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A 48-year-old female patient underwent a heart transplantation for acute fulminant myocarditis, following heterologous vaccination with the ChAdOx1 nCoV-19 and Pfizer-BioNTech COVID-19. She had no history of severe acute respiratory syndrome coronavirus-2 infection. She did not exhibit clinical signs or have laboratory findings of concomitant infection before or after vaccination. Heart transplantation was performed because her heart failed to recover with venoarterial extracorporeal oxygenation support. Organ autopsy revealed giant cell myocarditis, possibly related to the vaccines. Clinicians may have to consider the possibility of the development of giant cell myocarditis, especially in patients with rapidly deteriorating cardiac function and myocarditis symptoms after COVID-19 vaccination.
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COVID-19 , Miocarditis , Vacunas contra la COVID-19/efectos adversos , ChAdOx1 nCoV-19 , Femenino , Células Gigantes , Humanos , Persona de Mediana Edad , Miocarditis/etiología , Vacunación/efectos adversosRESUMEN
Patients with cardiopulmonary failure may not be fully supported with typical configurations of extracorporeal membrane oxygenation (ECMO), either veno-arterial (VA) or veno-venous (VV). Veno-arterial-venous (VAV)-ECMO is a technique used to support the cardiopulmonary systems during periods of inadequate gas exchange and perfusion. In the severe case of coronavirus disease 2019 (COVID-19), which simultaneously affects the heart and lung, VAV-ECMO may improve a patient's recovery potential. We report the case of a 72-year-old woman with acute respiratory distress syndrome and circulatory failure following COVID-19, who was treated with VAV-ECMO.
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Betacoronavirus , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/terapia , Oxigenación por Membrana Extracorpórea/métodos , Neumonía Viral/complicaciones , Neumonía Viral/terapia , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , Anciano , COVID-19 , Cuidados Críticos/métodos , Enfermedad Crítica , Femenino , Humanos , Pandemias , SARS-CoV-2RESUMEN
High-risk human papilloma virus (HPV) 16/18 infections are often found in lung cancer. The cellular mechanisms involved in the metastatic spread of HPV-infected cervical cancer cells remain largely elusive. High O-linked-N-acetylglucosamine (O-GlcNAc) modification has also been observed in lung cancer. In the present study, we assessed the relationship between O-GlcNAc transferase (OGT) and HPV 16/18 E6/E7, or C-X-C chemokine receptor type 4 (CXCR4), in HeLa cells and in lungs of xenografted mice. Depleting OGT with an OGT-specific shRNA significantly decreased levels of E6 and E7 oncoproteins in HeLa cells and xenograft tumors, and reduced tumor formation in vivo. Western blotting and immunofluorescence analysis showed significantly decreased expression levels of E6, E7, and HCF-1 in the lungs of xenografted mice treated with an OGT-specific shRNA compared to those treated with non-targeting shRNA. Additionally, levels of E7 or OGT co-localized with Ki-67 were significantly decreased in the lungs of xenografted mice treated with OGT-specific shRNA compared to those treated with non-targeting shRNA. Moreover, levels of CXCR4 were significantly decreased in HeLa cells and in the lungs of xenografted mice treated with OGT-specific shRNA compared to those treated with non-targeting shRNA; this may be related to reduced adhesion or invasion of circulating HPV-positive tumor cells. These findings provide novel evidence that OGT functions in metastatic spread of HPV E6/E7-positive tumor cells to the lungs through E6/E7, HCF-1 and CXCR4, suggesting OGT might be a therapeutic target for HPV-positive lung cancer.
