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Thiopeptides make up a group of structurally complex peptidic natural products holding promise in bioengineering applications. The previously established thiopeptide/mRNA display platform enables de novo discovery of natural product-like thiopeptides with designed bioactivities. However, in contrast to natural thiopeptides, the discovered structures are composed predominantly of proteinogenic amino acids, which results in low metabolic stability in many cases. Here, we redevelop the platform and demonstrate that the utilization of compact reprogrammed genetic codes in mRNA display libraries can lead to the discovery of thiopeptides predominantly composed of nonproteinogenic structural elements. We demonstrate the feasibility of our designs by conducting affinity selections against Traf2- and NCK-interacting kinase (TNIK). The experiment identified a series of thiopeptides with high affinity to the target protein (the best KD = 2.1 nM) and kinase inhibitory activity (the best IC50 = 0.15 µM). The discovered compounds, which bore as many as 15 nonproteinogenic amino acids in an 18-residue macrocycle, demonstrated high metabolic stability in human serum with a half-life of up to 99 h. An X-ray cocrystal structure of TNIK in complex with a discovered thiopeptide revealed how nonproteinogenic building blocks facilitate the target engagement and orchestrate the folding of the thiopeptide into a noncanonical conformation. Altogether, the established platform takes a step toward the discovery of thiopeptides with high metabolic stability for early drug discovery applications.
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Aminoácidos , Peptídeos , Humanos , Peptídeos/química , Aminoácidos/química , Código Genético , RNA MensageiroRESUMO
Materials for Cs+ adsorption continue to be important for the treatment of various solutions. Metal-organic frameworks (MOFs) with large specific surface areas promise adsorption properties for various gases, vapors, and ions. However, the utilization of MOFs for alkali ion capture, specifically, Cs+ capture is still in its infancy. Herein, MOFs are hybridized with polyoxometalates (POMs) to study the effect of i) MOF type, ii) POM type, and iii) POM loading amounts on Cs+ capture. In particular, the composite of ZIF-8 and [α-PMo12O40]3- (PMo12/ZIF-8) adsorbed Cs+ ions effectively when compared to pristine ZIF-8. In addition, the reduction of Mo within the POM from MoVI to MoV by ascorbic acid during the Cs+ uptake process doubled the Cs+ uptake capacity of PMo12/ZIF-8. This observation can be attributed to the increased overall negative charge of the POM facilitating Cs+ uptake to compensate for the charge imbalance. Hybridization with other MOFs (MIL-101 and UiO-66) largely suppresses the Cs+ uptake, highlighting the importance of hydrophobicity in Cs+ capture. Furthermore, PMo12/ZIF-8 led to an outstanding Cs+ uptake (291.5 mg g-1) with high selectivity (79.6%) from quinary mixtures of alkali metal cations even among other representative porous materials (Prussian blue and zeolites).
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INTRODUCTION/AIMS: Concentric needle electromyography (CNEMG) is an essential examination for evaluating neuromuscular disorders, although pain is a drawback. Clustering Index (CI) method is a non-invasive quantitative analysis for surface electromyography (SEMG) that evaluates whether the signal area is clustered into the few large motor unit potentials (MUPs) or is evenly distributed. However, the diagnostic yield of the CI method in comparison with CNEMG is not known. In this study, we aimed to compare the sensitivity of the CI method with MUP parameters in CNEMG for diagnosing neurogenic or myogenic disorders. METHODS: We retrospectively identified patients for whom both SEMG and CNEMG were performed on the same tibialis anterior (TA) muscle. In CNEMG, seven MUP parameters were evaluated, including size index (SI) and revised size indices for neurogenic (rSIn) and myogenic (rSIm) disorders. RESULTS: Identified were 21 patients with neurogenic and 21 patients with myogenic disorders. Control data were constructed from 30 control subjects. The sensitivities of the CI method for the neurogenic and myogenic groups were 76% and 62%, respectively, which were not significantly different from MUP parameters, except for being significantly higher than those of amplitude and duration for myopathy (24%). Among MUP parameters, the sensitivities of rSIn (62%) and rSIm (57%) for myopathy were significantly higher than those of amplitude and duration. The CI method significantly correlated with the strength of the TA muscle in myopathy. DISCUSSION: The CI method, having comparable diagnostic yields to MUP parameters, is promising as a non-invasive diagnostic measure.
