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1.
Acc Chem Res ; 56(12): 1359-1372, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37256726

RESUMO

ConspectusChirality is ubiquitous in the universe and in living creatures over detectable length scales from the subatomic to the galactic, as exemplified in the two extremes by subatomic particles (neutrinos) and spiral galaxies. Between them are living creatures that display multiple levels of chirality emerging from hierarchically assembled asymmetric building blocks. Not too far from the bottom of this pyramid are the foundational building blocks with chiral atomic centers on sp3 carbon atoms exemplified by l-amino acids and d-sugars that are self-assembled into higher-order structures with increasing dimensions forming highly complex, amazingly functional, and energy-efficient living systems. The organization and materials employed in their construction inspired scientists to replicate complex living systems via the self-assembly of chiral components. Multiple studies pointed to unexpected and unique electromagnetic properties of chiral structures with nanoscale and microscale dimensions, including giant circular dichroism and collective circularly polarized scattering that their constituent units did not possess.To address the wide variety of chiral geometries observed in continuous materials, singular particles, and their complex systems, multiple analytic techniques are needed. Simultaneously, their spectroscopic properties create a pathway to multiple applications. For example, mirror-asymmetric vibrations at chiral centers formed by sp3 carbon atoms lead to optical activity for the infrared (IR) wavelength regions. At the same time, understanding the optical activity in, for example, the IR region enables biomedical applications because multiple modalities of biomedical imaging and vibrational optical activity (VOA) of biomolecules are known for IR range. In turn, VOA can be realized in both absorption and emission modalities due to large magnetic transition moments, as vibrational circular dichroism (VCD) or Raman optical activity (ROA) spectroscopy. In addition to the VOA, in the range of longer wavelengths, lattice vibrational mode or phononic behavior occurs in chiral crystals and nanoassemblies, which can be readily detected by terahertz circular dichroism (TCD) spectroscopy. Meanwhile, chiral self-assembly can induce circularly polarized light emission (CPLE) regardless of the existence of chirality in coassembled fluorophores. The CPLE from self-assembled chiral materials is particularly interesting because the CPLE can originate from both circularly polarized luminescence and circularly polarized scattering (CPS). Furthermore, because self-assembled nanostructures often exhibit stronger optical activity than their building blocks owing to dimension and resonance effects, the optical activity of single assembled nanostructures can be investigated by using microscopic technology combined with chiral optics. Here, we describe the state of the art for spectroscopic methods for the comprehensive analysis of chiral nanomaterials at various photon wavelengths, addressed with special attention given to new tools emerging both for materials with self-organized hierarchical chirality and single-particle spectroscopy.

2.
Int J Mol Sci ; 22(2)2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467096

RESUMO

B cell activating factor (BAFF) is a cytokine that plays a role in the survival, proliferation and differentiation of B cells. We proposed to observe the effects of BAFF inhibition on the humoral immune responses of an allosensitized mouse model using HLA.A2 transgenic mice. Wild-type C57BL/6 mice were sensitized with skin allografts from C57BL/6-Tg (HLA-A2.1)1Enge/J mice and were treated with anti-BAFF monoclonal antibody (mAb) (named Sandy-2) or control IgG1 antibody. HLA.A2-specific IgG was reduced in BAFF-inhibited mice compared to the control group (Δ-13.62 vs. Δ27.07, p < 0.05). BAFF inhibition also resulted in increased pre-pro and immature B cell proportions and decreased mature B cells in the bone marrow (p < 0.05 vs. control). In the spleen, an increase in transitional B cells was observed with a significant decrease in marginal and follicular B cells (p < 0.05 vs. control). There was no significant difference in the proportions of long-lived plasma and memory B cells. Microarray analysis showed that 19 gene probes were significantly up- (>2-fold, p < 0.05) or down-regulated (≤2-fold, p < 0.05) in the BAFF-inhibited group. BAFF inhibition successfully reduced alloimmune responses through the reduction in alloantibody production and suppression of B cell differentiation and maturation. Our data suggest that BAFF suppression may serve as a useful target in desensitization therapy.


