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1.
Support Care Cancer ; 30(5): 3943-3954, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35044484

RESUMO

PURPOSE: This prospective post-marketing surveillance (PMS) was designed to collect data on the safety and effectiveness of naldemedine in routine clinical practice in patients with opioid-induced constipation (OIC) and cancer pain in Japan and explore the characteristics of patients prone to diarrhea. METHODS: The enrolled patients received naldemedine (0.2 mg, once a day) orally for up to 12 weeks. In the safety analysis, adverse drug reactions (ADRs), including diarrhea as a special interest, were assessed. Effectiveness was evaluated, especially regarding the frequency and condition of bowel movement. RESULTS: In the safety analysis set (n = 1177), 145 ADRs occurred in 133 (11.30%) patients, and diarrhea was the most frequent event (n = 107, 9.09%). Most cases of diarrhea were non-serious (98.1%). Most ADRs were non-serious (93.8%), and they resolved within 2 weeks (75.9%). No patient characteristics influenced the risk of diarrhea development or aggravation. Both the frequency (75.0% and 83.2%) and condition of bowel movement (80.0% and 88.0%) were improved at 2 and 12 weeks, respectively in the effectiveness analysis set (n = 953). Frequency and condition of bowel movement were also improved in patients excluded (e.g., Eastern Cooperative Oncology Group performance status was ≥ 3) or with very small numbers (e.g., received weak opioid) in the clinical trials. CONCLUSIONS: This PMS indicates that naldemedine is well tolerated and effective in patients of various backgrounds in routine clinical practice who have OIC and cancer pain. TRIAL REGISTRATION: UMIN000042851.


Assuntos
Dor do Câncer , Neoplasias , Constipação Induzida por Opioides , Analgésicos Opioides/efeitos adversos , Dor do Câncer/induzido quimicamente , Dor do Câncer/tratamento farmacológico , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológico , Constipação Intestinal/epidemiologia , Humanos , Japão , Naltrexona/análogos & derivados , Antagonistas de Entorpecentes/uso terapêutico , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Vigilância de Produtos Comercializados , Estudos Prospectivos
2.
Clin Infect Dis ; 72(11): e859-e867, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33103200

RESUMO

BACKGROUND: Baloxavir marboxil (baloxavir) is expected to reduce influenza transmission by rapid reduction of viral load. The incidence of household transmission was compared between index patients (IPs) treated with baloxavir and those treated with neuraminidase inhibitors. METHODS: Using a Japanese claims database, the first family members with influenza diagnosis during the 2018-2019 influenza season were identified as IPs, and the diagnosis date was designated day 1. According to the anti-influenza drug dispensed to the IP, their families were classified into the oral baloxavir group and 3 controls: oral oseltamivir group (a primary control), inhaled zanamivir group, and inhaled laninamivir group. A household transmission was defined as influenza diagnosed for any non-IP family members during days 3-8. The incidence of household transmission was compared between groups using a logistic regression model adjusting backgrounds of IPs. RESULTS: The proportion of families with household transmission was 17.98% (15 226 of 84 672) in the baloxavir group and 24.16% (14 983 of 62 004) in the oseltamivir group. The covariate-adjusted odds ratio (oseltamivir/baloxavir) was 1.09 (95% confidence interval [95% CI], 1.05-1.12), which indicated significantly lower incidence in the baloxavir group. The adjusted odds ratios (controls/baloxavir) against zanamivir and laninamivir were 0.93 (95% CI, .89-.97) and 0.99 (95% CI, .96-1.02), respectively. CONCLUSIONS: Baloxavir may contribute to reduction in household transmission compared with oseltamivir. In comparison between baloxavir and inhalants, a similar reduction was not shown and it might be due to unmeasured confounding by administration route differences.


