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Post hepatectomy Liver Failure (PHLF) is a fatal complication, especially after major liver resection. Insufficient remnant liver volume is a common cause of postoperative liver failure. Many strategies have been applied to induce the remnant liver hypertrophy: Portal vein embolization (PVE), PVE combined with hepatic vein embolization (LVD), two staged liver resection, Associated liver partition with portal vein ligation for staged hepatectomy (ALPPS). We present a case of a 39-year-old male patient who underwent LVD for preoperative liver hypertrophy. After LVD, the patient underwent additional artery embolization, and the patient's remaining liver volume increased by 63.2% in 7 weeks. The patient underwent a right hepatectomy and was discharged after 10 days, with no complications of postoperative liver failure. Simultaneous portal and hepatic vein embolization is a technique that has been applied recently because it can significantly promote the speed and extent of liver hypertrophy before major liver resection compared to portal vein embolization procedure alone. In this case, additional hepatic artery embolization may be an important factor lead to hypertrophy of the remnant liver, thereby shortening the waiting time for surgery and reducing the risk of tumor progression. Liver venous deprivation is safe and feasible to perform. Additional hepatic artery embolization may accelerate the hypertrophy of the remnant liver.
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Backgrounds/aims: To evaluate the outcomes of hepatocellular carcinoma (HCC) patients who underwent right anatomical hepatectomy using the combination of the extrahepatic Glissonean pedicle approach (Takasaki's technique) and liver hanging maneuver (LHM) (Belghiti's technique). Patients and methods: A retrospective analysis of 30 cases of HCC treated with right hepatectomy using extrahepatic Glissonean pedicle approach and LHM by only one surgeon at our department from March 2020 to August 2023. Clinical characteristics, pathological results, postoperative outcomes, and survival rate were analyzed. Results: Among the 30 HCC patients analyzed, males accounted for 96.7% of patients. The mean age was 54.9±11 years. 96.7% had normal preoperative liver function (Child-Pugh A). LHM with an extrahepatic Glissonean approach was feasible in 100% of cases with minor blood loss, no blood transfusion, intraoperative complications, or perioperative mortality. The mean operative time was 123.8±29.0 min. The mean hospital stay was 9.37±4.02 days. Postoperative liver failure accounted for 6.7%. Pathological results: 63.3% moderately differentiated HCC; 36.7% poorly differentiated HCC. 1-year, 2-year, and 3-year survival rates were 86.1, 73.8, and 59.0%, respectively. Recurrence was witnessed in 13 (43.3%) cases, with 6 (20%) cases in remnant liver. 1-year, 2-year, and 3-year disease-free survival were 69.3, 42.0, and 28.0%, respectively. Conclusion: Right anatomical hepatectomy using extrahepatic Glissonean pedicle approach combined LHM for HCC was feasible and safe at our high-volume oncology center in a developing country.
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Background: Ocrelizumab, a humanised anti-CD20 monoclonal, is a highly effective treatment for relapsing-remitting multiple sclerosis (RRMS). The long-term safety of B-cell depletion in RRMS, however, is uncertain and there are no data on dose reduction of ocrelizumab as a risk mitigation strategy. This study aimed to evaluate the effectiveness and safety of reducing ocrelizumab dose from 600 to 300 mg in patients with RRMS. Method: Data were collected through the Townsville neurology service. Following the standard randomised controlled trial regimen of 600 mg every 6 months for 2 years, sequential patients consented to dose reduction to 300 mg every 6 months. Patients were included if they were diagnosed with RRMS and received at least one reduced dose of ocrelizumab. Relapse, disability progression, new MRI lesions, CD19+ cell counts and immunoglobulin concentrations were analysed. Results: A total of 35 patients, treated with 177 full and 107 reduced doses, were included. The mean follow-up on reduced dose was 17 (1-31) months. We observed no relapses or new MRI activity in the cohort receiving the reduced dose, accompanied by persistent CD19+B cell depletion (≤0.05×109/L). Mean IgG, IgA and IgM levels remained stable throughout the study. No new safety concerns arose. Conclusions: In this single-centre observational study, dose reduction of ocrelizumab from 600 to 300 mg every 6 months after 2 years appeared to maintain efficacy in terms of new inflammatory disease activity. A randomised trial may be warranted to confirm this and explore the impact of dose reduction on long-term safety.