Assuntos
Fator Ativador de Células B/antagonistas & inibidores , Antígeno HLA-A2/imunologia , Imunização , Aloenxertos/imunologia , Animais , Anticorpos/imunologia , Linfócitos B/imunologia , Células da Medula Óssea/imunologia , Imunoglobulina G/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Pele/efeitos adversos , Baço/citologia , Baço/imunologia
3.
Int J Mol Sci ; 21(10)2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32455959

RESUMO

Cytomegalovirus (CMV) infection has a significant impact in patients after allogeneic hematopoietic stem cell transplantation (HSCT). We investigated natural killer (NK) cell reconstitution and cytotoxic/cytokine production in controlling CMV infection, especially severe CMV disease in HSCT patients. Fifty-eight patients with acute myeloid leukemia (AML) who received allo-HSCT were included. We monitored NK reconstitution and NK function at baseline, 30, 60, 90, 120, 150, and 180 days after HSCT, and compared the results in recipients stratified on post-HSCT CMV reactivation (n = 23), non-reactivation (n = 24) versus CMV disease (n = 11) groups. The CMV disease group had a significantly delayed recovery of CD56dim NK cells and expansion of FcRγ-CD3ζ+NK cells started post-HSCT 150 days. Sequential results of NK cytotoxicity, NK cell-mediated antibody-dependent cellular cytotoxicity (NK-ADCC), and NK-Interferon-gamma (NK-IFNγ) production for 180 days demonstrated delayed recovery and decreased levels in the CMV disease group compared with the other groups. The results within 1 month after CMV viremia also showed a significant decrease in NK function in the CMV disease group compared to the CMV reactivation group. It suggests that NK cells' maturation and cytotoxic/IFNγ production contributes to CMV protection, thereby revealing the NK phenotype and functional NK monitoring as a biomarker for CMV risk prediction, especially CMV disease.


Assuntos
Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Transplante de Células-Tronco Hematopoéticas , Células Matadoras Naturais/imunologia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/virologia , Adolescente , Adulto , Idoso , Linhagem Celular Tumoral , Infecções por Citomegalovirus/complicações , Feminino , Humanos , Imunofenotipagem , Interferon gama/metabolismo , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Receptores de Células Matadoras Naturais/metabolismo , Fatores de Risco , Transplante Homólogo
4.
Int J Mol Sci ; 20(21)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671661

RESUMO

Although natural killer (NK) cell function is a hallmark of hemophagocytic lymphohistiocytosis (HLH), there is no standard method or data on its diagnostic value in adults. Thus, we performed a single-center retrospective study of 119 adult patients with suspected HLH. NK cell function was determined using both flowcytometry-based NK-cytotoxicity test (NK-cytotoxicity) and NK cell activity test for interferon-gamma (NKA-IFNγ). NK cell phenotype and serum cytokine levels were also tested. Fifty (42.0%) HLH patients showed significantly reduced NK cell function compared to 69 non-HLH patients by both NK-cytotoxicity and NKA-IFNγ (p < 0.001 and p = 0.020, respectively). Agreement between NK-cytotoxicity and NKA-IFNγ was 88.0% in HLH patients and 58.0% in non-HLH patients. NK-cytotoxicity and NKA-IFNγ assays predicted HLH with sensitivities of 96.0% and 92.0%, respectively. The combination of NKA-IFNγ and ferritin (>10,000 µg/L) was helpful for ruling out HLH, with a specificity of 94.2%. Decreased NK-cytotoxicity was associated with increased soluble IL-2 receptor levels and decreased CD56dim NK cells. Decreased NKA-IFNγ was associated with decreased serum cytokine levels. We suggest that both NK-cytotoxicity and NKA-IFNγ could be used for diagnosis of HLH. Further studies are needed to validate the diagnostic and prognostic value of NK cell function tests.


Assuntos
Interferon gama/metabolismo , Células Matadoras Naturais/metabolismo , Linfo-Histiocitose Hemofagocítica/diagnóstico , Adulto , Idoso , Testes Imunológicos de Citotoxicidade , Diagnóstico Precoce , Feminino , Ferritinas/metabolismo , Citometria de Fluxo , Humanos , Interferon gama/sangue , Células Matadoras Naturais/imunologia , Linfo-Histiocitose Hemofagocítica/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Scand J Clin Lab Invest ; 78(7-8): 606-612, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30375892

