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1.
Nano Lett ; 23(10): 4533-4540, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37155295

RESUMEN

Janus transition metal dichalcogenides (TMDCs), with dissimilar chalcogen atoms on each side of TMDCs, have garnered considerable research attention because of the out-of-plane intrinsic polarization in monolayer TMDCs. Although a plasma process has been proposed for synthesizing Janus TMDCs based on the atomic substitution of surface atoms at room temperature, the formation dynamics and intermediate electronic states have not been completely examined. In this study, we investigated the intermediate state between MoSe2 and Janus MoSeS during plasma processing. Atomic composition analysis and atomic-scale structural observations revealed the intermediate partially substituted Janus (PSJ) structure. Combined with theoretical calculations, we successfully clarified the characteristic Raman modes in the intermediate PSJ structure. The PL exhibited discontinuous transitions that could not be explained by the theoretical calculations. These findings will contribute toward understanding the formation process and electronic-state modulation of Janus TMDCs.

2.
J Phys Ther Sci ; 36(4): 167-174, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38562533

RESUMEN

[Purpose] This study was aimed at evaluating the clinical indicators for predicting ambulation at 3 months after putaminal hemorrhage. [Participants and Methods] The participants were 84 inpatients with putaminal hemorrhage. The patients' background characteristics and computed tomography findings at the time of the onset of putaminal hemorrhage were obtained from their medical records. Impaired consciousness, severity of hemiplegia, higher brain dysfunction, sensory impairment, activities of daily living, and ambulatory ability were evaluated. Logistic regression analysis was performed to identify factors associated with ambulation at 3 months, and receiver operating characteristic curve analysis was conducted to determine the predictive value of the identified factors and the optimal cut-off values. [Results] Ventricular rupture, severity of hemiplegia (determined using the 12-grade hemiplegia function test), and Functional Independence Measure cognitive score were found to be independent predictors of prognosis. Severity of hemiplegia was the strongest predictor of ambulation, with a sensitivity of 80.4% and specificity of 100% when the cut-off was set at grade 6 (the ability for coordinated movement of the extensor and flexor muscles of the hip joint). [Conclusion] The severity of hemiplegia, Functional Independence Measure cognitive score, and ventricular rupture were independently associated with ambulation in patients with putaminal hemorrhage. The ability of the hip joint movement is one of the most important factors in ambulation prognosis.

3.
Heart Vessels ; 38(9): 1149-1155, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37029247

RESUMEN

Progression from paroxysmal to persistent atrial fibrillation (AF) is occasionally encountered in patients with previous pacemaker implantation (PMI) for the treatment of tachycardia-bradycardia syndrome (TBS). We aimed to determine the rate of its incidence occurring within the early years after PMI and the predictors. We studied TBS patients who received PMI at 5 core cardiovascular centers. The end point was a conversion from paroxysmal to persistent AF. We extracted 342 TBS patients out of 2579 undergoing PMI. During 5 ± 3.1 years of follow-up, 114 (33.3%) reached the end point. The time to the end point was 2.9 ± 2.7 years. The event rates within a year and 3 years after the PMI were 8.8% and 19.6%, respectively. In the multivariate hazard analyses, hypertension (hazard ratio [HR] 3.2, P = 0.03) and congestive heart failure (HR 2.1, P = 0.04) were found to be independent predictors of the end point occurring within a year after the PMI. Congestive heart failure (HR 1.82, P = 0.04), left atrial diameter of ≥ 40 mm (HR 4.55, P < 0.001), and the use of antiarrhythmic agents (HR 0.58, P = 0.04) were independently associated with the 3-year end point. Prediction models including combinations of those 4 parameters for the 1- and 3-year incidence both exhibited a modest risk discrimination (both c-statistics 0.71). In conclusion, early progression from paroxysmal to persistent AF was less frequent than expected in the TBS patients with PMI. Factors related to atrial remodeling and no use of antiarrhythmic drugs may facilitate the progression.


