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1.
Angew Chem Int Ed Engl ; : e202406889, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742478

RESUMO

Given the merits of abundant resource, low cost and high electrochemical activity, hard carbons have been regarded as one of the most commercializable anode material for sodium-ion batteries (SIBs). However, poor rate capability is one of the main obstacles that severely hinder its further development. In addition, the relationships between preparation method, material structure and electrochemical performance have not been clearly elaborated. Herein, a simple but effective strategy is proposed to accurately construct the multiple structural features in hard carbon via adjusting the components of precursors. Through detailed physical characterization of the hard carbons derived from different regulation steps, and further combined with in-situ Raman and galvanostatic intermittent titration technique (GITT) analysis, the network of multiple relationships between preparation method, microstructure, sodium storage behavior and electrochemical performance have been successfully established. Simultaneously, exceptional rate capability about 108.8 mAh g-1 at 8 A g-1 have been achieved from RHC sample with high reversible capacity and desirable initial Coulombic efficiency (ICE). Additionally, the practical applications can be extended to cylindrical battery with excellent cycle behaviors. Such facile approach can provide guidance for large-scale production of high-performance hard carbons and provides the possibility of building practical SIBs with high energy density and durability.

2.
Psychol Med ; 53(15): 7189-7202, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36994747

RESUMO

BACKGROUND: Abnormal reward functioning is central to anhedonia and amotivation symptoms of schizophrenia (SCZ). Reward processing encompasses a series of psychological components. This systematic review and meta-analysis examined the brain dysfunction related to reward processing of individuals with SCZ spectrum disorders and risks, covering multiple reward components. METHODS: After a systematic literature search, 37 neuroimaging studies were identified and divided into four groups based on their target psychology components (i.e. reward anticipation, reward consumption, reward learning, effort computation). Whole-brain Seed-based d Mapping (SDM) meta-analyses were conducted for all included studies and each component. RESULTS: The meta-analysis for all reward-related studies revealed reduced functional activation across the SCZ spectrum in the striatum, orbital frontal cortex, cingulate cortex, and cerebellar areas. Meanwhile, distinct abnormal patterns were found for reward anticipation (decreased activation of the cingulate cortex and striatum), reward consumption (decreased activation of cerebellum IV/V areas, insula and inferior frontal gyri), and reward learning processing (decreased activation of the striatum, thalamus, cerebellar Crus I, cingulate cortex, orbitofrontal cortex, and parietal and occipital areas). Lastly, our qualitative review suggested that decreased activation of the ventral striatum and anterior cingulate cortex was also involved in effort computation. CONCLUSIONS: These results provide deep insights on the component-based neuro-psychopathological mechanisms for anhedonia and amotivation symptoms of the SCZ spectrum.


Assuntos
Esquizofrenia , Estriado Ventral , Humanos , Esquizofrenia/diagnóstico por imagem , Anedonia , Motivação , Imageamento por Ressonância Magnética/métodos , Recompensa , Encéfalo/diagnóstico por imagem , Neuroimagem , Mapeamento Encefálico , Estriado Ventral/diagnóstico por imagem
3.
Gastrointest Endosc ; 97(2): 335-346, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35985375

RESUMO

BACKGROUND AND AIMS: Endoscopy is increasingly performed for evaluating patients with ulcerative colitis (UC). However, its diagnostic accuracy is largely affected by the subjectivity of endoscopists' experience and scoring methods, and scoring of selected endoscopic images cannot reflect the inflammation of the entire intestine. We aimed to develop an automatic scoring system using deep-learning technology for consistent and objective scoring of endoscopic images and full-length endoscopic videos of patients with UC. METHODS: We collected 5875 endoscopic images and 20 full-length videos from 332 patients with UC who underwent colonoscopy between January 2017 and March 2021. We trained the artificial intelligence (AI) scoring system using these images, which was then used for full-length video scoring. To more accurately assess and visualize the full-length intestinal inflammation, we divided the large intestine into a fixed number of "areas" (cecum, 20; transverse colon, 20; descending colon, 20; sigmoid colon, 15; rectum, 10). The scoring system automatically scored inflammatory severity of 85 areas from every video and generated a visualized result of full-length intestinal inflammatory activity. RESULTS: Compared with endoscopist scoring, the trained convolutional neural network achieved 86.54% accuracy in the Mayo-scored task, whereas the kappa coefficient was .813 (95% confidence interval [CI], .782-.844). The metrics of the Ulcerative Colitis Endoscopic Index of Severity-scored task were encouraging, with accuracies of 90.7%, 84.6%, and 77.7% and kappa coefficients of .822 (95% CI, .788-.855), .784 (95% CI, .744-.823), and .702 (95% CI, .612-.793) for vascular pattern, erosions and ulcers, and bleeding, respectively. The AI scoring system predicted each bowel segment's score and displayed distribution of inflammatory activity in the entire large intestine using a 2-dimensional colorized image. CONCLUSIONS: We established a novel deep learning-based scoring system to evaluate endoscopic images from patients with UC, which can also accurately describe the severity and distribution of inflammatory activity through full-length intestinal endoscopic videos.


