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1.
Am J Obstet Gynecol ; 226(1): 100.e1-100.e6, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34487702

RESUMO

BACKGROUND: Intraoperative evaluation of ureteral patency is often performed in gynecologic and urogynecologic surgery. Many agents are used to help assess the patency, each with its own associated cost, ease of use, and adverse reactions. Some agents, such as dextrose, are used as an instillation fluid to create a viscosity difference and aid the visualization of a ureteral jet. Others, such as oral phenazopyridine or the intravenous use of sodium fluorescein and indigo carmine, cause a color change of the urine to directly aid the visualization of ureteral jets. Recently, numerous studies have examined the efficacy and surgeon satisfaction of these agents. The studies have also emphasized certain options as associated with a lower cost. However, there have not been any cost studies comparing these agents. OBJECTIVE: To compare the cost-effectiveness of the following 4 agents that are commonly used in assessing ureteral patency intraoperatively: oral phenazopyridine, dextrose instillation, intravenous sodium fluorescein, and intravenous indigo carmine. STUDY DESIGN: We constructed a decision-analytic model to compare cystoscopy using oral phenazopyridine, dextrose instillation, intravenous sodium fluorescein, and intravenous indigo carmine. Failure to see efflux resulted in work-ups for ureteral obstruction. The probabilities were obtained from published studies, and the probability of successfully seeing efflux ranged from 0.92 with oral phenazopyridine to 0.99 with intravenous indigo carmine. The costs of the agents, adverse effects, and ureteral obstruction work-ups were obtained from the University of North Carolina at Chapel Hill Department of Pharmacy, the Healthcare Cost and Utilization Project 2016 database and the FAIR Health Consumer database. The cost of a ureteral obstruction work-up used in our model ranged from $9755 for intraoperative evaluation with retrograde pyelograms and stents to $29,034 for hospitalization. Our primary outcome was the incremental cost-effectiveness ratio per unnecessary work-up for ureteral obstruction avoided. Sensitivity analyses were performed to identify the key uncertainties. RESULTS: Oral phenazopyridine, followed by an intravenous agent if needed, had a mean cost of $110 per patient. Dextrose averaged $151 more per patient, with only a slight improvement in avoiding unnecessary ureteral obstruction work-ups and a higher cost associated with adverse reactions (incremental cost-effectiveness ratio, $62,000). Intravenous agents cost approximately $1000 more per patient and were less effective at preventing unnecessary work-ups. Sensitivity analyses did not identify any thresholds that would significantly change the outcomes. CONCLUSION: Our model suggests that oral phenazopyridine and dextrose instillation are the least expensive and the most effective agents to aid in the visualization of ureteral patency during intraoperative cystoscopy, although dextrose is associated with higher costs owing to a higher rate of adverse reactions (primarily urinary tract infections). Intravenous sodium fluorescein and indigo carmine are historically popular first-choice agents. However, they were found to be more expensive and less effective as primary agents in our model and should likely be reserved for use as secondary agents in the event that the visualization of ureteral jets is unclear with the initial use of phenazopyridine or dextrose.


Assuntos
Corantes/administração & dosagem , Cistoscopia , Procedimentos Cirúrgicos em Ginecologia , Obstrução Ureteral/diagnóstico , Corantes/economia , Análise Custo-Benefício , Feminino , Fluoresceína/administração & dosagem , Fluoresceína/economia , Humanos , Índigo Carmim/administração & dosagem , Índigo Carmim/economia , Complicações Intraoperatórias/diagnóstico , North Carolina , Fenazopiridina/administração & dosagem , Fenazopiridina/economia
2.
Elife ; 102021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34739373

RESUMO

A group leader decided that his lab would share the fluorescent dyes they create, for free and without authorship requirements. Nearly 12,000 aliquots later, he reveals what has happened since.


