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1.
Lancet Digit Health ; 5(12): e905-e916, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38000874

RESUMO

BACKGROUND: Computer-aided detection (CADe) systems could assist endoscopists in detecting early neoplasia in Barrett's oesophagus, which could be difficult to detect in endoscopic images. The aim of this study was to develop, test, and benchmark a CADe system for early neoplasia in Barrett's oesophagus. METHODS: The CADe system was first pretrained with ImageNet followed by domain-specific pretraining with GastroNet. We trained the CADe system on a dataset of 14 046 images (2506 patients) of confirmed Barrett's oesophagus neoplasia and non-dysplastic Barrett's oesophagus from 15 centres. Neoplasia was delineated by 14 Barrett's oesophagus experts for all datasets. We tested the performance of the CADe system on two independent test sets. The all-comers test set comprised 327 (73 patients) non-dysplastic Barrett's oesophagus images, 82 (46 patients) neoplastic images, 180 (66 of the same patients) non-dysplastic Barrett's oesophagus videos, and 71 (45 of the same patients) neoplastic videos. The benchmarking test set comprised 100 (50 patients) neoplastic images, 300 (125 patients) non-dysplastic images, 47 (47 of the same patients) neoplastic videos, and 141 (82 of the same patients) non-dysplastic videos, and was enriched with subtle neoplasia cases. The benchmarking test set was evaluated by 112 endoscopists from six countries (first without CADe and, after 6 weeks, with CADe) and by 28 external international Barrett's oesophagus experts. The primary outcome was the sensitivity of Barrett's neoplasia detection by general endoscopists without CADe assistance versus with CADe assistance on the benchmarking test set. We compared sensitivity using a mixed-effects logistic regression model with conditional odds ratios (ORs; likelihood profile 95% CIs). FINDINGS: Sensitivity for neoplasia detection among endoscopists increased from 74% to 88% with CADe assistance (OR 2·04; 95% CI 1·73-2·42; p<0·0001 for images and from 67% to 79% [2·35; 1·90-2·94; p<0·0001] for video) without compromising specificity (from 89% to 90% [1·07; 0·96-1·19; p=0·20] for images and from 96% to 94% [0·94; 0·79-1·11; ] for video; p=0·46). In the all-comers test set, CADe detected neoplastic lesions in 95% (88-98) of images and 97% (90-99) of videos. In the benchmarking test set, the CADe system was superior to endoscopists in detecting neoplasia (90% vs 74% [OR 3·75; 95% CI 1·93-8·05; p=0·0002] for images and 91% vs 67% [11·68; 3·85-47·53; p<0·0001] for video) and non-inferior to Barrett's oesophagus experts (90% vs 87% [OR 1·74; 95% CI 0·83-3·65] for images and 91% vs 86% [2·94; 0·99-11·40] for video). INTERPRETATION: CADe outperformed endoscopists in detecting Barrett's oesophagus neoplasia and, when used as an assistive tool, it improved their detection rate. CADe detected virtually all neoplasia in a test set of consecutive cases. FUNDING: Olympus.


Assuntos
Esôfago de Barrett , Aprendizado Profundo , Neoplasias Esofágicas , Humanos , Esôfago de Barrett/diagnóstico , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patologia , Esofagoscopia/métodos , Razão de Chances
2.
Endosc Int Open ; 11(10): E992-E1000, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37854124

RESUMO

Background and study aims Simethicone is useful as premedication for upper endoscopy because of its antifoaming effects. We aimed to evaluate the effect of timing of simethicone administration on mucosal visibility. Patients and methods In this multicenter, randomized, endoscopist-blinded study, patients scheduled for upper endoscopy were randomized to receive 40 mg simethicone at the following time points prior to the procedure: 20 to 30 minutes (early group), 0 to 10 minutes (late group) or 20 mg simethicone at both time points (split-dose group). Images were taken from nine predefined locations in the esophagus, stomach, and duodenum before endoscopic flushing. Each image was scored on mucosal visibility by three independent endoscopists on a 4-point scale (lower scores indicating better visibility), with adequate mucosal visibility defined as a score ≤ 2. Primary outcome was the percentage of patients with adequate total mucosal visibility (TMV), reached if all median subscores for each location were ≤ 2. Results A total of 386 patients were included (early group: 132; late group: 128; split-dose group: 126). Percentages of adequate TMV were 55%, 42%, and 61% in the early, late, and split-dose group, respectively ( P < 0.01). Adequate TMV was significantly higher in the split-dose group compared to the late group ( P < 0.01), but not compared to the early group ( P = 0.29). Differences between groups were largest in the stomach, where percentages of adequate mucosal visibility were higher in the early (68% vs 53%, P = 0.03) and split-dose group (69% vs 53%, P = 0.02) compared to the late group. Conclusions Mucosal visibility can be optimized with early simethicone administration, either as a single administration or in a split-dose regimen.

