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We had cases in which peripheral neuropathy was augmented after changing from mFOLFOX6, a chemotherapy for colorectal cancer, to FOLFIRI and comparatively examined disease status and trends. There were no shared points with respect to patient characteristics, timing of peripheral neuropathy augmentation, drug dosage, etc. It appeared that the change in chemotherapy itself had an effect on neuropathic symptoms. Regarding the change in chemotherapy, the therapeutic agent was switched from oxaliplatin to irinotecan; the cause was unknown, but some effects of these two drugs were suggested. Future investigation, including the examination of genetic mutations, is necessary.
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Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Colorretais , Doenças do Sistema Nervoso Periférico , Camptotecina , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila , Humanos , Leucovorina , Compostos Organoplatínicos , Doenças do Sistema Nervoso Periférico/induzido quimicamenteRESUMO
An easily obtainable thiol-selective labeling reagent [18F]FBSEM (N-[2-(4-[18F]fluoro-N-methylbenzenesulfonamido)ethyl]maleimide) was developed. The advantage of the design is that the precursor and [18F]FBSEM have the same backbone and backbone construction is not required; in contrast, known thiol-specific labeling reagents do require backbone construction, and this is thought to be the cause of their complicated synthesis. [18F]FBSEM was successfully obtained in higher yield (25%) and in a simpler way (two fluorination and deprotection steps in 65 min) than the widely used [18F]FBEM (N-[2-(4-[18F]fluorobenzamide)ethyl]maleimide). The labeling efficacy of [18F]FBSEM was confirmed by conjugation with glutathione. [18F]FBSEM is a promising labeling agent for proteins.
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Radioisótopos de Flúor/química , Glutationa/análogos & derivados , Maleimidas/química , Proteínas/química , Compostos de Sulfidrila/química , Derivados de Benzeno/química , Reação de Cicloadição , Halogenação , Indicadores e Reagentes , Marcação por IsótopoRESUMO
Febrile neutropenia(FN)is one of the serious treatment-related toxicities after FEC100(5-fluorouracil 500mg/m2, epiru- bicin 100mg/m2, cyclophosphamide 500 mg/m2)chemotherapy for breast cancer. Granulocyte-colony stimulating factor(GCSF) is used as a support therapy for FN. Thus, we evaluated retrospectively the safety of administering pegfilgrastim the day after FEC100 chemotherapy in Japanese patients with breast cancer as compared with lenograstim. Grade 3 or 4 neutropenia was observed in 91.7% patients after pegfilgrastim administration and in 63.2% after lenograstim. The incidence rate of FN was 7.0%after pegfilgrastim administration and 9.7%after lenograstim, a difference that was not significantly different(p= 0.741). The mean relative dose intensity was good at 0.98 for pegfilgrastim and 0.97 for lenograstim. In conclusion, pegfilgrastim is not inferior to lenograstim in the incidence of FN. However, we do not recommend administering pegfilgrastim on the day after FEC100 therapy because it causes more severe neutropenia and has a high risk of FN. The timing of administration of pegfilgrastim in FEC100 therapy requires further study.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Neutrófilos/citologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Epirubicina/administração & dosagem , Feminino , Filgrastim , Fluoruracila/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Humanos , Contagem de Leucócitos , Pessoa de Meia-Idade , Neutropenia/prevenção & controle , Polietilenoglicóis , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Estudos RetrospectivosRESUMO
A 73-year-old woman with lung adenocarcinoma (cT4N3M1a: Stage IVA) was treated with atezolizumab as the eighth line of therapy. Four weeks after the fourth dose of atezolizumab, the prothrombin time (PT) and activated thromboplastin time (APTT) were prolonged. Coagulation factor V (FV) activity was decreased, and FV inhibitors were observed. There was no history of PT or APTT prolongation or bleeding before the use of atezolizumab. Atezolizumab-induced coagulation FV inhibitor was diagnosed. After 2 weeks, the PT and APTT spontaneously normalized. FV activity improved and the FV inhibitors disappeared after 6 and 9 weeks, respectively.
