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1.
Nat Commun ; 14(1): 7651, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030606

RESUMO

Owing to their high magnon frequencies, antiferromagnets are key materials for future high-speed spintronics. Picosecond switching of antiferromagnetic spin systems has been viewed a milestone for decades and pursued only by using ultrafast external perturbations. Here, we show that picosecond spin switching occurs spontaneously due to thermal fluctuations in the antiferromagnetic orthoferrite Sm0.7Er0.3FeO3. By analysing the correlation between the pulse-to-pulse polarisation fluctuations of two femtosecond optical probes, we extract the autocorrelation of incoherent magnon fluctuations. We observe a strong enhancement of the magnon fluctuation amplitude and the coherence time around the critical temperature of the spin reorientation transition. The spectrum shows two distinct features, one corresponding to the quasi-ferromagnetic mode and another one which has not been previously reported in pump-probe experiments. Comparison to a stochastic spin dynamics simulation reveals this new mode as smoking gun of ultrafast spontaneous spin switching within the double-well anisotropy potential.

2.
Oper Dent ; 48(5): 483-489, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37503684

RESUMO

Direct composite restorations are accepted as a treatment option for microdontia, which is a relatively prevalent condition that poses esthetic concerns. While free-hand composite placement is technique-sensitive and time-consuming, the resin composite injection technique is more straightforward and predictable. A fully digital workflow has been recently introduced, but the 3D-printed resin index is rigid and challenged by undercuts, as opposed to the silicone index. This case report presents a flexible 3D-printed resin index, which can accurately transfer the digitally simulated functional and esthetic form to the final restoration. In addition, a rigid stabilization holder was designed to stabilize the flexible index.


Assuntos
Resinas Compostas , Estética Dentária , Humanos , Fluxo de Trabalho , Resinas Compostas/uso terapêutico , Silicones , Impressão Tridimensional
3.
Biochem Biophys Rep ; 35: 101514, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37521371

RESUMO

Impaired microcirculation can cause lymphatic leakage which leads to a chronic swelling in the tissues of the body. However, no successful treatment gives any protection against lymphedema due to the lack of well-revealed pathophysiology of secondary lymphedema. Binary image of laminin immunohistochemical expression revealed that distribution of laminin expression localized during surgically induced lymphedema. 67 kDa laminin receptor (67LR) mRNA expression showed a peak at during lymphedema exacerbation. Since the response of 67LR molecules may affect the prevention of inflammation and edema, here we have hypothesized that 67LR ligand of YIGSR peptide could permit reconstructive environment for amelioration of lymphedema and evaluated the effect of YIGSR in a mouse tail model of lymphedema. Indeed, intra-abdominal injections of YIGSR for the first 3 days after inducing lymphedema in the mouse tail model reduced the tail lymphedema on day 14 by 27% (P = 0.035). Histology showed that YIGSR treatment protected lymphedema impairment in epidermis and dermis, and it also inhibited the expansion of intercellular spaces and enhanced especially cell adhesion in the basement membrane as revealed by transmission electron microscopy. Interestingly, the treatment also reduced the local expression of transforming growth factor (TGF)ß. Further elucidation of the mechanisms of 67LR-facilitated lymphangiogenesis contributes to find potential targets for the treatment of lymphedema.

4.
Science ; 373(6559): 1122-1125, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34516833

RESUMO

Nematicity is ubiquitous in the electronic phases of iron-based superconductors. The order parameter that characterizes the nematic phase has been investigated in momentum space, but its real-space arrangement remains largely unexplored. We use linear dichroism (LD) in a low-temperature laser­photoemission electron microscope to map out the nematic order parameter of nonmagentic FeSe and antiferromagnetic BaFe2(As0.87P0.13)2. In contrast to structural domains, which have atomic-scale domain walls, the LD patterns in both materials show peculiar sinusoidal waves of electronic nematicity with wavelengths more than 1000 times as long as the unit cell. Our findings put strong constraints on the theoretical investigation of electronic nematicity.

