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1.
Nature ; 570(7762): 484-490, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31217587

RESUMO

For centuries, the scientific discovery process has been based on systematic human observation and analysis of natural phenomena1. Today, however, automated instrumentation and large-scale data acquisition are generating datasets of such large volume and complexity as to defy conventional scientific methodology. Radically different scientific approaches are needed, and machine learning (ML) shows great promise for research fields such as materials science2-5. Given the success of ML in the analysis of synthetic data representing electronic quantum matter (EQM)6-16, the next challenge is to apply this approach to experimental data-for example, to the arrays of complex electronic-structure images17 obtained from atomic-scale visualization of EQM. Here we report the development and training of a suite of artificial neural networks (ANNs) designed to recognize different types of order hidden in such EQM image arrays. These ANNs are used to analyse an archive of experimentally derived EQM image arrays from carrier-doped copper oxide Mott insulators. In these noisy and complex data, the ANNs discover the existence of a lattice-commensurate, four-unit-cell periodic, translational-symmetry-breaking EQM state. Further, the ANNs determine that this state is unidirectional, revealing a coincident nematic EQM state. Strong-coupling theories of electronic liquid crystals18,19 are consistent with these observations.

2.
Proc Natl Acad Sci U S A ; 117(26): 14805-14811, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32546526

RESUMO

The defining characteristic of hole-doped cuprates is d-wave high temperature superconductivity. However, intense theoretical interest is now focused on whether a pair density wave state (PDW) could coexist with cuprate superconductivity [D. F. Agterberg et al., Annu. Rev. Condens. Matter Phys. 11, 231 (2020)]. Here, we use a strong-coupling mean-field theory of cuprates, to model the atomic-scale electronic structure of an eight-unit-cell periodic, d-symmetry form factor, pair density wave (PDW) state coexisting with d-wave superconductivity (DSC). From this PDW + DSC model, the atomically resolved density of Bogoliubov quasiparticle states [Formula: see text] is predicted at the terminal BiO surface of Bi2Sr2CaCu2O8 and compared with high-precision electronic visualization experiments using spectroscopic imaging scanning tunneling microscopy (STM). The PDW + DSC model predictions include the intraunit-cell structure and periodic modulations of [Formula: see text], the modulations of the coherence peak energy [Formula: see text] and the characteristics of Bogoliubov quasiparticle interference in scattering-wavevector space [Formula: see text] Consistency between all these predictions and the corresponding experiments indicates that lightly hole-doped Bi2Sr2CaCu2O8 does contain a PDW + DSC state. Moreover, in the model the PDW + DSC state becomes unstable to a pure DSC state at a critical hole density p*, with empirically equivalent phenomena occurring in the experiments. All these results are consistent with a picture in which the cuprate translational symmetry-breaking state is a PDW, the observed charge modulations are its consequence, the antinodal pseudogap is that of the PDW state, and the cuprate critical point at p* ≈ 19% occurs due to disappearance of this PDW.

3.
Nature ; 532(7599): 343-7, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27074504

RESUMO

The quantum condensate of Cooper pairs forming a superconductor was originally conceived as being translationally invariant. In theory, however, pairs can exist with finite momentum Q, thus generating a state with a spatially modulated Cooper-pair density. Such a state has been created in ultracold (6)Li gas but never observed directly in any superconductor. It is now widely hypothesized that the pseudogap phase of the copper oxide superconductors contains such a 'pair density wave' state. Here we report the use of nanometre-resolution scanned Josephson tunnelling microscopy to image Cooper pair tunnelling from a d-wave superconducting microscope tip to the condensate of the superconductor Bi2Sr2CaCu2O8+x. We demonstrate condensate visualization capabilities directly by using the Cooper-pair density variations surrounding zinc impurity atoms and at the Bi2Sr2CaCu2O8+x crystal supermodulation. Then, by using Fourier analysis of scanned Josephson tunnelling images, we discover the direct signature of a Cooper-pair density modulation at wavevectors QP ≈ (0.25, 0)2π/a0 and (0, 0.25)2π/a0 in Bi2Sr2CaCu2O8+x. The amplitude of these modulations is about five per cent of the background condensate density and their form factor exhibits primarily s or s' symmetry. This phenomenology is consistent with Ginzburg-Landau theory when a charge density wave with d-symmetry form factor and wavevector QC = QP coexists with a d-symmetry superconductor; it is also predicted by several contemporary microscopic theories for the pseudogap phase.

