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1.
RSC Adv ; 13(38): 26375-26379, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37671339

RESUMO

Caged compounds protected with photolabile protecting groups (PPGs) are useful for controlling various biological events with high spatiotemporal resolution. Most of the commonly used PPGs are controlled by ultraviolet light irradiation, but it is desirable to have PPGs controlled by visible light irradiation in order to minimize tissue damage. Here, we describe a boron-dipyrromethene (BODIPY)-picolinium conjugate (BPc group) that functions as a blue-light-controllable PPG. ESR experiments indicate that the photolysis mechanism is based on intramolecular photoinduced electron transfer. We illustrate the applicability of the BPc group to biologically active compounds by employing it firstly to photocontrol release of histamine, and secondly to photocontrol release of a soluble guanylyl cyclase (sGC) activator, GSK2181236A, which induces photovasodilation. The BPc group is expected to be a useful PPG for controlling various biological events with blue light irradiation.

2.
Beilstein J Nanotechnol ; 14: 175-189, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36761682

RESUMO

The recently proposed high-low Kelvin probe force microscopy (KPFM) enables evaluation of the effects of semiconductor interface states with high spatial resolution using high and low AC bias frequencies compared with the cutoff frequency of the carrier transfer between the interface and bulk states. Information on the energy spectrum of the interface state density is important for actual semiconductor device evaluation, and there is a need to develop a method for obtaining such physical quantities. Here, we propose high-low Kelvin probe force spectroscopy (high-low KPFS), an electrostatic force spectroscopy method using high- and low-frequency AC bias voltages to measure the interface state density inside semiconductors. We derive an analytical expression for the electrostatic forces between a tip and a semiconductor sample in the accumulation, depletion, and inversion regions, taking into account the charge transfer between the bulk and interface states in semiconductors. We show that the analysis of electrostatic forces in the depletion region at high- and low-frequency AC bias voltages provides information about the interface state density in the semiconductor bandgap. As a preliminary experiment, high-low KPFS measurements were performed on ion-implanted silicon surfaces to confirm the dependence of the electrostatic force on the frequency of the AC bias voltage and obtain the interface state density.

3.
World J Clin Cases ; 10(27): 9821-9827, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36186208

RESUMO

BACKGROUND: Corrected transposition of the great arteries (cTGA) is a cardiac malformation in which the ventricular and arterial-ventricular positions in the heart are doubly reversed. In general, this defect puts a load on the systemic circulation and causes heart failure, resulting in a poor prognosis. This article reports a case of cTGA detected in a patient with post-caesarean pregnancy who had undergone elective caesarean section and was experiencing an episode of acute heart failure. CASE SUMMARY: This was the case of a 36-year-old gravida 3 para 1 woman. No problems were noted in the puerperal course following the previous pregnancy. The current pregnancy was also uneventful. An elective caesarean section was performed and the patient was discharged from the hospital 7 d after the operation. On postoperative day 18, the patient became aware of breathing difficulty and presented at a nearby clinic, where she was referred to our institution after bilateral pleural effusions were detected. She was then diagnosed with acute heart failure after noting the presence of a prominent pedal oedema and SpO2 91% (supine position and room air); the patient was promptly hospitalised for close examination and treatment. Although chest computed tomography revealed the presence of cTGA, no other cardiac malformations were observed. Owing to improvements in both the pedal oedema and pleural effusions, the patient was discharged on day 9. CONCLUSION: Close examination should be performed on the premise of congenital cardiac malformation when heart failure symptoms are noted during perinatal control.

4.
Taiwan J Obstet Gynecol ; 61(2): 353-355, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35361400

RESUMO

OBJECTIVE: X-linked hydrocephalus (XLH), the most common genetic hydrocephalus, is caused by mutation of the L1 cell adhesion molecule (L1CAM). A fetus/neonate with this disorder frequently shows an adducted thumb, which has been employed as a helpful finding in the prenatal diagnosis of XLH. MATERIALS AND METHODS: We describe a male fetus with hydrocephalus without an adducted thumb: the pregnancy was terminated at 21 weeks' gestation on the parents' request. Direct sequencing of the umbilical cord revealed L1CAM mutation, which confirmed the diagnosis of XLH. RESULTS: Our literature review demonstrated that while an adducted thumb was observed in almost all fetuses with this disorder after 24 weeks' gestation, it was noted in only 57% (8/14) of fetuses/neonates at less than 24 weeks: it was absent in 43%. CONCLUSION: Even if an adducted thumb is not observed, XLH should not be ruled out, especially in early gestation.


