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What particular mechanical properties can be expected for materials composed of interlocked backbones has been a long-standing issue in materials science since the first reports on polycatenane and polyrotaxane in the 1970s1-3. Here we report a three-dimensional porous metal-organic crystal, which is exceptional in that its warps and wefts are connected only by catenation. This porous crystal is composed of a tetragonal lattice and dynamically changes its geometry upon guest molecule release, uptake and exchange, and also upon temperature variation even in a low temperature range. We indented4 the crystal along its a/b axes and obtained the Young's moduli of 1.77 ± 0.16 GPa in N,N-dimethylformamide and 1.63 ± 0.13 GPa in tetrahydrofuran, which are the lowest among those reported so far for porous metal-organic crystals5. To our surprise, hydrostatic compression showed that this elastic porous crystal was the most deformable along its c axis, where 5% contraction occurred without structural deterioration upon compression up to 0.88 GPa. The crystal structure obtained at 0.46 GPa showed that the catenated macrocycles move translationally upon contraction. We anticipate our mechanically interlocked molecule-based design to be a starting point for the development of porous materials with exotic mechanical properties. For example, squeezable porous crystals that may address an essential difficulty in realizing both high abilities of guest uptake and release are on the horizon.
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Ice polymorphs show extraordinary structural diversity depending on pressure and temperature. The behavior of hydrogen-bond disorder not only is a key ingredient for their structural diversity but also controls their physical properties. However, it has been a challenge to determine the details of the disordered structure in ice polymorphs under pressure, because of the limited observable reciprocal space and inaccuracies related to high-pressure techniques. Here, we present an elucidation of the disordered structure of ice VII, the dominant high-pressure form of water, at 2.2 GPa and 298 K, from both single-crystal and powder neutron-diffraction techniques. We reveal the three-dimensional atomic distributions from the maximum entropy method and unexpectedly find a ring-like distribution of hydrogen in contrast to the commonly accepted discrete sites. In addition, total scattering analysis at 274 K clarified the difference in the intermolecular structure from ice VIII, the ordered counterpart of ice VII, despite an identical molecular geometry. Our complementary structure analyses robustly demonstrate the unique disordered structure of ice VII. Furthermore, these findings are related to proton dynamics, which drastically vary with pressure, and will contribute to an understanding of the structural origin of anomalous physical properties of ice VII under pressures.
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Adenocarcinoma, HPV-independent, mesonephric type (hereafter referred to as "mesonephric carcinoma") arising from the cervix is rare, its treatment has not been established, and its sensitivity to chemotherapy has not been fully investigated. Here we report on a 30-year-old female patient who presented at our hospital with a chief complaint of abnormal genital bleeding. We suspected cervical cancer. Based on examination, biopsy, and imaging, she was diagnosed with stage IIA2 adenocarcinoma of the cervix and was scheduled for surgery. Because she had a SARS-COV-2 infection, she was given two courses of paclitaxel-carboplatin (TC) therapy, based on the then-current surgical risk assessment after SARS-COV-2 infection, with a waiting period of at least 8 weeks. The patient was deemed to have a partial response and was treated with paclitaxel and carboplatin, after which she was deemed to have a partial response and underwent total hysterectomy. A diagnosis of stage IIA2 mesonephric carcinoma, ypT1b2N0M0, was made after histopathologic examination of an excised specimen. The patient was treated with 4 additional courses of TC therapy after surgery, and has had no recurrence in 13 months. We report a first case of response to neoadjuvant chemotherapy with TC regimen in a patient with mesonephric carcinoma of the cervix.
