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1.
Ther Apher Dial ; 28(4): 505-510, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38453633

RESUMEN

INTRODUCTION: Rheocarna's therapeutic effect is associated with fibrinogen (Fib) and low-density lipoprotein cholesterol (LDL-C) adsorptive removal. This study aimed to retrospectively investigate the association between treatment volume (TV) and circulating blood volume (CBV) and the Fib removal rate (Fib-RR) and LDL-C-RR. METHODS: CBV and TV/CBV, cut-off value (CO value), and area under the receiver operating characteristic (ROC) curve (AUC) were calculated. The Fib-RR and LDL-C-RR at the midterm and end of treatment were compared. The groups were further categorized into three groups with TV/CBV lower than or higher than the CO value at the midterm and end (midterm/end; Group L: lower than/lower than CO; Group L/H: lower than/higher than CO; Group H: higher than/higher than CO), and the Fib-RR and LDL-RR of each group at the midterm and end were compared. RESULTS: ROC analysis revealed a TV of 1.480 times the BV as CO value, which showed a maximum Youden index predicting a Fib-RR of 20% (AUC: 0.828). Among the three groups, Group L and Group L/H demonstrated significantly higher Fib-RR and LDL-C-RR at the end of the study than in the midterm, while Group H exhibited no difference. CONCLUSION: The results reveal that a treatment volume of 1.5 times the circulating blood volume is a sufficient solute removal capacity in the Rheocarna-enabled cases.


Asunto(s)
Volumen Sanguíneo , LDL-Colesterol , Fibrinógeno , Humanos , Estudios Retrospectivos , Masculino , Femenino , LDL-Colesterol/sangre , Persona de Mediana Edad , Fibrinógeno/metabolismo , Anciano , Sustitutos del Plasma/administración & dosificación , Curva ROC
2.
CEN Case Rep ; 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38277067

RESUMEN

Occasionally, patients undergoing dialysis develop acute severe hypotension that requires interruption of dialysis within minutes of initiating every dialysis session. Although the underlying causes of recurrent intradialytic hypotension are evaluated extensively, including dialysis-associated allergic reactions or other possible causes, the definitive cause is sometimes missed. Dialysis is a life-sustaining procedure; therefore, prompt identification and management of the underlying cause of dialysis intolerance are crucial. Herein, we report three cases of patients undergoing dialysis who presented with hypereosinophilia-associated acute intradialytic hypotension. All three patients developed acute severe hypotension within minutes after the start of every dialysis session. The prescriptions for dialysis were changed, but episodes of intradialytic hypotension persisted. Pretreatment with methylprednisolone given intravenously before the dialysis session was also ineffective. All patients had hypereosinophilia (> 1500/µL) of different etiology. Eosinophil-lowering therapy with 0.5 mg/kg of prednisolone given orally daily was initiated, and all of them could restart dialysis without any hypotensive episodes within a few days. Our case report and literature review indicated that hypereosinophilia, regardless of its etiology, could result in severe acute hypotension shortly after the start of dialysis session. The oral administration of prednisolone daily was highly effective on hypereosinophilia-associated intradialytic hypotension, while pretreatment with intravenous corticosteroid therapy just before dialysis had no effect. Hypereosinophilia-associated acute intradialytic hypotension is an under-recognized condition; therefore, clinicians need to be aware of this clinical entity and initiate effective treatment strategies. We also provide a brief summary of previously published cases.

3.
CEN Case Rep ; 13(1): 53-58, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37244881

RESUMEN

Mass vaccination is the most important strategy to terminate the coronavirus disease 2019 (COVID-19) pandemic. Reports suggest the potential risk of the development of new-onset or relapse of minimal change disease (MCD) following COVID-19 vaccination; however, details on vaccine-associated MCD remain unclear. A 43-year-old man with MCD, who had been in remission for 29 years, developed nephrotic syndrome 4 days after receiving the third dose of the Pfizer-BioNTech vaccine. His kidney biopsy revealed relapsing MCD. Intravenous methylprednisolone pulse therapy followed by oral prednisolone therapy was administered, and his proteinuria resolved within 3 weeks. This report highlights the importance of careful monitoring of proteinuria after COVID-19 vaccination in patients with MCD, even if the disease is stable and no adverse events occurred during previous vaccinations. Our case report and literature review of COVID-19 vaccine-associated MCD indicated that MCD relapse tends to occur later after vaccination and slightly more often following the second and subsequent vaccine doses than new-onset MCD.


