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INTRODUCTION: Upper gastrointestinal (UGI) symptoms are very common in the general adult population. Dysphagia, heartburn, regurgitation and non-cardiac chest pain are the most common signs. The clinical approach in managing these symptoms starts with upper GI endoscopy in order to exclude inflammatory, neoplastic and fibrotic disorders that involve the esophagus. Upper GI endoscopy is mandatory especially when alarm signs exist. In patients with no structural abnormalities, physiological testing might aid to better understand the origin of the symptoms and to improve management.
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Monitorización del pH Esofágico , Manometría , Humanos , Manometría/métodos , Monitorización del pH Esofágico/métodos , Esófago/fisiopatología , Adulto , Endoscopía Gastrointestinal/métodos , Enfermedades del Esófago/diagnóstico , Enfermedades del Esófago/fisiopatología , Trastornos de Deglución/diagnóstico , Trastornos de Deglución/fisiopatología , Sulfato de Bario/administración & dosificaciónRESUMEN
Targeted delivery and retention are essential requirements for implantable tissue-engineered products. Non-invasive imaging methods that can confirm location, retention, and biodistribution of transplanted cells attached to implanted tissue engineering scaffolds will be invaluable for the optimization and enhancement of regenerative therapies. To address this need, an injectable tissue engineering scaffold consisting of highly porous microspheres compatible with transplantation of cells is modified to contain the computed tomography (CT) contrast agent barium sulphate (BaSO4). The trackable microspheres show high x-ray absorption, with contrast permitting whole-body tracking. The microspheres are cellularized with GFP+ Luciferase+ mesenchymal stem cells and show in vitro biocompatibility. In vivo, cellularized BaSO4-loaded microspheres are delivered into the hindlimb of mice where they remain viable for 14 days. Co-registration of 3D-bioluminescent imaging and µCT reconstructions enable the assessment of scaffold material and cell co-localization. The trackable microspheres are also compatible with minimally-invasive delivery by ultrasound-guided transthoracic intramyocardial injections in rats. These findings suggest that BaSO4-loaded microspheres can be used as a novel tool for optimizing delivery techniques and tracking persistence and distribution of implanted scaffold materials. Additionally, the microspheres can be cellularized and have the potential to be developed into an injectable tissue-engineered combination product for cardiac regeneration.
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Células Madre Mesenquimatosas , Microesferas , Ingeniería de Tejidos , Andamios del Tejido , Tomografía Computarizada por Rayos X , Animales , Andamios del Tejido/química , Ingeniería de Tejidos/métodos , Ratones , Ratas , Tomografía Computarizada por Rayos X/métodos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Sulfato de Bario/química , Medios de Contraste/químicaRESUMEN
RATIONALE: Barium peritonitis is an inflammatory response that occurs when barium accidentally enters the abdominal cavity during a barium test. In extreme circumstances, it has the potential to harm various organs and even result in death. PATIENT CONCERNS: A 3-month-old infant was diagnosed with multiple organ failure after severe barium peritonitis. DIAGNOSIS: Multiple organ dysfunction is associated with barium peritonitis. INTERVENTIONS: The infant underwent surgical intervention and received ventilator support, anti-infection therapy, myocardial nutrition, liver and kidney protection, rehydration, circulation stabilization, and other symptomatic supportive care. OUTCOMES: The patient experienced clinical death after treatment and resuscitation was unsuccessful. LESSONS: Barium enema perforation complications are uncommon, but can lead to fatal injuries with a high mortality rate. This case highlights the importance of raising awareness among clinicians about the risks of gastroenterography in infants and children and actively preventing and avoiding similar serious complications. The mortality rate can be reduced by timely multidisciplinary consultation and joint management once a perforation occurs.
