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1.
Nature ; 619(7968): 52-56, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37407680

RESUMEN

The orbital Hall effect1 refers to the generation of electron orbital angular momentum flow transverse to an external electric field. Contrary to the common belief that the orbital angular momentum is quenched in solids, theoretical studies2,3 predict that the orbital Hall effect can be strong and is a fundamental origin of the spin Hall effect4-7 in many transition metals. Despite the growing circumstantial evidence8-11, its direct detection remains elusive. Here we report the magneto-optical observation of the orbital Hall effect in the light metal titanium (Ti). The Kerr rotation by the orbital magnetic moment accumulated at Ti surfaces owing to the orbital Hall current is measured, and the result agrees with theoretical calculations semi-quantitatively and is supported by the orbital torque12 measurement in Ti-based magnetic heterostructures. This result confirms the orbital Hall effect and indicates that the orbital angular momentum is an important dynamic degree of freedom in solids. Moreover, this calls for renewed studies of the orbital effect on other degrees of freedom such as spin2,3,13,14, valley15,16, phonon17-19 and magnon20,21 dynamics.

2.
Korean J Gastroenterol ; 82(1): 35-39, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37489081

RESUMEN

The results of the IMbrave150 study have led to widespread use of the combination therapy of atezolizumab and bevacizumab as a first-line treatment for unresectable or metastatic hepatocellular carcinoma (HCC). Compared to traditional cytotoxic chemotherapy agents, immune checkpoint inhibitors show a spectrum of side effects ranging from mild side effects such as skin rash to potentially severe systemic effects such as myocarditis. We present a case of transverse myelitis diagnosed during the treatment of HCC with atezolizumab and bevacizumab combination therapy.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Mielitis Transversa , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/tratamiento farmacológico , Bevacizumab/efectos adversos , Mielitis Transversa/diagnóstico , Mielitis Transversa/etiología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/tratamiento farmacológico
3.
Front Vet Sci ; 9: 935476, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35903139

RESUMEN

Transmissible spongiform encephalopathies (TSEs) also known as prion diseases, are fatal neurodegenerative diseases. Prion diseases are caused by abnormal prion protein (PrPSc) derived from normal prion protein (PrPC), which is encoded by the prion protein gene (PRNP). Prion diseases have been reported in several mammals. Notably, chickens, one species of bird, have not been reported to develop prion diseases and showed resistance to bovine spongiform encephalopathy (BSE) infection. However, genetic polymorphisms of the PRNP gene and protein structure of the prion protein (PrP) related to vulnerability to prion diseases have not been investigated in pheasants, another species of bird. We performed amplicon sequencing of the pheasant PRNP gene to identify genetic polymorphisms in 148 pheasants. We analyzed the genotype, allele and haplotype frequencies of the pheasant PRNP polymorphisms. In addition, we evaluated the effect of genetic polymorphisms of the pheasant PRNP gene on pheasant PrP by the AMYCO, PROVEAN, PolyPhen-2 and PANTHER softwares. Furthermore, we compared the amino acid sequences of tandem repeat domains and secondary and tertiary structures of prion proteins (PrPs) among several animals. Finally, we investigated the impact of non-synonymous single nucleotide polymorphisms (SNPs) on hydrogen bonds and tertiary structures of pheasant PrP by Swiss PDB viewer software. We identified 34 novel genetic polymorphisms of the pheasant PRNP gene including 8 non-synonymous SNPs and 6 insertion/deletion polymorphisms. Among the non-synonymous SNPs, the L23F, G33C and R177Q SNPs showed that they could have a deleterious effect on pheasant PrP. In addition, the R177Q SNP was predicted to show an increase in amyloid propensity and a reduction in hydrogen bonds of pheasant PrP. Among the insertion/deletion polymorphisms, c.163_180delAACCCGGGGTATCCCCAC showed that it could have a detrimental effect on pheasant PrP. Furthermore, secondary and tertiary structures of pheasant PrP were predicted to have structures similar to those of chicken PrP. To the best of our knowledge, this is the first study on genetic polymorphisms of the pheasant PRNP gene.

4.
Phys Rev Lett ; 123(3): 036806, 2019 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-31386425

RESUMEN

The Berry curvature dipole is a physical quantity that is expected to allow various quantum geometrical phenomena in a range of solid-state systems. Monolayer transition metal dichalcogenides provide an exceptional platform to modulate and investigate the Berry curvature dipole through strain. Here, we theoretically demonstrate and experimentally verify for monolayer MoS_{2} the generation of valley orbital magnetization as a response to an in-plane electric field due to the Berry curvature dipole. The measured valley orbital magnetization shows excellent agreement with the calculated Berry curvature dipole, which can be controlled by the magnitude and direction of strain. Our results show that the Berry curvature dipole acts as an effective magnetic field in current-carrying systems, providing a novel route to generate magnetization.

