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2.
Ultrasonics ; 145: 107464, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39278053

RESUMO

Ultrasound imaging using an active sensing array has been extensively studied in both time domain and frequency domain. Subspace decomposition methods in match field beamforming such as the multiple signal classification (MUSIC) algorithm can achieve subwavelength resolution of distinct point scatterers. However, when the size of the target is on the order of one wavelength or larger, the MUSIC type algorithms suffer from poor performance due to a tangled eigen structure. This paper proposes an adaptive match field beamformer that does not require subspace decomposition to achieve high resolution imaging of extended targets. Specifically, the broadband coherent white noise constraint (C-WNC) algorithm is utilized to achieve high focusing ability of extended targets by exploiting the cross-frequency coherence in an active sensing scheme. The dynamic range bias in the adaptive beamformer benefits the C-WNC algorithm to achieve high contrast regardless of the SNR. Both simulations and experiments show that the C-WNC images retain their resolution cells on the tips of the extended target with sizes ranging from a wavelength to sizes as large as the physical aperture width. A robust imaging scheme is then proposed to obtain high quality images by combining C-WNC images with a statistically stable delay-multiply-and-sum (DMAS) algorithm to create high-contrast and high-resolution images of extended targets in both azimuth and axial range directions.

3.
Clin Transl Oncol ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39133386

RESUMO

PPM1F has been shown to play diverse biological functions in the progression of multiple tumors. PPM1F controls the T788/T789 phosphorylation switch of ITGB1 and regulates integrin activity. However, the impacts of PPM1F and ITGB1 on ovarian cancer (OV) progression remain unclear. Whether there is such a regulatory relationship between PPM1F and ITGB1 in ovarian cancer has not been studied. Therefore, the purpose of this study is to elucidate the function and the mechanism of PPM1F in ovarian cancer. The expression level and the survival curve of PPM1F were analyzed by databases. Gain of function and loss of function were applied to explore the function of PPM1F in ovarian cancer. A tumor formation assay in nude mice showed that knockdown of PPM1F inhibited tumor formation. We tested the effect of PPM1F on ITGB1 dephosphorylation in ovarian cancer cells by co-immunoprecipitation and western blotting. Loss of function was applied to investigate the function of ITGB1 in ovarian cancer. ITGB1-mut overexpression promotes the progression of ovarian cancer. Rescue assays showed the promoting effect of ITGB1-wt on ovarian cancer is attenuated due to the dephosphorylation of ITGB1-wt by PPM1F. PPM1F and ITGB1 play an oncogene function in ovarian cancer. PPM1F regulates the phosphorylation of ITGB1, which affects the occurrence and development of ovarian cancer.

4.
Ann Med ; 56(1): 2392882, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39155852

RESUMO

BACKGROUND: Systemic lupus erythematosus (SLE), an extensive autoimmune disorder, compromises viral resistance and alters immune responses post respiratory virus vaccines. This study aims to assess immune response levels and safety in SLE patients following respiratory virus vaccines. METHODS: Extensive searches, until 1 March 2024, were conducted using PubMed, EMBASE, and Cochrane Library. Outcomes, encompassing seroconversion rate (SCR), antibody and IgG titers, neutralizing antibodies, anti-spike antibodies, anti-receptor binding domain (RBD) IgG, and adverse events, were appraised. RESULTS: Sixteen articles, comprising 25 observational studies, were included. SLE patients exhibited lower SCR (OR = 0.42, 95%CI: 0.26 to 0.69), antibody titers (SMD=-2.84, 95%CI: -3.36 to -1.61), and neutralizing antibodies (OR = 0.27, 95%CI: 0.13 to 0.56) compared to the healthy population post respiratory virus vaccines. Notably, differences were statistically insignificant for anti-RBD IgG (OR = 1.75, 95%CI: 0.10 to 29.42), IgG titers (SMD=-2.54, 95%CI: -5.57 to -0.49), anti-spike antibodies (OR = 0.35, 95%CI: 0.08 to 1.53), injection site discomfort (OR = 1.03, 95%CI: 0.52 to 2.06), fatigue (OR = 1.23, 95%CI: 0.74 to 2.03), fever (OR = 1.02, 95%CI: 0.64 to 1.63), localized reactions (OR = 0.69, 95%CI: 0.37 to 1.30), systemic reactions (OR = 1.00, 95%CI: 0.59 to 1.69), allergic reactions (OR = 5.11, 95%CI: 0.24 to 107.10), self-reported vaccination-related adverse events (OR = 1.61, 95%CI: 0.56 to 4.63), and disease flares after vaccination (OR = 1.00, 95%CI: 0.14 to 7.28). CONCLUSION: Despite the reduced immune response and host protection in SLE patients post-Corona Virus Disease 2019 (COVID-19) and influenza vaccines compared to the healthy population, safety profiles are comparable. Therefore, it is recommended that SLE patients receive COVID-19 and influenza viral vaccines to fortify their resistance.


