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BACKGROUND: The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been followed by many reports of the development and relapse of autoimmune diseases associated with SARS-CoV-2 vaccination. Some of these reports have involved relapse or onset of immunoglobulin A (IgA) nephropathy following SARS-CoV-2 vaccination. Here, we report on a patient with IgA nephropathy who presented with gross hematuria and rapidly progressive glomerulonephritis following SARS-CoV-2 vaccination. CASE PRESENTATION: A 63-year-old male patient with a history of habitual tonsillitis underwent bilateral tonsillectomy. He had a history of alcoholic cirrhosis of the liver and microscopic hematuria and proteinuria were indicated during a health checkup 2 years before hospital admission. He developed hematuria after the SARS-CoV-2 vaccination, which led to rapidly progressive glomerulonephritis, for which he was hospitalized. A renal biopsy led to the diagnosis of IgA nephropathy. Although pulse steroid therapy during his condition resulted in hepatic encephalopathy, three courses combined with mizoribine improved his renal function. CONCLUSION: SARS-CoV-2 mRNA vaccines activate T cells, which are involved in the pathophysiology of IgA nephropathy. Therefore, this case suggests that the exacerbation of IgA nephropathy by the vaccine favors the vasculitis aspect of the disease.
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COVID-19 , Glomerulonefrite por IGA , Glomerulonefrite , Nefrite , Masculino , Humanos , Pessoa de Meia-Idade , Glomerulonefrite por IGA/diagnóstico , SARS-CoV-2 , Hematúria/diagnóstico , Vacinas contra COVID-19/efeitos adversos , COVID-19/complicações , Recidiva Local de Neoplasia/complicações , Nefrite/complicações , Vacinação , Glomerulonefrite/complicações , Imunoglobulina ARESUMO
Glucagon-like peptide-1 receptor (GLP-1R) agonists are efficacious antidiabetic medications that work by enhancing glucose-dependent insulin secretion and improving energy balance. Currently approved GLP-1R agonists are peptide based, and it has proven difficult to obtain small-molecule activators possessing optimal pharmaceutical properties. We report the discovery and mechanism of action of LY3502970 (OWL833), a nonpeptide GLP-1R agonist. LY3502970 is a partial agonist, biased toward G protein activation over ß-arrestin recruitment at the GLP-1R. The molecule is highly potent and selective against other class B G protein-coupled receptors (GPCRs) with a pharmacokinetic profile favorable for oral administration. A high-resolution structure of LY3502970 in complex with active-state GLP-1R revealed a unique binding pocket in the upper helical bundle where the compound is bound by the extracellular domain (ECD), extracellular loop 2, and transmembrane helices 1, 2, 3, and 7. This mechanism creates a distinct receptor conformation that may explain the partial agonism and biased signaling of the compound. Further, interaction between LY3502970 and the primate-specific Trp33 of the ECD informs species selective activity for the molecule. In efficacy studies, oral administration of LY3502970 resulted in glucose lowering in humanized GLP-1R transgenic mice and insulinotropic and hypophagic effects in nonhuman primates, demonstrating an effect size in both models comparable to injectable exenatide. Together, this work determined the molecular basis for the activity of an oral agent being developed for the treatment of type 2 diabetes mellitus, offering insights into the activation of class B GPCRs by nonpeptide ligands.
Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/farmacologia , Domínios Proteicos/genética , Administração Oral , Aminopiridinas/farmacologia , Animais , Fármacos Antiobesidade/farmacologia , Benzamidas/farmacologia , Microscopia Crioeletrônica , Receptor do Peptídeo Semelhante ao Glucagon 1/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/ultraestrutura , Células HEK293 , Humanos , Incretinas/farmacologia , Macaca fascicularis , Masculino , Camundongos , Camundongos Transgênicos , Modelos Moleculares , Mutagênese Sítio-Dirigida , Ratos , Especificidade da Espécie , Suínos , Triptofano/genéticaRESUMO
In some countries, non-point source pollution derived from a city's economic activities tends to be a barrier to the improvement of water quality. Roadway runoff is known to contain toxic micro-pollutants such as polycyclic aromatic hydrocarbons (PAHs). Conversely, red soil is known to adsorb some organic matter. In this study, artificial roadway runoff water containing toxic micro-pollutants was made using roadway dust collected from a highway, and used for both batch-type tests and soil column tests with red soil in order to understand adsorption ability of the red soil on such toxic micro-pollutants, especially PAHs. In the batch-type tests, PAHs could be removed by approximately 40% when the contact time was 90 minutes. In the soil column tests, PAHs were removed by more than 80% while suspended solids were removed by more than 90%. Notably, PAHs with a high molecular weight were removed more readily in the tests than PAHs with a low molecular weight.