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INTRODUCTION: Tuberculosis is a chronic infectious disease that often has a latent period after the initial infection. Tuberculosis most often affects the lungs but it can also affect other parts of the body. Vietnam is in pandemic area of tuberculosis. CASE REPORT: We present a rare case of a 42-year-old male patient admitted to the hospital with a history of progressive jaundice. Magnetic resonance imaging (MRI) revealed a 26 × 33 mm tuberculous mass located at the intersection between the cystic duct and the common hepatic duct, leading to dilation of the intrahepatic biliary ducts on both sides. Initially diagnosed with a Klatskin type II tumor, the patient underwent surgery to remove the mass and create a biliary-enteric anastomosis. However, the pathological report of the postoperative specimens concluded a diagnosis of necrotizing granulomatous inflammation caused by tuberculosis. CASE DISCUSSION: Obstructive jaundice secondary to tuberculosis is a rare condition that can be caused due to the tuberculous enlargement of the pancreatic head, tuberculous lymphadenitis, tuberculous biliary strictures, or a tuberculous retroperitoneal mass. Extrapulmonary tuberculosis usually results from hematogenous dissemination or contiguous spread from adjacent organs. Symptoms vary depending on the affected organ but typically include fever, fatigue, and weight loss. Hepatobiliary tuberculosis is usually secondary to pulmonary or gastrointestinal tuberculosis. CONCLUSION: Hepatobiliary tuberculosis is a rare disease that affects the liver and bile duct system. It is difficult to diagnose because it does not have any specific symptoms and can be easily misdiagnosed with other diseases.
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Graphitic carbon nitride (g-C3N4) has proved to be a promising heterogeneous photocatalyst in the visible range. It can be used, among others, for the oxidative conversion of environmentally harmful nitrophenols occurring in wastewater. However, its photocatalytic activity needs to be enhanced, which can be achieved by modification with various dopants. In our work, copper-modified g-C3N4 was prepared by ultrasonic impregnation of the pristine g-C3N4 synthesized from thiourea. The morphology, microstructure, and optical properties of the photocatalysts were characterized by XRD, FT-IR, DRS, SEM, XPS, and TEM. DRS analysis indicated a slight change in both the CB and the VB energies of Cu/g-C3N4 compared to those of g-C3N4. The efficiency of the photocatalysts prepared was tested by the degradation of nitrophenols. Copper modification caused a sevenfold increase in the rate of 4-nitrophenol degradation in the presence of H2O2 at pH = 3. This dramatic enhancement can be attributed to the synergistic effect of copper and H2O2 in this photocatalytic system. A minor Fenton reaction role was also detected. The reusability of the Cu/g-C3N4 catalyst was demonstrated through five cycles. Copper-modified g-C3N4 with H2O2 proved to be applicable for efficient visible-light-driven photocatalytic oxidative degradation of nitrophenols.
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Critically ill patients are characterized by substantial pathophysiological changes that alter the pharmacokinetics (PK) of hydrophilic antibiotics, including carbapenems. Meropenem is a key antibiotic for multidrug-resistant Gram-negative bacilli, and such pathophysiological alterations can worsen treatment outcomes. This study aimed to determine the population PK of meropenem and to propose optimized dosing regimens for the treatment of multidrug-resistant Klebsiella pneumoniae in critically ill patients. Two plasma samples were collected from eligible patients over a dosing interval. Nonparametric population PK modeling was performed using Pmetrics. Monte Carlo simulations were applied to different dosing regimens to determine the probability of target attainment and the cumulative fraction of response, taking into account the local MIC distribution for K. pneumoniae. The targets of 40% and 100% for the fraction of time that free drug concentrations remained above the MIC (ƒT>MIC) were tested, as suggested for critically ill patients. A one-compartment PK model using data from 27 patients showed high interindividual variability. Significant PK covariates were the 8-h creatinine clearance for meropenem and the presence of an indwelling catheter for pleural, abdominal, or cerebrospinal fluid drainage for the meropenem volume of distribution. The target 100% ƒT>MIC for K. pneumoniae, with a MIC of ≤2 mg/liter, could be attained by the use of a continuous infusion of 2.0 g/day. Meropenem therapy in critically ill patients could be optimized for K. pneumoniae isolates with an MIC of ≤2 mg/liter by using a continuous infusion in settings with more than 50% isolates have a MIC of ≥32mg/L.
