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1.
J Breast Imaging ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912622

RESUMO

BACKGROUND: High mammographic density increases breast cancer risk and reduces mammographic sensitivity. We reviewed evidence on accuracy of supplemental MRI for women with dense breasts at average or increased risk. METHODS: PubMed and Embase were searched 1995-2022. Articles were included if women received breast MRI following 2D or tomosynthesis mammography. Risk of bias was assessed using QUADAS-2. Analysis used independent studies from the articles. Fixed-effect meta-analytic summaries were estimated for predefined groups (PROSPERO: 230277). RESULTS: Eighteen primary research articles (24 studies) were identified in women aged 19-87 years. Breast density was heterogeneously or extremely dense (BI-RADS C/D) in 15/18 articles and extremely dense (BI-RADS D) in 3/18 articles. Twelve of 18 articles reported on increased-risk populations. Following 21 440 negative mammographic examinations, 288/320 cancers were detected by MRI. Substantial variation was observed between studies in MRI cancer detection rate, partly associated with prevalent vs incident MRI exams (prevalent: 16.6/1000 exams, 12 studies; incident: 6.8/1000 exams, 7 studies). MRI had high sensitivity for mammographically occult cancer (20 studies with at least 1-year follow-up). In 5/18 articles with sufficient data to estimate relative MRI detection rate, approximately 2 in 3 cancers were detected by MRI (66.3%, 95% CI, 56.3%-75.5%) but not mammography. Positive predictive value was higher for more recent studies. Risk of bias was low in most studies. CONCLUSION: Supplemental breast MRI following negative mammography in women with dense breasts has breast cancer detection rates of ~16.6/1000 at prevalent and ~6.8/1000 at incident MRI exams, considering both high and average risk settings.

2.
Nanotechnology ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941985

RESUMO

Memristors have recently received substantial attention because of its promising and unique application scenes emerging in neuromorphic computing which can achieve gains in computation speed by mimicking the topology of brains in electronic circuits. Traditional memristors made of bulk MoO3 and HfO2, etc. suffer from low switching ratio, short durability and poor stability. In this work, a floating-gate memristor is developed based on a mixed-dimensional heterostructure which is comprised of two-dimensional (2D) molybdenum disulfide (MoS2) and 0-dimensional (0D) Au nanoparticles (AuNPs) separated by an insulating hexagonal boron nitride (h-BN) layer, hereafter, MoS2/h-BN/AuNPs. We find that under the modulation of back-gate voltages, the MoS2/h-BN/AuNPs device operates reliably between a high resistance state (HRS) and a low resistance state (LRS) and that it shows multiple stable LRS states, demonstrating high potential of our memristor in application of multibit storage. The modulation effect can be attributed to the electron quantum tunneling between the AuNPs charge-trapping layer and MoS2 channel. Our memristor exhibits excellent durability and stability: the HRS and LRS remain more than 104 s without obvious degradation and the on/off ratio retains > 104 after more than 3000 switching cycles. We also demonstrate frequency-dependent memory properties upon electrical and optical pulse stimuli.

3.
Eur J Pharm Biopharm ; 201: 114348, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38844097

RESUMO

Nitric oxide (NO) / ß-Lapachone (Lap) combined therapy by causing oxidative stress is an effective tumor therapy strategy. Herein, a dual-responsive lipid nanoparticles (LNPs) LSNO for NO / Lap co-delivery were constructed from the zinc-coordinated lipid (DSNO(Zn)) and the hydrophobic drug Lap in the presence of helper lipids (DOPE and DSPE-PEG2000). The zinc-coordinated structure in LSNO might elevate the Zn2+ content in tumor cells, contributing to antioxidant imbalance. The fluorescent assays proved the light-triggered NO release and fluorescent self-reporting abilities of LSNO. In addition, the LNPs had good drug release behavior under high concentration of GSH, indicating the NO / drug co-delivery capacity. In vitro antitumor assays showed that the NO / Lap combination treatment group could induce more significant tumor cell growth inhibition and cell apoptosis than individual NO or Lap treatment. The following mechanism studies revealed that NO / Lap combination treatment led to distinct oxidative stress by producing reactive oxygen species (ROS) and peroxynitrite anion (ONOO-). On the other hand, the intracellular redox balance could be further disrupted by Lap-induced NADPH consumption and Zn2+ / NO-induced reductase activities downregulation, thus promoting the degree of cell damage. Besides, it was also found that NO and Lap could directly damage nuclear DNA and induce mitochondrial dysfunction, thereby leading to caspase-3 activation and tumor cell death. These results proved that LSNO could serve as a promising multifunctional tumor therapy platform.