Assuntos
Dibenzotiepinas , Influenza Humana , Orthomyxoviridae , Antivirais/uso terapêutico , Dibenzotiepinas/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Humanos , Influenza Humana/tratamento farmacológico , Seguro Saúde , Morfolinas/uso terapêutico , Neuraminidase , Oseltamivir/uso terapêutico , Piridonas/uso terapêutico , Triazinas
3.
Clin Infect Dis ; 73(5): e1181-e1190, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-33354728

RESUMO

BACKGROUND: Baloxavir marboxil (baloxavir) is a single-dose, oral antiinfluenza drug with a novel mechanism of action. We compared the incidence of hospitalization in patients treated with baloxavir vs neuraminidase inhibitors. METHODS: In this retrospective, observational, cohort study, we used real-world patient data extracted from a Japanese health insurance claims database. The enrollment period was 1 October 2018 to 17 April 2019. On day 1, eligible patients (N = 339 007) received baloxavir, oseltamivir, zanamivir, or laninamivir. Baseline characteristics were standardized using the inverse probability of treatment weighting method. The primary end point was the incidence of hospitalization (days 2-14). Secondary end points included antibacterial use, secondary pneumonia, and additional antiinfluenza drug use. RESULTS: Compared with the baloxavir group, the incidence of hospitalization was greater in the oseltamivir group (risk ratio [RR] and 95% confidence interval [CI], 1.41 [1.00-2.00]; risk difference [RD] and 95% CI, 0.06 [.01-.12]) and zanamivir group (RR, 1.85 [1.23-2.78]; RD, 0.11 [.02-.20]). Oseltamivir-treated patients were less likely to require antibacterials than baloxavir-treated patients (RR, 0.87 [.82-.91]). However, oseltamivir-treated patients were more likely to be hospitalized with antibacterials (RR, 1.70 [1.21-2.38]) or antibacterial injection (RR, 1.67 [1.17-2.38]) than baloxavir-treated patients (post hoc analysis). Compared with baloxavir-treated patients, additional antiinfluenza drug use was greater in oseltamivir-, zanamivir-, and laninamivir-treated patients (RR, 1.51 [1.05-2.18], 2.84 [2.04-3.96], and 1.68 [1.35-2.10], respectively). CONCLUSIONS: Baloxavir is an efficacious antiinfluenza treatment that may reduce hospitalization compared with oseltamivir and zanamivir. CLINICAL TRIALS REGISTRATION: University hospital Medical Information Network Clinical Trials Registry (UMIN000038159).


Assuntos
Dibenzotiepinas , Influenza Humana , Antivirais/uso terapêutico , Estudos de Coortes , Dibenzotiepinas/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Hospitalização , Humanos , Incidência , Influenza Humana/tratamento farmacológico , Influenza Humana/epidemiologia , Seguro Saúde , Morfolinas/uso terapêutico , Neuraminidase , Oseltamivir/uso terapêutico , Pacientes Ambulatoriais , Piridonas/uso terapêutico , Estudos Retrospectivos , Triazinas
4.
J Chem Ecol ; 45(11-12): 926-933, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31758292

RESUMO

Chemical examination of plant constituents responsible for oviposition by a Magnoliaceae-feeding butterfly, Graphium doson, was conducted using its major host plant, Michelia compressa. A methanol extract prepared from young leaves of the plant elicited a strong oviposition response from females. The methanolic extract was then separated by solvent partition into three fractions: CHCl3, i-BuOH, and aqueous fractions. Active substance(s) resided in both i-BuOH- and water-soluble fractions. Bioassay-guided further fractionation of the water-soluble substances by means of various chromatographic techniques led to the isolation of an oviposition stimulant. The stimulant was identified as D-(+)-pinitol on the basis of 13C NMR spectra and physicochemical properties. D-(+)-Pinitol singly exhibited a moderate oviposition-stimulatory activity at a dose of 150 µg/cm2. This compound was present also in another host plant, Magnolia grandiflora, in a sufficient amount to induce oviposition behavior of G. doson females. Certain cyclitols including D-(+)-pinitol have been reported to be involved in stimulation of oviposition by some Aristolochiaceae- and Rutaceae-feeding papilionid butterflies. A possible pathway of phytochemical-mediated host shifts in the Papilionidae, in which certain cyclitols could enact important mediators, is discussed in relation to the evolution of cyclitol biosynthesis in plants.


