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1.
Nat Mater ; 22(7): 867-872, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37349399

RESUMO

The emergence of a topological transition of the polaritonic dispersion in twisted bilayers of anisotropic van der Waals materials at a given twist angle-the photonic magic angle-results in the diffractionless propagation of polaritons with deep-subwavelength resolution. This type of propagation, generally referred to as canalization, holds promise for the control of light at the nanoscale. However, the existence of a single photonic magic angle hinders such control since the canalization direction in twisted bilayers is unique and fixed for each incident frequency. Here we overcome this limitation by demonstrating multiple spectrally robust photonic magic angles in reconfigurable twisted α-phase molybdenum trioxide (α-MoO3) trilayers. We show that canalization of polaritons can be programmed at will along any desired in-plane direction in a single device with broad spectral ranges. These findings open the door for nanophotonics applications where on-demand control is crucial, such as thermal management, nanoimaging or entanglement of quantum emitters.


Assuntos
Fótons , Anisotropia
2.
Metabolomics ; 20(2): 22, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347235

RESUMO

INTRODUCTION: For many samples studied by GC-based metabolomics applications, extensive sample preparation involving extraction followed by a two-step derivatization procedure of methoximation and trimethylsilylation (TMS) is typically required to expand the metabolome coverage. Performing normalization is critical to correct for variations present in samples and any biases added during the sample preparation steps and analytical runs. Addressing the totality of variations with an adequate normalization method increases the reliability of the downstream data analysis and interpretation of the results. OBJECTIVES: Normalizing to sample mass is one of the most commonly employed strategies, while the total peak area (TPA) as a normalization factor is also frequently used as a post-acquisition technique. Here, we present a new normalization approach, total derivatized peak area (TDPA), where data are normalized to the intensity of all derivatized compounds. TDPA relies on the benefits of silylation as a universal derivatization method for GC-based metabolomics studies. METHODS: Two sample classes consisting of systematically incremented sample mass were simulated, with the only difference between the groups being the added amino acid concentrations. The samples were TMS derivatized and analyzed using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC × GC-TOFMS). The performance of five normalization strategies (no normalization, normalized to sample mass, TPA, total useful peak area (TUPA), and TDPA) were evaluated on the acquired data. RESULTS: Of the five normalization techniques compared, TUPA and TDPA were the most effective. On PCA score space, they offered a clear separation between the two classes. CONCLUSION: TUPA and TDPA carry different strengths: TUPA requires peak alignment across all samples, which depends upon the completion of the study, while TDPA is free from the requirement of alignment. The findings of the study would enhance the convenient and effective use of data normalization strategies and contribute to overcoming the data normalization challenges that currently exist in the metabolomics community.


Assuntos
Metaboloma , Metabolômica , Metabolômica/métodos , Reprodutibilidade dos Testes , Cromatografia Gasosa-Espectrometria de Massas/métodos
3.
Phytochem Anal ; 35(5): 1134-1141, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38520203

RESUMO

INTRODUCTION: Olive oil, derived from the olive tree (Olea europaea L.), is used in cooking, cosmetics, and soap production. Due to its high value, some producers adulterate olive oil with cheaper edible oils or fraudulently mislabel oils as olive to increase profitability. Adulterated products can cause allergic reactions in sensitive individuals and can lack compounds which contribute to the perceived health benefits of olive oil, and its corresponding premium price. OBJECTIVE: There is a need for robust methods to rapidly authenticate olive oils. By utilising machine learning models trained on the nuclear magnetic resonance (NMR) spectra of known olive oil and edible oils, samples can be classified as olive and authenticated. While high-field NMRs are commonly used for their superior resolution and sensitivity, they are generally prohibitively expensive to purchase and operate for routine screening purposes. Low-field benchtop NMR presents an affordable alternative. METHODS: We compared the predictive performance of partial least squares discrimination analysis (PLS-DA) models trained on low-field 60 MHz benchtop proton (1H) NMR and high-field 400 MHz 1H NMR spectra. The data were acquired from a sample set consisting of 49 extra virgin olive oils (EVOOs) and 45 other edible oils. RESULTS: We demonstrate that PLS-DA models trained on low-field NMR spectra are highly predictive when classifying EVOOs from other oils and perform comparably to those trained on high-field spectra. We demonstrated that variance was primarily driven by regions of the spectra arising from olefinic protons and ester protons from unsaturated fatty acids in models derived from data at both field strengths.


