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1.
Cell ; 179(6): 1306-1318.e18, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31761535

RESUMO

Cells have evolved complex mechanisms to maintain protein homeostasis, such as the UPRER, which are strongly associated with several diseases and the aging process. We performed a whole-genome CRISPR-based knockout (KO) screen to identify genes important for cells to survive ER-based protein misfolding stress. We identified the cell-surface hyaluronidase (HAase), Transmembrane Protein 2 (TMEM2), as a potent modulator of ER stress resistance. The breakdown of the glycosaminoglycan, hyaluronan (HA), by TMEM2 within the extracellular matrix (ECM) altered ER stress resistance independent of canonical UPRER pathways but dependent upon the cell-surface receptor, CD44, a putative HA receptor, and the MAPK cell-signaling components, ERK and p38. Last, and most surprisingly, ectopic expression of human TMEM2 in C. elegans protected animals from ER stress and increased both longevity and pathogen resistance independent of canonical UPRER activation but dependent on the ERK ortholog mpk-1 and the p38 ortholog pmk-1.


Assuntos
Caenorhabditis elegans/fisiologia , Retículo Endoplasmático/metabolismo , Hialuronoglucosaminidase/metabolismo , Longevidade/fisiologia , Proteínas de Membrana/metabolismo , Resposta a Proteínas não Dobradas , Animais , Caenorhabditis elegans/imunologia , Linhagem Celular , Proliferação de Células , Resistência à Doença , Estresse do Retículo Endoplasmático , Fibroblastos/metabolismo , Humanos , Imunidade Inata , Modelos Biológicos , Peso Molecular , Transdução de Sinais
2.
Nucleic Acids Res ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38966985

RESUMO

The TOPOVIL complex catalyzes the formation of DNA double strand breaks (DSB) that initiate meiotic homologous recombination, an essential step for chromosome segregation and genetic diversity during gamete production. TOPOVIL is composed of two subunits (SPO11 and TOPOVIBL) and is evolutionarily related to the archaeal TopoVI topoisomerase complex. SPO11 is the TopoVIA subunit orthologue and carries the DSB formation catalytic activity. TOPOVIBL shares homology with the TopoVIB ATPase subunit. TOPOVIBL is essential for meiotic DSB formation, but its molecular function remains elusive, partly due to the lack of biochemical studies. Here, we purified TOPOVIBLΔC25 and characterized its structure and mode of action in vitro. Our structural analysis revealed that TOPOVIBLΔC25 adopts a dynamic conformation in solution and our biochemical study showed that the protein remains monomeric upon incubation with ATP, which correlates with the absence of ATP binding. Moreover, TOPOVIBLΔC25 interacted with DNA, with a preference for some geometries, suggesting that TOPOVIBL senses specific DNA architectures. Altogether, our study identified specific TOPOVIBL features that might help to explain how TOPOVIL function evolved toward a DSB formation activity in meiosis.

3.
Proc Natl Acad Sci U S A ; 119(33): e2114734119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35947615

RESUMO

The kidney-specific gene UMOD encodes for uromodulin, the most abundant protein excreted in normal urine. Rare large-effect variants in UMOD cause autosomal dominant tubulointerstitial kidney disease (ADTKD), while common low-impact variants strongly associate with kidney function and the risk of chronic kidney disease (CKD) in the general population. It is unknown whether intermediate-effect variants in UMOD contribute to CKD. Here, candidate intermediate-effect UMOD variants were identified using large-population and ADTKD cohorts. Biological and phenotypical effects were investigated using cell models, in silico simulations, patient samples, and international databases and biobanks. Eight UMOD missense variants reported in ADTKD are present in the Genome Aggregation Database (gnomAD), with minor allele frequency (MAF) ranging from 10-5 to 10-3. Among them, the missense variant p.Thr62Pro is detected in ∼1/1,000 individuals of European ancestry, shows incomplete penetrance but a high genetic load in familial clusters of CKD, and is associated with kidney failure in the 100,000 Genomes Project (odds ratio [OR] = 3.99 [1.84 to 8.98]) and the UK Biobank (OR = 4.12 [1.32 to 12.85). Compared with canonical ADTKD mutations, the p.Thr62Pro carriers displayed reduced disease severity, with slower progression of CKD and an intermediate reduction of urinary uromodulin levels, in line with an intermediate trafficking defect in vitro and modest induction of endoplasmic reticulum (ER) stress. Identification of an intermediate-effect UMOD variant completes the spectrum of UMOD-associated kidney diseases and provides insights into the mechanisms of ADTKD and the genetic architecture of CKD.