Assuntos
Corantes/provisão & distribuição , Laboratórios/estatística & dados numéricos , Corantes/economia , Laboratórios/economia , Pessoal de Laboratório/estatística & dados numéricos
3.
Diagn Cytopathol ; 47(5): 469-474, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30585436

RESUMO

OBJECTIVE: Rapid on-site evaluation (ROSE) is a technique beneficial in determining the adequacy of the samples, thereby increasing the diagnostic yield, useful in triage of specimens for ancillary studies and can also help determine a preliminary diagnosis in emergency cases. The different rapid stains for on-site evaluation described in the literature are diff quik, toluidine blue (TB), brilliant cresyl blue (BCB), ultra-fast Pap stains, and rapid hematoxylin and eosin (H&E). This study was undertaken as there is sparse literature regarding the best and the most cost-effective rapid stain. METHOD: Fine needle aspiration samples from 200 patients with palpable swellings in easily accessible regions were taken. Smears stained by rapid and routine stains were assessed based on four parameters, with provisional diagnosis on the rapid stained smears. A comparative analysis of the advantages and disadvantages of the rapid stains was carried out with appropriate statistical tests with the routinely stained smears as gold standard. RESULTS: There was adequate material in 100% of ROSE smears. rapid pap stained smears showed well preserved cytoplasmic details, nuclear details, and background details. The time taken was least with TB and BCB being 5 s each. The most cost-effective was found to be TB. CONCLUSIONS: We conclude that TB is the most cost-effective, quick, least labor-intensive, and reliable rapid stain for ROSE especially in resource-poor settings.


Assuntos
Análise Custo-Benefício , Testes Imediatos/normas , Coloração e Rotulagem/métodos , Biópsia por Agulha Fina/economia , Biópsia por Agulha Fina/métodos , Biópsia por Agulha Fina/normas , Corantes/economia , Corantes/normas , Humanos , Teste de Papanicolaou/economia , Teste de Papanicolaou/normas , Testes Imediatos/economia , Coloração e Rotulagem/economia , Coloração e Rotulagem/normas
4.
Ocul Surf ; 16(1): 139-145, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29107624

RESUMO

PURPOSE: The purpose of this study was to develop a clinically feasible method for obtaining dye concentrations of 2% fluorescein (FL) and 1% lissamine green (LG) by soaking commercially available dye impregnated strips in saline. METHODS: Calibration curves were established to related known concentrations of dye to prepared FL fluorescence and LG absorbance. To determine the optimum number of dye strips and soaking times (preliminary testing), 1, 2, 3 FL or LG strips were soaked in 200 µl commercially available saline for 0.5, 1, 2, 3, 4 and 5 min, using calibration curves to determine FL and LG concentrations. The best combination of number of dye strips and soaking time was soaking 3FL and 3LG strips for 5 min and these were finally tested in 2 ml centrifuge tubes, selected for ease of use in a clinical setting. RESULTS: Preliminary testing indicated that soaking 3 FL or 3 LG strips for 5 min in saline yielded an average (±standard deviation) of 2.0 ± 0.000% FL and 0.93 ± 0.010% LG. Final testing of FL in centrifuge tubes (strips soaked for 3-15 min) yielded an average of 1.99 ± 0.040% FL, with no significant difference among time periods or dye lots tested. However, LG showed more variable results with an average of 0.80 ± 0.160% LG (5-15 min), with significant differences among dye lots and times (2-way ANOVA, p < 0.05). CONCLUSIONS: This simple, reliable and relatively inexpensive method involves soaking 3 FL or LG strips in saline solution, yielding concentrations close to the 2%FL and 1%LG recommended for clinical trials, although LG showed more variability.


Assuntos
Corantes/análise , Fluoresceína/análise , Corantes Fluorescentes/análise , Corantes Verde de Lissamina/análise , Fitas Reagentes/química , Corantes/economia , Análise Custo-Benefício , Técnicas de Diagnóstico Oftalmológico , Composição de Medicamentos , Estudos de Viabilidade , Fluoresceína/economia , Corantes Fluorescentes/economia , Corantes Verde de Lissamina/economia
5.
AMA J Ethics ; 18(8): 793-9, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27550563

RESUMO

The pathologist rarely interacts with patients face-to-face, but he or she nonetheless maintains a crucial relationship with the patient (i.e., the patient-pathologist relationship). A more tangible relationship, the pathologist-clinician relationship, is typically augmented by the patient-pathologist relationship, but at times the two distinct relationships are at odds, creating ethical dilemmas for the pathologist. This case study and discussion highlight some of these potential ethical questions and underscore the need for pathologists and clinicians to have cooperative, collaborative, and professional relationships. Pathologists should feel empowered to guide the clinician's use of appropriate clinical testing to ensure proper management of the patient and responsible use of health care resources.


