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1.
J Microsc ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963095

RESUMO

Flow or collective movement is a frequently observed phenomenon for many cellular components including the cytoskeletal proteins actin and myosin. To study protein flow in living cells, we and others have previously used spatiotemporal image correlation spectroscopy (STICS) analysis on fluorescence microscopy image time series. Yet, in cells, multiple protein flows often occur simultaneously on different scales resulting in superimposed fluorescence intensity fluctuations that are challenging to separate using STICS. Here, we exploited the characteristic that distinct protein flows often occur at different spatial scales present in the image series to disentangle superimposed protein flow dynamics. We employed a newly developed and an established spatial filtering algorithm to alternatively accentuate or attenuate local image intensity heterogeneity across different spatial scales. Subsequently, we analysed the spatially filtered time series with STICS, allowing the quantification of two distinct superimposed flows within the image time series. As a proof of principle of our analysis approach, we used simulated fluorescence intensity fluctuations as well as time series of nonmuscle myosin II in endothelial cells and actin-based podosomes in dendritic cells and revealed simultaneously occurring contiguous and noncontiguous flow dynamics in each of these systems. Altogether, this work extends the application of STICS for the quantification of multiple protein flow dynamics in complex biological systems including the actomyosin cytoskeleton.

2.
Eur Spine J ; 32(3): 1054-1067, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36609887

RESUMO

INTRODUCTION: Surgical decompression is standard care in the treatment of degenerative spondylolisthesis in patients with symptomatic lumbar spinal stenosis, but there remains controversy over the benefits of adding fusion. The persistent lack of consensus on this matter and the availability of new data warrants a contemporary systematic review and meta-analysis of the literature. METHODS: Multiple online databases were systematically searched up to October 2022 for randomized controlled trials (RCTs) and prospective studies comparing outcomes of decompression alone versus decompression with fusion for lumbar spinal stenosis in patients with degenerative spondylolisthesis. Primary outcome was the Oswestry Disability Index. Secondary outcomes included leg and back pain, surgical outcomes, and radiological outcomes. Pooled effect estimates were calculated and presented as mean differences (MD) with their 95% confidence intervals (CI) at two-year follow-up. RESULTS: Of the identified 2403 studies, eventually five RCTs and two prospective studies were included. Overall, most studies had a low or unclear risk of selection bias and most studies were focused on low grade degenerative spondylolisthesis. All patient-reported outcomes showed low statistical heterogeneity. Overall, there was high-quality evidence suggesting no difference in functionality at two years of follow-up (MD - 0.31, 95% CI - 3.81 to 3.19). Furthermore, there was high-quality evidence of no difference in leg pain (MD - 1.79, 95% CI - 5.08 to 1.50) or back pain (MD - 2.54, 95% CI - 6.76 to 1.67) between patients undergoing decompression vs. decompression with fusion. Pooled surgical outcomes showed less blood loss after decompression only, shorter length of hospital stay, and a similar reoperation rate compared to decompression with fusion. CONCLUSION: Based on the current literature, there is high-quality evidence of no difference in functionality after decompression alone compared to decompression with fusion in patients with degenerative lumbar spondylolisthesis at 2 years of follow-up. Further studies should focus on long-term comparative outcomes, health economic evaluations, and identifying those patients that may benefit more from decompression with fusion instead of decompression alone. This review was registered at Prospero (CRD42021291603).


Assuntos
Fusão Vertebral , Estenose Espinal , Espondilolistese , Humanos , Estenose Espinal/complicações , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/cirurgia , Espondilolistese/complicações , Espondilolistese/diagnóstico por imagem , Espondilolistese/cirurgia , Fusão Vertebral/efeitos adversos , Resultado do Tratamento , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Dor nas Costas/etiologia , Descompressão
3.
Telemed J E Health ; 29(12): 1834-1842, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37126940

