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1.
Biomol NMR Assign ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38844727

RESUMO

The contribution of Fe(II)-oxidizing bacteria to iron cycling in freshwater, groundwater, and marine environments has been widely recognized in recent years. These organisms perform extracellular electron transfer (EET), which constitutes the foundations of bioelectrochemical systems for the production of biofuels and bioenergy. It was proposed that the Gram-negative bacterium Sideroxydans lithotrophicus ES-1 oxidizes soluble ferrous Fe(II) at the surface of the cell and performs EET through the Mto redox pathway. This pathway is composed by the periplasmic monoheme cytochrome MtoD that is proposed to bridge electron transfer between the cell exterior and the cytoplasm. This makes its functional and structural characterization, as well as evaluating the interaction process with its physiological partners, essential for understanding the mechanisms underlying EET. Here, we report the complete assignment of the heme proton and carbon signals together with a near-complete assignment of 1H, 13C and 15N backbone and side chain resonances for the reduced, diamagnetic form of the protein. These data pave the way to identify and structurally map the molecular interaction regions between the cytochrome MtoD and its physiological redox partners, to explore the EET processes of S. lithotrophicus ES-1.

2.
Carbohydr Polym ; 337: 122112, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710545

RESUMO

The growing concerns on environmental pollution and sustainability have raised the interest on the development of functional biobased materials for different applications, including food packaging, as an alternative to the fossil resources-based counterparts, currently available in the market. In this work, functional wood inspired biopolymeric nanocomposite films were prepared by solvent casting of suspensions containing commercial beechwood xylans, cellulose nanofibers (CNF) and lignosulfonates (magnesium or sodium), in a proportion of 2:5:3 wt%, respectively. All films presented good homogeneity, translucency, and thermal stability up to 153 °C. The incorporation of CNF into the xylan/lignosulfonates matrix provided good mechanical properties to the films (Young's modulus between 1.08 and 3.79 GPa and tensile strength between 12.75 and 14.02 MPa). The presence of lignosulfonates imparted the films with antioxidant capacity (DPPH radical scavenging activity from 71.6 to 82.4 %) and UV barrier properties (transmittance ≤19.1 % (200-400 nm)). Moreover, the films obtained are able to successfully delay the browning of packaged fruit stored over 7 days at 4 °C. Overall, the obtained results show the potential of using low-cost and eco-friendly resources for the development of sustainable active food packaging materials.


Assuntos
Celulose , Embalagem de Alimentos , Lignina , Lignina/análogos & derivados , Nanocompostos , Nanofibras , Resistência à Tração , Madeira , Xilanos , Embalagem de Alimentos/métodos , Lignina/química , Nanocompostos/química , Celulose/química , Celulose/análogos & derivados , Madeira/química , Nanofibras/química , Xilanos/química , Antioxidantes/química , Frutas/química
3.
Sci Signal ; 16(816): eadh3449, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38113335

RESUMO

Interleukin-1 receptor (IL-1R)-associated kinases (IRAKs) are core effectors of Toll-like receptors (TLRs) and IL-1R in innate immunity. Here, we found that IRAK4 and IRAK1 together inhibited DNA damage-induced cell death independently of TLR or IL-1R signaling. In human cancer cells, IRAK4 was activated downstream of ATR kinase in response to double-strand breaks (DSBs) induced by ionizing radiation (IR). Activated IRAK4 then formed a complex with and activated IRAK1. The formation of this complex required the E3 ubiquitin ligase Pellino1, acting structurally but not catalytically, and the activation of IRAK1 occurred independently of extracellular signaling, intracellular TLRs, and the TLR/IL-1R signaling adaptor MyD88. Activated IRAK1 translocated to the nucleus in a Pellino2-dependent manner. In the nucleus, IRAK1 bound to the PIDD1 subunit of the proapoptotic PIDDosome and interfered with platform assembly, thus supporting cell survival. This noncanonical IRAK signaling pathway was also activated in response to other DSB-inducing agents. The loss of IRAK4, of IRAK4 kinase activity, of either Pellino protein, or of the nuclear localization sequence in IRAK1 sensitized p53-mutant zebrafish to radiation. Thus, the findings may lead to strategies for overcoming tumor resistance to conventional cancer treatments.


