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In stabilization of a Large-Scale System (LSS), the decentralized nature of the controller is a significant issue, because centralized controllers are difficult and impractical for real-time implementation. The designing procedure for decentralized controllers should guarantee the stability of the overall LSS and at the same time, allow limited information exchange in the LSS. In this paper, a decentralized controller for a nonlinear LSS modeled by a Linear Parameter Varying (LPV) model is designed. The controller design procedure is formulated as a convex feasibility problem which can be solved by finding a feasible answer to some Linear Matrix Inequalities (LMIs). The solution to this feasibility problem assures a fully decentralized controller where information exchange among local controllers is forbidden and, only data transfer among each controller and its corresponding subsystem is allowed. In the proposed approach, the Lyapunov function of the LSS equipped with local controllers is considered as the sum of the Lyapunov functions of all subsystems. Then, the stability conditions are derived to assure the stability of the LSS. After designing a decentralized controller to ensure LSS stability, the same approach is exploited for H∞ and H2 performance improvement of the LSS in the presence of disturbances. To verify the efficacy of the designed controller, a large-scale power system which is a practical example is considered, and the proposed approach is applied on it. The simulation results prove the appropriateness of the designed local controllers.
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This paper aims to design a Model Predictive Control (MPC) law based on the time series data gathered from the input and output of a system. An Auto-Regressive Integrated Moving Average (ARIMA) model with unknown parameters and an unknown sequence of controller signal are considered for the system. Based on a window of data, an optimization problem is formulated which can find the optimal unknown model parameters and controller sequence, simultaneously. This problem is a non-convex optimization problem with many non-convex constraints and difficult to solve. Therefore, a transformation is developed which can transfer the optimization problem to an equivalent problem with convex constraints and a non-convex objective function. This new problem is much easier to solve with the present solvers. The effectiveness of the overall approach is proved via several examples that reveal satisfaction and convincingness.
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Soil moisture (SM) at the interface between the land surface and atmosphere is one of the major environmental parameters which plays an important role in hydrological applications. In this article, the SM measured by Soil Moisture Active Passive (SMAP) is downscaled from 3- to 1-km spatial resolution. The main purpose is to evaluate the performance of two different downscaling methods over a variety of climatic conditions and land cover types. These two methods, based on regression and artificial neural network (ANN), are used for enabling us to cross-validate and reliably interpret the obtained results since the number of ground measurements is not sufficient for accuracy assessment. These methods are applied over four different case studies; one is located in the USA, i.e., state of Utah (semi-arid), and the remaining three are located in Iran, i.e., Fars (arid and semi-arid), Yazd (hyper-arid), and Golestan (humid). In both methods, different combinations of input features correlated with SM including land surface temperature (LST), normalized difference vegetation index (NDVI), brightness temperatures in horizontal and vertical polarizations (TBH and TBV), shortwave infrared (SWIR), and digital elevation model (DEM) are used. It is found that the DEM does not add extra information in downscaling. The reason is due to high correlation between topography and LST. Moreover, SWIR is most likely able to model only large-scale variations of SM. The downscaled SM products are then compared to 1-km resolution SMAP SM extracted from Sentinel-1 for the study areas in Iran and in situ measurements in Utah. Both methods produce results which are considerably consistent except that the regression method adds more spatial details in the downscaled SM. The achievements illustrate that the performance of both downscaling methods is higher in areas with more homogeneous climatic conditions, i.e., Yazd and Golestan. The best evaluation metrics including correlation coefficient (R), root mean square error (RMSE), and mean absolute percentage error (MAPE) for Yazd and Golestan are R = 0.89, RMSE = 0.025 m3/m3, and MAPE = 21.13% and R = 0.93, RMSE = 0.044 m3/m3, and MAPE = 21.95%, respectively. Moreover, large model biases are associated with dense vegetated areas and high altitudes. The best downscaling accuracy in both methods over all study areas belongs to bare soil and flat regions.
