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1.
Eur Heart J Imaging Methods Pract ; 2(1): qyae009, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39045208

RESUMO

Aims: Recently, novel post-processing tools have become available that measure intraventricular pressure gradients (IVPGs) on routinely obtained long-axis cine cardiac magnetic resonance (CMR) images. IVPGs provide a comprehensive overview of both systolic and diastolic left ventricular (LV) functions. Whether IVPGs are associated with clinical outcome after ST-elevation myocardial infarction (STEMI) is currently unknown. Here, we investigated the association between CMR-derived LV-IVPGs and major adverse cardiovascular events (MACE) in a large reperfused STEMI cohort with long-term outcome. Methods and results: In this prospectively enrolled multi-centre cohort study, 307 patients underwent CMR within 14 days after the first STEMI. LV-IVPGs (from apex-to-base) were estimated on the long-axis cine images. During a median follow-up of 9.7 (5.9-12.5) years, MACE (i.e. composite of cardiovascular death and de novo heart failure hospitalisation) occurred in 49 patients (16.0%). These patients had larger infarcts, more often microvascular injury, and impaired LV-IVPGs. In univariable Cox regression, overall LV-IVPG was significantly associated with MACE and remained significantly associated after adjustment for common clinical risk factors (hazard ratio (HR) 0.873, 95% confidence interval (CI) 0.794-0.961, P = 0.005) and myocardial injury parameters (HR 0.906, 95% CI 0.825-0.995, P = 0.038). However, adjusted for LV ejection fraction and LV global longitudinal strain (GLS), overall LV-IVPG does not provide additional prognostic information (HR 0.959, 95% CI 0.866-1.063, P = 0.426). Conclusion: Early after STEMI, CMR-derived LV-IVPGs are univariably associated with MACE and this association remains significant after adjustment for common clinical risk factors and measures of infarct severity. However, LV-IVPGs do not add prognostic value to LV ejection fraction and LV GLS.

2.
Proc Natl Acad Sci U S A ; 121(28): e2400737121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38968127

RESUMO

In recent years, the exploration of genome three-dimensional (3D) conformation has yielded profound insights into the regulation of gene expression and cellular functions in both animals and plants. While animals exhibit a characteristic genome topology defined by topologically associating domains (TADs), plants display similar features with a more diverse conformation across species. Employing advanced high-throughput sequencing and microscopy techniques, we investigated the landscape of 26 histone modifications and RNA polymerase II distribution in tomato (Solanum lycopersicum). Our study unveiled a rich and nuanced epigenetic landscape, shedding light on distinct chromatin states associated with heterochromatin formation and gene silencing. Moreover, we elucidated the intricate interplay between these chromatin states and the overall topology of the genome. Employing a genetic approach, we delved into the role of the histone modification H3K9ac in genome topology. Notably, our investigation revealed that the ectopic deposition of this chromatin mark triggered a reorganization of the 3D chromatin structure, defining different TAD-like borders. Our work emphasizes the critical role of H3K9ac in shaping the topology of the tomato genome, providing valuable insights into the epigenetic landscape of this agriculturally significant crop species.


Assuntos
Epigenoma , Histonas , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Histonas/metabolismo , Histonas/genética , Epigênese Genética , Genoma de Planta , Cromatina/metabolismo , Cromatina/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Heterocromatina/metabolismo , Heterocromatina/genética , Código das Histonas/genética
3.
ChemSusChem ; : e202401192, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39049555

RESUMO

The incorporation of hydrophilic and basic sites from phosphotriazaadamantane and saccharine in a water-soluble Pd complex and the subsequent confinement into mesoporous silica support increases the activity and stability of the palladium catalytic species for the room-temperature aqueous hydrogenation of either bicarbonate or CO2 into formic acid. The use of low Pd loadings (<0.1mmolPd·g-1) of the well-dispersed complex on SBA-15 mesoporous silica allows performing the reaction under room temperature, and aqueous conditions, exhibiting TON of ca. 40-100, for the CO2 or bicarbonate hydrogenation, respectively, which is one order of magnitude higher than the homogeneous case, allowing the easy isolation and recycling of the solid catalyst.