5.
Eur J Neurol ; 28(2): 389-400, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33035386

RESUMO

BACKGROUND AND PURPOSE: Protein tyrosine phosphatase receptor type Q (PTPRQ) was extracted from the cerebrospinal fluid (CSF) of patients with probable idiopathic normal-pressure hydrocephalus (iNPH) by proteome analysis. We aimed to assess the feasibility of using CSF PTPRQ concentrations for the additional diagnostic criterion of iNPH in Japanese and Finnish populations. METHODS: We compared PTPRQ concentrations among patients with probable iNPH and neurologically healthy individuals (normal control [NC] group), patients with normal-pressure hydrocephalus (NPH) of acquired and congenital/developmental aetiologies, patients with Alzheimer's disease and patients with Parkinson's disease in a Japanese analysis cohort. A corresponding iNPH group and NC group in a Finnish cohort was used for validation. Patients in the Finnish cohort who underwent biopsy were classified into two groups based on amyloid and/or tau deposition. We measured PTPRQ expression levels in autopsied brain specimens of iNPH patients and the NC group. RESULTS: Cerebrospinal fluid PTPRQ concentrations in the patients with NPH of idiopathic, acquired and congenital/developmental aetiologies were significantly higher than those in the NC group and those with Parkinson's disease, but iNPH showed no significant differences when compared with those in the Alzheimer's disease group. For the patients with iNPH, the area under the receiver-operating characteristic curve was 0.860 in the Japanese iNPH and 0.849 in the Finnish iNPH cohorts. Immunostaining and in situ hybridization revealed PTPRQ expression in the ependymal cells and choroid plexus. It is highly possible that the elevated PTPRQ levels in the CSF are related to ependymal dysfunction from ventricular expansion. CONCLUSIONS: Cerebrospinal fluid PTPRQ levels indicated the validity of this assay for auxiliary diagnosis of adult chronic hydrocephalus.


Assuntos
Doença de Alzheimer , Hidrocefalia de Pressão Normal , Adulto , Peptídeos beta-Amiloides , Biomarcadores , Humanos , Proteínas Tirosina Fosfatases , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores
6.
Rev Sci Instrum ; 91(12): 125109, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33379944

RESUMO

Positron annihilation lifetime spectroscopy (PALS), which is recognized as one of the major analytical methods of positron annihilation spectroscopy, can directly detect information related to the size of vacancy-type defects from lifetime values. PALS measurements performed under high background radiation have been previously reported. It is well known that coincidence techniques such as age-momentum correlation (AMOC) measurements are effective for the background reduction, but count rates decline significantly. In this study, a preliminary experiment was performed to reduce the influence of the background radiation without the coincidence technique in the pulsing system of the Kyoto University research Reactor (KUR) slow positron beamline. This experiment involved the introduction of a gate circuit for the background radiation discrimination using a dynode signal from a single scintillation detector (photomultiplier). After introducing the gate circuit, the time resolution and the lifetime value of Kapton were 308 ps and 388 ± 3 ps, respectively, with count rates of ∼400 counts/s at a KUR 5 MW operation. In the AMOC measurement, the time resolution and the lifetime value of Kapton were 297 ps and 380 ± 7 ps, respectively, with count rates of ∼40 counts/s at a KUR 5 MW operation. When the single detector with the gate circuit was used, the count rate was ∼1 order of magnitude higher than those of the AMOC measurements, while the time resolutions of the two methods were comparable.

