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1.
Rinsho Ketsueki ; 65(2): 63-68, 2024.
Artigo em Japonês | MEDLINE | ID: mdl-38447999

RESUMO

A 28-year-old man was diagnosed with acute myelomonocytic leukemia. He achieved complete remission (CR) after two cycles of induction therapy. However, after consolidation therapy, bone marrow aspiration performed to prepare for allogeneic hematopoietic stem cell transplantation revealed disease relapse. Companion diagnostics confirmed the presence of the FLT3-ITD mutation. The patient received gilteritinib monotherapy and achieved CR. Subsequently, he underwent unrelated allogeneic bone marrow transplantation. One year after transplantation, the patient relapsed, and gilteritinib was resumed. However, the leukemia progressed, and panel sequencing using a next-generation sequencer showed that the FLT3-ITD mutation disappeared. A mutation in PTPN11, which regulates the RAS/MAPK signaling pathway, was also detected. Gilteritinib was discontinued, and the patient achieved CR with salvage chemotherapy. He underwent related haploidentical peripheral blood stem cell transplantation but died of relapse. This was a case in which genetic analysis revealed clonal transition and acquisition of resistance to treatment.


Assuntos
Leucemia Mieloide Aguda , Masculino , Humanos , Adulto , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Compostos de Anilina , Pirazinas , Doença Crônica , Mutação , 60410 , Tirosina Quinase 3 Semelhante a fms/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética
2.
Rinsho Ketsueki ; 65(2): 84-89, 2024.
Artigo em Japonês | MEDLINE | ID: mdl-38448003

RESUMO

A 63-year-old man with adult T-cell leukemia-lymphoma underwent allogeneic bone marrow transplantation from an HLA-matched unrelated donor. On day 17 after transplantation, chest computed tomography (CT) showed nodules in the lower lobes of both lungs, and invasive pulmonary aspergillosis (IPA) was suspected. Treatment with liposomal amphotericin B was started, and improvement of infectious lesions was confirmed with CT on day 28. The antifungal agent was changed to voriconazole on day 52 because of progressive renal dysfunction. Disorders of consciousness and paralysis of the left upper and lower extremities developed on day 61. Brain CT showed subcortical hemorrhage in the right parietal and occipital lobes, and the patient died on day 62. An autopsy revealed filamentous fungi, suspected to be Aspergillus, in the pulmonary nodules and a ruptured cerebral aneurysm. Although IPA occurs in 10% of transplant recipients, vigilant monitoring for mycotic cerebral aneurysms is required to prevent hematogenous dissemination of Aspergillus, which is associated with a high mortality rate.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Aneurisma Intracraniano , Leucemia-Linfoma de Células T do Adulto , Linfoma , Adulto , Masculino , Humanos , Pessoa de Meia-Idade , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/terapia , Leucemia-Linfoma de Células T do Adulto/complicações , Leucemia-Linfoma de Células T do Adulto/terapia , Transplante de Medula Óssea
3.
FEBS Open Bio ; 14(4): 598-612, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38373743

RESUMO

The Egyptian Rousettus bat (Rousettus aegyptiacus) is a common fruit bat species that is distributed mainly in Africa and the Middle East. Bats serve as reservoir hosts for numerous pathogens. Human activities, such as hunting bats for food, managing vermin, and causing habitat loss, elevate the likelihood of transmission of bat pathogens to humans and other animals. Consequently, bat cell lines play a crucial role as research materials for investigating viral pathogens. However, the inherent limitation of finite cell division in primary cells necessitates the use of immortalized cells derived from various bat tissues. Herein, we successfully established six fibroblast cell lines derived from an infant bat heart and lungs and an elderly bat heart. Three of the six cell lines, called K4DT cells, were transduced by a combination of cell cycle regulators, mutant cyclin-dependent kinase 4, cyclin D1, and human telomerase reverse transcriptase. The other three cell lines, named SV40 cells, were transfected with simian virus 40 large T antigen. Transgene protein expression was detected in the transduced cells. All three K4DT cell lines and one lung-derived SV40 cell line were virtually immortalized and nearly maintained the normal diploid karyotypes. However, the two other heart-derived SV40 cell lines had aberrant karyotypes and the young bat-derived cell line stopped proliferating at approximately 40 population doublings. These bat cell lines are valuable for studying pathogen genomics and biology.


