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1.
Anal Chem ; 93(4): 2072-2081, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33393756

RESUMO

Effective and noninvasive cancer diagnosis is expected to ease the burden of continued increased deaths worldwide. Herein, we proposed viscosity of the tumor microenvironment as a biomarker and further develop a versatile optical agent, TBM-V, for monitoring tumor microenvironmental viscosity alterations to achieve cancer diagnosis, therapeutic effect tracking, and anticancer drug screening. When in highly viscous media, near-infrared signals of TBM-V are specifically activated, endowing the probe with the capacity of avoiding biological autofluorescence and achieving high signal-to-noise ratio imaging. The results of vascular imaging disclosed higher fluorescence of the blood vessels in the tumor than the normal ones, implying tumors being pointed out with brighter fluorescence. With the assistance of fluorescence imaging technology, TBM-V achieved noninvasively identifying cancer in vivo with high signal-to-noise ratio imaging. In addition, the capability of TBM-V to evaluate anticancer drug efficacy with viscosity as a robust biomarker was explored. Furthermore, as a proof of concept, screening of the anticancer drugs is also realized through in situ monitoring of the microenvironmental viscosity fluctuations of the tumor with TBM-V. Note that this proposed fluorescence imaging method outperforms the clinical hematoxylin and eosin (H&E) staining assay with the advantageous features of noninvasive and in vivo characteristics. We expected that this unique strategy will reinvigorate the continued perfection of the cancer diagnosis systems.


Assuntos
Corantes Fluorescentes/química , Neoplasias Mamárias Experimentais/diagnóstico , Espectrometria de Fluorescência/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Viscosidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Feminino , Corantes Fluorescentes/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Microambiente Tumoral
2.
Food Chem ; 334: 127614, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711282

RESUMO

Pectin polysaccharide is an important phytochemical with potential biomedical applications. It is commonly measured by time-consuming destructive chemical methods. This work demonstrates the feasibility of using visible and near-infrared hyperspectral imaging (HSI) techniques to rapidly measure pectin polysaccharides in intact mulberry fruits. Based on spatial information provided by HSI images, the representative spectrum of each whole mulberry was accurately extracted without background. The effects of storage temperature on two varieties of mulberries for model establishment were studied. The performances of two spectral ranges obtained by Si and InGaAs CCD detectors for pectin prediction were compared. The best predictions were obtained from dilute alkali soluble pectin and total soluble pectin in Dashi mulberry fruit stored at room temperature, with residual predictive deviation values of 2.317 and 1.935, respectively. Our results show that HSI is a promising alternative to the chemical method to rapidly and nondestructively measure the pectin content.


Assuntos
Análise de Alimentos/métodos , Frutas/química , Morus/química , Pectinas/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Armazenamento de Alimentos , Processamento de Imagem Assistida por Computador , Modelos Biológicos , Pectinas/química , Temperatura
3.
Food Chem ; 339: 128058, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32950900

RESUMO

To determine which cabbage head tissues are useful for evaluating freshness using spectroscopic technology, we stored wrapped and unwrapped cabbage heads for up to 30 d, and measured visible and near infrared spectra (420-2500 nm) of the 1st-10th leaf layers and cores. We found that spectral changes in leaves were affected both by leaf layer and storage conditions, while continuous spectral changes were observed in the cores regardless of storage condition. These spectral changes in the leaves and cores were consistent with color images and water content. While we developed good models for estimating the storage days from the 1st and 2nd leaf layers and the cores of unwrapped cabbages, only core spectra provided a high correlation with storage days in wrapped cabbages. These data demonstrated that the cabbage core is sensitive to storage duration and its spectra are useful for evaluating freshness decline regardless of storage condition.