4.
Lett Appl Microbiol ; 74(3): 377-384, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34825394

RESUMO

trans-Anethole (anethole) is a phenylpropanoid; with other drugs, it exhibits synergistic activity against several fungi and is expected to be used in new therapies that cause fewer patient side effects. However, the detailed substructure(s) of the molecule responsible for this synergy has not been fully elucidated. We investigated the structure-activity relationships of phenylpropanoids and related derivatives, with particular attention on the methoxy group and the double bond of the propenyl group in anethole, as well as the length of the p-alkyl chain in p-alkylanisoles. Antifungal potency was largely related to p-alkyl chain length and the methoxy group of anethole, but not to the double bond of its propenyl group. Production of reactive oxygen species also played a role in these fungicidal activities. Inhibition of drug efflux was associated with the length of the p-alkyl chain and the double bond of the propenyl group in anethole, but not with the methoxy group. Although a desirable synergy was observed between n-dodecanol and anethole or p-alkylanisoles with a length of C2-C6 in alkyl chains, it cannot be explained away as being solely due to the inhibition of drug efflux. Similar results were obtained when phenylpropanoid derivatives were combined with fluconazole against Candida albicans.


Assuntos
Antifúngicos , Fluconazol , Antifúngicos/farmacologia , Candida albicans , Dodecanol , Farmacorresistência Fúngica , Sinergismo Farmacológico , Fluconazol/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
5.
Transp Res Rec ; 2676(7): 743-762, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38268786

RESUMO

Although it is commonly understood that the average U.S. new vehicle buyer ranks price and safety above environmental attributes, a stated ranking of one shopping criterion above another is not necessarily maintained when consumers make an actual purchase decision. In fact, the distribution of shopping criteria rankings is not well understood, and it is unclear how rankings translate to the attributes of purchased vehicles. This raises several related questions: What is the distribution of shopping criteria rankings across the U.S. and how do they differ among demographic groups and purchasers of different vehicle fuel types or body styles?How do consumers weigh their purchase criteria?How does the environmental impact of a vehicle rank as a purchase criterion for U.S. new vehicle buyers, and its importance differ among gender, age, or income groups?Do purchase criteria differ for consumers who state that they value the environment?Is a consumer's shopping criteria ranking of environmental attributes reflected in the vehicles they consider and ultimately purchase? We explore these issues using data from an extensive survey of new vehicle buyers in 2014, 2015, and 2016 (approximately 250,000 respondents per year). We broadly find the environmental criterion outranked by preference for safety and performance, but different patterns emerge across groups defined by household income, purchased vehicle fuel type, and other measures of respondent attitude toward the environment. Stated preferences for environmental attributes align with higher fuel economy and greater likelihood of electric or hybrid fuel type within considered and purchased vehicles.

6.
Lett Appl Microbiol ; 72(4): 390-398, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33128810

RESUMO

Amphotericin B (AmB), a typical polyene macrolide antifungal agent, is widely used to treat systemic mycoses. In the present study, we show that the fungicidal activity of AmB was enhanced by benzyl isothiocyanate (BITC), a cruciferous plant-derived compound, in the budding yeast, Saccharomyces cerevisiae. In addition to forming a molecular complex with ergosterol present in fungal cell membranes to form K+ -permeable ion channels, AmB has been recognized to mediate vacuolar membrane disruption resulting in lethal effects. BITC showed no effect on AmB-induced plasma membrane permeability; however, it amplified AmB-induced vacuolar membrane disruption in S. cerevisiae. Furthermore, the BITC-enhanced fungicidal effects of AmB significantly decreased cell viability due to the disruption of vacuoles in the pathogenic fungus Candida albicans. The application of the combinatorial antifungal effect of AmB and BITC may aid in dose reduction of AmB in clinical antifungal therapy and consequently decrease side effects in patients. These results also have significant implications for the development of vacuole-targeting chemotherapy against fungal infections.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Isotiocianatos/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Sinergismo Farmacológico , Quimioterapia Combinada , Ergosterol/metabolismo , Humanos , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo
7.
Nano Lett ; 20(11): 8001-8007, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-32985892