Assuntos
Quinases Associadas a Receptores de Interleucina-1 , Receptores de Interleucina-1 , Animais , Humanos , Quinases Associadas a Receptores de Interleucina-1/genética , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo , Peixe-Zebra/metabolismo , Transdução de Sinais , Receptores Toll-Like/metabolismo , Dano ao DNA , Apoptose
4.
bioRxiv ; 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36798275

RESUMO

Interleukin-1 receptor (IL-1R)-associated kinases (IRAKs) are core effectors of Toll-like receptor (TLR) and IL-1R signaling, with no reported roles outside of innate immunity. We find that vertebrate cells exposed to ionizing radiation (IR) sequentially activate IRAK4 and IRAK1 through a phosphorylation cascade mirroring that induced by TLR/IL-1R, resulting in a potent anti-apoptotic response. However, IR-induced IRAK1 activation does not require the receptors or the IRAK4/1 adaptor protein MyD88, and instead of remaining in the cytoplasm, the activated kinase is immediately transported to the nucleus via a conserved nuclear localization signal. We identify: double-strand DNA breaks (DSBs) as the biologic trigger for this pathway; the E3 ubiquitin ligase Pellino1 as the scaffold enabling IRAK4/1 activation in place of TLR/IL-1R-MyD88; and the pro-apoptotic PIDDosome (PIDD1-RAIDD-caspase-2) as a critical downstream target in the nucleus. The data delineate a non-canonical IRAK signaling pathway derived from, or ancestral to, TLR signaling. This DSB detection pathway, which is also activated by genotoxic chemotherapies, provides multiple actionable targets for overcoming tumor resistance to mainstay cancer treatments.

5.
J Inorg Biochem ; 239: 112089, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36502664

RESUMO

CISD3 is a mitochondrial protein belonging to the NEET proteins family, bearing two [Fe2S2] clusters coordinated by CDGSH domains. At variance with the other proteins of the NEET family, very little is known about its structure-function relationships. NMR is the only technique to obtain information at the atomic level in solution on the residues involved in intermolecular interactions; however, in paramagnetic proteins this is limited by the broadening of signals of residues around the paramagnetic center. Tailored experiments can revive signals of the cluster surrounding; however, signals identification without specific residue assignment remains useless. Here, we show how paramagnetic relaxation can drive the signal assignment of residues in the proximity of the paramagnetic center(s). This allowed us to identify the potential key players of the biological function of the CISD3 protein.


Assuntos
Proteínas Ferro-Enxofre , Imageamento por Ressonância Magnética , Humanos , Sítios de Ligação , Proteínas Ferro-Enxofre/química , Ligantes , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Proteínas Mitocondriais/química
6.
J Surg Case Rep ; 2022(7): rjac334, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35892123

RESUMO

Liver abscesses are a common complication in patients with amebiasis. Rarely, these will rupture across the diaphragm causing life-threatening empyemas. Evidence justifies performing surgical debridement or decortication for their treatment, given the better overall performance in comparison to open surgeries. However, no current guideline specifies which is the best approach. This report presents the case of a 39-year-old male with clinical, radiographical and microbiological evidence of an amebic empyema secondary to an amebic liver abscess, who received treatment by video-assisted thoracoscopy. The case description highlights the surgical technique, findings and operative outcomes that could be taken into consideration by other physicians to timely manage similar cases. The latter is especially relevant in underdeveloped and developing countries, where the burden of amebiasis appears to be greater. To the best of the authors' knowledge, this is the first description of a transdiaphragmatic amebic infection treated in a minimally invasive fashion.