Assuntos
Corantes , Comportamento Cooperativo , Ética Médica , Relações Interprofissionais , Patologia Clínica/ética , Biópsia/economia , Biópsia/métodos , Corantes/economia , Controle de Custos , Custos de Cuidados de Saúde , Recursos em Saúde , Humanos , Patologistas/ética , Patologia Clínica/métodos , Relações Médico-Paciente
6.
Int J Dermatol ; 55(4): e172-5, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26861859

RESUMO

BACKGROUND: The diagnosis of superficial mycosis such as dermatophytosis is often done clinically. However, in difficult cases, a rapid test with high sensitivity and specificity helps in the immediate confirmation and administration of treatment. METHODS: The efficacy, rapidity of detection, and cost-effectiveness of KOH preparation, calcofluor white (CW) stain, and Chicago sky blue (CSB) stain in the identification of fungal elements were assessed in patients with dermatophytoses attending the dermatology clinic of a tertiary care hospital. All three tests were performed on each sample collected from 73 patients according to standard procedure. The slides were examined after 5 and 30 minutes in × 10 and × 40 magnifications. The sensitivity and specificity of CW and CSB at 5 and 30 minutes were calculated using KOH preparation as the standard test. RESULTS: CSB stain showed highest positivity (94.5%) within 5 minutes when compared to KOH (75.3%) and CW (83.5%). After 30 minutes, positivity increased in KOH (84.9%) and CW stains (89%), but it remained the same in CSB stain. Both CW and CSB stains when compared to 10% KOH are equally sensitive (100%), but CW was more specific (72.7%), particularly at 30 minutes. When cost of performing tests on 100 specimens is considered, KOH, CW, and CSB stains cost Rs 5, 100, and 15, respectively. CONCLUSION: CSB stain is a better stain for rapid diagnosis of dermatophytoses because of ease of performance, rapidity of detection, better appreciation of morphology of fungal elements, and cost effectiveness.


Assuntos
Benzenossulfonatos , Corantes , Hidróxidos , Compostos de Potássio , Coloração e Rotulagem/métodos , Tinha/diagnóstico por imagem , Azul Tripano , Adolescente , Adulto , Idoso , Benzenossulfonatos/economia , Criança , Pré-Escolar , Corantes/economia , Análise Custo-Benefício , Feminino , Humanos , Hidróxidos/economia , Masculino , Microscopia , Pessoa de Meia-Idade , Compostos de Potássio/economia , Valor Preditivo dos Testes , Coloração e Rotulagem/economia , Fatores de Tempo , Azul Tripano/economia , Adulto Jovem
7.
Biotech Histochem ; 90(6): 461-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26140654

RESUMO

Eriochrome cyanine R (ECR) is a synthetic anionic dye that forms complexes with cations such as iron. We found that an iron-ECR (Fe-ECR) mixture provided either nuclear or myelin staining depending on the differentiator used. Selective nuclear staining was obtained by differentiation in an aqueous HCl solution, pH 0.95, followed by a wash in slightly alkaline tap water; the pH difference facilitated control of differentiation. When used with an eosin B counterstain, results were nearly indistinguishable from standard hematoxylin and eosin (H & E) staining. Nuclear staining with Fe-ECR provides tinctorial features similar to regressive aluminum-hemateins as well as resistance to acidic solutions such as those of iron hemateins. Fe-ECR also stained selectively intestinal cells of the diffuse neuroendocrine system (DNES). In addition to its use as an H & E substitute, acid differentiated Fe-ECR produced acid-resistant and selective nuclear counterstaining in combination with Alcian blue, and in the Papanicolaou and van Gieson techniques. With alkali differentiation, Fe-ECR produced selective myelin staining, which was compatible with neutral red counterstaining. Myelin sheaths were stained aqua blue. Fe-ECR could be used for both cytological and histological samples, and was suitable for use in automated tissue stainers. ECR also is less expensive than hematoxylin. Hematoxylin still may be preferred as a nuclear counterstain for some immunostaining methods for which Fe-ECR mixtures probably are too acidic.