RESUMO

The quantum anomalous Hall (QAH) effect appears in ferromagnetic topological insulators (FMTIs) when a Dirac mass gap opens in the spectrum of the topological surface states (SSs). Unaccountably, although the mean mass gap can exceed 28 meV (or ∼320 K), the QAH effect is frequently only detectable at temperatures below 1 K. Using atomic-resolution Landau level spectroscopic imaging, we compare the electronic structure of the archetypal FMTI Cr0.08(Bi0.1Sb0.9)1.92Te3 to that of its nonmagnetic parent (Bi0.1Sb0.9)2Te3, to explore the cause. In (Bi0.1Sb0.9)2Te3, we find spatially random variations of the Dirac energy. Statistically equivalent Dirac energy variations are detected in Cr0.08(Bi0.1Sb0.9)1.92Te3 with concurrent but uncorrelated Dirac mass gap disorder. These two classes of SS electronic disorder conspire to drastically suppress the minimum mass gap to below 100 µeV for nanoscale regions separated by <1 µm. This fundamentally limits the fully quantized anomalous Hall effect in Sb2Te3-based FMTI materials to very low temperatures.

8.
Osteoporos Int ; 30(3): 697, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30806728

RESUMO

The article Lower grip strength and dynamic body balance in women with distal radial fractures, written by. K. Fujita, H. Kaburagi, A. Nimura, T. Miyamoto, Y. Wakabayashi, Y. Seki, H. Aoyama, H. Shimura, R. Kato, A. Okawa was originally published electronically on the publisher's internet portal.

9.
Osteoporos Int ; 30(5): 949-956, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30607458

RESUMO

In this case-control study, we concluded that women with distal radial fractures who were surgically treated showed lower grip strength and dynamic body balancing than those of controls. These results suggest that measurements of grip strength and dynamic body balance may be useful screening tools to assess future fracture risk. INTRODUCTION: Patients with distal radial fractures (DRFs) are at risk of future fragility fractures. However, their physical characteristics and tendencies for falls remain unclear. We aimed to compare the physical characteristics of women with and without distal radial fractures. METHODS: We included 128 women with a DRF as their first fragility fracture (fracture group) who underwent surgical treatment. Concurrently, 128 age- and sex-matched participants without a history of fragility fractures were selected as controls (control group). The participants underwent assessments of grip strength and the body balancing ability test. Measurements were taken twice in the fracture group, at 2 weeks and 6 months postoperatively, and once in the control group. The body balancing ability test included the Functional Reach Test, Timed Up and Go test (TUG), 2-Step test (2ST), and Timed Uni-pedal Stance test. The participants also completed questionnaires about their health. RESULTS: There were no significant differences (p > 0.05) in patient characteristics between the groups. The fracture group showed lower grip strength across all age groups. In the DRF group, prolonged TUG time was observed at 2 weeks postoperatively in all age groups and at 6 months in participants aged 55-74 years; the 2ST score was significantly lower in participants aged between 65 and 74 years. CONCLUSIONS: Women with DRF demonstrated lower grip strength and dynamic body balancing ability. Lower grip strength and dynamic body balancing ability were identified as significant risk factors in women with DRF, suggesting that these may be useful screening tools to assess fracture risk.


Assuntos
Força da Mão/fisiologia , Fraturas por Osteoporose/fisiopatologia , Equilíbrio Postural/fisiologia , Fraturas do Rádio/fisiopatologia , Acidentes por Quedas , Adulto , Idoso , Densidade Óssea/fisiologia , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/etiologia , Período Pós-Operatório , Curva ROC , Fraturas do Rádio/etiologia , Fraturas do Rádio/cirurgia , Medição de Risco/métodos , Fatores de Risco
10.
Lett Appl Microbiol ; 69(6): 403-410, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31596500

RESUMO

Parabens have been widely used as antimicrobial preservatives in cosmetics, pharmaceuticals, foods and beverages. Commonly, methyl-, ethyl-, propyl- and butylparaben are used independently or in combination to maintain the quality of industrial products, and they are considered to have low toxicity. However, recent evidence has suggested that parabens are toxic in mammalian cells, and parabens have been associated with allergic-contact dermatitis, breast cancer and changes in testosterone levels. Sulforaphane, a cruciferous vegetable-derived isothiocyanate, was effective in decreasing the growth inhibitory concentrations of ethyl-, propyl-, butyl- and methylparaben in the yeast Saccharomyces cerevisiae. The sulforaphane-enhanced fungicidal effects of methylparaben were deemed to be caused by drastic cell membrane damage and the leakage of internal substances, such as nucleotides, from S. cerevisiae cells. Moreover sulforaphane markedly decreased the minimum concentration of methyl- and ethylparaben required to inhibit the growth of various microbes, such as the pathogenic yeast that causes severe mycosis, Candida albicans; the filamentous fungi Aspergillus niger; and the Gram-negative bacterium Escherichia coli. Enhanced antimicrobial activity from the beneficial components of edible plants may increase paraben efficacy at low concentrations and minimize preservative-induced side effects in consumers. SIGNIFICANCE AND IMPACT OF THE STUDY: Sulforaphane, a natural and beneficial cruciferous vegetable-derived isothiocyanate, increased the ability of parabens to disrupt fungal cell membranes. Paraben-containing products have been reported to cause allergic contact dermatitis and drug hypersensitivity; therefore, methods to preserve organic products that may reduce the concentrations of parabens are both timely and necessary. In this study, we found that the combined antimicrobial effects of sulforaphane and parabens had the potential to reduce the paraben concentration needed to preserve organic products, thereby indicating that paraben toxicity may be reduced without affecting its activity as a preservative.


