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The automatic generation of descriptions for medical images has sparked increasing interest in the healthcare field due to its potential to assist professionals in the interpretation and analysis of clinical exams. This study explores the development and evaluation of a generalist generative model for medical images. Gaps were identified in the literature, such as the lack of studies that explore the performance of specific models for medical description generation and the need for objective evaluation of the quality of generated descriptions. Additionally, there is a lack of model generalization to different image modalities and medical conditions. To address these issues, a methodological strategy was adopted, combining natural language processing and features extraction from medical images and feeding them into a generative model based on neural networks. The goal was to achieve model generalization across various image modalities and medical conditions. The results showed promising outcomes in the generation of descriptions, with an accuracy of 0.7628 and a BLEU-1 score of 0.5387. However, the quality of the generated descriptions may still be limited, exhibiting semantic errors or lacking relevant details. These limitations could be attributed to the availability and representativeness of the data, as well as the techniques used.

Molecular dynamics simulations were used to investigate the initial stage of phase separation mechanisms for an oversaturated electrolytic solution. We developed a low computational cost methodology to determine the simulation frames where the first ionic clusters are formed. By discretizing the simulation box, we obtain a density profile in the moments preceding and succeeding the nuclei's formation. The growth of the clusters identified with our methodology was analyzed until the end of the simulation. Calculation of the Steinhardt parameter showed symmetry of the solid, giving indications that the classical nucleation theory explains the mechanism of the solid formation. The methodology developed was useful for identifying phase separation mechanisms in the nucleation process. At lower concentrations, there was no formation of stable clusters. At intermediate concentrations, the analyses indicate a transition of phases in one stage, from a oversaturate electrolytic solution to a crystalline solid. At high concentration, a transition of phases in two stages, initially, is the formation of a dense liquid, and only after that, crystalline solid formed inside the dense liquid. The change in phase separation mechanism due to increasing oversaturation underscores the importance of precise determination of the driving force for phase separation and concentration limits for each mechanism., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The interest in the simulated moving bed (SMB) technology lies in its variants. Some of them that have a high potential to increase the performance in enantioseparations are the ModiCon and the ModiCon+VariCol. These variants are based on the modulation of feed concentration and a combination of feed concentration and length of zones modulations. The concept of the ModiCon process in the literature is that it can be applied only for systems described by nonlinear isotherms. However, there are no numerical or experimental studies that prove that. On the other hand, the hybrid operation of ModiCon+VariCol can be used in systems with a low number of columns due to the flexibility in the use of columns, but it has been little explored. In this work, the maximal performance of the ModiCon process was compared with the SMB process for a linear isotherm. Additionally, the ModiCon+VariCol process was evaluated in systems with a low number of columns. The enantioseparation of guaifenesin was considered as a case study. The result shows that the ModiCon process can also be applied with high performance in systems described by linear isotherms. In the evaluation of the ModiCon+VariCol process for unequal product purity, it was found that the hybrid operation with 3 columns showed a higher throughput and productivity than the SMB process with 6 columns. The productivity of the ModiCon+VariCol was more than three times higher than the conventional operation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The VariCol and ModiCon processes are two variants of the simulated moving bed (SMB) process, characterized by the modulation of the length of zones of the chromatographic column train and the feed concentration. These features give more flexibility than the conventional operation, leading to essential improvements in the separation and purification of mixtures. The optimal performance comparison of these two variants, the hybrid formed by their combination, and the conventional SMB process are scarce in the literature. This comparison helps discover new characteristics of each single and combined operation mode and creates guidelines to select the appropriate operation mode for possible real applications. In this work, the performance comparison of the ModiCon, VariCol, ModiCon+VariCol, and SMB processes is carried out in terms of maximal throughput for specific product purity values. Particular emphasis is placed on both the ModiCon and the hybrid ModiCon+VariCol processes characteristics. A strategy for combining and optimizing the ModiCon and the VariCol processes was determined. As a case study, the enantioseparation