RESUMO

In vitro allergen-specific immunoglobulin E (sIgE) measurement has been used as an important diagnostic tool for allergic diseases. Currently, quantitative sIgE levels are detected mainly by using ImmunoCAP and Immulite 2000 assay system. These two systems have the same calibration scale at 0-100 kUA/L, but they differ in used allergens, detection methods and automation systems. We compared 1600 paired sIgE results for 204 allergic patients, including 100 paired sIgE assay results for each of 16 allergens (Alternaria alternata, birch-alder mix, cat dander, D. farinae, D. pteronyssinus, dog dander, buckwheat, crab, egg white, mackerel, milk, peach, peanut, shrimp, soybean and wheat flour). Inter-method comparison was performed for qualitative data with a cutoff of 0.35 kUA/L and a detection limit of 0.1 kUA/L, semi-quantitative class results and quantitative data. In qualitative comparisons, the overall concordance rate ranged from 81.0% to 99.0% (k: 0.599-0.949) with the cutoff value of 0.35 kUA/L. It also ranged from 80.0% to 99.0% (k: 0.521-0.951) with the detection limit of 0.1 kUA/L. The class results from these two assays showed good agreements for all allergens. For quantitative sIgE results, these two assays showed moderate positive correlations for Dog dander (r = 0.683) and Mackerel (r = 0.573) but high to very high correlations for the other 14 allergens (r = 0.734-0.972). Immulite 2000 and ImmunoCAP assays demonstrated good concordance and correlation for 16 common allergens, but international standards against each specific allergen for calibration and harmonization of sIgE tests are still needed.


Assuntos
Alérgenos/imunologia , Hipersensibilidade Alimentar/diagnóstico , Imunoensaio/métodos , Imunoglobulina E/sangue , Hipersensibilidade Respiratória/diagnóstico , Adulto , Calibragem , Feminino , Hipersensibilidade Alimentar/imunologia , Humanos , Masculino , Hipersensibilidade Respiratória/imunologia , Sensibilidade e Especificidade
6.
BMC Complement Altern Med ; 18(1): 40, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29385996

RESUMO

BACKGROUND: Cold hypersensitivity in the hands and feet (CHHF) is a common symptom in Korea and patients with CHHF complain of coldness in the hands and feet in an environment that is not considered cold by unaffected people. In traditional East Asian medicine, CHHF is believed to be accompanied by various diseases and symptoms, and is considered a symptom that needs active treatment. CHHF is used for pattern identification in the cold pattern, yang deficiency, and constitution. This study aimed to examine the differences in frequencies of chronic diseases with respect to the presence of CHHF. METHODS: Disease history, CHHF, body measurements, and blood test survey data from 6149 patients collected by 25 medical institutes in Korea were obtained from the Korean Medicine Data Center. The participants were divided into CHHF (n = 1909) and non-CHHF groups (n = 3017) according to the CHHF survey. The differences in frequencies of 18 diseases were analysed using chi-square tests, and the odds ratios (ORs) for each disease according to CHHF status were examined via logistic regression with adjustment for age, sex, and body mass index (BMI). RESULTS: Based on chi-square test results, the CHHF group showed a higher frequency of the following diseases: anaemia, hypotension, chronic gastritis, reflux oesophagitis, chronic rhinitis, dysmenorrhoea, and gastroduodenal ulcer. Diseases found in lower frequencies were as follows: hypertension, diabetes mellitus, impaired fasting glucose, dyslipidaemia, stroke, fatty liver, and angina pectoris. In addition, from the logistic regression with adjustment for age, sex, and BMI, the CHHF group showed a lower OR in diabetes mellitus and dyslipidaemia than the non-CHHF group, but a higher OR in degenerative arthritis, chronic gastritis, gastroduodenal ulcer, reflux oesophagitis, and chronic rhinitis. CONCLUSIONS: This study showed that CHHF is associated with chronic disease. Further large-scale prospective studies are needed to validate these associations.


Assuntos
Doença Crônica/epidemiologia , Síndromes Periódicas Associadas à Criopirina/complicações , Síndromes Periódicas Associadas à Criopirina/epidemiologia , Pé/fisiopatologia , Mãos/fisiopatologia , Adulto , Estudos Transversais , Feminino , Pé/irrigação sanguínea , Mãos/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
7.
J Bone Miner Metab ; 35(6): 642-648, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27873074

