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1.
Nat Commun ; 14(1): 1041, 2023 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-36823200

RESUMEN

Vaccination against human cytomegalovirus (CMV) infection remains high priority. A recombinant form of a protein essential for CMV entry, glycoprotein B (gB), demonstrated partial protection in a clinical trial (NCT00299260) when delivered with the MF59 adjuvant. Although the antibody titre against gB correlated with protection poor neutralising responses against the 5 known antigenic domains (AD) of gB were evident. Here, we show that vaccination of CMV seronegative patients induces an antibody response against a region of gB we term AD-6. Responses to the polypeptide AD-6 are detected in >70% of vaccine recipients yet in <5% of naturally infected people. An AD-6 antibody binds to gB and to infected cells but not the virion directly. Consistent with this, the AD-6 antibody is non-neutralising but, instead, prevents cell-cell spread of CMV in vitro. The discovery of AD-6 responses has the potential to explain part of the protection mediated by gB vaccines against CMV following transplantation.


Asunto(s)
Infecciones por Citomegalovirus , Vacunas contra Citomegalovirus , Humanos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Citomegalovirus , Infecciones por Citomegalovirus/prevención & control , Vacunas contra Citomegalovirus/inmunología , Proteínas del Envoltorio Viral
2.
Braz. j. biol ; 83: 1-5, 2023. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468822

RESUMEN

The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-¹ were obtained for the essential oil and 4.36 μg mL-¹ for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-¹ for the essential oil of citronella and 86.30 μg mL-¹ for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.


O óleo essencial de citronela (Cymbopogon winterianus) possui diversas atividades biológicas, entre elas a ação repelente a insetos. Alguns estudos mostraram que os ésteres do ácido cinâmico podem ser aplicados como pesticidas naturais, inseticidas e fungicidas. Nesse contexto, o objetivo do presente trabalho foi avaliar a produção de ésteres a partir do óleo essencial de citronela com ácido cinâmico via esterificação enzimática. Além disso, foi investigada a toxicidade do óleo essencial antes e após a esterificação contra Artemia salina e a ação larvicida sobre Aedes aegypti. Os ésteres foram produzidos utilizando ácido cinâmico como agente acilante e óleo essencial de citronela (3: 1) em heptano e 15% em peso da enzima NS 88011 como biocatalisadores, a 70 ° C e 150 rpm. As taxas de conversão de cinamatos de citronelil e geranil foram 58,7 e 69,0% para NS 88011, respectivamente. Para a toxicidade sobre Artemia salina foram obtidos CL50 de 5,29 μg mL-¹ para o óleo essencial e 4,36 μg mL-¹ para os óleos esterificados com NS 88011. Na atividade inseticida contra larvas de Aedes aegypti, obteve-se CL50 de 111,84 μg mL-¹ para o óleo essencial de citronela e 86,30 μg mL-¹ para os óleos esterificados com a enzima NS 88011, indicando alta toxicidade dos ésteres. Os resultados demonstraram que as amostras avaliadas apresentam potencial de aplicação como bioinseticida.


Asunto(s)
Animales , Aedes , Artemia , Cymbopogon/enzimología , Cymbopogon/toxicidad , Ésteres/toxicidad
3.
Braz. j. biol ; 832023.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469038

RESUMEN

Abstract The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 g mL-1 were obtained for the essential oil and 4.36 g mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 g mL-1 for the essential oil of citronella and 86.30 g mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.


Resumo O óleo essencial de citronela (Cymbopogon winterianus) possui diversas atividades biológicas, entre elas a ação repelente a insetos. Alguns estudos mostraram que os ésteres do ácido cinâmico podem ser aplicados como pesticidas naturais, inseticidas e fungicidas. Nesse contexto, o objetivo do presente trabalho foi avaliar a produção de ésteres a partir do óleo essencial de citronela com ácido cinâmico via esterificação enzimática. Além disso, foi investigada a toxicidade do óleo essencial antes e após a esterificação contra Artemia salina e a ação larvicida sobre Aedes aegypti. Os ésteres foram produzidos utilizando ácido cinâmico como agente acilante e óleo essencial de citronela (3: 1) em heptano e 15% em peso da enzima NS 88011 como biocatalisadores, a 70 ° C e 150 rpm. As taxas de conversão de cinamatos de citronelil e geranil foram 58,7 e 69,0% para NS 88011, respectivamente. Para a toxicidade sobre Artemia salina foram obtidos CL50 de 5,29 g mL-1 para o óleo essencial e 4,36 g mL-1 para os óleos esterificados com NS 88011. Na atividade inseticida contra larvas de Aedes aegypti, obteve-se CL50 de 111,84 g mL-1 para o óleo essencial de citronela e 86,30 g mL-1 para os óleos esterificados com a enzima NS 88011, indicando alta toxicidade dos ésteres. Os resultados demonstraram que as amostras avaliadas apresentam potencial de aplicação como bioinseticida.