Assuntos
Anticorpos Antivirais , Imunidade Humoral , Lúpus Eritematoso Sistêmico , Estudos Observacionais como Assunto , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Imunidade Humoral/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Feminino , Masculino , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/administração & dosagem
5.
Plants (Basel) ; 13(16)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39204630

RESUMO

The passion fruit, Passiflora edulis, recognized for its rich nutritional properties, has long been used for its varied ethnobotanical applications. This study investigates the therapeutic potential of P. edulis var. Tainung No. 1 rind extracts by examining their polyphenolic content (TPC), total flavonoid content (TFC), anti-skin aging activities against key enzymes such as elastase, tyrosinase, and hyaluronidase, and their ability to inhibit bacterial growth, single-stranded DNA-binding protein (SSB), and their cytotoxic effects on oral carcinoma cells. The acetone extract from the rind exhibited the highest levels of TPC, TFC, anti-SSB, and antibacterial activities. The antibacterial effectiveness of the acetone-extracted rind was ranked as follows: Escherichia coli > Pseudomonas aeruginosa > Staphylococcus aureus. A titration curve for SSB inhibition showed an IC50 value of 313.2 µg/mL, indicating the potency of the acetone extract in inhibiting SSB. It also significantly reduced the activity of enzymes associated with skin aging, particularly tyrosinase, with a 54.5% inhibition at a concentration of 100 µg/mL. Gas chromatography-mass spectrometry (GC-MS) analysis tentatively identified several major bioactive compounds in the acetone extract, including stigmast-5-en-3-ol, vitamin E, palmitic acid, stigmasterol, linoleic acid, campesterol, and octadecanoic acid. Molecular docking studies suggested some of these compounds as potential inhibitors of tyrosinase and SSB. Furthermore, the extract demonstrated anticancer potential against Ca9-22 oral carcinoma cells by inhibiting cell survival, migration, and proliferation and inducing apoptosis. These results underscore the potential of P. edulis (Tainung No. 1) rind as a promising candidate for anti-skin aging, antibacterial, and anticancer applications, meriting further therapeutic investigation.

6.
Plants (Basel) ; 13(16)2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39204651

RESUMO

The tamarillo, or Solanum betaceum, recognized for its comprehensive nutritional profile, has long been valued for its diverse ethnobotanical uses. This study delves into the potential therapeutic applications of S. betaceum by analyzing its polyphenolic content (TPC), total flavonoid content (TFC), anti-skin aging activities against key enzymes like elastase, tyrosinase, and hyaluronidase, and its cytotoxic effects on oral carcinoma cells. Extracts from the seeds, pulp, and peel of red and yellow fruits were prepared using methanol, ethanol, and acetone. The highest TPC was found in the methanol extract from red fruit seeds (9.89 mg GAE/g), and the highest TFC was found in the methanol extract of yellow fruit peel (3.02 mg QUE/g). Some of these extracts significantly inhibited skin aging-associated enzymes with the red fruit seed extract (100 µg/mL) showing up to 50.4% inhibition of tyrosinase. Additionally, the red fruit seed extract obtained using methanol demonstrated potential anticancer effects against Ca9-22 oral carcinoma cells by inhibiting cell survival, migration, and proliferation as well as inducing apoptosis. These results underscore the potential of S. betaceum fruit extracts, especially from red fruit seeds, as promising agents for anti-skin aging and anticancer applications, meriting further exploration for therapeutic uses.