Asunto(s)
Fibrilación Atrial , Marcapaso Artificial , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Fibrilación Atrial/terapia , Bradicardia , Síndrome del Seno Enfermo , Antiarrítmicos/uso terapéutico , Taquicardia/diagnóstico , Taquicardia/epidemiología , Taquicardia/terapia , Resultado del Tratamiento
4.
BMC Med Imaging ; 23(1): 188, 2023 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978440

RESUMEN

BACKGROUND: Although it is generally thought that disturbance of perfusion in the anterior lobe of the pituitary gland leads to complete or partial hypopituitarism, the gadolinium (Gd) enhancement findings on Magnetic Resonance Imaging (MRI) of patients with growth hormone deficiency (GHD) remain unknown. The purpose of this study was to compare Gd enhancement of the pituitary gland on MRI of patients with GHD to that of healthy subjects. METHODS: In this retrospective study, we analyzed the data of 10 patients with clinically diagnosed GHD who underwent Gd-enhanced MRI of their pituitaries (age 8.3[Formula: see text]3.5 year, female 1, males 9), together with data of 5 patients with clinically normal growth hormone (GH) dynamics who also underwent Gd-enhanced pituitary MRI (age 6.2[Formula: see text]3.4 year, female 4, males 1). In each subject, a maximum-diameter region of interest (ROI) was drawn on the anterior pituitary gland of post Gd-enhanced coronal T1-weighted images, and the signal intensity ratio of the anterior pituitary gland to the white matter on the right temporal lobe of the same cross section was assessed. RESULTS: The mean area of the ROI in the anterior pituitary gland and white matter of temporal lobe on the same cross section showed no significant differences between patients with GHD and those with normal GH (pituitary, 17.43 mm2[Formula: see text]8.24 vs. 21.08 mm2[Formula: see text]10.40, p = 1.00; white matter, 74.47mm2[Formula: see text]24.19 and 62.50 mm2[Formula: see text]17.90, p = 0.37), suggesting that the sizes of the pituitary glands were comparable. The ratios of Gd enhancement in the anterior pituitary gland showed significant differences between GHD and normal-GH subjects ([Formula: see text][Formula: see text]0.68[Formula: see text]0.26 vs.[Formula: see text]0.16, p= 0.04). CONCLUSIONS: These results suggested that the contrast effect on Gd-enhanced MRI is attenuated in the pituitary glands of patients with GHD compared to those with normal GH. These new clinical findings regarding Gd-enhanced MRI can assist the diagnosis of pediatric GHD.


Asunto(s)
Hormona de Crecimiento Humana , Hipopituitarismo , Masculino , Niño , Humanos , Femenino , Medios de Contraste , Gadolinio , Estudios Retrospectivos , Hipófisis/diagnóstico por imagen , Hipopituitarismo/diagnóstico , Imagen por Resonancia Magnética , Hormona del Crecimiento
5.
Chemistry ; 28(26): e202104316, 2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35253943

RESUMEN

Two-dimensional (2D) hybrid perovskites with novel functionalities and structural diversity are a perfect platform for emerging optoelectronic devices such as photodetectors, light-emitting diodes, and solar cells. Here, we demonstrate that excess concentration of Cesium bromide (CsBr) is key to the formation of easily exfoliated 2D Cs2 Cu(Cl/Br)4 perovskite crystal. Furthermore, by employing this trick to 2D perovskite MA2 Cu(Cl/Br)4 (MA=methylammonium), we achieve a phase-pure easily exfoliated 2D mixed-cation (MA/Cs)2 Cu(Cl/Br)4 perovskite crystal, which exhibits reduced bandgap (1.53 eV) with ferromagnetic behavior and photovoltaic property. The resultant mixed-cation structured device reveals enhanced efficiency compared to all MA and all Cs counterparts. These findings demonstrate the importance of cation-engineering in developing innovative materials with novel properties.

