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1.
Langmuir ; 40(17): 8897-8910, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38626396

RESUMO

MXene-inspired two-dimensional (2D) materials like Ti3C2Tx are widely known for their versatile properties, including surface plasmon, higher electrical conductivity, exceptional in-plane tensile strength, EMI shielding, and IR thermal properties. The MXene nanosheets coupled poly(vinylidene fluoride) (PVDF) nanofibers with d33 ∼-26 pm V-1 are able to capture the smaller thermal fluctuation due to a superior pyroelectric coefficient of ∼130 nC m-2 K-1 with an improved (∼7 times with respect to neat PVDF nanofibers) pyroelectric current figure of merit (FOMi). The significant enhancement of the pyroelectric response is attributed to the confinement effect of 2D MXene (Ti3C2Tx) nanosheets within PVDF nanofibers, as evidenced from polarized Fourier transform infrared (FTIR) spectroscopy and scanning probe microscopy (SPM). In subsequent studies, the practical applications of self-powered pyroelectric sensors of MXene-PVDF have been demonstrated. The fabricated flexible, hydrophobic pyroelectric sensor could be utilized as an excellent pyroelectric breathing sensor, a proximity sensor, and an IR data transmission receiver. Further, supervised machine learning algorithms are proposed to distinguish different types of breathing signals with ∼98% accuracy for healthcare monitoring purposes.

2.
PLoS One ; 19(2): e0298427, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38358993

RESUMO

BACKGROUND: Generative Artificial Intelligence (AI) technology, for instance Chat Generative Pre-trained Transformer (ChatGPT), is continuously evolving, and its userbase is growing. These technologies are now being experimented by the businesses to leverage their potential and minimise their risks in business operations. The continuous adoption of the emerging Generative AI technologies will help startups gain more and more experience with adoptions, helping them to leverage continuously evolving technological innovation landscape. However, there is a dearth of prior research on ChatGPT adoption in the startup context, especially from Entrepreneur perspective, highlights the urgent need for a thorough investigation to identify the variables influencing this technological adoption. The primary objective of this study is to ascertain the factors that impact the uptake of ChatGPT technology by startups, anticipate their influence on the triumph of companies, and offer pragmatic suggestions for various stakeholders, including entrepreneurs, and policymakers. METHOD AND ANALYSIS: This study attempts to explore the variables impacting startups' adoption of ChatGPT technology, with an emphasis on comprehending entrepreneurs' attitudes and perspectives. To identify and then empirically validate the Generative AI technology adoption framework, the study uses a two-stage methodology that includes experience-based research, and survey research. The research method design is descriptive and Correlational design. Stage one of the research study is descriptive and involves adding practical insights, and real-world context to the model by drawing from the professional consulting experiences of the researchers with the SMEs. The outcome of this stage is the adoption model (also called as research framework), building Upon Technology Adoption Model (TAM), that highlight the technology adoption factors (also called as latent variables) connected with subset of each other and finally to the technology adoption factor (or otherwise). Further, the latent variables and their relationships with other latent variables as graphically highlighted by the adoption model will be translated into the structured questionnaire. Stage two involves survey based research. In this stage, structured questionnaire is tested with small group of entrepreneurs (who has provided informed consent) and finally to be distributed among startup founders to further validate the relationships between these factors and the level of influence individual factors have on overall technology adoption. Partial Least Squares Structural Equation Modeling (PLS-SEM) will be used to analyze the gathered data. This multifaceted approach allows for a comprehensive analysis of the adoption process, with an emphasis on understanding, describing, and correlating the key elements at play. DISCUSSION: This is the first study to investigate the factors that impact the adoption of Generative AI, for instance ChatGPT technology by startups from the Entrepreneurs perspectives. The study's findings will give Entrepreneurs, Policymakers, technology providers, researchers, and Institutions offering support for entrepreneurs like Academia, Incubators and Accelerators, University libraries, public libraries, chambers of commerce, and foreign embassies important new information that will help them better understand the factors that encourage and hinder ChatGPT adoption. This will allow them to make well-informed strategic decisions about how to apply and use this technology in startup settings thereby improving their services for businesses.


