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1.
Mar Drugs ; 18(2)2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-32013063

RESUMO

Skin is an important barrier to protect the body from environmental stress. However, exposure to ultraviolet radiation (UV) and various environmental oxidative stresses can cause skin inflammation. Cyclooxygenase-2 (COX-2) is an inducible enzyme that mediates the formation of prostaglandin E2 (PGE2) against internal and external inflammatory stimulations. Therefore, the inhibition of COX-2 is an important approach to maintain skin health and prevent skin inflammation and carcinogenesis. Topsentin, a bis(indolyl)imidazole alkaloid isolated from the marine sponge Spongosorites genitrix, has been reported to exhibit anti-tumor and anti-microbial activities. However, the effect of topsentin on skin inflammation and its underlying molecular mechanism has not been elucidated. In the present study, we identified the photoprotective effects of topsentin on UVB irradiated human epidermal keratinocyte HaCaT cells. Topsentin suppresses COX-2 expression and its upstream signaling pathways, AP-1 and MAPK. Furthermore, topsentin inhibits miR-4485, a new biomarker selected from a microarray, and its target gene tumor necrosis factor alpha induced protein 2 (TNF-α IP2). The photoprotective effect of topsentin was also confirmed in a reconstructed human skin model. These findings suggest that topsentin may serve as a potential candidate for cosmetic formulations with skin inflammatory-mediated disorder.

2.
J Nat Prod ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31967465

RESUMO

Isocadiolides A-H (1-8) and cadiolide N (9), new polybrominated aromatic compounds, were isolated from a Korean Synoicum sp. ascidian. On the basis of the results of extensive spectroscopic analyses, these compounds possessed tris-bromohydroxyphenyl moieties as a common structural motif, while their cores varied [cyclopentenedione (1-5), dihydrofuran (6 and 7), pyranone (8), and furanone (9)], reflecting different extents of rearrangement and oxidation. Several of these compounds exhibited weak antibacterial activities and moderate abilities to inhibit the microbial enzymes sortase A and isocitrate lyase.

3.
World Neurosurg ; 133: e640-e645, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31568907

RESUMO

BACKGROUND: Concomitant chemoradiation (CCRT) after surgical resection has been established as standard care for patients with newly diagnosed glioblastoma (GBM). However, the optimal time interval from surgery to starting CCRT (IST) remains controversial. METHODS: The electronic medical records of 160 patients with newly diagnosed GBM treated at our institution between 2009 and 2016 were examined retrospectively. The eligibility criteria were newly diagnosed GBM, pathology confirmed by craniotomy or stereotactic biopsy, and CCRT performed in our institution. Patients who received CCRT within 28 days after surgery were defined as the early group, and those who received CCRT at >28 days after surgery were defined as the delayed group. RESULTS: We included 138 patients who met our eligibility criteria. The median IST was 26 days (range, 10-55 days). In a Kaplan-Meier analysis, overall survival (OS) did not differ between groups (15.5 month for the early group vs. 14.5 months for the delayed group; P = 0.707). In the gross total resection (GTR) subgroup, OS did not differ significantly (20.0 months for the early vs. 21.0 months for the delayed group; P = 0.854). In the non-GTR subgroup, however, the early group had better OS than the delayed group (11.0 months vs. 5.0 months; P = 0.029). CONCLUSIONS: Performing CCRT within versus after 28 days after surgery did not result in a statistically significant difference in OS. However, a subgroup analysis showed that delayed CCRT may be associated with worse OS in the non-GTR group.


Assuntos
Neoplasias Encefálicas/terapia , Quimiorradioterapia/métodos , Glioblastoma/terapia , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Quimiorradioterapia/mortalidade , Intervalo Livre de Doença , Feminino , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/mortalidade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
4.
J Clin Neurosci ; 71: 21-25, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31843432

