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1.
PLoS One ; 18(3): e0282351, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36947508

RESUMO

Wood is difficult for most animals to digest due to large amounts of indigestible polymers, but some wood-feeding insects are considered to be able to utilize it as food with the aid of microbial symbionts. Most members of flower longicorn beetles (Coleoptera: Cerambycidae: Lepturinae) feed on nectar and pollen of flowers as adults and wood as larvae. In some lepturines, associations with yeasts are known: female adults possess fungus-storing organs (termed mycetangia) at ovipositors, and larvae also possess such organs (termed mycetomes) in their midguts to carry the associated yeasts. Despite the high diversity of Lepturinae in the world, lepturine-yeast associations, such as the consistency of associated yeasts among the beetle's developmental stages and ecological function of yeast symbionts, have been poorly documented. Here, we investigated the yeast symbiont of the Japanese common lepturine Leptura ochraceofasciata. X-ray computed microtomography revealed that a pair of tube-like, S-shaped mycetangia was located at the basal part of the ovipositor and that a muscle bundle joined the apex of the mycetangium to spiculum ventrale of sternum VIII. All female adults harbored only one yeast species, Scheffersomyces insectosa, in the mycetangia. All larvae harbored S. insectosa exclusively in the mycetomes. Scheffersomyces insectosa was also recovered from surfaces of eggs. Scheffersomyces insectosa assimilated wood-associated sugars including xylose, cellobiose, and xylan in culture. These results suggest the intimate association between L. ochraceofasciata and S. insectosa: S. insectosa is transmitted from the mother to offspring during oviposition and may be related to larval growth in wood.


Assuntos
Besouros , Feminino , Animais , Simbiose , Leveduras/fisiologia , Larva , Flores
2.
Sci Rep ; 12(1): 11243, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35788621

RESUMO

Understanding the actual situation of radiocesium (137Cs) contamination of trees caused by the Fukushima nuclear accident is essential for predicting the future contamination of wood. Particularly important is determining whether the 137Cs dynamics within forests and trees have reached apparent steady state. We conducted a monitoring survey of four major tree species (Japanese cedar, Japanese cypress, konara oak, and Japanese red pine) at multiple sites. Using a dynamic linear model, we analyzed the temporal trends in 137Cs activity concentrations in the bark (whole), outer bark, inner bark, wood (whole), sapwood, and heartwood during the 2011-2020 period. The activity concentrations were decay-corrected to September 1, 2020, to exclude the decrease due to the radioactive decay. The 137Cs concentrations in the whole and outer bark samples showed an exponential decrease in most plots but a flat trend in one plot, where 137Cs root uptake is considered to be high. The 137Cs concentration ratio (CR) of inner bark/sapwood showed a flat trend but the CR of heartwood/sapwood increased in many plots, indicating that the 137Cs dynamics reached apparent steady state within one year in the biologically active parts (inner bark and sapwood) and after several to more than 10 years in the inactive part (heartwood). The 137Cs concentration in the whole wood showed an increasing trend in six plots. In four of these plots, the increasing trend shifted to a flat or decreasing trend. Overall, the results show that the 137Cs dynamics within forests and trees have reached apparent steady state in many plots, although the amount of 137Cs root uptake in some plots is possibly still increasing 10 years after the accident. Clarifying the mechanisms and key factors determining the amount of 137Cs root uptake will be crucial for predicting wood contamination.


Assuntos
Acidente Nuclear de Fukushima , Radioisótopos de Césio , Casca de Planta , Árvores , Madeira
3.
Curr Microbiol ; 78(8): 3212-3217, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34215937

RESUMO

Lignin-decomposing ability of several bacteria and the degradation mechanism have been revealed in vitro. However, the abundance of such bacteria in decayed wood in nature remains unknown at genus and species levels. This study was aimed at identifying bacterial communities in the decayed wood coexisting with white-rot fungi, which play a potential role in lignin degradation, and predicting the functional profile of bacterial lignin degradation in wood via bacterial community analyses. The bacterial flora of forest soil and four decayed wood samples showed marked differences; particularly, in addition to Methylobacterium and Acidibrevibacterium, sphingomonads, which degrade the major skeleton of lignin in vitro, were more abundant in the decayed wood than in forest soil, suggesting that multiple bacteria were involved in lignin degradation. The bacterial community in the decayed wood was more influenced by wood type and lignin structure than the fungal species observed in the decayed wood.