RESUMO

Results regarding the association between adipokine levels and bone mineral density (BMD) have been inconsistent; the effects of sex, menopause, and central obesity remain unknown. We evaluated the association between serum leptin, adiponectin, and high-molecular-weight (HMW) adiponectin levels and BMD according to menopause and central obesity status in Korean women. This cross-sectional study comprised 255 women undergoing examinations at the CHA Bundang Medical Center. Participants were divided according to menopause, and central obesity status. We measured serum adipokine levels and BMD using an enzyme-linked immunosorbent assay and dual-energy X-ray absorptiometry, respectively. After adjusting for age, body mass index, alkaline phosphatase levels and the Homeostasis Model Assessment index, leptin levels were negatively associated with non-vertebral BMD (total hip, ß = -0.576, P = 0.006; femoral neck, ß = -0.608, P = 0.007) in postmenopausal women without central obesity. Among women without central obesity, HMW adiponectin levels were positively associated with total hip BMD (ß = 0.240, P = 0.010) in premenopausal women but negatively associated with BMD (lumbar, ß = -0.436, P = 0.012; femoral neck, ß = -0.468, P = 0.007) in postmenopausal women. Thus, the association between adipokine levels and BMD varies according to the menopause and central obesity status.


Assuntos
Adipocinas/sangue , Densidade Óssea , Menopausa/sangue , Obesidade/sangue , Obesidade/fisiopatologia , Absorciometria de Fóton , Adiponectina/sangue , Adulto , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Leptina/sangue , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Pré-Menopausa , Análise de Regressão , República da Coreia
8.
Public Health Nutr ; 20(10): 1836-1843, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27373847

RESUMO

OBJECTIVE: To examine the hypothesis that the association between vitamin D deficiency and depressive symptoms is dependent upon total cholesterol level in a representative national sample of the South Korean population. DESIGN: This was a population-based cross-sectional study. SETTING: The Fifth Korean National Health and Nutrition Examination Survey (KNHANES V, 2010-2012). SUBJECTS: We included 7198 adults aged 20-88 years. RESULTS: The incidence of depressive symptoms in individuals with vitamin D deficiency (serum 25-hydroxyvitamin D<20 ng/ml) was 1·54-fold (95 % CI 1·20, 1·98) greater than in individuals without vitamin D deficiency (serum 25-hydroxyvitamin D ≥20 ng/ml). The relationship was stronger in individuals with normal-to-borderline serum total cholesterol (serum total cholesterol<240 mg/dl; OR=1·60; 95 % CI 1·23, 2·08) and non-significant in individuals with high serum total cholesterol (OR=0·97; 95 % CI 0·52, 1·81) after adjustment for confounding variables (age, sex, BMI, alcohol consumption, smoking status, regular exercise, income level, education level, marital status, changes in body weight, perceived body shape, season of examination date and cholesterol profiles). CONCLUSIONS: The association between vitamin D deficiency and depressive symptoms was weakened by high serum total cholesterol status. These findings suggest that both vitamin D and total cholesterol are important targets for the prevention and treatment of depression.


Assuntos
Colesterol/sangue , Depressão/epidemiologia , Inquéritos Nutricionais/estatística & dados numéricos , Vitamina D/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Depressão/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Fatores de Risco , Vitamina D/sangue , Adulto Jovem
9.
BMC Cancer ; 16: 385, 2016 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-27377907

RESUMO

BACKGROUND: Bone metastasis is relatively uncommon in gastric cancer patients, but its incidence has been rising. Early detection of bone metastasis is important in preventing complications related to bone metastasis such as pain, fracture and the compromise of chemotherapy. In this pilot study, we investigated the feasibility of bone turnover markers as surrogate markers of bone metastasis in gastric cancer patients. METHODS: Fifty-eight patients with gastric cancer were included in this study. Serum levels of bone alkaline phosphatase (ALP), parathyroid hormone (PTH), 25(OH) D, osteocalcin (OC) and C terminal telopeptide were measured and compared between patients with bone metastasis and those without. Student's t-test and Mann-Whitney U test were used in comparing two groups, and Spearman's rank order correlation coefficient was calculated to quantify the strength of the associations. RESULTS: Fifty eight age- and sex-matched patients were evaluated for bone turnover markers, among whom 29 patients had bone metastasis and 29 patients with no bone metastasis. The median age was 62 and there were 20 (68.9 %) males and 9 (31.1 %) females in each group. Bone ALP was significantly higher in the patient group (57.32 ± 46.83 vs. 34.57 ± 21.57, P = 0.037) than control group. Bone ALP was positively associated with ALP, osteocalcin, CA19-9, CA 72-4 and negatively associated with 25(OH) D. According to ROC-curve analysis, at the threshold value of 29.60 µg/L, the sensitivity of bone ALP was 76.7 % and the specificity was 59.4 %. CONCLUSION: Bone ALP may be a surrogate marker of bone metastasis in gastric cancer patients. More prospective studies are warranted to determine the optimal bone turnover markers in the evaluation of bone metastasis.