Assuntos
Benzenossulfonatos , Corantes , Hematoxilina , Coloração e Rotulagem/métodos , Azul Alciano , Animais , Benzenossulfonatos/economia , Núcleo Celular/metabolismo , Corantes/economia , Custos e Análise de Custo , Hematoxilina/economia , Histocitoquímica/economia , Histocitoquímica/métodos , Humanos , Concentração de Íons de Hidrogênio , Ferro , Bainha de Mielina/metabolismo , Coloração e Rotulagem/economia , Sus scrofa
8.
BMJ ; 351: h3084, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26142020

RESUMO

OBJECTIVE: To assess and compare the accuracy of visual inspection with acetic acid (VIA), visual inspection with Lugol's iodine (VILI), and human papillomavirus (HPV) testing as alternative standalone methods for primary cervical cancer screening in sub-Saharan Africa. DESIGN: Systematic review and meta-analysis of diagnostic test accuracy studies. DATA SOURCES: Systematic searches of multiple databases including Medline, Embase, and Scopus for studies published between January 1994 and June 2014. REVIEW METHODS: Inclusion criteria for studies were: alternative methods to cytology used as a standalone test for primary screening; study population not at particular risk of cervical cancer (excluding studies focusing on HIV positive women or women with gynaecological symptoms); women screened by nurses; reference test (colposcopy and directed biopsies) performed at least in women with positive screening results. Two reviewers independently screened studies for eligibility and extracted data for inclusion, and evaluated study quality using the quality assessment of diagnostic accuracy studies 2 (QUADAS-2) checklist. Primary outcomes were absolute accuracy measures (sensitivity and specificity) of screening tests to detect cervical intraepithelial neoplasia grade 2 or worse (CIN2+). RESULTS: 15 studies of moderate quality were included (n=61,381 for VIA, n=46,435 for VILI, n=11,322 for HPV testing). Prevalence of CIN2+ did not vary by screening test and ranged from 2.3% (95% confidence interval 1.5% to 3.3%) in VILI studies to 4.9% (2.7% to 7.8%) in HPV testing studies. Positivity rates of VILI, VIA, and HPV testing were 16.5% (9.8% to 24.7%), 16.8% (11.0% to 23.6%), and 25.8% (17.4% to 35.3%), respectively. Pooled sensitivity was higher for VILI (95.1%; 90.1% to 97.7%) than VIA (82.4%; 76.3% to 87.3%) in studies where the reference test was performed in all women (P<0.001). Pooled specificity of VILI and VIA were similar (87.2% (78.1% to 92.8%) v 87.4% (77.1% to 93.4%); P=0.85). Pooled sensitivity and specificity were similar for HPV testing versus VIA (both P ≥ 0.23) and versus VILI (both P ≥ 0.16). Accuracy of VIA and VILI increased with sample size and time period. CONCLUSIONS: For primary screening of cervical cancer in sub-Saharan Africa, VILI is a simple and affordable alternative to cytology that demonstrates higher sensitivity than VIA. Implementation studies are needed to assess the effect of these screening strategies on the incidence and outcomes of cervical cancer in the region.