Assuntos
Basidiomycota , Madeira , Bactérias/genética , Basidiomycota/genética , Fungos/genética , Lignina
4.
Rev Sci Instrum ; 90(7): 076104, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31370456

RESUMO

We developed an accurate and precise system for controlling dew points by using an active pressure control system in a primary standard humidity generator. By using this system, an adjustment capability to a target value of 0.0008 °C was attained for dew-point generation, compared with the previous value of approximately 0.01 °C. In a two-pressure humidity generator, the drift in the dew point with time owing to a rapid drop in the water level in the presaturator and to fluctuations in atmospheric pressure was greatly suppressed. The standard deviation of the dew point obtained with our dew-point control system was 10 times smaller than the drift observed in the absence of the system. This dew-point control system makes it possible to calibrate humidity sensors at target values with greater efficiency.

5.
J Environ Radioact ; 178-179: 335-342, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28965024

RESUMO

To understand the changes in radiocesium (137Cs) concentrations in stem woods after the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, we investigated 137Cs concentrations in the bark, sapwood, heartwood, and whole wood of four major tree species at multiple sites with different levels of radiocesium deposition from the FDNPP accident since 2011 (since 2012 at some sites): Japanese cedar at four sites, hinoki cypress and Japanese konara oak at two sites, and Japanese red pine at one site. Our previous report on 137Cs concentrations in bark and whole wood samples collected from 2011 to 2015 suggested that temporal variations were different among sites even within the same species. In the present study, we provided data on bark and whole wood samples in 2016 and separately measured 137Cs concentrations in sapwood and heartwood samples from 2011 to 2016; we further discussed temporal trends in 137Cs concentrations in each part of tree stems, particularly those in 137Cs distributions between sapwood and heartwood, in relation to their species and site dependencies. Temporal trends in bark and whole wood samples collected from 2011 to 2016 were consistent with those reported in samples collected from 2011 to 2015. Temporal variations in 137Cs concentrations in barks showed either a decreasing trend or no clear trend, implying that 137Cs deposition in barks is inhomogeneous and that decontamination is relatively slow in some cases. Temporal trends in 137Cs concentrations in sapwood, heartwood, and whole wood were different among species and also among sites within the same species. Relatively common trends within the same species, which were increasing, were observed in cedar heartwood, and in oak sapwood and whole wood. On the other hand, the ratio of 137Cs concentration in heartwood to that in sapwood (fresh weight basis) was commonly increased to more than 2 in cedar, although distinct temporal trends were not found in the other species, for which the ratio was around 1 in cypress and pine and below 0.5 in oak, suggesting that 137Cs transfer from sapwood to heartwood shows species dependency. Consequently, the species dependency of 137Cs transfer within the tree appears easily, while that from the environment to the trees can be masked by various factors. Thus, prediction of 137Cs concentrations in stem wood should be carried out carefully as it still requires investigations at multiple sites with a larger sample size and an understanding of the species-specific 137Cs transfer mechanism.


Assuntos
Radioisótopos de Césio/análise , Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos/análise , Árvores/química , Chamaecyparis , Cryptomeria , Florestas , Madeira/química
6.
Rev Sci Instrum ; 86(10): 106110, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26521007

RESUMO

We report a simple, robust cavity ring-down spectroscopy system to reliably measure trace moisture in gases at parts-per-trillion (ppt) levels. The performance of the system was evaluated on the basis of experiments performed in a manner traceable to the International System of Units. The obtained result was in good agreement with the primary trace-moisture standard at 12 nmol/mol (12 ppb) in N2 in amount-of-substance fraction. Measurement capability of residual moisture in high-purity dry N2 at ∼130 pmol/mol (130 ppt) was demonstrated, and background noise of 5.3 × 10(-12) cm(-1) was attained, corresponding to a minimum detectable H2O of 5 pmol/mol (5 ppt).

