Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros










Base de dados
Tipo de estudo
Intervalo de ano de publicação
1.
Clin Neurol Neurosurg ; 191: 105710, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32036240

RESUMO

OBJECTIVE: Decompression surgery is the standard treatment for lumbar spinal stenosis (LSS); however, despite the good clinical outcomes reported for this procedure, a relatively high dissatisfaction rate has been reported. We hypothesized that the previously used outcome measures do not accurately reflect patient satisfaction (PS). This study aimed to examine which outcome measures reflect PS accurately in patients undergoing decompression for LSS. PATIENTS AND METHODS: Patients with LSS treated with lumbar decompression surgery between January 2014 and March 2016 were enrolled if they had the preoperative and final follow-up questionnaires including the Numeric Rating Scale (NRS), Roland-Morris Disability Questionnaire (RMDQ), Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), and Short Form-8 (SF-8). PS was evaluated using the question, "How satisfied are you with the overall result of your back operation?". There are four possible answers consisting of "very satisfied (4-point)", "somewhat satisfied (3-point)", "somewhat dissatisfied (2-point)", or "very dissatisfied (1-point)". The Spearman correlation coefficient between PS and each questionnaire was calculated. RESULTS: Postoperative JOABPEQ had strong correlation with PS (r > 0.6) whereas NRS, RMDQ and SF-8 had moderate correlation (0.4

2.
Anticancer Res ; 40(1): 373-377, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31892589

RESUMO

AIM: In colorectal cancer surgery, the efficacy of intestinal blood flow evaluation with the indocyanine green (ICG) fluorescence method using the VISERA ELITE2 system was investigated. PATIENTS AND METHODS: Participants in this study comprised 50 patients who underwent elective laparoscopic colorectal cancer surgery at the Department of Surgery, the Jikei Daisan Hospital. With the ICG fluorescence method, whether it was necessary to change the intestinal transection line for anastomosis was evaluated. RESULTS: For three cases of rectal cancer, the oral transection line determined from macroscopic observation was judged to offer insufficient blood flow according to the ICG fluorescence method. The transection line for anastomosis was changed according to fluorescence. None of these cases showed complications. CONCLUSION: The ICG fluorescence method may allow safe anastomosis in colorectal surgery for cancer.


Assuntos
Cirurgia Colorretal , Verde de Indocianina/química , Laparoscopia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Cirurgia Colorretal/efeitos adversos , Feminino , Fluorescência , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia
3.
Asian Spine J ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31679323

RESUMO

Study Design: Retrospective chart audit. Purpose: This study aimed to investigate the gender difference in pre- and postoperative health-related quality of life (HRQOL) in patients who have had decompression surgery for lumbar spinal stenosis (LSS). Overview of Literature: Gender differences may contribute to variations in disease presentations and health outcomes. The influence of gender on pre- and postoperative HRQOL in spinal disorders remains unclear. Methods: We reviewed 125 patients (79 men and 46 women) who had lumbar spinous process splitting laminectomy (LSPSL) for LSS. We assessed the following clinical information: Japanese Orthopedic Association (JOA) score; numerical rating scale (NRS) for low back pain (LBP), leg pain, and leg numbness; Zurich Claudication Questionnaire; JOA Back Pain Evaluation Questionnaire; Roland- Morris Disability Questionnaire (RMDQ); and Short Form 8 (SF-8) as HRQOL. We compared the HRQOLs of men and women pre- and postoperatively. Results: Although the preoperative NRS results for LBP were significantly higher in women (p <0.05), there were no significant differences in clinical outcomes between men and women postoperatively. For HRQOL, the RMDQ scores were significantly worse in women preoperatively (p <0.05), but no significant differences were found postoperatively between men and women. Similarly, the SF-8 mental health score was also significantly lower in women preoperatively (p <0.05), but no significant differences were noted between the two groups postoperatively. Conclusions: LSPSL greatly reduced LBP, leg pain, and leg numbness in both genders. There were limited differences in pain and several HRQOL questionnaire responses between men and women after surgery. We found that women had greater sensitivity to and/or lower tolerance for pain than men, which led to lower HRQOL mental health scores preoperatively.

