effect on human erythrocytes and exhibited strong NLO properties. The TG and DTA thermograms of quinoline-chalcone (5) revealed a multi-step thermal decomposition process with a total mass loss of 83.2%, including water content loss. The DTA curves exhibited endothermic peaks corresponding to decomposition steps, melting point, and thermochemical transition. Additionally, exothermic peaks in the DTA thermograms align with significant mass loss, confirming the compound's melting point and water content, as validated by X-ray diffraction analysis. These results contribute to the advancement of research on compounds with NLO properties and offer a promising avenue for the development of substances potentially applicable to optical devices in the biomedical field.

2.
BMC Oral Health ; 23(1): 279, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170213

RESUMO

BACKGROUND: The death of oral keratinocytes is a crucial step in the emergence of recurrent aphthous stomatitis (RAS, also known as aphthae or aphthous ulcers). Since there are no experimental models available to research aphthous ulcers, little is understood about this process. We hypothesize that saliva can be a data bank of information that offers insights on epithelial damage. METHODS: In this case-crossover study, we assessed the salivary proteome of patients with RAS (n = 36) in the presence and absence of ulcers using discovery proteomics and bioinformatics. Additionally, we contrasted these patterns with those of healthy individuals (n = 31) who had no prior aphthous ulceration. RESULTS: Salivary proteome showed that during the ulcerative phase, controlled cell death was downregulated. Due to its ability to distinguish between individuals with and without ulcers, the ATF6B protein raises the possibility that endoplasmic reticulum (ER) stress is responsible for the damage that leads to the death of oral keratinocytes. The high abundance of TRAP1 and ERN1 matches with this biological discovery. The type of death is immunogenic, according to the functional data found in a cell death database. CONCLUSION: We identified a cellular process that can lead to the death of oral keratinocytes in the etiopathogenesis process of RAS. Future studies should be conducted to identify what is responsible for the increase in ER stress signaling that would lead to an anti-cell death response.


Assuntos
Estomatite Aftosa , Humanos , Estomatite Aftosa/metabolismo , Estudos Cross-Over , Úlcera/complicações , Proteoma , Proteínas e Peptídeos Salivares , Recidiva , Proteínas de Choque Térmico HSP90
3.
Adv Sci (Weinh) ; 10(5): e2205879, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36494090

RESUMO

Realization of remote wearable health monitoring (RWHM) technology for the flexible photodiodes is highly desirable in remote-sensing healthcare systems used in space stations, oceans, and forecasting warning, which demands high external quantum efficiency (EQE) and detectivity in NIR region. Traditional inorganic photodetectors (PDs) are mechanically rigid and expensive while the widely reported solution-processed mixed tin-lead (MSP) perovskite photodetectors (PPDs) exhibit a trade-off between EQE and detectivity in the NIR region. Herein, a novel functional passivating antioxidant (FPA) strategy has been introduced for the first time to simultaneously improve crystallization, restrain Sn2+ oxidization, and reduce defects in MSP perovskite films by multiple interactions between thiophene-2-carbohydrazide (TAH) molecules and cations/anions in MSP perovskite. The resultant solution-processed rigid mixed Sn-Pb PPD simultaneously achieves high EQE (75.4% at 840 nm), detectivity (1.8 × 1012 Jones at 840 nm), ultrafast response time (trise /tfall = 94 ns/97 ns), and improved stability. This work also highlights the demonstration of the first flexible photodiode using MSP perovskite and FPA strategy with remarkably high EQE (75% at 840 nm), and operational stability. Most importantly, the RWHM is implemented for the first time in the PIN MSP perovskite photodiodes to remotely monitor the heart rate of humans at rest and after-run conditions.