7.
Oper Dent ; 45(5): 556-566, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32243250

RESUMO

CLINICAL RELEVANCE: The degree of conversion of contemporary universal adhesives positively correlates with the bond strength to dentin. The correlation is more marked after thermocycling, suggesting that a high degree of conversion is required for long-term dentin bonding durability. SUMMARY: Purpose: The objectives of this study were to evaluate the micro-tensile bond strength (µTBS) of five contemporary universal adhesives to dentin after 24 hours and thermocycling (TC), to measure their degrees of conversion (DC) and to test the correlation between µTBS and DC.Methods and Materials: Four commercially available universal adhesives, Prime&Bond universal (PBU), Ecosite Bond (EB), G-Premio Bond (GPB), and Clearfil Universal Bond Quick (UBQ), and one experimental adhesive, UBQ without an amide monomer (UBQ-A), were used in this study. For the µTBS test, midcoronal dentin of 50 human molars was exposed, ground using 600-grit SiC paper, and the adhesives were applied according to the manufacturers' instructions. After resin-composite buildup and 24-hour water storage, one-half of the specimens were subjected to 15,000 thermal cycles. The specimens were sectioned into beams and stressed in tension at a crosshead speed of 1 mm/min until failure. The DC of adhesives applied to dentin was evaluated using attenuated total reflectance Fourier-transform infrared spectroscopy immediately after light-curing. All data were statistically analyzed at a significance level of 0.05.Results: The highest µTBSs were obtained with UBQ, UBQ-A, and PBU, which were not significantly different from each other both after 24 hours and TC. The µTBS of GPB was lower compared with the aforementioned adhesives, but significantly only after TC, and the lowest µTBSs were obtained with EB. TC did not affect the µTBSs of UBQ, UBQ-A, and PBU significantly, but a significant decrease was observed with GPB and EB. The highest DC was obtained with PBU and UBQ, followed by 2-hydroxyethyl methacrylate-rich adhesives UBQ-A and EB, which exhibited significantly lower DCs. The DC of GPB could not be determined because the reference peak at 1608 cm-1 was not detected in its spectra. A significant positive correlation was shown between µTBS and DC after 24 hours (r=0.716) and TC (r=0.856).Conclusion: µTBS and DC were positively correlated, more markedly after TC, which suggests that DC may be an important factor for bond durability.


Assuntos
Colagem Dentária , Adesivos Dentinários , Adesivos , Resinas Compostas , Cimentos Dentários , Dentina , Humanos , Teste de Materiais , Cimentos de Resina , Resistência à Tração
8.
Osteoarthritis Cartilage ; 27(10): 1501-1507, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31233787

RESUMO

OBJECTIVE: To clarify the genetic mechanisms underlying intervertebral disc degeneration (IDD), we examined the associations between single-nucleotide polymorphisms (SNPs) and indicated as coefficient of interaction term (IDD) in a general population in Japan. METHODS: This was a cross-sectional study. In 1,605 participants, C2-3 to L5/S1 in the total spine magnetic resonance imaging (MRI) were evaluated using the Pfirrmann's scoring system. Disc scores of 4 and 5 were defined as IDD. Eight SNPs in eight genes associated with IDD were examined at each disc level, considering the non-genetic risk factors of age, sex, and body mass index (BMI). RESULTS: The highest odds ratio was found for rs9406328 in the THBS2 gene at disc level T12-L1 (OR 1.27, 95%CI 1.05 to 1.53), and this association was strengthened after adjustment for age using logistic regression (OR 1.37, 95%CI 1.12 to 1.67). Among participants aged <50 years and 50-59, the average IDD score in those with 2 risk alleles of rs9406328 was markedly higher than in those with 0 or 1 risk allele, and the difference is much wider than the elderly participants. It indicates the genetic effect of rs9406328 is stronger in the younger age groups. Finally, multiple linear regression analyses of the association between rs9406328 and IDD, adjusted for age, sex, and BMI at each disc level, showed a statistical interaction between age and the number of risk alleles at C7-T1, T3-4 and T4-T5 as well as T12-L1. CONCLUSION: CONCLUSION: The association between rs9406328 in THBS2 and IDD was replicated. The contributions of genetic and environmental factors to IDD differed by disc level.