6.
Forensic Sci Int ; 329: 111087, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34736052

RESUMO

An important demand exists in the field of forensic analysis to objectively determine the post-mortem interval (PMI) when human skeletal remains are discovered. It is widely known that bones undergo different chemical and physical processes after death, mainly due to their interaction with the environment in which they are found, although it is not known exactly what these processes consist of. Multiple techniques have been used so far to follow up these and other post-mortem changes and thus establish the time elapsed since the individual's death, but they present important drawbacks in terms of reliability and accuracy. The aim of this research was to propose an analytical methodology capable of determining the PMI by using non-destructive Raman spectroscopy measurements of human skeletal remains. The recorded Raman spectra provided valuable and potentially useful information from which a multivariate study was performed by means of orthogonal partial least squares regression (OPLSR) in order to correlate the PMI with the detected spectral modifications. A collection of 53 real human skeletal remains with known PMI (15 years ≤ PMI ≤ 87 years) was analysed and used for building and validating the OPLS model. The PMI of 10 out of 14 validation samples could be determined with an accuracy error of less than 30%, demonstrating the adequate predictive performance of the OPLS model even in spite of the large inter-individual variability it handled. This opens up the possibility of applying the OPLS model in combination with non-destructive techniques to the determination of the PMI of human skeletal remains that have been buried in conditions similar or equal to those of cemetery niches and in a geographic location with a Mediterranean climate, which is an important achievement for forensic medicine and anthropology.


Assuntos
Restos Mortais , Análise Espectral Raman , Quimiometria , Humanos , Mudanças Depois da Morte , Reprodutibilidade dos Testes
7.
J Gastrointest Surg ; 25(1): 67-76, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33140322

RESUMO

INTRODUCTION: After endoscopic resection (ER) of neoplasia in Barrett's esophagus (BE), it is recommended to ablate the remaining BE to minimize the risk for metachronous disease. However, we report long-term outcomes for a nationwide cohort of all patients who did not undergo ablation of the remaining BE after ER for early BE neoplasia, due to clinical reasons or performance status. METHODS: Endoscopic therapy for BE neoplasia in the Netherlands is centralized in 8 expert centers with specifically trained endoscopists and pathologists. Uniformity is ensured by a joint protocol and regular group meetings. We report all patients who underwent ER for a neoplastic lesion between 2008 and 2018, without further ablation therapy. Outcomes include progression during endoscopic FU and all-cause mortality. RESULTS: Ninety-four patients were included with mean age 74 (± 10) years. ER was performed for low-grade dysplasia (LGD) (10%), high-grade dysplasia (HGD) (25%), or low-risk esophageal adenocarcinoma (EAC) (65%). No additional ablation was performed for several reasons; in 73 patients (78%), the main argument was expected limited life expectancy. Median C2M5 BE persisted after ER, and during median 21 months (IQR 11-51) with 4 endoscopies per patient, no patient progressed to advanced cancer. Seventeen patients (18%) developed HGD/EAC: all were curatively treated endoscopically. In total, 29/73 patients (40%) with expected limited life expectancy died due to unrelated causes during FU, none of EAC. CONCLUSION: In selected patients, ER monotherapy with endoscopic surveillance of the residual BE is a valid alternative to eradication therapy with ablation.