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Solo/química , Poluentes Químicos da Água/química , Adsorção , Automóveis , Cidades , Substâncias Perigosas/química , Hidrocarbonetos Policíclicos Aromáticos/químicaRESUMO
Insufficient evidence has been accumulated regarding associations of heated tobacco products (HTPs) use with coronavirus infection and severity of coronavirus disease 2019 (COVID-19), an ongoing pandemic. We conducted a cross-sectional study using data from an internet questionnaire administered in February 2022 to 30,130 individuals from the general Japanese population (age range, 16-81 years). Single users of HTPs and dual users of combustible cigarettes and HTPs comprised 5.2% and 7.3% of respondents, and 6.7% and 38.0% of those infected (n = 1117). Approximately 70% of infected dual users experienced severe disease. Single users of HTPs and dual users were more likely to be infected with coronavirus than never-users (adjusted odds ratio [aOR] = 1.65/4.66; 95% confidence interval [CI] 1.26-2.15/3.89-5.58). Regarding severity, former and current tobacco users (former/combustible cigarettes/HTPs: aOR = 1.88/3.17/1.90; 95%CI 1.11-3.19/1.77-5.67/1.01-3.59) were more likely to be administered oxygen than never-users, and dual users required oxygen administration the most (aOR = 4.15, 95%CI 2.70-6.36). Use of HTPs may increase risks of coronavirus infection and severe COVID-19. Our results provide an opportunity to consider the safety of tobacco products use, including HTPs, during the COVID-19 pandemic.
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COVID-19 , Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Japão/epidemiologia , Pandemias , COVID-19/epidemiologia , SARS-CoV-2 , Produtos do Tabaco/efeitos adversos , Nicotiana/efeitos adversos , Inquéritos e Questionários , Uso de TabacoRESUMO
BACKGROUND: Physical activity is one of the most important prognostic factors for patients with chronic obstructive pulmonary disease (COPD). Physical activity correlates significantly with skeletal muscle mass and strength. Pulmonary rehabilitation has been conducted to improve physical activity, but its effectiveness has been inconsistent. Nutritional status is also related to physical activity in patients with COPD. The relationships between skeletal muscle mass, strength, and nutritional status evaluated using the Mini Nutritional Assessment Short Form (MNA-SF) were investigated. How nutritional status alters the relationships between physical activity, exercise capacity, skeletal muscle mass, and strength was also investigated. METHODS: This retrospective, cross-sectional study enrolled 81 outpatients with COPD. In all patients, physical activity, exercise capacity, body composition assessment, and MNA-SF were assessed. The relationships between physical activity, exercise capacity, skeletal muscle mass, and strength were examined according to the MNA-SF. RESULTS: The MNA-SF high group had significantly higher skeletal muscle mass than the MNA-SF low group when skeletal muscle strength was the covariate. In the MNA-SF low group, physical activity positively correlated with skeletal muscle mass. In the MNA-SF high group, physical activity positively correlated with skeletal muscle strength. CONCLUSIONS: This study showed that the nutritional status of patients with COPD alters the relationship between physical activity and skeletal muscle mass or strength. Optimizing rehabilitation with nutrition interventions according to nutritional status might improve physical activity in patients with COPD.
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Desnutrição , Doença Pulmonar Obstrutiva Crônica , Humanos , Estado Nutricional , Estudos Transversais , Estudos Retrospectivos , Exercício Físico , Músculo EsqueléticoRESUMO
The carbonaceous asteroid Ryugu has been explored by the Hayabusa2 spacecraft to elucidate the actual nature of hydrous asteroids. Laboratory analyses revealed that the samples from Ryugu are comparable to unheated CI carbonaceous chondrites; however, reflectance spectra of Ryugu samples and CIs do not coincide. Here, we demonstrate that Ryugu sample spectra are reproduced by heating Orgueil CI chondrite at 300°C under reducing conditions, which caused dehydration of terrestrial weathering products and reduction of iron in phyllosilicates. Terrestrial weathering of CIs accounts for the spectral differences between Ryugu sample and CIs, which is more severe than space weathering that likely explains those between asteroid Ryugu and the collected samples. Previous assignments of CI chondrite parent bodies, i.e., chemically most primitive objects in the solar system, are based on the spectra of CI chondrites. This study indicates that actual spectra of CI parent bodies are much darker and flatter at ultraviolet to visible wavelengths than the spectra of CI chondrites.
