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1.
Viruses ; 16(4)2024 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-38675917

RESUMEN

The incidence of chikungunya has dramatically surged worldwide in recent decades, imposing an expanding burden on public health. In recent years, South America, particularly Brazil, has experienced outbreaks that have ravaged populations following the rapid dissemination of the chikungunya virus (CHIKV), which was first detected in 2014. The primary vector for CHIKV transmission is the urban mosquito species Aedes aegypti, which is highly prevalent throughout Brazil. However, the impact of the locally circulating CHIKV genotypes and specific combinations of local mosquito populations on vector competence remains unexplored. Here, we experimentally analyzed and compared the infectivity and transmissibility of the CHIKV-ECSA lineage recently isolated in Brazil among four Ae. aegypti populations collected from different regions of the country. When exposed to CHIKV-infected AG129 mice for blood feeding, all the mosquito populations displayed high infection rates and dissemination efficiency. Furthermore, we observed that all the populations were highly efficient in transmitting CHIKV to a vertebrate host (naïve AG129 mice) as early as eight days post-infection. These results demonstrate the high capacity of Brazilian Ae. aegypti populations to transmit the locally circulating CHIKV-ECSA lineage. This observation could help to explain the high prevalence of the CHIKV-ECSA lineage over the Asian lineage, which was also detected in Brazil in 2014. However, further studies comparing both lineages are necessary to gain a better understanding of the vector's importance in the epidemiology of CHIKV in the Americas.


Asunto(s)
Aedes , Fiebre Chikungunya , Virus Chikungunya , Mosquitos Vectores , Animales , Aedes/virología , Virus Chikungunya/genética , Virus Chikungunya/clasificación , Virus Chikungunya/fisiología , Virus Chikungunya/aislamiento & purificación , Brasil/epidemiología , Fiebre Chikungunya/transmisión , Fiebre Chikungunya/virología , Fiebre Chikungunya/epidemiología , Ratones , Mosquitos Vectores/virología , Genotipo , Femenino , Filogenia
2.
bioRxiv ; 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37961153

RESUMEN

The global incidence of chikungunya has surged in recent decades, with South America, particularly Brazil, experiencing devastating outbreaks. The primary vector for transmitting CHIKV in urban areas is the mosquito species Aedes aegypti, which is very abundant in Brazil. However, little is known about the impact of locally circulating CHIKV genotypes and specific combinations of mosquito populations on vector competence. In this study, we analyzed and compared the infectivity and transmissibility of a recently isolated CHIKV-ECSA lineage from Brazil among four Ae. aegypti populations collected from different regions of the country. When exposed to CHIKV-infected mice for blood feeding, all mosquito populations showed high infection rates and dissemination efficiency. Moreover, using a mouse model to assess transmission rates in a manner that better mirrors natural cycles, we observed that these populations exhibit highly efficient transmission rates of CHIKV-ECSA. Our findings underscore the robust capability of Brazilian Ae. aegypti populations to transmit the locally circulating CHIKV-ECSA lineage, potentially explaining its higher prevalence compared to the Asian lineage also introduced in Brazil.

3.
ACS Appl Mater Interfaces ; 15(15): 18694-18706, 2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37014991

RESUMEN

Acute myocardial infarction (AMI) is the main cause of death worldwide, and the time of diagnosis is decisive for the effectiveness of the treatment of patients with AMI. Creatine kinase-myocardial band (CK-MB) has a predominance and high affinity with myocardial tissue, making it considered one of the main biomarkers for the diagnosis of AMI. In this work, we report a novel biodegradable composite material based on a polymer blend of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and Poly(butylene adipate-co-terephthalate) (PHBV:Ecoflex) and graphite microparticles for sensitive and selective electrochemical detection of CK-MB. The morphological and physicochemical characterizations of the thermoplastic composite material revealed a homogeneous and synergistic distribution of the graphite microparticles through the blend structure, providing low defects and high electrical conductivity with high electron transfer kinetics (k0 = 3.54 × 10-3 cm s-1) features with adequate flexibility for point-of-care applications. The portable and disposable devices were applied to detect CK-MB using the electrochemical impedance spectroscopy (EIS) technique in a relevant clinical concentration ranging from 5.0 ng mL-1 to 100.0 ng mL-1 and presented a limit of detection of 0.26 ng mL-1 CK-MB. The selectivity of the sensor was confirmed by testing the potential interference of major biomolecules found in biofluids and other relevant macromolecules. The accuracy and robustness were assessed by addition and recovery protocol in urine and saliva samples without sample pretreatment and demonstrated the potential of our method for rapid and decentralized tests of AMI. In addition, the study of the thermal, biological, and photodegradation of the devices after being used was also carried out, aiming at the disposal of the material more sustainably.