4.
Spine J ; 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31622677

RESUMO

BACKGROUND CONTEXT: A previous study examined the short-term (2 years) outcomes of a short fusion strategy for Lenke type 5C curves. This strategy had a little less correction rate with no difference in coronal and sagittal balance and SRS-22 scores to those of a conventional strategy and was superior in operative time and intraoperative bleeding. However, its effectiveness in longer follow-up periods was unknown. PURPOSE: To assess midterm surgical outcomes of a short fusion strategy for adolescent idiopathic scoliosis (AIS) with Lenke type 5C curve, involving posterior correction and fusion surgery (PSF) using pedicle-screw constructs. STUDY DESIGN: Retrospective case series. PATIENT SAMPLE: Twenty-nine patients who underwent PSF for AIS with Lenke type 5C curve with a minimum 5-year follow-up. OUTCOME MEASURES: Radiographic parameters and SRS-22. METHODS: We compared radiographic parameters and clinical outcomes between patients with an upper instrumented vertebra (UIV) at the end vertebra (EV) (n=12) and those treated by short fusion (S), with a UIV one level caudal to the EV (n=17). RESULTS: A preoperative mean Cobb angle of 51.9±13.8° was corrected to 11.7±7.7° in the EV group, and an angle of 46.0±6.6° was corrected to 9.3±5.2° in the S group. The correction was maintained in both groups at the final follow-up, and the mean correction loss was 2.8±6.8° in the EV and 6.5±6.5° in the S group (p=.143). The mean correction rate at the final follow-up was not significantly different between the EV (71.4±11.8%) and S (64.9±13.7%) groups (p=.199). A Cobb angle of a thoracic curve was significantly improved immediately after surgery and maintained during the follow-up period in the both groups. Coronal and sagittal balance, thoracic kyphosis, lumbar lordosis, L4 tilt, UIV/LIV tilt, shoulder balance, and SRS-22 had no difference between the two groups. CONCLUSIONS: There was no difference in radiographic parameters and SRS-22 between patients treated with a UIV at the UEV and patients treated using a short fusion strategy, in which the UIV was one level caudal to the UEV. The short fusion strategy can be one of the alternatives in PSF for Lenke type 5C curves, at least in 5-year time frame.

5.
J Clin Neurosci ; 69: 93-96, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31416735

RESUMO

Decompression surgery is the standard treatment in lumbar spinal stenosis (LSS). Recent studies have shown that patient satisfaction following decompression surgery does not correspond well with outcomes measured by conventional patient-reported outcome measurements. Recent study reported that the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) is the most accurate outcome measurement to reflect patient satisfaction. Nevertheless, the JOABPEQ was not studied enough, especially along with the minimally clinically important differences (MCIDs), as JOABPEQ is relatively new questionnaire. The MCID is the minimum score change which patients perceive as beneficial. Thus, knowing the MCID is critical evaluating the efficacy of intervention. The aim of this study was to determine the MCIDs of the JOABPEQ for patients with LSS undergoing decompression surgery. Patients who underwent decompression surgery for LSS were consecutively enrolled if they had a complete set of questionnaires. We determined the MCIDs of each domain in the JOABPEQ using distribution-based and anchor-based methods. The MCIDs were determined to be 20.4 in low back pain, 15.6 in lumbar function, 16.8 in walking ability, 13.4 in social life function, and 9.4 in mental health by the distribution-based method. Using the anchor-based method, the MCIDs were determined to be 28.5, 16.5, 25.0, 21.5, and 14.5, respectively. The MCIDs of the JOABPEQ in LSS were slightly different from 20-point, which was proposed in the JOABPEQ user's manual. Our findings should be considered when evaluating LSS patients undergoing decompression surgery as JOABPEQ is not LSS specific.