Assuntos
Ácido Acético , Corantes , Detecção Precoce de Câncer/métodos , Iodetos , Programas de Rastreamento/métodos , Infecções por Papillomavirus/diagnóstico , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Ácido Acético/economia , Adulto , África Subsaariana/epidemiologia , Corantes/economia , Análise Custo-Benefício , Detecção Precoce de Câncer/economia , Feminino , Humanos , Iodetos/economia , Programas de Rastreamento/economia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/economia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/economia , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal/economia , Displasia do Colo do Útero/economia , Displasia do Colo do Útero/virologia
9.
World J Gastroenterol ; 21(18): 5513-23, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25987774

RESUMO

AIM: To study the cost-effectiveness of high-resolution microendoscopy (HRME) in an esophageal squamous cell carcinoma (ESCC) screening program in China. METHODS: A decision analytic Markov model of ESCC was developed. Separate model analyses were conducted for cohorts consisting of an average-risk population or a high-risk population in China. Hypothetical 50-year-old individuals were followed until age 80 or death. We compared three different strategies for both cohorts: (1) no screening; (2) standard endoscopic screening with Lugol's iodine staining; and (3) endoscopic screening with Lugol's iodine staining and an HRME. Model parameters were estimated from the literature as well as from GLOBOCAN, the Cancer Incidence and Mortality Worldwide cancer database. Health states in the model included non-neoplasia, mild dysplasia, moderate dysplasia, high-grade dysplasia, intramucosal carcinoma, operable cancer, inoperable cancer, and death. Separate ESCC incidence transition rates were generated for the average-risk and high-risk populations. Costs in Chinese currency were converted to international dollars (I$) and were adjusted to 2012 dollars using the Consumer Price Index. RESULTS: The main outcome measurements for this study were quality-adjusted life years (QALYs) and incremental cost-effectiveness ratio (ICER). For the average-risk population, the HRME screening strategy produced 0.043 more QALYs than the no screening strategy at an additional cost of I$646, resulting in an ICER of I$11808 per QALY gained. Standard endoscopic screening was weakly dominated. Among the high-risk population, when the HRME screening strategy was compared with the standard screening strategy, the ICER was I$8173 per QALY. For both the high-risk and average-risk screening populations, the HRME screening strategy appeared to be the most cost-effective strategy, producing ICERs below the willingness-to-pay threshold, I$23500 per QALY. One-way sensitivity analysis showed that, for the average-risk population, higher specificity of Lugol's iodine (> 40%) and lower specificity of HRME (< 70%) could make Lugol's iodine screening cost-effective. For the high-risk population, the results of the model were not substantially affected by varying the follow-up rate after Lugol's iodine screening, Lugol's iodine test characteristics (sensitivity and specificity), or HRME specificity. CONCLUSION: The incorporation of HRME into an ESCC screening program could be cost-effective in China. Larger studies of HRME performance are needed to confirm these findings.


Assuntos
Carcinoma de Células Escamosas/economia , Carcinoma de Células Escamosas/patologia , Detecção Precoce de Câncer/economia , Neoplasias Esofágicas/economia , Neoplasias Esofágicas/patologia , Esofagoscopia/economia , Custos de Cuidados de Saúde , Microscopia/economia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , China/epidemiologia , Corantes/economia , Análise Custo-Benefício , Detecção Precoce de Câncer/métodos , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago , Esofagoscopia/métodos , Feminino , Humanos , Aumento da Imagem , Iodetos/economia , Masculino , Cadeias de Markov , Microscopia/métodos , Pessoa de Meia-Idade , Modelos Econômicos , Valor Preditivo dos Testes , Prognóstico , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Estudos Retrospectivos , Fatores de Tempo
12.
J Food Sci ; 79(2): E184-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24472095

RESUMO

This study investigated purification of anthocyanins from black bean canning wastewater by column chromatography with 5 types of macroporous resins (Diaion Hp20, Sepabeads Sp70, Sepabeads Sp207, Sepabeads Sp700, and Sepabeads Sp710). By-product of canned black beans was partially purified by filtration, in anticipation of higher performance during column chromatography. Equilibrium adsorption isotherms were measured and analyzed using Langmuir and Freundlich isotherm models. Both Langmuir (all R² ≥ 0.98) and Freundlich (all R² ≥ 0.97) models can describe the adsorption process of anthocyanins from black bean canning wastewater using the tested resins. The adsorption and desorption behaviors of anthocyanins were studied using a dynamic method on the 5 types of resins, and Sp700 presented the highest adsorption capacity (39 ± 4 mg/g; P < 0.05) as well as desorption capacity (19 ± 2%; P < 0.05), indicating that of the resins examined, Sp700 is a better candidate for purification of anthocyanins from black bean canning wastewater.