Assuntos
Quirópteros , Animais , Humanos , Idoso , Egito , Linhagem Celular
4.
Microbiol Spectr ; 12(4): e0285923, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38415690

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) utilizes several host proteases to cleave the spike (S) protein to enter host cells. SARS-CoV-2 S protein is cleaved into S1 and S2 subunits by furin, which is closely involved in the pathogenicity of SARS-CoV-2. However, the effects of the modulated protease cleavage activity due to S protein mutations on viral replication and pathogenesis remain unclear. Herein, we serially passaged two SARS-CoV-2 strains in Vero cells and characterized the cell-adapted SARS-CoV-2 strains in vitro and in vivo. The adapted strains showed high viral growth, effective S1/S2 cleavage of the S protein, and low pathogenicity compared with the wild-type strain. Furthermore, the viral growth and S1/S2 cleavage were enhanced by the combination of the Δ68-76 and H655Y mutations using recombinant SARS-CoV-2 strains generated by the circular polymerase extension reaction. The recombinant SARS-CoV-2 strain, which contained the mutation of the adapted strain, showed increased susceptibility to the furin inhibitor, suggesting that the adapted SARS-CoV-2 strain utilized furin more effectively than the wild-type strain. Pathogenicity was attenuated by infection with effectively cleaved recombinant SARS-CoV-2 strains, suggesting that the excessive cleavage of the S proteins decreases virulence. Finally, the high-growth-adapted SARS-CoV-2 strain could be used as the seed for a low-cost inactivated vaccine; immunization with this vaccine can effectively protect the host from SARS-CoV-2 variants. Our findings provide novel insights into the growth and pathogenicity of SARS-CoV-2 in the evolution of cell-cell transmission. IMPORTANCE: The efficacy of the S protein cleavage generally differs among the SARS-CoV-2 variants, resulting in distinct viral characteristics. The relationship between a mutation and the entry of SARS-CoV-2 into host cells remains unclear. In this study, we analyzed the sequence of high-growth Vero cell-adapted SARS-CoV-2 and factors determining the enhancement of the growth of the adapted virus and confirmed the characteristics of the adapted strain by analyzing the recombinant SARS-CoV-2 strain. We successfully identified mutations Δ68-76 and H655Y, which enhance viral growth and the S protein cleavage by furin. Using recombinant viruses enabled us to conduct a virus challenge experiment in vivo. The pathogenicity of SARS-CoV-2 introduced with the mutations Δ68-76, H655Y, P812L, and Q853L was attenuated in hamsters, indicating the possibility of the attenuation of excessive cleaved SARS-CoV-2. These findings provide novel insights into the infectivity and pathogenesis of SARS-CoV-2 strains, thereby significantly contributing to the field of virology.


Assuntos
COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Chlorocebus aethiops , Humanos , Células Vero , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Furina/metabolismo
5.
Rinsho Ketsueki ; 65(1): 7-12, 2024.
Artigo em Japonês | MEDLINE | ID: mdl-38311391

RESUMO

An 18-year-old man underwent allogenic bone marrow transplantation (BMT) for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL). Ph+ALL relapsed 3 months after the first BMT, and the patient underwent a second BMT. However, Ph+ALL relapsed 4 months after the second BMT, and he received a haploidentical peripheral blood stem cell transplantation (haplo-PBSCT) from his father. Molecular complete remission was confirmed 29 days after haplo-PBSCT. However, the patient needed dialysis for end-stage renal disease due to thrombotic microangiopathy 3 years and 2 months after haplo-PBSCT. He received a kidney transplantation from his father 7 years and 10 months after haplo-PBSCT, and got off dialysis after the kidney transplantation. Immunosuppressive therapy with methylprednisolone, tacrolimus, and mycophenolate mofetil was started for kidney transplantation, but the dose of immunosuppressive agents was reduced successfully without rejection soon after kidney transplantation. The patient has maintained long-term remission since the haplo-PBSCT, and his kidney function was restored by the kidney transplantation from his father.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Falência Renal Crônica , Transplante de Rim , Leucemia-Linfoma Linfoblástico de Células Precursoras , Masculino , Humanos , Adolescente , Cromossomo Filadélfia , Transplante Homólogo , Transplante de Medula Óssea , Doença Aguda , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia
6.
IEEE Trans Haptics ; 17(1): 8-13, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38190670