Asunto(s)
COVID-19 , Nefrosis Lipoidea , Masculino , Humanos , Adulto , Vacunas contra la COVID-19/efectos adversos , COVID-19/prevención & control , Nefrosis Lipoidea/diagnóstico , Nefrosis Lipoidea/tratamiento farmacológico , Nefrosis Lipoidea/etiología , Vacunación/efectos adversos , Enfermedad Crónica , Proteinuria , ARN Mensajero
4.
Kobe J Med Sci ; 69(2): E57-E63, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37661704

RESUMEN

BACKGROUND: Immunoglobulin A vasculitis is a systemic form of vasculitis that predominantly affects children. Factor XIII activity is decreased in some cases, and several reports have shown an association between abdominal pain and decreased factor XIII activity. However, the clinical significance of decreased factor XIII activity in pediatric immunoglobulin A vasculitis has not been fully elucidated. This study aimed to identify the association between factor XIII activity and the clinical course of pediatric patients with immunoglobulin A vasculitis. METHODS: Forty-four pediatric patients, admitted to Kita-Harima Medical Center with a clinical diagnosis of immunoglobulin A vasculitis between October 1, 2013 and September 30, 2022, were retrospectively reviewed, and 22 patients were analyzed. The patients' background characteristics and clinical course were compared between the normal and decreased factor XIII activity (<70%) groups. RESULTS: The group with decreased factor XIII activity showed a significantly increased duration of hospitalization (14 [6-36] vs. 7 [5-13] days, p = 0.01), total glucocorticoid dose (prednisolone 22.7 [4.9-55.5] vs. 10.1 [3.4-19.6] mg/kg, p = 0.02), and duration of glucocorticoid administration (19 [4-85] vs. 10 [3-15] days, p = 0.03). Correlational analyses showed that these three parameters were negatively correlated with factor XIII activity. CONCLUSIONS: Factor XIII activity was negatively correlated with the duration of hospitalization, total glucocorticoid dose, and duration of glucocorticoid administration. Factor XIII activity is not only associated with abdominal symptoms but also may be a marker to predict the overall trajectory of acute-phase treatment in pediatric patients with immunoglobulin A vasculitis.


Asunto(s)
Factor XIII , Vasculitis , Humanos , Niño , Glucocorticoides/uso terapéutico , Estudios Retrospectivos , Vasculitis/tratamiento farmacológico , Inmunoglobulina A , Progresión de la Enfermedad
5.
Ther Apher Dial ; 27(6): 1017-1022, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37589198

RESUMEN

INTRODUCTION: Chronic limb-threatening ischemia (CLTI) is a clinical syndrome defined by peripheral arterial disease (PAD) combined with rest pain, gangrene, or leg ulceration for longer than two weeks resulting in lower extremity amputation. In recent years, low-density lipoprotein apheresis (LDL-A) has been implemented for PAD treatment. However, it has not been possible to ensure insurance coverage for patients with lower LDL levels than 140 mg/dL under cholesterol-lowering drugs. Rheocarna is a novel adsorption-type blood purification device for the treatment of CLTI by adsorbing LDL and fibrinogen (Fib) that is not constrained by hypercholesterolemia and is not amenable to or nonresponsive to revascularization surgery. The only requirements for use are that the blood flow rate increases up to 200 mL/min gradually. METHODS: To evaluate the applicability of this treatment procedure, we compared the removal rates of Fib and LDL following Rheocarna therapy using various blood treatment volumes (6, 10.5, and 19.5 L). RESULTS: Fib and LDL removal rates were about 20% and 15%-25% per treatment, with no significant differences between treatment volumes. Following treatment with Rheocarna, blood pressure tends to decrease at first, which later increases, and the higher the treatment volume, the longer the time of low blood pressure tended to be. CONCLUSION: Although no significant difference was found in the removal rate of Fib and LDL in response to increase volume to 6 L or beyond in this study, the 6 L volume is considered effective enough for the removal of Fib and LDL.


