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1.
Nature ; 631(8019): 54-59, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38839966

RESUMEN

Introducing the concept of topology has revolutionized materials classification, leading to the discovery of topological insulators and Dirac-Weyl semimetals1-3. One of the most fundamental theories underpinning topological materials is the Su-Schrieffer-Heeger (SSH) model4,5, which was developed in 1979-decades before the recognition of topological insulators-to describe conducting polymers. Distinct from the vast majority of known topological insulators with two and three dimensions1-3, the SSH model predicts a one-dimensional analogue of topological insulators, which hosts topological bound states at the endpoints of a chain4-8. To establish this unique and pivotal state, it is crucial to identify the low-energy excitations stemming from bound states, but this has remained unknown in solids because of the absence of suitable platforms. Here we report unusual electronic states that support the emergent bound states in elemental tellurium, the single helix of which was recently proposed to realize an extended version of the SSH chain9,10. Using spin- and angle-resolved photoemission spectroscopy with a micro-focused beam, we have shown spin-polarized in-gap states confined to the edges of the (0001) surface. Our density functional theory calculations indicate that these states are attributed to the interacting bound states originating from the one-dimensional array of SSH tellurium chains. Helices in solids offer a promising experimental platform for investigating exotic properties associated with the SSH chain and exploring topological phases through dimensionality control.

2.
Nature ; 613(7944): 479-484, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36653570

RESUMEN

Chiral molecules can exhibit spin-selective charge emission, which is known as chirality-induced spin selectivity1,2. Despite the constituent light elements of the molecules, their spin polarization can approach or even exceed that of typical ferromagnets. This powerful capability may lead to applications in the chiral spintronics2 field. Although the origin of spin selectivity is elusive, two microscopic phenomena have been suggested based on experimental results: effective enhancement of spin-orbit interactions3 and chirality represented by a pair of oppositely polarized spins4,5. However, the hypotheses remain to be verified. Here we report the simultaneous observation of these two phenomena in an organic chiral superconductor by magnetoresistance measurements in the vicinity of the superconducting transition temperature. A pair of oppositely polarized spins is demonstrated by spatially mapping the spin polarity in an electric alternating current excitation. The obtained spin polarization exceeds that of the Edelstein effect6-10 by several orders of magnitude, which indicates an effective enhancement of the spin-orbit interaction. Our results demonstrate a solid-state analogue of spin accumulations assumed for chiral molecules, and may provide clues to the origin of their molecular counterparts. In addition, the innovative capability of spin-current sourcing will invigorate superconducting spintronics research11.

3.
Phys Rev Lett ; 130(11): 111801, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-37001070

RESUMEN

We present the first search for the pair production of dark particles X via K_{L}^{0}→XX with X decaying into two photons using the data collected by the KOTO experiment. No signal was observed in the mass range of 40-110 MeV/c^{2} and 210-240 MeV/c^{2}. This sets upper limits on the branching fractions as B(K_{L}^{0}→XX)<(1-4)×10^{-7} and B(K_{L}^{0}→XX)<(1-2)×10^{-6} at the 90% confidence level for the two mass regions, respectively.

4.
Pediatr Radiol ; 53(13): 2699-2711, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37964037

RESUMEN

Focal skull lesions in children can be diagnostically challenging with a wide variety of potential etiologies. Understanding the diverse pathologies and recognizing their associated clinical and imaging characteristics is crucial for accurate diagnosis and appropriate treatment planning. We review pertinent anatomy of the scalp and calvarium and review different pathologies that can present with focal skull lesions in pediatric patients. These include neoplastic, non-neoplastic tumor-like, congenital, post traumatic, and vascular-associated etiologies. We review the key clinical and imaging features associated with these pathologies and present teaching points to help make the correct diagnosis. It is important for radiologists to be aware of the common and rare etiologies of skull lesions as well as the clinical and imaging characteristics which can be used to develop an accurate differential to ensure a timely diagnosis and initiate appropriate management.