Assuntos
Nanopartículas , Naftoquinonas , Óxido Nítrico , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio , Naftoquinonas/administração & dosagem , Naftoquinonas/farmacologia , Naftoquinonas/química , Óxido Nítrico/metabolismo , Óxido Nítrico/administração & dosagem , Humanos , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Zinco/química , Zinco/administração & dosagem , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Lipídeos/química , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia
4.
Photodiagnosis Photodyn Ther ; 48: 104237, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38871017

RESUMO

PURPOSE: To report the use of anterior segment optical coherence tomography (AS-OCT) for superficial keratectomy (SK) in anterior corneal opacity. METHODS: The characteristics of 43 eyes (39 patients) with various lesions responsible for anterior corneal opacity were included in this retrospective non-comparative study. AS-OCT was performed on all eyes before surgery. The thickness of corneal opacity and the underlying healthy stroma were measured. SK was performed on each individual. RESULTS: Four types of anterior corneal opacity were evaluated, including corneal degeneration (26/43), Reis-Bücklers corneal dystrophy (8/43), alkali burn (1/43) and corneal tumors (8/43). Based on AS-OCT images, all eyes showed abnormal hyper-reflective signals in the superficial cornea to less than one-third of the normal corneal thickness in the deepest corneal opacity. All 43 eyes underwent an SK procedure. In addition, 1 eye with alkali burns and 7 eyes with corneal tumors were combined with amniotic membrane transplantation. All eyes restored transparency without significant complications. CONCLUSION: AS-OCT is a valuable method for objective preoperative and noninvasive assessments of anterior corneal opacities and is useful for guiding SK.

5.
J Ethnopharmacol ; 333: 118497, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942156

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The traditional medicinal formulation, Qifu-yin (QFY), has been widely prescribed for Alzheimer's disease (AD) treatment in China, yet the comprehensive mechanisms through which QFY mitigates AD pathology remain to be fully delineated. AIM OF THE STUDY: This study aimed to explore the therapeutic implications of QFY on the synaptic injury and oxidative stress in the hippocampus of APPswe/PS1dE9 (APP/PS1) mice, with a concerted effort to elucidate the molecular mechanisms related to synaptic preservation and memory improvement. MATERIALS AND METHODS: The components of QFY were identified by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The neuroprotective effects of QFY was evaluated using six-month-old male APP/PS1 mice. Subsequent to a 15 days of QFY regimen, spatial memory was assessed utilizing the Morris water maze (MWM) test. Amyloid-beta (Aß) aggregation was detected via immunostaining, while the quantification of Aß1-40 and Aß1-42 was achieved through enzyme-linked immunosorbent assay (ELISA). Transmission electron microscopy (TEM) was used to investigate the synaptic structure and mitochondrial morphology. Golgi staining was applied to examine dendritic spine density. Reactive oxygen species (ROS), 3-nitrotyrosine (3-NT) and 4-hydroxy-nonenal (4-HNE) assays were employed to assess oxidative stress. The expression profiles of Aß metabolism-associated enzymes and the Keap1/Nrf2/ARE signaling pathway were determined by Western blot. RESULTS: A total of 20 principal compounds in QFY were identified. QFY mitigated memory deficits of APP/PS1 mice, including reducing escape latency and search distance and increasing the time and distance spent in the target quadrant. In addition, QFY increased platform crossings of APP/PS1 mice in the probe trial of MWM tests. TEM analysis showed that QFY increased synapse number in the CA1 region of APP/PS1 mice. Further studies indicated that QFY elevated the expression levels of Post synaptic density protein 95 (PSD95) and synaptophysin, and mitigated the loss of dendritic spine density in the hippocampus of APP/PS1 mice. QFY has been shown to ameliorated the structural abnormalities of mitochondria, including mitochondrial dissolution and degradation, up-regulate ATP synthesis and membrane potential in the hippocampus of APP/PS1 mice. Moreover, QFY activated the Keap1/Nrf2/ARE signaling pathway in the hippocampus of APP/PS1 mice, which might contribute to the neuroprotective effects of QFY. CONCLUSION: QFY activates the Keap1/Nrf2/ARE signaling, and protects against synaptic and mitochondrial dysfunction in APP/PS1 mice, proposing a potential alternative therapeutic strategy for AD management.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Precursor de Proteína beta-Amiloide , Medicamentos de Ervas Chinesas , Proteína 1 Associada a ECH Semelhante a Kelch , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2 , Fármacos Neuroprotetores , Estresse Oxidativo , Transdução de Sinais , Animais , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Masculino , Transdução de Sinais/efeitos dos fármacos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Camundongos , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Fármacos Neuroprotetores/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Presenilina-1/genética , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Elementos de Resposta Antioxidante/efeitos dos fármacos , Modelos Animais de Doenças
6.
FASEB J ; 38(10): e23705, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38805171