Assuntos
Adenocarcinoma , Esôfago de Barrett , Ablação por Cateter , Neoplasias Esofágicas , Lesões Pré-Cancerosas , Adenocarcinoma/cirurgia , Idoso , Esôfago de Barrett/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagoscopia , Humanos , Países Baixos/epidemiologia , Lesões Pré-Cancerosas/cirurgia
10.
Talanta ; 205: 120114, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450424

RESUMO

In recent years the interest and demand for artworks has been increasing as they are an interesting commercial investment due to their growing value in the market. This explains the increasing number of counterfeits dealing with artworks that has led to the development of new methodologies for their characterization. The material characterization of these types of works can provide relevant information for both authentication and conservation/restoration. Thus, in this study multivariate chemometric methods were applied to FTIR-ATR spectroscopic data for artwork dating purposes. To that end, ageing prediction models were developed for Liquitex® and Hyplar® brands. Paint samples containing the green synthetic organic pigment (PG7), were exposed to artificial ageing and analysed with FTIR-ATR and Py-GC/MS for characterization and monitorization of the main components (binding medium, pigment and additives). Although the OPLS ageing models were mainly characterized by the modifications suffered by both the binder and the surfactants, a universal model could not be developed due to differences in the modification trends of the different brands. The applicability of the OPLS modelling for artwork dating purposes was tested in artworks provided by internationally recognized contemporary Basque artists. For Liquitex® a significant correlation (p < 0.05) between natural and accelerated ageing could be established, in which approximately 50 h of accelerated ageing under the applied conditions were equivalent to one natural year. This correlation might have possible applications in the dating of artworks for up to at least 22 years. Thus, the study demonstrates that FTIR-ATR combined with chemometrics is a potential method for artwork dating and a valuable source of information about the chemical processes involved in paint ageing, which can be of great help in the conservation and restoration steps.

11.
Pediatr. aten. prim ; 19(74): 163-166, abr.-jun. 2017. tab
Artigo em Espanhol | IBECS | ID: ibc-164181

RESUMO

El hipertiroidismo en la infancia es muy infrecuente; en la mayoría de los casos es de origen autoinmune (enfermedad de Graves). La tríada clásica se compone de bocio, oftalmopatía y dermatopatía. Su presentación clínica en la edad pediátrica es muy variable y de comienzo habitualmente insidioso, lo que en muchas ocasiones conlleva una demora en el diagnóstico y tratamiento. Presentamos el caso de una paciente de 12 años que consulta por una conjuntivitis crónica bilateral refractaria a tratamientos tópicos habituales, que finalmente fue derivada al Servicio de Endocrinología Pediátrica ante la sospecha de oftalmopatía de Graves (AU)


Hyperthyroidism in childhood is a very rare condition, and in most cases of autoimmune etiology (Graves’ disease). The classic triad consists of goiter, ophthalmopathy and dermopathy. Clinical presentation in children is highly variable and often with an insidious onset, which on many occasions may cause a delay on its diagnosis and treatment. A case is reported here where a 12-year-old patient, who showed a refractory bilateral chronic conjunctivitis refractary to topical usual treatments, was finally referred to the Pediatric Endocrinology Department due to the likelihood of her suffering from Graves' ophthalmopathy (AU)


Assuntos
Humanos , Feminino , Criança , Conjuntivite/complicações , Conjuntivite/diagnóstico , Recidiva , Doença de Graves/complicações , Hipertireoidismo/complicações , Antagonistas dos Receptores Histamínicos/uso terapêutico , Ceratite/complicações , Oftalmopatia de Graves/complicações , Oftalmopatia de Graves/diagnóstico , Crise Tireóidea/complicações , Ceratite/diagnóstico , Diagnóstico Diferencial
12.
Talanta ; 146: 326-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26695271

RESUMO

A rapid and sensitive analytical method for the simultaneous determination of thirteen endocrine disruptors (five phthalates, seven parabens, and bisphenol A) in a single chromatographic run has been developed for the first time. The separation method, based on ultra-high performance liquid chromatography (UHPLC), allows the separation of all compounds (including isobaric pairs) in less than 4.1 min. The fast polarity switching mode of the triple quadrupole mass spectrometer used enables the registration of positive (phthalates) and negative (parabens and BPA) ions in the same acquisition run. A Response Surface Methodology was used for the optimization of the method. The optimum elution program starts with 0.2 min in isocratic conditions (79.8% water; 20% acetonitrile, 0.2% ammonium formate 5mM at pH 10.2), then the content of acetonitrile is linearly increased in 2 min up to 42%, and later up to 98% in 1.1 min. The analytical characteristics of the developed method were satisfactory. The method is robust and showed a linear response with determination coefficients (R(2)) higher than 0.991 in the range 5.0-2000 pg on column (or higher) for all the compounds investigated. Instrumental intra- and inter-day precision (expressed as relative standard deviation) were lower than 12% for parabens and bisphenol A, and between 5.9% and 27% for phthalates. Instrumental detection and quantification limits (iLODs and iLOQs) were in the range of medium-high femtograms (270-1300 pg on column for iLODs). Finally, the suitability of the developed method was demonstrated through its application to the analysis of commercial personal care products (shower gels) without any sample treatment, only a simple dilution, being possible to determine the simultaneous presence of phthalates, parabens, and bisphenol A in almost all the gels analyzed.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Disruptores Endócrinos/análise , Espectrometria de Massas em Tandem/métodos , Cosméticos/química , Disruptores Endócrinos/química , Fatores de Tempo
13.
Dis Esophagus ; 28(1): 25-31, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25756175