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The concept of attention in cognitive science encompasses a bidirectional nature: bottom-up attention based on the salience of sensory stimuli, and top-down attention, which involves voluntary control over aspects such as intensity, allocation, selectivity, and duration. Top-down attention is believed to be primarily realized through the frontal lobes that monitor on-going information processing. This monitoring helps detect situations requiring intervention and manipulates lower-level information processing systems as a part of executive functions.
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Atenção , Lobo Frontal , Humanos , Atenção/fisiologia , Lobo Frontal/fisiologia , Função Executiva/fisiologiaRESUMO
Atomic-resolution scanning transmission electron microscopy combined with 2D Gaussian fitting enables the accurate and precise identification of atomic column positions within a few picometers. The measurement performance significantly depends on the signal-to-noise ratio of the atomic columns. In areas with low signal-to-noise ratios, such as near surfaces, the measurement performance was lower than that of the bulk. However, previous studies evaluated the accuracy and precision only in bulk areas, underscoring the need for a method that quantitatively evaluates the accuracy and precision of each atomic column position with various signal-to-noise ratios. This study introduced Bayesian inference to assess the accuracy and precision of determining individual atomic column positions under various signals. We applied this method to simulated and experimental images and demonstrated its effectiveness in identifying statistically significant displacements, particularly near surfaces with signal degradation. The use of vector maps and kernel density estimate plots obtained from Bayesian inference provided a probabilistic understanding of the atom displacement. Therefore, this study highlighted the potential benefits of Bayesian inference in high-resolution imaging to reveal material properties.
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The mechanical recycling of discarded plastic products as resources for environmental preservation has recently gained research attention. In this context, it is necessary to use waste materials for fiber-reinforced thermoplastics (FRTP). Glass and carbon fibers are often damaged by shear and compression during melt-forming processes. To achieve a sustainable society, it is necessary for thermal recycling to produce minimal to no residue and for mechanical recycling to maintain the length of fibers used in FRTP to preserve their performance as a reinforcing agent. Aramid fibers (AFs) do not shorten during the melt-molding process, and their composites have excellent impact strength. On the other hand, plastics reinforced with glass or carbon fibers are reported to have a superior strength and modulus of elasticity compared to aramid fibers. This study investigates the dispersion of a carbon nanofiber (CNF), a whisker, as the third component in aramid-fiber-reinforced polypropylene (PP/AF). The results and discussion sections demonstrate how the dispersion of CNF in PP/AF can enhance the mechanical properties of injection-molded products without compromising their impact resistance. The proposed composition will have excellent material recyclability and initial mechanical properties compared to glass-fiber-reinforced thermoplastics.
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We investigated artifactual atomic displacements on a Pt (111) surface using annular dark-field (ADF) scanning transmission electron microscopy images under ideal conditions with multi-slice image simulation. Pt atomic columns on the surface exhibited artifact displacement. The bright spots shifted slightly toward the interior of the crystal, indicating that ADF imaging underestimates atomic distance measurements on the crystal surface. Multiple peak fitting is an effective method for determining the positions of bright spots and obtaining more accurate atomic positions while reducing the impact of surface-related artifacts. This is important for the measurement of interatomic distances on crystal surfaces, particularly for catalyst particles.
