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AIM: In Japan, elementary schools are committed to early discovery of child abuse and neglect. Under Japanese law, dentists are required to be involved in child welfare and early detection of child abuse. However, the extent to which dental practitioners cooperate for prevention of child abuse with schools remains limited to date. Therefore, we undertook a community-based project that aimed to develop screening indicators to identify potentially abused children based on their oral health condition and behavioural characteristics in education settings. We have already reported on the relationship between oral health condition and child abuse. The present study established an indicator that can facilitate identification and prevention of child abuse/neglect. METHODS: Study design: Cross-sectional study. Questionnaires were given to teachers at an elementary school to ascertain behavioural characteristics observed in children who experienced abuse. CONCLUSION: We developed a check sheet for proper assessment, which requires as little effort as possible, and an index for screening children in need based on teaching staff's observation of students' daily behaviour in school settings. Highly selected items are advantageous as they lead to a decrease in non-response or responses, which can help in improving the accuracy of the response to each question.
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Maltrato a los Niños , Odontólogos , Niño , Humanos , Estudios Transversales , Rol Profesional , Maltrato a los Niños/diagnóstico , Instituciones AcadémicasRESUMEN
BACKGROUND: Heart rate variability (HRV) has proven to be a powerful non-invasive tool to investigate cardiac autonomic control and, seems to be influenced by nutritional status and exercise practice. However, the acute effects of fed or fasting states on HRV and blood pressure (BP) during low-to-moderate intensity aerobic exercise are currently unknown. Therefore, we investigated the baseline values and behavior of HRV, BP, and heart rate (HR) before and after low-to-moderate intensity aerobic exercise in fed and fasted states in healthy adults. METHODS: 12 healthy individuals with mean age (SD) 59.0 (9.1) years performed two tests on a treadmill at 80% of the mean velocity of the 6-min walking test separated by 48â¯h: 12â¯h fasted (FST) or 1â¯h fed (FED). HRV, BP and HR were analyzed at rest, posttest, and at the third, fifth, and seventh minutes of recovery. RESULTS: HRV and HR presented no significant alterations between nutritional conditions. HR at baseline was not different between nutritional conditions. Diastolic blood pressure was increased during the fasted baseline state. CONCLUSIONS: The results of the current study provide that 12â¯h overnight fasting does not seem to be enough to affect significant changes in the autonomic modulation in healthy adults submitted to low-to-moderate intensity aerobic exercise.
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In a cross-sectional study, visit-to-visit blood pressure (BP) variability was shown to be associated with artery remodelling. Here, we investigated the impact of visit-to-visit BP variability and average BP on the carotid artery remodelling progression in high-risk elderly according to different classes of antihypertension medication use/non-use. BP measurements and carotid ultrasound were performed in the common carotid artery in 164 subjects (mean age 79.7 years at baseline, 74.7% females) with one or more cardiovascular risk factors. Based on 12 visits (1 × /month for 1 year), we calculated visit-to-visit BP variability expressed as the standard deviation (s.d.), coefficient of variation (CV), maximum BP, minimum BP and delta (maximum-minimum) BP. We measured mean intima-media thickness (IMT) as well as stiffness parameter ß were measured at baseline and at the mean 4.2-year follow-up. In a multiple regression analysis, the maximum, minimum, s.d. and average of systolic BP (SBP) were significantly associated with a change in ß-values between the baseline and follow-up after adjustment for age, smoking, lower high-density lipoprotein level, baseline ß-value and follow-up period. There were no significant associations between the visit-to-visit BP variability measures and the change in mean IMT. Significant associations of maximum, minimum, s.d. and average SBP were found with increased ß-values in the subjects without calcium channel blocker (CCB) use and in the subjects using renin-angiotensin system inhibitors (RASIs). Thus, exaggerated visit-to-visit SBP variability and a high average SBP level were significant predictors of progression in carotid arterial stiffness in high-risk elderly without CCBs use and in those using a RASI.