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Sodium/glucose cotransporter 2 (SGLT2) is the predominant mediator of renal glucose reabsorption and is an emerging molecular target for the treatment of diabetes. We identified a novel potent and selective SGLT2 inhibitor, tofogliflozin (CSG452), and examined its efficacy and pharmacological properties as an antidiabetic drug. Tofogliflozin competitively inhibited SGLT2 in cells overexpressing SGLT2, and K(i) values for human, rat, and mouse SGLT2 inhibition were 2.9, 14.9, and 6.4 nM, respectively. The selectivity of tofogliflozin toward human SGLT2 versus human SGLT1, SGLT6, and sodium/myo-inositol transporter 1 was the highest among the tested SGLT2 inhibitors under clinical development. Furthermore, no interaction with tofogliflozin was observed in any of a battery of tests examining glucose-related physiological processes, such as glucose uptake, glucose oxidation, glycogen synthesis, hepatic glucose production, glucose-stimulated insulin secretion, and glucosidase reactions. A single oral gavage of tofogliflozin increased renal glucose clearance and lowered the blood glucose level in Zucker diabetic fatty rats. Tofogliflozin also improved postprandial glucose excursion in a meal tolerance test with GK rats. In db/db mice, 4-week tofogliflozin treatment reduced glycated hemoglobin and improved glucose tolerance in the oral glucose tolerance test 4 days after the final administration. No blood glucose reduction was observed in normoglycemic SD rats treated with tofogliflozin. These findings demonstrate that tofogliflozin inhibits SGLT2 in a specific manner, lowers blood glucose levels by increasing renal glucose clearance, and improves pathological conditions of type 2 diabetes with a low hypoglycemic potential.
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Compostos Benzidrílicos/farmacologia , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/farmacologia , Hemoglobinas Glicadas/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Diabetes Mellitus Tipo 2/sangue , Relação Dose-Resposta a Droga , Intolerância à Glucose/tratamento farmacológico , Teste de Tolerância a Glucose , Humanos , Hiperglicemia/sangue , Hiperglicemia/tratamento farmacológico , Rim/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Ratos , Ratos Sprague-Dawley , Ratos ZuckerRESUMO
Considering that iodine is highly volatile and has low solubility in water, it is utilized as an antiseptic in its complex form (iodophor) with a carrier material. Herein, we prepared the polysorbate 80-iodine complex and investigated its properties. In the presence of 0%, 0.01%, 0.1%, and 1% polysorbate, Pseudomonas putida NBRC 100650 growth was inhibited at 75, 75, 50, and 25 ppm iodine, respectively, indicating that high concentrations of polysorbate 80 enhanced the antibacterial activity of iodine. Absorption spectra of the mixtures of polysorbate 80 and iodine were analyzed; we observed that two peaks at 287 and 350 nm, derived from triiodide ions, shifted to the longer wavelength side in the presence of 0.1% and 1% polysorbate 80. Further, when 1% polysorbate 80 was added to the mixture of soluble starch and iodine, the peak around 580 nm arising from the amylose-iodine complex disappeared, indicating that polysorbate 80 captured iodine from the starch-iodine complex. We also found that polysorbate 80 retained iodine for approximately 4 months and prevented its volatilization; moreover, the mixture did not lose its growth inhibitory activity upon storage for approximately 4 months. Collectively, our data indicated that polysorbate 80 firmly retains low concentrations of iodine and that the polysorbate 80-iodine complex can serve as an antiseptic that can be stably stored for a long time.