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In the treatment of B-cell non-Hodgkin lymphoma (B-NHL) rituximab improves long-term survival in combination with conventional chemotherapy. However, because the majority of patients with B-NHL eventually relapse, the development of more effective therapies is needed. Here, we evaluated the antitumor effects of a combination treatment involving sepantronium bromide (YM155), a first-in-class survivin suppressant, and rituximab in B-NHL xenograft mice models. To determine the efficacy of the combination treatment, YM155- and rituximab-treated B-NHL cell xenografted mice were monitored for tumor size and survival and subjected to 2'-deoxy-2'-(18)F-fluoro-D-glucose ((18)F-FDG) and 3'-(18)F-fluoro-3'-deoxythymidine ((18)F-FLT) positron emission tomography (PET) imaging. In addition, the cell proliferation status of excised tumors was examined by Ki-67 immunohistochemistry. In DB, WSU-DLCL-2, and Mino xenograft-bearing mice, the combination treatment of YM155 and rituximab induced significant tumor growth inhibition and tumor regression compared with either single agent. On day 3 after the initiation of treatment a significant decrease in both (18)F-FDG and (18)F-FLT tumor uptake from pretreatment levels was observed in combination treatment groups. The Ki-67 proliferation index was significantly decreased on day 3 in the xenograft models treated with combination treatment, suggesting that the combination of YM155 and rituximab reduced cell proliferation and glucose metabolism. Furthermore, compared with monotherapy, combination treatment prolonged survival times of severe combined immunodeficient mice with disseminated WSU-FSCCL and Jeko B-NHL tumors. Our findings demonstrate that YM155 and rituximab combination treatment enhances antitumor activity in B-NHL xenografts, and (18)F-FLT and (18)F-FDG PET imaging may allow the early functional evaluation of treatment responses in patients with B-NHL.
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Anticorpos Monoclonais Murinos/administração & dosagem , Antineoplásicos/administração & dosagem , Imidazóis/administração & dosagem , Linfoma de Células B/tratamento farmacológico , Naftoquinonas/administração & dosagem , Animais , Linhagem Celular Tumoral , Quimioterapia Combinada , Feminino , Humanos , Linfoma de Células B/diagnóstico por imagem , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Camundongos SCID , Cintilografia , Rituximab , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
A 44-year-old woman was hospitalized with a 2-day history of cough, sputum, and fever. There was no history of atopic dermatitis or asthma. On admission, the chest X-ray revealed scattered infiltration in the left upper lung fields. Further examination revealed peripheral blood and bronchoalveolar lavage fluid eosinophilia. Transbronchial lung biopsy revealed eosinophilic pneumonia, with eosinophil infiltration of the alveoli, destroyed basal lumina, and connecting intraluminal fibrosis of the alveolar walls. Based on the findings, we made the diagnosis of chronic eosinophilic pneumonia. Treatment with prednisolone at 60 mg/day resulted in dramatic improvement of both the symptoms and the radiologic abnormalities.
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Anti-Inflamatórios/administração & dosagem , Eosinófilos/patologia , Prednisolona/administração & dosagem , Alvéolos Pulmonares/patologia , Eosinofilia Pulmonar/tratamento farmacológico , Eosinofilia Pulmonar/patologia , Adulto , Lavagem Broncoalveolar , Eosinófilos/imunologia , Feminino , Fibrose , Humanos , Eosinofilia Pulmonar/imunologiaRESUMO
BACKGROUND: Disinhibition is sometimes experienced during bronchoscopy with sedation. However, data on disinhibition during bronchoscopy are scarce. We examined the prevalence and characteristics of disinhibition during bronchoscopy with midazolam. METHODS: This retrospective study analyzed consecutive patients who underwent bronchoscopy between November 2019 and December 2020. The severity of disinhibition was defined as follows: mild, disinhibition sometimes requiring restraints by assistants; moderate, disinhibition always requiring restraints by assistants; and severe, disinhibition requiring antagonization of sedation by flumazenil to continue bronchoscopy. RESULTS: Among 251 eligible patients who were sedated using midazolam, 36 (14.3%; 95% confidence interval [CI], 10.5%-19.2%), 42 (16.7%; 95% CI, 12.6%-21.8%), and 7 (2.8%; 95% CI, 1.4%-5.6%) experienced mild, moderate, and severe disinhibition, respectively. Depression (odds ratio [OR] 2.77; 95% CI, 1.20-6.41), endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) (OR 10.23; 95% CI, 1.02-103.01, referred to brushing/bronchial washing/observation), and increased administration of midazolam (OR 1.20; 95% CI, 1.02-1.42, per 1-mg increase) were independently associated with moderate-to-severe disinhibition. Patients experiencing moderate disinhibition reported significantly better scores for discomfort during bronchoscopy. Besides the maximum systolic and diastolic blood pressures during bronchoscopy, the changes in hemodynamic and respiratory statuses during bronchoscopy or complications did not significantly differ between patients experiencing moderate-to-severe disinhibition and those experiencing none-to-mild disinhibition. CONCLUSIONS: Moderate-to-severe disinhibition occurred in 19.5% of patients during bronchoscopy with midazolam. We should focus on disinhibition when patients have depression or are planning to undergo EBUS-TBNA, and sparing the administration of midazolam might reduce the occurrence of disinhibition. CLINICAL TRIAL REGISTRATION: UMIN000038571.
