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1.
Antibiotics (Basel) ; 13(3)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38534635

RESUMO

Antimicrobial resistance is a critical challenge due to the overuse of conventional antimicrobials, and alternative solutions are urgently needed. This study investigates the efficacy of compounds derived from lactic acid bacteria (LAB) fermentation combined with antibiotics against multidrug-resistant pathogens isolated from clinical cases in a hospital setting. Strains of Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecium and faecalis were isolated and selected from blood, respiratory, and urine samples. They were tested against the fermentation products from the Ingulados LAB collection (BAL5, BAL6, BAL8, BAL13, and BAL16), recognized for their antimicrobial efficacy against veterinary pathogens. The activity against multidrug-resistant (MDR) pathogens was evaluated initially, followed by synergy tests using checkerboard assays and subsequent analysis. Bioinformatic assessments and supernatant treatments were performed to characterize the nature of the compounds responsible for the antimicrobial activity. Notably, BAL16 exhibited significant growth inhibition against multidrug-resistant E. faecium. Synergy tests highlighted its combined activity with tetracycline through FICI and surface analysis and bioinformatic analysis unveiled the protein fraction containing bacteriocins as the underlying mechanism. This study highlights BAL16 fermentation products potential as valuable antimicrobial agents against MDR E. faecium infections, attributed to bacteriocins. Further in-depth studies are necessary for complete bacteriocin characterization.

2.
Radiother Oncol ; 194: 110193, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38432310

RESUMO

BACKGROUND AND PURPOSE: Multicatheter breast brachytherapy is a standard technique for accelerated partial breast irradiation (APBI) in early breast cancer patients. Intraoperative multicatheter breast implant (IOMBI) followed by perioperative high-dose-rate brachytherapy (PHDRBT) offers a novel and advantageous approach. We present long-term oncological, toxicity, and cosmesis outcomes for a well-experienced single institution. MATERIALS AND METHODS: Eligible women aged ≥ 40 years with clinically and radiologically confirmed unifocal invasive or in situ ≤ 3 cm breast tumors underwent IOMBI during breast-conserving surgery. Patients meeting APBI criteria by definitive pathologic results received 3.4 Gy × 10fx with PHDRBT. Patients not suitable for APBI received PHDRBT-boost followed by WBRT. RESULTS: A total of 171 patients underwent IOMBI during BCS, 120 patients (70.1 %) were suitable for APBI and 51 (29.8 %) for anticipated PHDRBT-boost. The median age was 61 years (range: 40-78), the median tumor size was 1.1 cm (range: 0.2-3.5), with a histological diagnosis of invasive ductal carcinoma in 78.9 % and ductal in situ in 21.1 %. A median of 9 catheters (range: 4-14) were used. For APBI, the median CTV and V100 were 40.8 cc (range: 8.6-99) and 35.4 cc (range: 7.2-94). The median of healthy breast tissue irradiated represents 7.2 % (range: 2.3-28 %) and the median local treatment duration was 10 days (range: 7-16). With a median follow-up of 8.8 years (range: 0.3-16.25), the 8-year local, locoregional, and distant control rates were 99 %, 98.1 %, and 100 %. G1-G2 late-toxicity rate was 53.4 %. Long-term cosmetic evaluation was excellent-good in 90.8 %. CONCLUSION: IOMBI&PHDRBT program reports excellent long-term oncological outcomes, with a reduction from unnecessary irradiation exposure which translates into low long-term toxicity and good cosmesis outcomes, especially on well-selected APBI patients.