Assuntos
Diferença Mínima Clinicamente Importante , Medição da Dor/métodos , Medidas de Resultados Relatados pelo Paciente , Estenose Espinal/cirurgia , Inquéritos e Questionários/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Descompressão Cirúrgica/métodos , Feminino , Humanos , Japão , Laminectomia/métodos , Dor Lombar/cirurgia , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Ortopedia/métodos , Resultado do Tratamento
6.
Clin Neurol Neurosurg ; 185: 105481, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31442743

RESUMO

OBJECTIVE: The influence of preoperative mental health on health-related quality of life (HRQOL) in patients with lumbar spinal stenosis (LSS) remains unclear. This study aims to investigate the influence of preoperative mental health HRQOL after laminectomy in patients with LSS. PATIENTS AND METHODS: We retrospectively reviewed 122 patients who had lumbar spinous process splitting laminectomy (LSPSL) for LSS. We assessed clinical information; Japanese Orthopedic Association (JOA) score; numerical rating scale (NRS) for low back pain, for leg pain, and for leg numbness; Zurich Claudication Questionnaire (ZCQ); JOA Back Pain Evaluation Questionnaire (JOABPEQ); Roland-Morris Disability Questionnaire (RMDQ); and Short Form 8 (SF-8) as patient reported outcomes. Patients were divided into two groups (Group L ≤ 36.2 points and Group NL > 36.2 points) based on the results of the preoperative mental health (MH) score in SF-8 to examine the influence of MH in LSS. We compared the HRQOL between the two groups postoperatively. RESULTS: The JOA score, NRS, and ZCQ score significantly improved after surgery. HRQOL outcomes including JOABPEQ, RMDQ, and SF-8 showed that the LSPSL improved not only the physical but also the mental function in patients with LSS. All HRQOL outcomes in Group L exhibited significantly worse scores preoperatively; however, no significant differences between two groups were found postoperatively. CONCLUSIONS: LSPSL greatly reduced low back pain, leg pain, and leg numbness. LSPSL resulted in a significant improvement based on HRQOL questionnaires even in patients with preoperative depressive mood. Not only the physical status but also the mental health may improve after LSPSL even in patients with LSS with a depressive mood preoperatively.

7.
Anticancer Res ; 39(6): 3009-3013, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31177142

RESUMO

BACKGROUND/AIM: Indocyanine green (ICG) fluorescence technique is known to help visualize blood vessels. The efficacy of real-time fluorescence vessel navigation (FVN) using ICG for ligation of the inferior mesenteric vein (IMV) and left colic artery (LCA) during laparoscopic left colorectal cancer surgery was investigated. PATIENTS AND METHODS: Participants were 59 patients who underwent laparoscopic left colorectal cancer surgery from February 2017 to November 2018, and were divided into groups: i) with FVN (FVN+, n=21) and ii) without FVN (FVN-, n=38). Groups were compared for the time it took to ligate their IMV and LCA. RESULTS: The results are expressed as median values. The time to ligate the IMV and LCA was significantly shorter for FVN+ (230 seconds; range 126-346) than for FVN- (417.5 seconds; range 137-1327) (p<0.001). CONCLUSION: Real-time FVN using ICG shortened the times for IMV and LCA ligation. This was enabled by clear visualization of the direction of the bloodstream flow inside the vessels. This technique simplifies vessel ligation and safer laparoscopic surgery for left colorectal cancer.


Assuntos
Neoplasias Colorretais/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Corantes Fluorescentes/administração & dosagem , Verde de Indocianina/administração & dosagem , Laparoscopia/métodos , Artérias Mesentéricas/cirurgia , Veias Mesentéricas/cirurgia , Imagem Óptica/métodos , Cirurgia Assistida por Computador/métodos , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/patologia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Feminino , Humanos , Laparoscopia/efeitos adversos , Ligadura , Masculino , Artérias Mesentéricas/diagnóstico por imagem , Veias Mesentéricas/diagnóstico por imagem , Pessoa de Meia-Idade , Duração da Cirurgia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Cirurgia Assistida por Computador/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
8.
J Nat Med ; 73(4): 727-734, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31104253

RESUMO

From the methanolic extract of the leaves of Lansium domesticum, three new onoceranoid-type triterpenoids, lansium acids X-XII and a new cycloartane-type triterpene, lansium acid XIII, were isolated. The chemical structures of the isolated new compounds were elucidated on the basis of chemical/physicochemical evidence. For new onoceranoid-type triterpenoids, the absolute configurations were established by comparison of experimental and predicted electronic circular dichroism (ECD) data. The isolated onoceranoid-type triterpenoids showed antimutagenic effects in the Ames assay against 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1).