Asunto(s)
Enfermedades Óseas , Cráneo , Niño , Humanos , Imagen por Resonancia Magnética/métodos , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Cráneo/patología , Tomografía Computarizada por Rayos X/métodos , Enfermedades Óseas/diagnóstico por imagen , Enfermedades Óseas/etiología
5.
Curr Opin Rheumatol ; 34(5): 255-261, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35797524

RESUMEN

PURPOSE OF REVIEW: Advances in pathogenesis of chronic recurrent multifocal osteomyelitis in children (CRMO) have shaped therapeutic strategies. The use of whole-body MRI (WBMRI) and improved awareness of CRMO has increased rates and timeliness of CRMO diagnoses. In this review, we highlight the findings from recently published CRMO cohorts and describe the course, complications, and long-term sequalae of CRMO. It is important for clinicians to be aware of the potential for long-term sequelae in order to optimize therapy and avoid complications. RECENT FINDINGS: Despite recent advances in defining disease pathogenesis, children with CRMO continue to suffer from complications and deformities. Involvement of the spine can be asymptomatic and is not as rare as previously suggested. This can result in damaging outcomes, such as vertebral fractures and permanent deformities. A subset of patients has polycyclic disease course and some continue to have active disease for years and well into adulthood, with significant impacts on quality of life. SUMMARY: These recent findings have considerable implication on clinical practice regarding diagnosis, treatment, and monitoring of the disease. Collectively, they support the need for continued monitoring of the disease and screening using comprehensive imaging, such as WBMRI.


Asunto(s)
Osteomielitis , Calidad de Vida , Niño , Enfermedad Crónica , Progresión de la Enfermedad , Humanos , Imagen por Resonancia Magnética , Osteomielitis/complicaciones , Osteomielitis/diagnóstico por imagen , Recurrencia , Columna Vertebral
6.
Hum Reprod ; 37(7): 1423-1430, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35640043

RESUMEN

STUDY QUESTION: Is there a relation between specific Na+/K+ ATPase isoform expression and localization in human blastocysts and the developmental behavior of the embryo? SUMMARY ANSWER: Na+/K+ ATPase α1, ß1 and ß3 are the main isoforms expressed in human blastocysts and no association was found between the expression level of their respective mRNAs and the rate of blastocyst expansion. WHAT IS KNOWN ALREADY: In mouse embryos, Na+/K+ ATPase α1 and ß1 are expressed in the basolateral membrane of trophectoderm (TE) cells and are believed to be involved in blastocoel formation (cavitation). STUDY DESIGN, SIZE, DURATION: A total of 20 surplus embryos from 11 patients who underwent IVF and embryo transfer at a university hospital between 2009 and 2018 were analyzed. PARTICIPANTS/MATERIALS, SETTING, METHODS: After freezing and thawing Day 5 human blastocysts, their developmental behavior was observed for 24 h using time-lapse imaging, and the expression of Na+/K+ ATPase isoforms was examined using quantitative RT-PCR (RT-qPCR). The expressed isoforms were then localized in blastocysts using fluorescent immunostaining. MAIN RESULTS AND THE ROLE OF CHANCE: RT-qPCR results demonstrated the expression of Na+/K+ ATPase α1, ß1 and ß3 isoforms in human blastocysts. Isoforms α1 and ß3 were localized to the basolateral membrane of TE cells, and ß1 was localized between TE cells. A high level of ß3 mRNA expression correlated with easier hatching (P = 0.0261). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: The expression of mRNA and the localization of proteins of interest were verified, but we have not been able to perform functional analysis. WIDER IMPLICATIONS OF THE FINDINGS: Of the various Na+/K+ ATPase isoforms, expression levels of the α1, ß1 and ß3 mRNAs were clearly higher than other isoforms in human blastocysts. Since α1 and ß3 were localized to the basolateral membrane via fluorescent immunostaining, we believe that these subunits contribute to the dilation of the blastocoel. The ß1 isoform is localized between TE cells and may be involved in tight junction formation, as previously reported in mouse embryos. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the JSPS KAKENHI (https://www.jsps.go.jp/english/index.html), grant number 17K11215. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors have no conflicts of interest.


