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1.
Nucleic Acids Res ; 52(12): 6964-6976, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38142462

RESUMEN

BRCA2 tumor suppressor protein ensures genome integrity by mediating DNA repair via homologous recombination (HR). This function is executed in part by its canonical DNA binding domain located at the C-terminus (BRCA2CTD), the only folded domain of the protein. Most germline pathogenic missense variants are located in this highly conserved region which binds to single-stranded DNA (ssDNA) and to the acidic protein DSS1. These interactions are essential for the HR function of BRCA2. Here, we report that the variant R2645G, identified in breast cancer and located at the DSS1 interface, unexpectedly increases the ssDNA binding activity of BRCA2CTDin vitro. Human cells expressing this variant display a hyper-recombination phenotype, chromosomal instability in the form of chromatid gaps when exposed to DNA damage, and increased PARP inhibitor sensitivity. In mouse embryonic stem cells (mES), this variant alters viability and confers sensitivity to cisplatin and Mitomycin C. These results suggest that BRCA2 interaction with ssDNA needs to be tightly regulated to limit HR and prevent chromosomal instability and we propose that this control mechanism involves DSS1. Given that several missense variants located within this region have been identified in breast cancer patients, these findings might have clinical implications for carriers.


Asunto(s)
Proteína BRCA2 , ADN de Cadena Simple , Unión Proteica , Humanos , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Animales , Ratones , ADN de Cadena Simple/metabolismo , ADN de Cadena Simple/genética , Inestabilidad Cromosómica , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Cisplatino/farmacología , Daño del ADN , Mutación Missense , Femenino , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Células Madre Embrionarias de Ratones/metabolismo , Línea Celular Tumoral , Mitomicina/farmacología , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Complejo de la Endopetidasa Proteasomal
2.
EMBO J ; 40(7): e106018, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33634895

RESUMEN

The BRCA2 tumor suppressor is a DNA double-strand break (DSB) repair factor essential for maintaining genome integrity. BRCA2-deficient cells spontaneously accumulate DNA-RNA hybrids, a known source of genome instability. However, the specific role of BRCA2 on these structures remains poorly understood. Here we identified the DEAD-box RNA helicase DDX5 as a BRCA2-interacting protein. DDX5 associates with DNA-RNA hybrids that form in the vicinity of DSBs, and this association is enhanced by BRCA2. Notably, BRCA2 stimulates the DNA-RNA hybrid-unwinding activity of DDX5 helicase. An impaired BRCA2-DDX5 interaction, as observed in cells expressing the breast cancer variant BRCA2-T207A, reduces the association of DDX5 with DNA-RNA hybrids, decreases the number of RPA foci, and alters the kinetics of appearance of RAD51 foci upon irradiation. Our findings are consistent with DNA-RNA hybrids constituting an impediment for the repair of DSBs by homologous recombination and reveal BRCA2 and DDX5 as active players in their removal.


Asunto(s)
Proteína BRCA2/metabolismo , ARN Helicasas DEAD-box/metabolismo , Reparación del ADN por Recombinación , Proteína BRCA2/genética , Línea Celular Tumoral , ARN Helicasas DEAD-box/genética , Roturas del ADN de Doble Cadena , Células HEK293 , Humanos , Ácidos Nucleicos Heterodúplex , Unión Proteica
3.
Nucleic Acids Res ; 51(7): 3420-3435, 2023 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-36864742

RESUMEN

Obg is a widely conserved and essential GTPase in bacteria, which plays a central role in a large range of important cellular processes, such as ribosome biogenesis, DNA replication, cell division and bacterial persistence. Nevertheless, the exact function of Obg in these processes and the interactions it makes within the associated pathways remain largely unknown. Here, we identify the DNA-binding TrpD2 protein YbiB as an interactor of the Escherichia coli Obg (ObgE). We show that both proteins interact with high affinity in a peculiar biphasic fashion, and pinpoint the intrinsically disordered and highly negatively charged C-terminal domain of ObgE as a main driver for this interaction. Molecular docking and X-ray crystallography, together with site-directed mutagenesis, are used to map the binding site of this ObgE C-terminal domain within a highly positively charged groove on the surface of the YbiB homodimer. Correspondingly, ObgE efficiently inhibits the binding of DNA to YbiB, indicating that ObgE competes with DNA for binding in the positive clefts of YbiB. This study thus forms an important step for the further elucidation of the interactome and cellular role of the essential bacterial protein Obg.


