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21.
Hannah Gardener Della David Morte Mitchell SV Elkind Ralph L Sacco Tatjana Rundek 《BMC cardiovascular disorders》2009,9(1):1-8
Background
Heterogeneity in B-type natriuretic peptide (BNP) levels, especially among individuals with acute heart failure with normal left ventricular ejection fraction (HFNEF), can cause confusion in interpreting results. We investigated the characteristics of cases of acute HFNEF with only modestly elevated BNP.Methods
One hundred forty-two patients with acute or acute exacerbation of chronic HFNEF were divided into two groups by BNP level: BNP < 100 pg/ml (NB group, n = 45) and BNP ≥ 100 pg/ml (B group, n = 97). We compared clinical findings, echocardiography results, and neurohormonal factors between these two groups.Results
In the NB group, a history of open-heart surgery (OHS) was more frequent (71% vs. 22%, p < 0.0001) and hypertension was less frequent (p = 0.0005). Left atrial diameter (LAd) was higher (p = 0.0026), while interventricular septal thickness, posterior wall thickness, relative wall thickness, left ventricular mass index were lower (p = 0.0005, p = 0.0225, p = 0.0114, p = 0.0051, respectively) in the NB group. In patients with HFNEF, a history of OHS remained an independent predictor of BNP level (< 100 pg/ml) after adjustment for hypertension, age, LAd, and interventricular septal thickness (odds ratio 3.6, p = 0.0252).Conclusion
We found associations between acute HFNEF with less elevated BNP and a history of OHS. In a patient suspected of HFNEF, a history of OHS is considered diagnostic evidence of presence of diastolic heart failure when plasma levels of BNP are less elevated. 相似文献22.
Biologically active polypeptides of sea anemones: Structure, function, and prospects for application
V. M. Tabakmakher M. M. Monastyrnaya E. V. Leichenko I. N. Gladkikh E. A. Zelepuga V. E. Chausova E. S. Tkacheva I. G. Agafonova E. P. Kozlovskaya 《Russian Journal of Marine Biology》2013,39(5):311-320
This paper presents the results of a structure-functional study of neurotoxins, actinoporins, and proteinase inhibitors from the tropical sea anemone Heteractis crispa (= Radianthus macrodactylus) and the low boreal sea anemone Oulactis orientalis. The new data significantly contribute to the knowledge of the mechanisms of action of polypeptides from marine coelenterates and can be useful for solving practical problems of the biotechnological development of medicines. 相似文献
23.
A low-molecular-weight water-soluble chitosan was obtained from high-molecular-weight crab chitosan using the enzyme preparation Celloviridine G20x. Optimum conditions for the enzymatic hydrolysis were designed. The reaction should be performed for 4 h in a sodium-acetate buffer (pH 5.2) at 55 degrees C and the enzyme to substrate ratio of 1:400. Fractional extraction of chitosan hydrolysate by aqueous ethanol (ethanol: distilled water) yielded fractions with molecular weights in the range 3.2-26.4 kDa. 相似文献
24.
Sozinov AS Anikhovskaia IA Baiazitova LT Enaleeva DSh Zinkevich OD Salakhov IM Tkacheva SV Likhoded VG 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2002,(1):61-64
In chronic viral hepatitis B and C the development of intestinal dysbacteriosis and high occurrence of concomitant diseases of the gastrointestinal tract were observed. In cases of increased dysbacteriosis degree and in the presence of concomitant diseases the blood plasma of patients exhibited higher activity in reaction with the of amebocytes lysate obtained from crabs of the genus Limulus. A suggestion was made that the endotoxin of Gram negative intestinal microflora could probably play some role in the development of pathological processes in chronic viral hepatitis B and C. 相似文献
25.
26.