7.
Ann Med ; 56(1): 2381696, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39061119

RESUMO

OBJECTIVE: The current guidelines and canonical norms of diagnosis or treatment for Post-traumatic stress disorder (PTSD) with sleep disorder are still conflicting and have not yet reached a consensus. This study aimed to unravel the most effective countermeasures between two categories (psychotherapy and pharmacotherapy) put forward by the National Institute for Health and Clinical Excellence (NICE) and World Federation of Societies of Biological Psychiatry (WFSBP) respectively to treat PTSD individuals co-exist with sleep disorders. METHODS: Four databases, including PubMed, EMBASE, Cochrane Library, and APA PsyNet, were searched from inception to February 02, 2023. RESULTS: Twenty articles with 24 Randomized controlled trials (RCTs) and a total number of 1,647 participants were included. As demonstrated in the network meta-analysis comparison results, CBT-I (standardized mean differences (SMD) = -1.51,95% confidence interval (CI):-2.55 to -0.47), CBT-I plus IRT (SMD = -1.71, 95%CI:-3.39, -0.03), prazosin (SMD = -0.87,95%CI:-1.59 to -0.16) and hydroxyzine (SMD = -1.06, 95%CI: -1.94 to -0.19) significantly reduced PTSD symptoms compared with placebo. In contrast to placebo, CBT-I (SMD = -5.61,95%CI:-8.82 to -2.40) significantly improved sleep quality. For nightmare severity, IRT (SMD =-0.65, 95%CI:-1.00 to -0.31), prazosin (SMD = -1.20,95%CI:-1.72 to -0.67) and hydroxyzine (SMD = -0.98,95%CI:-1.58 to -0.37) significantly reduced nightmare severity in comparison with placebo. CONCLUSIONS: This study suggested that under most circumstances, psychotherapy namely CBT-I had a favorable profile, but pharmacotherapy with prazosin was effective in managing nightmare severity. The sole avail of CBT-I was recommended to improving sleep quality while CBT-I and CBT-I plus IRT showed excellent management of PTSD symptom severity. Exposure to CBT-I isrecommended for depression. The relevant clinical guidelines for the management of individuals with PTSD and sleep disorders may regard this as a reference. PROSPERO: CRD42023415240.


Assuntos
Metanálise em Rede , Prazosina , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos do Sono-Vigília , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/terapia , Prazosina/uso terapêutico , Transtornos do Sono-Vigília/tratamento farmacológico , Transtornos do Sono-Vigília/terapia , Terapia Cognitivo-Comportamental/métodos , Psicoterapia/métodos , Resultado do Tratamento , Masculino , Feminino , Adulto , Dessensibilização e Reprocessamento através dos Movimentos Oculares/métodos , Hidroxizina/uso terapêutico
8.
Int J Mol Sci ; 25(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38892307