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Papillomavirus Humano 16/patogenicidad , Papillomavirus Humano 18/patogenicidad , Neoplasias Pulmonares/etiología , N-Acetilglucosaminiltransferasas/metabolismo , Infecciones por Papillomavirus/etiología , Animales , Proteínas de Unión al ADN/metabolismo , Células HeLa , Xenoinjertos , Factor C1 de la Célula Huésped/metabolismo , Humanos , Pulmón/metabolismo , Pulmón/virología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Ratones , Ratones Desnudos , N-Acetilglucosaminiltransferasas/antagonistas & inhibidores , N-Acetilglucosaminiltransferasas/genética , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Infecciones por Papillomavirus/metabolismo , Infecciones por Papillomavirus/virología , ARN Interferente Pequeño/genética , Receptores CXCR4/metabolismo , Proteínas Represoras/metabolismoRESUMEN
We report a rare case of dyspnea caused by a cardiac tumor in a 53-year-old woman. The patient had undergone a cardiac tumor (inflammatory myofibroblastic tumor, 6.2 × 4.2 × 3.3 cm) resection at our institute 13 months earlier. We performed preoperative evaluations which revealed a cardiac tumor originating from the posterior wall of the left atrium. Cardiac autotransplantation surgery (cardiac explantation, ex vivo tumor resection, cardiac reconstruction, and cardiac reimplantation) was successfully performed for the complete resection of the recurrent tumor without major postoperative complications. The patient showed good physical conditions for 21 months after the surgery. Cardiac autotransplantation is a safe and feasible technique for the complete resection of complex left atrial tumors.
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Neoplasias Cardíacas/cirugía , Trasplante de Corazón , Disnea/diagnóstico , Ecocardiografía , Femenino , Atrios Cardíacos/patología , Neoplasias Cardíacas/diagnóstico , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Tomografía Computarizada por Rayos X , Trasplante AutólogoRESUMEN
Biomaterial-based drug delivery systems have been developed to expedite cartilage regeneration; however, challenges related to drug recovery, validation, and efficient drug delivery remain. For instance, compound K (CK) is a major metabolite of ginsenosides that is known to protect against joint degeneration by inhibiting the production of inflammatory cytokines and the activation of immune cells. However, its effects on cartilage degradation and tissue regeneration remain unclear. Additionally, tissue-adhesive drug delivery depots that stably adhere to cartilage defects are required for CK delivery. In this study, CK-loaded adhesive patches were reported to seal cartilage defects and deliver CK to defect sites, preventing cartilage degradation and accelerating cartilage tissue regeneration. Adhesive patches are stable and suitable for application in surgical procedures under physiological conditions and show excellent adhesiveness to cartilage surfaces. In addition, there were no significant differences in the adhesive polymeric networks before and after CK loading. CK-loaded hydrocaffeic acid-conjugated chitosan patches significantly inhibited the stimulation of cartilage-degrading enzymes and apoptosis in osteoarthritic cartilage by releasing CK in cartilage defects. Additionally, the NFkB signaling pathway of released CK from the adhesive patches in the treatment of osteoarthritis is revealed. Thus, the CK-loaded adhesive patches are expected to significantly contribute to cartilage regeneration.
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A 63-year-old man developed chest pain and dyspnea. Venoarterial-venous extracorporeal membrane oxygenation (ECMO) was applied to the patient due to failing heart after percutaneous coronary intervention. We used an additional ECMO pump without an oxygenator for transseptal left atrial (LA) decompression and performed a heart transplant. Transseptal LA decompression with venoarterial ECMO is not always effective for severe left ventricular dysfunction. Here, we report a case of the effective use of additional ECMO pump without an oxygenator for transseptal LA decompression through controlling the blood flow rate of the transseptal LA catheter.
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Fibrilación Atrial , Oxigenación por Membrana Extracorpórea , Masculino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Oxigenadores , DescompresiónRESUMEN
Background: Patients who require initial venoarterial extracorporeal membrane oxygenation (VA ECMO) support may need to undergo veno-arteriovenous ECMO (VAV ECMO) conversion. However, there are no definitive criteria for conversion to VAV ECMO. We report 9 cases of VAV ECMO at Gyeongsang National University Changwon Hospital, Gyeongsang National University College of Medicine. Methods: Of 158 patients who received ECMO support between January 2017 and June 2019, 82 were supported by initial VA ECMO. We retrospectively reviewed the medical records of 9 patients (7 men and 2 women; age, 53.1±19.4 years) who had differential hypoxia and required VAV ECMO support. Percutaneous transaortic catheter venting was used to detect the differential hypoxia. Results: Among the 82 patients who received VA ECMO support, 9 (10.9%) had differential hypoxia and required conversion to VAV ECMO support. The mean time from VA ECMO support to VAV ECMO support and the mean duration of the VAV support were 2.1±2.2 days and 1.9±1.5 days, respectively. The average peak inspiratory pressure before and after VAV ECMO application was 23.89±3.95 cmH2O and 20.67±5.72 cmH2O, respectively, decreasing by an average of 3.2±3.5 cmH2O (p=0.040). The PaO2/FiO2 ratio was kept below 100 mm Hg in survivors and non-survivors for 116±65.4 and 250±124.9 minutes, respectively (p=0.016). Six patients underwent extracorporeal cardiopulmonary resuscitation, of whom 4 survived (67%). The overall survival rate of patients who underwent conversion from VA ECMO to VAV ECMO was approximately 56%. Conclusion: Rapid detection of differential hypoxia is required when VA ECMO is applied, and efficient conversion to VAV ECMO may be critical for patient survival.
