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101.
Arostropsis groehnigen. et sp. n. is described from Baltic amber and temporarily placed in the tribe Naupactini. It differs from all recent Naupactini genera with open corbels by very short and flattened scape, distinct lateral carina of the pronotum and elytra, and the rostrum distinctly narrower than the head capsule. The shape of head in the extinct genus is somewhat similar to that of the extant Naupactini genera with enclosed corbels (Platyomus Sahlberg, 1823 and Aptolemus Schoenherr, 1842), but differs in the slender body, open corbels, very short antennal scape and epifrons without a median sulcus (only a longitudinal depression is slightly visible). It is also similar to the Tanymecine genus Pandeleteius Schoenherr, 1834 in general appearance, but distinct by the straight anterior edge of the pronotum, lack of postocular spurs, lobes, and vibrissae, a slightly sloping elytral declivity, lateral ridges on the pronotum, subflattened antennal scape, elongate rostrum, and sparsely setose epistome. A new synonymy of the generic names Protonaupactus Zherikhin, 1971 and Sucinophyllobius Wanat & Borowiec, 1986, syn. n., is established. The Madagascan genus Corecaulus Fairmaire, 1903 is transferred from the tribe Naupactini to the Brachyderini because of its connate claws and the similarity in chaetotaxy of the epistomal area with African and Madagascar Brachyderini genera. A key to the identification of known Baltic amber genera of Entiminae is proposed. A checklist of the prepleistocene fossil Entiminae, based on V.V. Zherikhin's data, with remarks and corrections, is presented. 相似文献
102.
Jes Jessen Rasmussen Annette Baattrup-Pedersen Tenna Riis Nikolai Friberg 《Aquatic Ecology》2011,45(2):231-242
We surveyed macrophyte community structure and measured community metabolism and nutrient uptake along a temperature gradient
(9.7–17.4°C) in four Icelandic streams influenced by geothermal heating. The study streams are part of the geothermal area
in Hengill that is uniquely characterised by streams with comparable water chemistry despite the geothermal influence. Stream
metabolism was studied applying the diurnal upstream–downstream dissolved oxygen change technique. Nutrient uptake was studied
by adding solutions of nitrogen and phosphorus together with a conservative tracer. Rates of primary production (GPP) and
uptake of nitrate–N and phosphate-P increased with increasing stream temperature. GPP was 20 times higher (up to 12.99 g O2 m−2 day−1) and rates of nutrient uptake were up to 30-times higher (up to 22.99, 13.31 and 7.94 mg m−2 h−1 for ammonium, nitrate and phosphate, respectively) in the warmest streams compared with the coldest. Furthermore, macrophytes,
when present, were strongly controlling ecosystem processes. Our study implies that temperature may affect stream ecosystem
processes both directly (i.e. physiologically) and indirectly (i.e. by changing other structural parameters). 相似文献
103.
Lussier YA Xing HR Salama JK Khodarev NN Huang Y Zhang Q Khan SA Yang X Hasselle MD Darga TE Malik R Fan H Perakis S Filippo M Corbin K Lee Y Posner MC Chmura SJ Hellman S Weichselbaum RR 《PloS one》2011,6(12):e28650
Background
Cancer staging and treatment presumes a division into localized or metastatic disease. We proposed an intermediate state defined by ≤5 cumulative metastasis(es), termed oligometastases. In contrast to widespread polymetastases, oligometastatic patients may benefit from metastasis-directed local treatments. However, many patients who initially present with oligometastases progress to polymetastases. Predictors of progression could improve patient selection for metastasis-directed therapy.Methods
Here, we identified patterns of microRNA expression of tumor samples from oligometastatic patients treated with high-dose radiotherapy.Results
Patients who failed to develop polymetastases are characterized by unique prioritized features of a microRNA classifier that includes the microRNA-200 family. We created an oligometastatic-polymetastatic xenograft model in which the patient-derived microRNAs discriminated between the two metastatic outcomes. MicroRNA-200c enhancement in an oligometastatic cell line resulted in polymetastatic progression.Conclusions
These results demonstrate a biological basis for oligometastases and a potential for using microRNA expression to identify patients most likely to remain oligometastatic after metastasis-directed treatment. 相似文献104.