Assuntos
Antimutagênicos/farmacologia , Meliaceae/química , Extratos Vegetais/química , Triterpenos/química , Estrutura Molecular , Folhas de Planta , Triterpenos/isolamento & purificação
9.
J Neurosurg Spine ; : 1-7, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771778

RESUMO

OBJECTIVEThe importance of global sagittal alignment is well known. Patients with lumbar spinal stenosis (LSS) generally tend to bend forward to relieve their neurological symptoms, i.e., they have a positive sagittal vertical axis (SVA). We hypothesized that the positive SVA associated with LSS is symptom related and should improve after surgery. However, little is known about the changes in sagittal alignment in LSS patients after decompression surgery. In this study the authors aimed to evaluate midterm radiographical changes in sagittal spinopelvic alignment after decompression surgery for LSS and to determine the factors influencing the improvement in sagittal spinopelvic alignment.METHODSThe authors retrospectively reviewed 89 patients who underwent lumbar decompression without fusion between January 2014 and September 2015 with a minimum follow-up of 2 years. Standing whole-spine radiographs at the preoperative stage and at the final follow-up were examined. We analyzed SVA, lumbar lordosis (LL), pelvic tilt (PT), pelvic incidence (PI), thoracolumbar kyphosis (TLK), and thoracic kyphosis (TK).RESULTSLL and TK were significantly increased postoperatively. SVA and PI minus LL (PI-LL) were significantly decreased. There were no significant differences between the preoperative and postoperative PT, PI, SS, or TLK. Twenty-nine patients had preoperative sagittal malalignment with SVA > 50 mm. Thirteen of the 29 patients improved to SVA < 50 mm after decompression surgery. Lower ASA grade, preoperative higher LL, and lower PI-LL were related to patient improvement. A receiver operating characteristic curve for the preoperative PI-LL had an area under the curve value of 0.821, indicating moderate accuracy (p = 0.003). A cutoff value for preoperative PI-LL of 19.2° showed a sensitivity of 93.5% and a specificity of 71.4%.CONCLUSIONSLumbar decompression can lead to a reactive improvement in the lumbar and global sagittal alignment. However, some of the sagittal malalignment in LSS was irreversible. Preoperative PI-LL was a useful predictor to distinguish reversible from irreversible sagittal malalignment.

10.
J Neurosurg Spine ; : 1-6, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30684939

RESUMO

OBJECTIVEPatients with lumbar spinal stenosis (LSS) tend to bend forward to relieve neurological symptoms. They therefore have a positive sagittal vertical axis (SVA). The importance of the SVA value is well known in the field of adult spinal deformity; however, little is known about its impact on LSS. The authors sought to investigate the impact of sagittal spinopelvic alignment on clinical outcome and health-related quality of life (HRQOL) after decompression surgery for LSS.METHODSThe authors retrospectively reviewed 83 patients who underwent lumbar decompression without fusion between January 2014 and September 2015 with a minimum follow-up of 2 years. Standing whole-spine radiographs were examined preoperatively and at final follow-up. Based on the SVA, patients were allocated to a sagittal balance group (group B; SVA < 50 mm) or a sagittal imbalance group (group I; SVA ≥ 50 mm). The authors compared the groups using Japanese Orthopaedic Association (JOA), Zurich Claudication Questionnaire (ZCQ), Roland-Morris Disability Questionnaire (RMDQ), and the 8-item Short Form Health Survey (SF-8) scores.RESULTSPreoperative groups B (group pre-B) and I (group pre-I) included 58 and 25 patients, respectively. Preoperative sagittal malalignment had negative effects on the JOA score recovery rate, postoperative ZCQ physical function domain score, and numeric rating scale (NRS) score of postoperative low-back pain (LBP), but no significant effects were observed for RMDQ and SF-8 domain scores. Postoperatively, groups B (group post-B) and I (group post-I) included 60 and 23 patients, respectively. Group post-I had a significantly worse JOA score recovery rate, postoperative symptom severity domain score in the ZCQ, and NRS score for postoperative LBP. Similarly, the postoperative RMDQ score and the Physical Component Summary score of the SF-8 were significantly worse in group post-I.CONCLUSIONSPositive SVA had significantly negative effects on clinical outcome and HRQOL in LSS patients after lumbar decompression surgery.