RESUMO

Several studies have been conducted to determine the relationship between post-treatment total lymphocyte count (TLC) and overall survival (OS) in patients with malignant tumors including glioblastomas (GBMs). In this retrospective study, whether patients with newly diagnosed GBM experience significant lymphopenia after concomitant chemoradiation (CCRT) was evaluated, and whether TLC after this treatment is associated with OS in the treated population was examined. Using electronic medical records, all patients newly diagnosed with GBM between 2008 and 2016 at Seoul St. Mary's Hospital were retrospectively examined. The eligible criteria included the following: 1) craniotomy with surgical resection or biopsy, 2) completion of CCRT, 3) accessible baseline and/or follow-up complete blood count (CBC). Median TLC significantly decreased after completion of CCRT, compared to TLC at baseline (1742 versus 1319 cells/mm3, P-value < 0.001). Patients with TLC < 1200 cells/mm3 at 4 weeks after the completion of CCRT showed shorter survival than those with TLC ≥ 1200 cells/mm3 with median OS of 14.5 versus 21.0 months (P-value = 0.017). Also, in multivariate analysis for OS, TLC < 1200 cells/mm3 at 4 weeks after the completion of CCRT (HR 1.97, 95% CI 1.61 - 2.25, P-value = 0.004) were significantly associated with shorter survival. The results from the present study indicate that treatment-related total lymphocyte counts after CCRT is associated with worse survival in patients with newly diagnosed GBM.

5.
Brain Tumor Res Treat ; 7(2): 63-73, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31686436

RESUMO

BACKGROUND: There was no practical guideline for the management of patients with central nervous system tumor in Korea in the past. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, developed the guideline for glioblastoma successfully and published it in Brain Tumor Research and Treatment, the official journal of KSNO, in April 2019. Recently, the KSNO guideline for World Health Organization (WHO) grade III cerebral glioma in adults has been established. METHODS: The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified by searches in PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL databases using specific and sensitive keywords as well as combinations of keywords. Scope of the disease was confined to cerebral anaplastic astrocytoma and oligodendroglioma in adults. RESULTS: Whenever radiological feature suggests high grade glioma, maximal safe resection if feasible is globally recommended. After molecular and histological examinations, patients with anaplastic astrocytoma, isocitrate dehydrogenase (IDH)-mutant should be primary treated by standard brain radiotherapy and adjuvant temozolomide chemotherapy whereas those with anaplastic astrocytoma, NOS, and anaplastic astrocytoma, IDH-wildtype should be treated following the protocol for glioblastomas. In terms of anaplastic oligodendroglioma, IDH-mutant and 1p19q-codeletion, and anaplastic oligodendroglioma, NOS should be primary treated by standard brain radiotherapy and neoadjuvant or adjuvant PCV (procarbazine, lomustine, and vincristine) combination chemotherapy. CONCLUSION: The KSNO's guideline recommends that WHO grade III cerebral glioma of adults should be treated by maximal safe resection if feasible, followed by radiotherapy and/or chemotherapy according to molecular and histological features of tumors.

6.
Brain Tumor Res Treat ; 7(2): 74-84, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31686437

RESUMO

BACKGROUND: There was no practical guideline for the management of patients with central nervous system tumor in Korea for many years. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, has developed the guideline for glioblastoma. Subsequently, the KSNO guideline for World Health Organization (WHO) grade II cerebral glioma in adults is established. METHODS: The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified by searching PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL databases using specific and sensitive keywords as well as combinations of keywords regarding diffuse astrocytoma and oligodendroglioma of brain in adults. RESULTS: Whenever radiological feature suggests lower grade glioma, the maximal safe resection if feasible is recommended globally. After molecular and histological examinations, patients with diffuse astrocytoma, isocitrate dehydrogenase (IDH)-wildtype without molecular feature of glioblastoma should be primarily treated by standard brain radiotherapy and adjuvant temozolomide chemotherapy (Level III) while those with molecular feature of glioblastoma should be treated following the protocol for glioblastomas. In terms of patients with diffuse astrocytoma, IDH-mutant and oligodendroglioma (IDH-mutant and 1p19q codeletion), standard brain radiotherapy and adjuvant PCV (procarbazine+lomustine+vincristine) combination chemotherapy should be considered primarily for the high-risk group while observation with regular follow up should be considered for the low-risk group. CONCLUSION: The KSNO's guideline recommends that WHO grade II gliomas should be treated by maximal safe resection, if feasible, followed by radiotherapy and/or chemotherapy according to molecular and histological features of tumors and clinical characteristics of patients.