4.
Braz. j. biol ; 83: e244647, 2023. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1278527

RESUMEN

Abstract The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-1 were obtained for the essential oil and 4.36 μg mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-1 for the essential oil of citronella and 86.30 μg mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.


Resumo O óleo essencial de citronela (Cymbopogon winterianus) possui diversas atividades biológicas, entre elas a ação repelente a insetos. Alguns estudos mostraram que os ésteres do ácido cinâmico podem ser aplicados como pesticidas naturais, inseticidas e fungicidas. Nesse contexto, o objetivo do presente trabalho foi avaliar a produção de ésteres a partir do óleo essencial de citronela com ácido cinâmico via esterificação enzimática. Além disso, foi investigada a toxicidade do óleo essencial antes e após a esterificação contra Artemia salina e a ação larvicida sobre Aedes aegypti. Os ésteres foram produzidos utilizando ácido cinâmico como agente acilante e óleo essencial de citronela (3: 1) em heptano e 15% em peso da enzima NS 88011 como biocatalisadores, a 70 ° C e 150 rpm. As taxas de conversão de cinamatos de citronelil e geranil foram 58,7 e 69,0% para NS 88011, respectivamente. Para a toxicidade sobre Artemia salina foram obtidos CL50 de 5,29 μg mL-1 para o óleo essencial e 4,36 μg mL-1 para os óleos esterificados com NS 88011. Na atividade inseticida contra larvas de Aedes aegypti, obteve-se CL50 de 111,84 μg mL-1 para o óleo essencial de citronela e 86,30 μg mL-1 para os óleos esterificados com a enzima NS 88011, indicando alta toxicidade dos ésteres. Os resultados demonstraram que as amostras avaliadas apresentam potencial de aplicação como bioinseticida.


Asunto(s)
Animales , Aceites Volátiles/toxicidad , Aedes , Cymbopogon , Repelentes de Insectos , Insecticidas/toxicidad , Esterificación , Larva
5.
Braz J Biol ; 83: e244647, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34190758

RESUMEN

The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 µg mL-1 were obtained for the essential oil and 4.36 µg mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 µg mL-1 for the essential oil of citronella and 86.30 µg mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.


Asunto(s)
Aedes , Cymbopogon , Repelentes de Insectos , Insecticidas , Aceites Volátiles , Animales , Esterificación , Insecticidas/toxicidad , Larva , Aceites Volátiles/toxicidad
6.
Reprod Fertil Dev ; 33(5): 372-380, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33684338

RESUMEN

This study evaluated the effects of three maturation systems, namely invitro (MatV) and invivo (MatS) systems, as well as intrafollicular transfer of immature oocytes (IFIOT; MatT), on the accumulation of lipid droplets in bovine oocytes. Lipids were evaluated using confocal microscopy and transmission electron microscopy. The expression of genes related to lipid metabolism, namely acyl-CoA synthetase short chain family member 2 (ACSS2), ELOVL fatty acid elongase 1 (ELOVL1) and fatty acid binding protein 3 (FABP3), was quantified by quantitative polymerase chain reaction. The mean (±s.d.) area occupied by lipids in immature oocytes (13±2%) was similar to those matured invivo (MatS, 16±2%; MatT, 12±2%). However, there was a significant increase in lipids in oocytes in the MatV group (24±2%) compared with all other groups (P<0.001). In the ultrastructural evaluations, MatV oocytes also showed the highest lipid content. The expression of ELOVL1 and FABP3 was similar in the MatS and IFIOT groups. However, transcript levels of ACSS2 were lower in IFIOT than MatV oocytes. These results indicate, for the first time, that oocytes matured by IFIOT are similar to those matured invivo with regard to lipid accumulation, which indicates better quality than those matured invitro.