6.
Nanotechnology ; 33(23)2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35196260

RESUMEN

Carbon nanotubes (CNTs) exhibit extremely high nanoscopic thermal/electrical transport and mechanical properties. However, the macroscopic properties of assembled CNTs are significantly lower than those of CNTs because of the boundary structure between the CNTs. Therefore, it is crucial to understand the relationship between the nanoscopic boundary structure in CNTs and the macroscopic properties of the assembled CNTs. Previous studies have shown that the nanoscopic phonon transport and macroscopic thermal transport in CNTs are improved by Joule annealing because of the improved boundary Van-der-Waals interactions between CNTs via the graphitization of amorphous carbon. In this study, we investigate the mechanical strength and thermal/electrical transport properties of CNT yarns with and without Joule annealing at various temperatures, analyzing the phenomena occurring at the boundaries of CNTs. The obtained experimental and theoretical results connect the nanoscopic boundary interaction of CNTs in CNT yarns and the macroscopic mechanical and transport properties of CNT yarns.

7.
Childs Nerv Syst ; 38(2): 485-489, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34837501

RESUMEN

INTRODUCTION: Traumatic retroclival epidural hematoma is rare. It is more common in pediatrics than in adults. Although it has been known that these cases are frequently associated with abducens nerve palsy, internal carotid artery stenosis is rarely found with those hematomas. CASE REPORT: An 8-year-old girl was transferred to our hospital following a traffic accident. She had clear consciousness with right abducens nerve palsy. Computed tomography revealed the left side of both retroclival hematoma without clival fracture and subarachnoid hemorrhage at the Sylvian fissure. She also had a fracture of left femoral neck and ipsilateral lung contusion. Magnetic resonance imaging revealed a retroclival hematoma located in the epidural space and severe stenosis of left internal carotid artery (ICA) from the cavernous to supraclinoid portion without evidence of brain contusion. She was managed conservatively, and her right abducens nerve palsy recovered completely without deterioration of other neurological findings. Neuroradiological findings suggested this ICA stenosis as traumatic dissection. She was discharged home 2 months after the traffic accident. CONCLUSION: Retroclival epidural hematoma without clival fracture associated with ipsilateral ICA stenosis is extremely rare. Although the exact mechanism of the ICA stenosis remains unclear, cerebral vascular events should be considered in the cases with traumatic retroclival hematoma.


Asunto(s)
Estenosis Carotídea , Hematoma Epidural Craneal , Hematoma Espinal Epidural , Adulto , Arteria Carótida Interna/diagnóstico por imagen , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Niño , Femenino , Hematoma Epidural Craneal/complicaciones , Hematoma Epidural Craneal/etiología , Hematoma Espinal Epidural/complicaciones , Humanos , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X
8.
Int J Mol Sci ; 23(21)2022 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-36361987

RESUMEN

In rodent models, leukemia inhibitory factor (LIF) is involved in cerebral development via the placenta, and maternal immune activation is linked to psychiatric disorders in the child. However, whether LIF acts directly on neural progenitor cells (NPCs) remains unclear. This study performed DNA microarray analysis and quantitative RT-PCR on the fetal cerebrum after maternal intraperitoneal or fetal intracerebral ventricular injection of LIF at day 14.5 (E14.5) and determined that the expression of insulin-like growth factors (IGF)-1 and -2 was induced by LIF. Physiological IGF-1 and IGF-2 levels in fetal cerebrospinal fluid (CSF) increased from E15.5 to E17.5, following the physiological surge of LIF levels in CSF at E15.5. Immunostaining showed that IGF-1 was expressed in the cerebrum at E15.5 to E19.5 and IGF-2 at E15.5 to E17.5 and that IGF-1 receptor and insulin receptor were co-expressed in NPCs. Further, LIF treatment enhanced cultured NPC proliferation, which was reduced by picropodophyllin, an IGF-1 receptor inhibitor, even under LIF supplementation. Our findings suggest that IGF expression and release from the NPCs of the fetal cerebrum in fetal CSF is induced by LIF, thus supporting the involvement of the LIF-IGF axis in cerebral cortical development in an autocrine/paracrine manner.