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Enfermedad Crítica , Klebsiella pneumoniae , Humanos , Meropenem/farmacocinética , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Método de MontecarloRESUMEN
INTRODUCTION: To find out risk factors for disease severity and mortality of pediatric COVID-19 in the fourth wave of COVID-19 in Vietnam. METHODS: This retrospective cohort study was performed at Children's Hospital 1 from July to December 2021. All children with COVID-19 confirmed by a positive Realtime RT-PCR SARS-CoV-2 result and treated at COVID-19 department for at least 72 h were included. RESULTS: Of the 850 cases admitting to COVID-19 department, 555 children with COVID-19 confirmed by positive RT-PCR and treated at our center for more than 72 h. Median age of confirmed cases was 22.3 (IQR: 3.2-88.6) months, 55.1% were male, and 84.5% had a history of close contact with confirmed COVID-19 patients. The rate of mild, moderate and severe/critical cases was 73,7%, 9.0% and 17.3%, respectively. One hundred ninety-two children (34.6%) had underlying diseases, in which, neurologic disease was the most common underlying disease (7.9%). Underlying disease, dyspnea, elevated CRP >20 mg/L and elevated ferritin were independent factors related to severe illness. Twenty-point two percent of patients in our study needed respiratory support, including 22 invasive mechanical ventilation cases. Eighteen cases (3.2%) died because of severe comorbidities, poor response to treatment. CONCLUSIONS: In our study, the severe/critical and mortality rates in pediatric COVID-19 cases were relatively high. All fatal cases had severe comorbidities. Underlying disease, dyspnea, and elevated inflammatory markers were independent factors related to severity in pediatric COVID-19 cases.
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COVID-19 , Pueblo Asiatico , COVID-19/epidemiología , Niño , Preescolar , Disnea , Femenino , Hospitales , Humanos , Lactante , Masculino , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Vietnam/epidemiologíaRESUMEN
Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease that most commonly affects women of childbearing age. The symptoms of the disease are managed with a multitude of topical and systemic medications. The course of HS changes during pregnancy, and some women can experience postpartum flares. Thus, it is important to be aware of how pregnancy may alter the treatment plan for women and impact their choice to breastfeed. The following review summarizes medical management for HS and its safety during pregnancy and breastfeeding.
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Hidradenitis Supurativa , Lactancia Materna , Femenino , Hidradenitis Supurativa/diagnóstico , Humanos , Embarazo , PielRESUMEN
Lower-limb exoskeletons are a promising option to increase the mobility of persons with leg impairments in a near future. However, it is still challenging for them to ensure the necessary stability and agility to face obstacles, particularly the variety that makes the urban environment. That is why most of the lower-limb exoskeletons must be used with crutches: the stability and agility features are deferred to the patient. Clinical experience shows that the use of crutches not only leads to shoulder pain and exhaustion, but also fully occupies the hands for daily tasks. In November 2020, Wandercraft presented Atalante Evolution, the first self-stabilized and crutch-less exoskeleton, to the powered exoskeleton race of the Cybathlon 2020 Global Edition. The Cybathlon aims at promoting research and development in the field of powered assistive technology to the public, contrary to the Paralympics where only participants with unpowered assistive technology are allowed. The race is designed to represent the challenges that a person could face every day in their environment: climbing stairs, walking through rough terrain, or descending ramps. Atalante Evolution is a 12 degree-of-freedom exoskeleton capable of moving dynamically with a complete paraplegic person. The challenge of this competition is to generate and execute new dynamic motions in a short time, to achieve different tasks. In this paper, an overview of Atalante Evolution system and of our framework for dynamic trajectory generation based on the direct collocation method will be presented. Next, the flexibility and efficiency of the dynamic motion generation framework are demonstrated by our tools developed for generating the important variety of stable motions required by the competition. A smartphone application has been developed to allow the pilot to choose between different modes and to control the motion direction according to the real situation to reach a destination. The advanced mechatronic design and the active cooperation of the pilot with the device will also be highlighted. As a result, Atalante Evolution allowed the pilot to complete four out of six obstacles, without crutches. Our developments lead to stable dynamic movements of the exoskeleton, hands-free walking, more natural stand-up and turning moves, and consequently a better physical condition of the pilot after the race compared to the challengers. The versatility and good results of these developments give hope that exoskeletons will soon be able to evolve in challenging everyday-life environments, allowing patients to live a normal life in complete autonomy.
