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1.
Neural Regen Res ; 20(2): 394-401, 2025 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38819042

RESUMO

During the development of the nervous system, there is an overproduction of neurons and synapses. Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or strengthening. We have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway, at the neuromuscular junction, in the axonal development and synapse elimination process versus the synapse consolidation. The purpose of this review is to describe the neurotrophic influence on developmental synapse elimination, in relation to other molecular pathways that we and others have found to regulate this process. In particular, we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors, coupled to downstream serine-threonine protein kinases A and C (PKA and PKC) and voltage-gated calcium channels, at different nerve endings in developmental competition. The dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site, influence each other, and require careful studies to individualize the mechanisms of specific endings. We describe an activity-dependent balance (related to the extent of transmitter release) between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon terminals. The downstream displacement of the PKA/PKC activity ratio to lower values, both in competing nerve terminals and at postsynaptic sites, plays a relevant role in controlling the elimination of supernumerary synapses. Finally, calcium entry through L- and P/Q- subtypes of voltage-gated calcium channels (both channels are present, together with the N-type channel in developing nerve terminals) contributes to reduce transmitter release and promote withdrawal of the most unfavorable nerve terminals during elimination (the weakest in acetylcholine release and those that have already become silent). The main findings contribute to a better understanding of punishment-rewarding interactions between nerve endings during development. Identifying the molecular targets and signaling pathways that allow synapse consolidation or withdrawal of synapses in different situations is important for potential therapies in neurodegenerative diseases.

2.
Pharmaceutics ; 16(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38931919

RESUMO

Many physical and chemical properties of solids, such as strength, plasticity, dispersibility, solubility and dissolution are determined by defects in the crystal structure. The aim of this work is to study in situ dynamic, dispersion, chemical, biological and surface properties of lacosamide powder after a complete cycle of mechanical loading by laser scattering, electron microscopy, FR-IR and biopharmaceutical approaches. The SLS method demonstrated the spontaneous tendency toward surface-energy reduction due to aggregation during micronisation. DLS analysis showed conformational changes of colloidal particles as supramolecular complexes depending on the loading time on the solid. SEM analysis demonstrated the conglomeration of needle-like lacosamide particles after 60 min of milling time and the transition to a glassy state with isotropy of properties by the end of the tribochemistry cycle. The following dynamic properties of lacosamide were established: elastic and plastic deformation boundaries, region of inhomogeneous deformation and fracture point. The ratio of dissolution-rate constants in water of samples before and after a full cycle of loading was 2.4. The lacosamide sample, which underwent a full cycle of mechanical loading, showed improved kinetics of API release via analysis of dissolution profiles in 0.1 M HCl medium. The observed activation-energy values of the cell-death biosensor process in aqueous solutions of the lacosamide samples before and after the complete tribochemical cycle were 207 kJmol-1 and 145 kJmol-1, respectively. The equilibrium time of dissolution and activation of cell-biosensor death corresponding to 20 min of mechanical loading on a solid was determined. The current study may have important practical significance for the transformation and management of the properties of drug substances in solid form and in solutions and for increasing the strength of drug matrices by pre-strain hardening via structural rearrangements during mechanical loading.

3.
Pharmaceutics ; 16(6)2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38931934

RESUMO

In the treatment of experimental neurodegeneration with disaccharide trehalose, various regimens are used, predominantly a 2% solution, drunk for several weeks. We studied the effects of different regimens of dietary trehalose treatment in an amyloid-ß (Aß) 25-35-induced murine model of Alzheimer's disease (AD). Aß-treated mice received 2% trehalose solution daily, 4% trehalose solution daily (continuous mode) or every other day (intermittent mode), to drink for two weeks. We revealed the dose-dependent effects on autophagy activation in the frontal cortex and hippocampus, and the restoration of behavioral disturbances. A continuous intake of 4% trehalose solution caused the greatest activation of autophagy and the complete recovery of step-through latency in the passive avoidance test that corresponds to associative long-term memory and learning. This regimen also produced an anxiolytic effect in the open field. The effects of all the regimens studied were similar in Aß load, neuroinflammatory response, and neuronal density in the frontal cortex and hippocampus. Trehalose successfully restored these parameters to the levels of the control group. Thus, high doses of trehalose had increased efficacy towards cognitive impairment in a model of early AD-like pathology. These findings could be taken into account for translational studies and the development of clinical approaches for AD therapy using trehalose.