Asunto(s)
Cerebro , Factor Inhibidor de Leucemia , Células-Madre Neurales , Somatomedinas , Animales , Femenino , Embarazo , Ratas , Proliferación Celular , Cerebro/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/metabolismo , Factor Inhibidor de Leucemia/metabolismo , Células-Madre Neurales/metabolismo , Receptor IGF Tipo 1/metabolismo
9.
No Shinkei Geka ; 50(2): 276-286, 2022 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-35400646

RESUMEN

Water not only exists in the ventricles and cisterns but is also contained in the cerebral parenchyma. Water movement in most tissues has been described to be mediated by water channels since the discovery of these channels(aquaporins: AQPs). As to the intracranial situation, AQP-1 is abundantly expressed in the epithelial cells of the choroid plexus. AQP-4 is also enriched in the ependyma, endfeet of astrocytes at the blood-brain barrier, and glia limitans. AQP-4 is involved in cerebrospinal fluid(CSF)absorption, while AQP-1 is involved in CSF production. Impairment of CSF absorption through AQP-4 is considered to be caused by an inflammatory mechanism and finally leads to the development of hydrocephalus. Recently, the glymphatic system was recognized as an intracranial lymphatic system and hypothesized to be involved in CSF absorption and waste removal into the CSF. Disturbances of this glymphatic system may induce Alzheimer's disease and idiopathic normal-pressure hydrocephalus. Although the mechanism of CSF production in the epithelial cells of the choroid plexus remains to be elucidated, the existence of glycolysis leading to the facilitation of AQP-1 expression is considered a key point in CSF production.


Asunto(s)
Acuaporinas , Hidrocefalia , Acuaporinas/metabolismo , Ventrículos Cerebrales , Líquido Cefalorraquídeo , Plexo Coroideo/metabolismo , Humanos , Hidrocefalia/cirugía , Agua/metabolismo
10.
Pituitary ; 24(5): 778-786, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34009499

RESUMEN

PURPOSE: Thyrotropin-secreting pituitary adenoma (TSHoma) is rare but occasionally causes cardiovascular complications such as atrial fibrillation (AF) due to hyperthyroidism. Graves' disease (GD) is a common hyperthyroid condition often associated with subclinical AF. Some reports have shown echocardiographic changes in patients with GD. We aimed to evaluate the preoperative cardiac function in patients with TSHomas and compared the results among patients with TSHomas and GD and control subjects. METHODS: Patients with TSHomas (n = 6) and GD (n = 20) were compared with control subjects with normal cardiac function (n = 20) based on echocardiographic findings. The average age, sex, and proportions of patients with a history of diabetes mellitus and hypertension were equal in each group, and the AF prevalence was matched in patients with TSHomas and GD. The values of left ventricular end-diastolic diameter (LVEDd), left ventricular end-systolic diameter (LVEDs), left ventricular ejection fraction (LVEF), and left atrial diameter (LAD) were used to assess cardiac function. RESULTS: In echocardiography, LAD showed a significant difference between patients with TSHomas and control subjects (p = 0.026). The mean LAD values were 36.9 ± 7.1, 38.2 ± 8.9, and 28.7 ± 3.9 mm for patients with TSHomas and GD and control subjects, respectively. There were no significant differences in other echocardiographic parameters among the groups. Before treatment, serum thyroid hormone levels (free triiodothyronine and thyroxin) were not significantly different among patients with TSHomas and GD. CONCLUSION: We found that patients with TSHomas or GD had enlarged LADs. This finding suggests that AF may be more hidden in patients with TSHomas than previously reported.