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with a notoriously dismal prognosis. As a competitive inhibitor of DNA synthesis, gemcitabine is the cornerstone drug for treating PDAC at all stages. The therapeutic effect of gemcitabine, however, is often hindered by drug resistance, and the underlying mechanisms remain largely unknown. It is unclear whether their response to chemotherapeutics is regulated by endocrine regulators, despite the association between PDAC risk and endocrine deregulation. Here, we show that prolactin receptor (PRLR) synergizes with gemcitabine in both in vitro and in vivo treatment of PDAC. Interestingly, PRLR promotes the expression of miR-4763-3p and miR-3663-5p, two novel miRNAs whose functions are unknown. Furthermore, the analysis of transcriptome sequencing data of tumors from lactating mouse models enriches the PPP pathway, a multifunctional metabolic pathway. In addition to providing energy, the PPP pathway mainly provides a variety of raw materials for anabolism. We demonstrate that two key enzymes of the pentose phosphate pathway (PPP), G6PD and TKT, are directly targeted by miR-4763-3p and miR-3663-5p. Notably, miR-4763-3p and miR-3663-5p diminish the nucleotide synthesis of the PPP pathway, thereby increasing gemcitabine sensitivity. As a result, PRLR harnesses these two miRNAs to suppress PPP and nucleotide synthesis, subsequently elevating the gemcitabine sensitivity of PDAC cells. Also, PDAC tissues and tumors from LSL-KrasG12D/+, LSL-Trp53R172H/+, and PDX1-cre (KPC) mice exhibit downregulation of PRLR. Bisulfite sequencing of PDAC tissues revealed that PRLR downregulation is due to epigenetic methylation. In this study, we show for the first time that the endocrine receptor PRLR improves the effects of gemcitabine by boosting two new miRNAs that block the PPP pathway and nucleotide synthesis by inhibiting two essential enzymes concurrently. The PRLR-miRNAs-PPP axis may serve as a possible therapeutic target to supplement chemotherapy advantages in PDAC.


Assuntos
Carcinoma Ductal Pancreático , Desoxicitidina , Gencitabina , Glucosefosfato Desidrogenase , MicroRNAs , Neoplasias Pancreáticas , Receptores da Prolactina , Animais , Feminino , Humanos , Camundongos , Antimetabólitos Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucosefosfato Desidrogenase/metabolismo , Glucosefosfato Desidrogenase/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Receptores da Prolactina/metabolismo , Receptores da Prolactina/genética , Camundongos Nus
7.
Cancer Immunol Immunother ; 73(6): 115, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38693304

RESUMO

In the malignant progression of tumors, there is deposition and cross-linking of collagen, as well as an increase in hyaluronic acid content, which can lead to an increase in extracellular matrix stiffness. Recent research evidence have shown that the extracellular matrix plays an important role in angiogenesis, cell proliferation, migration, immunosuppression, apoptosis, metabolism, and resistance to chemotherapeutic by the alterations toward both secretion and degradation. The clinical importance of tumor-associated macrophage is increasingly recognized, and macrophage polarization plays a central role in a series of tumor immune processes through internal signal cascade, thus regulating tumor progression. Immunotherapy has gradually become a reliable potential treatment strategy for conventional chemotherapy resistance and advanced cancer patients, but the presence of immune exclusion has become a major obstacle to treatment effectiveness, and the reasons for their resistance to these approaches remain uncertain. Currently, there is a lack of exact mechanism on the regulation of extracellular matrix stiffness and tumor-associated macrophage polarization on immune exclusion. An in-depth understanding of the relationship between extracellular matrix stiffness, tumor-associated macrophage polarization, and immune exclusion will help reveal new therapeutic targets and guide the development of clinical treatment methods for advanced cancer patients. This review summarized the different pathways and potential molecular mechanisms of extracellular matrix stiffness and tumor-associated macrophage polarization involved in immune exclusion and provided available strategies to address immune exclusion.