Asunto(s)
Bovinos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Metabolismo de los Lípidos , Oocitos/crecimiento & desarrollo , Oocitos/metabolismo , Acetato CoA Ligasa/genética , Animales , Proteína 3 de Unión a Ácidos Grasos/genética , Elongasas de Ácidos Grasos/genética , Femenino , Expresión Génica , Metabolismo de los Lípidos/genética , Oocitos/ultraestructura , Folículo Ovárico/citología
7.
Rev Port Cardiol (Engl Ed) ; 40(3): 245.e1-245.e5, 2021 Mar.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-33715921

RESUMEN

CLINICAL CASE: A 64-year-old male, with cardiovascular risk factors and previous history of bilateral carpal tunnel syndrome, presented with exertional retrosternal pain. The resting echocardiogram was unremarkable. A stress echocardiogram with dobutamine revealed hypokinesis of the inferior wall, associated with angina, followed by ventricular tachycardia. The coronary angiography revealed slow flow, a dominant right coronary artery with non-obstructive atherosclerosis and a left anterior descending artery with intermediate lesions in mid and distal segments. The invasive functional evaluation, including fractional flow reserve, thermodilution coronary flow reserve and index of microvascular resistance, led to the diagnosis of microvascular angina, treated with calcium channel blockers and transdermal nitrate, giving symptom relief. EVOLUTION: Three years later he developed complete atrioventricular block and a dual chamber pacemaker was implanted. Shortly after, the patient developed progressive symmetrical tetraparesis, associated with marked muscle atrophy, hand numbness, orthostatic hypotension and dysphagia. The neurology workup led to the diagnosis of familial amyloidotic polyneuropathy, with the Val30Met mutation in the transthyretin gene. The following year he developed congestive heart failure. The echocardiogram showed moderate concentric left ventricular hypertrophy with preserved ejection fraction. A 99mTc-DPD Scintigraphy showed significant myocardial tracer uptake, leading to a diagnosis of TTR amyloid infiltration. DISCUSSION: Patients with exertional angina and microvascular disease should be kept under close surveillance, as they may have systemic disease with cardiac involvement. Carpal tunnel syndrome, in the context of undiagnosed cardiac disease, should trigger suspicion of cardiac amyloidosis.


Asunto(s)
Enfermedad de la Arteria Coronaria , Reserva del Flujo Fraccional Miocárdico , Angina Microvascular , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico , Humanos , Masculino , Persona de Mediana Edad
8.
RSC Adv ; 11(35): 21567-21578, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35478819

RESUMEN

The potential application of all-nitrogen molecules as high energy density materials (HEDMs) has been attracting considerable scientific effort. If stable enough to be synthesized and stored, these systems may be used as a green source of energy. However, it is very difficult to obtain these structures under mild experimental conditions. Theoretical chemistry may aid in the search for polynitrogens that are more likely to have experimental usability. The barriers towards decomposition are an effective way to assess their stability, but these have not been thoroughly studied. Most of the previous effort in this direction focus on a single N x case, each employing different accuracy levels, and the decomposition of caged structures has been little explored. Here we explore the stability and decomposition of several neutral molecular polynitrogens of different sizes and shapes using a common and accurate theoretical framework in order to compare among them, search for patterns and identify potential candidates for synthesis. We focus especially on new caged geometries, and our results indicate that the prismatic ones can be expected to present higher energy densities and be very stable with respect to unimolecular decomposition. It is shown that the energy content can be clearly stratified between chain, ring, cage and prismatic cage structures.

