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1.
Phys Rev Lett ; 126(19): 196407, 2021 May 14.
Article de Anglais | MEDLINE | ID: mdl-34047592

RÉSUMÉ

We report the observation of a nontrivial spin texture in Dirac node arcs, i.e., novel topological objects formed when Dirac cones of massless particles extend along an open one-dimensional line in momentum space. We find that such states are present in all the compounds of the tetradymite M_{2}Te_{2}X family (M=Ti, Zr, or Hf and X=P or As) regardless of the weak or strong character of the topological invariant. The Dirac node arcs in tetradymites are thus the simplest possible textbook example of a type-I Dirac system with a single spin-polarized node arc.

2.
Eur Rev Med Pharmacol Sci ; 24(6): 2811-2819, 2020 03.
Article de Anglais | MEDLINE | ID: mdl-32271398

RÉSUMÉ

OBJECTIVE: Intervertebral disc degeneration (IVDD) is mainly associated with a chronic process of the nucleus pulposus (NP) cells disabled. Also, it is accepted to be the basic result of low back pain. The role of phosphatase and tensin homolog (PTEN) in negatively regulating the Akt/PKB signaling, which is the major cell survival pathway, has been documented in previous studies. The present work aimed to investigate the role of PTEN inhibitor VO-OHpic (VO) in the protection of IVDD and to explore its potential mechanisms. PATIENTS AND METHODS: NP cells isolated from patients' lumbar discs were subjected to different concentrations of IL-1ß or H2O2 to establish NP cells degenerated model. Cell proliferation was analyzed by the Cell Counting Kit-8 (CCK-8) assay. The expression levels of collagen II, aggrecan, PTEN, PI3K, Akt, SOD1, SOD2, p16, and ß-galactosidase (ß-gal) were detected by Western blotting, immunofluorescence staining or RT-PCR. Flow cytometry was used to measure the ROS level and cell cycle distribution. RESULTS: Our research showed that collagen II, aggrecan, PI3K, and Akt markedly decreased in IL-1ß- or H2O2-induced degenerated NP cells. VO could reverse the effects of IL-1ß and H2O2 by the PTEN inhibition. Also, we found that VO increased the antioxidant enzymes SOD1, SOD2, CAT, GSH, POD production, and suppressed the ROS in the disc. Besides, data showed VO promoted NP cells proliferation by cell cycle mediation. CONCLUSIONS: These results suggest that VO treatment prevents NP degradation via restraining oxidative stress and increasing cell proliferation through the PTEN/Akt pathway in vitro. VO may become a novel cytokine for the therapy of IVDD in the future.


Sujet(s)
Antienzymes/pharmacologie , Dégénérescence de disque intervertébral/traitement médicamenteux , Composés organométalliques/pharmacologie , Phosphohydrolase PTEN/antagonistes et inhibiteurs , Protéines proto-oncogènes c-akt/antagonistes et inhibiteurs , Survie cellulaire/effets des médicaments et des substances chimiques , Cellules cultivées , Humains , Dégénérescence de disque intervertébral/métabolisme , Dégénérescence de disque intervertébral/anatomopathologie , Nucleus pulposus/effets des médicaments et des substances chimiques , Nucleus pulposus/métabolisme , Nucleus pulposus/anatomopathologie , Phosphohydrolase PTEN/génétique , Phosphohydrolase PTEN/métabolisme , Protéines proto-oncogènes c-akt/génétique , Protéines proto-oncogènes c-akt/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques
3.
Zhonghua Shao Shang Za Zhi ; 35(11): 828-832, 2019 Nov 20.
Article de Chinois | MEDLINE | ID: mdl-31775475

RÉSUMÉ

The repair strategy after organs injuries has always been a hot topic in the field of regenerative medicine. Traditional injury repair measures mainly promote tissue repair through mesenchymal stem cells and various growth factors, but these strategies have been constrained in the aspects of security and economy. Hence, there is an urgent need to find new ways to promote tissue repair and regeneration. There have been a lot of evidences showing that the immune system plays an important role in tissue regeneration and repair. In recent years, more and more studies have been done on adaptive immunity in tissue repair, especially the regulatory T cells. Some evidences indicate that regulatory T cells participate in damage tissue repair and regeneration of multiple organs and tissue. This review briefly introduces the new advances in the repair effects and regulatory mechanism of regulatory T cells in different organ injuries, in order to provide new ideas for designing advanced repair materials with good immunoregulatory functions.