Asunto(s)
Grafito , Infarto del Miocardio , Humanos , Creatina Quinasa , Sensibilidad y Especificidad , Sistemas de Atención de Punto , Infarto del Miocardio/diagnóstico , Biomarcadores , Electrodos
4.
Birth Defects Res ; 114(19): 1291-1297, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-35574732

RESUMEN

BACKGROUND: To reveal the complex etiology of gastroschisis through two independent cases. CASES: Case 1 involves gastroschisis recurrence in a consanguineous marriage, and Case 2 concerns a fetus with gastroschisis whose mother had undergone gastroplasty. Methylation array was carried out in both cases (two fetuses with gastroschisis, their two mothers, one father from the consanguineous marriage), and in 16 controls (fetuses and their respective mothers). CONCLUSION: The two cases presented different noninherited methylation profiles.


Asunto(s)
Gastrosquisis , Femenino , Humanos , Feto , Masculino , Metilación de ADN
5.
J Biomater Sci Polym Ed ; 33(7): 900-945, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34962857

RESUMEN

The development of materials based on thermoplastic starch (TPS) is an excellent alternative to replace or reduce the use of petroleum-derived polymers. The abundance, renewable origin, biodegradability, biocompatibility, and low cost of starch are among the advantages related to the application of TPS compared to other thermoplastic biopolymers. However, through the literature review, it was possible to observe the need to improve some properties, to allow TPS to replace commonly used polyolefins. The studies reviewed achieved these modifications were achieved by using plasticizers, adjusting processing conditions, and incorporating fillers. In this sense, the addition of nanofillers proved to be the main modification strategy due to the large number of available nanofillers and the low charge concentration required for such improvement. The improvement can be seen in thermal, mechanical, electrical, optical, magnetic, antimicrobial, barrier, biocompatibility, cytotoxicity, solubility, and swelling properties. These modification strategies, the reviewed studies described the development of a wide range of materials. These are products with great potential for targeting different applications. Thus, this review addresses a wide range of essential aspects in developing of this type of nanocomposite. Covering from starch sources, processing routes, characterization methods, the properties of the obtained nanocomposites, to the various applications. Therefore, this review will provide an overview for everyone interested in working with TPS nanocomposites. Through a comprehensive review of the subject, which in most studies is done in a way directed to a specific area of study.


Asunto(s)
Nanocompuestos , Almidón , Plastificantes , Polímeros , Resistencia a la Tracción
7.
Int J Biol Macromol ; 184: 863-873, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34181999

RESUMEN

Thermoplastic starch (TPS) is a widely studied biopolymer as an alternative to the use of conventional polymers. In this sense, the incorporation of fillers or reinforcements coming preferably from other substances of natural origin, can be an alternative to try to improve some mechanical and thermal properties of starch polymers. Thus, Kraft Lignin (KL), can be an excellent filler to be incorporated, since it presents mechanical and thermal properties and reduces the cost and weight of the final compounds. TPS films were prepared by casting using dimethyl sulfoxide (DMSO) as solvent and additives with 2, 4 and 8% KL. Characterization of TPS films and compositions with KL were carried out by Fourier-Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscope (SEM), Thermogravimetric Analysis (TGA), Dynamic Thermomechanical Analysis (DMTA), tensile testing and contact angle. Samples were also analyzed for biodegradation and for the ability to remove contaminants in water, Metil Orange (MO), by Ultraviolet-Visible Spectroscopy (UV-Vis). The FT-IR spectra of the films showed bands typical of functional groups derived from starch and lignin, with the intensity of these bands varying among the samples studied. Micrographs revealed slightly different morphologies among the films, but all showed irregular shapes with structures that appeared as plots. Increasing the percentage of KL led to an increase in contact angle values, showing a more hydrophobic behavior. In the TGA analysis, it was possible to observe a change in the main degradation event of the films for lower temperatures, especially of TPS - 4 and 8% KL compared to the TPS film. Films with KL had the peak of maximum degradation shifted to temperatures below the starch film, where the decrease in intensity of the main peak in the TPS - 4% KL and TPS - 8% KL samples demonstrates that there was less mass loss in the event. There was also in the percentage of residue as the addition of KL was increased The DMTA analyses allowed for the conclusion that presence of KL in TPS film allowed for an increase in its energy storage property, and that the loss modulus followed a decreasing order of storage modulus values to TPS - 8% KL from TPS. For the tensile strength property only TPS - 4% KL has significant improvement, and the elongation at break showed an increase for TPS - 4 and 8% KL compared to TPS. Samples showed a continuous and progressive biodegradation process, being completely biodegraded within 10 days. The monitoring of the ability to remove contaminants from water by UV-Vis, also showed promising results of compounds for this application. The best results were obtained, in most tests, for the TPS- 4% KL films.