7.
Brain Tumor Res Treat ; 7(1): 1-9, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31062525

RESUMO

BACKGROUND: There has been no practical guidelines for the management of patients with central nervous system (CNS) tumors in Korea for many years. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, started to prepare guidelines for CNS tumors from February 2018. METHODS: The Working Group was composed of 35 multidisciplinary medical experts in Korea. References were identified through searches of PubMed, MEDLINE, EMBASE, and Cochrane CENTRAL using specific and sensitive keywords as well as combinations of keywords. RESULTS: First, the maximal safe resection if feasible is recommended. After the diagnosis of a glioblastoma with neurosurgical intervention, patients aged ≤70 years with good performance should be treated by concurrent chemoradiotherapy with temozolomide followed by adjuvant temozolomide chemotherapy (Stupp's protocol) or standard brain radiotherapy alone. However, those with poor performance should be treated by hypofractionated brain radiotherapy (preferred)±concurrent or adjuvant temozolomide, temozolomide alone (Level III), or supportive treatment. Alternatively, patients aged >70 years with good performance should be treated by hypofractionated brain radiotherapy+concurrent and adjuvant temozolomide or Stupp's protocol or hypofractionated brain radiotherapy alone, while those with poor performance should be treated by hypofractionated brain radiotherapy alone or temozolomide chemotherapy if the patient has methylated MGMT gene promoter (Level III), or supportive treatment. CONCLUSION: The KSNO's guideline recommends that glioblastomas should be treated by maximal safe resection, if feasible, followed by radiotherapy and/or chemotherapy according to the individual comprehensive condition of the patient.

8.
Int J Clin Oncol ; 24(6): 666-676, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30788672

RESUMO

BACKGROUND: Brain metastasis is a rare event in patients with hepatocellular carcinoma (HCC). This retrospective study aimed to identify the prognostic factors and determine the outcomes of patients with brain metastases from HCC. METHODS: About 86 patients with brain metastases (0.6%) from HCC were identified from two institutions; of them, 32 underwent tumor-removing surgery or stereotactic radiosurgery (SRS) with or without adjuvant whole brain radiotherapy (WBRT) (group 1), 30 had WBRT alone (group 2), and 24 received conservative treatment (group 3). Estimates for overall survival (OS) after brain metastases were determined, and clinical prognostic factors were identified. RESULTS: The median OS after development of brain metastases was 50 days. About 75 (87.2%) patients had lung metastases at the time of brain metastasis diagnosis. Group 1 showed better OS, followed by group 2 and group 3, sequentially (p < 0.001). Univariate analyses showed that treatment with curative intent (surgery or SRS), Child-Pugh class A, alpha-fetoprotein level < 400 ng/ml, and recursive partitioning analysis classification I or II were associated with improved survival (p < 0.001, 0.002, 0.029, and 0.012, respectively). Multivariate analysis showed that treatment with curative intent and Child-Pugh class A was associated with improved OS (p < 0.001 and 0.009, respectively). CONCLUSION: Although the overall prognosis of patients with brain metastases from HCC is extremely poor, patients actively treated with surgery or radiosurgery have prolonged survival, suggesting that interventions to control intracranial disease are important in these patients.


Assuntos
Neoplasias Encefálicas/mortalidade , Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/mortalidade , Radiocirurgia/mortalidade , Adulto , Idoso , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
9.
Clin Exp Otorhinolaryngol ; 12(1): 12-17, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30326700

RESUMO

Endoscopic sinus and skull base surgeries are minimally invasive surgical techniques that reduce postoperative symptoms and complications and enhance patients' quality of life. However, to ensure excellent surgical outcomes after such interventions, intimate familiarity with important landmarks and high-level endoscope manipulation skills are essential. Cadaver training is one possible option, but cadavers are expensive, scarce, and nonreusable and cadaver work requires specialized equipment and staff. In addition, it is difficult to mimic specific diseases using cadavers. Virtual reality simulators can create a computerized environment in which the patient's anatomy is reproduced and interaction with endoscopic handling and realistic haptic feedback is possible. Moreover, they can be used to present scenarios that improve trainees' skills and confidence. Therefore, virtual simulator training can be implemented at all levels of surgical education. This review introduces the current literature on virtual reality training for endoscopic sinus and skull base surgeons, and discusses the direction of future developments.

