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1.
Small ; 20(21): e2306612, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38126683

RESUMO

Healing of large calvarial bone defects remains challenging. An RNA-guided Split dCas12a system is previously harnessed to activate long non-coding RNA H19 (lncRNA H19, referred to as H19 thereafter) in bone marrow-derived mesenchymal stem cells (BMSCs). H19 activation in BMSCs induces chondrogenic differentiation, switches bone healing pathways, and improves calvarial bone repair. Since adipose-derived stem cells (ASCs) can be harvested more easily in large quantity, here it is aimed to use ASCs as an alternative cell source. However, H19 activation alone using the Split dCas12a system in ASCs failed to elicit evident chondrogenesis. Therefore, split dCas12a activators are designed more to co-activate other chondroinductive transcription factors (Sox5, Sox6, and Sox9) to synergistically potentiate differentiation. It is found that co-activation of H19/Sox5/Sox6 in ASCs elicited more potent chondrogenic differentiation than activation of Sox5/Sox6/Sox9 or H19 alone. Co-activating H19/Sox5/Sox6 in ASCs significantly augmented in vitro cartilage formation and in vivo calvarial bone healing. These data altogether implicated the potentials of the Split dCas12a system to trigger multiplexed gene activation in ASCs for differentiation pathway reprogramming and tissue regeneration.


Assuntos
Diferenciação Celular , Condrogênese , RNA Longo não Codificante , Fatores de Transcrição SOXD , Crânio , Fatores de Transcrição SOXD/metabolismo , Fatores de Transcrição SOXD/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Animais , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Tecido Adiposo/citologia , Células-Tronco/metabolismo , Células-Tronco/citologia , Osteogênese/genética
2.
J Chem Phys ; 160(5)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38310477

RESUMO

The binding of the receptor binding domain (RBD) of the SARS-CoV-2 spike protein to the host cell receptor angiotensin-converting enzyme 2 (ACE2) is the first step in human viral infection. Therefore, understanding the mechanism of interaction between RBD and ACE2 at the molecular level is critical for the prevention of COVID-19, as more variants of concern, such as Omicron, appear. Recently, atomic force microscopy has been applied to characterize the free energy landscape of the RBD-ACE2 complex, including estimation of the distance between the transition state and the bound state, xu. Here, using a coarse-grained model and replica-exchange umbrella sampling, we studied the free energy landscape of both the wild type and Omicron subvariants BA.1 and XBB.1.5 interacting with ACE2. In agreement with experiment, we find that the wild type and Omicron subvariants have similar xu values, but Omicron binds ACE2 more strongly than the wild type, having a lower dissociation constant KD.


Assuntos
COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , Enzima de Conversão de Angiotensina 2 , Mutação , Ligação Proteica
3.
Chem Soc Rev ; 52(18): 6497-6553, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37650302

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the devastating global COVID-19 pandemic announced by WHO in March 2020. Through unprecedented scientific effort, several vaccines, drugs and antibodies have been developed, saving millions of lives, but the fight against COVID-19 continues as immune escape variants of concern such as Delta and Omicron emerge. To develop more effective treatments and to elucidate the side effects caused by vaccines and therapeutic agents, a deeper understanding of the molecular interactions of SARS-CoV-2 with them and human cells is required. With special interest in computational approaches, we will focus on the structure of SARS-CoV-2 and the interaction of its spike protein with human angiotensin-converting enzyme-2 (ACE2) as a prime entry point of the virus into host cells. In addition, other possible viral receptors will be considered. The fusion of viral and human membranes and the interaction of the spike protein with antibodies and nanobodies will be discussed, as well as the effect of SARS-CoV-2 on protein synthesis in host cells.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pandemias , Glicoproteína da Espícula de Coronavírus , Anticorpos
4.
BMC Cancer ; 23(1): 621, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37400806