Assuntos
Matriz Extracelular , Neoplasias , Macrófagos Associados a Tumor , Humanos , Matriz Extracelular/metabolismo , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/metabolismo , Neoplasias/terapia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Animais , Microambiente Tumoral/imunologia , Imunoterapia/métodos , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo
8.
Healthcare (Basel) ; 12(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38610227

RESUMO

Despite curative treatment and discharge from acute hospital settings, breast cancer patients often have cancer- and treatment-related morbidity which impairs them from returning to work. Hence, the role of community-based return to work rehabilitation programs is important to help these patients transition back to work. This was a retrospective cohort study involving patients with breast cancer conducted at a community-based cancer rehabilitation center. Patients were involved in an interdisciplinary vocational rehabilitation program involving physiatrists, occupational therapists, physiotherapists and social workers. We recruited 63 patients for this study cohort, with 46 (73.0%) patients ≤ 60 years old. After undergoing the rehabilitation program, there were 37 (58.7%) participants who successfully returned to work. These participants returned to work at either within 6 months (27.0%), 12 months (29.7%) or 24 months (43.2%) after enrollment into the program, with a majority enrolling in white collar jobs. Multivariate regression analysis revealed that significant negative factors for return to work were advanced stage of cancer (p = 0.004), along with clinically significant fatigue, measured on the Brief Fatigue Inventory (p < 0.001). However, perceived work ability (p = 0.020) was found to be a positive factor.

9.
Eur Respir J ; 63(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38636970

RESUMO

BACKGROUND: Up to 50% of those attending for low-dose computed tomography screening for lung cancer continue to smoke and co-delivery of smoking cessation services alongside screening may maximise clinical benefit. Here we present data from an opt-out co-located smoking cessation service delivered alongside the Yorkshire Lung Screening Trial (YLST). METHODS: Eligible YLST participants were offered an immediate consultation with a smoking cessation practitioner (SCP) at their screening visit with ongoing smoking cessation support over subsequent weeks. RESULTS: Of 2150 eligible participants, 1905 (89%) accepted the offer of an SCP consultation during their initial visit, with 1609 (75%) receiving ongoing smoking cessation support over subsequent weeks. Uptake of ongoing support was not associated with age, ethnicity, deprivation or educational level in multivariable analyses, although men were less likely to engage (adjusted OR (ORadj) 0.71, 95% CI 0.56-0.89). Uptake was higher in those with higher nicotine dependency, motivation to stop smoking and self-efficacy for quitting. Overall, 323 participants self-reported quitting at 4 weeks (15.0% of the eligible population); 266 were validated by exhaled carbon monoxide (12.4%). Multivariable analyses of eligible smokers suggested 4-week quitting was more likely in men (ORadj 1.43, 95% CI 1.11-1.84), those with higher motivation to quit and previous quit attempts, while those with a stronger smoking habit in terms of cigarettes per day were less likely to quit. CONCLUSIONS: There was high uptake for co-located opt-out smoking cessation support across a wide range of participant demographics. Protected funding for integrated smoking cessation services should be considered to maximise programme equity and benefit.


Assuntos
Abandono do Hábito de Fumar , Tabagismo , Masculino , Humanos , Abandono do Hábito de Fumar/métodos , Serviços de Saúde Comunitária , Pulmão , Tomografia
10.
World J Surg ; 48(1): 48-58, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38686802

RESUMO

BACKGROUND: Major abdominal surgery is associated with a high rate of post-operative complications with increased risk of adverse surgical outcomes due to the presence of frailty. This study aims to evaluate the effectiveness of the multimodal Recovery of Surgery in the Elderly (ROSE) prehabilitation program with supervised exercise in mitigating postoperative functional decline when compared to standard care. METHOD: The ROSE program enrolled ambulant patients who were 65 years and above, had a Clinical Frailty Scale score of 4 or more and were planned for major abdominal surgery. Participation in supervised exercise sessions before surgery were compared with standard physiotherapy advice. The primary outcome was 6-min walk test (6MWT) distance assessed at baseline, after prehabilitation and 30 days follow-up after surgery. Secondary outcomes included physical performance, length of hospital stay and postoperative morbidity. RESULTS: Data from 74 eligible patients, 37 in each group, were included. Median age was 78 years old. Forty-two patients (22 in Prehab group and 20 in control group) with complete 6MWT follow-up data at 30 days follow-up were analysed for outcomes. Most patients underwent laparoscopic surgery (63.5%) and almost all of the surgeries were for abdominal malignancies (97.3%). The Prehab group had an increase in 6MWT distance at the 30-day follow up, from a baseline mean (SD) of 277.4 (125) m to 287.6 (143.5) m (p = 0.415). The 6MWT distance in the control group decreased from a baseline mean (SD) of 281.7 (100.5) m to 260.1 (78.6) m at the 30-day follow up (p = 0.086). After adjusting for baseline 6MWT distance and frailty score, the Prehab group had significantly higher 6MWT distance at 30-day follow-up than control (difference in adjusted means 41.7 m, 95% confidence interval 8.7-74.8 m, p = 0.015). There were no significant between-group differences in the secondary outcomes. CONCLUSION: A multimodal prehabilitation program with supervised exercise within a short time frame can improve preoperative functional capacity and maintain baseline functional capacity in frail older adults undergoing major abdominal surgery.


