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1.
Artigo em Inglês | MEDLINE | ID: mdl-39233015

RESUMO

BACKGROUND: Dedicator of cytokinesis 8 (DOCK8) deficiency is a primary immunodeficiency in which allogeneic hematopoietic cell transplantation (HCT) represents the only known cure. We tested the ability of a busulfan-based regimen to achieve reliable engraftment and high levels of donor chimerism with acceptable toxicity in a prospective clinical trial in DOCK8 deficiency. OBJECTIVE: To both evaluate the ability of HCT to reverse the clinical phenotype and to correct the immunologic abnormalities by 1-year post-HCT. METHODS: We conducted a prospective HCT trial for recipients with DOCK8 deficiency. Subjects were recruited from October 5th, 2010, to December 30th, 2022. Donor sources included fully matched related (MRD) and unrelated (MUD) and haploidentical (Haplo) donors. The reduced toxicity, myeloablative conditioning regimen contained no serotherapy. Graft-versus-host disease (GVHD) prophylaxis included either a calcineurin inhibitor (CNI) with methotrexate (MTX) or post-HCT cyclophosphamide (PT/Cy) followed by tacrolimus and mycophenolate mofetil (MMF). The trial was later amended to study PT/Cy in all patients. (ClinicalTrials.gov NCT01176006). RESULTS: Thirty-six subjects, children, and adults (median age 16.4 years) underwent HCT for DOCK8 deficiency. Most patients, 33 of 36 (92%), achieved full (≥98%) donor chimerism in whole blood as early as day +30. With a median potential follow-up of 7.4 years, 29 (80.6%) were alive with no evidence of new DOCK8 deficiency-related complications. PT/Cy was effective in reducing the risk of acute GVHD in patients who had received MUDs and Haplo transplants, but it was associated with transient delays in immune-reconstitution and hemorrhagic cystitis (HC). CONCLUSION: A busulfan-based HCT regimen using PT/Cy for GVHD prophylaxis and a broad range of donor types and hematopoietic cell sources were well-tolerated, leading to the reversal of the clinical immunophenotype.

3.
Sci Bull (Beijing) ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39174404

RESUMO

After several decades of studies of high-temperature superconductivity, there is no compelling theory for the mechanism yet; however, the spin fluctuations have been widely believed to play a crucial role in forming the superconducting Cooper pairs. The recent discovery of high-temperature superconductivity near 80 K in the bilayer nickelate La3Ni2O7 under pressure provides a new platform to elucidate the origins of high-temperature superconductivity. We perform elastic and inelastic neutron scattering studies on a polycrystalline sample of La3Ni2O7-δ at ambient pressure. No magnetic order can be identified down to 10 K. The absence of long-range magnetic order in neutron diffraction measurements may be ascribed to the smallness of the magnetic moment. However, we observe a weak flat spin-fluctuation signal in the inelastic scattering spectra at ∼ 45 meV. The observed spin excitations could be interpreted as a result of strong interlayer and weak intralayer magnetic couplings for stripe-type antiferromagnetic orders. Our results provide crucial information on the spin dynamics and are thus important for understanding the superconductivity in La3Ni2O7.

4.
Sci Rep ; 14(1): 19345, 2024 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164366

RESUMO

There are currently no available FDA-cleared biodosimetry tools for rapid and accurate assessment of absorbed radiation dose following a radiation/nuclear incident. Previously we developed a protein biomarker-based FAST-DOSE bioassay system for biodosimetry. The aim of this study was to integrate an ELISA platform with two high-performing FAST-DOSE biomarkers, BAX and DDB2, and to construct machine learning models that employ a multiparametric biomarker strategy for enhancing the accuracy of exposure classification and radiation dose prediction. The bioassay showed 97.92% and 96% accuracy in classifying samples in human and non-human primate (NHP) blood samples exposed ex vivo to 0-5 Gy X-rays, respectively up to 48 h after exposure, and an adequate correlation between reconstructed and actual dose in the human samples (R2 = 0.79, RMSE = 0.80 Gy, and MAE = 0.63 Gy) and NHP (R2 = 0.80, RMSE = 0.78 Gy, and MAE = 0.61 Gy). Biomarker measurements in vivo from four NHPs exposed to a single 2.5 Gy total body dose showed a persistent upregulation in blood samples collected on days 2 and 5 after irradiation. The data indicates that using a combined approach of targeted proteins can increase bioassay sensitivity and provide a more accurate dose prediction.