of guaifenesin was considered. In the ModiCon process, more than two modulation subintervals did not improve the performance in the separation. The optimal pattern, based on two subintervals, has zero feed concentration in the first subinterval and the maximal concentration in the second one. The best result for the hybrid operation (ModiCon+VariCol) was reached when the feed port moves simultaneously as the SMB process switching period. The optimal throughput of the ModiCon and the ModiCon+VariCol processes was almost doubled than that of the SMB process. These performances were based on larger zones I and II and not in zones II and III as occur with the SMB and VariCol process. The throughput in the hybrid operation increases more significantly than the ModiCon process when 5 columns were considered instead of 6. The hybrid operation could be more attractive for a system with a few numbers of columns., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The VariCol process is a variant of the conventional simulated moving bed (SMB) process, distinguished by the asynchronous shifting of the inlet and outlet ports of the chromatographic column train. This feature allows for a more flexible operation in column utilization and can also achieve higher separation performances. However, to take full benefit out of it, the operating parameters, such as the strategy for port switching, must be optimal. in this paper, a novel methodology for optimizing those parameters, based on a single NLP (non-linear programming), is proposed. The main advantage of this approach is that it significantly reduces the complexity of the original MINLP (mixed-integer non-linear programming) formulation currently discussed in the literature. The proposed optimization problem is built, considering that the average column configuration of three zones provides the necessary and sufficient information to describe the VariCol process. Several optimization scenarios for the enantioseparation of 1,1´-bi-2-naphthol and aminoglutethimide were considered to evaluate the proposed methodology and to compare the performance of VariCol and SMB processes. The results have shown that with the single NLP approach, it is possible to explore the optimal solution in all the VariCol process domains with less computational effort than other optimization strategies reported in the literature. That is a great advantage, especially in the context of real-time applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Beer-Lambert-Bouguer law is for a limiting case and, therefore, it is not useful to describe the relationship between absorption signal and enantiomer concentration in a stream when there are nonlinear phenomena present. In this work, the Chiral Detector (CD-2095 JASCO) equipment was used to measure simultaneously the UV-Vis and circular dichroism (CD) signals of a stream with different compositions of praziquantel enantiomers. The tested models were calibrated (parameter estimation) and validated using the Leave-One-Out Cross Validation (LOOCV) method. Both UV-vis and CD signals were absorbed differently in mixtures in comparison to pure solutions, indicating a nonlinear relationship between the absorbed signal and the enantiomer concentration in a mixture stream. Empirical mathematical relationships were tested for each signal (UV-vis and CD) and the pair of equations was evaluated using the Mean Square Error (MSE) metric for each enantiomer concentration (MSE L and MSE D ) and the pair of equations with the smallest MSE t (=MSE L  + MSE D ) metric was chosen. Confidence interval analysis helped to find even simpler equations in comparison to the chosen ones. Higher nonlinearity was observed for a mixture with low L-PZQ concentration. The developed methodology allowed the choice of an empiric model to give good predictions in a wide range of concentration, what is of utmost importance for monitoring and automatic control purposes, for instance., Competing Interests: Declaration of competing interest X The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Praziquantel (PZQ) composes a regular medicine available in a tablet form to fight schistosomiasis and just half of its mass is composed by the active principle (L-PZQ), the other half, D-PZQ, is frequently associated to a strong bitter taste. Moreover, optically pure L-PZQ derivatives could be used in studies about adult and juvenile worms' resistance. Nowadays, these studies use racemic PZQ (rac-PZQ) as starting point. The D-PZQ, which would be discarded, could be racemized, coming back as feed concentration in the process. The present work aims to get L-PZQ and D-PZQ with high optical purities (more than 97%) and productivity (more than 253 g kg ads -1  day -1 ) towards semipreparative scale for researches involving L-PZQ, L-PZQ derivatives, and D-PZQ racemization. In order to achieve this goal, a built-in-house simulated moving bed chromatographic unit with the cellulose tris (3-chloro-4-methylphenylcarbamate) (Chiralcel OZ) as chiral stationary phase (CSP) was used to investigate different scenarios of separation according to a well-known design method called triangle theory. In all scenarios investigated, at least one of the outlet streams presented high optically purity for one of the enantiomers. Comparison with literature showed superior performance of our unit even at racemic mixture concentrations that were 10 times lower than the racemic concentrations found in literature., (© 2019 Wiley Periodicals, Inc.)