Myocardial remodeling is a major contributor in the development of heart failure (HF) after myocardial infarction (MI). Integrin-linked kinase (ILK), LIM-only adaptor PINCH-1, and α-parvin are essential components of focal adhesions (FAs), which are highly expressed in the heart. ILK binds tightly to PINCH-1 and α-parvin, which regulates FA assembly and promotes cell survival via the activation of the kinase Akt. Mice lacking ILK, PINCH or α-parvin have been shown to develop severe defects in the heart, suggesting that these proteins play a critical role in heart function. Utilizing failing human heart tissues (dilated cardiomyopathy, DCM), we found a 2.27-fold (p<0.001) enhanced expression of PINCH, 4 fold for α-parvin, and 10.5 fold (p<0.001) for ILK as compared to non-failing (NF) counterparts. No significant enhancements were found for the PINCH isoform PINCH-2 and parvin isoform β-parvin. Using a co-immunoprecipitation method, we also found that the PINCH-1-ILK-α-parvin (PIP) complex and Akt activation were significantly up-regulated. These observations were further corroborated with the mouse myocardial infarction (MI) and transaortic constriction (TAC) model. Thymosin beta4 (Tβ4), an effective cell penetrating peptide for treating MI, was found to further enhance the level of PIP components and Akt activation, while substantially suppressing NF-κB activation and collagen expression--the hallmarks of cardiac fibrosis. In the presence of an Akt inhibitor, wortmannin, we show that Tβ4 had a decreased effect in protecting the heart from MI. These data suggest that the PIP complex and activation of Akt play critical roles in HF development. Tβ4 treatment likely improves cardiac function by enhancing PIP mediated Akt activation and suppressing NF-κB activation and collagen-mediated fibrosis. These data provide significant insight into the role of the PIP-Akt pathway and its regulation by Tβ4 treatment in post-MI. 相似文献
105.
106.
Nordsborg N Thomassen M Lundby C Pilegaard H Bangsbo J 《American journal of physiology. Regulatory, integrative and comparative physiology》2005,289(1):R84-R91
The present study tested the hypothesis that exercise with a large compared with a small active muscle mass results in a higher contraction-induced increase in Na(+)-K(+)-ATPase mRNA expression due to greater hormonal responses. Furthermore, the relative abundance of Na(+)-K(+)-ATPase subunit alpha(1), alpha(2), alpha(3), alpha(4), beta(1), beta(2), and beta(3) mRNA in human skeletal muscle was investigated. On two occasions, eight subjects performed one-legged knee extension exercise (L) or combined one-legged knee extension and bilateral arm cranking (AL) for 5.00, 4.25, 3.50, 2.75, and 2.00 min separated by 3 min of rest. Leg exercise power output was the same in AL and L, but heart rate at the end of each exercise interval was higher in AL compared with L. One minute after exercise, arm venous blood lactate was higher in AL than in L. A higher level of blood epinephrine and norepinephrine was evident 3 min after exercise in AL compared with L. Nevertheless, none of the exercise-induced increases in alpha(1), alpha(2), beta(1), and beta(3) mRNA expression levels were higher in AL compared with L. The most abundant Na(+)-K(+)-ATPase subunit at the mRNA level was beta(1), which was expressed 3.4 times than alpha(2). Expression of alpha(1), beta(2), and beta(3) was less than 5% of the alpha(2) expression, and no reliable detection of alpha(3) and alpha(4) was possible. In conclusion, activation of additional muscle mass does not result in a higher exercise-induced increase in Na(+)-K(+)-ATPase subunit-specific mRNA. 相似文献
107.
Novel type of hepatitis B virus mutation: replacement mutation involving a hepatocyte nuclear factor 1 binding site tandem repeat in chronic hepatitis B virus genotype E 下载免费PDF全文
Fujiwara K Tanaka Y Paulon E Orito E Sugiyama M Ito K Ueda R Mizokami M Naoumov NV 《Journal of virology》2005,79(22):14404-14410
108.
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A new off-resonance spin-lock experiment to record relaxation dispersion profiles of amide protons is presented. The sensitivity-enhanced
HSQC-type sequence is designed to minimize the interference from cross-relaxation effects and ensure that the dispersion profiles
in the absence of μs-ms time-scale dynamics are flat. Toward this end (i) the proton background is eliminated by sample deuteration (Ishima et al., 1998), (ii) 1H spin lock is applied to two-spin modes 2(HxSin ϑ + HzCos ϑ)
Nz, and (iii) the tilt angle ϑ ≈ 35° is maintained throughout the series of measurements (Desvaux et al. Mol. Phys., 86 (1995) 1059). The relaxation dispersion profiles recorded in this manner sample a wide range of effective rf field strengths
(up to and in excess of 20 kHz) which makes them particularly suitable for studies of motions on the time scale ≤100 μs. The
new experiment has been tested on the Ca2+-loaded regulatory domain of cardiac troponin C. Many residues show pronounced dispersions with remarkably similar correlation
times of 30 μs. Furthermore, these residues are localized in the regions that have been previously implicated in conformational
changes (Spyracopoulos et al. Biochemistry, 36 (1997) 12138)
Electronic supplementary material Electronic supplementary material is available for this article at
and accessible for authorised users. 相似文献