10.
J Neurosurg ; : 1-8, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30579277

RESUMO

OBJECTIVE: Microvascular decompression (MVD) is widely considered the treatment of choice for hemifacial spasm (HFS), but not all patients immediately benefit from it. Numerous electrophysiological tests have been employed to monitor the integrity of the facial nerve prior to, during, and after MVD treatment. The authors sought to verify if facial motor evoked potential (FMEP) with paired transcranial magnetic stimulation (pTMS) can be utilized as a tool to predict prognosis following MVD for HFS. METHODS: FMEP using pTMS was performed preoperatively and postoperatively for 527 HFS patients who underwent an MVD treatment. Various interstimuli intervals (ISIs), which included 2, 10, 20, 25, 30, 75, and 100 msec, were applied for each paired stimulation and pTMS(%) was obtained. A graph of pTMS(%) versus each ISI was drawn for every patient and its pattern was analyzed in accordance with patients' clinical outcomes. RESULTS: With ISIs of 75 and 100 msec, pTMS(%) was physiologically further inhibited, whereas it was relatively facilitated under ISIs of 20, 25, and 30 msec; loss of this specific pattern, that is, further inhibition-relative facilitation, indicated impaired integrity of the facial nerve. Those patients who immediately benefited from an MVD and experienced no relapse tended to show proper restoration of this further inhibition-relative facilitation pattern (p = 0.01). Greater resemblance between the physiological pattern of pTMS(%) and postoperative pTMS(%) was correlated to better outcome (p = 0.019). CONCLUSIONS: A simple linear graph of pTMS(%) versus each ISI may be a helpful tool to predict prognosis for HFS following an MVD.

11.
J Neurol Surg B Skull Base ; 79(6): 569-573, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30456026

RESUMO

Objective This article describes the role played by endoscopic endonasal transsphenoidal approach (EETSA) to the sphenoidal process of the septal cartilage of a deviated nasal septum. Design Case series with chart review. Setting Tertiary referral center. Participants Between 2009 and 2016, 177 patients with skull base tumors who underwent EETSA were included. Main Outcome Measures In 8 cases, the conventional two nostrils-four hands technique was employed (group A). In 16 cases, we placed a right-side conventional nasoseptal flap and a left-side modified nasoseptal rescue flap (group B), and in 153 cases, bilateral modified nasoseptal rescue flaps (group C). The number of septoplasty-required cases and the change of nasal cavity area differences reflecting septal deviation were measured. Results Septoplasty during EETSA was performed in two cases: one from group B and one from group C. There was no significant difference in the ratio of septoplasty-required cases among the three groups ( p = 0.127). Between pre- and postoperative nasal cavity, the cross-sectional area difference at the anterior end of the middle turbinate level significantly decreased ( p = 0.045). Also, the angle of deviation at the level of ostiomeatal unit significantly decreased after EETSA ( p < 0.001). Conclusion Separation of a deviated complex surrounding the sphenoidal process of the septal cartilage is the key to relieving a deviated nasal septum. EETSA combined with the two nostrils-four hands technique allows posterior septectomy (including removal of this deviated complex) to be performed. Thus, EETSA may commence without preceding septoplasty even in cases with severe nasal septum deviations.

12.
Healthc Inform Res ; 24(4): 327-334, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30443421

RESUMO

Objectives: The objective of this study was to investigate the relationship between the level of Electronic Medical Record (EMR) system adoption and healthcare information technology (IT) infrastructure. Methods: Both survey and various healthcare administrative datasets in Korea were used. The survey was conducted during the period from June 13 to September 25, 2017. The chief information officers of hospitals were respondents. Among them, 257 general hospitals and 273 small hospitals were analyzed. A logistic regression analysis was conducted using the SAS program. Results: The odds of having full EMR systems in general hospitals statistically significantly increased as the number of IT department staff members increased (odds ratio [OR] = 1.058, confidence interval [CI], 1.003-1.115; p = 0.038). The odds of having full EMR systems was significantly higher for small hospitals that had an IT department than those of small hospitals with no IT department (OR = 1.325; CI, 1.150-1.525; p < 0.001). Full EMR system adoption had a positive relationship with IT infrastructure in both general hospitals and small hospitals, which was statistically significant in small hospitals. The odds of having full EMR systems for small hospitals increased as IT infrastructure increased after controlling the covariates (OR = 1.527; CI, 1.317-4.135; p = 0.004). Conclusions: This study verified that full EMR adoption was closely associated with IT infrastructure, such as organizational structure, human resources, and various IT subsystems. This finding suggests that political support related to these areas is indeed necessary for the fast dispersion of EMR systems into the healthcare industry.