Assuntos
Braquiterapia , Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Pessoa de Meia-Idade , Braquiterapia/métodos , Braquiterapia/instrumentação , Braquiterapia/efeitos adversos , Idoso , Adulto , Implantes de Mama , Mastectomia Segmentar , Dosagem Radioterapêutica , Resultado do Tratamento
4.
J Hum Kinet ; 90: 227-237, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38380300

RESUMO

This study compared the effects of a 6-week combined plyometric and sprint-training program on the sand to regular preseason training, on the athletic performance and technical actions of beach handball (BH) players. Athletes were randomly assigned either to the control (CG, n = 12; BH training only) or the experimental group (EG, n = 12; plyometric + sprint + BH training). Assessments conducted before and after the training period included a squat jump, a countermovement jump, the Abalakov jump, a 15-m sprint, a modified Course-Navette endurance test, and four sport-specific BH throwing speed tests: a standing penalty throw, a 3-step running throw, a jump throw, and a 360º jump throw. The training intervention enhanced all athletic performance measures (all, p < 0.05). In contrast, the only improvement in the CG included endurance performance (p< 0.05). Significant time-group differences were noted in favor of the EG compared to the CG (p< 0.05) in the squat jump, the countermovement jump, the Abalakov jump, the jump throw velocity and 360º jump throw velocity. In conclusion, compared to BH regular training, 6 weeks of sand surface preseason plyometric and sprint training combined with regular BH training induced greater improvements in athletic performance and specific skills in BH players.

5.
IEEE Trans Biomed Eng ; 71(2): 467-476, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37607156

RESUMO

Most therapeutic ultrasound devices place emitters and receivers in separate locations, so that the long therapeutic pulses (>1 ms) can be emitted while receivers monitor the procedure. However, with such placement, emitters and receivers are competing for the same space, producing a trade-off between emission efficiency and reception sensitivity. Taking advantage of recent studies demonstrating that short-pulse ultrasound can be used therapeutically, we aimed to develop a device that overcomes such trade-offs. The array was composed of emitter-receiver stacks, which enabled both emission and reception from the same location. Each element was made of a lead zirconate titanate (PZT)-polyvinylidene fluoride (PVDF) stack. The PZT (frequency: 500 kHz, diameter: 16 mm) was used for emission and the PVDF (thickness: 28 µm, diameter: 16 mm) for broadband reception. 32 elements were assembled in a 3D-printed dome-shaped frame (focal length: 150 mm; [Formula: see text]-number: 1) and was tested in free-field and through an ex-vivo human skull. In free-field, the array had a 4.5 × 4.5 × 32 mm focus and produced a peak-negative pressure (PNP) of 2.12 MPa at its geometric center. The electronic steering range was ±15 mm laterally and larger than ±15 mm axially. Through the skull, the array produced a PNP of 0.63 MPa. The PVDF elements were able to localize broadband microbubble emissions across the skull. We built the first multi-element array for short-pulse and microbubble-based therapeutic applications. Stacked arrays overcome traditional trade-offs between the transmission and reception quality and have the potential to create a step change in treatment safety and efficacy.


Assuntos
Polímeros de Fluorcarboneto , Microbolhas , Terapia por Ultrassom , Humanos , Ultrassonografia , Terapia por Ultrassom/métodos , Polivinil
6.
Vet Res ; 54(1): 91, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845774

RESUMO

The microbiota in humans and animals play crucial roles in defense against pathogens and offer a promising natural source for immunomodulatory products. However, the development of physiologically relevant model systems and protocols for testing such products remains challenging. In this study, we present an experimental condition where various natural products derived from the registered lactic acid bacteria Ligilactobacillus salivarius CECT 9609, known for their immunomodulatory activity, were tested. These products included live and inactivated bacteria, as well as fermentation products at different concentrations and culture times. Using our established model system, we observed no morphological changes in the airway epithelium upon exposure to Pasteurella multocida, a common respiratory pathogen. However, early molecular changes associated with the innate immune response were detected through transcript analysis. By employing diverse methodologies ranging from microscopy to next-generation sequencing (NGS), we characterized the interaction of these natural products with the airway epithelium and their potential beneficial effects in the presence of P. multocida infection. In particular, our discovery highlights that among all Ligilactobacillus salivarius CECT 9609 products tested, only inactivated cells preserve the conformation and morphology of respiratory epithelial cells, while also reversing or altering the natural immune responses triggered by Pasteurella multocida. These findings lay the groundwork for further exploration into the protective role of these bacteria and their derivatives.