RESUMO

Objective: Low- and middle-income countries (LMICs) face many challenges compared to industrialized nations, most notably in regard to the health care system. Patients often have to travel long distances to receive medical care with few reliable transportation mechanisms. In time-critical emergencies, this is a significant disadvantage. One specialty that is particularly affected by this is spine surgery. Within this field, traumatic injuries and acutely compressive pathologies are often time-critical. Increasing global networking capabilities through internet access offers the possibility for telemedical support in remote regions. Recently, high-performance cameras and processors became available in commercially available smartphones. Due to their wide availability and ease of use, this could provide a unique opportunity to offer telemedical support in LMICs. Methods: We conducted a feasibility study with a neurosurgical institution in east Africa. To ensure telemedical support, a commercially available smartphone was selected as the experimental hardware. Preoperatively, resolution, contrast, brightness, and color reproduction were assessed under theoretical conditions using a test chart. Intraoperatively, the image quality was assessed under different conditions. In the first step, the instrumentation table was displayed, and the mentor surgeon marked an instrument that the mentee surgeon should recognize correctly. In the next evaluation step, the surgical field was shown on film and the mentor surgeon marked an anatomical structure, and in the last evaluation step, the screen of the X-ray machine was captured, and the mentor surgeon again marked an anatomical structure. Subjective image quality was rated by two independent reviewers using the similar modified Likert scale as before on a scale of 1-5, with 1 indicating inadequate quality and 5 indicating excellent quality. Results: The image quality during the video calls was rated as sufficient overall. When evaluating the test charts, a quality of 97% ± 5 on average was found for the chart with the white background and a quality of 84% ± 5 on average for the chart with the black background. The color reproduction, the contrast, and the reproduction of brightness were rated excellent. Intraoperatively, the visualization of the instrument table was also rated excellent. Visualization of the operative site was rated 1.5 ± 0.5 on average and it was not possible to recognize relevant anatomical structures with the required confidence for surgical procedures. Image quality of the X-ray screen was rated 1.5 ± 0.9 on average. Conclusion: Current generation smartphones have high imaging performance, high computing power, and excellent connectivity. However, relevant anatomical structures during spine surgery procedures and on the X-ray screen in the operating room could not be identified with reliability to provide adequate surgical support. Nevertheless, our study showed the potential in smartphones supporting surgical procedures in LMICs, which could be helpful in other surgical fields.


Assuntos
Cirurgiões , Telemedicina , Humanos , Smartphone , Países em Desenvolvimento , Reprodutibilidade dos Testes
4.
Entropy (Basel) ; 25(4)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37190475

RESUMO

In recent years, chaotic synchronization has received a lot of interest in applications in different fields, including in the design of private and secure communication systems. The purpose of this paper was to achieve the synchronization of the Méndez-Arellano-Cruz-Martínez (MACM) 3D chaotic system coupled in star topology. The MACM electronic circuit is used as chaotic nodes in the communication channels to achieve synchronization in the proposed star network; the corresponding electrical hardware in the slave stages receives the coupling signal from the master node. In addition, a novel application to the digital image encryption process is proposed using the coupled-star-network; and the switching parameter technique is finally used to transmit an image as an encrypted message from the master node to the slave coupled nodes. Finally, the cryptosystem is submitted to statistical tests in order to show the effectiveness in multi-user secure image applications.

5.
Entropy (Basel) ; 25(5)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37238464

RESUMO

In this paper, synchronization and encrypted communication transmissions of analog and digital messages in a deterministic small-world network (DSWN) are presented. In the first instance, we use a network with 3 coupled nodes in a nearest-neighbor (NN) topology, then the amount of nodes is increased until reaching a DSWN with 24 nodes. The synchronization and encrypted communication transmissions using a DSWN are presented experimentally by using Chua's chaotic circuit as node, in both analog and digital electronic implementations, where for the continuous version (CV) we use operational amplifiers (OA), and in the discretized version (DV) we use Euler's numerical algorithm implemented in an embedded system by using an Altera/Intel FPGA and external digital-to-analog converters.