4.
Child Abuse Negl ; 154: 106941, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39024783

RESUMO

BACKGROUND: The Childhood Trauma Questionnaire- Short Form (CTQ-SF) is among the most extensively studied and widely utilized instruments for evaluating childhood maltreatment. OBJECTIVE: The purpose of this study was to conduct a reliability generalization meta-analysis to estimate the average reliability of the CTQ-SF scores and its factors and search for study characteristics that can explain the variability in those coefficients. METHODS: A total of 39 independent samples provided 243 reliability estimates (Cronbach's alpha, McDonald's omega, and/or test-retest reliability coefficients) with the data at hand for the scores on the CTQ-SF and its five subscales for this meta-analysis. RESULTS: Random and mixed-effects models were employed for analyzing the data. The average Cronbach's alpha coefficient for the CTQ-SF total score was 0.891 (95 % CI: 0.868, 0.910). For the subscales, the average Cronbach's alpha coefficient ranged from 0.656 (Physical Neglect) to 0.916 (Sexual Abuse). The average McDonald's Omega coefficient for the CTQ-SF total score was 0.800 (95 % CI: 0.800 0.800). For the subscales, the average McDonald's Omega ranged from 0.740 (Physical Neglect) to 0.900 (Sexual Abuse). The average test-retest reliability for CTQ-SF total score was 0.788 (95 % CI: 0.635, 0.872), with the subscales ranging from 0.668 (Physical Neglect) to 0.709 (Physical Abuse). Moderator analyses revealed that some factors can affect reliability estimate. CONCLUSIONS: Although CTQ-SF and its five subscales have shown adequate reliability, it may vary as a function of the variability of scores, geographical location, financial source, and the affiliation of the main researcher.

5.
Int J Mol Sci ; 25(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39000332

RESUMO

Fasciolosis, a globally re-emerging zoonotic disease, is mostly caused by the parasitic infection with Fasciola hepatica, often known as the liver fluke. This disease has a considerable impact on livestock productivity. This study aimed to evaluate the fluke burdens and faecal egg counts in goats that were administered phage clones of cathepsin L mimotopes and then infected with F. hepatica metacercariae. Additionally, the impact of vaccination on the histology of the reproductive system, specifically related to egg generation in adult parasites, was examined. A total of twenty-four goats, which were raised in sheds, were divided into four groups consisting of six animals each. These groups were randomly assigned. The goats were then subjected to two rounds of vaccination. Each vaccination involved the administration of 1 × 1013 phage particles containing specific mimotopes for cathepsin L2 (group 1: PPIRNGK), cathepsin L1 (group 2: DPWWLKQ), and cathepsin L1 (group 3: SGTFLFS). The immunisations were carried out on weeks 0 and 4, and the Quil A adjuvant was used in combination with the mimotopes. The control group was administered phosphate-buffered saline (PBS) (group 4). At week 6, all groups were orally infected with 200 metacercariae of F. hepatica. At week 22 following the initial immunisation, the subjects were euthanised, and adult F. hepatica specimens were retrieved from the bile ducts and liver tissue, and subsequently quantified. The specimens underwent whole-mount histology for the examination of the reproductive system, including the testis, ovary, vitellaria, Mehlis' gland, and uterus. The mean fluke burdens following the challenge were seen to decrease by 50.4%, 62.2%, and 75.3% (p < 0.05) in goats that received vaccinations containing cathepsin L2 PPIRNGK, cathepsin L1 DPWWLKQ, and cathepsin L1 SGTFLFS, respectively. Animals that received vaccination exhibited a significant reduction in the production of parasite eggs. The levels of IgG1 and IgG2 isotypes in vaccinated goats were significantly higher than in the control group, indicating that protection is associated with the induction of a mixed Th1/Th2 immune response. The administration of cathepsin L to goats exhibits a modest level of efficacy in inducing histological impairment in the reproductive organs of liver flukes, resulting in a reduction in egg output.


