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Novel two-dimensional semiconductor crystals can exhibit diverse physical properties beyond their inherent semiconducting attributes, making their pursuit paramount. Memristive properties, as exemplars of these attributes, are predominantly manifested in wide-bandgap materials. However, simultaneously harnessing semiconductor properties alongside memristive characteristics to produce memtransistors is challenging. Herein we prepared a class of semiconducting III-V-derived van der Waals crystals, specifically the HxA1-xBX form, exhibiting memristive characteristics. To identify candidates for the material synthesis, we conducted a systematic high-throughput screening, leading us to 44 prospective III-V candidates; of these, we successfully synthesized ten, including nitrides, phosphides, arsenides and antimonides. These materials exhibited intriguing characteristics such as electrochemical polarization and memristive phenomena while retaining their semiconductive attributes. We demonstrated the gate-tunable synaptic and logic functions within single-gate memtransistors, capitalizing on the synergistic interplay between the semiconducting and memristive properties of our two-dimensional crystals. Our approach guides the discovery of van der Waals materials with unique properties from unconventional crystal symmetries.
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PURPOSE: Adequate oxygenation and airway management during deep sedation can be challenging. We investigated the effect of high-flow nasal cannula (group HF) and conventional nasal cannula (group CO) during sedation for endoscopic submucosal dissection (ESD). METHODS: Patients undergoing ESD with deep sedation were enrolled. The primary outcome was difference in lowest oxygen saturation (SpO2) between the groups. Incidence of hypoxia (SpO2 < 90%), patients with SpO2 < 95%, hypercapnia, and airway interventions; operator satisfaction; and adverse events were recorded. RESULTS: Thirty-two patients in each group completed the study. The mean of minimum SpO2 values was significantly higher in group HF than in group CO (96.8% ± 4.2% vs. 93.3% ± 5.3%, p = 0.005). The incidence of hypoxia was comparable between the groups (4 [12.5%] vs. 6 [18.8%], p = 0.491); however, patients with SpO2 < 95% were significantly less in group HF (5 [15.6%] vs. 18 [56.3%], p = 0.003). Incidence of hypercapnia was higher in group HF than in group CO (14 [46.7%] vs. 5 [16.7%], p = 0.013). Airway rescue interventions were significantly less common in group HF. Satisfaction of operators and post-procedural complications were comparable between the two groups. In multivariable analysis, group CO and higher body mass index were risk factors for airway managements (odds ratio [95% confidence interval]: 6.204 [1.784-21.575], p = 0.004; 1.337 [1.043-1.715], p = 0.022, respectively). CONCLUSIONS: Compared to conventional nasal cannula, high-flow nasal cannula maintained higher minimum SpO2 value during deep sedation with propofol-remifentanil for ESD. TRIAL REGISTRATION: Clinical Trial Registry of the Republic of Korea (KCT0006618, https://cris.nih.go.kr ; registered September 29, 2021; principal investigator: Ji Won Choi).
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The ability to manipulate crystal structures using kinetic control is of broad interest because it enables the design of materials with structures, compositions, and morphologies that may otherwise be unattainable. Herein, we report the low-temperature structural transformation of bulk inorganic crystals driven by hard-soft acid-base (HSAB) chemistry. We show that the three-dimensional framework K2Sb8Q13 and layered KSb5Q8 (Q = S, Se, and Se/S solid solutions) compounds transform to one-dimensional Sb2Q3 nano/microfibers in N2H4·H2O solution by releasing Q2- and K+ ions. At 100 °C and ambient pressure, a transformation process takes place that leads to significant structural changes in the materials, including the formation and breakage of covalent bonds between Sb and Q. Despite the insolubility of the starting crystals in N2H4·H2O under the given conditions, the mechanism of this transformation can be rationalized by applying the HSAB principle. By adjusting factors such as the reactants' acid/base properties, temperature, and pressure, the process can be controlled, allowing for the achievement of a wide range of optical band gaps (ranging from 1.14 to 1.59 eV) while maintaining the solid solution nature of the anion sublattice in the Sb2Q3 nanofibers.
