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1.
Plant Cell Physiol ; 65(1): 107-119, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-37874980

RESUMO

Symbioses with beneficial microbes are widespread in plants, but these relationships must balance the energy invested by the plants with the nutrients acquired. Symbiosis with arbuscular mycorrhizal (AM) fungi occurs throughout land plants, but our understanding of the genes and signals that regulate colonization levels is limited, especially in non-legumes. Here, we demonstrate that in tomato, two CLV3/EMBRYO-SURROUNDING REGION (CLE) peptides, SlCLE10 and SlCLE11, act to suppress AM colonization of roots. Mutant studies and overexpression via hairy transformation indicate that SlCLE11 acts locally in the root to limit AM colonization. Indeed, SlCLE11 expression is strongly induced in AM-colonized roots, but SlCLE11 is not required for phosphate suppression of AM colonization. SlCLE11 requires the FIN gene that encodes an enzyme required for CLE peptide arabinosylation to suppress mycorrhizal colonization. However, SlCLE11 suppression of AM does not require two CLE receptors with roles in regulating AM colonization, SlFAB (CLAVATA1 ortholog) or SlCLV2. Indeed, multiple parallel pathways appear to suppress mycorrhizal colonization in tomato, as double mutant studies indicate that SlCLV2 and FIN have an additive influence on mycorrhizal colonization. SlCLE10 appears to play a more minor or redundant role, as cle10 mutants did not influence intraradical AM colonization. However, the fact that cle10 mutants had an elevated number of hyphopodia and that ectopic overexpression of SlCLE10 did suppress mycorrhizal colonization suggests that SlCLE10 may also play a role in suppressing AM colonization. Our findings show that CLE peptides regulate AM colonization in tomato and at least SlCLE11 likely requires arabinosylation for activity.


Assuntos
Micorrizas , Solanum lycopersicum , Micorrizas/fisiologia , Solanum lycopersicum/genética , Raízes de Plantas/metabolismo , Simbiose/genética , Peptídeos/metabolismo
2.
J Exp Bot ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38726891

RESUMO

The REQUIRED FOR ARBUSCULAR MYCORRHIZATION1 (RAM1) transcription factor from the GRAS family is well-known by its role as a master regulator of the arbuscular mycorrhizal (AM) symbiosis in dicot and monocot species, being essential in the transcriptional reprograming for the development and functionality of the arbuscules. In tomato, SlGRAS27 is the putative ortholog of RAM1 (here named SlRAM1), but has not yet been characterized. A reduced colonization of the root and an impaired arbuscule formation were observed in the SlRAM1 silenced plants, confirming the functional conservation of the RAM1 ortholog in tomato . However, unexpectedly, SlRAM1 overexpressing (UBIL:SlRAM1) plants also showed a decreased mycorrhizal colonization. Analysis of non-mycorrhizal UBIL:SlRAM1 roots revealed an overall regulation of AM-related genes and a reduction of strigolactone biosynthesis. Moreover, the external application of the strigolactone analogue GR244DO almost completely reversed the negative effects of SlRAM1 overexpression on the frequency of mycorrhization. However, it only partially recovered the pattern of arbuscule distribution observed in control plants. Our results strongly suggest that SlRAM1 has a dual regulatory role during mycorrhization and, apart from its recognized action as a positive regulator of arbuscule development, SlRAM1 is also involved in different mechanisms for the negative regulation of mycorrhization, including the repression of strigolactone biosynthesis.

3.
Sensors (Basel) ; 23(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37112439

RESUMO

Graphene-based materials have been increasingly incorporated to optical fiber plasmonic sensors due to the peculiar physical and chemical properties of these materials (hardness and flexibility, high electrical and thermal conductivity, and very good adsorption for many substances, etc.). In this paper, we theoretically and experimentally showed how the addition of graphene oxide (GO) to optical fiber refractometers permits the development of surface plasmon resonance (SPR) sensors with very good characteristics. We used doubly deposited uniform-waist tapered optical fibers (DLUWTs) as supporting structures because of their already proven good performance. The presence of GO as an effective third layer is useful to tune the wavelength of the resonances. In addition, the sensitivity was improved. We depict the procedures for the production of the devices and characterize the GO+DLUWTs produced in this way. We also showed how the experimental results are in agreement with the theoretical predictions and used these to estimate the thickness of deposited GO. Finally, we compared the performance of our sensors with other ones that have been recently reported, showing that our results are among the best reported. Using GO as the medium in contact with the analyte, in addition to the good overall performance of devices, permit consideration of this option as an interesting possibility for the future development of SPR-based fiber sensors.

