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1.
Nat Commun ; 14(1): 8258, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38086872

RESUMO

Ultrafast laser excitation provides a means to transiently realize long-range ordered electronic states of matter that are hidden in thermal equilibrium. Recently, this approach has unveiled a variety of thermally inaccessible ordered states in strongly correlated materials, including charge density wave, ferroelectric, magnetic, and intertwined charge-orbital ordered states. However, more exotic hidden states exhibiting higher multipolar ordering remain elusive owing to the challenge of directly manipulating and detecting them with light. Here we demonstrate a method to induce a dynamical transition from a thermally allowed to a thermally forbidden spin-orbit entangled quadrupolar ordered state in Ca2RuO4 by coherently exciting a phonon that is strongly coupled to the order parameter. Combining probe photon energy-resolved coherent phonon spectroscopy measurements with model Hamiltonian calculations, we show that the dynamical transition is manifested through anomalies in the temperature, pump excitation fluence, and probe photon energy dependence of the strongly coupled phonon. With this procedure, we introduce a general pathway to uncover hidden multipolar ordered states and to control their re-orientation on ultrashort timescales.

2.
Phys Rev Lett ; 128(18): 187402, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35594087

RESUMO

The fate of a Mott insulator under strong low frequency optical driving conditions is a fundamental problem in quantum many-body dynamics. Using ultrafast broadband optical spectroscopy, we measured the transient electronic structure and charge dynamics of an off-resonantly pumped Mott insulator Ca_{2}RuO_{4}. We observe coherent bandwidth renormalization and nonlinear doublon-holon pair production occurring in rapid succession within a sub-100-fs pump pulse duration. By sweeping the electric field amplitude, we demonstrate continuous bandwidth tuning and a Keldysh crossover from a multiphoton absorption to quantum tunneling dominated pair production regime. Our results provide a procedure to control coherent and nonlinear heating processes in Mott insulators, facilitating the discovery of novel out-of-equilibrium phenomena in strongly correlated systems.

3.
Plants (Basel) ; 11(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35161261

RESUMO

The recovery of physiologically bioactive ingredients from agricultural wastes as an abundant and low-cost source for the production of high value-added mutraceuticlas has been recognized and supported for the commercial interests and sustainable managements. In the extraction of geniposide for the development of natural food colorants from the dried fruits of Gardenia jasminoides Rubiaceae, the gardenia fruit waste (GFW) still remaining 0.86% (w/w) of crocins has always been discarded without any further treatments Until now, there was no simple and effective protocol for high-purity trans-crocein (TC) preparation without the coexistence of non-biologically active cis-crocein from GFW. We proposed an effective process to obtain the compound as follows. Crocins were extracted firstly by 50% of ethanol in the highest yield of 8.61 mg/g (w/w) from GFW. After the HPD-100 column fractionation in the collecting of crocins, the conversion ratio of 75% of crocins to crocetins can be obtained from the commercial available enzyme- Celluclast® 1.5 L. The crocins hydrolyzed products, were then separated through the HPD-100 resin adsorption and finally purified with the centrifugal partition chromatography (CPC) in single-step to obtain TC in a purity of 96.76 ± 0.17%. Conclusively, the effective enzyme transformation and purification co-operated with CPC technologies on crocins resulted in a high purity product of TC may be highly application in the commercial production.

4.
J Virol Methods ; 292: 114117, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33657432

RESUMO

Hepatitis B virus (HBV) capsids are assembled from HBV core protein and assembly is a critical step in the propagation of the virus. Due to its multiple functions in the viral life cycle, core is an attractive target for new antiviral therapies. For HBV capsid assembly modulators (CAMs), several resistance mutants have been identified, both from the clinic and in vitro. However, currently there is no convenient in vitro assay to monitor resistance to CAMs in the clinic. Here, we developed a facile, cassette-based phenotyping assay to assess the antiviral activity of CAMs on a panel of clinical isolates. Using this system, the core genes from 13 patients infected with HBV genotypes A-H were expressed as chimeric virus and tested for sensitivity to CAMs. No substantial differences in antiviral activity were observed across genotypes due to the conservation of the drug binding pocket. In addition, we tested a panel of constructs encoding 13 single amino acid polymorphs in the CAM binding site, including some polymorphs with previously-described resistance to CAMs. Overall, 11 of 13 constructs replicated in vitro, 6 constructs showed reduced susceptibility to CAMs. The 11 polymorphs which could replicate in vitro remained sensitive to the nucleotide analog tenofovir alafenamide (TAF), indicating that there is no cross-resistance.