Asunto(s)
Proteínas de Escherichia coli , Proteínas de Unión al GTP Monoméricas , Proteínas de Escherichia coli/metabolismo , Proteínas de Unión al GTP Monoméricas/genética , Simulación del Acoplamiento Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Bacterianas/metabolismo , ADN/metabolismo , Proteínas de Unión al ADN/metabolismo
4.
Small ; 19(20): e2206795, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36807731

RESUMEN

Peptide-based hydrogels are promising biocompatible materials for wound healing, drug delivery, and tissue engineering applications. The physical properties of these nanostructured materials depend strongly on the morphology of the gel network. However, the self-assembly mechanism of the peptides that leads to a distinct network morphology is still a subject of ongoing debate, since complete assembly pathways have not yet been resolved. To unravel the dynamics of the hierarchical self-assembly process of the model ß-sheet forming peptide KFE8 (Ac-FKFEFKFE-NH2 ), high-speed atomic force microscopy (HS-AFM) in liquid is used. It is demonstrated that a fast-growing network, based on small fibrillar aggregates, is formed at a solid-liquid interface, while in bulk solution, a distinct, more prolonged nanotube network emerges from intermediate helical ribbons. Moreover, the transformation between these morphologies has been visualized. It is expected that this new in situ and in real-time methodology will set the path for the in-depth unravelling of the dynamics of other peptide-based self-assembled soft materials, as well as gaining advanced insights into the formation of fibers involved in protein misfolding diseases.


Asunto(s)
Nanoestructuras , Péptidos , Conformación Proteica en Lámina beta , Péptidos/química , Nanoestructuras/química , Sistemas de Liberación de Medicamentos , Microscopía de Fuerza Atómica
5.
HIV Med ; 24(6): 754-759, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36883615

RESUMEN

OBJECTIVES: Pre-travel counselling has demonstrated its efficacy in decreasing travel-related health complications. The current profile of people living with HIV (PLWH) in Europe [increasing age, visiting friends and relatives (VFR)] makes pre-travel counselling crucial. We aimed to survey the self-reported travel patterns and advice-seeking behaviour among PLWH followed up at the HIV Reference Centre (HRC) of Saint-Pierre Hospital, Brussels. METHODS: A survey was conducted in all PLWH presenting at the HRC from February to June 2021. The survey covered demographic elements, travel and pre-travel consultation habits over the last 10 years, or since the diagnosis of HIV if it was made less than 10 years earlier. RESULTS: The survey was completed by 1024 PLWH (35% women, median age 49 years, the majority being virologically controlled). A substantial number of PLWH were involved in VFR travel in low-resource countries and 65% sought pre-travel advice before travelling: if not, it was because they did not know it was necessary (91%). CONCLUSION: Travel is common among PLWH. Raising awareness of the importance of pre-travel counselling should be a routine part of every healthcare encounter and especially during regular contact with HIV physicians.


Asunto(s)
Infecciones por VIH , Viaje , Humanos , Femenino , Persona de Mediana Edad , Masculino , Enfermedad Relacionada con los Viajes , Bélgica/epidemiología , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Europa (Continente)
6.
HIV Med ; 24(12): 1190-1197, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37772682

RESUMEN

OBJECTIVE: Review the evidence on the incidence and impact of herpes zoster among people living with HIV and the potential impact of recombinant zoster vaccine for people aging with HIV. METHODS: Narrative review. RESULTS: Although antiretroviral therapy has substantially reduced the risk of herpes zoster among people living with HIV, they remain at an increased risk compared with the general population. Among people aging with HIV, aging per se is now the main risk factor for herpes zoster. Beyond pain, herpes zoster is also associated with a risk of sight-threatening complications in case of trigeminal involvement, disseminated diseases and stroke. Post-herpetic neuralgia is also a potential threat to the quality of life of people aging with HIV. The recombinant zoster vaccine has demonstrated high and sustained efficacy in the prevention of herpes zoster, post-herpetic neuralgia, and other herpes zoster complications in the general population. Immunogenicity data among people living with HIV with high CD4+ T-cell count and controlled viral load are comparable to those among the general population. Real-life effectiveness data indicate high vaccine efficacy among immunocompromised patients other than people living with HIV. High vaccine price, vaccine hesitancy, and limited disease and vaccine awareness represent potential hurdles for high vaccine uptake among people aging with HIV in Europe. CONCLUSIONS: Herpes zoster, and its complications, is a vaccine-preventable disease of aging people. Given its impact on quality of life, herpes zoster prevention using recombinant zoster vaccine is a safe strategy to be considered in every person aging with HIV.