Asunto(s)
Lignina/química , Almidón/química , Calor , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Termogravimetría , Agua/química , Difracción de Rayos X
8.
Saudi J Kidney Dis Transpl ; 31(3): 604-613, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32655047

RESUMEN

Reducing dietary sodium has the potential to benefit patients with chronic kidney disease on hemodialysis (HD). This study was aimed to evaluate the effects of dietary counseling on sodium restriction and its relationship with clinical, dietary, and quality of life parameters in patients on HD treatment. This study was designed as a randomized clinical trial. The study included 87 patients on HD, divided into intervention (n = 47) and control (n = 40) groups. Anthropometric, clinical, sodium intake, and quality of life data were evaluated in both groups at four-time points: baseline (T0), 90 days (T3), 180 days (T6), and 365 days (T12). The intervention group received dietary counseling at the beginning and throughout the study. There were no between-group differences regarding anthropometric, clinical, and quality of life data at any of the time points. The mean age was 59 ± 14 years, and most of the patients were men (61%) and had hypertension (90%). Total sodium (g) and processed meat (mg sodium) intake significantly decreased in both groups [intervention: T0 = 3.5 (2.3-4.7); T12 = 2.0 (0.7-2.5); P <0.0001; control: T0 = 3 (1.5-4.9); T12 = 2.0 (0.8-3.3); P = 0.001; and intervention: T0 = 78 (25-196); T12 = 21 (0-78); P = 0.003; control: T0 = 97 (31-406); T12 = 44 (0-152); P = 0.004, respectively] . There was a significant decrease in the consumption of packaged seasonings (mg sodium) [T0 = 130 (0-854); T12 = 0 (0-0); P = 0.015] and instant noodles [T0 = 19 (0-91); T12 = 0 (0-0); P = 0.017] in the intervention group. Dietary counseling was effective in changing dietary habits. In both groups, there was a reduction in total sodium intake, which was greater in the intervention group. Moreover, a decrease in the intake of salty foods, such as packaged seasonings and instant noodles, was only observed in the intervention group.


Asunto(s)
Consejo , Educación en Salud , Diálisis Renal , Insuficiencia Renal Crónica/terapia , Sodio en la Dieta , Adulto , Anciano , Dieta Hiposódica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida
9.
Case Rep Oncol ; 10(1): 161-168, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28413392

RESUMEN

Neurofibromatosis type 1 (NF1) and AIDS are risk factors for the development of malignant neoplasms, including hematological malignancies, such as non-Hodgkin lymphoma. NF1 is an autosomal dominant disease that primarily manifests as café-au-lait spots, dermal neurofibromas, axillary and/or inguinal ephelides or freckles, plexiform neurofibromas, Lisch nodules, and bone deformities. In this report, we present a 38-year-old female patient with NF1 from childhood and AIDS who developed peripheral T-cell lymphoma with good response to chemotherapeutic treatment.

