14 results on '"Oyama J"'
Search Results
2. In vitro effects of lapachol and β-lapachone against Leishmania amazonensis
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Ramos-Milaré, Á.C.F.H., primary, Sydor, B.G., additional, Brustolin, A.Á., additional, Lera-Nonose, D.S.S.L., additional, Oyama, J., additional, Silva, E.L., additional, Caetano, W., additional, Campanholi, K.S.S., additional, Demarchi, I.G., additional, Silveira, T.G.V., additional, and Lonardoni, M.V.C., additional
- Published
- 2023
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3. The DPP4 inhibitor linagliptin exacerbated heart failure due to energy deficiency via downregulation of glucose absorption and utilization in mice
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Shiraki, A, primary, Oyama, J, additional, Shimizu, T, additional, and Node, N, additional
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- 2022
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4. Late-life parkinsonism in bipolar disorder.
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Nishio Y, Amemiya K, and Oyama J
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- Humans, Female, Male, Aged, Middle Aged, Dopamine Plasma Membrane Transport Proteins metabolism, 3-Iodobenzylguanidine, Lewy Body Disease diagnostic imaging, Parkinson Disease complications, Parkinson Disease diagnostic imaging, Brain diagnostic imaging, Brain pathology, Brain metabolism, Levodopa therapeutic use, Biomarkers, Bipolar Disorder, Tomography, Emission-Computed, Single-Photon, Parkinsonian Disorders, Magnetic Resonance Imaging
- Abstract
Aim: Parkinsonism is a frequently encountered symptom in individuals with bipolar disorder (BD). It can be drug-induced, co-occurring with Parkinson's disease (PD), or a genuine motor abnormality of BD itself. This study aims to address the primary pathophysiology of parkinsonism in BD., Methods: Sixteen patients with BD and parkinsonism were recruited from consecutive patients who were referred to a neurology clinic at a tertiary psychiatric centre. The patients underwent clinical assessments, dopamine transporter single-photon computed tomography (DAT-SPECT), cardiac 123I-metaiodo-benzylguanidine (MIBG) scintigraphy, and morphometric magnetic resonance imaging (MRI). The positivity or negativity of Lewy body disease (LBD) biomarkers was determined based on the visual assessment of DAT-SPECT and heart-to-mediastinum ratio on cardiac MIBG scintigraphy. Four out of the 16 participants received 300-600 mg of levodopa., Results: Thirteen patients were diagnosed with BD type 1, and 12 had experienced >5 previous mood episodes. Parkinsonism developed more than 10 years after the onset of BD and after the age of 50 years in all patients. Four cases were positive for LBD biomarkers. Six patients with negative LBD biomarkers showed reduced striatal uptake with z-scores below -2.0. MRI morphometry revealed varying degrees of brain atrophy in most patients. Three of the four patients did not respond to 600 mg of levodopa., Conclusions: The results of this study indicate that the majority of parkinsonism observed in BD is not a consequence of PD/LBD. Instead, it may represent a genuine motor abnormality of BD in late life., (© 2025 Japanese Psychogeriatric Society.)
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- 2025
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5. Factors Associated With Rebleeding and Early Mortality Following Transcatheter Arterial Embolization for Spontaneous Muscle Hematoma: A Single-Center Experience Including the Period of the Coronavirus Disease Pandemic.