Asunto(s)
Eliminación de Componentes Sanguíneos , Hipercolesterolemia , Enfermedad Arterial Periférica , Humanos , Isquemia Crónica que Amenaza las Extremidades , Adsorción , Hipercolesterolemia/terapia , Eliminación de Componentes Sanguíneos/métodos , Enfermedad Arterial Periférica/terapia , Resultado del Tratamiento , Isquemia/terapia
6.
Dent Mater J ; 42(4): 591-597, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37271539

RESUMEN

This study evaluated the effect of tricalcium phosphate-containing fluoride varnish on the prevention of root caries using an in-air micro-proton induced X-ray/gamma-ray emission system and microcomputed tomography. Either fluoride varnish (FV) or tricalcium phosphate-containing fluoride varnish (WV) was applied to root dentin, whereas dentin without varnish were considered controls. After immersion in saline, dentin sections were prepared, and concentration of fluoride ion was measured. These specimens were demineralized, and the mineral loss was measured. Caries inhibition in sound and demineralized dentin was observed in both FV and WV groups compared to the control group. Significantly low mineral loss was found especially in the demineralized dentin, which is probably due to the combination effect of calcium and fluoride ions at a concentration range of 100,000 ppm, as supplied by the varnish. The use of calcium-containing fluoride varnish, especially in demineralized dentin, is effective in arresting initial dentin caries.


Asunto(s)
Caries Dental , Fluoruros , Humanos , Fluoruros/farmacología , Caries Dental/prevención & control , Cariostáticos , Fluoruros Tópicos/farmacología , Calcio , Microtomografía por Rayos X , Minerales/farmacología , Dentina , Fluoruro de Sodio/farmacología
7.
J Funct Biomater ; 14(3)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36976095

RESUMEN

This study aimed to use an in-air micro-particle-induced X-ray/gamma emission (in-air µPIXE/PIGE) system to evaluate tooth-bound fluoride (T-F) in dentin following the application of fluoride-containing tooth-coating materials. Three fluoride-containing coating materials (PRG Barrier Coat, Clinpro XT varnish, and Fuji IX EXTRA) and a control were applied to the root dentin surface of human molars (n = 6, total 48 samples). Samples were stored in a remineralizing solution (pH 7.0) for 7 or 28 days and then sectioned into two adjacent slices. One slice of each sample was immersed in 1M potassium hydroxide (KOH) solution for 24 h and rinsed with water for 5 min for the T-F analysis. The other slice did not undergo KOH treatment and was used to analyze the total fluoride content (W-F). The fluoride and calcium distributions were measured in all the slices using an in-air µPIXE/PIGE. Additionally, the amount of fluoride released from each material was measured. Clinpro XT varnish demonstrated the highest fluoride release among all the materials and tended to show high W-F and T-F and lower T-F/W-F ratios. Our study demonstrates that a high fluoride-releasing material shows high fluoride distribution into the tooth structure and low conversion from fluoride uptake by tooth-bound fluoride.

8.
Polymers (Basel) ; 15(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36679346

RESUMEN

The development in the crystal structure analysis of synthetic polymers using the hybridized combination of wide-angle X-ray and neutron diffraction (WAXD and WAND, respectively) techniques has been reviewed with many case studies performed by the authors. At first, the technical development was reviewed, in which the usage of high-energy synchrotron X-ray source was emphasized for increasing the total number of the observable diffraction peaks, and several examples were introduced. Secondly, the usage of the WAND method was introduced, in which the successful extraction of hydrogen atomic positions was described. The third example is to show the importance for the hybrid combination of these two diffraction methods. The quantitative WAXD data analysis gave the crystal structures of at-poly(vinyl alcohol) (at-PVA) and at-PVA-iodine complex. However, the thus-proposed structure models were found not to reproduce the observed WAND data very much. The reason came from the remarkable difference in the atomic scattering powers of the constituting atomic species between WAXD and WAND phenomena. The introduction of statistical disorder solved this serious problem, which reproduced both of the observed WAXD and WAND data consistently. The more systematic combination of WAXD and WAND methods, or the so-called X-N method, was applied also to the quantitative evaluation of the bonded electron density distribution along the skeletal chains, where the results about polydiacetylene single crystals were presented as the first successful study. Finally, the application of WAND technique in the trace of structural changes induced under the application of external stress or temperature was described. The future perspective is described for the development of structural science of synthetic polymers on the basis of the combined WAXD/WAND techniques.