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Monitoreo del Ambiente , Tecnología de Sensores Remotos , Atmósfera , Benchmarking , SueloRESUMEN
BACKGROUND: Having moral courage is a crucial characteristic for nurses to handle ethical quandaries, stay true to their professional obligations towards patients, and uphold ethical principles. This concept can be influenced by various factors including personal, professional, organizational, and leadership considerations. The purpose of this study was to explore the predictors of moral courage among nurses working in hospitals. METHODS: In 2018, an observational cross-sectional study was carried out on 267 nurses employed in six hospitals located in the northern region of Iran. The participants were selected through a simple random sampling technique. To collect data, a demographic information form was used along with two questionnaires. The first questionnaire was a standard survey on moral courage, while the second questionnaire was designed to assess the ethical climate. Linear regression was used to assess the predictors of moral courage. RESULTS: Nurses had an average moral courage score of 87.07 ± 15.52 and an average moral climate score of 96.12 ± 17.17. The study showed that 16% of the variation in moral courage scores among nurses was explained by ethical climate and monthly overtime hours. CONCLUSION: This study underscores the significance of establishing an ethical work environment and minimizing overtime hours in order to enhance moral courage among nurses. These findings carry weight for both nursing practice and organizational policies focused on fostering ethical conduct within healthcare settings.
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Coraje , Ética en Enfermería , Humanos , Estudios Transversales , Principios Morales , Encuestas y CuestionariosRESUMEN
Background: Cyclophosphamide (CP) is an anticancer drug that acts as an alkylation agent after metabolism in the liver. CP has toxic effects on the body's cells, especially the reproductive system's function, and causes infertility. Moreover, medicinal plants have few side effects and are psychologically acceptable to patients. Objective: This study aimed to investigate the impact of Ephedra pachyclada hydroalcoholic extract (EPHE) on ovarian tissue and hypothalamic-pituitary-gonadal axis in rats treated with CP. Materials and Methods: In this experimental study, 48 adult female Wistar rats (180-200 gr, 9-10 wk) were randomly assigned to 6 experimental groups (n = 8/each): (a) control; (b) sham; (c) CP; (d) CP+250 mg/kg EPHE; (e) CP+500 mg/kg EPHE; (f) CP+1000 mg/kg EPHE. On the 29th day of the experiment, serum was collected; serum concentration of the luteinizing hormone, follicle-stimulating hormone, estrogen, progesterone, and antioxidant activity were measured. The number of ovarian follicles were also counted. Results: In the CP groups, serum concentrations of follicle-stimulating hormone and luteinizing hormone significantly increased, and estrogen and progesterone significantly decreased (p ≤ 0.05). EPHE significantly compensated for the complications caused by CP and 1000 mg/kg had the greatest effect. Antioxidant reduction by CP was significantly enhanced by EPHE, especially at higher doses (p ≤ 0.05). The number of primordial, primary, secondary, and Graafian follicles showed a significant decrease in CP groups and EPHE groups showed a significant increase compared to the CP. EPHE showed that the concentration of 1000 mg/kg was more effective than other doses (p ≤ 0.05). Conclusion: In addition to proving the effect of EPHE on the hypothalamic-pituitary-gonadal axis, our investigation showed antioxidant properties, which can be an effective factor in CP-treated rats.
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BACKGROUND: The coronavirus pandemic and health measures related to it have led to an increase in mental health problems. The relatively high incidence of the disease and its mortality rate created anxiety in society. This study aimed to determine the prevalence of fear of the coronavirus (COVID-19) and its relationship with obsessive-compulsive disorder in patients who attended the outpatient clinic of Besat Hospital in Hamadan. METHODS: In this cross-sectional descriptive study, 320 patients who attended the outpatient clinic of Besat Hospital in Hamadan were selected by random sampling method in 2021. Data were collected using the Fear of the coronavirus (COVID-19) questionnaire and obsessive-compulsive disorder scale and analyzed using SPSS software (V16). They were analyzed using Pearson correlation coefficient and independent t-test. RESULTS: The mean ± SD age of the subjects was 34.14 ± 9.30 years and 65% of the study subjects were women. The mean ± SD score on the obsessive-compulsive disorder scale was 32.90 ± 19.87 and the mean ± SD score for fear of coronavirus was 16.82 ± 5.79. The contamination dimension of OCD had the highest score of 9.04 ± 5.46 and stealing had the lowest score of 0.10 ± 0.49. The mean fear of COVID-19 in people who had a history of obsessive-compulsive disorder before the quarantine was significantly higher than in those who did not have it (P = 0.002). Along with the increasing fear of coronavirus scale score, the score of obsessive-compulsive disorders increased except for the stealing dimension (P < 0.001). CONCLUSIONS: The results of the study showed that there was a moderate level of fear of COVID-19 among the study population. Also, a relatively high proportion of study subjects had a weak manifestation of OCD. It seems that two years after the beginning of the Covid-19 coronavirus pandemic, people have adapted to the conditions, and their fear of the disease is reduced.