An adaptive nonlinear model predictive control of a simulated moving bed unit for the enantioseparation of praziquantel is presented. A first principle model was applied at the proposed purity control scheme. The main concern about this kind of model in a control framework is in regard to the computational effort to solve it; however, a fast enough solution was achieved. In order to evaluate the controller's performance, several cases were simulated, including external pumps and switching valve malfunctions. The problem of plant-model mismatch was also investigated, and for that reason a parameter estimation step was introduced in the control strategy. In every studied scenario, the controller was able to maintain the purity levels at their set points, which were set to 99% and 98.6% for extract and raffinate, respectively. Additionally, fast responses and smooth actuation were achieved., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Introduction: The aim of this study is to evaluate the risk factors for acute kidney injury (AKI) and 30-day mortality after liver transplantation., Material and Methods: This is a retrospective cohort of consecutive adults undergoing orthotopic liver transplantation (OLT) at a referral hospital in Brazil, from January 2013 to January 2014. Risk factors for AKI and death were investigated., Results: A total 134 patients were included, with median age of 56 years. AKI was found in 46.7% of patients in the first 72 h after OLT. Risk factors for AKI were: viral hepatitis (OR 2.9, 95% CI = 1.2-7), warm ischemia time (OR 1.1, 95% CI = 1.01-1.2) and serum lactate (OR 1.3, 95%CI = 1.02-1.89). The length of intensive care unit (ICU) stay was longer in AKI group: 4 (3-7) days vs. 3 (2-4) days (p = 0.001), as well as overall hospitalization stay: 16 (9-26) days vs. 10 (8- 14) days (p = 0.001). The 30-day mortality was 15%. AKI was an independent risk factor for mortality (OR 4.3, 95% CI = 1.3-14.6). MELD-Na ≥ 22 was a predictor for hemodialysis need (OR 8.4, 95%CI = 1.5-46.5). Chronic kidney disease (CKD) was found in 36 patients (56.2% of AKI patients)., Conclusions: Viral hepatitis, longer warm ischemia time and high levels of serum lactate are risk factors for AKI after OLT. AKI is a risk factor for death and can lead to CKD in a high percentage of patients after OLT. A high MELD-Na score is a predictor for hemodialysis need.

Introduction: Pharynx is a muscular organ with is sustained by craniofacial bones. It is divided into nasal, oral and hipopharynx, and can be considered as a tube that serves both respiratory and digestive systems. Its anatomical morphology permits that factors facilitate its obstruction, leading to the sleep apnea syndrome. One of the treatment consists of surgical mandibular advancement, increasing pharyngeal dimensions. The aim of this study was evaluate the cephalometric changes in the pharyngeal airway space after orthognathic surgery procedures for correction of mandibular prognathism., Materials and Methods: Pre and post-operative cephalometric analysis was performed on 19 patients submitted to mandibular setback by mandibular bilateral sagittal split osteotomy associated with maxillary advancement by Le Fort I osteotomy, using the Dolphin Imaging 10.0 software., Results: Results did not reveal statistically significant changes in the upper (nasopharyngeal), middle (oropharyngeal) and lower (hypopharyngeal) airway spaces, but showed increase in the nasal pharynx due the maxillary advancement and a lower position of the hyoid bone due the mandibular setback., Discussion: Maxillomandibular orthognathic surgery for correction of mandibular prognathism does not seem to statistically significantly change the pharyngeal airway space, but it increases the maxillary airway., Conclusion: It seems to be important to consider the double jaw surgery in cases of mandibular prognathism, aiming prevention of a possible reduction of whole upper airway.