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Adenocarcinoma , COVID-19 , Mesonefroma , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Adulto , Carboplatino/uso terapéutico , Terapia Neoadyuvante , Adenocarcinoma/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Mesonefroma/diagnóstico , Mesonefroma/patología , Paclitaxel/uso terapéuticoRESUMEN
Pericytic tumors are subclassified as myopericytomas, myofibromas, angioleiomyomas, and glomus tumors according to the current World Health Organization classification. These pericytic tumors form a continuous morphologic spectrum, including those with combined morphology. However, to our knowledge, no widely accepted criteria for classifying tumors with combined morphology are available. Recent studies have identified platelet-derived growth factor receptor-beta (PDGFRB) gene mutations in a subset of myofibromas, myopericytomas, and myopericytomatoses but not in angioleiomyomas. NOTCH receptor 3 (NOTCH3) mutations have been reported in a subset of infantile myofibromatosis. To assess their potential role in classifying pericytic tumors, we investigated PDGFRB and NOTCH3 mutations in 41 pericytic tumors of variable morphology, including some combined forms. Our results show these mutations to be present in a variety of pericytic tumors, such as myopericytomas (PDGFRB, 3/11; NOTCH3, 4/11), myopericytomatoses (1/2; 1/2), myofibromas (3/6; 0/6), angioleiomyomas (2/13; 3/13), and glomus tumors (5/9; 1/9). Point mutations were identified in 3 tumors in PDGFRB exon 12 (Y562C, S574F, and G576S), 12 tumors in PDGFRB exon 14 (M655I, H657L, and N666K), and 9 tumors in NOTCH3 exon 25 (A1480S/T, D1481N, G1482S, T1490A, E1491K, G1494S, and V1512A). All PDGFRB mutations and NOTCH3 G1482S, T1490A, and G1494S mutations were classified as "deleterious/damaging" by ≥4 of 6 pathogenicity prediction tools in silico. Five-mutation-positive tumors, including 1 myopericytoma-angioleiomyoma, 2 myopericytomatoses-myofibroma, 1 myofibroma-myopericytoma and 1 angioleiomyoma-myopericytoma, were of combined morphology. Therefore, we found PDGFRB and NOTCH3 mutations to be detectable in a much wider variety of pericytic tumors than previously reported and confirmed myopericytomas, myofibromas, angioleiomyomas, and glomus tumors as members harboring PDGFRB or NOTCH3 mutations. Our results thus suggest that PDGFRB or NOTCH3 mutations are not useful for subclassifying members of the pericytic tumor family.
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Angiomioma , Tumor Glómico , Miofibroma , Myopericytoma , Humanos , Myopericytoma/genética , Myopericytoma/patología , Angiomioma/genética , Angiomioma/patología , Tumor Glómico/genética , Tumor Glómico/patología , Miofibroma/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Mutación , Receptor Notch3/genéticaRESUMEN
Above 2 GPa the phase diagram of water simplifies considerably and exhibits only two solid phases up to 60 GPa, ice VII and ice VIII. The two phases are related to each other by hydrogen ordering, with the oxygen sublattice being essentially the same. Here we present neutron diffraction data to 15 GPa which reveal that the rate of hydrogen ordering at the ice VII-VIII transition decreases strongly with pressure to reach timescales of minutes at 10 GPa. Surprisingly, the ordering process becomes more rapid again upon further compression. We show that such an unusual change in transition rate can be explained by a slowing down of the rotational dynamics of water molecules with a simultaneous increase of translational motion of hydrogen under pressure, as previously suspected. The observed cross-over in the hydrogen dynamics in ice is likely the origin of various hitherto unexplained anomalies of ice VII in the 10-15 GPa range reported by Raman spectroscopy, X-ray diffraction, and proton conductivity.
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High-pressure X-ray and neutron diffraction analyses of an ambient-pressure phase (AP) and two high-pressure phases (HP1 and HP2) of ammonia borane (i.e., NH3BH3 and ND3BD3) were conducted to investigate the relationship between their crystal structures and dihydrogen bonds. It was confirmed that the hydrogen atoms in AP formed dihydrogen bonds between adjacent molecules, and the H-H distance between the hydrogen atoms forming this interaction was shorter than 2.4 Å, which was nearly 2 times larger than the van der Waals radius of hydrogen. In the case of half of the hydrogen bonds, a phase transition from AP to the first high-pressure phase (HP1) at â¼1.2 GPa resulted in an increase in the H-H distances, which suggested that the dihydrogen bonds were broken. However, when HP1 was further pressurized to â¼4 GPa, all of the H-H distances became shorter than 2.4 Å again, which implied the occurrence of pressure-induced re-formation of the dihydrogen bonds. It was speculated that the re-formation was consistent with a second-order phase transition suggested in previous studies by Raman spectroscopy and X-ray diffraction measurement. Furthermore, at â¼11 GPa, HP1 transformed to the second high-pressure phase (HP2), and its structure was determined to be P21 (Z = 2). In this phase transition, the inclination of the molecule axis became larger, and the number of types of dihydrogen bonds increased from 6 to 11. At 18.9 GPa, which was close to the upper pressure limit of HP2, the shortest dihydrogen bond decreased to â¼1.65 Å. Additionally, the X-ray diffraction results suggested another phase transition to the third high-pressure phase (HP3) at â¼20 GPa. The outcomes of this study confirmed experimentally for the first time that the structural change under pressure causes the breakage and re-formation of the dihydrogen bonds of NH3BH3.