6.
Neurosurg Focus ; 52(6): E4, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35921190

RESUMO

OBJECTIVE: Telemedicine technology has been developed to allow surgeons in countries with limited resources to access expert technical guidance during surgical procedures. The authors report their initial experience using state-of-the-art wearable smart glasses with wireless capability to transmit intraoperative video content during spine surgery from sub-Saharan Africa to experts in the US. METHODS: A novel smart glasses system with integrated camera and microphone was worn by a spine surgeon in Dar es Salaam, Tanzania, during 3 scoliosis correction surgeries. The images were transmitted wirelessly through a compatible software system to a computer viewed by a group of fellowship-trained spine surgeons in New York City. Visual clarity was determined using a modified Snellen chart, and a percentage score was determined on the smallest line that could be read from the 8-line chart on white and black backgrounds. A 1- to 5-point scale (from 1 = unrecognizable to 5 = optimal clarity) was used to score other visual metrics assessed using a color test card including hue, contrast, and brightness. The same scoring system was used by the group to reach a consensus on visual quality of 3 intraoperative points including instruments, radiographs (ability to see pedicle screws relative to bony anatomy), and intraoperative surgical field (ability to identify bony landmarks such as transverse processes, pedicle screw starting point, laminar edge). RESULTS: All surgeries accomplished the defined goals safely with no intraoperative complications. The average download and upload connection speeds achieved in Dar es Salaam were 45.21 and 58.89 Mbps, respectively. Visual clarity with the modified white and black Snellen chart was 70.8% and 62.5%, respectively. The average scores for hue, contrast, and brightness were 2.67, 3.33, and 2.67, respectively. Visualization quality of instruments, radiographs, and intraoperative surgical field were 3.67, 1, and 1, respectively. CONCLUSIONS: Application of smart glasses for telemedicine offers a promising tool for surgical education and remote training, especially in low- and middle-income countries. However, this study highlights some limitations of this technology, including optical resolution, intraoperative lighting, and internet connection challenges. With continued collaboration between clinicians and industry, future iterations of smart glasses technology will need to address these issues to stimulate robust clinical utilization.


Assuntos
Óculos Inteligentes , Países em Desenvolvimento , Estudos de Viabilidade , Humanos , Coluna Vertebral/cirurgia , Tanzânia
7.
PLoS Pathog ; 14(8): e1007199, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089172

RESUMO

Clostridium difficile is a Gram-positive spore-former bacterium and the leading cause of nosocomial antibiotic-associated diarrhea that can culminate in fatal colitis. During the infection, C. difficile produces metabolically dormant spores, which persist in the host and can cause recurrence of the infection. The surface of C. difficile spores seems to be the key in spore-host interactions and persistence. The proteome of the outermost exosporium layer of C. difficile spores has been determined, identifying two cysteine-rich exosporium proteins, CdeC and CdeM. In this work, we explore the contribution of both cysteine-rich proteins in exosporium integrity, spore biology and pathogenesis. Using targeted mutagenesis coupled with transmission electron microscopy we demonstrate that both cysteine rich proteins, CdeC and CdeM, are morphogenetic factors of the exosporium layer of C. difficile spores. Notably, cdeC, but not cdeM spores, exhibited defective spore coat, and were more sensitive to ethanol, heat and phagocytic cells. In a healthy colonic mucosa (mouse ileal loop assay), cdeC and cdeM spore adherence was lower than that of wild-type spores; while in a mouse model of recurrence of the disease, cdeC mutant exhibited an increased infection and persistence during recurrence. In a competitive infection mouse model, cdeC mutant had increased fitness over wild-type. Through complementation analysis with FLAG fusion of known exosporium and coat proteins, we demonstrate that CdeC and CdeM are required for the recruitment of several exosporium proteins to the surface of C. difficile spores. CdeC appears to be conserved exclusively in related Peptostreptococcaeace family members, while CdeM is unique to C. difficile. Our results sheds light on how CdeC and CdeM affect the biology of C. difficile spores and the assembly of the exosporium layer and, demonstrate that CdeC affect C. difficile pathogenesis.


Assuntos
Proteínas de Bactérias/metabolismo , Clostridioides difficile/patogenicidade , Infecções por Clostridium/metabolismo , Esporos Bacterianos/metabolismo , Animais , Proteínas de Bactérias/química , Parede Celular/química , Parede Celular/metabolismo , Clostridioides difficile/química , Clostridioides difficile/metabolismo , Cisteína/química , Cisteína/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Camundongos , Esporos Bacterianos/química
8.
Psychosomatics ; 61(1): 39-48, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31611047