4.
Polymers (Basel) ; 16(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38932086

RESUMO

In this study, we report an easy approach for the production of aqueous dispersions of C60 fullerene with good stability. Maleic acid copolymers, poly(styrene-alt-maleic acid) (SM), poly(N-vinyl-2-pyrrolidone-alt-maleic acid) (VM) and poly(ethylene-alt-maleic acid) (EM) were used to stabilize C60 fullerene molecules in an aqueous environment by forming non-covalent complexes. Polymer conjugates were prepared by mixing a solution of fullerene in N-methylpyrrolidone (NMP) with an aqueous solution of the copolymer, followed by exhaustive dialysis against water. The molar ratios of maleic acid residues in the copolymer and C60 were 5/1 for SM and VM and 10/1 for EM. The volume ratio of NMP and water used was 1:1.2-1.6. Water-soluble complexes (composites) dried lyophilically retained solubility in NMP and water but were practically insoluble in non-polar solvents. The optical and physical properties of the preparations were characterized by UV-Vis spectroscopy, FTIR, DLS, TGA and XPS. The average diameter of the composites in water was 120-200 nm, and the ξ-potential ranged from -16 to -20 mV. The bactericidal properties of the obtained nanostructures were studied. Toxic reagents and time-consuming procedures were not used in the preparation of water-soluble C60 nanocomposites stabilized by the proposed copolymers.

5.
Lancet Haematol ; 11(7): e521-e529, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38843856

RESUMO

BACKGROUND: Given the favourable prognosis of patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma, treatment-related toxicity should be minimised. We aimed to evaluate the efficacy of 4 Gy radiotherapy given in a response-adapted approach. METHODS: We conducted a single-centre, single-arm, prospective trial at MD Anderson Cancer Center (Houston, TX, USA) of response-adapted ultra-low-dose radiotherapy. Eligible patients were 18 years or older and had newly diagnosed or relapsed Helicobacter pylori-negative gastric MALT lymphoma, with stage I-IV disease. Given the expected low toxicity profile of treatment, performance status was not an exclusion criterion. Patients received external beam photon-based radiotherapy for a total dose of 4 Gy in two fractions. Patients with a complete response to 4 Gy via endoscopy and imaging at 3-4 months were observed; patients with a partial response were re-evaluated in 6-9 months. Residual disease at 9-13 months or stable or progressive disease at any time required additional treatment with 20 Gy. The primary endpoint was gastric complete response at 1 year (second evaluation timepoint) after 4 Gy treatment. All analyses were performed as intention to treat. This trial is registered at ClinicalTrials.gov (NCT03680586) and is complete and closed to enrolment. FINDINGS: Between March 27, 2019, and Oct 12, 2021, we enrolled 24 eligible patients. The median age of participants was 67 years (IQR 58-74; range 40-85); 15 (63%) were female and nine (37%) male; 18 (75%) were White, four (17%) Asian, and two (8%) Hispanic; 20 (83%) had stage I disease, one (4%) stage II, and three (13%) stage IV. Median follow-up time was 36 months (IQR 26-42). 20 patients (83%) had a complete response to 4 Gy (16 at 3-4 months, four at 9-13 months); two patients received 20 Gy for symptomatic stable disease at 3-4 months and two for residual disease at 9-13 months; all had a complete response. The 3-year local control rate was 96% (95% CI 88-100), with one local relapse at 14 months after 4 Gy radiotherapy salvaged successfully with 20 Gy. One patient with stage IV disease had a distant relapse. The most common adverse events were grade 1 nausea (nine [38%] of 24 patients who received 4 Gy and two [50%] of four patients who received 20 Gy) and grade 1 abdominal pain (five [21%] of 24 and zero of four, respectively). No grade 3 or worse adverse events were noted, including no treatment-related deaths. INTERPRETATION: Most patients had a complete response after 4 Gy radiotherapy; all who required an additional 20 Gy had a complete response within 12 months. This response-adapted strategy could be used to select patients who would benefit from additional radiotherapy and spare others potential associated toxicity. FUNDING: National Cancer Institute.