Asunto(s)
Fibrilación Atrial , Neoplasias Hipofisarias , Ecocardiografía , Humanos , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/diagnóstico por imagen , Volumen Sistólico , Tirotropina , Función Ventricular Izquierda
11.
Acta Neurochir (Wien) ; 163(2): 383-389, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33128620

RESUMEN

PURPOSE: Oculomotor nerve palsy (ONP) occasionally occurs in cases of pituitary apoplexy (PA) associated with pituitary adenoma, but its mechanism remains unclear. Intracranial nerves are clearly visualized by fast-imaging employing with steady-state acquisition (FIESTA). Here, we assessed the oculomotor nerve compression in patients with PA associated with pituitary adenoma using FIESTA. METHODS: Twenty-eight cases of PA, with or without ONP, were retrospectively reviewed. All patients had undergone preoperative FIESTA. Two neuroradiologists, unaware of the patient's clinical symptoms, evaluated the presence and location of oculomotor nerve compression due to the tumor. RESULTS: Thirteen of the twenty-eight PA cases were associated with ONP. Tumor size and degree of cavernous sinus invasion were not significantly different between the ONP and non-ONP groups. Even in the ONP group, 8/13 (62%) tumors did not show cavernous sinus invasion. Via FIESTA, the presence of oculomotor nerve compression was confirmed in 11/13 (85%) and 5/15 (33%) cases in the ONP and non-ONP groups, respectively (p = 0.008). The radiologists' diagnoses of laterality of nerve compression (right or left) were consistent with the patient's affected eye. In the ONP group, the location of the nerve compression was located at the entry point to the cavernous sinus, the so-called oculomotor triangle, in 9/11 (82%) cases and intra cavernous sinus in 2/11 (18%) cases. CONCLUSION: Compression at the oculomotor triangle is considered the main cause of ONP with PA in pituitary adenomas.


Asunto(s)
Adenoma/complicaciones , Enfermedades del Nervio Oculomotor/diagnóstico por imagen , Enfermedades del Nervio Oculomotor/etiología , Apoplejia Hipofisaria/diagnóstico por imagen , Apoplejia Hipofisaria/etiología , Neoplasias Hipofisarias/complicaciones , Adulto , Anciano , Seno Cavernoso/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nervio Oculomotor , Radiografía , Estudios Retrospectivos
12.
Br J Neurosurg ; : 1-4, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33605824

RESUMEN

Background: Although generally a safe procedure, serious postoperative complications after endoscopic third ventriculostomy (ETV) for obstructive hydrocephaly have been rarely reported, such as delayed obstruction of the stoma at the third ventricle floor.Case description: A 20-year-old male was referred to our department because of severe headache and diplopia. A pineal tumour and obstructive hydrocephaly were detected in preoperative imaging. After tumour biopsy and ETV, the reduction of ventricle size and improvement of headaches were immediately observed. On the seventh day, however, he developed a rapidly progressing consciousness disturbance due to severe hydrocephalus leading to urgent secondary ETV. The original ventriculostomy stoma at the third ventricle floor was completely occluded by scar adhesion. The patient recovered well as previously and received additional treatment.Conclusion: Although very rare, occlusion of the ventriculostomy stoma can postoperatively occur in the subacute period. Patients undergoing ETV for obstructive hydrocephalus due to a pineal tumour should be carefully monitored to avoid serious consequences.

