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1.
Bull Entomol Res ; 109(5): 643-648, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30724140

RESUMEN

The tachinid fly Drino inconspicuoides (Diptera: Tachinidae) is an ovolarviparous endoparasitoid whose larvae develop in the host haemocoel and avoids the host immune system. In this study, we investigated the immune evasion mechanisms of this species during infestation in the host Mythimna separata (Lepidoptera: Noctuidae). We discovered a unique 'cloak' that surrounded D. inconspicuoides larvae that penetrated into the host and determined through genomic polymerase chain reaction analysis that this structure originated from the host rather than the tachinid. The 'cloak' contained both haemocytes and fat body cells from the host, with the haemocytes assembling around the larvae first and the fat body cells then covering the haemocyte layer, following which the two mixed. Living D. inconspicuoides larvae that were wrapped in the 'cloak' were not melanized whereas encapsulated dead larvae were melanized, suggesting that this structure contributes to the avoidance of host immune reactions.


Asunto(s)
Dípteros/crecimiento & desarrollo , Interacciones Huésped-Parásitos/inmunología , Evasión Inmune , Mariposas Nocturnas/inmunología , Mariposas Nocturnas/parasitología , Animales , Cuerpo Adiposo/citología , Hemocitos , Interacciones Huésped-Parásitos/fisiología , Larva/inmunología , Larva/parasitología , Mariposas Nocturnas/crecimiento & desarrollo , Análisis de Secuencia de ADN
2.
Chem Soc Rev ; 47(11): 3788-3803, 2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29714390

RESUMEN

Self-assembly is a crucial component in the bottom-up fabrication of hierarchical supramolecular structures and advanced functional materials. Control has traditionally relied on the use of encoded building blocks bearing suitable moieties for recognition and interaction, with targeting of the thermodynamic equilibrium state. On the other hand, nature leverages the control of reaction-diffusion processes to create hierarchically organized materials with surprisingly complex biological functions. Indeed, under non-equilibrium conditions (kinetic control), the spatio-temporal command of chemical gradients and reactant mixing during self-assembly (the creation of non-uniform chemical environments for example) can strongly affect the outcome of the self-assembly process. This directly enables a precise control over material properties and functions. In this tutorial review, we show how the unique physical conditions offered by microfluidic technologies can be advantageously used to control the self-assembly of materials and of supramolecular aggregates in solution, making possible the isolation of intermediate states and unprecedented non-equilibrium structures, as well as the emergence of novel functions. Selected examples from the literature will be used to confirm that microfluidic devices are an invaluable toolbox technology for unveiling, understanding and steering self-assembly pathways to desired structures, properties and functions, as well as advanced processing tools for device fabrication and integration.

3.
Eur J Gynaecol Oncol ; 38(3): 459-461, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29693892

RESUMEN

Lymphoepithelioma-like carcinoma (LELC) is a rare variant of carcinoma of the uterine cervix, of which Epstein-Barr virus (EBV) and/or human papilloma virus (HPV) may play an important role in the pathogenesis. The authors report a case of a patient with cervical LELC who was also examined for the presence of EBV and HPV. A 31-year-old Japanese female presented with irregular genital bleeding. The biopsy showed an invasive squamous cell carcinoma. Based on the clinical data, the patient was diagnosed as having squamous cervical carcinoma, and radical hysterectomy with ovarian conservation was performed. A diagnosis of cervical LELC was then made by histological methods. An additional examination revealed that the patient was infected with HPV types 16 and 71, but not infected with EBV.


Asunto(s)
Carcinoma/virología , Papillomaviridae/aislamiento & purificación , Neoplasias del Cuello Uterino/virología , Adulto , Carcinoma/diagnóstico , Femenino , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Neoplasias del Cuello Uterino/diagnóstico
4.
Phys Rev Lett ; 117(3): 037206, 2016 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-27472136

RESUMEN

Motivated by recent experiments on volborthite single crystals showing a wide 1/3-magnetization plateau, we perform microscopic modeling by means of density functional theory (DFT) with the single-crystal structural data as a starting point. Using DFT+U, we find four leading magnetic exchanges: antiferromagnetic J and J_{2}, as well as ferromagnetic J^{'} and J_{1}. Simulations of the derived spin Hamiltonian show good agreement with the experimental low-field magnetic susceptibility and high-field magnetization data. The 1/3-plateau phase pertains to polarized magnetic trimers formed by strong J bonds. An effective J→∞ model shows a tendency towards condensation of magnon bound states preceding the plateau phase.

