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1.
J Dent Res ; 103(3): 308-317, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38234039

RESUMEN

Neural crest cells (NCC) arise from the dorsal margin of the neural plate border and comprise a unique cell population that migrates to and creates the craniofacial region. Although factors including Shh, Fgf8, and bone morphogenetic proteins have been shown to regulate these biological events, the role of parathyroid hormone 1 receptor (Pth1r) has been less studied. We generated an NCC-specific mouse model for Pth1r and researched gene expression, function, and interaction focusing on nasal cartilage framework and midfacial development. Wnt1-Cre;Pth1rfl/fl;Tomatofl/+ mice had perinatal lethality, but we observed short snout and jaws, tongue protrusion, reduced NCC-derived cranial length, increased mineralization in nasal septum and hyoid bones, and less bone mineralization at interfrontal suture in mutants at E18.5. Importantly, the mutant nasal septum and turbinate cartilage histologically revealed gradual, premature accelerated hypertrophic differentiation. We then studied the underlying molecular mechanisms by performing RNA seq analysis and unexpectedly found that expression of Ihh and related signaling molecules was enhanced in mutant nasomaxillary tissues. To see if Pth1r and Ihh signaling are associated, we generated a Wnt1-Cre; Ihhfl/fl;Pth1rfl/fl;Tomatofl/+ (DKO) mouse and compared the phenotypes to those of each single knockout mouse: Wnt1-Cre; Ihhfl/fl;Pth1rfl/+;Tomatofl/+ (Ihh-CKO) and Wnt1-Cre;Ihhfl/+;Pth1rfl/fl;Tomatofl/+ (Pth1r-CKO). Ihh-CKO mice displayed a milder effect. Of note, the excessive hypertrophic conversion of the nasal cartilage framework observed in Pth1r-CKO was somewhat rescued DKO embryos. Further, a half cAMP responsive element and the 4 similar sequences containing 2 mismatches were identified from the promoter to the first intron in Ihh gene. Gli1-CreERT2;Pth1rfl/fl;Tomatofl/+, a Pth1r-deficient model targeted in hedgehog responsive cells, demonstrated the enlarged hypertrophic layer and significantly more Tomato-positive chondrocytes accumulated in the nasal septum and ethmoidal endochondral ossification. Collectively, the data suggest a relevant Pth1r/Ihh interaction. Our findings obtained from novel mouse models for Pth1r signaling illuminate previously unknown aspects in craniofacial biology and development.


Asunto(s)
Cartílagos Nasales , Cresta Neural , Receptor de Hormona Paratiroídea Tipo 1 , Animales , Ratones , Diferenciación Celular , Condrocitos/metabolismo , Proteínas Hedgehog/metabolismo , Ratones Noqueados , Cartílagos Nasales/metabolismo , Cráneo , Receptor de Hormona Paratiroídea Tipo 1/metabolismo
2.
J Dent Res ; 102(11): 1241-1251, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37575041