13.
J Chem Phys ; 152(8): 084704, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32113336

RESUMEN

Lead halide perovskites are promising materials for optoelectronic applications because of their exceptional performances in carrier lifetime and diffusion length; however, the microscopic origins of their unique characteristics remain elusive. The organic-inorganic hybrid perovskites show unique dielectric functions, i.e., ferroelectric-like phonon responses in the 0.1-10 THz region and liquid-like rotational relaxation in the 1-100 GHz range. To reveal the role of the dielectric responses is of primal importance because the dielectric screening is a key to understanding the optoelectronic properties governed by polarons in the perovskites. Here, we conducted comparative studies of broadband dielectric spectroscopy on both all-inorganic CsPbBr3 and organic-inorganic hybrid (CH3NH3)PbBr3 single crystals to uncover the origin of the liquid-like dielectric relaxation in the 1-100 GHz range. We confirmed the absence of the dielectric response in the range of 106-1010 Hz in CsPbBr3, which was clearly present in the hybrid (CH3NH3)PbBr3. This suggests that the response is almost purely due to the rotational motions of the organic dipoles in the hybrid perovskites. We evaluated the lifetimes of the polarons using surface-free transient photoluminescence. The lifetime in CsPbBr3 was up to 1.6 µs, while the lifetime in (CH3NH3)PbBr3 was 18 µs. The lifetime in the hybrid (CH3NH3)PbBr3 was significantly longer than in CsPbBr3, also confirmed by transient infrared spectroscopy. We concluded that the liquid-like dielectric response inhibits polaron recombination due to the efficient separation of opposite charges by the additional dynamic disorder.

14.
Molecules ; 25(5)2020 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-32143351

RESUMEN

Carbon nanotube yarns (CNY) are a novel carbonaceous material and have received a great deal of interest since the beginning of the 21st century. CNY are of particular interest due to their useful heat conducting, electrical conducting, and mechanical properties. The electrical conductivity of carbon nanotube yarns can also be influenced by functionalization and annealing. A systematical study of this post synthetic treatment will assist in understanding what factors influences the conductivity of these materials. In this investigation, it is shown that the electrical conductivity can be increased by a factor of 2 and 5.5 through functionalization with acids and high temperature annealing respectively. The scale of the enhancement is dependent on the reducing of intertube space in case of functionalization. For annealing, not only is the highly graphitic structure of the carbon nanotubes (CNT) important, but it is also shown to influence the residual amorphous carbon in the structure. The promising results of this study can help to utilize CNY as a replacement for common materials in the field of electrical wiring.


Asunto(s)
Nanotubos de Carbono/química , Conductividad Eléctrica , Nanotecnología/métodos
15.
Catheter Cardiovasc Interv ; 93(6): 1025-1032, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30723999

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the impact of the J-CTO score on long-term target lesion revascularization (TLR) after successful native chronic total occlusion (CTO)-percutaneous coronary intervention (PCI). BACKGROUND: We previously reported that the J-CTO score could be used to stratify the lesion complexity and procedural success rate in CTO lesions. METHODS: We evaluated the prognostic significance of a high J-CTO score for long-term TLR rate in the J-CTO Registry. RESULTS: In the 425 lesions of 408 patients who underwent successful CTO-PCI during a median follow-up of 63.0 (interquartile range: 21.2-72.9) months in the J-CTO Registry, the cumulative incidence of TLR of lesions with a J-CTO score ≥ 2 (n = 216) was significantly higher than in those with a J-CTO score ≤ 1 (n = 209) (27.0 versus 19.4% at 5 years, respectively, P = 0.04). Among 323 lesions of 309 patients with a complete 5-year follow-up, the rate of TLR was 28% (n = 91). A J-CTO score ≥ 2 was independently associated with a higher risk of TLR (odds ratio, 1.73; 95% confidence interval, 1.01-2.99, P = 0.048) even after adjustment for clinically relevant baseline factors. CONCLUSIONS: Patients with high J-CTO score lesions had a higher 5-year risk of TLR.


Asunto(s)
Angiografía Coronaria , Oclusión Coronaria/terapia , Técnicas de Apoyo para la Decisión , Intervención Coronaria Percutánea , Anciano , Enfermedad Crónica , Oclusión Coronaria/diagnóstico por imagen , Oclusión Coronaria/fisiopatología , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/efectos adversos , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
16.
Pituitary ; 22(2): 146-155, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30847775