4.
Sensors (Basel) ; 22(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36502032

RESUMO

A highly sensitive and selective formaldehyde sensor was successfully fabricated using hybrid materials of nitrogen-doped double-walled carbon nanotubes (N-DWCNTs) and polyvinylpyrrolidone (PVP). Double-walled carbon nanotubes (DWCNTs) and N-DWCNTs were produced by high-vacuum chemical vapor deposition using ethanol and benzylamine, respectively. Purified DWCNTs and N-DWCNTs were dropped separately onto the sensing substrate. PVP was then dropped onto pre-dropped DWCNT and N-DWCNTs (hereafter referred to as PVP/DWCNTs and PVP/N-DWCNTs, respectively). As-fabricated sensors were used to find 1,2-dichloroethane, dichloromethane, formaldehyde and toluene vapors in parts per million (ppm) at room temperature for detection measurement. The sensor response of N-DWCNTs, PVP/DWCNTs and PVP/N-DWCNTs sensors show a high response to formaldehyde but a low response to 1,2-dichloroethane, dichloromethane and toluene. Remarkably, PVP/N-DWCNTs sensors respond sensitively and selectively towards formaldehyde vapor, which is 15 times higher than when using DWCNTs sensors. This improvement could be attributed to the synergistic effect of the polymer swelling and nitrogen-sites in the N-DWCNTs. The limit of detection (LOD) of PVP/N-DWCNTs was 15 ppm, which is 34-fold higher than when using DWCNTs with a LOD of 506 ppm. This study demonstrated the high sensitivity and selectivity for formaldehyde-sensing applications of high-performance PVP/N-DWCNTs hybrid materials.


Assuntos
Nanotubos de Carbono , Povidona , Nitrogênio , Formaldeído , Gases , Tolueno
5.
Preprint em Espanhol | SciELO Preprints | ID: pps-5009

RESUMO

Recurrent aphthous stomatitis (RAS) is the most common ulcerative disease of the oral mucosa. Currently, the therapeutic alternatives are only palliative and limited, due to a poor understanding of the etiopathogenic process. The objective of this study is to identify proteins that allow distinguishing between groups of subjects with and without Recurrent Aphthous Stomatitis, to understand the processes that control health and disease states. In this case-control study, we evaluated by means of proteomics based on mass spectrometry the saliva of healthy controls and patients with recurrent aphthous stomatitis during the presence and absence of lesions. We quantified the proteins, using the spectral counts reported by PEAKS Studio X+, and we prepared a database using SPSS statistics. We determined the differentially expressed proteins between the conditions with Perseus software using ANOVA analysis and hierarchical clustering. The salivary cyclic AMP-dependent transcription factor protein ATF-6 beta (ATF6B), stands out with a better classification profile. Hence, its presence allows us to distinguish between the presence and absence of ulcerative lesions in patients with and without recurrent aphthous stomatitis. Our analysis revealed that ATF6B is related to the endoplasmic reticulum stress response in oral keratinocytes. From a clinical perspective, we suggest that this protein is connected to several biological processes, mainly related to an anti-cell death response, determined by the stress of the endoplasmic reticulum, which could cause the damage that results in the release of this marker into the oral environment.


La estomatitis aftosa recurrente es la enfermedad más común de la mucosa oral. Actualmente las alternativas terapéuticas son sólo paliativas y limitadas, debido a la escasa comprensión del proceso etiopatogénico. El objetivo de este estudio es identificar proteínas que permitan distinguir entre grupos de sujetos con y sin estomatitis aftosa recurrente, para comprender los procesos que controlan los estados de salud y enfermedad. En este estudio de casos y controles, evaluamos mediante proteómica basada en espectrometría de masas la saliva de controles sanos y pacientes con estomatitis aftosa recurrente durante la presencia y ausencia de lesiones. Cuantificamos las proteínas, utilizando los recuentos espectrales informados por PEAKS Studio X+, y preparamos una base de datos utilizando SPSS. Determinamos las proteínas expresadas diferencialmente entre los grupos con el software Perseus mediante un análisis de ANOVA y un agrupamiento jerárquico. La proteína factor de transcripción dependiente de AMP cíclico salival ATF-6 beta (ATF6B), destaca con un mejor perfil de clasificación, por lo que su presencia permite distinguir entre la presencia y ausencia de lesiones ulcerosas en pacientes con y sin estomatitis aftosa recurrente. Nuestro análisis reveló que ATF6B está relacionada con la respuesta al estrés del retículo endoplásmico en los queratinocitos orales. Desde una perspectiva clínica, sugerimos que esta proteína está relacionada con varios procesos biológicos principalmente referentes con una respuesta anti-muerte celular, determinada por el estrés del retículo endoplásmico que podría ser la causa del daño que resulta en la liberación de este marcador al medio oral.