Assuntos
Azeite de Oliva , Espectroscopia de Prótons por Ressonância Magnética , Azeite de Oliva/química , Análise dos Mínimos Quadrados , Espectroscopia de Prótons por Ressonância Magnética/métodos , Óleos de Plantas/química , Óleos de Plantas/análise , Espectroscopia de Ressonância Magnética/métodos , Olea/química
4.
Metabolomics ; 19(8): 74, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37566260

RESUMO

INTRODUCTION: Fecal samples are highly complex and heterogeneous, containing materials at various stages of digestion. The heterogeneity and complexity of feces make stool metabolomics inherently challenging. The level of homogenization influences the outcome of the study, affecting the metabolite profiles and reproducibility; however, there is no consensus on how fecal samples should be prepared to overcome the topographical discrepancy and obtain data representative of the stool as a whole. OBJECTIVES: Various combinations of homogenization conditions were compared to investigate the effects of bead size, addition of solvents and the differences between wet-frozen and lyophilized feces. METHODS: The homogenization parameters were systematically altered to evaluate the solvent usage, bead size, and whether lyophilization is required in homogenization. The metabolic coverage and reproducibility were compared among the different conditions. RESULTS: The current work revealed that a combination of mechanical and chemical lysis obtained by bead-beating with a mixture of big and small sizes of beads in an organic solvent is an effective way to homogenize fecal samples with adequate reproducibility and metabolic coverage. Lyophilization is required when bead-beating is not available. CONCLUSIONS: A comprehensive and systematical evaluation of various fecal matter homogenization conditions provides a profound understanding for the effects of different homogenization methods. Our findings would be beneficial to assist with standardization of fecal sample homogenization protocol.


Assuntos
Metaboloma , Metabolômica , Metabolômica/métodos , Reprodutibilidade dos Testes , Fezes , Solventes
5.
Adv Exp Med Biol ; 1438: 203-207, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37845462

RESUMO

Cerebral veins have received increasing attention due to their importance in preoperational planning and the brain oxygenation measurement. There are different modalities to image those vessels, such as magnetic resonance angiography (MRA) and recently, contrast-enhanced (CE) 3D gradient-echo sequences. However, the current techniques have certain disadvantages, i.e., the long examination time, the requirement of contrast agents or inability to measure oxygenation. Near-infrared optical tomography (NIROT) is emerging as a viable new biomedical imaging modality that employs near infrared light (650-950 nm) to image biological tissue. It was proven to easily penetrate the skull and therefore enables the brain vessels to be assessed. NIROT utilizes safe non-ionizing radiation and can be applied in e.g., early detection of neonatal brain injury and ischemic strokes. The aim is to develop non-invasive label-free dynamic time domain (TD) NIROT to image the brain vessels. A simulation study was performed with the software (NIRFAST) which models light propagation in tissue with the finite element method (FEM). Both a simple shape mesh and a real head mesh including all the segmented vessels from MRI images were simulated using both FEM and a hybrid FEM-U-Net network, we were able to visualize the superficial vessels with NIROT with a Root Mean Square Error (RMSE) lower than 0.079.