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Perforación Intestinal , Insuficiencia Multiorgánica , Humanos , Lactante , Perforación Intestinal/etiología , Perforación Intestinal/diagnóstico por imagen , Insuficiencia Multiorgánica/etiología , Resultado Fatal , Peritonitis/etiología , Masculino , Enema Opaco/efectos adversos , Enema Opaco/métodos , Sulfato de Bario/efectos adversos , Medios de Contraste/efectos adversosRESUMEN
OBJECTIVES: To evaluate the influence of collateral vascularization on surgical cleft palate closure and deformities. MATERIALS AND METHODS: Corrosion casting was performed using red-colored acrylic resin in twelve fresh adult cadavers with a normal hard palate. Additionally, white-colored barium sulfate was injected into a fetus with a unilateral complete cleft palate, and layer-by-layer tissue dissection was performed. Both substances were injected into the external carotid arteries. Corrosion casting involved dissolving the soft and hard tissues of the orofacial area utilizing an enzymatic solution. RESULTS: In normal palates, bilateral intraosseous infraorbital arteries formed a network in the premaxilla with the intraosseous nasopalatine- and greater palatine arteries (GPAs). The perforating GPAs anastomosed with the sphenopalatine artery sub-branches. Bilateral extraosseous GPA anastomoses penetrated the median palatine suture. Complex vascularization in the retrotuberal area was detected. In the cleft zone, anastomoses were omitted, whereas in the non-cleft zone, enlarged GPAs were distributed along the cleft edges and followed the anatomical course anteriorly to initiate the network with facial artery sub-branches. CONCLUSIONS: The anatomical subunits of the palate exhibited distinct anastomosis patterns. Despite omitted anastomoses with collateral circulation in the cleft zone, arteries maintained their anatomical pattern as seen in the normal specimen in the non-cleft zone. CLINICAL RELEVANCE: Based on the findings in normal- and cleft palates, surgeons may expect developed anastomosis patterns in the non-cleft zone. Due to the lack of microcirculation in the cleft zone, the existent anastomoses should be maintained as much as possible by the surgical technique. This applies anteriorly in the incisive canal territory, alveolar ridges, and posteriorly in the retrotuberal area.
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Cadáver , Fisura del Paladar , Circulación Colateral , Molde por Corrosión , Paladar Duro , Humanos , Fisura del Paladar/cirugía , Circulación Colateral/fisiología , Paladar Duro/irrigación sanguínea , Femenino , Masculino , Sulfato de Bario , Adulto , Feto/irrigación sanguíneaRESUMEN
BACKGROUND: People recurrently have difficulties swallowing solid medications, which can be associated with the size of the medication and the age and gender of individuals. OBJECTIVE: To evaluate the impact of capsule size and adults' age and gender on oral and pharyngeal capsule transit during capsule swallows. METHODS: Videofluoroscopy was used to measure capsule oral and pharyngeal transit during swallows in 49 healthy individuals (17 men and 32 women), with a mean age of 46 years (ranging from 23 to 88 years). Smaller capsules were filled with 0.50 mL of barium sulfate, and larger capsules were filled with 0.95 mL of barium sulfate; the volume of liquid ingested with the capsules was also quantified in each ingestion. The measurements included the oral preparation time, oral transit time, swallowing reaction time, time to laryngeal vestibule closure, laryngeal vestibule closure duration, pharyngeal transit time, and upper esophageal sphincter opening duration. RESULTS: The capsule size did not influence either the oral or pharyngeal transit time. Increased liquid volume was ingested with larger capsules and by people older than 40 years. The oral transit time was shorter in older adults (60-88 years), and the time to laryngeal vestibule closure was longer in women. CONCLUSION: The size of large capsules did not make a difference in oral or pharyngeal transit when compared with smaller capsules. The capsule size and the participant's age influenced the volume of liquid ingested - larger capsules and older individuals required a larger volume. The capsule oral transit was faster in individuals older than 60 years. BACKGROUND: â¢Swallowing is influenced by the characteristics of what is being swallowed. BACKGROUND: â¢There was no difference in swallowing capsules containing 0.50 mL or 0.95 mL. BACKGROUND: â¢Larger capsules need more liquid ingestion to make swallowing easier. BACKGROUND: â¢Individuals older than 40 years need a greater volume of liquid to swallow capsules than younger adults.