Assuntos
Insuficiência Renal Crônica , Uromodulina , Heterozigoto , Humanos , Mutação , Insuficiência Renal Crônica/genética , Uromodulina/genética
4.
Nature ; 559(7712): 77-82, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29942075

RESUMO

Developing adaptive materials with geometries that change in response to external stimuli provides fundamental insights into the links between the physical forces involved and the resultant morphologies and creates a foundation for technologically relevant dynamic systems1,2. In particular, reconfigurable surface topography as a means to control interfacial properties3 has recently been explored using responsive gels4, shape-memory polymers5, liquid crystals6-8 and hybrid composites9-14, including magnetically active slippery surfaces12-14. However, these designs exhibit a limited range of topographical changes and thus a restricted scope of function. Here we introduce a hierarchical magneto-responsive composite surface, made by infiltrating a ferrofluid into a microstructured matrix (termed ferrofluid-containing liquid-infused porous surfaces, or FLIPS). We demonstrate various topographical reconfigurations at multiple length scales and a broad range of associated emergent behaviours. An applied magnetic-field gradient induces the movement of magnetic nanoparticles suspended in the ferrofluid, which leads to microscale flow of the ferrofluid first above and then within the microstructured surface. This redistribution changes the initially smooth surface of the ferrofluid (which is immobilized by the porous matrix through capillary forces) into various multiscale hierarchical topographies shaped by the size, arrangement and orientation of the confining microstructures in the magnetic field. We analyse the spatial and temporal dynamics of these reconfigurations theoretically and experimentally as a function of the balance between capillary and magnetic pressures15-19 and of the geometric anisotropy of the FLIPS system. Several interesting functions at three different length scales are demonstrated: self-assembly of colloidal particles at the micrometre scale; regulated flow of liquid droplets at the millimetre scale; and switchable adhesion and friction, liquid pumping and removal of biofilms at the centimetre scale. We envision that FLIPS could be used as part of integrated control systems for the manipulation and transport of matter, thermal management, microfluidics and fouling-release materials.

5.
Sensors (Basel) ; 24(6)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38544167

RESUMO

There is a growing interest in wearable inertial sensors to monitor and analyze the movements of pregnant women. The noninvasive and discrete nature of these sensors, integrated into devices accumulating large datasets, offers a unique opportunity to study the dynamic changes in movement patterns during the rapid physical transformations induced by pregnancy. However, the final cut of the third trimester of pregnancy, particularly the first stage of labor up to delivery, remains underexplored. The growing popularity of "walking epidural", a neuraxial analgesia method allowing motor function preservation, ambulation, and free movement throughout labor and during delivery, opens new opportunities to study the biomechanics of labor using inertial sensors. Critical research gaps exist in parturient fall prediction and detection during walking epidural and understanding pain dynamics during labor, particularly in the presence of pelvic girdle pain. The analysis of fetal descent, upright positions, and their relationship with dynamic pelvic movements facilitated by walking during labor is another area where inertial sensors can play an interesting role. Moreover, as contemporary obstetrics advocate for less restricted or non-restricted movements during labor, the role of inertial sensors in objectively measuring the quantity and quality of women's movements becomes increasingly important. This includes studying the impact of epidural analgesia on maternal mobility, walking patterns, and associated obstetrical outcomes. In this paper, the potential use of wearable inertial sensors for gait analysis in the first stage of labor is discussed.