7.
Planta ; 242(3): 613-29, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26105650

RESUMO

MAIN CONCLUSION: Phloem production and structural development were interlinked with seasonal variation in the primary and secondary metabolites of phloem. Novel microtechniques provided new perspectives on understanding phloem structure and chemistry. To gain new insights into phloem formation in Norway spruce (Picea abies), we monitored phloem cell production and seasonal variation in the primary and secondary metabolites of inner bark (non-structural carbohydrates and phenolic stilbene glucosides) during the 2012 growing season in southern and northern Finland. The structure of developing phloem was visualised in 3D by synchrotron X-ray microtomography. The chemical features of developing phloem tissues isolated by laser microdissection were analysed by chemical microanalysis. Within-year phloem formation was associated with seasonal changes in non-structural carbohydrates and phenolic extractive contents of inner bark. The onset of phloem cell production occurred in early and mid-May in southern and northern Finland, respectively. The maximal rate of phloem production and formation of a tangential band of axial phloem parenchyma occurred in mid-June, when total non-structural carbohydrates peaked (due to the high amount of starch). In contrast, soluble sugar content dropped during the most active growth period and increased in late summer and winter. The 3D visualisation showed that the new axial parenchyma clearly enlarged from June to August. Sub-cellular changes appeared to be associated with accumulation of stilbene glucosides and soluble sugars in the newest phloem. Stilbene glucosides also increased in inner bark during late summer and winter. Our findings may indicate that stilbene biosynthesis in older phloem predominantly occurs after the formation of the new band(s) of axial parenchyma. The complementary use of novel microtechniques provides new perspectives on the formation, structure, and chemistry of phloem.


Assuntos
Floema/crescimento & desenvolvimento , Floema/metabolismo , Picea/crescimento & desenvolvimento , Picea/metabolismo , Casca de Planta/crescimento & desenvolvimento , Casca de Planta/metabolismo , Estações do Ano
8.
Tree Physiol ; 34(8): 856-68, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24633653

RESUMO

To investigate the biological mechanism by which trees control the changes in microfibril (MF) orientation among secondary cell wall layers of conifer tracheids, we studied seasonal variation in the orientation of newly deposited MFs during tracheid cell wall development in Japanese cedar (Cryptomeria japonica D. Don) trees growing in Central Japan (36°36'N, 140°39'E). Sample blocks were repeatedly collected from four 16-year-old clones of different origins during the growing season of 2010 to investigate the hypotheses that changes in cellulose MF orientation between wall layers exhibited seasonal and clonal differences. The progressive change in the orientation of newly deposited MFs on the primary and secondary cell wall layers of tracheids was detected by field-emission-scanning electron microscopy. Tracheid production and differentiation was studied by light microscopy. We observed a decreasing trend in the orientation of deposited MFs from earlywood to latewood in the S2 and S1 layers, where MFs appeared in a Z-helix. In contrast, no seasonal pattern in the orientation of the MFs in the S-helix was observed. Minor clonal variation was observed in the phenology of tracheid production and differentiation. We concluded that a seasonal decreasing trend in the orientation of the MFs in the Z-helix in S1 and S2 was present, whereas the MFs in other layers exhibited minor random variations. Thus, the orientation of the MFs in S2 was affected by seasonal factors, whereas the MFs in other layers were more intrinsically controlled. The within-ring variations in the MF orientation and thus the resulting average MF angle might also be related to genotypic differences in the tracheid production and differentiation rate. However, our results do not exclude other intrinsic and environmental regulations in the change in MF orientation, which remains a topic for future studies.


Assuntos
Parede Celular , Celulose/metabolismo , Cryptomeria/fisiologia , Genótipo , Microfibrilas/metabolismo , Estações do Ano , Xilema/crescimento & desenvolvimento , Cryptomeria/genética , Japão , Árvores/fisiologia , Madeira/crescimento & desenvolvimento , Xilema/citologia
9.
Pancreas ; 42(6): 1027-33, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23851436