Assuntos
Antifúngicos/farmacologia , Isotiocianatos/farmacologia , Parabenos/farmacologia , Conservantes Farmacêuticos/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Alérgenos , Animais , Cosméticos/química , Sinergismo Farmacológico , Feminino , Humanos , Sulfóxidos , Verduras/química
11.
Lett Appl Microbiol ; 68(1): 17-23, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30276838

RESUMO

Drug resistance commonly occurs when treating immunocompromised patients who have fungal infections. Curcumin, is a compound isolated from Curcuma longa, has been reported to inhibit drug efflux in several human cell lines and nonpathogenic budding yeast Saccharomyces cerevisiae cells that overexpresses the ATP-binding cassette (ABC) transporters S. cerevisiae Pdr5p and pathogenic Candida albicans Cdr1p and Cdr2p. The aim of this study was to examine the effects of curcumin on multidrug resistance in a wild-type strain of the budding yeast with an intrinsic expression system of multidrug efflux-related genes. The antifungal activity of dodecanol alone was temporary against S. cerevisiae; however, restoration of cell viability was completely inhibited when the cells were co-treated with dodecanol and curcumin. Furthermore, restriction of rhodamine 6G (R6G) efflux from the cells and intracellular accumulation of R6G were observed with curcumin treatment. Reverse transcription-polymerase chain reaction analysis revealed that curcumin reduced the dodecanol-induced overexpression of the ABC transporter-related genes PDR1, PDR3 and PDR5 to their control levels in untreated cells. Curcumin can directly restrict the glucose-induced drug efflux and inhibits the expression of the ABC transporter gene PDR5, and can thereby inhibit the efflux of dodecanol from S. cerevisiae cells. Curcumin is effective in potentiating the efficacy of antifungal drugs via its effects on ABC transporters. SIGNIFICANCE AND IMPACT OF THE STUDY: Drug resistance is common in immunocompromised patients with fungal infections. Curcumin, isolated from Curcuma longa, inhibits drug efflux in nonpathogenic budding yeast Saccharomyces cerevisiae cells overexpressing ABC transporters S. cerevisiae Pdr5p and pathogenic Candida albicans Cdr1p and Cdr2p. We examined the effects of curcumin on multidrug resistance in a wild-type strain of the budding yeast with an intrinsic expression system of multidrug efflux-related genes. Curcumin directly inhibited drug efflux and also suppressed the PDR5 expression, thereby enhancing the antifungal effects. Thus, curcumin potentially promotes the efficacy of antifungals via its effects on ABC transporters in wild-type fungal strains.


Assuntos
Antifúngicos/farmacologia , Transporte Biológico/efeitos dos fármacos , Curcumina/farmacologia , Dodecanol/farmacologia , Farmacorresistência Fúngica Múltipla/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Transportadores de Cassetes de Ligação de ATP/biossíntese , Candida albicans/efeitos dos fármacos , Proteínas de Ligação a DNA/biossíntese , Sinergismo Farmacológico , Quimioterapia Combinada , Proteínas Fúngicas/biossíntese , Humanos , Proteínas de Membrana Transportadoras/biossíntese , Rodaminas/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/biossíntese , Saccharomycetales/metabolismo , Fatores de Transcrição/biossíntese
12.
Osteoarthritis Cartilage ; 26(11): 1551-1561, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30086379