Asunto(s)
Blastocisto , Embrión de Mamíferos , Animales , Blastocisto/metabolismo , Membrana Celular/metabolismo , Embrión de Mamíferos/metabolismo , Humanos , Ratones , ARN Mensajero/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
7.
Phys Rev Lett ; 126(17): 175503, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33988455

RESUMEN

In situ femtosecond x-ray diffraction measurements and ab initio molecular dynamics simulations were performed to study the liquid structure of tantalum shock released from several hundred gigapascals (GPa) on the nanosecond timescale. The results show that the internal negative pressure applied to the liquid tantalum reached -5.6 (0.8) GPa, suggesting the existence of a liquid-gas mixing state due to cavitation. This is the first direct evidence to prove the classical nucleation theory which predicts that liquids with high surface tension can support GPa regime tensile stress.

8.
Phys Rev Lett ; 126(12): 121801, 2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-33834796

RESUMEN

The rare decay K_{L}→π^{0}νν[over ¯] was studied with the dataset taken at the J-PARC KOTO experiment in 2016, 2017, and 2018. With a single event sensitivity of (7.20±0.05_{stat}±0.66_{syst})×10^{-10}, three candidate events were observed in the signal region. After unveiling them, contaminations from K^{±} and scattered K_{L} decays were studied, and the total number of background events was estimated to be 1.22±0.26. We conclude that the number of observed events is statistically consistent with the background expectation. For this dataset, we set an upper limit of 4.9×10^{-9} on the branching fraction of K_{L}→π^{0}νν[over ¯] at the 90% confidence level.

9.
Nature ; 520(7546): 209-11, 2015 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-25855457

RESUMEN

The chemical properties of an element are primarily governed by the configuration of electrons in the valence shell. Relativistic effects influence the electronic structure of heavy elements in the sixth row of the periodic table, and these effects increase dramatically in the seventh row--including the actinides--even affecting ground-state configurations. Atomic s and p1/2 orbitals are stabilized by relativistic effects, whereas p3/2, d and f orbitals are destabilized, so that ground-state configurations of heavy elements may differ from those of lighter elements in the same group. The first ionization potential (IP1) is a measure of the energy required to remove one valence electron from a neutral atom, and is an atomic property that reflects the outermost electronic configuration. Precise and accurate experimental determination of IP1 gives information on the binding energy of valence electrons, and also, therefore, on the degree of relativistic stabilization. However, such measurements are hampered by the difficulty in obtaining the heaviest elements on scales of more than one atom at a time. Here we report that the experimentally obtained IP1 of the heaviest actinide, lawrencium (Lr, atomic number 103), is 4.96(+0.08)(-0.07) electronvolts. The IP1 of Lr was measured with (256)Lr (half-life 27 seconds) using an efficient surface ion-source and a radioisotope detection system coupled to a mass separator. The measured IP1 is in excellent agreement with the value of 4.963(15) electronvolts predicted here by state-of-the-art relativistic calculations. The present work provides a reliable benchmark for theoretical calculations and also opens the way for IP1 measurements of superheavy elements (that is, transactinides) on an atom-at-a-time scale.

10.
Nat Mater ; 18(3): 229-233, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30742081

RESUMEN

Interparticle interactions are self-conflicting rather than cooperative on particular lattices. When such geometrical frustration occurs, charge ordering (CO) can be destabilized into non-trivial charge states such as the recently observed charge glass (CG). A more extreme case is the frustration-induced quantum melting of the CO that has been theoretically proposed. Here, we report d.c. charge transport and noise spectroscopy measurements for a triangular-lattice organic conductor situated close to the CO or CG. Our experiments demonstrate that these materials can host a strange metal with unusual charge dynamics, which we attribute to frustration-induced fluctuations of the CO or CG. Our results also show that the anomalous charge fluctuations can freeze into an insulating state when uniaxial stress is applied, which reduces the geometrical frustration. The present observations suggest the existence of the frustration-induced quantum melting of charges analogous to spin liquids.