RESUMO

Radiofrequency ablation (RFA) is safe and effective for eradication of Barrett's esophagus after endoscopic resection (ER) of neoplasia. Widespread ER, however, is likely to induce stenosis, hampering subsequent circumferential RFA. A 'single step' procedure with ER and circumferential RFA in the same session may avoid this problem. Two variants are possible: circumferential RFA of Barrett's esophagus including the lesion followed by ER of the ablated lesion ('RFA→ER'), or ER of the lesion directly followed by circumferential RFA of remaining Barrett's esophagus including the resection wound ('ER→RFA'). First aim was to evaluate perforation risk of 'ER→RFA' using increasing RFA energies. Second aim was to compare stenosis rate after 'ER→RFA' versus 'RFA→ER'. In Experiment 1, 24 areas in six pigs underwent widespread ER directly followed by circumferential RFA with increasing energies (2 x 10, 2 x 12-6 x 12 J/cm(2)) in the esophagus. In Experiment 2, eight pigs each had four treatment areas randomized: 'ER→RFA', RFA alone, ER alone, and 'RFA→ER'. No acute perforations occurred when ablating ER wounds. Two delayed perforations occurred: one in experiment 1, another in experiment n2 at the 'ER→RFA' area. The remaining seven pigs in experiment 2 showed stenosis in all 'ER→RFA' and 'RFA→ER' areas versus 5/7 RFA alone areas, and 0/7 ER alone areas. In conclusion, the 'single step' variant 'ER→RFA' is not safe in this porcine model and seems therefore not ethical to evaluate in humans at this stage. Given the high rate of stenosis after 'RFA→ER' and RFA alone, one might question the validity of the porcine model for this type of experiments.


Assuntos
Esôfago de Barrett/cirurgia , Ablação por Cateter/efeitos adversos , Neoplasias Esofágicas/cirurgia , Perfuração Esofágica/etiologia , Estenose Esofágica/etiologia , Esofagoscopia/efeitos adversos , Animais , Ablação por Cateter/métodos , Terapia Combinada , Perfuração Esofágica/epidemiologia , Estenose Esofágica/epidemiologia , Esofagoscopia/métodos , Modelos Animais , Risco , Suínos , Resultado do Tratamento
14.
Dis Esophagus ; 28(7): 603-11, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24712765

RESUMO

Preliminary data show higher stricture rates after radiofrequency ablation (RFA) for early esophageal squamous neoplasia compared with Barrett's esophagus. We studied the effects of Lugol stain (LS) directly prior to RFA on stricture formation in squamous epithelium. Of 16 pigs, the distal half of the esophagus was LS, followed by circumferential RFA (single application 12 J/cm(2) ) in the unstained and stained esophagus. Pigs were euthanized at day 0 (n = 4), 3 (n = 4), or 28 (n = 8). Histology was evaluated in four areas: blank-control (no RFA, no LS), blank-RFA (no LS), LS+RFA, and LS-control (no RFA). Stenosis severity in LS+RFA and blank-RFA at 28 days was assessed by the ratio of the mucosal diameter at the RFA area to the diameter 2 cm proximal of this zone. Histology showed submucosal edema in 50% of LS+RFA versus 0% in blank-RFA. Severity and depth of inflammation (day 3) was equal in LS+RFA and blank-RFA. Severity and depth of fibrosis (day 28) appeared more severe in LS+RFA. Consequently, stenosis was present in 100% (LS+RFA) versus 12.5% (blank-RFA). The stenosis-severity ratio was 0.40 (interquartile range 0.29-0.45) in LS+RFA versus 0.73 (interquartile range 0.64-0.78) in blank-RFA (P = 0.012). Limitations of this study were the difference in uptake of LS between pigs and humans, the difference in esophageal anatomy between pigs and humans, and between the proximal and distal esophagus within pigs. In conclusion, in the porcine squamous esophagus, stenosis rate and severity after RFA increased when preceded by LS. LS may be contributing in the altered response of squamous epithelium to RFA as compared with Barrett's esophagus.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Ablação por Cateter/efeitos adversos , Corantes/efeitos adversos , Neoplasias Esofágicas/cirurgia , Estenose Esofágica/etiologia , Iodetos/efeitos adversos , Animais , Carcinoma de Células Escamosas/patologia , Ablação por Cateter/métodos , Epitélio/patologia , Epitélio/cirurgia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Estenose Esofágica/patologia , Esôfago/efeitos dos fármacos , Esôfago/cirurgia , Modelos Animais , Índice de Gravidade de Doença , Suínos , Resultado do Tratamento
15.
Surg Endosc ; 29(9): 2651-60, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25480614

