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1.
Knee Surg Relat Res ; 36(1): 12, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539272

RESUMO

INTRODUCTION: Patient satisfaction is an important outcome of total knee arthroplasty (TKA). However, we cannot predict how and why patients are satisfied or dissatisfied with TKA. The hypothesis of this study was that patient-reported outcomes (PROs) correlate with in vivo kinematics after TKA. MATERIALS AND METHODS: One hundred knees were analyzed after TKA. The in vivo kinematics of deep knee bending motion were estimated from single-plane fluoroscopy using a two-to-three-dimensional registration technique. Active knee flexion, femoral rotation and rollback were evaluated. The PROs were obtained after surgery using the 2011 Knee Society Scoring System (KSS), and their relationship with in vivo kinematics was determined. RESULTS: The average minimum and maximum flexion were -2.4 ± 7.3° and 113.2 ± 13.6°, respectively. The average femoral rotation was 7.4 ± 3.4°, and the average medial and lateral rollback were 2.4 ± 4.8 mm and 7.2 ± 5.6 mm, respectively. The multiple regression analysis revealed that the maximum flexion angle significantly contributed to symptoms and satisfaction. In addition, lateral rollback was also a significant factor affecting patient satisfaction. Lateral rollback and lateral Anterior-Posterior (AP) position at maximum flexion were correlated with the maximum flexion angle, whereas femoral rotation did not correlate with flexion angles. CONCLUSIONS: Maximum flexion and lateral rollback are important for better patient satisfaction after TKA. To obtain the maximum flexion angle, it was necessary to perform the normal kinematic pattern with a large amount of lateral rollback.

2.
Radiography (Lond) ; 30(1): 408-415, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38176131

RESUMO

INTRODUCTION: This study aimed to compare the vascular enhancement and radiation dose in preoperative transcatheter aortic valve implantation (TAVI) computed tomography (CT) with a reduced contrast medium (CM) using volume scans in 256-multidetector row CT (MDCT) with a standard CM using 64-MDCT. METHODS: This study included 78 patients with preoperative TAVI CT with either 64- or 256-MDCT. The CM was injected at 1.5 mL/kg in the 64-MDCT group and 1.0 mL/kg in the 256-MDCT group. We compared vascular enhancement of the aortic root and access routes, image quality (IQ) scores, and radiation dose in both groups. RESULTS: Despite the reduced CM (by 33 %) in the 256-MDCT group, the mean vascular enhancement of the right and left subclavian arteries was significantly higher than that in the 64-MDCT group [284 and 267 Hounsfield units (HU) vs. 376 and 359 HU; p < 0.05]; however, no significant differences in the mean vascular enhancement in the ascending aorta, abdominal aorta at the celiac level, and bilateral common femoral arteries were observed between the two groups (p > 0.05 for all). The median IQ scores at the aortic root were higher in the 256-MDCT group than in the 64-MDCT group (3 vs. 4; p < 0.05), and those at the femoral access routes were comparable (4 vs. 4; p = 0.33). The mean effective dose was significantly reduced by 30 % in the 256-MDCT group (23.6 vs. 16.3 mSv; p < 0.05). CONCLUSION: In preoperative TAVI CT, volume scans using 256-MDCT provide comparable or better vascular enhancement and IQ with a 30 % reduction in CM and radiation dose than those using 64-MDCT. IMPLICATIONS FOR PRACTICE: Volume scan using 256-MDCT for preoperative TAVI CT may reduce CM and radiation dose in TAVI patients with renal dysfunction.


Assuntos
Estenose da Valva Aórtica , Iodo , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Tomografia Computadorizada Multidetectores , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Doses de Radiação , Aorta Abdominal
3.
AJNR Am J Neuroradiol ; 44(9): 1057-1063, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37536732

