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AIM: To evaluate the efficacy of a prototype root canal dressing containing surface pre-reacted glass-ionomer (S-PRG) fillers on repairing induced periapical lesions in a rat model. Calcium hydroxide [Ca(OH)2 ] was applied as a comparison in the healing process. METHODOLOGY: The pulp chambers of the maxillary first molars in 64 male Wistar rats aged 16 weeks were opened to induce periapical lesions. After 28 days, the mesial canal of each tooth was prepared, irrigated with 2.5% sodium hypochlorite only (control group: irrigation) or followed by the respective dressing [Ca(OH)2 group, irrigation + Ca(OH)2 ; S-PRG group, irrigation + S-PRG] and restored with composite resin for 3 or 7 days (10/group). Four rats with healthy molars were used as blank controls. Descriptive analysis of the periapical radiographs, haematoxylin and eosin staining and immunohistochemical observation was performed 3 and 7 days after treatment. The periapical grey value, CD68 macrophages and osteoclasts (cathepsin-K) were quantified and statistically analysed with Tukey's honest significant difference test. A significant difference was achieved when P values were <0.05. RESULTS: S-PRG and Ca(OH)2 dressings were associated with increased periapical grey values and inhibited osteoclast activity at 3 and 7 days; a significant difference in radiographic results and the number of osteoclasts was obtained at 3 and 7 days compared with the control group (P < 0.05). Reparative tissue was observed histologically in the space of the periapical resorbed necrotic area after S-PRG and Ca(OH)2 treatment for 3 and 7 days. The number of macrophages was significantly decreased at 3 and 7 days in the S-PRG and Ca(OH)2 specimens when compared with the controls (P < 0.05). CONCLUSIONS: In a rat experimental model, the S-PRG root canal dressing was comparable to Ca(OH)2 in promoting the healing of experimentally induced periapical lesions. S-PRG paste has the potential to be used as an alternative intracanal dressing in teeth with apical periodontitis.
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Periodontite Periapical , Materiais Restauradores do Canal Radicular , Animais , Bandagens , Hidróxido de Cálcio , Cavidade Pulpar , Masculino , Periodontite Periapical/terapia , Ratos , Ratos Wistar , Irrigantes do Canal RadicularRESUMO
OBJECTIVES: The aim of this study was to investigate the association between different intensities and frequencies of non-occupational physical activity (PA) and the risk of dementia among Japanese older adults. STUDY DESIGN: This was a prospective cohort study. METHODS: A total of 2194 participants aged ≥65 years from the Japan Gerontological Evaluation Study were followed up between 2010 and 2016. The standardised dementia scale of the long-term care insurance system was used to identify incident dementia, whereas non-occupational PA (<2 or ≥2 times/week on each intensity: light, moderate and vigorous) was assessed using a questionnaire. Cox regression was used to compute the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident dementia. RESULTS: After adjustment for sociodemographic and medical characteristics, the following frequencies and intensities of non-occupational PA, compared with no non-occupational PA at all, were associated with a reduced risk of dementia: light PA ≥2 times/week (HR = 0.61, 95% CI: 0.38-0.97), moderate PA <2 times/week (HR = 0.46, 95% CI: 0.28-0.76), moderate PA ≥2 times/week (HR = 0.57, 95% CI: 0.36-0.91), vigorous PA <2 times/week (HR = 0.40, 95% CI: 0.21-0.74) and vigorous PA ≥2 times/week (HR = 0.29, 95% CI: 0.15-0.57). In the sex-specific analysis, moderate PA <2 times/week and vigorous PA ≥2 times/week were associated with a reduced risk of dementia in men, whereas light and moderate PA ≥2 times/week and all frequencies of vigorous PA were associated with a reduced risk of dementia in women. CONCLUSIONS: Practicing non-occupational PA was associated with a reduced risk of dementia among Japanese older adults.