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p21WAF1/Cip1 acts as a key negative regulator of cell cycle progression, which can form complexes with cyclin-dependent kinases together with specific cyclins to induce cell cycle arrest at specific stages. p21 protein levels have been shown to be regulated primarily through phosphorylation and ubiquitination during various stages of the cell cycle. Although phosphorylation and ubiquitin-dependent proteasomal degradation of p21 have been well established, other post-translational modifications that contribute to regulation of p21 stability and function remain to be further elucidated. Here, we show that p21 degradation and its function are controlled by tankyrases, which are members of the poly(ADP-ribose) polymerase (PARP) protein family. p21 interacts with tankyrases via newly defined tankyrase-binding motifs and is PARylated by tankyrases in vitro and in vivo, suggesting that PARylation is a new post-translational modification of p21. Up-regulation of tankyrases induces ubiquitin-dependent proteasomal degradation of p21 through an E3 ligase RNF146, thus promoting cell cycle progression in the G1/S phase transition. On the contrary, inhibition of tankyrases by knockdown or inhibitor treatment stabilizes p21 protein and leads to cell cycle arrest in the G1 phase. Together, our data demonstrate that tankyrase may function as a new molecular regulator that controls the protein levels of p21 through PARylation-dependent proteasomal degradation. Hence, a novel function of the tankyrase-p21 axis may represent a new avenue for regulating cell cycle progression.
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Tanquirases , Tanquirases/química , Tanquirases/metabolismo , Poli ADP Ribosilação , Ubiquitinação , Ciclo Celular , Ubiquitinas/metabolismoRESUMO
The core task for Mott insulators includes how rigid distributions of electrons evolve and how these induce exotic physical phenomena. However, it is highly challenging to chemically dope Mott insulators to tune properties. Herein, we report how to tailor electronic structures of the honeycomb Mott insulator RuCl3 employing a facile and reversible single-crystal to single-crystal intercalation process. The resulting product (NH4 )0.5 RuCl3 â 1.5 H2 O forms a new hybrid superlattice of alternating RuCl3 monolayers with NH4 + and H2 O molecules. Its manipulated electronic structure markedly shrinks the Mott-Hubbard gap from 1.2 to 0.7â eV. Its electrical conductivity increases by more than 103 folds. This arises from concurrently enhanced carrier concentration and mobility in contrary to the general physics rule of their inverse proportionality. We show topotactic and topochemical intercalation chemistry to control Mott insulators, escalating the prospect of discovering exotic physical phenomena.
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Doping and alloying are fundamental strategies to improve the thermoelectric performance of bare materials. However, identifying outstanding elements and compositions for the development of high-performance thermoelectric materials is challenging. In this study, we present a data-driven approach to improve the thermoelectric performance of SnSe compounds with various doping. Based on the newly generated experimental and computational dataset, we built highly accurate predictive models of thermoelectric properties of doped SnSe compounds. A well-designed feature vector consisting of the chemical properties of a single atom and the electronic structures of a solid plays a key role in achieving accurate predictions for unknown doping elements. Using the machine learning predictive models and calculated map of the solubility limit for each dopant, we rapidly screened high-dimensional material spaces of doped SnSe and evaluated their thermoelectric properties. This data-driven search provided overall strategies to optimize and improve the thermoelectric properties of doped SnSe compounds. In particular, we identified five dopant candidate elements (Ge, Pb, Y, Cd, and As) that provided a high ZT exceeding 2.0 and proposed a design principle for improving the ZT by Sn vacancies depending on the doping elements. Based on the search, we proposed yttrium as a new high-ZT dopant for SnSe with experimental confirmations. Our research is expected to lead to novel high-ZT thermoelectric material candidates and provide cutting-edge research strategies for materials design and extraction of design principles through data-driven research.