RESUMO

Carnivorous pitcher plants from the genus Nepenthes are renowned for their ethnobotanical uses. This research explores the therapeutic potential of Nepenthes miranda leaf extract against nonstructural protein 9 (Nsp9) of SARS-CoV-2 and in treating human non-small cell lung carcinoma (NSCLC) cell lines. Nsp9, essential for SARS-CoV-2 RNA replication, was expressed and purified, and its interaction with ssDNA was assessed. Initial tests with myricetin and oridonin, known for targeting ssDNA-binding proteins and Nsp9, respectively, did not inhibit the ssDNA-binding activity of Nsp9. Subsequent screenings of various N. miranda extracts identified those using acetone, methanol, and ethanol as particularly effective in disrupting Nsp9's ssDNA-binding activity, as evidenced by electrophoretic mobility shift assays. Molecular docking studies highlighted stigmast-5-en-3-ol and lupenone, major components in the leaf extract of N. miranda, as potential inhibitors. The cytotoxic properties of N. miranda leaf extract were examined across NSCLC lines H1975, A549, and H838, focusing on cell survival, apoptosis, and migration. Results showed a dose-dependent cytotoxic effect in the following order: H1975 > A549 > H838 cells, indicating specificity. Enhanced anticancer effects were observed when the extract was combined with afatinib, suggesting synergistic interactions. Flow cytometry indicated that N. miranda leaf extract could induce G2 cell cycle arrest in H1975 cells, potentially inhibiting cancer cell proliferation. Gas chromatography-mass spectrometry (GC-MS) enabled the tentative identification of the 19 most abundant compounds in the leaf extract of N. miranda. These outcomes underscore the dual utility of N. miranda leaf extract in potentially managing SARS-CoV-2 infection through Nsp9 inhibition and offering anticancer benefits against lung carcinoma. These results significantly broaden the potential medical applications of N. miranda leaf extract, suggesting its use not only in traditional remedies but also as a prospective treatment for pulmonary diseases. Overall, our findings position the leaf extract of N. miranda as a promising source of natural compounds for anticancer therapeutics and antiviral therapies, warranting further investigation into its molecular mechanisms and potential clinical applications.


Assuntos
Tratamento Farmacológico da COVID-19 , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Extratos Vegetais , Folhas de Planta , SARS-CoV-2 , Humanos , Células A549 , Antivirais/farmacologia , Antivirais/química , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , COVID-19/virologia , COVID-19/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/antagonistas & inibidores
9.
Plants (Basel) ; 13(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38592804

RESUMO

The carnivorous pitcher plants of the genus Nepenthes have long been known for their ethnobotanical applications. In this study, we prepared various extracts from the pitcher, stem, and leaf of Nepenthes miranda using 100% ethanol and assessed their inhibitory effects on key enzymes related to skin aging, including elastase, tyrosinase, and hyaluronidase. The cytotoxicity of the stem extract of N. miranda on H838 human lung carcinoma cells were also characterized by effects on cell survival, migration, proliferation, apoptosis induction, and DNA damage. The cytotoxic efficacy of the extract was enhanced when combined with the chemotherapeutic agent 5-fluorouracil (5-FU), indicating a synergistic effect. Flow cytometry analysis suggested that the stem extract might suppress H838 cell proliferation by inducing G2 cell cycle arrest, thereby inhibiting carcinoma cell proliferation. Gas chromatography-mass spectrometry (GC-MS) enabled the tentative identification of the 15 most abundant compounds in the stem extract of N. miranda. Notably, the extract showed a potent inhibition of the human RPA32 protein (huRPA32), critical for DNA replication, suggesting a novel mechanism for its anticancer action. Molecular docking studies further substantiated the interaction between the extract and huRPA32, highlighting bioactive compounds, especially the two most abundant constituents, stigmast-5-en-3-ol and plumbagin, as potential inhibitors of huRPA32's DNA-binding activity, offering promising avenues for cancer therapy. Overall, our findings position the stem extract of N. miranda as a promising source of natural compounds for anticancer therapeutics and anti-skin-aging treatments, warranting further investigation into its molecular mechanisms and potential clinical applications.