Assuntos
Biomarcadores , Proteínas de Ligação a DNA , Proteína X Associada a bcl-2 , Animais , Humanos , Biomarcadores/sangue , Proteínas de Ligação a DNA/sangue , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/sangue , Exposição à Radiação/efeitos adversos , Masculino , Radiometria/métodos , Macaca mulatta , Feminino , Aprendizado de Máquina , Doses de Radiação
5.
ACS Nano ; 18(35): 24591-24602, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39161977

RESUMO

Using cyclic voltammetry under illumination, we recently demonstrated that CdS quantum dots (QDs) form charge donor states that live for at least several minutes after illumination ends, ∼12 orders of magnitude longer than expected for free carriers. This time scale suggests that the conventionally accepted mechanism of charge transfer, wherein charges directly transfer to an acceptor following exciton dissociation, cannot be complete. Because of these long time scales, this unconventional pathway is not readily observed using time-resolved spectroscopy to probe charge transfer dynamics. Here, we investigated the chemical nature of these charge donor states using cyclic voltammetry under illumination coupled with NMR spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and optical spectroscopy. Our data reveal that charges are stored locally rather than as free carriers, and the number of charges stored is dependent on the QD surface ligation and stoichiometry. Altogether, our results confirm that electrons are stored at ligated surface Cd, these sites are competent charge donors, and this storage is charge balanced by X-type ligand desorption. We found that charge storage occurs in every QD system studied, including CdS, CdSe, and InP capped with carboxylate and phosphonate ligands.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39166750

RESUMO

OBJECTIVES: Animal models indicate that hepatic insulin resistance (IR) promotes cholesterol gallstone disease (GSD). We sought to determine whether hepatic and whole-body IR are associated with incident GSD. METHODS: At baseline, 450 Southwestern Indigenous American adults without GSD were included. Participants had a 2-step hyperinsulinemic-euglycemic clamp with glucose tracer at submaximal and maximal insulin stimulation (240 and 2400 pmol/m2/min) for whole-body IR (M-low and M-high) and hepatic glucose production (HGP) before and during submaximal insulin infusion (HGP-basal and HGP-insulin). Incident GSD was identified during follow-up visits conducted at ∼2-year intervals. The associations of HGP (basal, insulin, and % suppression), M-low, and M-high with risk of GSD were assessed by Cox regression models adjusted for age, sex, body fat (%), glucose, and insulin. RESULTS: Sixty participants (13%) developed GSD (median follow-up: 11.6 years). Participants who developed GSD were of similar age and whole-body IR as those who did not (p's> 0.07), but were more likely to be female, have higher body fat, higher HGP-basal, and HGP-insulin, and lower % suppression of HGP (p's<0.02). In separate adjusted models, higher HGP-insulin and lower % suppression of HGP were associated with increased risk for GSD (hazard ratio [HR] per SD: HR 1.38, 95% CI 1.12, 1.69, p=0.002; HR 1.41 95% CI 1.16-1.72, p=0.0007). HGP-basal, M-low, and M-high were not associated with GSD in adjusted models (p's>0.22). CONCLUSIONS: Resistance to insulin suppression of HGP increases risk for GSD. Hepatic IR is a link between GSD and other conditions of the metabolic syndrome.

7.
Sens Diagn ; 3(8): 1344-1352, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39129862

RESUMO

In large-scale radiation exposure events, the ability to triage potential victims by the received radiation dosage is crucial. This can be evaluated by radiation-induced biological changes. Radiation-responsive mRNA is a class of biomarkers that has been explored for dose-dependency with methods such as RT-qPCR. However, these methods are challenging to implement for point-of-care devices. We have designed and used molecular beacons as probes for the measurement of radiation-induced changes of intracellular mRNA in a microfluidic device towards determining radiation dosage. Our experiments, in which fixed TK6 cells labeled with a molecular beacon specific to BAX mRNA exhibited dose-dependent fluorescence in a manner consistent with RT-qPCR analysis, demonstrate that such intracellular molecular probes can potentially be used in point-of-care radiation biodosimetry. This proof of concept could readily be extended to any RNA-based test to provide direct measurements at the bedside.