Assuntos
Anti-Infecciosos Locais , Iodo , Polissorbatos , Solubilidade , Anti-Infecciosos Locais/farmacologia , Amido , IodetosRESUMO
Proton pump inhibitors (PPIs) are widely used medicines worldwide. However, a rare etiology of syndrome of inappropriate secretion of antidiuretic hormone (SIADH) related to PPI was recently reported. Therefore, the putative role of PPIs in SIADH cannot be underestimated. A 78-year-old Japanese woman was admitted to our hospital for treatment of left Bell's palsy. On admission, the patient was oriented with normal laboratory data, including a serum Na level of 135 mEq/L. Oral glucocorticoids and a proton pump inhibitor were initiated in combination with oral valaciclovir. Six days later, the patient's consciousness became impaired. Laboratory data showed a serum Na level of 103 mEq/L, a urine Na level of 64.8 mEq/L, a urine K level of 43.6 mEq/L, and a urine osmolality of 450 mOsm/kg H2O. The patient met the criteria for SIADH. The initial treatment included water restriction and 3% hypertonic saline administration. The cessation of PPI significantly improved the urine diluting capacity and concomitantly increased serum Na, which indicated that the use of PPI had been responsible for the etiology of SIADH. The present case illustrates that physicians need to be aware of the uncommon adverse effects of PPI, such as SIADH.
Assuntos
Síndrome de Secreção Inadequada de HAD/induzido quimicamente , Inibidores da Bomba de Prótons/efeitos adversos , Idoso , Feminino , Humanos , Hiponatremia/induzido quimicamenteRESUMO
BACKGROUND: Currently, in Japan, shifting tasks from physician to hospital pharmacist is being developed to reduce physician workload and improve the quality of pharmacotherapy. This study aimed to investigate the effects of pharmacist involvement in the choice of inhaler as the task on the clinical outcomes of patients with chronic obstructive pulmonary disease (COPD). METHODS: This prospective, single-center, single-arm study included 36 outpatients with newly diagnosed COPD indicating inhaler therapy. Eligible patients were immediately interviewed by pharmacist. Then, pharmacist assessed patient's inhalation flow rate, physical function to handle an inhaler, comprehension, and value, and finally recommended a personalized inhaler based on originally developed inhaler choice protocol, and pulmonologist prescribed a pharmacist-selected inhaler. The primary endpoint was the improvement in trough forced expiratory volume in 1 s (FEV1) between baseline and week 26. The secondary endpoints were safety, and improvements at week 26 in scores for the COPD Assessment Test (CAT), modified British Medical Research Council Dyspnea Scale (mMRC), and Adherence Starts with Knowledge-20 (ASK-20). RESULTS: The pneumonologists completely agreed with the pharmacist-recommended inhaler. Mean FEV1 significantly increased from baseline to week 26 (1.60, SD 0.54 L vs. 1.98, SD 0.56 L; p < 0.0001). Significant improvements in CAT, mMRC, and ASK-20 scores were also observed. The prevalence of CAT responders as a negative predictor of acute exacerbation, defined as those with a decrease in CAT score of ≥2 points from baseline, was 86%. None of the patients experienced exacerbation during the study period. CONCLUSIONS: Pharmacist involvement in the choice of inhaler for patients with newly diagnosed COPD was associated with improved lung function, health status, clinical symptoms, and adherence to inhaler therapy. Shifting task of choosing appropriate inhaler from physician to hospital pharmacist may be performed effectively and safely with an inhaler choice protocol. TRIAL REGISTRATION NUMBER: UMIN000039722 , retrospectively registered on March 10, 2020.
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The fermented soy product ImmuBalance contains many active ingredients and its beneficial effects on some allergic diseases have been reported. We hypothesized that ImmuBalance could have potential effects on airway inflammation in a murine model of asthma. Mice sensitized and challenged with ovalbumin developed airway inflammation. Bronchoalveolar lavage fluid was assessed for inflammatory cell counts and levels of cytokines. Lung tissues were examined for cell infiltration and mucus hypersecretion. Oral administration of ImmuBalance significantly inhibited ovalbumin-induced eosinophilic inflammation and decreased Th2 cytokine levels in bronchoalveolar lavage fluid (p < 0.05). In addition, lung histological analysis showed that ImmuBalance inhibited inflammatory cell infiltration and airway mucus production. Our findings suggest that supplementation with ImmuBalance may provide a novel strategy for the prevention or treatment of allergic airway inflammation.
