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4.
ESMO Open ; 6(6): 100325, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34839104

RESUMO

BACKGROUND: Anti-programmed cell death protein 1 (PD-1) antibody monotherapy (PD1) has led to favorable responses in advanced non-acral cutaneous melanoma among Caucasian populations; however, recent studies suggest that this therapy has limited efficacy in mucosal melanoma (MCM). Thus, advanced MCM patients are candidates for PD1 plus anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) combination therapy (PD1 + CTLA4). Data on the efficacy of immunotherapy in MCM, however, are limited. We aimed to compare the efficacies of PD1 and PD1 + CTLA4 in Japanese advanced MCM patients. PATIENTS AND METHODS: We retrospectively assessed advanced MCM patients treated with PD1 or PD1 + CTLA4 at 24 Japanese institutions. Patient baseline characteristics, clinical responses (RECIST), progression-free survival (PFS), and overall survival (OS) were estimated using Kaplan-Meier analysis, and toxicity was assessed to estimate the efficacy and safety of PD1 and PD1 + CTLA4. RESULTS: Altogether, 329 patients with advanced MCM were included in this study. PD1 and PD1 + CTLA4 were used in 263 and 66 patients, respectively. Baseline characteristics were similar between both treatment groups, except for age (median age 71 versus 65 years; P < 0.001). No significant differences were observed between the PD1 and PD1 + CTLA4 groups with respect to objective response rate (26% versus 29%; P = 0.26) or PFS and OS (median PFS 5.9 months versus 6.8 months; P = 0.55, median OS 20.4 months versus 20.1 months; P = 0.55). Cox multivariate survival analysis revealed that PD1 + CTLA4 did not prolong PFS and OS (PFS: hazard ratio 0.83, 95% confidence interval 0.58-1.19, P = 0.30; OS: HR 0.89, 95% confidence interval 0.57-1.38, P = 0.59). The rate of ≥grade 3 immune-related adverse events was higher in the PD1 + CTLA4 group than in the PD1 group (53% versus 17%; P < 0.001). CONCLUSIONS: First-line PD1 + CTLA4 demonstrated comparable clinical efficacy to PD1 in Japanese MCM patients, but with a higher rate of immune-related adverse events.


Assuntos
Melanoma , Neoplasias Cutâneas , Idoso , Antígeno CTLA-4 , Humanos , Imunoterapia/métodos , Japão , Melanoma/tratamento farmacológico , Estudos Retrospectivos
6.
Skin Health Dis ; 1(3): e37, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35663139

RESUMO

Background: Deficiency of DNA mismatch repair (MMR) induces microsatellite instability (MSI). Pembrolizumab, an antibody targeting PD-1 (an immune checkpoint inhibitor), is more effective against MMR-deficient tumours than against MMR-proficient tumours. The status of MMR is a useful biomarker for predicting the effectiveness of pembrolizumab administration. Although the status of MMR has attracted attention in skin tumours, there are few reports on MSI in extramammary Paget's disease (EMPD). Objectives: To evaluate the status of MMR in patients with EMPD. Materials & Methods: One hundred one patients with EMPD were included. MMR status of the genomic DNA of each subject was analysed using Promega panel (approved as a companion diagnostic agent for the administration of pembrolizumab). Results: MSI testing showed the occurrence rates of MSI-high (more than two markers are unstable), MSI-low (one marker is unstable) and MSS (all markers are stable) tumour tissues were 0% (0/101), 1.0% (1/101) and 99.0% (100/101), respectively. Conclusion: The status of MMR may not be useful for the potential therapeutic application of pembrolizumab.