8.
PLoS One ; 19(8): e0307268, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39093910

RESUMO

INTRODUCTION: Understanding genetic contributors to sarcopenia (age-related loss of muscle strength and mass) is key to finding effective therapies. Variants of the bradykinin receptor 2 (BDKRB2) have been linked to athletic and muscle performance. The rs1799722-9 and rs5810761 T alleles have been shown to be overrepresented in endurance athletes, possibly due to increased transcriptional rates of the receptor. These variants have been rarely studied in older people or people with sarcopenia. METHODS: We performed a post hoc sub-study of the Leucine and ACE (LACE) inhibitor trial, which enrolled 145 participants aged ≥70 years with low grip strength and low gait speed. Participants' blood samples were genotyped for rs179972 using TaqMan and rs5810761 by amplification through Hotstar Taq. Genotypes were compared with outcomes of physical performance and body composition measures. RESULTS: Data from 136 individuals were included in the analysis. For rs1799722 the genotype frequency (TT: 17, CC: 48, CT: 71) remained in Hardy-Weinberg Equilibrium (HWE p = 0.248). There was no difference between the genotypes for six-Minute Walk Distance (6MWD) or Short Physical Performance Battery (SPPB). Men with the TT genotype had a significantly greater 6MWD than other genotypes (TT 400m vs CT 310m vs CC 314m, p = 0.027), and greater leg muscle mass (TT 17.59kg vs CT 15.04kg vs CC 15.65kg, p = 0.007). For rs5810761, the genotype frequency (-9-9: 31, +9+9: 43, -9+9: 60) remained in HWE (p = 0.269). The +9+9 genotype was associated with a significant change in SPPB score at 12 months (-9-9 0 vs -9+9 0 vs +9+9-1, p<0.001), suggesting an improvement. In men, the -9-9 genotype was associated with lower arm fat (-9-9 2.39kg vs -9+9 2.72kg vs +9+9 2.76kg, p = 0.019). CONCLUSION: In men, the rs1799722 TT genotype was associated with longer 6MWD and greater leg muscle mass, while the rs5810761 -9-9 genotype was associated with lower arm fat mass.


Assuntos
Desempenho Físico Funcional , Receptor B2 da Bradicinina , Sarcopenia , Humanos , Masculino , Idoso , Feminino , Receptor B2 da Bradicinina/genética , Sarcopenia/genética , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Genótipo , Alelos , Polimorfismo de Nucleotídeo Único , Composição Corporal , Leucina/genética , Idoso de 80 Anos ou mais , Força da Mão , Força Muscular/genética
9.
Anxiety Stress Coping ; : 1-17, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39021066

RESUMO

BACKGROUND: College students with ADHD have difficulties with emotion regulation and have poorer academic skills than peers without ADHD; however, less is known regarding the relation between ADHD symptoms, maladaptive cognitive emotion regulation strategies (CERS), and learning effectiveness. OBJECTIVES: We examined whether maladaptive CERS predicted learning effectiveness, and whether this relation was moderated by ADHD symptoms. DESIGN: A cross-sectional online survey. METHODS: College students (N = 4,183; Mage = 19.24; 70.1% female) at eight universities completed a battery as part of a larger study. RESULTS: College students in our elevated ADHD group used significantly more maladaptive CERS and performed worse in three domains of learning effectiveness (i.e., Academic Self-Efficacy [ASE], Organization and Attention to Study [OAS], Stress and Time Press [STP]) than college students in our non-ADHD group. Further, ADHD symptoms moderated the relation between maladaptive CERS and OAS, such that individuals with the highest levels of ADHD symptoms were less impacted by maladaptive CERS. CONCLUSION: Increased use of maladaptive CERS is unique to ADHD rather than lack of adaptive CERS. Also, maladaptive CERS and low ADHD symptoms interact to predict poor OAS. Interventions for college students, regardless of ADHD status, should incorporate emotion regulation components to improve learning effectiveness.