Assuntos
Complicações Pós-Operatórias , Exercício Pré-Operatório , Humanos , Idoso , Feminino , Masculino , Idoso de 80 Anos ou mais , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Idoso Fragilizado , Abdome/cirurgia , Resultado do Tratamento , Recuperação de Função Fisiológica , Terapia por Exercício/métodos , Fragilidade , Estudos Prospectivos
12.
Acta Pharmacol Sin ; 45(6): 1160-1174, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38438581

RESUMO

Nicotinic acetylcholine receptors (nAChRs) regulate pain pathways with various outcomes depending on receptor subtypes, neuron types, and locations. But it remains unknown whether α4ß2 nAChRs abundantly expressed in the substantia nigra pars reticulata (SNr) have potential to mitigate hyperalgesia in pain states. We observed that injection of nAChR antagonists into the SNr reduced pain thresholds in naïve mice, whereas injection of nAChR agonists into the SNr relieved hyperalgesia in mice, subjected to capsaicin injection into the lower hind leg, spinal nerve injury, chronic constriction injury, or chronic nicotine exposure. The analgesic effects of nAChR agonists were mimicked by optogenetic stimulation of cholinergic inputs from the pedunculopontine nucleus (PPN) to the SNr, but attenuated upon downregulation of α4 nAChRs on SNr GABAergic neurons and injection of dihydro-ß-erythroidine into the SNr. Chronic nicotine-induced hyperalgesia depended on α4 nAChRs in SNr GABAergic neurons and was associated with the reduction of ACh release in the SNr. Either activation of α4 nAChRs in the SNr or optogenetic stimulation of the PPN-SNr cholinergic projection mitigated chronic nicotine-induced hyperalgesia. Interestingly, mechanical stimulation-induced ACh release was significantly attenuated in mice subjected to either capsaicin injection into the lower hind leg or SNI. These results suggest that α4 nAChRs on GABAergic neurons mediate a cholinergic analgesic circuit in the SNr, and these receptors may be effective therapeutic targets to relieve hyperalgesia in acute and chronic pain, and chronic nicotine exposure.


Assuntos
Neurônios GABAérgicos , Hiperalgesia , Camundongos Endogâmicos C57BL , Receptores Nicotínicos , Animais , Receptores Nicotínicos/metabolismo , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/fisiologia , Masculino , Hiperalgesia/metabolismo , Hiperalgesia/tratamento farmacológico , Camundongos , Parte Reticular da Substância Negra/metabolismo , Parte Reticular da Substância Negra/efeitos dos fármacos , Nicotina/farmacologia , Analgésicos/farmacologia , Agonistas Nicotínicos/farmacologia , Antagonistas Nicotínicos/farmacologia , Capsaicina/farmacologia , Acetilcolina/metabolismo , Optogenética , Limiar da Dor/efeitos dos fármacos
13.
Molecules ; 29(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38542881

RESUMO

RNAs play crucial roles in various essential biological functions, including catalysis and gene regulation. Despite the widespread use of coarse-grained (CG) models/simulations to study RNA 3D structures and dynamics, their direct application is challenging due to the lack of atomic detail. Therefore, the reconstruction of full atomic structures is desirable. In this study, we introduced a straightforward method called ABC2A for reconstructing all-atom structures from RNA CG models. ABC2A utilizes diverse nucleotide fragments from known structures to assemble full atomic structures based on the CG atoms. The diversification of assembly fragments beyond standard A-form ones, commonly used in other programs, combined with a highly simplified structure refinement process, ensures that ABC2A achieves both high accuracy and rapid speed. Tests on a recent large dataset of 361 RNA experimental structures (30-692 nt) indicate that ABC2A can reconstruct full atomic structures from three-bead CG models with a mean RMSD of ~0.34 Å from experimental structures and an average runtime of ~0.5 s (maximum runtime < 2.5 s). Compared to the state-of-the-art Arena, ABC2A achieves a ~25% improvement in accuracy and is five times faster in speed.