6.
Small Methods ; 6(8): e2200110, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35733057

RESUMO

Controlling the edge morphology and terminations of graphene nanoribbons (GNR) allows tailoring their electronic properties and boosts their application potential. One way of making such structures is encapsulating them inside single-walled carbon nanotubes. Despite the versatility of Raman spectroscopy to resolve strong spectral signals of these systems, discerning the response of long nanoribbons from that of any residual precursor remaining outside after synthesis has been so far elusive. Here, the terrylene dye is used as precursor to make long and ultra-narrow armchair-edged GNR inside nanotubes. The alignment and characteristic length of terrylene encapsulated parallel to the tube's axis facilitates the ribbon formation via polymerization, with high stability up to 750 °C when the hybrid system is kept in high vacuum. A high temperature annealing is used to remove the terrylene external molecules and a subtraction model based on the determination of a scaling factor related to the G-band response of the system is developed. This not only represents a critical step forward toward the analysis of the nanoribbon-nanotube system, but it is a study that enables unraveling the Raman signatures of the individual CH-modes (the signature of edge passivation) for GNR for the first time with unprecedented detail.

7.
Res Rep Urol ; 14: 63-70, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35257006

RESUMO

Purpose: To identify micro-RNAs (miRNAs) expression profiles in peripheral blood plasma that could play a role as potential biomarkers in patients who progressed to castration-resistant prostate cancer (CRPC). Liquid biopsy analysis of miRNAs is a fast-developing field with a considerable likelihood to predict tumor progression and metastasis by targeting genes involved in oncogenesis. Patients and Methods: Differential expression analysis of miRNAs profile in CRPC patients was performed by creating small RNA libraries of circulating miRNAs using HiSeq2500 Illumina platform. A secondary analysis of aligned reads with miRNA identification and quantification was performed using miARmaSeq. Using the Bowtie algorithm, the selected variants were compared to reference nucleotide sequence GRCh38 and miRbase. Novel miRNA sequences were structurally analyzed using mirDeep2®. Results: A total of 16 patients with CRPC were included for analysis. Identified circulating miRNAs were hsa-miR-885-3p, hsa-miR-4467, hsa-miR-4686, hsa-miR-146a-3p, hsa-miR-6514-5p. Genes identified as regulated by these miRNAs were GPR56, BDNF, CTNND1, C17orf62, and DTNA. Conclusion: We explored the miRNA expression profile in patients with CRPC, identifying five miRNAs implicated in the regulation of genes involved in prostate cancer (PCa) oncogenesis and progression. We also found miRNA 855-3p in peripheral blood for the first time, which has a critical role in tumor growth mechanisms and higher expression profile than in healthy individuals.

8.
Sci Rep ; 11(1): 15646, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34341431

RESUMO

There are currently no preventative options for recurrent aphthous stomatitis, and the only available treatments are palliative. This is partly due to a poor understanding of its etiopathogenesis. In this case-control study, we characterized the salivary proteome of patients with recurrent aphthous stomatitis in the presence and absence of lesions. Through mass spectrometry-based proteomics and bioinformatics tools, we identified that the presence of oral ulcers is associated with several specific biological processes, including the metabolic pathways of vitamin B9, B12, nitrogen, selenium, and the bacterium Neisseria meningitidis. These changes occurred only in the presence of clinically visible lesions, and there were no relevant differences between patients in anatomical regions unaffected by ulcers. Additionally, using western blot and ELISA assays, we verified that carbonic anhydrase 1 (CA1) and hemoglobin subunit beta (HBB) proteins are highly expressed during the ulcerative and remission phases of recurrent aphthous stomatitis. Our results cumulatively support saliva as an indicator of the pathophysiological changes, which occur during the clinical course of lesions. From a clinical perspective, we suggest that recurrent aphthous stomatitis is a condition triggered by temporary biological changes in people with lesions.


Assuntos
Proteoma , Saliva , Estomatite Aftosa , Vitaminas , Humanos , Recidiva
9.
Angew Chem Int Ed Engl ; 60(18): 9897-9901, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33599368

RESUMO

Carbyne is a one-dimensional allotrope of carbon consisting of a linear chain of carbon atoms bonded to each other with exceptional strength. Its outstanding mechanical, optical, and electronic properties have been theoretically predicted, but its stability has only been achieved when grown encapsulated in the hollow core of carbon nanotubes. One of the advantages of this confinement is that its properties can be controlled by the chain's length and surrounding environment. We investigated an alternative way of gaining control of its properties is using isotope labelling as tuning mechanism. The optimized liquid precursor was first chosen among several options, which can greatly enhance the yield of the confined carbyne. Then isotopic labelled liquid precursor was encapsulated for further synthesis of isotopic labelled confined carbyne. This allowed us to obtain pioneering results on isotope engineered carbyne with around 11.9 % of 13 C-labelling using 13 C-methanol as precursor.