Assuntos
Analgesia Epidural , Trabalho de Parto , Dispositivos Eletrônicos Vestíveis , Gravidez , Feminino , Humanos , Analgesia Epidural/métodos , Caminhada , Dor
6.
Nephrol Dial Transplant ; 38(8): 1848-1856, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-36477902

RESUMO

BACKGROUND: Nephrosclerosis is one of the histopathological consequences of severe or malignant hypertension (MH), some of the pathophysiology of which has been extrapolated from essential polygenetic arterial hypertension. Despite our recent description of unsuspected ciliopathies with MH, causes of MH in young patients with severe renal impairment are poorly understood. METHODS: To refine and better describe the MH phenotype, we studied clinical and prognostic factors in young patients receiving a kidney biopsy following their first episode of MH. Patients were identified retrospectively and prospectively from eight centres over a 35-year period (1985-2020). Keywords were used to retrospectively enrol patients irrespective of lesions found on renal biopsy. RESULTS: A total of 114 patients were included, 77 (67%) of whom were men, average age 34 years, 35% Caucasian and 34% African origin. An isolated clinical diagnosis of severe nephrosclerosis was suggested in only 52% of cases, with 24% primary glomerulopathies. Only 7% of patients had normal renal function at diagnosis, 25% required emergency dialysis and 21% were eventually transplanted. Mortality was 1% at the last follow-up. Independent prognostic factors significantly associated with renal prognosis (6-month dialysis) and predictive of end-stage renal disease were serum creatinine on admission {odds ratio [OR] 1.56 [95% confidence interval (CI) 1.34-1.96], P < .001} and renal fibrosis >30% [OR 10.70 (95% CI 1.53-112.03), P = .03]. Astonishingly, the presence of any thrombotic microangiopathy lesion on renal biopsy was an independent, protective factor [OR 0.14 (95% CI 0.02-0.60), P = .01]. The histopathological hallmark of nephrosclerosis was found alone in only 52% of study patients, regardless of ethnicity. CONCLUSIONS: This suggests that kidney biopsy might be beneficial in young patients with MH.


Assuntos
Hipertensão Maligna , Hipertensão , Nefroesclerose , Humanos , Nefroesclerose/complicações , Hipertensão Maligna/complicações , Hipertensão Maligna/epidemiologia , Estudos Retrospectivos , Diálise Renal/efeitos adversos , Rim , Hipertensão Essencial , Biópsia , Hipertensão/complicações , Hipertensão/patologia
7.
Brain ; 145(8): 2755-2768, 2022 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-35485527

RESUMO

Abnormal accumulation of microtubule-associated protein tau (τ) is a characteristic feature of atypical parkinsonisms with tauopathies, such as progressive supranuclear palsy and corticobasal degeneration. However, pathological τ has also been observed in α-synucleinopathies like Parkinson's disease and multiple system atrophy. Based on the involvement of the peripheral nervous system in several neurodegenerative diseases, we characterized and compared τ expression in skin biopsies of patients clinically diagnosed with Parkinson's disease, multiple system atrophy, progressive supranuclear palsy and corticobasal degeneration and in healthy control subjects. In all groups, τ protein was detected along both somatosensory and autonomic nerve fibres in the epidermis and dermis by immunofluorescence. We found by western blot the presence of mainly two different bands at 55 and 70 kDa, co-migrating with 0N4R/1N3R and 2N4R isoforms, respectively. At the RNA level, the main transcript variants were 2N and 4R, and both were more expressed in progressive supranuclear palsy/corticobasal degeneration by real-time PCR. Enzyme-linked immunosorbent assay demonstrated significantly higher levels of total τ protein in skin lysates of progressive supranuclear palsy/corticobasal degeneration compared to the other groups. Multivariate regression analysis and receiver operating characteristics curve analysis of τ amount at both sites showed a clinical association with tauopathies diagnosis and high diagnostic value for progressive supranuclear palsy/corticobasal degeneration versus Parkinson's disease (sensitivity 90%, specificity 69%) and progressive supranuclear palsy/corticobasal degeneration versus multiple system atrophy (sensitivity 90%, specificity 86%). τ protein increase correlated with cognitive impairment in progressive supranuclear palsy/corticobasal degeneration. This study is a comprehensive characterization of τ in the human cutaneous peripheral nervous system in physiological and pathological conditions. The differential expression of τ, both at transcript and protein levels, suggests that skin biopsy, an easily accessible and minimally invasive exam, can help in discriminating among different neurodegenerative diseases.


Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Paralisia Supranuclear Progressiva , Sinucleinopatias , Tauopatias , Biópsia , Humanos , Proteínas tau
8.
Bioorg Chem ; 134: 106456, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36913879

RESUMO

The 2-(3-pyridyl)oxazolo[5,4-f]quinoxalines CD-07 and FL-291 are ATP-competitive GSK-3 kinase inhibitors. Here, we investigated the impact of FL-291 on neuroblastoma cell viability and showed that treatment at 10 µM (i.e. ∼500 times the IC50 against the GSK-3 isoforms) has no significant effect on the viability of NSC-34 motoneuron-like cells. A study performed on primary neurons (non-cancer cells) led to similar results. The structures co-crystallized with GSK-3ß revealed similar binding modes for FL-291 and CD-07, with their hinge-oriented planar tricyclic system. Both GSK isoforms show the same orientations for the amino acids at the binding pocket except for Phe130 (α) and Phe67 (ß), leading to a larger pocket on the opposite side of the hinge region for the α isoform. Calculations of the thermodynamic properties of the binding pockets highlighted the required features of potential ligands; these should have a hydrophobic core (which could be larger in the case of GSK-3ß) surrounded by polar areas (a little more polar in the case of GSK-3α). A library of 27 analogs of FL-291 and CD-07 was thus designed and synthesized by taking advantage of this hypothesis. While the introduction of substituents at different positions of the pyridine ring, the replacement of the pyridine by other heterocyclic moieties, or the replacement of the quinoxaline ring by a quinoline moiety did not lead to any improvement, the replacement of the N-(thio)morpholino of FL-291/CD-07 by a slightly more polar N-thiazolidino led to a significant result. Indeed, the new inhibitor MH-124 showed clear selectivity for the α isoform, with IC50 values of 17 nM and 239 nM on GSK-3α and GSK-3ß, respectively. Finally, the efficacy of MH-124 was evaluated on two glioblastoma cell lines. Although MH-124 alone did not have a significant impact on cell survival, its addition to temozolomide (TMZ) significantly reduced the TMZ IC50 values on the cells tested. The use of the Bliss model allowed a synergy to be evidenced at certain concentrations.


Assuntos
Glioblastoma , Quinase 3 da Glicogênio Sintase , Humanos , Temozolomida , Glicogênio Sintase Quinase 3 beta , Quinoxalinas/farmacologia , Proteínas Serina-Treonina Quinases , Isoformas de Proteínas
9.
Bioorg Chem ; 133: 106383, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36764231

RESUMO

Tyrosine protein kinases (TKs) have been proved to play substantial roles on many cellular processes and their overexpression tend to be found in various types of cancers. Therefore, over recent decades, numerous tyrosine protein kinase inhibitors particularly epidermal growth factor receptor (EGFR) inhibitors have been introduced to treat cancer. Present study describes a novel series of imidazo[1,2-a]quinazolines 18 as potential -inhibitors. These imidazoquinazolines (18a and 18o, in particular) had great anti-proliferative activities with IC50 values in the micromolar (µM) range against PC3, HepG2, HeLa, and MDA-MB-231 comparing with Erlotinib as reference marketed drug. Further evaluations on some derivatives revealed their potential to induce apoptotic cell death and cell growth arrest at G0 phase of the cell cycle. Afterwards, the kinase assay on the most potent compounds 18a and 18o demonstrated their inhibitory potencies and selectivity toward EGFR (with EGFR-IC50 values of 82.0 µM and 12.3 µM, respectively). Additionally, western blot analysis on these compounds 18a and 18o exhibited that they inhibited the phosphorylation of EGFR and its downstream molecule extracellular signal-regulated kinase (ERK1/2). However, the level of B-Actin phosphorylation was not changed. Finally, density functional theory calculations, docking study, and independent gradient model (IGM) were performed to illustrate the structure-activity relationship (SAR) and to assess the interactions between proteins and ligands. The results of molecular docking studies had great agreement with the obtained EGFR inhibitory results through in vitro evaluations.