Abstract A new species of nematode, Heth baudini sp. n. from a diplopod (Spirostreptida: Iulomorphidae Verhoeff, 1924) collected in Queensland, Australia, is described and illustrated. The cephalic and cervical cuticular ornamentation of females of H. baudini sp. n. is similar to those of South-East Asian and Australasian Heth species. Heth baudini sp. n. females are particularly close to Heth taynguyeni from Vietnam but can be distinguished by the shape of the lateral lappets, which in H. taynguyeni limit the trapezium-shaped region of smooth cuticle unlike the elliptical region in H. baudini sp. n., and by the presence of lateral spines only half the size. The cuticle of the H. baudini sp. n. is finely annulated along the entire body, whereas H. taynguyeni has broader rings behind the first pair of lateral spines, each consisting of five or six narrower rings separated from each other by deeper furrows. Males of H. baudini sp. n. are characterised by the presence of a bursa-like fold on the tail and can be distinguished from other species of the genus by the presence of somatic papillae embedded into the bursal fold. 相似文献
27.
Tkacheva ES Leychenko EV Monastyrnaya MM Issaeva MP Zelepuga EA Anastuk SD Dmitrenok PS Kozlovskaya EP 《Biochemistry. Biokhimii?a》2011,76(10):1131-1139
A new actinoporin Hct-S4 (molecular mass 19,414 ± 10 Da) belonging to the sphingomyelin-inhibited α-pore forming toxin (α-PFT)
family was isolated from the tropical sea anemone Heteractis crispa (also called Radianthus macrodactylus) and purified by methods of protein chemistry. The N-terminal nucleotide sequence (encoding 20 amino acid residues) of actinoporin Hct-S4 was determined. Genes encoding 18 new
isoforms of H. crispa actinoporins were cloned and sequenced. These genes form a multigene Hct-S family characterized by presence of N-terminal serine in the mature proteins. Highly conserved residues comprising the aromatic phosphorylcholine-binding site
and significant structure-function changes in the N-terminal segment (10–27 amino acid residues) of actinoporins were established. Two expressed recombinant actinoporins (rHct-S5
and rHct-S6) were one order less hemolytically active than native actinoporins. 相似文献
28.
Comparative studies of the frequency and spectrum of pathological mitoses (PMs), as well as of the nucleolus number in the interphase nucleus, in cells of Norway spruce (Picea abies (L.) Karst.) seedlings were carried out in two natural populations of Ukrainian Polesie and plants from an introduction plantation in Donbass. Low levels of PMs in the seed progeny of the populations (0.32?C0.38%) and a slightly higher level in the plantation progeny (0.40%) are established. The number of nucleoli was somewhat higher in the progeny of the populations (5.35?C5.85) than that of the plantation plants (4.95). The PMs frequency was higher (0.43%) in the progeny of low-heterozygous plants than in highly heterozygous ones (0.28%). 相似文献
29.
Kshitiz?GuptaEmail author Dina?Thomas SV?Vidya KV?VenkateshEmail author S?Ramakumar 《BMC bioinformatics》2005,6(1):105
Background
The chemical property and biological function of a protein is a direct consequence of its primary structure. Several algorithms have been developed which determine alignment and similarity of primary protein sequences. However, character based similarity cannot provide insight into the structural aspects of a protein. We present a method based on spectral similarity to compare subsequences of amino acids that behave similarly but are not aligned well by considering amino acids as mere characters. This approach finds a similarity score between sequences based on any given attribute, like hydrophobicity of amino acids, on the basis of spectral information after partial conversion to the frequency domain. 相似文献30.
Estimating synonymous and nonsynonymous substitution rates 总被引:8,自引:4,他引:4
Partitioning the total substitution rate into synnonymous and nonsynonymous
components is a key aspect of many analyses in molecular evolution.
Numerous methods exist for estimating these rates. However, until recently
none of the estimation procedures were based on a sound statistical
footing. In this paper, the evolutionary model of Muse and Gaut (1994) is
used as the basis for two sets of parameters quantifying silent and
replacement substitution rates. The parameters are shown to be equal when
the four nucleotides are equally frequent and unequal otherwise.
Maximum-likelihood estimation of these parameters is described, and the
performance of these estimates is compared to that of existing estimation
procedures. It is shown that the estimates of Nei and Gojobori (1986) are
not unbiased for either set of parameters, although they provide very good
estimates for one set as long as sequence divergence is not too high.
However, some disturbing properties are found for the Nei and Gojobori
estimates. In particular, it is shown that the expected value of the Nei
and Gojobori estimate of silent substitution rate is a function of both the
silent and replacement substitution rates. The maximum-likelihood estimates
have no such problems.
相似文献