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Horii T, Kishino M, Morishita K, Kanda E, Takahashi M, Kimura K, Adachi T, Oyama J, Okawa S, and Tateishi U
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Objectives We aim to investigate factors associated with rebleeding and mortality within one month of transcatheter arterial embolization (TAE) for spontaneous muscle hematoma (SMH) and the impact of the novel coronavirus disease 2019 (COVID-19). Methods This retrospective analysis included 33 patients who underwent TAE for SMH at a single center between 2012 and 2022. After 2020, eight of these patients had the COVID-19 infection. Patient characteristics, laboratory findings, embolic materials, and imaging findings were compared between the rebleeding and non-rebleeding groups, as well as between the early mortality and survival groups. Results Among all patients, 72.7% were on anticoagulant therapy before the onset of SMH. Of these, 27.2% required retreatment due to rebleeding. Patients who experienced rebleeding were more likely to have a platelet count below 50,000/µL, fibrinogen levels below 150 mg/dL, and an activated partial thromboplastin time (APTT) ratio above 2.5. Patients with SMH unrelated to anticoagulants had a higher rebleeding rate (56%), which may serve as a predictor of rebleeding. No significant difference in rebleeding rates was observed between patients with and without COVID-19 infection. Early mortality within one month of onset occurred in 24.2% of patients, with a higher prevalence among those with a history of malignancy. However, there was no increase in early mortality among patients who required retreatment for rebleeding. Conclusions Patients with a low platelet count, fibrinogen level, prolonged APTT, and non-anticoagulant-related SMH are at a high risk of rebleeding and require close monitoring. Severe comorbidities, including malignancies and COVID-19, can affect mortality rates. TAE remained effective even in cases of rebleeding. Advances in knowledge This study indicated non-anticoagulant-related SMH and hematological parameters as factors associated with rebleeding., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. The Ethical Committee of Tokyo Medical and Dental University Hospital issued approval M2020-354. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Horii et al.)
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- 2024
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6. Brain perfusion SPECT in dementia: what radiologists should know.
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Imokawa T, Yokoyama K, Takahashi K, Oyama J, Tsuchiya J, Sanjo N, and Tateishi U
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- Humans, Cerebrovascular Circulation, Tomography, Emission-Computed, Single-Photon methods, Dementia diagnostic imaging, Brain diagnostic imaging, Brain blood supply
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The findings of brain perfusion single-photon emission computed tomography (SPECT), which detects abnormalities often before changes manifest in morphological imaging, mainly reflect neurodegeneration and contribute to dementia evaluation. A major shift is about to occur in dementia practice to the approach of diagnosing based on biomarkers and treating with disease-modifying drugs. Accordingly, brain perfusion SPECT will be required to serve as a biomarker of neurodegeneration. Hypoperfusion in Alzheimer's disease (AD) is typically seen in the posterior cingulate cortex and precuneus early in the disease, followed by the temporoparietal cortices. On the other hand, atypical presentations of AD such as the posterior variant, logopenic variant, frontal variant, and corticobasal syndrome exhibit hypoperfusion in areas related to symptoms. Additionally, hypoperfusion especially in the precuneus and parietal association cortex can serve as a predictor of progression from mild cognitive impairment to AD. In dementia with Lewy bodies (DLB), the differentiating feature is the presence of hypoperfusion in the occipital lobes in addition to that observed in AD. Hypoperfusion of the occipital lobe is not a remarkable finding, as it is assumed to reflect functional loss due to impairment of the cholinergic and dopaminergic systems rather than degeneration per se. Moreover, the cingulate island sign reflects the degree of AD pathology comorbid in DLB. Frontotemporal dementia is characterized by regional hypoperfusion according to the three clinical types, and the background pathology is diverse. Idiopathic normal pressure hydrocephalus shows apparent hypoperfusion around the Sylvian fissure and corpus callosum and apparent hyperperfusion in high-convexity areas. The cortex or striatum with diffusion restriction on magnetic resonance imaging in prion diseases reflects spongiform degeneration and brain perfusion SPECT reveals hypoperfusion in the same areas. Brain perfusion SPECT findings in dementia should be carefully interpreted considering background pathology., (© 2024. The Author(s).)
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- 2024
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7. Cryptogenic New-onset Refractory Status Epilepticus with Hyperintensity of T1-weighted Magnetic Resonance Imaging in the Bilateral Basal Ganglia: An Autopsy Report.