Asunto(s)
Infecciones por VIH , Vacuna contra el Herpes Zóster , Herpes Zóster , Neuralgia Posherpética , Humanos , Neuralgia Posherpética/prevención & control , Neuralgia Posherpética/epidemiología , Calidad de Vida , Infecciones por VIH/complicaciones , Herpes Zóster/prevención & control , Herpes Zóster/epidemiología , Herpesvirus Humano 3 , Envejecimiento
7.
Eur Radiol ; 33(2): 1162-1173, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35980435

RESUMEN

OBJECTIVES: Synovial sarcomas (SS) of the extremities are rare soft tissue sarcomas that are more common in young adults. We deciphered the imaging phenotype of SS with the aim to determine if imaging could provide an incremental value to currently known prognostic factors (PF)-age and histological grade-to predict long-term overall survival (OS). METHODS: This retrospective multicenter study included consecutive pediatric and adult patients with synovial sarcomas of the extremities from December 2002 to August 2020. Inclusion criteria were (i) a follow-up greater than 5 years and (ii) available pre-therapeutic MRI. A subset analysis included MRI and CT-scan. Clinical, pathological, and imaging variables were collected in all patients. The primary endpoint was to evaluate the association of these variables with OS using univariate and multivariate Cox regressions. RESULTS: Out of 428 patients screened for eligibility, 98 patients (mean age: 37.1 ± 15.2 years) were included (MRI: n = 98/98, CT scan: n = 34/98; 35%). The median OS was 75.25 months (IQR = 55.50-109.12) and thirty-six patients (n = 36/98;37%) died during follow-up. The recurrence rate was 12.2% (n =12/98). SS lesions were mostly grade 2 (57/98; 58%). On MRI, SS had a mean long-axis diameter of 67.5 ± 38.3 mm. On CT scan, 44% (15/34) were calcified. Grade (hazard ratio [HR] = 2.71; 95%CI = 1.30-5.66; p = 0.008), size of the lesions evaluated on MRI (HR = 1.02; 95% CI = 1.01-1.03; p < 0.001), and calcifications on CT scan (HR = 0.10; 95% CI = 0.02-0.50; p = 0.005) were independent PF of OS. CONCLUSIONS: This study demonstrated that imaging biomarkers can be used to predict long-term outcome in patients with SS. Strikingly, the presence of calcifications on CT scan is associated with favorable outcome and provides an incremental value over existing PF such as age, grade, and size. KEY POINTS: • Beyond its diagnostic value, MRI is a pre-operative prognostic tool in synovial sarcomas of the extremities since the size of the lesion is an important prognostic factor. • Calcifications on CT scans are independently and significantly associated with prolonged overall survival.


Asunto(s)
Sarcoma Sinovial , Sarcoma , Humanos , Pronóstico , Sarcoma Sinovial/diagnóstico por imagen , Sarcoma/patología , Extremidades/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Estudios Retrospectivos
8.
Bioorg Chem ; 138: 106612, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37210827

RESUMEN

Pannexin1 channels facilitate paracrine communication and are involved in a broad spectrum of diseases. Attempts to find appropriate pannexin1 channel inhibitors that showcase target-selective properties and in vivo applicability remain nonetheless scarce. However, a promising lead candidate, the ten amino acid long peptide mimetic 10Panx1 (H-Trp1-Arg2-Gln3-Ala4-Ala5-Phe6-Val7-Asp8-Ser9-Tyr10-OH), has shown potential as a pannexin1 channel inhibitor in both in vitro and in vivo studies. Nonetheless, structural optimization is critical for clinical use. One of the main hurdles to overcome along the optimization process consists of subduing the low biological stability (10Panx1 t1/2 = 2.27 ± 0.11 min). To tackle this issue, identification of important structural features within the decapeptide structure is warranted. For this reason, a structure-activity relationship study was performed to proteolytically stabilize the sequence. Through an Alanine scan, this study demonstrated that the side chains of Gln3 and Asp8 are crucial for 10Panx1's channel inhibitory capacity. Guided by plasma stability experiments, scissile amide bonds were identified and stabilized, while extracellular adenosine triphosphate release experiments, indicative of pannexin1 channel functionality, allowed to enhance the in vitro inhibitory capacity of 10Panx1.