7.
Ann Oncol ; 31(9): 1198-1206, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32522691

RESUMO

BACKGROUND: Acral melanoma (AM) is an epidemiologically and molecularly distinct entity that is underrepresented in clinical trials on immunotherapy in melanoma. We aimed to analyze the efficacy of anti-programmed cell death 1 (anti-PD-1) antibodies in advanced AM. PATIENTS AND METHODS: We retrospectively evaluated unresectable stage III or stage IV AM patients treated with an anti-PD-1 antibody in any line at 21 Japanese institutions between 2014 and 2018. The clinicobiologic characteristics, objective response rate (ORR, RECIST), survival estimated using Kaplan-Meier analysis, and toxicity (Common Terminology Criteria for Adverse Events 4.0.) were analyzed to estimate the efficacy of the anti-PD-1 antibodies. RESULTS: In total, 193 patients (nail apparatus, 70; palm and sole, 123) were included in the study. Anti-PD-1 antibody was used as first-line therapy in 143 patients (74.1%). Baseline lactate dehydrogenase (LDH) was within the normal concentration in 102 patients (52.8%). The ORR of all patients was 16.6% (complete response, 3.1%; partial response, 13.5%), and the median overall survival (OS) was 18.1 months. Normal LDH concentrations showed a significantly stronger association with better OS than abnormal concentrations (median OS 24.9 versus 10.7 months; P < 0.001). Although baseline characteristics were similar between the nail apparatus and the palm and sole groups, ORR was significantly lower in the nail apparatus group [6/70 patients (8.6%) versus 26/123 patients (21.1%); P = 0.026]. Moreover, the median OS in this group was significantly poorer (12.8 versus 22.3 months; P = 0.03). CONCLUSIONS: Anti-PD-1 antibodies have limited efficacy in AM patients. Notably, patients with nail apparatus melanoma had poorer response and survival, making nail apparatus melanoma a strong candidate for further research on the efficacy of novel combination therapies with immune checkpoint inhibitors.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Japão , Melanoma/tratamento farmacológico , Receptor de Morte Celular Programada 1 , Estudos Retrospectivos , Neoplasias Cutâneas/tratamento farmacológico
9.
Neuropathol Appl Neurobiol ; 46(2): 111-124, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31179566

RESUMO

AIMS: Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown. METHODS: We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases. RESULTS: Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression-free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in-situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte-lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD-L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%). CONCLUSIONS: The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/imunologia , Linhagem da Célula/imunologia , Germinoma/diagnóstico , Germinoma/imunologia , Neoplasias Encefálicas/metabolismo , Perfilação da Expressão Gênica , Germinoma/metabolismo , Humanos , Prognóstico , Transcriptoma , Microambiente Tumoral/imunologia
10.
J Eur Acad Dermatol Venereol ; 34(8): 1715-1721, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31838771

RESUMO

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare malignant skin cancer. One of the hallmarks of cancers, including EMPD, is an enhancement of aerobic glycolysis, which is also known as the Warburg effect. In the last step of glycolysis, the enzyme lactate dehydrogenase A (LDHA) catalyzes the conversion of pyruvate to lactic acid, the accumulation of which contributes to the creation of an acidic tumour microenvironment. This in turn results in immunosuppression in various types of cancers. However, the contribution of these pathways has not been well-studied in EMPD. OBJECTIVE: To investigate the significance of the Warburg effect and its contribution to the tumour immune microenvironment in EMPD. METHODS: The mRNA expression levels of molecules involved in glycolysis and immune-related cytokines were examined by ddPCR. The number of immune cells was assessed by immunohistochemistry (IHC). RESULTS: The levels of two glycolytic enzymes, HK2 and LDHA, in tumour tissues were significantly increased compared to those in paired-normal tissues. IHC analyses revealed increased numbers of PD-L1+ , PD-1+ , CD163+ M2 macrophages, Iba1+ macrophages and Foxp3+ Tregs that were associated with high LDHA levels in EMPD. ddPCR demonstrated that multiple cytokines including IL-4, IL-6, IL-10, TGF-ß and CCL-2 were upregulated and associated with high LDHA levels in EMPD. Statistical analyses showed that IL-6 mRNA expression correlated with the number of CD163+ , Iba-1+ and Foxp3+ cells. CONCLUSION: The Warburg effect contributes to immunomodulation in the tumour microenvironment and further elucidation may lead to better understanding of the pathogenesis of EMPD.