Assuntos
Antineoplásicos , Quinazolinas , Isótopos de Oxigênio/farmacologia , Simulação de Acoplamento Molecular , Quinazolinas/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB , Relação Estrutura-Atividade , Proliferação de Células , Inibidores de Proteínas Quinases
10.
Clin Rehabil ; 37(12): 1670-1683, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37350084

RESUMO

OBJECTIVE: This study presents the walking abilities of participants fitted with transfemoral bone-anchored prostheses using a total of 14 gait parameters. DESIGN: Two-centre retrospective cross-sectional comparative study. SETTING: Research facilities equipped with tridimensional motion capture systems. PARTICIPANTS: Two control arms included eight able-bodied participants arm (54 ± 9 years, 1.75 ± 0.07 m, 76 ± 7 kg) and nine participants fitted with transfemoral socket-suspended prostheses arm (59 ± 9 years, 1.73 ± 0.07 m, 80 ± 16 kg). The intervention arm included nine participants fitted with transfemoral bone-anchored prostheses arm (51 ± 13 years, 1.78 ± 0.09 m, 87.3 ± 16.1 kg). INTERVENTION: Fitting of transfemoral bone-anchored prostheses. MAIN MEASURES: Comparisons were performed for two spatio-temporal, three spatial and nine temporal gait parameters. RESULTS: The cadence and speed of walking were 107 ± 6 steps/min and 1.23 ± 0.19 m/s for the able-bodied participants arm, 88 ± 7 steps/min and 0.87 ± 0.17 m/s for the socket-suspended prosthesis arm, and 96 ± 6 steps/min and 1.03 ± 0.17 m/s for bone-anchored prosthesis arm, respectively. Able-bodied participants and bone-anchored prosthesis arms were comparable in age, height, and body mass index as well as cadence and speed of walking, but the able-bodied participant arm showed a swing phase 31% shorter. Bone-anchored and socket-suspended prostheses arms were comparable for age, height, mass, and body mass index as well as cadence and speed of walking, but the bone-anchored prosthesis arm showed a step width and duration of double support in seconds 65% and 41% shorter, respectively. CONCLUSIONS: Bone-anchored and socket-suspended prostheses restored equally well the gait parameters at a self-selected speed. This benchmark data provides new insights into the walking ability of individuals using transfemoral bionics bone-anchored prostheses.


Assuntos
Amputados , Membros Artificiais , Prótese Ancorada no Osso , Humanos , Amputação Cirúrgica , Estudos Retrospectivos , Estudos Transversais , Marcha , Caminhada , Fenômenos Biomecânicos , Desenho de Prótese
11.
Neurosurg Focus ; 54(4): E3, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37004134

RESUMO

OBJECTIVE: Acute hydrocephalus is a frequent complication after aneurysmal subarachnoid hemorrhage (aSAH). Among patients needing CSF diversion, some cannot be weaned. Little is known about the comparative neurological, neuropsychological, and health-related quality-of-life (HRQOL) outcomes in patients with successful and unsuccessful CSF weaning. The authors aimed to assess outcomes of patients by comparing those with successful and unsuccessful CSF weaning; the latter was defined as occurring in patients with permanent CSF diversion at 3 months post-aSAH. METHODS: The authors included prospectively recruited alert (i.e., Glasgow Coma Scale score 13-15) patients with aSAH in this retrospective study from six Swiss neurovascular centers. Patients underwent serial neurological (National Institutes of Health Stroke Scale), neuropsychological (Montreal Cognitive Assessment), disability (modified Rankin Scale), and HRQOL (EuroQol-5D) examinations at < 72 hours, 14-28 days, and 3 months post-aSAH. RESULTS: Of 126 included patients, 54 (42.9%) developed acute hydrocephalus needing CSF diversion, of whom 37 (68.5%) could be successfully weaned and 17 (31.5%) required permanent CSF diversion. Patients with unsuccessful weaning were older (64.5 vs 50.8 years, p = 0.003) and had a higher rate of intraventricular hemorrhage (52.9% vs 24.3%, p = 0.04). Patients who succeed in restoration of physiological CSF dynamics improve on average by 2 points on the Montreal Cognitive Assessment between 48-72 hours and 14-28 days, whereas those in whom weaning fails worsen by 4 points (adjusted coefficient 6.80, 95% CI 1.57-12.04, p = 0.01). They show better neuropsychological recovery between 48-72 hours and 3 months, compared to patients in whom weaning fails (adjusted coefficient 7.60, 95% CI 3.09-12.11, p = 0.02). Patients who receive permanent CSF diversion (ventriculoperitoneal shunt) show significant neuropsychological improvement thereafter, catching up the delay in neuropsychological improvement between 14-28 days and 3 months post-aSAH. Neurological, disability, and HRQOL outcomes at 3 months were similar. CONCLUSIONS: These results show a temporary but clinically meaningful cognitive benefit in the first weeks after aSAH in successfully weaned patients. The resolution of this difference over time may be due to the positive effects of permanent CSF diversion and underlines its importance. Patients who do not show progressive neuropsychological improvement after weaning should be considered for repeat CT imaging to rule out chronic (untreated) hydrocephalus.