Assuntos
Magnolia/química , Oviposição/efeitos dos fármacos , Extratos Vegetais/química , Animais , Butanóis/química , Borboletas , Ciclitóis/química , Ciclitóis/metabolismo , Feminino , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Inositol/análogos & derivados , Inositol/química , Inositol/metabolismo , Magnolia/metabolismo , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Solubilidade , Água/química
5.
Eur Radiol ; 26(1): 55-63, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25994199

RESUMO

OBJECTIVES: To assess the optimal reconstruction phase and the image quality of coronary computed tomographic angiography (CCTA) in patients with atrial fibrillation (AF). METHODS: We performed CCTA in 60 patients with AF and 60 controls with sinus rhythm. The images were reconstructed in multiple phases in all parts of the cardiac cycle, and the optimal reconstruction phase with the fewest motion artefacts was identified. The coronary artery segments were visually evaluated to investigate their assessability. RESULTS: In 46 (76.7 %) patients, the optimal reconstruction phase was end-diastole, whereas in 6 (10.0 %) patients it was end-systole or mid-diastole, and in 2 (3.3 %) patients it was another cardiac phase. In 53 (88.3 %) of the controls, the optimal reconstruction phase was mid-diastole, whereas it was end-systole in 4 (6.7 %), and in 3 (5.0 %) it was another cardiac phase. There was a significant difference between patients with AF and the controls in the optimal phase (p < 0.01) but not in the visual image quality score (p = 0.06). CONCLUSIONS: The optimal reconstruction phase in most patients with AF was the end-diastolic phase. The end-systolic phase tended to be optimal in AF patients with higher average heart rates. KEY POINTS: The optimal reconstruction phase in 76.7 % of patients with atrial fibrillation (AF) was end-diastole. The end-systolic phase was optimal in AF patients with higher heart rates. ECG and heart-rate control are necessary to obtain end-diastolic images with fewer motion artefacts.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Idoso , Artefatos , Angiografia Coronária/métodos , Vasos Coronários/diagnóstico por imagem , Diástole/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/métodos , Estudos Prospectivos , Sístole/fisiologia
6.
Acta Radiol ; 57(3): 295-302, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25817455

RESUMO

BACKGROUND: Model-based type iterative reconstruction algorithms with fast reconstruction times are now available. The clinical feasibility of their reconstruction has not been evaluated adequately. PURPOSE: To investigate the effects of model-based type iterative reconstruction, i.e. iterative model reconstruction (IMR), with fast reconstruction time on the qualitative and quantitative image quality at low-dose chest computed tomography (CT). MATERIAL AND METHODS: Thirty-one patients undergoing low-dose screening chest CT were enrolled. Images were reconstructed using filtered back projection (FBP), hybrid iterative reconstruction (HIR), and IMR algorithms. The CT attenuation and image noise for all reconstructions were calculated at the lung apex, middle, and base. Using a 4-point scale, two reviewers visually evaluated the image quality with respect to vessel sharpness, streak artifact, the mediastinum, and the overall image quality of each reconstruction method. RESULTS: The mean estimated effective dose was 1.0 ± 0.3 mSv. There was no significant difference in the CT attenuation among the three reconstructions. The mean image noise of FBP, HIR, and IMR images was 124.3 ± 57.3, 34.8 ± 10.2, and 22.9 ± 5.8 HU, respectively. There were significant differences for all comparison combinations among the three methods (P < 0.01). The best subjective overall image quality for the lung and mediastinum was obtained with IMR (P < 0.01). The reconstruction time for IMR was within 3 min in all cases. CONCLUSION: At low-dose chest CT, IMR can improve the qualitative and quantitative visualization of both lung and mediastinal structures especially in the lung apex at a clinically acceptable reconstruction time. Its application may improve diagnostic performance.


Assuntos
Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Radiografia Torácica , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Variações Dependentes do Observador , Reprodutibilidade dos Testes
7.
Acta Radiol ; 56(11): 1308-14, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25348474

RESUMO

BACKGROUND: The 256-slice computed tomography (CT) scanners with wider detector coverage and faster gantry rotation speed are now available. The performance of scanners that feature a rotation speed of 270 ms at coronary CT angiography (CCTA) has not been evaluated in patients with a higher heart rate. PURPOSE: To evaluate the image quality of 256-slice CT with faster gantry rotation speed in patients undergoing CCTA. MATERIAL AND METHODS: We enrolled 886 patients; 357(40.3%) underwent study on a 64-slice CT at a rotation speed of 420 ms, the other 529 (59.7%) were examined using a 256-slice CT scanner at 270 ms. Two observers judged the image quality of 2658 imaged coronary arteries on a 4-point scale. RESULTS: The mean image quality score was significantly higher for the 256 - than the 64-slice CT scans (3.94 ± 0.28 vs. 3.73 ± 0.61; P < 0.01). There was no significant difference in the image quality scores between 64 - and 256-slice scans in patients whose heart rate (HR) was <60 bpm. However, in patients whose HR exceeded 60 bpm these scores were significantly higher for 256-slice CT images (P < 0.01). CONCLUSION: CCTA performed on the 256-slice CT scanner yielded significantly better image quality in patients with an HR exceeding 60 bpm.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Frequência Cardíaca/fisiologia , Tomografia Computadorizada por Raios X/métodos , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos
8.
J Comput Assist Tomogr ; 38(1): 131-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24424561