10.
Mater Adv ; 5(13): 5561-5571, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38957404

RESUMO

Respiratory diseases, including influenza, infectious pneumonia, and severe acute respiratory syndrome (SARS), are a leading cause of morbidity and mortality worldwide. The recent COVID-19 pandemic claimed over 6.9 million lives globally. With the possibility of future pandemics, the creation of affordable antimicrobial meshes for protective gear, such as facemasks, is essential. Electrospinning has been a focus for much of this research, but most approaches are complex and expensive, often wasting raw materials by distributing antiviral agents throughout the mesh despite the fact they can only be active if at the fibre surface. Here, we report a low cost and efficient one-step method to produce nanofibre meshes with antimicrobial activity, including against SARS-CoV-2. Cetrimonium bromide (CTAB) was deposited directly onto the surface of polycaprolactone (PCL) fibres by coaxial electrospinning. The CTAB-coated samples have denser meshes with finer nanofibres than non-coated PCL fibres (mean diameter: ∼300 nm versus ∼900 nm, with mean pore size: ∼300 nm versus > 600 nm). The formulations have > 90% coating efficiency and exhibit a burst release of CTAB upon coming into contact with aqueous media. The CTAB-coated materials have strong antibacterial activity against Staphylococcus aureus (ca. 100%) and Pseudomonas aeruginosa (96.5 ± 4.1%) bacteria, as well as potent antiviral activity with over 99.9% efficacy against both respiratory syncytial virus and SARS-CoV-2. The CTAB-coated nanofibre mesh thus has great potential to form a mask material for preventing both bacterial and viral respiratory infections.

11.
Nat Commun ; 15(1): 6248, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39048583

RESUMO

Stacking two-dimensional (2D) van der Waals (vdW) materials in a layered bulk structure provides an appealing platform for the emergence of exotic physical properties. As a vdW crystal with exceptional plasticity, InSe offers the opportunity to explore various effects arising from the coupling of its peculiar mechanical behaviors and other physical properties. Here, we employ neutron scattering techniques to investigate the correlations of plastic interlayer slip, lattice anharmonicity, and thermal transport in InSe crystals. Not only are the interlayer slip direction and magnitude well captured by shifts in the Bragg reflections, but we also observe a deviation from the expected Debye behaviour in the heat capacity and lattice thermal conductivity. Combining the experimental data with first-principles calculations, we tentatively attribute the observed evidence of strong phonon-phonon interactions to a combination of a large acoustic-optical frequency resonance and a nesting effect. These findings correlate the macroscopic plastic slip and the microscopic lattice dynamics, providing insights into the mechano-thermo coupling and modulation in 2D vdW materials.

12.
Chembiochem ; : e202400278, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953596

RESUMO

Bio-processes based on enzymatic catalysis play a major role in the development of green, sustainable processes, and the discovery of new enzymes is key to this approach. In this work, we analysed ten metagenomes and retrieved 48 genes coding for deoxyribose-5-phosphate aldolases (DERAs, EC 4.1.2.4) using a sequence-based approach. These sequences were recombinantly expressed in Escherichia coli and screened for activity towards a range of aldol additions. Among these, one enzyme, DERA-61, proved to be particularly interesting and catalysed the aldol addition of furfural or benzaldehyde with acetone, butanone and cyclobutanone with unprecedented activity. The product of these reactions, aldols, can find applications as building blocks in the synthesis of biologically active compounds. Screening was carried out to identify optimized reaction conditions targeting temperature, pH, and salt concentrations. Lastly, the kinetics and the stereochemistry of the products were investigated, revealing that DERA-61 and other metagenomic DERAs have superior activity and stereoselectivity when they are provided with non-natural substrates, compared to well-known DERAs.

