Microrheological comparison of melanoma cells by atomic force microscopy.

Melanoma is one of the most severe cancers due to its great potential to form metastasis. Recent studies showed the importance of mechanical property assessment in metastasis formation which depends on the cytoskeleton dynamics and cell migration. Although cells are considered purely elastic, they are viscoelastic entities. Microrheology atomic force microscopy (AFM) enables the assessment of elasticity and viscous properties, which are relevant to cell behavior regulation. The current work compares the mechanical properties of human neonatal primary melanocytes (HNPMs) with two melanoma cell lines (WM793B and 1205LU cells), using microrheology AFM. Immunocytochemistry of F-actin filaments and phosphorylated focal adhesion kinase (p-FAK) and cell migration assays were performed to understand the differences found in microrheology AFM regarding the tumor cell lines tested. AFM revealed that HNPMs and tumor cell lines had distinct mechanical properties. HNPMs were softer, less viscous, presenting a higher power-law than melanoma cells. Immunostaining showed that metastatic 1205LU cells expressed more p-FAK than WM793B cells. Melanoma cell migration assays showed that WM73B did not close the gap, in contrast to 1205LU cells, which closed the gap at the end of 23 h. These data seem to corroborate the high migratory behavior of 1205LU cells. Microrheology AFM applied to HNPMs and melanoma cells allowed the quantification of elasticity, viscous properties, glassy phase, and power-law properties, which have an impact in cell migration and metastasis formation. AFM study is important since it can be used as a biomarker of the different stages of the disease in melanoma.

Mechanical Properties of Colorectal Cancer Cells Determined by Dynamic Atomic Force Microscopy: A Novel Biomarker.

Colorectal cancer (CRC) has been addressed in the framework of molecular, cellular biology, and biochemical traits. A new approach to studying CRC is focused on the relationship between biochemical pathways and biophysical cues, which may contribute to disease understanding and therapy development. Herein, we investigated the mechanical properties of CRC cells, namely, HCT116, HCT15, and SW620, using static and dynamic methodologies by atomic force microscopy (AFM). The static method quantifies Young's modulus; the dynamic method allows the determination of elasticity, viscosity, and fluidity. AFM results were correlated with confocal laser scanning microscopy and cell migration assay data. The SW620 metastatic cells presented the highest Young's and storage moduli, with a defined cortical actin ring with distributed F-actin filaments, scarce vinculin expression, abundant total focal adhesions (FAK), and no filopodia formation, which could explain the lessened migratory behavior. In contrast, HCT15 cells presented lower Young's and storage moduli, high cortical tubulin, less cortical F-actin and less FAK, and more filopodia formation, probably explaining the higher migratory behavior. HCT116 cells presented Young's and storage moduli values in between the other cell lines, high cortical F-actin expression, intermediate levels of total FAK, and abundant filopodia formation, possibly explaining the highest migratory behavior.

[Diagnostic approach and therapeutic management of hyperthyroidism]. / Démarche diagnostique et prise en charge thérapeutique de l'hyperthyroïdie.

Hyperthyroidism is a frequent clinical situation that can be expressed by various signs and it is generally easy to diagnose. This review proposes to explain the diagnostic approach that affects therapeutic management by separating diseases with homogeneous and nodular thyroid.

[Graves' orbitopathy: diagnosis, epidemiology and treatments]. / L'orbitopathie basedowienne: diagnostic, épidémiologie et principes de traitement.

Graves' orbitopathy is the most common extra-thyroid complication of Graves' disease and can be a potentially severe affection, therefore requiring multidisciplinary treatment support according to clinical activity and severity assessments. This review proposes to determine physiopathological mechanisms, epidemiology and therapeutic management of Graves' orbitopathy.

[Evaluation of a woman's care program after pre-eclampsia]. / Évaluation d'un parcours de soin chez la femme au décours d'une prééclampsie.

INTRODUCTION: The medical treatment of preeclampsia is well structured in its acute phase but the required follow-up with patients in post-partum is discussed. However, preeclampsia is associated with an increased risk of cardiovascular morbi-mortality in the long term. In order to optimize the post-partum treatment, a care program has been developed for these patients in the city of Nantes, France. This includes a check-up of the cardiovascular risks at a day hospital. Our study presents the first results of this program. METHODS: The study included 134 patients who were diagnosed with preeclampsia between October 2016 and January 2019 in the Nantes area, France, and took part in the program within the year following their childbirth. A descriptive analysis was first carried out and then a multivariate logistic regression model was used to investigate the risk factors for persistent high blood pressure after preeclampsia. RESULTS: The study detected 28 cases of persistent hypertension (20.9%), 34 cases of obesity (25.3%) and 1 case of diabetes. Hypertension was predominantly diastolic, mild and sometimes masked (35.7%). In a third of the cases (32.1%), the hypertension was secondary. High blood pressure was found to be more frequent in older patients (OR: 2.26; 95% CI: 1.25-4.11, p=0.072), patients from sub-Saharan Africa (OR: 11.52; 95% CI: 2.67-49.86, p=0.01) and multiparous patients (OR: 7.82; 95% CI: 1.15-53.21, p=0.035). CONCLUSION: The study confirmed that this care program enables an earlier detection and therefore treatment of the cardiovascular risk factors of these young women.