RESUMEN

Cranial base synchondroses are the endochondral ossification centers for cranial base growth and thus indispensable for proper skull, brain, and midfacial development. The synchondroses are composed of mirror-image growth plates that are continuously maintained from the embryonic to postnatal stage through chondrocyte differentiation. Several factors, including Pth1r signaling, are known to control fetal synchondrosis development. However, there are currently no reports regarding any role for Pth1r signaling in postnatal cranial base and synchondrosis development. Also, the mesenchymal cells that source Pth1r signaling for synchondroses are not known. Here, we employed an inducible mouse model, a hedgehog-responsive Gli1-CreERT2 driver, focusing on the postnatal study. We performed 2 inducible protocols using Gli1-CreERT2;Tomatofl/+ mice that uncovered distinct patterning of Gli1-positive and Gli1-negative chondrocytes in the synchondrosis cartilage. Moreover, we generated Gli1-CreERT2;Pth1rfl/fl;Tomatofl/+ mice to assess their functions in postnatal synchondrosis and found that the mutants had survived postnatally. The mutant skulls morphologically presented unambiguous phenotypes where we noticed the shortened cranial base and premature synchondrosis closure. Histologically, gradual disorganization in mutant synchondroses caused an uncommon remaining central zone between hypertrophic zones on both sides while the successive differentiation of round, flat, and hypertrophic chondrocytes was observed in control sections. These mutant synchondroses disappeared and were finally replaced by bone. Of note, the mutant fusing synchondroses lost their characteristic patterning of Gli1-positive and Gli1-negative chondrocytes, suggesting that loss of Pth1r signaling alters the distribution of hedgehog-responsive chondrocytes. Moreover, we performed laser microdissection and RNA sequencing to characterize the flat proliferative and round resting chondrocytes where we found flat chondrocytes have a characteristic feature of both chondrocyte proliferation and maturation. Taken together, these data demonstrate that Pth1r signaling in Gli1-positive cells is essential for postnatal development and maintenance in cranial base synchondroses. Our findings will elucidate previously unknown aspects of Pth1r functions in cranial biology and development.


Asunto(s)
Erizos , Base del Cráneo , Ratones , Animales , Proteína con Dedos de Zinc GLI1 , Cartílago , Condrocitos , Osteogénesis/genética
3.
J Phys Condens Matter ; 33(3)2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-33017809

RESUMEN

Positronium formation at 4H SiC(0001) surfaces were investigated upon the removal of natural oxide layers by hydrofluoric acid etching and heat treatment at 1000 K in ultra-high vacuum. Two types of positronium were observed in the positronium time-of-flight (PsTOF) measurements irrespective of conduction type and surface polarity. One type formed the major part of the PsTOF spectrum with a maximum energy of 4.7 ± 0.3 eV. This energy exceeded the theoretical value calculated with valence electrons. The PsTOF spectrum shape was different from those of metal surfaces, suggesting that the surface state electrons or conduction electrons need to be considered as the positronium source. Another positronium appeared at 1000 K in the tail of the PsTOF spectrum with a maximum energy of 0.2-0.5 eV. This thermally-assisted athermal positronium may be formed via the surface state positrons and electrons.

4.
Transplant Proc ; 50(8): 2562-2564, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30173850

RESUMEN

We report a case of living related renal transplantation that used the recipient's saphenous vein as a graft to extend the length of the right donor renal vein. A 41-year-old woman underwent ABO-incompatible living related renal transplantation from her 74-year-old mother in November 2014. A retroperitoneal laparoscopic right donor nephrectomy was performed, because the right kidney showed a cyst on preoperative computed tomography. As the right kidney after donor nephrectomy had a short renal vein and the kidney was large at 280 g, anastomosis with the external iliac vein was difficult. Therefore, we obtained the recipient's 15-cm-long right saphenous vein and created a 1 cm saphenous vein graft. We anastomosed 1 side of the saphenous vein graft to the allograft renal vein in bench surgery and performed end-to-side anastomosis of the other end to the recipient's external iliac vein. The allograft renal artery was used to perform end-to-end anastomosis to the recipient's internal iliac artery. Allograft kidney function was good after transplantation. When the longer axis of the renal graft vein is short, as in the right kidney, a saphenous vein graft may be useful.


Asunto(s)
Trasplante de Riñón/métodos , Donadores Vivos , Nefrectomía/métodos , Venas Renales/trasplante , Vena Safena/trasplante , Adulto , Anastomosis Quirúrgica , Femenino , Humanos , Riñón/cirugía , Recolección de Tejidos y Órganos/métodos
5.
Br J Oral Maxillofac Surg ; 56(8): 732-738, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30131193