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COVID-19 , Trastorno Obsesivo Compulsivo , Humanos , Femenino , Adulto Joven , Adulto , Masculino , COVID-19/epidemiología , Estudios Transversales , Trastorno Obsesivo Compulsivo/epidemiología , Trastorno Obsesivo Compulsivo/psicología , Trastornos de Ansiedad , Miedo/psicologíaRESUMEN
BACKGROUND: Women empowerment is effective in successful breastfeeding. Hence,identifying the relationship between psychosocial factors, such as acceptance of feminine norms, and empowerment can be beneficial in designing interventions.. Therefore, this study aimed to determine the relationship between breastfeeding empowerment and conformity to feminine norms. METHODS: This cross-sectional study was conducted on 288 primiparous mothers in the postpartum period using validated questionnaires of conformity to gender norms and breastfeeding empowerment in the following domains: "sufficient knowledge and skills for breastfeeding," "a sense of breastfeeding competence," "conscious belief in the value of breastfeeding," "overcoming breastfeeding problems," "negotiation and obtaining family support" and "self-efficacy in breastfeeding" which were completed through the self-report method. Data were analyzed using the multivariate linear regression test. RESULTS: The mean score of 'conformity to feminine norms' and 'breastfeeding empowerment' were 142.39 and 144.14, respectively. The score of breastfeeding empowerment was positively related to conformity to feminine norms (p = 0.003). Among the dimensions of breastfeeding empowerment, 'mothers' adequate knowledge and skills for breastfeeding' (p = 0.001), 'belief in the value of breastfeeding' (p = 0.008), and 'negotiation and obtaining family support' (p = 0.01) were positively related to conformity to feminine norms. CONCLUSIONS: The results indicate a positive relationship between the level of conformity to feminine norms and breastfeeding empowerment. Accordingly, it is recommended that supporting breastfeeding as a valuable role of women be considered in programs designed to improve breastfeeding empowerment.
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Lactancia Materna , Conformidad Social , Femenino , Humanos , Estudios Transversales , Identidad de Género , Encuestas y Cuestionarios , EmpoderamientoRESUMEN
Recent advances in the artificial pancreas system provide an emerging treatment option for type 1 diabetes. The performance of the blood glucose regulation directly relies on the accuracy of the glucose-insulin modeling. Sorenson model involves the behavior of different organs and offers precise representation. However, the high complexity of such a model makes the controller design procedure a hard task. Therefore, the high-order nonlinear Sorensen model as a popular high-fidelity physiological model is opted in this paper to analyze the glucose-insulin interactions in great detail, and a new robust nonlinear approach to regulate the blood glucose concentration (BGC) in Type-I diabetic patients is proposed. Inspiring the backstepping technique, for designing an acceptable controller, the model is divided into three main subsystems such that in each subsystem, the virtual control input laws are obtained using both Lyapunov stability and input-to-state theorems. Since the measurement of the parameters in the glucose-insulin system is not accurate, parametric uncertainties are defined in the investigated model. Furthermore, owing to the fact that the only measurable state variable is blood glucose, the estimation of inaccessible state variables is an important issue that is properly considered by the unscented Kalman filter (UKF) estimator. The suggested approach is compared to H∞, robust H∞, and linear parameter-varying control approaches. The comparison results on 500 simulated patients imply a remarkable superiority of the proposed controller approach to the compared methods in terms of the BGC tracking and the algorithm robustness in the presence of food intake disturbance patterns.