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Trastornos de Deglución , Laringe , Masculino , Humanos , Femenino , Anciano , Persona de Mediana Edad , Deglución , Sulfato de Bario , Trastornos de Deglución/diagnóstico por imagen , Faringe/diagnóstico por imagen , FluoroscopíaRESUMEN
High-density waste drilling fluid contains an abundance of recyclable weighting reagents, direct disposal can pollute the environment. In this paper, the primary mineral composition of a high-density waste drilling fluid from a well in the southwest oil and gas field was analyzed. This paper proposes ß-cyclodextrin (ß-CD) as a depressant for the recovery of barite from waste drilling fluid. The recovery process was investigated through inverse flotation experiments, and the mechanism was analyzed using zeta potential, contact angle analysis, and FTIR. The flotation experiments showed that under the SDS flotation system, when the pH was 9.0 and the amount of depressant ß-CD was 900 g/t, the barite recovery and density reached the highest values, which were 87.41% and 4.042 g/cm3, respectively. Zeta potential experiments, contact angle analysis, and FTIR analysis indicate that ß-CD adsorbed onto barite through enhancing the hydrophilicity of barite, electrostatic force adsorption, and strong adsorption, which could not be displayed by SDS through competitive adsorption. Furthermore, ß-CD exhibited a selective inhibitory effect on barite and enabled reverse flotation. The mechanism model of the flotation separation process was established.
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Sulfato de Bario , AdsorciónRESUMEN
INTRODUCTION: Bronchoalveolar lavage (BAL) is frequently used in pulmonary medicine though it requires further optimization. Practical obstacles such as patient safety and procedural limitation have to date precluded large, controlled trials aimed at standardization of BAL procedure. Indeed, BAL guidelines are based on observational data. Innovative research methods are necessary to advance the clinical practice of BAL. METHODS: In our study, we evaluated the effect of injecting a gelatinized barium solution into different lobes and segments of cadaveric lungs. As the technique requires an irreversible injection into lung airspaces, it is not suitable for in vivo purposes. We measured the volume returned from BAL as well as the distribution of BAL injection via dissection. Segmental anatomic orientation was compared to a radiologist's impression of plain film radiographs taken of injected lungs. RESULTS: Mean injected volume distributions were greatest in the upper lobes and lowest in the lower lobes; mean ratios of injected volume distribution to lung lobe volume also followed this trend. Cannulated bronchi orders favored lower branches in the upper lobe and higher branches in the lower lobes. Segmental anatomy varied by the lung lobe injected and was most varied in the lower lobes. CONCLUSION: This novel gelatinized-barium injection technique provides a minimally complex method to yield clinically meaningful feedback on the performance of BAL. The technique is also adaptable to study of procedural parameters in the context of variable lung anatomies and pathologies.