10.
Nano Lett ; 21(2): 1096-1101, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33427471

RESUMO

Confining carbyne to a space that allows for stability and controlled reactivity is a very appealing approach to have access to materials with tunable optical and electronic properties without rival. Here, we show how controlling the diameter of single-walled carbon nanotubes opens the possibility to grow a confined carbyne with a defined and tunable band gap. The metallicity of the tubes has a minimal influence on the formation of the carbyne, whereas the diameter plays a major role in the growth. It has been found that the properties of confined carbyne can be tailored independently from its length and how these are mostly determined by its interaction with the carbon nanotube. Molecular dynamics simulations have been performed to interpret these findings. Furthermore, the choice of a single-walled carbon nanotube host has been proven crucial even to synthesize an enriched carbyne with the smallest energy gap currently reported and with remarkable homogeneity.

11.
J Phys Chem C Nanomater Interfaces ; 124(40): 22150-22157, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33072238

RESUMO

The on-surface synthesis of atomically flat N-doped graphene on oxidized copper is presented. Besides circumventing the almost standard use of metallic substrates for growth, this method allows producing graphene with ∼2.0 at % N in a substitutional configuration directly decoupled from the substrate. Angle-resolved photoemission shows a linear energy-momentum dispersion where the Dirac point lies at the Fermi level. Additionally, the N functional centers can be selectively tailored in sp2 substitutional configuration by making use of a purpose-made molecular precursor: dicyanopyrazophenanthroline (C16H6N6).

12.
Rev. esp. patol ; 53(1): 55-60, ene.-mar. 2020. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-195577

RESUMO

Se presenta el caso de una niña de 13 años de edad a quien se le diagnosticó un adenoma pleomorfo (AP) localizado en la glándula lagrimal del párpado superior izquierdo. Se realizó la escisión quirúrgica del mismo y la recuperación de la paciente fue muy satisfactoria, sin recidivas tras 2 años de seguimiento. Se lleva a cabo también una revisión de las características clínicas, radiográficas e histopatológicas de estos tumores


We present a case of a 13 year old girl with a diagnosis of Pleomorphic Adenoma (PA) located in the lacrimal gland of the left upper eyelid. The patient had a very satisfactory recovery after surgical excision of the tumor, with no recurrence after a two year follow-up. The clinical, radiological and histopathological characteristics of PAs are discussed


Assuntos
Humanos , Feminino , Adolescente , Adenoma Pleomorfo/diagnóstico , Adenoma Pleomorfo/cirurgia , Aparelho Lacrimal/patologia , Neoplasias Oculares/diagnóstico , Neoplasias Oculares/cirurgia , Resultado do Tratamento
13.
Rev Esp Patol ; 53(1): 55-60, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-31932011

RESUMO

We present a case of a 13 year old girl with a diagnosis of Pleomorphic Adenoma (PA) located in the lacrimal gland of the left upper eyelid. The patient had a very satisfactory recovery after surgical excision of the tumor, with no recurrence after a two year follow-up. The clinical, radiological and histopathological characteristics of PAs are discussed.


Assuntos
Adenoma Pleomorfo/patologia , Neoplasias Palpebrais/patologia , Aparelho Lacrimal/patologia , Adenoma Pleomorfo/diagnóstico por imagem , Adenoma Pleomorfo/etiologia , Adolescente , Neoplasias Palpebrais/diagnóstico por imagem , Neoplasias Palpebrais/etiologia , Feminino , Humanos , Aparelho Lacrimal/diagnóstico por imagem , Prognóstico
14.
ACS Omega ; 4(1): 1941-1946, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459446

RESUMO

B-doped single-walled carbon nanotubes have been synthesized from sodium tetraphenyl borate and record incorporation percentages of B heteroatoms have been found in this material as-synthesized. However, carbonaceous impurities, besides other byproducts, can still contain boron and therefore exhibit various types of competing bonding environments. To circumvent this issue, which has constantly hindered a conclusive insight to the existing bonding environments in materials alike, we have employed a purification method, which leaves ∼7% at. of B atoms of the total sample composition almost exclusively in the sp2 configuration. This record B substitutional doping, together with the identification of the competing bonding environments are revealed here unambiguously from X-ray photoelectron spectroscopy. The doping level in the purified tubes is about an order of magnitude larger than in other B-doped single-walled tubes even without purification, and brings the state-of-the-art closer to the controlled applicability of this material.