Assuntos
Cabeça , Tomografia Óptica , Humanos , Recém-Nascido , Simulação por Computador , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Software , Tomografia Óptica/métodos
6.
Metabolomics ; 18(4): 25, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35426515

RESUMO

INTRODUCTION: Feces is a highly complex matrix containing thousands of metabolites. It also contains live bacteria and enzymes, and does not have a static chemistry. Consequently, proper control of pre-analytical parameters is critical to minimize unwanted variations in the samples. However, no consensus currently exists on how fecal samples should be stored/processed prior to analysis. OBJECTIVE: The effects of sample handling conditions on fecal metabolite profiles and abundances were examined using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOFMS). METHODS: Solid-phase microextraction (SPME) and derivatization via trimethylsilylation (TMS) were employed as complementary techniques to evaluate fresh, frozen, and lyophilized fecal samples with expanded coverage of the fecal metabolome. The total number of detected peaks and the signal intensities were compared among the different handling conditions. RESULTS: Our analysis revealed that the metabolic profiles of fecal samples depend greatly on sample handling and processing conditions, which had a more pronounced effect on results obtained by SPME than by TMS derivatization. Overall, lyophilization resulted in a greater amount of total and class-specific metabolites, which may be attributed to cell lysis and/or membrane disintegration. CONCLUSIONS: A comprehensive comparison of the sample handling conditions provides a deeper understanding of the physicochemical changes that occur within the samples during freezing and lyophilization. Based on our results, snap-freezing at -80 °C would be preferred over lyophilization for handling samples in the field of fecal metabolomics as this imparts the least change from the fresh condition.


Assuntos
Metabolômica , Microextração em Fase Sólida , Fezes/química , Congelamento , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metabolômica/métodos , Microextração em Fase Sólida/métodos
7.
Environ Sci Technol ; 56(11): 7143-7152, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35522906

RESUMO

Microbial volatile organic compounds (MVOCs) play an essential role in many environmental fields, such as indoor air quality. Long-term exposure to odorous and toxic MVOCs can negatively affect the health of occupants. Recently, the involvement of surface reservoirs in indoor chemistry has been realized, which signifies the importance of the phase partitioning of volatile organic pollutants. However, reliable partition coefficients of many MVOCs are currently lacking. Equilibrium partition coefficients, such as Henry's law constant, H, are crucial for understanding the environmental behavior of chemicals. This study aims to experimentally determine the H values and their temperature dependence for key MVOCs under temperature relevant to the indoor environment. The H values were determined with the inert gas-stripping (IGS) method and variable phase ratio headspace (VPR-HS) technique. A two-dimensional partitioning model was applied to predict the indoor phase distribution of MVOCs and potential exposure pathways to the residences. The findings show that the MVOCs are likely distributed between the gas and weakly polar (e.g., organic-rich) reservoirs indoors. Temperature and the volume of reservoirs can sensitively affect indoor partitioning. Our results give a more comprehensive view of indoor chemical partitioning and exposure.


Assuntos
Poluição do Ar em Ambientes Fechados , Compostos Orgânicos Voláteis , Poluição do Ar em Ambientes Fechados/análise , Temperatura , Compostos Orgânicos Voláteis/química
8.
Adv Exp Med Biol ; 1395: 199-204, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36527637

RESUMO

Diffused light imaging techniques, such as near-infrared optical tomography (NIROT), require a stable platform for testing and validation that imitates tissue optical properties. The aim of this work was to build a robust, but flexible liquid phantom for BORL time-domain NIROT system Pioneer. The phantom was designed to assess penetration depth and resolution of the system, and to provide a heterogeneous inner structure that can be changed in controllable manner with adjustable optical properties. We used only in-house produced 3D-printed elements and mechanics of a budget 3D-printer to build the phantom, and managed to keep the overall costs below $500. We achieved stable and repeatable movement of an arbitrary structure in 3+1 degree of freedom inside the phantom and demonstrated its performance in a series of tests. Thus, we presented a universal and cost-effective solution for testing NIROT, that can be easily customised to various systems or testing paradigms.