4.
Molecules ; 28(18)2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37764323

RESUMO

In recent years, the determination of the antioxidant and antibacterial activity of essential oils in wild plants, such as Mexican oregano (Lippia graveolens Kunth), has become increasingly important. The objective was to compare the antioxidant and antibacterial activity of Mexican oregano essential oil obtained from plants occurring naturally in semiarid areas (Wild1 and Wild2), and those cultivated in the field (CField) and greenhouse (CGreenhouse) in northern Mexico. The Mexican oregano essential oil extraction was performed using the hydrodistillation method, the antioxidant activity was determined using the ABTS method, and the antibacterial activity was assessed through bioassays under the microwell method at nine different concentrations. The aim was to determine the diameter of the inhibition zone and, consequently, understand the sensitivity level for four bacterial species. The results revealed an antioxidant activity ranging from 90% to 94% at the sampling sites, with Wild1 standing out for having the highest average antioxidant activity values. Likewise, six out of the nine concentrations analyzed showed some degree of sensitivity for all the sampling sites. In this regard, the 25 µL mL-1 concentration showed the highest diameter of inhibition zone values, highlighting the Wild2 site, which showed an average diameter greater than 30 mm for the four bacteria tested. Only in the case of S. typhi did the CGreenhouse site surpass the Wild2, with an average diameter of the inhibition zone of 36.7 mm. These findings contribute to the search for new antioxidant and antibacterial options, addressing the challenges that humanity faces in the quest for opportunities to increase life expectancy.

5.
Gac Med Mex ; 158(4): 216-221, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36256571

RESUMO

INTRODUCTION: In current European guidelines for the management of myocardial infarction after coronary stent placement, there is no consensus on dual antiplatelet therapy (DAPT) ideal duration to prevent stent thrombosis-restenosis without significantly increasing the bleeding risk. OBJECTIVE: To report the percentage of major bleeding and presence of major cardiovascular events associated with prolonged DAPT in patients recruited at the National Institute of Cardiology, treated with primary percutaneous coronary intervention and stent. METHODS: A longitudinal, prospective, observational, non-experimental, descriptive study was carried out. Patients were recruited from November 2016 to December 2017. RESULTS: One hundred and thirty-five patients with a mean age of 57 ± 10 years who completed the three-year follow-up were selected. Obesity and hypertension stood out as the main risk factors. After using DAPT for three years, 3.7% of mortality, 1.48% of major bleeding, and 4.4% of thrombosis-restenosis were recorded. CONCLUSIONS: Prolonged use of DAPT would be justified by the high incidence of thrombosis-restenosis, without a significant increase in bleeding risk, as well as a decrease in major cardiovascular events.


INTRODUCCIÓN: En las guías actuales europeas para el manejo del infarto de miocardio posterior a la colocación de endoprótesis coronaria (stent), no existe consenso sobre la duración ideal de la terapia antiagregante plaquetaria dual (DAPT, dual antiplatelet therapy) para prevenir la trombosis-reestenosis del stent sin aumentar el riesgo significativo de sangrado. OBJETIVO: Reportar el porcentaje de sangrado mayor y de eventos cardiovasculares mayores asociados a la DAPT prolongada en pacientes atendidos en el Instituto Nacional de Cardiología y tratados con intervención coronaria percutánea primaria y stent. MÉTODOS: Se realizó un estudio longitudinal, prospectivo observacional y descriptivo no experimental. Los pacientes fueron captados de noviembre de 2016 a diciembre de 2017. RESULTADOS: Fueron seleccionados 135 pacientes con una media de edad de 57 ± 10 años, quienes cumplieron un seguimiento clínico por tres años. La obesidad y la hipertensión destacaron como principales factores de riesgo. Posterior al uso de DAPT durante tres años, se registró 3.7 % de mortalidad, 1.48 % de sangrado mayor y 4.4 % de trombosis-reestenosis. CONCLUSIONES: El uso prolongado de DAPT estaría justificado por la alta incidencia de trombosis-reestenosis, sin incremento significativo en el riesgo de sangrado y con disminución de los eventos cardiovasculares mayores.


