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2.
Cancer Med ; 13(8): e7172, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38651186

RESUMO

BACKGROUND: Quantitative measurement of minimal residual disease (MRD) is the "gold standard" for estimating the response to therapy in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Nevertheless, the speed of the MRD response differs for different cytogenetic subgroups. Here we present results of MRD measurement in children with BCP-ALL, in terms of genetic subgroups with relation to clinically defined risk groups. METHODS: A total of 485 children with non-high-risk BCP-ALL with available cytogenetic data and MRD studied at the end-of-induction (EOI) by multicolor flow cytometry (MFC) were included. All patients were treated with standard-risk (SR) of intermediate-risk (ImR) regimens of "ALL-MB 2008" reduced-intensity protocol. RESULTS AND DISCUSSION: Among all study group patients, 203 were found to have low-risk cytogenetics (ETV6::RUNX1 or high hyperdiploidy), while remaining 282 children were classified in intermediate cytogenetic risk group. For the patients with favorable and intermediate risk cytogenetics, the most significant thresholds for MFC-MRD values were different: 0.03% and 0.04% respectively. Nevertheless, the most meaningful thresholds were different for clinically defined SR and ImR groups. For the SR group, irrespective to presence/absence of favorable genetic lesions, MFC-MRD threshold of 0.1% was the most clinically valuable, although for ImR group the most informative thresholds were different in patients from low-(0.03%) and intermediate (0.01%) cytogenetic risk groups. CONCLUSION: Our data show that combining clinical risk factors with MFC-MRD measurement is the most useful tool for risk group stratification of children with BCP-ALL in the reduced-intensity protocols. However, this algorithm can be supplemented with cytogenetic data for part of the ImR group.


Assuntos
Citometria de Fluxo , Neoplasia Residual , Humanos , Neoplasia Residual/genética , Criança , Citometria de Fluxo/métodos , Masculino , Feminino , Pré-Escolar , Adolescente , Lactente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Análise Citogenética/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Subunidade alfa 2 de Fator de Ligação ao Core/genética
3.
Am J Clin Pathol ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38513276

RESUMO

OBJECTIVES: Mixed-phenotype acute leukemia (MPAL) is a rare disease associated with difficulties in the correct lineage assignment of leukemic cells. One of the least common subtypes within this category is characterized by the simultaneous presence of B- and T-lineage-defining antigens. Each case of suspected B/T MPAL should be considered in light of all available laboratory and clinical data to avoid misdiagnosis. METHODS: In this study, we describe 6 pediatric patients who presented with leukemic blasts bearing B- and T-lineage antigens at diagnosis, including their clinical, immunophenotypic, morphologic, and cytogenetic characteristics. RESULTS: In 3 patients, more or less distinct populations of B- and T-lymphoid origin were found; the other 3 patients had a single mixed-phenotype blast population. All cases fulfilled the World Health Organization criteria, but not all of them turned out to be bona fide cases of B/T MPAL according to the available clinical and laboratory data. Found genetic lesions were helpful for the confirmation of MPAL instead of 2 concomitant tumors, but for a general B/T MPAL diagnosis, genetic studies provided the only descriptive data. CONCLUSIONS: The accurate diagnosis of B/T MPAL requires a multidisciplinary approach combining high-tech laboratory methods and close cooperation between treating physicians and pathologists.

4.
Brain Behav Evol ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38412843

RESUMO

INTRODUCTION: The changes in knee axial rotation plays an important role in traumatic and non-traumatic knee disorders. It is known that support afferentation can affect the axial rotator muscles. The condition of innervation of the ST and BFp has changed in non terrestrial and terrestrial vertebrates in evolution, thus we hypothesized this situation might be replayed by hindlimb unloading (HU). METHODS: In the present study the EMG activity of two hamstring muscles, m. semitendinosus (ST) and m. biceps femoris posterior (BFp), which are antagonists in axial rotation of the tibia, was examined before and after 7 days of HU. RESULTS: During locomotion and swimming the ST flexor-burst activity was increased in the stance to swing transition and in the retraction-protraction transition, respectively, while those of BFp remained unchanged. Both ST and BFp non-burst extensor activity increased during stepping and decreased during swimming. CONCLUSIONS: Our results show that: 1) The flexor-burst activity of ST and BFp depends differently on the load-dependent sensory input in the step cycle. 2) Shift of the activity gradient towards ST in the stance to swing transition could produce excessive internal tibia torque, which can be used as an experimental model of non-traumatic musculoskeletal disorders. 3) The mechanisms of activity of ST and BFp may be based on reciprocal activity of homologous muscles in primary tetrapodomorph and depend on the increased role of supraspinal control.

5.
J Phys Chem B ; 128(6): 1506-1514, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38315661

RESUMO

We address the challenge of representativity and dynamical consistency when unbonded fine-grained particles are collected together into coarse-grained particles. We implement a hybrid procedure for identifying and tracking the underlying fine-grained particles─e.g., atoms or molecules─by exchanging them between the coarse-grained particles periodically at a characteristic time. The exchange involves a back-mapping of the coarse-grained particles into fine-grained particles and a subsequent reassignment to coarse-grained particles conserving total mass and momentum. We find that an appropriate choice of the characteristic exchange time can lead to the correct effective diffusion rate of the fine-grained particles when simulated in hybrid coarse-grained dynamics. In the compressed (supercritical) fluid regime, without the exchange term, fine-grained particles remain associated with a given coarse-grained particle, leading to substantially lower diffusion rates than seen in all-atom molecular dynamics of the fine-grained particles. Thus, this work confirms the need for addressing the representativity of fine-grained particles within coarse-grained particles and offers a simple exchange mechanism so as to retain dynamical consistency between the fine- and coarse-grained scales.

6.
Cell ; 187(3): 692-711.e26, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38262408

RESUMO

Transcription factors (TFs) can define distinct cellular identities despite nearly identical DNA-binding specificities. One mechanism for achieving regulatory specificity is DNA-guided TF cooperativity. Although in vitro studies suggest that it may be common, examples of such cooperativity remain scarce in cellular contexts. Here, we demonstrate how "Coordinator," a long DNA motif composed of common motifs bound by many basic helix-loop-helix (bHLH) and homeodomain (HD) TFs, uniquely defines the regulatory regions of embryonic face and limb mesenchyme. Coordinator guides cooperative and selective binding between the bHLH family mesenchymal regulator TWIST1 and a collective of HD factors associated with regional identities in the face and limb. TWIST1 is required for HD binding and open chromatin at Coordinator sites, whereas HD factors stabilize TWIST1 occupancy at Coordinator and titrate it away from HD-independent sites. This cooperativity results in the shared regulation of genes involved in cell-type and positional identities and ultimately shapes facial morphology and evolution.


Assuntos
Proteínas de Ligação a DNA , Desenvolvimento Embrionário , Fatores de Transcrição , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sítios de Ligação , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Mesoderma/metabolismo , Fatores de Transcrição/metabolismo , Humanos , Animais , Camundongos , Extremidades/crescimento & desenvolvimento
7.
Nanomaterials (Basel) ; 14(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38251106

RESUMO

It is known that the dielectric layer (resonator) located behind the conducting plate of the bolometer system can significantly increase its sensitivity near the resonance frequencies. In this paper, the possibility of receiving broadband electromagnetic signals in a multilayer bolometric meta-material made of alternating conducting (e.g., silicon semiconductor) and dielectric layers is demonstrated both experimentally and numerically. It is shown that such a multilayer structure acts as a lattice of resonators and can significantly increase the width of the frequency band of efficient electromagnetic energy absorption. The parameters of the dielectric and semiconductor layers determine the frequency bands. Numerical modeling of the effect has been carried out under the conditions of our experiment. The numerical results show acceptable qualitative agreement with the experimental data. This study develops the previously proposed technique of resonant absorption of electromagnetic signals in bolometric structures.

8.
Magn Reson Chem ; 62(1): 61-68, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37937481

RESUMO

The reaction of butyryl chloride with ethynylbenzene in the presence of AlCl3 afforded a mixture of the Z/E-isomers of 1-chloro-2-phenylhex-1-en-3-one. 1,2-Diphenylethyne under these conditions gave a novel polycarbocycle core, 6aH-benzo[a]fluorene. The chemical structure of 11-chloro-5,6-diphenyl-6a-propyl-6aH-benzo[a]fluorene was established by means of IE-MS, 1 H, 13 C NMR, COSY, HSQC, HMBC, and 2D INADEQUATE technique.

9.
Cancers (Basel) ; 15(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38067249

RESUMO

This report presents the results of the assessment of MRD response by multicolor flow cytometry (MFC) with regard to the randomized use of pegylated asparaginase (PEG). In this study, PEG was randomly administered at a dose of 1000 U/m2 on day 3 of induction therapy in children with B-lineage ALL. METHODS: Conventional induction therapy consisted of dexamethasone, vincristine, and daunorubicin. MRD data was available in 502 patients who were randomized at the start of induction therapy, standard-risk (SR) patients into three (conventional induction without PEG, induction with additional PEG and with PEG but without daunorubicin) and intermediate-risk (ImR) patients into two groups (with additional PEG and without PEG). RESULTS: The single administration of PEG resulted in a significantly higher proportion of rapid responders, in SR patients even when no anthracyclines were used for induction. In the SR group, the event-free survival of the MFC-MRD fast responders was similar in the PEG- and PEG+ arms (92.0 ± 3.1% vs. 96.2 ± 1.5%, respectively), and the same unfavorable trend was observed for MFC-MRD slow responders (57.5 ± 12.3% vs. 66.7 ± 15.7%, respectively). Results were similar in ImR patients: (94.3 ± 3.2% vs. 95.1 ± 2.4%, for fast responders and 63.3 ± 7.6% vs. 78.1 ± 7.9%, for slow responders in PEG- and PEG+ arms, respectively). However, there is a large difference between the proportion of MFC-MRD slow responders in the PEG- and PEG+ groups (18.3% vs. 5.2% for the SR group and 44.2% vs. 25.0% for the ImR group). CONCLUSIONS: Therefore, early use of PEG-ASP not only leads to an accelerated reduction of blasts, but also to an excellent outcome in a significantly larger proportion of patients in both risk groups.

10.
Nat Commun ; 14(1): 8380, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38104196

RESUMO

How aging affects cells of the human brain active milieu remains largely unknown. Here, we analyze astrocytes and neurons in the neocortical tissue of younger (22-50 years) and older (51-72 years) adults. Aging decreases the amount of reduced mitochondrial cytochromes in astrocytes but not neurons. The protein-to-lipid ratio decreases in astrocytes and increases in neurons. Aged astrocytes show morphological atrophy quantified by the decreased length of branches, decreased volume fraction of leaflets, and shrinkage of the anatomical domain. Atrophy correlates with the loss of gap junction coupling between astrocytes and increased input resistance. Aging is accompanied by the upregulation of glial fibrillary acidic protein (GFAP) and downregulation of membrane-cytoskeleton linker ezrin associated with leaflets. No significant changes in neuronal excitability or spontaneous inhibitory postsynaptic signaling is observed. Thus, brain aging is associated with the impaired morphological presence and mitochondrial malfunction of cortical astrocytes, but not neurons.


Assuntos
Astrócitos , Córtex Cerebral , Humanos , Idoso , Astrócitos/metabolismo , Córtex Cerebral/metabolismo , Neurônios/metabolismo , Envelhecimento/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Atrofia/metabolismo
11.
Micromachines (Basel) ; 14(11)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-38004906

RESUMO

Amorphous germanium films on nonrefractory glass substrates were annealed by ultrashort near-infrared (1030 nm, 1.4 ps) and mid-infrared (1500 nm, 70 fs) laser pulses. Crystallization of germanium irradiated at a laser energy density (fluence) range from 25 to 400 mJ/cm2 under single-shot and multishot conditions was investigated using Raman spectroscopy. The dependence of the fraction of the crystalline phase on the fluence was obtained for picosecond and femtosecond laser annealing. The regimes of almost complete crystallization of germanium films over the entire thickness were obtained (from the analysis of Raman spectra with excitation of 785 nm laser). The possibility of scanning laser processing is shown, which can be used to create films of micro- and nanocrystalline germanium on flexible substrates.

12.
Int J Mol Sci ; 24(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37833906

RESUMO

Simultaneous multilineage hematologic malignancies are uncommon and associated with poorer prognosis than single-lineage leukemia or lymphoma. Here, we describe a concomitant malignant neoplasm in a 4-year-old boy. The child presented with massive lymphoproliferative syndrome, nasal breathing difficulties, and snoring. Morphological, immunocytochemical, and flow cytometry diagnostics showed coexistence of acute myeloid leukemia (AML) and peripheral T-cell lymphoma (PTCL). Molecular examination revealed a rare t(9;9)(q34;q34)/SET::NUP214 translocation as well as common TCR clonal rearrangements in both the bone marrow and lymph nodes. The disease showed primary refractoriness to both lymphoid and myeloid high-dose chemotherapy as well as combined targeted therapy (trametinib + ruxolitinib). Hence, HSCT was performed, and the patient has since been in complete remission for over a year. This observation highlights the importance of molecular techniques for determining the united nature of complex SET::NUP214-positive malignant neoplasms arising from precursor cells with high lineage plasticity.


Assuntos
Leucemia Mieloide Aguda , Transtornos Linfoproliferativos , Pré-Escolar , Humanos , Masculino , Medula Óssea/patologia , Leucemia Mieloide Aguda/complicações , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Indução de Remissão , Translocação Genética , Transtornos Linfoproliferativos/complicações , Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/genética
13.
J Clin Med ; 12(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37835049

RESUMO

Background: The incidence of pregnant women with uterine fibroids is increasing. As they are reactive to hormonal stimuli, in some cases, uterine fibroids tend to grow during pregnancy and potentially generate symptoms with different levels of severity, causing maternal-fetal complications. In very select cases, when other treatment strategies fail to manage symptoms and there is a substantial risk of adverse pregnancy outcomes, a surgical approach during pregnancy may be considered. Methods: From 2016 to 2021, the data from 28 pregnant women with symptomatic uterine fibroids who underwent laparotomic myomectomy during pregnancy were prospectively collected, and operative and maternal-fetal outcomes were analyzed (ClinicalTrial ID: NCT06009562). Results: The procedure was carried out between 14 and 16 weeks of pregnancy. Four (14.3%) patients had intraoperative complications (miscarriages) and nine (32.1%) had postoperative complications (threatened preterm birth). Overall, 24 (85.7%) women delivered at full term (mean: 38.2 gestational weeks), more than half (n = 13; 54.2%) by vaginal delivery, with normal fetal weights and 1 and 5 min Apgar scores. Conclusions: Laparotomic myomectomy during pregnancy can be considered in selected cases for uterine fibroids with severe symptoms when other treatment options have failed and there is high risk of adverse maternal-fetal outcomes.

14.
Int J Mol Sci ; 24(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685955

RESUMO

Acid-sensing ion channels (ASICs) are proton-gated ion channels that mediate nociception in the peripheral nervous system and contribute to fear and learning in the central nervous system. Sevanol was reported previously as a naturally-occurring ASIC inhibitor from thyme with favorable analgesic and anti-inflammatory activity. Using electrophysiological methods, we found that in the high micromolar range, the compound effectively inhibited homomeric ASIC1a and, in sub- and low-micromolar ranges, positively modulated the currents of α1ß2γ2 GABAA receptors. Next, we tested the compound in anxiety-related behavior models using a targeted delivery into the hippocampus with parallel electroencephalographic measurements. In the open field, 6 µM sevanol reduced both locomotor and θ-rhythmic activity similar to GABA, suggesting a primary action on the GABAergic system. At 300 µM, sevanol markedly suppressed passive avoidance behavior, implying alterations in conditioned fear memory. The observed effects could be linked to distinct mechanisms involving GABAAR and ASIC1a. These results elaborate the preclinical profile of sevanol as a candidate for drug development and support the role of ASIC channels in fear-related functions of the hippocampus.


Assuntos
Thymus (Planta) , Canais Iônicos Sensíveis a Ácido , Medo/efeitos dos fármacos , Ácido gama-Aminobutírico , Hipocampo/efeitos dos fármacos , Receptores de GABA-A/efeitos dos fármacos , Thymus (Planta)/química
18.
bioRxiv ; 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37398193

RESUMO

Transcription factors (TFs) can define distinct cellular identities despite nearly identical DNA-binding specificities. One mechanism for achieving regulatory specificity is DNA-guided TF cooperativity. Although in vitro studies suggest it may be common, examples of such cooperativity remain scarce in cellular contexts. Here, we demonstrate how 'Coordinator', a long DNA motif comprised of common motifs bound by many basic helix-loop-helix (bHLH) and homeodomain (HD) TFs, uniquely defines regulatory regions of embryonic face and limb mesenchyme. Coordinator guides cooperative and selective binding between the bHLH family mesenchymal regulator TWIST1 and a collective of HD factors associated with regional identities in the face and limb. TWIST1 is required for HD binding and open chromatin at Coordinator sites, while HD factors stabilize TWIST1 occupancy at Coordinator and titrate it away from HD-independent sites. This cooperativity results in shared regulation of genes involved in cell-type and positional identities, and ultimately shapes facial morphology and evolution.

19.
World J Clin Cases ; 11(10): 2226-2236, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37122523

RESUMO

BACKGROUND: An important area of effective control of the coronavirus disease 19 (COVID-19) pandemic is the study of the pathogenic features of severe acute respiratory syndrome coronavirus 2 infection, including those based on assessing the state of the intestinal microbiota and permeability. AIM: To study the clinical features of the new COVID-19 in patients with mild and moderate severity at the stage of hospitalization, to determine the role of hepatobiliary injury, intestinal permeability disorders, and changes in the qualitative and quantitative composition of the microbiota in the development of systemic inflammation in patients with COVID-19. METHODS: The study was performed in 80 patients with COVID-19, with an average age of 45 years, 19 of whom had mild disease, and 61 had moderate disease severity. The scope of the examination included traditional clinical, laboratory, biochemical, instrumental, and radiation studies, as well as original methods for studying microbiota and intestinal permeability. RESULTS: The clinical course of COVID-19 was studied, and the clinical and biochemical features, manifestations of systemic inflammation, and intestinal microbiome changes in patients with mild and moderate severity were identified. Intestinal permeability characteristics against the background of COVID-19 were evaluated by measuring levels of proinflammatory cytokines, insulin, faecal calprotectin, and zonulin. CONCLUSION: This study highlights the role of intestinal permeability and microbiota as the main drivers of gastroenterological manifestations and increased COVID-19 severity.

20.
Blood Adv ; 7(18): 5246-5257, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37216396

RESUMO

Langerhans cell histiocytosis (LCH) is a disorder with a variety of clinical signs. The most severe forms affect risk organs (RO). The established role of the BRAF V600E mutation in LCH led to a targeted approach. However, targeted therapy cannot cure the disease, and cessation leads to quick relapses. Here, we combined cytosine-arabinoside (Ara-C) and 2'-chlorodeoxyadenosine (2-CdA) with targeted therapy to achieve stable remission. Nineteen children were enrolled in the study: 13 were RO-positive (RO+) and 6 RO-negative (RO-). Five patients received the therapy upfront, whereas the other 14 received it as a second or third line. The protocol starts with 28 days of vemurafenib (20 mg/kg), which is followed by 3 courses of Ara-C and 2-CdA (100 mg/m2 every 12 h, 6 mg/m2 per day, days 1-5) with concomitant vemurafenib therapy. After that, vemurafenib therapy was stopped, and 3 courses of mono 2-CdA followed. All patients rapidly responded to vemurafenib: the median disease activity score decreased from 13 to 2 points in the RO+ group and from 4.5 to 0 points in the RO- group on day 28. All patients except 1 received complete protocol treatment, and 15 of them did not have disease progression. The 2-year reactivation/progression-free survival (RFS) for RO+ was 76.9% with a median follow-up of 21 months and 83.3% with a median follow-up of 29 months for RO-. Overall survival is 100%. Importantly, 1 patient experienced secondary myelodysplastic syndrome after 14 months from vemurafenib cessation. Our study demonstrates that combined vemurafenib plus 2-CdA and Ara-C is effective in a cohort of children with LCH, and the toxicity is manageable. This trial is registered at www.clinicaltrials.gov as NCT03585686.


Assuntos
Cladribina , Histiocitose de Células de Langerhans , Criança , Humanos , Cladribina/uso terapêutico , Vemurafenib/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Citarabina/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Histiocitose de Células de Langerhans/tratamento farmacológico , Histiocitose de Células de Langerhans/genética
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