RESUMO

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) is technically demanding. A viscous gel for submucosal lifting might induce mechanical submucosal dissection facilitating easier and safer ESD. METHODS: In 12 female pigs (median 64 kg), ESDs of simulated lesions were performed at the posterior wall and greater curvature in the gastric body (one ESD per location) with randomly assigned injection fluids: gel or control fluid (0.9% saline with hydroxypropyl methylcellulose 3 mg/ml [7:1] and indigo carmine droplets). Additionally, 10 cc gel was injected into the submucosa at the anterior wall without ESD to assess effects of inappropriate injection. Pigs were euthanized at day 0, 3 or 28. In four additional pigs (euthanized day 3 or 28) 10 cc gel was injected into the muscularis propria (MP) after four endoscopic mucosal resections in the gastric body. RESULTS: Both fluid groups showed equal ESD-procedure times (28 [gel] vs. 26 min [control]) and complications. Gel-ESDs required less accessory interchanges (3.5 vs. 5.5; p = 0.01). Mechanical dissection after circumferential incision was achieved in 25% of gel-ESDs; none in control-ESDs. The severity of inflammation and fibrosis was equal in both fluid groups. Normal architecture and vital mucosa were found after inappropriate submucosal injection. MP-injections resulted in one transmural hematoma (day 3), and intramuscular encapsulation in 25% of the sites (day 28). LIMITATIONS: A pig's stomach differs from the human stomach. CONCLUSIONS: The mechanical dissection properties of the gel may reduce the need for submucosal dissection during ESD. The gel is safe when advertently injected in the submucosa and MP. The porcine model appeared suboptimal to evaluate the true mechanical dissection properties of the gel.


Assuntos
Dissecação/métodos , Endoscopia Gastrointestinal , Mucosa Gástrica/cirurgia , Géis/administração & dosagem , Viscossuplementos/administração & dosagem , Animais , Feminino , Injeções , Modelos Animais , Suínos
16.
Int J Oral Maxillofac Implants ; 29(2): 311-20, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24683556

RESUMO

PURPOSE: This study aimed to compare the values of removal torque (RT) and bone-implant contact (BIC) reported in different animal studies for zirconia and titanium implants. MATERIALS AND METHODS: A systematic review of the literature was performed to analyze BIC and RT of animal studies in which both zirconia and titanium dental implants were used. To identify the studies to include in this systematic review, an exhaustive search of PubMed was performed of animal studies published in English with reports on the quantification of the osseointegration of both titanium and zirconia implants by means of BIC and/or RT. The results were aggregated and analyzed within each of the animal models (pig, rabbit, rat, monkey, dog, and sheep). RESULTS: The selection process resulted in a final sample of 16 studies. In general, no significant differences were found between titanium and zirconia. The significant differences in terms of BIC and RT reported by the authors were attributable to the different surface treatments and microporosities of the implant surfaces studied, not to the materials themselves. Only two articles reported significantly lower BIC for modified zirconia implants as compared to modified titanium implants. Four authors described statistically significant differences in terms of RT between zirconia and titanium implants in the different animal models, regardless of the surface treatment received by the implants. CONCLUSIONS: Within the limitations of this study, the values for the BIC and RT of zirconia implants in most of the studies analyzed did not show statistical differences compared with titanium implants. Modified-surface zirconia may have potential as a candidate for a successful implant material, although further clinical studies are necessary.