Assuntos
Capsídeo , Vírus da Hepatite B , Antivirais/farmacologia , Proteínas do Capsídeo/genética , Vírus da Hepatite B/genética , Humanos , Montagem de Vírus , Replicação Viral
5.
Clin Case Rep ; 8(10): 1867-1871, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33088508

RESUMO

Legius syndrome is characterized by numerous café-au-lait macules and intertriginous freckling, but typically lacks the distinctive tumor manifestations of neurofibromatosis type 1. We report two siblings with Legius syndrome and Lisch nodules illustrating the importance of eye surveillance in these patients.

7.
Phys Rev Lett ; 124(2): 027601, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-32004043

RESUMO

The transition metal thiophosphates MPS_{3} (M=Mn, Fe, Ni) are a class of van der Waals stacked insulating antiferromagnets that can be exfoliated down to the ultrathin limit. MnPS_{3} is particularly interesting because its Néel ordered state breaks both spatial-inversion and time-reversal symmetries, allowing for a linear magnetoelectric phase that is rare among van der Waals materials. However, it is unknown whether this unique magnetic structure of bulk MnPS_{3} remains stable in the ultrathin limit. Using optical second harmonic generation rotational anisotropy, we show that long-range linear magnetoelectric type Néel order in MnPS_{3} persists down to at least 5.3 nm thickness. However an unusual mirror symmetry breaking develops in ultrathin samples on SiO_{2} substrates that is absent in bulk materials, which is likely related to substrate induced strain.

8.
Mil Med ; 185(7-8): e1322-e1325, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31825081

RESUMO

The spectrum of the neurological effects of high-altitude exposure can range from high-altitude headache and acute mountain sickness, to the more severe end of the spectrum with high-altitude cerebral edema. In general, patients with known unstable preexisting neurological conditions and those patients with residual neurological deficits from a preexisting neurological condition are discouraged from climbing to high altitudes because of the risk of exacerbation or worsening of symptoms. Although multiple sclerosis exacerbations can be triggered by environmental factors, high-altitude exposure has not been reported as a potential trigger. We are reporting the case of a multiple sclerosis exacerbation presenting in an active duty U.S. Air Force serviceman upon ascending and descending Mt. Fuji within the same day.


Assuntos
Doença da Altitude , Esclerose Múltipla , Doença Aguda , Altitude , Doença da Altitude/complicações , Cefaleia , Humanos , Esclerose Múltipla/complicações , Doenças do Sistema Nervoso
10.
Aust N Z J Obstet Gynaecol ; 59(5): 677-683, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30734276

RESUMO

BACKGROUND: Vaginal instrumental delivery is a common obstetrical intervention, but its effect on children's later development is not well known. AIMS: To determine if vaginal instrumental delivery is associated with adverse neurodevelopment as measured by school achievement. MATERIAL AND METHODS: We performed a whole-of-population study involving linkage of routinely collected perinatal data with school assessments among children born in South Australia from 1999 to 2008. Participants were singleton children born by forceps (n = 5494), ventouse (n = 6988), or normal delivery (n = 80 803). School achievement was measured through performance on the National Assessment Program in Literacy and Numeracy (NAPLAN), at around eight years of age. This assessment involved five domains and scores were categorised according to performing at or above National Minimum Standards (NMS). Effects of instrumental versus normal vaginal delivery were analysed via augmented inverse probability weighting (AIPW), taking into account a variety of maternal, perinatal and sociodemographic characteristics. RESULTS: In unadjusted analyses, instrumental delivery was not associated with poor NAPLAN scores. AIPW analyses also suggested that instrumental delivery had minimal adverse effect on NAPLAN scores, with the largest difference being lower spelling scores among forceps-delivered children (-0.022 (95% CI -0.0053-0.009)) compared with spontaneous vaginal births. The findings were consistent among exploratory subgroup analyses involving births in the absence of prolonged labour, with APGAR ≥ 9, and among normotensive and non-diabetic mothers. CONCLUSION: In singleton children born at term, instrumental delivery does not have an adverse effect on neurodevelopment as measured by NAPLAN performance at age eight.