Assuntos
Linfoma de Zona Marginal Tipo Células B , Dosagem Radioterapêutica , Neoplasias Gástricas , Humanos , Linfoma de Zona Marginal Tipo Células B/radioterapia , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Gástricas/radioterapia , Neoplasias Gástricas/patologia , Idoso , Projetos Piloto , Adulto , Estudos Prospectivos , Resultado do Tratamento , Idoso de 80 Anos ou mais
6.
Steroids ; 208: 109457, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38917951

RESUMO

Betulonic acid benzyl ester 1 has been subjected to a series of structural modifications for the purpose of new triterpenoid synthesis and evaluating for anticancer activity. The one-pot two step synthesis of 2α-(aminomethyl)betulinic acid benzyl ester derivatives 3a-f (yield 46-69 %) was achieved by the Mannich reaction of compound 1 with methyleneiminium salts, generated in situ from N,N-disubstituted bis(amino)methanes 2a-f by the action of acetyl chloride in dichloromethane, and subsequent reduction of aminomethylation products with sodium borohydride. Minor 2ß-(aminomethyl) triterpenoids 4c,d,f were also isolated (yield 6-15 %). We found, that the stereoselective reaction of triterpenoid 1 with acetylides, generated at -78 °C from alkynes in the presence of n-BuLi, has been useful and noteworthy as the key step in providing of new alkyne substituted triterpenoids - benzyl 3-alkynyl-3-deoxy-2(3),20(29)-lupadiene-28-oates or 3-deoxy-2(3)-dehydro-28-oxoallobetulin derivative. The new compounds were examined for anticancer activity against the human cell lines (MTT assay). All tested derivatives were non-toxic on human fibroblasts. The 3-(phenylethynyl)lupa-2(3),20(29)-diene 9 showed selective cytotoxicity on cervical cancer cell lines. Tumor cells death trigged by the most active compound 4f resulted from apoptotic processes. These data make the series of synthesized 2 or 3 substituted lupane derivatives as promising compounds with anticancer potential.

7.
Biochim Biophys Acta Mol Basis Dis ; 1870(7): 167317, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38909847

RESUMO

Permeabilization of the outer mitochondrial membrane is а physiological process that can allow certain molecules to pass through it, such as low molecular weight solutes required for cellular respiration. This process is also important for the development of various modes of cell death. Depending on the severity of this process, cells can die by autophagy, apoptosis, or necrosis/necroptosis. Distinct types of pores can be opened at the outer mitochondrial membrane depending on physiological or pathological stimuli, and different mechanisms can be activated in order to open these pores. In this comprehensive review, all these types of permeabilization, the mechanisms of their activation, and their role in various diseases are discussed.

8.
Diagnostics (Basel) ; 14(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38928710

RESUMO

The aim of the study was to evaluate the local status of the sclera in lattice retinal degeneration. Patients with lattice degeneration, snail-track degeneration, or horseshoe retinal breaks were included. One lesion of a single eye in each patient was captured with cross-sectional optical coherence tomography (OCT) along and across the greatest lesion dimension. The maximum height of scleral indentation was measured and compared between different lesion types and between lattice lesions with and without retinal breakage or local detachment. The correlation between the maximum height of the scleral indentation of lattice lesions and the age of the patients was calculated. Seventy-five eyes of 75 patients (44.4 ± 14.7 years; 35 males and 30 females) were included. OCT showed variable local scleral indentation in 52 out of 55 (94.5%) lattice lesions, in five out of nine (55.5%) snail-tack lesions, and in three out of eleven (27.3%) horseshoe breaks. The maximum scleral indentation within lattice lesions, snail-tack lesions, and horseshoe breaks was 227.2 ± 111.3, 22.0 ± 49.2, and 88.5 ± 48.4 µm, respectively (p < 0.001 for snail-tack lesions and horseshoe breaks compared to lattice lesions). Lattice lesions with retinal breaks and/or local retinal detachment had statistically significantly lower scleral indentation than those without (p = 0.01). The height of the scleral indentation of lattice lesions was positively correlated with patient age (r = 0.51, p = 0.03). In conclusion, scleral indentation is one of the hallmarks of lattice retinal degeneration and may be associated with a reduced risk of rhegmatogenous retinal detachment.