Assuntos
Brassica/química , Qualidade dos Alimentos , Armazenamento de Alimentos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Cor , Análise de Alimentos/métodos , Folhas de Planta/química , Água/análise
4.
Nat Commun ; 11(1): 5355, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097705

RESUMO

Water and lipids are key participants in many biological processes, but there are few non-invasive methods that provide quantification of these components in vivo, and none that can isolate and quantify lipids in the blood. Here we develop a new imaging modality termed shortwave infrared meso-patterned imaging (SWIR-MPI) to provide label-free, non-contact, spatial mapping of water and lipid concentrations in tissue. The method utilizes patterned hyperspectral illumination to target chromophore absorption bands in the 900-1,300 nm wavelength range. We use SWIR-MPI to monitor clinically important physiological processes including edema, inflammation, and tumor lipid heterogeneity in preclinical models. We also show that SWIR-MPI can spatially map blood-lipids in humans, representing an example of non-invasive and contact-free measurements of in vivo blood lipids. Together, these results highlight the potential of SWIR-MPI to enable new capabilities in fundamental studies and clinical monitoring of major conditions including obesity, cancer, and cardiovascular disease.


Assuntos
Raios Infravermelhos , Lipídeos/sangue , Imagem Óptica/métodos , Ondas de Rádio , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Água/análise , Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Marrom/patologia , Adulto , Animais , Biomarcadores/sangue , Doenças Cardiovasculares/diagnóstico por imagem , Edema/diagnóstico por imagem , Edema/patologia , Feminino , Xenoenxertos , Humanos , Inflamação/diagnóstico por imagem , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Obesidade/diagnóstico por imagem , Imagem Óptica/instrumentação , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação
5.
Anesth Analg ; 131(5): 1444-1455, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33079868

RESUMO

Some neurological complications following surgery have been related to a mismatch in cerebral oxygen supply and demand that may either lead to more subtle changes of brain function or overt complications like stroke or coma. Discovery of a perioperative neurological complication may be outside the treatment window, thereby making prevention an important focus. Early commercial devices used differential spectroscopy to measure relative changes from baseline of 2 chromophores: oxy- and deoxyhemoglobin. It was the introduction of spatially resolved spectroscopy techniques that allowed near-infrared spectroscopy (NIRS)-based cerebral oximetry as we know it today. Modern cerebral oximeters measure the hemoglobin saturation of blood in a specific "optical field" containing arterial, capillary, and venous blood, not tissue oxygenation itself. Multiple cerebral oximeters are commercially available, all of which have technical differences that make them noninterchangeable. The mechanism and meaning of these measurements are likely not widely understood by many practicing physicians. Additionally, as with many clinically used monitors, there is a lack of high-quality evidence on which clinicians can base decisions in their effort to use cerebral oximetry to reduce neurocognitive complications after surgery. Therefore, the Sixth Perioperative Quality Initiative (POQI-6) consensus conference brought together an international team of multidisciplinary experts including anesthesiologists, surgeons, and critical care physicians to objectively survey the literature on cerebral oximetry and provide consensus, evidence-based recommendations for its use in accordance with the GRading of Recommendations, Assessment, Development and Evaluation (GRADE) criteria for evaluating biomedical literature. The group produced the following consensus recommendations: (1) interpreting perioperative cerebral oximetry measurements in the context of a preinduction baseline value; (2) interpreting perioperative cerebral oximetry measurements in the context of the physiologic variables that affect them; (3) using caution in comparing cerebral oximetry values between different manufacturers; (4) using preoperative cerebral oximetry to identify patients at increased risk of adverse outcomes after cardiac surgery; (5) using intraoperative cerebral oximetry indexed to preinduction baseline to identify patients at increased risk of adverse outcomes after cardiac surgery; (6) using cerebral oximetry to identify and guide management of acute cerebral malperfusion during cardiac surgery; (7) using an intraoperative cerebral oximetry-guided interventional algorithm to reduce intensive care unit (ICU) length of stay after cardiac surgery. Additionally, there was agreement that (8) there is insufficient evidence to recommend using intraoperative cerebral oximetry to reduce mortality or organ-specific morbidity after cardiac surgery; (9) there is insufficient evidence to recommend using intraoperative cerebral oximetry to improve outcomes after noncardiac surgery.