10.
Mol Carcinog ; 63(7): 1362-1377, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38656551

RESUMO

Acetyl-CoAacyltransferase2 (ACAA2) is a key enzyme in the fatty acid oxidation pathway that catalyzes the final step of mitochondrial ß oxidation, which plays an important role in fatty acid metabolism. The expression of ACAA2 is closely related to the occurrence and malignant progression of tumors. However, the function of ACAA2 in ovarian cancer is unclear. The expression level and prognostic value of ACAA2 were analyzed by databases. Gain and loss of function were carried out to explore the function of ACAA2 in ovarian cancer. RNA-seq and bioinformatics methods were applied to illustrate the regulatory mechanism of ACAA2. ACAA2 overexpression promoted the growth, proliferation, migration, and invasion of ovarian cancer, and ACAA2 knockdown inhibited the malignant progression of ovarian cancer as well as the ability of subcutaneous tumor formation in nude mice. At the same time, we found that OGT can induce glycosylation modification of ACAA2 and regulate the karyoplasmic distribution of ACAA2. OGT plays a vital role in ovarian cancer as a function of oncogenes. In addition, through RNA-seq sequencing, we found that ACAA2 regulates the expression of DIXDC1. ACAA2 regulated the malignant progression of ovarian cancer through the WNT/ß-Catenin signaling pathway probably. ACAA2 is an oncogene in ovarian cancer and has the potential to be a target for ovarian cancer therapy.


Assuntos
Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Animais , Camundongos , Linhagem Celular Tumoral , Movimento Celular , Via de Sinalização Wnt , Prognóstico , Carcinogênese/genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-38530711

RESUMO

Ultrasonic synthetic aperture focus techniques (SAFTs) using less than the total number of available array elements to transmit ("sparse" transmissions) have been recently used in both medical imaging and industrial nondestructive testing (NDT) imaging to increase test speed and simplify multiplexer hardware. The challenge of sparse arrays is to obtain a reasonable image quality given the reduced transmitter-receiver combinations available to the beamforming process. This article proposes a "ultrasparse" SAFT method that employs a minimum number of transmitter elements (from one to four elements only) to obtain an entire full-matrix capture (FMC) set of waveforms. Specifically, a "virtual" FMC is obtained from normalized cross-power spectra between each array element pair in an implementation of "passive" ultrasonic sensing. In order to maintain high image quality without sacrificing imaging speed (e.g., applying a minimal initial time delay and keeping a short time recording window), several key steps have to be taken in this "passive" imaging mode, specifically: 1) the use of carefully designed segment-averaged normalized cross-power spectrum (NCPS) for robust passive reconstruction of the ultrasonic impulse response function (IRF) between two receivers; 2) the use of both the causal and acausal portions of the passively reconstructed IRFs; and 3) the compounding of multiple wave modes in the beamforming process. These steps also ensure the elimination of the near-field blind zone hence potentially enabling near-field imaging. The article first reviews the theory of passive IRF reconstruction between two receivers, comparing time-averaged cross correlation versus segment-averaged NCPS, and then demonstrates the application to ultrasparse SAFT FMC imaging of drilled holes in an aluminum block using a linear transducer array where only one to four elements are used in transmission.

12.
Int J Mol Sci ; 25(6)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38542377

RESUMO

5-Fluorouracil (5-FU) stands as one of the most widely prescribed chemotherapeutics. Despite over 60 years of study, a systematic synopsis of how 5-FU binds to proteins has been lacking. Investigating the specific binding patterns of 5-FU to proteins is essential for identifying additional interacting proteins and comprehending their medical implications. In this review, an analysis of the 5-FU binding environment was conducted based on available complex structures. From the earliest complex structure in 2001 to the present, two groups of residues emerged upon 5-FU binding, classified as P- and R-type residues. These high-frequency interactive residues with 5-FU include positively charged residues Arg and Lys (P type) and ring residues Phe, Tyr, Trp, and His (R type). Due to their high occurrence, 5-FU binding modes were simplistically classified into three types, based on interactive residues (within <4 Å) with 5-FU: Type 1 (P-R type), Type 2 (P type), and Type 3 (R type). In summary, among 14 selected complex structures, 8 conform to Type 1, 2 conform to Type 2, and 4 conform to Type 3. Residues with high interaction frequencies involving the N1, N3, O4, and F5 atoms of 5-FU were also examined. Collectively, these interaction analyses offer a structural perspective on the specific binding patterns of 5-FU within protein pockets and contribute to the construction of a structural interactome delineating the associations of the anticancer drug 5-FU.