RESUMEN

Cathepsin K inhibitors are new drugs with the potential for the treatment of osteoporosis because they sustain bony remodelling better than bone resorption inhibitors such as bisphosphonates. The treatment of osteoporosis with inhibitors of bony resorption is associated with osteonecrosis of the jaw, as the deterioration in bony quality that they induce is thought to be one of its causes. The quality of bone is delineated by structural and material characteristics (which include the degree and quality of mineralisation, and depends on the content of proteoglycan and the structural integrity of the bony collagen).1,2 Animal and clinical studies have shown that cathepsin K inhibitors improve the mineral density and structural characteristics of bone, but their effect on the rest remains unknown. We therefore hypothesised that these inhibitors will affect the material characteristics of newly-formed mandibular bone. To verify our hypothesis, we used Raman microspectroscopy to examine such bone in rats that were given a cathepsin K inhibitor, and found unusual crystallinity and an increased substitution of carbonate (CO32-) in its crystal structure.


Asunto(s)
Compuestos de Bifenilo/farmacología , Densidad Ósea/efectos de los fármacos , Catepsina K/antagonistas & inhibidores , Mandíbula/efectos de los fármacos , Animales , Femenino , Mandíbula/diagnóstico por imagen , Ratas , Ratas Wistar , Tomografía Computarizada por Rayos X
6.
Int J Oral Maxillofac Surg ; 47(9): 1206-1213, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29550280

RESUMEN

Bone quality is defined by structural and material characteristics. Most studies on the mandible have focused on the analysis of structural characteristics, with insufficient investigation of material characteristics. This study tested whether zoledronate affects the material characteristics of newly formed mandibular bone. Thirty-six female Wistar rats were assigned to three groups: sham-ovariectomized rats (SHAM, n=12), ovariectomized rats (OVX, n=12), and ovariectomized rats treated with zoledronate (ZOL, n=12). The left side of the mandibular ramus of all rats was drilled bicortically. Twenty-eight days after surgery, all surviving rats were euthanized and all mandibles were removed. Raman microspectroscopy was performed, and five spectra per specimen of newly formed mandibular bone were analysed. Compared with OVX rats, the mineral/matrix ratio in ZOL rats was significantly increased (5.43±1.88 vs. 7.86±2.05), while crystallinity (0.055±0.002 vs. 0.050±0.002), relative proteoglycan content (0.43±0.10 vs. 0.31±0.05), and collagen structural integrity (1.16±0.21 vs. 0.72±0.06) were significantly decreased. These changes in material characteristics may explain why rats that received zoledronate exhibited peculiar biological phenomena such as bisphosphonate-related osteonecrosis of the jaw.


Asunto(s)
Conservadores de la Densidad Ósea/farmacología , Mandíbula/efectos de los fármacos , Mandíbula/ultraestructura , Ácido Zoledrónico/farmacología , Animales , Biomarcadores/análisis , Densidad Ósea/efectos de los fármacos , Femenino , Fémur/diagnóstico por imagen , Fémur/efectos de los fármacos , Imagenología Tridimensional , Mandíbula/diagnóstico por imagen , Ovariectomía , Ratas , Ratas Wistar , Espectrometría Raman , Microtomografía por Rayos X
8.
J Phys Condens Matter ; 28(47): 475002, 2016 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-27662111

RESUMEN

We have measured the time-of-flight of ortho-positronium emitted from Cs-, Na- and Li-coated single-crystal tungsten surfaces. The data obtained after the coating show a new positronium energy component with a specific energy loss in addition to the component whose emission energy is simply determined by the positron and the electron work functions. We suggest that this new component is attributed to the formation of positronium accompanied by inter-band transition and/or surface plasmon excitation at the surfaces.