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Antagonistas de Receptores de Angiotensina/farmacología , Presión Sanguínea , Bloqueadores de los Canales de Calcio/farmacología , Arteria Carótida Común/efectos de los fármacos , Rigidez Vascular , Anciano , Anciano de 80 o más Años , Antagonistas de Receptores de Angiotensina/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Arteria Carótida Común/diagnóstico por imagen , Grosor Intima-Media Carotídeo , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Estudios ProspectivosRESUMEN
Nicotinic acetylcholine receptor (nAChR) clustering is a key event in the synaptogenesis of the neuromuscular junction (NMJ) for the efficient transmission of neural signals from motor neurons to skeletal muscle. The microphthalmic mouse (mi/mi) with a mutation in the mitf gene cannot perform occlusion, because its teeth do not erupt. The present study attempted to elucidate the contribution of occlusion to the clustering of nAChR in the NMJ of the masseter, with mi/mi as a model system. In mice at 1 week of age, no significant change in the fragmentation or volume of the nAChR cluster was observed in either the masseter or gastrocnemius between breast-fed +/+ and mi/mi. In mice at 4 and 12 weeks of age, after the occlusion emerged in the +/+, excessive fragmentation and volume decline in the nAChR cluster were observed in the masseter of mi/mi fed a powdered diet compared with +/+ fed a pellet or powdered diet, whereas, in the gastrocnemius, no such differences were observed between the 2 strains. These results indicate abnormal formation of the nAChR cluster in the NMJ of the masseter of mi/mi, suggesting that occlusion is essential for the normal progress of nAChR clustering in the NMJ of the masseter.
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Fuerza de la Mordida , Oclusión Dental , Músculo Masetero/fisiología , Unión Neuromuscular/fisiología , Receptores Nicotínicos/fisiología , Animales , Membrana Celular/metabolismo , Retroalimentación Fisiológica , Estudios Longitudinales , Ratones , Ratones Mutantes , Microftalmía/genética , Contracción Muscular/fisiología , Músculo EsqueléticoRESUMEN
OBJECTIVE: To determine the function of platelet-derived growth factor (PDGF) in the final differentiation phase of tongue striated muscle cells. MATERIALS AND METHODS: We analyzed the expressions of PDGF-A, -B, platelet-derived growth factor receptor (PDGFR)-α, and PDGFR-ß in mouse tongues between embryonic days (E) 11 and 15. Furthermore, we examined the effects of human recombinant PDGF-AB and the peptide antagonist for PDGFRs using an organ culture system of mouse embryonic tongue. Mouse tongues at E12 were cultured in BGJb medium containing human recombinant PDGF-AB for 4 days or the peptide antagonist for PDGF receptors for 8 days. RESULTS: PDGF-A, -B, PDGFR-α, and -ß were expressed in the differentiating muscle cells between E11 and 15. The human recombinant PDGF-AB induced increases in the mRNA expressions of myogenin and muscle creatine kinase (MCK) and the number of fast myosin heavy chain (fMHC)-positive cells, markers for the differentiation of muscle cells. On the other hand, the peptide antagonist for PDGFRs induced suppressions in the mRNA expressions of myogenin and MCK, and the number of fMHC-positive cells. Both the PDGF-AB and the antagonist failed to affect the expressions of cell proliferation markers. CONCLUSION: These results suggest that PDGF functions as a positive regulator in the final differentiation phase of tongue muscle cells in mouse embryos.
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Células Musculares/citología , Músculo Esquelético/embriología , Factor de Crecimiento Derivado de Plaquetas/fisiología , Lengua/embriología , Animales , Diferenciación Celular/fisiología , Proliferación Celular , Forma MM de la Creatina-Quinasa/análisis , Edad Gestacional , Humanos , Ratones , Desarrollo de Músculos/fisiología , Miogenina/análisis , Cadenas Pesadas de Miosina/análisis , Técnicas de Cultivo de Órganos , Factor de Crecimiento Derivado de Plaquetas/análisis , Proteínas Proto-Oncogénicas c-sis/análisis , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/análisis , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/análisis , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Proteínas RecombinantesRESUMEN
OBJECTIVE: A new loop-mediated isothermal amplification (LAMP) test kit, including a simple DNA extraction device for the detection of Mycobacterium tuberculosis complex, was developed for commercial use and evaluated for its usefulness in diagnosing tuberculosis (TB). DESIGN: The LAMP test was performed using untreated and N-acetyl-L-cysteine (NALC) NaOH-treated sputum specimen. The efficiency of the kit was compared with other conventional laboratory examinations, including other nucleic acid amplification (NAA) tests. RESULTS: The sensitivity of LAMP using raw sputum (direct LAMP) in smear- and culture-positive specimens was 98.2% (95%CI 94.9-99.4), while the sensitivity in smear-negative, culture-positive specimens was 55.6% (95%CI 43.4-68.0). The diagnostic sensitivity of direct LAMP for the diagnosis of individuals with TB was 88.2% (95%CI 81.4-92.7). The sensitivity values of direct LAMP were slightly, but not statistically significantly lower than those of Cobas Amplicor MTB and TRC Rapid MTB, while the sensitivity of the LAMP test using NALC-NaOH treated sputum was significantly lower than other NAA tests (P < 0.05) for smear-negative, culture-positive specimens. The new commercial version of the LAMP kit was easy to handle and yielded results within 1 h of receiving sputum specimens. CONCLUSIONS: This test is considered a promising diagnostic tool for TB, even for peripheral laboratories with limited equipment, such as those in developing countries.