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Hair dyeing has become a prevalent lifestyle trend, especially within the fashion industry. However, it possesses disadvantages, such as containing carcinogenic and toxic materials. In this study, we developed a biocompatible hair-dyeing technology using a shampoo with a dark polyphenol complex (DPC), referred to as S-DPC. The DPC was formed from a mixture of gallic acid and [1,1'-biphenyl]-2,2',4,4',5,5'-hexol and used to enhance both the stability of the hair coating and its ability to scavenge reactive oxygen species (ROS). Colloidal DPC particles play a pivotal role in the coating process of various hair dyes, ensuring the uniform coloring of human hair through intermolecular interactions such as hydrogen bonding. Owing to the effect of a polyphenol complex on hair coating, we observed improved antistatic performance and enhanced mechanical strength, resulting in a substantial increase in elongation at the breaking point from 33.74% to 48.85%. The multicolor S-DPC exhibited antioxidant properties, as indicated by its ROS-scavenging ability, including 2,2-diphenyl-1-picrylhydrazyl inhibition (87-89%), superoxide radical scavenging (84-87%), and hydroxyl radical scavenging (95-98%). Moreover, the in vitro analysis of the DPC revealed nearly 100% cell viability in live and dead assays, highlighting the remarkable biocompatibility of the DPC. Therefore, considering its effectiveness and safety, this biomaterial has considerable potential for applications in hair dyeing.
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Rationale: One of the hallmarks of osteoarthritis (OA), the most common degenerative joint disease, is increased numbers of senescent chondrocytes. Targeting senescent chondrocytes or signaling mechanisms leading to senescence could be a promising new therapeutic approach for OA treatment. However, understanding the key targets and links between chondrocyte senescence and OA remains unclear. Methods: Senescent chondrocytes were identified from Nudt7-/-, Acot12-/-, double-knockout mice lacking Acot12 and Nudt7 (dKO) and applied to microarray. The presence of forkhead transcription factor M1 (FOXM1) was detected in aged, dKO, and destabilization of the medial meniscus (DMM) cartilages and articular chondrocytes, and the effect of FoxM1 overexpression and acetyl-CoA treatment on cartilage homeostasis was examined using immunohistochemistry, quantitative real-time PCR (qRT-PCR), cell apoptosis and proliferation assay, and safranin O staining. Delivery of Rho@PAA-MnO2 (MnO2 nanosheet) or heparin-ACBP/COS-GA-siFoxM1 (ACBP-siFoxM1) nanoparticles into DMM cartilage was performed. Results: Here, we propose the specific capture of acetyl-CoA with the delivery of (FoxM1 siRNA (siFoxM1) to prevent cartilage degradation by inhibiting the axis of chondrocyte senescence. dKO stimulate chondrocyte senescence via the upregulation of FoxM1 and contribute to severe cartilage breakdown. We found that the accumulation of acetyl-CoA in the dKO mice may be responsible for the upregulation of FoxM1 during OA pathogenesis. Moreover, scavenging reactive oxygen species (ROS) induced by chondrocyte senescence via the implantation of MnO2 nanosheets or delivery of siFoxM1 functionalized with acetyl-CoA binding protein (ACBP) to capture acetyl-CoA using an injectable bioactive nanoparticle (siFoxM1-ACBP-NP) significantly suppressed DMM-induced cartilage destruction. Conclusion: We found that the loss of Acot12 and Nudt7 stimulates chondrocyte senescence via the upregulation of FoxM1 and accumulation of acetyl-CoA, and the application of siFoxM1-ACBP-NP is a potential therapeutic strategy for OA treatment.