RESUMO

This study aims to represent fine texture differences in pencil hardness using intensity segment modulation (ISM), a sensory equivalent conversion method of vibration from high to low frequencies. This method enables the presentation of delicate tactile sensations even with small transducers. We integrated this approach in the world's thinnest ultra-thin PZT-MEMS vibrator with a stylus-type device. The vibration waveforms of four types of pencil hardness were captured under the same conditions, and the differences in the frequency components were confirmed. We compared the fine texture feelings under raw signal, ISM, and ISM below 1 kHz conditions by conducting discrimination tests and subjective similarity evaluations. The results showed that ISM could reproduce similar feelings of the pencil hardness.


Assuntos
Sistemas Microeletromecânicos , Percepção do Tato , Humanos , Dureza , Tato , Vibração
7.
IEEE Trans Haptics ; 17(1): 20-25, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38227399

RESUMO

Thin and light vibrators that leverage the inverse piezoelectric effect with a diaphragm mechanism are promising vibrotactile actuators owing to their form factors and high temporal and frequency response. However, generating perceptually sufficient displacement in the low-frequency domain is challenging. This study presents a lever mechanism mounted on a diaphragm vibrator to enhance the vibrotactile intensity of low-frequency vibrotactile stimuli. The lever mechanism is inspired by the tactile contact lens consisting of an array of cylinders held against the skin on a sheet that enhances micro-bump tactile detection. We built an experimental apparatus including our previously developed thin-film diaphragm-type vibrator, which reproduced the common characteristic of piezoelectric vibrators: near-threshold displacement (10 to 20 µm) at low frequency. Experiments demonstrated enhanced vibrotactile intensity at frequencies less than 100 Hz with the lever mechanism. Although the arrangement and material of the mechanism can be improved, our findings can help improve the expressiveness of diaphragm-type vibrators.


Assuntos
Percepção do Tato , Humanos , Diafragma , Tato/fisiologia , Pele , Vibração
9.
Nutrition ; 120: 112330, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38262195

RESUMO

OBJECTIVES: Phase angle (PhA) reflects cell membrane integrity and vitality and is an indicator of sarcopenia. PhA is associated with physical function in patients with stable chronic obstructive pulmonary disease (COPD). To our knowledge, the association between PhA and physical activity (PA) has not been investigated. Therefore, the aim of this study was to investigate whether PhA reflects PA in patients with COPD. METHODS: This single-center, cross-sectional, observational study included 103 patients with stable COPD (87 men; mean age, 74.7 ± 8.1 y; mean forced expiratory volume in 1s %predicted value, 58.9 ± 20.4%). PhA was measured by bioelectrical impedance analysis. Patients were stratified into low (n = 54) and high (n = 49) PhA groups based on median values (4.3° ± 0.6° and 5.4° ± 0.5°, respectively). PA was calculated as the average daily duration of high-intensity light PA (HLPA; 2.0-2.9 metabolic equivalents [METs] of PA) and moderate- to vigorous-intensity PA (MVPA; >3 METs). Correlation and multivariate analyses using multiple regression analysis were performed to confirm the association between PhA and PA. RESULTS: The high-PhA group demonstrated greater HLPA (104.4 [16.5-332.5] versus 131.3 [61.1-328.7] min, P = 0.005) and MVPA (19.5 [4.7-96.0] versus 46.6 [8.9-139.3] min, P < 0.001) than the low-PhA group. PhA was positively correlated with HLPA (r = 0.32, P < 0.001) and MVPA (r = 0.49, P < 0.001). MVPA (ß = 0.178, P = 0.029) and HLPA (ß = 0.158, P = 0.026) were associated with PhA independent of age, sex, body mass index, respiratory function, muscle strength, skeletal muscle mass index, and 6-min walking distance. CONCLUSION: In patients with COPD, PhA may reflect PA as well as muscle function.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Sarcopenia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Estudos Transversais , Impedância Elétrica , Exercício Físico , Força Muscular/fisiologia , Sarcopenia/etiologia , Feminino
10.
Pharmaceuticals (Basel) ; 17(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38256912