Assuntos
Hidrocefalia , Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/cirurgia , Estudos Retrospectivos , Suíça , Desmame , Hidrocefalia/cirurgia , Hidrocefalia/complicações
12.
Molecules ; 28(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37513446

RESUMO

Species of the genus Kalanchoe have a long history of therapeutic use in ethnomedicine linked to their remarkable healing properties. Several species have chemical and anatomical similarities, often leading to confusion when they are used in folk medicine. This review aims to provide an overview and discussion of the reported traditional uses, botanical aspects, chemical constituents, and pharmacological potential of the Kalanchoe species. Published scientific materials were collected from the PubMed and SciFinder databases without restriction regarding the year of publication through April 2023. Ethnopharmacological knowledge suggests that these species have been used to treat infections, inflammation, injuries, and other disorders. Typically, all parts of the plant are used for medicinal purposes either as crude extract or juice. Botanical evaluation can clarify species differentiation and can enable correct identification and validation of the scientific data. Flavonoids are the most common classes of secondary metabolites identified from Kalanchoe species and can be correlated with some biological studies (antioxidant, anti-inflammatory, and antimicrobial potential). This review summarizes several topics related to the Kalanchoe genus, supporting future studies regarding other unexplored research areas. The need to conduct further studies to confirm the popular uses and biological activities of bioactive compounds is also highlighted.


Assuntos
Crassulaceae , Kalanchoe , Plantas Medicinais , Fitoterapia , Compostos Fitoquímicos/química , Etnofarmacologia , Extratos Vegetais/química
13.
Surg Radiol Anat ; 45(4): 375-387, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36786934

RESUMO

BACKGROUND AND PURPOSE: Internal carotid artery (ICA) agenesis is a rare anatomical variant that can involve different segments of the ICA. Although many authors proposed their own classifications of this variant basing on different criteria, none of these allows to include all the cases described in the literature. The aim of the authors is to propose a new classification that allows to include all cases of ICA agenesis described until now. MATERIALS AND METHODS: The study is based on the review of all the cases of ICA agenesis described in the literature and of the classifications already proposed. After the analysis of these cases, we looked for the limits of each classification to elaborate a new more complete one. RESULTS: We found 228 cases of ICA agenesis. Among them 40 were not includible in the existing classifications. For this reason, we proposed a new classification based on the type of flow compensation and on the embryological events that determine the different variants. The flow is compensated in Type I by the Circle of Willis; in Type II by the non-regression of an embryonic artery; in Type III by the presence of an arterio-arterial anastomosis and in Type IV by external-internal carotid arteries anastomoses. CONCLUSION: After the literature review, we proposed a new comprehensive classification based on the detailed analysis of arterial embryology. Even if all the embryological details that determine this complex variant are not completely understood yet, this classification allows to include all the cases described in literature.