13.
Opt Express ; 26(16): 20975-20989, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30119404

RESUMO

This research demonstrates that a surface plasmon resonance (SPR) imaging technique can effectively measure full-field nanoscale thickness of a liquid water film filled in the receding contact-induced nano-channel. To the authors' knowledge this has not been demonstrated previously. Experimental calibration has been conducted by measuring surface plasmon resonance reflectance depending on the piezometer-controlled water nano-film thickness and comparing the experimental results with the theoretical calculations to show very good agreement. The measured full-field thickness profiles significantly visualize the three-dimensional nano-channel formation filled with liquid water film. It shows that the sensitivity and the resolution in thickness measurement are estimated as 1.21 pixel gray level/nm and 2.5 nm, respectively. The experimentally observed resolution is around 10 nm given the uncertainty in the demonstrated full-field mapping of thickness. From this research, it is demonstrated that SPR imaging successfully measures the thickness of ultrathin liquid film especially below 85 nm in full-field under normal conditions and can effectively characterize the three-dimensional nano-channel formation during the receding contact process.

14.
World Neurosurg ; 115: e178-e184, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29649644

RESUMO

OBJECTIVE: We sought to examine the utility of an endoscopic transseptal approach and creation of a bilateral nasoseptal flap using a 2-nostrils/4-hands technique in patients with challenging skull-base tumors. METHODS: The medical records of patients operated on via an endoscopic transseptal approach between 2009 and 2017 were retrospectively reviewed. Two patients with ossifying fibroma, 2 with orbital hemangioma, 2 with trigeminal nerve schwannoma, and 1 patient each with juvenile angiofibroma, meningioma, and myxofibrosarcoma were included in the study. The surgical technique and endoscopic anatomy are presented. RESULTS: The mean age of the 4 male and 5 female patients was 39.9 ± 14.8 years. By using this technique, all 7 tumors were resected with minimal nasal morbidity after a mean follow-up of 15.2 ± 9.4 months. CONCLUSIONS: The endoscopic transseptal approach, by creation of a bilateral nasoseptal flap using a 2-nostrils/4-hands technique, improves surgical visualization and increases instrument maneuverability. Surgical access to challenging skull-base tumors is therefore afforded. The procedure also reduces nasal morbidity by preserving the lacrimal apparatus and anterior maxilla structures and avoiding septal perforation and traumatic nose traction.


Assuntos
Septo Nasal/diagnóstico por imagem , Septo Nasal/cirurgia , Neuroendoscopia/métodos , Neoplasias da Base do Crânio/diagnóstico por imagem , Neoplasias da Base do Crânio/cirurgia , Retalhos Cirúrgicos , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
J Craniofac Surg ; 29(3): e319-e322, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29485571

RESUMO

BACKGROUND: To investigate the effect of rhinosinusitis in patients who undergo surgery via the endoscopic endonasal transsphenoidal approach (EETSA). METHODS: The authors retrospectively reviewed the medical records of patients who underwent surgery via the EETSA between February 2009 and November 2016. In total, 505 patients were included in the study. Preoperative paranasal sinus computed tomography, sellar magnetic resonance imaging, and nasal endoscopy were performed for all the patients. RESULTS: Fifteen patients without sphenoid sinusitis underwent surgery with the concomitant transsphenoidal approach and functional endoscopic sinus surgery, and showed no central nervous system (CNS) complication. During surgery via the EETSA, the presence of rhinosinusitis did not significantly affect the incidence of postoperative CNS infection (P = 0.051), except for sphenoid sinusitis (P = 0.003). Conversely, the incidence of postoperative CNS infection was not related significantly to the Lund-Mackay score or tumor size. The risk of CNS infection was 12.151-fold higher in patients with sphenoid sinusitis (95% confidence interval, 3.153-46.827; P ≤ 0.001). CONCLUSION: Surgery via the EETSA and functional endoscopic sinus surgery can be safely performed together in most patients with rhinosinusitis. However, sphenoid sinus infection appears to be a predisposing factor for postoperative CNS infection. Therefore, a separate surgical procedure for sphenoid lesions should be considered in these patients before the use of the EETSA.