RESUMO

BACKGROUND: Sensitive and reproducible detection of residual disease after treatment is a major challenge for patients with locally advanced head and neck cancer. Indeed, the current imaging techniques are not always reliable enough to determine the presence of residual disease. The aim of the NeckTAR trial is to assess the ability of circulating DNA (cDNA), both tumoral and viral, at three months post-treatment, to predict residual disease, at the time of the neck dissection, among patients with partial cervical lymph node response on PET-CT, after potentiated radiotherapy. METHODS: This will be an interventional, multicentre, single-arm, open-label, prospective study. A blood sample will be screened for cDNA before potentiated radiotherapy and after 3 months if adenomegaly persists on the CT scan 3 months after the end of treatment. Patients will be enrolled in 4 sites in France. Evaluable patients, i.e. those with presence of cDNA at inclusion, an indication for neck dissection, and a blood sample at M3, will be followed for 30 months. Thirty-two evaluable patients are expected to be recruited in the study. DISCUSSION: The decision to perform neck dissection in case of persistent cervical adenopathy after radio-chemotherapy for locally advanced head and neck cancer is not always straightforward. Although studies have shown that circulating tumour DNA is detectable in a large proportion of patients with head and neck cancer, enabling the monitoring of response, the current data is insufficient to allow routine use of this marker. Our study could lead to better identification of patients who do not have residual lymph node disease in order to avoid neck dissection and preserve their quality-of-life while maintaining their prospects of survival. TRIAL REGISTRATION: Clinicaltrials.gov: NCT05710679, registered on 02/02/2023, https://clinicaltrials.gov/ct2/show/ . Identifier with the French National Agency for the Safety of Medicines and Health Products (ANSM): N°ID RCB 2022-A01668-35, registered on July 15th, 2022.


Assuntos
Carcinoma de Células Escamosas , Ácidos Nucleicos Livres , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas/patologia , DNA Complementar , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/radioterapia , Estudos Multicêntricos como Assunto , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Prospectivos
5.
Bioorg Med Chem Lett ; 92: 129409, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37453616

RESUMO

Phosphodiesterase 5 (PDE5) is a cyclic guanosine monophosphate-degrading enzyme involved in numerous biological pathways. Inhibitors of PDE5 are important therapeutics for the treatment of neurodegenerative diseases, including Alzheimer's disease (AD). We previously reported the first generation of quinoline-based PDE5 inhibitors for the treatment of AD. However, the short in vitro microsomal stability rendered them unsuitable drug candidates. Here we report a series of new quinoline-based PDE5 inhibitors. Among them, compound 4b, 8-cyclopropyl-3-(hydroxymethyl)-4-(((6-methoxypyridin-3-yl)methyl)amino)quinoline-6-carbonitrile, shows a PDE5 IC50 of 20 nM and improved in vitro microsomal stability (t1/2 = 44.6 min) as well as excellent efficacy in restoring long-term potentiation, a type of synaptic plasticity to underlie memory formation, in electrophysiology experiments with a mouse model of AD. These results provide an insight into the development of a new class of PDE5 inhibitors for the treatment of AD.


Assuntos
Doença de Alzheimer , Quinolinas , Camundongos , Animais , Inibidores da Fosfodiesterase 5/farmacologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Plasticidade Neuronal , Doença de Alzheimer/tratamento farmacológico , Quinolinas/farmacologia , Quinolinas/uso terapêutico
6.
J Obstet Gynaecol Res ; 49(8): 2185-2187, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37269089

RESUMO

Pregnancy epulis is a common and benign vascular tumor that reaches 5% of pregnant women; it respects adjacent structures, such as bone, teeth, and sinus mucosa. This paper reports a rare case of extensive pregnancy epulis with alveolar bone lysis, tooth displacement, and sinusal floor lysis. A 23-year-old pregnant woman with 23 weeks of amenorrhea was referred to the Department of Oral and Maxillofacial Surgery with a large maxillary mass and spontaneous bleeding, causing difficulty in speaking and swallowing. Due to the rapid development, the stage of pregnancy, and the need for a sure diagnosis of a benign lesion, a surgical excision was performed. After 1 month, the patient recovered from swallowing and speaking. Pregnancy epulis can be locally aggressive and involve alveolar bone. Biopsy allows to confirm the diagnosis. Surgery during pregnancy or birth waiting should be well ponderated in correlation with the size of the tumor and the delay to birth.


Assuntos
Reabsorção Óssea , Doenças da Gengiva , Neoplasias , Humanos , Gravidez , Feminino , Adulto Jovem , Adulto , Parto
7.
Br J Neurosurg ; 37(5): 1143-1145, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33095073

RESUMO

We report a case of a needlefish jaws retained near the C5-C6 joint that was associated with chronic pain and inflammation and seen confirmed by FDG-PET scan. Two unsuccessful surgeries using an anterior approach were complicated by vascular and nerve injuries. We used image-guided surgery with a posterior approach.