Assuntos
Simulação de Dinâmica Molecular , RNA , RNA/química , Nucleotídeos
14.
Oncogenesis ; 13(1): 10, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424455

RESUMO

Endocrine receptors play an essential role in tumor metabolic reprogramming and represent a promising therapeutic avenue in pancreatic ductal adenocarcinoma (PDAC). PDAC is characterized by a nutrient-deprived microenvironment. To meet their ascendant energy demands, cancer cells can internalize extracellular proteins via macropinocytosis. However, the roles of endocrine receptors in macropinocytosis are not clear. In this study, we found that progesterone receptor (PGR), a steroid-responsive nuclear receptor, is highly expressed in PDAC tissues obtained from both patients and transgenic LSL-KrasG12D/+; LSL-Trp53R172H/+; PDX1-cre (KPC) mice. Moreover, PGR knockdown restrained PDAC cell survival and tumor growth both in vitro and in vivo. Genetic and pharmacological PGR inhibition resulted in a marked attenuation of macropinocytosis in PDAC cells and subcutaneous tumor models, indicating the involvement of this receptor in macropinocytosis regulation. Mechanistically, PGR upregulated CDC42, a critical regulator in macropinocytosis, through PGR-mediated transcriptional activation. These data deepen the understanding of how the endocrine system influences tumor progression via a non-classical pathway and provide a novel therapeutic option for patients with PDAC.

15.
Research (Wash D C) ; 7: 0300, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38314086

RESUMO

Ferroptosis, a nonapoptotic form of cell death, is an emerging potential therapeutic target for various diseases, including cancer. However, the role of ferroptosis in pancreatic cancer remains poorly understood. Pancreatic ductal adenocarcinoma (PDAC) is characterized by a poor prognosis and chemotherapy resistance, attributed to its high Kirsten rats arcomaviral oncogene homolog mutation rate and severe nutritional deficits resulting from a dense stroma. Several studies have linked rat sarcoma (RAS) mutations to ferroptosis, suggesting that inducing ferroptosis may be an effective strategy against oncogenic RAS-bearing tumors. We investigated the role of Family With Sequence Similarity 60 Member A (FAM60A) in this study, a protein closely associated with a poor prognosis and highly expressed in PDAC and tumor tissue from KrasG12D/+;Trp53R172H/+; Pdx1-Cre mice, in regulating ferroptosis, tumor growth, and gemcitabine sensitivity in vitro and in vivo. Our results demonstrate that FAM60A regulates 3 essential metabolic enzymes, ACSL1/4 and GPX4, to protect PDAC cells from ferroptosis. Furthermore, we found that YY1 transcriptionally regulates FAM60A expression by promoting its transcription, and the Hippo-YY1 pathway is restricted in the low-amino-acid milieu in the context of nutrient deprivation, leading to downstream suppression of peroxisome proliferator-activated receptor and ACSL1/4 and activation of GPX4 pathways. Importantly, FAM60A knockdown sensitized PDAC cells to gemcitabine treatment. A new understanding of FAM60A transcriptional regulation pattern in PDAC and its dual function in ferroptosis reliever and chemotherapy resistance is provided by our study. Targeting FAM60A may therefore offer a promising therapeutic approach for PDAC by simultaneously addressing 2 major features of the disease (high RAS mutation rate and tumor microenvironment nutrient deficiency) and preventing tumor cell metabolic adaptation.