Assuntos
Fosfatase Alcalina/sangue , Biomarcadores Tumorais/sangue , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/secundário , Neoplasias Gástricas/metabolismo , Neoplasias Ósseas/metabolismo , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Neoplasias Gástricas/patologia
10.
J Korean Med Sci ; 31(8): 1337-44, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27478348

RESUMO

Positive fluid balance is a risk factor for mortality in critically ill patients, especially those requiring continuous renal replacement therapy (CRRT). However, the association between daily fluid balance and various organ impairments remains unclear. This study investigated the impacts of daily fluid balance prior to CRRT on organ dysfunction, as well as mortality in critically ill patients. We identified daily fluid balance between intensive care unit (ICU) admission and CRRT initiation. According to daily fluid balance, the time to CRRT initiation and the rate of organ failure based on the sequential organ failure assessment (SOFA) score were assessed. We recruited 100 patients who experienced CRRT for acute kidney injury. CRRT was initiated within 2 [0, 4] days. The time to CRRT initiation was shortened in proportion to daily fluid balance, even after the adjustment for the renal SOFA score at ICU admission (HR 1.14, P = 0.007). Based on the SOFA score, positive daily fluid balance was associated with respiratory, cardiovascular, nervous, and coagulation failure, independent of each initial SOFA score at ICU admission (HR 1.36, 1.26, 1.24 and 2.26, all P < 0.05). Ultimately, we found that positive fluid balance was related with an increase in the rate of 28-day mortality (HR 1.14, P = 0.012). Positive daily fluid balance may accelerate the requirement for CRRT, moreover, it can be associated with an increased risk of multiple organ failure in critically ill patients.


Assuntos
Injúria Renal Aguda/diagnóstico , Estado Terminal/mortalidade , Terapia de Substituição Renal , Equilíbrio Hidroeletrolítico/fisiologia , Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Idoso , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
11.
Korean J Fam Med ; 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38263900

RESUMO

Background: Osteoporosis is one of the inevitable diseases affecting an aging society, substantially impacting the quality of life of its population. Protein intake has been shown to be beneficial in reducing the incidence of osteoporosis, and the effects of both animal and vegetable proteins have been studied. However, the relationship between processed meat consumption and osteoporosis has not been studied in Korea. Therefore, we aimed to analyze the correlation between processed meat consumption and incident osteoporosis in adults. Methods: Our analysis included 1,260 adults aged 50 years and older from the Korean Genome and Epidemiology Study (KoGES), recruited between 2005 and 2020. Participants were categorized into two groups according to their processed meat intake, assessed using a semi-quantitative 103-food item food frequency questionnaire. Diagnosis of osteoporosis was based on questionnaire answers. Multiple Cox hazard regression analyses were conducted to examine the association between processed meat intake and incident osteoporosis. Results: During an average follow-up period of 8.8 years, 230 participants developed osteoporosis. According to the Cox proportional regression models, the hazard ratio (95% confidence interval) of incident osteoporosis in the high intake group was 0.62 (0.41-0.94), compared to the low intake group after adjusting for confounding variables. Conclusion: These findings reveal that processed meat protein intake is inversely related to the incidence of osteoporosis in adults aged 50 years and older. This in turn suggests that processed meat intake can be proposed as an additional strategy to prevent osteoporosis.

12.
Nat Commun ; 15(1): 6996, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143052

RESUMO

Three-dimensional optical nanostructures have garnered significant interest in photonics due to their extraordinary capabilities to manipulate the amplitude, phase, and polarization states of light. However, achieving complex three-dimensional optical nanostructures with bottom-up fabrication has remained challenging, despite its nanoscale precision and cost-effectiveness, mainly due to inherent limitations in structural controllability. Here, we report the optical characteristics of intricate two- and three-dimensional nanoarchitectures made of colloidal quantum dots fabricated with multi-dimensional transfer printing. Our customizable fabrication platform, directed by tailored interface polarity, enables flexible geometric control over a variety of one-, two-, and three-dimensional quantum dot architectures, achieving tunable and advanced optical features. For example, we demonstrate a two-dimensional quantum dot nanomesh with tuned subwavelength square perforations designed by finite-difference time-domain calculations, achieving an 8-fold enhanced photoluminescence due to the maximized optical resonance. Furthermore, a three-dimensional quantum dot chiral structure is also created via asymmetric stacking of one-dimensional quantum dot layers, realizing a pronounced circular dichroism intensity exceeding 20°.