Assuntos
Período de Recuperação da Anestesia , Recuperação Pós-Cirúrgica Melhorada , Doenças do Sistema Nervoso/diagnóstico , Monitorização Neurofisiológica/métodos , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/diagnóstico , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Consenso , Humanos , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle
6.
Anesth Analg ; 131(5): 1520-1528, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33079875

RESUMO

BACKGROUND: Cerebral blood flow (CBF) is maintained over a range of blood pressures through cerebral autoregulation (CA). Blood pressure outside the range of CA, or impaired autoregulation, is associated with adverse patient outcomes. Regional oxygen saturation (rSO2) derived from near-infrared spectroscopy (NIRS) can be used as a surrogate CBF for determining CA, but existing methods require a long period of time to calculate CA metrics. We have developed a novel method to determine CA using cotrending of mean arterial pressure (MAP) with rSO2that aims to provide an indication of CA state within 1 minute. We sought to determine the performance of the cotrending method by comparing its CA metrics to data derived from transcranial Doppler (TCD) methods. METHODS: Retrospective data collected from 69 patients undergoing cardiac surgery with cardiopulmonary bypass were used to develop a reference lower limit of CA. TCD-MAP data were plotted to determine the reference lower limit of CA. The investigated method to evaluate CA state is based on the assessment of the instantaneous cotrending relationship between MAP and rSO2 signals. The lower limit of autoregulation (LLA) from the cotrending method was compared to the manual reference derived from TCD. Reliability of the cotrending method was assessed as uptime (defined as the percentage of time that the state of autoregulation could be measured) and time to first post. RESULTS: The proposed method demonstrated minimal mean bias (0.22 mmHg) when compared to the TCD reference. The corresponding limits of agreement were found to be 10.79 mmHg (95% confidence interval [CI], 10.09-11.49) and -10.35 mmHg (95% CI, -9.65 to -11.05). Mean uptime was 99.40% (95% CI, 99.34-99.46) and the mean time to first post was 63 seconds (95% CI, 58-71). CONCLUSIONS: The reported cotrending method rapidly provides metrics associated with CA state for patients undergoing cardiac surgery. A major strength of the proposed method is its near real-time feedback on patient CA state, thus allowing for prompt corrective action to be taken by the clinician.


Assuntos
Circulação Cerebrovascular , Homeostase , Monitorização Neurofisiológica Intraoperatória/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Pressão Arterial , Pressão Sanguínea , Ponte Cardiopulmonar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Estudos Retrospectivos , Ultrassonografia Doppler Transcraniana
7.
J Oleo Sci ; 69(11): 1373-1380, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33055436

RESUMO

According to CODEX, moisture and volatile matter are olive oil quality parameters and the development of a rapid screening method for the determination of moisture is of interest. We recently demonstrated for the first time that the weak near-infrared (NIR) band near 5260 cm-1 is primarily attributed to a water O-H combination band. To determine the intensity of this band, we measured the peak-to-peak (p-p) height of its first derivative and generated exponential calibration curves for p-p height versus gravimetrically determined concentrations of spiked water in olive oils that had been purged of their initial moisture contents. To further optimize this univariate calibration method, calibration curves were generated in the present study based on plotting the moisture band first derivative p-p heights for neat olive oils (that were neither purged nor spiked) versus the moisture concentrations obtained by the Karl-Fischer (KF) primary reference method. To enhance the speed of FT-NIR data collection, measurements were carried in the transmission mode using disposable glass tubes. We also developed and compared a multivariate partial least squares approach to the univariate one. All the spectra were collected in two separate laboratories using two FT-NIR spectrometers of the same brand and model and no significant difference (p > 0.05) was found between the two laboratory determinations and the KF reference values at a 95% confidence interval. High accuracies were found with the two FT-NIR instruments used, as indicated by the low root mean squared error (RMSE, %) for predicted values obtained with the univariate procedure (RMSE = 0.008% and 0.010%) and the multivariate one, which yielded an even lower value (RMSE= 0.007% for both instruments). These results suggest that, once validated, the FT-NIR approach could potentially be a rapid substitute for the KF method.