[Anorexia nervosa: Abnormalities in hematological and biochemical parameters]. / Anorexie mentale : anomalies des paramètres hématologiques et biochimiques.

Abnormalities of hematological and biochemical parameters are various and frequent during anorexia nervosa, and are mainly related to malnutrition, weight loss, and compensatory purgative behaviors. They are most often moderate and reversible through appropriate nutritional and weight rehabilitation, as well as well-conducted symptomatic treatment. Severe abnormalities are rarer, but are potentially serious or even fatal. Isolated moderate anemia and leukopenia are frequently noted, with thrombocytopenia being less frequent. Severe, bi-cytopenic, pancytopenic, and spinal cord injury are less common. They can be explained by the gelatinous transformation of the bone marrow caused by malnutrition. Biochemical abnormalities are typically hydroelectrolytic disorders (hypokalemia, hyponatremia, metabolic alkalosis), acute or chronic renal failure, elevated transaminases, risk of potentially severe hypoglycemia, and elevated lipid parameters. During the refeeding syndrome, hypophosphatemia is characteristic and may be associated with hypomagnesemia and hypocalcemia, and thiamine deficiency. Malnutrition can also lead to alterations in hormone status, including hypothyroidism, hypercorticism and hypogonadism, which may be involved in the development of serious bone conditions such as osteoporosis. These abnormalities should be routinely investigated, monitored, and corrected during anorexia nervosa. Early and multidisciplinary management of this eating disorder is essential to prevent chronicity of the disorder and the potential severity of these abnormalities.

Hybrid Epithelial-Mesenchymal Phenotypes Are Controlled by Microenvironmental Factors.

Epithelial-to-mesenchymal transition (EMT) has been associated with cancer cell heterogeneity, plasticity, and metastasis. However, the extrinsic signals supervising these phenotypic transitions remain elusive. To assess how selected microenvironmental signals control cancer-associated phenotypes along the EMT continuum, we defined a logical model of the EMT cellular network that yields qualitative degrees of cell adhesions by adherens junctions and focal adhesions, two features affected during EMT. The model attractors recovered epithelial, mesenchymal, and hybrid phenotypes. Simulations showed that hybrid phenotypes may arise through independent molecular paths involving stringent extrinsic signals. Of particular interest, model predictions and their experimental validations indicated that: (i) stiffening of the extracellular matrix was a prerequisite for cells overactivating FAK_SRC to upregulate SNAIL and acquire a mesenchymal phenotype and (ii) FAK_SRC inhibition of cell-cell contacts through the receptor-type tyrosine-protein phosphatases kappa led to acquisition of a full mesenchymal, rather than a hybrid, phenotype. Altogether, these computational and experimental approaches allow assessment of critical microenvironmental signals controlling hybrid EMT phenotypes and indicate that EMT involves multiple molecular programs. SIGNIFICANCE: A multidisciplinary study sheds light on microenvironmental signals controlling cancer cell plasticity along EMT and suggests that hybrid and mesenchymal phenotypes arise through independent molecular paths.

Melanoma in the Eyes of Mechanobiology.

Skin is the largest organ of the human body with several important functions that can be impaired by injury, genetic or chronic diseases. Among all skin diseases, melanoma is one of the most severe, which can lead to death, due to metastization. Mechanotransduction has a crucial role for motility, invasion, adhesion and metastization processes, since it deals with the response of cells to physical forces. Signaling pathways are important to understand how physical cues produced or mediated by the Extracellular Matrix (ECM), affect healthy and tumor cells. During these processes, several molecules in the nucleus and cytoplasm are activated. Melanocytes, keratinocytes, fibroblasts and the ECM, play a crucial role in melanoma formation. This manuscript will address the synergy among melanocytes, keratinocytes, fibroblasts cells and the ECM considering their mechanical contribution and relevance in this disease. Mechanical properties of melanoma cells can also be influenced by pigmentation, which can be associated with changes in stiffness. Mechanical changes can be related with the adhesion, migration, or invasiveness potential of melanoma cells promoting a high metastization capacity of this cancer. Mechanosensing, mechanotransduction, and mechanoresponse will be highlighted with respect to the motility, invasion, adhesion and metastization in melanoma cancer.