16.
Med Chem ; 20(4): 422-433, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38351695

RESUMO

OBJECTIVE: This study aimed to overcome the growing antibiotic resistance. Moreover, the new series of emodin alkyl azoles were synthesized. METHOD: The novel emodin alkyl azoles were synthesized using commercial emodin and azoles by alkylation. The NMR and HRMS spectra were employed to confirm the structures of novel prepared compounds. The in vitro antibacterial and antifungal activities of the prepared emodin compounds were studied by the 96-well plate method. The binding behavior between emodin 4-nitro imidazole compound 3c and S. aureus DNA was researched using an ultraviolet-visible spectrophotometer. Furthermore, fluorescence spectrometry was used to explore the interaction with human serum albumin (HSA). RESULTS: The in vitro antimicrobial results displayed that compound 3c gave relatively strong activities with MIC values of 4-16 µg/mL. Notably, this compound exhibited 2-fold more potent activity against S. aureus (MIC = 4 µg/mL) and E. coli (MIC = 8 µg/mL) strains than clinical drug Chloromycin (MIC = 8 and 16 µg/mL). The UV-vis absorption spectroscopy showed that 4-nitro imidazole emodin 3c could form the 3c-DNA complex by intercalating into S. aureus DNA, inhibiting antimicrobial activities. The simulation results displayed that the emodin 3c and DNA complex were formed by hydrogen bonds. The spectral experiment demonstrated that compound 3c could be transported by human serum albumin (HSA) via hydrogen bonds. The molecular simulation found that the hydroxyl group and the nitroimidazole ring of the emodin compound showed an important role in transportation behavior. CONCLUSION: This work may supply useful directions for the exploration of novel antimicrobial agents.


Assuntos
Azóis , Emodina , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Albumina Sérica Humana , Staphylococcus aureus , Emodina/farmacologia , Emodina/química , Emodina/síntese química , Emodina/análogos & derivados , Humanos , Albumina Sérica Humana/química , Albumina Sérica Humana/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Azóis/química , Azóis/farmacologia , Azóis/síntese química , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Antifúngicos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , DNA/metabolismo , DNA/química , Relação Estrutura-Atividade , Estrutura Molecular , DNA Bacteriano/efeitos dos fármacos , DNA Bacteriano/metabolismo
17.
ERJ Open Res ; 10(1)2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38410702

RESUMO

Chronic Pseudomonas aeruginosa (PA) infection significantly contributes to morbidity and mortality in bronchiectasis patients. Initiating antibiotics early may lead to the eradication of PA. Here we outline the design of a trial (ERASE; NCT06093191) assessing the efficacy and safety of inhaled tobramycin, alone or with oral ciprofloxacin, in bronchiectasis patients with a new isolation of PA. This multicentre, 2×2 factorial randomised, double-blind, placebo-controlled, parallel-group trial includes a 2-week screening period, a 12-week treatment phase (with a combination of ciprofloxacin or a placebo at initial 2 weeks) and a 24-week follow-up. 364 adults with bronchiectasis and a new PA isolation will be randomly assigned to one of four groups: placebo (inhaled saline and ciprofloxacin placebo twice daily), ciprofloxacin alone (750 mg ciprofloxacin and inhaled saline twice daily), inhaled tobramycin alone (inhaled 300 mg tobramycin and ciprofloxacin placebo twice daily) or a combination of both drugs (inhaled 300 mg tobramycin and 750 mg ciprofloxacin twice daily). The primary objective of this study is to assess the proportion of patients successfully eradicating PA in each group by the end of the study. Efficacy will be evaluated based on the eradication rate of PA at other time points (12, 24 and 36 weeks), the occurrence of exacerbations and hospitalisations, time to first pulmonary exacerbations, patient-reported outcomes, symptom measures, pulmonary function tests and the cost of hospitalisations. To date no randomised trial has evaluated the benefit of different PA eradication strategies in bronchiectasis patients. The ERASE trial will therefore generate crucial data to inform future clinical guidelines.

18.
Bioorg Med Chem ; 100: 117635, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38340641

RESUMO

Although many types of cationic lipids have been developed as efficient gene vectors, the construction of lipid molecules with simple procedures remains challenging. Passerini reaction, as a classic multicomponent reaction, could directly give the α-acyloxycarboxamide products with biodegradable ester and amide bonds. Herein, two series of novel cationic lipids with heterocyclic pyrrolidine and piperidine as headgroups were synthesized through Passerini reaction (P-series) and amide condensation (A-series), and relevant structure-activity relationships on their gene delivery capability was studied. It was found that although both of the two series of lipids could form lipid nanoparticles (LNPs) which could effectively condense DNA, the LNP derived from P-series lipids showed higher transfection efficiency, serum tolerance, cellular uptake, and lower cytotoxicity. Unlike the A-series LNPs, the P-series LNPs showed quite different structure-activity relationship, in which the relative site of the secondary amine had significant effect on the transfection performance. The othro-isomers of the P-series lipids had lower cytotoxicity, but poor transfection efficiency, which was probably due to their unstable nature. Taken together, this study not only validated the feasibility of Passerini reaction for the construction of cationic lipids for gene delivery, but also afforded some clues for the rational design of effective non-viral lipidic gene vectors.