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Demência , Exercício Físico , Idoso , Demência/epidemiologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Estudos Prospectivos , Inquéritos e QuestionáriosRESUMO
BACKGROUND: The role of completion lymph node dissection (CLND) in patients with sentinel lymph node (SLN)-positive melanoma continues to be debated. This systematic review and meta-analysis evaluated survival and recurrence rate in these patients who underwent CLND, compared with observation. METHODS: A comprehensive MEDLINE and Embase database search was performed for cohort studies and RCTs published between January 2000 and June 2017 that assessed the outcomes of CLND compared with observation in patients with SLN-positive melanoma. The primary outcome was survival and the secondary outcome was recurrence rate. Studies were assessed for quality using the Cochrane risk-of-bias tool for RCTs and Newcastle-Ottawa Scale for cohort studies. Pooled relative risk or hazard ratio with 95 per cent confidence intervals were calculated for each outcome. The extent of heterogeneity between studies was assessed with the I2 test. The protocol was registered in PROSPERO (CRD42017070152). RESULTS: Fifteen studies (13 cohort studies with 7868 patients and 2 RCTs with 2228 patients) were identified for qualitative synthesis. Thirteen studies remained for quantitative meta-analysis. Survival was similar in patients who underwent CLND and those who were observed (risk ratio (RR) for death 0·85, 95 per cent c.i. 0·71 to 1·02). The recurrence rate was also similar (RR 0·91, 0·79 to 1·05). CONCLUSION: Patients with SLN-positive melanoma do not have a significant benefit in survival or recurrence rate if they undergo CLND rather than observation.
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Excisão de Linfonodo/métodos , Melanoma/cirurgia , Linfonodo Sentinela/patologia , Neoplasias Cutâneas/cirurgia , Humanos , Metástase Linfática , Melanoma/mortalidade , Melanoma/patologia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Resultado do Tratamento , Conduta ExpectanteRESUMO
A 70-year-old man presented to our clinic with a 10-year history of recurrent pruritic erythema and plaques on his trunk and limbs. Based on the pathological findings and monoclonal rearrangement of the T-cell receptor (TCR)-Cß1 gene, mycosis fungoides (T2N0M0B0 stage IB) was diagnosed. Despite combination therapy including histone deacetylase inhibitor (vorinostat), the symptoms slowly evolved into Sézary syndrome (SS; T4N1M0B2) over 4 years, with dense infiltrates due to atypical lymphocytes expressing CCR4 developing in the entire dermis. Anti-CCR4 monoclonal antibody (mogamulizumab) treatment was started. After seven courses, the CCR4-positive atypical lymphocytes decreased in the dermis to levels below those seen at the outset of treatment. To our knowledge, there is no previous report of a case of SS managed with vorinostat followed by mogamulizumab demonstrating such a remarkable change in the pathological state following treatment.
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Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Inibidores de Histona Desacetilases/uso terapêutico , Ácidos Hidroxâmicos/uso terapêutico , Receptores CCR4/antagonistas & inibidores , Síndrome de Sézary/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Humanos , Masculino , Síndrome de Sézary/patologia , Pele/patologia , Neoplasias Cutâneas/patologia , VorinostatRESUMO
Previously, a single nucleotide polymorphism (SNP) related to gait type was identified at position 22 999 655 of chromosome 23 in the coding region of DMRT3 (DMRT3:Ser301Ter) by showing that a cytosine (C) to adenine (A) mutation of this SNP induced pace in the Icelandic horse. We investigated the effect of DMRT3:Ser301Ter on the gait of Hokkaido Native Horses, a Japanese native breed, and examined genetic factors other than DMRT3 by exploring genome-wide SNPs related to gait determination. All animals exhibiting pace were AA for DMRT3:Ser301Ter, confirming the association of DMRT3:Ser301Ter with gait determination; however, 14.3% of the animals exhibiting trot also had AA for DMRT3:Ser301Ter, suggesting the presence of another factor(s) cooperatively working with DMRT3:Ser301Ter for gait determination. SNPs on chromosomes 13 and 23 were detected by genome-wide association analysis (false discovery rate <0.05), although SNPs on chromosome 23 were all located in the vicinity of DMRT3:Ser301Ter, confirming the association with DMRT3. A genome-wide association study targeting only animals with AA for DMRT3:Ser301Ter to examine genetic factors cooperatively working with DMRT3:Ser301Ter for gait determination suggested associations of 23 SNPs on six chromosomes. In a series of analyses of the effect of a maternal factor (dam's gait) on gait determination, the effect was suggested in comparison of the frequencies of exhibiting pace in gait checks in only two animal groups having dams with different DMRT3:Ser301Ter genotypes (P < 0.05), suggesting that the gait of the dam does not have a major effect on whether progeny homozygous for the DMRT3:Ser301Ter mutation will preferentially pace or trot.