Assuntos
Antocianinas/isolamento & purificação , Corantes/isolamento & purificação , Fabaceae/química , Modelos Químicos , Sementes/química , Adsorção , Antocianinas/análise , Antocianinas/química , Antocianinas/economia , Cromatografia Líquida , Corantes/análise , Corantes/química , Corantes/economia , Conservação de Alimentos/economia , Indústria de Processamento de Alimentos/economia , Cinética , Porosidade , Resinas Sintéticas/química , Solubilidade , Águas Residuárias/química , Águas Residuárias/economia
13.
J Pak Med Assoc ; 63(7): 835-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23901703

RESUMO

OBJECTIVE: To use toluidine blue intra-operatively to identify tumour involved margins after the removal of oral cavity squamous cell carcinoma, and to compare the findings with those of final histopathology. METHODS: The study was conducted at the Aga Khan University Hospital from December 1, 2009, to March 14, 2010, and comprised 56 consecutive patients with biopsy-proven squamous cell carcinoma of oral cavity regardless of grade and stage of tumour. Intra-operatively toluidine blue was used on the resected tumour margins and the staining patterns were assessed. Results were then compared with the final histopathology report. RESULTS: A total of 11(19.64%) margins were positive with toluidine blue staining out of which 8 (14.28%) were false positive. Sensitivity and specificity was found to be 100% and 84.9% respectively with a positive predictive value of 27.2%; a negative predictive value of 100%; and diagnostic accuracy of 85.71%. CONCLUSION: Toluidine blue costs only Rs25 (USD 0.30) and takes only 5 minutes for application and interpretation. It can be used with significant confidence in smaller lesions (T-l and T-II) as an alternative to frozen sections in developing countries where facilities are unavailable. Its use in larger lesions (T-lll and TIV) remains the topic of controversy and awaits a multi centre trial with a larger cohort.


Assuntos
Biópsia/economia , Carcinoma de Células Escamosas/diagnóstico , Países em Desenvolvimento , Detecção Precoce de Câncer/economia , Neoplasias Bucais/diagnóstico , Estadiamento de Neoplasias/métodos , Cloreto de Tolônio , Carcinoma de Células Escamosas/economia , Carcinoma de Células Escamosas/epidemiologia , Corantes/economia , Análise Custo-Benefício , Estudos Transversais , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/economia , Neoplasias Bucais/epidemiologia , Estadiamento de Neoplasias/economia , Paquistão/epidemiologia , Projetos Piloto , Prevalência , Estudos Prospectivos , Cloreto de Tolônio/economia
14.
Artigo em Inglês | MEDLINE | ID: mdl-23832227

RESUMO

This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k=1.6, 2.1 and 1.9×10(-3)min(-1) for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100mWcm(-2), reveals highly stable DSSCs.


Assuntos
Corantes/química , Corantes/economia , Luz , Energia Solar/economia , Absorção , Antocianinas/química , Antocianinas/economia , Cor , Custos e Análise de Custo , Cumarínicos/química , Cumarínicos/economia , Eletrodos , Cinética , Microscopia Eletrônica de Transmissão , Titânio/química , Difração de Raios X
15.
Int J Dermatol ; 51(8): 935-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22788809

RESUMO

BACKGROUND: The cheapest, most rapid method for the diagnosis of mycotic skin and nail infections is direct examination of samples using a KOH preparation. The standard KOH wet mount lacks a color contrast. Various contrast dyes are available. Parker ink is one which has been extensively used, however in recent times the stain no longer provides a suitable color contrast. Two other dyes that are available are Chicago blue and chlorazole black. METHODS: 100 samples of skin or nails were prospectively examined using Chicago blue, chlorazole black, and Parker ink-KOH stains. The samples were also cultured, with culture being the diagnostic gold standard. RESULTS: The sensitivities and specificities of the Chicago blue, chlorazole black and Parker ink stains were 78% & 96%; 63% & 97%; and 48% and 96%, respectively. CONCLUSION: The Chicago blue-KOH stain provides a good color contrast and is a suitable replacement for the Parker ink-KOH stain. It is suitable for use in the dermatologist's office or in the laboratory.