Assuntos
Beloniformes , Corpos Estranhos , Animais , Humanos , Tomografia Computadorizada por Raios X , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/cirurgia , Arcada Osseodentária
8.
Perfusion ; 38(6): 1308-1310, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35580365

RESUMO

An allergy to insect stings is one of the most frequent causes of anaphylactic reactions. Such reactions can be fatal, even on the first reaction, although it very rarely happens. The use of veno-arterial extracorporeal membrane oxygenation (VA ECMO) in refractory anaphylactic shock was previously described. We report a case of a 31-year-old female who presented with refractory anaphylactic shock after bee stings without the presence of cutaneous manifestations other than the rashes in her neck. The toxic component of bee venom and systemic allergic response plays a vital role in pathophysiology. She did not respond to conventional advanced life support, but following urgent VA ECMO, she survived neurologically intact. Despite an uncommon indication for anaphylaxis, ECMO support may be possible and effective in patients with refractory shock.


Assuntos
Anafilaxia , Venenos de Abelha , Oxigenação por Membrana Extracorpórea , Mordeduras e Picadas de Insetos , Feminino , Animais , Abelhas , Anafilaxia/etiologia , Anafilaxia/terapia , Mordeduras e Picadas de Insetos/complicações , Mordeduras e Picadas de Insetos/terapia , Choque Cardiogênico
9.
Dermatol Surg ; 48(9): 905-911, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36054041

RESUMO

BACKGROUND: Eyelid basal cell carcinoma (BCC) is usually cured by surgery. However, for a minority of patients, extensive disease progression and recurrence contraindicate surgery or radiotherapy because of severe ocular morbidity. The hedgehog signaling pathway inhibitor vismodegib is becoming the key treatment for this specific form. OBJECTIVE: The aim of this review was to define the role of surgery after vismodegib treatment. MATERIALS AND METHODS: A literature search of the PubMed, Cochrane Library, ScienceDirect, and Embase databases was conducted for all articles published up to March 2021 to identify studies that examined treatment of BCC of the eyelid by vismodegib. RESULTS: Level 1 evidence was found for the use of vismodegib as neoadjuvant therapy in locally advanced eyelid BCC contraindicated to surgery and/or radiotherapy with a rather good tolerance of treatment. Level 3 evidence was found for the role of surgical excision of residual clinically suspicious lesions as for the indication of eyelid reconstruction after mapping or during residual tumoral resection if frozen sections or Mohs surgery were performed. CONCLUSION: Vismodegib is a well-tolerated treatment for advanced periorbital BCC. The hedgehog signaling pathway inhibitor vismodegib is a potential treatment option in patients with these challenging tumors.


Assuntos
Antineoplásicos , Carcinoma Basocelular , Neoplasias Cutâneas , Anilidas , Carcinoma Basocelular/tratamento farmacológico , Carcinoma Basocelular/cirurgia , Proteínas Hedgehog , Humanos , Piridinas , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/cirurgia
10.
Sensors (Basel) ; 22(6)2022 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35336553

RESUMO

Detection of bacterial pathogens is significant in the fields of food safety, medicine, and public health, just to name a few. If bacterial pathogens are not properly identified and treated promptly, they can lead to morbidity and mortality, also possibly contribute to antimicrobial resistance. Current bacterial detection methodologies rely solely on laboratory-based techniques, which are limited by long turnaround detection times, expensive costs, and risks of inadequate accuracy; also, the work requires trained specialists. Here, we describe a cost-effective and portable 3D-printed electrochemical biosensor that facilitates rapid detection of certain Escherichia coli (E. coli) strains (DH5α, BL21, TOP10, and JM109) within 15 min using 500 µL of sample, and costs only USD 2.50 per test. The sensor displayed an excellent limit of detection (LOD) of 53 cfu, limit of quantification (LOQ) of 270 cfu, and showed cross-reactivity with strains BL21 and JM109 due to shared epitopes. This advantageous diagnostic device is a strong candidate for frequent testing at point of care; it also has application in various fields and industries where pathogen detection is of interest.


