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1.
Infect Immun ; 91(12): e0024523, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37916806

RESUMO

Virus-like particles (VLPs) are promising nanotools for the development of subunit vaccines due to high immunogenicity and safety. Herein, we explored the versatile and effective Tag/Catcher-AP205 capsid VLP (cVLP) vaccine platform to address the urgent need for the development of an effective and safe vaccine against gonorrhea. The benefits of this clinically validated cVLP platform include its ability to facilitate unidirectional, high-density display of complex/full-length antigens through an effective split-protein Tag/Catcher conjugation system. To assess this modular approach for making cVLP vaccines, we used a conserved surface lipoprotein, SliC, that contributes to the Neisseria gonorrhoeae defense against human lysozyme, as a model antigen. This protein was genetically fused at the N- or C-terminus to the small peptide Tag enabling their conjugation to AP205 cVLP, displaying the complementary Catcher. We determined that SliC with the N-terminal SpyTag, N-SliC, retained lysozyme-blocking activity and could be displayed at high density on cVLPs without causing aggregation. In mice, the N-SliC-VLP vaccines, adjuvanted with AddaVax or CpG, induced significantly higher antibody titers compared to controls. In contrast, similar vaccine formulations containing monomeric SliC were non-immunogenic. Accordingly, sera from N-SliC-VLP-immunized mice also had significantly higher human complement-dependent serum bactericidal activity. Furthermore, the N-SliC-VLP vaccines administered subcutaneously with an intranasal boost elicited systemic and vaginal IgG and IgA, whereas subcutaneous delivery alone failed to induce vaginal IgA. The N-SliC-VLP with CpG (10 µg/dose) induced the most significant increase in total serum IgG and IgG3 titers, vaginal IgG and IgA, and bactericidal antibodies.


Assuntos
Neisseria gonorrhoeae , Vacinas de Partículas Semelhantes a Vírus , Animais , Feminino , Humanos , Camundongos , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Capsídeo , Imunoglobulina A , Imunoglobulina G , Camundongos Endogâmicos BALB C , Muramidase , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/imunologia , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia
2.
J Craniofac Surg ; 33(7): e680-e685, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35148530

RESUMO

ABSTRACT: Mandibular reconstruction is a challenging procedure, especially in cancer patients with defects that are greater than 6 cm. Free vascularized fibular flap is the gold standard treatment in these cases since it allows three-dimensional restoration of the lost segments after ablative surgery in addition to providing the possibility of a subsequent implant-supported rehabilitation improving the functional and aesthetic outcomes of the surgery.To obtain accurate results, preoperative planning must be done with detail. Approaches for the preoperative planning include both the conventional analog planning and the virtual planning that are valid alternatives in meeting the trans-surgical requirements.This study makes a comparative analysis of 2 clinical cases with a diagnosis of squamous cell carcinoma that were reconstructed using a vascularized fibular free flap. The first case was planned using the conventional analog method whereas the second case was planned using the virtual planning approach.The impact of virtual planning and conventional analog planning on preoperative planning time, ischemia period, and total surgical time is analyzed according to the experience obtained in the cases presented. In addition, the authors described the technique used for each planning method along with a literature review in which the results are contrasted and discussed.


Assuntos
Retalhos de Tecido Biológico , Reconstrução Mandibular , Transplante Ósseo , Estética Dentária , Fíbula/cirurgia , Humanos , Mandíbula/cirurgia , Reconstrução Mandibular/métodos , Duração da Cirurgia
3.
J Antimicrob Chemother ; 73(6): 1611-1619, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29506074