Assuntos
Álcoois/química , Compostos Azo/química , Corantes/química , Dermatomicoses/diagnóstico , Formaldeído/química , Onicomicose/diagnóstico , Coloração e Rotulagem/métodos , Azul Tripano/química , Álcoois/economia , Compostos Azo/economia , Corantes/economia , Formaldeído/economia , Humanos , Hidróxidos/química , Hidróxidos/economia , Compostos de Potássio/química , Compostos de Potássio/economia , Estudos Prospectivos , Azul Tripano/economia
16.
Bot J Linn Soc ; 166(2): 185-211, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21941694

RESUMO

This is an historical and descriptive account of 28 herbarium specimens, 27 lichens and an alga, found in the archives of Charles Chalcraft, a descendant of the Bedford family, who were dye manufacturers in Leeds, England, in the 19th century. The lichens comprise 13 different morphotypes collected in the Canary Islands and West Africa by the French botanist J. M. Despréaux between 1833 and 1839. The collections include samples of "Roccella fuciformis", "R. phycopsis" and "R. tinctoria" (including the fertile morphotype "R. canariensis"), "Ramalina crispatula" and "R. cupularis", two distinct morphotypes of "Sticta", "S. canariensis" and "S. dufouri", "Physconia enteroxantha", "Pseudevernia furfuracea var. ceratea" and "Pseudocyphellaria argyracea". The herbarium also includes authentic material of "Parmotrema tinctorum" and a probable syntype of "Seirophora scorigena". Most of these species are known as a source of the purple dye orchil, which was used to dye silk and wool.


Assuntos
Botânica , Vestuário , Corantes , Líquens , Manufaturas , África Ocidental/etnologia , Botânica/educação , Botânica/história , Vestuário/economia , Vestuário/história , Corantes/economia , Corantes/história , História do Século XIX , Manufaturas/economia , Manufaturas/história , Plantas Medicinais , Espanha/etnologia , Reino Unido/etnologia
17.
Anal Bioanal Chem ; 399(5): 1869-75, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21221552

RESUMO

This study investigates the use of thread as a flexible and low-cost substrate for the rapid grouping of blood. The use of a capillary substrate such as thread for blood grouping utilises the sensitivity of the flow resistance of large particles in narrow capillary channels to separate agglutinated red blood cells (RBCs) from plasma. Large and discrete particles formed in a continuous liquid phase do not provide capillary wicking driving force and fall behind the capillary wicking front, leading to their separation from the wicking liquid. The capillary substrate therefore provides a very promising but different mechanism for the separation of the agglutinated RBCs and the blood serum phase compared to most existing blood grouping methods. The principle of chromatographic separation is also exploited in this study via the use of suitable dyes to enhance the visual detection of the agglutinated RBCs and the serum phase; surprising and encouraging outcomes are obtained. Using a thread-based device, the ABO and Rh groups can be successfully determined with only 2 µL of whole blood from a pricked finger tip within 1 min and without pre-treatment of the blood sample. It is hoped that a new, inexpensive, rapid and simple method may provide an easy-to-use blood grouping platform well suited to those in developing or remote regions of the world.