Assuntos
Antineoplásicos , Fluoruracila , Fluoruracila/metabolismo , Proteínas
13.
J Nanobiotechnology ; 22(1): 5, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38169397

RESUMO

We have successfully generated oligonucleotide aptamers (Apts) and monoclonal antibodies (mAbs) targeting the recombinant nucleocapsid (N) protein of SARS-CoV-2. Apts were obtained through seven rounds of systematic evolution of ligands by exponential enrichment (SELEX), while mAbs were derived from the 6F6E11 hybridoma cell line. Leveraging these Apts and mAbs, we have successfully devised two innovative and remarkably sensitive detection techniques for the rapid identification of SARS-CoV-2 N protein in nasopharyngeal samples: the enzyme-linked aptamer-antibody sandwich assay (ELAAA) and the hybrid lateral flow strip (hybrid-LFS). ELAAA exhibited an impressive detection limit of 0.1 ng/mL, while hybrid-LFS offered a detection range of 0.1 - 0.5 ng/mL. In the evaluation using ten nasopharyngeal samples spiked with known N protein concentrations, ELAAA demonstrated an average recovery rate of 92%. Additionally, during the assessment of five nasopharyngeal samples from infected individuals and ten samples from healthy volunteers, hybrid-LFS displayed excellent sensitivity and specificity. Our study introduces a novel and efficient on-site approach for SARS-CoV-2 detection in nasopharyngeal samples. The reliable hybrid Apt-mAb strategy not only advances virus diagnostic methods but also holds promise in combating the spread of related diseases.


Assuntos
Aptâmeros de Nucleotídeos , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/diagnóstico , Anticorpos Monoclonais , Sensibilidade e Especificidade
14.
Nat Aging ; 4(1): 62-79, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177329

RESUMO

The decline in stem cell function during aging may affect the regenerative capacity of mammalian organisms; however, the gene regulatory mechanism underlying this decline remains unclear. Here we show that the aging of neural stem and progenitor cells (NSPCs) in the male mouse brain is characterized by a decrease in the generation efficacy of proliferative NSPCs rather than the changes in lineage specificity of NSPCs. We reveal that the downregulation of age-dependent genes in NSPCs drives cell aging by decreasing the population of actively proliferating NSPCs while increasing the expression of quiescence markers. We found that epigenetic deregulation of the MLL complex at promoters leads to transcriptional inactivation of age-dependent genes, highlighting the importance of the dynamic interaction between histone modifiers and gene regulatory elements in regulating transcriptional program of aging cells. Our study sheds light on the key intrinsic mechanisms driving stem cell aging through epigenetic regulators and identifies potential rejuvenation targets that could restore the function of aging stem cells.


Assuntos
Células-Tronco Neurais , Animais , Camundongos , Masculino , Envelhecimento/genética , Senescência Celular/genética , Encéfalo , Epigênese Genética , Mamíferos
15.
Artigo em Inglês | MEDLINE | ID: mdl-38096096

RESUMO

This article discusses the application of sparse synthetic aperture focusing techniques (SAFTs) for fast and accurate ultrasonic nondestructive testing (NDT) imaging of solids in cases where a wedge is required between the transducer array and the test medium. A wedge is often used to appropriately direct the ultrasonic beams when testing for structural defects at particular orientations or when inspecting parts with particular geometries (e.g., waveguides). Both the virtual element (VE) and the plane-wave (PW) modalities of sparse-firing SAFT are examined for the wedge case that requires particular considerations in the beamforming algorithms for the wave refractions and mode conversions occurring at the wedge-medium interface. The method of wave mode compounding is also examined for this application to increase the array gain without increasing its physical aperture. Numerical simulations and experimental tests demonstrate the potential improvements in speed and accuracy obtainable by sparse SAFT adapted to wedge-transducer cases compared to a traditional full matrix capture (FMC) imaging mode. A practical implementation of the imaging of transverse defects in rail tracks is also presented.