RESUMO

BACKGROUND: Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis causes substantial neurological disability. Autoantibodies causing encephalitis directed against the neuronal cell surface or synapse are of diagnostic importance giving the possibility of successful immunotherapy. OBJECTIVE: In this study, we aim to provide supporting evidence that brain 18F-FDG-PET may be helpful in identifying likely patterns of regional brain glucose metabolism. METHODS: Thirty-three patients (18 men and 15 women; age range of 17-55 y) with positive NMDA receptor antibody encephalitis that underwent an 18F-FDG-PET imaging examination were prospectively selected and compared with a reference group of 14 brain 18F-FDG-PET scans from healthy volunteers using voxel-based statistical analysis. Clusters of hyper- and hypo-metabolism were reported for the whole sample of patients (FWE-corrected P < 0.05), and uncorrected at P < 0.005 for a group of relapsed patients. RESULTS: Mixed metabolic patterns (focal/bilateral hypermetabolism in the temporal lobe, insula, and cerebellum; associated with severe bilateral hypometabolism in the occipital and parietal lobes) were found. CONCLUSIONS: Our findings suggest that 18F-FDG-PET should be included as an imaging tool when assessing affected patients in the clinical workup to rule out anti-NMDA encephalitis and help determine the most effective treatment.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Adolescente , Adulto , Encefalite Antirreceptor de N-Metil-D-Aspartato/metabolismo , Encefalite Antirreceptor de N-Metil-D-Aspartato/fisiopatologia , Afasia/fisiopatologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Catatonia/fisiopatologia , Cerebelo/diagnóstico por imagem , Cerebelo/metabolismo , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Delírio/fisiopatologia , Eletroencefalografia , Feminino , Fluordesoxiglucose F18 , Alucinações/fisiopatologia , Humanos , Letargia/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Transtornos da Memória/fisiopatologia , Memória de Curto Prazo , Pessoa de Meia-Idade , Transtornos dos Movimentos/fisiopatologia , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/metabolismo , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/metabolismo , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/metabolismo , Adulto Jovem
9.
Int J Mol Sci ; 21(18)2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32933117

RESUMO

Clostridioides difficile is a Gram-positive, spore-forming bacterium that causes a severe intestinal infection. Spores of this pathogen enter in the human body through the oral route, interact with intestinal epithelial cells and persist in the gut. Once germinated, the vegetative cells colonize the intestine and produce toxins that enhance an immune response that perpetuate the disease. Therefore, spores are major players of the infection and ideal targets for new therapies. In this context, spore surface proteins of C. difficile, are potential antigens for the development of vaccines targeting C. difficile spores. Here, we report that the C-terminal domain of the spore surface protein BclA3, BclA3CTD, was identified as an antigenic epitope, over-produced in Escherichia coli and tested as an immunogen in mice. To increase antigen stability and efficiency, BclA3CTD was also exposed on the surface of B. subtilis spores, a mucosal vaccine delivery system. In the experimental conditions used in this study, free BclA3CTD induced antibody production in mice and attenuated some C. difficile infection symptoms after a challenge with the pathogen, while the spore-displayed antigen resulted less effective. Although dose regimen and immunization routes need to be optimized, our results suggest BclA3CTD as a potentially effective antigen to develop a new vaccination strategy targeting C. difficile spores.


Assuntos
Proteínas de Bactérias/imunologia , Clostridioides difficile/imunologia , Enterocolite Pseudomembranosa/imunologia , Imunoglobulina G/imunologia , Mucosa Nasal/imunologia , Esporos Bacterianos/imunologia , Animais , Antígenos/imunologia , Bacillus subtilis/imunologia , Enterocolite Pseudomembranosa/microbiologia , Epitopos/imunologia , Feminino , Imunização/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mucosa Nasal/microbiologia , Vacinação/métodos
10.
Int J Mol Sci ; 21(4)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32074955

RESUMO

Clostridioides difficile, formerly known as Clostridium difficile, is a spore-forming bacterium considered as the most common cause of nosocomial infections in developed countries. The spore of C. difficile is involved in the transmission of the pathogen and in its first interaction with the host; therefore, a therapeutic approach able to control C. difficile spores would improve the clearance of the infection. The C-terminal (CTD) end of BclA2, a spore surface protein of C. difficile responsible of the interaction with the host intestinal cells, was selected as a putative mucosal antigen. The BclA2 fragment, BclA2CTD, was purified and used to nasally immunize mice both as a free protein and after adsorption to the spore of Bacillus subtilis, a well-established mucosal delivery vehicle. While the adsorption to spores increased the in vitro stability of BclA2CTD, in vivo both free and spore-adsorbed BclA2CTD were able to induce a similar, specific humoral immune response in a murine model. Although in the experimental conditions utilized the immune response was not protective, the induction of specific IgG indicates that free or spore-bound BclA2CTD could act as a putative mucosal antigen targeting C. difficile spores.