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Takahashi S, Ono D, Shintaku H, Oyama J, Nishida Y, Ishikawa K, and Yokota T
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We present a 76-year-old man with cryptogenic new-onset refractory status epilepticus (C-NORSE) with an initial abnormal signal in the nucleus accumbens and a remarkable hyperintense signal on T1-weighted magnetic resonance imaging in the bilateral basal ganglia (BG). His status epilepticus did not respond to most anti-epileptic therapies or immunotherapies, and he died of sepsis. An autopsy revealed severe neuronal loss and hypertrophic astrocytes in the BG and limbic system, with no signs of inflammation or malignancy. This case suggests that lesions in the BG may reflect secondary degeneration and predict poor outcomes in C-NORSE.
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- 2024
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8. Detection of Dural Defect Localization Using 4-Dimensional Dynamic Computed Tomography Myelography for Patients with Superficial Siderosis.
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Hashimoto M, Egawa S, Hirai T, Hashimoto J, Morishita S, Yamada K, Matsukura Y, Kaho R, Hada H, Oyama J, and Yoshii T
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- Humans, Male, Female, Middle Aged, Aged, Four-Dimensional Computed Tomography methods, Adult, Aged, 80 and over, Dura Mater diagnostic imaging, Myelography methods, Siderosis diagnostic imaging
- Abstract
Background: There are cases of superficial siderosis (SS) with spinal ventral fluid-filled collection in the spinal canal. In our previous study, the balanced steady-state free precession sequence magnetic resonance imaging is useful in identifying the location of dural defects. However, because of its narrow scan area and long scan time, it cannot easily detect the defect location in some patients with small dural defect. In this study, we applied 4-dimensional (4D) dynamic computed tomography (CT) imaging, including time-axis imaging, to myelography using the latest CT imaging equipment, which can perform short-time continuous imaging, to identify the dural defect site., Methods: Twenty SS patients with ventral fluid-filled collection in the spinal canal (9 males, 11 females; mean age 61.6 years) underwent 4D dynamic CT myelography. A 192-row helical CT (SOMATOM Force, SIEMENS, Munich, Germany) with high-speed scanning capability was used to obtain 9-11 scans per minute at low dose while passing contrast medium into the subarachnoid space. Then, contrast leakage sites were identified., Results: The contrast leakage sites could be identified in all 20 cases: C7/Th1, 2 cases; Th1/2, 5 cases; Th2/3, 9 cases; Th3/4, 1 case; Th5/6, 1 case; Th7/8, 1 case; and Th8/9, 1 case. Eighteen cases underwent surgical operation, and actual dural defects were confirmed at the contrast leakage sites. The mean ± standard deviation of leakage time from contrast agent injection was 19.0 ± 9.2 s., Conclusions: The 4D dynamic CT myelography can be used to reliably identify the location of spinal fluid leakage. In SS cases, dural defects could be visualized in an average of 19 seconds., (Copyright © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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9. Intracranial residual lesions following early intensification in a patient with T-cell acute lymphoblastic leukemia: a case report.
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Nagamatsu Y, Isoda T, Inaji M, Oyama J, Niizato D, Tomomasa D, Mitsuiki N, Yamashita M, Kamiya T, Imai K, Kanegane H, Morio T, and Takagi M
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- Humans, Male, Child, Brain Neoplasms diagnostic imaging, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Positron-Emission Tomography, Methionine, Precursor T-Cell Lymphoblastic Leukemia-Lymphoma, Neoplasm, Residual
- Abstract
Background: T-cell acute lymphoblastic leukemia (T-ALL) tends to involve central nervous system (CNS) infiltration at diagnosis. However, cases of residual CNS lesions detected at the end of induction and post early intensification have not been recorded in patients with T-ALL. Also, the ratio and prognosis of patients with residual intracranial lesions have not been defined., Case Presentation: A 9-year-old boy with T-ALL had multiple intracranial tumors, which were still detected post early intensification. To investigate residual CNS lesions, we used
11 C-methionine (MET)-positron emission tomography. Negative MET uptake in CNS lesions and excellent MRD status in bone marrow allowed continuing therapies without hematopoietic cell transplantation., Conclusions: In cases with residual lesions on imaging studies, treatment strategies should be considered by the systemic response, direct assessment of spinal fluid, along with further development of noninvasive imaging methods in CNS. Further retrospective or prospective studies are required to determine the prognosis and frequency of cases with residual intracranial lesions after induction therapy., (© 2024. The Author(s).)- Published
- 2024
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10. Case report: Recurring and treatment-resistant depression in acquired hepatocerebral degeneration due to a congenital portosystemic shunt.
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Tamura T, Takagi S, Hayakawa A, Oyama J, Fujino J, Shiwaku H, Takahashi H, and Sugihara G
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Introduction: Acquired hepatocerebral degeneration (AHD) is a neurological condition associated with cerebral manganese (Mn) accumulation caused by portosystemic shunts (PSS), usually because of advanced liver disease. AHD is diagnosed by the identification of T1-weighted brain magnetic resonance imaging (MRI) hyperintensities coupled with the presence of PSS and neurological symptoms. Clinical presentations primarily involve motor dysfunction and cognitive impairment. As a result of the frequently concurrent hepatic encephalopathy, the psychiatric symptoms of AHD alone remain unclear. This report is the first documentation of unique psychiatric symptoms of AHD due to a congenital PSS (CPSS) and suggests the efficacy of shunt embolization in achieving sustained remission of psychiatric symptoms in such cases., Methods: A 57-year-old Japanese woman presented with recurrent severe depression, pain, and somatosensory hallucinations, along with fluctuating motor dysfunction, including parkinsonism, and cognitive impairments. Psychiatric interventions, including antidepressants, antipsychotics or electroconvulsive therapy, had limited efficacy or did not prevent relapse., Results: T1-weighted MRI showed bilateral hyperintensity in the globus pallidus. No history of Mn exposure or metabolic abnormalities, including copper, was identified. Furthermore, no evidence of liver dysfunction or hyperammonemia was found. Eventually, a gastrorenal shunt was observed on contrast-enhanced abdominal computed tomography. The diagnosis of AHD due to CPSS was made based on the clinical manifestations and abnormal imaging findings. Shunt embolization was performed, which prevented the relapse of psychiatric symptoms and substantially reduced the T1-weighted MRI hyperintensities., Conclusions: This case highlights the potential involvement of AHD in adult-onset psychiatric symptoms, even in the absence of liver disease. Furthermore, this case underscores the efficacy of shunt embolization in treating the psychiatric symptoms of AHD due to CPSS., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Tamura, Takagi, Hayakawa, Oyama, Fujino, Shiwaku, Takahashi and Sugihara.)
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- 2024
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11. Increase in Cerebral Blood Flow After Catheter Ablation of Atrial Fibrillation.
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Takahashi Y, Yamamoto T, Oyama J, Sugihara G, Shirai Y, Tao S, Takigawa M, Sato H, Sasaki M, Hirakawa A, Takahashi H, Goya M, and Sasano T
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- Male, Humans, Middle Aged, Aged, Prospective Studies, Cerebrovascular Circulation, Atrial Fibrillation diagnostic imaging, Atrial Fibrillation surgery, Catheter Ablation adverse effects, Cognitive Dysfunction etiology
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Background: Recent studies have found that atrial fibrillation (AF) is a risk factor for cognitive impairment. Brain hypoperfusion is hypothesized as an underlying mechanism of cognitive decline in AF patients., Objectives: This study sought to assess changes in cerebral blood flow (CBF) and brain volume after catheter ablation of AF., Methods: Patients undergoing catheter ablation of AF were enrolled in this prospective study. AF patients being treated with pharmaceuticals alone served as a control group. Brain magnetic resonance imaging was performed before and 6 months after catheter ablation. CBF was assessed by 2-dimensional phase-contrast magnetic resonance angiography. Brain volume and bilateral hippocampal volume were measured using FreeSurfer software., Results: Of the 57 study patients (age 64 ± 11 years; 45 men; paroxysmal AF: n = 22; nonparoxysmal AF: n = 35), 48 patients were freed from tachyarrhythmia recurrence beyond a 3-month blanking period. Changes in CBF and brain perfusion over 6 months were significantly greater in the study patients than control (CBF: 39.26 vs -34.86 mL; P = 0.01, ANCOVA; brain perfusion: 3.78 vs -3.02 mL/100 mL/min; P = 0.009, ANCOVA), while changes in total brain volume and bilateral hippocampal volume were similar between 2 groups (total brain volume: 2.57 vs -2.15 mL; P = 0.32, ANCOVA; bilateral hippocampal volume: 0.03 vs 0.04 mL; P = 0.8, ANCOVA). Nonparoxysmal AF at baseline was an independent predictor of an increase in CBF of >32.6 mL/min., Conclusions: Catheter ablation of AF has favorable effects on CBF, particularly in nonparoxysmal AF. Our results may partially explain the association between cognitive decline and AF., Competing Interests: Funding Support and Author Disclosures Drs Takahashi and Takigawa have received research grants from Medtronic Japan, Boston Scientific, Japan Lifeline, and WIN International. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2022 American College of Cardiology Foundation. All rights reserved.)
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- 2022
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12. Detecting ossification of the posterior longitudinal ligament on plain radiographs using a deep convolutional neural network: a pilot study.
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Ogawa T, Yoshii T, Oyama J, Sugimura N, Akada T, Sugino T, Hashimoto M, Morishita S, Takahashi T, Motoyoshi T, Oyaizu T, Yamada T, Onuma H, Hirai T, Inose H, Nakajima Y, and Okawa A
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- Cervical Vertebrae diagnostic imaging, Humans, Neural Networks, Computer, Osteogenesis, Pilot Projects, Longitudinal Ligaments, Ossification of Posterior Longitudinal Ligament diagnostic imaging
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Background Context: Its rare prevalence and subtle radiological changes often lead to difficulties in diagnosing cervical ossification of the posterior longitudinal ligament (OPLL) on plain radiographs. However, OPLL progression may lead to trauma-induced spinal cord injury, resulting in severe paralysis. To address the difficulties in diagnosis, a deep learning approach using a convolutional neural network (CNN) was applied., Purpose: The aim of our research was to evaluate the performance of a CNN model for diagnosing cervical OPLL., Study Design and Setting: Diagnostic image study., Patient Sample: This study included 50 patients with cervical OPLL, and 50 control patients with plain radiographs., Outcome Measures: For the CNN model performance evaluation, we calculated the area under the receiver operating characteristic curve (AUC). We also compared the sensitivity, specificity, and accuracy of the diagnosis by the CNN with those of general orthopedic surgeons and spine specialists., Methods: Computed tomography was used as the gold standard for diagnosis. Radiographs of the cervical spine in neutral, flexion, and extension positions were used for training and validation of the CNN model. We used the deep learning PyTorch framework to construct the CNN architecture., Results: The accuracy of the CNN model was 90% (18/20), with a sensitivity and specificity of 80% and 100%, respectively. In contrast, the mean accuracy of orthopedic surgeons was 70%, with a sensitivity and specificity of 73% (SD: 0.12) and 67% (SD: 0.17), respectively. The mean accuracy of the spine surgeons was 75%, with a sensitivity and specificity of 80% (SD: 0.08) and 70% (SD: 0.08), respectively. The AUC of the CNN model based on the radiographs was 0.924., Conclusions: The CNN model had successful diagnostic accuracy and sufficient specificity in the diagnosis of OPLL., Competing Interests: Declaration of competing interests Support for this study was provided by Japan Agency for Medical Research and Development (JP21ek1126633)., (Copyright © 2022 Elsevier Inc. All rights reserved.)
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- 2022
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13. The anti-Leishmania potential of bioactive compounds derived from naphthoquinones and their possible applications. A systematic review of animal studies.