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Marcha , Cavalos/classificação , Cavalos/genética , Herança Materna , Fatores de Transcrição/genética , Animais , Estudo de Associação Genômica AmplaRESUMO
BACKGROUND: Few studies have been conducted on patterns of recurrence after resection for distal cholangiocarcinoma (DCC). The aim of this study was to investigate the incidence and pattern of recurrence after resection of DCC, and to evaluate prognostic factors for time to recurrence and recurrence-free survival (RFS). METHODS: Patients who underwent pancreatoduodenectomy with curative intent for DCC between 2001 and 2010 at one of 30 hospitals in Japan were reviewed retrospectively, with special attention to recurrence patterns. The Cox proportional hazards model was used for multivariable analysis. RESULTS: In the study interval, 389 patients underwent pancreatoduodenectomy for DCC with R0/M0 status. Recurrence developed in 213 patients (54·8 per cent). The estimated cumulative probability of recurrence was 54·3 per cent at 5 years. An initial locoregional recurrence occurred in 55 patients (14·1 per cent) and initial distant recurrence in 168 (43·2 per cent), most commonly in the liver. Isolated initial locoregional recurrence occurred in 45 patients (11·6 per cent). Independent prognostic factors for time to recurrence and RFS were perineural invasion (P = 0·001 and P = 0·009 respectively), pancreatic invasion (both P < 0·001) and lymph node metastasis (both P < 0·001). RFS worsened as the number of risk factors increased: the 5-year RFS rate was 70·6 per cent for patients without any risk factors, 50·3 per cent for patients with one factor, 31·8 per cent for those with two factors, and 13·4 per cent when three factors were present. CONCLUSION: More than half of patients with DCC experienced recurrence after R0 resection, usually within 5 years. Perineural invasion, pancreatic invasion and positive nodal involvement are risk factors for recurrence.
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Neoplasias dos Ductos Biliares/cirurgia , Colangiocarcinoma/cirurgia , Recidiva Local de Neoplasia/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/mortalidade , Colangiocarcinoma/mortalidade , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Recidiva Local de Neoplasia/mortalidade , Estudos Retrospectivos , Fatores de Risco , Resultado do TratamentoRESUMO
BACKGROUND: The phosphotidylinositol-3 kinase (PI3K)/serine-threonine kinase/mammalian target of rapamycin signaling pathway is frequently altered in head and neck squamous cell cancer (HNSCC). PX-866 is an oral, irreversible, pan-isoform inhibitor of PI3K. A phase I trial demonstrated tolerability of this combination. This randomized phase II study evaluated PX-866 combined with cetuximab in patients with advanced, refractory HNSCC. METHODS: Patients with recurrent or metastatic HNSCC who had received at least one and no more than two prior systemic treatment regimens were randomized (1 : 1) to cetuximab with or without PX-866 (8 mg p.o. daily; arms A and B, respectively). The primary end point was progression-free survival (PFS). Secondary end points included objective response rate (ORR), overall survival (OS), toxicity, and correlation of key biomarkers with efficacy outcomes. RESULTS: Eighty-three patients were enrolled. There was a similar response rate between arms (10% versus 7%). Of patients for whom tissue was assessable, 57% were human papillomavirus (HPV) positive. Median PFS was 80 days in both arms and there was no difference in OS between the two arms (211 versus 256 days). Overall toxicity was higher in arm A compared with arm B, especially in terms of nausea (53% versus 23%), vomiting (45% versus 15%), fatigue (43% versus 23%), diarrhea (40% versus 21%), and hypokalemia (25% versus 10%). Grade 3 or higher adverse events were infrequent, but more common in the combination arm although without a specific pattern. PIK3CA mutations were observed in 17% of the cases assessed, and PTEN loss was infrequently observed. CONCLUSION: The addition of PX-866 to cetuximab did not improve PFS, RR, or OS in patients with advanced, refractory HNSCC enrolled without molecular preselection. In this contemporary cohort, HPV-positive patients comprised the majority, and neither HPV-positive nor HPV-negative patients derived clinical benefit for the addition of cetuximab plus PX-866.