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Since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, we have established an archive system of livestock and wild animals from the surrounding ex-evacuation zone. Wildlife within the alert zone have been exposed to low-dose-rate (LDR) radiation for a long continuous time. In this study, we analysed the morphological characteristics of the testes and in vitro fertilization (IVF) capacity of cryopreserved sperm of racoons from the ex-evacuation zone of the FDNPP accident. The radioactivity of caesium-137 (137 Cs) was measured by gamma-ray spectrometry, and the measured radioactivity concentration was 300-6,630 Bq/kg in the Fukushima raccoons. Notably, normal spermatogenesis was observed in the seminiferous tubules of the testes, with the germinal epithelium composed of a spermatogenic cell lineage with no evident ultrastructural alterations; freeze-thawing sperm penetration ability was confirmed using the interspecific zona pellucida-free mouse oocytes IVF assays. This study revealed that the chronic and LDR radiation exposure associated with the FDNPP accident had no adverse effect on the reproductive characteristics and functions of male raccoons.
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Radioisótopos de Cesio/efectos adversos , Accidente Nuclear de Fukushima , Mapaches/fisiología , Testículo/efectos de la radiación , Animales , Radioisótopos de Cesio/análisis , Criopreservación/veterinaria , Femenino , Fertilización In Vitro , Especies Introducidas , Japón , Masculino , Ratones Endogámicos ICR , Mapaches/anatomía & histología , Preservación de Semen/veterinaria , Espermatogénesis/efectos de la radiación , Testículo/fisiología , Testículo/ultraestructuraRESUMEN
Seasonally, bred wild mice provide a unique bioresource, with high genetic diversity that differs from wild-derived mice and laboratory mice. This study aimed to establish an alternative superovulation method using wild large Japanese field mice (Apodemus speciosus) as the model species. Specifically, we investigated how the application of inhibin antiserum and equine chorionic gonadotropin (IASe) during both the reproductive and non-reproductive seasons impact the ovulation rate and competence of embryo development after in vitro fertilization (IVF) with fresh and cryopreserved sperm. When the wild mice were superovulated by injecting eCG followed by human chorionic gonadotropin (hCG), few oocytes were collected during the reproductive and non-reproductive seasons. In comparison, the number of ovulated oocytes was dramatically enhanced by the administration of IASe, followed by isolation of ovulated oocytes 24 hr after 30 IU hCG administration. The IVF oocytes that were in vitro cultured (IVC) with medium containing serum further developed to the 2- and/or 4-cell stage using both fresh and frozen-thawed sperm. In conclusion, we successfully established an alternative protocol for collecting ovulated oocytes from wild large Japanese field mice by administering IASe and hCG during both the reproductive and non-reproductive seasons. This study is the first to develop IVF-IVC wild large Japanese field mice beyond the 2- and/or 4-cell stage in vitro using fresh and cryopreserved sperm. This approach could be used in other species of wild or endangered mice to reduce the number of animals used for experiments, or in maintaining stocks of germ cells or embryos.
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Gonadotropina Coriónica/farmacología , Desarrollo Embrionario/efectos de los fármacos , Gonadotropinas Equinas/farmacología , Sueros Inmunes/farmacología , Murinae , Inducción de la Ovulación/veterinaria , Superovulación/efectos de los fármacos , Animales , Criopreservación/veterinaria , Embrión de Mamíferos , Femenino , Fertilización In Vitro/veterinaria , Caballos , Humanos , Inhibinas/antagonistas & inhibidores , Masculino , Oocitos/citología , Preservación de Semen/veterinariaRESUMEN
Pressure-response on the crystal structure of deuterated α-glycine was investigated at room temperature, using powder and single-crystal X-ray diffraction, and powder neutron diffraction measurements under high pressure. No phase change was observed up to 8.7 GPa, although anisotropy of the lattice compressibility was found. No significant changes in the compressibility and the intramolecular distance between non-deuterated α-glycine and deuterated α-glycine were observed. Neutron diffraction measurements indicated the distance of the intermolecular Dâ¯O bond along with the c-axis increased with compression up to 6.4 GPa. The distance of another Dâ¯O bond along with the a-axis decreased with increasing pressure and became the shortest intermolecular hydrogen bond above 3 GPa. In contrast, the lengths of the bifurcated N-Dâ¯O and C-Dâ¯O hydrogen bonds, which are formed between the layers of the α-glycine molecules along the b-axis, decreased significantly with increasing pressure. The decrease of the intermolecular distances resulted in the largest compressibility of the b-axis, compared to the other two axes. The Hirshfeld analysis suggested that the reduction of the void region size, rather than shrinkage of the strong N-Dâ¯O hydrogen bonds, occurred with compression.
