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141.
Analysis of natural host-parasite relationships reveals the evolutionary forces that shape the delicate and unique specificity characteristic of such interactions. The accessory long gland-reservoir complex of the wasp Leptopilina heterotoma (Figitidae) produces venom with virus-like particles. Upon delivery, venom components delay host larval development and completely block host immune responses. The host range of this Drosophila endoparasitoid notably includes the highly-studied model organism, Drosophila melanogaster. Categorization of 827 unigenes, using similarity as an indicator of putative homology, reveals that approximately 25% are novel or classified as hypothetical proteins. Most of the remaining unigenes are related to processes involved in signaling, cell cycle, and cell physiology including detoxification, protein biogenesis, and hormone production. Analysis of L. heterotoma's predicted venom gland proteins demonstrates conservation among endo- and ectoparasitoids within the Apocrita (e.g., this wasp and the jewel wasp Nasonia vitripennis) and stinging aculeates (e.g., the honey bee and ants). Enzyme and KEGG pathway profiling predicts that kinases, esterases, and hydrolases may contribute to venom activity in this unique wasp. To our knowledge, this investigation is among the first functional genomic studies for a natural parasitic wasp of Drosophila. Our findings will help explain how L. heterotoma shuts down its hosts' immunity and shed light on the molecular basis of a natural arms race between these insects.  相似文献   
142.
In the management of patients with differentiated thyroid cancer (DTC), abnormalities detected on planar whole body scan and 131I-SPECT are difficult to interpret because of a lack of anatomical landmarks and limited specificity. Integrated 131I-SPECT-CT imaging has an additional value for characterization of equivocal tracer uptake seen on planar imaging as well as for precise localization. We illustrate through an observation the incremental diagnostic value of 131I-SPECT-CT images in the diagnosis of a cervical lymph node mimicking a physiological uptake on planar views. A 35-year-old Tunisian female was followed for papillary thyroid carcinoma, for which she underwent total thyroidectomy and iratherapy. Three years after a complete remission, the thyroglobulin (Tg) level on TSH stimulation increased. Diagnostic planar images with 131I did not disclose any obvious pathological foci. Furthermore, we noticed an increased 131I-uptake in the left sub-mandibulary area, which suggested a salivary physiological activity. SPECT-CT of the neck and chest were then performed with a Symbia T camera. Fused images demonstrate that this activity corresponds to a cervical lymph node closely adjacent to sub-mandibulary gland. Management of the patient was then changed. In selected patients with DTC, hybrid imaging should be used as a complementary to planar imaging in terms of diagnostic accuracy, because of superior focus localization and additional anatomic information derived from the CT component. Integrated SPECT-CT is then a useful tool, especially in cases of unclear diagnoses, precising anatomical localization of areas of increased 131I-uptake and distinguishing malignant lesions from normal physiological uptakes. This is particularly important in an oncologic center, as ours, where we don’t yet have a positron emission tomography (PET) camera is not yet available.  相似文献   
143.

Aim

To report and discuss an unusual visceral uptake on bone scan in a case of breast cancer with bone metastases.

Patient and methods

A 40-year-old woman, with untreated bilateral breast cancer was referred to our department for a bone scan.

Results

The bone scan evidenced multiple metastases over the axial skeleton. Uncommonly, visceral uptake was noted associating diffuse bilateral lung uptake and intense myocardium, stomach and kidneys uptakes. Serum calcium level was high: 4.08 mmol/L (normal: 2.38–2.70 mmol/L).