Assuntos
Catepsina L , Fasciola hepatica , Fasciolíase , Cabras , Vacinação , Animais , Fasciola hepatica/imunologia , Catepsina L/metabolismo , Fasciolíase/veterinária , Fasciolíase/prevenção & controle , Fasciolíase/imunologia , Fasciolíase/parasitologia , Vacinação/métodos , Feminino , Masculino , Doenças das Cabras/parasitologia , Doenças das Cabras/prevenção & controle , Doenças das Cabras/imunologia , Contagem de Ovos de Parasitas , Bacteriófagos/imunologia
6.
Sensors (Basel) ; 24(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39000994

RESUMO

This study rigorously investigates the effectiveness of nonlinear filters in CMOS for 2-D signal processing to enhance image quality. We comprehensively compare traditional linear filters' performance, which operate on the principle of linearity, with nonlinear filters, such as the median-median (Med-Med) approach, designed to handle nonlinear data. To ensure the validity of our findings, we use widely accepted metrics like normalized squared error (NSE), peak signal-to-noise ratio (PSNR), and structural similarity index (SSIM) to quantify the differences. Our simulations and experiments, conducted under controlled conditions, demonstrate that nonlinear filters in CMOS outperform linear filters in removing impulse noise and enhancing images. We also address the challenges of implementing these algorithms at the hardware level, focusing on power consumption and chip area optimization. Additionally, we propose a new architecture for the Med-Med filter and validate its functionality through experiments using a 9-pixel image sensor array. Our findings highlight the potential of nonlinear filters in CMOS for real-time image quality enhancement and their applicability in various real-world imaging applications. This research contributes to visual technology by combining theoretical insights with practical implementations, paving the way for more efficient and adaptable imaging systems.

7.
Physiol Plant ; 176(4): e14388, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38946634

RESUMO

Plants can experience a variety of environmental stresses that significantly impact their fitness and survival. Additionally, biotic stress can harm agriculture, leading to reduced crop yields and economic losses worldwide. As a result, plants have developed defense strategies to combat potential invaders. These strategies involve regulating redox homeostasis. Several studies have documented the positive role of plant antioxidants, including Ascorbate (Asc), under biotic stress conditions. Asc is a multifaceted antioxidant that scavenges ROS, acts as a co-factor for different enzymes, regulates gene expression, and facilitates iron transport. However, little attention has been given to Asc and its transport, regulatory effects, interplay with phytohormones, and involvement in defense processes under biotic stress. Asc interacts with other components of the redox system and phytohormones to activate various defense responses that reduce the growth of plant pathogens and promote plant growth and development under biotic stress conditions. Scientific reports indicate that Asc can significantly contribute to plant resistance against biotic stress through mutual interactions with components of the redox and hormonal systems. This review focuses on the role of Asc in enhancing plant resistance against pathogens. Further research is necessary to gain a more comprehensive understanding of the molecular and cellular regulatory processes involved.


Assuntos
Ácido Ascórbico , Reguladores de Crescimento de Plantas , Plantas , Estresse Fisiológico , Reguladores de Crescimento de Plantas/metabolismo , Ácido Ascórbico/metabolismo , Plantas/metabolismo , Plantas/imunologia , Antioxidantes/metabolismo , Oxirredução , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia
8.
Haematologica ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38988266