Assuntos
Inteligência Artificial , Tecnologia , Humanos , Transporte Biológico , Colina O-Acetiltransferase , Comércio
3.
Biomater Sci ; 12(7): 1801-1821, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407241

RESUMO

The degeneration of neurons due to the accumulation of misfolded amyloid aggregates in the central nervous system (CNS) is a fundamental neuropathology of Alzheimer's disease (AD). It is believed that dislodging/clearing these amyloid aggregates from the neuronal tissues could lead to a potential cure for AD. In the present work, we explored biocompatible polydopamine-coated piezoelectric polyvinylidene fluoride (DPVDF) nanospheres as acoustic stimulus-triggered anti-fibrillating and anti-amyloid agents. The nanospheres were tested against two model amyloidogenic peptides, including the reductionist model-based amyloidogenic dipeptide, diphenylalanine, and the amyloid polypeptide, amyloid beta (Aß42). Our results revealed that DPVDF nanospheres could effectively disassemble the model peptide-derived amyloid fibrils under suitable acoustic stimulation. In vitro studies also showed that the stimulus activated DPVDF nanospheres could efficiently alleviate the neurotoxicity of FF fibrils as exemplified in neuroblastoma, SHSY5Y, cells. Studies carried out in animal models further validated that the nanospheres could dislodge amyloid aggregates in vivo and also help the animals regain their cognitive behavior. Thus, these acoustic stimuli-activated nanospheres could serve as a novel class of disease-modifying nanomaterials for non-invasive electro-chemotherapy of Alzheimer's disease.


Assuntos
Doença de Alzheimer , Nanosferas , Animais , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Amiloide , Modelos Animais de Doenças
4.
Angew Chem Int Ed Engl ; 63(5): e202316786, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38058265

RESUMO

Achieving increased energy density under extreme operating conditions remains a major challenge in rechargeable batteries. Herein, we demonstrate an all-fluorinated ester-based electrolyte comprising partially fluorinated carboxylate and carbonate esters. This electrolyte exhibits temperature-resilient physicochemical properties and moderate ion-paired solvation, leading to a half solvent-separated and half contact-ion pair in a sole electrolyte. As a result, facile desolvation and preferential reduction of anions/fluorinated co-solvents for LiF-dominated interphases are achieved without compromising ionic conductivity (>1 mS cm-1 even at -40 °C). These advantageous features were found to apply to both lithium metal and sulfur-based electrodes even under extreme operating conditions, allowing stable cycling of Li || sulfurized polyacrylonitrile (SPAN) full cells with high SPAN loading (>3.5 mAh cm-2 ) and thin Li anode (50 µm) at -40, 23 and 50 °C. This work offers a promising path for designing temperature-resilient electrolytes to support high energy density Li metal batteries operating in extreme conditions.

5.
ACS Appl Mater Interfaces ; 15(37): 43724-43731, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37695100

RESUMO

Sulfurized polyacrylonitrile (SPAN) is considered as a high-value cathode material, which leverages the high energy of S redox while mitigating the negative externalities that limit elemental S cycling. As such, the sulfur content in Li-SPAN batteries plays a critical role. In this work, we demonstrate that high-S loading SPAN cathodes, where the PAN backbone approaches the saturation point without signs of elemental S, are highly dependent on the electrolyte chemistry for long-term reversibility. Specifically, we find that a localized-high-concentration electrolyte (LHCE) further enhances the reversible capacity and cycling stability of SPAN cathode with optimized S content relative to a carbonate control, largely due to the formation of a compatible interphase. With this LHCE as the electrolyte and 43% sulfur ratio of SPAN as the cathode, a full cell applying N/P ratio = 1.82, a cathode loading of 6 mAh cm-2 (9.2 mg cm-2), and an electrolyte loading of 7 µL mg-1 SPAN can be cycled for 100 cycles with 433 mAh g-1 retained capacity and retains much of this reversibility even at 60 °C. This work reveals the molecular origin of optimized sulfur ratio in SPAN cathodes while providing guidance in electrolyte design for Li||SPAN cells with high capacity and cyclability.