Assuntos
Proteínas de Bactérias/imunologia , Clostridioides difficile/metabolismo , Imunidade Humoral , Administração Intranasal , Adsorção , Animais , Bacillus subtilis/fisiologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Células CACO-2 , Clostridioides difficile/patogenicidade , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/veterinária , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Domínios Proteicos/imunologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Esporos Bacterianos/química , Esporos Bacterianos/fisiologia
11.
BMC Bioinformatics ; 20(1): 565, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718537

RESUMO

BACKGROUND: Biologically data-driven networks have become powerful analytical tools that handle massive, heterogeneous datasets generated from biomedical fields. Protein-protein interaction networks can identify the most relevant structures directly tied to biological functions. Functional enrichments can then be performed based on these structural aspects of gene relationships for the study of channelopathies. Channelopathies refer to a complex group of disorders resulting from dysfunctional ion channels with distinct polygenic manifestations. This study presents a semi-automatic workflow using protein-protein interaction networks that can identify the most relevant genes and their biological processes and pathways in channelopathies to better understand their etiopathogenesis. In addition, the clinical manifestations that are strongly associated with these genes are also identified as the most characteristic in this complex group of diseases. RESULTS: In particular, a set of nine representative disease-related genes was detected, these being the most significant genes in relation to their roles in channelopathies. In this way we attested the implication of some voltage-gated sodium (SCN1A, SCN2A, SCN4A, SCN4B, SCN5A, SCN9A) and potassium (KCNQ2, KCNH2) channels in cardiovascular diseases, epilepsies, febrile seizures, headache disorders, neuromuscular, neurodegenerative diseases or neurobehavioral manifestations. We also revealed the role of Ankyrin-G (ANK3) in the neurodegenerative and neurobehavioral disorders as well as the implication of these genes in other systems, such as the immunological or endocrine systems. CONCLUSIONS: This research provides a systems biology approach to extract information from interaction networks of gene expression. We show how large-scale computational integration of heterogeneous datasets, PPI network analyses, functional databases and published literature may support the detection and assessment of possible potential therapeutic targets in the disease. Applying our workflow makes it feasible to spot the most relevant genes and unknown relationships in channelopathies and shows its potential as a first-step approach to identify both genes and functional interactions in clinical-knowledge scenarios of target diseases. METHODS: An initial gene pool is previously defined by searching general databases under a specific semantic framework. From the resulting interaction network, a subset of genes are identified as the most relevant through the workflow that includes centrality measures and other filtering and enrichment databases.


Assuntos
Canalopatias/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Anotação de Sequência Molecular , Mapas de Interação de Proteínas , Bases de Dados Genéticas , Redes Reguladoras de Genes , Humanos
12.
Xenotransplantation ; 26(3): e12507, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30963648

RESUMO

INTRODUCTION: Recent immunological and transgenic advances are a promising alternative using limited materials of human origin for transplantation. However, it is essential to achieve social acceptance of this therapy. OBJECTIVE: To analyze the attitude of nursing students from Spanish universities toward organ xenotransplantation (XTx) and to determine the factors affecting their attitude. MATERIALS AND METHODS: Type of study: A sociological, multicentre, and observational study. STUDY POPULATION: Nursing students enrolled in Spain (n = 28,000). SAMPLE SIZE: A sample of 10 566 students estimating a proportion of 76% (99% confidence and precision of ±1%), stratified by geographical area and year of study. Instrument of measurement: A validated questionnaire (PCID-XenoTx-RIOS) was handed out to every student in a compulsory session. This survey was self-administered and self-completed voluntarily and anonymously by each student in a period of 5-10 min. STATISTICAL ANALYSIS: descriptive analysis, Student's t test, the chi-square test, and a logistic regression analysis. RESULTS: A completion rate: 84% (n = 8913) was obtained. If the results of XTx were as good as in human donation, 74% (n = 6564) would be in favor and 22% (n = 1946) would have doubts. The following variables affected this attitude: age (P < 0.001); sex (P < 0.001); geographical location (P < 0.001); academic year of study (P < 0.001); attitude toward organ donation (P < 0.001); belief in the possibility of needing a transplant (P < 0.001); discussion of transplantation with one's family (P < 0.001) and friends (P < 0.001); and the opinion of one's partner (P < 0.001). The following variables persisted in the multivariate analysis: being a male (OR = 1.436; P < 0.001); geographical location (OR = 1.937; P < 0.001); an attitude in favor of donation (OR = 1.519; P < 0.001); belief in the possibility of needing a transplant (OR = 1.497; P = 0.036); and having spoken about the issue with family (OR = 1.351; P < 0.001) or friends (OR = 1.240; P = 0.001). CONCLUSIONS: The attitude of nursing students toward organ XTx is favorable and is associated with factors of general knowledge about organ donation and transplantation and social interaction.


