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Initial studies on the immunogenicity of SARS-CoV-2 (CoV-2) S glycoprotein ("spike") as a protein subunit vaccine suggested sub-optimal efficacy in mammals. Although protein engineering efforts have produced CoV-2 spike protein sequences with greatly improved immunogenicity, additional strategies for improving the immunogenicity of CoV-2 protein subunit vaccines are scaffolding and the use of adjuvants. Comparisons of the effectiveness of engineered protein-only and engineered protein-nanoparticles vaccines have been rare. To explore this knowledge gap, we inoculated mice with two doses of either sequence-optimized trimeric spike protein or one of several sequence-optimized spike nanoparticles. We measured their immune response up to two months after the first dose. We also measured the immune response and protection against live virus in hamsters inoculated with either sequence-optimized trimeric spike protein or a liposome-based sequence-optimized spike nanoparticle. We found that in the presence of adjuvant, the antibody and neutralization titers elicited by spike-nanoparticles were not significantly greater than those elicited by spike-only in mice, even at doses as low as 0.1 µg/animal. Hamsters vaccinated with spike-only or spike-nanoparticles were equally protected from live virus one month after their first inoculation. These results suggest that sequence-optimized protein subunit vaccines in the form of individual prefusion-stabilized trimers can be as effective in improving immunogenicity as scaffolded forms.
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Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Nanopartículas , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Vacunas de Subunidad , Animales , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Nanopartículas/química , Ratones , Cricetinae , Glicoproteína de la Espiga del Coronavirus/inmunología , SARS-CoV-2/inmunología , Anticuerpos Antivirales/inmunología , Vacunas de Subunidad/inmunología , COVID-19/prevención & control , COVID-19/inmunología , Anticuerpos Neutralizantes/inmunología , Femenino , Ingeniería de Proteínas/métodos , Inmunogenicidad Vacunal , Ratones Endogámicos BALB C , Modelos Animales de Enfermedad , HumanosRESUMEN
Aspergillus-specific antibodies are diagnostic indicators of allergic bronchopulmonary aspergillosis (ABPA) and chronic pulmonary aspergillosis (CPA). Tests for detecting Aspergillus-specific antibodies were not used clinically in Japan, and the production of the Aspergillus precipitin test was discontinued. Thus, alternative tests for diagnosing aspergillosis are urgently needed. We retrospectively evaluated 64 patients with suspected ABPA and CPA who underwent precipitin antibody testing. Serum Aspergillus IgG levels were measured and compared using the Bordier Aspergillus fumigatus ELISA and the Platelia Aspergillus IgG (Bio-Rad) kits. Of the participants, 18 were diagnosed with CPA, and 8 were diagnosed with ABPA. Both the Bordier and Bio-Rad kits showed high sensitivity and specificity for CPA and ABPA. The area under the receiver operating characteristic curves for the Bordier and Bio-Rad kits were 0.97 and 0.95, respectively, for CPA, and 0.89 and 0.91, respectively, for ABPA. In contrast to the Bordier kit, the Bio-Rad kit showed relatively low anti-Aspergillus IgG levels and lower sensitivity to non-fumigatus Aspergillus infections. The Aspergillus-specific IgG ELISA tests showed sufficient diagnostic accuracy. Therefore, these assays are recommended as alternatives to the precipitin kit for diagnosing aspergillosis in clinical settings in Japan.