RESUMO

Background: Klebsiella pneumoniae is an opportunistic pathogen and many strains are multidrug resistant. KPC is one of the most problematic resistance mechanisms, as it confers resistance to most ß-lactams, including carbapenems. A promising platform technology for treating infections caused by MDR pathogens is the nucleic acid-like synthetic oligomers that silence bacterial gene expression by an antisense mechanism. Objectives: To test a peptide-conjugated phosphorodiamidate morpholino oligomer (PPMO) in a mouse model of K. pneumoniae infection. Methods: PPMOs were designed to target various essential genes of K. pneumoniae and screened in vitro against a panel of diverse strains. The most potent PPMOs were further tested for their bactericidal effects in broth cultures and in established biofilms. Finally, a PPMO was used to treat mice infected with a KPC-expressing strain. Results: The most potent PPMOs targeted acpP, rpmB and ftsZ and had MIC75s of 0.5, 4 and 4 µM, respectively. AcpP PPMOs were bactericidal at 1-2 × MIC and reduced viable cells and biofilm mass in established biofilms. In a mouse pneumonia model, therapeutic intranasal treatment with ∼30 mg/kg AcpP PPMO improved survival by 89% and reduced bacterial burden in the lung by ∼3 logs. Survival was proportional to the dose of AcpP PPMO. Delaying treatment by 2, 8 or 24 h post-infection improved survival compared with control groups treated with PBS or scrambled sequence (Scr) PPMOs. Conclusions: PPMOs have the potential to be effective therapeutic agents against KPC-expressing, MDR K. pneumoniae.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Klebsiella pneumoniae/efeitos dos fármacos , Morfolinos/farmacologia , Animais , Modelos Animais de Doenças , Feminino , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/genética , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Morfolinos/síntese química , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Bacteriana/microbiologia
4.
Medicina (B Aires) ; 76(5): 321-325, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-27723623

RESUMO

Pacemaker stimulation is associated with unpredictable severe cardiac events. We evaluated left ventricular mechanical dyssynchrony (LVMD) during prolonged septal right ventricular pacing. We performed 99mTc-MIBI gated-SPECT and phase analysis in 6 patients with pacemakers implanted at least one year before scintigraphy due to advanced atrioventricular block. Using V-Sync of Emory Cardiac Toolbox we obtained phase bandwidth (PBW) and standard deviation (PSD) from rest phase histogram. Clinical variables, QRS duration, rate and mode of pacing in septal right ventricle wall, chamber diameters, presence and extension of myocardial scar and ischemia and rest LVEF were recorded. Prolonged septal endocardial pacing is associated with marked LVMD, even when systolic function was preserved. More severe dyssynchrony was found in patients with impaired LVEF, higher left ventricle diameters, extensive infarct or severe ischemia than in patients with preserved LVEF (PBW: 177.3o vs. 88.3o; PSD: 53.1o vs. 33.8o). In the patients with ischemic heart disease and pacemaker, gated-SPECT phase analysis is a valid and potentially useful technique to evaluate LMVD associated with myocardial scar and to decide the upgrading to biventricular pacing mode.


Assuntos
Marca-Passo Artificial/efeitos adversos , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia , Septo Interventricular/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Bloqueio Atrioventricular/cirurgia , Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca , Eletrocardiografia , Feminino , Humanos , Masculino , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/etiologia , Índice de Gravidade de Doença , Disfunção Ventricular Esquerda/diagnóstico por imagem , Septo Interventricular/diagnóstico por imagem
5.
Gac Med Mex ; 151(1): 66-74, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-25739486

RESUMO

There have been major recent advances in the field of developmental biology due to the investigation on stem cells (SC). Stem cells are characterized by their capacity of auto-renewal and differentiation to different cellular phenotypes. Based on the developmental stage, they can be classified into two different types: embryonic SCs and adult SCs. It has been widely reported that several problems need to be resolved before their possible clinical applications. As a result, fetal membranes have been suggested as an alternative source of SCs. In the human amniotic epithelium, the presence of markers of pluripotent SC´s has been reported, and its capacity as a feeder layer for expansion of different SC types. Also, fetal membranes are a discarded product after delivery, and thus there are not any ethical issues related to its use. In conclusion, the human amniotic epithelium can be a strong candidate for regenerative medicine.