9.
J Funct Biomater ; 13(4)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36412887

RESUMEN

Several desensitizers routinely used clinically for dentin hypersensitivity are expected to inhibit demineralization. This study aimed to evaluate the effectiveness of sealing materials in inhibiting demineralization and increasing fluorine (F) uptake by acid-treated root surfaces. Five noncarious extracted human teeth were used to produce specimens. Three different fluoride-containing materials, namely "MS Coat F" (MS), "MS Coat Hys Block Gel" (HS), and CTX2 Varnish (FV), were used herein. Each material was applied to the demineralized root surface. Single sections were obtained from each specimen. All surfaces of each specimen, except the polished surface, were covered with wax and immersed in an automatic pH cycling system for 2 weeks. Fluorine and calcium distributions in the carious lesions of each specimen were evaluated using proton-induced gamma emission (PIGE) and X-ray (PIXE) techniques, respectively. Dentin demineralization was analyzed using transverse microradiography (TMR) before and after pH cycling. µPIXE/PIGE analysis demonstrated that all sample groups showed increased fluoride uptake on the root surface. TMR analysis revealed that both HS and FV showed significantly lower integrated mineral loss values than the control group. All three samples demonstrated a tendency towards increased fluoride uptake from fluoride-containing hypersensitivity desensitizers and a demineralization inhibition effect on root dentin.

10.
Nanomaterials (Basel) ; 12(8)2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35457999

RESUMEN

Despite recent advances in bonding restorations, which are the basis of restorative dentistry, secondary caries are still able to form. Previously, a novel fluoride-containing zinc and copper (ZCF) nanocomposite was introduced to prevent the formation of caries due to its antibacterial activity. In this study, we studied the impact of ZCF nanoparticles on the adhesive strength of bonding restorations through micro-tensile bond strength (µTBS) testing. The impact of antibacterial and matrix metalloproteinase (MMP) inhibitors on the nanoparticles was also examined. The nanocomposites were prepared using a simple one-step homogeneous co-precipitation method at a low temperature. A self-etch adhesive was applied to 10 extracted caries-free human molars with (test group) and without (control group) the ZCF nanoparticles. This was followed by composite resin build-up and µTBS testing, MMP activity assays, and evaluation of the antibacterial effects. The results showed no significant differences in the µTBS between the ZCF and the control groups. However, the ZCF exhibited a significant inhibitory effect against MMP-2, MMP-8, and MMP-9, in addition to an antibacterial effect on Streptococcus mutans. Therefore, the present study demonstrated that the addition of ZCF nanoparticles to adhesive systems can result in MMP inhibition and antibacterial action while maintaining the mechanical properties of the bonding restorations.

11.
Sci Rep ; 11(1): 13367, 2021 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-34183748

RESUMEN

Cardiotocography records fetal heart rates and their temporal relationship to uterine contractions. To identify high risk fetuses, obstetricians inspect cardiotocograms (CTGs) by eye. Therefore, CTG traces are often interpreted differently among obstetricians, resulting in inappropriate interventions. However, few studies have focused on quantitative and nonbiased algorithms for CTG evaluation. In this study, we propose a newly constructed deep neural network model (CTG-net) to detect compromised fetal status. CTG-net consists of three convolutional layers that extract temporal patterns and interrelationships between fetal heart rate and uterine contraction signals. We aimed to classify the abnormal group (umbilical artery pH < 7.20 or Apgar score at 1 min < 7) and the normal group from CTG data. We evaluated the performance of the CTG-net with the F1 score and compared it with conventional algorithms, namely, support vector machine and k-means clustering, and another deep neural network model, long short-term memory. CTG-net showed the area under the receiver operating characteristic curve of 0.73 ± 0.04, which was significantly higher than that of long short-term memory. CTG-net, a quantitative and automated diagnostic aid system, enables early intervention for putatively abnormal fetuses, resulting in a reduction in the number of cases of hypoxic injury.