Conclusion

The incidental observation of metastasic calcifications on bone scan is often related to severe hypercalcemia. Such pattern should alert the physician on the existence and the severity of calcium metabolism disturbances that had not been suggested before.  相似文献   
144.
Three turtle shells from the Middle Jurassic Xintiangou Formation of Yunyang (Chongqing, China) are described and assigned to Xinjiangchelyidae (Testudines: Eucryptodira). This is the first report of turtle remains from the Xintiangou Formation, Sichuan Basin and represents the oldest known Xinjiangchelyidae. The assemblage includes two taxa, Protoxinjiangchelys sp. and Xinjiangchelyidae indet. This discovery extends the stratigraphical distribution of Xinjiangchelyidae and improves our knowledge about the early evolution of that family. It demonstrates that by the Middle Jurassic, at the time of deposition of the Xintiangou Formation, the group was already diversified in the Sichuan Basin.  相似文献   
145.
《Médecine Nucléaire》2020,44(3):181-188
18F-FDG PET is recommended for the initial staging of locally advanced breast cancer. Studies have shown the prognostic value of 18F-FDG PET for staging, but its ability to predict pathological complete response remains uncertain. Our objective was to determine the predictive value of early therapeutic evaluation by 18F-FDG PET for HER2-positive breast cancer patients. We studied a subpopulation of the prospective and multicentric French NeoTOP trial, at interim analysis. All patients were eligible for neoadjuvant chemotherapy. A 18F-FDG PET was performed at baseline and then after one cycle of neoadjuvant treatment. 18F-FDG PET were studied by three conventional methods (two visuals and one quantitative) and by textural analysis. Complete pathological response on surgical samples corresponded to grades 1/2 of Chevallier's classification and no responders corresponded to grades 3/4 of Chevallier. Pathological results were available for 21 patients. SUVmax decreased by 55% after one cycle of chemotherapy. No difference between groups was found with visuals, conventional quantitative and textural analysis of tumour uptake evaluations. Early therapeutic evaluation by 18F-FDG PET for HER2-positive breast cancer was not predictive of pathological therapeutic response after neoadjuvant treatment, with conventional study or textural analyses in this interim analysis.  相似文献   
146.
A L Koch 《Biochimie》1985,67(1):137-140
The membrane transport systems for galactosides and glucose derivatives interact in enteric microorganisms. Stop-flow experiments with a double wavelength spectrophotometer and a flow-through cuvette (designed to minimize light-scattering effects) were used to measure the speed of interaction in Escherichia coli. The in vivo hydrolysis of ortho-nitrophenol-beta-D-galactopyranoside was measured by comparing the light transmitted by cell suspensions at 420 nm with that at 500 nm. Measurements at the latter wavelength corrected for residual scattering effects. The stop-flow experiment allowed the study of the early kinetics of transport and hydrolysis. It was found with strain ML308 that there was a significant lag in the achievement of steady-state inhibition by glucose and its derivative methyl-alpha-D-glucopyranoside (alpha MG). This strain constitutively produces high levels of permease and beta-galactosidase. The absorbancy increases at 420 nm are limited by transport because the beta-galactosidase is present inside the cells in excess. From earlier results, it was not surprising that inhibition is delayed with low concentrations of the glucose compounds, but the new double wavelength technique showed no kinetic component of rapid inhibition. This result therefore excludes competition for some membrane-bound component and is consistent with the production of the dephosphorylated form of the soluble Enzyme IIIglu that binds and inhibits the permease system in the membrane.  相似文献   
147.
Recent definition of the Cantabrian Lower Azilian has turned the Late Upper Magdalenian/Azilian transition into one of the most interesting archaeological ages in the area. This period is considered representing the earliest Azilian groups in Asturias. Critic review of Cueva Oscura de Ania record, in the center of Asturias, has allowed us to give full details of the Lower Azilian archaeological characteristics. Cueva Oscura de Ania archaeological collection shows archaic traits, close to those from Cueva de Los Azules and Cueva de La Riera, two eastern asturian sites. These likenesses suggest a high stylistic and technical uniformity in distant areas during a critical period, when Palaeolithic groups changed their subsistence strategies. Cueva Oscura de Ania archaeological and polinic records suggest that this deposit was built at the beginning of the paleoclimatic phase known as Alleröd/Cantabrian VIII (12 000-10?800 BP), when numerous cantabrian sites suffered high erosion processes. All these circumstances convert Cueva Oscura de Ania in a fundamental site to get a best knowledge of the origin and development of the Cantabrian Azilian. The study of its bone collection allows us outline new hypothesis about this archaeological period.  相似文献   
148.
The evolutionary pressures leading to the appearance of the cecal appendix, its evolutionary relationships with the cecum, and the link between these gastrointestinal characters and ecology remain controversial. We collected data on appendix presence and size, other gastrointestinal characters, ecological variables, dietary habits, and social characters hypothesized to drive appendix evolution for 533 mammalian species. Using phylogeny-informed analyses, we identified the first evidence of a positive correlation between appendix presence and cecal apex thickness, and a correlation with cecal morphology, suggesting that the appendix and cecum may be evolving as a module, the cecoappendicular complex. A correlation between appendix presence and concentration of cecal lymphoid tissue supports the hypothesis of an adaptive immune function for this complex. Other new findings include an inverse correlation between relative cecum length and habitat breadth, and positive relationships between cecum length and mean group size, and between colon length and weaning age.  相似文献   
149.
A broad range of soil pollutants were found to decrease with distance from a zinc smelter from 35,000 to 77, 8270 to 40 and from 190 to less than 1 ppm for zinc, lead and cadmium, respectively. Along this gradient, observed species richness of soil macro-organisms seemed to be more affected by the land-use type than by soil pollution--minimum in crops (21), maximum in woody sites (126). IndVal index allowed isolation of 21 indicator species from the 339 morphospecies identified. Most of these indicator species were characteristic of the unpolluted sites: only two diplopods and one gastropod from polluted poplar plantations, and none from the most polluted site. Since soil invertebrates respond to different environmental factors, including direct effect of heavy metals, we suggest there may be some confounding factors generating spurious relationships between the values of species as bioindicators and the pollution status they are supposed to indicate.  相似文献   
150.
In the germination of lipid-rich seeds, the glyoxylate cycle plays a control role in that, bypassing the two decarboxylative steps of the Krebs cycle; it allows the net synthesis of carbohydrates from lipids. The activity of isocitrate lyase, the key enzyme of the glyoxylate cycle, is an indicator of the state of seed germination: stage of germination, growth of embryo, activation and progress of protein synthesis, depletion of lipidic supplies. In order to investigate the effects of gravity on seed germination, we carried out a study on the time pattern of germination of Pinus pinea seeds that were subjected to a hypergravitational stress (1000 g for 64 h at 4 degrees C), either in a dry or in a wet environment, before to be placed in germination plates. During the whole time of germination, we monitored the state of embryo growth and the most representative enzymes of the main metabolic pathways. In treated wet seeds, we observed an average germination of only 20% with a slowdown of the enzyme activities assayed and a noticeable degradation of lipidic reserves with respect to the controls. These differences in germination are not found for dry seeds.  相似文献   
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