11.
Phys Rev Lett ; 124(11): 112501, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32242689

RESUMEN

The gyromagnetic factor of the low-lying E=251.96(9) keV isomeric state of the nucleus ^{99}Zr was measured using the time-dependent perturbed angular distribution technique. This level is assigned a spin and parity of J^{π}=7/2^{+}, with a half-life of T_{1/2}=336(5) ns. The isomer was produced and spin aligned via the abrasion-fission of a ^{238}U primary beam at RIKEN RIBF. A magnetic moment |µ|=2.31(14)µ_{N} was deduced showing that this isomer is not single particle in nature. A comparison of the experimental values with interacting boson-fermion model IBFM-1 results shows that this state is strongly mixed with a main νd_{5/2} composition. Furthermore, it was found that monopole single-particle evolution changes significantly with the appearance of collective modes, likely due to type-II shell evolution.

12.
J Microsc ; 279(3): 234-241, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32043578

RESUMEN

Metallic materials are known to be very sensitive to Gallium (Ga) focused ion beam (FIB) processing. Crystal defects formed by FIB irradiation degrade the transmission electron microscope image quality, and it is difficult to distinguish original defects from FIB process-induced damage. A solution to this problem is the low acceleration voltage and low incident angle (LVLA) Argon ion milling, which can be incorporated as an extensional countermeasure for FIB damage removal and eventually for preparation of high-quality lamellae. The transmission electron microscope image quality of iron single crystal could be improved by removing crystal defects using the low acceleration voltage and low incident angle Argon ion milling finish. Lamella quality of the processing result was almost similar with that of the conventional electrolytic polishing. As a practical application of the process, low damage lamella of stainless cast steel could be prepared. Effectiveness of the FIB system equipped with the low acceleration voltage and low incident angle Argon ion milling function as a tool to make high-quality metallic material lamellae is illustrated.

13.
Eur J Neurol ; 27(12): 2463-2472, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32697875

RESUMEN

BACKGROUND AND PURPOSE: Urinary liver-type fatty-acid binding protein (L-FABP), which is a biomarker of kidney tubule injury, has been studied extensively and established as a risk marker of acute kidney injury (AKI). The aim of this study was to investigate whether kidney tubule injury is associated with the development of AKI and mortality in patients with acute ischaemic stroke. METHODS: Acute ischaemic stroke patients hospitalized in the stroke care unit (SCU) within 24 h after symptom onset were prospectively investigated. AKI was defined on the basis of Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Baseline urinary L-FABP was measured on admission. We evaluated the associations among urinary L-FABP, incidence of AKI, and 90-day mortality adjusted for renal function, albuminuria and other potentially predictive variables, using multivariable analysis. RESULTS: In total, 527 acute ischaemic stroke patients (342 men, median age 74 years) were enrolled in the study. Twenty-seven patients (5.1%) experienced AKI within 7 days of admission. In the univariate analysis, high urinary L-FABP level had positive associations with AKI [53.8 µg/g creatinine (Cr) vs. 3.9 µg/g Cr; P < 0.001] and 90-day mortality (15.5 µg/g Cr vs. 4.0 µg/g Cr; P < 0.001). In the multivariate analysis, elevated urinary L-FABP level (per 10-µg/g Cr increase) was independently associated with AKI (odds ratio 1.225, 95% confidence interval (CI) 1.083-1.454; P = 0.003) and 90-day mortality (hazard ratio 1.091, 95% CI 1.045-1.138; P < 0.001). CONCLUSION: Urinary biomarkers of kidney tubule injury are independently associated with the development of AKI and 90-day mortality in patients with acute ischaemic stroke treated at the SCU.