Asunto(s)
Cardiotocografía/métodos , Frecuencia Cardíaca Fetal/fisiología , Algoritmos , Puntaje de Apgar , Femenino , Humanos , Concentración de Iones de Hidrógeno , Recién Nacido , Redes Neurales de la Computación , Embarazo , Contracción Uterina/fisiología
12.
Dent Mater J ; 40(5): 1142-1150, 2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34024882

RESUMEN

This study employed an in-air micro-proton-induced X-ray/gamma-ray emission system to assess the effectiveness of fluoride-containing materials (FCMs) incorporating calcium in preventing root caries. Dentin surfaces of human third molars were coated with one of three FCMs: fluoride-releasing glass-ionomer cement (F7) and experimental materials in which half (P1) or all (P2) of the strontium in F7 was replaced with calcium. Dentin without FCM coating served as the control. Specimens were immersed in saline at 37°C for 1 month, sectioned, and then demineralized. Calcium loss after demineralization was lower in the Ca-substituted groups than in the Ca-unsubstituted groups (p<0.05). Calcium loss was negatively correlated with fluoride uptake (p<0.01). In the F7, P1, and P2 groups, the retraction of the dentin surface was significantly suppressed as compared with the control group. FCMs incorporating calcium improved the acid resistance of root dentin and could help prevent root caries.


Asunto(s)
Fluoruros , Desmineralización Dental , Calcio , Dentina , Humanos , Protones , Rayos X
13.
Ther Apher Dial ; 25(4): 425-431, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33887113

RESUMEN

Plasma volume (PV) variation during therapeutic apheresis (TA) (such as plasma exchange [PE] and selective PE using albumin solution as replacement solution or immunoadsorption plasmapheresis) has been considered to be unignorable. It changes the concentration of the target molecule and might impact its removal rate (RR.) This study aimed to evaluate the effects of PV variation on the calculation of the RR of fibrinogen and immunoglobulin by categorizing the hematocrit (Ht) change during TA into two patterns, that is, increased group and decreased group. In all modalities of TA, the Ht level frequently changed during apheresis sessions. In calculating RR, RR calculated with Ht adjustment was significantly higher than that calculated without adjustment in the increased group and significantly lower than it in the decreased group. Therefore, RR might have been underestimated in the increased group and overestimated in the decreased group when RR was calculated without Ht adjustment. Ht adjustment is suggested to be crucial in calculating RR in TA.


Asunto(s)
Eliminación de Componentes Sanguíneos/métodos , Fibrinógeno , Hematócrito , Inmunoglobulinas/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Volumen Plasmático , Estudios Retrospectivos
14.
Sci Rep ; 11(1): 5759, 2021 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-33707701

RESUMEN

The receptor for advanced glycation end-products (RAGE) and the G protein-coupled angiotensin II (AngII) type I receptor (AT1) play a central role in cardiovascular diseases. It was recently reported that RAGE modifies AngII-mediated AT1 activation via the membrane oligomeric complex of the two receptors. In this study, we investigated the presence of the different directional crosstalk in this phenomenon, that is, the RAGE/AT1 complex plays a role in the signal transduction pathway of RAGE ligands. We generated Chinese hamster ovary (CHO) cells stably expressing RAGE and AT1, mutated AT1, or AT2 receptor. The activation of two types of G protein α-subunit, Gq and Gi, was estimated through the accumulation of inositol monophosphate and the inhibition of forskolin-induced cAMP production, respectively. Rat kidney epithelial cells were used to assess RAGE ligand-induced cellular responses. We determined that RAGE ligands activated Gi, but not Gq, only in cells expressing RAGE and wildtype AT1. The activation was inhibited by an AT1 blocker (ARB) as well as a RAGE inhibitor. ARBs inhibited RAGE ligand-induced ERK phosphorylation, NF-κB activation, and epithelial-mesenchymal transition of rat renal epithelial cells. Our findings suggest that the activation of AT1 plays a central role in RAGE-mediated cellular responses and elucidate the role of a novel molecular mechanism in the development of cardiovascular diseases.