Assuntos
Técnicas Biossensoriais , Escherichia coli , Bactérias , Técnicas Biossensoriais/métodos , Limite de Detecção , Impressão Tridimensional
11.
Ann Chir Plast Esthet ; 67(4): 245-248, 2022 Sep.
Artigo em Francês | MEDLINE | ID: mdl-35781394

RESUMO

Scarpa triangle defects with exposure of femoral bypass are challenging to treat. The authors present the case of a 46 years-old male with a groin defect of 10×18cm with an exposure on 5cm of an allograft of the deep femoral artery. Bypass was performed in emergency because of a limb ischemia with deep femoral artery thrombosis and aneurysm of the superficial femoral artery. The reconstructive surgery may propose a large musculo-cutaneous flap to fill the dead spaces surrounding the infected bypass, the flap should be vascularized by the deep femoral arteria, could not be the rectus abdominals flap because of the precedent abdominal incision. The homolateral pediculated ALT-flap with vastus lateral component appeared to be a good solution because of its versatility and the low morbidity of the donor site.


Assuntos
Retalho Perfurante , Procedimentos de Cirurgia Plástica , Virilha , Humanos , Masculino , Pessoa de Meia-Idade , Músculos , Retalhos Cirúrgicos , Coxa da Perna
12.
BMC Cancer ; 21(1): 360, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827483

RESUMO

BACKGROUND: The rate of toxic deaths related to induction chemotherapy in the treatment of locally advanced head and neck cancers is unacceptable and calls into question this therapeutic strategy, which is however highly effective in terms of rate and speed of response. The purpose of the study was to investigate predictive factors of toxicity of induction chemotherapy with docetaxel, cisplatin, and 5-fluorouracil (TPF) in locally advanced head and neck cancers (LAHNC). METHODS: Between June 2009 and December 2017, 113 patients treated consecutively with TPF were included retrospectively. Patients were receiving induction chemotherapy for either an inoperable cancer or laryngeal preservation. For inoperable cancer, induction chemotherapy was proposed to patients presenting either a large tumor with strong symptoms (dyspnea, dysphagia, pain) or a tumor with rapid progression. Risk factors were chosen among the initial patient and tumour characteristics and chemotherapy modalities. RESULTS: Eighty-nine patients (79%) were male; the median age was 58 years [32-71]. Sixty-nine (61%) patients were treated for inoperable cancer and 44 (39%) for laryngeal preservation. 45% had stage IVa cancer, 28% stage III and 25% stage IVb. Sixty percent of patients had a partial response after TPF, 22% had a complete response, 12% were stable, 5% were progressing, and 1% had a discordant response. Thirty-four patients (30%) received enteral feeding during induction chemotherapy with TPF. The possibility of oral feeding without a tube was predictive of a better response (p = 0.003). Seven (6%) patients died during TPF. There was an increased risk of death with preexisting liver dysfunction (liver dysmorphia on imaging or decrease prothrombin rate) (p = 0.032). There was an increased risk of grade ≥ 3 infection if an enteral feeding occurred during the period of induction chemotherapy (p = 0.03). CONCLUSIONS: TPF induction chemotherapy had an 82% objective response rate with 6% toxic deaths. Nutritional status and the presence of hepatic dysfunction are significant risk factors to be taken into account in therapeutic decisions.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Quimioterapia de Indução/métodos , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Feminino , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Taxoides/farmacologia , Taxoides/uso terapêutico
13.
Med Oral Patol Oral Cir Bucal ; 26(1): e28-e35, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32851983