Assuntos
Asma/terapia , Alimentos Fermentados , Glycine max/química , Inflamação/patologia , Pulmão/patologia , Animais , Peso Corporal , Líquido da Lavagem Broncoalveolar , Contagem de Células , Citocinas/metabolismo , Dieta , Modelos Animais de Doenças , Eosinófilos/metabolismo , Comportamento Alimentar , Feminino , Imunoglobulina E/sangue , Inflamação/sangue , Camundongos Endogâmicos BALB C , OvalbuminaRESUMO
Titanium (Ti) metal was treated with water or HCl solutions after 5 M NaOH solution treatment and then subjected to heat treatment at 600 degrees C. The apatite-forming abilities of the treated Ti metals were examined in simulated body fluid. The apatite-forming ability of the Ti metal subjected to NaOH, water and heat treatment was lower than that of just NaOH and heat treatments. Ti metals subjected to NaOH, HCl and heat treatment showed apatite-forming abilities, which increased with increasing HCl concentrations up to the same level as that of NaOH- and heat-treated Ti metal. The former did not show a decrease in its apatite-forming ability, even in a humid environment for a long period, whereas the latter decreased its ability. The increase in the apatite-forming ability with increasing HCl concentrations suggests a different mechanism of apatite formation from that previously proposed.
Assuntos
Apatitas/química , Temperatura Alta , Ácido Clorídrico/química , Hidróxido de Sódio/química , Titânio/química , Microscopia Eletrônica de Varredura , Análise Espectral Raman , Propriedades de Superfície , Difração de Raios XRESUMO
OBJECTIVES: Afatinib is an effective treatment in patients who have epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC), but its toxicities often require dose adjustment. Exploratory analyses of previous trials have suggested that reducing the dose of afatinib can decrease treatment-related adverse events without negatively affecting effectiveness. The aim of this study was to assess the efficacy and safety of low starting dose of afatinib with dose modification according to its toxicity in patients with EGFR mutation-positive NSCLC. MATERIALS AND METHODS: This study was a multicenter, single-arm, open-label phase II trial. Treatment-naïve patients with advanced NSCLC positive for common EGFR mutations received afatinib starting in a dose of 20 mg/day. If tolerated, the dose was increased in 10-mg increments up to 50 mg/day. The primary endpoint was progression-free survival (PFS). RESULTS: From February 2015 through March 2016, 46 patients were enrolled. The median age was 73 years (range, 43-86), and 35 patients (72%) were women.EGFR mutation subtypes included exon 19 deletion (54%) and Leu858Arg point mutation (46%). Most patients had a performance status of 0 or 1 (91%) and a histological diagnosis of adenocarcinoma (98%). As of the data cut-off date of June 2017, the median follow-up was 18.9 months. The median PFS was 15.2 months (95% CI: 13.2-not estimable). The 1-year overall survival rate was 95.6% (95% CI: 89.7%-100%). The objective response rate was 81.8% (95% CI, 81.3%-98.6%). Adverse events of grade 3 or higher occurred in 14 patients (30.4%) and included rash/acne in 4 patients (8.7%), paronychia in 4 patients (8.7%), diarrhea in 2 patients (4.3%). There was no treatment-related death. CONCLUSIONS: Low starting dose of afatinib therapy showed promising clinical efficacy and good tolerability. Further investigations are warranted.
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Afatinib/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Adulto , Afatinib/administração & dosagem , Afatinib/efeitos adversos , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Receptores ErbB/genética , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Resultado do TratamentoRESUMO
Adding fatty acids to an oil-in-water (O/W) emulsion changes the stability of the emulsion. In this study, we prepared a series of O/W emulsions consisting of oil (triolein/fatty acid mixture), water and a range of surfactants (sucrose fatty acid esters) with varying hydrophilic-lipophilic balance (HLB) in order to determine the effects of alkyl chain length and the degree of unsaturation of the fatty acid molecules on the stability of the emulsions. As a result, sucrose fatty acid esters with HLB = 5-7 were suitable for obtaining O/W emulsions. In addition, the creaming phenomenon was inhibited for 30 days or more when fatty acids having a linear saturated alkyl chain with 14 or more carbon atoms were added. These findings are useful for designing stable O/W emulsions for food and cosmetic products.
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Estabilidade de Medicamentos , Emulsões , Ésteres/química , Ácidos Graxos/química , Óleos , Sacarose/química , Tensoativos/química , Água , Cosméticos , Alimentos , Interações Hidrofóbicas e HidrofílicasRESUMO
We present the case of a 53-year-old man who underwent a total arch replacement for descending thoracic aortic aneurysm of distal anastomosis site after bypass grafting for coarctation of the aorta at 26 years of age.
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Aneurisma da Aorta Torácica/cirurgia , Coartação Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/etiologia , Implante de Prótese Vascular/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
Ruptured aortic root aneurysm is very rare in children less than 10 years of age. Isolated dilatation of the ascending aorta and/or aortic root in a child is mostly associated with Marfan's syndrome, and the standard surgical treatment is aortic root replacement with a composite valve graft or homograft. We report here a successful emergent T. David-V operation using two grafts of different sizes for a ruptured aortic root aneurysm in a 9-year-old child with Marfan's syndrome.
