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1.
Appl Spectrosc ; 76(3): 273-283, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35102755

RESUMO

Hematuria refers to the presence of blood in urine. Even in small amounts, it may be indicative of disease, ranging from urinary tract infection to cancer. Here, Raman spectroscopy was used to detect and quantify macro- and microhematuria in human urine samples. Anticoagulated whole blood was mixed with freshly collected urine to achieve concentrations of 0, 0.25, 0.5, 1, 2, 6, 10, and 20% blood/urine (v/v). Raman spectra were obtained at 785 nm and data analyzed using chemometric methods and statistical tests with the Rametrix toolboxes for Matlab. Goldindec and iterative smoothing splines with root error adjustment (ISREA) baselining algorithms were used in processing and normalization of Raman spectra. Rametrix was used to apply principal component analysis (PCA), develop discriminate analysis of principal component (DAPC) models, and to validate these models using external leave-one-out cross-validation (LOOCV). Discriminate analysis of principal component models were capable of detecting various levels of microhematuria in unknown urine samples, with prediction accuracies of 91% (using Goldindec spectral baselining) and 94% (using ISREA baselining). Partial least squares regression (PLSR) was then used to estimate/quantify the amount of blood (v/v) in a urine sample, based on its Raman spectrum. Comparing actual and predicted (from Raman spectral computations) hematuria levels, a coefficient of determination (R2) of 0.91 was obtained over all hematuria levels (0-20% v/v), and an R2 of 0.92 was obtained for microhematuria (0-1% v/v) specifically. Overall, the results of this preliminary study suggest that Raman spectroscopy and chemometric analyses can be used to detect and quantify macro- and microhematuria in unprocessed, clinically relevant urine specimens.


Assuntos
Hematúria , Análise Espectral Raman , Hematúria/diagnóstico , Humanos , Análise dos Mínimos Quadrados , Análise de Componente Principal , Análise Espectral Raman/métodos
2.
PLoS One ; 15(8): e0237070, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822394

RESUMO

Bladder cancer (BCA) is relatively common and potentially recurrent/progressive disease. It is also costly to detect, treat, and control. Definitive diagnosis is made by examination of urine sediment, imaging, direct visualization (cystoscopy), and invasive biopsy of suspect bladder lesions. There are currently no widely-used BCA-specific biomarker urine screening tests for early BCA or for following patients during/after therapy. Urine metabolomic screening for biomarkers is costly and generally unavailable for clinical use. In response, we developed Raman spectroscopy-based chemometric urinalysis (Rametrix™) as a direct liquid urine screening method for detecting complex molecular signatures in urine associated with BCA and other genitourinary tract pathologies. In particular, the RametrixTM screen used principal components (PCs) of urine Raman spectra to build discriminant analysis models that indicate the presence/absence of disease. The number of PCs included was varied, and all models were cross-validated by leave-one-out analysis. In Study 1 reported here, we tested the Rametrix™ screen using urine specimens from 56 consented patients from a urology clinic. This proof-of-concept study contained 17 urine specimens with active BCA (BCA-positive), 32 urine specimens from patients with other genitourinary tract pathologies, seven specimens from healthy patients, and the urinalysis control SurineTM. Using a model built with 22 PCs, BCA was detected with 80.4% accuracy, 82.4% sensitivity, 79.5% specificity, 63.6% positive predictive value (PPV), and 91.2% negative predictive value (NPV). Based on the number of PCs included, we found the RametrixTM screen could be fine-tuned for either high sensitivity or specificity. In other studies reported here, RametrixTM was also able to differentiate between urine specimens from patients with BCA and other genitourinary pathologies and those obtained from patients with end-stage kidney disease (ESKD). While larger studies are needed to improve RametrixTM models and demonstrate clinical relevance, this study demonstrates the ability of the RametrixTM screen to differentiate urine of BCA-positive patients. Molecular signature variances in the urine metabolome of BCA patients included changes in: phosphatidylinositol, nucleic acids, protein (particularly collagen), aromatic amino acids, and carotenoids.