RESUMEN

INTRODUCTION: Hypophysial and hypothalamic dysfunction caused by craniopharyngioma is a serious problem despite the progress of surgical approaches and techniques. Perifocal edema induced by craniopharyngioma could be speculated as a potential factor resulting in pre- and post-operative hypophysial and hypothalamic dysfunction, as well as, their anatomical involvement. METHODS: Medical records of 54 patients with craniopharyngioma were retrospectively reviewed. The edema was characterized by a hyperintense area in magnetic resonance imaging, being classified into no edema (group A), only adjacent to the tumor (group B), and extending to the internal capsule or the optic tract (group C). Age, sex, tumor diameter, presence of cyst, hydrocephalus, intracranial pressure (ICP) elevation, visual function impairment, hypopituitarism, diabetes insipidus, memory disturbance, and obesity were investigated. RESULTS: The occurrence rate of edema was found more frequently in adults (73.7%) than in children (25.0%). The peritumoral edema grading system had an excellent correlation with the degree of hypothalamic involvement graded by the Puget's system. Pre-operative ICP elevation was significantly detected in group C when compared with the other groups. In adults patients, group C was significantly associated with the occurrence of hydrocephalus both in pre- and post-operatively. Pre- and post-operative hypothalamic dysfunction, including diabetes insipidus, memory disturbance, and obesity, were highest in group C. CONCLUSION: Hypothalamic dysfunctions greatly influence the quality of daily living following craniopharyngioma surgery. The grading of perifocal edema's extension could be a new index suggesting pre- and post-operative hypothalamic dysfunction caused by craniopharyngioma in addition to their anatomical involvement.


Asunto(s)
Craneofaringioma/diagnóstico por imagen , Adulto , Anciano , Craneofaringioma/patología , Edema/diagnóstico por imagen , Edema/patología , Femenino , Humanos , Hipotálamo/diagnóstico por imagen , Hipotálamo/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
17.
J Phys Chem A ; 122(49): 9579-9584, 2018 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-30430832

RESUMEN

We developed a system to deposit H2O molecules onto ultrathin silicon nitride substrates in situ using time-resolved transmission electron diffraction apparatus and performed ultrafast time-resolved electron diffraction measurements in the noncrystalline (amorphous) H2O under near-ultraviolet photoexcitation. The observed dynamics directly represent O-H bond dissociation via multiphoton absorption and charge transfer, which trigger ionization and intermolecular disorder in the amorphous H2O. Our results illustrate the intriguing nature of light-matter and matter-matter interactions in H2O molecules.

18.
Endocr J ; 65(10): 1061-1067, 2018 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-30078825

RESUMEN

A 43-year-old woman with an 8-year history of diabetes, hypertension, and dyslipidemia presented with amenorrhea and convulsion. Her MRI scan revealed a 3.5-cm T2-hyperintense pituitary macroadenoma with suprasellar extension to the frontal lobe and bilateral cavernous sinus invasion. Her serum levels of GH and insulin-like growth factor-I (IGF-I) were elevated to 9.08 ng/mL (normal range: <2.1 ng/mL) and 1,000 ng/mL (normal range: 90-233 ng/mL, SD score +10.6), respectively. Bromocriptine insufficiently suppressed her GH levels, while octreotide paradoxically increased her GH levels. Together with her characteristic features, she was diagnosed with acromegaly caused by an invasive GH-producing pituitary macroadenoma. As performing a one-stage operation would have been extremely difficult, she was first treated with pasireotide long-acting release (40 mg monthly) for 5 months followed by a successful transsphenoidal surgery. One month after the first injection, biochemical control was achieved (IGF-I, 220 ng/mL; GH, 1.26 ng/mL), and tumor shrinkage of approximately 50% was observed. The resected tumor was histologically diagnosed as a sparsely granulated somatotroph adenoma, with higher expression of somatostatin receptor subtype 5 (SSTR5) than that of SSTR2A. The germline aryl hydrocarbon receptor interacting protein (AIP) mutation was negative, and several tumor cells were weakly immunoreactive for AIP. Despite the presence of a residual tumor postoperatively, biochemical control was achieved 6 months after the final injection of pasireotide. In conclusion, this case suggests that pasireotide may be an option for preoperative first-line therapy in invasive and octreotide-resistant sparsely granulated somatotroph adenomas.