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Ruptura Aórtica/cirurgia , Aorta/patologia , Ruptura Aórtica/complicações , Ruptura Aórtica/diagnóstico por imagem , Criança , Dilatação Patológica/cirurgia , Ecocardiografia/métodos , Humanos , Masculino , Síndrome de Marfan/complicações , Síndrome de Marfan/diagnóstico por imagem , Síndrome de Marfan/cirurgia , Procedimentos Cirúrgicos Vasculares/métodosRESUMO
Bacteria play a crucial role in skin health. For example, Staphylococcus aureus and Propionibacterium acnes cause skin roughness and acne, whereas Staphylococcus epidermidis enhances innate barrier immunity. Therefore, controlling the bacterial flora is important in dermatology and cosmetic chemistry. In this study, the bactericidal activities of different metal salts of lauric acid were evaluated. The bactericidal behavior of the salts changed according to the type of metal ion. Specifically, the Mg-, Ca-, and Mn-containing salts effectively sterilized only S. aureus and P. acnes. Their Co, Ni, and Cu salts sterilized all bacteria, including S. epidermidis, whereas the Zn salt proved ineffective. The Cu salt displayed the strongest bactericidal activity. Spin-trapping, detected using electron spin resonance, showed that this salt catalyzed the generation of hydroxyl radicals, which can destroy bacterial cell membranes. These findings demonstrate that metal-ion selection is an important factor in the design of bactericidal agents for healthcare products.
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Streptomyces albulus IFO14147 produces epsilon-poly-L-lysine (epsilon-PL), an amino acid homopolymer antibiotic that is used as a food preservative in many countries, including Japan, South Korea, and the United States. To construct an overproducer of the industrially important epsilon-PL and to develop a deeper understanding of its biosynthetic mechanism, we developed systems for DNA delivery into the S. albulus strain based on both polyethylene glycol-mediated protoplast transformation and intergeneric conjugation from Escherichia coli. The successes of these transformations in particular were accomplished by employing the new cryptic-plasmid-based shuttle vectors constructed in this study. The genetic systems developed here should facilitate a molecular genetic approach to S. albulus.
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Sistemas de Liberação de Medicamentos/métodos , Marcação de Genes/métodos , Polietilenoglicóis/química , Polilisina/biossíntese , Streptomyces/genética , Streptomyces/metabolismo , Transformação Bacteriana , Escherichia coli/genética , Escherichia coli/metabolismo , Especificidade da Espécie , Streptomyces/classificaçãoRESUMO
Coating organic polymers with hydroxyapatite is an attractive method for the development of materials for medical applications, as it allows hydroxyapatite to show its unique biological properties such as its ability for bone bonding and protein adsorption. The biomimetic process focuses attention on fabricating such hydroxyapatite-polymer hybrids, where bone-like apatite is deposited on an organic polymer surface in solutions mimicking physiological conditions. In this process, a bone-like apatite layer can be coated onto organic substrates either by using a simulated body fluid (SBF), which has ion concentrations nearly equal to those of human extracellular fluid, or by using fluids that are supersaturated with respect to apatite at ambient conditions. We previously reported that apatite was deposited on polyamide films containing carboxyl groups in a solution mimicking body fluid, when they were incorporated with calcium salts. In the present study, to find an alternative functional group effective in apatite formation, we examined the apatite-forming ability of polyamide films containing sulfonic groups in the same solution. It was found that the polyamide film containing sulfonic groups could deposit apatite on its surface in the solution when the film was incorporated with calcium salts. These results show that the sulfonic group also acts as a functional group, and is as effective for apatite deposition in the body environment as the carboxyl group.
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Biomimética/métodos , Líquidos Corporais/química , Substitutos Ósseos/química , Materiais Revestidos Biocompatíveis/química , Cristalização/métodos , Durapatita/química , Nylons/química , Materiais Biocompatíveis/química , Teste de Materiais , Membranas Artificiais , Conformação Molecular , Sulfonas/química , Propriedades de SuperfícieRESUMO
Guanine derivatives connected to pyrene with methylene spacers exhibited exciplex emission in highly polar solvents such as N,N-dimethylformamide, acetonitrile, and water. The result will open up a novel approach to synthesis of fluorescent nucleic bases.