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Nefritis Intersticial , Síndrome de Sjögren , Humanos , Riñón , Síndrome de Sjögren/complicacionesRESUMEN
Human earwax consists of wet and dry types. Dry earwax is frequent in East Asians, whereas wet earwax is common in other populations. Here we show that a SNP, 538G --> A (rs17822931), in the ABCC11 gene is responsible for determination of earwax type. The AA genotype corresponds to dry earwax, and GA and GG to wet type. A 27-bp deletion in ABCC11 exon 29 was also found in a few individuals of Asian ancestry. A functional assay demonstrated that cells with allele A show a lower excretory activity for cGMP than those with allele G. The allele A frequency shows a north-south and east-west downward geographical gradient; worldwide, it is highest in Chinese and Koreans, and a common dry-type haplotype is retained among various ethnic populations. These suggest that the allele A arose in northeast Asia and thereafter spread through the world. The 538G --> A SNP is the first example of DNA polymorphism determining a visible genetic trait.
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Transportadoras de Casetes de Unión a ATP/genética , Cerumen/fisiología , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Mapeo Cromosómico , Frecuencia de los Genes , Marcadores Genéticos , Genotipo , Humanos , Datos de Secuencia Molecular , Polimorfismo Genético , Grupos Raciales/genéticaRESUMEN
It is generally believed that ice crystal-to-crystal transitions do not occur below the glass-transition temperature. For instance, under compression, ice I becomes a metastable state but does not transform into other high-pressure ice crystals, and applying excessive pressure ends up causing its collapse into high-density amorphous ice (HDA). Here, we perform molecular dynamics (MD) simulations to demonstrate that a hydrogen-ordered form of cubic ice (ice Ic) transforms to a hydrogen-ordered form of ice IV without yielding HDA. Our comprehensive search for different configurations combined with density functional theory (DFT) calculations indicates that the hydrogen-ordered ice IV formed by compression would be the thermodynamically most stable hydrogen-ordered ice IV configuration. We also predict the phase boundary of hydrogen order-disorder transition of ice IV, which remains unknown in experiments. Our findings suggest that hydrogen ordering enables an immediate transition between ice polymorphs that is impossible when the hydrogens are disordered.
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The odd hydration number has so far been missing in the water-rich magnesium chloride hydrate series (MgCl2·nH2O). In this study, magnesium chloride heptahydrate, MgCl2·7H2O (or MgCl2·7D2O), which forms at high pressures above 2â GPa and high temperatures above 300â K, has been identified. Its structure has been determined by a combination of in-situ single-crystal X-ray diffraction at 2.5â GPa and 298â K and powder neutron diffraction at 3.1â GPa and 300â K. The single-crystal specimen was grown by mixing alcohols to prevent nucleation of undesired crystalline phases. The results show orientational disorder of water molecules, which was also examined using density functional theory calculations. The disorder involves the reconnection of hydrogen bonds, which differs from those in water ice phases and known disordered salt hydrates. Shrinkage by compression occurs mainly in one direction. In the plane perpendicular to this most compressible direction, oxygen and chlorine atoms are in a hexagonal-like arrangement.
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BACKGROUND: Metastatic cardiac tumors are known to occur more frequently than primary cardiac tumors, however, they often remain asymptomatic and are commonly discovered on autopsy. Malignant tumors with a relatively high frequency of cardiac metastasis include mesothelioma, melanoma, lung cancer, and breast cancer, whereas reports of esophageal cancer with cardiac metastasis are rare. CASE SUMMARY: The case of a 60-year-old man who complained of dysphagia is presented. Upper gastrointestinal endoscopy showed a submucosal tumor-like elevated lesion in the esophagus causing stenosis. Contrast-enhanced computed tomography showed left atrial compression due to the esophageal tumor, multiple liver and lung metastases, and a left pleural effusion. Pathological examination of a biopsy specimen from the esophageal tumor showed spindle-shaped cells, raising suspicion of esophageal sarcoma. The disease progressed rapidly, and systemic chemotherapy was deemed necessary, however, due to his poor general condition, administration of cytotoxic agents was considered difficult. Given his high Combined Positive Score, nivolumab was administered, however, the patient soon died from the disease. The autopsy confirmed spindle cell carcinoma (SCC) of the esophagus and cardiac metastasis with similar histological features. Cancer stem cell markers, ZEB1 and TWIST, were positive in both the primary tumor and the cardiac metastasis. CONCLUSION: To the best of our knowledge, there have been no prior reports of cardiac metastasis of esophageal SCC. This case highlights our experience with a patient with esophageal SCC who progressed rapidly and died from the disease, with the autopsy examination showing cardiac metastasis.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Estenosis Esofágica , Neoplasias Cardíacas , Neoplasias Pulmonares , Melanoma , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Cardíacas/diagnóstico por imagen , Miocardio , Homeobox 1 de Unión a la E-Box con Dedos de ZincRESUMEN
Hydrogen bond symmetrisation is the phenomenon where a hydrogen atom is located at the centre of a hydrogen bond. Theoretical studies predict that hydrogen bonds in ice VII eventually undergo symmetrisation upon increasing pressure, involving nuclear quantum effect with significant isotope effect and drastic changes in the elastic properties through several intermediate states with varying hydrogen distribution. Despite numerous experimental studies conducted, the location of hydrogen and hence the transition pressures reported up to date remain inconsistent. Here we report the atomic distribution of deuterium in D2O ice using neutron diffraction above 100 GPa and observe the transition from a bimodal to a unimodal distribution of deuterium at around 80 GPa. At the transition pressure, a significant narrowing of the peak widths of 110 is also observed, attributed to the structural relaxation by the change of elastic properties.