Sujet(s)
Régénération , Lymphocytes T régulateurs/immunologie , Cicatrisation de plaie/immunologie , Humains , Médecine régénérative/tendances
4.
Phys Rev Lett ; 120(20): 206401, 2018 May 18.
Article de Anglais | MEDLINE | ID: mdl-29864304

RÉSUMÉ

We report a de Haas-van Alphen (dHvA) effect study on the Dirac type-II semimetallic candidates MAl_{3} (where, M=V, Nb and Ta). The angular dependence of their Fermi surface (FS) cross-sectional areas reveals a remarkably good agreement with our first-principles calculations. Therefore, dHvA supports the existence of tilted Dirac cones with Dirac type-II nodes located at 100, 230 and 250 meV above the Fermi level ϵ_{F} for VAl_{3}, NbAl_{3} and TaAl_{3} respectively, in agreement with the prediction of broken Lorentz invariance in these compounds. However, for all three compounds we find that the cyclotron orbits on their FSs, including an orbit nearly enclosing the Dirac type-II node, yield trivial Berry phases. We explain this via an analysis of the Berry phase where the position of this orbit, relative to the Dirac node, is adjusted within the error implied by the small disagreement between our calculations and the experiments. We suggest that a very small amount of doping could displace ϵ_{F} to produce topologically nontrivial orbits encircling their Dirac node(s).

5.
Allergy ; 73(8): 1653-1661, 2018 Aug.
Article de Anglais | MEDLINE | ID: mdl-29319884

RÉSUMÉ

BACKGROUND: Due to high IgE recognition frequency and high allergenic activity, Der p 5 and Der p 21 are clinically important house dust mite (HDM) allergens. The objective of this study was to characterize the immunodominant IgE epitopes of Der p 5 and Der p 21 responsible for their high allergenic activity. METHODS: A panel of 12 overlapping peptides spanning the Der p 5 and Der p 21 sequence were synthesized to search for sequential IgE epitopes by direct testing for allergic patients' IgE reactivity. Peptide-specific antibodies raised in rabbits were used in inhibition studies for localizing conformational IgE epitopes which were visualized on the surfaces of the allergen structures by molecular modelling. IgE cross-reactivity between the allergens was investigated by IgE inhibition studies. RESULTS: Immunodominant IgE epitopes defined by allergic patients' IgE on Der p 5 and Der p 21 were primarily of the conformational, discontinuous type including N- and C-terminal portions of the protein. They could be located on each allergen on one area with similar localization, but despite similar structure of the allergens, no relevant IgE cross-reactivity could be detected. CONCLUSION: Our study shows that Der p 5 and Der p 21 contain a major conformational IgE epitope-containing area located on similar portions of their structure, but they lack relevant IgE cross-reactivity. These data are important for the development of modern allergy vaccines based on defined molecules for allergen-specific immunotherapy of HDM allergy.


Sujet(s)
Allergènes/immunologie , Antigènes de Dermatophagoides/composition chimique , Antigènes de Dermatophagoides/immunologie , Protéines d'arthropode/composition chimique , Protéines d'arthropode/immunologie , Réactions croisées/immunologie , Épitopes/composition chimique , Immunoglobuline E/immunologie , Pyroglyphidae/immunologie , Animaux , Protéines d'arthropode/synthèse chimique , Découverte de médicament , Cartographie épitopique , Épitopes/immunologie , Humains , Immunisation , Immunoglobuline E/sang , Immunoglobuline G/immunologie , Modèles moléculaires , Conformation moléculaire , Structure en hélice alpha , Pliage des protéines , Lapins , Vaccins synthétiques
6.
Oncogene ; 36(39): 5484-5496, 2017 09 28.
Article de Anglais | MEDLINE | ID: mdl-28534513