15.
Nanoscale ; 11(32): 15253-15258, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31386735

RESUMO

Three typical one-dimensional (1D)/quasi-1D nanocarbons, linear carbon chains, carbon nanotubes, and graphene nanoribbons have been proved to grow inside single-walled carbon nanotubes. This gives rise to three types of hybrid materials whose behaviour and properties compared among each other are far from being understood. After proving the successful synthesis of these nanostructured materials in recently published work, we have now been able to study their oxidation stability systematically by using resonance Raman spectroscopy. Surprisingly, the linear carbon chains, which have been theoretically predicted to be very unstable, are actually thermally stable up to 500 °C, assisted by the protection of the carbon nanotube hosts. Besides, longer linear carbon chains inside narrower CNTs are more stable than the shorter ones inside larger tubes, suggesting that the thermal stability not only depends on the length of linear carbon chains alone, but it is correlated with the confinement of the host tubes in a more complicated manner. In addition, graphene nanoribbons overall appear to be the most stable confined structures. On the other hand, peculiarities like the higher stability of the (6,5) CNT compared to that of its (6,4) counterpart allow this study to provide a solid platform for further studies on the application of these 1D nanocarbons (including true 1D linear carbon chains) under ambient conditions.

16.
PLoS One ; 14(3): e0213335, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30845198

RESUMO

In the past few years, relative frequencies of malaria parasite species in communities living in the Colombian Amazon riverside have changed, being Plasmodium vivax (61.4%) and Plasmodium malariae (43.8%) the most frequent. Given this epidemiological scenario, it is important to determine the species of anophelines involved in these parasites' transmission. This study was carried out in June 2016 in two indigenous communities living close to the tributaries of the Amazon River using protected human bait. The results of this study showed a total abundance of 1,085 mosquitos, of which 99.2% corresponded to Anopheles darlingi. Additionally, only two anopheline species were found, showing low diversity in the study areas. Molecular confirmation of some individuals was then followed by evolutionary analysis by using the COI gene. Nested PCR was used for identifying the three Plasmodium species circulating in the study areas. Of the two species collected in this study, 21.0% of the An. darlingi mosquitoes were infected with P. malariae, 21.9% with P. vivax and 10.3% with Plasmodium falciparum. It exhibited exophilic and exophagic behavior in both study areas, having marked differences regarding its abundance in each community (Tipisca first sampling 49.4%, Tipisca second sampling 39.6% and Doce de Octubre 10.9%). Interestingly, An. mattogrossensis infected by P. vivax was found for the first time in Colombia (in 50% of the four females collected). Analysis of An. darlingi COI gene diversity indicated a single population maintaining a high gene flow between the study areas. The An. darlingi behavior pattern found in both communities represents a risk factor for the region's inhabitants living/working near these sites. This highlights the need for vector control efforts such as the use of personal repellents and insecticides for use on cattle, which must be made available in order to reduce this Anopheline's abundance.


Assuntos
Anopheles/parasitologia , Malária/transmissão , Mosquitos Vetores/parasitologia , Plasmodium malariae/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Animais , Anopheles/classificação , Anopheles/fisiologia , Colômbia/epidemiologia , Feminino , Humanos , Malária/epidemiologia , Malária/parasitologia , Mosquitos Vetores/classificação , Mosquitos Vetores/fisiologia , Plasmodium malariae/genética , Plasmodium vivax/genética , Densidade Demográfica , Especificidade da Espécie
17.
Nanoscale ; 10(45): 21254-21261, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30418461

RESUMO

Double-walled carbon nanotubes (DWCNTs) combined the advantages of multi-walled (MW-) and single-walled (SW-) CNTs can be obtained by transforming the precursors (e.g. fullerene, ferrocene) into thin inner CNTs inside SWCNTs as templates. However, this method is limited since the DWCNT yield is strongly influenced by the filling efficiency (depending on the type of the filled molecules), opening and cutting the SWCNTs, and the diameter of the host SWCNTs. Therefore, it cannot be applied to all types of SWCNT templates. Here we show a universal route to synthesize ultra-thin DWCNTs via making SWCNTs stable at high temperature in vacuum. This method applies to different types of SWCNTs including metallicity-sorted ones without using any precursors since the carbon sources were from the reconstructed SWCNTs and the residue carbons. The resulting DWCNTs are with high quality and the yield of inner tubes is comparable to/higher than that of the DWCNTs made from the transformation of ferrocene/fullerene peapods.