Assuntos
Técnicas de Transferência de Genes , Lipídeos , Humanos , Lipídeos/farmacologia , Lipídeos/química , Relação Estrutura-Atividade , Transfecção , Cátions/química , Amidas
19.
Br J Radiol ; 97(1154): 469-476, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308037

RESUMO

OBJECTIVES: To evaluate radiation doses for all low-dose CT scans performed during the first year of a lung screening trial. METHODS: For all lung screening scans that were performed using a CT protocol that delivered image quality meeting the RSNA QIBA criteria, radiation dose metrics, participant height, weight, gender, and age were recorded. Values of volume CT dose index (CTDIvol) and dose length product (DLP) were evaluated as a function of weight in order to assess the performance of the scan protocol across the participant cohort. Calculated effective doses were used to establish the additional lifetime attributable cancer risks arising from trial scans. RESULTS: Median values of CTDIvol, DLP, and effective dose (IQR) from the 3521 scans were 1.1 mGy (0.70), 42.4 mGycm (24.9), and 1.15 mSv (0.67), whilst for 60-80kg participants the values were 1.0 mGy (0.30), 35.8 mGycm (11.4), and 0.97 mSv (0.31). A statistically significant correlation between CTDIvol and weight was identified for males (r = 0.9123, P < .001) and females (r = 0.9052, P < .001), however, the effect of gender on CTDIvol was not statistically significant (P = .2328) despite notable differences existing at the extremes of the weight range. The additional lifetime attributable cancer risks from a single scan were in the range 0.001%-0.006%. CONCLUSIONS: Low radiation doses can be achieved across a typical lung screening cohort using scan protocols that have been shown to deliver high levels of image quality. The observed dose levels may be considered as typical values for lung screening scans on similar types of scanners for an equivalent participant cohort. ADVANCES IN KNOWLEDGE: Presentation of typical radiation dose levels for CT lung screening examinations in a large UK trial. Effective radiation doses can be of the order of 1 mSv for standard sized participants. Lifetime attributable cancer risks resulting from a single low-dose CT scan did not exceed 0.006%.


Assuntos
Neoplasias Pulmonares , Pulmão , Feminino , Humanos , Masculino , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Doses de Radiação , Tórax , Tomografia Computadorizada por Raios X/métodos , Ensaios Clínicos como Assunto
20.
Artigo em Inglês | MEDLINE | ID: mdl-38391023

RESUMO

OBJECTIVE: Immune-mediated necrotizing myopathy (IMNM) is pathologically characterized by diffuse myofiber necrosis and regeneration, myophagocytosis, and a sparse inflammatory infiltrate. The monocyte chemoattractant protein-1 (MCP-1) is a key chemokine that regulates monocyte/macrophage infiltration into injured tissues. The interleukin-6 (IL-6) signalling in the induction of MCP-1 expression has not been investigated in IMNM. METHODS: MCP-1 expression in muscle specimens was assessed using immunohistochemistry and real-time quantitative polymerase chain reaction (RT-qPCR). Levels of multiple serological cytokines were evaluated using the Meso Scale Discovery electrochemiluminescence system. Flow cytometry, RT-qPCR, enzyme-linked immunosorbent assay, western blot, dual-luciferase reporter assays, and chromatin immunoprecipitation-qPCR were performed to explore the effects of IL-6 signalling on MCP-1 production in human myoblasts. RESULTS: MCP-1 was scattered and was positively expressed within myofibers and a few inflammatory cells in the muscles of patients with IMNM. Sarcoplasmic MCP-1 expression significantly correlated with myonecrosis, myoregeneration, and inflammatory infiltration. Serum MCP-1, IL-6, and the soluble form of the IL-6 receptor (sIL-6R) were elevated in patients with IMNM compared with controls. Serological MCP-1 levels were significantly associated with serum IL-6 expression and clinical disease severity in IMNM patients. The IL-6/sIL-6R complex induced MCP-1 expression via the signal transducer and activator of transcription 3 (STAT3) pathway in human myoblasts. Mechanistically, phospho-STAT3 was enriched in the MCP-1 promoter region and promoted the transcription. CONCLUSION: IL-6 trans-signalling may contribute to the immunopathogenesis of IMNM by augmenting inflammation through regulation of MCP-1 expression in IMNM.

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