Assuntos
L-Lactato Desidrogenase/genética , Doença de Paget Extramamária/imunologia , Microambiente Tumoral , Humanos , Imuno-Histoquímica , Doença de Paget Extramamária/genética
12.
Br J Dermatol ; 181(3): 505-511, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30706452

RESUMO

BACKGROUND: Although carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (CYFRA) are useful markers for extramammary Paget disease (EMPD), serum CEA and CYFRA levels are not elevated in most patients with EMPD without metastasis. Cell-free (cf)DNA has attracted attention as an indicator of clinical conditions in several cancers. OBJECTIVES: To identify further useful biomarkers for the detection of EMPD, including early lesions, and to study the clinical implications of cfDNA in EMPD. METHODS: cfDNA were isolated from serum of patients with EMPD with and without metastasis, and from healthy volunteers. Serum extracts were amplified using polymerase chain reaction. RESULTS: Serum cfDNA levels were significantly elevated in patients with EMPD with or without metastasis compared with those in healthy controls. Serum cfDNA was a better diagnostic marker for the presence of EMPD than serum CYFRA. Moreover, the postoperative serum cfDNA levels were significantly lower than those from the preoperative samples, and the change in serum cfDNA levels reflected the clinical courses of patients with EMPD treated with chemotherapy. CONCLUSIONS: Taking the evidence together, serum cfDNA levels may be a useful marker for diagnosis and disease progression in EMPD. What's already known about this topic? Serum levels of carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (CYFRA) are not elevated in most patients with extramammary Paget disease (EMPD) without metastasis. Cell-free (cf)DNA has attracted attention as an indicator of clinical conditions in several cancers. There are few reports of the clinical implications of cfDNA in dermatology. What does this study add? Serum cfDNA levels were significantly elevated in patients with EMPD with or without metastasis compared with those in healthy controls. Postoperative serum cfDNA levels were significantly lower than those from the preoperative samples. Changes in serum cfDNA levels reflected the clinical courses of patients with EMPD treated with chemotherapy. What is the translational message? Serum cfDNA levels in patients with EMPD are a useful marker for the detection of EMPD, including localized EMPD. Changes in serum cfDNA levels in an individual patient may reflect the clinical course of EMPD.


Assuntos
Biomarcadores Tumorais/sangue , Ácidos Nucleicos Livres/sangue , Doença de Paget Extramamária/diagnóstico , Neoplasias Cutâneas/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Queratina-19/sangue , Masculino , Pessoa de Meia-Idade , Doença de Paget Extramamária/sangue , Doença de Paget Extramamária/genética , Doença de Paget Extramamária/cirurgia , Período Pós-Operatório , Período Pré-Operatório , Pele/patologia , Neoplasias Cutâneas/sangue , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/cirurgia , Adulto Jovem
13.
Transplant Proc ; 50(10): 4053-4056, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30577313

RESUMO

Post-transplant lymphoproliferative disorder (PTLD) is a well-recognized and potentially fatal complication of cardiac transplantation that commonly involves the gastrointestinal tract. Herein, we report a case of life-threatening gastrointestinal bleeding from recurrent terminal ileac ulcers mimicking PTLD in a heart recipient treated with everolimus (EVL). A 40-year-old man underwent heart transplantation for dilated cardiomyopathy 3 years prior to the current admission and was treated with tacrolimus and EVL. He was admitted to a local hospital because of fever, abdominal pain, and diarrhea. His symptoms persisted and, 3 weeks later, hematochezia occurred; thus, he was transferred to our hospital. As computed tomography and 18F-fluorodeoxyglucose positron emission tomography showed bowel-wall thickening of the terminal ileum, gastrointestinal PTLD was initially suspected. However, although colonoscopy- performed after switching EVL to mycophenolate mofetil (MMF)-showed terminal ileac ulcers, the histologic examination revealed no findings corresponding to PTLD. As EVL may delay ulcer healing, MMF was maintained for 3 months. After repeated colonoscopy showed ulcer healing, MMF was switched back to EVL for cardiac allograft vasculopathy prevention. Three weeks later, he was emergently admitted to a local hospital for life-threatening gastrointestinal bleeding from a recurrent terminal ileal ulcer, which required hemostatic forceps hemostasis. As EVL is suspected to be associated with recurrent ileal ulcers, EVL was again switched back to MMF. The ileal ulcers resolved, without recurrence in 3 months of clinical follow-up. This case demonstrates that cases of life-threatening gastrointestinal bleeding from recurrent terminal ileac ulcers can mimic PTLD in a heart recipient treated with EVL.