7.
Int J Appl Basic Med Res ; 13(1): 5-9, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37266525

RESUMO

Background: Current severity assessment scores of acute pancreatitis (AP) include multiple variables, the results of which are available only after 48 h of admission. Red cell distribution width (RDW) and total serum calcium (TSC) are simple routine parameters related to inflammatory status and results of which are readily available. Aim: The aim of this study was to evaluate RDW and RDW: TSC within 24 h of hospital admission as predictors of outcome (severity and mortality) and intervention (medical/percutaneous drainage/surgical) required by patients of AP. Materials and Methods: All the patients diagnosed with AP at a tertiary care hospital were enrolled for the study. Values of RDW and TSC along with data regarding the treatment given were collected. Diagnosis and severity were defined according to the revised Atlanta classification 2012. Results and Interpretation: Cutoff value for RDW (area under the receiver operating characteristic curve [AUROC]: 0.997; P = 0.000) to predict the severity of AP was 16.25% (sensitivity - 100% and specificity - 97.1%,) (sensitivity - 100% and specificity - 97.1%, positive predictive value - 92.31%, negative predictive value - 100%, and Youden Index - 0.971), while that of RDW:TSC (AUROC: 1; P = 0.000) was 2.42 (sensitivity - 100%; specificity - 100%, positive predictive value - 100%, negative predictive value - 100%, and Youden Index - 1.00). Similarly, the cutoff value for RDW (AUROC: 0.947; P = 0.000) to predict mortality in AP was 17.20% (sensitivity - 100%; specificity - 87.4%, positive predictive value - 38.89%, negative predictive value - 100%, and Youden Index - 0.874) and that of RDW-to-TSC ratio (AUROC: 0.975; P = 0.000) was 2.9 (sensitivity - 100%; specificity - 96.6%, positive predictive value - 70%, negative predictive value - 100%, and Youden Index - 0.966). Conclusion: Our study found that RDW and RDW: TSC were quick, convenient, economic, sensitive, and dependable prognostic predictors of severity and mortality in patients with AP.

8.
Cell Rep ; 42(4): 112353, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37043353

RESUMO

Stem cell therapy shows promise for multiple disorders; however, the molecular crosstalk between grafted cells and host tissue is largely unknown. Here, we take a step toward addressing this question. Using translating ribosome affinity purification (TRAP) with sequencing tools, we simultaneously decode the transcriptomes of graft and host for human neural stem cells (hNSCs) transplanted into the stroke-injured rat brain. Employing pathway analysis tools, we investigate the interactions between the two transcriptomes to predict molecular pathways linking host and graft genes; as proof of concept, we predict host-secreted factors that signal to the graft and the downstream molecular cascades they trigger in the graft. We identify a potential host-graft crosstalk pathway where BMP6 from the stroke-injured brain induces graft secretion of noggin, a known brain repair factor. Decoding the molecular interplay between graft and host is a critical step toward deciphering the molecular mechanisms of stem cell action.


Assuntos
Células-Tronco Neurais , Acidente Vascular Cerebral , Ratos , Animais , Humanos , Encéfalo , Acidente Vascular Cerebral/terapia , Transplante de Células-Tronco , Diferenciação Celular
9.
Langmuir ; 39(1): 320-333, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36525568