18.
Front Genet ; 9: 372, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30250483

RESUMO

The RBSA protein is encoded by a gene described in Plasmodium species having tropism for reticulocytes. Since this protein is antigenic in natural infections and can bind to target cells, it has been proposed as a potential candidate for an anti-Plasmodium vivax vaccine. However, genetic diversity (a challenge which must be overcome for ensuring fully effective vaccine design) has not been described at this locus. Likewise, the minimum regions mediating specific parasite-host interaction have not been determined. This is why the rbsa gene's evolutionary history is being here described, as well as the P. vivax rbsa (pvrbsa) genetic diversity and the specific regions mediating parasite adhesion to reticulocytes. Unlike what has previously been reported, rbsa was also present in several parasite species belonging to the monkey-malaria clade; paralogs were also found in Plasmodium parasites invading reticulocytes. The pvrbsa locus had less diversity than other merozoite surface proteins where natural selection and recombination were the main evolutionary forces involved in causing the observed polymorphism. The N-terminal end (PvRBSA-A) was conserved and under functional constraint; consequently, it was expressed as recombinant protein for binding assays. This protein fragment bound to reticulocytes whilst the C-terminus, included in recombinant PvRBSA-B (which was not under functional constraint), did not. Interestingly, two PvRBSA-A-derived peptides were able to inhibit protein binding to reticulocytes. Specific conserved and functionally important peptides within PvRBSA-A could thus be considered when designing a fully-effective vaccine against P. vivax.

19.
ACS Nano ; 12(8): 8477-8484, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30085656

RESUMO

Linear carbon chains (LCCs) have been shown to grow inside double-walled carbon nanotubes (DWCNTs), but isolating them from this hosting material represents one of the most challenging tasks toward applications. Herein we report the extraction and separation of LCCs inside single-walled carbon nanotubes (LCCs@SWCNTs) extracted from a double-walled host LCCs@DWCNTs by applying a combined tip-ultrasonic and density gradient ultracentrifugation (DGU) process. High-resolution transmission electron microscopy, optical absorption, and Raman spectroscopy show that not only short LCCs but clearly long LCCs (LLCCs) can be extracted and separated from the host. Moreover, the LLCCs can even be condensed by DGU. The Raman spectral frequency of LCCs remains almost unchanged regardless of the presence of the outer tube of the DWCNTs. This suggests that the major importance of the outer tubes is making the whole synthesis viable. We have also been able to observe the interaction between the LCCs and the inner tubes of DWCNTs, playing a major role in modifying the optical properties of LCCs. Our extraction method suggests the possibility toward the complete isolation of LCCs from CNTs.

20.
Sci Rep ; 8(1): 5543, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29615693

RESUMO

Malaria outbreaks have been reported in recent years in the Colombian Amazon region, malaria has been re-emerging in areas where it was previously controlled. Information from malaria transmission networks and knowledge about the population characteristics influencing the dispersal of parasite species is limited. This study aimed to determine the distribution patterns of Plasmodium vivax, P. malariae and P. falciparum single and mixed infections, as well as the significant socio-spatial groupings relating to the appearance of such infections. An active search in 57 localities resulted in 2,106 symptomatic patients being enrolled. Parasitaemia levels were assessed by optical microscopy, and parasites were detected by PCR. The association between mixed infections (in 43.2% of the population) and socio-spatial factors was modelled using logistic regression and multiple correspondence analyses. P. vivax occurred most frequently (71.0%), followed by P. malariae (43.2%), in all localities. The results suggest that a parasite density-dependent regulation model (with fever playing a central role) was appropriate for modelling the frequency of mixed species infections in this population. This study highlights the under-reporting of Plasmodium spp. mixed infections in the malaria-endemic area of the Colombian Amazon region and the association between causative and environmental factors in such areas.


Assuntos
Coinfecção/epidemiologia , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Parasitemia/epidemiologia , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Adolescente , Adulto , Criança , Pré-Escolar , Coinfecção/parasitologia , Colômbia/epidemiologia , Feminino , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Parasitemia/parasitologia , Prevalência , População Rural , Adulto Jovem
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