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Sulfato de Bario , Pulmón , Humanos , Bario , Lavado Broncoalveolar , Pulmón/diagnóstico por imagen , Bronquios , Líquido del Lavado Bronquioalveolar , Broncoscopía/métodosRESUMEN
BACKGROUND AND AIMS: Efforts have been made to develop an endoscopic screening system incorporating serologic gastric cancer (GC) risk stratification (ABC classification) alongside annual population-based GC screening using barium. We conducted a randomized controlled trial (RCT) to compare GC detection rates between the Ba-Endo group, which underwent annual barium tests for primary screening followed by detailed endoscopic examinations, and the ABC-Endo group, where endoscopy intervals were determined based on individual gastric cancer risk in the ABC classification. METHODS: In total, 1206 individuals from Yurihonjo and Nikaho City, Akita Prefecture, were randomized through the minimization method using sex and age as allocation factors. The intervention study was conducted for both groups over 5 years. The Ba-Endo group received annual barium tests, and the ABC-Endo group underwent EGD at different intervals: group A, EGD only at entry; group B, EGD once every 3 years; group C, EGD once every 2 years; and group D, EGD every year. RESULTS: There were 24 detected GC lesions, with a GC detection rate of 1.9%. GC detection rates in the Ba-Endo and ABC-Endo groups were 2.0% and 1.8%, respectively, with no significant differences between groups (P = 1.0). However, the rate of GC cured by endoscopic resection alone was 41.6% in the Ba-Endo group and was significantly higher at 90.9% in the ABC-Endo group (P = .02). CONCLUSIONS: There were no differences between the Ba-Endo and ABC-Endo groups in GC detection rates. However, the rate of detected GCs that could be cured by endoscopic resection alone was significantly higher in the ABC-Endo group. (Clinical trial registration number: UMIN000005962.).
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Detección Precoz del Cáncer , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Anciano , Detección Precoz del Cáncer/métodos , Medición de Riesgo , Gastroscopía/métodos , Sulfato de Bario , Medios de Contraste , Endoscopía Gastrointestinal/métodosRESUMEN
Modified Barium Swallow Studies (MBSS) are a critical part of the evaluation, treatment planning, and outcome assessment for persons with swallowing disorders. Since MBSSs use ionizing radiation with associated cancer risks, many clinicians have reduced radiation exposure by reducing the fluoroscopic pulse rate. However, by reducing pulse rate, we also decrease the temporal resolution of MBSSs which has been shown in pilot studies to significantly reduce diagnostic accuracy. Two hundred MBSSs from patients routinely undergoing MBSS as standard of care conducted at 30 pulses per second (pps) using the Modified Barium Swallow Study Impairment Profile (MBSImP™) standardized administration protocol were selected. A stratified sampling method ensured that a full range of swallowing impairments (etiology, type, and severity) was represented. Recordings were down sampled from 30 pps to 15, 7.5, and 4 pps. MBSSs were rated using the MBSImP components and Penetration-Aspiration Scale (PAS) score for each swallow. Percent agreement was calculated across raters for MBSImP and PAS scores by bolus type and volume. The Least-Squares Method was used for hypothesis testing. Statistically significant and clinically meaningful changes in scores of swallowing physiology and penetration/aspiration occurred when reducing pulse rate below 30pps. These changes were evident across bolus types and volumes. Given the impact on diagnostic accuracy and the low radiation risks to adults undergoing MBSSs, reducing pulse rate to 15pps or below is not aligned with the As Low As Reasonably Achievable (ALARA) principle and should not be used as a viable method to reduce radiation exposure from MBSSs.
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Trastornos de Deglución , Deglución , Humanos , Fluoroscopía/métodos , Trastornos de Deglución/fisiopatología , Trastornos de Deglución/diagnóstico , Deglución/fisiología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Sulfato de Bario/administración & dosificación , Medios de Contraste/administración & dosificación , Exposición a la Radiación/prevención & control , Anciano de 80 o más AñosRESUMEN
Ester-based drilling fluids (EBDF) are preferred over oil-based drilling fluids (OBDF) and water-based drilling fluids (WBDF) because of their great biodegradability, low toxicity, and improved performance. In this work, waste cooking oil methyl ester (WCOME) was used to prepare an environmentally friendly EBDF. Through a transesterification process utilizing a modified calcium oxide based heterogenous catalyst, the waste cooking oil is transformed into waste cooking oil methyl ester. Response surface approach was used to strengthen the transesterification. The optimize conditions for CaO/Al2O3 resulted in the highest yield of 96.56% at a molar ratio of 11.9:1, 3.19 wt % of CaO/Al2O3, 53.79 °C, and 76.86 min. In contrast, CaO/TiO2 yielded 98.15% at a molar ratio of 11.99:1, with a CaO/TiO2 of 2.53 wt % at 59.79 in 68.14 min. Additionally, two separate densities of 9 ppg and 12 ppg EBDF are formulated with two distinct oil-to-water ratios (70:30 and 80:20) using synthesized WCOME. To assess the effectiveness of formulated EBDF thorough rheological investigation is conducted at 150°. Additionally, the filtration loss at HPHT conditions, emulsion stability, and Barite sag analysis of the drilling fluid are all analyzed at before ageing and after dynamic ageing. With better rheological features, less fluid loss, good emulsion stability, and minimal barite sagging, the designed EBDF performs efficiently. The drilling fluid met the API requirement and demonstrated stability even after ageing at 250 °F for 72 h, suggesting that it may be used for extended periods of time in drilling.