Assuntos
Produtos Biológicos , Ligilactobacillus salivarius , Infecções por Pasteurella , Pasteurella multocida , Humanos , Animais , Imunidade Inata , Células Epiteliais , Produtos Biológicos/farmacologia , Infecções por Pasteurella/microbiologia , Infecções por Pasteurella/veterinária
7.
Hum Reprod ; 38(11): 2187-2195, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37697661

RESUMO

STUDY QUESTION: Is the abundance of certain biochemical compounds in human cumulus cells (CCs) related to oocyte quality? SUMMARY ANSWER: Malonate, 5-oxyproline, and erythronate were positively associated with pregnancy potential. WHAT IS KNOWN ALREADY: CCs are removed and discarded prior to ICSI, thereby constituting an interesting biological material on which to perform molecular analysis aimed to predict oocyte developmental competence. Mitochondrial DNA content and transcriptional analyses in CC have been shown to provide a poor predictive value of oocyte competence, but the untargeted analysis of biochemical compounds (metabolomics) has been unexplored. STUDY DESIGN, SIZE, DURATION: CCs were obtained from three groups of cumulus-oocyte complexes (COCs) of known developmental potential: oocytes not developing to blastocyst following ICSI (Bl-); oocytes developing to blastocyst but failing to establish pregnancy following embryo transfer (P-); and oocytes developing to blastocyst able to establish a pregnancy (P+). Metabolomics analyses were performed on 12 samples per group, each sample comprising the CC recovered from a single COC. PARTICIPANTS/MATERIALS, SETTING, METHODS: Human CC samples were obtained from IVF treatments. Only unfrozen oocytes and embryos not submitted to preimplantation genetic testing were included in the analysis. Metabolomics analysis was performed by ultra-high performance liquid chromatography-tandem mass spectroscopy. MAIN RESULTS AND THE ROLE OF CHANCE: The analysis identified 98 compounds, five of which were differentially abundant (P < 0.05) between groups: asparagine, proline, and malonate were less abundant in P- compared to Bl-, malonate and 5-oxoproline were less abundant in P- group compared to P+, and erythronate was less abundant in Bl- group compared to P+. No significant association between the abundance of the compounds identified and donor age or BMI was noted. LIMITATIONS, REASONS FOR CAUTION: Data dispersion and the lack of coherence between developmental groups preclude the direct use of metabolic markers in clinical practice, where the uterine environment plays a major role in pregnancy outcome. The abundance of other compounds not detected by the analysis may be associated with oocyte competence. As donors were lean (only two with BMI > 30 kg/m2) and young (<34 years old), a possible effect of obesity or advanced age on the CC metabolome could not be determined. WIDER IMPLICATIONS OF THE FINDINGS: The abundance of malonate, 5-oxyproline, and erythronate in CC was significantly higher in COCs ultimately establishing pregnancy, providing clues on the pathways required for oocyte competence. The untargeted analysis uncovered the presence of compounds that were not expected in CC, such as ß-citrylglutamate and the neurotransmitter N-acetyl-aspartyl-glutamate, which may play roles in chromatin remodeling and signaling, respectively. STUDY FUNDING/COMPETING INTEREST(S): Research was supported by the Industrial Doctorate Project IND2017/BIO-7748 funded by Madrid Region Government. The authors declare no competing interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Células do Cúmulo , Oócitos , Feminino , Humanos , Gravidez , Adulto , Células do Cúmulo/metabolismo , Hidroxiprolina/metabolismo , Hidroxiprolina/farmacologia , Oócitos/metabolismo , Oogênese , Malonatos/metabolismo , Malonatos/farmacologia
8.
J Funct Morphol Kinesiol ; 8(3)2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37606408