Asunto(s)
Acromegalia/tratamiento farmacológico , Adenoma Hipofisario Secretor de Hormona del Crecimiento/cirugía , Neoplasias Hipofisarias/cirugía , Somatostatina/análogos & derivados , Acromegalia/etiología , Acromegalia/cirugía , Adulto , Terapia Combinada , Femenino , Adenoma Hipofisario Secretor de Hormona del Crecimiento/complicaciones , Humanos , Neoplasias Hipofisarias/complicaciones , Cuidados Preoperatorios , Somatostatina/uso terapéutico , Resultado del Tratamiento
19.
J Neuroradiol ; 45(6): 362-367, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29524498

RESUMEN

BACKGROUND AND PURPOSE: Hemodynamic impairments are considered risk factors of cerebral hyperperfusion after carotid artery stenting (CAS); measurement by Single-photon emission computed tomography (SPECT) using a subjective region of interest (ROI) method lacks consistency and reproducibility. MATERIALS AND METHODS: The present study compared objective perfusion analysis (stereotactic extraction estimation [SEE] method) with the ROI method for preoperative SPECT to predict the hyperperfusion phenomenon (HPP) after CAS. Preoperative resting asymmetry index (cerebral blood flow [CBF] ratio from the affected to unaffected hemisphere) and cerebrovascular reactivity (CVR) to acetazolamide were measured by N-isopropyl-p-[123I]-iodoamphetamine SPECT using the SEE and ROI method in 84 patients. CBF was also measured the day after CAS. Perfusion data with the highest area under the curve (AUC) by receiver-operating characteristic (ROC) analysis was considered a perfusion risk factor of HPP. Multivariate analyses for clinical characteristics and perfusion risk factors were performed to determine predictors of HPP. RESULTS: The HPP was observed in 10 patients (11.9%). Female sex, contralateral stenosis, and degree of stenosis were significantly associated with HPP development on univariate analysis, and symptomatic stenosis was not found to be a significant factor. On SPECT analysis, CVR in the MCA area by SEE method had the highest AUC (0.981). Multivariate analysis showed that CVR in the MCA area was a significant predictor of HPP (P=0.041). To predict hyperperfusion, the ROC curve of the CVR showed a cutoff value of -0.60%, sensitivity of 94.6%, and specificity of 100% (P<0.001). CONCLUSIONS: Objective SEE method had better a predictive capability than ROI method to identify risk of hyperperfusion after CAS.


Asunto(s)
Acetazolamida/administración & dosificación , Estenosis Carotídea/cirugía , Trastornos Cerebrovasculares/diagnóstico por imagen , Stents/efectos adversos , Encéfalo/irrigación sanguínea , Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Trastornos Cerebrovasculares/etiología , Femenino , Humanos , Masculino , Complicaciones Posoperatorias , Factores de Riesgo , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión de Fotón Único
20.
J Am Chem Soc ; 139(44): 15792-15800, 2017 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-29037042

RESUMEN

Aromaticity of photoexcited molecules is an important concept in organic chemistry. Its theory, Baird's rule for triplet aromaticity since 1972 gives the rationale of photoinduced conformational changes and photochemical reactivities of cyclic π-conjugated systems. However, it is still challenging to monitor the dynamic structural change induced by the excited-state aromaticity, particularly in condensed materials. Here we report direct structural observation of a molecular motion and a subsequent packing deformation accompanied by the excited-state aromaticity. Photoactive liquid crystal (LC) molecules featuring a π-expanded cyclooctatetraene core unit are orientationally ordered but loosely packed in a columnar LC phase, and therefore a photoinduced conformational planarization by the excited-state aromaticity has been successfully observed by time-resolved electron diffractometry and vibrational spectroscopy. The structural change took place in the vicinity of excited molecules, producing a twisted stacking structure. A nanoscale torque driven by the excited-state aromaticity can be used as the working mechanism of new photoresponsive materials.

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