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Sulfato de Bario , Aceites de Plantas , Emulsiones , Ésteres , Agua , CulinariaRESUMEN
BACKGROUND: With increasing incidence of esophageal cancer, a growing number of patients are at risk of developing delayed gastric conduit emptying (DGCE) in the early postoperative phase after esophagectomy. This condition is of great postoperative concern due to its association with adverse outcomes. PURPOSE: To give a narrative review of the literature concerning radiological diagnosis of DGCE after esophagectomy and a proposal for an improved, functional protocol with objective measurements. MATERIAL AND METHODS: The protocol was designed at Virginia Mason Medical Center in Seattle and is based on the Timed Barium Esophagogram (TBE) concept, which has been adapted to assess the passage of contrast from the gastric conduit into the duodenum. RESULTS: The literature review showed a general lack of standardization and scientific evidence behind the use of radiology to assess DGCE. We found that our proposed standardized upper gastrointestinal (UGI) contrast study considers both the time aspect in DGCE and provides morphologic information of the gastric conduit. This radiological protocol was tested on 112 patients in a trial performed at two high-volume centers for esophageal surgery and included an UGI contrast study 2-3 days postoperatively. The study demonstrated that this UGI contrast study can be included in the standardized clinical pathway after esophagectomy. CONCLUSION: This new, proposed UGI contrast study has the potential to diagnose early postoperative DGCE in a standardized manner and to improve overall patient outcomes after esophagectomy.
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Medios de Contraste , Esofagectomía , Complicaciones Posoperatorias , Humanos , Esofagectomía/métodos , Complicaciones Posoperatorias/diagnóstico por imagen , Femenino , Masculino , Vaciamiento Gástrico , Persona de Mediana Edad , Anciano , Neoplasias Esofágicas/cirugía , Neoplasias Esofágicas/diagnóstico por imagen , Sulfato de BarioRESUMEN
Barium sulfate and iohexol are commonly used as contrast agents for videofluoroscopic swallowing study (VFSS). This study compared their usefulness as contrast agents in visualizing components of swallowing predictable of subsequent pneumonia and unintentional weight loss after VFSS. This was a randomized, controlled, crossover trial. The two contrast agents were alternately used in the same participants, and the order in which the contrast agent was tested first was randomly assigned. After VFSS, we followed the participants for 3 months and the association between VFSS findings of each contrast agent and the subsequent pneumonia and unintentional weight loss were analyzed. A total of 30 participants were included in the analysis. We recorded 11 cases of subsequent pneumonia and 13 of unintentional weight loss. Regarding the risk of subsequent pneumonia after VFSS, only the oral transit time and number of swallows tested with barium sulfate indicated significant differences between participants with and without subsequent pneumonia. For unintentional weight loss, oral transit time and pharyngeal wall coating after swallowing tested with barium sulfate, as well as oral transit time, nasal penetration, residue in the valleculae, PAS scores, and number of swallows when testing with iohexol demonstrated significant differences between those with and without unintentional weight loss.