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Stooped posture, which is usually aggravated during walking, is one of the typical postural deformities in patients with parkinsonism. However, the degree of stooped posture is difficult to quantitatively measure during walking. Furthermore, continuous feedback on posture is also difficult to provide. The purpose of this study is to measure the degree of stooped posture during gait and to investigate whether vibration feedback from sensor modules can improve a patient's posture. Parkinsonian patients with stooped posture were recruited for this study. Two wearable sensors with three-axis accelerometers were attached, one at the upper neck and the other just below the C7 spinous process of the patients. After being calibrated in the most upright posture, the sensors continuously recorded the sagittal angles at 20 Hz and averaged the data at every second during a 6 min walk test. In the control session, the patients walked with the sensors as usual. In the vibration session, sensory feedback was provided through vibrations from the neck sensor module when the sagittal angle exceeded a programmable threshold value. Data were collected and analyzed successfully in a total of 10 patients. The neck flexion and back flexion were slightly aggravated during gait, although the average change was <10° in most patients in both measurement sessions. Therefore, it was difficult to evaluate the effect of sensory feedback through vibration. However, some patients showed immediate response to the feedback and corrected their posture during gait. In conclusion, this preliminary study suggests that stooped posture could be quantitatively measured during gait by using wearable sensors in patients with parkinsonism. Sensory feedback through vibration from sensor modules may help in correcting posture during gait in selected patients.
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Trastornos Parkinsonianos , Dispositivos Electrónicos Vestibles , Marcha , Humanos , Postura , CaminataRESUMEN
The Pesticide Concentration in Paddy Field (PCPF-1) model has been successfully used to predict the fate and transport of granular pesticides applied to the paddy fields. However, it is not applicable for pesticides in foliar formulation while previous studies have reported that foliar application may increase the risks of rice pesticide contamination to the aquatic environment due to pesticide wash-off from rice foliage. In this study, we developed and added a foliar application module into the PCPF-1 model to improve its versatility regarding pesticide application methods. In addition, some processes of the original model such as photodegradation were simplified. The updated model was then validated with data from previous studies. Critical parameters of the model were calibrated using the Sequential Uncertainty Fitting version 2 (SUFI-2) algorithm. The calibrated model simulated pesticide dissipation trend and concentrations with moderate accuracy in the two paddy compartments including rice foliage and paddy water. The accuracy of the predicted soil concentrations could not be evaluated since no observed data were available. Although the p-factor and r-factor obtained using the SUFI2 algorithm indicated that the uncertainty encompassed in the predicted concentrations was rather high, the daily predicted pesticide concentrations in rice foliage and paddy water were satisfactory based on the NSE values (0.36-0.89). The updated PCPF-1 model is a flexible tool for the environmental risk assessment of pesticide losses and the evaluation of agricultural management practices for mitigating pesticide pollution associated with rice production.