Assuntos
Degeneração do Disco Intervertebral/genética , Polimorfismo de Nucleotídeo Único , Trombospondinas/genética , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade
9.
Opt Express ; 26(12): 15247-15254, 2018 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-30114774

RESUMO

The emission with a bandwidth of 1.5 terahertz based on the spin current in the ferromagnetic heterostructure Co/Pt is demonstrated. The spin transient launched by the NIR femtosecond laser pulse in the Co/Pt is converted into the in-plane charge current due to the inverse spin Hall effect, which gives rise to the terahertz emission towards free space. The dependence of the terahertz emission on the Pt-layer thickness is investigated. To optimize the geometry structure of the new type of emitter, we developed the theoretical model by carefully analyzing the spin transport. Our model reveals the importance to take into account the interfacial spin loss. It can be used to analyze more complex heterostructures.

10.
J Periodontal Res ; 53(3): 446-456, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29516504

RESUMO

BACKGROUND AND OBJECTIVES: Previous reports suggest that several serum biomarkers play roles in the pathogenesis, inflammatory response, and oxidative stress in periodontitis caused by bacterial infections, linking chronic periodontitis to atherosclerotic vascular disease (ASVD). The aim of this preliminary study was to investigate, in a Japanese cross-sectional community survey, potential serum biomarkers of periodontitis that are associated with ASVD and chronic periodontitis. MATERIAL AND METHODS: The study cohort included a total of 108 male subjects who underwent annual health examinations. Serum biomarkers (high-sensitivity C-reactive protein [hs-CRP], proprotein convertase subtilisin/kexin type 9 [PCSK9], interleukin-6, tumor necrosis factor-α, soluble CD14, myeloperoxidase, matrix metalloproteinase-3, adiponectin, total bilirubin [TBIL], and serum lipids) were analyzed to determine their association (if any) with periodontal parameters. Aortic stiffness was evaluated using the brachial-ankle aortic pulse wave velocity (PWV) index and the cardio-ankle vascular index (CAVI). RESULTS: The concentrations of PCSK9 and hs-CRP were increased (P = .001 and .042, respectively), and the concentration of TBIL was decreased (P = .046), in subjects with periodontal disease (determined as a probing depth of ≥4 mm in at least one site) compared with periodontally healthy subjects. The ratio of low-density lipoprotein cholesterol (LDL-C) to high-density lipoprotein cholesterol and the concentrations of triglycerides, remnant-like particles-cholesterol, and oxidized LDL were elevated in subjects with periodontal disease compared with periodontally healthy subjects (P = .038, .007, .002, and .049, respectively). Multivariate regression analyses indicated that the number of sites with a pocket depth of ≥4 mm was associated with the concentration of PCSK9 and inversely associated with the concentration of TBIL independently (standardized ß = .243, P = .040; standardized ß = -.443, P = .0002; respectively). Analysis of receiver operating characteristic curves of PCSK9 indicated moderate accuracy for predicting the presence of disease sites (probing depth ≥ 4 mm) (area under the curve = 0.740). No significance in the values of PWV and CAVI was observed between subjects with periodontal disease and periodontally healthy subjects. CONCLUSION: In Japanese male subjects, the concentrations of serum PCSK9 and TBIL were correlated with periodontal parameters. Moreover, PCSK9 could be a candidate biomarker for diagnosing chronic periodontitis, and may also have potential to evaluate the risk for periodontitis to cause ASVD. Longitudinal studies of larger populations are necessary to confirm the exact association of periodontitis with increased serum PCSK9 and decreased TBIL.


Assuntos
Bilirrubina/sangue , Periodontite Crônica/sangue , Pró-Proteína Convertase 9/sangue , Adiponectina/sangue , Adulto , Povo Asiático , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Periodontite Crônica/diagnóstico , Periodontite Crônica/enzimologia , Estudos de Coortes , Estudos Transversais , Humanos , Interleucina-6/sangue , Japão , Receptores de Lipopolissacarídeos/sangue , Lipoproteínas/sangue , Estudos Longitudinais , Masculino , Metaloproteinase 3 da Matriz/sangue , Pessoa de Meia-Idade , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangue
11.
Sci Rep ; 8(1): 2169, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29391431