13.
JAMA Netw Open ; 7(7): e2421877, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39073816

RESUMO

Importance: Child physical and emotional abuse and neglect may affect epigenetic signatures of accelerated aging several years after the exposure. Objective: To examine the longitudinal outcomes of early-childhood and midchildhood exposures to maltreatment on later childhood and adolescent profiles of epigenetic accelerated aging. Design, Setting, and Participants: This cohort study used data from the Future of Families and Child Wellbeing Study (enrolled 1998-2000), a US birth cohort study with available DNA methylation (DNAm) data at ages 9 and 15 years (assayed between 2017 and 2020) and phenotypic data at birth (wave 1), and ages 3 (wave 3), 5 (wave 4), 9 (wave 5), and 15 (wave 6) years. Data were analyzed between June 18 and December 10, 2023. Exposures: Emotional aggression, physical assault, emotional neglect, and physical neglect via the Parent-Child Conflict Tactics Scale at ages 3 and 5 years. Main Outcomes and Measures: Epigenetic accelerated aging (DNAmAA) was measured using 3 machine learning-derived surrogates of aging (GrimAge, PhenoAge, and DunedinPACE) and 2 machine learning-derived surrogates of age (Horvath and PedBE), residualized for age in months. Results: A total of 1971 children (992 [50.3%] male) representative of births in large US cities between 1998 and 2000 were included. Physical assault at age 3 years was positively associated with DNAmAA for PhenoAge (ß = 0.073; 95% CI, 0.019-0.127), and emotional aggression at age 3 years was negatively associated with PhenoAge DNAmAA (ß = -0.107; 95% CI, -0.162 to -0.052). Emotional neglect at age 5 years was positively associated with PhenoAge DNAmAA (ß = 0.051; 95% CI, 0.006-0.097). Cumulative exposure to physical assault between ages 3 and 5 years was positively associated with PhenoAge DNAmAA (ß = 0.063; 95% CI, 0.003-0.123); emotional aggression was negatively associated with PhenoAge DNAmAA (ß = -0.104; 95% CI, -0.165 to -0.043). The association of these measures with age 15 years PhenoAge DNAmAA was almost fully mediated by age 9 years PhenoAge DNAm age acceleration. Similar patterns were found for GrimAge, DunedinPACE, and PhenoAge, but only those for PhenoAge remained after adjustments for multiple comparisons. Conclusions and Relevance: In this cohort study, altered patterns of DNAmAA were sensitive to the type and timing of child maltreatment exposure and appeared to be associated with more proximate biological embedding of stress.


Assuntos
Maus-Tratos Infantis , Epigênese Genética , Epigenômica , Humanos , Criança , Maus-Tratos Infantis/psicologia , Maus-Tratos Infantis/estatística & dados numéricos , Masculino , Feminino , Adolescente , Estudos Longitudinais , Epigenômica/métodos , Pré-Escolar , Metilação de DNA , Envelhecimento/genética , Envelhecimento/psicologia , Estados Unidos , Estudos de Coortes
14.
Pathogens ; 13(7)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39057767

RESUMO

INTRODUCTION: Increasing drug resistance and the absence of a cure necessitates exploration of novel treatment strategies for people living with HIV (PLWH). Targeting of soluble co-inhibitory immune checkpoint molecules (sICMs) represents a novel, potentially effective strategy in the management of HIV. METHODS: In this retrospective, longitudinal, observational study, the plasma levels of five prominent co-inhibitory sICMs-CTLA-4, LAG-3, PD-1 and its ligand PD-L1, as well as TIM-3-were quantified in 68 PLWH-before and one year after antiretroviral therapy (ART)-and compared with those of 15 healthy control participants. RESULTS: Relative to control participants, PLWH had substantially elevated pre-treatment levels of all five co-inhibitory sICMs (p < 0.0001-p < 0.0657), which, over the 12-month period of ART, remained significantly higher than those of controls (p < 0.0367-p < 0.0001). PLWH with advanced disease, reflected by a CD4+ T cell count <200 cells/mm3 before ART, had the lowest levels of CTLA-4 and LAG-3, while participants with pre-treatment HIV viral loads ≥100,000 copies/mL had higher pre-treatment levels of TIM-3, which also persisted at 12 months. CONCLUSIONS: Plasma levels of CTLA-4, LAG-3, PD-1, PD-L1 and TIM-3 were significantly elevated in treatment-naïve PLWH and remained so following one year of virally-suppressive ART, possibly identifying LAG-3 and TIM-3 in particular as potential targets for adjuvant immunotherapy.