5.
J Pharmacopuncture ; 22(4): 225-230, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31970019

RESUMEN

OBJECTIVES: This study was to discuss the research trend of dementia treatment using cannabis for the purpose of providing the basis of cannabis use for medical purposes in the future. METHODS: This study searched publications, which were registered to databases or published by Aug 22, 2019, and targeted the full-text or abstracts of these publications. We selected the final nine studies met all selection criteria. RESULTS: These results implied that the CBD components of cannabis might be useful to treat and prevent AD because CBD components could suppress the main causal factors of AD. Moreover, it was suggested that using CBD and THC together could be more useful than using CBD or THC alone. CONCLUSION: We hope that there will be a solid foundation to use cannabis for medical use by continuously evaluating the possibility of using cannabis for clinical purposes as a dementia treatment substance and cannabis can be used as a positive tool.

6.
Korean J Anesthesiol ; 66(3): 230-6, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24729846

RESUMEN

BACKGROUND: G protein-coupled receptor, family C, group 5 (GPRC5B), a retinoic acid-inducible orphan G-protein-coupled receptor (GPCR), is a member of the group C metabotropic glutamate receptor family proteins presumably related in non-canonical Wnt signaling. In this study, we investigated altered GPRC5B expression in the dorsal horn of the spinal cord after spinal nerve injury and its involvement in the development of neuropathic pain. METHODS: After induction of anesthesia by intraperitoneal injection of pentobarbital (35 mg /kg), the left L5 spinal nerve at the level of 2 mm distal to the L5 DRG was tightly ligated with silk and cut just distal to the ligature. Seven days after nerve injury, animals were perfused with 4% paraformaldehyde, and the spinal cords were extracted and post-fixed at 4℃ overnight. To identify the expression of GPRC5B and analyze the involvement of GPRC5B in neuropathic pain, immunofluorescence was performed using several markers for neurons and glial cells in spinal cord tissue. RESULTS: After L5 spinal nerve ligation (SNL), the expression of GPRC5B was decreased in the ipsilateral part, as compared to the contralateral part, of the spinal dorsal horn. SNL induced the downregulation of GPRC5B in NeuN-positive neurons in the spinal dorsal horn. However, CNPase-positive oligodendrocytes, OX42-positive microglia, and GFAP-positive astrocytes were not immunolabeled with GPRC5B antibody in the spinal dorsal horn. CONCLUSIONS: These results imply that L5 SNL-induced GPRC5B downregulation may affect microglial activation in the spinal dorsal horn and be involved in neuropathic pain.

7.
Chonnam Med J ; 50(3): 86-90, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25568843

RESUMEN

MicroRNA (miRNA) pathways have been implicated in stem cell regulation. This study investigated the molecular effects of propofol on adipocyte stem cells (ASCs) by analyzing RNA expression arrays. Human ASCs were isolated by use of a liposuction procedure. ASCs were treated with saline, 50 µM propofol, or 100 µM propofol in culture media for 3 hours. After the isolation of total RNA, the expression of 76 miRNAs was evaluated with peptide nucleic acid-miRNA array analysis through denaturation and hybridization processes. Treatment with 50 µM propofol resulted in significant down-regulation of expression of 18 miRNAs and upregulation of expression of 25 miRNAs; 100 µM propofol resulted in significant downregulation of expression of 14 miRNAs and upregulation of expression of 29 miRNAs. The lowest expression was seen for miR-204, which was 0.07-fold with 50 µM propofol and 0.18-fold with 100 µM propofol. The highest expression was seen for miR-208b, which was 11.23-fold with 50 µM propofol and 11.20-fold with 100 µM propofol. Expression patterns of miRNAs were not significantly different between 50 µM and 100 µM propofol treatment. The results of this study suggest that propofol is involved in altering the miRNA expression level in human ASCs. Additional research is necessary to establish the functional effect of miRNA alteration by propofol.