Roux-en-Y gastric bypass, but not sleeve gastrectomy, decreases plasma PCSK9 levels in morbidly obese patients.

AIM: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a master regulator of low-density lipoprotein cholesterol (LDL-C) metabolism, acting as an endogenous inhibitor of the LDL receptor. While it has been shown that bariatric surgery differentially affects plasma LDL-C levels, little is known of its effects on plasma PCSK9 concentrations. Therefore, the present study aimed to: (i) investigate the effect of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) on plasma PCSK9 concentrations; and (ii) correlate baseline or postoperative plasma PCSK9 concentration variations with anthropometric and metabolic parameters. METHODS: Fasting plasma PCSK9 levels were measured by ELISA in morbidly obese patients before and 6 months after bariatric surgery. Patients were recruited from three prospective cohorts (in Nantes and Colombes in France, and Antwerp in Belgium). RESULTS: A total of 156 patients (34SG, 122RYGB) were included. Plasma PCSK9, LDL-C and non-high-density lipoprotein cholesterol (non-HDL-C) levels were significantly reduced after RYGB (-19.6%, -16.6% and -19.5%, respectively; P<0.0001), but not after SG. In all patients, postoperative PCSK9 change was positively correlated with fasting plasma glucose (FPG; r=0.22, P=0.007), HOMA-IR (r=0.24, P=0.005), total cholesterol (r=0.17, P=0.037) and non-HDL-C (r=0.17, P=0.038) variations, but not LDL-C. In contrast to what was observed for glucose parameters (FPG, HOMA-IR), correlation between PCSK9 and non-HDL-C changes after RYGB was independent of total weight loss. CONCLUSION: RYGB, but not SG, promotes a significant reduction in plasma PCSK9 levels, and such changes in circulating PCSK9 levels after RYGB appear to be more associated with glucose improvement than with lipid homoeostasis parameters.

Emergence and multiple reassortments of French 2015-2016 highly pathogenic H5 avian influenza viruses.

From November 2015 to August 2016, 81 outbreaks of highly pathogenic (HP) H5 avian influenza virus were detected in poultry farms from South-Western France. These viruses were mainly detected in farms raising waterfowl, but also in chicken or guinea fowl flocks, and did not induce severe signs in waterfowl although they did meet the HP criteria. Three different types of neuraminidases (N1, N2 and N9) were associated with the HP H5 gene. Full genomes sequences of 24 H5HP and 6 LP viruses that circulated in the same period were obtained by next generation sequencing, from direct field samples or after virus isolation in SPF embryonated eggs. Phylogenetic analyses of the eight viral segments confirmed that they were all related to the avian Eurasian lineage. In addition, analyses of the "Time of the Most Recent Common Ancestor" showed that the common ancestor of the H5HP sequences from South-Western France could date back to early 2014 (±1 year). This pre-dated the first detection of H5 HP in poultry farms and was consistent with a silent circulation of these viruses for several months. Finally, the phylogenetic study of the different segments showed that several phylogenetic groups could be established. Twelve genotypes of H5HP were detected implying that at least eleven reassortment events did occur after the H5HP cleavage site emerged. This indicates that a large number of co-infections with both highly pathogenic H5 and other avian influenza viruses must have occurred, a finding that lends further support to prolonged silent circulation.

Histologically Proven Bronchial Neuroendocrine Tumors in MEN1: A GTE 51-Case Cohort Study.

OBJECTIVE: To evaluate the natural history of MEN1-related bronchial endocrine tumors (br-NETs) and to determine their histological characteristics, survival and causes of death. br-NETs frequency ranges from 3 to 13% and may reach 32% depending on the number of patients evaluated and on the criteria required for diagnosis. METHODS: The 1023-patient series of symptomatic MEN1 patients followed up in a median of 48.7 [35.5-59.6] years by the Groupe d'étude des Tumeurs Endocrines was analyzed using time-to-event techniques. RESULTS: br-NETs were found in 51 patients (4.8%, [95% CI 3.6-6.2%]) and were discovered by imaging in 86% of cases (CT scan, Octreoscan, Chest X-ray, MRI). Median age at diagnosis was 45 years [28-66]. Histological examination showed 27 (53%) typical carcinoids (TC), 16 (31%) atypical carcinoids (AC), 2 (4%) large cell neuroendocrine carcinomas (LCNEC), 3(6%) small cell neuroendocrine carcinomas (SCLC), 3(6%) TC associated with AC. Overall survival was not different from the rest of the cohort (HR 0.29, [95% CI 0.02-5.14]). AC tended to have a worse prognosis than TC (p = 0.08). Seven deaths were directly related to br-NETs (three AC, three SCLC and one LCNEC). Patients who underwent surgery survived longer (p = 10-4) and were metastasis free, while 8 of 14 non-operated patients were metastatic. There were no operative deaths. CONCLUSIONS: Around 5% of MEN1 patients develop br-NETs. br-NETs do not decrease overall survival in MEN1 patients, but poorly differentiated and aggressive br-NETs can cause death. br-NETs must be screened carefully. A biopsy is essential to operate on patients in time.

