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1.
Eur J Med Genet ; 68: 104919, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38355093

RESUMO

Hereditary hemorrhagic telangiectasia (HHT), also known as Rendu-Osler-Weber disease, is a dominant inherited vascular disorder. The clinical diagnosis is based on the Curaçao criteria and pathogenic variants in the ENG and ACVRL1 genes are responsible for most cases of HHT. Four families with a negative targeted gene panel and selected by a multidisciplinary team were selected and whole-genome sequencing was performed according to the recommendations of the French National Plan for Genomic Medicine. Structural variations were confirmed by standard molecular cytogenetic analysis (FISH). In two families with a definite diagnosis of HHT, we identified two different paracentric inversions of chromosome 9, both disrupting the ENG gene. These inversions are considered as pathogenic and causative for the HHT phenotype of the patients. This is the first time structural variations are reported to cause HHT. As such balanced events are often missed by exon-based sequencing (panel, exome), structural variations may be an under-recognized cause of HHT. Genome sequencing for the detection of these events could be suggested for patients with a definite diagnosis of HHT and in whom no causative pathogenic variant was identified.


Assuntos
Telangiectasia Hemorrágica Hereditária , Humanos , Telangiectasia Hemorrágica Hereditária/diagnóstico , Telangiectasia Hemorrágica Hereditária/genética , Telangiectasia Hemorrágica Hereditária/patologia , Mutação , Endoglina/genética , Sequência de Bases , Cromossomos Humanos Par 9/genética , Receptores de Activinas Tipo II/genética
3.
J Intern Med ; 274(4): 351-62, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23772771

RESUMO

OBJECTIVE: Hereditary haemorrhagic telangiectasia (HHT) is a genetic disorder related to mutations in one of the coreceptors to the transforming growth factor-ß superfamily (ALK1 or endoglin). Besides the obvious vascular symptoms (epistaxis and arteriovenous malformations), patients have an unexplained high risk of severe bacterial infections. The aim of the study was to assess the main immunological functions of patients with HHT using the standard biological tests for primary immunodeficiencies. DESIGN, SETTING AND SUBJECTS: A prospective single-centre study of 42 consecutive adult patients with an established diagnosis of HHT was conducted at the National French HHT Reference Center (Lyon). Lymphocyte subpopulations and proliferation capacity, immunoglobulin levels and neutrophil and monocyte phagocytosis, oxidative burst and chemotaxis were assessed. RESULTS: Innate immunity was not altered in patients with HHT. With regard to adaptive immunity, significant changes were seen in immunological parameters: primarily, a lymphopenia in patients with HHT compared with healthy control subjects affecting mean CD4 (642 cells µL(-1) vs. 832 cells µL(-1) , P < 0.001), CD8 (295 cells µL(-1) vs. 501 cells µL(-1) , P < 0.0001) and natural killer (NK) cells (169 cells µL(-1) vs. 221 cells µL(-1) , P < 0.01), associated with increased levels of immunoglobulins G and A. This lymphopenia mainly concerned naïve T cells. Proliferation capacities of lymphocytes were normal. Lymphopenic patients had a higher frequency of iron supplementation but no increase in infection rate. Lower levels of immunoglobulin M and a higher rate of pulmonary arteriovenous malformations were found amongst patients with a history of severe infection. CONCLUSIONS: Patients with HHT exhibit immunological abnormalities including T CD4, T CD8 and NK cell lymphopenia and increased levels of immunoglobulins G and A. The observed low level of immunoglobulin M requires further investigation to determine whether it is a specific risk factor for infection in HHT.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Hipergamaglobulinemia/etiologia , Linfopenia/etiologia , Telangiectasia Hemorrágica Hereditária/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipergamaglobulinemia/imunologia , Imunidade Inata/genética , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Linfopenia/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Telangiectasia Hemorrágica Hereditária/genética , Telangiectasia Hemorrágica Hereditária/imunologia , Adulto Jovem
4.
Rev Med Interne ; 31(8): e10-2, 2010 Aug.
Artigo em Francês | MEDLINE | ID: mdl-20413191