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Mycobacterium tuberculosis/aislamiento & purificación , Técnicas de Amplificación de Ácido Nucleico/métodos , Tuberculosis/diagnóstico , Acetilcisteína/química , ADN Bacteriano/análisis , Países en Desarrollo , Humanos , Mycobacterium tuberculosis/genética , Sensibilidad y Especificidad , Hidróxido de Sodio/química , Esputo/microbiología , Tuberculosis/microbiologíaRESUMEN
The hydrogen storage system LiH + NH(3) â LiNH(2) + H(2) is one of the most promising hydrogen storage systems, where the reaction yield can be increased by replacing Li in LiH with other alkali metals (Na or K) in order of Li < Na < K. In this paper, we have studied the alkali metal M (M = Li, Na, K) dependence of the reactivity of MH with NH(3) by calculating the potential barrier of the H(2) desorption process from the reaction of an M(2)H(2) cluster with an NH(3) molecule based on the ab initio structure optimization method. We have shown that the height of the potential barrier becomes lower in order of Li, Na, and K, where the difference of the potential barrier in Li and Na is relatively smaller than that in Na and K, and this tendency is consistent with the recent experimental results. We have also shown that the H-H distance of the H(2) dimer at the transition state takes larger distance and the change of the potential energy around the transition state becomes softer in order of Li, Na, and K. There are almost no M dependence in the charge of the H atom in NH(3) before the reaction, while that of the H atom in M(2)H(2) takes larger negative value in order of Li, Na, and K. We have also performed molecular dynamics simulations on the M(2)H(2)-NH(3) system and succeeded to reproduce the H(2) desorption from the reaction of Na(2)H(2) with NH(3).
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In the present study, to elucidate the influences of the deficiency of teeth on the masseter muscle, we analyzed changes in the expression of MyHC isoform mRNAs during postnatal development in mi/mi mice using real-time PCR. By 8 weeks of age, MyHC I had nearly disappeared in the +/+ mice, while it was still present in the mi/mi, and the level of MyHC I mRNA in the mi/mi was 5.1-fold higher than that in the +/+ (p<0.01). The levels of MyHC IIx mRNAs in the mi/mi mice were 41 ~ 55% lower than those in the +/+ at both 3 weeks and 4 weeks of age (p<0.05). No significant difference in the expression of MyHC IIa and IIb mRNAs in the masseter muscle was found between the mi/mi and +/+. From these results, we speculate that the deficiency of teeth affects the masseter muscles during the postnatal development.
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Synaptogenesis in the neuromuscular junction involves a nicotinic acetylcholine receptor (nAChR) switch and elimination. The microphthalmic mouse (mi/mi) with a mutation in the mitf gene cannot perform occlusal activity, because its teeth do not erupt. The present study attempted to elucidate the contribution of occlusal activity to synaptogenesis in masticatory muscles. In the masseter of the mi/mi, the nAChR elimination initiated, but did not progress normally, after 3 weeks of age, when the occlusal activity emerged in the +/+ mouse, whereas the nAChR switch progressed normally during the entire period of synaptogenesis. The mRNA expression patterns of nAChR subunits in the temporalis and digastric of the mi/mi differed from those in its masseter. These findings suggest that, in the masseter, occlusal activity is essential for the completion of nAChR elimination, but not for the nAChR switch, and that the contribution of occlusal activity to synaptogenesis varies among the masticatory muscles.