RESUMO

OBJECTIVES: Pancreatic cancer is one of the most lethal malignancies; its poor prognosis is strongly associated with invasion and metastasis. Expression of S100A4 has been reported to correlate with poor prognosis in various cancers. We have investigated the role of S100A4 in pancreatic cancer tumorigenesis and its clinicopathologic significance. METHODS: Protein expression of S100A4 was examined by Western blot in pancreatic cancer cell lines and a human pancreatic ductal epithelium cell line, HPDE-6. Then the expressions of S100A4, TP53, and CD133 were examined immunohistochemically in resected specimens from 83 patients with pancreatic cancer to clarify their clinicopathologic significance. Survival analyses were performed using the Kaplan-Meier method and the Mantel-Cox method. RESULTS: Forty-eight (58%) of 83 patients with pancreatic cancer positively expressed S100A4, and 50 (60%) and 29 (36%) patients positively expressed TP53 and CD133, respectively. S100A4 expression was significantly correlated with perineural invasion (P = 0.029) and invasion pattern (P = 0.001). Neither TP53 nor CD133 expression showed significant correlations with any other parameters. CONCLUSIONS: Our present results suggest that S100A4 plays an important role in the invasiveness, particularly with perineural invasion and invasion pattern, of pancreatic cancer. Development of new strategies targeting S100A4 or its downstream effectors is warranted.


Assuntos
Adenocarcinoma/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteínas S100/biossíntese , Antígeno AC133 , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/metabolismo , Western Blotting , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Glicoproteínas/metabolismo , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Pancreáticas/patologia , Peptídeos/metabolismo , Prognóstico , Proteína A4 de Ligação a Cálcio da Família S100 , Análise Serial de Tecidos , Proteína Supressora de Tumor p53/metabolismo
10.
J Plant Res ; 124(1): 35-48, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20473629

RESUMO

The extent of tropical forest has been declining, due to over-exploitation and illegal logging activities. Large quantities of unlawfully extracted timber and other wood products have been exported, mainly to developed countries. As part of the export monitoring effort, we have developed methods for extracting and analyzing DNA from wood products, such as veneers and sawn timbers made from dipterocarps, in order to identify the species from which they originated. We have also developed a chloroplast DNA database for classifying Shorea species, which are both ecologically and commercially important canopy tree species in the forests of Southeast Asia. We are able to determine the candidate species of wood samples, based on DNA sequences and anatomical data. The methods for analyzing DNA from dipterocarp wood products may have strong deterrent effects on international trade of illegitimate dipterocarp products. However, the method for analyzing DNA from wood is not perfect for all wood products and need for more improvement, especially for plywood sample. Consequently, there may be benefits for the conservation of tropical forests in Southeast Asia.


Assuntos
Bases de Dados de Ácidos Nucleicos , Dipterocarpaceae/classificação , Dipterocarpaceae/genética , Análise de Sequência de DNA/métodos , Madeira/genética , Sequência de Bases , Ácidos Graxos Insaturados/genética , Variação Genética , Dados de Sequência Molecular , Nucleotídeos/genética , Filogenia , Especificidade da Espécie , Madeira/anatomia & histologia
11.
AJR Am J Roentgenol ; 195(4): 882-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20858813

RESUMO

OBJECTIVE: The aim of this study was to compare the accuracy, sensitivity, and positive predictive value of C-arm CT with those of MDCT in the detection of hepatocellular carcinoma. MATERIALS AND METHODS: We retrospectively evaluated the cases of 50 patients with nodules of hepatocellular carcinoma who underwent biphasic MDCT and selective C-arm CT with flat-detector angiographic systems. We evaluated arterial phase C-arm CT images and the corresponding biphasic MDCT images of 59 hepatic areas in 50 patients. Three independent blinded observers rated both sets of images using a detection confidence scale. The diagnostic accuracy of the two techniques was compared on the basis of area under alternative free-response receiver operating characteristic curve (A(1)). Focal accumulation of iodized oil was the reference standard. RESULTS: Accuracy was significantly higher for C-arm CT (A(1) = 0.830) than for MDCT (A(1)= 0.618) for lesions smaller than 10 mm in diameter (p < 0.001), but the accuracy of the two techniques did not differ significantly for lesions measuring 10 mm or larger. C-arm CT was significantly more sensitive than MDCT in the detection of lesions 20 mm or smaller (74.1% vs 34.0% for lesions < 10 mm [p < 0.001]; 94.7% vs 77.1% for lesions 10-20 mm [p < 0.001]). The positive predictive values of the two techniques did not differ significantly irrespective of lesion size. CONCLUSION: Compared with biphasic MDCT, C-arm CT depicted hepatocellular carcinoma lesions smaller than 10 mm with more accuracy and those 20 mm and smaller with more sensitivity. The two techniques were equally accurate in the detection of hepatocellular carcinoma lesions 10 mm in diameter and larger.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Angiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
12.
Jpn J Radiol ; 28(3): 227-30, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20437135