15.
Clin Immunol ; 266: 110323, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39029640

RESUMO

The African continent reported the least number of COVID-19 cases and deaths of all the continents, although the exact reasons for this are still unclear. In addition, little is known about the immunological profiles associated with COVID-19 mortality in Africa. The present study compared clinical and immunological parameters, as well as treatment outcomes in patients admitted with COVID-19 in Pretoria, South Africa, to determine if these parameters correlated with mortality in this population. The in-hospital mortality rate for the cohort was 15.79%. The mortality rate in people living with HIV (PLWH) was 10.81% and 17.16% in people without HIV (p = 0.395). No differences in age (p = 0.099), gender (p = 0.127) or comorbidities were found between deceased patients and those who survived. All four of the PLWH who died had a CD4+ T-cell count <200 cells/mm3, a significantly higher HIV viral load than those who survived (p = 0.009), and none were receiving antiretroviral therapy. Seven of 174 (4%) patients had evidence of auto-antibodies neutralizing Type 1 interferons (IFNs). Two of the them died, and their presence was significantly associated with mortality (p = 0.042). In the adjusted model, the only clinical parameters associated with mortality were: higher fraction of inspired oxygen (FiO2) (OR: 3.308, p = 0.011) indicating a greater need for oxygen, high creatinine (OR: 4.424, p = 0.001) and lower platelet counts (OR: 0.203, p = 0.009), possibly secondary to immunothrombosis. Overall, expression of the co-receptor CD86 (p = 0.021) on monocytes and percentages of CD8+ effector memory 2 T-cells (OR: 0.45, p = 0.027) was lower in deceased patients. Decreased CD86 expression impairs the development and survival of effector memory T-cells. Deceased patients had higher concentrations of RANTES (p = 0.003), eotaxin (p = 0.003) and interleukin (IL)-8 (p < 0.001), all involved in the activation and recruitment of innate immune cells. They also had lower concentrations of transforming growth factor (TGF)-ß1 (p = 0.40), indicating an impaired anti-inflammatory response. The immunological profile associated with COVID-19 mortality in South Africa points to the role of aberrate innate immune responses.


Assuntos
COVID-19 , Infecções por HIV , Imunidade Inata , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/mortalidade , África do Sul/epidemiologia , Masculino , Feminino , Imunidade Inata/imunologia , Infecções por HIV/imunologia , Infecções por HIV/mortalidade , Infecções por HIV/tratamento farmacológico , Pessoa de Meia-Idade , Adulto , SARS-CoV-2/imunologia , Contagem de Linfócito CD4 , Mortalidade Hospitalar , Carga Viral , Idoso
16.
Cell Rep ; 43(8): 114542, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39046877

RESUMO

Granulocyte colony-stimulating factor (G-CSF) is widely used to enhance myeloid recovery after chemotherapy and to mobilize hematopoietic stem cells (HSCs) for transplantation. Unfortunately, through the course of chemotherapy, cancer patients can acquire leukemogenic mutations that cause therapy-related myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML). This raises the question of whether therapeutic G-CSF might potentiate therapy-related MDS/AML by disproportionately stimulating mutant HSCs and other myeloid progenitors. A common mutation in therapy-related MDS/AML involves chromosome 7 deletions that inactivate many tumor suppressor genes, including KMT2C. Here, we show that Kmt2c deletions hypersensitize murine HSCs and myeloid progenitors to G-CSF, as evidenced by increased HSC mobilization and enhanced granulocyte production from granulocyte-monocyte progenitors (GMPs). Furthermore, Kmt2c attenuates the G-CSF response independently from its SET methyltransferase function. Altogether, the data raise concerns that monosomy 7 can hypersensitize progenitors to G-CSF, such that clinical use of G-CSF may amplify the risk of therapy-related MDS/AML.