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Oclusión Dental , Músculo Masetero/inervación , Neurogénesis/fisiología , Sinapsis/fisiología , Envejecimiento/patología , Envejecimiento/fisiología , Animales , Peso Corporal , Dieta , Femenino , Inmunohistoquímica , Masculino , Músculo Masetero/anatomía & histología , Ratones , Ratones Mutantes , Factor de Transcripción Asociado a Microftalmía/genética , Microftalmía/genética , Músculo Esquelético/anatomía & histología , Músculo Esquelético/inervación , Mutación/genética , Músculos del Cuello/anatomía & histología , Músculos del Cuello/inervación , Unión Neuromuscular/fisiología , Tamaño de los Órganos , Receptores Nicotínicos/análisis , Receptores Nicotínicos/fisiología , Músculo Temporal/anatomía & histología , Músculo Temporal/inervación , Erupción Dental/fisiologíaRESUMEN
Eighteen patients with hematologic malignancies underwent cord blood transplantation (CBT) from unrelated donors after being conditioned with myeloablative or reduced-intensity regimens, and received tacrolimus and methotrexate (15 mg/m(2) on day 1, 10 mg/m(2) on days 3 and 6) as graft-versus-host disease (GVHD) prophylaxis. The median number of nucleated cells in infused cord blood was 2.66 x 10(7)/kg (range 1.90 to 4.15 x 10(7)/kg). Engraftment was achieved in 16 of 18 patients. The median time to absolute neutrophil count >0.5 x 10(9)/L was 21.5 days (range 17 to 32), and the median time to platelet count >2.0 x 10(9)/L was 36 days (range 26 to 57). Of the 16 evaluable patients, five and eight had grades I and II acute GVHD, respectively, and none had grades III/IV acute GVHD. The cumulative incidence of grade II acute GVHD was 44.4%. Chronic GVHD occurred in 7 of 15 evaluable patients: limited type in three patients, extensive type in four patients. Of the 18 patients, 14 were alive and disease-free between 173 and 1514 days after CBT (median 746 days). The probability of disease-free survival at 2 years was 79.1%. These results, although in a retrospective study, suggested that tacrolimus and short-term methotrexate effectively prevented the occurrence of severe acute GVHD after unrelated CBT, and may contribute to a high survival rate.
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Trasplante de Células Madre de Sangre del Cordón Umbilical/efectos adversos , Enfermedad Injerto contra Huésped/prevención & control , Neoplasias Hematológicas/terapia , Metotrexato/uso terapéutico , Tacrolimus/uso terapéutico , Adulto , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunosupresores/uso terapéutico , Leucemia/terapia , Recuento de Leucocitos , Linfoma/terapia , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/terapia , Neutrófilos , Probabilidad , Acondicionamiento PretrasplanteRESUMEN
Lymphoproliferative disease of granular lymphocytes (LDGL) is a disorder characterized by the clonal expansion of granular lymphocytes. It has recently been shown that the clonal expansion of granular lymphocytes occurs in patients with paroxysmal nocturnal hemoglobinuria (PNH) in a subclinical fashion. To test the possibility that LDGL patients share a PNH phenotype, we obtained peripheral blood cells from 20 patients with LDGL and examined the expression of the glycosylphosphatidyl inositol (GPI)-anchored proteins, CD55 and CD59. Compared with normal controls, however, a defective expression of CD55/59 was not observed on either granulocytes or erythrocytes from LDGL patients. An unexpected finding was the significantly lower CD55/59 expression on granular lymphocytes from patients with CD16(+)CD56(-) phenotype LDGL than from patients with CD16(+)CD56(+) phenotype LDGL, or natural killer (NK) and NK/T lymphocytes from healthy individuals. The positive correlation between the expression of CD56 and CD55/59 might have some relevance to the functional properties of the CD56(+) subset of large granular lymphocytes.