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Oryza , Plaguicidas , Contaminantes del Suelo , Contaminantes Químicos del Agua , Modelos Teóricos , Plaguicidas/análisis , Suelo , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
PURPOSE: The purpose of study is to investigate the dosimetry of electron intraoperative radiotherapy (IOERT) of the Intraop Mobetron 2000 mobile LINAC in treatments outside of the breast. After commissioning and external validation of dosimetry, we report in vivo results of measurements for treatments outside the breast in a large patient cohort, and investigate if the presence of inhomogeneities can affect in vivo measurements. METHODS AND MATERIALS: Applicator factors and profile curves were measured with a stereotactic diode. The applicators factors of the 6 cm flat and beveled applicators were also confirmed with radiochromic films, parallel-plate ion chamber and by an external audit performed with ThermoLuminescent Dosimeters (TLDs). The influence of bone on dose was investigated by using radiochromic films attached to an insert equivalent to cortical bone, immersed in the water phantom. In vivo dosimetry was performed on 126 patients treated with IOERT using metal oxide-silicon semiconductor field effect transistors (MOSFETs) placed on the tumor bed. RESULTS: Relatively small differences were found among different detectors for measurements of applicator factors. In the external audit, the agreement with the TLD was mostly within ±0.2%. The largest increase of dose due to the presence of cortical bone insert was +6.0% with energy 12 MeV and 3 cm applicator. On average, in vivo dose was significantly (+3.1%) larger than prescribed dose. CONCLUSION: IOERT in applications outside the breast results in low discrepancies between in vivo and prescribed doses, which can be also explained with the presence of tissue inhomogeneity.
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Mama/diagnóstico por imagen , Electrones/uso terapéutico , Neoplasias/diagnóstico por imagen , Neoplasias/radioterapia , Fantasmas de Imagen , Radiometría/métodos , Radioterapia/métodos , Huesos/diagnóstico por imagen , Femenino , Dosimetría por Película , Humanos , Periodo Intraoperatorio , Masculino , Aceleradores de Partículas , Reproducibilidad de los Resultados , Semiconductores , Silicio/química , Dosimetría TermoluminiscenteRESUMEN
Seasonal influenza virus causes acute respiratory tract infections, which can be severe in children and the elderly. At present, rapid influenza diagnostic tests (RIDTs) are popular at clinical sites because they enable early diagnosis and avoid unnecessary use of antibiotics; in addition, high risk patients with underlying disease can be given antiviral drugs. However, the sensitivity and specificity of some of those tests are relatively poor. To overcome these problems, nucleic acid-based molecular point-of-care tests have been developed; however, they are significantly more expensive than RIDTs. Previously, the authors developed real-time reverse transcription loop-mediated isothermal amplification (rRT-LAMP) assays using a quenching primer to detect influenza viruses. However, the assay is limited to laboratory use because it requires a nucleic acid purification step and preparation of reaction mixtures on ice. Therefore, the authors developed and validated direct rRT-LAMP assays that require no nucleic acid purification steps using commercial RNA isolation kits, and no storage and handling of reagents on ice. These assays can be performed within 10-30 min and require only mixing a clinical specimen with extraction reagent followed by addition of a lyophilized detection reagent. The established assay showed high sensitivity and specificity when validated using 310 clinical specimens. Thus, the assay is a powerful tool for molecular diagnosis of seasonal influenza virus infection in the clinic.
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Gripe Humana/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Transcripción Reversa , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cartilla de ADN/genética , Femenino , Fluorescencia , Humanos , Gripe Humana/virología , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular/normas , ARN Viral/genética , Infecciones del Sistema Respiratorio/virología , Sensibilidad y Especificidad , Adulto JovenRESUMEN
The SPEC model (Predicted Environmental Concentrations in agricultural Soils) was developed and improved for the simulation of pesticide runoff. The model was applied to the Sakaecho upland bare soil field (Tokyo, Japan) to predict runoff water, sediment concentration in runoff water, pesticide concentrations in runoff water, and runoff sediment (clothianidin and imidacloprid) under artificial rainfall conditions. The results showed that the simulated time to first runoff agreed very well with the observed data. The simulated cumulative runoff, sediment yield, and imidacloprid concentration in sediment agreed well with the observed data (Nash-Sutcliffe Efficiency (NSE)>0.75). The simulated runoff rate agreed reasonably well with the observed data (NSE >0.5). The predicted clothianidin concentrations in sediment and in runoff water had acceptable agreement with the observed data (NSE >0). The results implied the model's potential to predict runoff water, sediment yield, and pesticide runoff.