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Introduction: Acute Leriche syndrome is a rare but potentially life-threatening condition. Pain, pallor, and coldness of the lower extremities serve as clues for suspecting Leriche syndrome. However, the absence of these findings may pose a diagnostic challenge. Case Presentation: An 83-year-old man presented at our emergency department with a complaint of sudden-onset paraparesis. Initially, spinal cord infarction was suspected due to clinical course and neurological findings, but thoracolumbar MRI showed normal findings. On admission, symptoms associated with aortoiliac occlusion were not present, except for muscle atrophy in the thigh. CT angiography revealed aortoiliac occlusion, leading to a diagnosis of Leriche syndrome. Conclusion: Leriche syndrome should be considered as a potential differential diagnosis in patients with acute paraparesis. Muscle atrophy of the lower limbs disproportionate to the clinical course may be the clue for suspecting acute Leriche syndrome with symptoms related to atherosclerotic occlusion which are inconspicuous.
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Two-dimensional freestanding membranes of materials, which can be transferred onto and make interfaces with any material, have attracted attention in the search for functional properties that can be utilized for next-generation nanoscale devices. We fabricated stable 1-nm-thick hafnia membranes exhibiting the metastable rhombohedral structure and out-of-plane ferroelectric polarizations as large as 13 µC/cm2. We also found that the rhombohedral phase transforms into another metastable orthorhombic phase without the ferroelectricity deteriorating as the thickness increases. Our results reveal the key role of the rhombohedral phase in the scale-free ferroelectricity in hafnia and also provide critical insights into the formation mechanism and phase stability of the metastable hafnia. Moreover, ultrathin hafnia membranes enable heterointerfaces and devices to be fabricated from structurally dissimilar materials beyond structural constrictions in conventional film-growth techniques.
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We herein report a case of neurosyphilis that presented with isolated bilateral abducens nerve palsy. A 39-year-old man was referred to our department with diplopia. He had a history of homosexual relationships and showed only bilateral abducens nerve palsy upon a neurological examination. Positive syphilis tests in the serum and cerebrospinal fluid and a contrasting effect on the abducens nerve on magnetic resonance imaging (MRI) confirmed the diagnosis of active neurosyphilis. When a patient manifests isolated abducens nerve palsy, neurosyphilis can be a differential diagnosis, although rare, and contrast-enhanced MRI may help diagnose the disease.
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BACKGROUND: In recent years, intramedullary nails with medial support screws for proximal humeral fractures have become available. Although these devices have a potential risk of iatrogenic axillary nerve injury, no studies have investigated the anatomical relationship between the medial support screws in the modern intramedullary nail and the axillary nerve. This study aimed to clarify the anatomical relationship between the medial support screws in the intramedullary nail and the axillary nerve. MATERIALS AND METHODS: In total, 29 cadaveric shoulders (mean age: 82.6 years old (range: 61-105); 15 males and 14 females) were included in this study. Shoulders within whole-body cadavers were used in all cases. A single proximal humeral nail with medial support screws (ARISTO Proximal Humeral Nail; MDM, Tokyo, Japan) was used. The distance of each medial support screw from the axillary nerve and its branches was measured. RESULTS: In two (6.90%) of 29 shoulders, the axillary nerves came into contact with the medial support screws. In the remaining 27 of 29 shoulders (93.1%), the nerves were located proximal to the medial support screws. CONCLUSION: Medial support screws in proximal humeral fracture nails had the potential to injure the axillary nerve and its branches.
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Histone H2B monoubiquitination (at Lys120 in humans) regulates transcription elongation and DNA repair. In humans, H2B monoubiquitination is catalyzed by the heterodimeric Bre1 complex composed of Bre1A/RNF20 and Bre1B/RNF40. The Bre1 proteins generally function as tumor suppressors, while in certain cancers, they facilitate cancer cell proliferation. To obtain structural insights of H2BK120 ubiquitination and its regulation, we report the cryo-electron microscopy structure of the human Bre1 complex bound to the nucleosome. The two RING domains of Bre1A and Bre1B recognize the acidic patch and the nucleosomal DNA phosphates around SHL 6.0-6.5, which are ideally located to recruit the E2 enzyme and ubiquitin for H2BK120-specific ubiquitination. Mutational experiments suggest that the two RING domains bind in two orientations and that ubiquitination occurs when Bre1A binds to the acidic patch. Our results provide insights into the H2BK120-specific ubiquitination by the Bre1 proteins and suggest that H2B monoubiquitination can be regulated by nuclesomal DNA flexibility.