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Antígenos CD55/biosíntesis , Antígenos CD59/biosíntesis , Regulación de la Expresión Génica , Células Asesinas Naturales/metabolismo , Trastornos Linfoproliferativos/metabolismo , Linfocitos T/metabolismo , Femenino , Hemoglobinuria Paroxística/metabolismo , Hemoglobinuria Paroxística/patología , Humanos , Células Asesinas Naturales/patología , Trastornos Linfoproliferativos/patología , Masculino , Linfocitos T/patologíaRESUMEN
OBJECTIVE: The mechanism regulating skeletal muscle mass is unclear. The purpose of the present study was to investigate the extent to which insulin-like growth factors (IGFs), their receptors (IGFRs), and binding proteins (IGFBPs) are involved in the regulation of skeletal muscle mass. DESIGN: We measured the mRNA expression levels for IGFs, IGFRs, and IGFBPs in the rat masseter muscle hypertrophied by oral administration of clenbuterol for 3 weeks and determined the correlations between the weight of masseter muscle and the mRNA expression levels. RESULTS: The mRNA expression levels for IGF-I and II, IGFR1 and 2, and IGFBP4 and 6 showed clenbuterol-induced elevations and positive correlations with the weight of masseter muscle. That for IGFBP3 only exhibited a clenbuterol-induced decrease and a strong negative correlation with the weight of masseter muscle. The mRNA expression levels for IGFBP2 and 5 showed no significant changes between the control and clenbuterol groups, and no significant correlations. IGFBP1 mRNA was not detectable. CONCLUSION: These results suggest that IGF-I, II, IGFR1 and 2, and IGFBP3, 4 and 6 are related to the mechanism regulating masseter muscle mass in the rat.
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Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Músculo Masetero/efectos de los fármacos , ARN Mensajero/metabolismo , Receptores de Somatomedina/metabolismo , Somatomedinas/metabolismo , Agonistas Adrenérgicos beta/farmacología , Animales , Clenbuterol/farmacología , Hipertrofia/inducido químicamente , Masculino , Músculo Masetero/anatomía & histología , Músculo Masetero/metabolismo , Músculo Esquelético/anatomía & histología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , RatasRESUMEN
This review summarizes findings concerning the unique developmental characteristics of mouse head muscles (mainly the masticatory and tongue muscles) and compares their characteristics with those of other muscles. The developmental origin of the masticatory muscles is the somitomeres, whereas the tongue and other muscles, such as the trunk (deep muscles of the back, body wall muscles) and limb muscles, originate from the somites. The program controlling the early stages of masticatory myogenesis, such as the specification and migration of muscle progenitor cells, is distinctly different from those in trunk and limb myogenesis. Tongue myogenesis follows a similar regulatory program to that for limb myogenesis. Myogenesis and synaptogenesis in the masticatory muscles are delayed in comparison with other muscles and are not complete even at birth, whereas the development of tongue muscles proceeds faster than those of other muscles and ends at around birth. The regulatory programs for masticatory and tongue myogenesis seem to depend on the developmental origins of the muscles, i.e., the origin being either a somite or somitomere, whereas myogenesis and synaptogenesis seem to progress to serve the functional requirements of the masticatory and tongue muscles.
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Músculos Masticadores , Desarrollo de Músculos/fisiología , Lengua , Animales , Humanos , Músculos Masticadores/anatomía & histología , Músculos Masticadores/embriología , Músculos Masticadores/crecimiento & desarrollo , Músculo Esquelético/anatomía & histología , Músculo Esquelético/crecimiento & desarrollo , Músculo Esquelético/fisiología , Receptores Colinérgicos/fisiología , Sinapsis/fisiología , Lengua/anatomía & histología , Lengua/embriología , Lengua/crecimiento & desarrolloRESUMEN
SGN-30, a monoclonal antibody with activity against CD30+ malignancies, is currently in phase II clinical evaluation for treatment of Hodgkin's disease (HD) and anaplastic large cell lymphoma. The mechanisms underlying SGN-30's antitumor activity were investigated using cDNA array of L540 cells. SGN-30 treatment activated NF-kappaB and modulation of several messages including the growth regulator p21WAF1/CIP1 (p21) and cellular adhesion marker ICAM-1. p21 protein levels increased coincident with growth arrest and Annexin V/PI staining in treated HD cells. To determine if SGN-30-induced growth arrest would sensitize tumor cells to chemotherapeutics used against HD, L540cy and L428 cells were exposed to SGN-30 in combination with a panel of cytotoxic agents and resultant interactions quantified by the Combination Effects Method. Interactions between SGN-30 and all cytotoxic agents examined were additive or better. These in vitro data translated to increased efficacy of SGN-30 and bleomycin against L540cy tumor xenografts. In addition to direct cell killing, SGN-30 affects growth arrest and drug sensitization through growth regulating and proapoptotic machinery. Importantly, these data suggest that SGN-30 can enhance the efficacy of standard chemotherapies used to treat patients with CD30+ malignancies.
