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1.
Science ; 379(6635): 908-912, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36862771

RESUMO

Understanding the strange metallic behavior that develops at the brink of localization in quantum materials requires probing the underlying electronic charge dynamics. Using synchrotron radiation-based Mössbauer spectroscopy, we studied the charge fluctuations of the strange metal phase of ß-YbAlB4 as a function of temperature and pressure. We found that the usual single absorption peak in the Fermi-liquid regime splits into two peaks upon entering the critical regime. We interpret this spectrum as a single nuclear transition, modulated by nearby electronic valence fluctuations whose long time scales are further enhanced by the formation of charged polarons. These critical charge fluctuations may prove to be a distinct signature of strange metals.

2.
J Vet Diagn Invest ; 34(4): 668-673, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35477373

RESUMO

A 5-y-old female bottlenose dolphin (Tursiops truncatus) from an aquarium in Japan had clinical signs of anorexia, vomiting, and bradykinesia. Enrofloxacin and lactated Ringer solution were administered for treatment of bacterial infection and for rehydration. Elevations of creatine kinase and aspartate aminotransferase activities were detected on day 4 of treatment, indicating that rhabdomyolysis had developed on day 3. On day 5, serum creatinine and urea concentrations increased and remained high throughout the remaining treatment; the dolphin died on day 16. Postmortem examination revealed massive necrosis of the longissimus dorsi muscles. Histologic examination revealed extensive necrosis of skeletal myofibers, multifocal renal tubular necrosis with intratubular casts and crystals, and suppurative bronchopneumonia. The renal casts labeled positively with anti-myoglobin antibody; expression of aquaporin-1 was decreased in renal tubules compared to normal kidney tissue. To our knowledge, this description of clinicopathologic findings of rhabdomyolysis leading to acute kidney injury with concomitant crystalline nephropathy has not been reported previously in a bottlenose dolphin.


Assuntos
Injúria Renal Aguda , Golfinho Nariz-de-Garrafa , Nefrose , Rabdomiólise , Injúria Renal Aguda/veterinária , Animais , Feminino , Necrose/veterinária , Nefrose/complicações , Nefrose/veterinária , Rabdomiólise/complicações , Rabdomiólise/diagnóstico , Rabdomiólise/veterinária
3.
Biol Pharm Bull ; 43(5): 904-907, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32378566

RESUMO

CYP2D6 is an important drug-metabolizing enzyme involved in the metabolism of 20-25% of commonly prescribed drugs. Genetic polymorphism of CYP has clinically significant modifications in patients' drug-metabolizing capacities. Since gene copy number variation (CNV) and single nucleotide polymorphism (SNP) frequently occur in the CYP2D6 gene, which the activity of CYP2D6 particularly depend on the genetic factors. This study aimed to investigate the frequencies of CYP2D6 genotypes in a Japanese female subject of 216 healthy volunteers. The volunteers were genotyped for CNV Exon 9 and four CYP2D6 genetic variants (*2, *5, *10, *14, *41) performed by TaqMan® genotyping assays. The CNV allele frequencies were 82.9% for two copies, 11.6% for one copy, 4.6% for three copies and 0.9% for zero copy, respectively. The frequencies of CYP2D6*1, *2, *5, *10, *14, and *41 were 38.7, 16.7, 6.3, 34.7, 0.2, and 1.2%, respectively. CYP2D6*5 and *14 were the major defective alleles. However, this genotyping is labor intensive, time consuming, and costly. We report an optimized novel protocol for the determination of CNV and SNP in CYP2D6 gene by real-time quantitative PCR. This can lower the cost and accurately determine CNV and SNP in the CYP2D6 gene with a higher output and enabling reliable estimates of disease prediction in large epidemiological samples.