RESUMO

The value of quantitative immunoprecipitation mass spectrometry (QIP-MS) to identify the M-protein is being investigated in patients with monoclonal gammopathies but no data are yet available in high-risk smoldering myeloma (HRsMM). We have therefore investigated QIP-MS to monitor peripheral residual disease (PRD) in 62 HRsMM patients enrolled in the GEM-CESAR trial. After 24 cycles of maintenance, detecting the M-protein by MS or clonal plasma cells by NGF identified cases with a significantly shorter median PFS (mPFS; MS: not reached vs 1,4 years, p=0.001; NGF: not reached vs 2 years, p=0.0002) but reaching CR+sCR did not discriminate patients with different outcome. With NGF as a reference, the combined results of NGF and MS showed a high negative predictive value (NPV) of MS: 81% overall and 73% at treatment completion. When sequential results were considered, sustained negativity by MS or NGF was associated with a very favorable outcome with a mPFS not yet reached vs 1.66 years and 2.18 years in cases never attaining PRD or minimal residual disease (MRD) negativity, respectively. We can thus conclude that 1) the standard response categories of the IMWG do not seem to be useful for treatment monitoring in HRsMM patients, 2) MS could be used as a non-invasive, clinical valuable tool with the capacity of guiding timely bone marrow evaluations (based on its high NPV with NGF as a reference) and 3) similarly to NGF, sequential results of MS are able identify a subgroup of HRsMM patients with long-term disease control. This study was registered at www.clinicaltrials.gov (ClinicalTrials.gov identifier: NCT02415413).

9.
J Clin Med ; 13(13)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38999434

RESUMO

Objective: The goal of this study is to validate the psychometric properties of the Modified Dental Anxiety Scale (MDAS) and the Dental Fear Scale (DFS) at three different times: seven days before, immediately after, and seven days after watching a video of surgical extraction of a lower third molar in a sample with four strata: anxiety disorder, adjustment disorder, mixed anxiety-depressive disorder, and no mental disorder ages 18-70 in a psychiatric clinic in Malaga. Methods: The Research Ethics Committee of the Virgen Macarena-Virgen del Rocío Hospitals approved the study. After being interviewed by a psychiatrist and subsequently completing the Hamilton Rating Scales for Anxiety and Depression, the participants were divided into 4 strata (60 persons in each). The influence of education level was then analyzed. Results: The scales demonstrated good psychometric properties, with higher MDAS and DFS scores for lower levels of education and mixed anxiety-depressive disorder. Conclusions: Patients who show higher levels of dental anxiety and dental fear will be those with lower education levels, as well as those who suffer from mixed anxiety-depressive disorder.

10.
Plants (Basel) ; 13(13)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38999574

RESUMO

In the Mexican Caribbean, environmental changes, hydrometeorological events, and anthropogenic activities promote dynamism in the coastal vegetation cover associated with the dune; however, their pace and magnitude remain uncertain. Using Landsat 7 imagery, spatial and temporal changes in coastal dune vegetation were estimated for the 2011-2020 period in the Sian Ka'an Biosphere Reserve. The SAVI index revealed cover changes at different magnitudes and paces at the biannual, seasonal, and monthly timeframes. Climatic seasons had a significant influence on vegetation cover, with increases in cover during northerlies (SAVI: p = 0.000), while the topographic profile of the dune was relevant for structure. Distance-based multiple regressions and redundancy analysis showed that temperature had a significant effect (p < 0.05) on SAVI patterns, whereas precipitation showed little influence (p > 0.05). The Mann-Kendall tendency test indicated high dynamism in vegetation loss and recovery with no defined patterns, mostly associated with anthropogenic disturbance. High-density vegetation such as mangroves, palm trees, and shrubs was the most drastically affected, although a reduction in bare soil was also recorded. This study demonstrated that hydrometeorological events and climate variability in the long term have little influence on vegetation dynamism. Lastly, it was observed that anthropogenic activities promoted vegetation loss and transitions; however, the latter were also linked to recoveries in areas with pristine environments, relevant for tourism.