Assuntos
Implantes Dentários , Arcada Parcialmente Edêntula/cirurgia , Osseointegração , Animais , Materiais Biocompatíveis , Planejamento de Prótese Dentária , Cães , Haplorrinos , Modelos Animais , Coelhos , Ratos , Ovinos , Suínos , Titânio , Torque , Zircônio
17.
Environ Technol ; 34(9-12): 1267-81, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24191460

RESUMO

The potential of foundry sands, industrial waste from the iron foundry industry, was evaluated for the removal of Cr (VI) using discontinuous assays. Chemical foundry sands are composed of fine silica sand, furanic resins as binder, chemical catalyst and residual iron particles. The influence ofpH, agitation rate and metal concentration on the removal process was investigated. Kinetic and equilibrium tests were conducted to determine Cr (VI) removal from aqueous solutions at a temperature range of 25-55 degrees C. Cr (VI) removal of 40-100% for a range of pH 6-1.6 was obtained. This removal was attributed to the presence of a large number of protonated silanol and aluminol groups. Cr (VI) adsorption in foundry sands follows a pseudo-second-order kinetic reaction (Ho model, r2 > 0.999) reaching kinetic constants of 0.341, 0.551, 0.775 and 0.920 g/mg h at 25, 35, 45 and 55 degrees C, respectively. The adsorption data were fitted to the Langmuir adsorption isotherm model (r > 0.99) obtaining adsorption capacities (q(max)) of 1.99, 2.40, 2.50, and 3.14 mg Cr (VI)/g sand at 25, 35, 45 and 55 degrees C, respectively. Calculated Gibbs free energy change (deltaG0), adsorption energy (E) and activation energy (E(a)) values indicate that a physisorption mechanism governs Cr (VI) adsorption process in foundry sands.


Assuntos
Cromo/isolamento & purificação , Resíduos Industriais/análise , Dióxido de Silício/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Fracionamento Químico , Cromo/análise , Cromo/química , Concentração de Íons de Hidrogênio , Modelos Teóricos , Termodinâmica , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
18.
Anal Chim Acta ; 787: 148-54, 2013 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-23830433

RESUMO

Instrumental methods based on gas chromatography coupled to mass spectrometry (GC-MS) have been developed and compared using two different MS ionisation modes, electron impact (EI) and electron capture negative ionisation (ECNI), for the fast, quantitative and simultaneous determination of polychlorinated biphenyls (PCBs) and their main metabolites (hydroxylated PCBs, OH-PCBs, and methyl sulfone PCBs, MeSO2-PCBs). Parameters affecting chromatographic separation and MS detection were evaluated in order to achieve the highest selectivity and sensitivity for both operation modes. The analytical characteristics of the developed methods were studied and compared in terms of linear range, limits of detection (LODs), limits of quantification (LOQs), and instrumental precision (repeatability and intermediate precision). Both ionisation methods showed similar precision, being relative standard deviations (RSD, %) lower than 9% and 14% for repeatability and intermediate precision, respectively. However, better LODs (from 0.01 to 0.14 pg injected for the three families of congeners studied) were achieved using ECNI-MS as ionisation mode. The suitability of the developed method was demonstrated through their application to fish liver oil samples.


Assuntos
Óleos de Peixe/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Bifenilos Policlorados/análise , Dimetil Sulfóxido/análise , Hidroxilação , Sulfonas/análise , Fatores de Tempo
19.
Endoscopy ; 45(7): 516-25, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23580412