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Condrocitos , Osteoartritis , Animales , Ratones , Acetilcoenzima A/metabolismo , Senescencia Celular/fisiología , Condrocitos/metabolismo , Compuestos de Manganeso/farmacología , Ratones Noqueados , Osteoartritis/metabolismo , Óxidos/farmacología , Hidrolasas NudixRESUMEN
Background: Coronary bifurcation angles influence plaque initiation in the coronary artery, and changes in blood flow caused by tortuosity in the coronary arteries can reduce blood pressure distal to the tortuous portion of the coronary artery, leading to myocardial ischemia. We aimed to describe two factors (coronary artery tortuosity and bifurcation angle) as one descriptor for the evaluation of proximal left anterior descending coronary artery (LAD) disease. Methods: We reviewed the medical records of 133 consecutive patients who underwent computed tomography angiography (CTA) for angina symptoms between November 2019 and January 2020. The patients were divided into two groups according to the presence of significant LAD stenosis on CTA (defined as LAD stenosis >50%). The straight length of the vessel was measured using the central luminal line of the flow path, and, calculated using proprietary algorithms in TeraRecon software. We used three-dimensional volume rendering and two-dimensional axial images to measure the left main coronary artery (LM)-LAD angles. Results: In the univariate analysis, there were significant differences in the linear distance between the endpoints of the 20 mm actual curve of the LAD (d20), cosine value for LM-LAD angle (cosθ) <0.8, age, presence of hypertension or diabetes, and number of pack years [hazard ratio (HR): 2.70, 8.04, 1.05, 3.70, 2.82, and 1.04; P=0.029, P<0.001, P=0.020, P=0.024, P=0.021, and P=0.002, respectively]. However, in the multivariate analysis, the cosθ multiplied by d20 (d20*cosθ) <15.5, presence of hypertension and number of pack years (HR: 11.36, 4.54, and 1.04; P<0.001, P=0.019, and P=0.003, respectively) were predictors of significant proximal LAD stenosis. Conclusions: As the tortuosity and LM-LAD angle increased (d20 and cosθ decreased, respectively), the chance of proximal LAD lesions formation increased. d20*cosθ might be useful as a predictor of proximal LAD stenosis.
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This study explored the toxic gas detection using a set of two spark-induced plasma emission spectroscopy (SIPS) modules as an alternative to conventional chemical sensors. This opens up a new possibility for detecting toxic molecules (formaldehyde, acetaldehyde, acetic acid, toluene, and ammonia) in real-time (<3 s) at relatively high sensitivity (<5 ppm). An optimized electrical controller (Raspberry Pi), manufactured as a compact and economical 3-channel optical measuring device, was developed for handling the high-resolution time-resolved electrical signals from the plasma emissions. Subsequently, the findings of this research elucidate the usability of the 3-channel SIPS device for quantitative monitoring of toxic gases.
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Contaminación del Aire Interior , Acetaldehído , Contaminación del Aire Interior/análisis , Amoníaco/análisis , Formaldehído/análisis , Gases/análisis , Análisis Espectral , ToluenoRESUMEN
Accurate identification and monitoring of fine dust are emerging as a primary global issue for addressing the harmful effects of fine dust on public health. Identifying the source of fine dust is indispensable for ensuring the human lifespan as well as preventing environmental disasters. Here a simple yet effective spark-induced plasma spectroscopy (SIPS) unit combined with deep learning for real-time classification is verified as a fast and precise PM (particulate matter) source identification technique. SIPS promises portable use, label-free detection, source identification, and chemical susceptibility in a single step with acceptable speed and accuracy. In particular, the densely connected convolutional networks (DenseNet) are used with measured spark-induced plasma emission datasets to identify PM sources at above 98%. The identification performance was compared with other common classification methods, and DenseNet with dropouts (30%), optimized batch size (16), and cyclic learning rate training emerged as the most promising source identification method.
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Contaminantes Atmosféricos , Polvo , Contaminantes Atmosféricos/análisis , Polvo/análisis , Monitoreo del Ambiente/métodos , Humanos , Material Particulado/análisis , Análisis Espectral , Emisiones de Vehículos/análisisRESUMEN
In March 2020, COVID-19 was officially classified as a pandemic and as a consequence people have adopted strenuous measures to prevent infection, such as the wearing of PPE and self-quarantining, with no knowledge of when the measures will no longer be necessary. Coronavirus has long been known to be non-infectious when airborne; however, studies are starting to show that the virus can infect through airborne transmission and can remain airborne for a significant period of time. In the present study, a spark-induced plasma spectroscopy was devised to characterize the air propagation of the virus in real-time. The risk of air propagation was evaluated in terms of changes in virus concentration with respect to distance traveled and measurement time. Thus, our study provides a benchmark for performing real-time detection of virus propagation and instantaneous monitoring of coronavirus in the air.