9.
J Appl Microbiol ; 130(1): 90-99, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32640074

RESUMEN

AIMS: This work aimed to estimate the growth of Myceliophthora thermophila M.7·7 in solid-state cultivation (SSC) through quantification of N-acetyl-d-glucosamine (NAG) and enzyme activity. METHODS AND RESULTS: The fungus was cultivated in sugarcane bagasse and wheat bran. A consistent statistical analysis was done to assess the reliability of experimental data. Logistic model equation was fitted to experimental data and growth parameters were estimated. The results showed strong influence of the sample size on NAG and a minimum recommended sample size was identified. Scanning electron microscopy (SEM) was used to identify the strategy of substrate colonization. Wheat bran was attacked firstly, while sugarcane bagasse was consumed after wheat bran depletion. The biomass growth was poorly estimated by secretion kinetics of α-amylase, endoglucanase, protease and xylanase, but enzyme kinetics were important for understanding substrate colonization. CONCLUSIONS: In conclusion, the NAG concentration was strongly affected by the sample size and sampling procedure. The strategy of fungal colonization on the substrates was well characterized through SEM analysis. The colonization strategy has direct influence on the kinetic parameters of the logistic model. Myceliophthora thermophila has a well-defined dynamic of enzyme secretion to degrade the substrate, although the kinetics of enzyme secretion has shown not adequate to characterize the kinetics of fungal growth. SIGNIFICANCE AND IMPACT OF THE STUDY: The paper provides reliable growth kinetic parameters in the SSC of the cellulase producer fungus M. thermophila M.7·7, as well as a robust analysis on three indirect methods (NAG, enzymes and SEM) for estimation of fungal development.


Asunto(s)
Sordariales/crecimiento & desarrollo , Acetilglucosamina/metabolismo , Biomasa , Reactores Biológicos , Celulosa/metabolismo , Fibras de la Dieta/metabolismo , Proteínas Fúngicas/metabolismo , Cinética , Reproducibilidad de los Resultados , Saccharum/química , Sordariales/enzimología , Sordariales/metabolismo , Sordariales/ultraestructura
11.
Reprod Fertil Dev ; 32(7): 690-696, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32317093

RESUMEN

We aimed to analyse the histone acetylation status and expression profile of genes involved in histone acetylation (histone acetyltransferase 1 (HAT1), lysine acetyltransferase 2A (KAT2A), histone deacetylase 1(HDAC1), HDAC2 and HDAC3) in bovine oocytes of different competences during invitro maturation (IVM). Cumulus-oocyte complexes were recovered from two groups of follicles: minor follicles (1.0-3.0mm in diameter), classified as low competence (LC) and large follicles (6.0-8.0mm in diameter) classified as high competence (HC). Oocytes were submitted to IVM for 0, 8 and 24h and stored for analysis. Acetylation status of histone H4 on lysine K5, K6, K12 and K16 was assessed by immunohistochemistry. For gene expression, mRNA levels were determined by real-time quantitative polymerase chain reaction. All oocytes, regardless of their competence, showed a gradual decrease (P<0.05) in acetylation signals during IVM. From 0 to 8h of maturation, an increase (P<0.05) in the relative abundance of HAT1 mRNA was observed only in the HC oocytes. In this group, higher (P<0.05) mRNA levels of HDAC1 at 8h of maturation were also observed. In conclusion, in the present study, LC oocytes were shown to have adequate acetylation levels for the resumption and progression of meiosis; however, these oocytes do not have the capacity to synthesise RNA during IVM as the HC oocytes do.


Asunto(s)
Bovinos , Histona Acetiltransferasas/metabolismo , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/enzimología , Acetilación , Animales , Células del Cúmulo/fisiología , Femenino , Histona Acetiltransferasas/genética , Histonas/metabolismo , Lisina/metabolismo , Oocitos/crecimiento & desarrollo , Oogénesis/genética , Oogénesis/fisiología , ARN Mensajero/análisis
13.
Ann R Coll Surg Engl ; 101(5): 333-341, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30854865