RESUMO

OBJECTIVE: FGFR3 chondrodysplasia is caused by a gain-of-function mutation of the FGFR3 gene. The disease causes abnormal growth plate cartilage and lacks effective drug treatment. We sought to establish an in vivo model for the study of FGFR3 chondrodysplasia pathology and drug testing. DESIGN: We created cartilage from human induced pluripotent stem cells (hiPSCs) and transplanted the cartilage into the subcutaneous spaces of immunodeficient mice. We then created cartilage from the hiPSCs of patients with FGFR3 chondrodysplasia and transplanted them into immunodeficient mice. We treated some mice with a FGFR inhibitor after the transplantation. RESULTS: Xenografting the hiPSC-derived cartilage reproduced human growth plate cartilage consisting of zones of resting, proliferating, prehypertrophic and hypertrophic chondrocytes and bone in immunodeficient mice. Immunohistochemistry of xenografts using anti-human nuclear antigen antibody indicated that all chondrocytes in growth plate cartilage were human, whereas bone was composed of human and mouse cells. The pathology of small hypertrophic chondrocytes due to up-regulated FGFR3 signaling in FGFR3 skeletal dysplasia was recapitulated in growth plate cartilage formed in the xenografts of patient-specific hiPSC-derived cartilage. The mean diameters of hypertrophic chondrocytes between wild type and thanatophoric dysplasia were significantly different (95% CI: 13.2-26.9; n = 4 mice, one-way analysis of variance (ANOVA)). The pathology was corrected by systemic administration of a FGFR inhibitor to the mice. CONCLUSION: The patient-specific growth plate cartilage xenograft model for FGFR3 skeletal dysplasia indicated recapitulation of pathology and effectiveness of a FGFR inhibitor for treatment and warrants more study for its usefulness to study disease pathology and drug testing.


Assuntos
Cartilagem/patologia , Lâmina de Crescimento/patologia , Mutação , Osteocondrodisplasias/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Animais , Cartilagem/metabolismo , Ciclo Celular , Diferenciação Celular , Proliferação de Células , Modelos Animais de Doenças , Lâmina de Crescimento/metabolismo , Xenoenxertos , Camundongos , Osteocondrodisplasias/metabolismo , Osteocondrodisplasias/patologia , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais
13.
Scand J Med Sci Sports ; 28(1): 246-251, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28207961

RESUMO

Previous history of medial tibial stress syndrome (MTSS) is a risk factor for MTSS relapse, which suggests that there might be some physical factors that are related to MTSS development in runners with a history of MTSS. The relationship between MTSS and muscle stiffness can be assessed in a cross-sectional study that measures muscle stiffness in subjects with a history of MTSS, who do not have pain at the time of measurement, and in those without a history of MTSS. The purpose of this study was to compare the shear elastic modulus, which is an index of muscle stiffness, of all posterior lower leg muscles of subjects with a history of MTSS and those with no history and investigate which muscles could be related to MTSS. Twenty-four male collegiate runners (age, 20.0±1.7 years; height, 172.7±4.8 cm; weight, 57.3±3.7 kg) participated in this study; 14 had a history of MTSS, and 10 did not. The shear elastic moduli of the lateral gastrocnemius, medial gastrocnemius, soleus, peroneus longus, peroneus brevis, flexor hallucis longus, flexor digitorum longus, and tibialis posterior were measured using shear wave elastography. The shear elastic moduli of the flexor digitorum longus and tibialis posterior were significantly higher in subjects with a history of MTSS than in those with no history. However, there was no significant difference in the shear elastic moduli of other muscles. The results of this study suggest that flexor digitorum longus and tibialis posterior stiffness could be related to MTSS.


Assuntos
Módulo de Elasticidade , Síndrome do Estresse Tibial Medial/fisiopatologia , Músculo Esquelético/fisiopatologia , Corrida , Estudos Transversais , Humanos , Masculino , Adulto Jovem
14.
Hum Reprod ; 32(3): 514-522, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28104696