Assuntos
Análise de Alimentos/métodos , Qualidade dos Alimentos , Azeite de Oliva/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Água/análise , Calibragem , Sensibilidade e Especificidade
8.
PLoS One ; 15(9): e0238894, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915881

RESUMO

Quantitative analyses of soil and sediment samples are often used to complement stratigraphic interpretations in archaeological and geoscientific research. The outcome of such analyses often is confined to small parts of the examined profiles as only a limited number of samples can be extracted and processed. Recent laboratory studies show that such selectively measured soil and sediment characteristics can be spatially extrapolated using spectral image data, resulting in reliable maps of a variety of parameters. However, on-site usage of this method has not been examined. We therefore explore, whether image data (RGB data and visible and near infrared hyperspectral data), acquired under regular fieldwork conditions during an archaeological excavation, in combination with a sampling strategy that is close to common practice, can be used to produce maps of soil organic matter, hematite, calcite, several weathering indices and grain size characteristics throughout complex archaeological profiles. We examine two profiles from an archaeological trench in Yeha (Tigray, Ethiopia). Our findings show a promising performance of RGB data and its derivative CIELAB as well as hyperspectral data for the prediction of parameters via random forest regression. By including two individual profiles we are able to assess the accuracy and reproducibility of our results, and illustrate the advantages and drawbacks of a higher spectral resolution and the necessary additional effort during fieldwork. The produced maps of the parameters examined allow us to critically reflect on the stratigraphic interpretation and offer a more objective basis for layer delineation in general. Our study therefore promotes more transparent and reproducible documentation for often destructive archaeological fieldwork.


Assuntos
Arqueologia/métodos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Laboratórios/estatística & dados numéricos , Solo/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Etiópia , Reprodutibilidade dos Testes
9.
PLoS One ; 15(8): e0234979, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857778

RESUMO

The present meta-analysis was based on the available studies to determine the potential role of the initial and regional cerebral oxygen saturation (rSO2) in monitoring the efficiency of cardiopulmonary resuscitation (CPR) and predicting the return of spontaneous circulation (ROSC). Three electronic databases of PubMed, Embase, and the Cochrane Library were searched to identify the studies that investigated the role of rSO2 on ROSC in CA patients throughout May 2018. The weighted mean difference (WMD) with 95% confidence interval (CI) was calculated to estimate the pooled effect using a random-effects model. Sensitivity, subgroup analyses, and publication bias were conducted. A total of 13 studies involving 678 CA patients (300 in-hospital (IH) patients, and 378 out-hospital (OH) patients) were included. The summary WMD suggested that ROSC patients were associated with higher initial rSO2 (WMD: 10.10%; 95% CI: 5.66-14.55; P<0.001) and mean rSO2 (WMD: 14.16%; 95% CI: 10.51-17.81; P<0.001) levels during CA and ROSC as compared to the non-ROSC. The results of meta-regression suggested that the male percentage and the location of cardiac arrest might bias the initial or mean rSO2 and the incidence of ROSC. These significant differences were observed in nearly all subsets. The findings of this study suggested that high initial or mean rSO2 levels were both associated with an increased incidence of ROSC in CA patients undergoing CPR. These correlations might be affected by the percentage of males or the location of cardiac arrest, thereby necessitating further large-scale studies to substantiate whether these correlations differ according to gender and the location of cardiac arrest.


Assuntos
Circulação Sanguínea/fisiologia , Parada Cardíaca/fisiopatologia , Oximetria/métodos , Idoso , Idoso de 80 Anos ou mais , Reanimação Cardiopulmonar , Circulação Cerebrovascular/fisiologia , Feminino , Parada Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Parada Cardíaca Extra-Hospitalar/fisiopatologia , Parada Cardíaca Extra-Hospitalar/terapia , Avaliação de Resultados em Cuidados de Saúde , Oxigênio/sangue , Prognóstico , Espectroscopia de Luz Próxima ao Infravermelho/métodos
10.
Ann Surg ; 272(4): 583-588, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32657925