Assuntos
Colite Ulcerativa , Aprendizado Profundo , Humanos , Colite Ulcerativa/diagnóstico por imagem , Inteligência Artificial , Colonoscopia , Inflamação , Computadores , Índice de Gravidade de Doença , Mucosa Intestinal
4.
Inorg Chem ; 62(27): 10665-10674, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37365822

RESUMO

Synthesis of chiral molecules for understanding and revealing the expression, transfer, and amplification of chirality is beneficial to explore effective chiral medicines and high-performance chiroptical materials. Herein, we report a series of square-planar phosphorescent platinum(II) complexes adopting a dominantly closed conformation that exhibit efficient chiroptical transfer and enhancement due to the nonclassical intramolecular C-H···O or C-H···F hydrogen bonds between bipyridyl chelating and alkynyl auxiliary ligands as well as the intermolecular π-π stacking and metal-metal interactions. The spectroscopic and theoretical calculation results demonstrate that the chirality and optic properties are regulated from the molecular level to hierarchical assemblies. Notably, a 154 times larger gabs value of the circular dichroism signals is obtained. This study provides a feasible design principle to achieve large chiropticity and control the expression and transfer of the chirality.

5.
J Appl Clin Med Phys ; 24(11): e14116, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37538022

RESUMO

Personalized precision irradiation of patients with left-sided breast cancer is possible by examining the setup errors of 3- and 4-mm gated window widths for those treated with deep inspiration breath-hold (DIBH) treatment. An observational study was performed via a retrospective analysis of 250 cone-beam computed tomography (CBCT) images of 60 left-breast cancer patients who underwent whole-breast radiotherapy with the DIBH technique between January 2021 and 2022 at our hospital. Among them, 30 patients had a gated window width of 3 mm, while the remaining 30 had a gated window width of 4 mm; both groups received radiotherapy using DIBH technology. All patients underwent CBCT scans once a week, and the setup errors in the left-right (x-axis), inferior-superior (y-axis), and anterior-posterior (z-axis) directions were recorded. The clinical-to-planning target volume (CTV-PTV) margins of the two gating windows were calculated using established methods. The setup error in the Y direction was 1.69 ± 1.33 mm for the 3-mm - wide gated window and 2.42 ± 3.02 mm for the 4-mm - wide gated window. The two groups had statistically significant differences in the overall mean setup error (Dif 0.7, 95% CI 0.15-1.31, t = 2.48, p= 0.014). The Z-direction setup error was 2.32 ± 2.12 mm for the 3-mm - wide gated window and 3.15 ± 3.34 mm for the 4-mm - wide gated window. The overall mean setup error was statistically significant between the two groups (Dif 0.8, 95% CI 0.13-1.53, t= 2.34, p = 0.020). There was no significant difference in the X-direction setup error (p > 0.05). Therefore, the CTV-PTV margin values for a 3-mm gated window width in the X, Y, and Z directions are 5.51, 5.15, and 7.28 mm, respectively; those for a 4-mm gated window width in the X, Y, and Z directions are 5.52, 8.16, and 10.21 mm, respectively. The setup errors of the 3-mm - wide gating window are smaller than those of the 4-mm - wide gating window in the three dimensions. Therefore, when the patient's respiratory gating window width is reduced, the margin values of CTV-PTV can be reduced to increase the distance between the PTV and the organs at risk (OARs), which ensures adequate space for the dose to decrease, resulting in lower dose exposure to the OARs (heart, lungs, etc.), thus sparing the OARs from further damage. However, some patients with poor pulmonary function or unstable breathing amplitudes must be treated with a slightly larger gating window. Therefore, this study lays a theoretical basis for personalized precision radiotherapy, which can save time and reduce manpower in the delivery of clinical treatment to a certain extent. Another potential benefit of this work is to bring awareness to the potential implications of a slightly larger gating window during treatment without considering the resulting dosimetric impact.