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effect of a low tube voltage technique and hybrid iterative reconstruction (HIR) on image quality at 3-dimensional computed tomographic angiography (3D-CTA) of the liver. METHODS: Before hepatic surgery, we randomly assigned 60 patients (17 women, 43 men; mean ± SD age, 68.9 ± 10.1 years) who had undergone 3D-CTA to 1 of 2 protocols; 30 patients underwent scanning under the conventional 120-kilovolt (peak) protocol with filtered back projection (P1); and 30 patients, under an 80-kilovolt (peak) protocol with HIR (P2). The estimated effective radiation dose, computed tomographic attenuation, image noise, contrast-to-noise ratio, and figure of merit were calculated, and the visual image quality of 3D-CTA was scored on a 4-point scale. RESULTS: The mean effective radiation dose was significantly lower under P2 than P1 (4.8 ± 1.2 vs 7.2 ± 1.5 mSv, P < 0.01). P1 and P2 did not significantly differ with respect to the image noise (10.5 ± 2.3 vs 9.9 ± 1.6 Hounsfield units; P = 0.46). Computed tomographic attenuation, contrast-to-noise ratio, figure of merit, and the visual scores for image quality were higher under P2 than P1 (P < 0.01). CONCLUSIONS: The use of low tube voltage and HIR can yield significantly improved image quality at 3D-CTA of the liver.


Assuntos
Angiografia/métodos , Imageamento Tridimensional , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Meios de Contraste , Feminino , Humanos , Iohexol , Iopamidol , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação
9.
Magn Reson Med Sci ; 23(2): 242-248, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36754421

RESUMO

Metamorphosis in the pupae of the Trypoxylus dichotomus was continuously observed at 9.4T until their emergence. A large liquid-like mass occupied most of the volume in the trunk, while the surrounding tissue already existed at the beginning of the observation period. As the mass shrunk, tissues such as flight muscle formed, whereas the reservoir became prolonged to form the intestinal tract. This implies that the liquid-like mass worked as the raw material for creating adult tissues.


Assuntos
Besouros , Animais , Pupa , Besouros/fisiologia , Imageamento por Ressonância Magnética
10.
Naturwissenschaften ; 100(4): 373-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23509009

RESUMO

Male adult butterflies of many species have characteristic odors originating from the disseminating organs known as androconia. Despite the fact that androconia exist in several species, there have been few investigations on adult scents from the lycaenid species. Celastrina argiolus ladonides (Lycaenidae) is a common species in Eurasia. We have reported that male adults of this species emit a faint odor, and the major components causing this odor have been newly found in the Insecta. By using field-caught individuals, we determined the chemical nature and location of this odor in the butterfly. Gas chromatography-mass spectrometry (GC-MS) analyses revealed that two lactone compounds, lavender lactone and δ-decalactone, are present in the extracts of males but absent in those of the females. On an average, approximately 50 ng of each compound was found per male. Chiral GC analyses performed using enantiomerically pure standards revealed that the natural lavender lactone was a mixture of two enantiomers with an R/S ratio of 32:68, whereas the natural δ-decalactone contained only the R-enantiomer. When the analyses were conducted using different parts-forewings, hindwings, and body-of three males, the lactones were more abundantly found on the forewings and hindwings than on the body. Microscopic observation of the wings demonstrated that battledore scales known as androconia are scattered on the upper surface of both the wings of C. argiolus ladonides males. These results indicate that the specialized scales on the wings of males serve as scent-disseminating organs.