Competitive Adsorption of Plasma Proteins Using a Quartz Crystal Microbalance.

Proteins that get adsorbed onto the surfaces of biomaterials immediately upon their implantation mediate the interactions between the material and the environment. This process, in which proteins in a complex mixture compete for adsorption sites on the surface, is determined by the physicochemical interactions at the interface. Competitive adsorption of bovine serum albumin (BSA), fibronectin (Fn), and collagen type I (Col I), sequentially and from mixtures, was investigated so as to understand the performances of different surfaces used in biomedical applications. A quartz crystal microbalance with dissipation was used to monitor the adsorption of these proteins onto two materials used in functional bone replacement, a titanium alloy (Ti6Al4V) and Ti6Al4V physisorbed with poly(sodium styrenesulfonate) [poly(NaSS)], and three controls, gold, poly(desaminotyrosyltyrosine ethyl ester carbonate) [poly(DTEc)], and polystyrene (PS). In experiments with individual proteins, the adsorption was the highest with Fn and Col I and the least with BSA. Also, protein adsorption was the highest on poly(NaSS) and Ti6Al4V and the least on poly(DTEc). In sequential adsorption experiments, protein exchange was observed in BSA + Fn, Fn + Col I, and BSA + Col I sequences but not in Fn + BSA and Col I + BSA because of the lower affinity of BSA to surfaces relative to Fn and Col I. Protein adsorption was the highest with Col I + Fn on hydrophobic surfaces. In experiments with protein mixtures, with BSA & Fn, Fn appears to be preferentially adsorbed; with Fn & Col I, both proteins were adsorbed, probably as multilayers; and with Col I & BSA, the total amount of protein was the highest, greater than that in sequential and individual adsorption of the two proteins, probably because of the formation of BSA and Col I complexes. Protein conformational changes induced by the adsorbing surfaces, protein-protein interactions, and affinities of proteins appear to be the important factors that govern competitive adsorption. The findings reported here will be useful in understanding the host response to surfaces used for implants.

Unraveling the intrafamilial correlations and heritability of tumor types in MEN1: a Groupe d'étude des Tumeurs Endocrines study.

BACKGROUND: MEN1, which is secondary to the mutation of the MEN1 gene, is a rare autosomal-dominant disease that predisposes mutation carriers to endocrine tumors. Most studies demonstrated the absence of direct genotype-phenotype correlations. The existence of a higher risk of death in the Groupe d'étude des Tumeurs Endocrines-cohort associated with a mutation in the JunD interacting domain suggests heterogeneity across families in disease expressivity. This study aims to assess the existence of modifying genetic factors by estimating the intrafamilial correlations and heritability of the six main tumor types in MEN1. METHODS: The study included 797 patients from 265 kindred and studied seven phenotypic criteria: parathyroid and pancreatic neuroendocrine tumors (NETs) and pituitary, adrenal, bronchial, and thymic (thNET) tumors and the presence of metastasis. Intrafamilial correlations and heritability estimates were calculated from family tree data using specific validated statistical analysis software. RESULTS: Intrafamilial correlations were significant and decreased along parental degrees distance for pituitary, adrenal and thNETs. The heritability of these three tumor types was consistently strong and significant with 64% (s.e.m.=0.13; P<0.001) for pituitary tumor, 65% (s.e.m.=0.21; P<0.001) for adrenal tumors, and 97% (s.e.m.=0.41; P=0.006) for thNETs. CONCLUSION: The present study shows the existence of modifying genetic factors for thymus, adrenal, and pituitary MEN1 tumor types. The identification of at-risk subgroups of individuals within cohorts is the first step toward personalization of care. Next generation sequencing on this subset of tumors will help identify the molecular basis of MEN1 variable genetic expressivity.

MEN1 disease occurring before 21 years old: a 160-patient cohort study from the Groupe d'étude des Tumeurs Endocrines.