13.
ACS Appl Mater Interfaces ; 15(40): 46829-46839, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37756659

RESUMO

Noble metals (Pt) and metal oxides (IrC and RuO2) are heavily utilized as benchmark electrocatalysts for alkaline water splitting; however, these materials possess several drawbacks including high cost, poor selectivity and stability, and high environmental impact. To address these issues, we synthesized a novel metal-free conducting polypyrrole-polythiophene (Ppy-Ptp) copolymer and a separate Ppy electrode material for water-splitting applications. The Ppy-Ptp and Ppy electrocatalysts exhibited remarkable activity in the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively. The optimal Ppy-Ptp (1:3) formulation, when deposited on a conductive nickel foam (NF) substrate, exhibited an exceptional OER performance with a low overpotential of approximately 250 mV at 20 mAcm-2, thereby outperforming the benchmark IrC/NF electrocatalyst (290 mV, 20 mAcm-2). Additionally, a similarly prepared Ppy/NF electrocatalyst exhibited an extraordinary HER performance with an overpotential of approximately 72 mV at 10 mA cm-2. Furthermore, an alkaline anion-exchange membrane (AEM) electrolyzer incorporating Ppy-Ptp (1:3) and Ppy as the anode and cathode materials, respectively, displayed operating potentials of 1.55, 1.70, and 1.78 V at 10, 50, and 100 mA cm-2, which are lower than those observed in previously reported electrolyzers. This electrolyzer also exhibited considerable operational endurance over 50 h at 50 mA cm-2, over which a negligible decay of 0.02 V was observed. The novel polymer-based metal-free catalysts presented herein therefore exhibit considerable potential as alternative electrocatalytic materials for sustainable industrial-scale H2 synthesis.

14.
Appl Environ Microbiol ; 78(23): 8454-62, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23042178

RESUMO

Pseudomonas fluorescens, a widespread Gram-negative bacterium, is an ideal protein manufacturing factory (PMF) because of its safety, robust growth, and high protein production. P. fluorescens possesses a type I secretion system (T1SS), which mediates secretion of a thermostable lipase (TliA) and a protease (PrtA) through its ATP-binding cassette (ABC) transporter. Recombinant proteins in P. fluorescens are attached to the C-terminal signal region of TliA for transport as fusion proteins to the extracellular medium. However, intrinsic TliA from the P. fluorescens genome interferes with detection of the recombinant protein and the secreted recombinant protein is hydrolyzed, due to intrinsic PrtA, resulting in decreased efficiency of the PMF. In this research, the lipase and protease genes of P. fluorescens SIK W1 were deleted using the targeted gene knockout method. Deletion mutant P. fluorescens ΔtliA ΔprtA secreted fusion proteins without TliA or protein degradation. Using wild-type P. fluorescens as an expression host, degradation of the recombinant protein varied depending on the type of culture media and aeration; however, degradation did not occur with the P. fluorescens ΔtliA ΔprtA double mutant irrespective of growth conditions. By homologous expression of tliA and the ABC transporter in a plasmid, TliA secreted from P. fluorescens ΔprtA and P. fluorescens ΔtliA ΔprtA cells was found to be intact, whereas that secreted from the wild-type P. fluorescens and P. fluorescens ΔtliA cells was found to be hydrolyzed. Our results demonstrate that the P. fluorescens ΔtliA ΔprtA deletion mutant is a promising T1SS-mediated PMF that enhances production and detection of recombinant proteins in extracellular media.