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Thermoelectric materials generate electric energy from waste heat, with conversion efficiency governed by the dimensionless figure of merit, ZT. Single-crystal tin selenide (SnSe) was discovered to exhibit a high ZT of roughly 2.2-2.6 at 913 K, but more practical and deployable polycrystal versions of the same compound suffer from much poorer overall ZT, thereby thwarting prospects for cost-effective lead-free thermoelectrics. The poor polycrystal bulk performance is attributed to traces of tin oxides covering the surface of SnSe powders, which increases thermal conductivity, reduces electrical conductivity and thereby reduces ZT. Here, we report that hole-doped SnSe polycrystalline samples with reagents carefully purified and tin oxides removed exhibit an ZT of roughly 3.1 at 783 K. Its lattice thermal conductivity is ultralow at roughly 0.07 W m-1 K-1 at 783 K, lower than the single crystals. The path to ultrahigh thermoelectric performance in polycrystalline samples is the proper removal of the deleterious thermally conductive oxides from the surface of SnSe grains. These results could open an era of high-performance practical thermoelectrics from this high-performance material.
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Sewage surveillance is increasingly employed as a supplementary tool for COVID-19 control. Experiences learnt from large-scale trials could guide better interpretation of the sewage data for public health interventions. Here, we compared the performance of seven commonly used primer-probe sets in RT-qPCR and evaluated the usefulness in the sewage surveillance program in Hong Kong. All selected primer-probe sets reliably detected SARS-CoV-2 in pure water at 7 copies per µL. Sewage matrix did not influence RT-qPCR determination of SARS-CoV-2 concentrated from a small-volume sewage (30 mL) but introduced inhibitory impacts on a large-volume sewage (920 mL) with a ΔCt of 0.2-10.8. Diagnostic performance evaluation in finding COVID-19 cases showed that N1 was the best single primer-probe set, while the ORF1ab set is not recommended. Sewage surveillance using the N1 set for over 3200 samples effectively caught the outbreak trend and, importantly, had a 56% sensitivity and a 96% specificity in uncovering the signal sources from new cases and/or convalescent patients in the community. Our study paves the way for selecting detection primer-probe sets in wider applications in responding to the COVID-19 pandemic.
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COVID-19 , COVID-19/epidemiologia , Humanos , Pandemias , Saúde Pública , RNA Viral/análise , SARS-CoV-2/genética , Sensibilidade e Especificidade , EsgotosRESUMO
BACKGROUND: Prognostic cytological and molecular features of uveal melanoma have been well researched and are essential in management. Samples can be obtained in vivo through fine needle aspirate biopsy, vitrector cutter, forceps or post-enucleation for off-site testing. This study aims to examine cytological and chromosome microarray yields of these samples. METHODS: A retrospective cohort analysis of 119 uveal melanoma biopsies submitted to our laboratory. Samples included those taken in vivo (n = 57) and post-enucleation (n = 62). Patient and tumour features were collected including age, sex, primary tumour location, basal diameter and tumour height. Prognostic outcomes measured include cell morphology, chromosomal status and immunohistochemistry. RESULTS: Post-enucleation biopsies accounted for just over half of our samples (52%). Post-enucleation samples had a more successful genetic yield than in vivo biopsies (77% vs. 50%, p = 0.04) though there was no difference for cytological yields. There was no difference in cytological or microarray yields between instruments. The vitrector biopsy group had the smallest tumour thickness (5 mm vs. 10 mm [fine-needle aspirate biopsy], p = 0.003). There was a strong correlation between monosomy 3, BAP1 aberrancy and epithelioid cell type in post-enucleation samples (Tb = 0.742, p = 0.005). However, epithelioid morphology was not associated with either monosomy 3 (p = 0.07) or BAP1 aberrancy (p = 0.24) for in vivo biopsies. CONCLUSIONS: All three biopsy instruments provide similar cytological yields as post-enucleation sampling, although post-enucleation samples had a more successful chromosome microarray yield. Epithelioid cytomorphology alone is insufficient for prognostication in in vivo biopsies, immunohistochemistry would be a useful surrogate test.
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Neoplasias Uveais , Biópsia por Agulha Fina , Humanos , Melanoma , Monossomia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Neoplasias Uveais/diagnóstico , Neoplasias Uveais/genética , Neoplasias Uveais/metabolismoRESUMO
BACKGROUND: Coronavirus disease 2019 (COVID-19) is generally asymptomatic or mild in otherwise healthy children, however, severe cases may occur. In this study, we report the clinical characteristics of children classified as critical COVID-19 in Korea to provide further insights into risk factors and management in children. METHODS: This study was a retrospective case series of children < 18 years of age classified as critical COVID-19. Cases were identified by the Korea Disease Control and Prevention Agency surveillance system and medical records were reviewed. Critical COVID-19 was defined as cases with severe illness requiring noninvasive (high flow nasal cannula, continuous positive airway pressure, or bilevel positive airway pressure) or invasive mechanical ventilation, extracorporeal membrane oxygenation (ECMO) or continuous renal replacement therapy (CRRT), between January 20, 2020 and October 7, 2021. RESULTS: Among 39,146 cases diagnosed with COVID-19 in subjects < 18 years of age, eight cases (0.02%) were identified as critical COVID-19. The median age was 13 years (range 10 month-17 years) and male-to-female ratio was 1:1. Three children had underlying diseases; one child has asthma and major depressive disorder, one child had Lennox-Gastaut syndrome and one child had mental retardation and was newly diagnosed with type 2 diabetes mellitus with the diagnosis of COVID-19. Among the eight children, seven were obese (body mass index range [BMI] median 29.3, range 25.9-38.2, weight-for-length > 97% for infant) and one was overweight (BMI 21.3). All patients had fever, six patients had dyspnea or cough and other accompanied symptoms included sore throat, headache, lethargy and myalgia. Radiologic findings showed pneumonia within 1-8 days after symptom onset. Pneumonia progressed in these children for 2-6 days and was improved within 5-32 days after diagnosis. Among the eight critical cases, remdesivir was administered in six cases. Steroids were provided for all cases. Inotropics were administered in one case. Six cases were treated with noninvasive mechanical ventilator and three required mechanical ventilator. One case required ECMO due to acute respiratory distress syndrome. All cases were admitted to the intensive care unit and admission period ranged from 9-39 days. Among all critical COVID-19 cases < 18 years of age, there were no fatal cases. CONCLUSION: To develop appropriate policies for children in the COVID-19 pandemic, it is important to monitor and assess the clinical burden in this population.
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COVID-19/epidemiologia , SARS-CoV-2 , Adolescente , COVID-19/complicações , COVID-19/terapia , Criança , Pré-Escolar , Cuidados Críticos , Feminino , Humanos , Lactente , Masculino , República da Coreia/epidemiologia , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
Extraordinary properties of traditional hyperbolic metamaterials, not found in nature, arise from their man-made subwavelength structures causing unique light-matter interactions. However, their preparation requiring nanofabrication processes is highly challenging and merely provides nanoscale two-dimensional structures. Stabilizing their bulk forms via scalable procedures has been a sought-goal for broad applications of this technology. Herein, we report a new strategy of designing and realizing bulk metamaterials with finely tunable hyperbolic responses. We develop a facile two-step process: (1) self-assembly to obtain heterostructured nanohybrids of building blocks and (2) consolidation to convert nanohybrid powders to dense bulk pellets. Our samples have centimeter-scale dimensions typically, readily further scalable. Importantly, the thickness of building blocks and their relative concentration in bulk materials serve as a delicate means of controlling hyperbolic responses. The resulting new bulk heterostructured material system consists of the alternating h-BN and graphite/graphene nanolayers and exhibits significant modulation in both type-I and type-II hyperbolic resonance modes. It is the first example of real bulk hyperbolic metamaterials, consequently displaying the capability of tuning their responses along both in-plane and out-of-plane directions of the materials for the first time. It also distinctly interacts with unpolarized and polarized transverse magnetic and electronic beams to give unique hyperbolic responses. Our achievement can be a new platform to create various bulk metamaterials without complicated nanofabrication techniques. Our facile synthesis method using common laboratory techniques can open doors to broad-range researchers for active interdisciplinary studies for this otherwise hardly accessible technology.