9.
Antioxidants (Basel) ; 13(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38929158

RESUMO

Protein persulfidation is a thiol-based oxidative posttranslational modification (oxiPTM) that involves the modification of susceptible cysteine thiol groups present in peptides and proteins through hydrogen sulfide (H2S), thus affecting their function. Using sweet pepper (Capsicum annuum L.) fruits as a model material at different stages of ripening (immature green and ripe red), endogenous persulfidated proteins (persulfidome) were labeled using the dimedone switch method and identified using liquid chromatography and mass spectrometry analysis (LC-MS/MS). A total of 891 persulfidated proteins were found in pepper fruits, either immature green or ripe red. Among these, 370 proteins were exclusively present in green pepper, 237 proteins were exclusively present in red pepper, and 284 proteins were shared between both stages of ripening. A comparative analysis of the pepper persulfidome with that described in Arabidopsis leaves allowed the identification of 25% of common proteins. Among these proteins, glutathione reductase (GR) and leucine aminopeptidase (LAP) were selected to evaluate the effect of persulfidation using an in vitro approach. GR activity was unaffected, whereas LAP activity increased by 3-fold after persulfidation. Furthermore, this effect was reverted through treatment with dithiothreitol (DTT). To our knowledge, this is the first persulfidome described in fruits, which opens new avenues to study H2S metabolism. Additionally, the results obtained lead us to hypothesize that LAP could be involved in glutathione (GSH) recycling in pepper fruits.

10.
Minerva Urol Nephrol ; 76(3): 312-319, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38920011

RESUMO

BACKGROUND: The aim is to evaluate factors impacting operating time (OT) during robot-assisted radical prostatectomy (RARP) with or without extended pelvic lymph node dissection (ePLND) for prostate cancer. METHODS: Overall, 1289 patients underwent RARP from January 2013 to December 2021. ePLND was performed in 825 cases. Factors potentially associated with OT variations were assessed. Three low-volume (LVS) and two high-volume surgeons (HVS) performed the procedures. A linear regression model was computed to assess associations with OT variations. RESULTS: When RARP was performed by HVS an OT decrease was observed independently by significant clinical (Body Mass Index [BMI]; prostate volume [PV]) and anatomical/perioperative features (prostate weight [PW]; intraoperative blood loss [BL]) both in clinical (change in OT: -42.979 minutes; 95% CI: -51.789; -34.169; P<0.0001) and anatomical/perioperative models (change in OT: -40.020 minutes; 95% CI: -48.494; -31.587; P<0.0001). A decreased OT was observed in clinical (change in OT: -27.656 minutes; 95% CI: -33.449; -21.864; P<0.0001) and anatomical/perioperative (change in OT: -24.935 minutes; 95% CI: -30.562; -19.308; P<0.0001) models also in case of RARP with ePLND performed by HVS, independently by BMI, PV, PSA as well as for PW, seminal vesicle invasion, positive surgical margins, and BL. CONCLUSIONS: In a tertiary academic referral center, OT decreased when RARP was performed by HVS, independently of adverse clinical and anatomical/perioperative factors. Available OT loads can be planned to optimize waiting lists, teaching tasks, operative costs, and surgeon's volume.


Assuntos
Excisão de Linfonodo , Duração da Cirurgia , Prostatectomia , Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Humanos , Prostatectomia/métodos , Masculino , Procedimentos Cirúrgicos Robóticos/métodos , Pessoa de Meia-Idade , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Idoso , Excisão de Linfonodo/métodos , Excisão de Linfonodo/estatística & dados numéricos , Cirurgiões/estatística & dados numéricos , Estudos Retrospectivos
11.
Minerva Anestesiol ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922284

RESUMO

INTRODUCTION: Decision-making about organ donation (OD) is influenced by interrelated cognitive and non-cognitive factors. The identification of these factors in the general population and among healthcare professionals (HCP) in Italy are key ethical and scientific requirements to inform targeted communication and policy-making interventions, and to promote decision-making processes that are truly informed. EVIDENCE ACQUISITION: A systematic review of articles published between January 1, 1999, and January 31, 2024 was performed by searching four databases using these terms: "organ donation" AND (attitude OR opinion OR knowledge OR awareness OR intention OR beliefs OR norms OR perception) AND (Italy OR Italian). The reference sections of included articles were scrutinized for additional references. EVIDENCE SYNTHESIS: Most respondents (lay citizens and HCPs) were in favor of OD, but many (mainly but not exclusively lay citizens) would not authorize OD in the event of death of a family member. Lack of knowledge about OD and the gap between demand and supply of organs, fear of body mutilation, doubts about the criteria for brain death diagnosis, doubts about the wishes of the deceased family member, and distrust towards medical doctors and the healthcare system were the most commonly reported reasons, confirming that cognitive and non-cognitive factors are at play. CONCLUSIONS: The majority of the Italian population supports OD, but cognitive and non-cognitive barriers are present even among HCPs. Communication campaigns, encouraging family discussions about OD, providing better education for HCPs (including medical and nursing students), and making it easier to sign OD cards may promote informed decision-making and possibly increase consent rates.