Assuntos
Detecção Precoce de Câncer/métodos , Análise Espectral Raman/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Adulto , Idoso , Biomarcadores Tumorais/urina , Cistoscopia , Análise Discriminante , Feminino , Humanos , Masculino , Metaboloma , Metabolômica , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Urinálise/métodos , Neoplasias da Bexiga Urinária/patologia
3.
PLoS One ; 15(1): e0227281, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923235

RESUMO

Raman Chemometric Urinalysis (RametrixTM) was used to discern differences in Raman spectra from (i) 362 urine specimens from patients receiving peritoneal dialysis (PD) therapy for end-stage kidney disease (ESKD), (ii) 395 spent dialysate specimens from those PD therapies, and (iii) 235 urine specimens from healthy human volunteers. RametrixTM analysis includes spectral processing (e.g., truncation, baselining, and vector normalization); principal component analysis (PCA); statistical analyses (ANOVA and pairwise comparisons); discriminant analysis of principal components (DAPC); and testing DAPC models using a leave-one-out build/test validation procedure. Results showed distinct and statistically significant differences between the three types of specimens mentioned above. Further, when introducing "unknown" specimens, RametrixTM was able to identify the type of specimen (as PD patient urine or spent dialysate) with better than 98% accuracy, sensitivity, and specificity. RametrixTM was able to identify "unknown" urine specimens as from PD patients or healthy human volunteers with better than 96% accuracy (with better than 97% sensitivity and 94% specificity). This demonstrates that an entire Raman spectrum of a urine or spent dialysate specimen can be used to determine its identity or the presence of ESKD by the donor.


Assuntos
Falência Renal Crônica/urina , Análise Espectral Raman/métodos , Urinálise/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Confiabilidade dos Dados , Soluções para Diálise , Feminino , Voluntários Saudáveis , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal , Análise de Componente Principal , Sensibilidade e Especificidade , Adulto Jovem
4.
Int J Pharm ; 574: 118869, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31765787

RESUMO

Melting points for new drugs are reported in regulatory documents, e.g. investigational brochures, and frequently in published research; however, the authors do not typically consider that heat-induced degradation can affect the melting point measurement. Applying a single heating rate is not adequate, and thus many melting points in the literature and regulatory documentation are not valid. Our aim was to validate a five-stage approach for the melting point measurement of heat-sensitive drugs. These stages are; (1) observe melting; (2) record mass loss; (3) measure melting points at different heating rates; (4) characterise degradation and (5) test for potential isomerisation. Applying this approach to pilocarpine HCl illustrated the sensitivity of a melting point to thermal degradation. Due to salt disproportionation & loss of HCl gas, pilocarpine's melting point decreased by 14 °C when the heating rate was lowered from 20 to 1 °C/min. Epimerization occurred before melting was reached. Increasing the heating rate diminished disproportionation; however, this did not remove epimerization. Thus, the melting point of pilocarpine HCl of 205.5 ± 0.4 °C measured at 20 °C/min represents the melt of a racemic mixture containing inactive isopilocarpine. Heating above the melting point accelerated degradation, a rate of 5 °C/min recovered just 38 ± 1% of pilocarpine. Such data predicted a shelf-life of 6.6 years. Pilocarpine successfully validated the multistage approach by providing new knowledge concerning its thermal stability. Our 5-stage approach must be applied to all new drugs especially if their formulation requires heat. For example, thermal stability is an infrequently considered pre-requisite in the emerging field of 3D printing.


Assuntos
Pilocarpina/química , Calefação/métodos , Temperatura Alta , Termodinâmica , Temperatura de Transição
5.
PLoS One ; 14(9): e0222115, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31560690