Assuntos
Borboletas/química , Lactonas/química , Feromônios/química , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Asas de Animais/química
11.
Naturwissenschaften ; 99(9): 695-703, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22842938

RESUMO

How to acquire sufficient quantity of nitrogen is a pivotal issue for herbivores, particularly for lepidopterans (butterflies and moths) of which diet quality greatly differs among their life stages. Male Lepidoptera often feed from mud puddles, dung, and carrion, a behavior known as puddling, which is thought to be supplementary feeding targeted chiefly at sodium. During copulation, males transfer a spermatophore to females that contains, besides sperm, nutrients (nuptial gifts) rich in sodium, proteins, and amino acids. However, it is still poorly understood how adults, mostly nectarivores, extract nitrogen from the environment. We examined the availability of two ubiquitous inorganic nitrogenous ions in nature, viz. ammonium (or ammonia) and nitrate ions, as nutrients in a butterfly, and show that exogenous ammonia ingested by adult males of the swallowtail, Papilio polytes, can serve as a resource for protein biosynthesis. Feeding experiments with (15)N-labeled ammonium chloride revealed that nitrogen was incorporated into eupyrene spermatozoa, seminal protein, and thoracic muscle. Ammonia uptake by males significantly increased the number of eupyrene sperms in the reproductive tract tissues. The females also had the capacity to assimilate ammonia into egg protein. Consequently, it is evident that acquired ammonia is utilized for the replenishment of proteins allocable for reproduction and somatic maintenance. The active exploitation of exogenous ammonia as a nutrient by a butterfly would foster better understanding of the foraging and reproductive strategies in insects.


Assuntos
Amônia/metabolismo , Borboletas/fisiologia , Biossíntese de Proteínas , Espermatogênese/fisiologia , Amônia/análise , Animais , Borboletas/química , Borboletas/metabolismo , Masculino , Isótopos de Nitrogênio/análise , Isótopos de Nitrogênio/metabolismo , Reprodução/fisiologia , Espermatozoides/química , Espermatozoides/metabolismo
12.
Z Naturforsch C J Biosci ; 67(5-6): 331-41, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22888540

RESUMO

Adults of Papilio protenor demetrius emit a faint odour; the male odour is notably stronger than that of the females. The extracts of whole individuals of each sex comprised 53 compounds regarded as cuticular lipid components, of which the 17 major compounds were straight-chain alkanes and alkenes with 23-31 carbon atoms, higher fatty acids, long-chain aliphatic ketones, squalene, and cholesterol. However, highly volatile compounds were not detected in the whole individual extracts. Eight of the 17 major compounds showed a significant sex difference in relative abundance per individual. Principal component analysis, using the major compounds as variables, revealed a marked sexual dimorphism in the chemical composition of cuticular lipids. From the extracts of 10 dissected individuals of each sex, 21 highly volatile compounds were identified in amounts of less than 200 ng/individual. Among them, linalool and 2,3-butanediol showed a significantly larger amount in males than in females, indicating that the adult odour is also sexually dimorphic. Moreover, both sexes shared several odoriferous compounds, such as heptanal, nonanal, methyl salicylate, benzyl alcohol, and benzoic acid. The faint odour of P. protenor adults, perceivable by the human nose, appears to originate from these volatile compounds.


Assuntos
Borboletas/metabolismo , Lipídeos/análise , Odorantes , Caracteres Sexuais , Animais , Cromatografia Líquida , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Compostos Orgânicos Voláteis/metabolismo
13.
J Chem Ecol ; 37(6): 575-81, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21573758

RESUMO

Papilio maackii females prefer a rutaceous plant, Phellodendron amurense, for oviposition, whereas another semi-sympatric Rutaceae feeder, Papilio protenor, never exploits this plant as a host in nature. However, the larvae of both species perform well on this plant in the laboratory. Phellamurin, a flavonoid present in the organic fraction from P. amurense inhibits egg laying by P. protenor. We examined whether phellamurin is involved in the differential acceptance of P. amurense by the two butterflies. The ovipositing females of P. maackii readily accepted P. amurense and a methanolic extract of the foliage, while P. protenor rejected them entirely. However, the aqueous fraction derived from the extract elicited significant oviposition responses of similar levels from the two species. Phellamurin did not induce oviposition behavior in P. protenor females. In contrast, P. maackii was stimulated to oviposit by phellamurin at concentrations exceeding 0.2%. The response was dose-dependent and reached ca. 70% at 2% phellamurin, which is approximately equivalent to its natural abundance in young leaves of P. amurense. Since the aqueous fraction was very stimulatory to both species, the combined effect of phellamurin and the aqueous fraction on oviposition was tested. The addition of phellamurin to the aqueous fraction enhanced the ovipositional activity of P. maackii, but dramatically suppressed the oviposition response of P. protenor even at 0.1% concentration. These results, taken together with those obtained from electrophysiological recordings with foretarsal chemosensilla, indicate that phellamurin acts as an oviposition stimulant for P. maackii, and as a potent deterrent for P. protenor. The results suggest that host range expansion or host shifts may be made by ovipositing females that overcome phytochemical barriers.