Assuntos
Traumatismos do Nascimento/epidemiologia , Parto Obstétrico/efeitos adversos , Adulto , Traumatismos do Nascimento/etiologia , Criança , Desenvolvimento Infantil , Bases de Dados Factuais , Demografia , Escolaridade , Extração Obstétrica/efeitos adversos , Feminino , Humanos , Recém-Nascido , Gravidez , Fatores Socioeconômicos , Austrália do Sul/epidemiologia
11.
J Clin Microbiol ; 57(4)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30728196

RESUMO

Voxilaprevir is a direct-acting antiviral agent (DAA) that targets the NS3/4A protease of hepatitis C virus (HCV). High sequence diversity of HCV and inadequate drug exposure during unsuccessful treatment may lead to the accumulation of variants with reduced susceptibility to DAAs, including NS3/4A protease inhibitors such as voxilaprevir. The voxilaprevir susceptibility of clinical and laboratory strains of HCV was assessed. The NS3 protease regions of viruses belonging to 6 genotypes and 29 subtypes from 345 DAA-naive or -experienced (including protease inhibitor) patients and 344 genotype 1 to 6 replicons bearing engineered NS3 resistance-associated substitutions (RASs) were tested in transient-transfection assays. The median voxilaprevir 50% effective concentration against NS3 from protease inhibitor-naive patient samples ranged from 0.38 nM for genotype 1 to 5.8 nM for genotype 3. Voxilaprevir susceptibilities of HCV replicons with NS3 RASs were dependent on subtype background and the type and number of substitutions introduced. The majority of RASs known to confer resistance to other protease inhibitors had little to no impact on voxilaprevir susceptibility, except A156L, T, or V in genotype 1 to 4 which conferred >100-fold reductions but exhibited low replication capacity in most genotypes. These data support the use of voxilaprevir in combination with other DAAs in DAA-naive and DAA-experienced patients infected with any subtype of HCV.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Compostos Macrocíclicos/farmacologia , Inibidores de Proteases/farmacologia , Sulfonamidas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Substituição de Aminoácidos , Ácidos Aminoisobutíricos , Ciclopropanos , Farmacorresistência Viral/genética , Genótipo , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Lactamas Macrocíclicas , Leucina/análogos & derivados , Prolina/análogos & derivados , Quinoxalinas
12.
J Cell Biochem ; 120(1): 533-543, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30191601

RESUMO

Glioblastoma (GBM) is the most common malignant brain tumor and is associated with a poor prognosis, with most patients living less than a year after diagnosis. Given that GBM nearly always recurs after conventional treatments, there is an urgent need to identify novel molecular targets. Hairless (HR) is a nuclear factor enriched in the skin and has been previously implicated in hair cycling. HR is also highly expressed in the brain, but its significance is unknown. We found that human hairless gene (HR) expression is significantly decreased in all GBM subtypes compared with normal brain tissue and is predictive of prognosis, which suggests that loss of HR expression can contribute to GBM pathogenesis. HR was recently discovered to bind to and regulate p53 responsive elements, and thus we hypothesized that HR may have a tumor suppressive function in GBM by modulating p53 target gene expression. We found that HR indeed regulates p53 target genes, including those implicated in cell cycle progression and apoptosis in the GBM-derived U87 cell line, and restoring HR expression triggered G2/M arrest and apoptosis. An analysis of sequenced genomes from patients with GBM revealed 10 HR somatic mutations in patients with glioma, two of which are located in the histone demethylase domain of HR. These two mutations, P996S and K1004N, were reconstructed and found to have impaired p53 transactivating properties. Collectively, the results of our study suggest that HR has tumor suppressive functions in GBM, which may be clinically relevant and a potential avenue for therapeutic intervention.


Assuntos
Neoplasias Encefálicas/genética , Glioblastoma/genética , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/genética , Apoptose/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Histona Desmetilases/genética , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/genética , Mutação , Prognóstico , Domínios Proteicos/genética , Transfecção , Sequenciamento Completo do Genoma
13.
Nat Commun ; 9(1): 1829, 2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29739939

RESUMO

Methylammonium lead iodide perovskite (MAPbI3) exhibits long charge carrier lifetimes that are linked to its high efficiency in solar cells. Yet, the mechanisms governing these unusual carrier dynamics are not completely understood. A leading hypothesis-disproved in this work-is that a large, static bulk Rashba effect slows down carrier recombination. Here, using second harmonic generation rotational anisotropy measurements on MAPbI3 crystals, we demonstrate that the bulk structure of tetragonal MAPbI3 is centrosymmetric with I4/mcm space group. Our calculations show that a significant Rashba splitting in the bandstructure requires a non-centrosymmetric lead iodide framework, and that incorrect structural relaxations are responsible for the previously predicted large Rashba effect. The small Rashba splitting allows us to compute effective masses in excellent agreement with experiment. Our findings rule out the presence of a large static Rashba effect in bulk MAPbI3, and our measurements find no evidence of dynamic Rashba effects.