RESUMO

STUDY QUESTION: Is actin capping protein (CP) ß3 involved in human spermatogenesis and male infertility? SUMMARY ANSWER: Human CPß3 (hCPß3) is expressed in testis, changes its localization dynamically during spermatogenesis, and has some association with male infertility. WHAT IS KNOWN ALREADY: The testis-specific α subunit of CP (CPα3) was previously identified in human, and mutations in the cpα3 gene in mouse were shown to induce malformation of the sperm head and male infertility. However, CPß3, which is considered to be a heterodimeric counterpart of CPα3, has been neither characterized in human nor reported in association with male infertility. STUDY DESIGN, SIZE, DURATION: To confirm the existence of CPß3 in human testis, fresh semen samples from proven fertile men were analyzed. To investigate protein expression during spermatogenesis, cryopreserved testis obtained from men with obstructive azoospermia were examined by immunofluorescent analysis. To assess the association of CP with male infertility, we compared protein expression of human CPα3 (hCPα3) and hCPß3 using immunofluorescent analysis of cryopreserved sperm between men with normozoospermia (volunteers: Normo group, n = 20) and infertile men with oligozoospermia and/or asthenozoospermia (O + A group, n = 21). PARTICIPANTS/MATERIALS, SETTING, METHODS: The tissue-specific expression of hCPß3 was investigated by RT-PCR and Western blot analysis. To investigate whether hCPα3 and hCPß3 form a heterodimer, a tandem expression vector containing hcpα3 tagged with monomeric red fluorescent protein 1 and hcpß3 tagged with enhanced green fluorescent protein in a single plasmid was constructed and analyzed by co-immunoprecipitation (Co-IP) assay. The protein expression profiles of hCPα3 and hCPß3 during spermatogenesis were examined by immunohistochemical analysis using human spermatogenic cells. The protein expressions of hCPα3 and hCPß3 in sperm were compared between the Normo and O + A groups by immunohistochemical analysis. MAIN RESULTS AND THE ROLE OF CHANCE: RT-PCR showed that mRNA of hcpß3 was expressed exclusively in testis. Western blot analysis detected hCPß3 with anti-bovine CPß3 antibody. Co-IP assay with recombinant protein showed that hCPα3 and hCPß3 form a protein complex. At each step during spermatogenesis, the cellular localization of hCPß3 changed dynamically. In spermatogonia, hCPß3 showed a slight signal in cytoplasm. hCPß3 expression was conspicuous mainly from spermatocytes, and hCPß3 localization dynamically migrated from cytoplasm to the acrosomal cap and acrosome. In mature spermatozoa, hCPß3 accumulated in the postacrosomal region and less so at the midpiece of the tail. Double-staining analysis revealed that hCPα3 localization was identical to hCPß3 at every step in the spermatogenic cells. Most spermatozoa from the Normo group were stained homogenously by both hCPα3 and hCPß3. In contrast, significantly more spermatozoa in the O + A versus Normo group showed heterogeneous or lack of staining for either hCPα3 or hCPß3 (abnormal staining) (P < 0.001). The percentage of abnormal staining was higher in the O + A group (52.4 ± 3.0%) than in the Normo group (31.2 ± 2.5%). Even by confining the observations to morphologically normal spermatozoa selected in accordance with David's criteria, the percentage of abnormal staining was still higher in the O + A group (39.9 ± 2.9%) versus the Normo group (22.5 ± 2.1%) (P < 0.001). hCPß3 in conjunction with hCPα3 seemed to play an important role in spermatogenesis and may be associated with male infertility. LARGE SCALE DATA: Not applicable. LIMITATIONS REASONS FOR CAUTION: Owing to the difficulty of collecting fresh samples of human testis, we used cryopreserved samples from testicular sperm extraction. To examine the interaction of spermatogenic cells or localization in seminiferous tubules, fresh testis sample of healthy males are ideal. WIDER IMPLICATIONS OF THE FINDINGS: The altered expression of hCPα3 and hCPß3 may not only be a cause of male infertility but also a prognostic factor for the results of ART. They may be useful biomarkers to determine the fertilization ability of human sperm in ART. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by a Grant-in-Aid for Young Scientists (B) from the Japan Society for the Promotion of Science (JP16K20133). The authors declare no competing interests.


Assuntos
Proteínas de Capeamento de Actina/metabolismo , Infertilidade Masculina/diagnóstico , Espermatogênese/fisiologia , Espermatozoides/metabolismo , Testículo/metabolismo , Adulto , Astenozoospermia/metabolismo , Azoospermia/metabolismo , Biomarcadores/metabolismo , Humanos , Infertilidade Masculina/metabolismo , Masculino
15.
Mol Psychiatry ; 20(4): 459-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25070536