11.
BMC Nurs ; 23(1): 477, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010065

RESUMO

OBJECTIVES: The aim of this study was to describe grandmothers' experiences of taking care of their grandchildren in terms of their care-giving tasks, motivations and emotions. METHODS: A qualitative phenomenological study was conducted. Purposive sampling was used, based on the relevance of the research question. Seventeen participants were included, women ≥ 65 years old, grandmothers who care for their grandchildren at least 10 h per week and who attended the Nursing units of the Primary Care Health Centers (Madrid Public Health Service). Seventeen in-depth interviews were conducted. The interviews were audio-recorded, transcribed verbatim and thematic analysis was carried out from the perspective of hermeneutic phenomenology. For the analysis, the Excel program was used to organize and share the coding process. Also, we followed COREQ guidelines. RESULTS: Four main themes were identified: (a) Care out of obligation, where participants feel an obligation to help their children by caring for grandchildren, regardless of their number, and prefer to do so voluntarily; (b) Care out of responsibility, where grandmothers see their role as a responsibility that includes saving costs by caring for grandchildren and facilitating their children's work life balance; (c) Care as a social duty, reflecting a moral commitment inherited from their mothers to help future generations; and (d) Construction of care from a gender perspective, where grandmothers, as women, primarily assume the care and upbringing of grandchildren. DISCUSSION: Our results contribute to increase knowledge about childcare provided by grandmothers to their grandchildren. Grandmothers become fundamental pillars of families by helping their children balance family and work. Behind this care there is a strong sense of obligation, duty and generational responsibility. Grandmothers' help presents differences in the distribution of tasks and care by sex. Identifying factors that motivate grandmothers to care for their grandchildren helps nurses to perform higher quality comprehensive care.

12.
J Biotechnol ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39032699

RESUMO

Interleukin-2 (IL-2) has been used in cancer treatment for over 30 years. However, due to its high toxicity, new mutant variants have been developed. These variants retain some of the biological properties of the original molecule but offer other therapeutic advantages. At the Center of Molecular Immunology, the IL-2 no-alpha mutein, an IL-2 agonist with lower toxicity than wtIL-2, has been designed, produced, and is currently being evaluated in a Phase I/II clinical trial. The mutein is produced in E. coli as an insoluble material that must be refolded in vitro to yield a fully active protein. Controlled oxidation steps are essential in the purification process of recombinant proteins produced in E. coli to ensure the proper formation of the disulfide bonds in the molecules. In this case, the new purification process includes a copper-catalyzed air oxidation step to induce disulfide bond establishment. The optimal conditions of pH, copper, protein and detergent concentration for this step were determined through screening. The produced protein demonstrated a conserved 3D structure, higher purity, and greater biological activity than the obtained by established process without the oxidation step. Four batches were produced and evaluated, demonstrating the consistency of the new process.

14.
Scand J Psychol ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38824420

RESUMO

INTRODUCTION: This study explores how empowering human resource management (HRM) practices based on structural empowerment (access to opportunities, resources, support, and information) affect both personal initiative and job satisfaction of service employees through individual-level factors (psychological empowerment). METHODS: We conducted a cross-sectional survey study and collected 439 valid responses from service employees in Spain. The hypotheses were tested using structural equation modeling (SEM) with confidence intervals based on 10,000 resamples (i.e., bootstrapping technique). RESULTS: Our results showed that psychological empowerment partially mediated the relationship between structural empowerment and job satisfaction. It also fully mediated the relationship between structural empowerment and personal initiative at work. CONCLUSION: These findings emphasize the importance of HRM practices that can empower employees as key determinants of job satisfaction and personal initiative at service companies. Furthermore, a structural empowerment approach is a valid theoretical framework for studying and understanding employees' affective evaluations of work and, more specifically, their personal initiative.