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Escamosas/tratamento farmacológico , Cetuximab/administração & dosagem , Gonanos/administração & dosagem , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico , Inibidores Enzimáticos/administração & dosagem , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
OBJECTIVE: This study aimed to use short-form visual analogue scale cochlear implantation questionnaires to evaluate subjective aspects at each out-patient visit. The correlation between subjective hearing tests using the short-form visual analogue scale and objective hearing outcomes was evaluated. METHOD: This study was conducted in a single centre. Cochlear implant users (n = 199) evaluated their hearing on a scale of 0 to 100 for the right, left and both ears. The Japanese speech perception test (CI-2004) Japanese monosyllable speech perception test (67-S) and cochlear implantation threshold were used for the objective cochlear implantation evaluation. RESULTS: A significant correlation was found between the short-form visual analogue scale questionnaire and objective hearing outcome, for words (r = 0.64) and sentences (r = 0.62) in CI-2004 and 67-S (r = 0.56) tests. No significant correlation was found between the short-form visual analogue scale score and cochlear implantation threshold (r = -0.18). CONCLUSION: Short-form visual analogue scale cochlear implantation questionnaires mean cochlear implant users spend less time answering subjective visual analogue scale questionnaires, and clinicians estimate a patient's cochlear implantation hearing and abnormality by chronological evaluation.
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Implante Coclear , Implantes Cocleares , Percepção da Fala , Humanos , Escala Visual Analógica , AudiçãoAssuntos
Carcinoma Basocelular/tratamento farmacológico , Imiquimode/administração & dosagem , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína Gli3 com Dedos de Zinco/metabolismo , Administração Cutânea , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Biópsia , Carcinoma Basocelular/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/efeitos dos fármacos , Pele/patologia , Creme para a Pele/administração & dosagem , Neoplasias Cutâneas/patologia , Resultado do TratamentoRESUMO
Quercetin, rutin, naringin, hesperidin and chrysin were tested as substrates for chloroperoxidase to produce reactive quinones to graft onto chitosan. Quercetin and rutin quinones were successfully chemically attached to low molecular weight chitosan. The quercetin-modified chitosan showed an enhancement of plastic, antioxidant and antimicrobial properties as well as of thermal degradability. Finally, chitosan-quercetin films visibly decreased enzymatic oxidation when applied to Opuntia ficus indica cladodes.