7.
Neurourol Urodyn ; 41(7): 1573-1581, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35866192

RESUMO

PURPOSE: The artificial urinary sphincter (AUS) is one of the most effective surgical treatments for male urinary incontinence regardless of its severity. Current knowledge comes from high-volume centers, but little is known about the performance of this surgery from community practices. This study aims to report contemporary AUS performance in a nationwide observational study in Colombia. METHODS: Male patients who underwent AUS surgery with AMS 800™ between 2000 and 2020 in more than 17 centers and four cities were identified. Pre, intra, and postoperative characteristics were evaluated, mainly addressing patient reported outcomes measurements in the postoperative period. Retrospective and prospective data collection and descriptive analysis were completed. Kaplan-Meier analysis was used to determine AUS survival rate. RESULTS: Out of an initial 667 cases, a total of 215 patients met inclusion and exclusion criteria and were included. Mean age was 67 ± 9.4 years, and mean follow-up was 6.0 ± 4.4 years with maximum range of 14 years. The etiology of urinary incontinence was prostate cancer surgery in 141 (81%) of the cases. The rest of the cases were related to benign prostatic disease or spinal cord injury. It is noteworthy that out of 115 patients, only 59 (51.3%) reported previous formal pelvic floor rehabilitation. Subjective severity of urinary incontinence determined by a visual analog scale showed a decrease in 4.5 points after sphincter implantation. Sphincter removal was required in 50 (23.2%) cases. The main reasons for implant removal were urethral erosion and infection. The sphincter survival rate at 2, 5, 8, 10, and 14 years was 76%, 70%, 60%, 57%, and 17%, respectively. Of the subjects at the last follow-up with the device still in place, 80.7% defined their urinary condition as "does not cause or causes minor discomfort," and 99% would recommend the device to a friend or relative in the same condition. CONCLUSIONS: This series from a community-based practice shows the lack of adherence to clinical practice guidelines and the lack of standardized data collection. In contrast, this study provides real-world data on explantation and revision rates, allows physicians to inform patients and to have clear metrics for a shared decision-making process before the procedure.


Assuntos
Incontinência Urinária por Estresse , Incontinência Urinária , Esfíncter Urinário Artificial , Adolescente , Humanos , Masculino , Implantação de Prótese/métodos , Estudos Retrospectivos , Resultado do Tratamento , Incontinência Urinária/complicações , Incontinência Urinária/cirurgia , Incontinência Urinária por Estresse/cirurgia , Esfíncter Urinário Artificial/efeitos adversos
8.
Sci Rep ; 12(1): 10140, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710591

RESUMO

Lung cancer has been the most common cancer worldwide for several decades. The outcomes of patients with locally advanced lung cancer remain dismal, and only a minority of patients survive more than 5 years. However, tumor therapeutic resistance mechanisms are poorly studied. Identification of therapeutic resistance pathways in lung cancer in order to increase the sensitivity of lung tumor cells to therapeutic agents is a crucial but challenging need. To identify novel genes that modulate the response to platinum-based therapy, we performed a genome-wide high-throughput ribonucleic acid interference (RNAi) screen via transfection of human lung cancer (PC9) cells with a viral short hairpin RNA (shRNA) library. We further validated a potential target via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and clonogenic survival assays on PC9 and A549 lung tumor cells transfected with small interfering RNAs (siRNAs) to successfully downregulate protein expression and then treated with increasing doses of cisplatin or X-ray radiation. We determined protein expression by immunohistochemistry (IHC) after chemoradiotherapy and analyzed gene expression-based survival outcomes in two cohorts of human non-small-cell lung cancer (NSCLC) patients. The screen identified several targets involved in epithelial-to-mesenchymal transition (EMT), including Smurf1, Smurf2, YAP1, and CEBPZ, and glycolytic pathway proteins, including PFKFB3. Furthermore, we found that the small molecule proteasome inhibitor bortezomib significantly downregulated Smurf2 in lung cancer cells. The addition of bortezomib in combination with cisplatin and radiation therapy in PC9 and A549 cells led to an increase in deoxyribonucleic acid (DNA) double-strand breaks with increased numbers of γ-H2AX-positive cells and upregulation of apoptosis. Finally, we found that Smurf2 protein expression was upregulated in situ after treatment with cisplatin and radiation therapy in a relevant cohort of patients with stage III NSCLC. Additionally, Smurf2 gene expression was the strongest predictor of survival in patients with squamous NSCLC after chemotherapy or chemoradiotherapy. We successfully identified and validated Smurf2 as both a common modulator of resistance and an actionable target in lung cancer. These results suggest the urgent need to investigate clinical Smurf2 inhibition via bortezomib in combination with cisplatin and radiation for patients with locally advanced NSCLC.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/genética , Bortezomib/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , RNA Interferente Pequeno/metabolismo , Tolerância a Radiação/genética , Ubiquitina-Proteína Ligases/genética
9.
Adv Sci (Weinh) ; 9(4): e2104759, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34898027