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BACKGROUND: The clinical epidemiology and disease prognosis in patients with acute respiratory distress syndrome (ARDS) have not yet been fully elucidated in Vietnam. METHODS: We conducted a retrospective observational study at a national tertiary hospital in Hanoi, Vietnam. Participants were adult patients (age ≥18 years) who were admitted and diagnosed with ARDS during 2015-2017. Data on patients' general and clinical conditions, radiographic findings, ventilator settings, gas exchange, and treatment methods were collected and compared between survivors and non-survivors. Risk factors for mortality were assessed using logistic regression analysis. RESULTS: Among 126 eligible patients with ARDS admitted to the central tertiary hospital in Vietnam, we observed high mortality (57.1%). Of the total patients, 91.3% were transferred from local hospitals with a diagnosis of severe pneumonia and then diagnosed with ARDS at the central hospital. At the time of admission, 53.2% of patients had severe ARDS, 37.3% had moderate ARDS, and 9.5% had mild ARDS. The mean (standard deviation) sequential organ failure assessment (SOFA) score was 9.5 (3.4) in non-survivors and 7.4 (3.4) in survivors (p = 0.002). Although there was no significant difference in PaO2/FiO2 on admission between non-survivors and survivors, that on day 3 after admission was significantly different (p = 0.002). Logistic regression revealed that PaO2/FiO2 on day 3 [odds ratio (OR), 1.010; 95% confidence interval (CI), 1.003-1.017], length of stay in a local hospital before admission to the central hospital (OR, 1.122; 95% CI, 1.042-1.210) due to stable condition, and SOFA score on Day 1 (OR, 0.842; 95% CI, 0.708-1.002) were independent factors in patient survival. CONCLUSIONS: Patients with ARDS admitted the central tertiary hospital had severe illness and high mortality. Most patients were transferred from local hospitals. Improvements in human, medical, and sociological resources in local will contribute to reducing the mortality of ARDS in Vietnam.
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Síndrome de Dificultad Respiratoria , Adolescente , Adulto , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome de Dificultad Respiratoria/diagnóstico , Síndrome de Dificultad Respiratoria/mortalidad , Síndrome de Dificultad Respiratoria/terapia , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Vietnam/epidemiologíaRESUMEN
Tuberculosis (TB) is a rare but known cause of acute respiratory distress syndrome (ARDS) with a high mortality. Veno-venous extracorporeal membrane oxygenation (VV-ECMO) may be an alternative option for treating TB-induced ARDS. However, the literature on TB-induced ARDS treated with VV-ECMO is limited and the most of them were prolonged therapy. We report on a-48-year-old man with TB-induced ARDS who was successfully treated by short-term use of VV-ECMO (5 days). He was developed symptoms and hospitalized with severe dyspnea in a local hospital for 3 days before admission to our hospital. At the time when he was transferred to our hospital, his chest computed tomography showed bilateral, diffuse and consolidative shadows all over the lungs, the ratio of partial pressure of arterial oxygen to the fraction of inspired oxygen (PaO2/FiO2) was 50â¯mmHg, and respiratory system compliance was 12.5 mL/cmH2O. Two days after admission, Mycobacterium tuberculosis was detected by a sputum smear examination and he was diagnosed with TB-induced ARDS. VV-ECMO support was then initiated with administration of anti-TB drugs and systemic corticosteroid treatment. On the 4thday of ECMO support, his PaO2/FiO2 increased to 400â¯mmHg and lung compliance increased to 45 mL/cmH2O. He was weaned from ECMO on the 5th day of ECMO support and was extubated at the 8th day. He was discharged from hospital on the 47th hospitalized day and continued anti-TB medication at home. VV-ECMO is effective for TB-induced ARDS even in short-term administration if progression of ARDS is rapid.