Assuntos
Infecções do Sistema Nervoso Central/etiologia , Endoscopia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Sinusite/complicações , Neoplasias da Base do Crânio/cirurgia , Seio Esfenoidal/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Endoscopia/métodos , Feminino , Humanos , Incidência , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Nariz/cirurgia , Seios Paranasais/diagnóstico por imagem , Estudos Retrospectivos , Rinite/complicações , Fatores de Risco , Base do Crânio/cirurgia , Osso Esfenoide/cirurgia , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
16.
J Nanosci Nanotechnol ; 18(3): 1847-1850, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448670

RESUMO

The surface activated bonding (SAB) method generally has the advantage of high bonding strength, low contact resistance, and high microstructural stability at room temperature. In this study, Ti-Al laminates were produced by surface activated bonding with aluminum and titanium foils. Heat treatment was conducted at the temperature range from 200 to 550 °C in vacuum. The bonding strength Ti-Al laminates was measured by a peel test, and the interfacial characteristics were investigated microstructural observation. The results showed that the bonding strength was the highest with heat treatment at 400 °C, microstructure observation revealed that the bonding strength of the Ti-Al laminate was influenced by the interfacial characteristics.

17.
Bioelectromagnetics ; 39(1): 68-76, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29171038

RESUMO

We investigated whether exposure to the 915 MHz radiofrequency identification (RFID) signal affected circulating blood cells in rats. Sprague-Dawley rats were exposed to RFID at a whole-body specific absorption rate of 2 W/kg for 8 h per day, 5 days per week, for 2 weeks. Complete blood counts were performed after RFID exposure, and the CD4+ /CD8+ ratio was determined by flow cytometry. The number of red blood cells (RBCs) and the values of hemoglobin, hematocrit, and RBC indices were increased in the RFID-exposed group compared with those in the cage-control and sham-exposed groups (P < 0.05). However, the RBCs and platelet numbers were within normal physiologic response ranges. The number of white blood cells, including lymphocytes, was decreased in RFID-exposed rats. However, there was no statistically significant difference between the sham-exposed and RFID-exposed groups in terms of T-cell counts or CD4+ /CD8+ ratio (P > 0.05). Although the number of circulating blood cells was significantly altered by RFID exposure at a whole-body specific absorption rate of 2 W/kg for 2 weeks, these changes do not necessarily indicate that RFID exposure is harmful, as they were within the normal physiological response range. Bioelectromagnetics. 39:68-76, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
Células Sanguíneas/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Dispositivo de Identificação por Radiofrequência , Animais , Células Sanguíneas/citologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos da radiação , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/efeitos da radiação , Contagem de Células , Eritrócitos/citologia , Eritrócitos/efeitos da radiação , Masculino , Ratos , Ratos Sprague-Dawley , Irradiação Corporal Total/efeitos adversos
18.
J Craniofac Surg ; 29(3): 543-546, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29283943