9.
Drug Res (Stuttg) ; 66(2): 74-81, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26158794

RESUMEN

OBJECTIVE: Tofogliflozin is an oral hypoglycemic agent with a novel mechanism of action that reduces blood glucose levels by promoting glucose excretion in urine, achieved by selectively inhibiting sodium-glucose co-transporter 2 (SGLT2). We evaluated the effects of several selected anti-type 2 diabetes mellitus (T2DM) drugs-glimepiride, metformin, sitagliptin, pioglitazone, miglitol, nateglinide, and voglibose-on the pharmacokinetics and pharmacodynamics of tofogliflozin, and the effects of tofogliflozin on the pharmacokinetics of these anti-T2DM drugs in healthy male volunteers. METHODS: A single dose of either tofogliflozin alone, one of the anti-T2DM drugs alone, or co-administration of tofogliflozin and the anti-T2DM drug was administered to 108 healthy men. Cmax, AUCinf, and cumulative urine glucose excretion after co-administration of tofogliflozin and each of the anti-T2DM drugs was evaluated relative to the values of those parameters after administration of each drug alone. RESULTS: None of the anti-T2DM drugs had any effect on tofogliflozin exposure. Tofogliflozin had no or little effect on the exposure of any anti-T2DM drug. No anti-T2DM drug had any major effect on the cumulative urine glucose excretion induced by tofogliflozin. There were no safety concerns evident after administration of any drug alone or in co-administration. CONCLUSIONS: Neither the pharmacokinetics nor the pharmacodynamics of tofogliflozin was affected by any of the anti-T2DM drugs evaluated in this study, nor was the pharmacokinetics of any of the anti-T2DM drugs affected by tofogliflozin in healthy male volunteers.


Asunto(s)
Compuestos de Bencidrilo/farmacología , Compuestos de Bencidrilo/farmacocinética , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucósidos/farmacología , Glucósidos/farmacocinética , Hipoglucemiantes/farmacología , Hipoglucemiantes/farmacocinética , Inhibidores del Cotransportador de Sodio-Glucosa 2 , 1-Desoxinojirimicina/análogos & derivados , 1-Desoxinojirimicina/farmacocinética , 1-Desoxinojirimicina/farmacología , Adulto , Ciclohexanos/farmacocinética , Ciclohexanos/farmacología , Diabetes Mellitus Tipo 2/sangre , Interacciones Farmacológicas , Glucosa/análisis , Voluntarios Sanos , Humanos , Inositol/análogos & derivados , Inositol/farmacocinética , Inositol/farmacología , Masculino , Metformina/farmacocinética , Metformina/farmacología , Persona de Mediana Edad , Nateglinida , Fenilalanina/análogos & derivados , Fenilalanina/farmacocinética , Fenilalanina/farmacología , Pioglitazona , Fosfato de Sitagliptina/farmacocinética , Fosfato de Sitagliptina/farmacología , Compuestos de Sulfonilurea/farmacocinética , Compuestos de Sulfonilurea/farmacología , Tiazolidinedionas/farmacocinética , Tiazolidinedionas/farmacología , Orina/química , Adulto Joven
10.
Blood Cancer J ; 5: e373, 2015 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-26636288

RESUMEN

Bortezomib (BTZ), a proteasome inhibitor, is widely used in the treatment of multiple myeloma (MM), but a fraction of patients respond poorly to this agent. To identify factors predicting the duration of progression-free survival (PFS) of MM patients on BTZ treatment, the expression of proteasome and endoplasmic reticulum (ER) stress-related genes was quantified in primary samples from patients receiving a combination of BTZ and dexamethasone (BD). Fifty-six MM patients were stratified into a group with PFS<6 months (n=33) and a second group with PFS⩾6 months (n=23). Of the 15 genes analyzed, the expression of activating transcription factor 3 (ATF3) and ATF4 was significantly lower in patients with shorter PFS (P=0.0157 and P=0.0085, respectively). Chromatin immunoprecipitation analysis showed that these ATFs bind each other and transactivate genes encoding the pro-apoptotic transcription factors, CHOP and Noxa, which promote ER stress-associated apoptosis. When either ATF3 or ATF4 expression was silenced, MM cells partially lost sensitivity to BTZ treatment. This was accompanied by lower levels of Noxa, CHOP and DR5. Thus low basal expression of ATF3 and ATF4 may attenuate BTZ-induced apoptosis. Hence, ATF3 and ATF4 could potentially be used as biomarkers to predict efficacy of BD therapy in patients with MM.