RESUMO

This study aimed to compare the effects of two 8-week in-season strength-training programs on handball players' physical and technical parameters. Thirty-six male athletes were randomly separated into three groups: a control group (n = 12), a plyometric training group (PG, n = 12), and an eccentric-overload training group (EG, n = 12). The PG and EG performed upper- and lower-limb plyometric or eccentric-overload exercises, respectively, three times per week. Control groups performed regular handball training. The athletes were assessed for counter movement jump (CMJ) and Abalakov vertical jump (ABK) height, 15 m linear sprint time, handball-throwing speed (i.e., penalty throw; 3-step running throw; jump throw), and cardiorespiratory endurance through the 20 m shuttle-run test. Heart rate and blood lactate were measured at the end of the endurance test. No baseline differences were noted for dependent variables between groups. The session rating of perceived exertion was similar between the intervention groups (PG = 361 ± 12.2 AU; EG = 370 ± 13.3 AU). The ANOVA revealed significant (p < 0.05; Δ = 5-9%; effect size (ES) = 0.45-1.96). Similar improvements for experimental groups compared to the control group for CMJ, ABK jump, penalty throw, 3-step running throw, and jump throw. However, interventions did not affect 15 m, cardiorespiratory endurance, nor heart rate or blood lactate after the endurance test. In conclusion, an 8-week handball intervention by performing plyometric or eccentric-overload training in-season improves the physical and technical parameters of male players when compared to regular handball practice.

9.
ACS Nano ; 17(17): 16960-16967, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37410703

RESUMO

The resistance of an ordered 3D-Bi2Te3 nanowire nanonetwork was studied at low temperatures. Below 50 K the increase in resistance was found to be compatible with the Anderson model for localization, considering that conduction takes place in individual parallel channels across the whole sample. Angle-dependent magnetoresistance measurements showed a distinctive weak antilocalization characteristic with a double feature that we could associate with transport along two perpendicular directions, dictated by the spatial arrangement of the nanowires. The coherence length obtained from the Hikami-Larkin-Nagaoka model was about 700 nm across transversal nanowires, which corresponded to approximately 10 nanowire junctions. Along the individual nanowires, the coherence length was greatly reduced to about 100 nm. The observed localization effects could be the reason for the enhancement of the Seebeck coefficient observed in the 3D-Bi2Te3 nanowire nanonetwork compared to individual nanowires.

10.
JACC CardioOncol ; 5(3): 392-401, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37397079

RESUMO

Background: Anthracycline-related cardiomyopathy is a leading cause of premature death in childhood cancer survivors. The high interindividual variability in risk suggests the need to understand the underlying pathogenesis. Objectives: The authors interrogated differentially expressed genes (DEGs) to identify genetic variants serving regulatory functions or genetic variants not easily identified when using genomewide array platforms. Using leads from DEGs, candidate copy number variants (CNVs) and single-nucleotide variants (SNVs) were genotyped. Methods: Messenger RNA sequencing was performed on total RNA from peripheral blood of 40 survivors with cardiomyopathy (cases) and 64 matched survivors without cardiomyopathy (control subjects). Conditional logistic regression analysis adjusting for sex, age at cancer diagnosis, anthracycline dose, and chest radiation was used to assess the associations between gene expression and cardiomyopathy and between CNVs and SNVs and cardiomyopathy. Results: Haptoglobin (HP) was identified as the top DEG. Participants with higher HP gene expression had 6-fold greater odds of developing cardiomyopathy (OR: 6.4; 95% CI: 1.4-28.6). The HP2-specific allele among the HP genotypes (HP1-1, HP1-2, and HP2-2) had higher transcript levels, as did the G allele among SNVs previously reported to be associated with HP gene expression (rs35283911 and rs2000999). The HP1-2 and HP2-2 genotypes combined with the G/G genotype for rs35283911 and/or rs2000999 placed the survivors at 4-fold greater risk (OR: 3.9; 95% CI: 1.0-14.5) for developing cardiomyopathy. Conclusions: These findings provide evidence of a novel association between HP2 allele and cardiomyopathy. HP binds to free hemoglobin to form an HP-hemoglobin complex, thereby preventing oxidative damage from free heme iron, thus providing biological plausibility to the mechanistic basis of the present observation.