RESUMO

Mechanical and solar to electrical energy conversion using piezo- and ferroelectric and photovoltaic effects may be a practical answer to the rising energy demand. In this quest, piezoelectric polymer poly(vinylidene fluoride-hexafluoroproylene) (P(VDF-HFP)) has gained interest due to its superior piezo- and ferroelectricity. In photovoltaic applications, inorganic halide perovskite (IHP) of CsPbI3 is considered a prime model compound. However, its application is limited because of the photoactive perovskite phase instability at ambient conditions. Here, we report the in situ synthesis of the stable perovskite γ-CsPbI3 through an electrospinning process at room temperature, encapsulated within a ferroelectric copolymer poly(vinylidene fluoride-hexafluoroproylene) (P(VDF-HFP)) as a composite nanofiber. Computational calculation using density functional theory (DFT) reveals that tensile strain plays a critical role in the dynamical stabilization of γ-CsPbI3. This tensile strain is triggered by the electrospinning process, which aids in the formation and growth of γ-CsPbI3. In the CsPbI3-P(VDF-HFP) composite nanofiber, γ-CsPbI3 nucleates the polar ß-crystalline phase in P(VDF-HFP), which results in the intrinsic piezo- and ferroelectric characteristics. The γ-CsPbI3 aids in preferable molecular dipole orientation, resulting in improved nanoscale piezo- and ferroelectric properties. The composite nanofiber features a higher piezoelectric d33 magnitude (∼30 pm/V) and lower decay constant for polarized domains (τcomposite ≈ 17). The composite was utilized as a piezoelectric nanogenerator to demonstrate human physiological motion monitoring in self-power mode. The relevant pressure sensitivities of 81 and 40 mV/kPa for the low-pressure (<0.6 kPa) and high-pressure (>0.6 to 12 kPa) ranges, respectively, promise its suitability in the health care sector.

10.
ACS Appl Mater Interfaces ; 15(21): 25110-25121, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35767722

RESUMO

Supramolecular assemblies with well-defined structural attenuation toward varied functional implications are an emerging area in mimicking natural biomaterials. In that regard, the redox stimuli-responsive ferrocene moiety can reversibly change between a nonpolar ferrocenyl and polar ferrocenium cation that endows interesting modular features to the building blocks with respect to self-assembly/disassembly. We design a series of ferrocene anchored peptide fragment NVFFAKKC using hydrophobic alkyl spacers of different chain lengths. Increasing the spacer length between the redox-responsive and self-assembling motifs increases the propensity to form robust nanofibers, which can be physically cross-linked to form hydrogels. The controlled redox response of the ferrocene moiety tandem with pH control provides access to structural control over the peptide nanostructures and tunable mechanical strengths. Further, such redox-sequestered dormant states hinder the spontaneous nucleation process that we exploit toward seeded supramolecular polymerization to form block cofibers composed of redox-responsive periphery and nonresponsive cores. Finally, such redox sequestration of peptide self-assembly renders an on-off piezoelectric response for potential utilization in peptide bioelectronics.


Assuntos
Nanofibras , Nanoestruturas , Metalocenos , Peptídeos/química , Nanoestruturas/química , Nanofibras/química
11.
Ann Plast Surg ; 90(4): 288-293, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29369102

RESUMO

BACKGROUND: Browlift is frequently combinedwith blepharoplasty; however, the literature is lacking on their combined effect on complication rates. OBJECTIVES: This study aims to evaluate major complication rates after blepharoplasty and brow lift and to determine if complication rates increase when blepharoplasty and brow lift were performed simultaneously. METHODS: A prospective cohort of patients who underwent cosmetic blepharoplasty, brow lift, or a combination of the 2 procedures between 2008 and 2013 was identified from the CosmetAssure Insurance database. The primary outcome was a postoperative major complication requiring emergency room evaluation, hospital admission, or reoperation within 30 days. Groups were compared with univariate analysis (significance, P < 0.05). RESULTS: A total of 6126 patients underwent aesthetic eye surgery, of which, 4879 (79.6%) underwent blepharoplasty, 441 (7.2%) brow lift, and 806 (13.2%) a combination the 2 procedures. Patients who underwent a combined procedure were older than patients who underwent isolated blepharoplasty or brow lift (55.5 ± 9.4 vs 54.6 ± 11.1 vs 53.3 ± 12.0 years; P < 0.01). In males, blepharoplasty was the most commonly performed procedure, followed by a combined procedure and brow lift (17.6% vs 12.9% vs 10.7%; P < 0.01). There were similar rates of smokers between the 3 groups (5.7% vs 8.0% vs 6.6%; P = 0.06). Between combined procedures, blepharoplasty, and brow lift there, were similar rates of major complications (0.4% vs 0.4% vs 0.7%; P = 0.65) and hematoma (0.2% vs 0.2% vs 0.5%; P = 0.49), which was the most common complication. CONCLUSIONS: Aesthetic eye surgery has a very low overall major complication rate (0.4%). When brow lift is combined with blepharoplasty, it poses no additional risk of major complications compared with either procedure alone.