RESUMO

Raman chemometric urinalysis (Rametrix™) was used to analyze 235 urine specimens from healthy individuals. The purpose of this study was to establish the "range of normal" for Raman spectra of urine specimens from healthy individuals. Ultimately, spectra falling outside of this range will be correlated with kidney and urinary tract disease. Rametrix™ analysis includes direct comparisons of Raman spectra but also principal component analysis (PCA), discriminant analysis of principal components (DAPC) models, multivariate statistics, and it is available through GitHub as the Rametrix™ LITE Toolbox for MATLAB®. Results showed consistently overlapping Raman spectra of urine specimens with significantly larger variances in Raman shifts, found by PCA, corresponding to urea, creatinine, and glucose concentrations. A 2-way ANOVA test found that age of the urine specimen donor was statistically significant (p < 0.001) and donor sex (female or male identification) was less so (p = 0.0526). With DAPC models and blind leave-one-out build/test routines using the Rametrix™ PRO Toolbox (also available through GitHub), an accuracy of 71% (sensitivity = 72%; specificity = 70%) was obtained when predicting whether a urine specimen from a healthy unknown individual was from a female or male donor. Finally, from female and male donors (n = 4) who contributed first morning void urine specimens each day for 30 days, the co-occurrence of menstruation was found statistically insignificant to Rametrix™ results (p = 0.695). In addition, Rametrix™ PRO was able to link urine specimens with the individual donor with an average of 78% accuracy. Taken together, this study established the range of Raman spectra that could be expected when obtaining urine specimens from healthy individuals and analyzed by Rametrix™ and provides the methodology for linking results with donor characteristics.


Assuntos
Urinálise/métodos , Urina/química , Adolescente , Adulto , Idoso , Creatinina/urina , Análise Discriminante , Feminino , Glicosúria/urina , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Componente Principal , Valores de Referência , Análise Espectral Raman/métodos , Ureia/urina , Urinálise/estatística & dados numéricos , Adulto Jovem
6.
J Ind Microbiol Biotechnol ; 43(10): 1355-63, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27423881

RESUMO

An evolutionary engineering approach for enhancing heterologous carotenoids production in an engineered Saccharomyces cerevisiae strain was used previously to isolate several carotenoids hyper-producers from the evolved populations. ß-Carotene production was characterized in the parental and one of the evolved carotenoids hyper-producers (SM14) using bench-top bioreactors to assess the impact of pH, aeration, and media composition on ß-carotene production levels. The results show that with maintaining a low pH and increasing the carbon-to-nitrogen ratio (C:N) from 8.8 to 50 in standard YNB medium, a higher ß-carotene production level at 25.52 ± 2.15 mg ß-carotene g(-1) (dry cell weight) in the carotenoids hyper-producer was obtained. The increase in C:N ratio also significantly increased carotenoids production in the parental strain by 298 % [from 5.68 ± 1.24 to 22.58 ± 0.11 mg ß-carotene g(-1) (dcw)]. In this study, it was shown that Raman spectroscopy is capable of monitoring ß-carotene production in these cultures. Raman spectroscopy is adaptable to large-scale fermentations and can give results in near real-time. Furthermore, we found that Raman spectroscopy was also able to measure the relative lipid compositions and protein content of the parental and SM14 strains at two different C:N ratios in the bioreactor. The Raman analysis showed a higher total fatty acid content in the SM14 compared with the parental strain and that an increased C:N ratio resulted in significant increase in total fatty acid content of both strains. The data suggest a positive correlation between the yield of ß-carotene per biomass and total fatty acid content of the cell.


Assuntos
Reatores Biológicos , Saccharomyces cerevisiae/metabolismo , Análise Espectral Raman , beta Caroteno/biossíntese , Biomassa , Fermentação , Nitrogênio/metabolismo
7.
Int J Environ Res Public Health ; 10(12): 6764-82, 2013 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-24304507

RESUMO

Strategies to support people living with dementia are broad in scope, proposing both pharmacological and non-pharmacological interventions as part of the care pathway. Assistive technologies form part of this offering as both stand-alone devices to support particular tasks and the more complex offering of the "smart home" to underpin ambient assisted living. This paper presents a technology-based system, which expands on the smart home architecture, orientated to support people with daily living. The system, NOCTURNAL, was developed by working directly with people who had dementia, and their carers using qualitative research methods. The research focused primarily on the nighttime needs of people living with dementia in real home settings. Eight people with dementia had the final prototype system installed for a three month evaluation at home. Disturbed sleep patterns, night-time wandering were a focus of this research not only in terms of detection by commercially available technology but also exploring if automated music, light and visual personalized photographs would be soothing to participants during the hours of darkness. The NOCTURNAL platform and associated services was informed by strong user engagement of people with dementia and the service providers who care for them. NOCTURNAL emerged as a holistic service offering a personalised therapeutic aspect with interactive capabilities.