Assuntos
Borboletas/efeitos dos fármacos , Flavonoides/farmacologia , Phellodendron/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Borboletas/fisiologia , Feminino , Flavonoides/isolamento & purificação , Japão , Oviposição , Especificidade da Espécie
14.
Br J Radiol ; 92(1094): 20180215, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30407841

RESUMO

OBJECTIVE:: To evaluate the effects of virtual monochromatic imaging (VMI) using dual-layer spectral detector CT on the image quality of coronary CT angiography (CCTA) acquired by using a low contrast material (CM) dose. METHODS:: We used a VMI 50keV protocol with a 50% CM dose (140 mgI kg-1) to scan 30 patients with renal insufficiency and a 120 kVp with the standard CM dose (280 mgI kg-1) to scan 30 controls without renal insufficiency. Quantitative parameters, including CT attenuation, image noise, and contrast-to-noise ratio (CNR), were measured. The visual image quality factors of contrast enhancement, image noise, beam-hardening artefact, vessel sharpness, and overall image quality were scored on a 4-point scale. RESULTS:: The mean CT attenuation of the ascending aorta was significantly higher for 50 keV VMI than for 120 kVp. Image noise was significantly lower under the 50 keV VMI. CNR and the mean visual score for contrast enhancement were significantly higher for 50 keV VMI. There were no significant differences in the other visual image quality parameters between the two protocols. CONCLUSION:: Dual-layer spectral detector CT using 50 keV VMI enabled reducing the CM dose by 50 % without CCAT image quality degradation in patients with renal insufficiency. ADVANCES IN KNOWLEDGE:: The VMI 50 keV protocol using dual-layer spectral detector CT and a CM dose reduced by 50 % (140 mgI kg-1) can improve the diagnostic image quality of CCTA.


Assuntos
Injúria Renal Aguda/prevenção & controle , Angiografia por Tomografia Computadorizada/instrumentação , Meios de Contraste/administração & dosagem , Processamento de Imagem Assistida por Computador , Iodo/administração & dosagem , Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Injúria Renal Aguda/induzido quimicamente , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/efeitos adversos , Humanos , Iodo/efeitos adversos , Doses de Radiação , Insuficiência Renal
15.
Sci Rep ; 8(1): 5516, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29615771

RESUMO

Certain butterflies utilize plant-acquired alkaloids for their own chemical defense and/or for producing male sex pheromone; a trait known as pharmacophagy. Males of the danaine butterfly, Parantica sita, have been reported to ingest pyrrolizidine alkaloids (PAs) as adults to produce two PA-derived sex pheromone components, viz. danaidone (major) and 7R-hydroxydanaidal. We found, however, that not all PAs that can be precursors for the pheromone serve for mating success of males. Here we show that although the sex pheromone is regarded as a requisite for successful mating, uptake of specific PA(s) (lycopsamine-type PAs) is also imperative for the males to achieve copulation. The increase in the levels of two biogenic amines, octopamine and/or serotonin, in the brain and thoracic ganglia of males fed with specific PA(s) suggested that these alkaloids most likely enhance male mating activity. The results can present new evidence for the evolutionary provenance of pharmacophagous acquisition of PAs in PA-adapted insects.