Asunto(s)
Factor de Transcripción Activador 3/metabolismo , Factor de Transcripción Activador 4/metabolismo , Bortezomib/uso terapéutico , Dexametasona/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Apoptosis , Biomarcadores , Línea Celular Tumoral , Supervivencia sin Enfermedad , Quimioterapia Combinada , Humanos , Proteínas Proto-Oncogénicas c-bcl-2/genética , ARN Mensajero/genética , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo
12.
Am J Transplant ; 15(2): 333-45, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25582188

RESUMEN

Acute and chronic rejection impact distinct compartments of cardiac allografts. Intramyocardial mononuclear cell infiltrates define acute rejection, whereas chronic rejection affects large arteries. Hearts transplanted from male to female C57BL/6 mice undergo acute rejection with interstitial infiltrates at 2 weeks that resolve by 6 weeks when large arteries develop arteriopathy. These processes are dependent on T cells because no infiltrates developed in T cell-deficient mice and transfer of CD4 T cells restored T cell as well as macrophage infiltrates and ultimately neointima formation. Markers of inflammatory macrophages were up-regulated in the interstitium acutely and decreased as markers of wound healing macrophages increased chronically. Programmed cell death protein, a negative costimulator, and its ligand PDL1 were up-regulated in the interstitium during resolution of acute rejection. Blocking PDL1:PD1 interactions in the acute phase increased interstitial T cell infiltrates. Toll-like receptor (TLR) 4 and its endogenous ligand hyaluronan were increased in arteries with neointimal expansion. Injection of hyaluronan fragments increased intragraft production of chemokines. Our data indicate that negative costimulatory pathways are critical for the resolution of acute interstitial infiltrates. In the arterial compartment recognition of endogenous ligands including hyaluronan by the innate TLRs may support the progression of arteriopathy.


Asunto(s)
Rechazo de Injerto/fisiopatología , Trasplante de Corazón , Miocardio/metabolismo , Miocardio/patología , Transducción de Señal/fisiología , Animales , Antígeno B7-H1/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Quimiocina CCL2/metabolismo , Quimiocina CXCL9/metabolismo , Femenino , Ácido Hialurónico/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Animales , Receptor Toll-Like 4/metabolismo
13.
J Clin Pharm Ther ; 40(2): 232-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25402940

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: This study aimed to elucidate the pharmacokinetics of erlotinib in Japanese patients with advanced non-small cell lung cancer (NSCLC) and to investigate the relationship between erlotinib exposure and the occurrence of interstitial lung disease (ILD)-like events. METHODS: Population pharmacokinetics analysis was performed using nonlinear mixed-effects modelling software (NONMEM) based on 348 plasma samples from 97 patients obtained in two phase II clinical studies. Individual empirical Bayesian estimates (EBEs) of apparent oral clearance (CL/F) and Cmax were compared between the patients who developed and did not develop ILD-like events. RESULTS: A 1-compartment model with first-order absorption and first-order elimination was used to describe the plasma concentrations of erlotinib. The estimated population pharmacokinetics parameters were as follows: 4·71 L/h for CL/F, 163 L for apparent volume of distribution (Vc /F) and 1·97 h(-1) for absorption rate constant (Ka ). Total bilirubin (TBIL) and alpha 1-acid glycoprotein (AGP) were identified as statistically significant covariates for CL/F. No differences in CL/F and Cmax were observed between the patients with ILD-like events and those without ILD-like events. WHAT IS NEW AND CONCLUSIONS: A population pharmacokinetics model of erlotinib was developed and validated in Japanese patients. There was no relationship between exposure of erlotinib before the occurrence of ILD-like events and the occurrence of ILD-like events when erlotinib was administered at the same dosage. The high plasma concentration of erlotinib reported in patients after the onset of ILD-like events may be explained by CL/F decrease which occurs along with increasing levels of AGP which was identified as a covariate for CL/F.


