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1.
Cells ; 12(24)2023 12 08.
Article in English | MEDLINE | ID: mdl-38132118

ABSTRACT

Regulator of TElomere Length Helicase 1 (RTEL1) is a helicase required for telomere maintenance and genome replication and repair. RTEL1 has been previously shown to participate in the nuclear export of small nuclear RNAs. Here we show that RTEL1 deficiency leads to a nuclear envelope destabilization exclusively in cells entering S-phase and in direct connection to origin firing. We discovered that inhibiting protein import also leads to similar, albeit non-cell cycle-related, nuclear envelope disruptions. Remarkably, overexpression of wild-type RTEL1, or of its C-terminal part lacking the helicase domain, protects cells against nuclear envelope anomalies mediated by protein import inhibition. We identified distinct domains in the C-terminus of RTEL1 essential for the interaction with KPNB1 (importin ß) and NUP153, respectively, and we demonstrated that, on its own, the latter domain can promote the dynamic nuclear internalization of peptides that freely diffuse through the nuclear pore. Consistent with putative functions exerted in protein import, RTEL1 can be visualized on both sides of the nuclear pore using high-resolution microscopy. In all, our work points to an unanticipated, helicase-independent, role of RTEL1 in connecting both nucleocytoplasmic trafficking and nuclear envelope integrity to genome replication initiation in S-phase.


Subject(s)
Nuclear Envelope , beta Karyopherins , Humans , Active Transport, Cell Nucleus , Nuclear Envelope/metabolism , beta Karyopherins/metabolism , Nuclear Pore Complex Proteins/metabolism , DNA Replication , DNA Helicases/metabolism
2.
Blood Adv ; 7(22): 7067-7078, 2023 11 28.
Article in English | MEDLINE | ID: mdl-37773887

ABSTRACT

TERRA (telomeric repeat-containing RNA) is a class of long noncoding RNAs transcribed from subtelomeric and telomeric regions. TERRA binds to the subtelomeric and telomeric DNA-forming R-loops (DNA-RNA hybrids), which are involved in telomere maintenance and telomerase function, but the role of TERRA in human cells is not well characterized. Here, we comprehensively investigated for the first time TERRA expression in primary human hematopoietic cells from an exploratory cohort of patients with acute myeloid leukemia (AML), patients with acute lymphoblastic leukemia (ALL), patients with telomere biology disorder (TBD), and healthy subjects. TERRA expression was repressed in primary human hematopoietic cells, including healthy donors, patients with ALL, and patients with TBD, irrespective of their telomere length, except for AML. A second cohort comprising 88 patients with AML showed that TERRA was overexpressed in an AML subgroup also characterized by higher R-loop formation, low TERT and RNAseH2 expression, and a paucity of somatic splicing factor mutations. Telomere length did not correlate with TERRA expression levels. To assess the role of TERRA R-loops in AML, we induced R-loop depletion by increasing RNAseH1 expression in 2 AML cell lines. Decreased TERRA R-loops in AML cell lines resulted in increased chemosensitivity to cytarabine. Our findings indicate that TERRA is uniformly repressed in primary human hematopoietic cells but abnormally expressed in an AML subset with low telomerase.


Subject(s)
Leukemia, Myeloid, Acute , Precursor Cell Lymphoblastic Leukemia-Lymphoma , RNA, Long Noncoding , Telomerase , Humans , Leukemia, Myeloid, Acute/genetics , Cell Line , DNA
4.
Haematologica ; 108(5): 1300-1312, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36579443