15.
Polymers (Basel) ; 16(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38891480

RESUMO

BACKGROUND: Sealing the peri-implant tissue is a determining factor for long-term implant survival. In the transmucosal region, the cervical fraction of the prosthetic crown is in contact with these tissues, so mucointegration will also be influenced by the biomaterial used for the prosthetic restoration. This study aims to compare the tissue response generated by definitive restorative materials and polymeric materials from a histological point of view. METHODS: This study performed an observational prospective cohort study in which biopsies of the peri-implant mucosa were taken after placement of implant-supported prosthetic restorations made of different materials (zirconium oxide, lithium disilicate, and PMMA). RESULTS: A statistically significant difference was observed in the increase in the thickness of the non-keratinized epithelium when comparing the definitive materials (zirconium oxide/lithium disilicate) vs. the provisional material (PMMA) and in the number of collagen fibers when comparing zirconium oxide and lithium disilicate. CONCLUSIONS: This study found that zirconia is the material that presents the most adequate biological response of peri-implant tissues. It shows a lower intensity of inflammatory cellular content, a total normality in the number of collagen fibers (the arrangement of the fibers is normal in 90% of the cases), and vascular proliferation of connective tissue in 83% of the cases. These parameters make it a material with a predictable response. Similarly, only the following slight statistically significant differences between the definitive and provisional materials are observed, indicating that the biological response generated by the provisional material (PMMA) is not very different from that obtained with the placement of the definitive restoration.

16.
J Clin Med ; 13(11)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38893029

RESUMO

Introduction: This report investigates late-stage internal derangement (ID) of the temporomandibular joint (TMJ) with the aim of establishing a more effective and personalized treatment protocol to improve patients' quality of life (QoL). Material and methods: A consensus was reached among maxillofacial surgeons specializing in LSID, based on a literature research and collective expert experience following the Delphi method. Consensus was considered to be achieved when a response received at least 80% of votes. Results: Four expert groups were established, respectively, focusing on diagnosis, minimally invasive surgery (MIS), open surgery and joint replacement. A comprehensive approach to late-stage ID of the TMJ requires a consensus report. This underscores the need for a personalized treatment plan, considering the variability in clinical presentations and progression of this pathology. Our recommendations aim to optimize clinical outcomes and enhance patient QoL.

17.
Schizophr Res ; 270: 260-272, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38944972

RESUMO

BACKGROUND: It is known that the immune system is dysregulated in schizophrenia, having a state similar to chronic neuroinflammation. The origin of this process is unknown, but it is known that T and B lymphocytes, which are components of the adaptive immune system, play an important role in the pathogenic mechanisms of schizophrenia. METHODS: We analysed the membrane of PBMCs from patients diagnosed with schizophrenia through proteomic analysis (n = 5 schizophrenia and n = 5 control). We found the presence of the Kv1.3 voltage-gated potassium channel and its auxiliary subunit ß1 (KCNAB1) and ß2 (KCNAB2). From a sample of 90 participants, we carried out a study on lymphocytes with whole-cell patch-clamp experiments (n = 7 schizophrenia and n = 5 control), western blot (n = 40 schizophrenia and n = 40 control) and confocal microscopy to evaluate the presence and function of different channels. Kv in both cells. RESULTS: We demonstrated the overexpression of Kv1.1, Kv1.2, Kv1.3, Kv1.6, Kv4.2, Kv4.3 and Kv7.2 channels in PBMCs from patients with schizophrenia. This study represents a groundbreaking exploration, as it involves an electrophysiological analysis performed on T and B lymphocytes from patients diagnosed of schizophrenia compared to healthy participants. We observed that B lymphocytes exhibited an increase in output current along with greater peak current amplitude and voltage conductance curves among patients with schizophrenia compared with healthy controls. CONCLUSIONS: This study showed the importance of the B lymphocyte in schizophrenia. We know that the immune system is altered in schizophrenia, but the physiological mechanisms of this system are not very well known. We suggest that the B lymphocyte may be relevant in the pathophysiology of schizophrenia and that it should be investigated in more depth, opening a new field of knowledge and possibilities for new treatments combining antipsychotics and immunomodulators. The limitation is that all participants received antipsychotic medication, which may have influenced the differences observed between patients and controls. This implies that more studies need to be done where the groups can be separated according to the antipsychotic drug.