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Anticuerpos Antifúngicos , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G , Aspergilosis Pulmonar , Sensibilidad y Especificidad , Humanos , Estudios Retrospectivos , Inmunoglobulina G/sangre , Anticuerpos Antifúngicos/sangre , Masculino , Femenino , Persona de Mediana Edad , Anciano , Aspergilosis Pulmonar/diagnóstico , Aspergilosis Pulmonar/inmunología , Adulto , Ensayo de Inmunoadsorción Enzimática/métodos , Japón , Aspergillus/inmunología , Anciano de 80 o más Años , Técnicas para Inmunoenzimas/métodos , Aspergilosis Broncopulmonar Alérgica/diagnóstico , Aspergilosis Broncopulmonar Alérgica/inmunología , Aspergilosis Broncopulmonar Alérgica/sangre , Aspergillus fumigatus/inmunología , Curva ROCRESUMEN
We estimated the seroprevalence of anti-SARS-COV-2 IgG in different island groups in Okinawa. A cross-sectional sero-survey was repeated in three periods between July 2020 and February 2021. A total of 2683 serum samples were collected from six referral medical centers, each covering a separate region in Okinawa. In the main island, the seroprevalence was 0.0% (0/392, 95% CI: 0.0-0.9), 0.6% (8/1448, 0.2-1.1), and 1.4% (8/582, 0.6-2.7) at the 1st, 2nd, and 3rd sero-survey, respectively. In the remote islands, the seroprevalence was 0.0% (0/144, 95% CI: 0.0-2.5) and 1.6% (2/123, 0.2-5.8) at the 2nd and 3rd survey, respectively. The case detection ratio was 2.7 (95% CI: 1.3-5.3) in the main island and 2.8 (0.7-11.1) in the remote islands during the 3rd survey. The case detection ratio was the highest in people aged 20-29 years (8.3, 95% CI: 3.3-21.4) in the main island and in those aged 50-59 years (14.1, 2.1-92.7) in the remote islands, suggesting under-reporting of clinical cases by the surveillance system in these subgroups. A sero-survey during an emerging infectious disease epidemic can be useful for validating the reliability of the surveillance system by providing the case detection ratio.
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Predicting the mechanical properties of polymer materials using machine learning is essential for the design of next-generation of polymers. However, the strong relationship between the higher-order structure of polymers and their mechanical properties hinders the mechanical property predictions based on their primary structures. To incorporate information on higher-order structures into the prediction model, X-ray diffraction (XRD) can be used. This study proposes a strategy to generate appropriate descriptors from the XRD analysis of the injection-molded polypropylene samples, which were prepared under almost the same injection molding conditions. To this end, first, Bayesian spectral deconvolution is used to automatically create high-dimensional descriptors. Second, informative descriptors are selected to achieve highly accurate predictions by implementing the black-box optimization method using Ising machine. This approach was applied to custom-built polymer datasets containing data on homo- polypropylene and derived composite polymers with the addition of elastomers. Results show that reasonable accuracy of predictions for seven mechanical properties can be achieved using only XRD.
This study proposes a strategy to generate appropriate descriptors, which realize highly accurate predictions of mechanical properties via machine learning from the XRD analysis of the molded polypropylene samples.
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Background: Secondary anterior cruciate ligament (ACL) injury is a complication of ACL reconstruction (ACLR), which may result from altered neuromuscular control affecting anticipatory postural adjustments (APAs) and compensatory postural adjustments (CPAs) required for maintaining balance during movement. However, it remains unclear how APAs and CPAs differ in single-leg landings post-ACLR compared to healthy subjects. Purpose: The purpose of this study was to clarify the differences in muscle activities of APAs and CPAs, lower limb kinematics, and kinetics between athletes with a history of ACLR and healthy athletes during single-leg landing. Study design: Cross-sectional study. Methods: Eighteen female athletes were recruited and divided into ACLR (n = 9) and control groups (n = 9). The experimental task involved a single-leg landing from a 30 cm box. Joint angles and moments were determined using a 3-dimensional motion analysis system, while muscle activity was assessed using surface electromyography. Analysis intervals were divided into two phases: the APA phase (-150 ms to 50 ms) and the CPA phase (50 ms to 250 ms), with initial contact (0 ms) as the reference point. Muscle activity onset time was defined as the time when the baseline exceeded by the sum of mean values and 2 standard deviations. Results: No significant differences were observed in muscle activity or onset time between the ACLR and control groups. However, an increased hip external rotation moment was observed during the CPA phase in the ACLR group. Conclusion: These findings suggest that APAs and CPAs of athletes who returned to sports more than 1 year post-ACLR may be similar. The increased hip external rotation moment in the ACLR group during the CPA phase could represent a specific compensatory strategy to decrease the hip internal rotation angle post-ACLR. Level of Evidence: III.