RESUMO

High-temperature superconductivity in iron-pnictides/chalcogenides arises in balance with several electronic and lattice instabilities. Beside the antiferromagnetic order, the orbital anisotropy between Fe 3d xz and 3d yz occurs near the orthorhombic structural transition in several parent compounds. However, the extent of the survival of orbital anisotropy against the ion-substitution remains to be established. Here we report the composition (x) and temperature (T) dependences of the orbital anisotropy in the electronic structure of a BaFe2(As1-xP x )2 system by using angle-resolved photoemission spectroscopy. In the low-x regime, the orbital anisotropy starts to evolve on cooling from high temperatures above both antiferromagnetic and orthorhombic transitions. By increasing x, it is gradually suppressed and survives in the optimally doped regime. We find that the in-plane orbital anisotropy persists in a large area of the nonmagnetic phase, including the superconducting dome. These results suggest that the rotational symmetry-broken electronic state acts as the stage for superconductivity in BaFe2(As1-xP x )2.

12.
Acta Neurol Scand ; 136(1): 31-40, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27666559

RESUMO

OBJECTIVES: To investigate clinical characteristics of ipsilateral hemiparesis in ischemic stroke patients. MATERIALS AND METHODS: Patients with acute ischemic stroke were prospectively examined. Ipsilateral hemiparesis was defined as hemiparesis ipsilateral to recent stroke lesions. Patients with ipsilateral hemiparesis were examined with functional neuroimaging studies including transcranial magnetic stimulation (TMS) and functional MRI. RESULTS: Of 8360 patients, ipsilateral hemiparesis was detected in 14 patients (0.17%, mean age 71±6 years, eight men). Lesions responsible for the recent strokes were located in the frontal cortex in three patients, corona radiata in seven, internal capsule in one, and pons in three. These lesions were located along the typical route of the corticospinal tract in all but one patient. Thirteen patients also had a past history of stroke contralateral to the recent lesions; 12 of these had motor deficits contralateral to past stroke lesions. During TMS, ipsilateral magnetic evoked potentials were evoked in two of seven patients and contralateral potentials were evoked in all seven. Functional MRI activated cerebral hemispheres ipsilaterally in eight of nine patients and contralaterally in all nine. CONCLUSIONS: Most patients with ipsilateral hemiparesis had a past history of stroke contralateral to the recent one, resulting in motor deficits contralateral to the earlier lesions. Moreover, functional neuroimaging findings indicated an active crossed corticospinal tract in all of the examined patients. Both findings suggest the contribution of the uncrossed corticospinal tract contralateral to stroke lesions as a post-stroke compensatory motor system.


Assuntos
Lateralidade Funcional , Paresia/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Potencial Evocado Motor , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Paresia/diagnóstico por imagem , Tratos Piramidais/fisiopatologia , Acidente Vascular Cerebral/diagnóstico por imagem , Estimulação Magnética Transcraniana
13.
Nat Mater ; 15(12): 1233-1236, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27525569

RESUMO

The superconducting transition temperature (TC) in a FeSe monolayer on SrTiO3 is enhanced up to 100 K (refs ,,,). High TC is also found in bulk iron chalcogenides with similar electronic structure to that of monolayer FeSe, which suggests that higher TC may be achieved through electron doping, pushing the Fermi surface (FS) topology towards leaving only electron pockets. Such an observation, however, has been limited to chalcogenides, and is in contrast to the iron pnictides, for which the maximum TC is achieved with both hole and electron pockets forming considerable FS nesting instability. Here, we report angle-resolved photoemission characterization revealing a monotonic increase of TC from 24 to 41.5 K upon surface doping on optimally doped Ba(Fe1-xCox)2As2. The doping changes the overall FS topology towards that of chalcogenides through a rigid downward band shift. Our findings suggest that higher electron doping and concomitant changes in FS topology are favourable conditions for the superconductivity, not only for iron chalcogenides, but also for iron pnictides.