11.
J Exp Bot ; 74(19): 6069-6088, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37429579

RESUMO

The plant immune system is constituted of two functionally interdependent branches that provide the plant with an effective defense against microbial pathogens. They can be considered separate since one detects extracellular pathogen-associated molecular patterns by means of receptors on the plant surface, while the other detects pathogen-secreted virulence effectors via intracellular receptors. Plant defense depending on both branches can be effectively suppressed by host-adapted microbial pathogens. In this review we focus on bacterially driven suppression of the latter, known as effector-triggered immunity (ETI) and dependent on diverse NOD-like receptors (NLRs). We examine how some effectors secreted by pathogenic bacteria carrying type III secretion systems can be subject to specific NLR-mediated detection, which can be evaded by the action of additional co-secreted effectors (suppressors), implying that virulence depends on the coordinated action of the whole repertoire of effectors of any given bacterium and their complex epistatic interactions within the plant. We consider how ETI activation can be avoided by using suppressors to directly alter compromised co-secreted effectors, modify plant defense-associated proteins, or occasionally both. We also comment on the potential assembly within the plant cell of multi-protein complexes comprising both bacterial effectors and defense protein targets.


Assuntos
Bactérias , Plantas , Plantas/metabolismo , Bactérias/metabolismo , Proteínas de Plantas/metabolismo , Proteínas NLR , Imunidade Vegetal , Doenças das Plantas/microbiologia , Proteínas de Bactérias/metabolismo
13.
Mol Syst Biol ; 19(1): e11037, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36598022

RESUMO

Interleukin-10 (IL-10) is an anti-inflammatory cytokine that is active as a swapped domain dimer and is used in bacterial therapy of gut inflammation. IL-10 can be used as treatment of a wide range of pulmonary diseases. Here we have developed a non-pathogenic chassis (CV8) of the human lung bacterium Mycoplasma pneumoniae (MPN) to treat lung diseases. We find that IL-10 expression by MPN has a limited impact on the lung inflammatory response in mice. To solve these issues, we rationally designed a single-chain IL-10 (SC-IL10) with or without surface mutations, using our protein design software (ModelX and FoldX). As compared to the IL-10 WT, the designed SC-IL10 molecules increase the effective expression in MPN four-fold, and the activity in mouse and human cell lines between 10 and 60 times, depending on the cell line. The SC-IL10 molecules expressed in the mouse lung by CV8 in vivo have a powerful anti-inflammatory effect on Pseudomonas aeruginosa lung infection. This rational design strategy could be used to other molecules with immunomodulatory properties used in bacterial therapy.


Assuntos
Interleucina-10 , Pneumonia , Camundongos , Humanos , Animais , Interleucina-10/genética , Pulmão , Pneumonia/prevenção & controle , Pneumonia/patologia , Citocinas , Inflamação/patologia , Bactérias , Pseudomonas aeruginosa
14.
J Clin Oncol ; 41(9): 1758-1769, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36508697