RESUMO

OBJECTIVE: To examine technical-, patient-, tumor-, and treatment-related factors associated with NIR guided SLN identification. BACKGROUND: Missed nodal disease correlates with recurrence in early stage NSCLC. NIR-guided SLN mapping may improve staging and outcomes through identification of occult nodal disease. METHODS: Retrospective analysis of 2 phase I clinical trials investigating NIR-guided SLN mapping utilizing ICG in patients with surgically resectable NSCLC. RESULTS: In total, 66 patients underwent NIR-guided SLN mapping and lymphadenectomy after peritumoral ICG injection. There was significantly increased likelihood of SLN identification with injection dose ≥1 mg compared to <1 mg (65.2% vs 35.0%, P = 0.05), lung ventilation after injection (65.2% vs 35.0%, P = 0.05), and albumin dissolvent (68.1%) compared to fresh frozen plasma (28.6%) and sterile water (20.0%) (P = 0.01). In patients receiving the optimized ICG injection, there was significantly increased likelihood of SLN identification with radiologically solid nodules compared to sub-solid nodules (77.4% vs 33.3%, P = 0.04) and anatomic resection compared to wedge resection (88.2% vs 52.2%, P = 0.04). Disease-free and overall survival are 100% in those with a histologically negative SLN identified (n = 25) compared to 73.6% (P = 0.02) and 63.6% (P = 0.01) in patients with node negative NSCLC established via routine lymphadenectomy alone (n = 22). CONCLUSIONS: SLN(s) are more reliably identified with ICG dose ≥1 mg, albumin dissolvent, post-injection lung ventilation, radiologically solid nodules, and anatomic resections. To date, N0 status when established via NIR SLN mapping seems to be associated with decreased recurrence and improved survival after surgery for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/secundário , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Linfonodo Sentinela/diagnóstico por imagem , Linfonodo Sentinela/patologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Corantes , Humanos , Verde de Indocianina , Estudos Retrospectivos
11.
Food Chem ; 333: 127449, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659663

RESUMO

The demand for the development of fast, easy-to-use and low-cost analytical methods for food adulteration analysis has being increasing in the last years. Although infrared spectroscopic techniques offer these advantages, the validation of screening methods requiring the application of multivariate data treatment is less frequently described in literature thus limiting their use as routine tools in control laboratories for food fraud monitoring. In this paper, an EU-validation procedure for screening methods was successfully applied to a multivariate FT-NIR spectroscopic method for the screening of durum wheat pasta samples adulterated with common wheat at the screening target concentration of 3%. Good results in terms of the cut-off value (2.32% mass fraction of soft wheat) and false suspect rates (0.1% for blanks; 13% at 1% mass fraction) demonstrated that the present validation approach would be a proof-of-strategy to be used for multivariate infrared methods applied for screening purposes.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Triticum/química , Farinha/análise , Análise de Alimentos/estatística & dados numéricos , Análise dos Mínimos Quadrados , Análise Multivariada , Espectroscopia de Luz Próxima ao Infravermelho/estatística & dados numéricos
12.
J Food Sci ; 85(7): 2020-2031, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32602154

RESUMO

Near infrared spectroscopy in combination with a transflection probe was investigated as inline measurement in a continuous flash pasteurizer system with a sugar-water model solution. Robustness and reproducibility of fluctuations of recorded spectra as well as trueness of the chemometric analysis were compared under different process parameter settings. Variable parameters were the flow rate (from laminar flow at 30 L/h to turbulent flow at 90 L/h), temperature (20 to 100 °C) and the path length of the transflection probe (2 and 4 mm) while the pressure was kept constant at 2.5 bar. Temperature and path length were identified as the most affecting parameters, in case of homogenous test medium. In case of particle containing systems, the flow rate could have an impact as well. However, the application of a PLS model, which includes a broad temperature range, and the correction of prediction results by applying a polynomial regression function for prediction errors, was able to compensate these effects. Also, a path length of 2 mm leads to a higher accuracy. The applied strategy shows that by the identification of relevant process parameters and settings as well as the establishment of a compensation strategy, near infrared spectroscopy is a powerful process analytical tool for continuous flash pasteurization systems.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho/métodos , Açúcares/química , Água/química , Análise dos Mínimos Quadrados , Pasteurização , Temperatura
13.
Food Chem ; 332: 127419, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32622190