11.
J Nat Prod ; 81(10): 2187-2194, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30335380

RESUMO

A methanol extract of the dried leaves of Lansium domesticum showed antimutagenic effects against 3-amino-1,4-dimethyl-5 H-pyrido[4,3- b]indole (Trp-P-1) and 2-amino-1-methyl-6-phenylimidazo[4,5- bI]pyridine (PhIP) using the Ames assay. Nine new onoceranoid-type triterpenoids, lansium acids I-IX (1-9), and nine known compounds (10-16) were isolated from the extract. The structures of the new compounds were elucidated on the basis of chemical and spectroscopic evidence. The absolute stereostructures of the new compounds were determined via their electronic circular dichroism spectra. Several isolated onoceranoid-type triterpeneoids showed antimutagenic effects in an in vitro Ames assay. Moreover, oral intake of a major constituent, lansionic acid (10), showed antimutagenic effects against PhIP in an in vivo micronucleus test.


Assuntos
Antimutagênicos/farmacologia , Meliaceae/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Triterpenos/farmacologia , Animais , Dicroísmo Circular , Humanos , Camundongos , Testes para Micronúcleos , Estrutura Molecular , Testes de Mutagenicidade , Extratos Vegetais/química , Estereoisomerismo , Triterpenos/química
12.
Sci Rep ; 8(1): 11333, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-30054541

RESUMO

To enlarge both horizontal (azimuthal) and vertical (zenithal) viewing zones simultaneously, a convex parabolic mirror is placed after passing through the hologram. Viewers perceive a three-dimensional (3D) object inside the parabolic mirror as a virtual image by capturing the wavefront radially reflected from the parabolic mirror. The optical experiment using the convex parabolic mirror has demonstrated an extremely wide viewing zone with an azimuthal range of 180° and zenithal range of 90°. The viewing zone and the shape of the parabolic surface are analyzed. The hologram is designed considering the parabolic mirror reflection, and its diffraction calculation method based on Fermat's principle is also proposed.

13.
J Orthop Sci ; 21(4): 512-516, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27262920

RESUMO

OBJECTIVE: To determine the relationship between locomotive syndrome (LS) risk tests and knee osteoarthritis (KOA). STUDY DESIGN: Cross-sectional cohort study. METHODS: In 2015, 225 people (male 84, females 141, mean age 67.9, range 30-90) were examined using LS risk tests, including the stand-up test, the two-step test, and the 25-question risk assessment, in Katashina Village in Gunma prefecture. The Japanese orthopaedic association defined LS risk test stage 1, difficulty with standing from a 40-cm-high seat using one-leg in the stand-up test, two-step test <1.3, the 25-question risk assessment ≧7, and defined stage 2, difficulty with standing from a 20-cm-high seat using both legs in the stand-up test, two-step test <1.1, the 25-question risk assessment ≧16. Persons with two or more of the following on the ultrasound (US) assessment were defined as having KOA: peripheral joint space (PJS) < 5 mm during weight-bearing; medial radial displacement (MRD) > 5 mm during weight-bearing; and osteophytes > 2 mm. If the residents had KOA in either knee, they were defined as having KOA. RESULTS: 45 residents had KOA in either knee. Logistic regression analysis adjusted for age, height, weight, gender, and knee pain was performed with stage 0 as reference. On the stand-up test, the odds ratio was 5.484 (95% confidence interval (CI) 1.966-15.297) for stage 1 and 2.067 (95% CI 0.426-10.017) for stage 2. On the two-step test, the odds ratio was 1.497 (95% CI 0.557-4.021) for stage 1 and 0.71 (95% CI 0.210-2.395) for stage 2. On the 25-question risk assessment, the odds ratio was 1.73 (95% CI 0.646-4.631) for stage 1 and 1.5 (95% CI 0.508-4.433) for stage 2. CONCLUSIONS: A stand-up test of stage 1 had a significant relationship with KOA. This might suggest that proper care of KOA is needed to prevent progressive disability.