RESUMO

PURPOSE: Interindividual variability in the dose-dependent association between anthracyclines and cardiomyopathy suggests a modifying role of genetic susceptibility. Few previous studies have examined gene-anthracycline interactions. We addressed this gap using the Childhood Cancer Survivor Study (discovery) and the Children's Oncology Group (COG) study COG-ALTE03N1 (replication). METHODS: A genome-wide association study (Illumina HumanOmni5Exome Array) in 1,866 anthracycline-exposed Childhood Cancer Survivor Study participants (126 with heart failure) was used to identify single-nucleotide polymorphisms (SNPs) with either main or gene-environment interaction effect on anthracycline-related cardiomyopathy that surpassed a prespecified genome-wide threshold for statistical significance. We attempted replication in a matched case-control set of anthracycline-exposed childhood cancer survivors with (n = 105) and without (n = 160) cardiomyopathy from COG-ALTE03N1. RESULTS: Two SNPs (rs17736312 [ROBO2]) and rs113230990 (near a CCCTC-binding factor insulator [< 750 base pair]) passed the significance cutoff for gene-anthracycline dose interaction in discovery. SNP rs17736312 was successfully replicated. Compared with the GG/AG genotypes on rs17736312 and anthracyclines ≤ 250 mg/m2, the AA genotype and anthracyclines > 250 mg/m2 conferred a 2.2-fold (95% CI, 1.2 to 4.0) higher risk of heart failure in discovery and an 8.2-fold (95% CI, 2.0 to 34.4) higher risk in replication. ROBO2 encodes transmembrane Robo receptors that bind Slit ligands (SLIT). Slit-Robo signaling pathway promotes cardiac fibrosis by interfering with the transforming growth factor-ß1/small mothers against decapentaplegic (Smad) pathway, resulting in disordered remodeling of the extracellular matrix and potentiating heart failure. We found significant gene-level associations with heart failure: main effect (TGF-ß1, P = .007); gene*anthracycline interaction (ROBO2*anthracycline, P = .0003); and gene*gene*anthracycline interaction (SLIT2*TGF-ß1*anthracycline, P = .009). CONCLUSION: These findings suggest that high-dose anthracyclines combined with genetic variants involved in the profibrotic Slit-Robo signaling pathway promote cardiac fibrosis via the transforming growth factor-ß1/Smad pathway, providing credence to the biologic plausibility of the association between SNP rs17736312 (ROBO2) and anthracycline-related cardiomyopathy.


Assuntos
Sobreviventes de Câncer , Cardiomiopatias , Insuficiência Cardíaca , Neoplasias , Criança , Humanos , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/uso terapêutico , Estudo de Associação Genômica Ampla , Antraciclinas/efeitos adversos , Neoplasias/tratamento farmacológico , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/genética , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/genética , Antibióticos Antineoplásicos/uso terapêutico , Fibrose , Receptores Imunológicos/genética , Receptores Imunológicos/uso terapêutico
15.
JACC CardioOncol ; 5(6): 807-818, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38205005

RESUMO

Background: Anthracyclines are highly effective in treating cancer, albeit with increased cardiomyopathy risk. Although risk is attributed to associations with single nucleotide polymorphisms (SNPs), multiple SNPs on a gene and their interactions remain unexamined. Objectives: This study examined gene-level associations with cardiomyopathy among cancer survivors using whole-exome sequencing data. Methods: For discovery, 278 childhood cancer survivors (129 cases; 149 matched control subjects) from the COG (Children's Oncology Group) study ALTE03N1 were included. Logic regression (machine learning) was used to identify gene-level SNP combinations for 7,212 genes and ordinal logistic regression to estimate gene-level associations with cardiomyopathy. Models were adjusted for primary cancer, age at cancer diagnosis, sex, race/ethnicity, cumulative anthracycline dose, chest radiation, cardiovascular risk factors, and 3 principal components. Statistical significance threshold of 6.93 × 10-6 accounted for multiple testing. Three independent cancer survivor populations (COG study, BMTSS [Blood or Marrow Transplant Survivor Study] and CCSS [Childhood Cancer Survivor Study]) were used to replicate gene-level associations and examine SNP-level associations from discovery genes using ordinal logistic, conditional logistic, and Cox regression models, respectively. Results: Median age at cancer diagnosis for discovery cases and control subjects was 6 years and 8 years, respectively. Gene-level association for P2RX7 (OR: 0.10; 95% CI: 0.04-0.27; P = 2.19 × 10-6) was successfully replicated (HR: 0.65; 95% CI: 0.47-0.90; P = 0.009) in the CCSS cohort. Additional signals were identified on TNIK, LRRK2, MEFV, NOBOX, and FBN3. Individual SNPs across all discovery genes, except FBN3, were replicated. Conclusions: In our study, SNP sets having 1 or no copies of P2RX7 variant alleles were associated with reduced risk of cardiomyopathy, presenting a potential therapeutic target to mitigate cardiac outcomes in cancer survivors.