RESUMO

The outcomes of unresectable gastric cancer (GC) are unfavorable even with chemotherapy; therefore, a new treatment modality is required. The combination of an oncolytic virus and photodynamic therapy can be one of the promising modalities to overcome this. Mammalian orthoreovirus (MRV) is an oncolytic virus that has been used in clinical trials for several cancers. In this study, we developed and evaluated a recombinant MRV strain type 3 Dearing (T3D) that expresses membrane-targeting KillerRed (KRmem), a phototoxic fluorescent protein that produces cytotoxic reactive oxygen species upon light irradiation. KRmem was fused in-frame to the 3' end of the σ2 viral gene in the S2 segment using a 2A peptide linker, enabling the expression of multiple proteins from a single transcript. RNA electrophoresis, Western blotting, and immunofluorescence analyses confirmed functional insertion of KRmem into the recombinant virus. The growth activity of the recombinant virus was comparable to that of the wild-type MRV in a cultured cell line. The recombinant virus infected two GC cell lines (MKN45P and MKN7), and a significant cytocidal effect was observed in MKN45P cells infected with the recombinant virus after light irradiation. Thus, recombinant MRV-expressing KRmem has the potential to serve as a novel treatment tool for GC.

11.
J Thorac Oncol ; 19(1): 94-105, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37595684

RESUMO

INTRODUCTION: With global adoption of computed tomography (CT) lung cancer screening, there is increasing interest to use artificial intelligence (AI) deep learning methods to improve the clinical management process. To enable AI research using an open-source, cloud-based, globally distributed, screening CT imaging data set and computational environment that are compliant with the most stringent international privacy regulations that also protect the intellectual properties of researchers, the International Association for the Study of Lung Cancer sponsored development of the Early Lung Imaging Confederation (ELIC) resource in 2018. The objective of this report is to describe the updated capabilities of ELIC and illustrate how this resource can be used for clinically relevant AI research. METHODS: In this second phase of the initiative, metadata and screening CT scans from two time points were collected from 100 screening participants in seven countries. An automated deep learning AI lung segmentation algorithm, automated quantitative emphysema metrics, and a quantitative lung nodule volume measurement algorithm were run on these scans. RESULTS: A total of 1394 CTs were collected from 697 participants. The LAV950 quantitative emphysema metric was found to be potentially useful in distinguishing lung cancer from benign cases using a combined slice thickness more than or equal to 2.5 mm. Lung nodule volume change measurements had better sensitivity and specificity for classifying malignant from benign lung nodules when applied to solid lung nodules from high-quality CT scans. CONCLUSIONS: These initial experiments revealed that ELIC can support deep learning AI and quantitative imaging analyses on diverse and globally distributed cloud-based data sets.


Assuntos
Aprendizado Profundo , Enfisema , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Inteligência Artificial , Detecção Precoce de Câncer , Pulmão/patologia , Enfisema/patologia
12.
Ann Hematol ; 103(1): 285-296, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37947825

RESUMO

Cytomegalovirus (CMV) infection is a major infectious complication following allogeneic hematopoietic cell transplantation (allo-HCT). Although letermovir (LMV) prophylaxis dramatically reduces the incidence of early clinically significant CMV (csCMV) infection, it remains unclear whether it has a beneficial effect on nonrelapse mortality (NRM) and overall survival (OS). Herein, we evaluated the impact of LMV prophylaxis on posttransplant outcomes using the registry database of the Japanese Society for Transplantation and Cellular Therapy. Adult patients who underwent allo-HCT between 2017 and 2019 were analyzed (n = 6004). LMV prophylaxis was administered to 1640 patients (LMV group) and it significantly reduced the incidence of csCMV infection compared with those not administered LMV prophylaxis (15.4% vs 54.1%; p < 0.01). However, it did not improve the 1-year NRM (hazard ratio [HR], 0.93; p = 0.40) and OS (HR, 0.96; p = 0.49). In the LMV group, 74 patients had breakthrough csCMV infection and showed inferior NRM (HR, 3.44; p < 0.01) and OS (HR, 1.93; p = 0.02) compared with those without infection. After completing LMV prophylaxis, 252 patients had late csCMV infection and showed inferior NRM (HR, 1.83; p < 0.01) and OS (HR, 1.58; p < 0.01). Our findings suggest that managing breakthrough and late csCMV infections is important for improving long-term outcomes.