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In case that met several indication criteria with 4 or more rib fractures, we performed surgical stabilization of multiple fractured ribs using a plate and screw system( Super FIXORB MX) that was made of uncalcined hydroxyapatite (u-HA)/poly-L-lactic acid (PLLA) composite material with excellent bioactivity and absorbability. We report our clinical experience of 7 cases in which this device was used. Although there is still room for further consideration of the technique and the strength of the device itself, computed tomography( CT) images taken 9 months after surgery showed that the fixative device was almost assimilated with the bone at the fracture repair site in cases where fixation was successful.
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Durapatita , Fijación Interna de Fracturas , Fracturas de las Costillas , Humanos , Fracturas de las Costillas/cirugía , Fracturas de las Costillas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Femenino , Fijación Interna de Fracturas/métodos , Adulto , Anciano , Poliésteres , Fracturas Múltiples/cirugía , Fracturas Múltiples/diagnóstico por imagen , Implantes Absorbibles , Placas Óseas , PolímerosRESUMEN
Purpose: To evaluate international prostate symptom score and urinary quality of life in patients with prostate cancer who underwent low-dose-rate brachytherapy, and to identify lower urinary tract symptoms that must be improved to enhance post-operative urinary quality of life and factors associated with lower urinary tract symptoms. Material and methods: This study included 193 patients who underwent low-dose-rate brachytherapy alone (145 Gy). Importance-performance analysis was conducted to identify lower urinary tract symptoms that should be prioritized to improve urinary quality of life. Association between lower urinary tract symptom scores and each factor was investigated. Receiver operating characteristic curve analysis was used to evaluate dosimetric parameters related to lower urinary tract symptom score to predict an average score of ≥ 3. Cut-off values were determined. Results: One to nine months post-implantation was a period of significantly increased urinary quality of life scores compared with baseline (p < 0.05 each). The importance-performance analysis conducted for 1-9 months revealed that frequency, nocturia, and weak stream required improvement. Multivariate analysis showed that each lower urinary tract symptom score presented a significant association with its baseline value (p < 0.001 each, positive correlation). Frequency, incomplete emptying, urgency, and straining scores were significantly associated with prostate volume, whereas weak stream and intermittency scores were associated with dose covering 90% of the prostate and dose covering 90% of the urethra, respectively (p < 0.05 each, positive correlations). Cut-off values for these doses were 167.01 Gy and 136.84 Gy, respectively. Conclusions: This study highlights the importance of prioritizing specific lower urinary tract symptoms for improvement in post-operative urinary quality of life, and identifies the associated factors that can help in personalized treatment planning and goal-setting for better patient satisfaction.
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Vaccination is an important factor in public health. The recombinant bacillus Calmette Guérin (rBCG) vaccine, which expresses foreign antigens, is expected to be a superior vaccine against infectious diseases. Here, we report a new recombination platform in which the BCG Tokyo strain is transformed with nucleotide sequences encoding foreign protein fused with the MPB70 immunogenic protein precursor. By RNA-sequencing, mpb70 was found to be the most transcribed among all known genes of BCG Tokyo. Small oligopeptide, namely, polyhistidine tag, was able to be expressed in and secreted from rBCG through a process in which polyhistidine tag fused with intact MPB70 were transcribed by an mpb70 promoter. This methodology was applied to develop an rBCG expressing the receptor binding domain (RBD) of severe acute respiratory syndrome coronavirus 2. Immunoblotting images and mass spectrometry data showed that RBD was also secreted from rBCG. Sera from mice vaccinated with the rBCG showed a tendency of weak neutralizing capacity. The secretion was retained even after a freeze-drying process. The freeze-dried rBCG was administered to and recovered from mice. Recovered rBCG kept secreting RBD. Collectively, our recombination platform offers stable secretion of foreign antigens and can be applied to the development of practical rBCGs.