RESUMO

BACKGROUND AND STUDY AIMS: Radiofrequency ablation (RFA) is safe and effective for the eradication of neoplastic Barrett's esophagus; however, occasionally there is minimal regression after initial circumferential balloon-based RFA (c-RFA). This study aimed to identify predictive factors for a poor response 3 months after c-RFA, and to relate the percentage regression at 3 months to the final treatment outcome. METHODS: We included consecutive patients from 14 centers who underwent c-RFA for high grade dysplasia at worst. Patient and treatment characteristics were registered prospectively. "Poor initial response" was defined as < 50 % regression of the Barrett's esophagus 3 months after c-RFA, graded by two expert endoscopists using endoscopic images. Predictors of initial response were identified through logistic regression analysis. RESULTS: There were 278 patients included (median Barrett's segment C4M6). In poor initial responders (n = 36; 13 %), complete response for neoplasia (CR-neoplasia) was ultimately achieved in 86 % (vs. 98 % in good responders; P < 0.01) and complete response for intestinal metaplasia (CR-IM) in 66 % (vs. 95 %; P < 0.01). Poor responders required 13 months treatment (vs. 7 months; P < 0.01) for a median of four RFA sessions (vs. three; P < 0.01). We identified four independent baseline predictors of poor response: active reflux esophagitis (odds ratio [OR] 37.4; 95 % confidence interval [CI] 3.2 - 433.2); endoscopic resection scar regeneration with Barrett's epithelium (OR 4.7; 95 %CI 1.1 - 20.0); esophageal narrowing pre-RFA (OR 3.9; 95 %CI 1.0 - 15.1); and years of neoplasia pre-RFA (OR 1.2; 95 %CI 1.0 - 1.4). CONCLUSIONS: Patients with a poor initial response to c-RFA have a lower ultimate success rate for CR-neoplasia/CR-IM, require more treatment sessions, and a longer treatment period. A poor initial response to c-RFA occurs more frequently in patients who regenerate their endoscopic resection scar with Barrett's epithelium, and those with ongoing reflux esophagitis, neoplasia in Barrett's esophagus for a longer time, or a narrow esophagus.


Assuntos
Adenocarcinoma/cirurgia , Esôfago de Barrett/cirurgia , Ablação por Cateter , Neoplasias Esofágicas/cirurgia , Lesões Pré-Cancerosas/cirurgia , Adenocarcinoma/patologia , Idoso , Esôfago de Barrett/patologia , Ablação por Cateter/instrumentação , Ablação por Cateter/métodos , Técnicas de Apoio para a Decisão , Neoplasias Esofágicas/patologia , Esofagoscopia , Feminino , Seguimentos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Lesões Pré-Cancerosas/patologia , Estudos Prospectivos , Método Simples-Cego , Resultado do Tratamento
20.
Endoscopy ; 44(12): 1096-104, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23108809

RESUMO

BACKGROUND AND STUDY AIM: Endoscopic resection with radiofrequency ablation (RFA) 6 weeks later safely and effectively eradicates Barrett's esophagus with high grade dysplasia (HGD) and early cancer. After widespread endoscopic resection, related scarring may hamper balloon-based circumferential RFA (c-RFA). However c-RFA immediately followed by endoscopic resection in the same session might avoid the impact of scarring and reduce laceration and stenosis risk. We aimed to assess the feasibility of such an approach. PATIENTS AND METHODS: Patients with Barrett's esophagus ≥ 3 cm and ≥ 1 visible lesion (HGD/early cancer) were included. Visible lesions were marked with cautery, and c-RFA (12 J/cm2) was delivered using two applications and a cleaning step, followed by resection of the delineated area. Outcome measures were surface regression of Barrett's esophagus at 3 months, need for subsequent c-RFA, complications, and quality of resection specimens. RESULTS: 24 patients (20 men, 4 women; mean age 68 years, standard deviation [SD] 12; Barrett's esophagus median length C6M8) underwent single-session c-RFA + endoscopic resection, providing a median of 4 (interquartile range [IQR] 2 - 6) resection specimens (early cancer 18 patients; HGD 6). Complications included 1 perforation, 4 bleedings, and 5 stenoses; all were managed endoscopically. Specimens allowed assessment of neoplasia depth, differentiation, and lymphatic/vascular invasion. Median Barrett's esophagus surface regression at 3 months was 95 %. No patient required a second c-RFA procedure and 40 % required repeat endoscopic resection for visible lesions. Complete response for neoplasia was achieved in 100 % and complete response for intestinal metaplasia (CR-IM) in 95 %. CONCLUSIONS: c-RFA followed by endoscopic resection in the same session is feasible, but technically demanding and associated with a substantial rate of complications and repeat endoscopic resection. This approach should be reserved for selected cases in expert centers, with endoscopic resection and RFA 6 - 8 weeks later remaining the standard combined approach.


Assuntos
Esôfago de Barrett/patologia , Ablação por Cateter/métodos , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Esofagoscopia/métodos , Lesões Pré-Cancerosas/patologia , Idoso , Esôfago de Barrett/cirurgia , Biópsia por Agulha , Terapia Combinada , Intervalos de Confiança , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Países Baixos , Lesões Pré-Cancerosas/cirurgia , Estudos Prospectivos , Medição de Risco , Centros de Atenção Terciária , Resultado do Tratamento
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