Assuntos
Everolimo/efeitos adversos , Transplante de Coração/efeitos adversos , Doenças do Íleo/induzido quimicamente , Doenças do Íleo/diagnóstico , Transtornos Linfoproliferativos/diagnóstico , Adulto , Diagnóstico Diferencial , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/efeitos adversos , Masculino , Ácido Micofenólico/uso terapêutico , Tacrolimo/uso terapêutico , Úlcera/diagnóstico , Úlcera/etiologia
14.
Transplant Proc ; 50(9): 2726-2732, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401385

RESUMO

BACKGROUND: Left ventricular assist device (LVAD) therapy is the "gold standard" alternative therapy for patients with advanced heart failure. However, LVAD therapy is still uncommon in the Asia-Pacific region. Therefore, we aimed to elucidate the clinical outcomes of patients from Japan supported with the HeartMate II (HM-II) LVAD at our institution. METHODS: Ninety-two patients (mean 44.3 ± 12.1 years, 68 men, average body mass index 1.65 ± 0.28 m2; 81 with nonischemic cardiomyopathy) who underwent HM-II implantation for bridge to transplantation (n = 91) or for destination therapy in a clinical study (n = 1) at the National Cerebral and Cardiovascular Center between April 2013 and October 2017 were enrolled in this analysis. Preoperatively, most patients (n = 73, 79%) had an INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) profile of between level 2 and 4. Postoperatively, the average pump speed was 8602 ± 258 rpm and the hemodynamics were well compensated. RESULTS: Adverse events consisted of 38 (41.3%) hemolysis, 30 (32.6%) major infection, 27 (29.3%) major bleeding (6 [6.5%] with gastrointestinal bleeding), and 18 (19.6%) neurologic dysfunction events. Eighteen patients underwent heart transplantation (HTx) after an average of 32.9 ± 8.9 months of VAD support, and overall survival at both 6 months and 3 years was 96.3%. CONCLUSION: Clinical outcome among patients with HM-II at our institution is satisfactory for both survival and adverse events. The HM-II can provide effective hemodynamic support during the extremely long waiting period for HTx in Japan.


Assuntos
Insuficiência Cardíaca/cirurgia , Coração Auxiliar , Adolescente , Adulto , Idoso , Feminino , Coração Auxiliar/efeitos adversos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
15.
Transplant Proc ; 50(3): 947-949, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29661467

RESUMO

INTRODUCTION: Tuberculous paradoxical reactions (PRs) are excessive immune reactions occurring after antituberculosis (TB) treatment and are commonly observed in immunocompromised hosts such as patients infected with the human immunodeficiency virus. CASE REPORT: We recently encountered a 63-year-old male heart transplant recipient who developed tuberculous PR after treatment for miliary TB. The patient had been receiving immunosuppressive therapy with cyclosporine and mycophenolate mofetil for over 15 years. The diagnosis of miliary TB was made based on the presence of intermittent fever and fatigue; thus, anti-TB treatments (isoniazid, levofloxacin, ethambutol, and pyrazinamide) were started, which led to rapid defervescence and regression of the granular shadow and pleural effusion. However, a new persistent fever and confused state developed 1 month after the anti-TB therapy was started. After excluding possible etiologies of the patient's symptom, a PR was suspected, and anti-TB drugs were continued; corticosteroids were added as anti-inflammatory agents. After that, he has shown a favorable course with long-term anti-TB chemotherapy. CONCLUSION: A PR should always be considered when the patients' symptoms of tuberculosis re-exacerbate after an appropriate anti-TB therapy. A PR commonly occurs in patients with various immunologic conditions including heart transplant recipients.


Assuntos
Antituberculosos/efeitos adversos , Transplante de Coração , Complicações Pós-Operatórias/induzido quimicamente , Tuberculose Miliar/tratamento farmacológico , Antituberculosos/uso terapêutico , Ciclosporina/efeitos adversos , Ciclosporina/uso terapêutico , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/uso terapêutico , Isoniazida/efeitos adversos , Isoniazida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/microbiologia , Tuberculose Miliar/imunologia , Tuberculose Miliar/microbiologia
16.
Biomed Opt Express ; 9(2): 387-396, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29552380

RESUMO

Label-free visualization of nerves and nervous plexuses will improve the preservation of neurological functions in nerve-sparing robot-assisted surgery. We have developed a coherent anti-Stokes Raman scattering (CARS) rigid endoscope to distinguish nerves from other tissues during surgery. The developed endoscope, which has a tube with a diameter of 12 mm and a length of 270 mm, achieved 0.91% image distortion and 8.6% non-uniformity of CARS intensity in the whole field of view (650 µm diameter). We demonstrated CARS imaging of a rat sciatic nerve and visualization of the fine structure of nerve fibers.