Assuntos
Hidrocefalia , Polegar , Feminino , Humanos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/genética , Recém-Nascido , Masculino , Linhagem , Gravidez , Segundo Trimestre da Gravidez , Diagnóstico Pré-Natal
5.
Microscopy (Oxf) ; 71(2): 98-103, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35018450

RESUMO

Comparative measurements between frequency modulation Kelvin probe force microscopy (FM-KPFM) using low frequency bias voltage and heterodyne FM-KPFM using high frequency bias voltage were performed on the surface potential measurement. A silicon substrate patterned with p- and n-type impurities was used as a quantitative sample. The multi-pass scanning method in the measurements of FM-KPFM and heterodyne FM-KPFM was used to eliminate the effect of the tip-sample distance dependence. The measured surface potentials become lower in the order of the p-type region, n-type region and n+-type region by both FM-KPFM and heterodyne FM-KPFM, which are in good agreement with the order of the work functions of the pn-patterned Si sample. We observed the difference in the surface potentials due to the surface band bending measured by FM-KPFM and heterodyne FM-KPFM. The difference is due to the fact that the charge transfer between the surface and bulk levels may or may not respond to AC bias voltage.

6.
CEN Case Rep ; 10(3): 414-421, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33595829

RESUMO

BACKGROUND: Neuroblastoma is a well-known embryonal cancer; however, adult-onset neuroblastomas are rare. The systemic symptoms are related to catecholamine excretion or intraabdominal mass effects. Only two cases of neuroblastoma with nephrotic syndrome have previously been reported. We herein present the first autopsy case of neuroblastoma in an older individual associated with minimal change nephrotic syndrome. CASE PRESENTATION: A 63-year-old man was admitted to our hospital for investigation of general fatigue. His renal function was normal and his urine was negative for protein. A computed tomography scan showed a renal tumor and intraabdominal lymph node swelling. Approximately 4 months after admission, he suddenly developed acute renal failure and severe proteinuria, and hemodialysis was instituted. A computed tomography scan revealed an increase in the size of the renal tumor and lymph nodes. He died 1 month later and an autopsy was performed. The tumor exhibited diffuse proliferation of tumor cells with scant cytoplasm, namely small blue cell tumor with rosette formation. As a result of immunohistochemical study, a neuroblastoma was diagnosed. Despite the patient's severe renal failure, most glomeruli showed no remarkable changes. The tubular epithelium exhibited detachment and vacuolation. Electron microscopic study of the glomeruli showed diffuse effacement of the foot processes. These features indicate a diagnosis of minimal change nephrotic syndrome with acute tubular injury. CONCLUSIONS: Minimal change nephrotic syndrome is the most common renal manifestation associated with lymphoproliferative malignancies. We here present an extremely rare case of adult-onset neuroblastoma with minimal change nephrotic syndrome.


Assuntos
Nefrose Lipoide/diagnóstico , Neuroblastoma/diagnóstico , Idade de Início , Autopsia , Humanos , Masculino , Pessoa de Meia-Idade , Nefrose Lipoide/complicações , Neuroblastoma/complicações
7.
Beilstein J Nanotechnol ; 11: 1750-1756, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33282622

RESUMO

The atomic arrangement of the Si(110)-(16×2) reconstruction was directly observed using noncontact atomic force microscopy (NC-AFM) at 78 K. The pentagonal structure, which is the most important building block of the reconstruction, was concluded to consist of five atoms, while only four or five spots (depending on tip bias) have been reported with scanning tunneling microscopy (STM). Single atoms were determined to exist near step edges between upper and lower terraces, which have not been reported using STM. These findings are key evidence for establishing an atomic model of the Si(110)-(16×2) reconstruction, which indeed has a complex structure.

8.
Sci Rep ; 3: 2167, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23835605

RESUMO

The phase transition of a nematic liquid crystal containing a push-pull azobenzene dye could be induced efficiently during irradiation with visible light. The dynamical disorganizing effect of the push-pull azobenzene dye on the liquid crystalline order through its trans-cis-trans photoisomerizaion cycle under visible light was contributed to the efficient phase transition. Then, the effects of light irradiation on the motion of small objects dispersed in the liquid crystals containing the push-pull azobenzene were explored, and the manipulation and assembly of those objects were successfully achieved in the nematic phase but also in the smectic phase. The combination of the photo-controlled dynamical change in the liquid crystalline order and the intrinsic self-assembly property of a liquid crystal is promising for use in technologies that require not only the organization of small objects but also the photo-driving of nano- and micro-sized mechanical materials.

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