RESUMO

BACKGROUND: Numerous biochemical datas support the noxious role of anti-inflammatory drugs on immune response. Those observations are often put forward for unfavorable evolution of odontogenic infection but has never been really proven in clinic. The aim of this study is to try to clarify this role based on the collection of the clinical course of odontogenic infections over a 10-year analysis period. MATERIAL AND METHODS: The investigators implemented a prospective observational study. The sample was composed of patients managed between January 2004 and December 2014 for severe odontogenic infection based on three criteria: hospital admission, intravenous antibiotic therapy, tooth extraction and collections drainage under general anesthesia. Clinical and pharmacological data were collected at admission, during hospitalization until discharged home. The population was first separated into two groups patients with or without anti-inflammatory drugs on admission, then on four groups (non-steroidal anti-inflammatory drugs, corticosteroids drugs, both and none on admission). Analysis were performed each time by univariate analysis, multivariate analysis and propensity score matching. RESULTS: Six hundred and fifty-three patients were included in the study, 329 (50%) patients report orally anti-inflammatory treatment before presenting to hospital, 50 (7.6%) received corticosteroids, 242 (37%) received NSAIDs and 37 (5.6%) both. Evolution is worsening for patients under anti-inflammatory drugs in term of hospitalization in ICU (p=0.016), number of surgeries (p=0.003), risk of tracheotomy (p=0.036), duration of hospitalization (p=0.005) and spaces involved by the infection (p<0.001). When separating patients into 4 groups, dysphonia and odynophagia are more frequent for patients under corticosteroid and NSAID (35.14%, p<0.001), mediastinal erythema is more frequent for patients under corticosteroid (16%, p=0.004), fever is more frequent for patients under NSAID (35.5%, p=0.032), pain is higher for patients under corticosteroids (p=0.024). But, in order to reduce bias, linked to factors of gravity, a regression weighted by propensity scores was performed and any group of patients is different from the others. CONCLUSIONS: Patients under anti-inflammatory drugs have more severe dental infection on admission and their complex evolution seems to be linked to the severity of infection on admission.


Assuntos
Anti-Inflamatórios , Preparações Farmacêuticas , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios não Esteroides , Humanos , Dor , Prognóstico
14.
BMC Cancer ; 20(1): 730, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32758188

RESUMO

BACKGROUND: Primary surgery is usually the mainstay treatment in early-stage oropharyngeal and oral cavity cancer. Typically, neck surgery is performed. Negative tumor margins are recommended (> 5 mm). If feasible, re-resection of any positive margin is preferred. Otherwise, postoperative radiotherapy is required. Adjuvant postoperative radiotherapy can be limited to the primary site for patients with pT1-T2 tumors and negative neck exploration. Currently, both fractionated external beam radiotherapy and brachytherapy can have a role in the postoperative management of early-stage oropharyngeal and oral cavity cancer with high risk margins. Another possible alternative could be postoperative stereotactic body radiotherapy (SBRT). The aim of this study is to evaluate postoperative SBRT in the treatment of early-stage oropharyngeal and oral cavity cancer with high risk margins. METHODS: The STEREO POSTOP study is a national, open-label, non-randomized phase II trial within the GORTEC network. Patients with early-stage oropharyngeal and oral cavity cancers with high risk margins indicating the need for postoperative radiation are eligible for enrollment. SBRT consists of a total dose of 36 Gy in 6 fractions over 2 weeks. The primary endpoint is severe late toxicity defined as 2-year toxicity of grade ≥ 3 according to CTCAE V4.03 classification. The secondary endpoints include acute toxicity (≤ 3 months), local and locoregional control, disease-free and overall survival, quality of life of patients, nutritional impact and predictive factors of toxicity. The experimental design chosen is a one-step Fleming plan design without interim analysis as the primary endpoint will be evaluated at a 2-year follow-up. Ninety patients will be recruited. The study was started in January 2018 with a 4-year enrollment period and an estimated completion in January 2024. DISCUSSION: This study is the first prospective trial to evaluate head and neck cancer postoperative SBRT in the setting of early-stage oropharyngeal and oral cavity cancers with high risk margins. SBRT is an attractive option because it delivers a highly conformal dose of radiation in a limited number of fractions (like brachytherapy but with less contraindication), with steep dose gradients resulting in reduced normal tissue irradiation and with a short overall treatment time. TRIAL REGISTRATION: Clinicaltrials.gov : NCT03401840 , registered on 17-1-2018. Identifier in French National Agency for the Safety of Medicines and Health Products (ANSM): N°ID - RCB 2017-A02058-45, registered on July 2017. Protocol version: Version 3 dated from 25th November 2019.