Asunto(s)
Pueblo Asiatico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Clorhidrato de Erlotinib/farmacocinética , Modelos Biológicos , Inhibidores de Proteínas Quinasas/farmacocinética , Adulto , Anciano , Teorema de Bayes , Clorhidrato de Erlotinib/uso terapéutico , Femenino , Humanos , Japón , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/uso terapéutico
14.
J Vis ; 14(13): 14, 2014 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-25406159

RESUMEN

When distinguishing whether a face displays a certain emotion, some regions of the face may contain more useful information than others. Here we ask whether people differentially attend to distinct regions of a face when judging different emotions. Experiment 1 measured eye movements while participants discriminated between emotional (joy, anger, fear, sadness, shame, and disgust) and neutral facial expressions. Participant eye movements primarily fell in five distinct regions (eyes, upper nose, lower nose, upper lip, nasion). Distinct fixation patterns emerged for each emotion, such as a focus on the lips for joyful faces and a focus on the eyes for sad faces. These patterns were strongest for emotional faces but were still present when viewers sought evidence of emotion within neutral faces, indicating a goal-driven influence on eye-gaze patterns. Experiment 2 verified that these fixation patterns tended to reflect attention to the most diagnostic regions of the face for each emotion. Eye movements appear to follow both stimulus-driven and goal-driven perceptual strategies when decoding emotional information from a face.


Asunto(s)
Emociones/fisiología , Movimientos Oculares/fisiología , Expresión Facial , Reconocimiento Visual de Modelos/fisiología , Adulto , Atención/fisiología , Femenino , Fijación Ocular/fisiología , Humanos , Masculino , Adulto Joven
15.
Am J Transplant ; 14(8): 1753-64, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25040187

RESUMEN

The pathogenic role of macrophages in antibody-mediated rejection (AMR) remains unclear. Monocyte chemoattractant protein-1 (MCP-1/CCL2) is a potent chemotactic factor for monocytes and macrophages. The current studies used a murine model of AMR to investigate the role of graft-derived CCL2 in AMR and how macrophages may participate in antibody-mediated allograft injury. B6.CCR5−/−/CD8−/− recipients rejected MHC-mismatched WT A/J allografts with high donor-reactive antibody titers and diffuse C4d deposition in the large vessels and myocardial capillaries, features consistent with AMR. In contrast, A/J.CCL2−/− allografts induced low donor-reactive antibody titers and C4d deposition at Day 7 posttransplant. Decreased donor-reactive CD4 T cells producing interferon gamma were induced in response to A/J.CCL2−/− versus WT allografts. Consequently, A/J.CCL2−/− allograft survival was modestly but significantly longer than A/J allografts. Macrophages purified from WT allografts expressed high levels of IL-1ß and IL-12p40 and this expression and the numbers of classically activated macrophages were markedly reduced in CCL2-deficient allografts on Day 7. The results indicate that allograft-derived CCL2 plays an important role in directing classically activated macrophages into allografts during AMR and that macrophages are important contributors to the inflammatory environment mediating graft tissue injury in this pathology, suggesting CCL2 as a therapeutic target for AMR.


Asunto(s)
Anticuerpos/sangre , Quimiocina CCL2/metabolismo , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Trasplante de Corazón , Animales , Linfocitos T CD4-Positivos/citología , Proliferación Celular , Supervivencia Celular , Quimiocina CCL2/genética , Quimiotaxis , Citocinas/metabolismo , Citometría de Flujo , Supervivencia de Injerto , Interferón gamma/metabolismo , Macrófagos/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Monocitos/citología , Factores de Tiempo , Trasplante Homólogo
16.
J Oral Rehabil ; 41(10): 715-22, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24909970