RESUMO

An 86-year-old man with dysphagia underwent gastrointestinal fiberscopy (GIF) and was found to have a circumferential type 3 advanced carcinoma in the upper thoracic esophagus and a type 2 tumor in the posterior wall of the gastric body. Microscopic examination of biopsy specimens of both tumors demonstrated moderately differentiated squamous cell carcinoma. He was diagnosed as having stage IVb (T3N0M1b) esophageal carcinoma with gastric wall metastasis. A total of 60 Gy in 30 fractions of three-dimensional conformal radiation therapy (3D-CRT) was first administered to the esophageal carcinoma, next to the gastric wall metastasis. Concurrent chemotherapy was not given because of the patient's refusal. No subjective morbidity was observed during the treatment. In the GIF study immediately after 3D-CRT, both esophageal and gastric wall tumors had attained a complete response. The dysphagia dissolved as the esophageal tumor shrunk. The patient has been doing well for 17 months after the start of 3D-CRT. No local recurrence was observed in either the esophagus or the stomach during follow-up GIF. Considering the dismal prognosis of esophageal carcinoma patients with intramural metastasis to the stomach, a watchful follow-up is needed.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/secundário , Neoplasias Esofágicas/patologia , Neoplasias Gástricas/radioterapia , Neoplasias Gástricas/secundário , Idoso de 80 Anos ou mais , Humanos , Masculino , Neoplasias Primárias Múltiplas , Dosagem Radioterapêutica , Radioterapia Conformacional , Neoplasias Retais/cirurgia
13.
Indian J Radiol Imaging ; 20(1): 39-41, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20351991

RESUMO

During retrograde transvenous sclerotherapy for gastric varices, sufficient opacification of the target varices on venography is essential for successful treatment. However, venography sometimes cannot identify target varices due to overlapping adjacent collateral vessels or leakage of contrast medium to other outflow veins. We report how C-arm CT images acquired using a flat-panel detector angiography system helped to identify target varices and predict the distribution of a sclerosant, which resulted in safer sclerotherapy and increased operator confidence.

15.
Mycologia ; 102(1): 11-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20120223

RESUMO

We examined the species richness and host utilization patterns of wood-inhabiting aphyllophoraceous fungi (polypores and related fungi) in an old-growth beech and oak forest in a cool, temperate area of Japan. Coarse woody debris (CWD) > or = 20 cm diam within a 6 ha plot was surveyed in Sep 2002. Tree genus, diameter, decay class and tree part of CWD samples were recorded. Fruiting bodies of aphyllophoraceous fungi that arose from the CWD were surveyed three times and identified to species. In total 256 CWD samples from 12 tree genera were surveyed with Quercus being the most frequent followed by Castanea and Fagus. From 196 CWD samples we recorded 436 wood-inhabiting fungi belonging to 63 species. Fifteen fungal species had at least 10 records, with Hymenochaete rubiginosa, Daedalea dickinsii, Xylobolus frustulatus, Rigidoporus cinereus and the small form of Fomes fomentarius being the most frequent. The number of fungal species that appeared on Fagus was significantly larger than that on Castanea, when the number of fruiting bodies collected was at least 50. The occurrences of the 15 dominant fungal species, except Trametes versicolor, were related to traits of the CWD. Tree genus was a predictor variable that affected the appearance of 11 of the 15 species of wood-inhabiting fungi. Only the tree part was selected for the models of Rigidoporus eminens, Schizopora flavipora and Stereum ostrea. Our results suggest that tree genus and tree part are important factors determining fungal community structure because these were selected as complementary predictor variables. Both oak and beech appear to be the most important tree genera for maintaining wood-inhabiting fungal species richness because the fungal flora formed on oak CWD is nearly complementary to those on chestnut, with low fungal species richness.