14.
J Cell Biochem ; 119(1): 69-80, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28543886

RESUMO

The mammalian hairless protein (HR) is a 130 kDa nuclear transcription factor that is essential for proper skin and hair follicle function. Previous studies have focused on the role of HR in skin maintenance and hair cycling. However, the hairless gene (HR) is also expressed in brain and other tissues, where its role remains poorly understood. HR has been reported to contain functional domains that potentially serve in DNA binding, histone demethylation, nuclear translocation and protein-protein interactions. Indeed, HR has been shown to interact with and repress the action of the nuclear receptors for vitamin D and thyroid hormone as well as RAR-related orphan receptor alpha, possibly via recruitment of histone deacetylases. HR may also have important functions in non-skin tissues given that nearly 200 HR mutations have been identified in patients with various cancers, including prostate, breast, lung, melanoma, uterine, and glioma. This suggests that HR and/or mutants thereof have relevance to the growth and survival of cancer cells. For example, the reported intrinsic histone H3K9 demethylase activity of HR may activate dormant genes to contribute to carcinogenesis. Alternatively, the demonstrated ability of HR to interact with p53 and/or the p53 DNA response element to influence p53-regulated pathways may explain, at least in part, why many cancers express mutated HR proteins. In this review, we summarize the current knowledge of HR bioactions, how HR mutations may be contributing to alopecia as well as to cancer, and, finally, outline future directions in the study of this largely enigmatic nuclear protein. J. Cell. Biochem. 119: 69-80, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
Neoplasias/genética , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Alopecia/genética , Neoplasias Encefálicas/genética , Proteínas Correpressoras/metabolismo , Regulação da Expressão Gênica , Doenças do Cabelo/genética , Folículo Piloso/anormalidades , Humanos , Dermatopatias Vesiculobolhosas/genética , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
15.
Am J Med Genet A ; 173(6): 1625-1630, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28462982

RESUMO

Early infantile epileptic encephalopathy-9 (EIEE9) linked to mutations of the PCDH19 gene on the X chromosome was once thought to only affect females. Clinical features of the mutation include early onset of variable types and frequency of recurrent cluster of seizures, mild to profound intellectual disability, autistic traits, psychiatric features, and behavioral disturbances. PCDH19 pathogenic variants usually occur via an unusual X-linked pattern where heterozygous females are affected, but hemizygous males are asymptomatic. Somatic mosaic males for PCDH19 mutations are affected with EIEE9; since this discovery, four somatic mosaic males have been reported. We report the fifth confirmed male with somatic mosaicism of a novel pathogenic variant c.2147+2 T>C located in the splice site of Intron 1 of the PCDH19 gene, which continues to support that cellular interference is responsible for the pathogenic mechanism. The importance of our report is to provide significant knowledge about this rare cause of epilepsy in males, guide subsequent functional studies on males portraying an EIEE9 phenotype that have been potentially misdiagnosed, targeted therapeutic approaches, and further elucidation of this complex and interesting genetic disorder.


Assuntos
Caderinas/genética , Deficiência Intelectual/genética , Mosaicismo , Espasmos Infantis/genética , Genes Ligados ao Cromossomo X , Humanos , Deficiência Intelectual/fisiopatologia , Masculino , Mutação , Fenótipo , Protocaderinas , Sítios de Splice de RNA/genética , Espasmos Infantis/fisiopatologia
16.
J Cell Biochem ; 118(2): 341-350, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27355563