Assuntos
Povo Asiático/genética , Citocromo P-450 CYP2D6/genética , Genótipo , Feminino , Frequência do Gene , Humanos , Polimorfismo de Nucleotídeo Único , Reação em Cadeia da Polimerase em Tempo Real
4.
Yakugaku Zasshi ; 139(8): 1111-1119, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31366848

RESUMO

A new single nucleotide polymorphisms (SNP) genotyping method has been developed and validated using biological specimens directly as templates for TaqMan PCR without general DNA extraction and purification procedure from dried saliva samples attached on water-soluble papers. This new method can set up at ease and complete PCR analysis including data interpretation in under two hours with additional advantages of application for large-scale clinical research, diagnostics, and epidemiological studies at low cost. Specifically, SNP genotyping of alcohol metabolism-related genes ADH1B (rs1229984) and ALDH2 (rs671) were demonstrated by TaqMan PCR assay using dried saliva samples in the present investigation. In this protocol, by simplifying experimental operations and improving efficiency, omitting and simplifying the time and laborious DNA purification process, it is possible to shorten the experiment time and reduce the risk of human error such as contamination. Furthermore it became possible with great cost reduction. We succeeded in dramatically improving the judgment rate and accuracy of SNP genotyping by the master mix reagent for commercial available real-time TaqMan PCR. Moreover, it becomes possible to stably introduce template DNA into the reaction system, and it will be possible to apply it to copy number variation (CNV) by TaqMan probe method. The SNP analysis process using this optimized water-soluble paper will be applied to gene polymorphism analysis of drug metabolizing enzyme gene CYP, etc., to help efforts to realize personalized medicine.


Assuntos
Álcool Desidrogenase/genética , Álcoois/metabolismo , Aldeído-Desidrogenase Mitocondrial/genética , Genótipo , Técnicas de Genotipagem/métodos , Polimorfismo de Nucleotídeo Único/genética , Variações do Número de Cópias de DNA , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Saliva
5.
Biol Pharm Bull ; 42(8): 1345-1349, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366869

RESUMO

DNA extraction and purification have been generally considered to be required for PCR assay. We demonstrated a new protocol using biological specimens directly as templates for real-time PCR with melting curve analysis. We confirmed the melting curve analysis was particularly suitable for the identification of the insertion/deletion (Ins/Del) polymorphism of the angiotensin-converting enzyme (ACE) gene. The new protocol we developed can be set up using simple and complete PCR analysis including data interpretation in under four hours with additional advantages of application for large-scale clinical research, diagnostics, and epidemiological studies at low cost.


Assuntos
Técnicas de Genotipagem/métodos , Peptidil Dipeptidase A/genética , Povo Asiático , Feminino , Genótipo , Humanos , Mutação INDEL , Polimorfismo Genético , Reação em Cadeia da Polimerase em Tempo Real , Saliva/química
6.
Prog Orthod ; 20(1): 2, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30637515

RESUMO

BACKGROUND: Anatomical textbooks mention that the contact between the pterygoid process and the palatine's pyramidal process is not a "suture" but "conjugation.".The aim was to evaluate the maxillofacial morphological factor responding most to the orthopedic force of facial mask treatment, using the structural superimposition analysis. METHODS: Thirty-one girls with Angle Class III malocclusion treated using a facial mask (FM group) and 11 girls with pseudo-Class III malocclusion (pseudo-III group) were examined. Lateral cephalograms at pre- and posttreatment were analyzed to evaluate maxillofacial changes. Cephalometric structural superimposition analysis originating with Björk and Skieller was also performed. RESULTS: In the FM group, a multiple linear regression model showed that maxillary sutural growth was significantly associated with counter-clockwise rotation of the maxilla and treatment changes in the anteroposterior distance from the pterygomaxillary fissure to the maxillary anterior alveolus, not changes in the distance from the nasion to the maxillary anterior alveolus. CONCLUSIONS: Structural superimposition analysis showed that counter-clockwise rotation of the maxilla and changes in the distance from the pterygomaxillary fissure to the maxillary anterior alveolus responded most to the orthopedic force of facial mask treatment. The analysis implicated that the pterygoid fissure-palatine's pyramidal process conjugation responds most to facial mask treatment among maxillofacial sutures and conjugation, and that the difference in the response induces maxillary counter-clockwise rotation.