RESUMO

We report a 80-year-old woman who presented with asthenia, confusion and abdominal pain, leading to a diagnosis of severe pneumonia complicated by a colonic pseudo-obstruction. The unfavourable outcome with antibiotic treatment and a recent past medical history of thoracic radiotherapy pointed to a possible diagnosis of radiation pneumonitis. Absence of other explanation and the rapid improvement with corticosteroids confirmed this rare and potentially serious diagnosis, especially among elderly people.


Assuntos
Glucocorticoides/uso terapêutico , Metilprednisolona/uso terapêutico , Idoso de 80 Anos ou mais , Feminino , Humanos , Pneumonite por Radiação , Índice de Gravidade de Doença
5.
J Diabetes Sci Technol ; 2(2): 213-20, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19885345

RESUMO

BACKGROUND: Current methods of glucose monitoring rely predominantly on enzymes such as glucose oxidase for detection. Phenylboronic acid receptors have been proposed as alternative glucose binders. A unique property of these molecules is their ability to bind glucose in a fully reversible covalent manner that facilitates direct continuous measurements. We examined (1) the ability of a phenylboronic-based sensor to measure glucose in blood and blood plasma and (2) the effect on measurement accuracy of a range of potential interferents. We also showed that the sensor is able to track glucose fluctuations occurring at rates mimicking those experienced in vivo. METHOD: In vitro static measurements of glucose in blood and blood plasma were conducted using holographic sensors containing acrylamide, N,N'-methylenebisacrylamide, 3-acrylamidophenylboronic acid, and (3-acrylamidopropyl) trimethylammonium chloride. The same sensors were also used for in vitro measurements performed under flow conditions. RESULTS: The opacity of the liquid had no affect on the ability of the optical sensor to measure glucose in blood or blood plasma. The presence of common antibiotics, diabetic drugs, pain killers, and endogenous substances did not affect the measurement accuracy, as shown by error grid analysis. Ex vivo flow experiments showed that the sensor is able to track changes accurately in concentration occurring in real time without lag or evidence of hysteresis. CONCLUSIONS: The ability of phenylboronic acid sensors to measure glucose in whole blood was demonstrated for the first time. Holographic sensors are ideally suited to continuous blood glucose measurements, being physically and chemically robust and potentially calibration free.

6.
Clin Chem ; 53(10): 1820-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17717127

RESUMO

BACKGROUND: We recently described a holographic optical sensor with improved selectivity for glucose over fructose that was based on a thin-film polymer hydrogel containing phenylboronic acid receptors. The aim of the present work was to measure glucose in human blood plasma as opposed to simple buffers and track changes in concentration at a rate mimicking glucose changes in vivo. METHODS: We used holographic sensors containing acrylamide, N,N'-methylenebisacrylamide, 3-acrylamidophenylboronic acid, and (3-acrylamidopropyl)trimethylammonium chloride to measure 7 human blood plasma samples at different glucose concentrations (3-33 mmol/L) in static mode. Separately, using a flow cell, the glucose concentration was varied at approximately 0.17-0.28 mmol(-1) x L(-1) x min(-1), and the sensor's ability to continuously monitor glucose was investigated over an extended period. RESULTS: We subjected the results of the ex vivo static measurements to error grid analysis. Of 46 measurements, 42 (91.3%) fell in zone A of a Clarke error grid, and the remainder (8.7%) fell in zone B. The ex vivo flow experiments showed that the sensor is able to accurately track changes in concentration occurring in real time without lag or evidence of hysteresis. CONCLUSIONS: We demonstrate the ability of a phenylboronic acid-based sensor to measure glucose in human blood plasma for the 1st time in vitro. Holographic glucose sensors can be used without recourse to recalibration. Their robust nature, coupled with their format flexibility, makes them an attractive alternative to conventional electrochemical enzyme-based methods of glucose monitoring for people with diabetes.


Assuntos
Glicemia/análise , Ácidos Borônicos , Acrilamida , Acrilamidas , Soluções Tampão , Holografia , Humanos , Hidrogéis , Compostos de Amônio Quaternário
7.
Ann Chir Plast Esthet ; 45(3): 377-84, 2000 Jun.
Artigo em Francês | MEDLINE | ID: mdl-10929464

RESUMO

The association of osteogenic stem cells to a synthetic carrier makes possible the elaboration of bioartificial tissue. Numerous phosphocalcic ceramics does not trigger a foreign body reaction when implanted in bone tissue and thus, a number of materials are available osteogenic stem cell carriers to replace the bone tissue. Several methods can be used to harvest these cells. Their multiplication in vitro can lead to the appearance of anomalies of their metabolism or their karyotype. The culture method also seems to have a major influence on their appearance. The presence of these anomalies could explain the variability of results in terms of bone extracellular matrix synthesis after cell reimplantation. The surgical technique used for the implantation is also of influence. A method suppressing the in vitro period has been developed to avoid any cell metabolism modification. This method allows for a very reproducible bone synthesis in ectopic site. The availability of human embryonic stem cells could help to develop cell graft techniques for bone reconstruction.


Assuntos
Materiais Biocompatíveis , Osso e Ossos/citologia , Osso e Ossos/cirurgia , Osteoblastos/fisiologia , Osteoblastos/transplante , Osteogênese/fisiologia , Procedimentos de Cirurgia Plástica/métodos , Transplante de Células-Tronco , Coleta de Tecidos e Órgãos , Técnicas de Cultura de Células , Humanos
8.
J Biomed Mater Res ; 48(3): 224-34, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10398025

RESUMO

Calcium phosphate coatings on dental implants enhance integration of the material. Resorption of the ceramic coatings has raised some concern about the behavior of the bone-implant interfaces after the coating disappearance. Substitution of the OH- ions by fluoride in the hydroxylapatite (HA) lattice makes the calcium phosphate more stable. We investigated the degradation rate of dental implants with 50- and 100-microm coatings of HA, fluorapatite (FA), or fluorhydroxylapatite (FHA). The implants were inserted in dog jaws and retrieved for histological analysis after 3, 6, and 12 months. The thickness of the calcium phosphate coatings was evaluated using an image analysis device. A relative resorption index and its standard deviation were studied. HA and FA coatings (even at 100-microm thickness) were almost totally degraded within the implantation period. In contrast, the FHA coatings did not show significant degradation during the same period. The standard deviation showed that the resorption process for FHA with thicknesses of 50 or 100 microm was the same. Such a difference was not observed between the 50- and 100-microm thick coatings of FA and HA. In conclusion, the FHA coatings showed good integration in the bone tissue and lasted much longer than classic calcium phosphate coatings.


Assuntos
Apatitas , Implantes Dentários , Materiais Dentários , Durapatita , Hidroxiapatitas , Animais , Cães
9.
Morphologie ; 82(256): 9-11, 1998.
Artigo em Francês | MEDLINE | ID: mdl-11928121

RESUMO

Pseudo-synovial membranes are found at the interface between bone and aseptically lost prostheses. They are supposed to be due to the release of material debris at the interface with bone. They are mostly composed of macrophages and giant cells, and some fibrocytes in the deep layer of the membrane. The different histological structures present in these membranes have been largely described. Very recently, Kadoya et al. have demonstrated that a lot of giant cells present in the pseudo-synovial membranes show a tartrate resistant acid phosphatase activity in the presence of more than 100 mM tartrate. They have also shown that some of these cells were responsible for bone degradation. We have studied the tartrate acid phosphatase activity of a series of 10 membranes containing various material debris: titanium alloy, stainless steel, polymethylmethacrylate, polyethylene. Many mono or multinucleated cells showed a TRAP activity in their lysosomes in the presence of a 400 mM tartrate concentration. In certain membranes, these cells showed a TRAP activity located in the nucleus. This study shows that the macrophage population is very heterogeneous and the difference between osteoclasts and giant cells may be unclear.


Assuntos
Fosfatase Ácida/metabolismo , Isoenzimas/metabolismo , Membrana Sinovial/citologia , Membrana Sinovial/enzimologia , Humanos , Fosfatase Ácida Resistente a Tartarato
10.
Biotech Histochem ; 68(6): 333-41, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8292657

RESUMO

Orthopedic biomaterials currently are made of metal alloy coated with one or more thin layers of dense or porous ceramic or metal. Sections of these materials implanted in human bone were made without altering the implant or bone-implant interfaces. Bone containing an implant was fixed and then embedded in polymethylmethacrylate. Thick sections were made using a cooled, low speed diamond saw, then ground and polished. Some were stained by fuchsin-toluidine staining solution, others were acid etched to reveal the structure of the metal contained in the prosthesis. Observation by reflected and transmitted light microscopy revealed microstructure of the implant material as well as features of the surrounding tissues.


Assuntos
Materiais Biocompatíveis/química , Osso e Ossos/citologia , Próteses e Implantes , Ligas , Materiais Biocompatíveis/metabolismo , Osso e Ossos/metabolismo , Durapatita , Humanos , Metilmetacrilatos , Microscopia/métodos , Inclusão do Tecido , Titânio/química
11.
Artigo em Francês | MEDLINE | ID: mdl-8122005

RESUMO

Thin coatings of calcium phosphate hydroxyapatite on metal alloys provide to these materials biological properties of calcium phosphates. We have analysed, using histological techniques or newly developed scanning electronic microscopy techniques, hip prostheses implanted into humans for periods from a few days up to twenty six months. The results of these analyses confirm the good osteointegration of these prostheses observed during clinical studies. Moreover, an active remodeling of the bone in contact with the ceramic-coating was observed. The coating was also concerned by the remodeling process and evolved once implanted.


Assuntos
Fêmur/ultraestrutura , Prótese de Quadril , Hidroxiapatitas , Osseointegração , Matriz Óssea/ultraestrutura , Remodelação Óssea , Humanos , Microscopia Eletrônica de Varredura , Fatores de Tempo
12.
Biomaterials ; 13(10): 668-74, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1330016

RESUMO

HA-coated hip prostheses were retrieved from elderly patients after death. Histological analysis, scanning electron microscopy and microanalysis by energy-dispersive X-ray spectrometry were performed on the same sections. These revealed good osseointegration of the implant material and evolution of bone and material.


Assuntos
Prótese de Quadril , Hidroxiapatitas/farmacologia , Próteses e Implantes , Titânio , Idoso , Ligas , Animais , Osso e Ossos/citologia , Membrana Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Cães , Durapatita , Matriz Extracelular/efeitos dos fármacos , Espaço Extracelular/efeitos dos fármacos , Fibroblastos/citologia , Humanos , Microscopia Eletrônica de Varredura , Osteoblastos/citologia
13.
J Bone Joint Surg Br ; 73(5): 732-40, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1654335

RESUMO

We examined specimens of hydroxyapatite-coated femoral prostheses from four patients who had died within nine months of implantation for fractured neck of femur. Histology showed newly formed immature bone overlying the hydroxyapatite coating with new trabeculae bridging to the endosteal bone layer. In the diaphysis, where there had been contact between the hydroxyapatite and the cortex, there was dense, firmly anchored bone with an haversian architecture. In other places the newly formed bone had a trabecular structure, containing bone marrow tissue with normal cellularity. It appeared that biological osseointegration had taken place.


Assuntos
Fraturas do Colo Femoral/patologia , Fraturas do Colo Femoral/cirurgia , Prótese de Quadril , Hidroxiapatitas , Osseointegração , Idoso , Idoso de 80 Anos ou mais , Materiais Biocompatíveis , Cimentos Ósseos , Durapatita , Feminino , Humanos , Pessoa de Meia-Idade , Desenho de Prótese , Propriedades de Superfície
14.
J Biomed Mater Res ; 22(3 Suppl): 257-68, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3235463

RESUMO

Pellets of well-characterized microporous hydroxyapatite (HA) ceramic were implanted in hamsters in two nonosseous sites: (1) in the fatty tissue of the gingival crease, far from bony tissue and (2) in intraperitoneal sites. The implants in site 1 were placed directly in contact with tissues, cells, and extracellular fluids while the implants in site 2 were placed in special chambers made of plexiglass cylinders covered in both ends with millipore filters, preventing contact with tissues and cells, but not with extracellular fluids. The hamsters were sacrificed and the implants recovered after 8, 16, 30, 150, and 365 days. The pellets were characterized using x-ray diffraction, infrared absorption, thermogravimetry, scanning and transmission electron microscopy, and calcium and phosphate analyses before and after implantation. Physicochemical analyses of HA ceramic implants before and after implantation demonstrated the formation of new material which was significantly different from the HA ceramic in terms of the following: (a) morphology (size of shape) of crystals; (b) intimate association of the inorganic phase of the new material with an organic phase similar to inorganic/organic association in bone; (c) the inorganic phase of the new material is a CO3-apatite, similar to that of bone, while the HA in ceramic is CO3-free; (d) electron diffraction of apatite of new material is similar to that of bone apatite. This study also demonstrated that the new material associated with the HA ceramics implanted in two different nonosseous sites were identical in spite of the differences in their microenvironment (cellular and acellular).


Assuntos
Cerâmica/análise , Hidroxiapatitas/análise , Próteses e Implantes , Animais , Materiais Biocompatíveis , Carbonatos/análise , Cricetinae , Fêmur/análise , Espectrofotometria Infravermelho , Termogravimetria , Difração de Raios X
15.
Bull Assoc Anat (Nancy) ; 70(210): 35-6, 1986 Sep.
Artigo em Francês | MEDLINE | ID: mdl-3442703

RESUMO

By opposition to the anterior branches of spinal nerves which are constituted by motor, sensitive and autonomic fibers, some of the posterior branches have not or have few of sensitive territory: C1, C5, C6, C7, D1, L4, L5 are like that. This particularity ought to be reflected in their histogram. In a first analyse authors study number of fibers, in a second their caliber.


Assuntos
Fibras Nervosas/ultraestrutura , Nervos Espinhais/anatomia & histologia , Contagem de Células , Humanos
16.
J Biol Buccale ; 12(3): 259-65, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6594337

RESUMO

Experimental periodontal disease was induced in golden hamsters by feeding the animals with a Keyes 2 000 diet. The aim of the present study was to investigate the effect of 3-methoxy 5,7,3',4'-tetrahydroxyflavan (ME), a flavanoid derivative, on periodontally induced changes by this diet which was fed ad libitum to half of the animals for 2 months prior to the start of drug therapy. The animals were then divided into 4 groups: A) control animals on normal diet; B) ME-treated (200 mg/kg 3 times a week i.p.) animals on normal diet; C) animals on Keyes 2 000 diet; D) ME-treated (200 mg/kg 3 times a week i.p.) animals on Keyes 2 000 diet. ME inhibited the diminution of bone volume as measured morphometrically. The growth of dental plaque as evaluated by a sensitive index (PII) appeared to be retarded by ME. The average PII in the ME-treated animals reached after 2 months of diet remained unchanged during the drug therapy period (4 months); whereas it was significantly increased in the group C hamsters. The biochemical data further suggest that the resorption process of the alveolar bone was decreased by ME.


Assuntos
Flavonoides/uso terapêutico , Periodontite/tratamento farmacológico , Animais , Catequina/análogos & derivados , Cricetinae , Índice de Placa Dentária , Dieta , Avaliação Pré-Clínica de Medicamentos , Masculino , Mesocricetus , Periodontite/etiologia , Fatores de Tempo
17.
Artigo em Espanhol | LILACS | ID: lil-10825

RESUMO

Se examinaron 13.181 ninos en el Area Medica y 13.471 en el Area Odontologica, encontrando 15,5% y 63,7% respectivamente de patologia. Se considera necesario extender los estudios a los ninos en edad pre-escolar, implementar concomitantemente un programa de Educacion para la Salud y la creacion de servicios especializados en Ortopedia y Ortodoncia


Assuntos
Criança , Humanos , Serviços de Saúde Escolar
18.
Artigo em Espanhol | BINACIS | ID: bin-35521

RESUMO

Se examinaron 13.181 ninos en el Area Medica y 13.471 en el Area Odontologica, encontrando 15,5% y 63,7% respectivamente de patologia. Se considera necesario extender los estudios a los ninos en edad pre-escolar, implementar concomitantemente un programa de Educacion para la Salud y la creacion de servicios especializados en Ortopedia y Ortodoncia


Assuntos
Criança , Humanos , Serviços de Saúde Escolar
19.
Bull Assoc Anat (Nancy) ; 65(191): 383-92, 1981 Dec.
Artigo em Francês | MEDLINE | ID: mdl-7344736

RESUMO

Thymic and splenic extracts rich in FOA-KURLOFF (F.K.) body cells, obtained from guinea-pigs treated with oestrogen, were added to rat testis or ovaries in culture. Controls were prepared with extracts from thymus and spleen of non treated animals and from kidneys of treated or non treated animals. After five hours the level of sexual hormones and the germinal cells were studied. The F.K. substance has no effect on germinal cells and on progesterone and testosterone secretion. The F.K. substance induces a significative decrease of oestrogen secretion. In an other paper we established that F.K. bodies induced a hyperactivity of internal theca folliculi and of ovarian interstitial cells. It is a false image of activity in connection with a hypersecretion of FSH. The F.K. substance inhibits oestrogen synthesis.


Assuntos
Ovário/efeitos dos fármacos , Testículo/efeitos dos fármacos , Extratos do Timo/farmacologia , Animais , Estrogênios/metabolismo , Feminino , Cobaias , Masculino , Técnicas de Cultura de Órgãos , Progesterona/metabolismo , Ratos , Ratos Endogâmicos , Maturação do Esperma/efeitos dos fármacos , Testosterona/metabolismo
20.
C R Seances Acad Sci III ; 292(3): 293-8, 1981 Jan 19.
Artigo em Francês | MEDLINE | ID: mdl-6781779

RESUMO

The thymus and the spleen of guinea Pigs treated with oestrogen were rich in cells showing a special inclusion, the Foa-Kurloff body cell (F.K.). Thymic, spleen and renal cellular extracts were obtained by tissue crushing and ultra-centrifugation from healthy or oestrogen treated animals. The extracts were added to carcinomatous (HeLa) or to non-carcinomatous cells (MRC5 fibroblasts or foetal human lung cells). The thymic extracts in the non-treated animals and the splenic extracts rich in F.K. body cells induced an inhibition in the growth of carcinomatous cells. These effects were increased with the thymus extracts rich in F.K. bodies. The thymic inclusion of F.K. seems therefore to concentrate tumorous thymic fractions.


Assuntos
Cobaias/imunologia , Imunidade Inata , Neoplasias/veterinária , Animais , Extratos Celulares/imunologia , Células Cultivadas , Estrogênios/farmacologia , Humanos , Rim/fisiologia , Neoplasias/imunologia , Baço/fisiologia , Timo/fisiologia
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