Asunto(s)
Fragmentos de Péptidos , Péptidos , Secuencia de Aminoácidos , Péptidos/farmacología , Aminoácidos , Alanina
9.
Angew Chem Int Ed Engl ; 62(24): e202219095, 2023 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-37067463

RESUMEN

RAS proteins control various intracellular signaling networks. Mutations at specific locations were shown to stabilize their active guanosine triphosphate (GTP)-bound state, which is associated with the development of multiple cancers. An attractive approach to modulate RAS signaling is through its regulatory guanine nucleotide exchange factor (GEF) son of sevenless 1 (SOS1). With the recent discovery of Nanobody14 (Nb14), which potently enhances SOS1-catalyzed nucleotide exchange on RAS, we explored the feasibility of developing peptide mimetics by structurally mimicking the complementarity-determining region 3 (CDR3). Guided by a biochemical GEF assay and X-ray co-crystal structures, successive rounds of optimization and gradual conformational rigidification led to CDR3 mimetics showing half of the maximal activation potential of Nb14 with an EC50 value of 29 µM. Altogether, this study demonstrated that peptides able to modulate a protein-protein interaction can be obtained by structural mimicry of a Nb paratope.


Asunto(s)
Núcleo Familiar , Nucleótidos , Transducción de Señal , Factores de Intercambio de Guanina Nucleótido/metabolismo , Catálisis
10.
Exp Cell Res ; 405(1): 112656, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34033760

RESUMEN

DYRK1A, one of the dual-specificity tyrosine phosphorylation-regulated kinases (DYRKs), plays an important role in various biological processes by regulating downstream targets via kinase-dependent and independent mechanisms. Here, we report a novel role of DYRK1A in maintaining tumor growth and stemness of oral/oropharyngeal squamous cell carcinoma (OSCC) cells. Deletion of DYRK1A from OSCC cells abrogated their in vivo tumorigenicity and self-renewal capacity, the key features of cancer stem-like cells (CSCs; also referred to as tumor-initiating cells). The DYRK1A deletion also induced the suppression of CSC populations and properties, such as migration ability and chemoresistance. Conversely, ectopic expression of DYRK1A in OSCC cells augmented their CSC phenotype. Among five DYRK members (DYRK1A, 1B, 2, 3, and 4), DYRK1A is the most dominantly expressed kinase, and its expression is upregulated in OSCC compared to normal oral epithelial cells. More importantly, DYRK1A was highly enriched in various CSC-enriched OSCC populations compared to their corresponding non-CSC populations, indicating its pivotal role in cancer progression and stemness. Further, our study revealed that fibroblast growth factor 2 (FGF2) is a key regulator in the DYRK1A-mediated CSC regulation. Functional studies demonstrated that the loss of DYRK1A inhibits CSC phenotype via reduction of FGF2. Overexpression of DYRK1A promotes CSC phenotype via upregulation of FGF2. Our study delineates a novel mechanism of cancer stemness regulation by DYRK1A-FGF2 axis in OSCC. Thus, inhibition of DYRK1A would lead to a potential novel therapeutic option for targeting CSCs in OSCC.


Asunto(s)
Carcinogénesis/patología , Carcinoma de Células Escamosas/patología , Regulación Neoplásica de la Expresión Génica , Neoplasias de la Boca/patología , Células Madre Neoplásicas/patología , Neoplasias Orofaríngeas/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Animales , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinogénesis/genética , Carcinogénesis/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Proliferación Celular , Humanos , Ratones , Ratones Desnudos , Neoplasias de la Boca/genética , Neoplasias de la Boca/metabolismo , Células Madre Neoplásicas/metabolismo , Neoplasias Orofaríngeas/genética , Neoplasias Orofaríngeas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Tirosina Quinasas/genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto , Quinasas DyrK
11.
Nature ; 530(7591): 495-8, 2016 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-26886796