RESUMO

Aflatoxins (AFs) are potent carcinogens present in numerous crops. Access to accurate methods for evaluating contamination is a critical factor in aflatoxin risk assessment. Versicolorin A (Ver A), a precursor of aflatoxin B1 (AFB1), can be used as an indicator for the presence of AFB1, even when the AF is not yet detectable. Currently employed Ver A detection methods are expensive, time consuming, and difficult to apply to numerous samples. Herein, Ver A was detected via near-infrared spectroscopy. Both quantitative and two-grade sorting methods were set-up using the extreme gradient boosting algorithm coupled with a support vector machine. This two-tiered method obtained a root-mean-square error of prediction value of 3.57 µg/kg for the quantitative model, and an accuracy rate of 90.32% for the sorting approach. This novel method is rapid, accurate, solvent free, requires no sample pretreatment, and detects Ver A in maize, making it convenient for practical use.


Assuntos
Aflatoxina B1/análise , Antraquinonas/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Zea mays/química , Contaminação de Alimentos/análise , Humanos
14.
Surg Clin North Am ; 100(4): 807-822, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32681878

RESUMO

Peripheral arterial disease (PAD) affects many individuals worldwide and is associated with increased morbidity and mortality. Controversy exists on whether or not to screen asymptomatic patients. Further complicating this is that many patients with a chronic lower extremity wound are often asymptomatic. PAD and traditional noninvasive vascular studies may be inaccurate in providing a correct diagnosis. A review of current and novel vascular assessment modalities along with their benefits and limitations are presented here. A combination of these vascular assessments may help improve accuracy in diagnosis, providing timely care to those patients in need.


Assuntos
Perna (Membro)/irrigação sanguínea , Doença Arterial Periférica/fisiopatologia , Índice Tornozelo-Braço , Monitorização Transcutânea dos Gases Sanguíneos/métodos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Humanos , Pele/irrigação sanguínea , Dermatopatias Vasculares/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Sístole/fisiologia , Cicatrização/fisiologia
15.
Anticancer Res ; 40(7): 3873-3882, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32620627

RESUMO

BACKGROUND/AIM: This study investigated the use of near-infrared fluorescent imaging for securing safe margins during liver resection. PATIENTS AND METHODS: This study included 125 patients who underwent liver tumor resection in 2014-2018. Indocyanine green testing was performed 2-14 days before surgery. Histopathological specimens of hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM) were evaluated using fluorescent microscopy. RESULTS: Fluorescence microscopy identified signals in 26/53 (49.0%) and 36/72 (50%) cases of HCC and CRLM, respectively. HCC demonstrated total, partial, rim, and combined fluorescence patterns; CRLM uniformly demonstrated rim fluorescence. Although rim fluorescence was seen in both HCC and CRLM, no malignancy was confirmed pathologically in the peritumoral area demonstrating fluorescence. The median widths of fluorescence from the tumor edge in HCC and CRLM were 1227.5 µm and 1608 µm, respectively, with no significant difference. CONCLUSION: Near-infrared fluorescent imaging can reliably detect safe surgical margins intraoperatively during liver resection.


Assuntos
Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico por imagem , Feminino , Hepatectomia/métodos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Margens de Excisão , Microscopia de Fluorescência , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Espectroscopia de Luz Próxima ao Infravermelho/métodos
16.
J Vis Exp ; (159)2020 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-32510492

RESUMO

Concurrent EEG and fNIRS recordings offer an excellent opportunity to gain a full understanding of the neural mechanism of cognitive processing by inspecting the relationship between the neural and hemodynamic signals. EEG is an electrophysiological technology that can measure the rapid neuronal activity of the cortex, whereas fNIRS relies on the hemodynamic responses to infer brain activation. The combination of EEG and fNIRS neuroimaging techniques can identify more features and reveal more information associated with the functioning of the brain. In this protocol, fused EEG-fNIRS measurements were performed for concurrent recordings of evoked-electrical potentials and hemodynamic responses during a Flanker task. In addition, the critical steps for setting up the hardware and software system as well as the procedures for data acquisition and analysis were provided and discussed in detail. It is expected that the present protocol can pave a new avenue for improving the understanding of the neural mechanisms underlying various cognitive processes by using the EEG and fNIRS signals.