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Neoplasias , Nucleossomos , Humanos , Microscopia Crioeletrônica , DNA/metabolismo , Histonas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , UbiquitinaçãoRESUMO
The European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) classification criteria for idiopathic inflammatory myopathies (IIM) have been widely used in recent times. However, no studies have focused on electromyography (EMG) findings of IIM, considering the criteria. This study aimed to elucidate the frequency of EMG abnormalities, particularly fibrillation potentials and positive sharp waves (Fib/PSW), the most objective EMG findings of IIM. Clinical and EMG records of adult patients who were clinically diagnosed with polymyositis (PM), dermatomyositis (DM), amyopathic DM (ADM), or inclusion body myositis (IBM) were retrospectively reviewed and classified according to the EULAR/ACR classification criteria. The frequency of Fib/PSW in EMG was investigated in the recruited cases. Seventy-nine patients with clinically diagnosed IIM (44 with PM, 17 with DM, 7 with ADM, and 11 with IBM) were recruited. After classification using EULAR/ACR, 75 satisfied definite or probable IIM (61 and 14, respectively), and the frequency of Fib/PSW in this group was 95%. Furthermore, the remaining 4 patients with insufficient IIM probability also showed Fib/PSW. Fib/PSW may also be seen in cases with insufficient IIM probability not satisfying the criteria. EMG may help detect muscle involvement in these cases through Fib/PSW.
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Doenças do Colágeno , Dermatomiosite , Miosite de Corpos de Inclusão , Miosite , Doenças Reumáticas , Reumatologia , Adulto , Humanos , Estudos Retrospectivos , Miosite/diagnóstico , Dermatomiosite/diagnóstico , Miosite de Corpos de Inclusão/diagnósticoRESUMO
OBJECTIVES: To document the utility of decremental responses in the repetitive nerve stimulation test (RNS) and spontaneous activities in needle electromyography (EMG) in the trapezius muscle for the diagnosis of amyotrophic lateral sclerosis. METHODS: Subjects were retrospectively identified from our EMG database. Cervical spondylosis was represented as a disease control group. We investigated the sensitivity and specificity of RNS and EMG in the trapezius muscle and those of diagnostic criteria including the Gold Coast criteria (GCC). RESULTS: We reviewed 120 patients with amyotrophic lateral sclerosis and 17 patients with cervical spondylosis. "RNS or EMG" achieved the highest sensitivity (85%). The specificity was the highest for RNS (94%). Addition of RNS of the deltoid muscle achieved 98% sensitivity in the upper-limb onset amyotrophic lateral sclerosis. The sensitivity of the GCC was very high (88%). CONCLUSIONS: Neurophysiological parameters investigated in this study having close to 100% specificities or sensitivities are useful as complements to the GCC.
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Esclerose Lateral Amiotrófica , Estimulação Elétrica , Eletromiografia , Sensibilidade e Especificidade , Músculos Superficiais do Dorso , Humanos , Eletromiografia/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Esclerose Lateral Amiotrófica/fisiopatologia , Esclerose Lateral Amiotrófica/diagnóstico , Idoso , Estudos Retrospectivos , Músculos Superficiais do Dorso/fisiopatologia , Adulto , Diagnóstico PrecoceRESUMO
OBJECTIVE: The aim of this study was to clarify the roles of the cerebellum and basal ganglia for temporal integration. METHODS: We studied 39 patients with spinocerebellar degeneration (SCD), comprising spinocerebellar atrophy 6 (SCA6), SCA31, Machado-Joseph disease (MJD, also called SCA3), and multiple system atrophy (MSA). Thirteen normal subjects participated as controls. Participants were instructed to tap on a button in synchrony with isochronous tones. We analyzed the inter-tap interval (ITI), synchronizing tapping error (STE), negative asynchrony, and proportion of delayed tapping as indicators of tapping performance. RESULTS: The ITI coefficient of variation was increased only in MSA patients. The standard variation of STE was larger in SCD patients than in normal subjects, especially for MSA. Negative asynchrony, which is a tendency to tap the button before the tones, was prominent in SCA6 and MSA patients, with possible basal ganglia involvement. SCA31 patients exhibited normal to supranormal performance in terms of the variability of STE, which was surprising. CONCLUSIONS: Cerebellar patients generally showed greater STE variability, except for SCA31. The pace of tapping was affected in patients with possible basal ganglia pathology. SIGNIFICANCE: Our results suggest that interaction between the cerebellum and the basal ganglia is essential for temporal processing. The cerebellum and basal ganglia and their interaction regulate synchronized tapping, resulting in distinct tapping pattern abnormalities among different SCD subtypes.