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Trastornos de Deglución , Neumonía , Humanos , Sulfato de Bario , Medios de Contraste , Deglución , Trastornos de Deglución/diagnóstico por imagen , Fluoroscopía , Yohexol , Grabación en Video , Pérdida de Peso , Estudios CruzadosRESUMEN
Barite ore is typically associated with difficult-to-remove vein minerals, but commercial barite products require a high BaSO4 content. We investigated the occurrence state of fluoride in barite ore using various analytical techniques, which indicated that elemental fluorine in barite predominantly exists as fluorite. Fluoride was then leached from barite ore via complexation. The effects of HCl and AlCl3 concentrations, temperature, time, and liquid-solid ratio on the leaching rate were examined, and the leaching conditions were optimized using an orthogonal array method. The fluorine leaching rate approached 93.11% after stirring for 30 min at 90 °C and 300 rpm with 3 mol/L HCl, 0.4 mol/L AlCl3, a liquid-solid ratio of 10:1 mL/g, and an ore sample size of -75 µm + 48 µm. According to the leaching kinetics, the process conformed to the solid membrane diffusion control model at a high temperature and the joint chemical reaction-diffusion control model at a low temperature. The apparent activation energy was 56.88 kJ/mol. Furthermore, aluminum and fluorine coordination numbers increased with increasing Al3+/F- molar concentration ratios. Competing complexation reactions of Al3+, H+, and F- occurred at three levels. This complexation approach effectively leaches fluoride from barite, improves barite product quality, and reduces environmental pollution.
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Sulfato de Bario , Fluoruros , Flúor , Aluminio , MineralesRESUMEN
Naturally occurring radioactive materials (NORMs) can be found in decommissioned oil and gas infrastructure (e.g. pipelines), including scales. The effects of NORM contaminants from offshore infrastructure on benthic macroorganisms remain poorly understood. To test the potential ecological effects of NORM-contaminated scale, we exposed a marine amphipod, a clam and a polychaete to marine sediments spiked with low level concentrations of barium sulfate scale retrieved from a decommissioned subsea pipe. Only amphipods were included in further analysis due to treatment mortalities of the clam and polychaete. Barium (Ba) and copper (Cu) were elevated in the seawater overlying the spiked sediments, although no sediment metals exceeded guidelines. 210Po was the only NORM detected in the overlying waters while both 210Po and 226Ra were significantly elevated in the scale-contaminated sediments when compared with the control sediments. The whole-body burden of Ba and 226Ra were significantly higher in the scale-exposed amphipods. Using experiment- and scale-specific parameters in biota dose assessments suggested potential dose rates may elicit individual and population level effects. Future work is needed to assess the biological impacts and effects of NORM scale at elevated levels above background concentrations and the accumulation of NORM-associated contaminants by marine organisms.
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Anfípodos , Productos Biológicos , Animales , Bario , Sulfato de BarioRESUMEN
Barite (BaSO4) precipitation is one of the most ubiquitous examples of secondary sulfate mineral scaling in shale oil and gas reservoirs. Often, a suite of chemical additives is used during fracturing operations to inhibit the accumulation of mineral scales, though their efficacy is widely varied and poorly understood. This study combines experimental data and multi-component numerical reactive transport modeling to offer a more comprehensive understanding of the geochemical behavior of barite accumulation in shale matrices under conditions typical of fracturing operations. A variety of additives and conditions are individually tested in batch reactor experiments to identify the factors controlling barite precipitation. Our experimental results demonstrate a pH dependence in the rate of barite precipitation, which we use to develop a predictive model including a pH-dependent term that satisfactorily reproduces our observations. This model is then extended to consider the behavior of three major shale samples of highly variable mineralogy (Eagle Ford, Marcellus, and Barnett). This data-validated model offers a reliable tool to predict and ultimately mitigate against secondary mineral accumulation in unconventional shale reservoirs.