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Anti-Infecciosos/química , Antioxidantes/química , Quitosana/química , Cloreto Peroxidase/química , Aditivos Alimentares/química , Quercetina/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Calorimetria , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Cloreto Peroxidase/metabolismo , Cor , Flavanonas/química , Flavanonas/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Aditivos Alimentares/farmacologia , Hesperidina/química , Hesperidina/farmacologia , Reação de Maillard/efeitos dos fármacos , Opuntia/efeitos dos fármacos , Opuntia/metabolismo , Oxirredução , Caules de Planta/efeitos dos fármacos , Caules de Planta/metabolismo , Quercetina/farmacologia , Rutina/química , Rutina/farmacologia , EspectrofotometriaRESUMO
The Raman spectra of numerous dodecaborides have been measured on high-quality single crystals at ambient conditions with high spectral resolution and signal-to-noise ratio. Besides the strong Raman-active modes, numerous Raman-inactive modes occur in the spectra, indicating distortions of the structures. Ab initio calculation of the phonon spectra on ZrB(12) excellently agrees with the experimental results. Force constants are theoretically calculated and force parameters are estimated from the Raman frequencies. The influence of the surface range on the Raman spectra is evident. The different isotopic effects (virtual crystal approximation, the polarization effect and the effect of isotopic disorder) on the phonon frequencies are determined, separated and discussed.
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AIMS: Glimepiride, a third generation sulfonylurea (SU), is known to have extrapancreatic effects, but its vascular effect is unclear. We investigated the efficacy of glimepiride in improving arterial stiffness assessed by cardio-ankle vascular index (CAVI) in type 2 diabetic patients, compared with glibenclamide, a conventional SU. METHODS: Forty type 2 diabetic patients were randomly assigned to two groups. One group was administered glimepiride 1.5 mg/day, and the other group was administered glibenclamide 1.25 mg/day for 6 months. RESULTS: No significant difference in hypoglycaemic effect was observed between two groups. CAVI significantly decreased only in glimepiride group (9.4 ± 1.4â8.9 ± 0.8, p < 0.05). Decrease in CAVI was greater in glimepiride group than in glibenclamide group (-0.50 ± 0.98 vs. -0.04 ± 0.57, p = 0.048). Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) decreased in glimepiride group and increased in glibenclamide group, and the changes were significantly different between groups (-1.5 ± 3.5 vs. + 1.8 ± 3.6, p = 0.009); whereas serum lipoprotein lipase mass increased in glibenclamide group and decreased in glibenclamide group, and the changes tended to be different between groups (+ 2.1 ± 19.1 vs. -7.4 ± 19.2, p = 0.096). Change in urinary 8-OHdG was a significant independent predictor for change in CAVI in all subjects. CONCLUSIONS: These results suggest that glimepiride improves CAVI compared with glibenclamide. Reduced oxidative stress and improved insulin resistance may contribute to the improvement of CAVI by glimerpiride.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/tratamento farmacológico , Glibureto/uso terapêutico , Hipoglicemiantes/uso terapêutico , Compostos de Sulfonilureia/uso terapêutico , Rigidez Vascular/efeitos dos fármacos , 8-Hidroxi-2'-Desoxiguanosina , Idoso , Tornozelo/irrigação sanguínea , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Resistência Vascular/efeitos dos fármacosRESUMO
Acute radiation tongue mucositis has a profound effect on talking and eating. We examined whether the dose-volume histogram obtained from the tongue surface model correlates with mucositis severity, and whether it is useful for predicting acute radiation tongue mucositis in patients with head and neck cancer treated with intensity-modulated radiation therapy. Thirty-six patients who received intensity-modulated radiation therapy for head and neck cancer were analysed for acute radiation tongue mucositis according to the Common Terminology Criteria for Adverse Events, version 4.0, as well as the Radiation Therapy Oncology Group scoring systems. The corresponding high-dose locations in anatomical sub-regions in the tongue surface model and the development of high-grade acute radiation tongue mucositis were compared. The mucositis sites coincided with the high-dose anatomical sub-regions in the tongue surface model. There was a clear dose-response relationship between the mean dose to the tongue and the acute radiation tongue mucositis Radiation Therapy Oncology Group grade. According to the dose-volume histogram, patients receiving 16.0-73.0 Gy to the tongue were susceptible to grade 2-3 toxicity. The tongue surface model can predict the site and severity of acute radiation tongue mucositis. In future, radiation treatment plans ccould be optimized using this model.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Mucosite , Radioterapia de Intensidade Modulada , Humanos , Dosagem Radioterapêutica , LínguaRESUMO
The Hayabusa2 spacecraft investigated the small asteroid Ryugu, which has a rubble-pile structure. We describe an impact experiment on Ryugu using Hayabusa2's Small Carry-on Impactor. The impact produced an artificial crater with a diameter >10 meters, which has a semicircular shape, an elevated rim, and a central pit. Images of the impact and resulting ejecta were recorded by the Deployable CAMera 3 for >8 minutes, showing the growth of an ejecta curtain (the outer edge of the ejecta) and deposition of ejecta onto the surface. The ejecta curtain was asymmetric and heterogeneous and it never fully detached from the surface. The crater formed in the gravity-dominated regime; in other words, crater growth was limited by gravity not surface strength. We discuss implications for Ryugu's surface age.