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COVID-19 , Humanos , Pandemias , Plasma , SARS-CoV-2 , Análisis EspectralRESUMEN
Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been widely applied to patients with cardiogenic shock. Left ventricle (LV) decompression is important when LV distension develops with pulmonary edema. The purpose of this study was to present the results of transaortic catheter venting (TACV) performed during VA-ECMO. We retrospectively reviewed the medical records of 18 patients who underwent both VA-ECMO and TACV between January 2017 and December 2019. Venoarterial extracorporeal membrane oxygenation was applied uneventfully. Lactate level and norepinephrine requirement for patients of weaning success were lower than those of patients of weaning failure after the application of TACV (p = 0.032 and p = 0.015, respectively). The successful weaning rate of ECMO was 77.8% (15/18) and survival rate was 50% (9/18). Transaortic catheter venting may be an easy, safe, and effective technique for LV decompression in patients with VA-ECMO for cardiogenic shock. Also, this technique may be helpful as an alternative or bridge method.
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Oxigenación por Membrana Extracorpórea , Catéteres , Descompresión , Oxigenación por Membrana Extracorpórea/efectos adversos , Ventrículos Cardíacos/cirugía , Humanos , Estudios Retrospectivos , Choque Cardiogénico/etiología , Choque Cardiogénico/cirugíaRESUMEN
A 34-year-old man developed severe hypoxemia and hypercapnia due to acute respiratory distress during ventilator care after surgery with acute intracranial hemorrhage. Severe hypoxemia had not been corrected even with maximum extracorporeal membrane oxygenation (ECMO) flow and full ventilator settings. We applied a novel technique for the serial connection of two veno-venous ECMO circuits for optimal oxygen delivery and CO2 removal and could wean VV ECMO. The use of serial connection of two VV ECMO circuits may be considered worthwhile when severe hypoxemia or hypercapnia are not improved and the use of protective ventilators is not permitted.
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Oxigenación por Membrana Extracorpórea , Síndrome de Dificultad Respiratoria , Adulto , Humanos , Hipoxia/etiología , Masculino , Oxigenadores de Membrana , Ventiladores MecánicosRESUMEN
A growing modern-day concern is fine dust air pollution that contains heavy metals and ammonium ions (NH4+) from industrial and agricultural waste sources, respectively. In the current study, the development of an innovative and effective technique for real-time, quantitative monitoring of toxic fine dust components using plasma emission spectroscopy is presented as a complement to emergency preparedness plans aimed at reducing dust pollution. A novel spark-induced plasma spectroscopic (SIPS) device that can control the frequency and magnitude of plasma was developed for the toxic pollutants in this work. SIPS utilizes an electrical discharge from a high voltage at a low current to produce plasma when the applied voltage is higher than the ambient voltage surrounding the electrodes. The detection limit of this setup was enhanced by a factor of 4.3 over laser-induced plasma spectroscopy (LIPS). This compact sensing device was used in combination with a new quantitative analytical method to measure the concentration of heavy metals and ammonia molecules in fine dust air pollution. By integrating the time-resolved plasma emission signals that were based on the plasma continuum decay time of each element, quantitative measurements of the minute changes in composition of 0.1 µg/m3 were conducted. The findings of this study could inspire future research on the use of SIPS for monitoring airborne fine dust pollutants with better sensitivity in real-time via a new quantitative analytical method.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Contaminación del Aire/análisis , Polvo/análisis , Contaminantes Ambientales , Industrias , Metales Pesados/análisis , Análisis EspectralRESUMEN
RATIONALE: The preoperative diagnosis of massive pulmonary tumor embolism associated with renal neoplasms is relatively rare. In most cases, pulmonary tumor embolism is detected intraoperatively during renal tumor resection. Moreover, primary renal sarcoma is rare, and primary renal sarcoma complicated by pulmonary tumor embolism is extremely rare; accordingly, there is no optimal treatment for such cases. Herein, we report a case of renal sarcoma associated with pulmonary tumor embolism. PATIENT CONCERNS: A 39-year-old man was admitted to the emergency room owing to the sudden onset of dyspnea and palpitation. DIAGNOSIS: Contrast-enhanced computed tomography (CT) revealed a large mass in the right kidney involving the infrahepatic inferior vena cava, with massive pulmonary emboli in both the pulmonary arteries. INTERVENTIONS: Emergency pulmonary embolectomy with radical nephrectomy was performed. OUTCOMES: The patient experienced apparent remission of dyspnea, and resolution of right ventricle dysfunction. However, although remnant emboli were detected in the segmental arteries on postoperative CT, complete resolution of pulmonary embolism was observed after adjuvant chemotherapy. LESSONS: Thus, concomitant cytoreductive nephrectomy with pulmonary embolectomy along with chemotherapy may be effective for patients with renal sarcoma with pulmonary tumor embolism.