Assuntos
Fator Estimulador de Colônias de Granulócitos , Granulócitos , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas , Fator Estimulador de Colônias de Granulócitos/metabolismo , Animais , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Camundongos , Granulócitos/metabolismo , Granulócitos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Humanos , Metiltransferases/metabolismo , Metiltransferases/genética
17.
Radiat Res ; 202(3): 541-551, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39034036

RESUMO

After a large-scale radiological or nuclear event, hundreds of thousands of people may be exposed to ionizing radiation and require subsequent medical management. Acute exposure to moderate doses (2-6 Gy) of radiation can lead to the hematopoietic acute radiation syndrome, in which the bone marrow (BM) is severely compromised, and severe hemorrhage and infection are common. Previously, we have developed a panel of intracellular protein markers (FDXR, ACTN1, DDB2, BAX, p53 and TSPYL2), designed to reconstruct absorbed radiation dose from human peripheral blood (PB) leukocyte samples in humanized mice up to 3 days after exposure. The objective of this work was to continue to use the humanized mouse model to evaluate biomarker dose-/time- kinetics in human PB leukocytes in vivo, at an earlier (day 2) and later (day 7) time point, after exposure to total-body irradiation (TBI) doses of 0 to 2 Gy of X rays. In addition, to assess hematological sensitivity and radiation-induced injury, PB leukocyte cell counts, human BM hematopoietic stem cell (HSC) and progenitor cell [multipotent progenitor (MPP), common myeloid progenitor (CMP), granulocyte myeloid progenitor (GMP), megakaryocyte/erythrocyte progenitor (MEP) and multi-lymphoid progenitor (MLP)] levels were measured, and their correlation was also examined as the BM damages are difficult to assess by routine tests. Peripheral blood B-cells were significantly lower after TBI doses of 0.5 Gy on day 2 and 2 Gy on days 2 and 7; T-cells were significantly reduced only on day 2 after 2 Gy TBI. Bone marrow HSCs and MPP cells showed a dose-dependent depletion after irradiation with 0.5 Gy and 2 Gy on day 2, and after 1 Gy and 2 Gy on day 7. Circulating B cells correlated with HSCs, MPP and MLP cells on day 2, whereas T cells correlated with MPP, and myeloid cells correlated with MLP cells. On day 7, B cells correlated with MPP, CMP, GMP and MEP, while myeloid cells correlated with CMP, GMP and MEP. The intracellular leukocyte biomarkers were able to discriminate unirradiated and irradiated samples at different time points calculated by receiver operating characteristic (ROC) curve. Using machine learning algorithm methods, combining ACTN1, p53, TSPYL2 and PB-T cell and PB-B cell counts served as a strong predictor (area under the ROC >0.8) to distinguish unirradiated and irradiated samples independent of the days after TBI. The results further validated our biomarker-based triage assay and additionally evaluated the radiation sensitivity of the hematopoietic system after TBI exposures.


Assuntos
Biomarcadores , Animais , Camundongos , Humanos , Biomarcadores/sangue , Radiometria/métodos , Irradiação Corporal Total/efeitos adversos , Células-Tronco Hematopoéticas/efeitos da radiação , Células-Tronco Hematopoéticas/citologia , Relação Dose-Resposta à Radiação , Modelos Animais de Doenças
18.
Artigo em Inglês | MEDLINE | ID: mdl-38940184

RESUMO

OBJECTIVE: To assess the uptake of a multidisciplinary team approach in obstetric disseminated intravascular coagulopathy (DIC) management in a low- to middle-income country. METHODS: A cross-sectional observational study, in which a semi-structured and pre-tested questionnaire was used to collect data on the uptake by Nigerian obstetricians of the multidisciplinary team approach to obstetric DIC management. RESULTS: A total of 171 obstetricians responded, 82 (48.0%) were consultants and 89 (52.0%) were specialist registrars. Most (165; 96.5%) practiced in tertiary healthcare facilities and the multidisciplinary team approach was the most preferred (162; 94.7%) management approach. In all, 142 (83.0%) supported the invitation of hematologists always in the management whereas 115 (67.3%) participants recommended that involvement of specialists in the treatment should be when clinical presentation was suggestive of DIC. No significant association existed between years of obstetric practice and adoption of a multidisciplinary team-based approach (χ2 = 9.590; P = 0.252). CONCLUSION: A multidisciplinary approach is widely adopted in the management of obstetric DIC, with hematologists being a key member of the team.