14.
Clin Genet ; 90(6): 526-535, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27434533

RESUMO

Joubert syndrome (JS) is rare recessive disorders characterized by the combination of hypoplasia/aplasia of the cerebellar vermis, thickened and elongated superior cerebellar peduncles, and a deep interpeduncular fossa which is defined by neuroimaging and is termed the 'molar tooth sign'. JS is genetically highly heterogeneous, with at least 29 disease genes being involved. To further understand the genetic causes of JS, we performed whole-exome sequencing in 24 newly recruited JS families. Together with six previously reported families, we identified causative mutations in 25 out of 30 (24 + 6) families (83.3%). We identified eight mutated genes in 27 (21 + 6) Japanese families, TMEM67 (7/27, 25.9%) and CEP290 (6/27, 22.2%) were the most commonly mutated. Interestingly, 9 of 12 CEP290 disease alleles were c.6012-12T>A (75.0%), an allele that has not been reported in non-Japanese populations. Therefore c.6012-12T>A is a common allele in the Japanese population. Importantly, one Japanese and one Omani families carried compound biallelic mutations in two distinct genes (TMEM67/RPGRIP1L and TMEM138/BBS1, respectively). BBS1 is the causative gene in Bardet-Biedl syndrome. These concomitant mutations led to severe and/or complex clinical features in the patients, suggesting combined effects of different mutant genes.


Assuntos
Anormalidades Múltiplas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Antígenos de Neoplasias/genética , Cerebelo/anormalidades , Anormalidades do Olho/genética , Doenças Renais Císticas/genética , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/genética , Retina/anormalidades , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/fisiopatologia , Alelos , Proteínas de Ciclo Celular , Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Proteínas do Citoesqueleto , Anormalidades do Olho/diagnóstico por imagem , Anormalidades do Olho/epidemiologia , Anormalidades do Olho/fisiopatologia , Feminino , Heterogeneidade Genética , Predisposição Genética para Doença , Humanos , Japão/epidemiologia , Doenças Renais Císticas/diagnóstico por imagem , Doenças Renais Císticas/epidemiologia , Doenças Renais Císticas/fisiopatologia , Masculino , Mutação , Omã/epidemiologia , Linhagem , Retina/diagnóstico por imagem , Retina/fisiopatologia
15.
Sci Rep ; 6: 27783, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27301665

RESUMO

The effects of isotropic artifical defects, introduced via fast neutron (E > 0.1 MeV) irradiation, on the physical properties of differently (Co, P and K) doped BaFe2As2 superconducting single crystals were studied. The Co- and P-doped single crystals showed a second peak in the magnetization curve (fishtail effect) in the pristine state. Significant variations in the radiation-induced changes in the critical current density Jc were observed in the different types of crystal, while the irreversibility fields did not change remarkably. The highest Jcs were obtained for the K-doped crystal, exceeding 3 × 10(10) Am(-2) (T = 5 K, B = 4 T) and remaining above 8.5 × 10(9) Am(-2) at 30 K and 1 T. The pinning force was analyzed to compare the pinning mechanisms of the individual samples. While distinct differences were found before the irradiation, the same pinning behavior prevails afterwards. The pinning efficiency η = Jc/Jd was estimated from the depairing current density Jd. η was similar in all irradiated crystals and comparable to the value in neutron irradiated cuprates, suggesting that the huge critical current densities measured in the irradiated K-doped crystal are due to its large depairing current density, making this compound the most promising for applications.