Assuntos
Tomografia Óptica , Análise Custo-Benefício , Imagens de Fantasmas
9.
Med Oral Patol Oral Cir Bucal ; 27(6): e525-e531, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36173719

RESUMO

BACKGROUND: The aim of this study was to validate and determine at pretest level the reliability of the Portuguese version of the Groningen radiotherapy-induced xerostomia questionnaire. MATERIAL AND METHODS: This study employed 37 head and neck cancer patients. Each patient signed an informed consent and responded to the Portuguese version of the questionnaire in the form of an interview. This was repeated again after 2 weeks. A standard single question provided a validity check. Data were analyzed using Cronbach's α to test its reliability and total and interitem correlation, and intraclass correlation to determine its internal consistency and test-retest reliability. Construct validity supported by objective measurements as salivary secretion was also investigated. Significance was set at .05. RESULTS: Cronbach's α was 0.91 and 0.89 for the first and second test administrations, respectively, which indicates that the internal consistency was excellent. The intraclass correlation coefficient value for the test-retest reliability was 0.70. The correlation between the total score of the questionnaire and standard single dry mouth question was 0.72 for the first round, indicating a good correlation. CONCLUSIONS: Demonstrating very good psychometric properties, the Portuguese version of the Groningen radiotherapy-induced xerostomia questionnaire is a valid tool and can be considered a reliable instrument to measure xerostomia in head and neck cancer patients.


Assuntos
Neoplasias de Cabeça e Pescoço , Xerostomia , Humanos , Reprodutibilidade dos Testes , Portugal , Xerostomia/diagnóstico , Xerostomia/etiologia , Inquéritos e Questionários , Psicometria , Neoplasias de Cabeça e Pescoço/radioterapia
10.
Eur Cell Mater ; 41: 40-51, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33411938

RESUMO

The repair of focal cartilage defects remains one of the foremost issues in the field of orthopaedics. Chondral defects may arise from a variety of joint pathologies and left untreated, will likely progress to osteoarthritis. Current repair techniques, such as microfracture, result in short-term clinical improvements but have poor long-term outcomes. Emerging scaffold-based repair strategies have reported superior outcomes compared to microfracture and motivate the development of new biomaterials for this purpose. In this study, unique composite implants consisting of a base porous reinforcing component (woven poly(ε-caprolactone)) infiltrated with 1 of 2 hydrogels (self-assembling peptide or thermo-gelling hyaluronan) or bone marrow aspirate were evaluated. The objective was to evaluate cartilage repair with composite scaffold treatment compared to the current standard of care (microfracture) in a translationally relevant large animal model, the Yucatan minipig. While many cartilage-repair studies have shown some success in vivo, most are short term and not clinically relevant. Informed by promising 6-week findings, a 12-month study was carried out and those results are presented here. To aid in comparisons across platforms, several structural and functionally relevant outcome measures were performed. Despite positive early findings, the long-term results indicated less than optimal structural and mechanical results with respect to cartilage repair, with all treatment groups performing worse than the standard of care. This study is important in that it brings much needed attention to the importance of performing translationally relevant long-term studies in an appropriate animal model when developing new clinical cartilage repair approaches.


Assuntos
Cartilagem Articular , Animais , Materiais Biocompatíveis , Cartilagem Articular/cirurgia , Modelos Animais de Doenças , Ácido Hialurônico , Suínos , Porco Miniatura
11.
J Endocrinol Invest ; 44(4): 713-723, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32734320