Assuntos
Borboletas/metabolismo , Copulação , Plantas/metabolismo , Alcaloides de Pirrolizidina/metabolismo , Animais , Transporte Biológico , Borboletas/efeitos dos fármacos , Borboletas/fisiologia , Copulação/efeitos dos fármacos , Masculino , Atrativos Sexuais/biossíntese , Atrativos Sexuais/farmacologia
16.
Phys Med ; 35: 50-58, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28254400

RESUMO

This study compared dosimetric properties among four commercial multi-detector CT (MDCT) scanners. The X-ray beam characteristics were obtained from photon intensity attenuation curves of aluminum and off-center ratio (OCR) profiles in air, which were measured with four commercial MDCT scanners. The absorbed dose for MDCT scanners was evaluated with Farmer ionization chamber measurements at the center and four peripheral points in the body- and head-type cylindrical water phantoms. Measured collected charge was converted to absorbed dose using a 60Co absorbed dose-to-water calibration factor and Monte Carlo (MC)-calculated correction factors. Four MDCT scanners were modeled to correspond with measured X-ray beam characteristics using GMctdospp (IMPS, Germany) software. Al half-value layers (Al-HVLs) with a body-bowtie filter determined from measured Al-attenuation curves ranged 7.2‒9.1mm at 120kVp and 6.1‒8.0mm at 100kVp. MC-calculated Al-HVLs and OCRs in air were in acceptable agreement within 0.5mm and 5% of measured values, respectively. The percentage difference between nominal and actual beam width was greater with decreasing collimation width. The absorbed doses for MDCT scanners at 120kVp ranged 5.1‒7.1mGy and 10.8‒17.5mGy per 100mAs at the center in the body- and head-type water phantoms, respectively. Measured doses at four peripheral points were within 5% agreement of MC-calculated values. The absorbed dose at the center in both water phantoms increased with decreasing Al-HVL for the same charge on the focus. In this study the X-ray beam characteristics and the absorbed dose were measured and compared with calculated values for four MDCT scanners.


Assuntos
Tomógrafos Computadorizados , Tomografia Computadorizada por Raios X/instrumentação , Algoritmos , Calibragem , Radioisótopos de Cobalto , Simulação por Computador , Modelos Teóricos , Método de Monte Carlo , Imagens de Fantasmas , Radiometria , Água , Raios X
17.
Acad Radiol ; 24(3): 295-301, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27913107

RESUMO

RATIONALE AND OBJECTIVES: We compared the effect of iterative model reconstruction (IMR), filtered back projection (FBP), and hybrid iterative reconstruction (HIR) on coronary artery calcium (CAC) scoring. MATERIALS AND METHODS: CAC scans of 30 consecutive patients (18 men and 12 women, age 70.1 ± 12.2 years) were reconstructed with FBP, HIR, and IMR, and the image noise was measured on all images. Two radiologists independently measured the CAC scores using semiautomated software, and interobserver agreement was evaluated. Statistical analysis included the Spearman correlation coefficient and Bland-Altman analysis. RESULTS: The mean image noise on FBP, HIR, and IMR images was 48.0 ± 7.9, 29.6 ± 4.8, and 9.3 ± 1.3 Hounsfield units, respectively. The difference among all reconstruction combinations was significant (P < .01). The CAC score on HIR and IMR scans was 4.2% and 8.9% lower, respectively, than the CAC score on FBP images. There was no significant difference in the mean CAC score among the three reconstructions. The interobserver correlation was excellent for all three reconstructions (r2 = 0.96 FBP, 0.99 HIR, 0.99 IMR); the best Bland-Altman measure of agreement was with IMR, followed by HIR and FBP. CONCLUSION: For CAC scoring, IMR can reduce the image noise and blooming artifacts, and consequently lowers the measured CAC score. IMR can lessen measurement variability and yield stable, reproducible measurements.


Assuntos
Calcinose/diagnóstico por imagem , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Artefatos , Calcinose/complicações , Doença da Artéria Coronariana/complicações , Feminino , Humanos , Masculino , Imagens de Fantasmas , Reprodutibilidade dos Testes
18.
J Insect Physiol ; 52(10): 1043-53, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16979653