Assuntos
Lipase/genética , Peptídeo Hidrolases/genética , Pseudomonas fluorescens/enzimologia , Pseudomonas fluorescens/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Meios de Cultura/química , Técnicas de Inativação de Genes , Lipase/metabolismo , Engenharia Metabólica , Peptídeo Hidrolases/metabolismo , Transporte Proteico , Pseudomonas fluorescens/metabolismo
15.
Travel Med Infect Dis ; 48: 102333, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35452835

RESUMO

OBJECTIVES: To elucidate the relationship between CYP2D6 polymorphisms and Plasmodium vivax recurrence in patients receiving primaquine-based treatment through systematic review and meta-analysis. METHODS: We searched the PubMed, EMBASE, Cochrane Library, and Web of Science databases for eligible studies published up to August of 2021. We included studies investigating the associations between CYP2D6 polymorphisms and P. vivax recurrence. We evaluated the pooled odds ratio (OR) and 95% confidence interval (CI). RESULTS: Data from nine studies, including 970 patients, were analyzed. We found that CYP2D6 poor metabolizers (PMs), intermediate metabolizers (IMs), or normal metabolizers slow (NM-Ss) were associated with a 1.8-fold (95% CI, 1.34-2.45; P = 0.0001) higher recurrence of P. vivax than normal metabolizers fast (NM-Fs), extensive metabolizers (EMs), or ultrarapid metabolizer (UMs). Subgroup analysis showed that studies on both Brazilian and Southeast or East Asian individuals had similar results to the main results. Sensitivity analysis by sequentially excluding individual studies also showed robust results (OR range: 1.63-2.01). CONCLUSIONS: This meta-analysis confirmed that CYP2D6 PMs, IMs, or NM-Ss increased the risk of P. vivax recurrence compared to NM-Fs, EMs, or UMs. The results of this study could be used to predict P. vivax recurrence and suggest CYP2D6 genotype-based primaquine dosing.


Assuntos
Antimaláricos , Malária Vivax , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/farmacologia , Citocromo P-450 CYP2D6/uso terapêutico , Genótipo , Humanos , Malária Vivax/tratamento farmacológico , Plasmodium vivax/genética , Primaquina/uso terapêutico , Recidiva
16.
Adv Mater ; 34(35): e2200408, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35799313

RESUMO

Biological systems consist of hierarchical protein structures, each of which has unique 3D geometries optimized for specific functions. In the past decades, the growth of inorganic materials on specific proteins has attracted considerable attention. However, the use of specific proteins as templates has only been demonstrated in relatively simple organisms, such as viruses, limiting the range of structures that can be used as scaffolds. This study proposes a method for synthesizing metallic structures that resemble the 3D assemblies of specific proteins in mammalian cells and animal tissues. Using 1.4 nm nanogold-conjugated antibodies, specific proteins within cells and ex vivo tissues are labeled, and then the nanogold acts as nucleation sites for growth of metal particles. As proof of concept, various metal particles are grown using microtubules in cells as templates. The metal-containing cells are applied as catalysts and show catalytic stability in liquid-phase reactions due to the rigid support provided by the microtubules. Finally, this method is used to produce metal structures that replicate the specific protein assemblies of neurons in the mouse brain or the extracellular matrices in the mouse kidney and heart. This new biotemplating approach can facilitate the conversion of specific protein structures into metallic forms in ex vivo multicellular organisms.


Assuntos
Mamíferos , Metais , Animais , Catálise , Metais/química , Camundongos
17.
Nano Converg ; 9(1): 32, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35851425

RESUMO

Research on chiral nanomaterials (NMs) has grown radically with a rapid increase in the number of publications over the past decade. It has attracted a large number of scientists in various fields predominantly because of the emergence of unprecedented electric, optical, and magnetic properties when chirality arises in NMs. For applications, it is particularly informative and fascinating to investigate how chiral NMs interact with electromagnetic waves and magnetic fields, depending on their intrinsic composition properties, atomic distortions, and assembled structures. This review provides an overview of recent advances in chiral NMs, such as semiconducting, metallic, and magnetic nanostructures.

18.
ACS Nano ; 15(9): 15229-15237, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34519483

RESUMO

Chiral nanomaterials provide a rich platform for versatile applications. Tuning the wavelength of polarization rotation maxima in the broad range including short-wave infrared (SWIR) is a promising candidate for infrared neural stimulation, imaging, and nanothermometry. However, the majority of previously developed chiral nanomaterials reveal the optical activity in a relatively shorter wavelength range (ultraviolet-visible, UV-vis), not in SWIR. Here, we demonstrate a versatile method to synthesize chiral copper sulfides using cysteine, as the stabilizer, and transferring the chirality from molecular- to the microscale through self-assembly. The assembled structures show broad chiroptical activity in the UV-vis-NIR-SWIR region (200-2500 nm). Importantly, we can tune the chiroptical activity by simply changing the reaction conditions. This approach can be extended to materials platforms for developing next-generation optical devices, metamaterials, telecommunications, and asymmetric catalysts.