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Glucemia , Diabetes Mellitus Tipo 1 , Humanos , Insulina , Modelos Biológicos , Conducta AlimentariaRESUMEN
Due to the importance of control actions in spreading coronavirus disease, this paper is devoted to first modeling and then proposing an appropriate controller for this model. In the modeling procedure, we used a nonlinear mathematical model for the covid-19 outbreak to form a T-S fuzzy model. Then, for proposing the suitable controller, multiple optimization techniques including Linear Quadratic Regulator (LQR) and mixed H 2 - H ∞ are taken into account. The mentioned controller is chosen because the model of corona-virus spread is not only full of disturbances like a sudden increase in infected people, but also noises such as unavailability of the exact number of each compartment. The controller is simulated accordingly to validate the results of mathematical calculations, and a comparative analysis is presented to investigate the different situations of the problem. Comparing the results of controlled and uncontrolled situations, it can be observed that we can tackle the devastating hazards of the covid-19 outbreak effectively if the suggested approaches and policies of controlling interventions are executed, appropriately.
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This paper addresses a robust Luenberger observer for an uncertain linear parameter varying (LPV) system based on the concepts of direct searching, Kronecker sum, and small gain theorem. An algorithm is proposed to investigate the situation of the different parts of the initial observer design space, in terms of suitability for being selected as the observer gain or needing elimination due to being an undesirable part. To find the undesirable parts of the design space, the singularity of the Kronecker sum matrix of the estimation error is checked by employing the small gain theorem concept. By excluding undesired parts from the entire design space and checking the remaining parts' feasibility, a suitable solution can be found, appropriately. The performance of the proposed observer design method is illustrated by using numerical examples and an electric ground vehicle (EGV) system for the estimation of the vehicle sideslip angle and the yaw rate. The results prove the appropriateness of the designed observer using the proposed approach.
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Objective: Coronavirus disease 2019 has significantly impacted the rate of emergency department visits among patients with the non-repository disease. Patients with acute appendicitis are also likely to delay their visit to the health care center, which can lead to complications including perforated appendicitis. The aim of this study was to compare the prevalence of perforated appendicitis during the COVID19 and pre-pandemic periods. Methods: This retrospective study was performed on all appendectomies performed during COVID-19, Group A, and one year earlier, Group B. A questionnaire comprising demographic variables (age, gender, occupation, education), clinical variables (white blood cell count, fever), location and type of appendicitis, the status of appendectomy, and duration of hospitalization was completed for all the patients included in the study. Results: The demographic variables were not significantly different among the two groups. The perforation appendicitis rate during the COVID19 pandemic increased compared to the previous year, The difference was not statistically significant. The number of negative appendectomy in group A was significantly less compared to group B. The mean time from the onset of pain to the time of referral was significantly lesser in group A. The mean length of hospital stay in group B was longer than in group A. In terms of fever, patients with perforated appendicitis in group B had a higher fever than in group A, which was statistically significant. Conclusion: A non-significant increase in the number of perforated appendicitis cases during the pandemic period. Duration of hospitalization and fever was significantly greater in pre-pandemic perforated appendicitis cases.
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Breast cancer (BC) is one of the most common cancers in females and is responsible for the highest cancer-related deaths following lung cancer. The complex tumor microenvironment and the aggressive behavior, heterogenous nature, high proliferation rate, and ability to resist treatment are the most well-known features of BC. Accordingly, it is critical to find an effective therapeutic agent to overcome these deleterious features of BC. Resveratrol (RES) is a polyphenol and can be found in common foods, such as pistachios, peanuts, bilberries, blueberries, and grapes. It has been used as a therapeutic agent for various diseases, such as diabetes, cardiovascular diseases, inflammation, and cancer. The anticancer mechanisms of RES in regard to breast cancer include the inhibition of cell proliferation, and reduction of cell viability, invasion, and metastasis. In addition, the synergistic effects of RES in combination with other chemotherapeutic agents, such as docetaxel, paclitaxel, cisplatin, and/or doxorubicin may contribute to enhancing the anticancer properties of RES on BC cells. Although, it demonstrates promising therapeutic features, the low water solubility of RES limits its use, suggesting the use of delivery systems to improve its bioavailability. Several types of nano drug delivery systems have therefore been introduced as good candidates for RES delivery. Due to RES's promising potential as a chemopreventive and chemotherapeutic agent for BC, this review aims to explore the anticancer mechanisms of RES using the most up to date research and addresses the effects of using nanomaterials as delivery systems to improve the anticancer properties of RES.