Assuntos
Angiografia , Artéria Carótida Interna , Humanos , Artéria Carótida Externa , Artéria Carótida Interna/anormalidades , Artérias Cerebrais , Circulação Colateral
15.
J Nat Prod ; 85(6): 1449-1458, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35622967

RESUMO

Aureobasidin A (abA) is a natural depsipeptide that inhibits inositol phosphorylceramide (IPC) synthases with significant broad-spectrum antifungal activity. abA is known to have two distinct conformations in solution corresponding to trans- and cis-proline (Pro) amide bond rotamers. While the trans-Pro conformation has been studied extensively, cis-Pro conformers have remained elusive. Conformational properties of cyclic peptides are known to strongly affect both potency and cell permeability, making a comprehensive characterization of abA conformation highly desirable. Here, we report a high-resolution 3D structure of the cis-Pro conformer of aureobasidin A elucidated for the first time using a recently developed NMR-driven computational approach. This approach utilizes ForceGen's advanced conformational sampling of cyclic peptides augmented by sparse distance and torsion angle constraints derived from NMR data. The obtained 3D conformational structure of cis-Pro abA has been validated using anisotropic residual dipolar coupling measurements. Support for the biological relevance of both the cis-Pro and trans-Pro abA configurations was obtained through molecular similarity experiments, which showed a significant 3D similarity between NMR-restrained abA conformational ensembles and another IPC synthase inhibitor, pleofungin A. Such ligand-based comparisons can further our understanding of the important steric and electrostatic characteristics of abA and can be utilized in the design of future therapeutics.


Assuntos
Depsipeptídeos , Prolina , Depsipeptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Prolina/química , Conformação Proteica
16.
J Clin Apher ; 37(1): 91-99, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34874570

RESUMO

BACKGROUND: Rheopheresis is a double-filtration plasmapheresis that removes high-molecular-weight molecules from the plasma and thereby lowers blood viscosity. This treatment has been proposed in hemodialysis (HD) patients for chronic limb-threatening ischemia (CLTI), but very few studies have evaluated the usefulness of this technique. PRINCIPAL OBJECTIVE: To assess 1-year amputation-free survival (AFS) of HD patients suffering from CLTI treated by rheopheresis. MATERIAL AND METHOD: We conducted a retrospective study of 28 consecutive HD patients treated by rheopheresis in three French dialysis centers between 1 February 2017 and 30 April 2019 in two indications resulting from CLTI, namely chronic ulceration or recent minor amputation with delayed healing. RESULTS: One-year AFS rate reached 53.6 (-19.8; +16.3)%. One-year overall survival rate reached 67.9 (-20.5; +13.1)%. Main causes of death were infections and related to palliative care implying reduction or withdrawal of regular dialysis treatment. Hypotension episodes were the main rheopheresis adverse events with a prevalence rate of 13.5%. Rheopheresis sessions significantly reduced fibrinogen, C-reactive protein, α2-macroglobulin, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, IgM, and estimated plasma viscosity (P < .0001). CONCLUSION: Rheopheresis may improve clinical outcomes of CLTI in HD patients. The assessment of rheopheresis effectiveness needs to be confirmed by a multicenter randomized controlled trial, such as the ongoing project in France (RHEO-PAD, NCT: 03975946).


Assuntos
Doença Arterial Periférica/terapia , Plasmaferese/métodos , Diálise Renal , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/cirurgia , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores de Tempo
17.
Pediatr Surg Int ; 38(2): 331-335, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34741643

RESUMO

PURPOSE: Congenital oesophageal stenosis (COS) is characterised by an intrinsic oesophageal narrowing that is present, but not necessarily symptomatic at birth. Small studies report an association of COS with oesophageal atresia (OA) in up to 14% of OA cases. Although OA is usually appreciated shortly after birth, the diagnosis of a concomitant COS is frequently delayed. This risk may be increased with the current movement away from routine postoperative upper gastrointestinal (GI) contrast study following OA repair. We performed a systematic review of the literature to assess the timing of diagnosis of COS in patients with COS and OA and how this impacted on patient outcomes. METHODS: A systematic review in accordance with PRISMA guidelines was undertaken. Only patients with OA associated with COS were included. Delayed diagnosis was defined as presentation > 1 month of age. RESULTS: 14 full-text studies with a total of 131 patients were included. Diagnosis of COS was delayed in 62/131 (47%) patients. These children presented with symptoms of dysphagia and aspiration at a median age of 13.5 months (IQR 7-30 months). In total, 18/131 patients were identified at the initial operation, due to difficulty passing a tube distally into the stomach. The data on timing of contrast studies were provided in 60/131 (46%) patients. A routine postoperative contrast study was performed in 39/60 (65%) of these, of which COS was identified immediately in 28/39 (72%). A diagnosis of COS could also be made on retrospective review of the early contrast study in a further 6/39 patients, giving an overall sensitivity of 87%. CONCLUSION: The association of COS and OA may be underrecognised and diagnosis delayed if routine contrast study is not performed. Contrast studies, performed in the neonatal period are effective at detecting a concomitant COS (sensitivity > 87%). This review supports routine early contrast study after OA repair with specific consideration of the presence of COS.