Objective: To examine the factors associated with acute kidney injury and outcome in patients with lung disease., Methods: A prospective study was conducted with 100 consecutive patients admitted to a respiratory intensive care unit in Fortaleza (CE), Brazil. The risk factors for acute kidney injury and mortality were investigated in a group of patients with lung diseases., Results: The mean age of the study population was 57 years, and 50% were male. The incidence of acute kidney injury was higher in patients with PaO2/FiO2<200 mmHg (54% versus 23.7%; p=0.02). Death was observed in 40 cases and the rate of mortality of the acute kidney injury group was higher (62.8% versus 27.6%; p=0.01). The independent factor that was found to be associated with acute kidney injury was PaO2/FiO2<200 mmHg (p=0.01), and the independent risk factors for death were PEEP at admission (OR: 3.6; 95%CI: 1.3-9.6; p=0.009) and need for hemodialysis (OR: 7.9; 95%CI: 2.2-28.3; p=0.001)., Conclusion: There was a higher mortality rate in the acute kidney injury group. Increased mortality was associated with mechanical ventilation, high PEEP, urea and need for dialysis. Further studies must be performed to better establish the relationship between kidney and lung injury and its impact on patient outcome.

Background: Paranasal sinus osteomas are rare benign tumors. Although various theories such as trauma and infection have been proposed, it is difficult to establish the pathogenesis of osteoma. Osteomas may be detected with routine radiographic examination or the tumors may enlarge and cause symptoms. Osteomas most frequently occur in the frontal and ethmoid sinuses, and are rare in the maxillary sinus., Case Report: In the present study, we report a case of an 18-year-old woman with a maxillary sinus osteoma. Radiographically, the tumor was characterized as a radiopaque, well-delimited lesion in the periapical region of teeth 27 and 28 that had positive sensitivity test. After computed tomographic scanning and complete removal of the tumor, the histopathological diagnosis was osteoma. After 1 year of follow-up, the patient shows no signs of recurrence.

The aim of this study is to investigate the changes in clinical pattern and therapeutic measures in leptospirosis-associated acute kidney injury; a retrospective study with 318 patients in Brazil. Patients were divided according to the time of admission: 1985-1996 (group I) and 1997-2010 (group II). Patients were younger in group I (36 ± 13 versus 41 ± 16 years, P = 0.005) and the numbers of oliguria increased (21% versus 41% in group II, P = 0.014). Higher frequency of lung manifestations was observed in group II (P < 0.0001). Although increased severity, there was a significant reduction in mortality (20% in group I versus 12% in group II, P = 0.03). Mortality was associated with advanced age, low diastolic blood pressure, oliguria, arrhythmia, and peritoneal dialysis, besides a trend to better mortality with penicillin administration. Leptospirosis is occurring in an older population, with a higher number of oliguria and lung manifestations. However, mortality is decreasing and can be the result of changes in treatment.

Aim: Acute kidney injury (AKI) is a common complication in leptospirosis. The aim of this study is to investigate the association between RIFLE and AKIN classifications with mortality in leptospirosis-associated AKI., Methods: A retrospective study was conducted in patients with leptospirosis admitted to tertiary hospitals in Brazil. The association between RIFLE and AKIN classifications with mortality was investigated. Univariate and multivariate analysis was performed to investigate risk factors for death., Results: A total of 287 patients were included, with an average age of 37 ± 16 years, and 80.8% were male. Overall mortality was 13%. There was a significant association between these classifications and death. Among non-survivors, 86% were in the class 'failure' and AKIN 3. Increased mortality was observed according to the worse classifications: 'risk' (R; 2%), 'injury' (I; 8%) and 'failure' (F; 23%), as well as in AKIN 1 (2%), AKIN 2 (8%) and AKIN 3 (23%) (P < 0.0001). The worst classifications were significantly associated with death: RIFLE F (odds ratio = 11.6, P = 0.018) and AKIN 3 (odds ratio = 12.8, P = 0.013). Receiver-operator curve for patients with AKI showed high areas under the curve (0.71, 95% confidence interval = 0.67-0.74) for both RIFLE and AKIN classifications in determining the sensitivity for mortality., Conclusion: There is a significant association between RIFLE and AKIN classifications with mortality in patients with leptospirosis. Initiation of dialysis in patients with RIFLE F and AKIN 3 should always be considered., (© 2011 The Authors. Nephrology © 2011 Asian Pacific Society of Nephrology.)