12.
Biomolecules ; 14(6)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38927110

RESUMO

This work describes a novel route for phospholipid fatty acid remodeling involving the monounsaturated fatty acid palmitoleic acid. When administered to human monocytes, palmitoleic acid rapidly incorporates into membrane phospholipids, notably into phosphatidylcholine (PC). In resting cells, palmitoleic acid remains within the phospholipid pools where it was initially incorporated, showing no further movement. However, stimulation of the human monocytes with either receptor-directed (opsonized zymosan) or soluble (calcium ionophore A23187) agonists results in the rapid transfer of palmitoleic acid moieties from PC to phosphatidylinositol (PI). This is due to the activation of a coenzyme A-dependent remodeling route involving two different phospholipase A2 enzymes that act on different substrates to generate free palmitoleic acid and lysoPI acceptors. The stimulated enrichment of specific PI molecular species with palmitoleic acid unveils a hitherto-unrecognized pathway for lipid turnover in human monocytes which may play a role in regulating lipid signaling during innate immune activation.


Assuntos
Ácidos Graxos Monoinsaturados , Monócitos , Fosfatidilcolinas , Fosfatidilinositóis , Humanos , Monócitos/metabolismo , Monócitos/efeitos dos fármacos , Ácidos Graxos Monoinsaturados/metabolismo , Ácidos Graxos Monoinsaturados/farmacologia , Fosfatidilcolinas/metabolismo , Fosfatidilinositóis/metabolismo
13.
Neurol Neuroimmunol Neuroinflamm ; 11(4): e200271, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38896808

RESUMO

BACKGROUND AND OBJECTIVES: A CSF-in gradient in cortical and thalamic gray matter (GM) damage has been found in multiple sclerosis (MS). We concomitantly explored the patterns of cortical, thalamic, and caudate microstructural abnormalities at progressive distances from CSF using a multiparametric MRI approach. METHODS: For this cross-sectional study, from 3T 3D T1-weighted scans, we sampled cortical layers at 25%-50%-75% depths from pial surface and thalamic and caudate bands at 2-3-4 voxels from the ventricular-GM interface. Using linear mixed models, we tested between-group comparisons of magnetization transfer ratio (MTR) and R2* layer-specific z-scores, CSF-in across-layer z-score changes, and their correlations with clinical (disease duration and disability) and structural (focal lesions, brain, and choroid plexus volume) MRI measures. RESULTS: We enrolled 52 patients with MS (33 relapsing-remitting [RRMS], 19 progressive [PMS], mean age: 46.4 years, median disease duration: 15.1 years, median: EDSS 2.0) and 70 controls (mean age 41.5 ± 12.8). Compared with controls, RRMS showed lower MTR values in the outer and middle cortical layers (false-discovery rate [FDR]-p ≤ 0.025) and lower R2* values in all 3 cortical layers (FDR-p ≤ 0.016). PMS had lower MTR values in the outer and middle cortical (FDR-p ≤ 0.016) and thalamic (FDR-p ≤ 0.048) layers, and in the outer caudate layer (FDR-p = 0.024). They showed lower R2* values in the outer cortical layer (FDR-p = 0.003) and in the outer thalamic layer (FDR-p = 0.046) and higher R2* values in all 3 caudate layers (FDR-p ≤ 0.031). Both RRMS and PMS had a gradient of damage, with lower values closer to the CSF, for cortical (FDR-p ≤ 0.002) and thalamic (FDR-p ≤ 0.042) MTR. PMS showed a gradient of damage for cortical R2* (FDR-p = 0.005), thalamic R2* (FDR-p = 0.004), and caudate MTR (FDR-p ≤ 0.013). Lower MTR and R2* of outer cortical, thalamic, and caudate layers and steeper gradient of damage toward the CSF were significantly associated with older age, higher T2-hyperintense white matter lesion volume, higher thalamic lesion volume, and lower brain volume (ß ≥ 0.08, all FDR-p ≤ 0.040). Lower MTR of outer caudate layer was associated with more severe disability (ß = -0.26, FDR-p = 0.040). No correlations with choroid plexus volume were found. DISCUSSION: CSF-in damage gradients are heterogeneous among different GM regions and through MS course, possibly reflecting different dynamics of demyelination and iron loss/accumulation.