6.
Oral Dis ; 21(2): 224-31, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24750447

RESUMEN

OBJECTIVES: Recently, the use of saliva as a diagnostic tool has gained considerable attention because it is non-invasive and easy to perform repeatedly. In this study, we focused on soluble molecules in saliva to establish a new diagnostic method for xerostomia. MATERIALS AND METHODS: Saliva was obtained from 90 patients with Sjögren's syndrome (SS), 22 patients with xerostomia associated with neurogenic/neuropsychiatric disorders and drugs (XND), 30 patients with radiation-induced xerostomia (RX), and 36 healthy controls. Concentrations of helper T (Th) cytokines in saliva were measured by flow cytometric analysis. Concentrations of secretory IgA (SIgA) and chromogranin A (CgA) were measured by ELISA. RESULTS: Unstimulated and stimulated whole saliva from patients with SS, XND, and RX was significantly reduced compared with controls. Th1 and Th2 cytokines from SS patients were significantly higher than controls. Furthermore, Th2 cytokines were closely associated with strong lymphocytic accumulation in salivary glands from SS patients, while Th1 and Th17 cytokines were negatively associated. SIgA levels were not significantly different between all patient groups and controls. CgA levels from XND patients were significantly higher than controls. CONCLUSIONS: The measurement of cytokines, CgA, and SIgA in saliva is suggested to be useful for the diagnosis of xerostomia and also to reveal disease status.


Asunto(s)
Saliva/química , Síndrome de Sjögren/diagnóstico , Xerostomía/diagnóstico , Adulto , Anciano , Citocinas/análisis , Citocinas/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Glándulas Salivales Menores/química , Glándulas Salivales Menores/metabolismo , Tasa de Secreción
7.
Oral Dis ; 21(2): 257-62, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24844187

RESUMEN

OBJECTIVES: Küttner tumour (KT), so-called chronic sclerosing sialoadenitis, is characterised by concomitant swelling of the submandibular glands secondary to strong lymphocytic infiltration and fibrosis independent of sialolith formation. However, recent studies have indicated that some patients with KT develop high serum levels of IgG4 and infiltration of IgG4-positive plasma cells, namely IgG4-related dacryoadenitis and sialoadenitis (IgG4-DS), so-called Mikulicz's disease. The aim of this study was to clarify the clinical and pathological associations between KT and IgG4-DS. MATERIALS AND METHODS: Fifty-four patients pathologically diagnosed with KT or chronic sialoadenitis were divided into two groups according to the presence or absence of sialolith (KT-S (+) or KT-S (-), respectively). RESULTS: There were no significant differences in the clinical findings, including the mean age, sex and disease duration, between the two groups. All patients in the KT-S (+) group showed unilateral swelling without infiltration of IgG4-positive plasma cells or a history of other IgG4-related diseases (IgG4-RD), while those in the KT-S (-) group showed bilateral swelling (37.5%), strong infiltration of IgG4-positive plasma cells (87.5%) and a history of other IgG4-RD (12.5%). CONCLUSIONS: These results suggest an association between the pathogeneses of KT-S (-) and IgG4-DS, but not KT-S (+).


Asunto(s)
Dacriocistitis/inmunología , Dacriocistitis/patología , Inmunoglobulina G/inmunología , Sialadenitis/inmunología , Sialadenitis/patología , Tuberculosis Bucal/inmunología , Adulto , Anciano , Dacriocistitis/sangre , Femenino , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Enfermedad de Mikulicz/inmunología , Enfermedad de Mikulicz/patología , Sialadenitis/sangre , Glándula Submandibular/patología , Tuberculosis Bucal/sangre
9.
J Oral Rehabil ; 42(3): 163-72, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25545582

RESUMEN

Influence of mandibular asymmetry and cross-bite on temporomandibular joint (TMJ) articulation remained unknown. This study aimed to investigate whether/how the working-side condylar movement irregularity and articular spaces during chewing differ between patients with mandibular asymmetry/cross-bite and control subjects. The cross-bite group and the control group consisted of 10 adult female patients and 10 adult female subjects, respectively. They performed unilateral gum-chewing. The mandibular movements were recorded using a video-based opto-electronic system. The 3D articular surface of the TMJ for each individual was reconstructed using CT/MRI data. For local condylar points, the normalised jerk cost (NJC) towards normal direction to the condylar surface, the angle between tangential velocity vector and condylar long axis and intra-articular space were measured. Three rotatory angles at centre of the condyle were also measured. During closing and intercuspation, (i) movements of posterior portion of the deviated side condyle showed significantly less smoothness as compared with those for the non-deviated side and control subjects, (ii) the rotations of the condyle on the deviated side induced greater intra-articular space at posterior and lateral portions. These findings suggest that chewing on the side of mandibular deviation/cross-bite may cause irregular movement and enlarged intra-articular space at posterior portion of the deviated side condyle.