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Broncoscopia , Midazolam , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Humanos , Midazolam/efeitos adversos , Prevalência , Estudos RetrospectivosRESUMO
Ethambutol-induced optic neuropathy (EON) is a well-known complication, although low-dose ethambutol seldom causes EON. An 85-year-old man with non-tuberculous mycobacterial lung disease was taking antibiotics, including low-dose ethambutol. On day 85 of treatment, the diagnosis of EON was made. Despite prior discontinuation, his best corrected visual acuity drastically deteriorated from 20/17 (right eye) and 20/20 (left eye) to 20/330 (right eye) and 20/1,000 (left eye) within 3 weeks, and this symptom did not resolve. To our knowledge, there have been no reported cases with drastically progressing and irreversible EON even after the withdrawal of low-dose and short-term ethambutol.
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Etambutol , Doenças do Nervo Óptico , Idoso de 80 Anos ou mais , Antituberculosos/efeitos adversos , Etambutol/efeitos adversos , Olho , Humanos , Masculino , Doenças do Nervo Óptico/induzido quimicamente , Doenças do Nervo Óptico/diagnósticoRESUMO
PURPOSE: The recent development in radiosynthesis of the (11)C-carbamate function increases the potential of [(11)C]GR103545, which for the last decade has been regarded as promising for imaging the kappa-opioid receptor (kappa-OR) with PET. In the present study, [(11)C]GR103545 was evaluated in awake rhesus macaques. Separate investigations were performed to clarify the OR subtype selectivity of this compound. METHODS: Regional brain uptake kinetics of [(11)C]GR103545 was studied 0-120 min after injection. The binding affinity and opioid subtype selectivity of [(11)C]GR103545 was determined in cells transfected with cloned human opioid receptors. RESULTS: In vitro binding assays demonstrated a high affinity of GR103545 for kappa-OR (K(i) = 0.02 +/- 0.01 nM) with excellent selectivity over mu-OR (6 x 10(2)-fold) and) delta-OR (2 x 10(4)-fold). PET imaging revealed a volume of distribution (V(T)) pattern consistent with the known distribution of kappa-OR, with striatum = temporal cortex > cingulate cortex > frontal cortex > parietal cortex > thalamus > cerebellum. CONCLUSION: [(11)C]GR103545 is selective for kappa-OR and holds promise for use to selectively depict and quantify this receptor in humans by means of PET.
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Macaca mulatta , Piperazinas/metabolismo , Pirrolidinas/metabolismo , Receptores Opioides kappa/metabolismo , Vigília , Animais , Radioisótopos de Carbono , Tomografia por Emissão de Pósitrons , Traçadores Radioativos , Especificidade por SubstratoRESUMO
Herein, we report a pediatric case of acute paradoxical cerebral embolism complicated by serious acute pulmonary embolism that was caused by an extremely small patent foramen ovale (PFO). The patient had no medical history suggestive of any other reason. Paradoxical cerebral embolism may occur even with an extremely small PFO because of the increased right-side pressure of the heart and a resulting right-to-left shunt from the acute pulmonary embolism. Although pediatric cases of pulmonary embolism are rare, when diagnosed, clinicians should consider the risk of a concurrent paradoxical cerebral embolism resulting from a latent PFO. The possibility of PFO should be assessed extremely carefully in pediatric critical care by checking for a thrombogenesis tendency and the existence of deep vein thrombosis in the patient.
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UNLABELLED: H+/peptide transporter, PEPT1, is functionally expressed in some human cancer cell lines and might be a candidate molecular target for detection of cancers in vivo using PET. The aim of the present study was to establish a novel tumor-imaging technology using a PET tracer targeted to H+/peptide transporter(s). We also compared the tracer with 18F-FDG, focusing on the specificity of their accumulation between tumor and inflammatory tissues. METHODS: A dipeptide PET tracer, 11C-glycylsarcosine (11C-Gly-Sar), was injected intravenously into athymic mice transplanted with human pancreatic, prostate, and gastric cancer cells. The distribution patterns of 11C-Gly-Sar and 18F-FDG in the tumor-bearing mice, and in mice with inflammatory tissue, were assessed by imaging with a positron planar imaging system (PPIS). Tissue distributions of tracer radioactivity were also measured. The expression levels of PEPT1 and PEPT2 (PEPTs) proteins in tumor xenografts and inflammatory tissue were examined by immunohistochemical analysis. The messenger RNA expression levels of PEPTs in 58 available cancer cell lines were quantified by means of real-time polymerase chain reaction. RESULTS: All 3 tumor xenografts were well visualized with the PPIS after injection of 11C-Gly-Sar. Expression of PEPTs in those xenografts was confirmed by immunohistochemical analysis. Tumor-to-blood concentration ratios of 11C-Gly-Sar increased in a time-dependent manner and were much higher than unity. Most of the radioactivity found in the tumor tissue was recovered as the intact tracer. These results indicated that 11C-Gly-Sar was taken up by the PEPTs in tumor xenografts. It is noteworthy that 11C-Gly-Sar was minimally present in inflammatory tissues that expressed no PEPT1 or PEPT2 protein, whereas 18F-FDG was highly accumulated, with the values of the selectivity index being >25.1 and 0.72 for 11C-Gly-Sar and 18F-FDG, respectively. The mRNAs of PEPT1 and PEPT2 were expressed in 27.6% and 93.1%, respectively, of the cancer cell lines examined in the present study. CONCLUSION: The present study indicates that 11C-Gly-Sar is a promising tumor-imaging agent and is superior to 18F-FDG for distinguishing between tumors and inflammatory tissue. Because PEPTs were ubiquitously expressed in various types of tumor cells examined, 11C-Gly-Sar could be useful for the detection of many types of cancers.
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Radioisótopos de Carbono , Dipeptídeos , Neoplasias Experimentais/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Simportadores/análise , Animais , Linhagem Celular Tumoral , Dipeptídeos/farmacocinética , Fluordesoxiglucose F18/farmacocinética , Imuno-Histoquímica , Masculino , Camundongos , Transportador 1 de Peptídeos , Simportadores/genética , Distribuição TecidualRESUMO
UNLABELLED: The purpose of the present study was to measure adenosine A(2A) receptor (A(2A)R) occupancy in the brain by a novel adenosine A(1)/A(2A) antagonist, 5-[5-amino-3-(4fluorophenyl)pyrazin-2-yl]-1-isopropylpyridine-2(1H)-one (ASP5854), and to determine the degree of receptor occupancy necessary to inhibit haloperidol-induced catalepsy in rhesus monkeys. METHODS: A(2A)R occupancy by ASP5854 (0.001-0.1 mg/kg) was examined in the striatum using an A(2A)R-specific radiotracer, (11)C-SCH442416, and PET in conscious rhesus monkeys. A(2A)R occupancy was monitored after a single intravenous administration of ASP5854 in 3 animals, and a dynamic PET scan was performed at 1, 4, and 8 h after an intravenous bolus injection of the tracer for approximately 740 MBq. Catalepsy was induced by haloperidol (0.03 mg/kg, intramuscularly) and examined for incidence and duration. RESULTS: ASP5854 dose-dependently increased A(2A)R occupancy in the striatum and showed long-lasting occupancy even after the reduction of plasma concentration. Haloperidol induced severe catalepsy at 40 min after intramuscular injection. The incidence and duration of cataleptic posture were dose-dependently reduced by ASP5854 at 1 h after oral administration, and the minimum ED(50) value was 0.1 mg/kg. Administration of a dose of 0.1 mg/kg yielded a plasma concentration of 97 +/- 16.3 ng/mL, which corresponded to 85%-90% of A(2A)R occupancy. CONCLUSION: These results showed that ASP5854 antagonized A(2A)R in the striatum, and the dissociation from A(2A)R was relatively slow. In addition, more than 85% A(2A)R occupancy by ASP5854 resulted in an inhibition of haloperidol-induced catalepsy. Thus, such a pharmacodynamic study directly demonstrates both the kinetics of a drug in the brain and the relationship between dose-dependent receptor occupancy and plasma level.