Assuntos
Córtex Cerebral , Substância Cinzenta , Esclerose Múltipla Recidivante-Remitente , Tálamo , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Adulto , Estudos Transversais , Substância Cinzenta/patologia , Substância Cinzenta/diagnóstico por imagem , Córtex Cerebral/patologia , Córtex Cerebral/diagnóstico por imagem , Tálamo/patologia , Tálamo/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano , Esclerose Múltipla Recidivante-Remitente/patologia , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Esclerose Múltipla Crônica Progressiva/líquido cefalorraquidiano , Esclerose Múltipla Crônica Progressiva/diagnóstico por imagem , Esclerose Múltipla Crônica Progressiva/patologia , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética Multiparamétrica , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/patologia , Esclerose Múltipla/diagnóstico por imagem , Núcleo Caudado/patologia , Núcleo Caudado/diagnóstico por imagem
14.
Front Endocrinol (Lausanne) ; 15: 1296886, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828417

RESUMO

Introduction: The dysregulation of cell fate toward osteoprecursor cells associated with most GNAS-based disorders may lead to episodic de novo extraskeletal or ectopic bone formation in subcutaneous tissues. The bony lesion distribution suggests the involvement of abnormal differentiation of mesenchymal stem cells (MSCs) and/or more committed precursor cells. Data from transgenic mice support the concept that GNAS is a crucial factor in regulating lineage switching between osteoblasts (OBs) and adipocyte fates. The mosaic nature of heterotopic bone lesions suggests that GNAS genetic defects provide a sensitized background for ectopic osteodifferentiation, but the underlying molecular mechanism remains largely unknown. Methods: The effect of GNAS silencing in the presence and/or absence of osteoblastic stimuli was evaluated in the human L88/5 MSC line during osteodifferentiation. A comparison of the data obtained with data coming from a bony lesion from a GNAS-mutated patient was also provided. Results: Our study adds some dowels to the current fragmented notions about the role of GNAS during osteoblastic differentiation, such as the premature transition of immature OBs into osteocytes and the characterization of the differences in the deposed bone matrix. Conclusion: We demonstrated that our cell model partially replicates the in vivo behavior results, resulting in an applicable human model to elucidate the pathophysiology of ectopic bone formation in GNAS-based disorders.


Assuntos
Diferenciação Celular , Cromograninas , Subunidades alfa Gs de Proteínas de Ligação ao GTP , Células-Tronco Mesenquimais , Osteoblastos , Osteogênese , Humanos , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Cromograninas/genética , Diferenciação Celular/genética , Osteogênese/genética , Osteoblastos/metabolismo , Osteoblastos/citologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Inativação Gênica , Linhagem Celular
15.
Artigo em Inglês | MEDLINE | ID: mdl-38829958

RESUMO

INTRODUCTION: Recent studies have identified a critical role for stromal-immune cell interactions in immunity and immune tolerance. Transcriptomic profiling has implicated stromal cells in immune-mediated disorders including the two common forms of inflammatory bowel disease (IBD), Crohn's disease (CD) and ulcerative colitis (UC). Stromal-immune interactions may edify inflammatory state and the development of IBD-related complications such as fibrosis; yet the lack of protein markers has hampered studying stromal-immune perturbation. METHODS: In this study, we designed a 40-color spectral flow cytometry assay to characterize hematopoietic and nonhematopoietic cells in intestinal biopsies and matched blood samples from patients with CD or UC. RESULTS: We identified circulating stromal-like cells that are significantly more abundant in IBD blood samples than in healthy controls. Those cells expressed podoplanin (PDPN), a commonly used marker for fibroblasts, and they were associated with activated and memory T and B cells, and altered NK cell, monocyte, and macrophage populations. PDPN+ cells in the blood correlated with PDPN+ cells in the colon. Principal component analysis distinctly separated healthy blood samples from IBD blood samples, with stromal-like cells and B cell subtypes dominating the IBD signature; Pearson correlation detected an association between PDPN+ stromal-like cells and B cell populations in IBD blood and gut biopsies. DISCUSSION: These observations suggest that PDPN+ cells in the blood may serve as a biomarker of IBD. Understanding the relationship between stromal cells and immune cells in the intestine and the blood may provide a window into disease pathogenesis and insight into therapeutic targets for IBD.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38831186