16.
Ultrasound Med Biol ; 48(10): 1995-2008, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35902276

RESUMO

The main techniques used to image the brain and obtain structural data are magnetic resonance imaging and X-ray computed tomography. These techniques produce images with high spatial resolution, but with the disadvantage of requiring very large equipment with special installation needs. In addition, X-ray tomography uses ionizing radiation, which limits their use. Ultrasound imaging is a safe technology that is delivered using compact and mobile devices. However, conventional ultrasound reconstruction techniques have failed to obtain images of the brain because of, fundamentally, the presence of the skull and the distortion that it produces on ultrasound. Recent studies have indicated that full-waveform inversion, a computational technique originally from Earth science, has the potential to generate accurate 3-D images of the brain. This technology can overcome the limitations of conventional ultrasound imaging, but a prototype for transcranial applications does not yet exist. Here, we investigate different designs of an annular array of ultrasound transducers to optimize the number of elements and rotations needed to conduct transcranial imaging with full-waveform inversion. This device uses small-diameter, low-frequency transducers that readily propagate ultrasound through the skull with good signal-to-noise ratios. It also incorporates the use of rotations to produce a high-density coverage of the target and acquire redundant traces that are beneficial for full-waveform inversion. We have built a ring of 40 transducers to illustrate that this design is capable of reconstructing images of the brain, retrieving its anatomy and acoustic properties with millimeter resolution. Laboratory results reveal the ability of this device to successfully image a 2.5-D brain- and skull-mimicking phantom using full-waveform inversion. To our knowledge, this is the first prototype ever used for transcranial-like imaging. The importance of these findings and their implications for the design of a 3-D reconstruction system with possible clinical applications are discussed.


Assuntos
Encéfalo , Transdutores , Desenho de Equipamento , Neuroimagem , Imagens de Fantasmas , Ultrassonografia
17.
Hum Reprod Open ; 2022(3): hoac029, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35864920

RESUMO

STUDY QUESTION: Is relative mitochondrial DNA (mtDNA) content in cumulus cells (CCs) related to embryo developmental competence in humans and/or the bovine model? SUMMARY ANSWER: mtDNA content in CCs provides a poor predictive value of oocyte developmental potential, both in vitro and following embryo transfer. WHAT IS KNOWN ALREADY: CCs are closely connected to the oocyte through transzonal projections, serving essential metabolic functions during folliculogenesis. These oocyte-supporting cells are removed and discarded prior to ICSI, thereby providing interesting biological material on which to perform molecular analyses designed to identify markers that predict oocyte developmental competence. Previous studies have positively associated oocyte mtDNA content with developmental potential in animal models and women. However, it remains debatable whether mtDNA content in CCs could be used as a proxy to infer oocyte developmental potential. STUDY DESIGN SIZE DURATION: mtDNA content was analyzed in CCs obtained from 109 human oocytes unable to develop to blastocyst, able to develop to blastocyst but failing to establish pregnancy or able to develop to blastocyst and to establish pregnancy. mtDNA analysis was also performed on bovine cumulus samples collected from 120 oocytes unable to cleave, oocytes developing into cleaved embryos but arresting development prior to the blastocyst stage or oocytes developing to blastocysts. PARTICIPANTS/MATERIALS SETTING METHODS: Human CCs samples were obtained from women undergoing IVF. Only unfrozen oocytes and embryos not submitted to preimplantation genetic testing were included in the analysis. Bovine samples were obtained from slaughtered cattle and individually matured, fertilized and cultured in vitro. Relative mtDNA was assessed by quantitative PCR analysis. MAIN RESULTS AND THE ROLE OF CHANCE: mtDNA content in human and bovine CCs did not differ according to the developmental potential of their enclosed oocyte. Moreover, mtDNA content in bovine oocytes did not correlate with that of their corresponding CCs. LARGE SCALE DATA: N/A. LIMITATIONS REASONS FOR CAUTION: The lack of correlation found between mtDNA content in human CCs and oocytes was also assessed in bovine samples. Although bovine folliculogenesis, mono-ovulatory ovulation and early embryo development exhibit considerable similarities with that of humans, they may not be fully comparable. WIDER IMPLICATIONS OF THE FINDINGS: The use of molecular markers for oocyte developmental potential in CCs could be used to enhance success rates following single embryo transfer. However, our data indicate that mtDNA in CCs is not a good proxy for oocyte quality. STUDY FUNDING/COMPETING INTERESTS: This research was supported by the Industrial Doctorate Project IND2017/BIO-7748 funded by the Madrid Region Government. The authors declare no competing interests.