8.
Korean J Anesthesiol ; 67(6): 425-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25558345

RESUMEN

An 81-year-old male patient was scheduled for a laparoscopic cholecystectomy due to acute cholecystitis. About 50 minutes into the operation, the arterial blood pressure suddenly decreased and ventricular fibrillation appeared on the electrocardiography. The patient received cardiopulmonary resuscitation and recovered a normal vital sign. We suspected a carbon dioxide embolism as the middle hepatic vein had been injured during the surgery. We performed a transesophageal echocardiography and were able to confirm the presence of multiple gas bubbles in all of the cardiac chambers. After the operation, the patient presented a stable hemodynamic state, but showed weaknesses in the left arm and leg. There were no acute lesions except for a chronic cerebral cortical atrophy and chronic microvascular encephalopathy on the postoperative brain-computed tomography, 3D angiography and magnetic resonance image. Fortunately, three days after the operation, the patient's hemiparesis had entirely subsided and he was discharged without any neurologic sequelae.

9.
World J Gastroenterol ; 19(3): 411-4, 2013 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-23372366

RESUMEN

Endoscopic epinephrine injection is relatively easy, quick and inexpensive. Furthermore, it has a low rate of complications, and it is widely used for the management of nonvariceal upper gastrointestinal bleeding. There have been several case reports of gastric ischemia after endoscopic injection therapy. Inadvertent intra-arterial injection may result in either spasm or thrombosis, leading to subsequent tissue ischemia or necrosis, although the stomach has a rich vascular supply and the vascular reserve of the intramural anastomosis. In addition to endoscopic injection therapy, smoking, hypertension and atherosclerosis are risk factors of gastric ischemia. We report a case of gastric ischemia after submucosal epinephrine injection in a 51-year-old woman with hypertension and liver cirrhosis.


Asunto(s)
Epinefrina/efectos adversos , Isquemia/diagnóstico , Isquemia/etiología , Cirrosis Hepática/complicaciones , Estómago/irrigación sanguínea , Vasoconstrictores/efectos adversos , Biopsia , Comorbilidad , Endoscopía del Sistema Digestivo/efectos adversos , Epinefrina/administración & dosificación , Epinefrina/uso terapéutico , Femenino , Hemorragia Gastrointestinal/prevención & control , Humanos , Hipertensión/epidemiología , Inyecciones , Cirrosis Hepática/epidemiología , Persona de Mediana Edad , Necrosis/patología , Estómago/patología , Resultado del Tratamiento , Vasoconstrictores/administración & dosificación , Vasoconstrictores/uso terapéutico
10.
Korean J Anesthesiol ; 62(6): 536-42, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22778889

RESUMEN

BACKGROUND: The aim of this study was to investigate whether a small dose of midazolam and lessening the propofol dosage could prevent cardiovascular change at tracheal intubation for induction in aged patients. METHODS: Eighty patients over 65 years (ASA physical status 1, 2) scheduled for elective surgery received general anesthesia with remifentanil and propofol or midazolam. Patients in group P (n = 40) were induced with 0.9% NaCl 0.03 ml/kg, propofol 1. 2 mg/kg and remifentanil. Patients in group MP (n = 40) were induced with midazolam 0.03 mg/kg, propofol 0.8 mg/kg and remifentanil. The time taken to reach loss of consciousness (LOC) and the value of bispectral index score (BIS) at LOC were recorded. After LOC, 0.8 mg/kg of rocuronium was given and tracheal intubation was performed. The mean blood pressure (MBP) and heart rate (HR) were recorded before induction as the base value, before intubation, immediately post-intubation and 3 minutes after intubation. RESULTS: Compared with the base values, MBP at before intubation and 3 minutes after intubation was significantly decreased in group P and group MP (P < 0.05). Compared with group P, the decrease of MBP was significantly less at before intubation, immediately after intubation and 3 minutes after intubation in group MP (P < 0.05). The time taken to reach LOC was significantly decreased in group MP compared with that in group P (P < 0.05). There were no significant differences of HR at any time between the two groups. CONCLUSIONS: Co-induction with midazolam and propofol could prevent a marked BP decrease at tracheal intubation for induction in aged patients.