RESUMO

BACKGROUND AND PURPOSE: Contrast-induced encephalopathy can result from neurotoxicity of contrast medium in the affected area. The development of intermediate catheters has allowed guidance of catheters to more distal arteries. This study focused on the association between contrast-induced encephalopathy and contrast injection from an intermediate catheter guided into a distal intradural artery during neurointervention for cerebral aneurysms. MATERIALS AND METHODS: We retrospectively reviewed 420 consecutive aneurysms in 396 patients who underwent neurointervention for extracranial aneurysms and unruptured intracranial aneurysms at our institution from February 2012 to January 2023. Patients were divided into a group with contrast-induced encephalopathy and a group without. To identify risk factors for contrast-induced encephalopathy, we compared clinical, anatomic, and procedural factors between groups by multivariate logistic regression analysis and stepwise selection. RESULTS: Among the 396 patients who underwent neurointervention for cerebral aneurysms, 14 (3.5%) developed contrast-induced encephalopathy. Compared with the group without contrast-induced encephalopathy, the group with contrast-induced encephalopathy showed significantly higher rates of patients on hemodialysis, previously treated aneurysms, intradural placement of a catheter for angiography, nonionic contrast medium, and flow-diversion procedures in univariate analyses. Stepwise multivariate logistic regression analysis revealed intradural placement of a catheter for angiography (OR = 40.4; 95% CI, 8.63-189) and previously treated aneurysms (OR = 8.20; 95% CI, 2.26-29.6) as independent predictors of contrast-induced encephalopathy. CONCLUSIONS: Contrast injection from an intradural artery and retreatment of recurrent aneurysms were major risk factors for contrast-induced encephalopathy. Attention should be paid to the location of the intermediate catheter for angiography to avoid developing contrast-induced encephalopathy.


Assuntos
Encefalopatias , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/terapia , Estudos Retrospectivos , Artérias , Encefalopatias/induzido quimicamente , Encefalopatias/diagnóstico por imagem , Catéteres , Resultado do Tratamento , Angiografia Cerebral/métodos
4.
AJNR Am J Neuroradiol ; 42(2): 306-312, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33361373

RESUMO

BACKGROUND AND PURPOSE: Obtaining information on invisible vasculature distal to the occlusion site helps to deploy a stent retriever safely during mechanical thrombectomy for large-vessel occlusion. It is essential to reduce the amount of contrast used for detecting the vessels distal to the occlusion site because acute ischemic stroke patients tend to have chronic kidney disease and patients with severe chronic kidney disease are at an increased risk of contrast-associated acute kidney injury. We assessed whether vessels distal to the occlusion site during acute ischemic stroke with large-vessel occlusion could be visualized on angiographic images using flat panel detector CT acquired following intra-arterial diluted contrast injection, compared with MRA findings. MATERIALS AND METHODS: Between May 2019 and January 2020, we enrolled 28 consecutive patients with large-vessel occlusions of the anterior circulation eligible for mechanical thrombectomy following MR imaging. The patients underwent CBV imaging using flat panel detector CT with an intra-arterial diluted contrast injection instead of intravenous injection. Flat panel detector CT angiographic images reconstructed from the same dataset were evaluated for image quality, collateral status of the MCA territory, and visualization of the vessels distal to the occlusion site. These findings were compared with MRA findings. RESULTS: Twenty-two patients were retrospectively examined. Flat panel detector CT angiographic image quality in 20 patients (91%) was excellent or good. The distal portion of the occluded vessel segment was visualized in 14 patients (70%), while the proximal portion of the segment adjacent to the occluded vessel in 3 (15%) was visualized. No visualization was observed in only 1 patient (5%) with no collateral supply. Flat panel detector CT angiographic images were shown to evaluate vessels distal to the occlusion site more accurately than MRA. CONCLUSIONS: In acute ischemic stroke with large-vessel occlusion, flat panel detector CT angiographic images could successfully visualize vessels distal to the occlusion site with a small amount of contrast material.


Assuntos
Angiografia Cerebral/métodos , Angiografia por Tomografia Computadorizada/métodos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Trombectomia/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Cirurgia Assistida por Computador/métodos
5.
J Neuroradiol ; 48(4): 311-315, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31563590

RESUMO

BACKGROUND AND PURPOSE: Precise vessel measurement plays a major role in size selection of stents used for the treatment of intracranial aneurysms and became even more critical after the introduction of flow diverter stents. We assessed agreement between intracranial vessel diameters of aneurysm patients measured on 2D digital subtraction (2D DSA) and 3D volume rendering digital subtraction angiography (3D DSA) images using an automatic windowing algorithm. MATERIALS AND METHODS: Ten patients with intracranial aneurysms were enrolled and 120 measurement points were selected on both 2D and 3D DSA images acquired by a biplane angiographic system. Automatic windowing was applied to the 3D DSA images. Inter-method agreement of vessel measurements on 2D and 3D DSA images was assessed by Bland Altman plots and intraclass correlation coefficients (ICC). Inter- and intra-rater agreement of measurements on 3D DSA images were assessed by ICCs. RESULTS: The mean differences between measurements on 2D and 3D DSA images were 0.14mm for the ICA, and 0.18mm for the ACA and MCA, which is about the size of one 3D DSA image voxel. For ICA measurements, inter-method, inter-rater and intra-rater agreements were good or excellent (consistency and absolute ICC≥0.95). For ACA and MCA measurements, the inter-method, inter-rater and intra-rater agreements were also good or excellent (consistency ICC=0.94, 0.89 and 0.93, absolute ICC=0.83, 0.84 and 0.85 respectively). CONCLUSIONS: Vessel diameters may be measured on 3D DSA images with sufficient reliability for clinical use when applying an automatic windowing algorithm.


Assuntos
Aneurisma Intracraniano , Algoritmos , Angiografia Digital , Angiografia Cerebral , Humanos , Imageamento Tridimensional , Aneurisma Intracraniano/diagnóstico por imagem , Reprodutibilidade dos Testes
6.
Artigo em Inglês | MEDLINE | ID: mdl-33301406

RESUMO

OBJECTIVE: To clarify whether there are any muscle synergy changes in individuals with knee osteoarthritis, and to determine whether muscle synergy analysis could be applied to other musculoskeletal diseases. METHODS: Subjects in this study included 11 young controls (YC), 10 elderly controls (EC), and 10 knee osteoarthritis patients (KOA). Gait was assessed on a split-belt treadmill at 3 km/h. A non-negative matrix factorization (NNMF) was applied to the electromyogram data matrix to extract muscle synergies. To assess the similarity of each module, we performed the NNMF analysis assuming four modules for all of the participants. Further, we calculated joint angles to compare the kinematic data between the module groups. RESULTS: The number of muscle modules was significantly lower in the EC (2-3) and KOA (2-3) groups than in the YC group (3-4), which reflects the merging of late swing and early stance modules. The EC and KOA groups also showed greater knee flexion angles in the early stance phase. Contrarily, by focusing on the module structure, we found that the merging of early and late stance modules is characteristic in KOA. CONCLUSION: The lower number of modules in the EC and KOA groups was due to the muscle co-contraction with increased knee flexion angle. Contrarily, the merging of early and late stance modules are modular structures specific to KOA and may be biomarkers for detecting KOA. SIGNIFICANCE: Describing the changes in multiple muscle control associated with musculoskeletal degeneration can serve as a fundamental biomarker in joint disease.


Assuntos
Osteoartrite do Joelho , Idoso , Fenômenos Biomecânicos , Marcha , Humanos , Articulação do Joelho , Músculos
7.
AJNR Am J Neuroradiol ; 41(2): 286-292, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32001447

RESUMO

BACKGROUND AND PURPOSE: Delayed leukoencephalopathy is a rare complication that occurs after endovascular coiling of cerebral aneurysms. We aimed to describe a clinical picture of delayed leukoencephalopathy and explore potential associations with procedural characteristics. MATERIALS AND METHODS: We considered endovascular coiling procedures for cerebral aneurysms performed between January 2006 and December 2017 in our institution with follow-up MRIs. We used logistic regression models to estimate the ORs of delayed leukoencephalopathy for each procedural characteristic. RESULTS: We reviewed 1754 endovascular coiling procedures of 1594 aneurysms. Sixteen of 1722 (0.9%) procedures demonstrated delayed leukoencephalopathy on follow-up FLAIR MR imaging examinations after a median period of 71.5 days (interquartile range, 30-101 days) in the form of high-signal changes in the white matter at locations remote from the coil mass. Seven patients had headaches or hemiparesis, and 9 patients were asymptomatic. All imaging-associated changes improved subsequently. We found indications suggesting an association between delayed leukoencephalopathy and the number of microcatheters used per procedure (P = .009), along with indications suggesting that these procedures required larger median volumes of contrast medium (225 versus 175 mL, OR = 5.5, P = .008) as well as a longer median fluoroscopy duration (123.6 versus 99.3 minutes, OR = 3.0, P = .06). Our data did not suggest that delayed leukoencephalopathy was associated with the number of coils (P = .57), microguidewires (P = .35), and guiding systems (P = .57). CONCLUSIONS: Delayed leukoencephalopathy after coiling of cerebral aneurysms may have multiple etiologies such as foreign body emboli, contrast-induced encephalopathy, or hypersensitivity reaction to foreign bodies.


Assuntos
Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/cirurgia , Leucoencefalopatias/etiologia , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Procedimentos Endovasculares/instrumentação , Feminino , Humanos , Incidência , Leucoencefalopatias/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Stents , Resultado do Tratamento
8.
J Clin Pharm Ther ; 41(4): 399-402, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27144370

RESUMO

WHAT IS KNOWN AND OBJECTIVE: The pharmacokinetic-pharmacodynamic parameter that best predicts the efficacy of vancomycin is the ratio of the area under the concentration versus time curve (AUC) to the minimum inhibitory concentration (MIC). A 24-h AUC (AUC24 )/MIC ratio ≥ 400 was recommended in an American consensus review, but vancomycin treatment occasionally fails despite maintenance of AUC24 /MIC ≥ 400. We evaluated the association between clinical efficacy of vancomycin and two novel pharmacokinetic parameters, the 'area under the trough level' (AUTL) and the 'area above the trough level' (AATL), in hospitalized elderly patients with methicillin-resistant Staphylococcus aureus (MRSA) pneumonia. METHODS: The subjects were hospitalized elderly patients who were administered vancomycin for treatment of MRSA pneumonia between 2006 and 2012 at Sasebo Chuo Hospital (Nagasaki, Japan). Pharmacokinetic parameters of vancomycin were estimated for each patient by Bayesian analysis using population pharmacokinetic parameters for Japanese patients. Based on the patient-specific parameters thus obtained, AUC24 values were calculated as the vancomycin dosage divided by vancomycin clearance. AUTL was calculated as the trough serum concentration multiplied by 24 h, whereas AATL was calculated by subtracting AUTL from AUC24 . RESULTS AND DISCUSSION: Logistic regression analysis demonstrated that efficacy of vancomycin was more strongly associated with AUTL than AUC24 . The optimal cut-off value of AUTL was 331 µg∙h/mL, which means that the optimal cut-off value of the trough serum concentration was 13·8 µg/mL. WHAT IS NEW AND CONCLUSION: Efficacy of vancomycin was associated with AUTL, a novel pharmacokinetic parameter. Determining the target AUTL or trough concentration may enhance the efficacy of vancomycin therapy in elderly patients with MRSA pneumonia. Given that nephrotoxicity may increase with a Ctrough in excess of 15 µg/mL, this level should ideally not be exceeded.


Assuntos
Antibacterianos/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Pneumonia Bacteriana/tratamento farmacológico , Vancomicina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Área Sob a Curva , Teorema de Bayes , Infecção Hospitalar/microbiologia , Feminino , Hospitalização , Humanos , Japão , Modelos Logísticos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Pneumonia Bacteriana/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Resultado do Tratamento , Vancomicina/administração & dosagem , Vancomicina/farmacocinética
9.
Eye (Lond) ; 30(5): 746-53, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26915745

RESUMO

PurposeTo determine whether the concentrations of vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein (MCP)-1 in the vitreous changed after vitrectomy in patients with proliferative diabetic retinopathy (PDR).ParticipantsTwenty-one eyes of 21 patients who needed a second surgery for PDR were included. The reasons for the second surgery were tractional retinal detachment (TRD), neovascular glaucoma, persistent vitreous hemorrhage, macular pucker, and secondary intraocular lens (IOL) implant.MethodsWe measured the VEGF and MCP-1 levels using sandwich enzyme-linked immunosorbent assays in vitreous samples collected from patients with PDR before pars plana vitrectomy (without IOL implantation), and from the same patients during the second surgery.ResultsThere was not significant change in mean VEGF concentrations when comparing first (0.81±0.88 ng/ml) and second surgeries (1.09±1.51 ng/ml). The MCP-1 level was significantly elevated at the time of second surgery (2.20±2.21 ng/ml) compared with the first vitrectomy (0.72±0.57 ng/ml). The MCP-1 levels of the second surgery cases with TRD (3.18±2.27 ng/ml) increased significantly compared with those with other complications (1.72±2.10 ng/ml).ConclusionsAt the second vitrectomy, VEGF did not change significantly in the vitreous of the patients examined. The MCP-1 concentration was markedly elevated at the second vitrectomy, implying an association between the prolonged inflammation after vitrectomy and complications, especially TRD.


Assuntos
Quimiocina CCL2/metabolismo , Retinopatia Diabética/metabolismo , Retinopatia Diabética/cirurgia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Vitrectomia , Corpo Vítreo/metabolismo , Adulto , Idoso , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Descolamento Retiniano/metabolismo , Descolamento Retiniano/cirurgia , Acuidade Visual/fisiologia , Hemorragia Vítrea/metabolismo , Hemorragia Vítrea/cirurgia
10.
AJNR Am J Neuroradiol ; 37(2): 317-23, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26359152

RESUMO

BACKGROUND AND PURPOSE: Combination of high-resolution C-arm CT and novel metal artifact reduction software may contribute to the assessment of aneurysms treated with stent-assisted coil embolization. This study aimed to evaluate the efficacy of a novel Metal Artifact Reduction prototype software combined with the currently available high spatial-resolution C-arm CT prototype implementation by using an experimental aneurysm model treated with stent-assisted coil embolization. MATERIALS AND METHODS: Eight experimental aneurysms were created in 6 swine. Coil embolization of each aneurysm was performed by using a stent-assisted technique. High-resolution C-arm CT with intra-arterial contrast injection was performed immediately after the treatment. The obtained images were processed with Metal Artifact Reduction. Five neurointerventional specialists reviewed the image quality before and after Metal Artifact Reduction. Observational and quantitative analyses (via image analysis software) were performed. RESULTS: Every aneurysm was successfully created and treated with stent-assisted coil embolization. Before Metal Artifact Reduction, coil loops protruding through the stent lumen were not visualized due to the prominent metal artifacts produced by the coils. These became visible after Metal Artifact Reduction processing. Contrast filling in the residual aneurysm was also visualized after Metal Artifact Reduction in every aneurysm. Both the observational (P < .0001) and quantitative (P < .001) analyses showed significant reduction of the metal artifacts after application of the Metal Artifact Reduction prototype software. CONCLUSIONS: The combination of high-resolution C-arm CT and Metal Artifact Reduction enables differentiation of the coil mass, stent, and contrast material on the same image by significantly reducing the metal artifacts produced by the platinum coils. This novel image technique may improve the assessment of aneurysms treated with stent-assisted coil embolization.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Software , Tomografia Computadorizada por Raios X/métodos , Animais , Modelos Animais de Doenças , Embolização Terapêutica/instrumentação , Embolização Terapêutica/métodos , Aneurisma Intracraniano/terapia , Stents , Suínos
11.
Horm Metab Res ; 47(11): 826-32, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26305168

RESUMO

Approximately 10% of cases of hypertension in Japan are caused by primary aldosteronism (PA), amounting to about 4 million patients in total. Primary aldosteronism due to unilateral aldosterone hypersecretion is potentially curable by adrenalectomy. The clinical benefits of identifying and treating PA have been reported internationally, but its cost-effectiveness is unclear. We examined whether diagnosing and treating hidden PA in hypertensive population was cost-effective compared with suboptimal treatment. Our hypothetical patient was a 50-year-old man diagnosed with stage I-III hypertension. We established a Markov decision model based on plausible clinical pathways and prognoses of PA. We applied cost-effectiveness analysis comparing a comprehensive diagnostic strategy for PA (measurement of plasma aldosterone/renin ratio, 2 loading tests, imaging, and selective adrenal venous sampling) with a suboptimal strategy to manage hypertension by medication unless the typical signs of PA or other complication were manifest. Outcome measures were expected costs, expected effectiveness, and incremental cost-effectiveness ratio. The robustness of the findings was established by one-way and scenario sensitivity analyses. The comprehensive PA diagnostic strategy increased the expected costs by 64 004 JPY and expected life-years by 0.013 compared with standard treatment. The incremental cost-effectiveness ratio for the diagnosis of PA was 4 923 385 JPY per year. Our findings were sensitive to the outcomes of screening and treatment, and the costs of continuous or periodic medication for hypertension and the treatment of stroke and its complications.


Assuntos
Análise Custo-Benefício , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/terapia , Humanos , Hiperaldosteronismo/economia , Japão , Masculino , Cadeias de Markov , Pessoa de Meia-Idade
14.
Cell Death Discov ; 1: 15058, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27551484

RESUMO

Retinitis pigmentosa (RP) refers to a group of inherited retinal degenerations resulting form rod and cone photoreceptor cell death. The rod cell death due to deleterious genetic mutations has been shown to occur mainly through apoptosis, whereas the mechanisms and features of the secondary cone cell death have not been fully elucidated. Our previous study showed that the cone cell death in rd10 mice, an animal model of RP, involves necrotic features and is partly mediated by the receptor interacting protein kinase. However, the relevancy of necrotic cone cell death in human RP patients remains unknown. In the present study, we showed that dying cone cells in rd10 mice exhibited cellular enlargement, along with necrotic changes such as cellular swelling and mitochondrial rupture. In human eyes, live imaging of cone cells by adaptive optics scanning laser ophthalmoscopy revealed significantly increased percentages of enlarged cone cells in the RP patients compared with the control subjects. The vitreous of the RP patients contained significantly higher levels of high-mobility group box-1, which is released extracellularly associated with necrotic cell death. These findings suggest that necrotic enlargement of cone cells is involved in the process of cone degeneration, and that necrosis may be a novel target to prevent or delay the loss of cone-mediated central vision in RP.

15.
Horm Metab Res ; 47(3): 176-83, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25295420

RESUMO

Type 2 diabetes results from the failure of beta-cells to adequately compensate for insulin resistance. Although the reduction of beta-cell mass is because of increased cell death and/or inadequate replication or neogenesis, the mechanism underlying beta-cell mass reduction is not fully understood. Here, we clarify the role of insulin signaling pathway in the beta-cell apoptosis using insulin resistant model mice. Wild-type mice and those carrying a mutation in the insulin receptor (mIR) were fed either regular chow or a high-fat diet for 6 weeks and subsequently investigated for beta-cell apoptosis, endoplasmic reticulum stress, and oxidative stress. Insulin tolerance tests revealed that mIR mice fed a high-fat diet (mIRHF) had higher insulin resistance. Beta-cell apoptosis was increased 2-fold in the wild-type mice fed a high-fat diet (wHF) compared with control mice, whereas beta-cell apoptosis in mIRHF mice did not increase compared with that in mIR mice. The expression of endoplasmic reticulum stress markers in isolated islets did not differ between the groups. Staining of 8-hydroxy-2'-deoxyguanosine and 4-hydroxy-2-nonenal in islets of wHF mice significantly increased, but the staining in mIRHF mice was not different from that in control group. Gene expression of the antioxidant enzyme MnSOD was significantly higher in mIRHF mice than those in the other 3 groups. A mutation in the insulin receptor attenuated the oxidative stress and apoptosis in beta-cells even though high caloric nutrient was loaded. Our results suggest that reduced insulin signaling protects beta-cells thorough decline of oxidative stress.


Assuntos
Apoptose , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Insulina/metabolismo , Mutação , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Receptor de Insulina/genética , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Masculino , Camundongos , Receptor de Insulina/metabolismo , Transdução de Sinais
16.
Br J Pharmacol ; 172(4): 1020-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25297838

RESUMO

BACKGROUND AND PURPOSE: Elevation of glutamate, an excitatory amino acid, during inflammation and injury plays a crucial role in the reception and transmission of sensory information via ionotropic and metabotropic receptors. This study aimed to investigate the mechanisms underlying the biphasic effects of metabotropic glutamate mGlu5 receptor activation on responses to noxious heat. EXPERIMENTAL APPROACH: We assessed the effects of intraplantar quisqualate, a non-selective glutamate receptor agonist, on heat and mechanical pain behaviours in mice. In addition, the effects of quisqualate on the intracellular calcium response and on membrane currents mediated by TRPV1 channels, were examined in cultured dorsal root ganglion neurons from mice. KEY RESULTS: Activation of mGlu5 receptors in hind paw transiently increased, then decreased, the response to noxious heat. In sensory neurons, activation of mGlu5 receptors potentiated TRPV1-mediated intracellular calcium elevation, while terminating activation of mGlu5 receptors depressed it. TRPV1-induced currents were potentiated by activation of mGlu5 receptors under voltage clamp conditions and these disappeared after washout. However, voltage-gated calcium currents were inhibited by the mGlu5 receptor agonist, even after washout. CONCLUSIONS AND IMPLICATIONS: These results suggest that, in sensory neurons, mGlu5 receptors biphasically modulate TRPV1-mediated intracellular calcium response via transient potentiation of TRPV1 channel-induced currents and persistent inhibition of voltage-gated calcium currents, contributing to heat hyper- and hypoalgesia.


Assuntos
Cálcio/metabolismo , Ácido Quisquálico/farmacologia , Receptor de Glutamato Metabotrópico 5/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Distúrbios Somatossensoriais/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Canais de Cálcio/fisiologia , Capsaicina/farmacologia , Células Cultivadas , Gânglios Espinais/citologia , Temperatura Alta , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Glutamato Metabotrópico 5/agonistas , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/fisiologia , Canais de Cátion TRPV/fisiologia
17.
Gene Ther ; 22(2): 127-37, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25503692

RESUMO

Age-related macular degeneration (AMD) is a vision-threatening disease characterized by choroidal fibrovascular membrane (FVM) formation, choroidal neovascularization (CNV) and choroidal fibrosis. No safe and effective therapeutic method has been developed for the choroidal fibrosis, although anti-vascular endothelial growth factor therapy can partially shrink the CNV. We recently reported that periostin (POSTN), which is produced by retinal pigment epithelial cells, has an important role in the formation of preretinal FVMs, but its role in choroidal FVMs has not been determined. In this study, we used Postn knockout mice to investigate the role played by POSTN in choroidal FVM formation. In addition, we used a new class of RNA interference (RNAi) agent (NK0144) that targets POSTN and determined its effect on choroidal FVM development. Genetic ablation of Postn had an inhibitory effect not only on CNV formation but also on choroidal fibrosis in a mouse CNV model. NK0144 also had a greater inhibitory effect on both the CNV and choroidal fibrosis than control RNAi with no apparent adverse effects. These findings suggest a causal relationship between POSTN and choroidal FVM formation, and also a potential therapeutic role of intravitreal NK0144 for AMD.


Assuntos
Moléculas de Adesão Celular/genética , Neovascularização de Coroide/terapia , Degeneração Macular/terapia , Interferência de RNA , Animais , Sequência de Bases , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Movimento Celular , Proliferação de Células , Células Cultivadas , Corioide/irrigação sanguínea , Corioide/patologia , Técnicas de Silenciamento de Genes , Terapia Genética , Humanos , Injeções Intravítreas , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Epitélio Pigmentado da Retina/patologia , Epitélio Pigmentado da Retina/fisiologia , Receptor 3 Toll-Like/metabolismo
18.
Eur J Gynaecol Oncol ; 35(4): 443-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25118489

RESUMO

In recent years, the incidence of therapy-related myelodysplastic syndrome (t-MDS) and therapy-related acute myeloid leukemia (t-AML) that occur during chemotherapy for ovarian cancer has increased. While alkylating agents and topoisomerase II inhibitors are particularly mutagenic and have strong leukemogenic potential, paclitaxel and combination chemotherapy/radiation therapy also appear to induce t-MDS. The present authors report a case of t-MDS that developed during chemotherapy and radiation therapy for ovarian cancer. The patient was a 75-year-old woman who received six courses of cyclophosphamide/doxorubicin/cisplatin (CAP) therapy after initial surgery for Stage IIIc grade ovarian cancer in 1995. Beginning in February 2005, the patient experienced multiple recurrences due to sternal metastasis. Chemotherapy, including paclitaxel and carboplatin (TC), was administered intermittently and was combined with radiation therapy to a sternal metastatic lesion. Pancytopenia was observed in December 2008, and she was diagnosed with t-MDS (WHO subtype, refractory cytopenias with multilineage dysplasia [RCMD]): the time from first chemotherapy to t-MDS onset was 106 months. Without evidence of blast crisis, the recurrent lesions continued to grow and caused multiple cerebral infarctions, from which she eventually died. The cumulative doses of paclitaxel and carboplatin administered to this patient were 1,968 mg and 6,480 mg, respectively.


Assuntos
Neoplasias das Glândulas Suprarrenais/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Ósseas/terapia , Quimiorradioterapia/efeitos adversos , Leucemia Mieloide Aguda/etiologia , Neoplasias Hepáticas/terapia , Síndromes Mielodisplásicas/etiologia , Segunda Neoplasia Primária/etiologia , Neoplasias Ovarianas/terapia , Neoplasias das Glândulas Suprarrenais/secundário , Idoso , Neoplasias Ósseas/secundário , Carboplatina/administração & dosagem , Infarto Cerebral/etiologia , Evolução Fatal , Feminino , Humanos , Neoplasias Hepáticas/secundário , Células Neoplásicas Circulantes , Neoplasias Ovarianas/patologia , Paclitaxel/administração & dosagem
19.
AJNR Am J Neuroradiol ; 35(7): 1371-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24610902