RESUMO

PURPOSE: Cold exposure activates the hypothalamus-pituitary-thyroid (HPT) axis, response blunted by previous acute stress or corticosterone administration. Chronic stressors can decrease serum T3 concentration, and thyrotropin-releasing hormone (Trh) expression in the paraventricular nucleus (PVN), but impact on the response to cold is unknown; this was studied in rats submitted to daily repeated restraint (rRes) that causes habituation of hypothalamus-pituitary-adrenal (HPA) axis response, or to chronic variable stress (CVS) that causes sensitization and hyperreactivity. METHODS: Wistar male adult rats were submitted to rRes 30 min/day, or to CVS twice a day, for 15 days. On day 16, rats were exposed 1 h to either 5 or 21 °C. Parameters of HPT and HPA axes activity and of brown adipose tissue (BAT) cold response were measured; gene expression in PVN and BAT, by RT-PCR; serum hormone concentration by radioimmunoassay or ELISA. RESULTS: Compared to naïve animals, Crh and corticosterone concentrations were attenuated at the end of rRes, but increased at the end of CVS treatments. Cold exposure increased mRNA levels of Crh, Trh, and serum concentration of thyrotropin in naïve, but not in rRes or CVS rats; corticosterone increased in all groups. Cold induced expression of thermogenic genes in BAT (Dio2 and Ucp1) in naïve but not in stressed rats; Adrb3 expression was differentially regulated. CONCLUSION: Both types of chronic stress blunted HPT and BAT responses to cold. Long-term stress effects on noradrenergic and/or hormonal signaling are likely responsible for HPT dysfunction and not the type of chronic stressor.


Assuntos
Tecido Adiposo Marrom/metabolismo , Resposta ao Choque Frio/fisiologia , Corticosterona , Sistema Hipotálamo-Hipofisário/metabolismo , Glândula Tireoide/metabolismo , Hormônio Liberador de Tireotropina/metabolismo , Animais , Corticosterona/sangue , Corticosterona/metabolismo , Regulação da Expressão Gênica , Iodeto Peroxidase/metabolismo , Masculino , Núcleo Hipotalâmico Paraventricular/metabolismo , Ratos , Ratos Wistar , Receptores Adrenérgicos beta 3/metabolismo , Estresse Fisiológico , Tempo , Proteína Desacopladora 1/metabolismo , Iodotironina Desiodinase Tipo II
12.
Adv Exp Med Biol ; 1269: 341-346, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33966240

RESUMO

The neonatal brain is a vulnerable organ, and lesions due to hemorrhage and/or ischemia occur frequently in preterm neonates. Even though neuroprotective therapies exist, there is no tool available to detect the ischemic lesions. To address this problem, we have recently designed and built the new time-domain near-infrared optical tomography (TD NIROT) system - Pioneer. Here we present the results of a phantom study of the system performance. We used silicone phantoms to mimic risky situations for brain lesions: hemorrhage and hypoxia. Employing Pioneer, we were able to reconstruct accurately both position and optical properties of these inhomogeneities.


Assuntos
Hipóxia Encefálica , Tomografia Óptica , Hemorragia , Humanos , Hipóxia , Recém-Nascido , Imagens de Fantasmas
13.
Adv Exp Med Biol ; 1269: 359-363, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33966243

RESUMO

In preterm infants, there is a risk of life-lasting impairments due to hemorrhagic/ischemic lesions. Our time-domain (TD) near-infrared optical tomography (NIROT) system "Pioneer" aims at detecting both disorders with high spatial resolution. Successfully tested on phantoms, "Pioneer" entered the phase of improvements and enhancements. The current probe (A-probe) was adapted for an optoacoustics instrument. A new probe (B-probe) optimized for TD measurements is required. Our aim is to determine the optimal arrangement of light sources in the B-probe to increase the sensitivity and the resolution of Pioneer and to improve the ability of the system to detect both ischemia and hemorrhage. To do this, we simulated TD-NIROT signals in NIRFAST, a MATLAB-based package used to model near-infrared light propagation through tissue. We used 16 × 16 detector array, with ~2.2 mm distance between the detectors. Light sources were arranged around the field of view (FoV). We performed forward simulations of light propagation through a "homogeneous case" (HC) tissue (µ's = 5.6 cm-1, µa = 0.07 cm-1). Next, we simulated light propagation through "inhomogeneous case" -tissue' (IC) tissue by adding ischemia (µa = µa · 2.5 cm-1) or hemorrhage (µa = µa · 50 cm-1) to HT as a spherical inclusion of 5 mm radius at different depths in the FoV center and identified the source location that provides the higher contrast on the FoV: maxi ∈ I (FoVContrastSOURCE). It was found that sources located closer to the FoV center generate greater contrast for late photons. This study suggests the light sources in B-probe should be closer to the FoV center. The higher sensitivity is expected to lead to a higher image quality.