Background: Acute kidney injury (AKI) is a frequent complication in hospitalized patients, especially in those in intensive care units (ICU). The RIFLE classification might be a valid prognostic factor for critically ill cancer patients. The present study aims to evaluate the discriminatory capacity of RIFLE versus other general prognostic scores in predicting hospital mortality in critically ill cancer patients., Methods: This is a single-center study conducted in a cancer-specialized ICU in Brazil. All of the 288 patients hospitalized from May 2006 to June 2008 were included. RIFLE classification, APACHE II, SOFA, and SAPS II scores were calculated and the area under receiver operating characteristic (AROC) curves and logistic multiple regression were performed using hospital mortality as the outcome., Results: AKI, defined by RIFLE criteria, was observed in 156 (54.2%) patients. The distribution of patients with any degree of AKI was: risk, n = 96 (33.3%); injury, n = 30 (10.4%), and failure, n = 30 (10.4%). Mortality was 13.6% for non-AKI patients, 49% for RIFLE 'R' patients, 62.3% for RIFLE 'I' patients, and 86.8% for RIFLE 'F' patients (p = 0.0006). Logistic regression analysis showed that RIFLE criteria, APACHE II, SOFA, and SAPS II were independent factors for mortality in this population. The discrimination of RIFLE was good (AROC 0.801, 95% CI 0.748-0.854) but inferior compared to those of APACHE II (AROC 0.940, 95% CI 0.915-0.966), SOFA (AROC 0.910, 95% CI 0.876-0.943), and SAPS II (AROC 0.869, 95% CI 0.827-0.912)., Conclusion: AKI is a frequent complication in ICU patients with cancer. RIFLE was inferior to commonly used prognostic scores for predicting mortality in this cohort of patients., (Copyright © 2011 S. Karger AG, Basel.)

Background: Acute kidney injury (AKI) is an uncommon but serious complication after trauma. The objective of this study was to evaluate the prevalence, clinical characteristics and outcome of AKI after trauma., Patients and Methods: This was a retrospective study performed from January 2006 to January 2008 in an emergency specialized hospital in Fortaleza city, northeast of Brazil. All patients with AKI admitted in the study period were included. Prevalence of AKI, clinical characteristics and outcome were investigated., Results: Of the 129 patients admitted to the intensive care unit (ICU), 52 had AKI. The mean age was 30.1 ± 19.2 years, and 79.8% were males. The main causes of AKI were sepsis in 27 cases (52%) and hypotension in 18 (34%). Oliguria was observed in 33 cases (63%). Dialysis was required for 19 patients (36.5%). Independent risk factors associated with AKI were abdominal trauma [odds ratio (OR) = 3.66, P = 0.027] and use of furosemide (OR = 4.10, P = 0.026). Patients were classified according to RIFLE criteria as Risk in 12 cases (23%), Injury in 13 (25%), Failure in 24 (46%), Loss in 1 (2%) and End-stage in 2 (4%). Overall in-hospital mortality was 95.3%. The main cause of death was sepsis (24%). Mortality was 100% among patients with AKI., Conclusions: AKI is a fatal complication after trauma, which presented with a high mortality in the studied population. A better comprehension of factors associated with death in trauma-associated AKI is important, and more effective measures of prevention and treatment of AKI in this population are urgently needed.