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Antagonistas do Receptor A1 de Adenosina , Aminopiridinas/metabolismo , Corpo Estriado/metabolismo , Piperazinas/metabolismo , Receptor A2A de Adenosina/metabolismo , Antagonistas do Receptor A2 de Adenosina , Aminopiridinas/uso terapêutico , Animais , Radioisótopos de Carbono , Catalepsia/induzido quimicamente , Catalepsia/tratamento farmacológico , Corpo Estriado/diagnóstico por imagem , Haloperidol , Macaca mulatta , Masculino , Piperazinas/uso terapêutico , Tomografia por Emissão de Pósitrons , Pirazóis/metabolismo , Pirimidinas/metabolismoRESUMO
OBJECTIVE: This study assessed whether hyperglycemia and lipopolysaccharide (LPS) decrease the depression effect of interleukin (IL) 8 production by hypothermia in endothelial cells. DESIGN AND SETTING: Laboratory study in a university laboratory. SUBJECTS: Human umbilical vein endothelial cells (HUVECs). INTERVENTIONS: HUVECs were cultivated in various concentrations of glucose (5.5 or 16.5mM = 100 or 300mg/dl) with or without LPS stimulation for 5, 12, or 24h at either 30 degrees or 37 degrees C. RESULTS: After culturing, IL-8 mRNA expressions and IL-8 levels were measured. At 37 degrees C, hyperglycemia significantly increased basal IL-8 mRNA at 12h and basal IL-8 at 24h. At 37 degrees C hyperglycemia significantly increased LPS-stimulated IL-8 mRNA at 12h and LPS-stimulated IL-8 at 12 and 24h. At 30 degrees C basal IL-8mRNA, basal IL-8, and LPS-stimulated IL-8 were significantly decreased by hypothermia, but these hypothermic effects were not observed in LPS-stimulated IL-8 mRNA. Furthermore even at 30 degrees C hyperglycemia significantly increased LPS-stimulated IL-8 mRNA at all time points and LPS stimulated IL-8 at 24h. CONCLUSIONS: Hypothermia (30 degrees C) decreases the production of IL-8 in HUVECs but does not decrease the expression of IL-8 mRNA. When hypothermia is followed by hyperglycemia and LPS stimulation, such a combination may expose the patients to a high risk of secondary tissue damage during therapeutic hypothermia.
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Células Endoteliais/fisiologia , Hiperglicemia/metabolismo , Hipotermia/metabolismo , Interleucina-8/biossíntese , Lipopolissacarídeos/metabolismo , Expressão Gênica , Humanos , Interleucina-8/genética , Veias UmbilicaisRESUMO
Acetaminophen is absorbed rapidly after oral intake, and serum concentration peaks within 4 hours. The Rumack-Matthew (RM) nomogram is widely used to identify the potential risk of liver dysfunction. However, the RM nomogram was intended for use only when a single agent was ingested. We report the case of a patient with overdose ingestion of an over-the-counter combination cold medication that contained acetaminophen, where the patient's serum concentration increased over time. Over-the-counter combination cold medications are designed to relieve cold symptoms. However, the possibility that other agents that were present in the drug may change gastrointestinal kinetics should also be considered. The risk of liver dysfunction cannot be accurately determined from a single serum acetaminophen concentration measurement. Because of the risk of a delayed increase in the serum acetaminophen concentration, monitoring for liver dysfunction and developing a treatment strategy that includes N-acetylcysteine are required. This case report is targeted to clinical physicians who treat patients with acetaminophen overdose resulting from ingestion of multiple agents, and it reviews points of consideration when using the RM nomogram in acute intoxication.