Assuntos
Encéfalo , Recém-Nascido Prematuro , Encéfalo/diagnóstico por imagem , Diagnóstico por Imagem , Humanos , Recém-Nascido , Imagens de Fantasmas , Análise Espectral
14.
J Surg Res ; 255: 456-462, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32619861

RESUMO

BACKGROUND: The 5-factor modified frailty index (mFI-5) and the 11-factor modified frailty index (mFI-11) are equally effective in predicting adverse outcomes in the American College of Surgeons National Surgical Quality Improvement Program database. The similarly structured American College of Surgeons Trauma Quality Improvement Program (TQIP) database has not been studied with these two frailty indices. We hypothesized that the mFI-5 and mFI-11 could similarly predict adverse outcomes with TQIP data. METHODS: The mFI-5 and mFI-11 were calculated for each patient comprising our institutional TQIP registry (2016-2018). Spearman ρ was calculated to assess correlations between the two indices across multiple predefined TQIP patient cohorts. Complications were stratified by frailty score for each index. Multivariable logistic regression models adjusting for age, Glasgow Coma Scale score, and Injury Severity Score were created to assess each mFI's association with any complication and discharge dispositions (home, facility, and expired). RESULTS: There were 8467 patients. Spearman ρ was >0.9 (P < 0.0001) for all patient cohorts except elderly, elderly blunt multisystem, and isolated hip fractures. Increasing frailty scores for both mFIs were associated with greater rates of acute kidney injury (P < 0.0001), myocardial infarction (P < 0.001), severe sepsis (P < 0.05), unplanned return to the intensive care unit (P < 0.0001), and unplanned intubation (P < 0.0001). On separate multivariable logistic regressions, the mFI-5 and mFI-11 were each predictive of any complication (P < 0.0001) and a facility discharge (P < 0.001). Neither the mFI-5 nor the mFI-11 were associated with mortality (P > 0.05). CONCLUSIONS: The mFI-5 and mFI-11 are highly correlated across several TQIP patient cohorts. They also are both predictive of complications and discharge dispositions; however, neither index can predict mortality. Given its ease of use, the mFI-5 may be a better option for identifying frail patients and predicting adverse outcomes at the point of care in trauma.


Assuntos
Fragilidade/diagnóstico , Indicadores Básicos de Saúde , Sistema de Registros , Centros de Traumatologia , Ferimentos e Lesões/epidemiologia , Idoso , Comorbidade , Fragilidade/epidemiologia , Georgia/epidemiologia , Humanos , Melhoria de Qualidade , Estudos Retrospectivos
15.
Adv Exp Med Biol ; 1232: 347-354, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893430

RESUMO

In preterm infants, there is a risk of long-term cognitive, motor and behavioral impairments due to hemorrhagic and/or ischemic lesions. If detected early, lesions can be prevented. A bedside imaging modality, capable of early detection of both disorders, is necessary. We present the state of development of a tomographic imager (named Pioneer), that will be capable of determining the oxygenation of the preterm-infant brain with high spatial resolution. Pioneer is a time-resolved near-infrared optical tomography (TR NIROT) instrument. It employs multiple wavelength laser light in short pulses on 11 distinct locations and measures the re-emerging light in a contactless fashion by means of a time-correlated single-photon counting (TCSPC) camera (named Piccolo) covering ~4.9 cm2 with 300 detectors. Timing response of the entire system is 116 ps. An in-house designed biocompatible source ring ensures fixed relative positions of sources and detectors and provides a secure interface between the patient and the probe. At the present state, the NIROT Pioneer system successfully detected a 6x6x50 mm3 inclusion 3 cm deep inside a phantom. These results confirm that the Pioneer imager is working as expected and is on a solid path towards full 3D tissue oxygenation imaging.