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Atrofia de Múltiplos Sistemas , Ataxias Espinocerebelares , Degenerações Espinocerebelares , Humanos , Cerebelo , Ataxias Espinocerebelares/patologia , Gânglios da Base/patologiaAssuntos
Doenças do Sistema Nervoso Periférico , Sarcoidose , Nervo Sural , Ultrassonografia , Humanos , Nervo Sural/patologia , Nervo Sural/diagnóstico por imagem , Sarcoidose/diagnóstico por imagem , Sarcoidose/patologia , Ultrassonografia/métodos , Doenças do Sistema Nervoso Periférico/diagnóstico por imagem , Doenças do Sistema Nervoso Periférico/patologia , Biópsia/métodos , Masculino , Pessoa de Meia-Idade , Feminino , AdultoRESUMO
ABSTRACT Objective Perioperative deep prosthetic joint infection (PJI) is a serious postoperative complication of total hip arthroplasty (THA). We aimed to compare the efficacy of cefazolin administered within 24 and 48 h of primary THA for PJI prophylaxis. Methods In this retrospective study, 720 patients were divided into two groups depending on whether cefazolin was administered as a single injection of 2 g twice daily within 24 (24-h group) or 48 h of surgery and the following day (48-h group). Sex, age at surgery, body mass index, co-existing diseases, blood test data, and PJI risk factors were evaluated. Results The 24- and 48-h groups included 364 and 356 patients, respectively. Diabetes mellitus was the most common risk factor for PJI in both groups. The corresponding incidence of perioperative deep PJI following primary THA was 0.55% and 0.28% in the 24- and 48-h groups, respectively. There was no significant difference in patient background characteristics between the groups. Conclusions Cefazolin administration within 24 h of primary THA may be appropriate for perioperative deep PJI. Level of Evidence II; Retrospective study.
RESUMO Objetivo A infecção de prótese articular (IPA) perioperatória profunda é uma grave complicação pós-operatória da artroplastia total de quadril (ATQ). Este estudo buscou comparar a eficácia da cefazolina administrada dentro de 24 e 48 horas após ATQ para profilaxia de IPA. Métodos Neste estudo retrospectivo, 720 pacientes foram divididos em dois grupos, que receberam cefazolina em uma injeção de 2g duas vezes por dia nas primeiras 24 e 48 horas (grupos de 24 e 48 horas), respectivamente. Foram avaliados sexo, idade na data da cirurgia, índice de massa corporal, comorbidades, testes sanguíneos e fatores de risco para IPA. Resultados Os grupos de 24 e 48 horas incluíram, respectivamente, 364 e 356 pacientes. O fator de risco para IPA mais comum nos dois grupos foi o diabetes mellitus. A incidência de IPA perioperatória profunda após ATQ foi, respectivamente, de 0,55% e 0,28% nos grupos de 24 e 48 horas. Não houve diferença significativa nas características gerais dos pacientes entre os dois grupos. Conclusão A administração de cefazolina dentro de 24 horas após ATQ primária pode ser adequada para IPA perioperatória profunda. Nível de Evidência II; Estudo retrospectivo.