11.
Korean J Anesthesiol ; 63(6): 491-7, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23277808

RESUMEN

BACKGROUND: The intubation difficulty scale (IDS) has been used as a validated difficulty score to define difficult intubation (DI). The purpose of this study is to identify airway assessment factors and total airway score (TAS) for predicting DI defined by the IDS. METHODS: There were 305 ASA physical status 1-2 patients, aged 19-70 years, who underwent elective surgery with endotracheal intubation. During the pre-anesthetic visit, we evaluated patients by 7 preoperative airway assessment factors, including the following: Mallampati classification, thyromental distance, head & neck movement, body mass index (BMI), buck teeth, inter-incisor gap, and upper lip bite test (ULBT). After endotracheal intubation, patients were divided into 2 groups based on their IDS score estimated with 7 variables: normal (IDS < 5) and DI (IDS ≥ 5) groups. The incidence of TAS (> 6) and high score of each airway assessment factor was compared in two groups: odds ratio, confidence interval (CI) of 95%, with a significant P value ≤ 0.05. RESULTS: The odds ratio of TAS (> 6), ULBT (class III), head & neck movement (< 90°), inter-incisor gap (< 4 cm), BMI (≥ 25 kg/m(2)) and Mallampati classification (≥ class III) were respectively 13.57 (95% CI = 2.99-61.54, P < 0.05), 12.48 (95% CI = 2.50-62.21, P < 0.05), 3.11 (95% CI = 0.87-11.13), 2.32 (95% CI = 0.75-7.19), 2.22 (95% CI = 0.81-6.06), and 1.22 (95% CI = 0.38-3.89). CONCLUSIONS: We suggest that TAS (> 6) and ULBT (class III) are the most useful factors predicting DI.

12.
Korean J Anesthesiol ; 59(3): 167-72, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20877700

RESUMEN

BACKGROUND: The purpose of this study was to investigate a dosage of remifentanil for attenuating cardiovascular changes during anesthetic induction in pediatric anesthesia. METHODS: We examined the effect of remifentanil on the cardiovascular responses to intubation in 90 children ASA 1 patients, aged 4-15 years, randomly allocated to receive 1.0 ug/kg remifentanil as a bolus (R 1), or 1.5 ug/kg remifentanil (R 1.5), or 2.0 ug/kg remifentanil (R 2). Before induction, IV midazolam 0.05 mg/kg was given for sedation. After glycoppylorate 5 ug/kg, thiopental 4.0 mg/kg was injected within 10 seconds and followed by remifentanil. Following check the unconsciousness, patients were received rocuronium 0.6 mg/kg and tracheal intubation were performed 90s later, and anesthesia was maintained with 2% sevoflurane in air/oxygen. Systolic arterial pressure (SAP), mean arterial pressure (MAP) and heart rate (HR) were measured at before induction of anesthesia (B), before, just after and at 1, and 3 minutes after tracheal intubation. RESULTS: SAP and HR were increased than B values in the three groups just after intubation (P < 0.05). The percentage increases of SAP and HR were 30% and 30% of B values, respectively, in R 1; 19% and 24% in R 1.5; 10% and 22% in R 2. There were significant differences between R 2 group and other two groups in SAP and HR (P < 0.05). CONCLUSIONS: In pediatric anesthesia, a bolus injection of 2 ug/kg remifentanil (R 2) was a dosage to attenuate the cardiovascular responses after intubation in pediatric patients.

13.
Korean J Anesthesiol ; 58(6): 508-13, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20589173

RESUMEN

BACKGROUND: It was well-known that smoking affects the cardiovascular system, and remifentanil can suppress the sympathetic stimulations induced by tracheal intubation. The purpose of this study was to investigate whether there was any difference in the hemodynamic changes induced by tracheal intubation with using remifentanil between smokers and nonsmokers. METHODS: EIGHTY PATIENTS WERE ENROLLED: male smokers (MS), male nonsmokers (MN), female smokers (FS) and female nonsmokers (FN). Anesthesia was induced with diluted remifentanil (20 microg/ml) at a rate of 10 microg/kg/hr using an infusion pump, and 2 min later, midazolam 0.05 mg/kg and propofol 0.8 mg/kg were injected for achieving unconsciousness. Rocuronium 1 mg/kg was used for muscle relaxation, and tracheal intubation was performed 2 min after rocuronium injection. After tracheal intubation, the remifentanil was decreased to 2 microg/kg/hr. The mean arterial pressure (MAP) and heart rate (HR) were checked before induction, on unconsciousness, just before intubation, just after intubation and 1, 2 and 3 minutes after intubation, and these values were compared between the groups. RESULTS: In men, the MAP and HR just after intubation and at 1, 2 and 3 minutes after intubation in Group MS were significantly higher than those of Group MN (P < 0.05). For the women, the HR in both groups (the FS and FN groups) were increased just after intubation and 1, 2 and 3 minutes after intubation compared with that at the baseline, respectively, but there was no difference between the two groups. CONCLUSIONS: There was a difference of the hemodynamic changes induced by tracheal intubation with using remifentanil between the male smokers and nonsmokers, but not in women.