19.
PhytoKeys ; 240: 1-552, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38912426

RESUMO

Caesalpinioideae is the second largest subfamily of legumes (Leguminosae) with ca. 4680 species and 163 genera. It is an ecologically and economically important group formed of mostly woody perennials that range from large canopy emergent trees to functionally herbaceous geoxyles, lianas and shrubs, and which has a global distribution, occurring on every continent except Antarctica. Following the recent re-circumscription of 15 Caesalpinioideae genera as presented in Advances in Legume Systematics 14, Part 1, and using as a basis a phylogenomic analysis of 997 nuclear gene sequences for 420 species and all but five of the genera currently recognised in the subfamily, we present a new higher-level classification for the subfamily. The new classification of Caesalpinioideae comprises eleven tribes, all of which are either new, reinstated or re-circumscribed at this rank: Caesalpinieae Rchb. (27 genera / ca. 223 species), Campsiandreae LPWG (2 / 5-22), Cassieae Bronn (7 / 695), Ceratonieae Rchb. (4 / 6), Dimorphandreae Benth. (4 / 35), Erythrophleeae LPWG (2 /13), Gleditsieae Nakai (3 / 20), Mimoseae Bronn (100 / ca. 3510), Pterogyneae LPWG (1 / 1), Schizolobieae Nakai (8 / 42-43), Sclerolobieae Benth. & Hook. f. (5 / ca. 113). Although many of these lineages have been recognised and named in the past, either as tribes or informal generic groups, their circumscriptions have varied widely and changed over the past decades, such that all the tribes described here differ in generic membership from those previously recognised. Importantly, the approximately 3500 species and 100 genera of the former subfamily Mimosoideae are now placed in the reinstated, but newly circumscribed, tribe Mimoseae. Because of the large size and ecological importance of the tribe, we also provide a clade-based classification system for Mimoseae that includes 17 named lower-level clades. Fourteen of the 100 Mimoseae genera remain unplaced in these lower-level clades: eight are resolved in two grades and six are phylogenetically isolated monogeneric lineages. In addition to the new classification, we provide a key to genera, morphological descriptions and notes for all 163 genera, all tribes, and all named clades. The diversity of growth forms, foliage, flowers and fruits are illustrated for all genera, and for each genus we also provide a distribution map, based on quality-controlled herbarium specimen localities. A glossary for specialised terms used in legume morphology is provided. This new phylogenetically based classification of Caesalpinioideae provides a solid system for communication and a framework for downstream analyses of biogeography, trait evolution and diversification, as well as for taxonomic revision of still understudied genera.

20.
Angew Chem Int Ed Engl ; : e202410283, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943496

RESUMO

The direct synthesis of alkenes from alkynes usually requires the use of transition-metal catalysts. Unfortunately, efficient biocatalytic alternatives for this transformation have yet to be discovered. Herein, the selective bioreduction of electron-deficient alkynes to alkenes catalysed by ene-reductases (EREDs) is described. Alkynes bearing ketone, aldehyde, ester, and nitrile moieties have been effectively reduced with excellent conversions and stereoselectivities, observing clear trends for the E/Z ratios depending on the nature of the electron-withdrawing group. In the case of cyanoalkynes, (Z)-alkenes were obtained as the major product, and the reaction scope was expanded to a wide variety of aromatic substrates (up to >99 % conversion, and Z/E stereoselectivities of up to >99/1). Other alkynes containing aldehyde, ketone, or ester functionalities also proved to be excellent substrates, and interestingly gave the corresponding (E)-alkenes. Preparative biotransformations were performed on a 0.4 mmol scale, producing the desired (Z)-cyanoalkenes with good to excellent isolated yields (63-97 %). This novel reactivity has been rationalised through molecular docking by predicting the binding poses of key molecules in the ERED-pu-0006 active site.

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