ABSTRACT

Androgens have been reported to elongate telomeres in retrospective and prospective trials with patients with telomeropathies, mainly with bone marrow failure. In our single-arm prospective clinical trial (clinicaltrials gov. Identifier: NCT02055456), 17 patients with short telomeres and/or germline pathogenic variants in telomere biology genes associated with at least one cytopenia and/or radiologic diagnosis of interstitial lung disease were treated with 5 mg/kg of intramuscular nandrolone decanoate every 15 days for 2 years. Ten of 13 evaluable patients (77%) showed telomere elongation at 12 months by flow-fluorescence in situ hybridization (average increase, 0.87 kb; 95% confidence interval: 0.20-1.55 kb; P=0.01). At 24 months, all ten evaluable patients showed telomere elongation (average increase, 0.49 kb; 95% confidence interval: 0.24-1.23 kb; P=0.18). Hematologic response was achieved in eight of 16 patients (50%) with marrow failure at 12 months, and in ten of 16 patients (63%) at 24 months. Seven patients had interstitial lung disease at baseline, and two and three had pulmonary response at 12 and 24 months, respectively. Two patients died due to pulmonary failure during treatment. In the remaining evaluable patients, the pulmonary function remained stable or improved, but showed consistent decline after cessation of treatment. Somatic mutations in myeloid neoplasm-related genes were present in a minority of patients and were mostly stable during drug treatment. The most common adverse events were elevations in liver function test levels in 88%, acne in 59%, and virilization in 59%. No adverse events grade ≥4 was observed. Our findings indicate that nandrolone decanoate elongates telomeres in patients with telomeropathies, which correlated with clinical improvement in some cases and tolerable adverse events.


Subject(s)
Lung Diseases, Interstitial , Humans , In Situ Hybridization, Fluorescence , Nandrolone Decanoate , Prospective Studies , Retrospective Studies , Telomere
5.
J Clin Oncol ; 41(1): 132-142, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36054881

ABSTRACT

PURPOSE: Secondary myeloid neoplasms (sMNs) remain the most serious long-term complications in patients with aplastic anemia (AA) and paroxysmal nocturnal hemoglobinuria (PNH). However, sMNs lack specific predictors, dedicated surveillance measures, and early therapeutic interventions. PATIENTS AND METHODS: We studied a multicenter, retrospective cohort of 1,008 patients (median follow-up 8.6 years) with AA and PNH to assess clinical and molecular determinants of clonal evolution. RESULTS: Although none of the patients transplanted upfront (n = 117) developed clonal complications (either sMN or secondary PNH), the 10-year cumulative incidence of sMN in nontransplanted cases was 11.6%. In severe AA, older age at presentation and lack of response to immunosuppressive therapy were independently associated with increased risk of sMN, whereas untreated patients had the highest risk among nonsevere cases. The elapsed time from AA to sMN was 4.5 years. sMN developed in 94 patients. The 5-year overall survival reached 40% and was independently associated with bone marrow blasts at sMN onset. Myelodysplastic syndrome with high-risk phenotypes, del7/7q, and ASXL1, SETBP1, RUNX1, and RAS pathway gene mutations were the most frequent characteristics. Cross-sectional studies of clonal dynamics from baseline to evolution revealed that PIGA/human leukocyte antigen lesions decreased over time, being replaced by clones with myeloid hits. PIGA and BCOR/L1 mutation carriers had a lower risk of sMN progression, whereas myeloid driver lesions marked the group with a higher risk. CONCLUSION: The risk of sMN in AA is associated with disease severity, lack of response to treatment, and patients' age. sMNs display high-risk morphological, karyotypic, and molecular features. The landscape of acquired somatic mutations is complex and incompletely understood and should be considered with caution in medical management.


Subject(s)
Anemia, Aplastic , Hemoglobinuria, Paroxysmal , Humans , Anemia, Aplastic/genetics , Anemia, Aplastic/pathology , Anemia, Aplastic/therapy , Hemoglobinuria, Paroxysmal/genetics , Retrospective Studies , Cross-Sectional Studies , Clonal Evolution/genetics
6.
Clin Neuropsychiatry ; 19(2): 114-120, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35601244

ABSTRACT

Objective: The population's adhesion to measures to ensure social distancing represents a great management challenge in a pandemic context. Despite of evidence shown that social distancing is effective, lack of adherence still persists in many countries. Therefore, it is challenging to separate the effectiveness of government measures, from social distancing driven by personal initiatives. Theory: It is possible that the output of protective behaviors, such as adherence to protective measures and staying in social isolation, is influenced by individual characteristics, such as personality traits or symptoms of mental distress of anxiogenic nature. We hypothesized that individuals with more expressive symptoms of fear or anxiety would have a more protective behavioral tendency in terms of risk exposure, leaving less home during the pandemic. In contrast, individuals with greater emotional stability, as they feel more secure and with a lower perception of risk, could go out more often. Method: A total of 2709 individuals from all regions of Brazil participated in the study (mean age = 42 years; 2134 women). Correlation analysis was performed to investigate the relationships between personality traits according to the big five model and Psychopathological Symptoms (BSI). Then, correlation analysis was performed to investigate how people that go out often differ from people that stay at home, in both symptoms and personality traits. Finally, to investigate the predictors for going out usually, we use multiple regression analysis, using gender, marital status, level of education, and personality traits. Results: During the second wave of COVID-19 in Brazil, individuals with higher emotional stability tended to leave home more than those with more expressive levels of anxiogenic dysregulation. These results reinforce the role of both personality traits and psychopathological symptoms in prophylactic behavior during COVID-19 pandemics. Conclusions: Individuals with greater emotional stability were more likely to leave home during the second wave of COVID-19 than those with higher levels of anxiogenic dysregulation.

7.
J Clin Psychol ; 78(2): 249-265, 2022 02.
Article in English | MEDLINE | ID: mdl-34252980

ABSTRACT

OBJECTIVE: We investigated and validated the presence of emotion regulation profiles in an adult sample. METHOD: In a cross-sectional study, 1165 individuals completed the Emotion Regulation Questionnaire (ERQ), Difficulties in Emotion Regulation Scale (DERS), Positive and Negative Affect Scale (PANAS), and Following Affective States Test (FAST). Sample was divided into three to establish and validate emotion regulation profiles using a latent profile analysis. RESULTS: Sample 1 (n = 375) showed three different profiles: dysregulated, adapted, and unaware regulator. Sample 2 (n = 390) shows a consistent pattern with the same number of profiles that remained stable over time. In Sample 3 (n = 400), we validate and find that cognitive reappraisal and lack of awareness were essential to differentiating profiles. CONCLUSIONS: Three emotional regulation profiles differ due to the levels of positive/negative affect and the propensity to avoid/follow emotions, increasing the understanding of how different regulatory strategies interact and explain different outcomes with mental health.


Subject(s)
Emotional Regulation , Adult , Cross-Sectional Studies , Emotions , Humans , Surveys and Questionnaires
9.
Forensic Sci Int ; 240: 69-79, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24814331

ABSTRACT

Gunshot residues (GSR) from a total of nine different caliber ammunitions produced in Brazil were analyzed and characterized by transmission (TEM) and scanning electron microscopy (SEM). GSR particles are composed of spherical particles of several micrometers of diameter containing distinct amounts of lead, barium and antimony, along with other organic and inorganic elements arising from the primer, gunpowder, the gun and the bullet itself. This study was carried out to obtain additional information on the properties of GSR nanoparticles originated from different types of regular ammunition produced in Brazil by CBC. Besides the SEM, we have used a TEM, exploring its high magnification capability and ability to explore internal structure and chemical composition of submicron particles. We observed that CBC ammunition generated smaller particles than usually reported for other ammunitions and that the three component particles are not a majority. TEM analysis revealed that GSR are partially composed of sub-micron particles as well. The electron diffraction pattern from these particles confirmed them to be mainly composed of lead oxides crystalline nanoparticles that may be agglomerated into larger particles. Energy dispersive X-ray spectroscopy revealed that most of them were composed of two elements, especially PbSb. Ba was not a common element found in the nanoparticles.

10.
Forensic Sci Int ; 177(1): e9-17, 2008 May 02.
Article in English | MEDLINE | ID: mdl-17764860

ABSTRACT

The exposition to heavy metal-rich airborne due to fire practicing has forced to the development of heavy metal-free environmental ammunition primers all over the world. Here we characterize the GSR elements present in the Brazilian lead-free ammunition produced by Companhia Brasileira de Cartuchos (CBC) and commercialized by MagTech in the U.S. and Europe under the name CleanRange centerfire cartridges. Both first and second generations of CleanRange in calibers 9 mm Luger, .40 S&W, .380 AUTO and .38 SPL were analyzed and compared to regular Brazilian CBC ammunition by scanning electron microscopy/energy dispersive spectroscopy. Differences in composition and morphology of GSR particles from the two generations of CleanRange were observed. The first generation ammunition (found in Europe) presented spherical particles, being strontium the only unique element detected. The second generation (found in the U.S.) produced irregular particles composed mostly by potassium, aluminum, silicon and calcium. We can conclude that identification of GSR derived from CBC second generation lead-free ammunition in suspects' hands may be impossible without the addition of a distinct metallic taggant in the primer composition by the manufacturer.

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