RESUMEN

The orientation of cell division along the long axis of the interphase cell--the century-old Hertwig's rule--has profound roles in tissue proliferation, morphogenesis, architecture and mechanics. In epithelial tissues, the shape of the interphase cell is influenced by cell adhesion, mechanical stress, neighbour topology, and planar polarity pathways. At mitosis, epithelial cells usually adopt a rounded shape to ensure faithful chromosome segregation and to promote morphogenesis. The mechanisms underlying interphase cell shape sensing in tissues are therefore unknown. Here we show that in Drosophila epithelia, tricellular junctions (TCJs) localize force generators, pulling on astral microtubules and orienting cell division via the Dynein-associated protein Mud independently of the classical Pins/Gαi pathway. Moreover, as cells round up during mitosis, TCJs serve as spatial landmarks, encoding information about interphase cell shape anisotropy to orient division in the rounded mitotic cell. Finally, experimental and simulation data show that shape and mechanical strain sensing by the TCJs emerge from a general geometric property of TCJ distributions in epithelial tissues. Thus, in addition to their function as epithelial barrier structures, TCJs serve as polarity cues promoting geometry and mechanical sensing in epithelial tissues.


Asunto(s)
Forma de la Célula , Drosophila melanogaster/citología , Células Epiteliales/citología , Uniones Intercelulares , Interfase , Mitosis , Animales , Proteínas de Ciclo Celular , Polaridad Celular , Proteínas de Drosophila/metabolismo , Células Epiteliales/metabolismo , Epitelio/metabolismo , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Inhibidores de Disociación de Guanina Nucleótido/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Microtúbulos/metabolismo , Proteínas del Tejido Nervioso/metabolismo
12.
Am J Hum Biol ; 34(4): e23667, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34418235

RESUMEN

OBJECTIVE: To test the "vitamin D-folate hypothesis for the evolution of human skin pigmentation." METHODS: Total ozone mapping spectrometer (TOMS) satellite data were used to examine surface UV-irradiance in a large (n = 649) Australian cross-sectional study population. Genetic analysis was used to score vitamin D- and folate-related gene polymorphisms (n = 22), along with two pigmentation gene variants (IRF4-rs12203592/HERC2-rs12913832). Red cell folate and vitamin D3 were measured by immunoassay and HPLC, respectively. RESULTS: Ultraviolet radiation (UVR) and pigmentation genes interact to modify blood vitamin levels; Light skin IRF4-TT genotype has greatest folate loss while light skin HERC2-GG genotype has greatest vitamin D3 synthesis (reflected in both TOMS and seasonal data). UV-wavelength exhibits a dose-response relationship in folate loss within light skin IRF4-TT genotype (305 > 310 > 324 > 380 nm). Significant vitamin D3 photosynthesis only occurs within light skin HERC2-GG genotype, and is maximal at 305 nm. Three dietary antioxidants (vitamins C, E, and ß-carotene) interact with UVR and pigmentation genes preventing oxidative loss of labile reduced folate vitamers, with greatest benefit in light skin IRF4-TT subjects. The putative photosensitiser, riboflavin, did not sensitize red cell folate to UVR and actually afforded protection. Four genes (5xSNPs) influenced blood vitamin levels when stratified by pigmentation genotype; MTHFR-rs1801133/rs1801131, TS-rs34489327, CYP24A-rs17216707, and VDR-ApaI-rs7975232. Lightest IRF4-TT/darkest HERC2-AA genotype combination (greatest folate loss/lowest vitamin D3 synthesis) has 0% occurrence. The opposing, commonest (39%) compound genotype (darkest IRF4-CC/lightest HERC2-GG) permits least folate loss and greatest synthesis of vitamin D3 . CONCLUSION: New biophysical evidence supports the vitamin D-folate hypothesis for evolution of skin pigmentation.


Asunto(s)
Pigmentación de la Piel , Vitamina D , Australia , Estudios Transversales , Ácido Fólico , Genotipo , Humanos , Pigmentación de la Piel/genética , Rayos Ultravioleta/efectos adversos , Vitaminas
13.
Euro Surveill ; 27(9)2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35241214

RESUMEN

Although most invasive meningococcal disease (IMD) cases are sporadic without identified transmission links, outbreaks can occur. We report three cases caused by meningococcus B (MenB) at a Belgian nursery school over 9 months. The first two cases of IMD occurred in spring and summer 2018 in healthy children (aged 3-5 years) attending the same classroom. Chemoprophylaxis was given to close contacts of both cases following regional guidelines. The third case, a healthy child of similar age in the same class as a sibling of one case, developed disease in late 2018. Microbiological analyses revealed MenB with identical finetype clonal complex 269 for Case 1 and 3 (unavailable for Case 2). Antimicrobial susceptibility testing revealed no antibiotic resistance. Following Case 3, after multidisciplinary discussion, chemoprophylaxis and 4CMenB (Bexsero) vaccination were offered to close contacts. In the 12-month follow-up of Case 3, no additional cases were reported by the school. IMD outbreaks are difficult to manage and generate public anxiety, particularly in the case of an ongoing cluster, despite contact tracing and management. This outbreak resulted in the addition of MenB vaccination to close contacts in Wallonian regional guidelines, highlighting the potential need and added value of vaccination in outbreak management.