Assuntos
Âmnio/citologia , Células Epiteliais/citologia , Células-Tronco/citologia , Diferenciação Celular , Membranas Extraembrionárias/citologia , Humanos , Medicina Regenerativa/métodos
6.
Mod Pathol ; 27(3): 402-11, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24030746

RESUMO

Primary cutaneous large B-cell lymphoma, leg type has been individualized from nodal diffuse large B-cell lymphoma. The objective of this study was to screen primary cutaneous large B-cell lymphoma, leg type for genetic alterations recently described in nodal diffuse large B-cell lymphoma. Skin biopsies from 23 patients were analyzed for IRF4, BCL2, BCL6, and MYC expression. FISH testing was performed for BCL2, BCL6, MYC with separation probes and for CDKN2A and PRDM1/BLIMP1 deletion. Multiple sequential FISH analyses with up to six probes were performed to define samples with multiple cytogenetic alterations. MYD88 mutations were studied by Sanger sequencing. All cases but one displayed at least one genetic alteration (96%). Nine patients exhibited a single genetic mutation and 12 combined several alterations (52%). We observed a split for BCL2, BCL6, or MYC in 1/23, 6/23, and 3/23 of cases, respectively. No double-hit lymphoma was observed. CDKN2A deletion was detected by FISH in only 5/23 cases. BLIMP1 and/or 6q deletion was observed at a higher rate in 10/20 of cases. No correlation between rearrangement and immunohistochemical expression was found for BCL2 or MYC. FISH tracking of sequential hybridizations showed that several alterations were carried by the same nuclei. The p.L265P MYD88 mutation was found in 11/18 (61%) of cases. Contrary to most cutaneous lymphomas that rarely harbor primary genetic alteration of their nodal histological equivalent, primary cutaneous large B-cell lymphoma, leg type seems to be a 'cutaneous counterpart' of activated B-cell-like diffuse large B-cell lymphoma with a similar cytogenetic profile and a high rate of MYD88 oncogenic L265P mutation. This also suggests a common lymphomagenesis with NF-κB activation, strong IRF4 expression and terminal B-cell differentiation blockage. Our data support the use of therapies targeting NF-κB, as most patients displayed disease progression and resistance to conventional therapies.


Assuntos
Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Perna (Membro)/patologia , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/mortalidade
7.
ACS Appl Polym Mater ; 5(2): 1180-1190, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36817334

RESUMO

Hydrogels are commonly used materials in tissue engineering and organ-on-chip devices. This study investigated the nanomechanical properties of monolithic and multilayered poly(ethylene glycol) diacrylate (PEGDA) hydrogels manufactured using bulk polymerization and layer-by-layer projection lithography processes, respectively. An increase in the number of layers (or reduction in layer thickness) from 1 to 8 and further to 60 results in a reduction in the elastic modulus from 5.53 to 1.69 and further to 0.67 MPa, respectively. It was found that a decrease in the number of layers induces a lower creep index (CIT) in three-dimensional (3D) printed PEGDA hydrogels. This reduction is attributed to mesoscale imperfections that appear as pockets of voids at the interfaces of the multilayered hydrogels attributed to localized regions of unreacted prepolymers, resulting in variations in defect density in the samples examined. An increase in the degree of cross-linking introduced by a higher dosage of ultraviolet (UV) exposure leads to a higher elastic modulus. This implies that the elastic modulus and creep behavior of hydrogels are governed and influenced by the degree of cross-linking and defect density of the layers and interfaces. These findings can guide an optimal manufacturing pathway to obtain the desirable nanomechanical properties in 3D printed PEGDA hydrogels, critical for the performance of living cells and tissues, which can be engineered through control of the fabrication parameters.