Assuntos
Basidiomycota/crescimento & desenvolvimento , Fagaceae/microbiologia , Fagus/microbiologia , Quercus/microbiologia , Basidiomycota/classificação , Clima , Conservação dos Recursos Naturais , Ecossistema , Japão , Especificidade da Espécie , Temperatura , Árvores , Madeira
16.
Ann Bot ; 103(7): 1145-57, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19258338

RESUMO

BACKGROUND AND AIMS: Although the lateral movement of water and gas in tree stems is an important issue for understanding tree physiology, as well as for the development of wood preservation technologies, little is known about the vascular pathways for radial flow. The aim of the current study was to understand the occurrence and the structure of anatomical features of sugi (Cryptomeria japonica) wood including the tracheid networks, and area fractions of intertracheary pits, tangential walls of ray cells and radial intercellular spaces that may be related to the radial permeability (conductivity) of the xylem. METHODS: Wood structure was investigated by light microscopy and scanning electron microscopy of traditional wood anatomical preparations and by a new method of exposed tangential faces of growth-ring boundaries. KEY RESULTS: Radial wall pitting and radial grain in earlywood and tangential wall pitting in latewood provide a direct connection between subsequent tangential layers of tracheids. Bordered pit pairs occur frequently between earlywood and latewood tracheids on both sides of a growth-ring boundary. In the tangential face of the xylem at the interface with the cambium, the area fraction of intertracheary pit membranes is similar to that of rays (2.8 % and 2.9 %, respectively). The intercellular spaces of rays are continuous across growth-ring boundaries. In the samples, the mean cross-sectional area of individual radial intercellular spaces was 1.2 microm(2) and their total volume was 0.06 % of that of the xylem and 2.07 % of the volume of rays. CONCLUSIONS: A tracheid network can provide lateral apoplastic transport of substances in the secondary xylem of sugi. The intertracheid pits in growth-ring boundaries can be considered an important pathway, distinct from that of the rays, for transport of water across growth rings and from xylem to cambium.


Assuntos
Cryptomeria/anatomia & histologia , Cryptomeria/crescimento & desenvolvimento , Xilema/anatomia & histologia , Xilema/crescimento & desenvolvimento
17.
AJR Am J Roentgenol ; 192(4): 1057-63, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19304714

RESUMO

OBJECTIVE: This study compares the diagnostic accuracy of C-arm CT with digital subtraction angiography (DSA) in identifying tumor-feeding arteries during superselective transarterial chemoembolization (TACE). MATERIALS AND METHODS: Thirty-three consecutive patients with hepatocellular carcinoma (HCC) underwent superselective TACE using a flat-detector angiographic system. Angiographic operators determined which feeding arteries were potentially supplying the target tumor. When two or more feeding arteries were possible, all were included. Superselective DSA and C-arm CT were sequentially performed for each studied artery. Four independent observers separately viewed the DSA and C-arm CT images and used a 5-point grading scale to determine whether a studied artery supplied the target tumor. Diagnostic performance was compared using receiver operating characteristic (ROC) analysis. Sensitivity, specificity, and accuracy were calculated for arteries rated as definite or probable tumor feeders. Iodized oil accumulation on follow-up CT was the reference standard. RESULTS: We examined 58 possible feeding arteries in 33 patients. Among the studied arteries, follow-up CT confirmed that 33 were verified tumor-feeding arteries, and the remaining 25 were not. C-arm CT resulted in a significantly larger area under the ROC curve (A(z) = 0.995) compared with DSA (A(z) = 0.841). The sensitivity, specificity, and accuracy of C-arm CT (96.9%, 97.0%, and 96.9%, respectively) were significantly higher than those for DSA (77.2%, 73.0%, and 75.4%). CONCLUSION: C-arm CT is superior to DSA for identifying tumor-feeding arteries during superselective TACE for HCC.