Assuntos
Neoplasias da Mama , Neoplasias Unilaterais da Mama , Humanos , Feminino , Suspensão da Respiração , Estudos Retrospectivos , Neoplasias da Mama/radioterapia , Tomografia Computadorizada por Raios X/métodos , Respiração , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Neoplasias Unilaterais da Mama/radioterapia
6.
Int J Mol Sci ; 22(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34445536

RESUMO

Chronic pain is a leading health and socioeconomic problem and an unmet need exists for long-lasting analgesics. SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) are required for neuropeptide release and noxious signal transducer surface trafficking, thus, selective expression of the SNARE-cleaving light-chain protease of botulinum neurotoxin A (LCA) in peripheral sensory neurons could alleviate chronic pain. However, a safety concern to this approach is the lack of a sensory neuronal promoter to prevent the expression of LCA in the central nervous system. Towards this, we exploit the unique characteristics of Pirt (phosphoinositide-interacting regulator of TRP), which is expressed in peripheral nociceptive neurons. For the first time, we identified a Pirt promoter element and cloned it into a lentiviral vector driving transgene expression selectively in peripheral sensory neurons. Pirt promoter driven-LCA expression yielded rapid and concentration-dependent cleavage of SNAP-25 in cultured sensory neurons. Moreover, the transcripts of pain-related genes (TAC1, tachykinin precursor 1; CALCB, calcitonin gene-related peptide 2; HTR3A, 5-hydroxytryptamine receptor 3A; NPY2R, neuropeptide Y receptor Y2; GPR52, G protein-coupled receptor 52; SCN9A, sodium voltage-gated channel alpha subunit 9; TRPV1 and TRPA1, transient receptor potential cation channel subfamily V member 1 and subfamily A member 1) in pro-inflammatory cytokines stimulated sensory neurons were downregulated by viral mediated expression of LCA. Furthermore, viral expression of LCA yielded long-lasting inhibition of pain mediator release. Thus, we show that the engineered Pirt-LCA virus may provide a novel means for long lasting pain relief.


Assuntos
Toxinas Botulínicas Tipo A/farmacologia , Neuropeptídeos/metabolismo , Dor/prevenção & controle , Sistema Nervoso Periférico/metabolismo , Células Receptoras Sensoriais/metabolismo , Proteína 25 Associada a Sinaptossoma/metabolismo , Animais , Animais Recém-Nascidos , Feminino , Humanos , Masculino , Fusão de Membrana , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Nociceptores/efeitos dos fármacos , Nociceptores/metabolismo , Dor/genética , Dor/metabolismo , Dor/patologia , Sistema Nervoso Periférico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Células Receptoras Sensoriais/efeitos dos fármacos , Proteína 25 Associada a Sinaptossoma/genética
7.
Heredity (Edinb) ; 123(5): 579-592, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31152165

RESUMO

Marker segregation distortion is a natural phenomenon. Severely distorted markers are usually excluded in the construction of linkage maps. We investigated the effect of marker segregation distortion on linkage map construction and quantitative trait locus (QTL) mapping. A total of 519 recombinant inbred lines of soybean from orthogonal and reciprocal crosses between LSZZH and NN493-1 were genotyped by specific length amplified fragment markers and seed linoleic acid content was measured in three environments. As a result, twenty linkage groups were constructed with 11,846 markers, including 1513 (12.77%) significantly distorted markers, on 20 chromosomes, and the map length was 2475.86 cM with an average marker-interval of 0.21 cM. The inclusion of distorted markers in the analysis was shown to not only improve the grouping of the markers from the same chromosomes, and the consistency of linkage maps with genome, but also increase genome coverage by markers. Combining genotypic data from both orthogonal and reciprocal crosses decreased the proportion of distorted markers and then improved the quality of linkage maps. Validation of the linkage maps was confirmed by the high collinearity between positions of markers in the soybean reference genome and in linkage maps and by the high consistency of 24 QTL regions in this study compared with the previously reported QTLs and lipid metabolism related genes. Additionally, linkage maps that include distorted markers could add more information to the outputs from QTL mapping. These results provide important information for linkage mapping, gene cloning and marker-assisted selection in soybean.