Assuntos
Encéfalo , Recém-Nascido Prematuro , Oximetria , Oxigênio , Encéfalo/diagnóstico por imagem , Humanos , Recém-Nascido , Oximetria/instrumentação , Oximetria/métodos , Oximetria/normas , Oxigênio/metabolismo , Imagens de Fantasmas
16.
Gastroenterol Hepatol ; 43(8): 431-438, 2020 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32680732

RESUMO

AIM: To evaluate the efficacy and safety of endoscopic vacuum therapy (EVT) in the management of perforations and anastomotic leaks of the upper gastrointestinal tract. PATIENTS AND METHODS: This is a retrospective observational study which included patients who underwent EVT due to any upper gastrointestinal defect between April 2017 and February 2019 in three Spanish Hospitals. To this end, we used the only medical device approved to date for endoscopic use (Eso-SPONGEr; B. Braun Melsungen AG, Melsungen, Germany). RESULTS: 11 patients were referred for EVT of an anastomotic leak after esophagectomy (n=7), gastrectomy (n=2), esophageal perforation secondary to endoscopic Zenker's septomiotomy (n=1) and Boerhaave syndrome (n=1). The median size of the cavity was 8×3cm. The median delay between surgery and EVT was 7 days. The median of EVT duration was 28 days. The median number of sponges used was 7 and the mean period replacement was 3.7 days. In 10 cases (91%), the defect was successfully closed. In 9 cases (82%) clinical resolution of the septic condition was achieved. 5 patients presented some adverse event: 3 anastomotic strictures, 1 retropharyngeal pain and 1 case of new-onset pneumonia. The median hospital stay from the start of EVT was 45 days. 1 patient died owing to septic complications secondary to the anastomotic leak. CONCLUSION: EVT was successful in over 90% of perforations and anastomotic leaks of the upper gastrointestinal tract. Moreover, this is a safe therapy with only mild adverse events associated.


Assuntos
Fístula Anastomótica/cirurgia , Duodenopatias/cirurgia , Endoscopia Gastrointestinal , Perfuração Esofágica/cirurgia , Perfuração Intestinal/cirurgia , Tratamento de Ferimentos com Pressão Negativa/métodos , Ruptura Gástrica/cirurgia , Trato Gastrointestinal Superior/cirurgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tratamento de Ferimentos com Pressão Negativa/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
17.
Bull Environ Contam Toxicol ; 105(5): 758-763, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33068117

RESUMO

Cenotes are naturally occurring flooded caves that are frequent in Mexico's Yucatan Peninsula; they result from the collapse of limestone bedrock into the regional groundwater table. Cenotes in Quintana Roo are important ecological and economic hot spots but are susceptible to anthropogenic pollution. In this study, we collected water samples from 11 cenotes over multiple years to evaluate polycyclic aromatic hydrocarbon (PAH) concentrations and patterns as associated with tourist traffic. The primary PAHs detected in samples included fluoranthene, anthracene, phenanthrene and naphthalene, with total PAH concentrations increasing almost fivefold for cenotes sampled from 2016 to 2017. This is compared to only a 7% increase in tourist traffic during these years. Multivariate statistical analysis of the PAH concentration data suggests that diesel, gasoline and asphalt are the most likely pollution sources and that they are associated with periods of increased tourist traffic.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Água Subterrânea/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Região do Caribe , México , Análise de Componente Principal
18.
Int Endod J ; 52(11): 1556-1572, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31215045