Asunto(s)
Maloclusión/fisiopatología , Cóndilo Mandibular/fisiopatología , Masticación/fisiología , Movimiento/fisiología , Articulación Temporomandibular/fisiopatología , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Rango del Movimiento Articular/fisiología , Tomografía Computarizada por Rayos X , Grabación en Video , Adulto Joven
10.
J Oral Rehabil ; 42(1): 10-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25159131

RESUMEN

Response of temporomandibular joint (TMJ) articulation adapting to occlusal alteration has been sparsely known. For 10 healthy adults with acceptably good occlusion, an artificial occlusal interference (OI) was introduced to the lower molar on the balancing side of unilateral chewing. Subjects were asked to chew a gum on their preferred side. The chewing jaw movements with/without the OI were recorded using a video-based optoelectronic system. The mandibular movements were generated in each individual's TMJ model reconstructed by magnetic resonance images. The smoothness of local condylar point movements towards the normal direction of the condylar surface and interarticular space on the working side was measured. Overall, the smoothness of condylar point movements in the closing phase was impaired immediately after introduction of the OI. In the intercuspal phase, the OI increased the joint space. After about 60 chewing cycles, the movement smoothness and joint space began to recover. These findings suggest that OI on the balancing side induced irregular stress field translation on the working-side condylar surface followed by acute recovery process.


Asunto(s)
Cóndilo Mandibular/fisiopatología , Masticación/fisiología , Rango del Movimiento Articular/fisiología , Articulación Temporomandibular/fisiopatología , Adulto , Goma de Mascar , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Grabación en Video , Adulto Joven
11.
Opt Express ; 22(9): 11061-9, 2014 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-24921804

RESUMEN

The enhancement of light-matter coupling when light is confined to wavelength scale volumes is useful both for studying small sample volumes and increasing the overall sensing ability. At these length scales, nonradiative interactions are of key interest to which near-field optical techniques may reveal new phenomena facilitating next-generation material functionalities and applications. Efforts to develop novel chemical or biological sensors using metamaterials have yielded innovative ideas in the optical and terahertz frequency range whereby the spatially integrated response over a resonator structure is monitored via the re-radiated or leaked light. But although terahertz waves generally exhibit distinctive response in chemical molecules or biological tissue, there is little absorption for subwavelength size sample and therefore poor image contrast. Here, we introduce a method that spatially resolves the differential near-field phase response of the entire resonator as a spectral fingerprint. By simultaneously probing two metallic ring resonators, where one loaded with the sample of interest, the differential phase response is able to resolve the presence of guest molecules (e.g. methanol) as they are adsorbed or released within the pores of a prototypical porous coordination polymer.

12.
Phys Rev Lett ; 113(10): 107202, 2014 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-25238381

RESUMEN

Low-energy magnon excitations in multiferroic BiFeO3 were measured in detail as a function of temperature around several Brillouin zone centers by inelastic neutron scattering experiments on single crystals. Unique features around 1 meV are directly associated with the interplay of the Dzyaloshinskii-Moriya interaction and a small single-ion anisotropy. The temperature dependence of these and the exchange interactions were determined by fitting the measured magnon dispersion with spin-wave calculations. The spectra best fit an easy-axis type magnetic anisotropy and the deduced exchange and anisotropy parameters enable us to determine the anharmonicity of the magnetic cycloid. We then draw a direct connection between the changes in the parameters of spin Hamiltonian with temperature and the physical properties and structural deformations of BiFeO3.