Assuntos
Demência/terapia , Serviços de Saúde para Idosos , Serviços de Assistência Domiciliar , Transtornos do Sono-Vigília/terapia , Telemedicina/métodos , Pesquisa Participativa Baseada na Comunidade , Demência/complicações , Humanos , Vida Independente , Gestão de Riscos , Transtornos do Sono-Vigília/complicações
8.
Nanotechnology ; 24(27): 275102, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23780336

RESUMO

A new image analysis method called the spatial phantom evaluation of cellular thermal response in layers (SPECTRL) is presented for assessing spatial viability response to nanoparticle enhanced photothermal therapy in tissue representative phantoms. Sodium alginate phantoms seeded with MDA-MB-231 breast cancer cells and single-walled nanohorns were laser irradiated with an ytterbium fiber laser at a wavelength of 1064 nm and irradiance of 3.8 W cm(-2) for 10-80 s. SPECTRL quantitatively assessed and correlated 3D viability with spatiotemporal temperature. Based on this analysis, kill and transition zones increased from 3.7 mm(3) and 13 mm(3) respectively to 44.5 mm(3) and 44.3 mm(3) as duration was increased from 10 to 80 s. SPECTRL provides a quantitative tool for measuring precise spatial treatment regions, providing information necessary to tailor therapy protocols.


Assuntos
Carbono/uso terapêutico , Nanoestruturas/uso terapêutico , Neoplasias/diagnóstico , Neoplasias/terapia , Alginatos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular , Diagnóstico por Imagem/métodos , Ácido Glucurônico/uso terapêutico , Ácidos Hexurônicos/uso terapêutico , Humanos , Terapia com Luz de Baixa Intensidade/métodos , Imagens de Fantasmas , Temperatura
9.
Int J Hyperthermia ; 29(4): 281-95, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23738696

RESUMO

PURPOSE: Predictions of injury in response to photothermal therapy in vivo are frequently made using Arrhenius parameters obtained from cell monolayers exposed to laser or water bath heating. However, the impact of different heating methods and cellular microenvironments on Arrhenius predictions has not been thoroughly investigated. This study determined the influence of heating method (water bath and laser irradiation) and cellular microenvironment (cell monolayers and tissue phantoms) on Arrhenius parameters and spatial viability. METHODS: MDA-MB-231 cells seeded in monolayers and sodium alginate phantoms were heated with a water bath for 3-20 min at 46, 50, and 54 °C or laser irradiated (wavelength of 1064 nm and fluences of 40 W/cm(2) or 3.8 W/cm(2) for 0-4 min) in combination with photoabsorptive carbon nanohorns. Spatial viability was measured using digital image analysis of cells stained with calcein AM and propidium iodide and used to determine Arrhenius parameters. The influence of microenvironment and heating method on Arrhenius parameters and capability of parameters derived from more simplistic experimental conditions (e.g. water bath heating of monolayers) to predict more physiologically relevant systems (e.g. laser heating of phantoms) were assessed. RESULTS: Arrhenius predictions of the treated area (<1% viable) under-predicted the measured areas in photothermally treated phantoms by 23 mm(2) using water bath treated cell monolayer parameters, 26 mm(2) using water bath treated phantom parameters, 27 mm(2) using photothermally treated monolayer parameters, and 0.7 mm(2) using photothermally treated phantom parameters. CONCLUSIONS: Heating method and cellular microenvironment influenced Arrhenius parameters, with heating method having the greater impact.


Assuntos
Hipertermia Induzida/métodos , Modelos Biológicos , Linhagem Celular Tumoral , Sobrevivência Celular , Microambiente Celular , Temperatura Alta , Humanos , Hipertermia Induzida/efeitos adversos , Lasers , Software , Água
10.
Lasers Med Sci ; 28(4): 1143-50, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23053245