Asunto(s)
Infecciones Meningocócicas , Vacunas Meningococicas , Neisseria meningitidis Serogrupo B , Bélgica/epidemiología , Niño , Preescolar , Brotes de Enfermedades , Humanos , Infecciones Meningocócicas/diagnóstico , Infecciones Meningocócicas/tratamiento farmacológico , Infecciones Meningocócicas/epidemiología , Instituciones Académicas , Escuelas de Párvulos , Serogrupo
14.
BMC Med Educ ; 22(1): 678, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36104703

RESUMEN

INTRODUCTION: The transition from medical student to surgical resident is not a simple one. The aim of this study was to report the experience of a university hospital in the organization of the induction course for future surgical residents and the contribution of a video support in the learning of the suture. MATERIAL AND METHOD: We were able to study two consecutive years of students (October 2020 and 2021). Concerning the practical and technical workshops (learning suture) we carried out a comparative study between two groups of students. A group that had video support for learning suture (video group) and a group without video (control group). The evaluation of the suture was performed in a blinded manner by two supervising surgeons. The other practical workshop was drain fixation; the students did not have a video for this workshop. A comparative study was also performed for the drain fixation workshop between the two groups (video group and control group). A program of theoretical courses was also set up. This program is established according to the different future functions of the residents by integrating medico-legal notions and teamwork. Satisfaction questionnaires were given to the students and the answers were given two months after taking up their duties in the hospital (6 questions with Likert scale and 4 free questions). RESULTS: The cohort consisted of 58 students (29 each in 2020 and 29 in 2021). Comparative analyses of the evaluation of the suture workshops showed better performance in the video group compared with the group without video. The comparison of these two groups did not show significant differences in the drain fixation workshop. The theoretical teaching was broken down according to the students' future tasks and each speaker was a specialist in his or her field of expertise. The results of the questionnaires showed a desire on the part of the students to increase the time spent on practical workshops and theoretical forensic teaching. CONCLUSION: We were able to show through these two years of a program that we were able to offer a surgical resident preparation course. In addition, we have highlighted the contribution of a video support in the learning curve of the suture.


Asunto(s)
Internado y Residencia , Estudiantes de Medicina , Evaluación Educacional , Retroalimentación , Femenino , Hospitales Universitarios , Humanos , Masculino
15.
Molecules ; 27(24)2022 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-36557917

RESUMEN

There is still an unmet clinical need to develop new pharmaceuticals for effective and safe pain management. Current pharmacotherapy offers unsatisfactory solutions due to serious side effects related to the chronic use of opioid drugs. Prescription opioids produce analgesia through activation of the mu-opioid receptor (MOR) and are major contributors to the current opioid crisis. Multifunctional ligands possessing activity at more than one receptor represent a prominent therapeutic approach for the treatment of pain with fewer adverse effects. We recently reported on the design of a bifunctional MOR agonist/neuropeptide FF receptor (NPFFR) antagonist peptididomimetic, KGFF09 (H-Dmt-DArg-Aba-ßAla-Bpa-Phe-NH2), and its antinociceptive effects after subcutaneous (s.c.) administration in acute and persistent pain in mice with reduced propensity for unwanted side effects. In this study, we further investigated the antinociceptive properties of KGFF09 in a mouse model of visceral pain after s.c. administration and the potential for opioid-related liabilities of rewarding and sedation/locomotor dysfunction following chronic treatment. KGFF09 produced a significant dose-dependent inhibition of the writhing behavior in the acetic acid-induced writhing assay with increased potency when compared to morphine. We also demonstrated the absence of harmful effects caused by typical MOR agonists, i.e., rewarding effects (conditioned-place preference test) and sedation/locomotor impairment (open-field test), at a dose shown to be highly effective in inhibiting pain behavior. Consequently, KGFF09 displayed a favorable benefit/side effect ratio regarding these opioid-related side effects compared to conventional opioid analgesics, such as morphine, underlining the development of dual MOR agonists/NPFFR antagonists as improved treatments for various pain conditions.