Assuntos
Maxila/crescimento & desenvolvimento , Anormalidades Maxilofaciais/etiologia , Cefalometria , Criança , Feminino , Humanos , Má Oclusão Classe III de Angle/diagnóstico , Máscaras , Ortodontia , Rotação
7.
Cranio ; 37(4): 264-271, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29359644

RESUMO

Objective: To evaluate whether osseous changes of the temporomandibular joint (TMJ) condyle affect backward rotation of the mandibular ramus in Angle Class II orthodontic patients with idiopathic condylar resorption (ICR). Methods: Twenty Japanese women with Class II malocclusion with ICR (ICR group) and 24 women with Class II malocclusion without ICR (non-ICR group) were examined. Pre-treatment panoramic radiographs were used to measure condylar ratios. Pre-treatment lateral cephalograms were used to evaluate maxillofacial morphology. Results: The ICR group had a significantly smaller condylar ratio, greater backward rotation of the ramus, less labially inclined upper incisors, and a steeper occlusal plane. The increased backward rotation of the ramus in the ICR group was significantly associated with a smaller condylar ratio. Conclusion: Angle Class II patients with ICR had shorter condylar height attributable to osseous changes of the TMJ condyle, and the shorter condylar height may affect subsequent backward rotation of the ramus.


Assuntos
Reabsorção Óssea/patologia , Reabsorção Óssea/fisiopatologia , Má Oclusão Classe II de Angle/patologia , Má Oclusão Classe II de Angle/fisiopatologia , Côndilo Mandibular/patologia , Côndilo Mandibular/fisiopatologia , Rotação , Transtornos da Articulação Temporomandibular/patologia , Transtornos da Articulação Temporomandibular/fisiopatologia , Articulação Temporomandibular/patologia , Articulação Temporomandibular/fisiopatologia , Adulto , Reabsorção Óssea/diagnóstico por imagem , Feminino , Humanos , Má Oclusão Classe II de Angle/diagnóstico por imagem , Côndilo Mandibular/diagnóstico por imagem , Pessoa de Meia-Idade , Radiografia Panorâmica , Articulação Temporomandibular/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Adulto Jovem
8.
J Phys Condens Matter ; 26(29): 295702, 2014 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-24957489

RESUMO

We have investigated the electronic states of single-crystal CaFe2As2 under hydrostatic pressure using (57)Fe Mössbauer spectroscopy and magnetization measurements. The center shift and the quadrupole splitting were refined from observed (57)Fe Mössbauer spectra using the single-crystalline sample under pressure at room temperature. A discontinuous decrease in the pressure dependence of the refined center shift was observed at 0.33 GPa without any anomaly in the pressure dependence of the refined quadrupole splitting, indicating a purely electronic state change in CaFe2As2 with a tetragonal structure. Such a change is shown to be reflected in the peak-like anomalies observed in the pressure dependences of the magnetic susceptibility at 0.26 GPa above 150 K. Our results reveal that this pressure-induced electronic state change suppresses the tetragonal-to-orthorhombic structural phase transition accompanied by an antiferromagnetic ordering. We further observed superconductivity in CaFe2As2 below ∼ 8 K around 0.33 GPa although our sample was not in a single phase at this pressure. These findings suggest that the electronic state change observed in CaFe2As2 with the tetragonal structure is relevant to the appearance of the pressure-induced superconductivity in AFe2As2.

9.
J Phys Condens Matter ; 25(2): 022201, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23209081

RESUMO

The electronic and vibrational properties of EuFe(2)As(2) in the tetragonal phase between 0 and 5 GPa have been investigated using (57)Fe Mössbauer spectroscopy and (57)Fe nuclear resonance inelastic scattering, respectively. We find a discontinuous increase of the center shift around 2.3 GPa, reflecting a change of the electronic state of Fe, and above 2.5 GPa a softening of the optical phonon modes associated with an increase of the relative volume of the FeAs(4) tetrahedron in the unit cell. Our findings reveal that an effective As-As hybridization along the c axis appears at approximately 2.3 GPa in the tetragonal phase of EuFe(2)As(2), along with a change in the electronic state of Fe, causing bulk superconductivity to appear at a low temperature. Consequently, the change in the electronic state of the Fe atom and the effective As-As hybridization play key roles in the pressure-induced superconductivity in the tetragonal phase of AFe(2)As(2).


Assuntos
Arsênio/química , Európio/química , Ferro/química , Sítios de Ligação , Transporte de Elétrons , Teste de Materiais , Pressão
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