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BACKGROUND AND OBJECTIVE: A blood supply is indispensable for the regeneration of damaged or lost periodontal ligament (PDL) tissue. Mesenchymal stem cell-like activity of cells derived from the PDL has been identified by their capacity to form fibrous and osseous tissue and cementum. However, it remains to be clarified whether the cells have an ability to build the capillary network of blood vessels. This study evaluated the potential of cells derived from the PDL to construct a blood vessel-like structure and examined how growth factors controlled the multipotency of the cells. MATERIAL AND METHODS: The ability of a swine PDL fibroblast cell line, TesPDL3, to construct a blood vessel-like structure was evaluated on and in the self-assembling peptide scaffold, PuraMatrix(TM). In addition, the ability of the cells to form mineralized nodules was evaluated on type I collagen-coated plastic plates. In some cases, fibroblast growth factor (FGF)-2 and bone morphogenetic protein (BMP)-2 were added to these cultures. The status of the expression of vascular and osteoblastic cell-specific markers in the cells was evaluated using reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting and immunofluorescence analyses. RESULTS: The TesPDL3 cells not only formed mineralized nodules in response to BMP-2 stimulation but also constructed tube-like structures in response to FGF-2 stimulation. Intriguingly, FGF-2 inhibited the BMP-2-induced formation of mineralized nodules. Conversely, BMP-2 inhibited the FGF-2-induced formation of tube-like structures. CONCLUSION: Periodontal ligament fibroblasts have the potential to differentiate not only into osteoblastic but also into vascular cell lineages. The destiny of the cells was reciprocally regulated by BMP-2 and FGF-2.
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Proteína Morfogenética Óssea 2/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Multipotentes/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Ligamento Periodontal/citologia , Animais , Proteína Morfogenética Óssea 2/antagonistas & inibidores , Calcificação Fisiológica/fisiologia , Técnicas de Cultura de Células , Linhagem Celular , Células Clonais/citologia , Células Clonais/efeitos dos fármacos , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Músculo Liso/citologia , Músculo Liso/efeitos dos fármacos , Neovascularização Fisiológica/fisiologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Proteína Smad7/fisiologia , Sus scrofa , Alicerces TeciduaisRESUMO
A recent discovery of complicated isotope shifts of the PL 1014 meV line in Cu-containing silicon, which was made by Thewalt's group, indicates that existing models of Cu pairs are not appropriate for accounting for the luminescence center. A new structural model has been studied. First-principles calculations show that the most probable form of the complex is a four-membered complex which is composed of a substitutional Cu associated with three neighboring interstitial Cu atoms. The symmetry is C(3v). The formation mechanism of this complex is discussed. For interpreting the complicated splitting for the Γ(4) exciton peak, involvement of a non-totally symmetric mode is proposed. The pattern of splitting obtained by this model is almost in agreement with the experiment. Selection rules beyond the usual treatments are necessary to connect a specific exciton peak to the corresponding phonon.