16.
Biochem Biophys Res Commun ; 692: 149351, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38056157

RESUMO

Dihydropyrimidinase (DHPase) plays a crucial role in pyrimidine degradation, showcasing a broad substrate specificity that extends beyond pyrimidine catabolism, hinting at additional roles for this ancient enzyme. In this study, we solved the crystal structure of Pseudomonas aeruginosa DHPase (PaDHPase) complexed with the neurotransmitter γ-aminobutyric acid (GABA) at a resolution of 1.97 Å (PDB ID 8WQ9). Our structural analysis revealed two GABA binding sites in each monomer of PaDHPase. Interactions between PaDHPase and GABA molecules, involving residues within a contact distance of <4 Å, were examined. In silico analyses via PISA and PLIP software revealed hydrogen bonds formed between the side chain of Cys318 and GABA 1, as well as the main chains of Ser333, Ile335, and Asn337 with GABA 2. Comparative structural analysis between GABA-bound and unbound states unveiled significant conformational changes at the active site, particularly within dynamic loop I, supporting the conclusion that PaDHPase binds GABA through the loop-out mechanism. Building upon this molecular evidence, we discuss and propose a working model. The study expands the GABA interactome by identifying DHPase as a novel GABA-interacting protein and provides structural insight into the interaction between a dimetal center in the protein's active site and GABA. Further investigations are warranted to explore potential interactions of GABA with other DHPase-like proteins and to understand whether DHPase may have additional regulatory and physiological roles in the cell, extending beyond pyrimidine catabolism.


Assuntos
Amidoidrolases , Ácido gama-Aminobutírico , Amidoidrolases/química , Ácido gama-Aminobutírico/metabolismo , Proteínas , Neurotransmissores , Pirimidinas
17.
Ann Epidemiol ; 89: 21-28, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38042439

RESUMO

BACKGROUND: Herpes simplex virus (HSV) is an opportunistic infection antigen in solid organ transplant (SOT) recipients. However, this phenomenon has received limited attention from epidemiologists. Our study aims to determine the HSV infection risk in SOT recipients. METHODS: This was a nationwide population-based cross-sectional study based on the National Health Insurance Research Database from 2002 to 2015. We used propensity score matching to avoid selection bias and analyzed the association between HSV infection and SOT recipients with multiple logistic regression analysis. RESULTS: At a 3-year follow-up, SOT recipients had a higher risk of developing HSV, with an adjusted odds ratio (aOR) of 3.28 (95% confidence interval (CI), 2.51-4.29). Moreover, at 6-month, 1-year, and 2-year follow-ups, SOT recipients also had an increased risk of HSV than general patients with aORs of 3.85 (95% CI, 2.29-6.49), 4.27 (95% CI, 2.86-6.36), and 3.73 (95% CI, 2.74-5.08), respectively. In the subgroup analysis, lung transplant recipients (aOR = 8.01; 95% CI, 2.39-26.88) exhibited a significantly higher chance of HSV among SOT recipients, followed by kidney transplant recipients (aOR = 3.33; 95% CI, 2.11-5.25) and liver transplant recipients (aOR = 3.15; 95% CI, 2.28-4.34). CONCLUSION: HSV can develop at any time after organ transplantation. SOT recipients had a higher risk of HSV infection than the general population at 6 months, 1 year, 2 years, and 3 years after transplantation, with the highest chance at 1 year after. In addition, the patients who underwent lung transplantion were at higher risk for HSV infection than liver or kidney transplant recipients.