RESUMEN

INTRODUCTION: We examine the influence of variations in provision of cardiac surgery in the UK at hospital level on patient outcomes and also to assess whether there is an inequality of access and delivery of healthcare. Cardiothoracic surgery has pioneered the reporting of surgeon-specific outcomes, which other specialties have followed. We set out to identify factors other than the individual surgeon, which can affect outcomes and enable other surgical specialties to adopt a similar model. MATERIALS AND METHODS: A retrospective analysis of prospectively collected data of patient and hospital level factors between 2013 and 2016 from 16 cardiac surgical units in the UK were analysed through the Society for Cardiothoracic Surgery of Great Britain and Ireland and the Royal College of Surgeons Research Collaborative. Patient demographic data, risks factors, postoperative complications and in-hospital mortality, as well as hospital-level factors such as number of beds and operating theatres, were collected. Correlation between outcome measures was assessed using Pearson's correlation coefficient. Associations between hospital-level factors and outcomes were assessed using univariable and multivariable regression models. RESULTS: Of 50,871 patients (60.5% of UK caseload), 25% were older than 75 years and 29% were female. There was considerable variation between units in patient comorbidities, bed distribution and staffing. All hospitals had dedicated cardiothoracic intensive care beds and consultants. Median survival was 97.9% (range 96.3-98.6%). Postoperative complications included re-sternotomy for bleeding (median 4.8%; range 3.5-6.9%) and mediastinitis (0.4%; 0.1-1.0%), transient ischaemic attack/cerebrovascular accident (1.7%; range 0.3-3.0%), haemofiltration (3.7%; range 0.8-6.8%), intra-aortic balloon pump use (3.3%; range 0.4-7.4%), tracheostomy (1.6%; range 1.3-2.6%) and laparotomy (0.3%; range 0.2-0.6%). There was variation in outcomes between hospitals. Univariable analysis showed a small number of positive associations between hospital-level factors and outcomes but none remained significant in multivariable models. CONCLUSIONS: Variations among hospital level factors exists in both delivery of, and outcomes, following cardiac surgery in the UK. However, there was no clear association between these factors and patient outcomes. This negative finding could be explained by differences in outcome definition, differences in risk factors between centres that are not captured by standard risk stratification scores or individual surgeon/team performance.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Disparidades en Atención de Salud/estadística & datos numéricos , Hospitales/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Mortalidad Hospitalaria , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Reino Unido , Adulto Joven
14.
Exp Parasitol ; 197: 36-42, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30633915

RESUMEN

Molecules from natural sources, such as essential oils, have shown activity against parasites in vitro, but have not yet been explored extensively in vivo. Anethole and carvone (10% each), encapsulated with 80% of a solid matrix, referred to as EO (encapsulated oils), were tested in vivo in 2 experiments. In Experiment 1: Lambs were artificially infected with multidrug resistant Haemonchus contortus, or left uninfected, and treated (or not) with 50 mg/kg bw (body weight) of EO in a controlled environment. Thirty-two male lambs were kept in individual cages for a period of 45 days, after which animals were evaluated for parasitological, hematological, toxicological, and nutritional parameters. After 45 days of treatment, EO at 50 mg/kg bw provided a significant (P ≤ 0.05) reduction in fecal egg count (FEC). Although FEC was reduced, animals from both treatments had similar counts of total adult worms. The low FEC was caused probably by a significant reduction (P ≤ 0.05) in both male worm size and female fecundity. Dry matter intake of uninfected controls was significantly (P ≤ 0.05) reduced, although no toxicity was observed in treated animals. Thus, in Experiment 2, conducted for five months we used an EO dose of 20 mg/kg bw. Thirty-four weaned lambs, free of parasites, were divided in two groups and kept in collective pens. One group received EO at 20 mg/kg bw mixed with concentrate for 5 months and the other was kept as a control group (CTL). Parasitological and hematological parameters as well as body weight were evaluated. In the first 2.5 months, CTL and EO groups were confined, and both presented similar clinical parameters. Then, animals were allotted to graze on contaminated pastures to acquire natural infection for the next 2.5 months. The infection was patent after 25 days and both groups had similar decreases in weight gain, increases in FEC, and decreases in blood parameters. Coprocultures from CTL and EO groups established that parasite population was 90% Haemonchus sp. We concluded that the technology of encapsulation is safe and practical to deliver to lambs at the farm level and anethole and carvone at 50 mg/kg bw caused a significant decrease in FEC and, consequently, in pasture contamination by free living stages of H. contortus. However, EO at 20 mg/kg bw was not effective to prevent or treat sheep naturally-infected with gastrointestinal nematodes.