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The aim of this study was to investigate the selectivity of chitosan for cadmium, copper and lead in the presence and absence of natural organic matter (NOM) in different pH solutions. Adsorption isotherms of one and three adsorbates at initial concentration of 5-100mg/L were carried out in batch reactors at pH 4, 5, or 7 and 25 degrees C in reactive and clarified water. The chitosan employed had a MW of 107.8 x 10(3)g/mol and degree of acetylation (DA) of 33.7%. The chitosan adsorption capacity at pH 4 in reactive water was 0.036, 0.016, 0.010mmol/g for Pb(2+), Cd(2+), and Cu(2+), respectively, and it decreased for Pb(2+) and Cd(2+) in clarified water. Conversely, experiments carried out in clarified water showed that the cadmium adsorption capacity of chitosan was enhanced about three times by the presence of NOM at pH 7: an adsorption mechanism was proposed. Furthermore, it was found that the biosorbent selectivity, in both reactive and clarified water at pH 4, was as follows Cu(2+)>Cd(2+)>Pb(2+). Finally, the preliminary desorption experiments of Cd(2+) conducted at pH 2 and 3 reported 68 and 44.8% of metal desorbed, which indicated that the adsorption mechanism occurred by electrostatic interactions and covalent bonds.
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Cádmio/isolamento & purificação , Quitosana/análise , Cobre/isolamento & purificação , Chumbo/isolamento & purificação , Acetilação , Adsorção , Cádmio/análise , Quitosana/química , Cobre/análise , Concentração de Íons de Hidrogênio , Íons , Chumbo/análise , Espectroscopia de Ressonância Magnética , Peso Molecular , Solubilidade , Soluções , Espectrofotometria Infravermelho , Temperatura , Termodinâmica , ÁguaRESUMO
The Hayabusa2 spacecraft arrived at the near-Earth carbonaceous asteroid 162173 Ryugu in 2018. We present Hayabusa2 observations of Ryugu's shape, mass, and geomorphology. Ryugu has an oblate "spinning top" shape, with a prominent circular equatorial ridge. Its bulk density, 1.19 ± 0.02 grams per cubic centimeter, indicates a high-porosity (>50%) interior. Large surface boulders suggest a rubble-pile structure. Surface slope analysis shows Ryugu's shape may have been produced from having once spun at twice the current rate. Coupled with the observed global material homogeneity, this suggests that Ryugu was reshaped by centrifugally induced deformation during a period of rapid rotation. From these remote-sensing investigations, we identified a suitable sample collection site on the equatorial ridge.
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PURPOSE: Changes in body composition of college wrestlers undergoing rapid weight reduction were evaluated over time using magnetic resonance imaging (MRI). METHODS: This study evaluated 12 wrestlers (male, 18-22 years of age) who participated in Japan's 2005 intercollegiate wrestling tournament. For this study, MRI (of the right femoral region and the trunk), as well as measurements of body weight, body fat percentage and body water content, were performed 1 month and 1 week prior to the weigh-in, on the day of the weigh-in, on the day of the match (after the match), and 1 week after the weigh-in. A survey of food and fluid intake was also conducted. RESULTS: Several variables were significantly lower on the day of the weigh-in than one month prior: body weight (p<0.01, -7.3% (SD 1.6%)); body fat (p<0.05, -9.3 (5.8)%); body water content (p<0.01, -5.9 (1.6)%); trunk cross-section (p<0.01, -13.2 (4.4)%), including separate measurements of trunk viscera, trunk muscle, and trunk fat; quadriceps muscle; lower subcutaneous; and food intake (p<0.01, 122 (20)). At 1 week after the match, all metrics had recovered to their levels measured 1 month before the weigh-in. Certain variables that were highly sensitive to hydration recovered more rapidly: they had reached their initial levels when measured immediately after the match. CONCLUSION: Rapid weight reduction reduced the wrestlers' cross-sectional areas of muscle and fat tissues, which tended to recover through rehydration after the weigh-in. These results suggest that rapid weight reduction of wrestlers induced changes in different regions of the body.