Assuntos
Blefaroplastia , Ritidoplastia , Masculino , Humanos , Blefaroplastia/métodos , Estudos Prospectivos , Sobrancelhas , Ritidoplastia/métodos , Estética , Complicações Pós-Operatórias
12.
Curr Drug Targets ; 24(1): 55-70, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36173073

RESUMO

The objective of this paper is to look at how natural medicines can improve cognition and memory when used with sildenafil, a popular erectile dysfunction medicine that also has nootropic properties. Newer treatment strategies to treat the early stages of these diseases need to be developed. Multiple factors lead to complex pathophysiological conditions, which are responsible for various long-term complications. In this review, a combination of treatments targeting these pathologies is discussed. These combinations may help manage early and later phases of cognitive impairments. The purpose of this article is to discuss a link between these pathologies and a combinational approach with the objective of considering newer therapeutic strategies in the treatment of cognitive impairments. The natural drugs and their ingredients play a major role in the management of disease progression. Additionally, their combination with sildenafil allows for more efficacy and better response. Studies showing the effectiveness of natural drugs and sildenafil are mentioned, and how these combinations could be beneficial for the treatment of cognitive impairments and amnesia are summarised. Furthermore, preclinical and clinical trials are required to explore the medicinal potential of these drug combinations.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Masculino , Humanos , Citrato de Sildenafila/farmacologia , Citrato de Sildenafila/uso terapêutico , Disfunção Cognitiva/tratamento farmacológico , Cognição , Transtornos Cognitivos/tratamento farmacológico , Amnésia/psicologia
13.
PeerJ Comput Sci ; 8: e1184, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36532809

RESUMO

The modern competition is moving quickly toward incorporating cutting-edge technological improvements to support Small and Medium Enterprises (SMEs) in enhancing their business models. Making decisions regarding implementing new technologies in SMEs is a challenging process driven by the continuous new advances in the technology industry. Important operational process decisions, such as organizational investment costs, technology acquisition, maintenance, customer experience, employee training for the proper use of each technology, reliability requirements, and security needs, must be made very carefully for such adoptions. In this research, a novel multi-criteria decision-making process model is presented to help SME decision-makers choose the optimal technology from a list of desirable choices. The proposed approach makes use of a weighted multi-criteria decision model to rank parameters by combining many criteria that are crucial in choosing the best-suited technology. A literature review and expert opinion are utilized to pinpoint key decision-makers for the adoption of technological innovation. Specialists had reviewed the proposal in the field, and early findings suggest that it might be helpful to SME decision-makers in promoting customer value and firm performance.

14.
Cell Rep ; 41(11): 111825, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36516770

RESUMO

Hematopoietic stem and progenitor cells (HSPCs) sustain lifelong hematopoiesis. Mutations of pre-mRNA splicing machinery, especially splicing factor 3b, subunit 1 (SF3B1), are early lesions found in malignancies arising from HSPC dysfunction. However, why splicing factor deficits contribute to HSPC defects remains incompletely understood. Using zebrafish, we show that HSPC formation in sf3b1 homozygous mutants is dependent on STAT3 activation. Clinically, mutations in SF3B1 are heterozygous; thus, we explored if targeting STAT3 could be a vulnerability in these cells. We show that SF3B1 heterozygosity confers heightened sensitivity to STAT3 inhibition in zebrafish, mouse, and human HSPCs. Cells carrying mutations in other splicing factors or treated with splicing modulators are also more sensitive to STAT3 inhibition. Mechanistically, we illustrate that STAT3 inhibition exacerbates aberrant splicing in SF3B1 mutant cells. Our findings reveal a conserved vulnerability of splicing factor mutant HSPCs that could allow for their selective targeting in hematologic malignancies.