18.
Nucleic Acids Res ; 52(13): 7761-7779, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38850156

RESUMO

Alu elements are non-autonomous Short INterspersed Elements (SINEs) derived from the 7SL RNA gene that are present at over one million copies in human genomic DNA. Alu mobilizes by a mechanism known as retrotransposition, which requires the Long INterspersed Element-1 (LINE-1) ORF2-encoded protein (ORF2p). Here, we demonstrate that HeLa strains differ in their capacity to support Alu retrotransposition. Human Alu elements retrotranspose efficiently in HeLa-HA and HeLa-CCL2 (Alu-permissive) strains, but not in HeLa-JVM or HeLa-H1 (Alu-nonpermissive) strains. A similar pattern of retrotransposition was observed for other 7SL RNA-derived SINEs and tRNA-derived SINEs. In contrast, mammalian LINE-1s, a zebrafish LINE, a human SINE-VNTR-Alu (SVA) element, and an L1 ORF1-containing mRNA can retrotranspose in all four HeLa strains. Using an in vitro reverse transcriptase-based assay, we show that Alu RNAs associate with ORF2p and are converted into cDNAs in both Alu-permissive and Alu-nonpermissive HeLa strains, suggesting that 7SL- and tRNA-derived SINEs use strategies to 'hijack' L1 ORF2p that are distinct from those used by SVA elements and ORF1-containing mRNAs. These data further suggest ORF2p associates with the Alu RNA poly(A) tract in both Alu-permissive and Alu-nonpermissive HeLa strains, but that Alu retrotransposition is blocked after this critical step in Alu-nonpermissive HeLa strains.


Assuntos
Elementos Alu , Elementos Nucleotídeos Longos e Dispersos , Humanos , Células HeLa , Elementos Alu/genética , Elementos Nucleotídeos Longos e Dispersos/genética , Elementos Nucleotídeos Curtos e Dispersos/genética , Animais , Retroelementos/genética , RNA/genética , RNA/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , Peixe-Zebra/genética
19.
Animals (Basel) ; 14(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38929451

RESUMO

Fasciolosis is an important economic disease of livestock. There is a global interest in the development of protective vaccines since the current anthelmintic therapy is no longer sustainable. A better knowledge of the host-parasite interaction is needed to design effective vaccines. To date, few studies have evaluated host-parasite interaction by comparing infected and reinfected animals. The present study evaluates the microscopical hepatic lesions in sheep infected and reinfected with Fasciola hepatica during the acute and chronic stages of infection. The histopathological study revealed the presence of necrotizing foci (NF1) associated with larvae migration during the early stages of infection in the primoinfected (PI) and reinfected (RI) groups. In the late stages of infection of the PI group and at the early and late stages of infection in the RI groups, extensive necrotizing/hemorrhagic foci (NF2) were found in the vicinity of enlarged bile ducts, some containing adult flukes, suggesting parasites may have caused NF2 while feeding. The immunohistochemical study revealed an increase in Foxp3+ T cells in both PI and RI groups with respect to the UC group and in the infiltrates adjacent to NF1 in the RI groups with respect to the PI group, suggesting the F. hepatica induce Foxp3 T cell expansion to facilitate parasite survival. In addition, in both the PI and RI groups, and during acute and chronic stages of the infection, a poor expression of iNOS was found accompanied by a strong expression of CD163, suggesting a marked M2 activation of macrophages in the hepatic lesions, which may be related with healing processes, and it also may facilitate parasite survival. The main differences between PI and RI animals were the more severe infiltration of eosinophils and Foxp3+ T cells, whereas RI did not modify M2 activation of macrophages which occurs since the early stages of primoinfection.

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