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BACKGROUND: Anti-acetylcholine receptor antibody (AChR-Abs) testing is a safe and simple ancillary method for confirming the diagnosis of myasthenia gravis. Despite the test's high sensitivity (85%-90%) for generalized myasthenia gravis, AChR-Abs testing has been reported to have a low sensitivity 44%-66% for ocular myasthenia gravis (OMG). The aim of the study is to assess the effectiveness of AChR binding Abs testing for diagnosing OMG by evaluating the test's sensitivity, specificity, positive predictive value, and negative predictive value. METHODS: A retrospective chart review on 114 OMG suspects who presented to the emergency department of a tertiary eye center in Victoria, Australia, was completed. The patients presented with diplopia alone, ptosis alone, or the combination of diplopia and ptosis. All participants were followed up longitudinally in the neuro-ophthalmology outpatient clinics for the average of 2.8 months, where they have received AChR binding testing. The final diagnosis was only given to the patients who either were seropositive for AChR binding Abs and had a high clinical suspicion of OMG, or the patient who was seronegative for AChR binding Abs but was regarded as likely to have OMG clinically and responded to the diagnostic treatments (pyridostigmine bromide and immunosuppressant therapy). RESULTS: The sensitivity of AChR binding Abs testing in diagnosing OMG was higher (80%; 95% confidence interval [CI], 51.91%-95.67%) than previously reported (44%-66%). AChR binding Abs testing also had a high specificity (98.99%; 95% CI, 94.50%-99.97%) and positive predictive value (92.31%; 95% CI, 62.68%-98.85%). CONCLUSION: The study suggests the higher utility of the AChR binding Abs testing in diagnosing OMG due to its high sensitivity, specificity, and positive predictive value.
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Blefaroptose , Miastenia Gravis , Autoanticorpos , Blefaroptose/diagnóstico , Humanos , Miastenia Gravis/tratamento farmacológico , Receptores Colinérgicos , Estudos RetrospectivosRESUMO
BACKGROUND/OBJECTIVE: Melasma is a commonly acquired disorder of hyperpigmentation that often poses a therapeutic challenge for dermatologists. Recently, cysteamine cream has shown promising results compared to placebo. This study aims to determine the efficacy of cysteamine cream compared to hydroquinone cream in the treatment of melasma. METHODS: A randomised, double-blinded, single-centre trial was conducted in Victoria, Australia. 20 recruited participants were given either cysteamine cream or hydroquinone cream for 16 weeks. The primary outcome measure was a change in the modified Melasma Area and Severity Index (mMASI). Quality of life at baseline and week 16 as well as standard digital photography at each follow-up visit was assessed as secondary outcome measures. RESULTS: At week 16, 14 participants completed the study with 5 participants in the cysteamine group and 9 patients in the hydroquinone group. In the intention to treat analysis, there was a 1.52 ± 0.69 (21.3%) reduction in mMASI for the cysteamine group and a 2.96 ± 1.15 (32%) reduction in the hydroquinone group. The difference between groups was not statistically significant (P = 0.3). Hydroquinone cream was generally better tolerated that cysteamine cream. CONCLUSION: Our study suggests that topical cysteamine may have comparable efficacy to topical hydroquinone. Cysteamine thus provides a possible alternative to patients and clinicians who wish to avoid or rotate off topical hydroquinone. While side effects were more common for participants using cysteamine compared with hydroquinone, these were mild and reversible. Larger studies comparing cysteamine and hydroquinone are required to support these findings.