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Neoplasias Renales/complicaciones , Neoplasias Pulmonares/complicaciones , Embolia Pulmonar/etiología , Sarcoma/complicaciones , Adulto , Embolectomía/métodos , Humanos , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/cirugía , Masculino , Nefrectomía/métodos , Arteria Pulmonar/patología , Embolia Pulmonar/patología , Embolia Pulmonar/cirugía , Sarcoma/secundario , Sarcoma/cirugía , Vena Cava Inferior/patologíaRESUMEN
BACKGROUND: Secondary spontaneous pneumothorax is generally managed by surgery, if pneumothorax was not improved following chest tube insertion or in the event of persistent air leakage lasting more than 5 days. However, if surgery is not an option, chemical pleurodesis with sclerosants can be performed. Several sclerosants have been used in the chemical pleurodesis of secondary spontaneous pneumothorax, However, there is still controversy for what is the ideal sclerosant for Secondary spontaneous pneumothorax. The use of Viscum album L. for chemical pleurodesis in patients with secondary spontaneous pneumothorax aged >65 years has not been described to date, despite its extensive use. The authors tried to find out the effect of Viscum album L. for sclerosant for Secondary spontaneous pneumothorax in elder. METHODS: This retrospective analysis examined 25 patients (aged >65 years) with secondary spontaneous pneumothorax with persistent air leakage who underwent chemical pleurodesis with Abnova Viscum-F® (V. album L.). RESULTS: The duration of chest tube drainage was 5.08 days after chemical pleurodesis. Adverse effects related to chemical pleurodesis with Abnova Viscum-F® were fever (7/25), pain (4/25), leukocytosis (10/25), and dyspnea with desaturation (7/25); however all the patients recovered without sequela and were subsequently discharged. CONCLUSIONS: The present study demonstrated the successful use of chemical pleurodesis with V. album L. in the management of elderly patients with secondary spontaneous pneumothorax. Because of the high probability of dyspnea with desaturation in the elderly, caution must be exercised.
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The degradation of thermal properties due to ageing such as burning rate and exothermic heat release are unsolved issues faced during a long-term storage of the pyrotechnic substances. Accordingly, we employed various non-calorimetric methods to investigate the thermal performance of pyrotechnic delay, which is exposed to various moisture-rich conditions at extended durations. The chemical and physical changes in the compositions of a pyrotechnic delay comprised of metal fuel (Zr-Ni alloy) and oxidants (KClO4, BaCrO4) are analysed for four different relative humidity levels using X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscope and laser-induced breakdown spectroscopy. The calculations using the NASA Chemical Equilibrium with Applications (CEA) software indicated that the heat of reaction for the components stored under the moisture-rich conditions is reduced by more than 50%. Unlike the conventional calorimetric analysis, the present non-calorimetric approach provided the compositional changes as well as the cause and effect of the relevant ageing process of pyrotechnic delay.
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Chest computed tomography demonstrated a suspected primary tumor in the upper sternal body of a 48-year-old woman who presented with sternal pain. After being diagnosed with chondrosarcoma, she underwent sternal resection. Subsequent chest wall reconstruction was performed after careful planning using a bone cement block made of polypropylene mesh and polymethylmethacrylate. The block was fixed to the manubrium and ribs using the SternaLock System. She was discharged following an uneventful postoperative recovery, and is currently undergoing follow-up.