Asunto(s)
Membrana Celular/metabolismo , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo , Animales , Células CHO , Cricetulus , Transición Epitelial-Mesenquimal , Proteínas de Unión al GTP/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Humanos , Ligandos , Unión Proteica , Ratas , Albúmina Sérica Bovina/metabolismo , Transducción de Señal , Transgenes
15.
Dent Mater J ; 40(3): 736-742, 2021 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-33518692

RESUMEN

The purpose of this study was to assess the effects of titanium fluoride (TiF4) concentration and pH on fluoride distribution and demineralization of root dentin surfaces. Concentrations of 0.1%, 1%, and 2% TiF4 (pH 1), 1% TiF4 solution adjusted to pH 4, 5, 6, and 1.35% sodium fluoride (NaF) solution were applied to root dentin surfaces. Each specimen was subjected to pH cycling (pH: 4.5-7.0) for 4 weeks. Lesion depth and calcium, fluorine, and titanium distribution were then evaluated. Our limited study indicates that lesion depth and fluorine and titanium distribution in dentin depend on the concentration of a TiF4 solution. We also found that a 1% TiF4 solution adjusted to a pH 4-6 can reduce demineralization as effectively as a similar concentration of NaF.


Asunto(s)
Fluoruros , Desmineralización Dental , Cariostáticos , Dentina , Humanos , Concentración de Iones de Hidrógeno , Fluoruro de Sodio , Titanio , Desmineralización Dental/prevención & control
16.
Case Rep Pediatr ; 2020: 8889827, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33194239

RESUMEN

BACKGROUND: Kawasaki disease (KD) is typically characterized by fever, oral cavity erythematous changes, bilateral bulbar conjunctival injection, skin rash, erythema and edema of the hands and feet, and cervical lymphadenopathy. Some atypical patients with KD initially develop cervical and pharyngeal cellulitis; however, an initial presentation with inguinal cellulitis is extremely rare. In addition, to our knowledge, no report has documented the cytokine profile in a KD patient with cellulitis. Case presentation. A previously healthy 8-year-old Japanese girl was hospitalized following a 2-day history of fever and a 5-day history of pain and erythema in the left inguinal region. She was diagnosed with bacterial inguinal cellulitis and was administered antibiotics. The next day, a polymorphous rash emerged on her trunk. After 3 days of antibiotics, however, her fever continued and the cellulitis had spread over the entire lower abdomen. Simultaneously, the bilateral bulbar conjunctival injection without exudate became more prominent and her lips became erythematous. In addition, erythematous changes on her palms appeared a few hours later, which led to the diagnosis of KD. Since she had a high risk score that predicted no response to initial intravenous immunoglobulin (IVIG) at the initiation of treatment, she was treated with IVIG, intravenous prednisolone (PSL), and oral aspirin. The KD symptoms improved the next day, but the cellulitis did not completely resolve until 2 months after discharge. The patient's serum cytokine profile at admission had an IL-6 dominant pattern which was consistent with that of patients with KD despite her initial lack of KD symptoms, and the pattern observed at admission was sustained until IVIG and PSL administration. CONCLUSION: KD should be included in the differential diagnosis for patients presenting with inguinal cellulitis who are unresponsive to initial empiric antibiotics.

17.
J Phys Chem B ; 124(29): 6266-6277, 2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32560588

RESUMEN

Neurodegenerative diseases are usually characterized by plaques made of well-ordered aggregates of distinct amyloid proteins. Dissociating these very stable amyloid plaques is a critical clinical issue. In this study, we present a joint mid-infrared free electron laser experiment/nonequilibrium molecular dynamics simulation to understand the dissociation process of a representative example GNNQQNY fibril. By tuning the laser frequency to the amide I band of the fibril, the resonance takes place and dissociation is occurred. With the calculated and observed wide-angle X-ray scattering profiles and secondary structures before and after laser irradiation being identical, we can propose a dissociation mechanism with high confidence from our simulations. We find that dissociation starts in the core of the fibrils by fragmenting the intermolecular hydrogen bonds and separating the peptides and then propagates to the fibril extremities leading to the formation of unstructured expanded oligomers. We suggest that this should be a generic mechanism of the laser-induced dissociation of amyloid fibrils.