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Cisteamina/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Hidroquinonas/uso terapêutico , Melanose/tratamento farmacológico , Administração Tópica , Adulto , Método Duplo-Cego , Feminino , Humanos , Pomadas , Qualidade de VidaRESUMO
BACKGROUND: The major determining factor of prognosis of oral squamous cell carcinoma is cervical lymph node metastasis. 6,8-Diprenylgenistein (6,8-DG), an isoflavonoid isolated from Cudrania tricuspidata has been reported to have anti-microbial and anti-obesity activities. However, its effects on lymphangiogenesis and lymph node metastasis in oral cancer have not yet been reported. METHODS: To investigate the in vitro inhibitory effects of 6,8-DG on VEGF-A-induced lymphangiogenesis, we performed the proliferation, tube formation, and migration assay using human lymphatic microvascular endothelial cells (HLMECs). RT-PCR, Western blot, immunoprecipitation, ELISA and co-immunoprecipitation assays were used to investigate the expression levels of proteins, and mechanism of 6,8-DG. The in vivo inhibitory effects of 6,8-DG were investigated using an oral cancer sentinel lymph node (OCSLN) animal model. RESULTS: 6,8-DG inhibited the proliferation, migration and tube formation of rhVEGF-A treated HLMECs. In addition, the in vivo lymphatic vessel formation stimulated by rhVEGF-A was significantly reduced by 6,8-DG. 6,8-DG inhibited the expression of VEGF-A rather than other lymphangiogenic factors in CoCl2-treated SCCVII cells. 6,8-DG inhibited the expression and activation of VEGFR-2 stimulated by rhVEGF-A in HLMECs. Also, 6,8-DG inhibited the activation of the lymphangiogenesis-related downstream signaling factors such as FAK, PI3K, AKT, p38, and ERK in rhVEGF-A-treated HLMECs. Additionally, 6,8-DG inhibited the expression of the hypoxia-inducible factor (HIF-1α), which is involved in the expression of VEGF-A in CoCl2-treated SCCVII cells, and 6,8-DG inhibited VEGF-A signaling via interruption of the binding of VEGF-A and VEGFR-2 in HLMECs. In the VEGF-A-induced OCSLN animal model, we confirmed that 6,8-DG suppressed tumor-induced lymphangiogenesis and SLN metastasis. CONCLUSION: These data suggest that 6,8-DG inhibits VEGF-A-induced lymphangiogenesis and lymph node metastasis in vitro and in vivo. Furthermore, the inhibitory effects of 6,8-DG are probably mediated by inhibition of VEGF-A expression in cancer cells and suppression of the VEGF-A/VEGFR-2 signaling pathway in HLMEC. Thus, 6,8-DG could be novel and valuable therapeutic agents for metastasis prevention and treatment of oral cancer.
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Anticarcinógenos/uso terapêutico , Genisteína/análogos & derivados , Linfangiogênese/efeitos dos fármacos , Metástase Linfática/tratamento farmacológico , Neoplasias Bucais/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Anticarcinógenos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Feminino , Genisteína/farmacologia , Genisteína/uso terapêutico , Humanos , Metástase Linfática/patologia , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/metabolismo , Linfonodo Sentinela/efeitos dos fármacos , Linfonodo Sentinela/metabolismo , Linfonodo Sentinela/patologiaRESUMO
Basal cell carcinoma (BCC) is the most common type of malignant tumor in the periocular region. BCCs with neuroendocrine differentiation in the periocular region, however, have not been described in the literature.We present a retrospective case review of a patient with an eyelid BCC with neuroendocrine differentiation. Demographical, clinical, radiological, surgical, histological, and follow-up data are presented.The patient presented with a slow-growing lesion of the eyelid with associated epiphora and dull ache. Initial incisional biopsy of the lesion revealed an infiltrating carcinoma composed of epithelial cells. Immunohistochemistry showed that the tumor was positive for p40, Ber-Ep4, neuron specific enolase (NSE), chromogranin A, CD56 (NCAM), and synaptophysin. The pathology from the margin-controlled excision showed basosquamous cell carcinoma with neuroendocrine differentiation. Tumor recurrence was not detected clinically at the post-operative six-month review.BCC with neuroendocrine marker positivity represents an important diagnostic differential for rare eyelid carcinomas such as primary cutaneous neuroendocrine carcinoma and metastatic small cell carcinoma that have a poor prognosis. The prognostic importance of neuroendocrine marker positivity in BCCs is uncertain. The present case provides further evidence for neuroendocrine differentiation in BCCs.