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Antineoplásicos , Neoplasias de la Mama , Estilbenos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Neoplasias de la Mama/patología , Línea Celular Tumoral , Cisplatino/farmacología , Docetaxel , Doxorrubicina/farmacología , Femenino , Humanos , Paclitaxel , Polifenoles/farmacología , Resveratrol/farmacología , Resveratrol/uso terapéutico , Estilbenos/farmacología , Estilbenos/uso terapéutico , Microambiente Tumoral , AguaRESUMEN
At the forefront of biopharmaceutical industry, the messenger RNA (mRNA) technology offers a flexible and scalable platform to address the urgent need for world-wide immunization in pandemic situations. This strategic powerful platform has recently been used to immunize millions of people proving both of safety and highest level of clinical efficacy against infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here we provide preclinical report of COReNAPCIN®; a vaccine candidate against SARS-CoV-2 infection. COReNAPCIN® is a nucleoside modified mRNA-based vaccine formulated in lipid nanoparticles (LNPs) for encoding the full-length prefusion stabilized SARS-CoV-2 spike glycoprotein on the cell surface. Vaccination of C57BL/6 and BALB/c mice and rhesus macaque with COReNAPCIN® induced strong humoral responses with high titers of virus-binding and neutralizing antibodies. Upon vaccination, a robust SARS-CoV-2 specific cellular immunity was also observed in both mice and non-human primate models. Additionally, vaccination protected rhesus macaques from symptomatic SARS-CoV-2 infection and pathological damage to the lung upon challenging the animals with high viral loads of up to 2 × 108 live viral particles. Overall, our data provide supporting evidence for COReNAPCIN® as a potent vaccine candidate against SARS-CoV-2 infection for clinical studies.
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Initiation and development of cancer depend on multiple factors that mutations in genes and epigenetic level can be considered as important drivers. Epigenetic factors include a large family of members and understanding their function in cancer has been a hot topic. LncRNAs are RNA molecules with no capacity in synthesis of proteins, and they have regulatory functions in cells. LncRNAs are localized in nucleus and cytoplasm, and their abnormal expression is related to development of tumor. This manuscript emphasizes on the role of lncRNA H19 in various cancers and its association with tumor hallmarks. The function of lncRNA H19 in most tumors is oncogenic and therefore, tumor cells increase its expression for promoting their progression. LncRNA H19 contributes to enhancing growth and cell cycle of cancers and by EMT induction, it is able to elevate metastasis rate. Silencing H19 induces apoptotic cell death and disrupts progression of tumors. LncRNA H19 triggers chemo- and radio-resistance in cancer cells. miRNAs are dually upregulated/down-regulated by lncRNA H19 in increasing tumor progression. Anti-cancer agents reduce lncRNA H19 in impairing tumor progression and increasing therapy sensitivity. A number of downstream targets and molecular pathways for lncRNA H19 have been detected in cancers including miRNAs, RUNX1, STAT3, ß-catenin, Akt2 and FOXM1. Clinical studies have revealed potential of lncRNA H19 as biomarker and its association with poor prognosis. LncRNA H19 can be transferred to cancer cells via exosomes in enhancing their progression.
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MicroARNs , Neoplasias , ARN Largo no Codificante , Línea Celular Tumoral , Proliferación Celular/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , beta Catenina/metabolismoRESUMEN
BACKGROUND: We decided to compare some inflammatory, and oxidative stress markers, as well as lipid profiles between the obese and non-obese patients with type 2 diabetes considering ApoB gene polymorphism. METHODS: one-hundred sixty two patients with type 2 diabetes were included in this study. ApoB genotyping was conducted by the polymerase chain reaction. Serum interleukin-(IL-18), pentraxin-3 (PTX-3), and high sensitive- C reactive protein (hs-CRP) was measured as the inflammatory markers. Moreover, copper-zinc superoxide dismutase (Cu/Zn-SOD), total antioxidant capacity (TAC) and 8-isoprostane F2α were analyzed for oxidative stress assessment. Anthropometric indices and lipid profiles were measured. RESULTS: Adjusted for confounders, serum hs-CRP (p = 0.04), LDL-C (p = 0.01), LDL-C/HDL-C (p = 0.04), and TG (p = 0.02) were significantly lower at the Homozygous Insertion (Ins)/Ins vs. deletion (Del) allele carriers in the obese patients. Serum TAC was significantly lower at the obese Del allele carriers than Ins/Ins Homozygous (p = 0.03). Serum hs-CRP (p = 0.006), and 8-IsoprostanF2α (P = 0.04) were significantly higher in the obese Del allele carriers than non-obese. Serum Cu/Zn-SOD was significantly higher in the non-obese Del allele carriers than obese (p = 0.04). CONCLUSION: Inflammation, dyslipidemia, and oxidative stress are higher in the Obese Del allele carriers with type 2 diabetes which prone them to other chronic disorders.