Assuntos
Encéfalo/fisiologia , Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados , Hemodinâmica , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Humanos
17.
J Food Sci ; 85(7): 2004-2009, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32529767

RESUMO

Pseudostellaria heterophylla is a very popular traditional Chinese medicine herb, also called "Taizishen." Discrimination of P. heterophylla from different regions is critical for ensuring the effectiveness of drug use, because the drug effects of P. heterophylla from different regions are diversity of each other. To discriminate P. heterophylla from different regions rapidly and effectively, a model extracted by competitive adaptive reweighted sampling (CARS) was established. Original spectra of P. heterophylla in wave number range of 10,000 to 4,000 cm-1 were acquired. Orthogonal partial least squares discriminant analysis (OPLS-DA) was also used to establish a suitable model. CARS was performed for extracting key wave number variables. We found that the near-infrared spectrum of a series of samples analyzed by Row-center-SG, CARS, and OPLS-DA can effectively distinguish the P. heterophylla from different regions, and the accuracy of OPLS-DA model is also satisfactory in terms of good discrimination rate. These results show that the Row-center-SG, CARS, and OPLS-DA model can be used to identify the P. heterophylla from different regions. PRACTICAL APPLICATION: According to our research results, we can draw a conclusion that our research results may be used to distinguish the traditional Chinese medicine from those from different places of origin and the powder with similar appearance.


Assuntos
Caryophyllales/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , China , Análise Discriminante , Análise dos Mínimos Quadrados , Pós/química
18.
Food Chem ; 331: 127359, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32580128

RESUMO

Cyanide is a highly toxic anion. Nonetheless, many food plants could produce endogenous cyanide, which causes great danger to human health. Thus, monitoring cyanide in food samples is critically significant. Herein, we rationally developed the first ratiometric near-infrared fluorescent probe for sensing cyanide in food samples. The probe displayed noticeable fluorescence in near-infrared region. Moreover, upon treatment with cyanide, the probe exhibited highly selective and sensitive ratiometric fluorescence response, with limit of detection determined to be 0.075 µM and limit of quantification determined to be 0.25 µM. The ratios of fluorescent intensities at 519 and 688 nm (I519/I688) was linear with added cyanide concentrations from 0 to 80 µM. The relative standard deviations for repeatability and reproducibility varied from 0.55 to 8.94 and from 1.17 to 9.46, respectively. Significantly, probe Hy has been successfully applied for monitoring cyanide in various food samples, such as almonds, sprouting potatoes, and bamboo shoots.


Assuntos
Cianetos/análise , Corantes Fluorescentes/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Limite de Detecção , Prunus dulcis/química , Reprodutibilidade dos Testes , Sasa/química , Sensibilidade e Especificidade , Solanum tuberosum/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos
19.
PLoS One ; 15(6): e0234557, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555660