Assuntos
Sistema ABO de Grupos Sanguíneos/sangue , Sistema ABO de Grupos Sanguíneos/economia , Anticorpos/química , Anticorpos/economia , Corantes/química , Corantes/economia , Imunofluorescência , Humanos , Sensibilidade e Especificidade
18.
Anal Biochem ; 406(1): 86-8, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20599644

RESUMO

Coomassie Brilliant Blue (CBB) protein stains are inexpensive but detect proteins at only at microgram levels. Because of acetic acid and methanol, they cause skin irritation and reduce work motivation by malodor. Recent mass spectrometric (MS) analyses demonstrated that nanogram-sensitive colloidal CBB staining resulted in in vitro methylations of proteins. We propose a rapid, inexpensive, sensitive, odorless, less harsh, and in vitro methylation-free CBB stain. CGP uses three components: citric acid, CBB G-250, and polyvinylpyrrolidone. CGP detects proteins at 12ng within 45min, and because it is nonalcohol, in principle in vitro methylation would be eliminated. Indeed, MS analysis of CGP-stained bands confirmed a lack of methylation.


Assuntos
Corantes/economia , Odorantes , Corantes de Rosanilina/economia , Coloração e Rotulagem/economia , Coloração e Rotulagem/métodos , Animais , Bovinos , Corantes/metabolismo , Corantes/toxicidade , Proteínas/metabolismo , Corantes de Rosanilina/metabolismo , Corantes de Rosanilina/toxicidade , Fatores de Tempo
19.
J Nat Prod ; 73(7): 1193-5, 2010 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-20565070

RESUMO

Antioxidants scavenge free radicals, singlet oxygen, and electrons in cellular redox reactions. The yellow MTT [3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide] is reduced to a purple formazan by mitochondrial enzymes. NADPH is the basis of established in vitro cell viability assays. An antioxidant assay has been developed utilizing the redox reaction between MTT and selected natural product extracts and purified compounds. This simple, fast, and inexpensive MTT antioxidant assay is comparable with the lipid peroxidation inhibitory assay and can be mechanized to achieve high throughput.


Assuntos
Antioxidantes/farmacologia , Corantes , Extratos Vegetais/farmacologia , Sais de Tetrazólio , Tiazóis , Antioxidantes/economia , Antioxidantes/metabolismo , Corantes/economia , Corantes/farmacologia , Formazans , Sequestradores de Radicais Livres/economia , Sequestradores de Radicais Livres/metabolismo , Sequestradores de Radicais Livres/farmacologia , Mitocôndrias/enzimologia , Estrutura Molecular , NADP/metabolismo , Oxirredução , Extratos Vegetais/economia , Extratos Vegetais/metabolismo , Oxigênio Singlete/química , Sais de Tetrazólio/economia , Tiazóis/economia
20.
J Biomol Screen ; 15(2): 213-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20042532

RESUMO

Chitin and its derivatives are widely used as biomedical materials because of their versatility and biocompatibility. Chitinases are enzymes that produce chito-oligosaccharides from chitin. The assay of chitinase activity is difficult because few appropriate substrates are available. In this study, the authors developed an efficient and low-cost chitinase assay using colloidal chitin azure. The assay feasibility is evaluated and compared with traditional assays employing colloidal chitin and chitin azure. The authors found that the optimum pH for determining chitinase activity using colloid chitin azure was pH 5 or 8. The method was sensitive, and the assay was complete within 30 min. When the assay was used to measure chitinase activities produced by 2 strains of chitinolytic bacteria, BCTS (an Escherichia coli BL21 [DE3] expressing a secretory recombinant chitinase) and AS1 (a chitinolytic bacterium with low levels of chitinase), it was shown that cultivation in Bushnell-Haas selection medium caused AS1 to secrete a higher level of chitinase than was secreted when the bacterium grew in other media. In summary, colloid chitin azure is a sensitive, feasible, reproducible, and low-cost substrate for the assay of chitinase activity.


Assuntos
Materiais Biocompatíveis/metabolismo , Bioensaio , Quitina/metabolismo , Quitinases/metabolismo , Corantes Azur/química , Corantes Azur/economia , Quitinases/análise , Quitinases/genética , Coloides , Corantes/química , Corantes/economia , Meios de Cultura/química , Escherichia coli/genética , Escherichia coli/metabolismo , Estudos de Viabilidade , Concentração de Íons de Hidrogênio , Cinética , Proteínas Recombinantes/análise , Proteínas Recombinantes/metabolismo , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade por Substrato , Fatores de Tempo
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