RÉSUMÉ

Protein disulfide isomerase a4 (PDIA4) is implicated in the growth and death of tumor cells; however, its molecular mechanism and therapeutic potential in cancer are unclear. Here, we found that PDIA4 expression was upregulated in a variety of tumor cell lines and human lung adenocarcinoma tissues. Knockdown and overexpression of PDIA4 in tumor cells showed that PDIA4 facilitated cell growth via the reduction of caspases 3 and 7 activity. Consistently, Lewis lung carcinoma cells overexpressing PDIA4 grew faster than did parental cells in tumor-bearing mice, as shown by a reduced survival rate, increased tumor size and metastasis, and decreased cell death and caspases 3 and 7 activity. PDIA4 knockdown resulted in opposite outcomes. Moreover, results obtained in mice with spontaneous hepatoma indicated that PDIA4 deficiency significantly reduced hepatic tumorigenesis and cyst formation and increased mouse survival, tumor death, and caspases 3 and 7 activity. Mechanistic studies illustrated that PDIA4 negatively regulated tumor cell death by inhibiting degradation and activation of procaspases 3 and 7 via their mutual interaction in a CGHC-dependent manner. Finally, we found that 1,2-dihydroxytrideca-5,7,9,11-tetrayne, a PDIA4 inhibitor, reduced tumor development via enhancement of caspase-mediated cell death in TSA tumor-bearing mice. These findings characterize PDIA4 as a negative regulator of cancer cell apoptosis and suggest that PDIA4 is a potential therapeutic target for cancer.


Sujet(s)
Caspases/métabolisme , Proenzymes/métabolisme , Protein Disulfide-Isomerases/métabolisme , Animaux , Lignée cellulaire tumorale , Femelle , Cellules HEK293 , Cellules HepG2 , Humains , Cellules Jurkat , Cellules MCF-7 , Mâle , Mélanome expérimental , Souris , Souris de lignée BALB C , Souris de lignée C57BL
7.
J Phys Condens Matter ; 29(2): 024004, 2017 Jan 18.
Article de Anglais | MEDLINE | ID: mdl-27861169

RÉSUMÉ

Magnetic susceptibility, electrical resistivity, and heat capacity results are reported for the chemical substitution series URu2Si2-x P x for [Formula: see text]. This study expands in detail on work recently reported in Gallagher et al (2016 Nat. Commun. 10712), which focused on the small x region of this substitution series. Measurements presented here reveal persistent hybridization between the f- and conduction electrons and strong variation of the low temperature behavior with increasing x. Hidden order and superconductivity are rapidly destroyed for [Formula: see text] and are replaced for [Formula: see text] by a region with Kondo coherence but no ordered state. Antiferromagnetism abruptly appears for [Formula: see text]. This phase diagram differs significantly from those produced by most other tuning strategies in URu2Si2, including applied pressure, high magnetic fields, and isoelectronic chemical substitution (i.e. Ru → Fe and Os), where hidden order and magnetism share a common phase boundary. Besides revealing an intriguing evolution of the low temperature states, this series provides a setting in which to investigate the influence of electronic tuning, where probes that are sensitive to the Fermi surface and the symmetry of the ordered states will be useful to unravel the anomalous behavior of URu2Si2.

8.
Transplant Proc ; 48(3): 716-9, 2016 Apr.
Article de Anglais | MEDLINE | ID: mdl-27234720

RÉSUMÉ

BACKGROUND: Previous studies have shown that kidney volume enhances the estimation of glomerular filtration rate (eGFR) in kidney donors. This study aimed to describe the phenomenon of compensatory hypertrophy after donor nephrectomy as measured on computerized tomographic (CT) scans. METHODS: An institutional Domain Specific Review Board (DSRB)-approved study involved approaching kidney donors to have a follow up CT scan from 6 months to 1 year after surgery; 29 patients participated; 55% were female. Clinical chart review was performed, and the patient's remaining kidney volume was measured before and after surgery based on CT scans. eGFR was determined with the use of the Modification of Diet in Renal Disease equation. RESULTS: Mean parenchymal volume of the remaining kidney for this population (mean age, 44.3 ± 8.5 y) was 204.7 ± 82.5 cc before surgery and 250.5 ± 113.3 cc after donor nephrectomy. Compensatory hypertrophy occurred in 79.3% of patients (n = 23). Mean increase in remaining kidney volume was 22.4 ± 23.2% after donor nephrectomy in healthy individuals. Over a median follow-up of 52.9 ± 19.8 months, mean eGFR was 68.9 ± 12.4 mL/min/1.73 m(2), with 24.1% of patients (n = 7) in chronic kidney disease grade 3. Absolute and relative change in kidney volume was not associated with sex, race, surgical approach, or background of hypertension (P = NS). There was a trend of decreased hypertrophy with increasing age (P = .5; Spearman correlation, -0.12). CONCLUSIONS: In healthy kidney donors, compensatory hypertrophy of the remaining kidney occurs in 79.3% of the patients, with an average increment of about 22.4%. Older patients may have a blunted compensatory hypertrophy response after surgery.