Assuntos
Locomoção/fisiologia , Limitação da Mobilidade , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Estudos Transversais , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Síndrome
14.
J Rehabil Res Dev ; 51(7): 1095-102, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25436660

RESUMO

Externally powered upper-limb prostheses are difficult to use because of the lack of sensory feedback. Neuroprostheses have recently been developed for people with upper-limb amputation but are complicated, expensive, and still developing. We therefore designed a simple system by combining pseudo-cineplasty with extended physiological proprioception to provide sensory feedback to the body. We penetrated the palmaris longus tendon percutaneously with a metal ring, similar to that used in body piercing, in a nondisabled subject as a pseudo-cineplasty. The tendon and ring were connected to the system, and a sensory feedback experiment was performed. We investigated the ability of the user to determine the size of an object grasped by the prosthetic hand without visual information. The subject could distinguish between large and small objects with 100% accuracy and between small, medium, and large objects with 80% accuracy. In pseudo-cineplasty, control and sensory feedback are natural because the prosthetic hand is controlled by muscle contraction. Tension transmitted from the prosthetic hand is sensed via muscle spindles and skin sensors. This technique allows only partial sensory feedback but appears to offer several advantages over other human-machine interfaces.


Assuntos
Membros Artificiais , Retroalimentação Sensorial , Contração Muscular/fisiologia , Propriocepção/fisiologia , Tendões/fisiologia , Cotos de Amputação/inervação , Cotos de Amputação/cirurgia , Engenharia Biomédica , Antebraço , Humanos , Desenho de Prótese , Tendões/cirurgia
15.
Biosystems ; 109(2): 145-50, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22465151

RESUMO

Peptide bond formation at the peptidyl transferase center on the ribosome is a crucial phenomenon in life systems. In this study, we conceptually propose possible roles of the RNA tetraplex as a scaffold for two aminoacyl minihelices that enable peptide bond formation. The basic rationale of this model is that "parallel" complementary templates composed of only 10-mer nucleotides can position two amino acids in close proximity, which is conceptually and essentially similar to the situation observed in ribosomes. Using supportive experimental data, we discuss the origin and evolution of peptide bond formation in early biological systems.


Assuntos
Biossíntese Peptídica , RNA/química , Dicroísmo Circular , Ensaio de Desvio de Mobilidade Eletroforética , Transferência Ressonante de Energia de Fluorescência
16.
Chemistry ; 17(21): 5908-20, 2011 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-21495097

RESUMO

A versatile reducing agent, diimide, can be generated efficiently by the aerobic oxidation of hydrazine with neutral and cationic synthetic flavin catalysts 1 and 2. This technique provides a convenient and safe method for the aerobic reduction of olefins, which proceeds with 1 equiv of hydrazine under an atmosphere of O(2) or air. The synthetic advantage over the conventional gas-based method has been illustrated through high hydrazine efficiency, easy and safe handling, and characteristic chemoselectivity. Vitamin B(2) derivative 6 acts as a highly practical, robust catalyst for this purpose because of its high availability and recyclability. Association complexes of 1b with dendritic 2,5-bis(acylamino)pyridine 15 exhibit unprecedented catalytic activities, with the reduction of aromatic and hydroxy olefins proceeding significantly faster when a higher-generation dendrimer is used as a host pair for the association catalysts. Contrasting retardation is observed upon similar treatment of non-aromatic or non-hydroxy olefins with the dendrimer catalysts. Control experiments and kinetic studies revealed that these catalytic reactions include two independent, anaerobic and aerobic, processes for the generation of diimide from hydrazine. Positive and negative dendrimer effects on the catalytic reactions have been ascribed to the specific inclusion of hydrazine and olefinic substrates into the enzyme-like reaction cavities of the association complex catalysts.