RESUMO

BACKGROUND AND PURPOSE: The natural history and therapeutic management of dissecting vertebrobasilar aneurysms without ischemic or hemorrhagic stroke (nonstroke dissecting vertebrobasilar aneurysms) are not well-established. We conservatively followed patients with nonstroke dissecting vertebrobasilar aneurysms and evaluated the factors related to clinical and morphologic deterioration. MATERIALS AND METHODS: One hundred thirteen patients were enrolled and divided by clinical presentation at diagnosis: asymptomatic (group 1, n = 52), pain only (group 2, n = 56), and mass effect (group 3, n = 5). Patients were conservatively managed without intervention and antithrombotic therapy. Clinical outcomes and morphologic changes were analyzed. RESULTS: A total of 113 patients who were diagnosed with nonstroke dissecting vertebrobasilar aneurysm had a mean follow-up of 2.9 years (range, 27 days to 8 years). Throughout that period, 1 patient in group 1 (1.9%) and 1 patient in group 2 (1.8%) showed clinical deterioration due to mass effect, and 1 patient in group 3 (20%) developed ischemic stroke followed by subarachnoid hemorrhage. Most patients (97.3%) were clinically unchanged. Three patients who had clinical deterioration showed aneurysm enlargement (P < .001). Aneurysms remained morphologically unchanged in 91 patients (80.5%). Aneurysm enlargement was seen in 5 patients (4.4%); risk of enlargement was significantly associated with either maximum diameter (hazard ratio = 1.30; 95% CI, 1.11-11.52; P = .001) or aneurysm ≥10 mm (hazard ratio = 18.0; 95% CI, 1.95-167; P = .011). CONCLUSIONS: The natural course of these lesions suggests that acute intervention is not always required and close follow-up without antithrombotic therapy is reasonable. Patients with symptoms due to mass effect or aneurysms of >10 mm may require treatment.


Assuntos
Dissecção Aórtica/terapia , Aneurisma Intracraniano/terapia , Dor/prevenção & controle , Dissecação da Artéria Vertebral/terapia , Insuficiência Vertebrobasilar/terapia , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Angiografia Cerebral , Progressão da Doença , Feminino , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Dor/diagnóstico , Dor/etiologia , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento , Dissecação da Artéria Vertebral/complicações , Dissecação da Artéria Vertebral/diagnóstico por imagem , Insuficiência Vertebrobasilar/complicações , Insuficiência Vertebrobasilar/diagnóstico por imagem
20.
Cell Death Differ ; 21(2): 270-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23954861

RESUMO

There is no known treatment for the dry form of an age-related macular degeneration (AMD). Cell death and inflammation are important biological processes thought to have central role in AMD. Here we show that receptor-interacting protein (RIP) kinase mediates necrosis and enhances inflammation in a mouse model of retinal degeneration induced by dsRNA, a component of drusen in AMD. In contrast to photoreceptor-induced apoptosis, subretinal injection of the dsRNA analog poly(I : C) caused necrosis of the retinal pigment epithelium (RPE), as well as macrophage infiltration into the outer retinas. In Rip3(-/-) mice, both necrosis and inflammation were prevented, providing substantial protection against poly(I : C)-induced retinal degeneration. Moreover, after poly(I : C) injection, Rip3(-/-) mice displayed decreased levels of pro-inflammatory cytokines (such as TNF-α and IL-6) in the retina, and attenuated intravitreal release of high-mobility group box-1 (HMGB1), a major damage-associated molecular pattern (DAMP). In vitro, poly(I : C)-induced necrosis were inhibited in Rip3-deficient RPE cells, which in turn suppressed HMGB1 release and dampened TNF-α and IL-6 induction evoked by necrotic supernatants. On the other hand, Rip3 deficiency did not modulate directly TNF-α and IL-6 production after poly(I : C) stimulation in RPE cells or macrophages. Therefore, programmed necrosis is crucial in dsRNA-induced retinal degeneration and may promote inflammation by regulating the release of intracellular DAMPs, suggesting novel therapeutic targets for diseases such as AMD.


Assuntos
Inflamação/metabolismo , Necrose/metabolismo , Poli I-C/farmacologia , RNA de Cadeia Dupla/farmacologia , Receptores de Reconhecimento de Padrão/metabolismo , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Animais , Apoptose , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Serina-Treonina Quinases de Interação com Receptores/deficiência , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Receptores de Reconhecimento de Padrão/efeitos dos fármacos , Epitélio Pigmentado da Retina/patologia
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