RESUMO

Human mutations in PQBP1, a molecule involved in transcription and splicing, result in a reduced but architecturally normal brain. Examination of a conditional Pqbp1-knockout (cKO) mouse with microcephaly failed to reveal either abnormal centrosomes or mitotic spindles, increased neurogenesis from the neural stem progenitor cell (NSPC) pool or increased cell death in vivo. Instead, we observed an increase in the length of the cell cycle, particularly for the M phase in NSPCs. Corresponding to the developmental expression of Pqbp1, the stem cell pool in vivo was decreased at E10 and remained at a low level during neurogenesis (E15) in Pqbp1-cKO mice. The expression profiles of NSPCs derived from the cKO mouse revealed significant changes in gene groups that control the M phase, including anaphase-promoting complex genes, via aberrant transcription and RNA splicing. Exogenous Apc4, a hub protein in the network of affected genes, recovered the cell cycle, proliferation, and cell phenotypes of NSPCs caused by Pqbp1-cKO. These data reveal a mechanism of brain size control based on the simple reduction of the NSPC pool by cell cycle time elongation. Finally, we demonstrated that in utero gene therapy for Pqbp1-cKO mice by intraperitoneal injection of the PQBP1-AAV vector at E10 successfully rescued microcephaly with preserved cortical structures and improved behavioral abnormalities in Pqbp1-cKO mice, opening a new strategy for treating this intractable developmental disorder.


Assuntos
Terapia Genética , Microcefalia/genética , Microcefalia/terapia , Células-Tronco Neurais/fisiologia , Proteínas Nucleares/deficiência , Adenoviridae/genética , Animais , Subunidade Apc4 do Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Apoptose/genética , Encéfalo/patologia , Proteínas de Transporte/genética , Moléculas de Adesão Celular/metabolismo , Ciclo Celular , Proliferação de Células , Proteínas de Ligação a DNA , Modelos Animais de Doenças , Embrião de Mamíferos , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Microcefalia/patologia , Nestina/genética , Nestina/metabolismo , Neurogênese , Proteínas Nucleares/genética , Sinapsinas/genética , Sinapsinas/metabolismo
16.
Nature ; 466(7304): 347-51, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20631795

RESUMO

In the high-transition-temperature (high-T(c)) superconductors the pseudogap phase becomes predominant when the density of doped holes is reduced. Within this phase it has been unclear which electronic symmetries (if any) are broken, what the identity of any associated order parameter might be, and which microscopic electronic degrees of freedom are active. Here we report the determination of a quantitative order parameter representing intra-unit-cell nematicity: the breaking of rotational symmetry by the electronic structure within each CuO(2) unit cell. We analyse spectroscopic-imaging scanning tunnelling microscope images of the intra-unit-cell states in underdoped Bi(2)Sr(2)CaCu(2)O(8 +) (delta) and, using two independent evaluation techniques, find evidence for electronic nematicity of the states close to the pseudogap energy. Moreover, we demonstrate directly that these phenomena arise from electronic differences at the two oxygen sites within each unit cell. If the characteristics of the pseudogap seen here and by other techniques all have the same microscopic origin, this phase involves weak magnetic states at the O sites that break 90 degrees -rotational symmetry within every CuO(2) unit cell.

17.
Anim Genet ; 47(1): 62-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26763159

RESUMO

Tractability, or how easily animals can be trained and controlled, is an important behavioural trait for the management and training of domestic animals, but its genetic basis remains unclear. Polymorphisms in the serotonin receptor 1A gene (HTR1A) have been associated with individual variability in anxiety-related traits in several species. In this study, we examined the association between HTR1A polymorphisms and tractability in Thoroughbred horses. We assessed the tractability of 167 one-year-old horses reared at a training centre for racehorses using a questionnaire consisting of 17 items. A principal components analysis of answers contracted the data to five principal component (PC) scores. We genotyped two non-synonymous single nucleotide polymorphisms (SNPs) in the horse HTR1A coding region. We found that one of the two SNPs, c.709G>A, which causes an amino acid change at the intracellular region of the receptor, was significantly associated with scores of four of five PCs in fillies (all Ps < 0.05) and one PC in colts (P < 0.01). Horses carrying an A allele at c.709G>A showed lower tractability. This result provides the first evidence that a polymorphism in a serotonin-related gene may affect tractability in horses with the effect partially different depending on sex.