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Ramos-Milaré ÁCFH, Oyama J, Murase LS, Souza JVP, Guedes BS, Lera-Nonose DSSL, Monich MT, Brustolin AÁ, Demarchi IG, Teixeira JJV, and Lonardoni MVC
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- Animals, Animals, Laboratory, Humans, Antiprotozoal Agents therapeutic use, Leishmania, Leishmaniasis, Cutaneous drug therapy, Naphthoquinones chemistry, Naphthoquinones pharmacology
- Abstract
Leishmaniasis affects millions of people worldwide, and available treatments have severe limitations. Natural and derivative products are significant sources of innovative therapeutic agents. Naphthoquinones are natural or synthetic chemical compounds with broad biological activity. This systematic review aimed to evaluate the potential anti-Leishmania activity of bioactive compounds derived from naphthoquinones in animal models. Conducted in accordance with PRISMA guidelines, two blocks of MeSH terms were assembled: group I, Leishmania OR Leishmaniasis; group II, Atovaquone OR Lapachol OR Beta lapachone OR Naphthoquinones. The search was performed on PubMed, Web of Science, SCOPUS, EMBASE, and Lilacs databases. Twenty-four articles were retrieved and submitted for quality assessment using the SYRCLE critical appraisal tool. The in vivo anti-Leishmania potential of naphthoquinones was evaluated in visceral and cutaneous leishmaniasis using several measurement parameters. Analyzed compounds varied in structure, association with reference drugs, and encapsulation using a drug delivery system. The study design, including treatment protocol, differed between studies. The findings of the studies in this systematic review indicate the anti-Leishmania potential of naphthoquinones in vivo, with different treatment regimens directed against different Leishmania species. The employed drug delivery systems improve the results concerning selectivity, distribution, and required therapeutic dose. The immunomodulatory action was shown to be beneficial to the host, favoring an adequate immune response against infection by Leishmania parasites since it favored Th
1 responses. All studies presented a moderate to high risk of bias. These findings suggest that more studies are needed to assess the overall effectiveness and safety of these treatments., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2022
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14. Branch-like enhancement on contrast enhanced MRI is a specific finding of cerebellar lymphoma compared with other pathologies.
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Yokoyama K, Oyama J, Tsuchiya J, Karakama J, Tamura K, Inaji M, Tanaka Y, Kobayashi D, Maehara T, and Tateishi U
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- Diagnosis, Differential, Humans, Magnetic Resonance Imaging methods, Retrospective Studies, Brain Neoplasms pathology, Glioma pathology, Lymphoma diagnostic imaging, Lymphoma pathology
- Abstract
Branch-like enhancement (BLE) on contrast-enhanced (CE) magnetic resonance imaging (MRI) was found to be effective in differentiating primary central nervous system lymphoma (PCNSL) from high-grade glioma (HGG) in the cerebellum. However, whether it can be applied to assessments of secondary central nervous system lymphoma (SCNSL), or other cerebellar lesions is unknown. Hence, we retrospectively reviewed cerebellar masses to investigate the use of BLE in differentiating cerebellar lymphoma (CL), both primary and secondary, from other lesions. Two reviewers qualitatively evaluated the presence and degree of BLE on CE-T1 weighted imaging (T1WI). If multiple views were available, we determined the view in which BLE was the most visible. Seventy-five patients with the following pathologies were identified:17 patients with CL, 30 patients with metastasis, 12 patients with hemangioblastoma, 9 patients with HGG, and 7 patients with others. Twelve patients presented with PCNSL and five with SCNSL. Of 17 patients with CL, 15 (88%) had BLE, whereas three (5%) out of 58 patients in the non-CL group showed BLE. In patients who underwent three-dimensional-CE-T1WI, BLE was the most visible on the sagittal image. In conclusion, BLE is a highly specific finding for CL and the sagittal image is important in evaluating this finding., (© 2022. The Author(s).)
- Published
- 2022
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