Assuntos
Alcenos/química , Flavinas/química , Hidrazinas/química , Imidas/química , Piridinas/química , Catálise , Cátions/química , Dendrímeros/química , Hidrogenação , Estrutura Molecular , Oxirredução
17.
Org Lett ; 12(1): 32-5, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19950976

RESUMO

Various olefins can be hydrogenated quantitatively with neutral flavin 2 catalysts in the presence of 1-2 equiv of hydrazine under 1 atm of O(2). Vitamin B(2) derivative 2g acts as a highly efficient and robust catalyst for the present environmentally benign process producing water and nitrogen gas as the only waste products.


Assuntos
Alcenos/química , Flavinas/química , Hidrazinas/química , Oxigênio/química , Catálise , Hidrogenação , Estrutura Molecular , Nitrogênio/química , Água
18.
Yakugaku Zasshi ; 129(11): 1415-22, 2009 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-19881214

RESUMO

Metallothionein (MT) is a cysteine-rich low molecular weight protein and thought to function in the detoxification of heavy metals and reactive oxygen species. We examined the induction of MT synthesis by cilostazol, an antiplatelet drug, in several vascular component cells to find a new pharmacological effect of cilostazol in vascular system. In human coronary artery endothelial cells, cilostazol significantly increased MT-IX and MT-IIA mRNA levels after the treatment for 6 h and endogenous MT-I/II protein levels after the treatment for 24 and 48 h. In addition, cadmium cytotoxicity was prevented by cilostazol in this endothelial cells. Moreover, cilostazol increased MT-IX and MT-IIA mRNA levels in human coronary artery smooth muscle cells, human brain microvascular endothelial cells, human brain microvascular pericytes and human colon carcinoma Caco-2 cells after the treatment for 6 h. Interestingly, cilostazol also increased MT-III mRNA level in brain microvascular endothelial cells more effectively than in other vascular cells. The present results suggest that cilostazol can protect the vascular system from toxic substances such as heavy metals via MT induction in vascular cells.


Assuntos
Células Endoteliais/metabolismo , Metalotioneína/biossíntese , Músculo Liso Vascular/metabolismo , Inibidores da Agregação de Plaquetas/farmacologia , Tetrazóis/farmacologia , Aterosclerose/etiologia , Aterosclerose/prevenção & controle , Cádmio/antagonistas & inibidores , Cádmio/toxicidade , Células Cultivadas , Cilostazol , Humanos , Metalotioneína/fisiologia , Músculo Liso Vascular/citologia , Proteínas do Tecido Nervoso/biossíntese , Estimulação Química
19.
Acta Med Okayama ; 57(4): 179-86, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14627069

RESUMO

The purpose of this study was to compare the MR characteristics of renal cell carcinomas against histologic findings and to assess the correlations among signal intensity, tumor enhancement, and pathologic findings. Fifty-four patients (56 lesions) were examined by MR imaging and then underwent partial or radical nephrectomy. The pathologic diagnosis of all lesions was renal cell carcinoma. All MR examinations were performed as dynamic studies using the same 1.5-T scanner. MR characteristics were compared against pathologic findings after resection, and the correlations among signal intensity, tumor enhancement, and pathologic findings were then assessed. A significant correlation was observed between tumor grade and tumor enhancement, with G3 lesions tending to show little enhancement. Regardless of the histologic classification, G3 tumors were found to contain highly heterotypic cancer cells and very few vessels by histopathologic examination. No significant correlations were noted between the other MR characteristics and pathologic findings. Renal cell carcinomas showing little enhancement tend to be highly malignant lesions based on the pathologic findings. Special consideration is required for these tumors with regard to the selection of surgical intervention and follow-up observation.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Imagem por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/irrigação sanguínea , Feminino , Humanos , Neoplasias Renais/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Prognóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA