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1.
Nat Struct Mol Biol ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658621

RESUMO

The heterogeneity of CARM1 controls first cell fate bias during early mouse development. However, how this heterogeneity is established is unknown. Here, we show that Carm1 mRNA is of a variety of specific exon-skipping splicing (ESS) isoforms in mouse two-cell to four-cell embryos that contribute to CARM1 heterogeneity. Disruption of paraspeckles promotes the ESS of Carm1 precursor mRNAs (pre-mRNAs). LincGET, but not Neat1, is required for paraspeckle assembly and inhibits the ESS of Carm1 pre-mRNAs in mouse two-cell to four-cell embryos. We further find that LincGET recruits paraspeckles to the Carm1 gene locus through HNRNPU. Interestingly, PCBP1 binds the Carm1 pre-mRNAs and promotes its ESS in the absence of LincGET. Finally, we find that the ESS seen in mouse two-cell to four-cell embryos decreases CARM1 protein levels and leads to trophectoderm fate bias. Our findings demonstrate that alternative splicing of CARM1 has an important role in first cell fate determination.

2.
Mater Today Bio ; 25: 101020, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38500558

RESUMO

Surgery followed by adjuvant chemotherapy or radiation therapy remains the mainstream treatment for breast cancer in the clinic. However, cancer recurrence post surgery is still common. In view of the clinical practice that autologous fat tissue grafting is often used to facilitate breast reconstruction after lumpectomy, here we develop an in vivo targetable adipocyte-based drug depot for the prevention of post-surgical cancer recurrence. We show that primary adipocytes can be metabolically labeled with clickable chemical tags (e.g., azido groups), for subsequent conjugation of dibenzocyclooctyne (DBCO)-bearing cargo via efficient click chemistry. The conjugated cargo can retain well on the adipocyte membrane. By incorporating a cleavable linker between DBCO and cargo, the conjugated cargo can be gradually released from the surface of adipocytes to effect on neighboring cells. In the context of breast cancer surgery, azido-labeled adipocytes grafted to the surgical site can capture circulating DBCO-drugs for improved prevention of 4T1 triple-negative breast cancer (TNBC) recurrence and metastasis. This targetable and refillable adipocyte-based drug depot holds great promise for drug delivery, transplantation, and other applications.

3.
Small ; : e2400013, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433394

RESUMO

Ruddlesden-Popper (RP) interface with defined stacking structure will fundamentally influence the optoelectronic performances of lead-halide perovskite (LHP) materials and devices. However, it remains challenging to observe the atomic local structures in LHPs, especially for multi-dimensional RP interface hidden inside the nanocrystal. In this work, the advantages of two imaging modes in scanning transmission electron microscopy (STEM), including high-angle annular dark field (HAADF) and integrated differential phase contrast (iDPC) STEM, are successfully combined to study the bulk and local structures of inorganic and organic/inorganic hybrid LHP nanocrystals. Then, the multi-dimensional RP interfaces in these LHPs are atomically resolved with clear gap and blurred transition region, respectively. In particular, the complex interface by the RP stacking in 3D directions can be analyzed in 2D projected image. Finally, the phase transition, ion missing, and electronic structures related to this interface are investigated. These results provide real-space evidence for observing and analyzing atomic multi-dimensional RP interfaces, which may help to better understand the structure-property relation of LHPs, especially their complex local structures.

4.
J Integr Plant Biol ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477647

RESUMO

The evolution of the latitudinal diversity gradient (LDG), characterized by a peak in diversity toward the tropics, has captured significant attention in evolutionary biology and ecology. However, the inverse LDG (i-LDG) mechanism, wherein species richness increases toward the poles, remains inadequately explored. Cycads are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the tropics. Intriguingly, the extant cycad abundance exhibits an i-LDG pattern, and the underlying causes for this phenomenon remain largely elusive. Here, using 1,843 nuclear genes from a nearly complete sampling, we conducted comprehensive phylogenomic analyses to establish a robust species-level phylogeny for Cycas, the largest genus within cycads. We then reconstructed the spatial-temporal dynamics and integrated global environmental data to evaluate the roles of species ages, diversification rates, contemporary environment, and conservatism to ancestral niches in shaping the i-LDG pattern. We found Cycas experienced decreased diversification rates, coupled with the cooling temperature since its origin in the Eocene from continental Asia. Different regions have distinctively contributed to the formation of i-LDG for Cycas, with the northern hemisphere acting as evolutionary museums and the southern hemisphere serving as cradles. Moreover, water-related climate variables, specifically precipitation seasonality and potential evapotranspiration, were identified as paramount factors constraining Cycas species richness in the rainforest biome near the equator. Notably, the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity pattern. This study underscores the imperative of integrating both evolutionary and ecological approaches to comprehensively unravel the mechanisms underpinning global biodiversity patterns.

5.
Mol Pharm ; 21(3): 1182-1191, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38323546

RESUMO

The chemical structure of excipients molecularly mixed in an amorphous solid dispersion (ASD) has a significant impact on properties of the ASD including dissolution behavior, physical stability, and bioavailability. Polymers used in ASDs require a balance between hydrophobic and hydrophilic functionalities to ensure rapid dissolution of the amorphous dispersion as well as sustained supersaturation of the drug in solution. This work demonstrates the use of postpolymerization functionalization of poly(vinylpyridine) excipients to elucidate the impact of polymer properties on the dissolution behavior of amorphous dispersions containing posaconazole. It was found that N-oxidation of pyridine functionalities increased the solubility of poly(vinylpyridine) derivatives in neutral aqueous conditions and allowed for nanoparticle formation which supplied posaconazole into solution at concentrations exceeding those achieved by more conventional excipients such as hydroxypropyl methylcellulose acetate succinate (HPMCAS) or Eudragit E PO. By leveraging these functional modifications of the parent poly(vinylpyridine) excipient to increase polymer hydrophilicity and minimize the effect of polymer on pH, a new polymeric excipient was optimized for rapid dissolution and supersaturation maintenance for a model compound.


Assuntos
Excipientes , Óxidos , Triazóis , Excipientes/química , Solubilidade , Polímeros/química , Metilcelulose
6.
Small Methods ; : e2301617, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368262

RESUMO

The lead iodide (PbI2 ) in lead-halide perovskite (LHP) is both a positive additive for material properties and a site for the formation of device defects. Therefore, atomic-level detection of PbI2 and its derived Pb structures are crucial for understanding the performance and stability of the LHP material. In this work, the atomic imaging of the LHP, PbI2 , and Pb lattices is achieved using low-dose integrated differential phase contrast (iDPC) scanning transmission electron microscopy (STEM). Combining it with the traditional high-angle annular dark field (HAADF)-STEM, the Pb precipitation in different LHPs (CsPbI3 , CsPbBr3, and FAPbI3 ) and under different conditions (light, air, and heat) can be investigated in real space. Then, the features of Pb precipitation (positions and sizes) are visually revealed under different conditions and the stabilities of different LHPs. Meanwhile, the pathway of Pb precipitation is directly imaged and confirmed by the iDPC-STEM during an in situ heating process, supporting the detailed mechanism of Pb precipitation. These results provide the visual evidence for analyzing atomic Pb precipitation in LHPs, which helps better understand the structure-property relation induced by Pb impurity.

7.
Appl Opt ; 63(3): 549-556, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38294364

RESUMO

Single-pixel imaging, renowned for its high sensitivity, robustness against interference, and superior resolution, has become increasingly prominent in the field of optical research. Over recent years, a diverse array of light modulation devices and methodologies has been devised to accomplish megahertz modulations rates. This work presents a single-pixel imaging scheme based on the fuzzy coding of metasurfaces. This unique encoding technique manipulates the quality of the mask pattern by adjusting the pixel count within the metasurface units. Notably, we expand the metasurface units to effectively mitigate the position sensitivity during movement or rotations, thus easing the challenge for the detector in collecting the correct light intensity during sub-mask transitions. A detailed analysis is drawn of the reconstruction quality of fuzzy masks. Simultaneously, we provide simulations of single-pixel imaging under the condition where the fuzzy-coded metasurface is moving. This work provides a new, to the best of our knowledge, mask generation mode for high-speed spatial light modulation.

8.
Comput Biol Med ; 168: 107725, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38006827

RESUMO

Delineating lesion boundaries play a central role in diagnosing thyroid and breast cancers, making related therapy plans and evaluating therapeutic effects. However, it is often time-consuming and error-prone with limited reproducibility to manually annotate low-quality ultrasound (US) images, given high speckle noises, heterogeneous appearances, ambiguous boundaries etc., especially for nodular lesions with huge intra-class variance. It is hence appreciative but challenging for accurate lesion segmentations from US images in clinical practices. In this study, we propose a new densely connected convolutional network (called MDenseNet) architecture to automatically segment nodular lesions from 2D US images, which is first pre-trained over ImageNet database (called PMDenseNet) and then retrained upon the given US image datasets. Moreover, we also designed a deep MDenseNet with pre-training strategy (PDMDenseNet) for segmentation of thyroid and breast nodules by adding a dense block to increase the depth of our MDenseNet. Extensive experiments demonstrate that the proposed MDenseNet-based method can accurately extract multiple nodular lesions, with even complex shapes, from input thyroid and breast US images. Moreover, additional experiments show that the introduced MDenseNet-based method also outperforms three state-of-the-art convolutional neural networks in terms of accuracy and reproducibility. Meanwhile, promising results in nodular lesion segmentation from thyroid and breast US images illustrate its great potential in many other clinical segmentation tasks.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Humanos , Reprodutibilidade dos Testes , Processamento de Imagem Assistida por Computador/métodos , Ultrassonografia/métodos , Mama
9.
Trends Pharmacol Sci ; 45(1): 56-66, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38071088

RESUMO

Cancer stem cells (CSCs) are a small subpopulation of cancer cells with capabilities of self-renewal, differentiation, and tumorigenicity, and play a critical role in driving tumor heterogeneity that evolves insensitivity to therapeutics. For these reasons, extensive efforts have been made to identify and target CSCs to potentially improve the antitumor efficacy of therapeutics. While progress has been made to uncover certain CSC-associated biomarkers, the identification of CSC-specific markers, especially the targetable ones, remains a significant challenge. Here we provide an overview of the unique signaling and metabolic pathways of CSCs, summarize existing CSC biomarkers and CSC-targeted therapies, and discuss strategies to further differentiate CSCs from non-stem cancer cells and healthy cells for the development of enhanced CSC-targeted therapies.


Assuntos
Neoplasias , Humanos , Neoplasias/metabolismo , Biomarcadores/metabolismo , Células-Tronco Neoplásicas/patologia , Transdução de Sinais , Diferenciação Celular , Biomarcadores Tumorais/metabolismo
10.
Nat Commun ; 14(1): 8047, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052869

RESUMO

As key mediators of cellular communication, extracellular vesicles (EVs) have been actively explored for diagnostic and therapeutic applications. However, effective methods to functionalize EVs and modulate the interaction between EVs and recipient cells are still lacking. Here we report a facile and universal metabolic tagging technology that can install unique chemical tags (e.g., azido groups) onto EVs. The surface chemical tags enable conjugation of molecules via efficient click chemistry, for the tracking and targeted modulation of EVs. In the context of tumor EV vaccines, we show that the conjugation of toll-like receptor 9 agonists onto EVs enables timely activation of dendritic cells and generation of superior antitumor CD8+ T cell response. These lead to 80% tumor-free survival against E.G7 lymphoma and 33% tumor-free survival against B16F10 melanoma. Our study yields a universal technology to generate chemically tagged EVs from parent cells, modulate EV-cell interactions, and develop potent EV vaccines.


Assuntos
Vacinas Anticâncer , Vesículas Extracelulares , Neoplasias Cutâneas , Humanos , Vacinas Anticâncer/metabolismo , Vesículas Extracelulares/metabolismo , Comunicação Celular , Neoplasias Cutâneas/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-38082702

RESUMO

In surgery-based renal cancer treatment, one of the most essential tasks is the three-dimensional (3D) kidney parsing on computed tomography angiography (CTA) images. In this paper, we propose an end-to-end convolutional neural network-based framework to segment multiple renal structures, including kidneys, kidney tumors, arteries, and veins from arterial-phase CT images. Our method consists of two collaborative modules: First, we propose an encoding-decoding network, named Multi-Branch Dilated Convolutional Network (MBD-Net), consisting of residual, hybrid dilated convolutional, and reduced-dimensional convolutional structures, which improves the feature extraction ability with relatively fewer network parameters. Given that renal tumors and cysts have confusing geometric structures, we also design the Cyst Discriminator to effectively distinguish tumors from cysts without labeling information via gray-scale curves and radiographic features. We have quantitatively evaluated our approach on a publicly available dataset from MICCAI 2022 Kidney Parsing for Renal Cancer Treatment Challenge (KiPA2022), with mean Dice similarity coefficient (DSC) as 96.18%, 90.99%, 88.66% and 80.35% for the kidneys, kidney tumors, arteries, and veins respectively, winning the stable and top performance in the challenge.Clinical relevance-The proposed CNN-Based framework can automatically segment 3D kidneys, renal tumors, arteries, and veins for kidney parsing techniques, benefiting surgery-based renal cancer treatment.


Assuntos
Cistos , Neoplasias Renais , Humanos , Redes Neurais de Computação , Angiografia por Tomografia Computadorizada , Rim/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem
12.
Sports Med Open ; 9(1): 89, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37747653

RESUMO

BACKGROUND: The effects of hypoxia conditioning, which involves recurrent exposure to hypoxia combined with exercise training, on improving body composition in the ageing population have not been extensively investigated. OBJECTIVE: This meta-analysis aimed to determine if hypoxia conditioning, compared to similar training near sea level, maximizes body composition benefits in middle-aged and older adults. METHODS: A literature search of PubMed, EMBASE, Web of Science, Scopus and CNKI (China National Knowledge Infrastructure) databases (up to 27th November 2022) was performed, including the reference lists of relevant papers. Three independent reviewers extracted study characteristics and health outcome measures. Search results were limited to original studies of the effects of hypoxia conditioning on body composition in middle-aged and older adults. RESULTS: Twelve studies with a total of 335 participants were included. Hypoxia conditioning induced greater reductions in body mass index (MD = -0.92, 95%CI: -1.28 to -0.55, I2 = 0%, p < 0.00001) and body fat (SMD = -0.38, 95%CI: -0.68 to -0.07, I2 = 49%, p = 0.01) in middle-aged and older adults compared with normoxic conditioning. Hypoxia conditioning improved lean mass with this effect not being larger than equivalent normoxic interventions in either middle-aged or older adults (SMD = 0.07, 95%CI -0.12 to 0.25, I2 = 0%, p = 0.48). Subgroup analysis showed that exercise in moderate hypoxia (FiO2 > 15%) had larger effects than more severe hypoxia (FiO2 ≤ 15%) for improving body mass index in middle-aged and older adults. Hypoxia exposure of at least 60 min per session resulted in larger benefits for both body mass index and body fat. CONCLUSION: Hypoxia conditioning, compared to equivalent training in normoxia, induced greater body fat and body mass index improvements in middle-aged and older adults. Adding hypoxia exposure to exercise interventions is a viable therapeutic solution to effectively manage body composition in ageing population.

13.
J Med Internet Res ; 25: e44897, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37698914

RESUMO

BACKGROUND: The innovative method of sentiment analysis based on an emotional lexicon shows prominent advantages in capturing emotional information, such as individual attitudes, experiences, and needs, which provides a new perspective and method for emotion recognition and management for patients with breast cancer (BC). However, at present, sentiment analysis in the field of BC is limited, and there is no emotional lexicon for this field. Therefore, it is necessary to construct an emotional lexicon that conforms to the characteristics of patients with BC so as to provide a new tool for accurate identification and analysis of the patients' emotions and a new method for their personalized emotion management. OBJECTIVE: This study aimed to construct an emotional lexicon of patients with BC. METHODS: Emotional words were obtained by merging the words in 2 general sentiment lexicons, the Chinese Linguistic Inquiry and Word Count (C-LIWC) and HowNet, and the words in text corpora acquired from patients with BC via Weibo, semistructured interviews, and expressive writing. The lexicon was constructed using manual annotation and classification under the guidance of Russell's valence-arousal space. Ekman's basic emotional categories, Lazarus' cognitive appraisal theory of emotion, and a qualitative text analysis based on the text corpora of patients with BC were combined to determine the fine-grained emotional categories of the lexicon we constructed. Precision, recall, and the F1-score were used to evaluate the lexicon's performance. RESULTS: The text corpora collected from patients in different stages of BC included 150 written materials, 17 interviews, and 6689 original posts and comments from Weibo, with a total of 1,923,593 Chinese characters. The emotional lexicon of patients with BC contained 9357 words and covered 8 fine-grained emotional categories: joy, anger, sadness, fear, disgust, surprise, somatic symptoms, and BC terminology. Experimental results showed that precision, recall, and the F1-score of positive emotional words were 98.42%, 99.73%, and 99.07%, respectively, and those of negative emotional words were 99.73%, 98.38%, and 99.05%, respectively, which all significantly outperformed the C-LIWC and HowNet. CONCLUSIONS: The emotional lexicon with fine-grained emotional categories conforms to the characteristics of patients with BC. Its performance related to identifying and classifying domain-specific emotional words in BC is better compared to the C-LIWC and HowNet. This lexicon not only provides a new tool for sentiment analysis in the field of BC but also provides a new perspective for recognizing the specific emotional state and needs of patients with BC and formulating tailored emotional management plans.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Análise de Sentimentos , Emoções , Medo , Tristeza
14.
Nat Commun ; 14(1): 5049, 2023 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-37598185

RESUMO

Dendritic cell (DC) vaccine was among the first FDA-approved cancer immunotherapies, but has been limited by the modest cytotoxic T lymphocyte (CTL) response and therapeutic efficacy. Here we report a facile metabolic labeling approach that enables targeted modulation of adoptively transferred DCs for developing enhanced DC vaccines. We show that metabolic glycan labeling can reduce the membrane mobility of DCs, which activates DCs and improves the antigen presentation and subsequent T cell priming property of DCs. Metabolic glycan labeling itself can enhance the antitumor efficacy of DC vaccines. In addition, the cell-surface chemical tags (e.g., azido groups) introduced via metabolic glycan labeling also enable in vivo conjugation of cytokines onto adoptively transferred DCs, which further enhances CTL response and antitumor efficacy. Our DC labeling and targeting technology provides a strategy to improve the therapeutic efficacy of DC vaccines, with minimal interference upon the clinical manufacturing process.


Assuntos
Polissacarídeos , Vacinas , Membrana Celular , Membranas , Células Dendríticas
15.
ACS Omega ; 8(30): 27293-27299, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37546628

RESUMO

Co3O4, as the support of single-atom catalysts, is effective in electron-structure modulation to get distinct methanol adsorption behaviors and adjustable reaction pathways for the methanol oxidation reaction. Herein, we considered the facets that constitute a Co vacancy of the Co3O4(111) facet and a foreign metal atom M (M = Fe, Ni, Cu, Ru, Rh, Pd, Ag, Os, Ir, Pt, Au, Mn) leading to single-atom catalysts. The Mn1@Co3O4(111) facet is the facet considered the most favorable among all of the possible terminations. Oxygen adsorption, decomposition, and its co-adsorption with methanol are the vital steps of methanol oxidation at the exposed Mn1@Co3O4(111) facet, giving rise to the stable configuration: two O* and one CH3OH* adsorbates. Then, the Mn1@Co3O4(111) facet activates the O-H and C-H bonds within CH3OH*, advances CH3O* → H2CO* → HCOO* → COO*, and releases the products H2, H2O, and CO2 consecutively.

16.
Int J Mol Sci ; 24(15)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37569884

RESUMO

The liver plays a crucial role in preserving the homeostasis of an entire organism by metabolizing both endogenous and exogenous substances, a process that relies on the harmonious interactions of hepatocytes, hepatic stellate cells (HSCs), Kupffer cells (KCs), and vascular endothelial cells (ECs). The disruption of the liver's normal structure and function by diverse pathogenic factors imposes a significant healthcare burden. At present, most of the treatments for liver disease are palliative in nature, rather than curative or restorative. Transient receptor potential (TRP) channels, which are extensively expressed in the liver, play a crucial role in regulating intracellular cation concentration and serve as the origin or intermediary stage of certain signaling pathways that contribute to liver diseases. This review provides an overview of recent developments in liver disease research, as well as an examination of the expression and function of TRP channels in various liver cell types. Furthermore, we elucidate the molecular mechanism by which TRP channels mediate liver injury, liver fibrosis, and hepatocellular carcinoma (HCC). Ultimately, the present discourse delves into the current state of research and extant issues pertaining to the targeting of TRP channels in the treatment of liver diseases and other ailments. Despite the numerous obstacles encountered, TRP channels persist as an extremely important target for forthcoming clinical interventions aimed at treating liver diseases.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Canais de Potencial de Receptor Transitório , Humanos , Canais de Potencial de Receptor Transitório/metabolismo , Células Endoteliais/metabolismo
17.
Int J Cardiol ; 387: 131129, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37355242

RESUMO

OBJECTIVE: To investigate clinical features and outcomes of Chinese patients with Takotsubo syndrome (TTS). METHODS: We established the first Chinese Registry of Takotsubo Syndrome (ChiTTS Registry) and analyzed demographic, clinical, therapeutical, and outcome data to characterize clinical and outcome features of Chinese TTS patients. RESULTS: In 112 enrolled patients in the ChiTTS registry from 02/01/2016 to 12/28/2021, the mean age was 59.4 ± 18.7 years old, and 27.7% were men. A total of 41.1% patients experienced respiratory and circulatory complications during hospitalization, and 17.3% patients developed cardiogenic shock. Physical triggers, dyspnea, tachycardia, and younger age (< 70 years old) predicted in-hospital complications. The MACCE rate during follow up was 13.9% per patient per year and the rate of all-cause death was 12.8% per patient per year. TTS patients with in-hospital complications developed more long-term MACCE (24.6% vs. 6.6% per patient-year, P < 0.001) and higher all-cause mortality (21.9% vs. 6.6% per patient-year, P = 0.001) than those without. The Kaplan-Meier survival analysis showed that more MACCE occurred in TTS patients with tachycardia during 3-year follow-up (HR 4.18; 95% CI 1.80-9.74; log-rank test P < 0.001). Among all medications at discharge, only beta-blocker was associated with reduced long-term MACCE (HR: 0.35; 95% CI: 0.12-0.996; P = 0.049). CONCLUSION: We investigated clinical and outcome features of patients in the first Chinese TTS Registry. Tachycardiac TTS patients developed more inpatient and long-term adverse cardiovascular events.


Assuntos
Cardiomiopatia de Takotsubo , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Cardiomiopatia de Takotsubo/diagnóstico , Cardiomiopatia de Takotsubo/epidemiologia , População do Leste Asiático , Choque Cardiogênico , Pacientes Internados , Sistema de Registros
18.
Gels ; 9(5)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37233022

RESUMO

Silk fibroin (SF) is an excellent protein-based biomaterial produced by the degumming and purification of silk from cocoons of the Bombyx mori through alkali or enzymatic treatments. SF exhibits excellent biological properties, such as mechanical properties, biocompatibility, biodegradability, bioabsorbability, low immunogenicity, and tunability, making it a versatile material widely applied in biological fields, particularly in tissue engineering. In tissue engineering, SF is often fabricated into hydrogel form, with the advantages of added materials. SF hydrogels have mostly been studied for their use in tissue regeneration by enhancing cell activity at the tissue defect site or counteracting tissue-damage-related factors. This review focuses on SF hydrogels, firstly summarizing the fabrication and properties of SF and SF hydrogels and then detailing the regenerative effects of SF hydrogels as scaffolds in cartilage, bone, skin, cornea, teeth, and eardrum in recent years.