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Apolipoproteínas B , Diabetes Mellitus Tipo 2 , Dislipidemias , Alelos , Apolipoproteína B-100 , Apolipoproteínas B/genética , Estudios Transversales , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/genética , Dislipidemias/genética , Humanos , Inflamación/genética , Obesidad/complicaciones , Obesidad/genética , Estrés Oxidativo/genéticaRESUMEN
This paper studies the robust stability of the fractional-order (FO) LTI systems with polytopic uncertainty. Generally, the characteristic polynomial of the system dynamic matrix is not an affine function of the uncertain parameters. Consequently, the robust stability of the uncertain system cannot be evaluated by well-known approaches including LMIs or exposed edges theorem. Here, an over-parameterization technique is developed to convert the main characteristic polynomial into a set of local over-parameterized characteristic polynomials (LOPCPs). It is proved that the robust stability of LOPCPs implies the robust stability of the uncertain system. Then, an algorithm is proposed to explore system's robust stability through investigating the robust stability of these LOPCPs based on the exposed edges idea. For the sake of feasibility comparison, extensive examples are elaborated that reveal the superiority of the proposed algorithm.
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BACKGROUND: Regarding the inconclusive results of previous investigations, this study aimed to determine the association between pathology, as a possible predictor, with remission outcomes, to know the role of pathology in the personalized decision making in acromegaly patients. METHODS: A retrospective cohort study was performed on the consecutive surgeries for growth hormone (GH) producing pituitary adenomas from February 2015 to January 2021. Seventy-one patients were assessed for granulation patterns and prolactin co-expression as dual staining adenomas. The role of pathology and some other predictors on surgical remission was evaluated using logistic regression models. RESULTS: Among 71 included patients, 34 (47.9%) patients had densely granulated (DG), 14 (19.7%) had sparsely granulated (SG), 23 (32.4%) had dual staining pituitary adenomas. The remission rate was about 62.5% in the patients with SG and DG adenomas named single staining and 52.2% in dual staining groups. Postoperative remission was 1.53-folds higher in the single staining adenomas than dual staining-one (non-significant). The remission rate was doubled in DG group compared to two other groups (non-significant). By adjusting different predictors, cavernous sinus invasion and one-day postoperative GH levels decreased remission rate by 91% (95% CI: 0.01-0.67; p = 0.015) and 64% (95% CI: 0.19-0.69; p < 0.001), respectively. Responses to the medications were not significantly different among three groups. CONCLUSION: Various pathological subtypes of pituitary adenomas do not appear to have a predictive role in estimating remission outcomes. Cavernous sinus invasion followed by one-day postoperative GH is the strongest parameter to predict biochemical remission.
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Acromegalia/fisiopatología , Adenoma/patología , Hormona de Crecimiento Humana/metabolismo , Neoplasias Hipofisarias/patología , Adenoma/clasificación , Adenoma/metabolismo , Adenoma/cirugía , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Neoplasias Hipofisarias/clasificación , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/cirugía , Pronóstico , Inducción de Remisión , Estudios RetrospectivosRESUMEN
Current outbreaks of the COIVD-19 pandemic demonstrate a global threat. In this paper, a conceptual model is developed for the COVID-19 pandemic, in which the people in society are divided into Susceptible, Exposed, Minor infected (Those who need to be quarantined at home), Hospitalized (Those who are in need of hospitalization), Intensive infected (ventilator-in-need infected), Recovered and Deceased. In this paper, first, the model that is briefly called SEMHIRD for a sample country (Italy as an example) is considered. Then, exploiting the real data of the country, the parameters of the model are obtained by assuming some basis functions on the collected data and solving linear least square problems in each window of data to estimate the time-varying parameters of the model. Thus, the parameters are updated every few days, and the system behavior is modeled according to the changes in the parameters. Then, the Linear Parameter Varying (LPV) Model of COVID19 is derived, and its stability analysis is presented. In the end, the influence of different levels of social distancing and quarantine on the variation of severely infected and hospitalized people is studied.