Assuntos
Herpes Simples , Transplante de Órgãos , Humanos , Estudos Transversais , Transplantados , Herpes Simples/epidemiologia , Herpes Simples/etiologia , Transplante de Órgãos/efeitos adversos , Razão de Chances
18.
Plants (Basel) ; 12(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37896126

RESUMO

The authors would like to supplement some methodology information including the controls in the originally published version of this manuscript [...].

19.
Int J Mol Sci ; 24(19)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37834349

RESUMO

Single-stranded DNA-binding proteins (SSBs) play a crucial role in DNA metabolism by binding and stabilizing single-stranded DNA (ssDNA) intermediates. Through their multifaceted roles in DNA replication, recombination, repair, replication restart, and other cellular processes, SSB emerges as a central player in maintaining genomic integrity. These attributes collectively position SSBs as essential guardians of genomic integrity, establishing interactions with an array of distinct proteins. Unlike Escherichia coli, which contains only one type of SSB, some bacteria have two paralogous SSBs, referred to as SsbA and SsbB. In this study, we identified Staphylococcus aureus SsbA (SaSsbA) as a fresh addition to the roster of the anticancer drug 5-fluorouracil (5-FU) binding proteins, thereby expanding the ambit of the 5-FU interactome to encompass this DNA replication protein. To investigate the binding mode, we solved the complexed crystal structure with 5-FU at 2.3 Å (PDB ID 7YM1). The structure of glycerol-bound SaSsbA was also determined at 1.8 Å (PDB ID 8GW5). The interaction between 5-FU and SaSsbA was found to involve R18, P21, V52, F54, Q78, R80, E94, and V96. Based on the collective results from mutational and structural analyses, it became evident that SaSsbA's mode of binding with 5-FU diverges from that of SaSsbB. This complexed structure also holds the potential to furnish valuable comprehension regarding how 5-FU might bind to and impede analogous proteins in humans, particularly within cancer-related signaling pathways. Leveraging the information furnished by the glycerol and 5-FU binding sites, the complexed structures of SaSsbA bring to the forefront the potential viability of several interactive residues as potential targets for therapeutic interventions aimed at curtailing SaSsbA activity. Acknowledging the capacity of microbiota to influence the host's response to 5-FU, there emerges a pressing need for further research to revisit the roles that bacterial and human SSBs play in the realm of anticancer therapy.


Assuntos
Antineoplásicos , Proteínas de Bactérias , Humanos , Proteínas de Bactérias/metabolismo , Glicerol , DNA de Cadeia Simples , Fluoruracila/farmacologia , Escherichia coli/metabolismo , Replicação do DNA , Antineoplásicos/farmacologia , Ligação Proteica/genética
20.
Discov Oncol ; 14(1): 157, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37639158

RESUMO

BACKGROUND: The incidence of ovarian cancer ranks third among gynecologic malignancies, but the mortality rate ranks first. METHODS: The expression of GAS5 is low in ovarian cancer and is associated with the low survival of ovarian cancer patients according to public ovarian cancer databases. GAS5 overexpression inhibited ovarian malignancy by affecting the proliferation and migratory abilities in OVCAR3 and A2780 cells. GAS5 overexpression increased the rate of cell apoptosis, and the cells were blocked in the G1 phase as assessed by flow cytometry. RESULTS: We found that hnRNPK was a potential target gene, which was regulated negatively by GAS5 based on RNA-pulldown and mass spectrometry analysis. Mechanistically, GAS5 affected the inhibition of the PI3K/AKT/mTOR pathways and bound the protein of hnRNPK, which influenced hnRNPK stability. Furthermore, rescue assays demonstrated hnRNPK was significantly involved in the progression of ovarian cancer. CONCLUSIONS: Our study showed one of the mechanisms that GAS5 inhibited ovarian cancer metastasis by down-regulating hnRNPK expression, and GAS5 can be used to predict the prognosis of ovarian cancer patients.

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