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Carcinoma Basocelular , Neoplasias Palpebrais , Carcinoma Basocelular/diagnóstico , Carcinoma Basocelular/cirurgia , Diferenciação Celular , Neoplasias Palpebrais/diagnóstico , Neoplasias Palpebrais/cirurgia , Pálpebras , Humanos , Recidiva Local de Neoplasia , Estudos RetrospectivosRESUMO
Thermoelectric materials with high average power factor and thermoelectric figure of merit (ZT) has been a sought-after goal. Here, we report new n-type thermoelectric system CuxPbSe0.99Te0.01 (x = 0.0025, 0.004, and 0.005) exhibiting record-high average ZT â¼ 1.3 over 400-773 K ever reported for n-type polycrystalline materials including the state-of-the-art PbTe. We concurrently alloy Te to the PbSe lattice and introduce excess Cu to its interstitial voids. Their resulting strong attraction facilitates charge transfer from Cu atoms to the crystal matrix significantly. It follows the increased carrier concentration without damaging its mobility and the consequently improved electrical conductivity. This interaction also increases effective mass of electron in the conduction band according to DFT calculations, thereby raising the magnitude of Seebeck coefficient without diminishing electrical conductivity. Resultantly, Cu0.005PbSe0.99Te0.01 attains an exceptionally high average power factor of â¼27 µW cm-1 K-2 from 400 to 773 K with a maximum of â¼30 µW cm-1 K-2 at 300 K, the highest among all n- and p-type PbSe-based materials. Its â¼23 µW cm-1 K-2 at 773 K is even higher than â¼21 µW cm-1 K-2 of the state-of-the-art n-type PbTe. Interstitial Cu atoms induce the formation of coherent nanostructures. They are highly mobile, displacing Pb atoms from the ideal octahedral center and severely distorting the local microstructure. This significantly depresses lattice thermal conductivity to â¼0.2 Wm-1 K-1 at 773 K below the theoretical lower bound. The multiple effects of the dual incorporation of Cu and Te synergistically boosts a ZT of Cu0.005PbSe0.99Te0.01 to â¼1.7 at 773 K.
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OBJECTIVE: To develop a method for noninvasive prenatal paternity testing based on targeted sequencing of single nucleotide polymorphisms (SNPs). METHOD: SNPs were selected based on population genetics data. Target-SNPs in cell-free DNA extracted from maternal blood (maternal cfDNA) were analyzed by targeted sequencing wherein target enrichment was based on multiplex amplification using QIAseq Targeted DNA Panels with Unique Molecular Identifiers. Fetal SNP genotypes were called using a novel bioinformatics algorithm, and the combined paternity indices (CPIs) and resultant paternity probabilities were calculated. RESULTS: Fetal SNP genotypes obtained from targeted sequencing of maternal cfDNA were 100% concordant with those from amniotic fluid-derived fetal genomic DNA. From an initial panel of 356 target-SNPs, an average of 148 were included in paternity calculations in 15 family trio cases, generating paternity probabilities of greater than 99.9999%. All paternity results were confirmed by short-tandem-repeat analysis. The high specificity of the methodology was validated by successful paternity discrimination between biological fathers and their siblings and by large separations between the CPIs calculated for the biological fathers and those for 60 unrelated men. CONCLUSION: The novel method is highly effective, with substantial improvements over similar approaches in terms of reduced number of target-SNPs, increased accuracy, and reduced costs.
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Ácidos Nucleicos Livres/análise , Teste Pré-Natal não Invasivo/métodos , Paternidade , Algoritmos , Biologia Computacional , Feminino , Humanos , Masculino , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , GravidezRESUMO
PURPOSE: To investigate the changes in higher-order aberrations (HOAs) after silicone oil removal and to evaluate their associations with visual acuity. METHODS: Fifty-nine eyes of 58 patients who underwent SO removal were included. Total, corneal, and internal optic HOAs, and best-corrected visual acuity were measured before and 1 month after SO removal, and changes were compared between phakic and pseudophakic eyes. RESULTS: Total ocular and internal optic HOAs decreased significantly after SO removal both in pseudophakic (n = 40, all P < 0.001) and phakic eyes (n = 19, P = 0.017, P = 0.004). Preoperative HOAs (P < 0.001) and changes in HOAs (P = 0.006) were greater in pseudophakic eyes than in phakic eyes. Best-corrected visual acuity was significantly improved after SO removal, from 20/105 to 20/78 (P < 0.001) in pseudophakic eyes, whereas there was no difference in phakic eyes (P = 0.714). Preoperative HOAs and the reduction in HOAs after SO removal were greater in best-corrected visual acuity-improved eyes than best-corrected visual acuity-unchanged eyes (P < 0.001). CONCLUSION: Silicone oil tamponade induced an increase in HOAs, and these increases were greater in pseudophakic eyes than in phakic eyes. Silicone oil may cause additional visual impairments because of HOAs, beyond those caused by retinal diseases, particularly in pseudophakic eyes.