RESUMO

BACKGROUND AND OBJECTIVE: The aim of this study is to investigate the relationships between tumor size, nasal symptoms including olfactory function, and posoperative atrophic mucosal changes after the endoscopic endonasal transsphenoidal approach (EETSA). METHODS: This was a retrospective review of the medical records of 112 patients who underwent the 2 nostrils/4 hands EETSA with bilateral modified nasoseptal rescue flaps between February 2009 and January 2016. Pre- and postoperative paranasal sinus computed tomography, nasal cavity endoscopic images, the Connecticut Chemosensory Clinical Research Center (CCCRC) test, Cross-Cultural Smell Identification Test (CCSIT), the Nasal Obstruction Symptoms Evaluation, and the Sino-Nasal Outcome Test-20 were conducted. Nasal mucosal changes as determined by endoscopy were divided into 4 groups: normal to normal, Group A; atrophy to atrophy, Group B; normal to atrophy, Group C; and atrophy to more atrophy, Group D. The Mimics program was used to calculate nasal cavity volume changes after surgery. RESULTS: There were significant differences between pre- and postoperative olfactory function as reflected by the CCCRC (P < 0.001) and CCSIT (P < 0.001) scores. There was also a correlation between tumor size and olfactory function scores such as the CCCRC (P = 0.012) or CCSIT (P = 0.015). Moreover, nasal mucosal atrophic changes were related to tumor size and olfactory function tests. CONCLUSION: The tumor size was related to olfactory function and atrophic mucosal changes. Therefore, patients with large tumors should be informed that, after the EETSA, their olfaction may be altered and that nasal symptoms related to mucosal atrophy could occur.


Assuntos
Endoscopia/métodos , Nariz/cirurgia , Transtornos do Olfato/etiologia , Complicações Pós-Operatórias/etiologia , Neoplasias da Base do Crânio/cirurgia , Base do Crânio/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Cavidade Nasal/anatomia & histologia , Mucosa Nasal/patologia , Obstrução Nasal/etiologia , Seios Paranasais/diagnóstico por imagem , Estudos Retrospectivos , Retalhos Cirúrgicos , Tomografia Computadorizada por Raios X , Adulto Jovem
19.
J Korean Neurosurg Soc ; 60(6): 738-748, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29142635

RESUMO

Objective: We present our experience of microvascular decompression (MVD) for glossopharyngeal neuralgia (GPN) and evaluate the postoperative outcomes in accordance with four different operative techniques during MVD. Methods: In total, 30 patients with intractable primary typical GPN who underwent MVD without rhizotomy and were followed for more than 2 years were included in the analysis. Each MVD was performed using one of four different surgical techniques: interposition of Teflon pieces, transposition of offending vessels using Teflon pieces, transposition of offending vessels using a fibrin-glue-coated Teflon sling, and removal of offending veins. Results: The posterior inferior cerebellar artery was responsible for neurovascular compression in 27 of 30 (90%) patients, either by itself or in combination with other vessels. The location of compression on the glossopharyngeal nerve varied; the root entry zone (REZ) only (63.3%) was most common, followed by both the REZ and distal portion (26.7%) and the distal portion alone (10.0%). In terms of detailed surgical techniques during MVD, the offending vessels were transposed in 24 (80%) patients, either using additional insulation, offered by Teflon pieces (15 patients), or using a fibrin glue-coated Teflon sling (9 patients). Simple insertion of Teflon pieces and removal of a small vein were also performed in five and one patient, respectively. During the 2 years following MVD, 29 of 30 (96.7%) patients were asymptomatic or experienced only occasional pain that did not require medication. Temporary hemodynamic instability occurred in two patients during MVD, and seven patients experienced transient postoperative complications. Neither persistent morbidity nor mortality was reported. Conclusion: This study demonstrates that MVD without rhizotomy is a safe and effective treatment option for GPN.

20.
Sci Rep ; 7(1): 3246, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28607350

RESUMO

We are reporting a 3D printable composite paste having strong thixotropic rheology. The composite has been designed and investigated with highly conductive silver nanowires. The optimized electrical percolation threshold from both simulation and experiment is shown from 0.7 vol. % of silver nanowires which is significantly lower than other composites using conductive nano-materials. Reliable conductivity of 1.19 × 102 S/cm has been achieved from the demonstrated 3D printable composite with 1.9 vol. % loading of silver nanowires. Utilizing the high conductivity of the printable composites, 3D printing of designed battery electrode pastes is demonstrated. Rheology study shows superior printability of the electrode pastes aided by the cellulose's strong thixotropic rheology. The designed anode, electrolyte, and cathode pastes are sequentially printed to form a three-layered lithium battery for the demonstration of a charging profile. This study opens opportunities of 3D printable conductive materials to create printed electronics with the next generation additive manufacturing process.

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