Sujet(s)
Hypertrophie/imagerie diagnostique , Donneur vivant , Néphrectomie/effets indésirables , Prélèvement d'organes et de tissus/effets indésirables , Tomodensitométrie/méthodes , Adaptation physiologique/physiologie , Adulte , Facteurs âges , Femelle , Débit de filtration glomérulaire , Humains , Hypertrophie/étiologie , Rein/imagerie diagnostique , Rein/physiopathologie , Tumeurs du rein/chirurgie , Transplantation rénale/méthodes , Mâle , Adulte d'âge moyen , Néphrectomie/méthodes , Insuffisance rénale chronique/chirurgie , Études rétrospectives , Prélèvement d'organes et de tissus/méthodes
9.
Phys Rev Lett ; 116(15): 157201, 2016 04 15.
Article de Anglais | MEDLINE | ID: mdl-27127982

RÉSUMÉ

We present the structural and magnetic properties of a new compound family, Mg_{2}RE_{3}Sb_{3}O_{14} (RE=Gd,Dy,Er), with a hitherto unstudied frustrating lattice, the "tripod kagome" structure. Susceptibility (ac, dc) and specific heat exhibit features that are understood within a simple Luttinger-Tisza-type theory. For RE=Gd, we found long-ranged order (LRO) at 1.65 K, which is consistent with a 120° structure, demonstrating the importance of diople interactions for this 2D Heisenberg system. For RE=Dy, LRO at 0.37 K is related to the "kagome spin ice" physics for a 2D system. This result shows that the tripod kagome structure accelerates the transition to LRO predicted for the related pyrochlore systems. For RE=Er, two transitions, at 80 mK and 2.1 K are observed, suggesting the importance of quantum fluctuations for this putative XY system.

10.
J Phys Condens Matter ; 28(14): 14LT01, 2016 Apr 13.
Article de Anglais | MEDLINE | ID: mdl-26953683

RÉSUMÉ

Results are reported for single crystal specimens of Hf2Te2P and compared to its structural analogue Zr2Te2P, which was recently proposed to be a potential reservoir for Dirac physics [1]. Both materials are produced using the iodine vapor phase transport method and the resulting crystals are exfoliable. The bulk electrical transport and thermodynamic properties indicate Fermi liquid behavior at low temperature for both compounds. Quantum oscillations are observed in magnetization measurements for fields applied parallel but not perpendicular to the c-axis, suggesting that the Fermi surfaces are quasi-two dimensional. Frequencies are determined from quantum oscillations for several parts of the Fermi surfaces. Lifshitz-Kosevich fits to the temperature dependent amplitudes of the oscillations reveal small effective masses, with a particularly small value [Formula: see text] for the α branch of Zr2Te2P. Electronic structure calculations are in good agreement with quantum oscillation results and illustrate the effect of a stronger spin-orbit interaction going from Zr to Hf. These results suggest that by using appropriate tuning parameters this class of materials may deepen the pool of novel Dirac phenomena.

11.
Nat Commun ; 7: 10712, 2016 Feb 19.
Article de Anglais | MEDLINE | ID: mdl-26891903

RÉSUMÉ

The heavy fermion intermetallic compound URu2Si2 exhibits a hidden-order phase below the temperature of 17.5 K, which supports both anomalous metallic behavior and unconventional superconductivity. While these individual phenomena have been investigated in detail, it remains unclear how they are related to each other and to what extent uranium f-electron valence fluctuations influence each one. Here we use ligand site substituted URu2Si(2-x)P(x) to establish their evolution under electronic tuning. We find that while hidden order is monotonically suppressed and destroyed for x≤0.035, the superconducting strength evolves non-monotonically with a maximum near x≈0.01 and that superconductivity is destroyed near x≈0.028. This behavior reveals that hidden order depends strongly on tuning outside of the U f-electron shells. It also suggests that while hidden order provides an environment for superconductivity and anomalous metallic behavior, it's fluctuations may not be solely responsible for their progression.