10.
Health Educ Res ; 31(5): 639-52, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27473571

RESUMEN

Information for patients provided by the pharmacist is reflected in adhesion to treatment, clinical results and patient quality of life. The objective of this study was to assess an asthma self-management model for rational medicine use. This was a randomized controlled trial with 60 asthmatic patients assigned to attend five modules presented by a pharmacist (intervention group) and 59 patients in the control group. Data collection was performed before and after this 4-month intervention and included an evaluation of asthma knowledge, lifestyle, inhaler techniques, adhesion to treatment, pulmonary function and quality of life. An economic viability analysis was also performed. The intervention group obtained an increase in asthma knowledge scores of 58.3-79.5% (P < 0.001). In this group, there was also an increase in the number of individuals who practiced physical exercise (36-43%), in the number of correct replies regarding the use of inhalers, in the percentage of adherent patients, and in quality of life scores for all domains. We concluded that this asthma self-management model was effective in improving the quality of life of asthma patients.


Asunto(s)
Asma/terapia , Calidad de Vida , Automanejo/métodos , Ejercicio Físico/fisiología , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad
11.
Braz Dent J ; 23(4): 422-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23207860

RESUMEN

Peri-implant inflammation contributes for loss of secondary stability of orthodontic mini-implants. The investigation of microbial colonization in this area would benefit its control, and consequently favor the long-term success of mini-implants. Therefore, the aim of this study was to determine the establishment and the evolution of microbial colonization process in orthodontic mini-implants for 3 months, since the time of their installation. One-hundred and fifty samples collected from 15 mini-implants were investigated from baseline up to 3 months. The biological material was obtained from peri-implant area using paper points. Nonspecific, Streptococcus spp, Lactobacillus casei and Candida spp colonizations were analyzed by cell growth methods. Porphyromonas gingivalis colonization was observed by 16S rDNA-directed polymerase chain reaction. Data from cell growth were submitted to the Wilcoxon sign rank test and results from molecular analysis were presented in a descriptive way. There was no significant difference in the microbial colonization among the examined time intervals, except for Streptococcus spp, between baseline and 24 h, which characterized the initial colonization in this time interval. Lactobacillus casei and Candida spp colonizations were insignificant. No Porphyromonas gingivalis was detected among the analyzed samples. The microbial colonization of mini-implants did not significantly change during the study. However, it should be monitored by orthodontists, since it is an important factor for mini-implants success.


Asunto(s)
Bacterias/crecimiento & desarrollo , Implantes Dentales/microbiología , Métodos de Anclaje en Ortodoncia/instrumentación , Adolescente , Aleaciones , Antiinfecciosos Locales/uso terapéutico , Bacterias/clasificación , Carga Bacteriana , Técnicas Bacteriológicas , Candida/crecimiento & desarrollo , Clorhexidina/uso terapéutico , Aleaciones Dentales/química , Femenino , Estudios de Seguimiento , Humanos , Lacticaseibacillus casei/crecimiento & desarrollo , Masculino , Antisépticos Bucales/uso terapéutico , Higiene Bucal/educación , Reacción en Cadena de la Polimerasa , Porphyromonas gingivalis/clasificación , Porphyromonas gingivalis/crecimiento & desarrollo , ARN Bacteriano/análisis , ARN Ribosómico 16S/análisis , Streptococcus/clasificación , Streptococcus/crecimiento & desarrollo , Titanio/química , Técnicas de Movimiento Dental/instrumentación , Cepillado Dental/métodos , Adulto Joven
12.
Am J Orthod Dentofacial Orthop ; 141(2): 242-4, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22284292

RESUMEN

During orthodontic treatment with miniscrews, complications such as aphthous ulceration, soft-tissue coverage of the miniscrew head, soft-tissue inflammation, infection, and peri-implantitis can occur. Good hygiene can prevent inflammation by infection but does not prevent traumatic oral mucosal lesions at the buccal mucosa. The purpose of this article was to describe the use of a physical barrier--a light-cured temporary filling material--to cover the miniscrew head and prevent soft-tissue trauma.


Asunto(s)
Implantes Dentales , Mucosa Bucal/lesiones , Métodos de Anclaje en Ortodoncia/instrumentación , Diseño de Aparato Ortodóncico , Materiales Biocompatibles Revestidos/química , Materiales Dentales/química , Humanos , Frenillo Labial/lesiones , Úlceras Bucales/prevención & control , Estomatitis/prevención & control , Propiedades de Superficie
13.
Acta odontol. venez ; 50(2)2012. tab
Artículo en Español | LILACS | ID: lil-676713