RESUMEN

Experimental loss of occlusal support caused by the extraction or grinding of molar teeth has been reported to foment the impairment of learning and memory in laboratory animals. The purpose of this study was to examine the effect of occlusal reconstruction after long-term loss of molars on spatial memory by using 8-arm radial maze and by assessing histopathological changes of neuron density in the hippocampus. Experimental dentures were inserted into the oral cavities of molarless rats to recover the occlusal support. Age-matched groups of control, molarless and denture-wearing rats were trained to perform the maze tasks. The difference of the error incidence in the maze task was evaluated between three groups. The difference of neuron density between three groups was also evaluated at the end of the maze task. Serum corticosterone levels were also measured to estimate the chronic stress, which could be caused by extraction, insertion of the experimental denture or any experimental procedure. The error incidence in the denture-wearing group was significantly higher than that of the control group, but significantly lower than that of the molarless group. Significant differences of neuron density were observed between three groups in each of the hippocampal CA1, CA3 and DG subfields. No significant difference of the serum corticosterone levels between three groups could be observed. From the results of this study, it was suggested that the recovery of occlusal support would bring amelioration of cognitive impairment concomitant with long period loss of molars in rats.


Asunto(s)
Hipocampo/patología , Arcada Parcialmente Edéntula/rehabilitación , Neuronas/patología , Memoria Espacial/fisiología , Animales , Corticosterona/sangre , Masculino , Maxilar , Aprendizaje por Laberinto , Diente Molar , Ratas , Ratas Wistar , Estrés Psicológico/sangre , Resultado del Tratamiento
17.
Am J Transplant ; 14(3): 568-79, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24502272

RESUMEN

Differences in levels of environmentally induced memory T cells that cross-react with donor MHC molecules are postulated to account for the efficacy of allograft tolerance-inducing strategies in rodents versus their failure in nonhuman primates and human transplant patients. Strategies to study the impact of donor-reactive memory T cells on allografts in rodents have relied on the pretransplant induction of memory T cells cross-reactive with donor allogeneic MHC molecules through recipient viral infection, priming directly with donor antigen or adoptive transfer of donor antigen primed memory T cells. Each approach accelerates allograft rejection and confers resistance to tolerance induction, but also biases the T cell repertoire to strong donor reactivity. The ability of endogenous memory T cells within unprimed mice to directly reject an allograft is unknown. Here, we show a direct association between increased duration of cold ischemic allograft storage and numbers and enhanced functions of early graft infiltrating endogenous CD8 memory T cells. These T cells directly mediate rejection of allografts subjected to prolonged ischemia and this rejection is resistant to costimulatory blockade. These findings recapitulate the clinically significant impact of endogenous memory T cells with donor reactivity in a mouse transplant model in the absence of prior recipient priming.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Rechazo de Injerto/inmunología , Trasplante de Corazón/efectos adversos , Memoria Inmunológica/inmunología , Traslado Adoptivo , Aloinjertos , Animales , Anticuerpos Monoclonales/farmacología , Western Blotting , Isquemia Fría , Citocinas/genética , Citocinas/metabolismo , Citometría de Flujo , Humanos , Técnicas para Inmunoenzimas , Antígeno-1 Asociado a Función de Linfocito/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
18.
Blood Cancer J ; 3: e150, 2013 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-24096714

RESUMEN

The proteasome inhibitor bortezomib has revolutionized the treatment of multiple myeloma. However, bortezomib-induced peripheral neuropathy (BiPN) is a serious complication that compromises clinical outcome. If patients with a risk of developing BiPN could be predicted, physicians might prefer weekly, reduced-dose, or subcutaneous approaches. To seek biomarkers for BiPN, we conducted a multicenter prospective study using a simple and unique system. Multiple myeloma patients received twice-weekly or weekly 1.3 mg/m(2) bortezomib intravenously, and a 2-ml sample of whole blood was obtained before treatment and 2-3 days and 1-3 weeks after the first dose. Induction of gene expression was then quantified by real-time PCR. Of a total of 64 enrolled patients, 53 patient samples qualified for mRNA analysis. The BiPN grade was associated with phytohemagglutinin-induced IL2, IFNG and TNFSF2, as well as with lipopolysaccharide-induced IL6 levels. More importantly, of the 19 patients showing a 3-fold increase in phytohemagglutinin-induced IL2, 14 did not suffer from BiPN (73.7% prediction), whereas of the 34 patients with a <3-fold increase, 23 experienced BiPN (67.6% prediction). Therefore, we concluded that pretreatment of phytohemagglutinin-induced IL2 mRNA levels in whole blood serve as a promising biomarker for predicting BiPN, and this finding warrants validation in a larger study.

19.
Am J Transplant ; 13(9): 2293-307, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23914930

RESUMEN

Endogenous memory CD8 T cells infiltrate MHC-mismatched cardiac allografts within 12-24 h posttransplant in mice and are activated to proliferate and produce IFN-γ. To more accurately assess the graft injury directly imposed by these endogenous memory CD8 T cells, we took advantage of the ability of anti-LFA-1 mAb given to allograft recipients on days 3 and 4 posttransplant to inhibit the generation of primary effector T cells. When compared to grafts from IgG-treated recipients on day 7 posttransplant, allografts from anti-LFA-1 mAb-treated recipients had increased numbers of CD8 T cells but these grafts had marked decreases in expression levels of mRNA encoding effector mediators associated with graft injury and decreases in donor-reactive CD8 T cells producing IFN-γ. Despite this decreased activity within the allograft, CD8 T cells in allografts from recipients treated with anti-LFA-1 mAb continued to proliferate up to day 7 posttransplant and did not upregulate expression of the exhaustion marker LAG-3 but did have decreased expression of ICOS. These results indicate that endogenous memory CD8 T cells infiltrate and proliferate in cardiac allografts in mice but do not express sufficient levels of functions to mediate overt graft injury and acute rejection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Trasplante de Corazón , Inmunología del Trasplante , Aloinjertos , Animales , Anticuerpos Monoclonales/farmacología , Antígenos CD/biosíntesis , Linfocitos T CD4-Positivos/inmunología , Ligando de CD40/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Proteína Coestimuladora de Linfocitos T Inducibles/biosíntesis , Activación de Linfocitos , Ratones , Proteína del Gen 3 de Activación de Linfocitos
20.
Am J Transplant ; 13(9): 2268-79, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23834725

RESUMEN

Lymphopenia is induced by lymphoablative therapies and chronic viral infections. We assessed the impact of lymphopenia on cardiac allograft survival in recipients conditioned with peritransplant costimulatory blockade (CB) to promote long-term graft acceptance. After vascularized MHC-mismatched heterotopic heart grafts were stably accepted through CB, lymphopenia was induced on day 60 posttransplant by 6.5 Gy irradiation or by administration of anti-CD4 plus anti-CD8 mAb. Long-term surviving allografts were gradually rejected after lymphodepletion (MST = 74 ± 5 days postirradiation). Histological analyses indicated signs of severe rejection in allografts following lymphodepletion, including mononuclear cell infiltration and obliterative vasculopathy. Lymphodepletion of CB conditioned recipients induced increases in CD44(high) effector/memory T cells in lymphatic organs and strong recovery of donor-reactive T cell responses, indicating lymphopenia-induced proliferation (LIP) and donor alloimmune responses occurring in the host. T regulatory (CD4(+) Foxp(3+)) cell and B cell numbers as well as donor-specific antibody titers also increased during allograft rejection in CB conditioned recipients given lymphodepletion. These observations suggest that allograft rejection following partial lymphocyte depletion is mediated by LIP of donor-reactive memory T cells. As lymphopenia may cause unexpected rejection of stable allografts, adequate strategies must be developed to control T cell proliferation and differentiation during lymphopenia.


Asunto(s)
Rechazo de Injerto/inmunología , Trasplante de Corazón , Linfopenia/inmunología , Tolerancia Periférica/inmunología , Tolerancia al Trasplante/efectos de los fármacos , Traslado Adoptivo , Aloinjertos , Animales , Femenino , Linfopenia/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Linfocitos T , Irradiación Corporal Total
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