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Acetaminofen/sangue , Analgésicos não Narcóticos/sangue , Overdose de Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/sangue , Combinação de Medicamentos , Humanos , Masculino , Fatores de Tempo , Adulto JovemRESUMO
INTRODUCTION: Sepantronium bromide (YM155) is a survivin suppressant that induces apoptosis in tumor cells. Although YM155 induces tumor regression in various tumor types in vivo, phase I and II studies demonstrated responding and non-responding patient populations. We investigated 11C-labeled YM155 ([11C]YM155) used as a positron emission tomography (PET) tracer to assess whether tumor uptake of [11C]YM155 correlated with its anti-tumor effect, thereby allowing identification of patients who would respond to YM155 treatment. METHODS: (1) Uptake of YM155 was measured in 39 human cancer cell lines in vitro using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). (2) In vivo tumor uptake was assessed in xenografted mice and total body distribution was evaluated in a cynomolgus monkey using [11C]YM155 with PET/computed tomography (CT) (mice) and PET (monkey) imaging. RESULTS: Intracellular uptake of YM155 in human cancer cell lines correlated well with its in vitro efficacy measured by GI50 (Pearson's râ¯=â¯-0.5709). Similarly, in vivo studies using tumor xenografted mice showed that tumors sensitive to YM155 demonstrated robust uptake of [11C]YM155, whereas insensitive tumors demonstrated low uptake. In the monkey, the biodistribution of [11C]YM155 indicated low accumulation in lung, breast, head, and neck and was only significant in organs involved with drug clearance: i.e. liver, kidneys, and bladder. CONCLUSIONS: Robust uptake of [11C]YM155 by a tumor appears to be a positive predictive marker for a good response to YM155. The findings suggest the potential utility of PET/CT imaging with [11C]YM155 for selection of patients whose tumors are likely to respond to YM155. ADVANCES IN KNOWLEDGE: YM155 efficacy correlated closely with its in vitro intracellular uptake and uptake on [11C]YM155 PET imaging. [11C]YM155 PET may predict tumor sensitivity to YM155. IMPLICATIONS FOR PATIENT CARE: The concept that tumor response can be accurately predicted prior to chemotherapy should be exploited to improve cancer treatment outcomes through judicious patient selection. The small molecule sepantronium bromide (YM155), a survivin suppressant, has been developed for the treatment of several cancers, including non-Hodgkin lymphoma, lung cancer, and breast cancer. The preferentially high in vitro uptake of YM155 by YM155-sensitive cancer cells and the high in vivo uptake of [11C]YM155 in YM155-sensitive tumors demonstrated by PET imaging suggest the potential utility of performing [11C]YM155 PET to allow the identification of patients with YM155-sensitive tumors.