Assuntos
Hematopoese , Peixe-Zebra , Camundongos , Humanos , Animais , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Peixe-Zebra/metabolismo , Hematopoese/genética , Splicing de RNA/genética , Células-Tronco Hematopoéticas/metabolismo , Mutação/genética , Fosfoproteínas/metabolismo , Fator de Transcrição STAT3/genética
15.
Glob Chall ; 6(12): 2200099, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36532242

RESUMO

Li-ion battery (LIB) recycling has become an urgent need with rapid prospering of the electric vehicle (EV) industry, which has caused a shortage of material resources and led to an increasing amount of retired batteries. However, the global LIB recycling effort is hampered by various factors such as insufficient logistics, regulation, and technology readiness. Here, the challenges associated with LIB recycling and their possible solutions are summarized. Different aspects such as recycling/upcycling techniques, worldwide government policies, and the economic and environmental impacts are discussed, along with some practical suggestions to overcome these challenges for a promising circular economy for LIB materials. Some potential strategies are proposed to convert such challenges into opportunities to maintain the global expansion of the EV and other LIB-dependent industries.

16.
Langmuir ; 38(40): 12157-12172, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36154054

RESUMO

In recent years, lead-free perovskite materials are exponentially emerging in photovoltaic and optoelectronic applications due to their low toxicity and superior optical properties. On the other hand, the demand for flexible, wearable, and lightweight optoelectronic devices is significantly growing in sensor and actuator technologies. In this scenario, lead-free perovskite-based flexible piezoelectric polymer composites have sparked considerable attention in this field due to their excellent piezo-, pyro-, ferroelectric, and photovoltaic properties. Thus, in this work, a long-term stable lead-free Cs3Bi2I9-PVDF composite is introduced. The in situ growth of the Cs3Bi2I9 perovskite induces 92% yield of the electroactive phase in the PVDF matrix. The possible mechanism behind the electroactive ß-phase transformation is presented via interfacial interactions of PVDF moieties with the Cs3Bi2I9 (CBI) perovskite, which also give rise to long-term environmental stability. Next, a piezoelectric nanogenerator (PNG) has been fabricated with the Cs3Bi2I9-PVDF composite for mechanical energy harvesting, biophysiological motion monitoring, and voice recognitions that have potential utility in the health-care sector. Furthermore, a photodetector is developed to realize the piezo-phototronic effect. It exhibits a fast photoswitching behavior with rise and decay times of 141 and 278 ms, respectively. Thus, it is confirmed that the flexible Cs3Bi2I9-PVDF composite has shown tremendous potential to be used as an optical signal-modulated piezo-responsive wearable sensor.


Assuntos
Compostos de Cálcio , Polivinil , Polímeros de Fluorcarboneto , Hidrolases , Óxidos , Titânio
17.
Heliyon ; 8(8): e10248, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36042720

RESUMO

This paper presents a fuzzy inference method to investigate the impact of project-based assessment on the desirable outcomes by analyzing students creative and critical thinking, collaborative decision-making, and communication skills with realistic constraints and standards through theory and practical implementation in (a) course attainment and (b) on overall program attainment carried out in engineering discipline. This paper uses twelve specific parameters to capture program attainment parameters (PAPs). It proposes three main parameters to define various assessment system elements required for assessing course attainment parameters (CAPs), correlated with each other. To the best of the author's knowledge, to date, there is no defined mathematical tool to map CAPs to PAPs. Thus, this paper proposes assessment pedagogy to evaluate the PAPs corresponding to CAPs to handle the vague correlation mapping using fuzzy logic. The methodology and the preliminary results conducted for one year are promising, helping educators evaluate a candidate's performance individually or in a group on several assessment criteria, assisting in attaining the knowledge, values, attitude, deep learning, and skills needed for sustainable education development.

