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1.
Microb Pathog ; 185: 106399, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37884212

RESUMO

The cause of death of Saint-Louis is not known, but recent findings indicated that he presented scurvy and inflammatory jaw disease, which has been associated with infection by oral commensals. Here, we have the exceptional opportunity to analyze the relics of the viscera of King Saint-Louis. A 4.3 g sample from the viscera relics of King Saint-Louis conserved in Versailles' cathedral was subjected to radiocarbon dating, electronic and optic microscopy, and elementary, palynological, molecular, proteomics and microbiological analyses including specific PCR and v3v4 16 S rRNA gene amplification prior to large-scale sequencing using an Illumina MiSeq instrument. The measured radiocarbon age was Cal 1290 CE-1400, which was compatible with that of the viscera of St Louis viscera, considering the addition of lime, incense and vegetables within the human organs. Elemental and palynological analyses confirmed a medieval embalming process. Proteomics analysis identified mainly human muscle and blood proteins. Specific PCR for plague, amoebiasis, shigellosis and typhoid fever was negative. C. sputigena was identified as the main pathogenic species representing 10.8 % of all microbial sequences. In contrast, C. sputigena was found in only 0.001 % of samples sequenced in our center, and the 23 positive human samples showed a dramatically lower abundance (0.02-2.6 %). In the literature, human infections with C. sputigena included odontitis, dental abscess, sinusitis, thoracic infections and bacteremia, particularly in immunocompromised patients with oral and dental diseases consistent with recent analysis of King Saint-Louis' jaw. C. sputigena, a commensal of the mouth that is potentially pathogenic and responsible for fatal bacteremia, may have been the cause of the king's death.


Assuntos
Bacteriemia , Escorbuto , Masculino , Humanos , Causas de Morte , Bacteriemia/microbiologia , França
2.
PLoS One ; 14(10): e0224138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31648281

RESUMO

Thyroid calcification is frequent in thyroid nodules. The aim of our study was to evaluate the prevalence of calcifications in thyroid tissue samples of patients with various thyroid diseases, and to identify their composition according to their localization. Among 50 thyroid samples included, 56% were malignant (papillary carcinoma) and 44% were benign (adenoma, multinodular goiter, Graves' disease, sarcoidosis). Calcifications were found in 95% of samples using polarised light microscopy, whereas only 12% were described in initial pathological reports. Three types were individualised and analyzed by infrared spectrometry (µFTIR): colloid calcifications composed of calcium oxalate, capsular calcifications and psammoma bodies, both composed of calcium phosphate. Of notice, psammoma bodies characterized by FE-SEM were composed of concentric structure suggesting a slow process for crystal deposition. Calcium phosphates were found only in malignant samples whereas calcium oxalate was not associated with a define pathology. Proliferation assessed by KI67 staining was high (33% of positive follicles), and RUNX2, OPN, and CD44 positive staining were detected in thyrocytes with a broad variation between samples. However, thyrocyte proliferation and differentiation markers were not associated with the number of crystals. TRPV5 and CaSR expression was also detected in thyrocytes. mRNA transcripts expression was confirmed in a subgroup of 10 patients, altogether with other calcium transporters such as PMCA1 or Cav1.3. Interestingly, TRPV5 mRNA expression was significantly associated with number of colloid calcifications (rho = -0.72; p = 0.02). The high prevalence of calcium oxalate crystals within colloid gel raises intriguing issues upon follicle physiology for calcium and oxalate transport.


Assuntos
Calcinose/epidemiologia , Calcinose/patologia , Carcinoma Papilar/fisiopatologia , Neoplasias da Glândula Tireoide/fisiopatologia , Nódulo da Glândula Tireoide/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
3.
JAMA Dermatol ; 155(7): 789-796, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31116362

RESUMO

Importance: Calcific uremic arteriolopathy (CUA), a rare, potentially fatal, disease with calcium deposits in skin, mostly affects patients with end-stage renal disease who are receiving dialysis. Chemical composition and structure of CUA calcifications have been poorly described. Objectives: To describe the localization and morphologic features and determine the precise chemical composition of CUA-related calcium deposits in skin, and identify any mortality-associated factors. Design, Setting, and Participants: A retrospective, multicenter cohort study was conducted at 7 French hospitals including consecutive adults diagnosed with CUA between January 1, 2006, and January 1, 2017, confirmed according to Hayashi clinical and histologic criteria. Patients with normal renal function were excluded. For comparison, 5 skin samples from patients with arteriolosclerosis and 5 others from the negative margins of skin-carcinoma resection specimens were also analyzed. Main Outcomes and Measures: Localization and morphologic features of the CUA-related cutaneous calcium deposits were assessed with optical microscopy and field-emission-scanning electron microscopy, and the chemical compositions of those deposits were evaluated with µ Fourier transform infrared spectroscopy, Raman spectroscopy, and energy dispersive radiographs. Results: Thirty-six patients (median [range] age, 64 [33-89] years; 26 [72%] female) were included, and 29 cutaneous biopsies were analyzed. Calcific uremic arteriolopathy and arteriolosclerosis skin calcifications were composed of pure calcium-phosphate apatite. Calcific uremic arteriolopathy vascular calcifications were always circumferential, found in small to medium-sized vessels, with interstitial deposits in 22 (76%) of the samples. A thrombosis, most often in noncalcified capillary lumens in the superficial dermis, was seen in 5 samples from patients with CUA. Except for calcium deposits, the vessel structure of patients with CUA appeared normal, unlike thickened arteriolosclerotic vessel walls. Twelve (33%) patients died of CUA. Conclusions and Relevance: Calcific uremic arteriolopathy-related skin calcifications were exclusively composed of pure calcium-phosphate apatite, localized circumferentially in small to medium-sized vessels and often associated with interstitial deposits, suggesting its pathogenesis differs from that of arteriolosclerosis. Although the chemical compositions of CUA and arteriolosclerosis calcifications were similar, the vessels' appearances and deposit localizations differed, suggesting different pathogenetic mechanisms.