Asunto(s)
Peptidomiméticos , Dolor Visceral , Ratones , Animales , Analgésicos Opioides , Peptidomiméticos/farmacología , Dolor Visceral/tratamiento farmacológico , Dolor Visceral/inducido químicamente , Morfina/farmacología , Receptores Opioides mu/metabolismo , Proteínas de Unión al GTP
16.
Malar J ; 20(1): 214, 2021 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-33964945

RESUMEN

BACKGROUND: European travellers to endemic countries are at risk of malaria and may be affected by a different range of co-morbidities than natives of endemic regions. The safety profile, especially cardiac issues, of artenimol (previously dihydroartemisinin)-piperaquine (APQ) Eurartesim® during treatment of uncomplicated imported falciparum malaria is not adequately described due to the lack of longitudinal studies in this population. The present study was conducted to partially fill this gap. METHODS: Participants were recruited through Health Care Provider's safety registry in 15 centres across 6 European countries in the period 2013-2016. Adverse events (AE) were collected, with a special focus on cardiovascular safety by including electrocardiogram QT intervals evaluated after correction with either Bazett's (QTcB) or Fridericia's (QTcF) methods, at baseline and after treatment. QTcB and/or QTcF prolongation were defined by a value > 450 ms for males and children and > 470 ms for females. RESULTS: Among 294 participants, 30.3% were women, 13.7% of Caucasian origin, 13.5% were current smoker, 13.6% current alcohol consumer and 42.2% declared at least one illness history. The mean (SD) age and body mass index were 39.8 years old (13.2) and 25.9 kg/m2 (4.7). Among them, 75 reported a total of 129 AE (27 serious), 46 being suspected to be related to APQ (11 serious) and mostly labelled as due to haematological, gastrointestinal, or infection. Women and Non-African participants had significantly (p < 0.05) more AEs. Among AEs, 21 were due to cardiotoxicity (7.1%), mostly QT prolongation, while 6 were due to neurotoxicity (2.0%), mostly dizziness. Using QTcF correction, QT prolongation was observed in 17/143 participants (11.9%), only 2 of them reporting QTcF > 500 ms (milliseconds) but no clinical symptoms. Using QTcB correction increases of > 60 ms were present in 9 participants (6.3%). A trend towards increased prolongation was observed in those over 65 years of age but only a few subjects were in this group. No new safety signal was reported. The overall efficacy rate was 255/257 (99.2%). CONCLUSIONS: APQ appears as an effective and well-tolerated drug for treatment of malaria in patients recruited in European countries. AEs and QT prolongation were in the range of those obtained in larger cohorts from endemic countries. Trial registration This study has been registered in EU Post-Authorization Studies Register as EUPAS6942.


Asunto(s)
Artemisininas/uso terapéutico , Enfermedades Transmisibles Importadas/prevención & control , Malaria Falciparum/prevención & control , Quinolinas/uso terapéutico , Adolescente , Adulto , Anciano , Bélgica , Niño , Preescolar , Combinación de Medicamentos , Femenino , Francia , Alemania , Humanos , Italia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Sistema de Registros , España , Reino Unido , Adulto Joven
17.
Molecules ; 26(17)2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34500841

RESUMEN

Opioid agonists are well-established analgesics, widely prescribed for acute but also chronic pain. However, their efficiency comes with the price of drastically impacting side effects that are inherently linked to their prolonged use. To answer these liabilities, designed multiple ligands (DMLs) offer a promising strategy by co-targeting opioid and non-opioid signaling pathways involved in nociception. Despite being intimately linked to the Substance P (SP)/neurokinin 1 (NK1) system, which is broadly examined for pain treatment, the neurokinin receptors NK2 and NK3 have so far been neglected in such DMLs. Herein, a series of newly designed opioid agonist-NK2 or -NK3 antagonists is reported. A selection of reported peptidic, pseudo-peptidic, and non-peptide neurokinin NK2 and NK3 ligands were covalently linked to the peptidic µ-opioid selective pharmacophore Dmt-DALDA (H-Dmt-d-Arg-Phe-Lys-NH2) and the dual µ/δ opioid agonist H-Dmt-d-Arg-Aba-ßAla-NH2 (KGOP01). Opioid binding assays unequivocally demonstrated that only hybrids SBL-OPNK-5, SBL-OPNK-7 and SBL-OPNK-9, bearing the KGOP01 scaffold, conserved nanomolar range µ-opioid receptor (MOR) affinity, and slightly reduced affinity for the δ-opioid receptor (DOR). Moreover, NK binding experiments proved that compounds SBL-OPNK-5, SBL-OPNK-7, and SBL-OPNK-9 exhibited (sub)nanomolar binding affinity for NK2 and NK3, opening promising opportunities for the design of next-generation opioid hybrids.