RESUMO

Adipose tissue plays an essential role in systemic metabolism with white adipose tissue (WAT) making up most of the tissue and being involved in the regulation of energy homeostasis, and brown and beige adipose tissue (BAT) exhibiting thermogenic activity. There is promise in the conversion of white adipocytes into beige ones as a therapeutic potential to control and enhance systemic metabolism, but it is difficult to maintain this transformation in vivo because we do not fully understand the mechanism of conversion. In this study, we applied atomic force microscopy (AFM) to characterize beige or white adipocytes during the process of differentiation for morphology, roughness, adhesion, and elasticity at different time points. As cells differentiated to white and beige adipocytes, they exhibited morphological changes as they lipid loaded, transitioning from flattened elongated cells to a rounded shape indicating adipogenesis. While there was an initial decrease in elasticity for both beige and white adipocytes, white adipocytes exhibited a higher elasticity than beige adipocytes at all time points. Beige and white adipogenesis exhibited a decrease in adhesion energy compared to preadipocytes, yet at day 12, white adipocytes had a significant increase in adhesion energy compared to beige adipocytes. This work shows significant differences in the mechanical properties of white vs. beige adipocytes during differentiation. Results from this study contribute to a better understanding of the differentiation of adipocytes which are vital to the therapeutic induction, engineered models, and maintenance of beige adipocytes as a potential approach for enhancing systemic metabolism.

17.
Nucleic Acids Res ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38832628

RESUMO

Nucleoid-associated proteins (NAPs) play central roles in bacterial chromosome organization and DNA processes. The Escherichia coli YejK protein is a highly abundant, yet poorly understood NAP. YejK proteins are conserved among Gram-negative bacteria but show no homology to any previously characterized DNA-binding protein. Hence, how YejK binds DNA is unknown. To gain insight into YejK structure and its DNA binding mechanism we performed biochemical and structural analyses on the E. coli YejK protein. Biochemical assays demonstrate that, unlike many NAPs, YejK does not show a preference for AT-rich DNA and binds non-sequence specifically. A crystal structure revealed YejK adopts a novel fold comprised of two domains. Strikingly, each of the domains harbors an extended arm that mediates dimerization, creating an asymmetric clamp with a 30 Å diameter pore. The lining of the pore is electropositive and mutagenesis combined with fluorescence polarization assays support DNA binding within the pore. Finally, our biochemical analyses on truncated YejK proteins suggest a mechanism for YejK clamp loading. Thus, these data reveal YejK contains a newly described DNA-binding motif that functions as a novel clamp.

18.
JAMA Ophthalmol ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842822

RESUMO

Importance: National estimates regarding the frequency of presentations and patterns of care for eye pain are unknown. This information could guide research and clinical efforts to optimize outcomes. Objective: To estimate eye pain visits in the US in the outpatient and emergency department (ED) settings. Design, Setting, and Participants: This retrospective cross-sectional study of National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey data (2008-2019) analyzed a population-based sample of visits to outpatient clinics and EDs. The sample consisted of patients presenting with eye pain. Data were analyzed from September 2023 to April 2024. Main Outcomes and Measures: Weighted sample data estimated outpatient and ED eye pain presentations including patient and clinician characteristics, diagnoses (International Statistical Classification of Diseases and Related Health Problems, Tenth Revision [ICD-10]), and disposition. Results: From 2008 through 2019, 4.6 million (95% CI, 3.9 million to 5.3 million) outpatient and 1.0 million (95% CI, 0.8 million to 1.1 million) ED eye pain visits occurred annually. Patients were predominantly women (63.2% [95% CI, 59.4%-67.0%]) and older than 60 years (46.6% [95% CI, 42.4%-51.0%]) in the outpatient setting. Patients presenting to the ED were more often men (51.8% [95% CI, 48.7%-55.0%]) and aged younger than 45 years (aged <15 years: 16.4% [95% CI, 13.9%-18.8%]; 15-24 years: 19.2% [95% CI, 16.6%-21.7%]; and 25-44 years: 35.6% [95% CI, 32.7%-38.5%]). In nearly half of outpatient eye pain visits, the major problem was classified as nonacute (2.0 million [95% CI, 1.6 million to 2.3 million]). Eye pain was the primary reason for the visit (RFV) in 42.0% (95% CI, 37.8%-46.2%) of outpatient visits and 66.9% (95% CI, 62.9%-70.9%) of ED eye pain visits. It was the only RFV in 18.3% (95% CI, 15.0%-21.7%) of outpatient and 32.7% (95% CI, 29.0%-36.4%) of ED eye pain encounters. Ophthalmologists evaluated the largest number of outpatient visits (45.3% [95% CI, 38.8%-51.7%). The primary diagnosis was non-vision threatening for most outpatient (78.5% [95% CI, 56.8%-100%]) and ED (69.9% [95% CI, 62.1%-77.7%]) visits when eye pain was the primary RFV. Additional follow-up was scheduled in 89.4% (95% CI, 86.2%-92.6%) of visits. Conclusions and Relevance: More than 5 million eye pain visits occur annually; the largest percentage are outpatient with ophthalmologists. Most diagnoses were non-vision threatening in both the outpatient and ED setting and resulted in additional care. Expanding therapeutic approaches to treat the causes of eye pain may reduce the burden on the health care system and optimize outcomes.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38851879