16.
Acta Biomater ; 33: 235-41, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26827779

RESUMO

During dentin bonding with etch-and-rinse adhesive systems, phosphoric acid etching of mineralized dentin solubilizes the mineral crystallites and replaces them with bound and unbound water. During the infiltration phase of dentin bonding, solvated adhesive resin comonomers are supposed to replace all of the unbound collagen water and polymerize into copolymers. A recently published review suggested that dental monomers are too large to enter and displace water from tightly-packed collagen molecules. Conversely, recent work from the authors' laboratory demonstrated that HEMA and TEGDMA freely equilibrate with water-saturated dentin matrices. However, because adhesive blends are solvated in organic solvents, those solvents may remove enough free water to allow collagen molecules to come close enough to exclude adhesive monomer permeation. The present study analyzed the size-exclusion characteristics of dentin collagen, using a gel permeation-like column chromatography technique, filled with dentin powder instead of Sephadex beads as the stationary phase. The elution volumes of different sized test molecules, including adhesive resin monomers, studied in both water-saturated dentin, and again in ethanol-dehydrated dentin powder, showed that adhesive resin monomers can freely diffuse into both hydrated and dehydrated collagen molecules. Under these in vitro conditions, all free and some of the loosely-bound water seems to have been removed by ethanol. These results validate the concept that adhesive resin monomers can permeate tightly-bound water in ethanol-saturated collagen molecules during infiltration by etch-and-rinse adhesives. STATEMENT OF SIGNIFICANCE: It has been reported that collagen molecules in dentin matrices are packed too close together to allow permeation of adhesive monomers between them. Resin infiltration, in this view, would be limited to extrafibrillar spaces. Our work suggests that monomers equilibrate with collagen water in both water and ethanol-saturated dentin matrices.


Assuntos
Cromatografia em Gel , Colágeno Tipo I/química , Adesivos Dentinários/química , Dentina/química , Etanol/farmacologia , Cimentos de Resina/química , Animais , Soluções Tampão , Bovinos , Solubilidade , Desmineralização do Dente
17.
Hum Reprod ; 31(4): 774-81, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26908843

RESUMO

STUDY QUESTION: How do the temperature and duration of storage affect ovaries during transportation? SUMMARY ANSWER: Fertility is reduced with the extension of the storage duration. WHAT IS KNOWN ALREADY: Live birth has been reported after ovarian transport overnight on ice before freezing ovarian tissue, but there have been no basic investigations of ovarian storage conditions focused on fertility. There are no guidelines on optimal ovarian storage conditions and the maximum storage time during transportation. STUDY DESIGN, SIZE AND DURATION: Experiments were performed using C57BL/6J mice. Ovaries of 4-week-old mice were harvested, stored at 4, 14, 37 °C or room temperature (RT) for 24 h, and subjected to histological examination. Next, ovaries were stored at 4 °C for 4, 8 or 24 h and subjected to histological examination. Then orthotopic transplantation of ovaries, stored at 4 °C for 4, 8 or 24 h, was performed in 6-week-old C57BL/6J mice, and fertility was assessed by in vitro fertilization and embryo transfer. Freshly harvested ovaries were used as controls for comparison with ovaries stored under the above-mentioned conditions and experiments were repeated at least three times. PARTICIPANTS/MATERIALS, SETTING AND METHODS: In experiments on the ovarian storage temperature, haematoxylin-eosin (HE) staining was performed for histological examination. In experiments on the storage duration, HE staining, the terminal deoxynucleotidyl transferase dUTP nick end labelling assay, Ki-67 staining and electron microscopy were performed, and the numbers of follicles were counted. Fertility was assessed from the number of oocytes, and the rates of fertilization, embryo development, implantation and live birth. MAIN RESULTS AND THE ROLE OF CHANCE: Histological changes were minimal after storage of ovaries at 4 °C for up to 24 h. At 4 °C, there were no significant changes in the number of MII oocytes, fertilization rate or blastocyst development rate with storage up to 24 h. The implantation rate was 82.7 ± 17.3% in the control group, while it was 82.2 ± 7.7, 14.6 ± 14.6 and 4.4 ± 4.4% after storage for 4, 8 or 24 h, respectively. After 8 or 24 h of storage, the implantation rate was significantly lower in than in the control group (P< 0.05). The rate of live pups was 24.8 ± 13.2% in the control group, while it was 23.9 ± 6.6, 4.2 ± 4.2 and 4.4 ± 4.4% after storage for 4, 8 or 24 h, respectively. After 8 or 24 h of storage, the rate of live pups was significantly lower than in the control group (P< 0.05). LIMITATIONS, REASONS FOR CAUTION: Further investigations are needed in mammals with ovaries of a similar size to human ovaries, and should include the assessment of fertility following transplantation of frozen and thawed ovaries. WIDER IMPLICATION OF THE FINDINGS: The present results suggest that prolonging the ovarian storage time reduces fertility in mice. Thus, ovaries should be frozen immediately after harvesting or transported as rapidly as possible to minimize damage. To allow young cancer patients to preserve fertility, regional medical centres need adequate ovarian tissue cryopreservation techniques. STUDY FUNDING/COMPETING INTERESTS: This study supported by Department of Obstetrics and Gynecology, St. Marianna University School of Medicine. The authors have no competing interests to declare.