Assuntos
Angiografia Digital/métodos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Fígado/irrigação sanguínea , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Interpretação de Imagem Radiográfica Assistida por Computador , Sensibilidade e Especificidade
18.
J Clin Oncol ; 27(11): 1806-13, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19273710

RESUMO

PURPOSE: Contrary to the extensive data accumulated regarding pancreatic carcinogenesis, the clinical and molecular features characteristic of advanced stage (stage III and IV) disease are unknown. A comprehensive study of pancreatic cancers from patients who have succumbed to their disease has the potential to greatly expand our understanding of the most lethal stage of this disease and identify novel areas for intervention. MATERIALS AND METHODS: Rapid autopsies were performed on 76 patients with documented pancreatic cancer. The histologic features of end stage disease were determined and correlated to the stage at initial diagnosis, patterns of failure (locally destructive v metastatic disease) and the status of the KRAS2, TP53, and DPC4 genes. RESULTS: At autopsy, 30% of patients died with locally destructive pancreatic cancer, and 70% died with widespread metastatic disease. These divergent patterns of failure found at autopsy (locally destructive v metastatic) were unrelated to clinical stage at initial presentation, treatment history, or histopathologic features. However, Dpc4 immunolabeling status of carcinoma tissues harvested at autopsy, a sensitive marker of DPC4 genetic status, was highly correlated with the presence of widespread metastasis but not with locally destructive tumors (P = .007). CONCLUSION: Pancreatic cancers are represented by distinct genetic subtypes with significantly different patterns of failure. Determinations of DPC4 status at initial diagnosis may be of value in stratifying patients into treatment regimens related to local control versus systemic therapy.


Assuntos
Adenocarcinoma/genética , Carcinoma Adenoescamoso/genética , Neoplasias Pancreáticas/genética , Proteína Smad4/genética , Adenocarcinoma/patologia , Idoso , Autopsia , Carcinoma Adenoescamoso/patologia , Feminino , Genes p53/genética , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Valor Preditivo dos Testes , Prognóstico , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Análise de Sobrevida , Falha de Tratamento , Proteínas ras/genética
19.
Am J Bot ; 96(8): 1399-408, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21628287

RESUMO

The morphological variation and structure-function relationships of xylem parenchyma still remain open to discussion. We analyzed the three-dimensional structure of a poorly known type of xylem parenchyma with disjunctive walls in the tropical hardwood Okoubaka aubrevillei (Santalaceae). Disjunctive cells occurred among the apotracheal parenchyma cells and at connections between axial and ray parenchyma cells. The disjunctive cells were partly detached one from another, but their tubular structures connected them into a continuous network of axial and ray parenchyma. The connecting tubules had thick secondary walls and simple pits with plasmodesmata at the points where one cell contacted a tubule of another cell. The imperforate tracheary elements of the ground tissue were seven times longer than the axial parenchyma strands, a fact that supports a hypothesis that parenchyma cells develop disjunctive walls because they are pulled apart and partly separated during the intrusive growth of fibers. We discuss unresolved details of the formation of disjunctive cell walls and the possible biomechanical advantage of the wood with disjunctive parenchyma: the proportion of tissue that improves mechanical strength is increased by the intrusive elongation of fibers (thick-walled tracheids), whereas the symplastic continuum of the parenchyma is maintained through formation of disjunctive cells.

20.
Planta ; 227(6): 1187-97, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18214528

RESUMO

A unique fiber spinning was found in protoplasts from white birch (Betula platyphylla) leaves under an acidic medium containing high concentration of Ca(2+). After expanding from 10 to 100 microm in diameter under the culture condition, the protoplast started secreting a gigantic fiber while moving in a spiral way. Real time video analyses elucidated that the orientation, rate and pattern of the motion were directed due to the inverse force of the fiber spinning. Moreover, observation using several microscopic methods accompanied with histochemical staining and nuclear magnetic resonance (NMR) analysis indicated that the fiber was composed of 400-500 nm wide (1-->3)-beta-glucan hollow sub-fibrils. This entire phenomenon may be a response against the stress imposed. The observation presented provides an understanding of the unique relationship between fiber spinning and the bottom-up fiber fabrication from nano to micro scales.


Assuntos
Betula/citologia , Protoplastos/citologia , Cinética , Espectroscopia de Ressonância Magnética , Microscopia de Força Atômica , Movimento , Protoplastos/ultraestrutura , Árvores , Gravação em Vídeo
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