RESUMO

BACKGROUND AND AIM: To perform a systematic review of anatomical studies using cone beam computed tomography (CBCT) to assess the influence of demographic factors (age, gender and geographic region) on the prevalence of C-shaped canal anatomy in maxillary molars, mandibular premolars and molars. DATA SOURCES: A search was conducted between May and August 2018 in four electronic databases and five peer-reviewed journals. The authors of included articles were also contacted for additional studies and the bibliographic references hand-searched. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS: The research protocol was previously registered in the International Prospective Register of Ongoing Systematic Reviews (CRD42018095201) and included defined inclusion/exclusion criteria. Prevalence studies on C-shaped canal anatomy in maxillary molars, mandibular premolars and molars were searched. STUDY APPRAISAL AND SYNTHESIS METHODS: The selected studies were submitted to full-text analysis and critical appraisal by two evaluators using the Joanna Briggs Institute Critical Appraisal tool. The final group of papers (n = 25) were pooled and forest plots with proportions and odds ratio with a 95% confidence interval performed. Meta-regression was undertaken to evaluate possible sources of heterogeneity and funnel plot visual analysis to assess publication bias. RESULTS: The included studies reported data on 25 445 teeth of 13 142 patients. A significant difference in the average prevalence proportion of C-shaped configuration was observed between mandibular first (0.3%; 0.1-0.6%) and second (12%; 10.3-13.7%) molars (P < 0.05). No significant difference in the prevalence of C-shaped configurations was observed comparing males (13.5%; 8.8-18.3%) and females (20.5%; 13.7-27.4%) in mandibular second molars (P > 0.05), although males were associated with significantly lower odds (0.573; 0.511-0.641) (P < 0.05). The pooled proportion of C-shaped anatomy in mandibular second molars in East Asian countries (39.6%; 36.0-43.1%) was significantly higher compared with other regions. LIMITATIONS: Because of the limited number of studies, no statistical analysis was performed for maxillary molars and mandibular premolars. CONCLUSION: Meta-analysis revealed that gender and geographic region may act as a confounding factor for the prevalence of C-shaped anatomy in mandibular second molars, whilst age did not influence the prevalence of C-shaped configurations in this tooth group. Knowing these preoperative factors would help to anticipate complex morphologies in clinics.


Assuntos
Cavidade Pulpar , Raiz Dentária , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Prevalência , Estudos Prospectivos
19.
Adv Exp Med Biol ; 1072: 165-169, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30178340

RESUMO

Oxygenation of a tumor is one of the most important predictive factors: hypoxia is associated with aggressive tumors and substantially lower survival rate. Despite this high relevance of tumor oxygenation, there is currently no bedside technique available to measure it in clinical routine care. The aim of this work is to determine the oxygenation of tissue in mice by a continuous wave multispectral near-infrared optical tomograph (mNIROT). Tomographic reconstructions were processed by a massively modified NIRFAST software. We quantitatively measured the tissue oxygen saturation of the tumors in 4 BALB/c nude, female mice with human colon carcinoma cancer cells DLD-1 KRASwt injected subcutaneously. The study revealed changes of oxygenation in tumors on the long-term.


Assuntos
Neoplasias Experimentais/irrigação sanguínea , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Tomografia Óptica/métodos , Hipóxia Tumoral/fisiologia , Animais , Linhagem Celular Tumoral , Feminino , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Consumo de Oxigênio/fisiologia
20.
J Urban Health ; 94(4): 525-533, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28656541

RESUMO

To guide targeted cessation and prevention programming, this study assessed smoking prevalence and described sociodemographic, health, and healthcare use characteristics of adult smokers in public housing. Self-reported data were analyzed from a random sample of 1664 residents aged 35 and older in ten New York City public housing developments in East/Central Harlem. Smoking prevalence was 20.8%. Weighted log-binomial models identified to be having Medicaid, not having a personal doctor, and using health clinics for routine care were positively associated with smoking. Smokers without a personal doctor were less likely to receive provider quit advice. While most smokers in these public housing developments had health insurance, a personal doctor, and received provider cessation advice in the last year (72.4%), persistently high smoking rates suggest that such cessation advice may be insufficient. Efforts to eliminate differences in tobacco use should consider place-based smoking cessation interventions that extend cessation support beyond clinical settings.


Assuntos
Serviços de Saúde/estatística & dados numéricos , Nível de Saúde , Pobreza/estatística & dados numéricos , Habitação Popular/estatística & dados numéricos , Fumar/epidemiologia , Adulto , Idoso , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , Prevalência , Fatores Socioeconômicos , População Urbana
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