Assuntos
Mapeamento Cromossômico , Ligação Genética , Genótipo , Glycine max/genética , Característica Quantitativa Herdável
8.
Fish Shellfish Immunol ; 63: 181-188, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28214598

RESUMO

Janus kinase (Jak) and signal transducers and activators of transcription (STAT) signaling pathway is associated in antiviral and antibacterial immune response. Previous studies primarily investigated the function of STATs in mammals. For most invertebrates, only one STAT was found in each species, such as STAT92E was found in Drosophila melanogaster. The studies, which focus on the functional difference between various STATs in the same species of invertebrate, are limited. In the present study, three STATs (HcSTAT1, HcSTAT2 and HcSTAT3) were identified in triangle shell pearl mussel, Hyriopsis cumingii. Phylogenetic analysis showed that HcSTAT1 and HcSTAT3 were clustered with Homo sapiens STAT5, and HcSTAT2 was clustered with Pinctada fucata STAT and Crassostea gigas STAT6. All three STATs could be detected in all tested tissues (hemocytes, hepatopancreas, gill, mantle and foot), and were induced expression when challenged with Staphylococcus aureus or Aeromonas hydrophilia in hemocytes and hepatopancreas. HcSTAT1 regulated the expression of HcDef, HcWAP, HcThe and HcTNF. The expression of HcWAP and HcTNF was down-regulated in HcSTAT2-RNAi mussel. And HcSTAT3 affected the expression of HcTNF. The study is the first report of different functions in antibacterial immune responses between STATs in mollusks.


Assuntos
Aeromonas hydrophila/fisiologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Fatores de Transcrição STAT/metabolismo , Staphylococcus aureus/fisiologia , Unionidae/genética , Unionidae/imunologia , Animais , Especificidade de Órgãos , Filogenia , Fatores de Transcrição STAT/genética , Análise de Sequência de DNA , Unionidae/microbiologia
9.
Comput Biol Med ; 170: 108034, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301517

RESUMO

The tensor low-rank prior has attracted considerable attention in dynamic MR reconstruction. Tensor low-rank methods preserve the inherent high-dimensional structure of data, allowing for improved extraction and utilization of intrinsic low-rank characteristics. However, most current methods are still confined to utilizing low-rank structures either in the image domain or predefined transformed domains. Designing an optimal transformation adaptable to dynamic MRI reconstruction through manual efforts is inherently challenging. In this paper, we propose a deep unrolling network that utilizes the convolutional neural network (CNN) to adaptively learn the transformed domain for leveraging tensor low-rank priors. Under the supervised mechanism, the learning of the tensor low-rank domain is directly guided by the reconstruction accuracy. Specifically, we generalize the traditional t-SVD to a transformed version based on arbitrary high-dimensional unitary transformations and introduce a novel unitary transformed tensor nuclear norm (UTNN). Subsequently, we present a dynamic MRI reconstruction model based on UTNN and devise an efficient iterative optimization algorithm using ADMM, which is finally unfolded into the proposed T2LR-Net. Experiments on two dynamic cardiac MRI datasets demonstrate that T2LR-Net outperforms the state-of-the-art optimization-based and unrolling network-based methods.


Assuntos
Aprendizagem , Imageamento por Ressonância Magnética , Algoritmos , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador
10.
Oncol Lett ; 28(2): 351, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38872860

RESUMO

Succinate dehydrogenase (SDH)-deficient renal cell carcinoma (RCC) is an autosomal dominant syndrome caused by heterozygous pathogenic germline variants of the SDH gene. SDH mutations are associated with an increased risk of developing RCC, although studies describing SDH-deficient RCC are currently limited. The present study reported a case of SDH-deficient RCC with high malignancy and rare bone metastasis. The patient was diagnosed with a right renal mass through B-mode ultrasound imaging and showed a carcinoma embolus in the right renal vein and inferior vena cava through kidney contrast-enhanced computed tomography. A whole-body bone scan showed radionuclide accumulation in the upper end of the left humerus, which indicated possible pathological bone destruction. As a result, surgical resection was performed. The postoperative pathology indicated a high-grade RCC and although the specific classification remained uncertain, hereditary leiomyomatosis and RCC was suspected. Subsequently, a germline mutation of the succinate dehydrogenase complex flavoprotein subunit A gene was identified through high-throughput sequencing (c.1A>G, p. Met1?) and immunohistochemistry demonstrated the loss of succinate dehydrogenase complex flavoprotein subunit B expression. Postoperatively, the patient underwent radiotherapy and targeted therapy. After 6 months of follow-up treatment, there was no indication of recurrence or metastasis on thoracoabdominal CT and whole-body bone scintigraphy. Based on the present report, germline screening should potentially be encouraged in early-onset patients as family history or pathological results may not provide sufficient information for the early, differential diagnosis of SDH-deficient RCC.

11.
J Hazard Mater ; 465: 133124, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38142658

RESUMO

In actual lakes, the "unstable components" of macrophyte-derived DOM (MDOM) are always degraded and cannot exist abidingly, but the environmental impact brought by it is ignored. In this study, MDOM from Potamogeton crispus was extracted to carry out microbial combined photodegradation (M-Photodegradation) and fluorescence titration experiments. Then the traits and metal binding reaction of MDOM under M-Photodegradation were analysed and compared with the features of lake-derived DOM (LDOM) from point monitoring of Dongping Lake through EEM-PARAFAC, 2D-SF-COS, and 2D-FTIR-COS. The results showed that the features of MDOM after M-Photodegradation were closer to those of LDOM. The degradation amplitudes were 93.53% ± 0.53% for C4 in microbial degradation and 78.31% ± 0.74% for C3 in photodegradation. Correspondingly, both were hardly detected in LDOM. Protein-like substances and aliphatic C-OH were preferentially selected by Cu2+, while humic-like matter and phenolic hydroxyl O-H responded faster to Pb2+. Although the binding sequences remained unchanged after M-Photodegradation, the LogKCu and LogKPb of components decreased overall, indicating increased environmental risks. This study proves that the refractory MDOM retained after degradation was more consistent with the actual state of macrophytic lakes and provides more information for the treatment of heavy metal pollution in lakes.


Assuntos
Lagos , Chumbo , Espectrometria de Fluorescência/métodos , Lagos/química , Chumbo/análise , Fotólise , Substâncias Húmicas/análise , Análise Fatorial
12.
Chem Sci ; 15(17): 6244-6268, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38699270

RESUMO

Because of its abundant resources, low cost and high reversible specific capacity, hard carbon (HC) is considered as the most likely commercial anode material for sodium-ion batteries (SIBs). Therefore, reasonable design and effective strategies to regulate the structure of HCs play a crucial role in promoting the development of SIBs. Herein, the progress in the preparation approaches for HC anode materials is systematically overviewed, with a special focus on the comparison between traditional fabrication methods and advanced strategies emerged in recent years in terms of their influence on performance, including preparation efficiency, initial coulombic efficiency (ICE), specific capacity and rate capability. Furthermore, the advanced strategies are categorized into two groups: those exhibiting potential for large-scale production to replace traditional methods and those presenting guidelines for achieving high-performance HC anodes from top-level design. Finally, challenges and future development prospects to achieve high-performance HC anodes are also proposed. We believe that this review will provide beneficial guidance to actualize the truly rational design of advanced HC anodes, facilitating the industrialization of SIBs and assisting in formulating design rules for developing high-end advanced electrode materials for energy storage devices.

13.
Int J Biol Macromol ; 261(Pt 2): 129789, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296127

RESUMO

Interactions between polysaccharides and ionic liquids (ILs) at the molecular level are essential to elucidate the dissolution and/or plasticization mechanism of polysaccharides. Herein, saccharide-based ILs (SILs) were synthesized, and cellulose membrane was soaked in different SILs to evaluate the interactions between SILs and cellulose macromolecules. The relevant results showed that the addition of SILs into cellulose can effectively reduce the intra- and/or inter-molecular hydrogen bonds of polysaccharides. Glucose-based IL showed the intensest supramolecular interactions with cellulose macromolecules compared to sucrose- and raffinose-based ILs. Two-dimensional correlation and perturbation-correlation moving window Fourier transform infrared techniques were for the first time used to reveal the dynamic variation of the supramolecular interactions between SILs and cellulose macromolecules. Except for the typical HO⋯H interactions of cellulose itself, stronger -Cl⋯HO hydrogen bonding interactions were detected in the specimen of SILs-modified cellulose membranes. Supramolecular interactions of -Cl⋯H, HO⋯H, C-Cl⋯H, and -C=O⋯H between SILs and cellulose macromolecules sequentially responded to the stimuli of temperature. This work provides a new perspective to understanding the interaction mechanism between polysaccharides and ILs, and an avenue to develop the next-generation ILs for dissolving or thermoplasticizing polysaccharide materials.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Imidazóis/química , Celulose/química , Polissacarídeos , Temperatura
14.
Carcinogenesis ; 34(1): 68-78, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23024267

RESUMO

The morphological detection of early neoplastic transformation leading to cervical cancer remains problematic. In this work, we have identified deleted in split hand/split foot 1 protein (DSS1) as an early biomarker that is specifically upregulated in premalignant and malignant cervical epithelial cells, but is low or undetectable in non-malignant cells. DSS1 mRNA and protein levels are significantly increased in cultured human cervical carcinoma cell lines originating from primary and metastatic tumors. In fact, > 96% of patient tumor tissues were found to have cells with elevated DSS1 when compared with tumor-adjacent normal cells. In histological sections of cervical tissue containing either invasive cervical carcinoma or its precursor lesions, DSS1 was readily detected in the tumor cells. Steady-state DSS1 expression by immortalized cervical cancer cell lines was found to be necessary for maintenance of their transformed phenotype, since stable shRNA-mediated depletion of DSS1 in HeLa cells inhibited their proliferation and colony-forming activity in monolayer cultures and prevented division of these cells in soft agar. When DSS1 levels are reduced using shRNA, the cells ultimately undergo apoptosis via activation of p53 and the p53 downstream targets, and cleavage of apoptosis-associated proteins including CPP32/caspase-3, poly(ADP-ribose)polymerase and DNA-PKcs. In addition, silencing of DSS1 makes cervical cancer cells sensitive to cell death after treatment with cisplatin. We conclude that the DSS1 protein is critically involved in the maintenance of the transformed phenotype in cervical cancer cells, and that it might be a specific, robust and reliable marker for early detection, diagnosis and treatment.


Assuntos
Biomarcadores Tumorais/genética , Complexo de Endopeptidases do Proteassoma/genética , RNA Mensageiro/genética , Neoplasias do Colo do Útero/diagnóstico , Sequência de Bases , Primers do DNA , Feminino , Técnicas de Silenciamento de Genes , Humanos , Reação em Cadeia da Polimerase
15.
Proc Natl Acad Sci U S A ; 107(21): 9596-601, 2010 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-20457940

RESUMO

When G-protein alpha subunits binds GTP and Mg(2+), they transition from their inactive to their active conformation. This transition is accompanied by completion of the coordination shell of Mg(2+) with electrons from six oxygens: two water molecules, the ss and gamma phosphoryls of GTP, a helix-alpha1 Ser, and a switch I domain (SWI) Thr, and the repositioning of SWI and SWII domains. SWII binds and regulates effector enzymes and facilitates GTP hydrolysis by repositioning the gamma-carbonyl of a Gln. Mutating the Ser generates regulatory GTPases that cannot lock Mg(2+) into its place and are locked in their inactive state with dominant negative properties. Curiously, mutating the Thr appears to reduce GTP hydrolysis. The reason for this difference is not known because it is also not known why removal of the Thr should affect the overall GTPase cycle differently than removal of the Ser. Working with recombinant Gsalpha, we report that mutating its SWI-Thr to either Ala, Glu, Gln, or Asp results not only in diminished GTPase activity but also in spontaneous activation of the SWII domain. Upon close examination of existing alpha subunit crystals, we noted the oxygen of the backbone carbonyl of SWI-Thr and of the gamma-carbonyl of SWII Gln to be roughly equidistant from the oxygen of the hydrolytic H(2)O. Our observations indicate that the Gln and Thr carbonyls play equihierarchical roles in the GTPase process and provide the mechanism that explains why mutating the Thr mimics mutating the Gln and not that of the Ser.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Guanosina Trifosfato/metabolismo , Oxigênio/metabolismo , Animais , Cátions Bivalentes/química , Linhagem Celular , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Hidrólise , Magnésio/química , Magnésio/metabolismo , Camundongos , Mutação , Ligação Proteica , Treonina/genética , Treonina/metabolismo
16.
Microorganisms ; 11(6)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37375023

RESUMO

The elevation of the snowline of the No. 1 Glacier in the Tianshan Mountains is increasing due to global warming, which has created favorable conditions for moss invasion and offers an opportunity to investigate the synergistic effects of incipient succession by mosses, plants, and soils. In this study, the concept of altitude distance was used instead of succession time. To investigate the changes of bacterial-community diversity in moss-covered soils during glacial degeneration, the relationship between bacterial community structure and environmental factors was analyzed and valuable microorganisms in moss-covered soils were explored. To do so, the determination of soil physicochemical properties, high-throughput sequencing, the screening of ACC-deaminase-producing bacteria, and the determination of ACC-deaminase activity of strains were performed on five moss-covered soils at different elevations. The results showed that the soil total potassium content, soil available phosphorus content, soil available potassium content, and soil organic-matter content of the AY3550 sample belt were significantly different compared with those of other sample belts (p < 0.05). Secondly, there was a significant difference (p < 0.05) in the ACE index or Chao1 index between the moss-covered-soil AY3550 sample-belt and the AY3750 sample-belt bacterial communities as the succession progressed. The results of PCA analysis, RDA analysis, and cluster analysis at the genus level showed that the community structure of the AY3550 sample belt and the other four sample belts differed greatly and could be divided into two successional stages. The enzyme activities of the 33 ACC-deaminase-producing bacteria isolated and purified from moss-covered soil at different altitudes ranged from 0.067 to 4.7375 U/mg, with strains DY1-3, DY1-4, and EY2-5 having the highest enzyme activities. All three strains were identified as Pseudomonas by morphology, physiology, biochemistry, and molecular biology. This study provides a basis for the changes in moss-covered soil microhabitats during glacial degradation under the synergistic effects of moss, soil, and microbial communities, as well as a theoretical basis for the excavation of valuable microorganisms under glacial moss-covered soils.

17.
Shanghai Kou Qiang Yi Xue ; 32(1): 75-79, 2023 Feb.
Artigo em Zh | MEDLINE | ID: mdl-36973848

RESUMO

PURPOSE: To compare the clinical effect of Er:YAG laser and turbine handpiece in the removal of lower horizontally impacted wisdom teeth, and to evaluate the operation time, postoperative pain, facial swelling, degree of mouth opening limitation and complications. METHODS: From March 2020 to May 2022, forty patients with bilateral lower mandibular horizontally impacted wisdom teeth in the Department of Oral and Maxillofacial Surgery of Linyi People's Hospital were selected,and all bilateral wisdom teeth were partially bone buried. The bilateral wisdom teeth of each patient were removed by Er:YAG laser on one side and turbine handpiece on the other side, respectively. The patients were divided into experimental(laser) group and control(turbine handpiece) group according to the ways of bone removal on each side. The clinical effect of the two groups was compared after a week of follow-up. Statistical analysis was performed with SPSS 19.0 software package. RESULTS: There was no significant difference between the two groups in operation time(P>0.05). The incidence of postoperative pain, facial swelling, mouth opening limitation and complications in the experimental group were significantly lower than those in the control group(P<0.05). CONCLUSIONS: The operation time of extraction with Er:YAG laser is similar to that with turbine handpiece, but laser can reduce postoperative reaction and the incidence of complications, which is easy to be accepted by patients and worthy of wide application.


Assuntos
Lasers de Estado Sólido , Dente Impactado , Humanos , Dente Serotino/cirurgia , Lasers de Estado Sólido/efeitos adversos , Extração Dentária/efeitos adversos , Dente Impactado/cirurgia , Mandíbula/cirurgia , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle
18.
IEEE Trans Image Process ; 32: 4036-4045, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37440404

RESUMO

Transformer, the model of choice for natural language processing, has drawn scant attention from the medical imaging community. Given the ability to exploit long-term dependencies, transformers are promising to help atypical convolutional neural networks to learn more contextualized visual representations. However, most of recently proposed transformer-based segmentation approaches simply treated transformers as assisted modules to help encode global context into convolutional representations. To address this issue, we introduce nnFormer (i.e., not-another transFormer), a 3D transformer for volumetric medical image segmentation. nnFormer not only exploits the combination of interleaved convolution and self-attention operations, but also introduces local and global volume-based self-attention mechanism to learn volume representations. Moreover, nnFormer proposes to use skip attention to replace the traditional concatenation/summation operations in skip connections in U-Net like architecture. Experiments show that nnFormer significantly outperforms previous transformer-based counterparts by large margins on three public datasets. Compared to nnUNet, the most widely recognized convnet-based 3D medical segmentation model, nnFormer produces significantly lower HD95 and is much more computationally efficient. Furthermore, we show that nnFormer and nnUNet are highly complementary to each other in model ensembling. Codes and models of nnFormer are available at https://git.io/JSf3i.