13.
Am J Transplant ; 13(8): 2035-43, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23841834

RESUMEN

Posttransplant lymphoproliferative disorder (PTLD) continues to be a devastating and potentially life-threatening complication in organ transplant recipients. PTLD is associated with EBV infection and can result in malignant B cell lymphomas. Here we demonstrate that the PI3K/Akt/mTOR pathway is highly activated in EBV+ B cell lymphoma lines derived from patients with PTLD. Treatment with the mTORC1 inhibitor Rapamycin (RAPA) partially inhibited the proliferation of EBV+ B cell lines. Resistance to RAPA treatment correlated with high levels of Akt phosphorylation. An mTORC1/2 inhibitor and a PI3K/mTOR dual inhibitor suppressed Akt phosphorylation and showed a greater anti-proliferative effect on EBV+ B lymphoma lines compared to RAPA. EBV+ B cell lymphoma lines expressed high levels of PI3Kδ. We demonstrate that PI3Kδ is responsible for Akt activation in EBV+ B cell lymphomas, and that selective inhibition of PI3Kδ by either siRNA, or a small molecule inhibitor, augmented the anti-proliferative effect of RAPA on EBV+ B cell lymphomas. These results suggest that PI3Kδ is a novel, potential therapeutic target for the treatment of EBV-associated PTLD and that combined blockade of PI3Kδ and mTOR provides increased efficacy in inhibiting proliferation of EBV+ B cell lymphomas.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Imidazoles/farmacología , Linfoma de Células B/tratamiento farmacológico , Trastornos Linfoproliferativos/complicaciones , Inhibidores de las Quinasa Fosfoinosítidos-3 , Quinolinas/farmacología , Sirolimus/farmacología , Western Blotting , Línea Celular Tumoral , Sinergismo Farmacológico , Infecciones por Virus de Epstein-Barr/etiología , Infecciones por Virus de Epstein-Barr/patología , Herpesvirus Humano 4/efectos de los fármacos , Humanos , Linfoma de Células B/etiología , Linfoma de Células B/patología , Trastornos Linfoproliferativos/patología , Diana Mecanicista del Complejo 1 de la Rapamicina , Diana Mecanicista del Complejo 2 de la Rapamicina , Complejos Multiproteicos/antagonistas & inhibidores , Complejos Multiproteicos/metabolismo , Trasplante de Órganos/efectos adversos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Complicaciones Posoperatorias , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/metabolismo
14.
Clin Exp Immunol ; 167(2): 269-74, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22236003

RESUMEN

The activation of nuclear factor-kappa B (NF-κB) in vascular endothelial cells may be involved in vascular pathogeneses such as vasculitis or atherosclerosis. Recently, it has been reported that some amino acids exhibit anti-inflammatory effects. We investigated the inhibitory effects of a panel of amino acids on cytokine production or expression of adhesion molecules that are involved in inflammatory diseases in various cell types. The activation of NF-κB was determined in human coronary arterial endothelial cells (HCAECs) because NF-κB modulates the production of many cytokines and the expression of adhesion molecules. We examined the inhibitory effects of the amino acids cysteine, histidine and glycine on the induction of NF-κB activation, expression of CD62E (E-selectin) and the production of interleukin (IL)-6 in HCAECs stimulated with tumour necrosis factor (TNF)-α. Cysteine, histidine and glycine significantly reduced NF-κB activation and inhibitor κBα (IκBα) degradation in HCAECs stimulated with TNF-α. Additionally, all the amino acids inhibited the expression of E-selectin and the production of IL-6 in HCAECs, and the effects of cysteine were the most significant. Our results show that glycine, histidine and cysteine can inhibit NF-κB activation, IκBα degradation, CD62E expression and IL-6 production in HCAECs, suggesting that these amino acids may exhibit anti-inflammatory effects during endothelial inflammation.


Asunto(s)
Antiinflamatorios/farmacología , Arteritis/prevención & control , Vasos Coronarios/citología , Cisteína/farmacología , Células Endoteliales/efectos de los fármacos , Glicina/farmacología , Histidina/farmacología , Células Cultivadas/efectos de los fármacos , Células Cultivadas/metabolismo , Evaluación Preclínica de Medicamentos , Selectina E/biosíntesis , Selectina E/genética , Células Endoteliales/metabolismo , Endotelio Vascular/citología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Proteínas I-kappa B/metabolismo , Interleucina-6/biosíntesis , Interleucina-6/genética , Inhibidor NF-kappaB alfa , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/farmacología
15.
Phys Rev Lett ; 109(15): 157001, 2012 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-23102353

RESUMEN

We report on an (75)As-NMR study on the Fe-pnictide high-T(c) superconductor Y(0.95)La(0.05)FeAsO(1-y) (Y(0.95)La(0.05)1111) with T(c)=50 K that includes no magnetic rare-earth elements. The measurement of the nuclear-spin lattice-relaxation rate (75)(1/T(1)) has revealed that the nodeless bulk superconductivity takes place at T(c)=50 K while antiferromagnetic spin fluctuations develop moderately in the normal state. These features are consistently described by the multiple fully gapped s(±)-wave model based on the Fermi-surface nesting. Incorporating the theory based on band calculations, we propose that the reason that T(c)=50 K in Y(0.95)La(0.05)1111 is larger than T(c)=28 K in La1111 is that the Fermi-surface multiplicity is maximized, and hence the Fermi-surface nesting condition is better than that in La1111.