Assuntos
Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Citomegalovirus , Antivirais/uso terapêutico , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Estudos Retrospectivos
13.
Jpn J Radiol ; 42(3): 291-299, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38032419

RESUMO

PURPOSE: This study aimed to evaluate the performance of the commercially available artificial intelligence-based software CXR-AID for the automatic detection of pulmonary nodules on the chest radiographs of patients suspected of having lung cancer. MATERIALS AND METHODS: This retrospective study included 399 patients with clinically suspected lung cancer who underwent CT and chest radiography within 1 month between June 2020 and May 2022. The candidate areas on chest radiographs identified by CXR-AID were categorized into target (properly detected areas) and non-target (improperly detected areas) areas. The non-target areas were further divided into non-target normal areas (false positives for normal structures) and non-target abnormal areas. The visibility score, characteristics and location of the nodules, presence of overlapping structures, and background lung score and presence of pulmonary disease were manually evaluated and compared between the nodules detected or undetected by CXR-AID. The probability indices calculated by CXR-AID were compared between the target and non-target areas. RESULTS: Among the 450 nodules detected in 399 patients, 331 nodules detected in 313 patients were visible on chest radiographs during manual evaluation. CXR-AID detected 264 of these 331 nodules with a sensitivity of 0.80. The detection sensitivity increased significantly with the visibility score. No significant correlation was observed between the background lung score and sensitivity. The non-target area per image was 0.85, and the probability index of the non-target area was lower than that of the target area. The non-target normal area per image was 0.24. Larger and more solid nodules exhibited higher sensitivities, while nodules with overlapping structures demonstrated lower detection sensitivities. CONCLUSION: The nodule detection sensitivity of CXR-AID on chest radiographs was 0.80, and the non-target and non-target normal areas per image were 0.85 and 0.24, respectively. Larger, solid nodules without overlapping structures were detected more readily by CXR-AID.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Inteligência Artificial , Estudos Retrospectivos , Radiografia Torácica/métodos , Pulmão , Software , Radiografia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Sensibilidade e Especificidade
14.
Transplant Cell Ther ; 30(1): 121.e1-121.e8, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37813188

RESUMO

Several recent studies have demonstrated that urinary levels of liver-type fatty acid-binding protein (L-FABP) can be used to stratify the prognosis of cardiac disease, cardiac intensive care unit admission, cirrhosis, and coronavirus disease 2019. Our initial prospective study revealed that urinary L-FABP (uL-FABP) was associated with a high probability of acute kidney injury after stem cell transplantation (SCT); however, the relevance of elevated uL-FABP to the prognosis of patients undergoing SCT remains to be determined. We aimed to investigate whether uL-FABP levels can be used to stratify patient prognosis after SCT. To achieve this aim, we conducted a new long-term follow-up study using data from patients enrolled in our preceding prospective cohort study. Patients were classified into high and low uL-FABP groups based on levels measured at baseline (ie, before initiating the conditioning regimen), using an uL-FABP cutoff of 8.4 µg/gCr, which was determined based on data from healthy adults. uL-FABP levels were also measured on days 0, 7, and 14 after SCT. Cox proportional hazard regression was used to examine the effects of each factor on survival outcomes, and Fine-Gray regression was used in the presence of competing risks. Multivariate analysis incorporating confounders was then performed for factors with P < .1 in univariate analysis. In total, 20 of 84 patients (23.8%), 57 of 84 patients (67.9%), 34 of 49 patients (69.4%), and 34 of 46 patients (73.9%) were classified into the high uL-FABP group at baseline and on days 0, 7, and 14, respectively. The 5-year overall survival (OS) rate was 23.9% in the high uL-FABP group and 68.9% in the low uL-FABP group. The multivariate analysis identified a high uL-FABP level at baseline as a significant prognostic factor for poor OS (hazard ratio [HR], 3.54; P = .002). The 5-year cumulative incidence rate for nonrelapse mortality (NRM) was 50.0% in the high uL-FABP group and 19.9% in the low uL-FABP group. In the multivariate analysis, high uL-FABP at baseline was a significant prognostic factor for NRM (HR, 3.37; P = .01). uL-FABP levels did not significantly stratify the cumulative incidence of relapse (HR, 2.13; P = .11). uL-FABP levels on days 0, 7, and 14 were not significant predictors of survival. High uL-FABP level before initiation of conditioning significantly influences OS and NRM following SCT, whereas a high uL-FABP level at any point after the conditioning regimen does not. Our results show that measuring uL-FABP level at baseline may be a simple way to predict survival in patients undergoing SCT.