18.
Cardiovasc Toxicol ; 22(8): 701-712, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35596909

RESUMO

Cardiac troponin T (encoded by TNNT2) is involved in the contraction of cardiomyocytes during beating. The alternative splicing of TNNT2 results in four transcript variants with differential Ca2+ sensitivity. The splicing of TNNT2 involves phosphorylation of the splicing factor SRSF6 by DYRK1A. Altered TNNT2 splicing patterns have been identified in failing human hearts. There is a paucity of studies describing DYRK1A-SRSF6-TNNT2 interplays in human cardiomyocytes. Also, it is not known whether the sensitivity of cardiomyocytes to cardiotoxic anthracyclines is modified in the context of variable DYRK1A-TNNT2 expression. In this study, we investigated the impact of DYRK1A on the endogenous expression of TNNT2 splicing variants in iPSC-derived cardiomyocytes. We also examined whether DYRK1A expression modifies the sensitivity of cardiomyocytes to the cardiotoxic drug daunorubicin (DAU). DYRK1A over-expression increased the abundance of TNNT2 fetal variants by ~ 58% whereas the abundance of the adult cTnT3 variant decreased by ~ 27%. High DYRK1A expression increased the phosphorylation of SRSF6 by ~ 25-65%. DAU cytotoxicity was similar between cardiomyocytes with variable levels of DYRK1A expression. DYRK1A over-expression ameliorated the impact of DAU on beating frequency. This study lays the foundation to further investigate the contribution of variable DYRK1A-TNNT2 expression to Ca2+ handling and beating in human cardiomyocytes.


Assuntos
Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Adulto , Cardiotoxicidade/metabolismo , Daunorrubicina/metabolismo , Daunorrubicina/toxicidade , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Tirosina Quinases , Fatores de Processamento de Serina-Arginina/metabolismo , Troponina T/genética , Quinases Dyrk
19.
Chem Mater ; 34(24): 10849-10860, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36590704

RESUMO

Finding simple, easily controlled, and flexible synthetic routes for the preparation of ternary and hybrid nanostructured semiconductors is always highly desirable, especially to fulfill the requirements for mass production to enable application to many fields such as optoelectronics, thermoelectricity, and catalysis. Moreover, understanding the underlying reaction mechanisms is equally important, offering a starting point for its extrapolation from one system to another. In this work, we developed a new and more straightforward colloidal synthetic way to form hybrid Au-Ag2X (X = S, Se) nanoparticles under mild conditions through the reaction of Au and Ag2X nanostructured precursors in solution. At the solid-solid interface between metallic domains and the binary chalcogenide domains, a small fraction of a ternary AuAg3X2 phase was observed to have grown as a consequence of a solid-state electrochemical reaction, as confirmed by computational studies. Thus, the formation of stable ternary phases drives the selective hetero-attachment of Au and Ag2X nanoparticles in solution, consolidates the interface between their domains, and stabilizes the whole hybrid Au-Ag2X systems.

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