8.
Int J Biol Macromol ; 168: 722-732, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33232700

RESUMO

Natural polymer-based hybrid nanocomposites have been proposed as one of the most promising tools for biomedical applications, including disease treatment and diagnosis procedures. Xyloglucan nanocapsules can simultaneously load magnetic iron oxide nanoparticles and bioactive for a specific tissue, reducing the processes of degradation and metabolic inactivation of molecules with biological activity. In this work, magnetic nanocapsules of xyloglucan loaded with hydrophilic sulfated quercetin (MNXQ_SO3) were successfully synthesized by inverse miniemulsion process through interfacial polymerization. The polymeric shell formation of nanocapsules was evidenced by Fourier Transform Infrared spectroscopy and Transmission Electron Microscopy. The ferrofluid (Fe3O4@PAAS) incorporated into the xyloglucan nanocapsules was synthesized by hydrothermal method, using polyacrylic acid sodium salt as coating. Dynamic Light Scattering technique confirmed the nanomeric dimensions (202.3 nm) and the good colloidal stability (-40.2 mV) of MNXQ_SO3. The saturation magnetization analyses pointed out the superparamagnetic behavior of Fe3O4@PAAS (48 emu/g) and MNXQ_SO3 (4.2 emu/g). MNXQ_SO3 was able to modify the release profile of sulfated quercetin (67%) when compared to the free bioactive (100%), exhibiting a release profile compatible with the zero-order kinetic model. The results showed that the development of MNXQ_SO3 presents a new perspective for biomedical applications, including studies of targeted drug delivery.


Assuntos
Glucanos/química , Quercetina/síntese química , Sulfetos/química , Xilanos/química , Sistemas de Liberação de Medicamentos , Difusão Dinâmica da Luz , Cinética , Nanopartículas de Magnetita , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Quercetina/química , Quercetina/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Front Microbiol ; 11: 607693, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33519754

RESUMO

Codon usage bias (the preferential use of certain synonymous codons (optimal) over others is found at the organism level (intergenomic) within specific genomes (intragenomic) and even in certain genes. Whether it is the result of genetic drift due to GC/AT content and/or natural selection is a topic of intense debate. Preferential codons are mostly found in genes encoding highly-expressed proteins, while lowly-expressed proteins usually contain a high proportion of rare (lowly-represented) codons. While optimal codons are decoded by highly expressed tRNAs, rare codons are usually decoded by lowly-represented tRNAs. Whether rare codons play a role in controlling the expression of lowly- or temporarily-expressed proteins is an open question. In this work we approached this question using two strategies, either by replacing rare glycine codons with optimal counterparts in the gene that encodes the cell cycle protein Cdc13, or by overexpression the tRNA Gly that decodes rare codons from the fission yeast, Schizosaccharomyces pombe. While the replacement of synonymous codons severely affected cell growth, increasing tRNA levels affected the aggregation status of Cdc13 and cell division. These lead us to think that rare codons in lowly-expressed cyclin proteins are crucial for cell division, and that the overexpression of tRNA that decodes rare codons affects the expression of proteins containing these rare codons. These codons may be the result of the natural selection of codons in genes that encode lowly-expressed proteins.

10.
Vaccine ; 38(51): 8175-8184, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33162204

RESUMO

Bacterial surface lipoproteins are emerging as attractive vaccine candidates due to their biological importance and the feasibility of their large-scale production for vaccine manufacturing. The global prevalence of gonorrhea, resistance to antibiotics, and serious consequences to reproductive and neonatal health necessitate development of effective vaccines. Reverse vaccinology identified the surface-displayed L-methionine binding lipoprotein MetQ (NGO2139) and its homolog GNA1946 (NMB1946) as gonococcal and meningococcal vaccine candidates, respectively. Here, we assessed the suitability of MetQ for inclusion in a gonorrhea vaccine by examining MetQ conservation, its function inNeisseria gonorrhoeae (Ng) pathogenesis, and its ability to induce protective immune responses using a female murine model of lower genital tract infection. In-depth bioinformatics, phylogenetics and mapping the most prevalent Ng polymorphic amino acids to the GNA1946 crystal structure revealed remarkable MetQ conservation: ~97% Ng isolates worldwide possess a single MetQ variant. Mice immunized with rMetQ-CpG (n = 40), a vaccine containing a tag-free version of MetQ formulated with CpG, exhibited robust, antigen-specific antibody responses in serum and at the vaginal mucosae including IgA. Consistent with the activity of CpG as a Th1-stimulating adjuvant, the serum IgG1/IgG2a ratio of 0.38 suggested a Th1 bias. Combined data from two independent challenge experiments demonstrated that rMetQ-CpG immunized mice cleared infection faster than control animals (vehicle, p < 0.0001; CpG, p = 0.002) and had lower Ng burden (vehicle, p = 0.03; CpG, p < 0.0001). We conclude rMetQ-CpG induces a protective immune response that accelerates bacterial clearance from the murine lower genital tract and represents an attractive component of a gonorrhea subunit vaccine.