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The widespread use of titanium dioxide nanoparticles (NPs) and their inevitable release into aquatic environments have caused great concerns about their ecotoxicity. However, the chronic toxicity to TiO2 NPs of aquatic organisms has not been fully understood. In particular, research is lacking on the influence of the crystalline forms of TiO2 NPs on their mechanisms of toxicity. This study investigated the chronic toxicity (i.e., 21-day toxicity tests) of 5 types of TiO2 NPs with various percentages of crystalline forms on Daphnia magna. Results revealed that the crystalline form composed of 80% anatase and 20% rutile (i.e., the M1 form) had the highest energy band gap (i.e., Eg, the energy interval between the valence band edge and the conduction band edge) and caused maximal D. magna mortality compared with other crystalline forms. The crystalline form comprising 100% rutile (i.e., the R-S form) had the lowest Eg and exhibited a minimal effect on the physiological parameters of D. magna. Moreover, in a suitable environment without TiO2 NPs, D. magna progenies could recover to a normal physiological level (e.g., the mortalities of D. magna progenies were lower than those of parental D. magna that were exposed to TiO2 NPs at a concentration of 0.5â¯mg/L). Correlation analysis revealed that the body length, time of first brood, and number of neonates in the first brood of D. magna were negatively correlated with titanium accumulation in vivo. Furthermore, the indices of Ti accumulation and the product of Eg and Ti accumulation (i.e., Egâ¯×â¯Ti accumulation) were positively correlated (pâ¯<â¯0.05) with D. magna mortality, thus indicating that crystalline forms with a high Eg may cause severe toxicity to aquatic organisms at the same TiO2 bioaccumulation level.
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Nanopartículas del Metal/toxicidad , Titanio/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Correlación de Datos , Daphnia/efectos de los fármacos , Daphnia/fisiología , Humanos , Nanopartículas del Metal/química , Titanio/química , Pruebas de Toxicidad Crónica , Contaminantes Químicos del Agua/químicaRESUMEN
Titanium dioxide (TiO2) nanoparticles (NPs) encounter heavy metals in the environment under different scenarios. However, the mechanism of their joint toxicity effects on Daphnia magna remains vague. This study assessed the effects of hydrophobicity of TiO2 NPs (TDONPs) and exposure scenarios on copper uptake and toxicity in Daphnia magna. In the individual exposure scenario, hydrophilic and hydrophobic TDONPs both showed no acute toxicity to Daphnia magna, whereas individual Cu2+ exposure resulted in a 30% mortality rate. Co-exposure and sequential exposure to the two types of TDONP and Cu2+ resulted in mortality rates of 40%-50%. The mechanisms of the increased Cu2+ toxicity caused by hydrophilic and hydrophobic TDONP were different. In the presence of hydrophobic TDONPs, the Cu toxicity could be attributed to the increased bioaccumulation of Cu and Ti, leading to high oxidative stress injury. The Cu toxicity due to hydrophilic TDONPs could be induced by intensified intestinal membrane damage. The obtained data suggest that the hydrophobicity of the TDONPs plays a critical role in regulating the toxicity of Cu2+.
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Nanopartículas , Contaminantes Químicos del Agua , Animales , Cobre , Daphnia , Interacciones Hidrofóbicas e Hidrofílicas , TitanioRESUMEN
Stooping is a posture which is described as an involuntary forward bending of the thoracolumbar spine. Conventionally, the stooped posture (SP) in Parkinson's disease patients is measured in static or limited movement conditions using a radiological or optoelectronic system. In the dynamic condition with long movement distance, there was no effective method in preference to the empirical assessment from doctors. In this research, we proposed a practical method for estimating the SP with a high accuracy where accelerometers can be mounted on the neck or upper back as a wearable sensor. The experiments with simulated subjects showed a high correlation of 0.96 and 0.99 between the estimated SP angle and the reference angles for neck and back sensor position, respectively. The maximum absolute error (0.9 and 1.5 degrees) indicated that the system can be used, not only in clinical assessment as a measurement, but also in daily life as a corrector.