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Vacuna BCG , Mycobacterium bovis , Animales , Ratones , Vacuna BCG/genética , Tokio , Mycobacterium bovis/genética , Activación de Linfocitos , Ingeniería Genética , Vacunas SintéticasRESUMEN
Surgical resection of the infected lung with curative intent is the treatment of choice for lung abscesses that are difficult to control with medical treatment alone. However, lung resection is considered difficult in some cases. Herein, we report two cases of destroyed lungs with severe symptoms, for which palliative cavernostomy was performed instead of infected lung resection. Case 1 was a 45-year-old man who had granulomatosis with polyangiitis in both lungs. Steroid pulse and immunosuppression therapies were repeated, resulting in a huge, destroyed lung on the right side with chronic necrotizing bilateral aspergillosis, causing severe symptoms. Considering the bilateral spread and extension of the cavity lesions, cavernostomy was performed for the destroyed right lung. Case 2 was a 73-year-old woman who had undergone a left lower lobectomy for a metastatic lung tumor and developed a destroyed lung with severe symptoms in the residual left upper lobe caused by a non-tuberculous mycobacterial infection. Since a completion pneumonectomy with curative intent was considered too invasive for her poor general condition, cavernostomy was performed for the destroyed lung. Palliative operations significantly relieved the severe symptoms and improved the general conditions of these patients, enabling outpatient follow up.
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Aspergilosis , Absceso Pulmonar , Neoplasias Pulmonares , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Pulmón/cirugía , Aspergilosis/cirugía , Neumonectomía/métodos , Absceso Pulmonar/diagnóstico por imagen , Absceso Pulmonar/cirugía , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugíaRESUMEN
Purpose: In irradiating the prostate and pelvic lymph node regions, registration based on bony structures matches the pelvic lymph node regions but not necessarily the prostate position, and it is important to identify factors that influence prostate displacement. Therefore, we investigated factors influencing prostate displacement during volumetric modulated arc therapy after single-fraction high-dose-rate brachytherapy (HDR-BT) for prostate cancer and the trends in displacement for each fraction. Methods and Materials: Seventy patients who underwent pelvic volumetric modulated arc therapy of 46 Gy in the prone position 15 days after 13 Gy HDR-BT were included. Prostate displacement relative to bony structures was calculated using cone beam computed tomography. Systematic error (SE) and random error (RE) were evaluated in the right-left (RL), craniocaudal (CC), and anteroposterior (AP) directions. The association with clinical and anatomic factors on the planning computed tomography or magnetic resonance imaging was analyzed. Prostate volume change (PVC) was defined as the volume change at 2 days after HDR-BT. Displacement trends were individually examined from the first to 23rd fractions. Results: The mean SE in the RL, CC, and AP directions was -0.01 mm, -2.34 mm, and -0.47 mm, respectively. The root mean square of the RE in the RL, CC, and AP directions was 0.44 mm, 1.14 mm, and 1.10 mm, respectively. SE in the CC direction was independently associated with bladder volume (P = .021, t statistic = 2.352) and PVC (P < .001, t statistic = -8.526). SE in the AP direction was independently associated with bladder volume (P = .013, t statistic = -2.553), PVC (P < .001, t statistic = 5.477), and rectal mean area (P = .008, t statistic = 2.743). RE in the CC direction was independently associated with smoking (P = .035). RE in the AP direction was associated with PVC (P = .043). Gradual displacement caudally and posteriorly occurred during the irradiation period. Conclusions: Anatomic characteristics of the bladder, rectum, and prostate predict SE. Smoking and PVC predict RE. In particular, whether PVC is ≥140% affects setting internal margins.
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The close relationship between infectious diseases and iron metabolism is well known, but a more detailed understanding based on current knowledge may provide new insights into the diagnosis and treatment of infectious diseases, considering the growing threat of antibiotic-resistant bacteria. This study investigated adult patients with bloodstream infections, temporal changes, and relationships between blood levels of iron and related markers, including hepcidin and lipocalin-2 (LCN2). We included 144 samples from 48 patients (mean age 72 years, 50% male), with 30 diagnosed with sepsis. During the acute phase of infection, blood levels of hepcidin and LCN2 increased rapidly, whereas iron levels decreased, with values in 95.8% of cases below the normal range (40-188 µg/dL). Later, hepcidin and LCN2 decreased significantly during the recovery phase, and the decreased iron concentrations were restored. In the case of persistent inflammation, iron remained decreased. Acute LCN2 levels were significantly higher in patients with sepsis (p < 0.01). Hypoferremia induced by increased hepcidin would reduce iron in the environment of extracellular pathogens, and the increased LCN2 would inhibit siderophores, resulting in the prevention of the pathogen's iron acquisition in each manner during the acute phase of bloodstream infection.
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Enfermedades Transmisibles , Sepsis , Humanos , Masculino , Anciano , Femenino , Hepcidinas/metabolismo , Lipocalina 2/metabolismo , Hierro/metabolismo , Sideróforos/metabolismoRESUMEN
INTRODUCTION: Sports activity can affect balance ability, increasing injury risk. Single session of acute exercise can also alter cognitive function, potentially linked to balance ability. In this study, we examined the changes in cognitive function and static and dynamic balance abilities before and after the basketball game, and a dual-task was used to evaluate static balance ability. METHOD: We measured the rating of perceived exertion (RPE), static and dynamic balance ability, and cognitive function in 12 male university basketball players before and after basketball game. We compared the differences in each measurement before and after the game using a t-test and examined the correlation between RPE, cognitive function, and balance ability. RESULTS: We found RPE and cognitive function increased after the game. However, static balance ability in the dual-task and dynamic balance ability did not change before and after the game. Positive correlation found pre-RPE with SC-total and DO-locus length, and SEBT-ANT. Negative correlation found post-RPE with SEBT-PL, and positive correlation found ΔRPE with DO-peripheral area. DISCUSSION: To enhance post-game balance ability, it is crucial to assess pre-game RPE for each player. Also, the understanding game-induced load is imperative as high post-game RPE negatively affects static and dynamic balance ability. Therefore, game load management strategies must be employed to ensure optimal balance ability. CONCLUSION: Because RPE before and after a basketball game is related to balance ability after the game, it is important to understand the amount of load on the players.
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Baloncesto , Humanos , Masculino , Baloncesto/psicología , Ejercicio FísicoRESUMEN
Background: Lower neurocognitive function is a risk factor for anterior cruciate ligament (ACL) injury. However, the mechanism by which lower neurocognitive function increases the risk of ACL injury remains unclear. Purpose: To clarify the effect of differences in neurocognitive function on landing mechanics during a single-leg drop-jump landing motion followed by an unanticipated task. Study Design: Cross-sectional study. Methods: Fifteen collegiate female athletes were recruited (20.1 ± 1.3 years, 166.6 ± 7.3 cm, 60.6 ± 6.9 kg) and were divided into two groups (the high-performance (HP) group and the lower-performance (LP) group) using the median Symbol Digit Modalities Test (SDMT) score. Three-dimensional motion analysis was employed for the analysis during the experimental task of a single-leg drop-jump followed by an unanticipated landing task from a 30-cm high box. Joint angular changes of the trunk, pelvis, hip, and knee were calculated within the interval from initial contact (IC) to 40ms. Knee and hip moments were calculated as the maximum values within the interval from IC to 40ms. Surface electromyography data from key muscles were analyzed 50ms before and after IC. Independent t-tests were used to compare the effects of different neurocognitive function on the measurement items. Statistical significance was set at p < 0.05. Results: The SDMT score was significantly higher in HP group (HP: 77.9 ± 5.5; LP: 66.0 ± 3.4; p < 0.001). The LP group had a significantly greater trunk rotation angular change to the stance leg side (HP: 0.4 ± 0.8; LP: 1.2 ± 0.4; p = 0.020). There were no significant differences between the two groups in terms of joint moments, and muscle activities. Conclusion: Differences in neurocognitive function by SDMT were found to be related to differences in motor strategies of the trunk in the horizontal plane. Although trunk motion in the sagittal and frontal planes during single-leg drop-jump landing increases the ACL injury risk by affecting knee joint motion, the effect of trunk motion in the horizontal plane remains unclear. Level of Evidence: 3© The Authors.
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Great effort has been devoted to discovering the basis of A3G-Vif interaction, the key event of HIV's counteraction mechanism to evade antiviral innate immune response. Here we show reconstitution of the A3G-Vif complex and subsequent A3G ubiquitination in vitro and report the cryo-EM structure of the A3G-Vif complex at 2.8 Å resolution using solubility-enhanced variants of A3G and Vif. We present an atomic model of the A3G-Vif interface, which assembles via known amino acid determinants. This assembly is not achieved by protein-protein interaction alone, but also involves RNA. The cryo-EM structure and in vitro ubiquitination assays identify an adenine/guanine base preference for the interaction and a unique Vif-ribose contact. This establishes the biological significance of an RNA ligand. Further assessment of interactions between A3G, Vif, and RNA ligands show that the A3G-Vif assembly and subsequent ubiquitination can be controlled by amino acid mutations at the interface or by polynucleotide modification, suggesting that a specific chemical moiety would be a promising pharmacophore to inhibit the A3G-Vif interaction.
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VIH-1 , Productos del Gen vif del Virus de la Inmunodeficiencia Humana , Productos del Gen vif del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen vif del Virus de la Inmunodeficiencia Humana/metabolismo , VIH-1/fisiología , ARN/metabolismo , Antivirales/farmacología , Antivirales/metabolismo , Aminoácidos/metabolismo , Desaminasa APOBEC-3G/química , Citidina Desaminasa/genéticaRESUMEN
The Gram-negative anaerobe, Porphyromonas gingivalis, is known to be a pathogen associated with chronic periodontitis. P. gingivalis possesses virulence factors such as fimbriae and gingipain proteinases. Fimbrial proteins are secreted to the cell surface as lipoproteins. In contrast, gingipain proteinases are secreted into the bacterial cell surface via the type IX secretion system (T9SS). The transport mechanisms of lipoproteins and T9SS cargo proteins are entirely different and remain unknown. Therefore, using the Tet-on system developed for the genus Bacteroides, we newly created a conditional gene expression system in P. gingivalis. We succeeded in establishing conditional expression of nanoluciferase and its derivatives for lipoprotein export, of FimA for a representative of lipoprotein export, and of T9SS cargo proteins such as Hbp35 and PorA for representatives of type 9 protein export. Using this system, we showed that the lipoprotein export signal, which has recently been found in other species in the phylum Bacteroidota, is also functional in FimA, and that a proton motive force inhibitor can affect type 9 protein export. Collectively, our conditional protein expression method is useful for screening inhibitors of virulence factors, and may be used to investigate the role of proteins essential to bacterial survival in vivo.
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Proteínas Bacterianas , Porphyromonas gingivalis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Cisteína-Endopeptidasas Gingipaínas/metabolismo , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Péptido Hidrolasas/metabolismo , Lipoproteínas/genética , Lipoproteínas/metabolismo , Expresión Génica , Sistemas de Secreción Bacterianos/genéticaRESUMEN
High expression of low-density lipoprotein receptor-related protein 6 (LRP6), a key component of the Wnt/ß-catenin signaling pathway, is reported to be associated with malignant potential in some solid tumors including breast cancer and hepatocellular carcinoma. Few reports, however, have examined its function and clinical significance in colorectal cancers (CRC) demonstrating constitutive activation of Wnt signaling. Here, we compared the expression level and function of LRP6 in CRC with that of esophageal squamous cell carcinoma (ESCC) bearing few Wnt/ß-catenin pathway mutations. On immunohistochemical staining, high LRP6 expression was noted in three of 68 cases (4.4%), and high ß-catenin in 38 of 67 cases (56.7%) of CRC. High LRP6 expression was found in 21 of 82 cases (25.6%), and high ß-catenin expression in 29 of 73 cases (39.7%) of ESCC. In our in vitro studies, LRP6 knockdown hardly changed Wnt signaling activity in CRC cell lines with mutations in Wnt signaling downstream genes. In contrast, in ESCC cell lines without Wnt signaling-related mutations, LRP6 knockdown significantly decreased Wnt signaling activity. LRP6 function may depend on constitutive activation of Wnt signaling.
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Many members of the phylum Bacteroidota (formerly called Bacteroidetes) adhere to and move on solid surfaces. This type of bacterial motility is called gliding and does not involve the conventional bacterial motility machinery, such as flagella and pili. To understand the mechanism of gliding motility of some Bacteroidota bacteria such as a soil bacterium Flavobacterium johnsoniae and a marine bacterium Saprospira grandis, the gliding motility machines of these two bacteria have been analyzed by electron microscopy with negative staining. Here, we describe methods to directly observe the gliding motility machinery in Bacteroidota by transmission electron microscopy.
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Proteínas Bacterianas , Flavobacterium , Bacteroidetes , Fimbrias BacterianasRESUMEN
Many phylum Bacteroidetes bacteria are motile without either flagella or pili. These cells move on surfaces such as glass or agar, and a motor generates a propulsion force for the cells via a proton motive force across the cytoplasmic membrane. The gliding motility depends on the helical track of cell adhesin along the longer axis of the cell body. Here, we describe live-cell imaging of gliding motility under optical microscopy, as well as an immunofluorescent labeling method for visualizing helical trajectories.
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Proteínas Bacterianas , Microscopía , Proteínas Bacterianas/metabolismo , Adhesinas Bacterianas/metabolismo , Flavobacterium/metabolismo , Bacteroidetes/metabolismoRESUMEN
Many bacteria belonging to the phylum Bacteroidetes move on solid surfaces, called gliding motility. In our previous study with the Bacteroidetes gliding bacterium Flavobacterium johnsoniae, we proposed a helical loop track model, where adhesive SprB filaments are propelled along a helical loop on the cell surface. In this study, we observed the gliding cell rotating counterclockwise about its axis when viewed from the rear to the advancing direction of the cell and revealed that one labeled SprB focus sometimes overtook and passed another SprB focus that was moving in the same direction. Several electron microscopic analyses revealed the presence of a possible multi-rail structure underneath the outer membrane, which was associated with SprB filaments and contained GldJ protein. These results provide insights into the mechanism of Bacteroidetes gliding motility, in which the SprB filaments are propelled along tracks that may form a multi-rail system underneath the outer membrane. The insights may give clues as to how the SprB filaments get their driving force.
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Proteínas Bacterianas , Bacteroidetes , Proteínas Bacterianas/metabolismo , Bacteroidetes/metabolismoRESUMEN
PURPOSE: The purpose of this study was to analyze the patterns of failure in patients with glioblastoma multiforme (GBM) treated using chemoradiotherapy in the Standard radiotherapy (60 Gy/30 fractions; Standard) or Short course (40 Gy/15 fractions: Short). MATERIALS AND METHODS: Ninety-three consecutive patients with newly diagnosed glioblastoma treated at our hospital between April 2007 and December 2016, and 68 patients who could be followed up were included. All patients underwent surgical resection followed by radiotherapy with concurrent temozolomide. We retrospectively analyzed treatment outcomes and recurrence patterns. RESULTS: The median follow-up period of the surviving patients was 82.8 months (range: 46.0-158.9 months). Of the 68 patients, 58 patients (85%) had recurrences, 34 underwent the Standard and 24 Short course. The Standard course was seen in younger age groups and had a better Karnofsky performance status (KPS) than the Short course. The median survival time (MST) was 25.8 months for the Standard and 15.4 months with the Short in all cases. Standard course had significantly longer MST than the Short (p = 0.001) course. For recurrent cases only, there was no significant difference between Standard and Short courses in OS (p = 0.06). The recurrences occurred at the radiation fields alone (Standard/Short: 85%/83%), only at distant sites (Standard/Short: 12%/13%), and at both the radiation fields and distant sites (Standard/Short: 3%/4%). There was no significant difference in recurrence pattern and frequency between the two protocols (p = 0.11). CONCLUSIONS: Standard course tended to be significant in younger age groups and have a better KPS than the Short course; therefore, the Standard course has a longer OS, but the recurrence pattern of the Short course is similar to that of the Standard treatment.