Assuntos
Calciofilaxia/fisiopatologia , Pele/patologia , Calcificação Vascular/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Calciofilaxia/diagnóstico , Calciofilaxia/etiologia , Estudos de Coortes , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Microscopia , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Diálise Renal/métodos , Estudos Retrospectivos
4.
Clin Med Insights Ear Nose Throat ; 12: 1179550618821933, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30733633

RESUMO

The supposed relics of "Mary-Magdalene" are preserved in Provence (France) in an ancient tradition. They consist of a dry skull and a lock of hair. For the first time, they were officially subjected to an extensive medico-surgical examination by photogrammetry, high-magnification binocular lenses, scanning electron microscope, and energy-dispersive X-ray elemental analysis, to propose a full computer-aided facial reconstruction. The preliminary results are presented here.

5.
Front Physiol ; 8: 267, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28515694

RESUMO

Background and objective:FAM20A gene mutations result in enamel renal syndrome (ERS) associated with amelogenesis imperfecta (AI), nephrocalcinosis, gingival fibromatosis, and impaired tooth eruption. FAM20A would control the phosphorylation of enamel peptides and thus enamel mineralization. Here, we characterized the structure and chemical composition of unerupted tooth enamel from ERS patients and healthy subjects. Methods: Tooth sections were analyzed by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-Ray Diffraction (XRD), and X-Ray Fluorescence (XRF). Results: SEM revealed that prisms were restricted to the inner-most enamel zones. The bulk of the mineralized matter covering the crown was formed by layers with varying electron-densities organized into lamellae and micronodules. Tissue porosity progressively increased at the periphery, ending with loose and unfused nanonodules also observed in the adjoining soft tissues. Thus, the enamel layer covering the dentin in all ERS patients (except a limited layer of enamel at the dentino-enamel junction) displayed an ultrastructural globular pattern similar to one observed in ectopic mineralization of soft tissue, notably in the gingiva of Fam20a knockout mice. XRD analysis confirmed the existence of alterations in crystallinity and composition (vs. sound enamel). XRF identified lower levels of calcium and phosphorus in ERS enamel. Finally, EDS confirmed the reduced amount of calcium in ERS enamel, which appeared similar to dentin. Conclusion: This study suggests that, after an initial normal start to amelogenesis, the bulk of the tissue covering coronal dentin would be formed by different mechanisms based on nano- to micro-nodule aggregation. This evocated ectopic mineralization process is known to intervene in several soft tissues in FAM20A gene mutant.

6.
Sci Rep ; 6: 23038, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26987937

RESUMO

This paper reports on the voltage dependence of the magnetization reversal of a thin amorphous ferromagnetic TbFe film grown on a ferroelectric and piezoelectric BaTiO3 single crystal. Magneto-optical measurements, at macroscopic scale or in a microscope, demonstrate how the ferroelectric BaTiO3 polarisation history influences the properties of the perpendicularly magnetized TbFe film. Unpolarised and twinned regions are obtained when the sample is zero voltage cooled whereas flat and saturated regions are obtained when the sample is voltage cooled through the ferroelectric ordering temperature of the BaTiO3 crystal, as supported by atomic force microscopy experiments. The two steps involved in the TbFe magnetization reversal, namely nucleation and propagation of magnetic domain walls, depend on the polarisation history. Nucleation is associated to coupling through strains with the piezoelectric BaTiO3 crystal and propagation to pinning with the ferroelastic surface patterns visible in the BaTiO3 topography.