Assuntos
Atitude , Transplante de Órgãos , Estudantes de Enfermagem/estatística & dados numéricos , Transplante Heterólogo , Feminino , Xenoenxertos/imunologia , Humanos , Doadores Vivos , Masculino , Transplante de Órgãos/métodos , Estudantes de Medicina , Obtenção de Tecidos e Órgãos/métodos
13.
Pediatr Transplant ; 23(8): e13595, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31571392

RESUMO

TDM of tacrolimus is usually performed with trough levels (C0h ). However, in pediatric patients, C0h may not be an adequate marker. The AUC is considered a more suitable indicator of drug exposure. As several blood samples are needed for the estimation of AUC, and LSS for predicting tacrolimus AUC and optimizing the dose adjustment have been proposed. Moreover, in emerging countries such as Mexico, non-innovator formulations, which bioequivalence has not been demonstrated, are frequently used. Hence, the aim of this study was to develop and validate a LSS to predict the tacrolimus AUC0-12h in Mexican pediatric kidney transplant recipients who received either Prograf® or non-innovator tacrolimus formulations. A total of 56 pharmacokinetic profiles were randomized into two groups: model development (n = 28) and model validation (n = 28). The limited sampling equations were obtained after a stepwise multiple regression using AUC as the dependent variable and tacrolimus blood concentrations, quantified by CMIA, at different time points as the independent variables. The final equation included observed concentrations at 1 hour (C1h ) and 4 hours (C4h ) after dose administration. The predictive performance of the model was adequate in terms of both, bias and precision. Results strongly suggest that the clinical use of this LSS could provide an ethical, cost-, and time-effective method in the TDM of tacrolimus in pediatric patients with kidney transplant. The model proved to be adequate with either Prograf® or non-innovator tacrolimus formulations of dubious bioequivalence.


Assuntos
Área Sob a Curva , Imunossupressores/farmacocinética , Transplante de Rim , Tacrolimo/farmacocinética , Adolescente , Animais , Bovinos , Criança , Pré-Escolar , Estudos Transversais , Previsões , Humanos , Masculino , México , Estudos Retrospectivos , Adulto Jovem
14.
Pediatr Dev Pathol ; 22(2): 157-160, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30322346

RESUMO

Image-guided percutaneous core needle biopsy is a standard and safe procedure for the diagnosis of both solid and hematological malignancies in children. Despite recent improvements, nondiagnosis biopsies persist. Lipoblastoma is a benign adipocytic tumor composed of embryonal fat admixed with mature adipocytes and occurring before the age of 1 year in one-third of cases. Lipoblastoma is usually easily diagnosed, but in some cases, diagnosis may be difficult on percutaneous biopsies, when the lipoblastic component is not well represented or when the tumor contains a prominent myxoid component mimicking other myxoid tumors. We report here a case of lipoblastoma with a predominant myxoid component and discuss differential diagnosis of myxoid lesions of infancy. In such cases, pathologic examination enhanced by adjunct techniques, such as immunohistochemistry and cytogenetic or molecular genetic studies, is needed to achieve accurate diagnosis, particularly on fine-needle biopsies.


Assuntos
Lipoblastoma/patologia , Biópsia por Agulha Fina , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Lipoblastoma/diagnóstico
15.
Rev Med Chil ; 146(1): 22-31, 2018 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-29806674

RESUMO

BACKGROUND: Sedentary behaviors are one of the major risk factors for cardiovascular diseases. AIM: To identify factors associated with high sedentary behaviors in the Chilean population. MATERIAL AND METHODS: We included 5,040 participants from the Chilean National Health Survey 2009-2010. Physical activity level and sedentary behavior (sitting time) were measured using the Global Physical Activity Questionnaire (GPAQ v2). Highly sedentary behaviors were determined as > 4 hours per day of sitting time. Logistic regression was used to identify correlates of highly sedentary behavior. RESULTS: Forty seven percent of the study population reported spending more than 4 hours per day sitting. The prevalence was higher in women. The main factors associated with high sedentary behavior were: high income levels (Odds ratio (OR):1.91 [95% Confidence intervals (CI:1.61-2.27]); being woman (OR:1.39 [95% CI:1.24-1.56]): having central obesity (OR:1.15 [95% CI:1.02-1.30]), being physically inactive (OR:2.35 [95% CI:2.06-2.68]), and living in an urban area (OR:1.92 [95% CI:1.63-2.26]). Other factors associates with high sedentary behavior were: being smoker, having a television set, computer and private car at their homes. Participants reporting a poor self-reported health and wellbeing and those with diabetes or metabolic syndrome were more likely to be highly sedentary. CONCLUSIONS: The main factors associated with high levels of sedentary behavior are socio-demographic issues, lifestyles and health status.