19.
Medicine (Baltimore) ; 100(25): e26372, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34160410

RESUMO

RATIONALE: Idiopathic ventricular tachycardia (VT) occurs in individuals without structural abnormalities in the heart, accounts for approximately 10% of total VTs. Furthermore, approximately 70% of idiopathic VTs originate from Right ventricular outflow tract (RVOT). However, among perioperative arrhythmias, incidence of VT after surgery is extremely rare and most arrhythmias are atrial origin. PATIENT CONCERNS: A 69-year-old man with permanent pacemaker underwent colon surgery. DIAGNOSES: Patient suffered from low blood pressure and dizziness, sweating at post anesthetic care unit (PACU) and heart rate (HR) increased suddenly to 200 beats/min with monomorphic VT after bolus ephedrine administration and continuous dopamine infusion. INTERVENTIONS: Pacemaker interrogation followed by DC cardioversion was done. OUTCOMES: Patient's vital signs became normal and symptoms are subsided. LESSONS: RVOT VT can be caused by triggering activities, such as ephedrine, dopamine, and inadequate fluid management. These triggering activities are initiated by acceleration of HR from ventricles with infusion of catecholamine which lead monomorphic VT originating from RVOT.RVOT origin PVCs can be precipitated into monomorphic VT by administrating catecholamines such as ephedrine and dopamine even in patient with pacemaker. The mechanism of these VTs includes catecholamine induced acceleration of HR. Since RVOT PVCs can be recognize by 12 EKGs, we should be pay more attentions to the pre-operation EKG and be cautious using catecholamines.


Assuntos
Colectomia/efeitos adversos , Ventrículos do Coração/fisiopatologia , Complicações Pós-Operatórias/diagnóstico , Taquicardia Ventricular/diagnóstico , Idoso , Neoplasias do Colo/cirurgia , Ecocardiografia , Cardioversão Elétrica , Eletrocardiografia , Bloqueio Cardíaco/cirurgia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Marca-Passo Artificial , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/terapia , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/terapia , Resultado do Tratamento
20.
Pain Physician ; 24(3): E327-E334, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33988954

RESUMO

BACKGROUND: Shoulder rotation has been shown to increase the acoustic window of ultrasound for thoracic epidural access. However, this effect of shoulder rotation has not yet been confirmed in clinical practice. OBJECTIVE: This study aimed to evaluate the effects of shoulder rotation on the thoracic epidural blockade in patients with acute or chronic pain in the thoracic region. STUDY DESIGN: Prospective crossover trial. SETTING: Pain clinic of our university in the Republic of Korea. METHODS: Forty patients aged 20 - 80 years with acute or chronic pain in the thoracic region who were scheduled to undergo thoracic epidural blockade more than twice. INTERVENTIONS: The patients underwent repeated fluoroscopy-guided thoracic epidural blockade via the paramedian approach in the lateral decubitus position either with or without shoulder rotation.The primary outcome measure was the attempt time to the confirmed spread of contrast. The number of attempts, total procedure time, vertical interpedicular distance, contrast spreading length, and complications were compared between the 2 positions. RESULTS: The median attempt times in the lateral decubitus and shoulder rotation positions were 138.8 and 132.5 seconds, respectively, and this difference was significant (P = 0.004). Compared with the lateral decubitus position, the shoulder rotation position was also associated with a significantly lower number of attempts (P = 0.03), shorter total procedure time (P < 0.001), and greater vertical interpedicular and contrast spreading distances (P < 0.001 and P = 0.02, respectively). LIMITATIONS: The operator in this study was not blinded to the patient groups. Other researchers observed the operator's procedure and evaluated and recorded the data in an attempt to overcome this bias. However, it was difficult to completely avoid the bias. Second, epidural blockade was performed at various levels (T3-11), and the anatomical features vary among thoracic spine levels. CONCLUSIONS: The study findings demonstrate the clinical benefits of the shoulder rotation position versus the lateral decubitus position in terms of successful epidural access during thoracic epidural blockade using the paramedian approach.


Assuntos
Anestesia Epidural , Ombro , Espaço Epidural/diagnóstico por imagem , Humanos , Estudos Prospectivos , Rotação , Ombro/diagnóstico por imagem
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