Asunto(s)
Amiloide , Péptidos , Trastornos Disociativos , Humanos , Rayos Láser , Estructura Secundaria de Proteína
18.
Mod Rheumatol ; 30(6): 975-981, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31612758

RESUMEN

Objective: Ultrasonography (US) is a useful tool for evaluating the activity of rheumatoid arthritis (RA) patients. As the systemic evaluation of many joints is time-consuming, a method to evaluate this activity with a smaller number of joints is needed. The aim of this study was to clarify whether the number of joints assessed may be reduced using patient-oriented joint selection.Methods: A total of 492 RA patients were recruited at Kyoto University Hospital. Bilateral metacarpophalangeal (MCP), (proximal) interphalangeal (PIP/IP), and wrist joints were evaluated by US. Gray scale and power Doppler imaging findings were scored by a 0-3 semi-quantitative method. Clinical assessments were performed by physicians who were blind to US results, and a questionnaire on subjective symptoms was collected from each patient.Results: The correlation between the US score of all 22 joints (US22) and patient-oriented painful joints (PtUS) or physician-oriented tender and/or swollen joints were moderate (Spearman's ρ = 0.435) and weak (ρ = 0.383), respectively. These correlations were weaker than that between the total US score of 5 preselected joints (unilateral 2MCP, 3MCP, 2PIP, 3PIP, and the wrist) and US22 (ρ = 0.813). However, when focusing on patients whose painful joints were 5 and more, the correlation between PtUS and US22 was markedly stronger (ρ = 0.757).Conclusion: Patient-oriented joint selection reflected actual joint inflammation to some extent. However, excessive reductions in the number of joints assessed need to be avoided even if patients do not have arthralgia because of the potential for underestimations.


Asunto(s)
Artralgia/diagnóstico por imagen , Artritis Reumatoide/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Adulto , Anciano , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Articulación de la Muñeca/diagnóstico por imagen
19.
Polymers (Basel) ; 11(8)2019 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-31390825

RESUMEN

Time-resolved simultaneous measurements of wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) (and FTIR spectra) were performed for various kinds of crystalline polymers in isothermal melt-crystallization processes, from which the common features of the structural evolution process as well as the different behaviors intrinsic to the individual polymer species were extracted. The polymers targeted here were polyethylene, isotactic polypropylene, polyoxymethylene, aliphatic nylon, vinylidene fluoride copolymer, trans-polyisoprene, and poly(alkylene terephthalate). A universal concept of the microscopically viewed structural evolution process in isothermal crystallization may be described as follows: (i) the small domains composed of locally regular but more or less disordered helical chain segments are created in the melt (this important information was obtained by the IR spectral data analysis); (ii) these domains grow larger as the length and number of more regular helical segments increase with time; (iii) the correlation among the domains becomes stronger and they approach each other; and (iv) they merge into the stacked lamellar structure consisting of the regularly arranged crystalline lattices. The inner structure of the domains is different depending on the polymer species, as known from the IR spectral data.

20.
Mol Cancer Ther ; 18(8): 1366-1373, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31092564

RESUMEN

First- and second-generation EGFR tyrosine kinase inhibitors (TKI) are effective clinical therapies for patients with non-small cell lung cancer (NSCLC) harboring EGFR-activating mutations. However, almost all patients develop resistance to these drugs. The EGFR T790M mutation of EGFR is the most predominant mechanism for resistance. In addition, activation of AXL signaling is one of the suggested alternative bypassing pathways for resistance to EGFR-TKIs. Here, we report that naquotinib, a pyrazine carboxamide-based EGFR-TKI, inhibited EGFR with activating mutations, as well as T790M resistance mutation while sparing wild-type (WT) EGFR. In in vivo murine xenograft models using cell lines and a patient-derived xenograft model, naquotinib induced tumor regression of NSCLC with EGFR-activating mutations with or without T790M resistance mutation, whereas it did not significantly inhibit WT EGFR signaling in skin. Furthermore, naquotinib suppressed tumor recurrence during the treatment period of 90 days. In addition, unlike erlotinib and osimertinib, naquotinib inhibited the phosphorylation of AXL and showed antitumor activity against PC-9 cells overexpressing AXL in vitro and in vivo Our findings suggest that naquotinib has therapeutic potential in patients with NSCLC with EGFR-activating mutations, T790M resistance mutation, and AXL overexpression.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Mutación , Piperazinas/farmacología , Piperidinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas/genética , Pirazinas/farmacología , Pirrolidinas/farmacología , Proteínas Tirosina Quinasas Receptoras/genética , Animales , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Receptores ErbB/genética , Receptores ErbB/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Ratones , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Tirosina Quinasa del Receptor Axl
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