Assuntos
Exercício Físico , Atividade Motora , Comportamento Sedentário , Adulto , Idoso , Índice de Massa Corporal , Chile , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Fatores Socioeconômicos , Inquéritos e Questionários , População Urbana
16.
J Nanobiotechnology ; 15(1): 1, 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-28049488

RESUMO

BACKGROUND: Nanotechnology is a science that involves imaging, measurement, modeling and a manipulation of matter at the nanometric scale. One application of this technology is drug delivery systems based on nanoparticles obtained from natural or synthetic sources. An example of these systems is synthetized from poly(3-hydroxybutyrate-co-3-hydroxyvalerate), which is a biodegradable, biocompatible and a low production cost polymer. The aim of this work was to investigate the uptake mechanism of PHBV nanoparticles in two different epithelial cell lines (HeLa and SKOV-3). RESULTS: As a first step, we characterized size, shape and surface charge of nanoparticles using dynamic light scattering and transmission electron microscopy. Intracellular incorporation was evaluated through flow cytometry and fluorescence microscopy using intracellular markers. We concluded that cellular uptake mechanism is carried out in a time, concentration and energy dependent way. Our results showed that nanoparticle uptake displays a cell-specific pattern, since we have observed different colocalization in two different cell lines. In HeLa (Cervical cancer cells) this process may occur via classical endocytosis pathway and some internalization via caveolin-dependent was also observed, whereas in SKOV-3 (Ovarian cancer cells) these patterns were not observed. Rearrangement of actin filaments showed differential nanoparticle internalization patterns for HeLa and SKOV-3. Additionally, final fate of nanoparticles was also determined, showing that in both cell lines, nanoparticles ended up in lysosomes but at different times, where they are finally degraded, thereby releasing their contents. CONCLUSIONS: Our results, provide novel insight about PHBV nanoparticles internalization suggesting that for develop a proper drug delivery system is critical understand the uptake mechanism.


Assuntos
Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos , Nanopartículas/metabolismo , Neoplasias/tratamento farmacológico , Poliésteres/metabolismo , Transporte Biológico , Linhagem Celular Tumoral , Endocitose , Células HeLa , Humanos , Nanopartículas/ultraestrutura
17.
Eur Spine J ; 26(2): 389-396, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27272621

RESUMO

PURPOSE: Tubular laminotomy is an effective procedure for treatment of lumbar spinal stenosis (LSS) and lateral recesses stenosis. Most surgeons familiar with the procedure agree that the tubular approach appears to afford a more complete decompression of the contralateral thecal sac and nerve root, as compared to the ipsilateral approach. With this study we sought to answer the question whether this is reflected in clinically significant differences between the ipsilateral and contralateral side pain improvements. METHODS: In a retrospective case study, patients with LSS and lateral recesses stenosis who started out with VAS scores that were similar on the right and left side were included. All patients underwent a tubular (MIS) "over the top" laminotomy from a unilateral approach and through one incision. Surgeries were performed by a single surgeon in a single center. At the last follow-up, the extent of VAS score improvement on the approach (ipsilateral) side was compared to that of the contralateral side. RESULTS: Thirty-three patients were included in. At the latest follow-up of 25.8 ± 3.4 months, there were statistically significant improvements in ODI and back VAS scores (p = 0.002 and p < 0.0001, respectively). In addition, buttock VAS scores were significantly improved both on the ipsilateral and the contralateral side (p < 0.001, and p = 0.001, respectively). Similarly, leg VAS scores were improved significantly on both sides (p < 0.001, and p = 0.001, respectively). There were no statistically significant differences between the extent of pain improvement on the ipsilateral and the contralateral side. CONCLUSIONS: MIS tubular laminotomy through a unilateral approach results in clinically effective bilateral decompression of LSS and lateral recesses, regardless of the approach side.