Assuntos
Comportamento Animal , Cavalos/genética , Personalidade/genética , Polimorfismo de Nucleotídeo Único , Receptor 5-HT1A de Serotonina/genética , Alelos , Animais , Feminino , Genótipo , Masculino
18.
Br J Cancer ; 112(10): 1709-16, 2015 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-25880011

RESUMO

BACKGROUND: In Asians, the risk of irinotecan-induced severe toxicities is related in part to UGT1A1*6 (UGT, UDP glucuronosyltransferase) and UGT1A1*28, variant alleles that reduce the elimination of SN-38, the active metabolite of irinotecan. We prospectively studied the relation between the UGT1A1 genotype and the safety of irinotecan-based regimens in Japanese patients with advanced colorectal cancer, and then constructed a nomogram for predicting the risk of severe neutropenia in the first treatment cycle. METHODS: Safety data were obtained from 1312 patients monitored during the first 3 cycles of irinotecan-based regimen in a prospective observational study. In development of the nomogram, multivariable logistic regression analysis was used to test the associations of candidate factors to severe neutropenia in the first cycle. The final nomogram based on the results of multivariable analysis was constructed and validated internally using a bootstrapping technique and externally in an independent data set (n=350). RESULTS: The UGT1A1 genotype was confirmed to be associated with increased risks of irinotecan-induced grade 3 or 4 neutropenia and diarrhoea. The final nomogram included type of regimen, administered dose of irinotecan, gender, age, UGT1A1 genotype, Eastern Cooperative Oncology Group performance status, pre-treatment absolute neutrophil count, and total bilirubin level. The model was validated both internally (bootstrap-adjusted concordance index, 0.69) and externally (concordance index, 0.70). CONCLUSIONS: Our nomogram can be used before treatment to accurately predict the probability of irinotecan-induced severe neutropenia in the first cycle of therapy. Additional studies should evaluate the effect of nomogram-guided dosing on efficacy in patients receiving irinotecan.


Assuntos
Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neutropenia/induzido quimicamente , Neutropenia/genética , Nomogramas , Idoso , Alelos , Povo Asiático/genética , Bilirrubina/metabolismo , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Predisposição Genética para Doença , Genótipo , Glucuronosiltransferase/genética , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Neutropenia/metabolismo , Neutropenia/patologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Estudos Prospectivos
19.
Phys Rev Lett ; 114(19): 195002, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26024175

RESUMO

A novel direct core heating fusion process is introduced, in which a preimploded core is predominantly heated by energetic ions driven by LFEX, an extremely energetic ultrashort pulse laser. Consequently, we have observed the D(d,n)^{3}He-reacted neutrons (DD beam-fusion neutrons) with the yield of 5×10^{8} n/4π sr. Examination of the beam-fusion neutrons verified that the ions directly collide with the core plasma. While the hot electrons heat the whole core volume, the energetic ions deposit their energies locally in the core, forming hot spots for fuel ignition. As evidenced in the spectrum, the process simultaneously excited thermal neutrons with the yield of 6×10^{7} n/4π sr, raising the local core temperature from 0.8 to 1.8 keV. A one-dimensional hydrocode STAR 1D explains the shell implosion dynamics including the beam fusion and thermal fusion initiated by fast deuterons and carbon ions. A two-dimensional collisional particle-in-cell code predicts the core heating due to resistive processes driven by hot electrons, and also the generation of fast ions, which could be an additional heating source when they reach the core. Since the core density is limited to 2 g/cm^{3} in the current experiment, neither hot electrons nor fast ions can efficiently deposit their energy and the neutron yield remains low. In future work, we will achieve the higher core density (>10 g/cm^{3}); then hot electrons could contribute more to the core heating via drag heating. Together with hot electrons, the ion contribution to fast ignition is indispensable for realizing high-gain fusion. By virtue of its core heating and ignition, the proposed scheme can potentially achieve high gain fusion.

20.
Phys Rev Lett ; 115(10): 102501, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26382672

RESUMO

Differential cross sections of isoscalar and isovector spin-M1 (0(+)→1(+)) transitions are measured using high-energy-resolution proton inelastic scattering at E(p)=295 MeV on (24)Mg, (28)Si, (32)S, and (36)Ar at 0°-14°. The squared spin-M1 nuclear transition matrix elements are deduced from the measured differential cross sections by applying empirically determined unit cross sections based on the assumption of isospin symmetry. The ratios of the squared nuclear matrix elements accumulated up to E(x)=16 MeV compared to a shell-model prediction are 1.01(9) for isoscalar and 0.61(6) for isovector spin-M1 transitions, respectively. Thus, no quenching is observed for isoscalar spin-M1 transitions, while the matrix elements for isovector spin-M1 transitions are quenched by an amount comparable with the analogous Gamow-Teller transitions on those target nuclei.

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