16.
Phys Rev Lett ; 108(7): 077202, 2012 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-22401246

RESUMEN

Using the inelastic neutron scattering technique, we measured the spin wave dispersion over the entire Brillouin zone of room temperature multiferroic BiFeO(3) single crystals with magnetic excitations extending to as high as 72.5 meV. The full spin waves can be explained by a simple Heisenberg Hamiltonian with a nearest-neighbor exchange interaction (J=4.38 meV), a next-nearest-neighbor exchange interaction (J'=0.15 meV), and a Dzyaloshinskii-Moriya-like term (D=0.107 meV). This simple Hamiltonian determined, for the first time, for BiFeO(3) provides a fundamental ingredient for understanding the novel magnetic properties of BiFeO(3).

19.
Eur J Gynaecol Oncol ; 33(2): 223-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22611970

RESUMEN

Malignant mixed Müllerian tumor (MMMT) of the female genital tract is uncommon and extremely rare in the Fallopian tube. We describe a case of primary MMMT of the Fallopian tube with carcinomatous and heterologous mesenchymal components in a 60-year-old woman. The patient underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, infracolic omentectomy, pelvic and paraaortic lymph node dissection, and resection of intrapelvic metastases. The tumor formed a large polypoid mass within the right Fallopian tube and had penetrated the wall to the paraovarian space. Microscopic examination revealed two components of poorly differentiated adenocarcinoma and high-grade sarcoma with chondromatous differentiation. The patient received six courses of adjuvant chemotherapy with ifomide and cisplatin and is currently in remission. Although MMMT in the Fallopian tube shows poor prognosis, primary cytoreductive surgery with platinum-based combination chemotherapy may improve survival.


Asunto(s)
Neoplasias de las Trompas Uterinas/patología , Neoplasias de las Trompas Uterinas/cirugía , Tumor Mulleriano Mixto/patología , Tumor Mulleriano Mixto/cirugía , Quimioterapia Adyuvante , Neoplasias de las Trompas Uterinas/tratamiento farmacológico , Femenino , Humanos , Histerectomía , Escisión del Ganglio Linfático , Persona de Mediana Edad , Tumor Mulleriano Mixto/tratamiento farmacológico , Tumor Mulleriano Mixto/secundario , Metástasis de la Neoplasia , Ovariectomía , Salpingectomía
20.
J Viral Hepat ; 18(6): 408-14, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20487261

RESUMEN

The immune modulator capacity of antigen-pulsed dendritic cells (DC) has been documented in patients with cancers and in animal models of chronic viral infections. Cancer antigen-pulsed DC are now used for treating patients with cancer. But viral antigen-pulsed DC are not used in chronic viral-infected patients because safety of antigen-pulsed DC has not been evaluated in these patients. DC were isolated from human peripheral blood mononuclear cells by culturing with human-grade granulocyte-macrophage colony stimulating factor and interleukin-4. Human blood DC were cultured with hepatitis B surface antigen (HBsAg) for 8h to prepare HBsAg-pulsed DC. After immunogenicity assessment of HBsAg-pulsed DC in vitro, five million HBsAg-pulsed DC were administered intradermally to five patients with chronic hepatitis B (CHB) 1-3 times. HBsAg-pulsed DC were immunogenic in nature because they produced significantly higher levels of interleukin-12 and interferon-γ compared to unpulsed DC (P<0.05). Also, HBsAg-pulsed DC induced proliferation of HBsAg-specific T lymphocytes in vitro. CHB patients injected with HBsAg-pulsed DC did not exhibit generalized inflammation, exacerbation of liver damage, abnormal kidney function, or features of autoimmunity. Administration of HBsAg-pulsed DC induced anti-HBs in two patients and HBsAg-specific cellular immunity in 1 patient. This is the first study about preparation of antigen-pulsed DC using human consumable materials for treating patients with CHB. Because HBsAg-pulsed DC were safe for all patients with CHB and had immune modulation capacity in some patients, phase I and phase II clinical trials with antigen-pulsed DC in CHB and other chronic infections are warranted.


Asunto(s)
Células Dendríticas/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Vacunas contra Hepatitis B/administración & dosificación , Hepatitis B Crónica/prevención & control , Adulto , Alanina Transaminasa/sangre , Nitrógeno de la Urea Sanguínea , ADN Viral/análisis , Femenino , Antígenos de Superficie de la Hepatitis B/administración & dosificación , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/terapia , Humanos , Inmunidad Celular , Inmunoterapia , Interferón gamma/inmunología , Interleucina-12/inmunología , Masculino , Persona de Mediana Edad , Proyectos Piloto
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