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In the paper by Yamashita et al. [Acta Cryst. (2022), C78, 749-754], an incorrect phrase is updated.
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Ice IV is a metastable high-pressure phase of ice in which the water molecules exhibit orientational disorder. Although orientational ordering is commonly observed for other ice phases, it has not been reported for ice IV. We conducted in situ powder neutron diffraction experiments for DCl-doped D2O ice IV to investigate its hydrogen ordering. We found abrupt changes in the temperature derivative of unit-cell volume, dV/dT, at â¼120 K, and revealed a slightly ordered structure at low temperatures based on the Rietveld method. The occupancy of the D1 site deviates from 0.5 in particular; it increased when samples were cooled at higher pressures and reached 0.174(14) at 2.38 GPa, 58 K. Our results evidence the presence of a low-symmetry hydrogen-ordered state corresponding to ice IV. It seems, however, difficult to experimentally access the completely ordered phase corresponding to ice IV by slow cooling at high pressure.
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The structure of a recently found hyperhydrated form of sodium chloride (NaCl·13H2O and NaCl·13D2O) has been determined by in situ single-crystal neutron diffraction at 1.7â GPa and 298â K. It has large hydrogen-bond networks and some water molecules have distorted bonding features such as bifurcated hydrogen bonds and five-coordinated water molecules. The hydrogen-bond network has similarities to ice VI in terms of network topology and disordered hydrogen bonds. Assuming the equivalence of network components connected by pseudo-symmetries, the overall network structure of this hydrate can be expressed by breaking it down into smaller structural units which correspond to the ice VI network structure. This hydrogen-bond network contains orientational disorder of water molecules in contrast to the known salt hydrates. An example is presented here for further insights into a hydrogen-bond network containing ionic species.
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A new hydrate form of potassium chloride, KCl·H2O, is identified for the first time by in situ single-crystal X-ray diffraction under high pressure. It has a monoclinic structure with lattice parameters of a = 5.687â (7), b = 6.3969â (3), c = 8.447â (3)â Å and ß = 107.08â (8)° at 2.23â (4)â GPa and 295â K. The structure of this hydrate has K-Cl alignments similar to the B1 phase of anhydrous KCl, while water molecules intercalate among the ionic species. The coordination structures of the K and Cl atoms can be regarded as the intermediate states between the B1 and B2 phases of KCl. This finding provides a perspective on the structural interpretation of multicomponent materials and an additional candidate for bound water in salt-water systems under high pressure, such as inside of icy bodies.
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The assembly of donor-acceptor molecules via charge transfer (CT) interactions gives rise to highly ordered nanomaterials with appealing electronic properties. Here, we present the synthesis and bulk co-assembly of pyrene (Pyr) and naphthalenediimide (NDI) functionalized oligodimethylsiloxanes (oDMS) of discrete length. We tune the donor-acceptor interactions by connecting the pyrene and NDI to the same oligomer, forming a heterotelechelic block molecule (NDI-oDMSPyr), and to two separate oligomers, giving Pyr and NDI homotelechelic block molecules (Pyr-oDMS and NDI-oDMS). Liquid crystalline materials are obtained for binary mixtures of Pyr-oDMS and NDI-oDMS, while crystallization of the CT dimers occurred for the heterotelechelic NDI-oDMS-Pyr block molecule. The synergy between crystallization and phase-segregation coupled with the discrete length of the oDMS units allows for perfect order and sharp interfaces between the insulating siloxane and CT layers composed of crystalline CT dimers. We were able to tune the lamellar domain spacing and donor-acceptor CT interactions by applying pressures up to 6 GPa on the material, making the system promising for soft-material nanotechnologies. These results demonstrate the importance of the molecular design to tune the CT interactions and stability of a CT material.