19.
Respir Med Case Rep ; 36: 101603, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242517

RESUMO

Spontaneous pneumothorax (SP) in women of reproductive age with causes such as thoracic endometriosis syndrome (TES) presents a diagnostic and therapeutic challenge. A 33-year-old women was treated conservatively with chest tube insertion for a first occurrence of a right-sided pneumothorax in September 2015. In January 2016, a right-sided video-assisted thoracoscopic surgery (VATS) wedge resection and partial parietal pleurectomy was performed due to a recurrence. A right-sided VATS was again performed in December 2016 with multiple wedge resections and a total pleurectomy revealing a pulmonary Langerhans' cell histiocytosis (PLCH) in the histological and immunohistochemical examinations. The patient was recommended an abstinence of smoking and further course was unremarkable until May 2019, when due to a recurrent pneumothorax, she received a talc pleurodesis via right-sided VATS. Due to yet another recurrence, she underwent a talc slurry pleurodesis over a right sided chest drain. In March 2020 due to recurrence, a right-sided VATS was performed and a blueish nodular lesion was resected from the diaphragm. The histological examination revealed an endometriosis with a diagnosis of TES. Since the patient did not exhibit a temporal relationship between her periods and the onset of pneumothorax symptoms, a final diagnosis of non-catamenial endometriosis-related pneumothorax was made. The patient is currently continuing smoking abstinence and is under hormone therapy. She has not presented with a recurrence. In clinical practice, it is important not to just relay on the information available to us, but to reevaluate the patient history to uncover new clues leading to a new diagnosis.

20.
Elife ; 112022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34984976

RESUMO

Protein arginine methyltransferases (PRMTs) are required for the regulation of RNA processing factors. Type I PRMT enzymes catalyze mono- and asymmetric dimethylation; Type II enzymes catalyze mono- and symmetric dimethylation. To understand the specific mechanisms of PRMT activity in splicing regulation, we inhibited Type I and II PRMTs and probed their transcriptomic consequences. Using the newly developed Splicing Kinetics and Transcript Elongation Rates by Sequencing (SKaTER-seq) method, analysis of co-transcriptional splicing demonstrated that PRMT inhibition resulted in altered splicing rates. Surprisingly, co-transcriptional splicing kinetics did not correlate with final changes in splicing of polyadenylated RNA. This was particularly true for retained introns (RI). By using actinomycin D to inhibit ongoing transcription, we determined that PRMTs post-transcriptionally regulate RI. Subsequent proteomic analysis of both PRMT-inhibited chromatin and chromatin-associated polyadenylated RNA identified altered binding of many proteins, including the Type I substrate, CHTOP, and the Type II substrate, SmB. Targeted mutagenesis of all methylarginine sites in SmD3, SmB, and SmD1 recapitulated splicing changes seen with Type II PRMT inhibition, without disrupting snRNP assembly. Similarly, mutagenesis of all methylarginine sites in CHTOP recapitulated the splicing changes seen with Type I PRMT inhibition. Examination of subcellular fractions further revealed that RI were enriched in the nucleoplasm and chromatin. Taken together, these data demonstrate that, through Sm and CHTOP arginine methylation, PRMTs regulate the post-transcriptional processing of nuclear, detained introns.


Assuntos
Regulação da Expressão Gênica , Íntrons/genética , Proteínas Nucleares/genética , Proteína-Arginina N-Metiltransferases/genética , Fatores de Transcrição/genética , Proteínas Centrais de snRNP/genética , Linhagem Celular , Humanos , Metilação , Proteínas Nucleares/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Centrais de snRNP/metabolismo
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