19.
Front Public Health ; 11: 1114139, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36817918

RESUMO

Background: Receiving a breast cancer diagnosis and treatment is both a physical and emotional journey. Previous studies using single-source data have revealed common and culture-specific emotional experiences of patients living with breast cancer. However, few studies have combined such data from multiple sources. Thus, using a variety of data sources, the current study sought to explore the emotional experiences of women in China newly diagnosed, post-operative, or undergoing chemotherapy. We posited that even though women living with breast cancer in China have multiple channels through which they can express these emotional experiences, little variance would be found in their emotional expressivity and the themes they want to express due to cultural inhibitions. Methods: Text data from female patients newly diagnosed, post-operative, or undergoing chemotherapy were collected between June 2021 and January 2022 via a Python web crawler, semi-structured interviews, and an expressive writing intervention. Data were transcribed and subjected to thematic analysis. Reporting followed the consolidated criteria for reporting qualitative studies (COREQ) guidelines. Results: Analyses were based on 5,675 Weibo posts and comments published by 448 posters and 1,842 commenters, transcription texts from 17 semi-structured interviews, and 150 expressive writing texts. From this total collection of 461,348 Chinese characters, three major themes emerged: (i) conflicting emotions after diagnosis; (ii) long-term suffering and treatment concerns; and (iii) benefit finding and cognitive reappraisal. Conclusions: Despite gathering information from various sources, we found that distress from body-image disturbances, gender role loss and conflict, and changes in sexuality and fertility, were consistent among this sample of female Chinese patients with breast cancer. However, when women engaged actively in benefit finding and cognitive reappraisal with strong social support, patients were able to find ways to adapt and reported post-traumatic growth. Strong social support was an important facilitator in this growth. These study findings emphasize that healthcare professionals ought to increase cultural sensitivity, provide multiple channels to encourage patients to express their emotions, and incorporate screening for patients' emotional distress at all diagnostic and treatment phases as part of routine nursing care.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Emoções , China
20.
Nat Struct Mol Biol ; 30(2): 200-215, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36646905

RESUMO

Poly(A)-tail-mediated post-transcriptional regulation of maternal mRNAs is vital in the oocyte-to-embryo transition (OET). Nothing is known about poly(A) tail dynamics during the human OET. Here, we show that poly(A) tail length and internal non-A residues are highly dynamic during the human OET, using poly(A)-inclusive RNA isoform sequencing (PAIso-seq). Unexpectedly, maternal mRNAs undergo global remodeling: after deadenylation or partial degradation into 3'-UTRs, they are re-polyadenylated to produce polyadenylated degradation intermediates, coinciding with massive incorporation of non-A residues, particularly internal long consecutive U residues, into the newly synthesized poly(A) tails. Moreover, TUT4 and TUT7 contribute to the incorporation of these U residues, BTG4-mediated deadenylation produces substrates for maternal mRNA re-polyadenylation, and TENT4A and TENT4B incorporate internal G residues. The maternal mRNA remodeling is further confirmed using PAIso-seq2. Importantly, maternal mRNA remodeling is essential for the first cleavage of human embryos. Together, these findings broaden our understanding of the post-transcriptional regulation of maternal mRNAs during the human OET.


Assuntos
Oócitos , RNA Mensageiro Estocado , Humanos , RNA Mensageiro Estocado/metabolismo , Oócitos/metabolismo , RNA Mensageiro/metabolismo , Regulação da Expressão Gênica , Poliadenilação , Poli A/química
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