9.
Urology ; 86(6): 1090-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26433082

RESUMO

OBJECTIVE: To underline peculiar composition of kidney stones and to propose an epidemiologic study of urinary stones in West African countries, where epidemiologic studies are scarce. Only few data are available regarding stone composition in sub-Saharan countries. Recently, a set of 100 stones consecutively removed by surgery in the Department of Urology of the University Hospital of Ouagadougou in Burkina Faso were collected for physical analysis, which provided the opportunity to obtain an epidemiologic profile of stone composition in this country. MATERIALS AND METHODS: A total of 100 stones from 64 men, 22 women, 10 boys, and four girls were analyzed by morphologic examination, infrared spectroscopy, and electron microscopy in our laboratory. The results were considered by sex and separately for adults and children. RESULTS: Sixty-five percent of the 100 stones contained calcium oxalate as the main component. Interestingly, the second main component was opaline silica (18%). Furthermore, opaline silica was identified in any proportion in 48% of the stones. The prevalence was sex and age dependent. Opaline silica was detected as the main component in 42% of the nuclei, which underlines its role as one of the main components involved in the initiation of calculi in this country. CONCLUSION: For the first time, a dramatically high occurrence of a "scarce" urinary stone component, namely opaline silica, was reported in a series of consecutive calculi from a single country. We propose that a regular consumption of clay could be the origin of this phenomenon in these populations.


Assuntos
Cálculos Renais/química , Cálculos Renais/epidemiologia , Dióxido de Silício/análise , Adolescente , Adulto , Fatores Etários , Idoso , Burkina Faso/epidemiologia , Oxalato de Cálcio/análise , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Prevalência , Fatores Sexuais , Espectroscopia de Infravermelho com Transformada de Fourier , Adulto Jovem
10.
Nano Lett ; 14(9): 5044-51, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25119792

RESUMO

We investigate the organized formation of strain, ripples, and suspended features in macroscopic graphene sheets transferred onto corrugated substrates made of an ordered array of silica pillars with variable geometries. Depending on the pitch and sharpness of the corrugated array, graphene can conformally coat the surface, partially collapse, or lie fully suspended between pillars in a fakir-like fashion over tens of micrometers. With increasing pillar density, ripples in collapsed films display a transition from random oriented pleats emerging from pillars to organized domains of parallel ripples linking pillars, eventually leading to suspended tent-like features. Spatially resolved Raman spectroscopy, atomic force microscopy, and electronic microscopy reveal uniaxial strain domains in the transferred graphene, which are induced and controlled by the geometry. We propose a simple theoretical model to explain the structural transition between fully suspended and collapsed graphene. For the arrays of high density pillars, graphene membranes stay suspended over macroscopic distances with minimal interaction with the pillars' apexes. It offers a platform to tailor stress in graphene layers and opens perspectives for electron transport and nanomechanical applications.

11.
Sci Rep ; 3: 1296, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23448897

RESUMO

During the Middle Ages, the partition of the cadaver of the elite members was a current practice, with highly technical treatment given to symbolic organs such as the heart. Considered mostly from a theoretical point of view, this notion of dilaceratio corporis has never been biologically explored. To assess the exact kind of embalming reserved to the heart, we performed a full biomedical analysis of the mummified heart of the English King Richard I (1199 A.D.). Here we show among other aspects, that the organ has been embalmed using substances inspired by Biblical texts and practical necessities of desiccation. We found that the heart was deposed in linen, associated with myrtle, daisy, mint, frankincense, creosote, mercury and, possibly, lime. Furthermore, the goal of using such preservation materials was to allow long-term conservation of the tissues, and good-smelling similar to the one of the Christ (comparable to the odor of sanctity).


Assuntos
Embalsamamento/história , Coração/microbiologia , Antropologia , História Medieval , Humanos , Espectrometria de Massas , Múmias/microbiologia , Miocárdio/química , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Preservação Biológica/história
12.
Urology ; 79(4): 786-90, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22112288

RESUMO

OBJECTIVE: Bacterial imprints are always observed on highly carbonated apatite kidney stones but not struvite kidney stones. Struvite and carbonated apatite stones with a high CO(3)(2-)/PO(4)(3-) rate are believed to develop from infections, but their structural differences at the mesoscopic scale lack explanation. METHODS: We investigated 17 urinary calculi composed mainly of struvite or carbonated apatite by Fourier transform infrared, scanning electron microscopy, and powder neutron diffraction techniques. RESULTS: Carbonated apatite but not struvite stones showed bacterial imprints. If the same stone contained both carbonated apatite and struvite components, bacterial imprints were observed on the carbonated apatite but not the struvite part. Moreover, neutron powder diffraction experiments revealed the crystal size of struvite stones were larger than that of carbonated apatite stones (250 ± 50 vs 50 nm). CONCLUSION: Bacterial imprints may appear more easily on kidney stones with small nanocrystals, such as carbonated apatite than with large nanocrystals, such as struvite. This approach may help identify bacteria contributing to stone formation, perhaps with negative results of urine culture.


Assuntos
Cálculos Renais/química , Compostos de Magnésio/metabolismo , Fosfatos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apatitas/metabolismo , Carbonato de Cálcio/metabolismo , Pré-Escolar , Feminino , Humanos , Cálculos Renais/microbiologia , Cálculos Renais/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Nanopartículas/química , Difração de Nêutrons , Difração de Pó , Espectroscopia de Infravermelho com Transformada de Fourier , Estruvita
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