RESUMO

After mating, female mosquitoes need animal blood to develop their eggs. In the process of acquiring blood, they may acquire pathogens, which may cause different diseases in humans such as malaria, zika, dengue, and chikungunya. Therefore, knowing the parity status of mosquitoes is useful in control and evaluation of infectious diseases transmitted by mosquitoes, where parous mosquitoes are assumed to be potentially infectious. Ovary dissections, which are currently used to determine the parity status of mosquitoes, are very tedious and limited to few experts. An alternative to ovary dissections is near-infrared spectroscopy (NIRS), which can estimate the age in days and the infectious state of laboratory and semi-field reared mosquitoes with accuracies between 80 and 99%. No study has tested the accuracy of NIRS for estimating the parity status of wild mosquitoes. In this study, we train an artificial neural network (ANN) models on NIR spectra to estimate the parity status of wild mosquitoes. We use four different datasets: An. arabiensis collected from Minepa, Tanzania (Minepa-ARA); An. gambiae s.s collected from Muleba, Tanzania (Muleba-GA); An. gambiae s.s collected from Burkina Faso (Burkina-GA); and An.gambiae s.s from Muleba and Burkina Faso combined (Muleba-Burkina-GA). We train ANN models on datasets with spectra preprocessed according to previous protocols. We then use autoencoders to reduce the spectra feature dimensions from 1851 to 10 and re-train the ANN models. Before the autoencoder was applied, ANN models estimated parity status of mosquitoes in Minepa-ARA, Muleba-GA, Burkina-GA and Muleba-Burkina-GA with out-of-sample accuracies of 81.9±2.8 (N = 274), 68.7±4.8 (N = 43), 80.3±2.0 (N = 48), and 75.7±2.5 (N = 91), respectively. With the autoencoder, ANN models tested on out-of-sample data achieved 97.1±2.2% (N = 274), 89.8 ± 1.7% (N = 43), 93.3±1.2% (N = 48), and 92.7±1.8% (N = 91) accuracies for Minepa-ARA, Muleba-GA, Burkina-GA, and Muleba-Burkina-GA, respectively. These results show that a combination of an autoencoder and an ANN trained on NIR spectra to estimate the parity status of wild mosquitoes yields models that can be used as an alternative tool to estimate parity status of wild mosquitoes, especially since NIRS is a high-throughput, reagent-free, and simple-to-use technique compared to ovary dissections.


Assuntos
Anopheles/fisiologia , Malária/transmissão , Mosquitos Vetores/fisiologia , Redes Neurais de Computação , Oviparidade , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Animais , Feminino , Humanos
20.
Parasit Vectors ; 13(1): 160, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228670

RESUMO

BACKGROUND: Practical, field-ready age-grading tools for mosquito vectors of disease are urgently needed because of the impact that daily survival has on vectorial capacity. Previous studies have shown that near-infrared spectroscopy (NIRS), in combination with chemometrics and predictive modeling, can forecast the age of laboratory-reared mosquitoes with moderate to high accuracy. It remains unclear whether the technique has utility for identifying shifts in the age structure of wild-caught mosquitoes. Here we investigate whether models derived from the laboratory strain of mosquitoes can be used to predict the age of mosquitoes grown from pupae collected in the field. METHODS: NIRS data from adult female Aedes albopictus mosquitoes reared in the laboratory (2, 5, 8, 12 and 15 days-old) were analysed against spectra from mosquitoes emerging from wild-caught pupae (1, 7 and 14 days-old). Different partial least squares (PLS) regression methods trained on spectra from laboratory mosquitoes were evaluated on their ability to predict the age of mosquitoes from more natural environments. RESULTS: Models trained on spectra from laboratory-reared material were able to predict the age of other laboratory-reared mosquitoes with moderate accuracy and successfully differentiated all day 2 and 15 mosquitoes. Models derived with laboratory mosquitoes could not differentiate between field-derived age groups, with age predictions relatively indistinguishable for day 1-14. Pre-processing of spectral data and improving the PLS regression framework to avoid overfitting can increase accuracy, but predictions of mosquitoes reared in different environments remained poor. Principal components analysis confirms substantial spectral variations between laboratory and field-derived mosquitoes despite both originating from the same island population. CONCLUSIONS: Models trained on laboratory mosquitoes were able to predict ages of laboratory mosquitoes with good sensitivity and specificity though they were unable to predict age of field-derived mosquitoes. This study suggests that laboratory-reared mosquitoes do not capture enough environmental variation to accurately predict the age of the same species reared under different conditions. Further research is needed to explore alternative pre-processing methods and machine learning techniques, and to understand factors that affect absorbance in mosquitoes before field application using NIRS.


Assuntos
Culicidae/química , Culicidae/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Aedes/química , Aedes/fisiologia , Animais , Vetores de Doenças , Entomologia/métodos , Feminino , Aprendizado de Máquina , Mosquitos Vetores/química , Mosquitos Vetores/fisiologia , Especificidade da Espécie
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