Asunto(s)
Anisoles/uso terapéutico , Hemoncosis/veterinaria , Monoterpenos/uso terapéutico , Enfermedades de las Ovejas/tratamiento farmacológico , Enfermedades de las Ovejas/parasitología , Abomaso/parasitología , Derivados de Alilbenceno , Animales , Anisoles/administración & dosificación , Anisoles/química , Aspartato Aminotransferasas/sangre , Cápsulas , Creatinina/sangre , Monoterpenos Ciclohexánicos , Resistencia a Múltiples Medicamentos , Sinergismo Farmacológico , Ingestión de Alimentos , Recuento de Eritrocitos/veterinaria , Heces/parasitología , Femenino , Fertilidad , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Haemonchus/efectos de los fármacos , Haemonchus/crecimiento & desarrollo , Haemonchus/fisiología , Masculino , Monoterpenos/administración & dosificación , Monoterpenos/química , Recuento de Huevos de Parásitos/veterinaria , Distribución Aleatoria , Ovinos , Urea/sangre , Aumento de Peso , gamma-Glutamiltransferasa/sangre
15.
Mater Sci Eng C Mater Biol Appl ; 92: 868-874, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30184816

RESUMEN

Even though skeletal muscle cells can naturally regenerate as a response to insignificant tissue damages, more severe injuries can cause irreversible loss of muscle cells mass and/or function. Until now, cell therapies are not a good approach to treat those injuries. Biomaterials such as poly(vinylidene fluoride), PVDF, can improve muscle regeneration by presenting physical cues to muscle cells that mimic the natural regeneration environment. In this way, the ferroelectric and piezoelectric properties of PVDF offer new opportunities for skeletal muscle tissue engineering once the piezoelectricity is an electromechanical effect that can be used to provide electrical signals to the cells, upon mechanical solicitations, similar to the ones found in several body tissues. Thus, previous to dynamic experiments, it is important to determine how the surface properties of the material, both in terms of the poling state (positive or negative net surface charge) and of the morphology (films or fibers) influence myoblast differentiation. It was observed that PVDF promotes myogenic differentiation of C2C12 cells as evidenced by quantitative analysis of myotube fusion, maturation index, length, diameter and number. Charged surfaces improve the fusion of muscle cells into differentiated myotubes, as demonstrated by fusion and maturation index values higher than the control samples. Finally, the use of random and oriented ß-PVDF electrospun fibers scaffolds has revealed differences in cell morphology. Contrary to the randomly oriented fibers, oriented PVDF electrospun fibers have promoted the alignment of the cells. It is thus demonstrated that the use of this electroactive polymer represents a suitable approach for the development of electroactive microenvironments for effective muscle tissue engineering.


Asunto(s)
Materiales Biocompatibles/química , Animales , Diferenciación Celular/fisiología , Línea Celular , Proliferación Celular/fisiología , Ratones , Desarrollo de Músculos/fisiología , Fibras Musculares Esqueléticas/citología , Mioblastos/citología , Propiedades de Superficie , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
16.
Int J Cosmet Sci ; 40(4): 408-419, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30047992

RESUMEN

OBJECTIVE: Human hair is an element with unquestionable relevance in society both for women and men. Therefore, it is of great importance to develop new cosmetic products for hair care capable to restore and improve hair's characteristics. Here, we explore the potential of keratin-based particles in the protection and recovery of hair mechanical properties and thermal stability. METHODS: Keratin-based particles were obtained by high pressure homogenization (HPH) using keratin and silk fibroin. The particles were characterized regarding size, superficial charge and polydispersity index. Their safety to cells was assessed using human skin keratinocytes. Virgin and overbleached Asian hair were treated with eight keratin-based formulations. The effect of particles on hair's mechanical properties was evaluated in terms of stiffness and tensile strength. The impact of treatments in hair thermal performance was studied using differential scanning calorimetry (DSC). RESULTS: Keratin-based particles were capable to recover and/or improve the mechanical properties of virgin and overbleached hair. Virgin hair treated with K80 SF20 P particles presented an improvement in the mechanical properties of around 40%. An increase in keratin α-helix denaturation enthalpy and in surface smoothness for both types of hair was also verified after treatment. These particles demonstrated stability over time and proved to be safe when tested in human keratinocytes. CONCLUSION: The keratin-based particles here presented have the potential to be incorporated in the development of new and effective hair care cosmetic formulations.


Asunto(s)
Preparaciones para el Cabello , Cabello/efectos de los fármacos , Queratinas/administración & dosificación , Pueblo Asiatico , Rastreo Diferencial de Calorimetría , Línea Celular , Femenino , Humanos , Queratinocitos/efectos de los fármacos , Queratinas/química , Queratinas/farmacología , Masculino , Microscopía Electrónica de Transmisión de Rastreo , Estructura Secundaria de Proteína , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción
17.
N Biotechnol ; 46: 45-53, 2018 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-30012422

RESUMEN

With the lack of new chemical antibiotics and increasing pathogen resistance to those available, new alternatives are being explored. Antimicrobial peptides (AMPs) with a broad range of effects, including antibacterial, antifungal, and antiviral actions, have emerged as one of the options. They can be produced by recombinant DNA technology, but the chromatographic methods used for peptide purification are expensive and time consuming. Here, we describe the design, production, purification and assessment of the antibacterial activity of the human peptide hepcidin, using an elastin-like recombinamer as fusion partner. The recombinant protein Hep-A200 was produced in Escherichia coli and purified by a non-chromatographic procedure, exploiting the thermal properties of the A200 elastin-like recombinamer. Recombinant Hep-A200 was found to retain antibacterial activity against Gram-positive and Gram-negative species.


Asunto(s)
Antibacterianos/metabolismo , ADN Recombinante/metabolismo , Elastina/metabolismo , Hepcidinas/biosíntesis , Antibacterianos/química , Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , ADN Recombinante/química , Elastina/química , Escherichia coli/química , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Hepcidinas/química , Hepcidinas/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Propiedades de Superficie
18.
Parasitol Res ; 117(3): 705-712, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29327323

RESUMEN

Albendazole (ABZ), a benzimidazole widely used to control gastrointestinal parasites, is poorly soluble in water, resulting in variable and incomplete bioavailability. This has favored the appearance ABZ-resistant nematodes and, consequently, an increase in its clinical ineffectiveness. Among the pharmaceutical techniques developed to increase drug efficacy, cyclodextrins (CDs) and other polymers have been extensively used with water-insoluble pharmaceutical drugs to increase their solubility and availability. Our objective was to prepare ABZ formulations, including ß-cyclodextrin (ßCD) or hydroxypropyl-ß-cyclodextrin (HPßCD), associated or not to the water-soluble polymer polyvinylpyrrolidone (PVP). These formulations had their solubility and anthelmintic effect both evaluated in vitro. Also, their anthelmintic efficacy was evaluated in lambs naturally infected with gastrointestinal nematodes (GIN) through the fecal egg count (FEC) reduction test. In vitro, the complex ABZ/HPßCD had higher solubility than ABZ/ßCD. The addition of PVP to the complexes increased solubility and dissolution rates more effectively for ABZ/HPßCD than for ABZ/ßCD. In vivo, 48 lambs naturally infected with GIN were divided into six experimental groups: control, ABZ, ABZ/ßCD, ABZ/ßCD-PVP, ABZ/HPßCD, and ABZ/HPßCD-PVP. Each treated animal received 10 mg/kg of body weight (based on the ABZ dose) for three consecutive days. After 10 days of the last administered dose, treatment efficacy was calculated. The efficacy values were as follows: ABZ (70.33%), ABZ/ßCD (85.33%), ABZ/ßCD-PVP (82.86%), ABZ/HPßCD (78.37%), and ABZ/HPßCD-PVP (43.79%). In vitro, ABZ/HPßCD and ABZ/HPßCD-PVP had high solubility and dissolution rates. In vivo, although the efficacies of ABZ/ßCD, ABZ/ßCD-PVP, and ABZ/HPßCD increased slightly when compared to pure ABZ, this increase was not significant (P > 0.05).


Asunto(s)
Albendazol/farmacocinética , Antiparasitarios/farmacocinética , Ciclodextrinas/farmacocinética , Nanopartículas/química , Povidona/farmacocinética , 2-Hidroxipropil-beta-Ciclodextrina/química , 2-Hidroxipropil-beta-Ciclodextrina/farmacocinética , Albendazol/química , Animales , Antihelmínticos/química , Antihelmínticos/farmacocinética , Antiparasitarios/química , Disponibilidad Biológica , Ciclodextrinas/química , Composición de Medicamentos , Parasitosis Intestinales/tratamiento farmacológico , Parasitosis Intestinales/veterinaria , Masculino , Nematodos , Infecciones por Nematodos/tratamiento farmacológico , Infecciones por Nematodos/veterinaria , Povidona/química , Ovinos , Enfermedades de las Ovejas/tratamiento farmacológico , Enfermedades de las Ovejas/parasitología , Solubilidad , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacocinética
19.
Med Oral Patol Oral Cir Bucal ; 23(1): e65-e71, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29274162

RESUMEN

BACKGROUND: To compare the analgesic effect of anesthetic infiltration of lidocaine 2% and low-level laser therapy (LLLT) by GaAlAs into tender points of patients with orofacial pain and fibromyalgia (FM). MATERIAL AND METHODS: A randomized clinical trial was performed with adults (N=66) that were allocated into two groups (1:1): Group A received LLLT irradiation by Diode Laser GaAlAs (780nm) with expositions twice a week during six weeks and Group B was treated with anesthetic infiltration of lidocaine 2% without vasoconstrictor once a week for four weeks. The pain assessment included the Visual Analogic Scale (VAS) and tenderness to palpation. RESULTS: No dropout and adverse effect was observed during the study. The pain decreased significantly in each group after the treatment (p=0.0001, ß=1.0), even though no statistical difference was found between both treatments (p=0.46, ß= 0.82). The presence of tender points decreased after both treatments, with responsively in some types of masticatory muscles (p<0.05) except posterior temporalis muscle. The patients perception showed that both treatments were effective and a few patients reported that the treatment did not improve welfare. CONCLUSIONS: The LLLT by GaAlAs and anesthetic infiltration of lidocaine 2% were equally effective to control orofacial pain in FM individuals.


Asunto(s)
Anestesia Local , Anestésicos Locales/administración & dosificación , Dolor Facial/etiología , Dolor Facial/radioterapia , Fibromialgia/complicaciones , Láseres de Semiconductores/uso terapéutico , Lidocaína/administración & dosificación , Terapia por Luz de Baja Intensidad , Manejo del Dolor/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
Plant Biol (Stuttg) ; 20(1): 101-112, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28977737

RESUMEN

Three synchronopatric Cactaceae species, Echinopsis rhodotricha, Harrisia balansae and Praecereus saxicola, have mostly nocturnal anthesis and similar flowers, characteristics that motivated us to perform a comparative study of reproductive ecology. Reproductive phenology was sampled monthly from December 2014 to November 2015. We describe floral biology, breeding system via pollination treatments and evaluate floral visitors from focal and filming observations. Pollen grains found on moth proboscis were compared among cactus species under light microscopy. We used fluorescent dye particles to test intra- and interspecific pollen flow. These three species have extended flowering with greater intensity in the wet season, causing high overlap. They have white and hypocrateriformis flowers that open at twilight or nightfall and last about 15 h. H. balansae seems to be self-incompatible, while E. rhodotricha presented self-compatibility. P. saxicola presented self-fertility, but most of the population seems to be self-incompatible. We suggest sphingophily for the three species, but only P. saxicola was visited by Manduca rustica (Sphingidae). However, we observed pollen grains of all three species on the proboscis of moths, especially M. rustica and M. sexta. Prolonged anthesis allowed bees (herein considered as secondary pollinators) to visit flowers of E. rhodotricha and P. saxicola. It can be concluded that the studied species share nocturnal and diurnal pollinators, suggesting interspecific pollen flow, which, however, could not be detected with fluorescent dye particles. In view of the low frequency of primary pollinators, it appears that these three species have different reproductive strategies, ensuring the fruiting and production of viable seeds.


Asunto(s)
Cactaceae/fisiología , Polen/fisiología , Polinización , Adaptación Fisiológica/fisiología , Animales , Brasil , Ecología , Flores/fisiología , Mariposas Nocturnas/fisiología , Polinización/fisiología , Reproducción/fisiología , Factores de Tiempo
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