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INTRODUCTION: The recommended position for measuring Intra-Abdominal Pressure (IAP) is the supine position. However, patients put in this position are prone to Ventilator-associated pneumonia. This study was done to evaluate the relationship between bed head angle and IAP measurements of intubated patients in the intensive care unit. METHODS: In this clinical trial, seventy-six critically ill patients under mechanical ventilation were enrolled. IAP measurement was performed every 8 hours for 24 hours using the KORN method in three different degrees of the head of bed (HOB) elevation (0 ° , 15 ° , and 30 ° ). Bland-Altman analysis was performed to identify the bias and limits of agreement among the three HOBs. According to World Society of the Abdominal Compartment Syndrome (WSACS), we can consider two IAP techniques equivalent if a bias of <1 mmHg and limits of agreement of - 4 to +4 were found between them. Data were analyzed using SPSS statistical software (v. 19), and the significance level was considered as 0.05. RESULTS: The prevalence of intra-abdominal hypertension was 18.42%. Mean ± standard deviation (SD) of IAP were 8.44 ± 4.02 mmHg for HOB angle 0°, 9.58 ± 4.52 for HOB angle 15 ° , and 11.10 ± 4.73 for HOB angle 30o (p = 0.0001). The IAP measurement bias between HOB angle 0°and HOB angle 15° was 1.13 mmHg. This bias was 2.66 mmHg between HOB angle 0° and HOB angle 30°. CONCLUSION: Elevation of HOB angle from 0 to 30 degree significantly increases IAP. It seems that the measurement of IAP at HOB angle 15° was more reliable than 30°.
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BACKGROUND: Neuroendocrine tumor (NET) with adrenocorticotropic hormone (ACTH) secretion are very rare. To our knowledge, no follow-up study is published for ACTH-secreting NET, regardless of the primary site, to show second occurrence of tumor after a long follow-up, following resection of primary tumor. CASE PRESENTATION: Here, we describe a 49-year-old-man with cushingoid feature, drowsiness and quadriparesis came to emergency department at December 2005. Laboratory tests revealed hyperglycemia, metabolic alkalosis, severe hypokalemia, and chemical evidence of an ACTH-dependent hypercortisolism as morning serum cortisol of 57 µg /dL without suppression after 8 mg dexamethasone suppression test, serum ACTH level of 256 pg/mL, and urine free cortisol of > 1000 µg /24 h. Imaging showed only bilateral adrenal hyperplasia, without evidence of pituitary adenoma or ectopic ACTH producing tumors. Importantly, other diagnostic tests for differentiating Cushing disease (CD) from ectopic ACTH producing tumor, such as inferior petrosal sinus sampling (IPSS), corticotropin releasing hormone (CRH) stimulation test, octreotide scan or fluorodeoxyglucose (FDG)-positron emission tomography (PET) scan were not available in our country at that time. Therefore, bilateral adrenalectomy was performed that led to clinical and biochemical remission of hypercortisolism and decreased ACTH level to < 50 pg/mL, findings suggestive of a primary focus of NET in adrenal glands. After 11 years uncomplicated follow up, the ACTH level elevated up to 341 pg/mL and re-evaluation showed a 2 cm nodule in the middle lobe of the right lung. Surgical excision of the pulmonary nodule yielded a carcinoid tumor with positive immunostaining for ACTH; leading to decrease in serum ACTH level to 98 pg/mL. Subsequently after 7 months, serum ACHT levels rose again. More investigation showed multiple lung nodules with metastatic bone lesions accompanied by high serum chromogranin level (2062 ng/mL), and the patient managed as a metastatic NET, with bisphosphonate and somatostatin receptor analogues. CONCLUSION: This case of surgically-treated NET showing a secondary focus of carcinoid tumor after one decade of disease-free follow-up emphasizes on the importance of long-term follow-up of ACTH-secreting adrenal NET.