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Anticuerpos Monoclonales/uso terapéutico , Enfermedad de Hodgkin/tratamiento farmacológico , Enfermedad de Hodgkin/inmunología , Antígeno Ki-1/inmunología , Transducción de Señal/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Apoptosis/efectos de los fármacos , Bleomicina/uso terapéutico , Ciclo Celular/efectos de los fármacos , Ciclo Celular/inmunología , Línea Celular Tumoral , Quimioterapia Combinada , Enfermedad de Hodgkin/genética , Humanos , Antígeno Ki-1/efectos de los fármacos , Ratones , Ratones SCID , FN-kappa B/efectos de los fármacos , FN-kappa B/inmunología , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Sensibilidad y Especificidad , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto/métodosRESUMEN
The developmental stages of and places for the proliferation of tongue muscle cells have not yet been determined. To determine the stages of and places for proliferation between embryonic day (E) 9 and birth, we analyzed the expression of cyclin D1 mRNA and the immunolocalization for proliferating cell nuclear antigen (PCNA). The ratio of PCNA-positive nuclei to total nuclei (PCNA-labeling index) was obtained in the anterior, middle, and posterior regions. Cyclin D1 mRNA was highly expressed between E11 and E13, but decreased thereafter until birth. The distribution of PCNA-positive cell nuclei was consistent with that of myogenic cells in the occipital somites at E9. The PCNA-labeling index was highest at E11, then decreased until birth without a significant difference among the 3 regions. These findings suggest that some tongue muscle progenitor cells begin proliferation in the occipital somites at E9, and that the proliferation in the whole tongue region occurred most actively between E11 and E13, then decreased until birth without regional differences.
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Desarrollo de Músculos/fisiología , Músculo Esquelético/embriología , Lengua/embriología , Animales , Diferenciación Celular/fisiología , Núcleo Celular/ultraestructura , Proliferación Celular , Ciclina D1/análisis , Edad Gestacional , Inmunohistoquímica , Ratones , Ratones Endogámicos ICR , Antígeno Nuclear de Célula en Proliferación/análisis , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Somitos/citologíaRESUMEN
A soft diet facilitates the development of faster-type fibres in rat masseter muscle in the 9 days after weaning compared with a hard diet. To determine whether insulin-like growth factors (IGFs), IGF receptors (IGFRs) and IGF binding proteins (IGFBPs) are involved in this fibre-type alteration, the expression of myosin heavy chain (MHC), IGF, IGFR and IGFBP mRNAs in the masseter muscle of rats fed a hard or soft diet for 9 days after weaning was analysed using competitive, reverse transcriptase-polymerase chain reaction. A soft diet decreased the expression of MHC IIa (slower type) by 70%, but increased the expression of MHC IIx (intermediate type) and IIb (faster type) by 80 and 582%, respectively, compared with a hard diet. These findings verified that a soft diet facilitates the development of faster-type fibres in rat masseter muscle compared with a hard diet. A soft diet induced reductions of 25-76% (P < 0.05-0.01) in the expression of IGF-I, IGF-II, IGFR2, IGFBP4 and IGFBP6 compared with a hard diet, but induced a 25% (P < 0.05) increase only in expression of IGFBP3. These findings suggest that the changes in expression of IGF-I, IGF-II, IGFR2, IGFBP3, IGFBP4 and IGFBP6 are associated with the fibre-type alteration of rat masseter muscle in response to diet consistency soon after weaning.