Asunto(s)
Lesión Renal Aguda , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/etiología , Anciano , Biomarcadores , Isquemia Encefálica/complicaciones , Femenino , Humanos , Túbulos Renales , Masculino
14.
Ann Oncol ; 30(8): 1370-1380, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31150059

RESUMEN

BACKGROUND: Despite the completion of numerous phase II studies, a standard of care treatment has yet to be defined for metastatic uveal melanoma (mUM). To determine benchmarks of progression free survival (PFS) and overall survival (OS), we carried out a meta-analysis using individual patient level trial data. METHODS: Individual patient variables and survival outcomes were requested from 29 trials published from 2000 to 2016. Univariable and multivariable analysis were carried out for prognostic factors. The variability between trial arms and between therapeutic agents on PFS and OS was investigated. RESULTS: OS data were available for 912 patients. The median PFS was 3.3 months (95% CI 2.9-3.6) and 6-month PFS rate was 27% (95% CI 24-30). Univariable analysis showed male sex, elevated (i.e. > versus ≤ upper limit of normal) lactate dehydrogenase (LDH), elevated alkaline phosphatase (ALP) and diameter of the largest liver metastasis (≥3 cm versus <3 cm) to be substantially associated with shorter PFS. Multivariable analysis showed male sex, elevated LDH and elevated ALP were substantially associated with shorter PFS. The most substantial factors associated with 6-month PFS rate, on both univariable and multivariable analysis were elevated LDH and ALP. The median OS was 10.2 months (95% CI 9.5-11.0) and 1 year OS was 43% (95% CI 40-47). The most substantial prognostic factors for shorter OS by univariable and multivariable analysis were elevated LDH and elevated ALP. Patients treated with liver directed treatments had statistically significant longer PFS and OS. CONCLUSION: Benchmarks of 6-month PFS and 1-year OS rates were determined accounting for prognostic factors. These may be used to facilitate future trial design and stratification in mUM.


Asunto(s)
Ensayos Clínicos como Asunto/normas , Neoplasias Hepáticas/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Proyectos de Investigación/estadística & datos numéricos , Neoplasias de la Úvea/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fosfatasa Alcalina/sangre , Benchmarking , Conjuntos de Datos como Asunto , Femenino , Humanos , Estimación de Kaplan-Meier , L-Lactato Deshidrogenasa/sangre , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/secundario , Masculino , Melanoma/sangre , Melanoma/mortalidad , Melanoma/patología , Persona de Mediana Edad , Pronóstico , Supervivencia sin Progresión , Estudios Prospectivos , Factores Sexuales , Factores de Tiempo , Neoplasias de la Úvea/sangre , Neoplasias de la Úvea/mortalidad , Neoplasias de la Úvea/patología , Adulto Joven
15.
Phys Rev Lett ; 122(2): 021802, 2019 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-30720307

RESUMEN

A search for the rare decay K_{L}→π^{0}νν[over ¯] was performed. With the data collected in 2015, corresponding to 2.2×10^{19} protons on target, a single event sensitivity of (1.30±0.01_{stat}±0.14_{syst})×10^{-9} was achieved and no candidate events were observed. We set an upper limit of 3.0×10^{-9} for the branching fraction of K_{L}→π^{0}νν[over ¯] at the 90% confidence level (C.L.), which improved the previous limit by almost an order of magnitude. An upper limit for K_{L}→π^{0}X^{0} was also set as 2.4×10^{-9} at the 90% C.L., where X^{0} is an invisible boson with a mass of 135 MeV/c^{2}.

16.
Phys Rev Lett ; 122(19): 192501, 2019 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-31144924

RESUMEN

We present a precision analysis of the ^{136}Xe two-neutrino ßß electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ßß rate allows us to measure the ratio of the leading and subleading 2νßß nuclear matrix elements (NMEs), ξ_{31}^{2ν}=-0.26_{-0.25}^{+0.31}. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ_{31}^{2ν} range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ_{31}^{2ν} values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ßß decay, ξ_{31}^{2ν} provides new insights toward reliable neutrinoless ßß NMEs.