17.
Transplant Proc ; 49(10): 2415-2418, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29198694

RESUMO

BACKGROUND: Reversible cerebral vasoconstriction syndrome (RCVS) is a transient cerebrovascular disorder putatively caused by some immunosuppressive agents. CASE REPORT: We recently encountered a 47-year-old female patient diagnosed with dilated cardiomyopathy who developed RCVS after heart transplantation. A triple-drug regimen consisting of tacrolimus, mycophenolate mofetil, and a corticosteroid was started after surgery. On postoperative day (POD) 11, the patient developed a severe headache, although computed tomography of the head demonstrated no signs of hemorrhage or infarction. At first, both a painkiller and migraine drugs were regularly administered to the patient. On POD 21, however, she developed an unbearable headache with a visual field defect and mild hemiparesis of the right hand. Magnetic resonance imaging (MRI) of the brain revealed a cerebral infarction in the left occipital lobe with diffuse vasoconstriction of both the middle and posterior cerebral arteries. A diagnosis of RCVS was made and tacrolimus, a drug suspected to cause RCVS, was discontinued. In its place, two doses of basiliximab followed by everolimus, both of which are alternatives for tacrolimus, were given. The corticosteroid dose was also increased. Furthermore, to release vasoconstriction, both verapamil and diltiazem were administered. On POD 27, cerebrovascular constrictions were shown to be relieved on brain MRI and the patient's neurological symptoms subsequently almost completely diminished. CONCLUSION: RCVS should always be considered as a cause of headache in heart transplant recipients because tacrolimus, an immunosuppressive agent, may trigger RCVS. This will allow rapid intervention that is essential for avoiding irreversible neurological deficits.


Assuntos
Transplante de Coração , Imunossupressores/efeitos adversos , Tacrolimo/efeitos adversos , Vasoespasmo Intracraniano/induzido quimicamente , Feminino , Cefaleia/etiologia , Humanos , Pessoa de Meia-Idade
18.
Br J Dermatol ; 177(2): 456-469, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28078663

RESUMO

BACKGROUND: Angiosarcoma is a rare malignant neoplasm derived from endothelial cells, and because advanced angiosarcoma is resistant to standard chemotherapy its prognosis is poor. Therefore, new therapies are urgently needed. Heat shock protein (HSP)90 has been identified as a molecular chaperone that regulates various cancer-related proteins. Numerous clinical trials are currently testing the effectiveness of HSP90 inhibitors in various types of malignancies. OBJECTIVES: To investigate the role of HSP90 in the pathogenesis of angiosarcoma and whether the inhibition of HSP90 may have antitumour activity. METHODS: The expression of HSP90 protein in angiosarcoma was examined using immunohistochemistry and immunoblotting. The effects of HSP90 inhibition were proven using proliferation, migration and invasion assay in angiosarcoma cells. The mechanism of antitumour effect by HSP90 inhibition was investigated by the transfection of small interfering RNA (siRNA). RESULTS: The levels of HSP90 protein expression in cultured angiosarcoma cell lines were markedly increased compared with those in normal tissue cell lines. Immunohistochemical analyses revealed that the expression of HSP90 protein was strongly detected in angiosarcoma tissues compared with that in normal dermal vessels or senile angioma tissues. Ganetespib, an HSP90 inhibitor, with or without taxanes, inhibited the proliferation of angiosarcoma cells via apoptosis in a dose-dependent manner. HSP90 siRNA suppressed the proliferation, migration and invasion of angiosarcoma cells. Knock-down of HSP90 did not suppress vascular endothelial growth factor receptor 2 directly, but selectively suppressed several downstream targets of vascular endothelial growth factor signalling in angiosarcoma cells. CONCLUSIONS: HSP90 could be a novel therapeutic target for angiosarcoma.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Hemangiossarcoma/prevenção & controle , Transdução de Sinais/fisiologia , Neoplasias Cutâneas/prevenção & controle , Fator A de Crescimento do Endotélio Vascular/fisiologia , Anticarcinógenos/farmacologia , Antineoplásicos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Estudos de Casos e Controles , Movimento Celular/fisiologia , Transformação Celular Neoplásica , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Taxoides/farmacologia , Triazóis/farmacologia , Células Tumorais Cultivadas
19.
J Dent Res ; 95(13): 1528-1534, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27523626