RESUMO

Two compounds, 9,10-epoxytetrahydroedulan (ET) and viridiflorine beta-lactone (VL), were identified as major components from the hairpencils of field-caught males of a danaid butterfly, Euploea mulciber. By contrast, laboratory-reared males entirely lacked VL, but possessed a significant quantity of ET. Various feeding experiments with larvae and indoor adult males strongly suggested that ET is biosynthesized de novo only after eclosion from nutrients ingested during the larval development. Since VL was suspected to be derived from pyrrolizidine alkaloids (PAs) acquired as an adult, tests for feeding response to and oral administration of four PAs (a 4:1 mixture of intermedine/lycopsamine, heliotrine, monocrotaline, and retronecine) were conducted. When the tarsi or proboscis were stimulated with PA solutions, males showed positive feeding responses (proboscis extension and sucking movements) to intermedine/lycopsamine, heliotrine, and retronecine in decreasing order of responsiveness, thereby providing evidence that male adults are endowed with taste receptor(s) specific to PAs on the legs as well as on the proboscis. Differently from gustatory responsiveness, only males fed with intermedine/lycopsamine produced a significant quantity of VL (ca. 35 microg/male), whereas those that ingested heliotrine or monocrotaline hydrochloride produced traces of VL (<0.18 microg/male). Uptake of retronecine did not lead to VL formation at all. In behavioral bioassays to test the attractivity of PAs to males, all individuals tested were attracted exclusively to intermedine/lycopsamine. This shows that certain PA(s) per se serve as attractant(s) for males in locating PA sources, and further suggests that in the field, males will seek particular PA(s) that are indispensable as precursors for the efficient biosynthesis of VL.


Assuntos
Comunicação Animal , Comportamento Animal/efeitos dos fármacos , Secreções Corporais/química , Borboletas/química , Comportamento Alimentar/efeitos dos fármacos , Alcaloides de Pirrolizidina/farmacologia , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Japão , Masculino , Monocrotalina/farmacologia , Alcaloides de Pirrolizidina/química
19.
Acad Radiol ; 23(10): 1283-9, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27318785

RESUMO

RATIONALE AND OBJECTIVES: We investigated the effects of small focal spot (SFS) imaging and iterative model reconstruction (IMR) on the image quality of computed tomography angiographs (CTA) in patients with peripheral arterial disease. MATERIALS AND METHODS: We divided 60 consecutive patients with suspected or confirmed peripheral artery disease into two equal groups. One group underwent large focal spot scanning under our standard CTA protocol with hybrid iterative reconstruction (iDose(4)) (protocol 1), and the other underwent scanning with the SFS protocol and IMR (protocol 2). Quantitative image quality parameters, ie, arterial computed tomography attenuation, image noise, and the contrast-to-noise ratio, were compared and the visual image quality (depiction of each vessel) was scored on a 5-point scale. RESULTS: There was no significant difference in the arterial attenuation among all evaluated slice levels. The mean image noise was significantly lower under protocol 2 and the contrast-to-noise ratio was significantly higher at all slice levels. The visual scores assigned to the two protocols for the depiction of large vessels, such as the abdominal aorta and iliac artery, were comparable. However, the mean visual scores for small vessels in the lower extremities were significantly higher under protocol 2. CONCLUSION: CTA with SFS and IMR yielded significantly better qualitative and quantitative image quality especially for small vessels.


Assuntos
Angiografia por Tomografia Computadorizada , Doença Arterial Periférica/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Feminino , Humanos , Masculino , Estudos Prospectivos , Doses de Radiação
20.
J Insect Physiol ; 49(11): 1031-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14568581

RESUMO

Exuded tree sap and rotting fruits are important feeding sources for adults of many butterfly species. However, the chemical composition of such rotting foods and the effects of these constituents on butterfly feeding behaviour have rarely been investigated. Chemical analyses revealed that these food sources contain several major components, including fructose, glucose, ethanol and acetic acid. Moreover, 15 amino acids were identified from the exuded tree sap. The gustatory responsiveness to these components was examined in the proboscis of nymphalid adults of three species (Nymphalis xanthomelas, Kaniska canace and Vanessa indica). The first two species primarily feed on sap and rotting fruits, while V. indica frequently visits flowers. Fructose elicited larger feeding responses from these saprophagous butterflies than glucose, which had a feeding-stimulatory effect only on N. xanthomelas at a concentration equivalent to that of the food. Ethanol, acetic acid and the five major amino acids identified in tree sap did not elicit feeding responses by themselves. However, ethanol and/or acetic acid, when mixed with these sugars at equivalent concentrations, evoked feeding and enhanced probing responses in K. canace and V. indica. These results suggest that ethanol and acetic acid, together with sugars at low concentrations, synergistically stimulate butterfly feeding behaviour.


Assuntos
Ácido Acético/farmacologia , Borboletas/fisiologia , Etanol/farmacologia , Comportamento Alimentar , Frutose/farmacologia , Frutas/química , Glucose/farmacologia , Árvores , Animais , Bioensaio , Sinergismo Farmacológico , Fermentação
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