Asunto(s)
Analgésicos Opioides/química , Antagonistas del Receptor de Neuroquinina-1/química , Peptidomiméticos/química , Receptores de Neuroquinina-1/química , Receptores Opioides mu/química , Secuencia de Aminoácidos , Humanos , Ligandos , Oligopéptidos/química , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad , Sustancia P/química
18.
Angew Chem Int Ed Engl ; 60(18): 10247-10254, 2021 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-33596327

RESUMEN

G protein-coupled receptors (GPCRs) represent an important group of membrane proteins that play a central role in modern medicine. Unfortunately, conformational promiscuity hampers full therapeutic exploitation of GPCRs, since the largest population of the receptor will adopt a basal conformation, which subsequently challenges screens for agonist drug discovery programs. Herein, we describe a set of peptidomimetics able to mimic the ability of G proteins in stabilizing the active state of the ß2 adrenergic receptor (ß2 AR) and the dopamine 1 receptor (D1R). During fragment-based screening efforts, these (un)constrained peptide analogues of the α5 helix in Gs proteins, were able to identify agonism pre-imprinted fragments for the examined GPCRs, and as such, they behave as a generic tool, enabling an engagement in agonist earmarked discovery programs.


Asunto(s)
Descubrimiento de Drogas , Proteínas de Unión al GTP/agonistas , Peptidomiméticos/farmacología , Receptores Acoplados a Proteínas G/agonistas , Proteínas de Unión al GTP/metabolismo , Humanos , Modelos Moleculares , Peptidomiméticos/síntesis química , Peptidomiméticos/química , Receptores Acoplados a Proteínas G/metabolismo
19.
Emerg Infect Dis ; 26(7): 1562-1566, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32271701

RESUMEN

We report a case of Argentine hemorrhagic fever diagnosed in a woman in Belgium who traveled from a disease-endemic area. Patient management included supportive care and combination therapy with ribavirin and favipiravir. Of 137 potential contacts, including friends, relatives, and healthcare and laboratory workers, none showed development of clinical symptoms of this disease.


Asunto(s)
Virus Junin , Ribavirina , Amidas , Animales , Bélgica , Modelos Animales de Enfermedad , Femenino , Humanos , Pirazinas , Ribavirina/uso terapéutico
20.
Headache ; 60(10): 2583-2588, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32990351

RESUMEN

BACKGROUND: The typical sign of intracranial hypotension (IH) is postural headache. However, IH can be associated with a large diversity of clinical or radiological signs leading to difficult diagnosis especially in case of coma. The association of cerebral venous thrombosis (CVT) and subdural hemorrhage is rare but should suggest the diagnosis of IH. METHODS: Case report. CASE DESCRIPTION: We report here a case of comatose patient due to spontaneous IH complicated by CVT and subdural hemorrhage. The correct diagnosis was delayed due to many confounding factors. IH was suspected after subdural hemorrhage recurrence and confirmed by magnetic resonance imaging (MRI). After 2 epidural patches with colloid, favorable outcome was observed. DISCUSSION: The most common presentation of IH is postural orthostatic headaches. In the present case report, the major clinical signs were worsening of consciousness and coma, which are a rare presentation. Diagnosis of IH is based on the association of clinical history, evocative symptomatology, and cerebral imaging. CVT occurs in 1-2% of IH cases and the association between IH, CVT, and subdural hemorrhage is rare. MRI is probably the key imaging examination. In the present case, epidural patch was performed after confounding factors for coma had been treated. Benefit of anticoagulation had to be balanced in this case with potential hemorrhagic complications, especially within the brain. CONCLUSION: Association of CVT and subdural hemorrhage should lead to suspect IH. Brain imaging can help and find specific signs of IH.


Asunto(s)
Coma/diagnóstico , Hematoma Subdural/diagnóstico , Hipotensión Intracraneal/diagnóstico , Trombosis Intracraneal/diagnóstico , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
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