Assuntos
Proteínas de Ligação a Ácido Graxo , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Estudos Prospectivos , Seguimentos , Biomarcadores/urina , Prognóstico , Proteínas de Ligação a Ácido Graxo/urina , Transplante de Células-Tronco , Fígado
15.
Soft Matter ; 20(3): 523-534, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38116791

RESUMO

Predicting the behaviour of solutions with surfactants of significantly different critical micelle concentration (CMC) values remains a challenge. The study of the molecular interactions within micelles and interfaces in surfactant combinations used in everyday products is essential to understand these complex systems. In this work, the equilibrium and dynamic surface tension in the presence of mixed non-ionic (tristyrylphenol ethoxylates) and anionic (sodium benzene sulfonate with alkyl chain lengths of C10-C13) surfactants, commonly encountered as delivery systems in agrochemicals, were studied and their CMC values were determined. For the surfactant mixtures, four molar ratios were examined: nEOT/nNaDDBS = 0.01, 0.1, 1, 4 and two different cases were analysed, the premixed and the add one by one surfactant. The surface tension for single surfactants stabilised quickly, while the mixtures needed a long time to reach equilibrium; up to 15 h for the premixed mixtures and 40 min when surfactants were added one by one. The CMC values for the nEOT/nNaDDBS = 0.01, 0.1 premixed surfactant mixtures were found to be in between the CMC values of the single surfactants, but those for the nEOT/nNaDDBS = 1 and 4 mixtures were lower than the CMCs of both single surfactants. Calculations based on the regular solution theory suggested that there are attractive forces in the mixed micelles and at the interface layers, while the supramolecular assemblies in the bulk (i.e., micelles) and at interfaces (surfactant films) are preferentially enriched in EOT.

16.
J Oleo Sci ; 72(11): 1005-1014, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37914262

RESUMO

The acute aquatic toxicity of anionic surfactants, including fatty acid salts, changes depending on water hardness. Generally, the acute aquatic toxicity of Daphnia magna is caused by the adsorption of surfactants and other substances. Despite the low environmental risk, the effect of water hardness on the acute aquatic toxicity of soap should be discussed to improve the assessment accuracy. Previously, we evaluated the effects of water hardness and the presence of an adsorbent on the acute aquatic toxicity of soap by performing an immobility test using D. magna in accordance with Japanese Industrial Standards (JIS) K 0229. Immobility was low at 50 ppm and a higher water hardness was indicated owing to the loss of interfacial activities caused by the formation of insoluble fatty acid calcium or magnesium complexes (soap scum). In the current study, we evaluate the effects of water hardness on the acute aquatic toxicity of C10, C12, C14, C16, and C18 saturated and C18:1 unsaturated fatty acid sodium salts. The EC50 is measured via an immobility test in accordance with JIS K 0229 using D. magna, and the surface tension is measured as an indicator of surface activity. Results show that the EC50 and surface tension curves change with water hardness in single and mixed solutions. C18:1 indicates the least change and the highest surface activity. Moreover, immobility change is not observed when C18:1 is filtered, whereas the immobility of other solutions decreased significantly. This implies the effect of soap scum on immobility, such as the clogging of gills by soap scum. Based on quantitative analysis, the percentage of C18:1 that transformed soap scum to its initial concentration exceeds 80%. This implies that calcium deficiency under 5 and 25 ppm water hardness affects the immobility of larval D. magna. The effects of soap scum clogging and calcium deficiency on D. magna should be considered before assessing the soap.