RESUMO

Advanced glycation end-products (AGEs) are generated via nonenzymatic glycation of dentinal collagen, resulting in accumulation of AGEs in dentin tissue. Since accumulated AGEs cause crosslinking between amino acid polypeptides in the collagen molecule and modify mechanical properties of dentinal collagen, the authors assumed that there would be a significant interaction between the generation of AGEs and progression of caries in dentin. To confirm such an interaction, spectroscopic imaging analyses (i.e., nanosecond fluorescence lifetime imaging and second harmonic generation light imaging) were performed in addition to biochemical and electron microscopic analyses in the present study. Seven carious human teeth were fixed in paraformaldehyde and cut longitudinally into 1-mm sections using a low-speed diamond saw for the following analyses. In transmission electron microscopy (TEM) analysis, nondecalcified specimens were embedded in epoxy resin and sliced into thin sections for observation. For the immunohistochemical analysis, the specimens were paraffin embedded after decalcification for 2 wk and sectioned with a microtome. Resultant sections were stained with anti-AGE and anticollagen antibodies. The demineralized specimens were used for spectroscopic analyses without additional treatment. For Western blotting analysis, specimens were separated into carious and sound dentin. Each specimen was homogenized with a bead crusher and an ultrasonic homogenizer and then treated with hydrochloric acid. In carious dentin, the collagen fibers showed an amorphous structure in the TEM image, and the AGEs were localized in the areas of bacterial invasion in the immunostaining image. The total amount of AGEs in carious dentin was higher than in sound dentin in Western blotting. The ultrastructure of type I collagen and total amount of AGEs varied markedly in the dentinal caries region. The fluorescence lifetime was shorter in the carious area than that in the sound areas, indicating an increase of AGEs in the carious area. The increase of AGEs could influence the progression of dentinal caries.


Assuntos
Colágeno/metabolismo , Cárie Dentária/patologia , Dentina/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Western Blotting , Colágeno/ultraestrutura , Reagentes de Ligações Cruzadas , Dentina/ultraestrutura , Progressão da Doença , Fluorescência , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Reação de Maillard , Microscopia Eletrônica
20.
Sci Rep ; 6: 25950, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-27185264

RESUMO

This paper presents a new correlative bioimaging technique using Y2O3:Tm, Yb and Y2O3:Er, Yb nanophosphors (NPs) as imaging probes that emit luminescence excited by both near-infrared (NIR) light and an electron beam. Under 980 nm NIR light irradiation, the Y2O3:Tm, Yb and Y2O3:Er, Yb NPs emitted NIR luminescence (NIRL) around 810 nm and 1530 nm, respectively, and cathodoluminescence at 455 nm and 660 nm under excitation of accelerated electrons, respectively. Multimodalities of the NPs were confirmed in correlative NIRL/CL imaging and their locations were visualized at the same observation area in both NIRL and CL images. Using CL microscopy, the NPs were visualized at the single-particle level and with multicolour. Multiscale NIRL/CL bioimaging was demonstrated through in vivo and in vitro NIRL deep-tissue observations, cellular NIRL imaging, and high-spatial resolution CL imaging of the NPs inside cells. The location of a cell sheet transplanted onto the back muscle fascia of a hairy rat was visualized through NIRL imaging of the Y2O3:Er, Yb NPs. Accurate positions of cells through the thickness (1.5 mm) of a tissue phantom were detected by NIRL from the Y2O3:Tm, Yb NPs. Further, locations of the two types of NPs inside cells were observed using CL microscopy.

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