Assuntos
Gonorreia , Vacinas Meningocócicas , Animais , Vacinas Bacterianas/genética , Feminino , Gonorreia/prevenção & controle , Lipoproteínas/genética , Camundongos , Camundongos Endogâmicos BALB C , Neisseria gonorrhoeae/genética
11.
Rev. urug. cardiol ; 38(1): e301, 2023. ilus, tab
Artigo em Espanhol | BNUY, UY-BNMED, LILACS | ID: biblio-1442150

RESUMO

La amiloidosis cardíaca es una miocardiopatía restrictiva infiltrativa secundaria al depósito extracelular de amiloide. Las diferentes técnicas de imagen cardíaca permiten la evaluación de forma no invasiva. El ecocardiograma juega un rol central en la evaluación diagnóstica, pronóstica y ayuda a guiar el tratamiento. El objetivo de este artículo de revisión es describir las diferentes herramientas que nos brinda la ecocardiografía, poniendo énfasis en el strain por speckle tracking y describir su rol en el diagnóstico de esta patología.


Cardiac amyloidosis is an infiltrative restrictive cardiomyopathy secondary to extracellular amyloid deposition. Different cardiac imaging techniques allow noninvasive evaluation. Echocardiography plays a central role in diagnostic and prognostic evaluation and helps to guide treatment. The aim of this review is to describe the different tools provided by echocardiography, with emphasis on speckle tracking strain and to describe its role in the diagnosis of this pathology.


A amiloidose cardíaca é uma cardiomiopatia restritiva infiltrativa secundária ao depósito de amiloide extracelular. Diferentes técnicas de imagem cardíaca permitem fazer uma análise não invasiva. A ecocardiografia desempenha um papel central no diagnóstico e na avaliação prognóstica e ajuda a orientar o tratamento. O objetivo deste artigo de revisão é descrever as diferentes ferramentas proporcionadas pela ecocardiografia, com ênfase no strain por speckle tracking, e descrever o seu papel no diagnóstico desta patologia.


Assuntos
Ecocardiografia Doppler/métodos , Cardiopatias/diagnóstico por imagem , Amiloidose/diagnóstico por imagem , Prognóstico , Sensibilidade e Especificidade , Ecocardiografia Transesofagiana/métodos
12.
Appl Radiat Isot ; 140: 238-246, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30071415

RESUMO

An onshore radiometric survey sampled in situ the isotopes U238, Th232, K40, and Rn222 to build maps of normalized values for each element containing negative and positive radiometric anomalies, which could associate with hydrocarbon deposits in the subsoil. The vertical migration of hydrocarbon, water or other gases would have generated the different isotope anomalies. In four 2D seismic sections of the study area, three on dip direction and another in strike direction, we interpreted unconformities, flooding surface, and maximum flooding surfaces, as well as Cretaceous tops. In structural contour maps made from aforementioned seismic sections, we observe structural highs and structures such as truncations of strata. These structures in-depth coincide with uranium, thorium, potassium and radon anomalies seen on the surface. This oil and gas exploration approach that integrates radiometric and emanometric integrated with seismic prospecting can help to reduce the risk in hydrocarbons projects (however, radiometric anomalies are not uniquely associated with hydrocarbons). This work shows a correlation between radiometric (uranium, thorium, and potassium) and emanometric (radon) data in the surface with structures in the subsurface suck like truncation, that could present hydrocarbon, however, on this sub-basin, there has not been found commercial hydrocarbon.

13.
Front Immunol ; 9: 2793, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30564232

RESUMO

Expanding efforts to develop preventive gonorrhea vaccines is critical because of the serious health consequences combined with the prevalence and the dire possibility of untreatable gonorrhea. Reverse vaccinology, which includes genome and proteome mining, has proven successful in the discovery of vaccine candidates against many pathogenic bacteria. Here, we describe proteomic applications including comprehensive, quantitative proteomic platforms and immunoproteomics coupled with broad-ranging bioinformatics that have been applied for antigen mining to develop gonorrhea vaccine(s). We further focus on outlining the vaccine candidate decision tree, describe the structure-function of novel proteome-derived antigens as well as ways to gain insights into their roles in the cell envelope, and underscore new lessons learned about the fascinating biology of Neisseria gonorrhoeae.


Assuntos
Antígenos/imunologia , Vacinas Bacterianas/imunologia , Gonorreia/imunologia , Proteoma/imunologia , Animais , Membrana Celular/imunologia , Biologia Computacional/métodos , Humanos , Neisseria gonorrhoeae/imunologia , Proteômica/métodos , Relação Estrutura-Atividade
14.
Sci Rep ; 8(1): 14900, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297853

RESUMO

ß-lactam antibiotics, such as penicillin share a very unstable chemical structure. In water-based solutions, such as those used for clinical applications, the ß-lactam ring is readily opened due to a nucleophilic or electrophilic attack, leading to the loss of antimicrobial activity. Since the achievement and maintenance of optimum therapeutic levels of ß-lactam antibiotics is critical for the resolution of many infectious clinical situations, and to avoid antibiotic resistance generation, the design of new non-aqueous dosage forms is urgent. Recently, natural deep eutectic solvents (NADES) have emerged as alternative non-toxic and non-aqueous solvents for different biomedical applications. In this work, we formulated and characterized a NADES composed by betaine and urea (BU). Using this solvent, we evaluated the stability of clavulanic acid (CLV) and imipenem (IMP) and characterized their antimicrobial activities calculating the minimal inhibitory concentration. Characterization of BU solvent by infrared spectroscopy (IR) and nuclear magnetic resonance spectroscopy (NMR) indicated that the obtained solvent has a microstructure mainly based on hydrogen bonding interactions and water addition strongly affects its dynamic. The stability of ß-lactam antibiotic IMP and CLV using this solvent was increased by 7 fold and 2.5 fold respectively compared to water when analysed seven days after being dissolved. Microbiological assays showed that antibacterial activity at day seven was significantly decreased for both CLV and IMP when dissolved in water, while no change in their antibacterial properties was observed when antibiotics were dissolved in BU. The increased stability of IMP and CLV in BU may be related to the inert behaviour of the solvent and the higher dynamic restriction that helps antibiotics to maintain a more stable conformation. These data suggest the potential use of BU as a solvent to prevent degradation of ß-lactam antibiotics.


Assuntos
Antibacterianos/farmacologia , Solventes/química , beta-Lactamas/farmacologia , Betaína/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Ácido Clavulânico/farmacologia , Escherichia coli/efeitos dos fármacos , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Pseudomonas aeruginosa/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Ureia/química , Vibração , Água/química
16.
Medwave ; 16(5): e6480, 2016 Jun 28.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27392141

RESUMO

We describe a 71-year-old male patient who developed acute myocardial infarction (AMI) due to a dynamic left ventricular outflow tract obstruction induced by terazosin. After receiving terazosin, the patient had a syncope followed by angina. The electrocardiogram showed Q waves and ST segment elevation in the precordial and inferior leads. Coronary angiography evidenced a chronically occluded left anterior descending artery. Doppler-echocardiography revealed apical akinesia, hyperdynamic basal segments, systolic anterior motion of the mitral valve (SAM) and dynamic left ventricular outflow tract obstruction. Therapy with intravenous fluids and atenolol resulted in marked clinical improvement. Acute myocardial infarction resulted from low coronary perfusion pressure in a patient with a chronically diminished coronary reserve.


Describimos el caso de un hombre de 71 años de edad, que presentó un infarto agudo de miocardio debido a la obstrucción dinámica del tracto de salida del ventrículo izquierdo inducida por la terazosina. Luego de recibir dicha medicación el paciente presentó un síncope y posteriormente angina de pecho. El electrocardiograma evidenció ondas Q y sobreelevación del segmento ST en las derivaciones precordiales e inferiores. La angiografía coronaria evidenció una oclusión crónica de la arteria descendente anterior y el ecocardiograma Doppler reveló aquinesia apical, segmentos basales hiperdinámicos, movimiento anterior sistólico de la válvula mitraI y obstrucción dinámica del tracto de salida del ventrículo izquierdo. La administración intravenosa de suero fisiológico y atenolol determinó una clara mejoría clínica. Un infarto agudo de miocardio hemodinámico fue el resultado de la caída de la presión de perfusión coronaria en un paciente con disminución crónica de la reserva coronaria.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/efeitos adversos , Cardiomiopatias/complicações , Infarto do Miocárdio/induzido quimicamente , Prazosina/análogos & derivados , Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Idoso , Angina Pectoris/induzido quimicamente , Angiografia Coronária , Ecocardiografia Doppler , Humanos , Masculino , Infarto do Miocárdio/etiologia , Prazosina/administração & dosagem , Prazosina/efeitos adversos , Síncope/induzido quimicamente , Obstrução do Fluxo Ventricular Externo/induzido quimicamente , Obstrução do Fluxo Ventricular Externo/complicações
17.
Rev. urug. cardiol ; 36(3): e702, 2021. ilus
Artigo em Espanhol | LILACS, UY-BNMED, BNUY | ID: biblio-1367083

RESUMO

La hernia hiatal es una entidad relativamente frecuente y puede ser un hallazgo incidental en un estudio ecocardiográfico. Describimos el caso de una paciente con diagnóstico de masa en la aurícula izquierda (AI) sin clara etiología, a quien se le realiza el diagnóstico de hernia hiatal por resonancia magnética cardíaca (RMC) y luego se demuestra mediante ecocardiografía de contraste el contenido gástrico de la masa tras la ingestión de una bebida carbonatada, lo que permite de forma rápida y sencilla aclarar el diagnóstico.


Hiatal hernia is a relatively common entity, and may be an incidental finding in an echocardiographic study. We describe the case of a patient with a diagnosis of a mass in the left atrium with no clear etiology, in whom the diagnosis of hiatal hernia is made by cardiac magnetic resonance imaging and then demonstrated by contrast echocardiography the gastric content of the mass after the ingestion of a carbonated drink, which allows quickly and easily to clarify the diagnosis.


A hérnia de hiato é uma entidade relativamente comum, e pode ser um achado incidental em um estudo ecocardiográfico. Descrevemos o caso de um paciente com diagnóstico de massa em átrio esquerdo sem etiologia definida, em que o diagnóstico de hérnia de hiato é feito por ressonância magnética cardíaca e posteriormente demonstrado por ecocardiografia contrastada com uma bebida gaseificada, permitindo esclarecer de forma rápida e fácil o diagnóstico.


Assuntos
Humanos , Feminino , Idoso , Cardiopatias/diagnóstico por imagem , Hérnia Hiatal/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tamponamento Cardíaco/diagnóstico por imagem , Ecocardiografia Doppler , Diagnóstico Diferencial , Imagem Multimodal , Água Carbonatada , Átrios do Coração/diagnóstico por imagem
18.
Phytopathology ; 95(6): 692-700, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18943786

RESUMO

ABSTRACT Change in relative frequencies of the three main genetic types of Botrytis cinerea (Group I, Group II vacuma, and Group II transposa) were monitored over time from 1998 to 2000 in three Bordeaux vineyards not treated with fungicides. During 2000, Group I isolates, detected mostly at flowering comprised only 2.5% of the entire population. Within Group II, the complementary frequencies of vacuma and transposa isolates differed significantly depending on grapevine phenological stages and organs. Every year and at all sites, including one noble rot site, transposa isolates dominated at every stage, particularly on overwintering canes and at harvest (greater than 86.7% on berries). The complementary frequency of vacuma isolates reached a maximum on senescing floral caps (between 23.5 and 71.4%) and then decreased significantly until harvest on leaves and berries. In pathogenicity tests on grape berries, transposa isolates were significantly more virulent than were vacuma isolates. Mycelial growth rate was negatively correlated with virulence, notably on leaves in transposa and with double resistance to the fungicides carbendazim and vinclozolin. In vacuma, this double resistance was positively correlated with virulence on leaves. Change in the vacuma and transposa frequencies was most likely caused by differences in saprotrophic and pathogenic fitness. Possible interactions between fungicide resistance profiles and fitness are discussed.

19.
Medwave ; 15(9): e6285, 2015 Oct 16.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26523696

RESUMO

A proper characterization of frequency-dependent bundle branch blocks can provide useful prognostic information in some clinical situations. Often, this physiological event may be due to an extensive damage of infrahisian system, which poses a high risk of developing advanced atrioventricular block requiring pacemaker implantation. We describe the case of a 62 year-old man with chronic ischemic heart disease who exhibited alternating tachycardia-dependent bundle branch block during stress test. We discuss the main prognostic implications of this unusual event in the context of systolic dysfunction.


Una caracterización correcta de los bloqueos de rama dependientes de frecuencia, puede proporcionar información relevante en ciertas situaciones clínicas. A menudo, este evento fisiológico puede evidenciar la presencia de un daño extenso del sistema de conducción infrahisiano con riesgo elevado de bloqueo aurículo-ventricular avanzado y necesidad de implante de marcapasos. Describimos el caso de un hombre de 62 años con cardiopatía isquémica crónica, que exhibió un bloqueo de rama bilateral alternante taquicardia-dependiente durante el esfuerzo ergométrico, discutiendo las principales implicancias pronósticas de este evento inusual en el contexto de la disfunción sistólica.


Assuntos
Bloqueio de Ramo/fisiopatologia , Isquemia Miocárdica/fisiopatologia , Taquicardia/fisiopatologia , Bloqueio de Ramo/diagnóstico , Teste de Esforço , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Sístole , Taquicardia/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia
20.
Sci Rep ; 5: 9138, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25774962

RESUMO

The nanoarchitecture and micromachinery of a cell can be leveraged to fabricate sophisticated cell-driven devices. This requires a coherent strategy to derive cell's mechanistic abilities, microconstruct, and chemical-texture towards such microtechnologies. For example, a microorganism's hydrophobic membrane encapsulating hygroscopic constituents allows it to sustainably withhold a high aquatic pressure. Further, it provides a rich surface chemistry available for nano-interfacing and a strong mechanical response to humidity. Here we demonstrate a route to incorporate a complex cellular structure into microelectromechanics by interfacing compatible graphene quantum dots (GQDs) with a highly responsive single spore microstructure. A sensitive and reproducible electron-tunneling width modulation of 1.63 nm within a network of GQDs chemically-secured on a spore was achieved via sporal hydraulics with a driving force of 299.75 Torrs (21.7% water at GQD junctions). The electron-transport activation energy and the Coulomb blockade threshold for the GQD network were 35 meV and 31 meV, respectively; while the inter-GQD capacitance increased by 1.12 folds at maximum hydraulic force. This is the first example of nano/bio interfacing with spores and will lead to the evolution of next-generation bio-derived microarchitectures, probes for cellular/biochemical processes, biomicrorobotic-mechanisms, and membranes for micromechanical actuation.


Assuntos
Grafite/química , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Pontos Quânticos/química , Esporos Bacterianos
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