Assuntos
Transtornos de Deglutição , Atresia Esofágica , Estenose Esofágica , Fístula Traqueoesofágica , Criança , Pré-Escolar , Atresia Esofágica/complicações , Atresia Esofágica/cirurgia , Estenose Esofágica/etiologia , Estenose Esofágica/cirurgia , Humanos , Lactente , Recém-Nascido , Estudos Retrospectivos
18.
Pediatr Surg Int ; 38(4): 569-572, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35175402

RESUMO

PURPOSE: Children requiring long-term ventilation (LTV) via tracheostomy often require enteral tube feeding. We sought to investigate what proportion of these children underwent gastrostomy insertion to inform decision making at time of tracheostomy formation. METHODS: A retrospective review of all children commenced on LTV via a tracheostomy at Royal Manchester Children's Hospital over a 9-year period (2012-2020). Data are presented as median [IQR]. RESULTS: Forty-one LTV patients had tracheostomy insertion with an average age of 167 days [101-604]. Reasons for tracheostomy insertion were upper airway obstruction (18), central neurological condition (7), neuromuscular condition (12) and lower respiratory tract disease (4). Twenty-two patients were born preterm and chronic lung disease of prematurity was a contributory factor in their requirement for LTV. Eight children had gastrostomies inserted prior to tracheostomy formation. A further 22 children had a gastrostomy inserted at an average of 139 days [99-227] following tracheostomy. Four children remained on nasogastric feed and the rest were fed orally. Seventy-three percentage of LTV children with tracheostomy were gastrostomy fed. Neither indication for LTV nor prematurity predicted whether a child was gastrostomy fed. CONCLUSION: The large majority of children requiring LTV are tube fed and gastrostomy insertion should be considered at time of formation of tracheostomy.


Assuntos
Gastrostomia , Traqueostomia , Criança , Nutrição Enteral , Humanos , Recém-Nascido , Respiração Artificial , Estudos Retrospectivos
19.
Molecules ; 27(19)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36234686

RESUMO

Three series of our lead CLK1 inhibitor DB18 have been designed, synthetized and tested against CLKs and DYRK1A kinases. Their cytotoxicity was subsequently measured on seven representative cancer cell lines. Guided by docking experiments, we focused on the less constrained part of the scaffold, and showed that drastically different substituents can be tolerated here. This work ended with the discovery of another promising derivative 12g, with IC50 = 0.004 µM in the inhibition of HsCLK1 and IC50 = 3.94 µM for the inhibition of HsDYRK1A. The SAR results are discussed in the light of extensive molecular modeling analyses. Finally, a kinome scan (463 human kinases) confirmed the outstanding selectivity of our lead compound DB18, suggesting that this scaffold is of prominent interest for selective CLK inhibitors. Altogether, these results pave the way for the development of inhibitors with novel selectivities in this family of kinases.


Assuntos
Inibidores de Proteínas Quinases , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade
20.
Surg Radiol Anat ; 44(5): 737-748, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35357524

RESUMO

The anterior cerebral artery (ACA) and the anterior communicating artery (AComA) are important arteries of the telencephalon and are prominent location for cerebral aneurysms. Their embryological development is closely linked, and explains the possible variants seen in adults. In this paper, we present details related to the development of these two arteries, focusing on some variants such as the infra-optic course of the ACA, the unpaired ACA, and the persistent primitive olfactory artery.


Assuntos
Artéria Cerebral Anterior , Aneurisma Intracraniano , Adulto , Angiografia Cerebral , Círculo Arterial do Cérebro , Humanos
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