19.
Water Res ; 231: 119605, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36680825

RESUMO

The nature of sediment dissolved organic matter (SDOM) can reflect the environmental background, nutritional status and human activities and is an important part of lakes. The differences in the binding capacity of heavy metals and organic matter in lake sediments with different trophic states at the catchment scale and the mechanism of the differences in binding are still unclear. To solve this problem, we collected bulk SDOMs (< 0.7 µm) from 6 respective lakes (from upstream to downstream) in the Yangtze River Basin (YRB) to qualitatively and quantitatively characterize their properties and metal binding behaviors using excitation-emission matrix spectroscopy combined with parallel factor analysis (EEM-FARAFAC) and two-dimensional correlation spectroscopy of synchronous fluorescence spectroscopy and Fourier transform infrared spectroscopy (2D-SF-COS and 2D-FTIR-COS). The results showed that sediment dissolved organic carbon (SDOC) was mainly enriched in low molecular weight (LMW: < 1 kDa) fractions. The total fluorescence intensity (Fmax) of SDOM from upstream was larger than that from downstream (p = 0.033), and humic-like fluorophores were dominant in these lakes. The Fmax of sediment humic-like components (C1+C2) was closely related to the trophic levels of the lakes. Protein-like substances and oxygen-containing functional groups (C-OH, C=O, and C-O) were preferred in the reaction between SDOM and copper (Cu2+) or cadmium (Cd2+), while a unique binding path was exhibited in the moderately eutrophic DCL. In terms of fluorophore types, higher Cu2+-binding abilities (LogKCu) were observed in the humic-like matter for the lakes in the upper reaches and tryptophan-like matter for the lakes from the midstream and downstream areas of the YRB. Although Cd2+ complexed only with humic-like matter, LogKCd was higher than LogKCu. In terms of molecular weight (MW), the LogKCu/Cd of components were enhanced after MW fractionation. The HMW (0.7 µm - 1 kDa) components possessed higher LogKCu in most lakes (except for CHL and C4). The different fluorophores and molecular weight fractions in SDOM make an important contribution to reducing the ecological risks of heavy metals in lakes.


Assuntos
Matéria Orgânica Dissolvida , Metais Pesados , Cádmio/análise , Substâncias Húmicas/análise , Lagos/química , Metais Pesados/análise , Estado Nutricional , Espectrometria de Fluorescência
20.
Res Child Adolesc Psychopathol ; 51(9): 1343-1355, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37155026

RESUMO

Irritability is a transdiagnostic feature and a common mental health problem in adolescence. Prior studies indicate that irritability is composed of two correlated but separable dimensions, tonic irritability (i.e., irritable mood) and phasic irritability (i.e., temper outbursts), which are respectively associated with internalizing and externalizing outcomes. However, little is known about the stability and interrelations of tonic and phasic irritability. The current study examined the longitudinal interplay between tonic and phasic irritability during adolescence. A community sample of 544 girls (age 13.5-15.5 years) was assessed at 5 waves (over 3 years, in 9-month intervals). A random-intercept cross-lagged panel model was used to examine the within-person stability and longitudinal interrelations of tonic and phasic irritability. Pseudo-indicator models were used to help analyze all available data. Results suggest that tonic and phasic irritability had distinct patterns of development and co-development. Between individuals, tonic and phasic irritability showed moderate rank-order stability and high concurrent correlations. Within individuals, phasic irritability was found to positively predict both tonic and phasic irritability at the subsequent wave, whereas tonic irritability did not predict later phasic irritability and showed weaker within-person stability. These results suggest that increased or decreased phasic irritability in adolescent girls may signify continued increase or decrease in both tonic and phasic irritability. The study was among the first to demonstrate the discriminant validity of tonic and phasic irritability from a developmental perspective.


Assuntos
Humor Irritável , Feminino , Humanos , Adolescente , Estudos Longitudinais
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