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Radioisótopos de Carbono , Imidazóis/farmacologia , Naftoquinonas/farmacologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Survivina/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Humanos , Imidazóis/metabolismo , Imidazóis/farmacocinética , Espaço Intracelular/metabolismo , Marcação por Isótopo , Macaca fascicularis , Masculino , Camundongos , Naftoquinonas/metabolismo , Naftoquinonas/farmacocinética , Distribuição Tecidual , Imagem Corporal TotalRESUMO
INTRODUCTION: The immunosuppressive agent FK506 (tacrolimus) has neuroprotective properties in an experimental model of cerebral ischemia. To improve the accuracy of clinical studies in acute stroke, a clinical dose setting should be based on the brain concentration, but not on the blood concentration of agents in humans. We have already established a measurement method using PET for FK506 concentration in the normal monkey brain, which could be applicable for human study; however, under ischemic conditions, in this study, we aimed to examine the brain concentration of FK506 in a monkey model of stroke. METHODS: Studies were performed on six male cynomolgus monkeys (Macaca fascicularis) and a middle cerebral artery (MCA) occlusion model was used. Regional cerebral blood flow (rCBF) was measured by an intravenous injection of [(15)O]H(2)O 165 min after MCA occlusion. FK506 (0.1 mg/kg) containing [(11)C]FK506 was intravenously injected into the monkeys 180 min after MCA occlusion, and dynamic PET images were acquired for 30 min after administration. FK506 concentrations in the brain were calculated in moles per liter (M) units using the specific activity of injected FK506. RESULTS: MCA occlusion produced ischemia, confirmed by rCBF measurement before the administration of [(11)C]FK506. Fifteen minutes after FK506 (0.1 mg/kg) administration, the concentrations in the contralateral and ipsilateral cortex were 22.4+/-6.4 and 19.7+/-4.0 ng/g, respectively. CONCLUSION: We successfully measured the brain concentration of FK506 in a monkey model of stroke. The difference between the contralateral and ipsilateral concentrations of FK506 was not significant. This characteristic that FK506 readily penetrates ischemic tissue as well as normal tissue might explain the neuroprotective effect of FK506 in the ischemic brain and is suitable for the treatment of stroke patients.
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Imunossupressores/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Acidente Vascular Cerebral/diagnóstico por imagem , Tacrolimo/farmacocinética , Animais , Isquemia Encefálica/complicações , Lateralidade Funcional , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Injeções Intravenosas , Macaca fascicularis , Masculino , Tomografia por Emissão de Pósitrons , Acidente Vascular Cerebral/etiologiaRESUMO
Sodium-dependent glucose cotransporter 2 (SGLT2) is a pharmacological target of type 2 diabetes mellitus. The aim of this study was to noninvasively visualize the pharmacological action of a selective SGLT2 inhibitor ipragliflozin in the kidney using positron emission tomography (PET) imaging with 11C-methyl-d-glucoside (11C-MDG), an SGLT-specific radio-labeled substrate. PET imaging with 11C-MDG in vehicle-treated rats demonstrated that intravenously injected 11C-MDG substantially accumulated in the renal cortex, reflecting that the compound was reabsorbed by SGLTs. In contrast, ipragliflozin-treated rats showed significantly lower uptake of 11C-MDG in renal cortex in a dose-related manner, suggesting that ipragliflozin inhibited the renal reabsorption of 11C-MDG. This method of visualizing the mode of action of an SGLT2 inhibitor in vivo has demonstrated the drug's mechanism in reducing renal glucose reabsorption in kidney in living animals.
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PURPOSE: Nectin-4 is selectively overexpressed in a variety of cancers and is currently under clinical investigation as a therapeutic target. A monoclonal antibody against nectin-4 (AGS-22M6) was evaluated as an Immuno-positron emission tomography (ImmunoPET) reagent. Its ability to assay nectin-4 expression as well as detect nectin-4 positive tumors in the liver and bone was evaluated using mouse models. PROCEDURES: The biodistribution of [(89)Zr]AGS-22M6 was evaluated in mice bearing tumors with varying levels of nectin-4 expression. An isogenic breast cancer tumor line was used to model metastatic liver and bone disease in mice. The biodistribution of [(18)F]AGS-22M6 in cynomolgus monkeys was evaluated. RESULTS: A positive correlation was demonstrated between tumor nectin-4 expression and [(89)Zr]AGS-22M6 uptake. Tumors in the liver and bone were detected and differentiated based on nectin-4 expression. [(18)F]AGS-22M6 showed limited uptake in cynomolgus monkey tissues. CONCLUSIONS: [(89)Zr]AGS-22M6 is a promising ImmunoPET reagent that can assay nectin-4 expression in both primary and metastatic lesions.