RESUMO

OBJECTIVE: To evaluate the effectiveness of long-term, personalized, supervised exercise therapy on functional ability compared with usual care in people with axial spondyloarthritis (axSpA) and severe functional limitations. METHODS: Participants were randomly 1:1 assigned to the intervention(maximal 64 sessions, with 14 additional optional sessions of supervised active exercise therapy(e.g. aerobic and muscle strengthening) with individualized goal-setting, education and self-management regarding physical activity) or usual care(care determined by clinician(s) and participants themselves). Primary end point was the change in the Patient-Specific Complaints activity ranked 1 (PSC1 (0-10)) at 52 weeks. Secondary endpoints were the PSC activities ranked 2 and 3, the Bath Ankylosing Spondylitis Functional Index, 6-min walk test, Patient Reported Outcome Measurement Information System-Physical Function-10 and the Short Form-36 Physical and Mental Component Summary Score (SF-36 PCS and MCS). Statistical comparisons comprised independent student t-tests and linear mixed models, based on intention-to-treat. RESULTS: 214 participants(49% female, age 52 (SD 12) years), were randomized to the intervention (n = 110) or usual care (N = 104) group. In the intervention group 93% started treatment, using on average 40.5 sessions (SD 15.1). At 52 weeks, the difference in change in PSC1 between groups favored the intervention group (mean difference [95% CI]; -1.8 [-2.4 to -1.2]). additionally, all secondary outcomes, except the SF-36 MSC, showed significantly greater improvements in the intervention group with effect sizes ranging from 0.4-0.7. CONCLUSION: Long-term, supervised exercise therapy proved more effective than usual care in improving functional disability and physical quality of life in people with axSpA and severe functional limitations. CLINICAL TRIAL REGISTER NUMBER: Netherlands Trial Register NL8238, included in the International Clinical Trial Registry Platform (ICTRP) (https://trialsearch.who.int/Trial2.aspx?TrialID=NL8238).

20.
Eur J Cancer ; 207: 114148, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38834015

RESUMO

BACKGROUND: Cancer patients with autoimmune disease have been excluded from randomized trials of immune checkpoint blockers (ICBs). We conducted a systematic review of observational studies and uncontrolled trials including cancer patients with pre-existing autoimmune disease who received ICBs. METHODS: We searched 5 electronic databases through November 2023. Study selection, data collection, and quality assessment were performed independently by 2 investigators. We performed a meta-analysis to pool incidence of immune-related adverse events (irAEs), including de novo events and flares of existing autoimmune disease, hospitalizations due to irAEs, as well as deaths. RESULTS: A total of 95 studies were included (23,897 patients with cancer and preexisting autoimmune disease). The most common cancer evaluated was lung cancer (30.7 %) followed by skin cancer (15.7 %). Patients with autoimmune disease were more likely to report irAEs compared to patients without autoimmune disease (relative risk 1.3, 95 % CI 1.0 to 1.6). The pooled occurrence rate of any irAEs (flares or de novo) was 61 % (95 % CI 54 % to 68 %); that of flares was 36 % (95 % CI 30 % to 43 %), and that of de novo irAEs was 23 % (95 % CI 16 % to 30 %). Flares were mild (grade <3) in half of cases and more commonly reported in patients with psoriasis/psoriatic arthritis (39 %), inflammatory bowel disease (37 %), and rheumatoid arthritis (36 %). 32 % of the patients with irAEs required hospitalization and treatment of irAEs included corticosteroids in 72 % of the cases. The irAEs mortality rate was 0.07 %. There were no statistically significant differences in cancer response to ICBs between patients with and without autoimmune disease. CONCLUSIONS: Although more patients with pre-existing autoimmune disease had irAEs, these were mild and managed with corticosteroids in most cases, with no impact on cancer response. These results suggest that ICBs can be used in these patients, but careful monitoring is required, as over a third of the patients will experience a flare of their autoimmune disease and/or require hospitalization. These findings provide a crucial foundation for oncologists to refine their monitoring and management strategies, ensuring that the benefits of ICB therapy are maximized while minimizing its risks.

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