Assuntos
Neoplasias Bucais/radioterapia , Neoplasias Orofaríngeas/radioterapia , Radiocirurgia/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Adulto , Fracionamento da Dose de Radiação , França , Humanos , Margens de Excisão , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Ensaios Clínicos Controlados não Aleatórios como Assunto , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/cirurgia , Estudos Prospectivos , Radiocirurgia/efeitos adversos , Radioterapia Adjuvante , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/cirurgia
15.
J Chem Phys ; 152(11): 115101, 2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32199422

RESUMO

The degradation of fibrils under the influence of thermal fluctuations was studied experimentally by various groups around the world. In the first set of experiments, it was shown that the decay of fibril content, which can be measured by the ThT fluorescence assay, obeys a bi-exponential function. In the second series of experiments, it was demonstrated that when the monomers separated from the aggregate are not recyclable, the time dependence of the number of monomers belonging to the dominant cluster is described by a single-exponential function if the fraction of bound chains becomes less than a certain threshold. Note that the time dependence of the fraction of bound chains can be measured by tryptophan fluorescence. To understand these interesting experimental results, we developed a phenomenological theory and performed molecular simulation. According to our theory and simulations using the lattice and all-atom models, the time dependence of bound chains is described by a logistic function, which slowly decreases at short time scales but becomes a single exponential function at large time scales. The results, obtained by using lattice and all-atom simulations, ascertained that the time dependence of the fibril content can be described by a bi-exponential function that decays faster than the logistic function on short time scales. We have uncovered the molecular mechanism for the distinction between the logistic and bi-exponential behavior. Since the dissociation of the chain from the fibrils requires the breaking of a greater number of inter-chain contacts as compared to the breaking of the beta sheet structure, the decrease in the number of connected chains is slower than the fibril content. Therefore, the time dependence of the aggregate size is logistic, while the two-exponential behavior is preserved for the content of fibrils. Our results are in agreement with the results obtained in both sets of experiments.

16.
Dysphagia ; 35(3): 494-502, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31598793

RESUMO

Patients surgically treated for oral cancer are affected by several underestimated deglutition disorders risk factors. This study aims to characterize the level of these food oral processing (FOP) impairments in a group of patients treated by surgery for tongue cancer. Twenty-seven consecutive patients surgically treated for tongue cancer were evaluated concerning their chewing capacity (Mastication-test), and responded to questions concerning their capacity to bite, chew and manipulate food with their tongue, and their quality of life. According to the Mastication-test, 16 patients suffered total FOP incapacities (TI group), characterized by high tumor stage, invasive carcinological surgery and necessity of reconstructive surgery; 12 patients were partially or not impaired (PI/NI-group). Tongue movement score and number of dental units were lower in the TI group than in the PI/NI-group. Subjective FOP criteria were clearly impaired in the TI group and correlated with a poor oral health-related quality of life. One year after surgery, there is a decrease in BMI for TI group patients while the PI group patients had a significant increase in BMI. All patients surgically treated for oral cancer suffered FOP impairments, but not with the same severity. Totally impaired subjects are at higher risk from long-term malnutrition. Functional evaluation of FOP should form part of the post-operative follow-up for all patients suffering from tongue cancer, using a quick combined evaluation of chewing efficiency, oral health quality of life and nutritional status.


Assuntos
Transtornos de Deglutição/fisiopatologia , Deglutição/fisiologia , Mastigação/fisiologia , Complicações Pós-Operatórias/fisiopatologia , Neoplasias da Língua/cirurgia , Idoso , Transtornos de Deglutição/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Qualidade de Vida , Língua/fisiopatologia , Língua/cirurgia , Neoplasias da Língua/fisiopatologia
17.
Ann Chir Plast Esthet ; 64(3): 278-282, 2019 Jun.
Artigo em Francês | MEDLINE | ID: mdl-30739800

RESUMO

Mucosal melanoma is a rare malignant disease developed from melanocyte. We report the case of a patient with nasal cavity mucosal melanoma with a primary clinical and histological diagnosis of malignant lentigo with mucosal spreading. The presence of a c-Kit mutation, in a second lecture and the evolving nature of the lesion, reorientated the diagnosis of malignant lentigo to mucosal melanoma with skin extension. Extensive surgical resection and foramen free flap with costal graft reconstruction may have a local control of the disease. Yet, after one year, a regional evolution involving a parapharyngeal node was treated by stereotaxic radiotherapy. After 5 years, the patient was considered in clinical and radiological remission. Malignant lentigo with mucosal extension is a very rare situation, this diagnoses must be evoqued after setting mucosal melanoma diagnosis.