Assuntos
Poluentes Químicos da Água , Água , Animais , Cálcio/análise , Sais/toxicidade , Dureza , Sabões/análise , Ácidos Graxos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
17.
Angew Chem Int Ed Engl ; 62(50): e202312546, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37948306

RESUMO

The novel electrophilic organo-tantalum catalyst AlS/TaNpx (1) (Np=neopentyl) is prepared by chemisorption of the alkylidene Np3 Ta=CHt Bu onto highly Brønsted acidic sulfated alumina (AlS). The proposed catalyst structure is supported by EXAFS, XANES, ICP, DRIFTS, elemental analysis, and SSNMR measurements and is in good agreement with DFT analysis. Catalyst 1 is highly effective for the hydrogenolysis of diverse linear and branched hydrocarbons, ranging from C2 to polyolefins. To the best of our knowledge, 1 exhibits one of the highest polyolefin hydrogenolysis activities (9,800 (CH2 units) ⋅ mol(Ta)-1 ⋅ h-1 at 200 °C/17 atm H2 ) reported to date in the peer-reviewed literature. Unlike the AlS/ZrNp2 analog, the Ta catalyst is more thermally stable and offers multiple potential C-C bond activation pathways. For hydrogenolysis, AlS/TaNpx is effective for a wide variety of pre- and post-consumer polyolefin plastics and is not significantly deactivated by standard polyolefin additives at typical industrial concentrations.

18.
Front Microbiol ; 14: 1284274, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928667

RESUMO

It is essential to employ efficient measures to prevent the transmission of pathogenic agents during a pandemic. One such method involves using hypochlorous acid (HClO) solution. The oxidative properties of HClO water (HAW) can contribute to its ability to eliminate viral particles. Here, we examined a highly purified slightly acidic hypochlorous acid water (Hp-SA-HAW) obtained from the reverse osmosis membrane treatment of an electrolytically-generated SA-HAW for its anti-viral activity and mode of action on viral proteins. Hp-SA-HAW exhibited broad-spectrum antiviral effects against various viruses, including adenovirus, hepatitis B virus, Japanese encephalitis virus (JEV), and rotavirus. Additionally, Hp-SA-HAW treatment dose-dependently resulted in irreversibly aggregated multimers of the JEV envelope and capsid proteins. However, Hp-SA-HAW treatment had no discernible effect on viral RNA, indicating that Hp-SA-HAW acts against amino acids rather than nucleic acids. Furthermore, Hp-SA-HAW substantially reduced the infectivity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including the ancestral variant and other multiple variants. Hp-SA-HAW treatment induced the aggregation of the SARS-CoV-2 spike and nuclear proteins and disrupted the binding of the purified spike protein of SARS-CoV-2 to human ACE2. This study demonstrates that the broad-spectrum virucidal activity of highly purified HClO is attributed to viral protein aggregation of virion via protein oxidation.

19.
ACS Appl Mater Interfaces ; 15(46): 54192-54201, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37934618

RESUMO

We studied the mechanism underlying the solid-phase adsorption of a heavy rare-earth element (HREE, Yb) from acidic solutions employing MCM-22 zeolite, serving as both a layered synthetic clay mimic and a new platform for the mechanistic study of HREE adsorption on aluminosilicate materials. Mechanistic studies revealed that the adsorption of Yb(III) at the surface adsorption site occurs primarily through the electrostatic interaction between the site and Yb(III) species. The dependence of Yb adsorption on the pH of the solution indicated the role of surface charge, and the content of framework Al suggested that the Brønsted acid sites (BAS) are involved in the adsorption of Yb(III) ions, which was further scrutinized by spectroscopic analysis and theoretical calculations. Our findings have illuminated the roles of surface sites in the solid-phase adsorption of HREEs from acidic solutions.

20.
J Chem Theory Comput ; 19(20): 7371-7386, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37815387

RESUMO

This paper presents a novel approach to predicting critical micelle concentrations (CMCs) by using graph neural networks (GNNs) augmented with Gaussian processes (GPs). The proposed model uses learned latent space representations of molecules to predict CMCs and estimate uncertainties. The performance of the model on a data set containing nonionic, cationic, anionic, and zwitterionic molecules is compared against a linear model that works with extended connectivity fingerprints (ECFPs). The GNN-based model performs slightly better than the linear ECFP model when there is enough well-balanced training data and achieves predictive accuracy that is comparable to published models that were evaluated on a smaller range of surfactant chemistries. We illustrate the applicability domain of our model using a molecular cartogram to visualize the latent space, which helps to identify molecules for which predictions are likely to be erroneous. In addition to accurately predicting CMCs for some surfactant classes, the proposed approach can provide valuable insights into the molecular properties that influence CMCs.

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