RESUMO

Laser-based photothermal therapies for urothelial cell carcinoma (UCC) are limited to thermal ablation of superficial tumors, as treatment of invasive lesions is hampered by shallow light penetration in bladder tissue at commonly used therapeutic wavelengths. This study evaluates the utilization of sharp, silica, fiberoptic microneedle devices (FMDs) to deliver single-walled carbon nanohorns (SWNHs) serving as exogenous chromophores in conjunction with a 1,064-nm laser to amplify thermal treatment doses in a spatially controlled manner. Experiments were conducted to determine the lateral and depth dispersal of SWNHs in aqueous solution (0.05 mg/mL) infused through FMDs into the wall of healthy, inflated, ex vivo porcine bladders. SWNH-perfused bladder regions were irradiated with a free-space, CW, 1,064-nm laser in order to determine the SWNH efficacy as exogenous chromophores within the organ. SWNHs infused at a rate of 50 µL/min resulted in an average lateral expansion rate of 0.36 ± 0.08 cm(2)/min. Infused SWNHs dispersal depth was limited to the urothelium and muscular propria for 50 µL/min infusions of 10 min or less, but dispersed through the entire thickness after a 15-min infusion period. Irradiation of SWNH-perfused bladder tissue with 1,064 nm laser light at 0.95 W/cm(2) over 40 s exhibited a maximum increase of approximately 19 °C compared with an increase of approximately 3 °C in a non-perfused control. The results indicate that these silica FMDs can successfully penetrate into the bladder wall to rapidly distribute SWNHs with some degree of lateral and depth control and that SWNHs may be a viable exogenous chromophore for photothermal amplification of laser-based UCC treatments.


Assuntos
Hipertermia Induzida/instrumentação , Nanotubos de Carbono , Fibras Ópticas , Bexiga Urinária/efeitos da radiação , Bexiga Urinária/cirurgia , Animais , Carcinoma de Células de Transição/terapia , Desenho de Equipamento , Feminino , Humanos , Lasers de Estado Sólido/uso terapêutico , Masculino , Nanotubos de Carbono/efeitos da radiação , Sus scrofa , Neoplasias da Bexiga Urinária/terapia
11.
Nanomedicine (Lond) ; 7(11): 1729-42, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22812710

RESUMO

AIM: Nanoparticle-enhanced photothermal therapy is a promising alternative to tumor resection. However, quantitative measurements of cellular response to these treatments are limited. This article introduces a Bimodal Enhanced Analysis of Spatiotemporal Temperature (BEAST) algorithm to rapidly determine the viability of cancer cells in vitro following photothermal therapy alone or in combination with nanoparticles. MATERIALS & METHODS: To illustrate the capability of the BEAST viability algorithm, single wall carbon nanohorns were added to renal cancer (RENCA) cells in vitro and time-dependent spatial temperature maps measured with an infrared camera during laser therapy were correlated with post-treatment cell viability distribution maps obtained by cell-staining fluorescent microscopy. CONCLUSION: The BEAST viability algorithm accurately and rapidly determined the cell viability as a function of time, space and temperature.


Assuntos
Processamento de Imagem Assistida por Computador , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Rim/patologia , Terapia a Laser , Nanopartículas/uso terapêutico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Processamento de Imagem Assistida por Computador/métodos , Rim/citologia , Camundongos , Microscopia de Fluorescência , Temperatura
12.
Ann N Y Acad Sci ; 974: 565-80, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12446348

RESUMO

Thin films of an organic nonlinear optical (NLO) material, N, N-dimethyl-p-(2,2-dicyanovinyl) aniline (DCVA), have been grown in space and on the ground by physical vapor transport in an effusive ampoule arrangement. The thin film growth technique developed on the ground is a direct result of information gleaned from experiments in microgravity. This paper covers the results of our experimental investigations for establishing "ideal" terrestrial conditions for deposition of a DCVA film. The active control during the deposition process was exercised by three deposition variables: the material source temperature, the background pressure external to the growth ampoule and the substrate temperature. Successful growth occurred when the difference in temperature between the source material and the copper substrate was 14 degrees C and the background nitrogen pressure was such that the transport was either diffusive or convective. A qualitative diffusion limited boundary was estimated to occur at a pressure of approximately 20 torr. We have probed the DCVA thin films with visible-near infrared reflection absorption spectroscopy, polarized Fourier transform infrared spectrometry, differential interference contrast optical microscopy, and stylus profilometry.


Assuntos
Compostos de Anilina/química , Pressão , Voo Espacial , Temperatura , Ausência de Peso , Convecção , Cobre , Cristalização , Difusão , Vidro , Microscopia de Interferência , Nitrogênio , Óptica e Fotônica , Espectroscopia de Infravermelho com Transformada de Fourier , Volatilização
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