Assuntos
Stents Farmacológicos , Infarto do Miocárdio , Trombose , Humanos , Pessoa de Meia-Idade , Idoso , Inibidores da Agregação Plaquetária/efeitos adversos , Stents Farmacológicos/efeitos adversos , Estudos Longitudinais , Estudos Prospectivos , Infarto do Miocárdio/epidemiologia , Stents/efeitos adversos , Hemorragia/epidemiologia , Trombose/complicações , Resultado do Tratamento
6.
New Phytol ; 229(1): 548-562, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32966595

RESUMO

D14 and KAI2 receptors enable plants to distinguish between strigolactones (SLs) and karrikins (KARs), respectively, in order to trigger appropriate environmental and developmental responses. Both receptors are related to the regulation of arbuscular mycorrhiza (AM) formation and are members of the RsbQ-like family of α,ß-hydrolases. DLK2 proteins, whose function remains unknown, constitute a third clade from the RsbQ-like protein family. We investigated whether the tomato SlDLK2 is a new regulatory component in the AM symbiosis. Genetic approaches were conducted to analyze SlDLK2 expression and to understand SlDLK2 function in AM symbiosis. We show that SlDLK2 expression in roots is AM-dependent and is associated with cells containing arbuscules. SlDLK2 ectopic expression arrests arbuscule branching and downregulates AM-responsive genes, even in the absence of symbiosis; while the opposite effect was observed upon SlDLK2 silencing. Moreover, SlDLK2 overexpression in Medicago truncatula roots showed the same altered phenotype observed in tomato roots. Interestingly, SlDLK2 interacts with DELLA, a protein that regulates arbuscule formation/degradation in AM roots. We propose that SlDLK2 is a new component of the complex plant-mediated mechanism regulating the life cycle of arbuscules in AM symbiosis.


Assuntos
Medicago truncatula , Micorrizas , Regulação da Expressão Gênica de Plantas , Medicago truncatula/genética , Medicago truncatula/metabolismo , Micorrizas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Simbiose
7.
BMC Med Res Methodol ; 21(1): 153, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34311704

RESUMO

BACKGROUND: The Iberoamerican Cochrane Network is currently developing an extensive project to identify Spanish-language journals that publish original clinical research in Spain and Latin America. The project is called BADERI (Database of Iberoamerican Essays and Journal) and feeds the research articles, mainly randomised clinical trials (RCTs), into CENTRAL (Cochrane Collaboration Central Register of Controlled Trials). This study aims to assess the quality of reporting of RCTs published in Spanish and Latin American journals for three clinical fields and assess changes over time. METHODS: We did a systematic survey with time trend analysis of RCTs for dentistry, geriatrics, and neurology. These fields were chosen for pragmatic reasons as they had not yet been completed in BADERI. After screening RCTs from 1990 to 2018 for randomised or quasi-randomised clinical trials, we extracted data for 23 CONSORT items. The primary outcome was the total score of the 23 predefined CONSORT 2010 items for each RCT (score range from 0 to 34). The secondary outcome measure was the score for each one of these 23 items. RESULTS: A total of 392 articles from 1990 to 2018 were included as follows: dentistry (282), neurology (80), and geriatrics (30). We found that the overall compliance score for the CONSORT items included in this study for all 392 RCTs analysed was 12.6 on a scale with a maximum score of 34. With time, the quality of reporting improved slightly for all RCTs. None of the articles achieved the complete individual CONSORT item compliance score. The lowest overall compliance percentage was for item 10 (Randomisation implementation) and item 24 (Protocol registration), with a dismal 1% compliance across all included RCTs, regardless of country. CONCLUSIONS: CONSORT compliance is very poor in the 392 analysed RCTs. The impact of the CONSORT statement on improving the completeness of RCT reporting in Latin America and Spain is not clear. Iberoamerican journals should become more involved in endorsing and enforcing adherence to the CONSORT guidelines.


Assuntos
Geriatria , Neurologia , Publicações Periódicas como Assunto , Odontologia , Humanos , América Latina , Espanha
8.
Vet Pathol ; 57(2): 321-331, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32079504

RESUMO

Bicuspid aortic valve (BAV) is the most common human congenital cardiac malformation. Although the etiology is unknown for most patients, formation of the 2 main BAV anatomic types (A and B) has been shown to rely on distinct morphogenetic mechanisms. Animal models of BAV include 2 spontaneous hamster strains and 27 genetically modified mouse strains. To assess the value of these models for extrapolation to humans, we examined the aortic valve anatomy of 4340 hamsters and 1823 mice from 8 and 7 unmodified strains, respectively. In addition, we reviewed the literature describing BAV in nonhuman mammals. The incidences of BAV types A and B were 2.3% and 0.03% in control hamsters and 0% and 0.3% in control mice, respectively. Hamsters from the spontaneous model had BAV type A only, whereas mice from 2 of 27 genetically modified strains had BAV type A, 23 of 27 had BAV type B, and 2 of 27 had both BAV types. In both species, BAV incidence was dependent on genetic background. Unlike mice, hamsters had a wide spectrum of aortic valve morphologies. We showed interspecific differences in the occurrence of BAV between humans, hamsters, and mice that should be considered when studying aortic valve disease using animal models. Our results suggest that genetic modifiers play a significant role in both the morphology and incidence of BAV. We propose that mutations causing anomalies in specific cardiac morphogenetic processes or cell lineages may lead to BAV types A, B, or both, depending on additional genetic, environmental, and epigenetic factors.


Assuntos
Doença da Válvula Aórtica Bicúspide/genética , Animais , Valva Aórtica/anormalidades , Doença da Válvula Aórtica Bicúspide/epidemiologia , Cricetinae , Modelos Animais de Doenças , Humanos , Incidência , Camundongos , Mutação , Estudos Retrospectivos
9.
J Fish Biol ; 97(3): 734-739, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32515493

RESUMO

The atrioventricular junction of the fish heart, namely the segment interposed between the single atrium and the single ventricle, has been studied anatomically and histologically in several chondrichthyan and teleost species. Nonetheless, knowledge about myosin heavy chain (MyHC) in the atrioventricular myocardium remains scarce. The present report is the first one to provide data on the MyHC isoform distribution in the myocardium of the atrioventricular junction in chondrichthyans, specifically in the lesser spotted dogfish, Scyliorhinus canicula, a shark species whose heart reflects the primitive cardiac anatomical design in gnathostomes. Hearts from five dogfish were examined using histochemical and immunohistochemical techniques. The anti-MyHC A4.1025 antibody was used to detect differences in the occurrence of MyHC isoforms in the dogfish, as the fast-twitch isoforms MYH2 and MYH6 have a higher affinity for this antibody than the slow-twitch isoforms MYH7 and MYH7B. The histochemical findings show that myocardium of the atrioventricular junction connects the trabeculated myocardium of the atrium with the trabeculated layer of the ventricular myocardium. The immunohistochemical results indicate that the distribution of MyHC isoforms in the atrioventricular junction is not homogeneous. The atrial portion of the atrioventricular myocardium shows a positive reactivity against the A4.1025 antibody similar to that of the atrial myocardium. In contrast, the ventricular portion of the atrioventricular junction is not labelled, as is the case with the ventricular myocardium. This dual condition suggests that the myocardium of the atrioventricular junction has two contraction patterns: the myocardium of the atrial portion contracts in line with the atrial myocardium, whereas that of the ventricular portion follows the contraction pattern of the ventricular myocardium. Thus, the transition of the contraction wave from the atrium to the ventricle may be established in the atrioventricular segment because of its heterogeneous MyHC isoform distribution. The findings support the hypothesis that a distinct MyHC isoform distribution in the atrioventricular myocardium enables a synchronous contraction of inflow and outflow cardiac segments in vertebrates lacking a specialized cardiac conduction system.


Assuntos
Cação (Peixe) , Miocárdio/química , Cadeias Pesadas de Miosina/química , Animais , Anticorpos/metabolismo , Cadeias Pesadas de Miosina/isolamento & purificação , Isoformas de Proteínas
10.
Front Zool ; 16: 18, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31198434

RESUMO

BACKGROUND: Immunohistochemical studies of hearts from the lesser spotted dogfish, Scyliorhinus canicula (Chondrichthyes) revealed that the pan-myosin heavy chain (pan-MyHC) antibody MF20 homogeneously labels all the myocardium, while the pan-MyHC antibody A4.1025 labels the myocardium of the inflow (sinus venosus and atrium) but not the outflow (ventricle and conus arteriosus) cardiac segments, as opposed to other vertebrates. We hypothesized that the conventional pattern of cardiac MyHC isoform distribution present in most vertebrates, i.e. MYH6 in the inflow and MYH7 in the outflow segments, has evolved from a primitive pattern that persists in Chondrichthyes. In order to test this hypothesis, we conducted protein detection techniques to identify the MyHC isoforms expressed in adult dogfish cardiac segments and to assess the pan-MyHC antibodies reactivity against the cardiac segments of representative species from different vertebrate groups. RESULTS: Western and slot blot results confirmed the specificity of MF20 and A4.1025 for MyHC in dogfish and their differential reactivity against distinct myocardial segments. HPLC-ESI-MS/MS and ESI-Quadrupole-Orbitrap revealed abundance of MYH6 and MYH2 in the inflow and of MYH7 and MYH7B in the outflow segments. Immunoprecipitation showed higher affinity of A4.1025 for MYH2 and MYH6 than for MYH7 and almost no affinity for MYH7B. Immunohistochemistry showed that A4.1025 signals are restricted to the inflow myocardial segments of elasmobranchs, homogeneous in all myocardial segments of teleosts and acipenseriforms, and low in the ventricle of polypteriforms. CONCLUSIONS: The cardiac inflow and outflow segments of the dogfish show predominance of fast- and slow-twitch MyHC isoforms respectively, what can be considered a synapomorphy of gnathostomes. The myocardium of the dogfish contains two isomyosins (MYH2 and MYH7B) not expressed in the adult heart of other vertebrates. We propose that these isomyosins lost their function in cardiac contraction during the evolution of gnathostomes, the later acquiring a regulatory role in myogenesis through its intronic miRNA. Loss of MYH2 and MYH7B expression in the heart possibly occurred before the origin of Osteichthyes, being the latter reacquired in polypteriforms. We raise the hypothesis that the slow tonic MYH7B facilitates the peristaltic contraction of the conus arteriosus of fish with a primitive cardiac anatomical design and of the vertebrate embryo.

11.
Parasitol Res ; 118(5): 1353-1361, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30868295

RESUMO

Antarctophthirus microchir is a sucking louse species belonging to the family Echinophthiriidae and has been reported to parasitize all species of the subfamily Otariinae, the sea lions. Former studies on this ectoparasite mainly required fixation, immobilization, or death of host species and especially examinations of adult male sea lions are still very rare. Between March and May 2018, adult individuals of a unique "urban" bachelor group of South American sea lions (Otaria flavescens) living directly in the city of Valdivia, Chile, were studied regarding their ectoparasite infestation status. For first time, a non-invasive method in the form of a lice comb screwed on a telescopic rod and grounded with adhesive tape was used for sample taking process. Overall, during combing different stages of A. microchir were detected in 4/5 O. flavescens individuals, especially at the junction between the back and hind flippers. Our findings represent the first report of A. microchir infesting individuals of this synanthropic colony and fulfilling complete life cycle in a sea lion group despite inhabiting freshwater and in absence of females/pups. Our "telescopic lice comb apparatus" offers a new strategy to collect different stages of ectoparasites and a range of epidermal material, such as fur coat hair and superficial skin tissue for a broad spectrum of research fields in wildlife sciences in an unmolested and stress reduced manner.


Assuntos
Anoplura/classificação , Infestações por Piolhos/diagnóstico , Doenças Parasitárias em Animais/diagnóstico , Leões-Marinhos/parasitologia , Animais , Chile , Estágios do Ciclo de Vida , Masculino , Doenças Parasitárias em Animais/parasitologia
12.
Dis Aquat Organ ; 120(3): 205-15, 2016 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-27503916

RESUMO

Francisellosis, an emerging disease in tilapia Oreochromis spp., is caused by the facultative, intracellular bacterium Francisella noatunensis subsp. orientalis, which is present in various countries where tilapia farming is commercially important. We confirmed the presence of francisellosis in Mexican tilapia cultures in association with an outbreak during the second semester of 2012. Broodstock fish presented a mortality rate of approximately 40%, and disease was characterized by histologically classified granulomas, or whitish nodules, in different organs, mainly the spleen and kidney. Through DNA obtained from infected tissue and pure cultures in a cysteine heart medium supplemented with hemoglobin, F. noatunensis subsp. orientalis was initially confirmed through the amplification and analysis of the 16S rRNA gene and the internal transcribed spacer region. Phylogenetic analysis of these genes demonstrated close similarity with previously reported F. noatunensis subsp. orientalis sequences obtained from infected tilapia from various countries. The identification of this subspecies as the causative agent of the outbreak was confirmed using the iglC gene as a target sequence, which showed 99.5% identity to 2 F. noatunensis subsp. orientalis strains (Ethime-1 and Toba04). These findings represent the first documented occurrence of francisellosis in Mexican tilapia cultures, which highlights the importance of establishing preventative measures to minimize the spread of this disease within the Mexican aquaculture industry.


Assuntos
Doenças dos Peixes/microbiologia , Francisella/isolamento & purificação , Infecções por Bactérias Gram-Negativas/veterinária , Tilápia , Animais , Aquicultura , DNA Bacteriano/genética , DNA Espaçador Ribossômico/genética , Doenças dos Peixes/epidemiologia , Francisella/classificação , Francisella/genética , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , México/epidemiologia , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
13.
Enferm Infecc Microbiol Clin ; 32(10): 681-8, 2014 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-25023372

RESUMO

This article aims to provide a brief review of the main concepts on which the prevention and control of infection are based. Antisepsis comprises a set of techniques aimed at the total sterilization, or at most, disinfection, removing germs that contaminate an environment. Both procedures must be preceded by an environmental cleanup in the location in which they intend to be applied. The disinfection is carried out using biocides or germicides. Antimicrobial chemicals, that have mechanisms of action and resistances very similar to antibiotics, are generating concern due to the possibility of crossing genetic information that aggravates the problem of bacterial resistance. Most biocides can act as antiseptics, and applied to skin tissue, or disinfectants on inanimate materials. The spectrum of action of germicides depends on the product itself and external controllable factors: temperature, concentration, exposure time, etc. Sterilization techniques are primarily physical, by exposing the material to steam, or sterilizing gas, using autoclaves. Major advances are the use of low temperatures with shorter exposure times, in parallel with technological advances in instrumentation in order to avoid high temperatures and high use rotations due to workload.


Assuntos
Antissepsia/métodos , Antissepsia/normas , Controle de Infecções/métodos , Esterilização/métodos , Esterilização/normas , Desinfetantes/farmacologia , Desinfecção/métodos , Desinfecção/normas , Resistência a Medicamentos , Contaminação de Equipamentos/prevenção & controle , Humanos , Pele
14.
Sensors (Basel) ; 14(3): 4791-805, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24618726

RESUMO

A review of the surface plasmon resonance (SPR) transducers based on tapered fibers that have been developed in the last years is presented. The devices have proved their good performance (specifically, in terms of sensitivity) and their versatility and they are a very good option to be considered as basis for any kind of chemical and biological sensor. The technology has now reached its maturity and here we summarize some of the characteristics of the devices produced.


Assuntos
Fibras Ópticas , Ressonância de Plasmônio de Superfície/instrumentação , Absorção de Radiação , Fenômenos Ópticos
15.
Medwave ; 23(11): e2787, 2023 Dec 20.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38117982

RESUMO

Based on the recommendations of the Vaccine Advisory Committee and the National Immunization Program, Chile implemented an early vaccination process of the population with vaccines from different laboratories. The study of neutralizing antibody levels in different population subgroups contributes to the establishment of correlates of protection against SARS-CoV-2 infection. In 2022 and 2023 we set up a community cohort of 914 adults with cardiovascular risk factors. In this cohort we are measuring the humoral immune response to exposure to SARS-CoV-2 antigens, either by vaccines or infection, as well as the incidence of COVID-19 and other adverse events. This cohort, which we call The COmmunity Cohort, is providing us with valuable information on the levels of neutralizing antibodies in these individuals and their degree of protection against COVID-19.


A partir de las recomendaciones emanadas del Comité Asesor en Vacunas y el Programa Nacional de Inmunizaciones, Chile implementó precozmente un proceso de vacunación de la población con vacunas provenientes de diferentes laboratorios. El estudio de los niveles de anticuerpos neutralizantes en diferentes subgrupos poblacionales, contribuye al establecimiento de los correlatos de protección frente a infección por SARS-CoV-2. En 2022 y 2023 establecimos una cohorte comunitaria de 914 adultos con factores de riesgo cardiovascular. En esta cohorte estamos midiendo la respuesta inmune humoral frente a exposición a antígenos de SARS-CoV-2, ya sea por vacunas o por infección, así como la incidencia de COVID-19 y otros eventos adversos. Esta cohorte, que llamamos, nos está entregando valiosa información sobre los niveles de anticuerpos neutralizantes en estas personas y su grado de protección frente al COVID-19.


Assuntos
COVID-19 , Vacinas , Adulto , Humanos , SARS-CoV-2 , Imunidade Humoral , Estudos de Coortes , Vacinação
16.
Medwave ; 23(1): e2665, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36820833

RESUMO

A well-informed diagnostic process results in better health outcomes and less overdiagnosis. While there have been studies conducted to explore doctors' knowledge, attitudes, and practice regarding diagnostic test information, there are no reports from Latin America. We invited physician readers of a Latin American medical journal to answer a survey on their professional and demographic characteristics and previous exposure to diagnostic information training. Two hundred fifteen responded, of whom 88% agreed to some extent that diagnostic information is helpful for clinical practice and that more training is needed. This brief exploratory survey underscores the need for more resources to train in the diagnostic process and the utilization of diagnostic information in clinical practice. However, given the limitations of this study, more evidence is needed.


Un proceso de diagnóstico bien informado da lugar a mejores resultados de salud y a menos sobrediagnósticos. Aunque se han realizado estudios para explorar los conocimientos, las actitudes y la práctica de los médicos en relación con la información sobre las pruebas diagnósticas, no existen estudios realizados en América Latina. Invitamos a los médicos lectores de una revista médica latinoamericana a responder una encuesta de opinión sobre sus características profesionales y demográficas y su exposición previa a la formación en información diagnóstica. Recibimos 215 respuestas, de las cuales el 88% estuvo de acuerdo en que la información diagnóstica es útil para la práctica clínica, y que se necesita más capacitación. Esta breve encuesta exploratoria subraya la necesidad de dedicar más recursos en la formación sobre el proceso diagnóstico y la utilización de la información diagnóstica en la práctica clínica. Sin embargo, dado las limitaciones de este estudio se hace necesario mayor evidencia al respecto.


Assuntos
Médicos , Humanos , Inquéritos e Questionários , Percepção , Atitude do Pessoal de Saúde , Padrões de Prática Médica , Conhecimentos, Atitudes e Prática em Saúde
17.
Reprod Biol ; 23(2): 100756, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36924552

RESUMO

Ovarian functions are modulated by the hypothalamus-pituitary-ovary axis and neural signals. Stress modifies the activity of the sympathetic nervous system. In adult female rats, cold stress results in higher noradrenergic and steroidogenic activity of the ovary, anovulation and the presence of ovarian cysts; however, it is unknown whether this response occurs in prepubertal rats. The purpose of this study was to analyse the effects of cold stress initiated in the prepubertal stage of female rats on ovarian function. Female rats 24 days old were exposed to three, five or eight weeks of cold stress. Autopsies were performed at the end of each stress period. The parameters analysed were the number of ova shed by ovulating animals; the number of ovulating animals; the serum concentrations of progesterone, testosterone, and oestradiol; and the ovarian concentrations of norepinephrine and 3-methoxy-4-hydroxyphenyl-glycol. Our results show that chronic cold stress applied to prepubertal rats did not modify the number of ovulating animals, the total number of ova shed, or progesterone and testosterone concentrations in any of the periods analysed. Oestradiol concentration was lower in the animals exposed to five or eight weeks of stress. The ovarian norepinephrine concentration was higher in the animals exposed to three weeks of stress and was lower at eight weeks of stress. No changes in ovarian morphology were observed. Our data suggest that the changes in noradrenergic activity resulting from chronic cold stress experienced in the prepubertal stage do not modify ovarian architecture or affect the ovulatory response in adulthood.


Assuntos
Resposta ao Choque Frio , Progesterona , Ratos , Animais , Feminino , Estradiol , Norepinefrina/fisiologia , Testosterona
18.
Antibiotics (Basel) ; 12(12)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38136686

RESUMO

Oxytetracycline (OTC) is administered in the poultry industry for the treatment of digestive and respiratory diseases. The use of OTC may contribute to the selection of resistant bacteria in the gastrointestinal tract of birds or in the environment. To determine the effect of OTC on the selection of resistant Escherichia coli strains post-treatment, bacteria were isolated from droppings and litter sampled from untreated and treated birds. Bacterial susceptibility to tetracyclines was determined by the Kirby-Bauer test. A total of 187 resistant isolates were analyzed for the presence of tet(A), (B), (C), (D), (E), and (M) genes by PCR. Fifty-four strains were analyzed by PFGE for subtyping. The proportion of tetracycline-resistant E. coli strains isolated was 42.88%. The susceptibility of the strains was treatment-dependent. A high clonal diversity was observed, with the tet(A) gene being the most prevalent, followed by tet(C). Even at therapeutic doses, there is selection pressure on resistant E. coli strains. The most prevalent resistance genes were tet(A) and tet(C), which could suggest that one of the main mechanisms of resistance of E. coli to tetracyclines is through active efflux pumps.

19.
Vasc Endovascular Surg ; 57(5): 490-493, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36632767

RESUMO

Background: Varicose pubic collateral veins are a rare phenomenon secondary to obstruction of the common femoral vein, left external iliac, or common iliac vein. This article aims to describe the clinical case of a 75-year-old female patient who presented with varicose collateral suprapubic veins.Case report: A 75-year-old female patient from a rural area in Colombia presented to the emergency department complaining of a 4-day history of edema, erythema, and pain in the suprapubic region. The patient presented with large varicose veins in the suprapubic region with erythema, warmth, and pain on palpation. A computer tomography scan of the abdomen and pelvis showed suprapubic varicose veins and contrasted in venous phase ruled out iliac vein obstruction. To rule out paraneoplastic syndrome, tumor markers, a transvaginal ultrasound, esophagogastroduodenoscopy and rectosigmoidoscopy were obtained and found to be negative. Anticoagulation with warfarin 5 mg daily and bridge therapy with enoxaparin was initiated.Conclusion: We presented the case of a patient with varicose collateral suprapubic veins of unknown origin, who received anticoagulation with warfarin and analgesic management with subsequent resolution of symptoms.


Assuntos
Varizes , Varfarina , Feminino , Humanos , Idoso , Flebografia/métodos , Resultado do Tratamento , Varizes/diagnóstico por imagem , Varizes/terapia , Pelve/irrigação sanguínea , Veia Ilíaca , Dor , Anticoagulantes
20.
Arch Cardiol Mex ; 93(2): 197-202, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37037216

RESUMO

INTRODUCTION: Coronary Ectasia (CE) is a pathological remodeling with a low worldwide prevalence. It is defined as a diffuse dilatation greater than 1.5 times the diameter of the adjacent segments of the same or different coronary arteries. OBJECTIVE: To document the clinical and angiographic characteristics, and medical treatment at the discharge of patients diagnosed with coronary ectasia who attended the National Institute of Cardiology (INC). METHODS: Cross-sectional study with a non-experimental descriptive design, with a non-probabilistic convenience sampling. RESULTS: Of 69 patients who attended the INC with a diagnosis of CD, most were men, with a mean age of 56 + 11 years, the most common coronary risk factor in patients with CE was smoking 58% (40); it was associated mostly with an acute myocardial infarction ST-segment elevation (STEMI) 65.2% (45), of frequent location in the lower face 40% (18), correlated with the most affected artery is the Right Coronary Artery (CD) 69.6% (48), followed by the circumflex (Cx) 56.5% (39). A mean LVEF of 47 + 9.72 was evident within the ventricular function. As well as the preferential use of dual antiplatelet therapy with anticoagulant (DAP + OAC) in 58% (40) at the discharge of each patient from the INC. CONCLUSION: CE is a not uncommon pathological remodeling in INC. This study showed that STEMI is the most typical manifestation of CE, diagnostic coronary angiography identified a type 3 Markis, so a low rate of mortality and recurrence of cardiovascular events would be expected, and despite the lack of consensus on the ideal therapy, at the INC individualized treatment is preferred, recommending lifestyle changes, and using triple therapy (DAP + OAC) as a medical treatment only at the time of patient discharge.


INTRODUCCIÓN: La ectasia coronaria (EC) es una remodelación patológica con una prevalencia mundial baja. Se define como una dilatación difusa mayor a 1.5 veces el diámetro de los segmentos adyacentes de esta o diferentes arterias coronarias. OBJETIVO: Documentar las características clínicas y angiográficas, y el tratamiento médico que reciben los pacientes con diagnóstico de EC en el Instituto Nacional de Cardiología (INC). MÉTODOS: Estudio de tipo transversal con diseño no experimental descriptivo, con un muestreo por conveniencia no probabilístico. RESULTADOS: De 69 pacientes que asistieron al INC con diagnóstico de EC la mayor parte eran hombres, con una media de edad de 56 ± 11 años, el factor de riesgo coronario más común en los pacientes con EC fue el tabaquismo, en 40 (58%); se asoció un infarto agudo de miocardio con elevación del segmento ST (IAMCEST) en 45 (65.2%), de localización frecuente en la cara inferior 18 (40%), relacionado con la arteria más afectada, la coronaria derecha 48 (69.6%), seguida de la circunfleja 39 (56.5%). Destaca el uso preferente de la terapia antiplaquetaria dual con anticoagulante (APD+ACO) en 40 (58%) al egreso de cada paciente del INC. CONCLUSIÓN: La EC es una remodelación patológica no infrecuente en el INC. En este estudio se evidenció que el SCA-IAMCEST es la manifestación más típica de la EC, la coronariografía diagnóstica identificó un Markis tipo 3, por lo que se esperaría una tasa baja de mortalidad y recurrencia de eventos cardiovasculares y a pesar de no existir un consenso sobre la terapia ideal, en el INC se prefiere el tratamiento individualizado, recomendando modificación en el estilo de vida y empleando como tratamiento médico el uso de la triple terapia (APD+ACO) solo al momento de egreso del paciente.


Assuntos
Cardiologia , Infarto do Miocárdio com Supradesnível do Segmento ST , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Estudos Transversais , Dilatação Patológica , Coração , Angiografia Coronária , Vasos Coronários
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