RESUMO

The mammalian hairless (Hr) protein plays critical roles in skin and brain tissues, but how it interacts with DNA and partner protein is only now being defined. Our initial tests of four consensus response elements, revealed that rat Hr can specifically bind to a consensus p53 response element (p53RE), 5'-AGACATGCCTAGACATGCCT-3', but not to response elements for NF-κB, TCF4 or Sp1. We then employed ChIP assays which verified that human HR binds to a p53RE of the GADD45A gene in both HEK293 (embryonic kidney) and U87 (glioblastoma) cells. Further, HR was shown to interact directly with the p53 protein in a co-immunoprecipitation assay. Cotransfections with p53RE reporter gene constructs revealed that rat Hr can boost p53-mediated transactivation of a reporter gene linked to the GADD45A p53RE, but blunts p53-mediated transactivation when the reporter gene is linked to a p21 promoter fragment containing a p53RE, with implications for the regulation of these two cell cycle control genes. Finally, our investigations of HR phosphorylation revealed that rat Hr is a substrate for PKC, but not PKA, and that human HR is phosphorylated in intact U87 cells at Ser-416, located in a highly conserved region which partially fulfills the criteria of a PKC site. We propose that mammalian Hr is a phosphoprotein which can exert cross-talk with the p53 pathway with important implications for the regulation of cell proliferation and differentiation in tissues such as skin and brain where Hr is highly expressed. J. Cell. Biochem. 118: 341-350, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Encéfalo/metabolismo , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Células HEK293 , Humanos , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Especificidade de Órgãos , Fosfoproteínas/genética , Fosforilação/genética , Elementos de Resposta , Pele/metabolismo , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética
17.
Case Rep Neurol ; 8(1): 66-71, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27194986

RESUMO

Gorham-Stout disease (GSD), also known as vanishing bone disease, is a rare disorder, which most commonly presents in children and young adults and is characterized by an excessive proliferation of lymphangiomatous tissue within the bones. This lymphangiomatous proliferation often affects the cranium and, due to the proximate location to the dura surrounding cerebrospinal fluid (CSF) spaces, can result in CSF leaks manifesting as intracranial hypotension with clinical symptoms to include orthostatic headache, nausea, and vertigo. We present the case of a boy with GSD and a known history of migraine headaches who presented with persistent headaches due to increased intracranial pressure. Although migraine had initially been suspected, he was eventually diagnosed with intracranial hypertension after developing ophthalmoplegia and papilledema. We describe the first known instance of successful medical treatment of increased intracranial pressure in a patient with GSD.

18.
Am J Med Genet A ; 170(7): 1780-5, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27112432

RESUMO

Troyer syndrome is a complex hereditary spastic paraplegia (HSP) due to a mutation in SPG20 first reported in the Old Amish population. A genetic mutation in SPG20 is responsible for a loss of function of the protein spartin in this disease. Since its initial report, this syndrome has also been reported in Turkish and Omani families. Here we report the case of three patients of Filipino descent with Troyer syndrome. Whole exome sequencing (WES) identified a homozygous mutation c.364_365delAT which predicts p.Met122Valfs*2 in SPG20. This is the same mutation identified in affected patients from the Omani and Turkish families, and is the first report of this syndrome in the Filipino population. Although Troyer syndrome has characteristic phenotypic manifestations it is likely underdiagnosed due to its rarity and we expect that WES will lead to identifying this disease in other individuals. © 2016 Wiley Periodicals, Inc.


Assuntos
Proteínas/genética , Paraplegia Espástica Hereditária/genética , Proteínas de Ciclo Celular , Criança , Exoma/genética , Feminino , Humanos , Masculino , Mutação , Paraplegia Espástica Hereditária/epidemiologia , Paraplegia Espástica Hereditária/fisiopatologia
19.
Neurol Clin Pract ; 6(4): 339-347, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29443126

RESUMO

PURPOSE OF REVIEW: Tuberous sclerosis complex (TSC) is a variably expressed neurocutaneous genetic disorder characterized by hamartomatous growths in multiple organ systems. Neurologic involvement often confers the most severe symptoms, and can include epilepsy, increased intracranial pressure from hydrocephalus, intellectual deficits, and autism. The purpose of this review is to provide a neurologically focused update in the diagnosis and treatment of these complications in patients with TSC. RECENT FINDINGS: We highlight 5 new areas of understanding in TSC: the neurobiology of TSC and its translation into clinical practice, vigabatrin in the treatment of infantile spasms, the role of tubers and epilepsy surgery, the treatment of subependymal giant cell astrocytomas, and TSC-related neuropsychiatric disorders. SUMMARY: These recent advances in diagnosis and treatment give our patients with TSC and their families hope for the future for improved care and possible preventive cures, to the end goal of improving quality of life.

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