Assuntos
Melanoma/cirurgia , Cavidade Nasal/cirurgia , Neoplasias Nasais/cirurgia , Neoplasias Cutâneas/cirurgia , Idoso , Diagnóstico Diferencial , Humanos , Sarda Melanótica de Hutchinson/diagnóstico , Masculino , Melanoma/diagnóstico , Melanoma/genética , Mutação , Mucosa Nasal/cirurgia , Nariz/cirurgia , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/genética , Fotografação , Proteínas Proto-Oncogênicas c-kit/genética , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética
18.
Kidney Int ; 93(1): 221-230, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28941940

RESUMO

Chronic inflammation contributes to increased mortality in hemodialysis (HD) patients. YKL-40 is a novel marker of inflammation, tissue remodeling, and highly expressed in macrophages inside vascular lesions. Elevated levels of YKL-40 have been reported for HD patients but how it integrates into the proinflammatory mediator network as a predictor of mortality remains elusive. We studied serum YKL-40, Interleukin-6 (IL-6), high-sensitivity C-reactive protein, monocyte chemotactic protein-1 (MCP-1), and interferon-gamma induced protein-10 (IP-10) in 475 chronic hemodialysis patients. Patients were followed for mortality for a median of 37 [interquartile range: 25-49] months and checked for interrelation of the measured mediators. To plot cumulative incidence functions, patients were stratified into terciles per YKL-40, IL-6, MCP-1, and IP-10 levels. Multivariable Cox regression models were built to examine associations of YKL-40, IP-10, and MCP-1 with all-cause and cause-specific mortality. Net reclassification improvement was calculated for the final models containing YKL-40 and IL-6. Increased YKL-40 was independently associated with age, IP-10, and IL-6 serum levels. After adjustment for demographic and laboratory parameters, comorbidities, and IL-6, only YKL-40 significantly improved risk prediction for all-cause (hazard ratio 1.4; 95% confidence interval 1.1-1.8) and cardiovascular mortality (hazard ratio 1.5; 95% confidence interval 1.03-2.2). Thus, in contrast to other biomarkers of aberrant macrophage activation, YKL-40 reflects inflammatory activity, which is not covered by IL-6. Mechanistic and prospective studies are needed to test for causal involvement of YKL-40 and whether it might qualify as a therapeutic target.


Assuntos
Proteína 1 Semelhante à Quitinase-3/sangue , Mediadores da Inflamação/sangue , Falência Renal Crônica/mortalidade , Falência Renal Crônica/terapia , Diálise Renal/mortalidade , Idoso , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/diagnóstico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
19.
J Chem Phys ; 149(17): 175101, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30408975

RESUMO

We studied the refolding free energy landscape of 26 proteins using the Go-like model. The distance between the denaturated state and the transition state, X F, was calculated using the Bell theory and the nonlinear Dudko-Hummer-Szabo theory, and its relation to the geometrical properties of the native state was considered in detail. We showed that none of the structural parameters, such as the contact order, protein length, and radius of cross section, correlate with X F for all classes of proteins. To overcome this problem, we have introduced the nematic order parameter P 02, which describes the ordering of the structured elements of the native state. Due to its topologically global nature, P 02 is better than other structural parameters in describing the folding free energy landscape. In particular, P 02 displays a good correlation with X F extracted from the nonlinear theory for all three classes of proteins. Therefore, this parameter can be used to predict X F for any protein, if its native structure is known.


Assuntos
Proteínas/química , Termodinâmica , Modelos Moleculares , Dobramento de Proteína
20.
J Chem Phys ; 146(13): 135101, 2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28390358

RESUMO

The impact of the quenched force on protein folding pathways and free energy landscape was studied in detail. Using the coarse-grain Go model, we have obtained the low, middle, and high force regimes for protein refolding under the quenched force. The folding pathways in the low force regime coincide with the thermal ones. A clear switch from thermal folding pathways to force-driven pathways in the middle force regime was observed. The distance between the denatured state and transition state xf in the temperature-driven regime is smaller than in the force-driven one. The distance xf obtained in the middle force regime is consistent with the available experimental data suggesting that atomic force microscopy experiments deal with the force-regime which is just above the thermal one.


Assuntos
Modelos Químicos , Redobramento de Proteína , Proteínas/química , Simulação de Dinâmica Molecular , Fenômenos Físicos , Desnaturação Proteica , Termodinâmica
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