RESUMO

The H19X-encoded miR-424(322)/503 cluster regulates multiple cellular functions. Here, it is reported for the first time that it is also a critical linchpin of fat mass expansion. Deletion of this miRNA cluster in mice results in obesity, while increasing the pool of early adipocyte progenitors and hypertrophied adipocytes. Complementary loss and gain of function experiments and RNA sequencing demonstrate that miR-424(322)/503 regulates a conserved genetic program involved in the differentiation and commitment of white adipocytes. Mechanistically, it is demonstrated that miR-424(322)/503 targets γ-Synuclein (SNCG), a factor that mediates this program rearrangement by controlling metabolic functions in fat cells, allowing adipocyte differentiation and adipose tissue enlargement. Accordingly, diminished miR-424(322) in mice and obese humans co-segregate with increased SNCG in fat and peripheral blood as mutually exclusive features of obesity, being normalized upon weight loss. The data unveil a previously unknown regulatory mechanism of fat mass expansion tightly controlled by the miR-424(322)/503 through SNCG.


Assuntos
Tecido Adiposo/metabolismo , Diferenciação Celular , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , gama-Sinucleína/metabolismo , Adipogenia , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/genética , gama-Sinucleína/genética
10.
Cell Rep ; 35(4): 109049, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33910004

RESUMO

Transforming growth factor ß (TGF-ß) family ligands are key regulators of dendritic cell (DC) differentiation and activation. Epidermal Langerhans cells (LCs) require TGF-ß family signaling for their differentiation, and canonical TGF-ß1 signaling secures a non-activated LC state. LCs reportedly control skin inflammation and are replenished from peripheral blood monocytes, which also give rise to pro-inflammatory monocyte-derived DCs (moDCs). By studying mechanisms in inflammation, we previously screened LCs versus moDCs for differentially expressed microRNAs (miRNAs). This revealed that miR-424/503 is the most strongly inversely regulated (moDCs > LCs). We here demonstrate that miR-424/503 is induced during moDC differentiation and promotes moDC differentiation in human and mouse. Inversely, forced repression of miR-424 during moDC differentiation facilitates TGF-ß1-dependent LC differentiation. Mechanistically, miR-424/503 deficiency in monocyte/DC precursors leads to the induction of TGF-ß1 response genes critical for LC differentiation. Therefore, the miR-424/503 gene cluster plays a decisive role in anti-inflammatory LC versus pro-inflammatory moDC differentiation from monocytes.


Assuntos
Anti-Inflamatórios/uso terapêutico , Células de Langerhans/imunologia , MicroRNAs/metabolismo , Família Multigênica/genética , Fator de Crescimento Transformador beta/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Diferenciação Celular , Humanos , Camundongos , Transdução de Sinais
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