17.
Lupus ; 28(13): 1577-1582, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31635559

RESUMEN

OBJECTIVE: The objective of this study was to clarify the efficacy and safety of factor Xa inhibitors for antiphospholipid syndrome patients in real world utilization. METHODS: This is a retrospective cohort study comprised of all consecutive patients with antiphospholipid syndrome in our department over a period of 28 years. Patients treated with factor Xa inhibitors were extracted from the cohort. As a control group, patients treated with warfarin were selected from the same cohort with matched age, gender, coexistence of systemic lupus erythematosus, and the presence of antiplatelet therapy, after which we used a propensity score for each of the risk factors as an additional covariate in multivariate Cox proportional hazard regression. The primary endpoint was set as thrombotic and hemorrhagic event-free survival for five years. RESULTS: Among 206 patients with antiphospholipid syndrome, 18 had a history of anti-Xa therapy (five rivaroxaban, 12 edoxaban, one apixaban). Fourteen out of 18 patients on anti-Xa therapy had switched to factor Xa inhibitors from warfarin. Event-free survival was significantly shorter during anti-Xa therapy than that during warfarin therapy (hazard ratio: 12.1, 95% confidence interval: 1.73-248, p = 0.01) ( Figure 1(a) ). Similarly, event-free survival in patients treated with factor Xa inhibitors was significantly shorter compared with controls (hazard ratio: 4.62, 95% confidence interval: 1.54-13.6, p = 0.0075). In the multivariate Cox proportional hazard model, event-free survival in patients with anti-Xa therapy remained significantly shorter (hazard ratio: 11.9, 95% confidence interval: 2.93-56.0, p = 0.0005). CONCLUSIONS: Factor Xa inhibitors may not be recommended for antiphospholipid syndrome.


Asunto(s)
Síndrome Antifosfolípido/tratamiento farmacológico , Inhibidores del Factor Xa/administración & dosificación , Trombosis/prevención & control , Adulto , Síndrome Antifosfolípido/complicaciones , Estudios de Cohortes , Inhibidores del Factor Xa/efectos adversos , Femenino , Hemorragia/inducido químicamente , Humanos , Estudios Longitudinales , Lupus Eritematoso Sistémico/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trombosis/etiología
18.
BJOG ; 126(12): 1448-1454, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31386246

RESUMEN

OBJECTIVE: To examine the association between maternal alcohol consumption during pregnancy and the risk of preterm delivery. DESIGN: Prospective cohort study. SETTING: The Japan Environment and Children's Study (JECS). POPULATION: A total of 94 349 singleton pregnancies. METHODS: Participants completed questionnaires detailing alcohol consumption during the first trimester and during the second and third trimesters. Participants were divided into four categories according to alcohol consumption (non-drinkers, consumers of 1-149 g, 150-299 g and ≥300 g ethanol/week). We examined the effect of alcohol consumption during different stages of pregnancy on the risk of preterm delivery. Odds ratios (OR) and 95% CI were calculated relative to non-drinkers using logistic regression. MAIN OUTCOME MEASURES: Medical record-based preterm delivery. RESULTS: Alcohol consumption during the second and third trimesters, but not during the first trimester, was associated with increased risk of preterm delivery. Heavy alcohol consumption (≥300 g ethanol/week) during the second and third trimesters was associated with a four-fold higher risk compared with non-drinkers (multivariable OR 4.52; 95% CI 1.68-12.2). Light alcohol consumption (1-149 g ethanol/week) tended to be associated with lower risk of preterm delivery (multivariable OR 0.78; 95% CI 0.60-1.00). CONCLUSIONS: Heavy alcohol consumption during the second and third trimesters was associated with increased risk of preterm delivery among pregnant women. TWEETABLE ABSTRACT: Heavy drinking during pregnancy may increase the risk of preterm delivery.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Nacimiento Prematuro/epidemiología , Adulto , Estudios de Cohortes , Femenino , Humanos , Japón/epidemiología , Servicios de Salud Materno-Infantil , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Nacimiento Prematuro/etiología , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios
19.
Radiographics ; 39(7): 2085-2102, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31697622