CONTEXT: Multiple endocrine neoplasia Type-1 (MEN1) in young patients is only described by case reports. OBJECTIVE: To improve the knowledge of MEN1 natural history before 21 years old. METHODS: Obtain a description of the first symptoms occurring before 21 years old (clinical symptoms, biological or imaging abnormalities), surgical outcomes related to MEN1 Neuro Endocrine Tumors (NETs) occurring in a group of 160 patients extracted from the "Groupe d'étude des Tumeurs Endocrines" MEN1 cohort. RESULTS: The first symptoms were related to hyperparathyroidism in 122 cases (75%), pituitary adenoma in 55 cases (34%), nonsecreting pancreatic tumor (NSPT) in 14 cases (9%), insulinoma in 20 cases (12%), gastrinoma in three cases (2%), malignant adrenal tumors in 2 cases (1%), and malignant thymic-NET in one case (1%). Hyperparathyrodism was the first lesion in 90 cases (56%). The first symptoms occurred before 10 years old in 22 cases (14%) and before 5 years old in five cases (3%). Surgery was performed before age 21 in 66 patients (41%) with a total of 74 operations: pituitary adenoma (n = 9, 16%), hyperparathyroidism (n = 38, 31%), gastrinoma (n = 1, 33%), NSPT (n = 5, 36%), and all cases of insulinoma, adrenal tumors, and thymic-NET. One patient died before age 21 due to a thymic-NET. Overall, lesions were malignant in four cases. CONCLUSIONS: Various MEN1 lesions occurred frequently before 21 years old, but mainly after 10 years of age. Rare, aggressive tumors may develop at any age. Hyperparathyroidism was the most frequently encountered lesion but was not always the first biological or clinical abnormality to appear during the course of MEN1.

[Systemic sarcoidosis after treatment with pegylated interferon-alpha]. / Sarcoïdose systémique au décours d'un traitement par interféron-alpha pégylé

A few cases of sarcoidosis have been reported in the course of chronic hepatitis C, with or without alpha-interferon treatment. We report a 54-year-old woman who presented a typical sarcoidosis in this context. The sarcoidosis involved skin, lungs and eyes. There are data in the literature supporting a pathogenic link between alpha-interferon and sarcoidosis: alpha-interferon possessing a non-specific immunologic inductor. The treatment of the sarcoidosis in this context is difficult and has to be adjusted to both the severity of the sarcoidosis and the viral hepatitis. Although sarcoidosis induced by alpha-interferon is rare, clinicians must be aware of this association.

Physiological traits of Penicillium glabrum strain LCP 08.5568, a filamentous fungus isolated from bottled aromatized mineral water.

Penicillium glabrum is a ubiquitous fungus distributed world wide. This fungus is a frequent contaminant in the food manufacturing industry. Environmental factors such as temperature, water activity and pH have a great influence on fungal development. In this study, a strain of P. glabrum referenced to as LCP 08.5568, has been isolated from a bottle of aromatized mineral water. The effects of temperature, a(w) and pH on radial growth rate were assessed on Czapeck Yeast Agar (CYA) medium. Models derived from the cardinal model with inflection [Rosso et al., 1993 An unexpected correlation between cardinal temperatures of microbial growth highlighted by a new model. J. Theor. Bio. 162, 447-463.] were used to fit the experimental data and determine for each factor, the cardinal parameters (minimum, optimum and maximum). Precise characterisation of the growth conditions for such a fungal contaminant, has an evident interest to understand and to prevent spoilage of food products.

[Travelers' knowledge of vaccines. A survey including 400 people having consulted an international vaccination center]. / Connaissances des voyageurs à propos des vaccins. Enquête auprès de 400 personnes consultantes d'un centre de vaccinations internationales.

UNLABELLED: The authors conducted a survey in an international vaccination centre. The aim of the study was to assess the travelers' knowledge of vaccines and to check their health record to determine the vaccination rate. We used a self-administered questionnaire and added vaccination certificates to the document. RESULTS: Most of the travelers knew about complications due to vaccinations, but ignored their contraindications. Knowledge decreased over the age of thirty. The travelers agreed with antihepatitis B vaccination and only 10% mentioned the risk of multiple sclerosis. The list of compulsory vaccinations and their schedule were well-known but some of the travelers ignored their vaccine status and said they trusted their general practitioner. Only 40% of people over 20years of age were able to present their national or international vaccination certificate, a reason for underestimating the vaccination rate. CONCLUSION: It would be necessary to have a "World Health Organization" type vaccination certificate available for all French people over 20years of age, while improving the smart health card and training practitioners to better inform their patients about vaccinations.