Assuntos
Criopreservação/veterinária , Ovário/transplante , Meios de Transporte , Animais , Cesárea/veterinária , Temperatura Baixa/efeitos adversos , Criopreservação/métodos , Transferência Embrionária/veterinária , Feminino , Fertilização in vitro/veterinária , Japão , Nascido Vivo/veterinária , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Transmissão/veterinária , Ovário/citologia , Ovário/metabolismo , Ovário/ultraestrutura , Fatores de Tempo
18.
AJNR Am J Neuroradiol ; 37(3): E26, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26721768
19.
Acta Neurol Scand ; 134(1): 49-53, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26434688

RESUMO

OBJECTIVE: We previously reported that decrement of compound muscle action potential (CMAP) by repetitive nerve stimulation (RNS) was greater in the median nerves than in the ulnar nerves of patients with amyotrophic lateral sclerosis (ALS). The aim of this study was to evaluate whether CMAP decrement by RNS is a feasible marker for the differentiation of ALS from other diseases. MATERIALS & METHODS: We performed RNS in the median and ulnar nerves of 51 patients with ALS and 40 patients with other diseases. RESULTS: The CMAP decrement was significantly greater in the median nerves of patients with ALS, compared to the disease control patients. In the median nerves of patients with ALS, CMAP decrement was significantly greater in the cervical region-onset group than in the other region-onset group. CONCLUSIONS: The finding of CMAP decrement in the median nerves can be useful for differentiating ALS patients with cervical region onset from other controls with active neuropathic diseases.


Assuntos
Potenciais de Ação/fisiologia , Esclerose Lateral Amiotrófica/diagnóstico , Adulto , Idoso , Estimulação Elétrica/métodos , Feminino , Humanos , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade
20.
AJNR Am J Neuroradiol ; 37(2): 223-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26450535

RESUMO

BACKGROUND AND PURPOSE: Because the diagnostic significance of cortical superficial siderosis for Alzheimer disease and the association between cortical superficial siderosis and the topographic distribution of cerebral microbleeds have been unclear, we investigated the association between cortical superficial siderosis and clinicoradiologic characteristics of patients with cognitive impairment. MATERIALS AND METHODS: We studied 347 patients (217 women, 130 men; mean age, 74 ± 9 years) who visited our memory clinic and underwent MR imaging (3T SWI). We analyzed the association between cortical superficial siderosis and the topographic distribution of cerebral microbleeds plus clinical characteristics including types of dementia. We used multivariate logistic regression analysis to determine the diagnostic significance of cortical superficial siderosis for Alzheimer disease. RESULTS: Twelve patients (3.5%) manifested cortical superficial siderosis. They were older (P = .026) and had strictly lobar cerebral microbleeds significantly more often than did patients without cortical superficial siderosis (50.0% versus 19.4%, P = .02); the occurrence of strictly deep and mixed cerebral microbleeds, however, did not differ in the 2 groups. Alzheimer disease was diagnosed in 162 (46.7%) patients. Of these, 8 patients (4.9%) had cortical superficial siderosis. In the multivariate logistic regression analysis for the diagnosis of Alzheimer disease, lacunar infarcts were negatively and independently associated with Alzheimer disease (P = .007). CONCLUSIONS: Although cortical superficial siderosis was associated with a strictly lobar cerebral microbleed location, it was not independently associated with Alzheimer disease in a memory clinic setting. Additional studies are required to investigate the temporal changes of these cerebral amyloid angiopathy-related MR imaging findings.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico , Hemorragia Cerebral/complicações , Transtornos Cognitivos/etiologia , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
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