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Aberrações de Frente de Onda da Córnea/fisiopatologia , Tamponamento Interno/métodos , Refração Ocular/fisiologia , Doenças Retinianas/cirurgia , Óleos de Silicone/administração & dosagem , Acuidade Visual , Cirurgia Vitreorretiniana/métodos , Adolescente , Adulto , Idoso , Aberrações de Frente de Onda da Córnea/diagnóstico , Aberrações de Frente de Onda da Córnea/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
Cellular senescence can be induced by high levels of reactive oxygen species (ROS) produced by mitochondria. However, the mechanism by which elevated mitochondrial ROS levels are produced during replicative senescence is not yet fully understood. Here, we report that loss of the RNA-binding protein, human antigen R (HuR), during replicative senescence leads to an increase in ROS levels through enhanced mitochondrial localization of the telomeric protein TIN2. HuR binds to the 3' untranslated region of TIN2 mRNA. This association decreases TIN2 protein levels by both destabilizing TIN2 mRNA and reducing its translation. Conversely, depletion of HuR levels enhances TIN2 expression, leading to increased mitochondrial targeting of TIN2. Mitochondrial localization of TIN2 increases ROS levels, which contributes to induction and maintenance of cellular senescence. Our findings provide compelling evidence for a novel role of HuR in controlling the process of cellular senescence by regulating TIN2-mediated mitochondrial ROS production, and for a useful therapeutic route for modulating intracellular ROS levels in treating both aging-related complications and cancer.
Assuntos
Senescência Celular/genética , Proteína Semelhante a ELAV 1/metabolismo , Proteínas de Ligação a Telômeros/genética , Regiões 3' não Traduzidas , Linhagem Celular , Núcleo Celular/metabolismo , Proteína Semelhante a ELAV 1/antagonistas & inibidores , Humanos , Mitocôndrias/metabolismo , Biossíntese de Proteínas , Estabilidade de RNA , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Ligação a Telômeros/metabolismoRESUMO
INTRODUCTION: The purpose of this study was to report the one-year results of treatment of diabetic macular edema (DME) with aflibercept using a treat-and-extend regimen (TER). METHODS: This was a prospective, multicenter, single-arm study planned for 2 years. The eyes received 5 consecutive intravitreal injections of 2 mg of aflibercept every 4 weeks, and the interval between injections was then adjusted by 2 weeks based on changes in the central subfield macular thickness (CSMT). If the CSMT was worse, stable, or better, the interval was shortened, extended, or maintained, respectively. The primary outcome measure was the change in best-corrected visual acuity (BCVA) from baseline to 104 weeks, and the secondary outcome was the change in BCVA from baseline to 52 weeks. RESULTS: Of the 48 patients enrolled, 46 completed a 1-year visit. BCVA improved significantly by 9.1 letters (95% confidence interval: 5.3-13.0 letters) from 56.2 letters at baseline (p < 0.001), and CSMT decreased by -171.7 µm from 489.4 to 317.7 µm (p < 0.001). The proportion of eyes having 20/40 or better vision increased from 17.4 to 41.3%, and the proportion of eyes that gained ≥15 letters was 28.3%. The mean number of injections was 8.5 times for 52 weeks. Worsening of macular edema did not occur in 76.1% of eyes during the extension period, and the interval between injections was extended to 12 weeks in 73.9% of eyes at 52 weeks. CONCLUSIONS: The TER showed 1-year efficacy comparable to that of the fixed dosing regimen of pivotal trials, and its flexible dosing would prevent overtreatment.