RESUMEN

El objetivo del artículo fue buscar evidencias científicas que respalden la utilización del ozono para el tratamiento de la caries dental. Para lograr tal objetivo se debe responder la pregunta: "¿La aplicación del ozono puede paralizar o revertir el proceso de la caries dental?" Se realizó una revisión sistemática de la literatura en la cual se incluyeron artículos completos publicados en periódicos indexados en por lo menos una base de datos electrónica. Los criterios de inclusión empleados fueron el idioma (inglés, portugués, español e italiano) y el modelo de estudio (ensayo clínico y de revisión sistemática). Se analizo los artículos observándose el tipo de estudio, la caracterización de los sujetos, el tipo de intervención, el periodo de acompañamiento y los resultados. Se incluyo en esta revisión 8 artículos científicos, entre ellos 3 revisiones sistemáticas y 5 ensayos clínicos. Se consideró 3 referencias de alta evidencia científica, 2 de moderada y 3 de baja evidencia. Aún no existen evidencias científicas sólidas para justificar la utilización del ozono para el tratamiento de la caries. Deben desarrollarse nuevos estudios clínicos randomizados para incluir o no definitivamente el ozono en el arsenal terapéutico del tratamiento de la caries.


The purpose of this study was search for scientific evidences that support the use of ozone for the treatment of dental caries. The question is: "Can ozone stop the carious lesion?" A systematic review of the literature, including complete articles published by journals indexed by at least one data base which permit online access to references. The inclusion criteria were (1) language (English, Portuguese, Spanish and Italian), and (2) study model (clinical trial and systematic review). The articles were analyzed with focus on study types, subject characterization, type of intervention, follow-up and results. Sixty-five references were excluded and 8 included, that were 3 systematic reviews and 5 clinical trials. With regard to scientific evidence, 3 were considered high, 2 moderate, and 3 low. There are not yet solid scientific evidences to justify the use of ozone to treat dental caries. New randomized clinical trials should be carried out to definitively include ozone in or exclude it from the therapeutic arsenal for caries treatment.


Asunto(s)
Caries Dental/terapia , Caries Dental , Ozono/administración & dosificación , Ozono/uso terapéutico , Terapéutica
14.
Rev. odonto ciênc ; 23(1): 67-71, jan.-mar. 2008. tab
Artículo en Portugués | LILACS, BBO - Odontología | ID: lil-487787

RESUMEN

Objetivo: Verificar a influência do tempo de polimerização de resinas compostas na absorção de água por diferentes resinas compostas. Metodologia: As resinas multiuso Z250®, compactável P60® e de micropartículas A110® foram utilizadas para a confecção de corpos-de-prova (n=5 por grupo) de acordo com o tempo de fotopolimerização (o indicado pelo fabricante, a metade e o dobro do tempo preconizado). A quantidade de água absorvida pelos espécimes foi medida pela variação da massa dos mesmos, que foram pesados imediatamente após sua confecção, a cada 24h por 10 dias, e após 15 e 30 dias. Os dados foram analisados por ANOVA e teste de Tukey. Resultados: A absorção de água das resinas compostas foi diferente quando o tempo de polimerização foi alterado. A resina de micropartículas teve o melhor comportamento perante a mudança no tempo de fotopolimerização, enquanto que a resina de multiuso foi a que mais absorveu água quando o tempo foi alterado para menos (P < 0,05). Conclusão: O tempo de polimerização sugerido pelo fabricante deve ser respeitado para assegurar a manutenção das propriedades desses materiais, independentemente do tipo de resina utilizado.


Purpose: The aim of this study was to evaluate the influence of polymerization time of different composites on water sorption. Methods: Composites used in this study were: multipurpose Z-250, packable P-60, and microfilled A-110. The specimens (n=5 per group) were build up using a cylinder Teflon matrix and grouped according composite type and polymerization time (one group as indicated by the manufacturer, half time, and double time). Water sorption was measured by specimen mass variation immediately after building up and after 24 hours for 10 days, and in 15 and 30 days. Results: Water sorption of composites was modified as a function of polymerization time. The microfilled composite showed the best performance while the multipurpose composite had the largest water sorption values when polymerization time decreased (P < 0.05). Conclusion: The results suggest that the polymerization time indicated by the manufacturer should be followed to assure good material properties independently from composite type.


Asunto(s)
Humanos , Luz , Resinas Compuestas , Absorción , Agua
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