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Sulfato de Bario , Yacimiento de Petróleo y Gas , Sulfatos , MineralesRESUMEN
BACKGROUND: Esophageal morphology in achalasia is thought to affect outcomes, with "end-stage" sigmoidal morphology faring poorly; however, evaluation of morphology's role in outcomes has been limited by lack of objective characterization. Hence, the goals of this study were twofold: characterize the variability of timed barium esophagram (TBE) interpretation and evaluate an objective classification of TBE tortuosity: length-to-height ratio (LHR). We hypothesized that the esophagus must elongate to become sigmoidal such that sigmoidal morphology would demonstrate a larger LHR. METHODS: Ninety pre-operative TBEs were selected from an institutional database. Esophageal morphology was categorized as straight, intermediate, or sigmoidal. Esophageal length was measured by a mid-lumen line from the aortic knob to the esophagogastric junction on TBE; height was measured vertically from the aortic knob to the level of the esophagogastric junction. The length divided by the height generated the LHR. Descriptive statistics and frequency of expert agreement were calculated. Median LHR was compared between consensus morphologies. A receiver operating characteristic (ROC) determined the optimal LHR for sigmoidal vs non-sigmoidal characterization. RESULTS: From a total of 90 pre-operative TBEs, expert consensus morphology was reached in 56 (62.2%) cases. Pairs of experts agreed on morphology in 62-74% of TBEs, with all three experts agreeing on 46.7-48.9% of cases. Median LHR between expert consensus morphologies was 1.03, 1.09, and 1.24 for straight, intermediate, and sigmoidal morphologies, respectively (p < 0.001). ROC demonstrated that an LHR cutoff of 1.13 was 100% sensitive and 95% specific (AUC 0.99) for ruling out sigmoidal morphology. CONCLUSION: These findings confirm our anecdotal experience that subjective morphology interpretation is variable, even between experts at a high-volume center. LHR provides an objective method for classification, allowing us to overcome the limitations of inter-observer variability, thus paving the way for future study of the role of morphology in achalasia outcomes.
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Acalasia del Esófago , Humanos , Acalasia del Esófago/diagnóstico por imagen , Acalasia del Esófago/cirugía , Sulfato de Bario , Manometría/métodos , Unión EsofagogástricaRESUMEN
The colloidal transport of trace (Fe, Al, Ba, Pb, Sr, U) and ultra-trace (226Ra) elements was studied in a mining environment. An original approach combining 0.45 µm filtered water sampling, the Diffusive Gradient in Thin films (DGT) technique, mineralogical characterization, and geochemical modelling was developed and tested at 17 sampling points. DGT was used for the truly dissolved fraction of the elements of interest, while the 0.45 µm filtration includes both colloidal and truly dissolved fractions (together referred to as total dissolved fraction). Results indicated a colloidal fraction for Al (up to 50%), Ba (up to 86%), and Fe (up to 99%) explained by the presence of submicrometric grains of kaolinite, barite, and ferrihydrite, respectively. Furthermore, the total dissolved 226Ra concentration in the water samples reached up to 10-25 Bq/L (1.2-3.0 10-12 mol/L) at 3 sampling points, while the truly dissolved aqueous 226Ra concentrations were in the mBq/L range. Such high total dissolved concentrations are explained by retention on colloidal barite, accounting for 95% of the total dissolved 226Ra concentration. The distribution of 226Ra between the truly dissolved and colloidal fractions was accurately reproduced using a (Rax,Ba1-x)SO4 solid solution, with values of the Guggenheim parameter a0 close to ideality. 226Ra sorption on ferrihydrite and kaolinite, other minerals well known for their retention properties, could not explain the measured colloidal fractions despite their predominance. This illustrates the key role of barite in such environments. The measured concentrations of total dissolved U were very low at all the sampling points (<4.5 10-10 mol/L) and the colloidal fraction of U accounted for less than 65%. U sorption on ferrihydrite could account for the colloidal fraction. This original approach can be applied to other trace and ultra-trace elements to complement when necessary classical environmental surveys usually performed by filtration on 0.45 µm.