12.
Hong Kong Med J ; 21(2): 98-106, 2015 Apr.
Article de Anglais | MEDLINE | ID: mdl-25756275

RÉSUMÉ

OBJECTIVE: To evaluate the effectiveness of various orthotic treatments for patients with isolated medial compartment osteoarthritis. DESIGN: Prospective cohort study with sequential interventions. SETTING: University-affiliated hospital, Hong Kong. PATIENTS: From December 2010 to November 2011, 10 patients with medial knee osteoarthritis were referred by orthopaedic surgeons for orthotic treatment. All patients were sequentially treated with flat insole, lateral-wedged insole, lateral-wedged insole with subtalar strap, lateral-wedged insole with arch support, valgus knee brace, and valgus knee brace with lateral-wedged insole with arch support for 4 weeks with no treatment break. Three-dimensional gait analysis and questionnaires were completed after each orthotic treatment. MAIN OUTCOME MEASURES: The Western Ontario and McMaster Universities Arthritis Index (WOMAC), visual analogue scale scores, and peak and mean knee adduction moments. RESULTS: Compared with pretreatment, the lateral-wedged insole, lateral-wedged insole with arch support, and valgus knee brace groups demonstrated significant reductions in WOMAC pain score (19.1%, P=0.04; 18.2%, P=0.04; and 20.4%, P=0.02, respectively). The lateral-wedged insole with arch support group showed the greatest reduction in visual analogue scale score compared with pretreatment at 24.1% (P=0.004). Addition of a subtalar strap to lateral-wedged insoles (lateral-wedged insole with subtalar strap) did not produce significant benefit when compared with the lateral-wedged insole alone. The valgus knee brace with lateral-wedged insole with arch support group demonstrated an additive effect with a statistically significant reduction in WOMAC total score (-26.7%, P=0.01). Compliance with treatment for the isolated insole groups were all over 90%, but compliance for the valgus knee brace-associated groups was only around 50%. Gait analysis indicated statistically significant reductions in peak and mean knee adduction moments in all orthotic groups when compared with a flat insole. CONCLUSIONS: These results support the use of orthotic treatment for early medial compartment knee osteoarthritis.


Sujet(s)
Asiatiques/statistiques et données numériques , Démarche/physiologie , Gonarthrose/ethnologie , Gonarthrose/thérapie , Amplitude articulaire/physiologie , Sujet âgé , Orthèses de maintien , Études de cohortes , Femelle , Orthèses de pied , Hong Kong , Hôpitaux universitaires , Humains , Mâle , Adulte d'âge moyen , Orthèses , Gonarthrose/imagerie diagnostique , Mesure de la douleur , Pronostic , Études prospectives , Radiographie , Indice de gravité de la maladie , Résultat thérapeutique
13.
Genet Mol Res ; 14(1): 1393-403, 2015 Feb 13.
Article de Anglais | MEDLINE | ID: mdl-25730078

RÉSUMÉ

The micromolar calcium-activated neutral protease gene (CAPN1) is a physiological candidate gene for meat tenderness. Four previously identified single nucleotide polymorphism (SNP) markers located within the CAPN1 gene were evaluated for their associations with variation in the meat tenderness of a Chinese indigenous chicken breed, a higher meat quality breed (i.e., Qingyuan partridge chicken), and the commercial Recessive White chicken breed. Warner-Bratzler shear force measurements were used to determine tenderness phenotypes for all animals; intramuscular fat (IMF) content and rate of water loss in the breast muscles were also measured. Genotyping was performed by the polymerase chain reaction-ligase detection reaction method. Polymorphisms were identified for all markers, except CAPN1 2546. The frequency of allele T was zero, and allele C was fixed for CAPN1 2546 in the studied populations. The SNP CAPN1 3535 in the CAPN1 gene was significantly associated with tenderness and other meat quality traits, where animals inheriting the AA genotype had smaller shear force values, lower water loss rates, and higher IMF contents. Moreover, H1 (AAA) was the most advantageous haplotype for meat tenderness. The results of this study confirm some previously documented associations. Furthermore, novel associations have been identified that, following validation in other populations, could be incorporated into breeding programs to improve meat quality.


Sujet(s)
Calpain/génétique , Calpain/physiologie , Poulets/génétique , Viande , Polymorphisme de nucléotide simple , Allèles , Animaux , Sélection , Fréquence d'allèle , Marqueurs génétiques/génétique , Génotype , Haplotypes , Phénotype , Réaction de polymérisation en chaîne , Analyse de séquence d'ADN , Résistance au cisaillement
14.
Br J Cancer ; 110(1): 208-13, 2014 Jan 07.
Article de Anglais | MEDLINE | ID: mdl-24169348

RÉSUMÉ

BACKGROUND: Carcinoma of unknown primary (CUP) is a clinical presentation with a poor prognosis. Inflammation-based prognostic systems are stage-independent prognostic predictors in various malignancies. We aimed to assess the accuracy of the modified Glasgow Prognostic Score (mGPS), neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR) as objective prognostic models in CUP. METHODS: We derived inflammatory scores in 60 consecutive CUP referrals to the Imperial College oncology unit between 1996 and 2011. Patient demographics, treatment and staging data and full blood profiles were collected. An independent cohort of 179 patients presenting to the Taipei Veterens Hospital between 2000 and 2009 were used as a 'validation' data set. Uni- and multivariate survival analysis was used to predict the overall survival (OS). RESULTS: Sixty patients were included: median age 61 (range: 33-86); 51% men; median OS 5.9 months (0.7-42.9); 88% with distant metastases. On univariate analysis NLR >5 (P=0.04) and mGPS (score 1-2) (P=0.03) correlated with OS. Multivariate analysis demonstrated significant hazard ratios for NLR; 2.02 (CI 1.0-4.1) (P=0.04) and mGPS; 1.52 (CI 1.0-2.3) (P=0.03). These findings were reinforced by analysis of the validation data. CONCLUSION: NLR and mGPS are independent, externally validated prognostic markers in CUP, with superior objectivity compared with performance status.


Sujet(s)
Inflammation/anatomopathologie , Métastases d'origine inconnue/anatomopathologie , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Humains , Inflammation/sang , Mâle , Adulte d'âge moyen , Modèles statistiques , Stadification tumorale , Métastases d'origine inconnue/sang , Pronostic , Reproductibilité des résultats
15.
J Oral Rehabil ; 40(1): 43-50, 2013 Jan.
Article de Anglais | MEDLINE | ID: mdl-23121231

RÉSUMÉ

This investigation examined the cumulative survival rate of the implant-supported overdenture using two types of attachments in patients treated at Show Chwan Memorial Hospital Implant Center from 1992 to 2006. Fifty-one patients (30 men and 21 women) were treated with mandibular implant-supported overdentures. Attachment systems used were the Hader bar with bilateral, cast ERA attachments (Group A, 31 patients with 15 men and 16 women, 134 implants) and the Hader bar with bilateral, distal extension cantilevers (Group B, 20 patients with 15 men and 5 women, 85 implants). Two hundred and four implants remained at the end of the follow-up period. Among failed implants, 10 implants were in Group A (failure rate: 10/134 = 7·5%), whereas five implants were in Group B (failure rate: 5/85 = 5·9%). Sixty-six point seven per cent (10/15) of failed implants were placed in the distal anterior mandible, and 33·3% (5/15) were placed in the middle anterior mandible. Survival was also examined with respect to condition of the opposing arch. Patients wearing a maxillary removable partial denture had the highest implant failure rate (5/51 = 9·8%), whereas the failure rate of the maxillary complete denture group was only 5·7%. The most frequent need for maintenance was wear over patrix component of ERA or Hader clip (n = 56). Eight patients experienced connector fracture between ERA and Hader bar, and one experienced distal extension cantilever fracture. The implant-supported overdenture can be an effective and reliable alternative to the conventional complete mandibular denture. Fewer prosthetic complications were seen in overdentures retained with distal extension cantilever attachments.


Sujet(s)
Implants dentaires , Prothèse dentaire implanto-portée/instrumentation , Conception d'appareil de prothèse dentaire , Overdenture , Mâchoire édentée/rééducation et réadaptation , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Échec de restauration dentaire , Femelle , Humains , Mâle , Mandibule , Maxillaire , Adulte d'âge moyen , Études rétrospectives , Résultat thérapeutique
16.
Clin Exp Allergy ; 42(9): 1347-55, 2012 Sep.
Article de Anglais | MEDLINE | ID: mdl-22925321

RÉSUMÉ

BACKGROUND: The production of allergen-specific IgE antibodies is a hallmark of IgE-mediated allergy but the contribution of blood cells to allergen-specific IgE production in allergic patients has not been studied in detail. OBJECTIVE: Aim of this study was the characterization of IgE-producing cells in the blood of allergic patients and the determination of the amount of IgE antibodies which are produced by these cells in relation to total amounts of circulating specific IgE. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from allergic patients and cell populations were purified or depleted using magnetically labelled antibodies directed against specific cell surface markers (CD19, CD20, CD22, CD27, CD38, CD126, CD138, CD203c). Allergen-specific IgE was measured in serum samples and cell culture supernatants by quantitative ImmunoCAP measurements and by ELISA using purified recombinant allergens. IgE transcripts were detected using RT-PCR with primers specific for human IgE. RESULTS: We found that allergen-specific IgE levels in PBMC supernatants correlated strongly with specific serum IgE but represented less than 1% of circulating IgE. Depletion of basophils resulted in substantial reduction of allergen-specific IgE levels in PBMC culture supernatants suggesting that an important source of allergen-specific IgE in PBMC supernatants could be IgE derived from the surface of basophils. Newly synthesized IgE was derived from CD138+ plasma cells, but not from B and B memory cells, and accounted for only approximately 0.2% of circulating IgE in blood. CONCLUSION AND CLINICAL RELEVANCE: Our finding that the majority of allergen-specific IgE in the peripheral blood is not derived from IgE-secreting cells in the blood suggests local IgE production in tissues as a major source for allergen-specific IgE and possible target for therapeutic intervention.


Sujet(s)
Allergènes/immunologie , Spécificité des anticorps , Lymphocytes B/immunologie , Hypersensibilité immédiate/immunologie , Immunoglobuline E/biosynthèse , Plasmocytes/immunologie , Cellules cultivées , Cytométrie en flux , Humains , Immunoglobuline E/sang , Agranulocytes/immunologie , Agranulocytes/métabolisme , Syndécane-1/métabolisme
18.
Allergy ; 67(5): 609-21, 2012 May.
Article de Anglais | MEDLINE | ID: mdl-22339348

RÉSUMÉ

BACKGROUND: More than 90% of house dust mite-allergic patients are sensitized to the major Dermatophagoides pteronyssinus allergen, Der p 2. The aim of this study was to develop and characterize an allergy vaccine based on carrier-bound Der p 2 peptides, which should allow reducing IgE- and T-cell-mediated side-effects during specific immunotherapy (SIT). METHODS: Five Der p 2 peptides (P1-P5) were synthesized and analyzed regarding IgE reactivity and allergenic activity. Lymphoproliferative and cytokine responses induced with Der p 2 and Der p 2 peptides were determined in peripheral blood mononuclear cells from mite-allergic patients. Der p 2-specific IgG antibodies induced with carrier-bound Der p 2 peptides in mice and rabbits were tested for their capacity to inhibit IgE binding and basophil activation in allergic patients. RESULTS: Of five overlapping peptides (P1-P5) covering the Der p 2 sequence, two peptides (P2 and P4) were identified, which showed no relevant IgE reactivity, allergenic activity, and induced lower Der p 2-specific T-cell activation than Der p 2. However, when coupled to a carrier, P2 and P4 induced Der p 2-specific IgG antibodies in animals, which inhibited allergic patients' IgE binding to the allergen and allergen-induced basophil activation similar as antibodies induced with Der p 2. CONCLUSIONS: Carrier-bound Der p 2 peptides should allow avoiding IgE-mediated side-effects, and because of their low potential to activate allergen-specific T cells, they may reduce late-phase side-effects during SIT. Further, these peptides may be also useful for prophylactic vaccination.


Sujet(s)
Allergènes/immunologie , Anticorps bloquants/immunologie , Antigènes de Dermatophagoides/immunologie , Protéines d'arthropode/immunologie , Granulocytes basophiles/immunologie , Hypersensibilité/immunologie , Immunoglobuline G/immunologie , Peptides/immunologie , Séquence d'acides aminés , Animaux , Spécificité des anticorps/immunologie , Antigènes de Dermatophagoides/composition chimique , Protéines d'arthropode/composition chimique , Granulocytes basophiles/métabolisme , Cytokines/immunologie , Cytokines/métabolisme , Femelle , Hémocyanine/composition chimique , Humains , Immunoglobuline E/immunologie , Immunoglobuline E/métabolisme , Agranulocytes/immunologie , Agranulocytes/métabolisme , Activation des lymphocytes/immunologie , Souris , Souris de lignée BALB C , Données de séquences moléculaires , Peptides/composition chimique , Phosphodiesterases/métabolisme , Liaison aux protéines/immunologie , Pyroglyphidae/immunologie , Pyrophosphatases/antagonistes et inhibiteurs , Pyrophosphatases/métabolisme , Lapins , Lymphocytes T/immunologie , Lymphocytes T/métabolisme , Vaccins conjugués/immunologie
19.
J Int Med Res ; 40(6): 2394-400, 2012.
Article de Anglais | MEDLINE | ID: mdl-23321197

RÉSUMÉ

OBJECTIVE: A retrospective evaluation of the clinical outcome and technical feasibility of kyphoplasty for the treatment of very severe osteoporotic vertebral compression fracture (vsOVCF). METHODS: Patients with vsOVCF were treated with kyphoplasty and followed-up for 1 year. Vertebral body height variation, kyphotic angle, back pain (visual analogue scale [VAS]) and Oswestry disability index (ODI) were evaluated preoperatively, postoperatively, 1 month, 3 months and 1 year after treatment. RESULTS: In total, 35 patients (49 vertebrae) were treated with kyphoplasty. There were no cases of spinal or extraspinal injury, infection, bleeding, pulmonary embolism, epidural cement leakage, stroke or cardiac arrest as a result of treatment. There were significant postoperative improvements in all outcome measures (vertebral body height variation, kyphotic angle, VAS and ODI); these improvements were maintained during the follow-up period. CONCLUSION: Kyphoplasty is an effective and minimally invasive procedure for the treatment of vsOVCF.


Sujet(s)
Ciments osseux , Fractures par compression/chirurgie , Cyphoplastie , Fractures ostéoporotiques/chirurgie , Sujet âgé , Sujet âgé de 80 ans ou plus , Dorsalgie/chirurgie , Taille , Femelle , Humains , Cyphoplastie/effets indésirables , Vertèbres lombales/traumatismes , Vertèbres lombales/chirurgie , Mâle , Adulte d'âge moyen , Ostéoporose , Mesure de la douleur , Études rétrospectives , Fractures du rachis/chirurgie , Vertèbres thoraciques/traumatismes , Vertèbres thoraciques/chirurgie , Résultat thérapeutique
20.
Poult Sci ; 90(12): 2705-10, 2011 Dec.
Article de Anglais | MEDLINE | ID: mdl-22080007

RÉSUMÉ

China is particularly rich in goose genetic resources. Systematic study of the genetic diversity and origin of Chinese domestic geese will provide an important scientific basis for the conservation and utilization of these resources and for human history. The 521-bp control region (D-loop) of mitochondrial DNA from 26 goose breeds and 6 Landaise geese were sequenced. The results showed that the average haplotype diversity and nucleotide diversity of Chinese domestic geese were 0.1384 and 0.00029, respectively. Shared haplotype analysis and systematic evolution analysis revealed that Chinese domestic geese had 2 maternal origins. The Yili goose breed originated from the Greylag goose (Anser anser), and the other 25 domestic goose breeds originated from the swan goose (Anser cygnoides). An interesting finding was that 1 Linxian white goose and 1 Wanxi white goose shared the same H4 haplotype with the Rhine goose and the Landaise goose, which originated from the Greylag goose (A. anser). Further research on this finding is planned.


Sujet(s)
Évolution biologique , ADN mitochondrial/génétique , Oies/génétique , Variation génétique , Animaux , Chine , Démographie , Femelle , Haplotypes
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