14.
Korean J Anesthesiol ; 58(4): 383-90, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20508797

RESUMEN

BACKGROUND: Survivin is thought to contribute to stem cell maintenance partly by a hypomethylation mechanism. This study attempted to elucidate the signal transduction pathway of adipocyte-derived stem cells (ASCs) by using a demethylating agent, 5-aza-2'-deoxycytidine (ADC), to analyze the survivin, MEK/ERK, c-Myc and p53 gene expression. METHODS: Demethylation in the ASCs was induced by 1 microM ADC treatment. RT-PCR for survivin mRNA was preformed, before and 24, 48 and 72 hours (hr) after ADC treatment. Western blotting analysis was performed for p53, survivin, unphosphorylated and phosphorylated (p)-MEK, and p-ERK. Immunohistochemistry for ERK and survivin was done to evaluate the localization of the proteins. RESULTS: ADC inhibited the population growth of the ASCs and it increased the number of apoptotic cells 24, 48, and 72 hr after treatment. ADC treatment slightly decreased the expression of survivin mRNA after 48 hr and its level was restored after 72 hr of treatment. Otherwise, the level of survivin protein gradually increased up to 48 hr and it was decreased at 72 hr. The levels of p-MEK and p53 were increased time-dependently. c-Myc and p-ERK were elevated after ADC treatment and their highest levels were seen 48 hr after treatment. The ADC treatment increased the nuclear expression of ERK and survivin in the ASCs. CONCLUSIONS: The overexpression of p-MEK/ERK, p53, and c-Myc increased the survivin protein expression of the demethylated ASCs. These results suggest that demethylation could alter the expression of survivin, and p53, c-Myc and the MAPK (MEK/ERK) pathway might play a role in survivin's regulation in ASCs.

15.
Korean J Anesthesiol ; 57(1): 20-25, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30625825

RESUMEN

BACKGROUND: Hypertensive patients are more prone to exhibit an exaggerated hemodynamic responses to laryngoscopy and tracheal intubation. We compared the effects of remifentanil and lidocaine on the cardiovascular responses during intubation in hypertensive patients. METHODS: Fifty adult hypertensive patients (>140/90 mmHg) were divided into 2 groups (remifentanil group; 1.0 microgram/kg, n = 25, lidocaine group; 1.5 mg/kg, n = 25). After 3 minutes'oxygenation, anesthesia was induced using 0.2 mg glycopyrrolate, 1.5 mg/kg propofol, and 1 of experimental drugs (30 seconds) bolus administration. Tracheal intubation was facilitated 90 seconds after administration of rocuronium; anesthesia was maintained with 2% sevoflurane and air in oxygen. Arterial blood pressure and heart rate were measured at the following times: resting state (baseline), after oxygenation; before intubation; just after intubation; and at 1, 3, and 5 minutes after intubation. RESULTS: There was significant attenuation of mean systolic and diastolic arterial blood pressures, after intubation of the remifentanil group compared to the lidocaine group at just after intubation and at 1 minute after intubation (P < .05). The difference in heart rate was not significant between both groups. CONCLUSIONS: Bolus administration of remifentanil was found to be superior to lidocaine in the attenuation of the blood pressure during intubation in hypertensive patients.

16.
Neurosci Lett ; 411(1): 56-60, 2007 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-17095154

RESUMEN

Transient recovery (TR) of evoked synaptic potentials and ATP depletion during the late stage of hypoxic hypoglycemic insults were investigated in rat hippocampal slices. TR was observed not only in the late stage of insult, but also during recovery. The concentration of ATP corresponded to the appearance (27% of control) and disappearance (15% of control) of TR. Paired pulse studies showed the presynaptic nature of the release of inhibition of synaptic transmission during TR. Both N- and P/Q-type voltage-dependent calcium channels were involved in the appearance of TR. This evidence suggests that underlying mechanisms of TR appearance during hypoxic hypoglycemic insult might be related to ATP depletion and release of A1 adenosine receptor mediated inhibition of presynaptic voltage-dependent calcium channels.


Asunto(s)
Adenosina Trifosfato/metabolismo , Hipocampo/fisiopatología , Hipoglucemia/patología , Potenciales Postsinápticos Inhibidores/fisiología , Terminales Presinápticos/fisiología , Animales , Bloqueadores de los Canales de Calcio/farmacología , Interacciones Farmacológicas , Estimulación Eléctrica/métodos , Técnicas In Vitro , Potenciales Postsinápticos Inhibidores/efectos de los fármacos , Potenciales Postsinápticos Inhibidores/efectos de la radiación , Masculino , Terminales Presinápticos/efectos de los fármacos , Antagonistas de Receptores Purinérgicos P1 , Ratas , Ratas Sprague-Dawley , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/fisiología , Xantinas/farmacología , omega-Conotoxina GVIA/farmacología
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