RESUMEN

The neural crest is an important transient structure that develops during embryogenesis in vertebrates. Neural crest cells are multipotent progenitor cells that migrate and develop into a diverse range of cells and tissues throughout the body. Although neural crest cells originate from the ectoderm, they can differentiate into mesodermal-type or endodermal-type cells and tissues. Some of these tissues include the peripheral, autonomic, and enteric nervous systems; chromaffin cells of the adrenal medulla; smooth muscles of the intracranial blood vessels; melanocytes of the skin; cartilage and bones of the face; and parafollicular cells of the thyroid gland. Neurocristopathies are a group of diseases caused by the abnormal generation, migration, or differentiation of neural crest cells. They often involve multiple organ systems in a single person, are often familial, and can be associated with the development of neoplasms. As understanding of the neural crest has advanced, many seemingly disparate diseases, such Treacher Collins syndrome, 22q11.2 deletion syndrome, Hirschsprung disease, neuroblastoma, neurocutaneous melanocytosis, and neurofibromatosis, have come to be recognized as neurocristopathies. Neurocristopathies can be divided into three main categories: dysgenetic malformations, neoplasms, and combined dysgenetic and neoplastic syndromes. In this article, neural crest development, as well as several associated dysgenetic, neoplastic, and combined neurocristopathies, are reviewed. Neurocristopathies often have clinical manifestations in multiple organ systems, and radiologists are positioned to have significant roles in the initial diagnosis of these disorders, evaluation of subclinical associated lesions, creation of treatment plans, and patient follow-up. Online supplemental material is available for this article. ©RSNA, 2019.


Asunto(s)
Anomalías Congénitas/embriología , Neoplasias/embriología , Cresta Neural/patología , Síndrome de Deleción 22q11/diagnóstico por imagen , Síndrome de Deleción 22q11/embriología , Anomalías Múltiples/diagnóstico por imagen , Anomalías Múltiples/embriología , Síndrome CHARGE/diagnóstico por imagen , Síndrome CHARGE/embriología , Linaje de la Célula , Movimiento Celular , Anomalías Congénitas/diagnóstico por imagen , Enfermedades en Gemelos , Desarrollo Embrionario , Síndrome de Goldenhar/diagnóstico por imagen , Síndrome de Goldenhar/embriología , Enfermedad de Hirschsprung/diagnóstico por imagen , Enfermedad de Hirschsprung/embriología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Disostosis Mandibulofacial/diagnóstico por imagen , Disostosis Mandibulofacial/embriología , Neoplasias/diagnóstico por imagen , Síndromes Neoplásicos Hereditarios/diagnóstico por imagen , Síndromes Neoplásicos Hereditarios/embriología , Cresta Neural/embriología , Neuroblastoma/diagnóstico por imagen , Neuroblastoma/embriología , Síndromes Neurocutáneos/diagnóstico por imagen , Síndromes Neurocutáneos/embriología , Nevo Pigmentado/diagnóstico por imagen , Nevo Pigmentado/embriología , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/embriología , Tomografía Computarizada por Rayos X
20.
Stud Mycol ; 92: 1-46, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29997400

RESUMEN

Although Glomerella glycines, Colletotrichum magnum and C. orchidearum are known as causal agents of anthracnose of soybean, Cucurbitaceae and Orchidaceae, respectively, their taxonomy remains unresolved. In preliminary analyses based on ITS, strains of these species appear basal in Colletotrichum phylogenies, clustering close to C. cliviae, C. brevisporum and other recently described species from tropical or subtropical regions. Phylogenetic analyses (ITS, GAPDH, CHS-1, HIS3, ACT, TUB2) of 102 strains previously identified as Ga. glycines, C. magnum and C. orchidearum as well as other related strains from different culture collections and studies placed these taxa in three species complexes, and distinguished at least 24 species, including 11 new species. In this study, C. magnum, C. orchidearum and C. piperis were epitypified and their taxonomy resolved, while C. cliviicola was proposed as a new name for C. cliviae. Furthermore, a sexual morph was observed for C. yunnanense, while C. brevisporum, C. cliviicola and C. tropicicola were reported from new hosts or countries. Regarding their conidial morphology, species in the C. dracaenophilum, C. magnum and C. orchidearum species complexes are reminiscent of C. gloeosporioides or C. boninense s. lat., and were likely to be confused with them in the past.

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