Assuntos
Laminectomia/métodos , Vértebras Lombares/cirurgia , Dor/cirurgia , Estenose Espinal/cirurgia , Escala Visual Analógica , Idoso , Avaliação da Deficiência , Feminino , Humanos , Masculino , Dor/etiologia , Estudos Retrospectivos
18.
Arterioscler Thromb Vasc Biol ; 35(1): 184-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25414254

RESUMO

OBJECTIVES: Critical limb ischemia complicates peripheral artery disease leading to tissue damage and amputation. We hypothesized that modifying adipose stromal cells (ASCs) to overexpress human vascular endothelial growth factor 165 (VEGF) would limit ischemic muscle damage to a larger extent than nonmodified ASCs. APPROACH AND RESULTS: Rabbits with critical hindlimb ischemia were injected with allogeneic abdominal fat-derived ASCs transfected with plasmid-VEGF165 (ASCs-VEGF; n=10). Additional rabbits received nontransfected ASCs (ASCs; n=10) or vehicle (placebo; n=10). One month later, ASCs-VEGF rabbits exhibited significantly higher density of angiographically visible collaterals and capillaries versus placebo (both P<0.05) but not versus ASCs (both P=NS). Arteriolar density, however, was increased in both ASCs and ASCs-VEGF groups (both P<0.05 versus placebo). ASCs-VEGF and ASCs showed comparable post-treatment improvements in Doppler-assessed peak systolic velocity, blood pressure ratio, and resistance index. Ischemic lesions were found in 40% of the muscle samples in the placebo group, 19% in the ASCs-VEGF group, and 17% in the ASCs groups (both P<0.05 versus placebo, Fisher test). CONCLUSIONS: In a rabbit model of critical limb ischemia, intramuscular injection of ASCs genetically modified to overexpress VEGF increase angiographically visible collaterals and capillary density. However, both modified and nonmodified ASCs increase arteriolar density to a similar extent and afford equal protection against ischemia-induced muscle lesions. These results indicate that modifying ASCs to overexpress VEGF does not enhance the protective effect of ASCs, and that arteriolar proliferation plays a pivotal role in limiting the irreversible tissue damage of critical limb ischemia.


Assuntos
Tecido Adiposo/transplante , Terapia Genética/métodos , Isquemia/terapia , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica , Células Estromais/transplante , Fator A de Crescimento do Endotélio Vascular/biossíntese , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Arteríolas/metabolismo , Arteríolas/fisiopatologia , Velocidade do Fluxo Sanguíneo , Capilares/metabolismo , Capilares/fisiopatologia , Células Cultivadas , Circulação Colateral , Modelos Animais de Doenças , Feminino , Membro Posterior , Humanos , Isquemia/genética , Isquemia/metabolismo , Isquemia/patologia , Isquemia/fisiopatologia , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Necrose , Coelhos , Recuperação de Função Fisiológica , Fluxo Sanguíneo Regional , Células Estromais/metabolismo , Fatores de Tempo , Transfecção , Fator A de Crescimento do Endotélio Vascular/genética
19.
Res Sports Med ; 24(3): 281-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27357919

RESUMO

Although all authors report beneficial health changes following training based on the Pilates method, no explicit analysis has been performed of its cardiorespiratory effects. The objective of this study was to evaluate possible changes in cardiorespiratory parameters with the Pilates method. A total of 45 university students aged 18-35 years (77.8% female and 22.2% male), who did not routinely practice physical exercise or sports, volunteered for the study and signed informed consent. The Pilates training was conducted over 10 weeks, with three 1-hour sessions per week. Physiological cardiorespiratory responses were assessed using a MasterScreen CPX apparatus. After the 10-week training, statistically significant improvements were observed in mean heart rate (135.4-124.2 beats/min), respiratory exchange ratio (1.1-0.9) and oxygen equivalent (30.7-27.6) values, among other spirometric parameters, in submaximal aerobic testing. These findings indicate that practice of the Pilates method has a positive influence on cardiorespiratory parameters in healthy adults who do not routinely practice physical exercise activities.


Assuntos
Adaptação Fisiológica , Técnicas de Exercício e de Movimento , Condicionamento Físico Humano/fisiologia , Adolescente , Adulto , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Consumo de Oxigênio , Troca Gasosa Pulmonar , Espirometria , Adulto Jovem
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