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Anticorpos Monoclonais/imunologia , Moléculas de Adesão Celular/imunologia , Tomografia por Emissão de Pósitrons/métodos , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Neoplasias Ósseas/secundário , Linhagem Celular Tumoral , Humanos , Imuno-Histoquímica , Indicadores e Reagentes , Neoplasias Hepáticas/secundário , Macaca fascicularis , Camundongos , Nectinas , Distribuição Tecidual , Zircônio/químicaRESUMO
UNLABELLED: Although (18)F-FDG PET is an established technique to assess brain glucose use, a shorter imaging time is preferable for patient convenience and increased throughput. The aim of this study was to validate a brain (18)F-FDG PET protocol more rapid than the conventional protocol. METHODS: For comparison of normalized metabolic activities, brain (18)F-FDG PET was performed on 60 healthy subjects and 25 patients with probable Alzheimer's disease (AD), and an additional 20 healthy subjects served as a control group to assess diagnostic performance between the conventional and rapid scanning protocols. Conventional scans were acquired for a total of 20 min (a 10-min emission and a 10-min transmission). Immediately after conventional scanning, rapid scanning was performed for a total of 4 min (a 3-min emission and a 1-min transmission). PET images were anatomically standardized using NEUROSTAT, with pixel values normalized to the individual global value. Two database sets, from the 2 protocols, were compared by regional values and pixel-by-pixel analysis. A receiver-operating-characteristic analysis was performed for comparison of diagnostic accuracy between the 2 protocols. A kinetic simulation study was also performed to examine the possible difference due to the time lag between the protocols. RESULTS: Although small differences in normalized activity were found in several regions in the healthy subjects between the 2 protocols, no significant difference was found in any region in the patient group. The coefficients of variation of the normalized activity were 20%-30% larger in the rapidly scanned images, but the mean z images and their coefficient-of-variation images did not differ. The kinetic simulation study suggested that the differences were caused by the time lag between the 2 protocols. No significant differences were found in area under the receiver-operating-characteristic curves, and the diagnostic accuracies for the detection of AD were virtually equal between the 2 protocols. CONCLUSION: The rapid scanning protocol used in the present study could provide results nearly equivalent to data from the conventional protocol. Thus, it is feasible to use this rapid protocol to detect AD, without losing diagnostic accuracy.
Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Fluordesoxiglucose F18 , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Idoso , Idoso de 80 Anos ou mais , Inteligência Artificial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de TempoRESUMO
Two different electrolyte salts, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and a room temperature ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMITFSI), were incorporated into network polymers to obtain ion-conductive polymer electrolytes. Network polymers of poly(ethylene oxide-co-propylene oxide) (P(EO/PO)) and poly(methyl methacrylate) (PMMA) were chosen as matrixes for LiTFSI and EMITFSI, respectively. Both of the polymer electrolytes were single-phase materials and were completely amorphous. Ionic conductivity of the polymer electrolytes was measured over a wide temperature range, with the lowest temperatures close to or below the glass transition temperatures (Tg). The Arrhenius plots of the conductivity for both of the systems exhibited positively curved profiles and could be well fit to the Vogel-Tamman-Fulcher (VTF) equation. The conductivity of the PMMA/EMITFSI electrolytes was higher at most by 3 orders of magnitude than that of the LiTFSI/P(EO/ PO) electrolytes at ambient temperature. When the ideal glass transition temperature, T0 (one of the VTF fitting parameters), was compared with the Tg, a difference in the ionic conduction was apparent in these systems. In the P(EO/PO)/LiTFSI electrolytes, the T0 and Tg increased in parallel with salt concentration and the T0 was lower than the Tg by ca. 50 degrees C. On the contrary, the difference between the T0 and the Tg increased with increasing content of PMMA in the PMMA/EMITFSI electrolytes, with the observed difference in the concentration range studied reaching up to ca. 100 degrees C. The conductivity at the Tg, sigma(Tg), for the LiTFSI/P(EO/PO) electrolytes was on the order of 10(-14-)10(-13) S cm(-1) and increased with increasing salt concentration, whereas that for the PMMA/EMITFSI polymer electrolytes reached 10(-7) S cm(-1) when the concentration of PMMA was high. The ion transport mechanism was discussed in terms of the concepts of coupling/decoupling and strong/fragile for the two different polymer electrolytes.