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Alimentos , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/análisis , Músculo Masetero/metabolismo , Receptores de Somatomedina/análisis , Somatomedinas/análisis , Animales , Factor I del Crecimiento Similar a la Insulina/análisis , Factor II del Crecimiento Similar a la Insulina/análisis , Masculino , Músculo Masetero/crecimiento & desarrollo , Cadenas Pesadas de Miosina/análisis , Fibras Nerviosas/metabolismo , ARN Mensajero/análisis , Ratas , Ratas Wistar , Receptor IGF Tipo 1/análisis , Receptor IGF Tipo 2/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , DesteteRESUMEN
No published study on synaptogenesis in masseter muscle has focused on the shift of nicotinic acetylcholine receptors (nAChRs) from the embryonic type (alpha(2)-, beta-, gamma- and delta-subunits) to the adult-type (alpha(2)-, beta-, epsilon- and delta-subunits) and the elimination of nAChRs outside the neuromuscular junction. To identify the time course of the nAChR transitions in rat masseter muscle between 1 and 63 days of age, the expression of delta-, epsilon- and gamma-subunit mRNAs was analysed by competitive polymerase chain reaction in combination with reverse transcription. The expression of the delta-subunit was high between 1 and 7 days of age, then decreased by 95% (P<0.0001) between 7 and 28 days, suggesting that the nAChR elimination occurs during this period. The quantity of the epsilon-subunit increased by approximately 600% (P<0.0001) between 1 and 21 days of age, whereas the quantity of the gamma-subunit decreased by 85% (P<0.0001) during the same period. This result indicates that the nAChR type shift is terminated at 21 days of age. The feeding behaviour of the rats inevitably changed from suckling to biting after 19 days of age, because they were weaned at that age. As the nAChR type shift was terminated soon after weaning, the termination could be related to the change in feeding behaviour. However, it might also be the case that nAChR elimination is not directly related to the change in feeding behaviour, as the elimination continued at the same rate for 9 days after weaning (from 19 to 28 days of age).
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Músculo Masetero/inervación , Receptores Nicotínicos/química , Animales , Animales Lactantes , Electroforesis en Gel de Agar , Unión Neuromuscular/química , Subunidades de Proteína , ARN Mensajero/biosíntesis , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SinapsisRESUMEN
To study the effects of diet consistency on the fiber phenotypes of rat masseter (1-70 days of age), the mRNAs of myosin heavy chain isoforms (MHC embryonic, neonatal, I, IIa, IId/x and IIb) were measured in total RNA preparations from masseters of hard-diet group (HDG) and soft-diet group (SDG) by competitive reverse transcriptase-polymerase chain reaction (RT-PCR). With respect to the time course of the transition of each MHC mRNA expressed as a percentage relative to the maximum mean, the soft diet facilitated early (9 days after weaning) expression of IId/x and IIb isoforms, and also a decline in the expression of neonatal and IIa isoforms. The expression of neonatal, IIa and IId/x isoforms at 70 days of age was significantly (P<0.05, P<0.01, P<0.01, respectively) lower in SDG than in HDG, indicating a higher relative composition of the IIb isoform in the SDG. Embryonic MHC mRNA had disappeared by 14 days of age (i.e. before weaning at 19 days). No MHC I mRNA was observed in any masseter studied. These results suggest that in the rat a soft diet facilitates an even more MHC IIb-rich phenotype in the masseter muscle than a hard diet.
Asunto(s)
Dieta , Músculo Masetero/crecimiento & desarrollo , Cadenas Pesadas de Miosina/genética , Miosinas del Músculo Esquelético/genética , Animales , Regulación de la Expresión Génica , Dureza , Isoformas de Proteínas/genética , ARN Mensajero/análisis , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Analysis of hematopoietic chimerism is important for monitoring engraftment, graft failure, and disease recurrence. Although several techniques are now available, their sensitivity is unsatisfactory. In sex-mismatched stem cell transplantation (SCT) with a female donor, Y chromosome-specific sequences have proven the most sensitive marker. However, in the case of a male donor, no such reliable marker has been available to date. In this study, we report a novel method we developed to detect microchimerism in female recipients who receive SCT from male donors. The X-linked human androgen receptor gene (HUMARA) contains a highly polymorphic CAG trinucleotide repeat. Near this polymorphic site are methyl-sensitive HpaII restriction enzyme sites. After HpaII digestion, unmethylated male HUMARA sequences are completely digested, while methylated female ones remain intact among the male origin cells. This allows a highly efficient detection of a small number of female cells. Combined with the nested PCR technique, the X chromosome methylation-based chimerism assay could attain a 10(-4) level of sensitivity, which is 1000-fold higher than that of conventional assays. The applicability of the method was confirmed in two transplant cases. This highly sensitive method can also be applied to detect minimal residual disease or microchimerism in conditions other than hematopoietic SCT.