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1.
The tumor-associated transmembrane carbonic anhydrase (CA, EC 4.2.1.1) isozymes IX (CA IX) and XII (CA XII) are involved in acidification of hypoxic tumors, a process correlated with poor prognosis and clinical outcome of patients harboring such tumors. This process may be reversed by inhibiting these enzymes with potent sulfonamide/sulfamate inhibitors. A series of such aromatic/heterocyclic sulfonamides incorporating 2,3,5,6-tetrafluorobenzoyl-, 2,3,5,6-tetrafluoro- phenylsulfonyl- and pentafluorophenylureido moieties has been investigated for its interaction with the catalytic domain of the human isozymes hCA IX and hCA XII. Some of these compounds showed excellent inhibitory properties against both isozymes IX and XII, with several subnanomolar inhibitors detected for the first time. These sulfonamides may constitute valuable candidates for the development of novel antitumor therapies based on the inhibition of such tumor-associated CA isozymes.  相似文献   
2.
Summary We lay new foundations to the hypothesis that the genetic code is adapted to evolutionary retention of information in the antisense strands of natural DNA/RNA sequences. In particular, we show that the genetic code exhibits, beyond the neutral replacement patterns of amino acid substitutions, optimal properties by favoring simultaneous evolution of proteins encoded in DNA/RNA sense-antisense strands. This is borne out in the sense-antisense transformations of the codons of every amino acid which target amino acids physicochemically similar to each other. Moreover, silent mutations in the sense strand generate conservative ones in its antisense counterpart and vice versa. Coevolution of proteins coded by complementary strands is shown to be a definite possibility, a result which does not depend on any physical interaction between the coevolving proteins. Likewise, the degree to which the present genetic code is dedicated to evolutionary sense-antisense tolerance is demonstrated by comparison with many randomized codes. Double-strand coding is quantified from an information-theoretical point of view.  相似文献   
3.
Glucocorticoids act via glucocorticoid receptors (GR), typically localized in the cytosol (cGR). Rapid action is probably mediated via membrane receptors (mGR). In corticotropin-releasing hormone knockouts (CRH-KO), basal plasma glucocorticoid levels do differ from wild type levels (WT), but are approximately ten times lower during exposure to immobilization stress (IMMO) in comparison to WT. We tested the following hypotheses: (1) the mice lung tissue GR basal numbers would not be changed in CRH-KO (because of similar glucocorticoid levels), (2) the number of GR would be changed in WT but not in KO during short (30, 90, and 120 min) IMMO (because of higher increase of glucocorticoid levels in WT). The basal levels of cGR were not changed in CRH-KO (compared to WT), while mGR were significantly lower (62 %) in CRH-KO. In WT, there was the only decrease (to 32 %) in cGR after 120 min when we also found an increase in mGR in WT (to 201 %). In CRH-KO, IMMO caused gradual decrease in cGR (to 52 % after 30 min, to 46 % after 90 min, and to 32 % after 120 min). In CRH-KO, the only increase in mGR appeared already at 30 min of IMMO. These data suggest, on the contrary to our hypotheses, that CRH-KO are more susceptible to GR changes in early phases of stress.  相似文献   
4.
Yilmaz  Şehnaz  Yoldas  Oguz  Dumani  Aysin  Guler  Gizem  Ilgaz  Seda  Akbal  Eylül  Oksuz  Hale  Celik  Ayla  Yilmaz  Bertan 《Molecular biology reports》2020,47(7):5377-5383
Molecular Biology Reports - Antimicrobial irrigation solutions are widely used under clinical settings. Their effect on dental tissue is a subject of recent research, which aims for a safer...  相似文献   
5.
Aslan  Abdullah  Beyaz  Seda  Gok  Ozlem  Erman  Orhan 《Molecular biology reports》2020,47(4):2573-2582
Molecular Biology Reports - The goal of this study was to determine the protective role of ellagic acid (EA) against CCl4-induced muscle injury in rats. In this study, 36 Wistar albino rats...  相似文献   
6.
Grand canonical Monte Carlo and equilibrium molecular dynamics simulations were used to assess the performance of an rht-type metal–organic framework (MOF), Cu-TDPAT, in adsorption-based and membrane-based separation of CH4/H2, CO2/CH4 and CO2/H2 mixtures. Adsorption isotherms and self-diffusivities of pure gases and binary gas mixtures in Cu-TDPAT were computed using detailed molecular simulations. Several properties of Cu-TDPAT such as adsorption selectivity, working capacity, diffusion selectivity, gas permeability and permeation selectivity were computed and compared with well-known zeolites and MOFs. Results showed that Cu-TDPAT is a very promising adsorbent and membrane material especially for separation of CO2 and it can outperform traditional zeolites and MOFs such as DDR, MFI, CuBTC, IRMOF-1 in adsorption-based CO2/CH4 and CO2/H2 separations.  相似文献   
7.
ABSTRACT

Circadian disruption has been linked with immune-related morbidities including autoimmune diseases. PERIOD3 (PER3) clock gene is a key player in the mammalian circadian system. This study evaluated the possible association of PER3 rs2797685 (G/A) polymorphism and susceptibility of autoimmune thyroid diseases (AITD) and assessed if this SNP contributes to disease characteristics and serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). The PER3 rs2797685 (G/A) polymorphism was assessed in 125 patients with AITD [Graves’ disease (GD), 69; Hashimoto’s thyroiditis (HT), 56] and 115 unrelated healthy controls. Subjects carrying at least one variant allele of PER3 rs2797685 (GA+AA) had increased risk for GD (OR 1.9, 95% CI 1–3.61, p= .05). There were no differences in the frequencies of genotypes and alleles of the PER3 rs2797685 polymorphism between HT patients and control subjects. No association was observed between genotypes of the studied SNP and any of the disease characteristics in GD and HT patients. The GA+AA genotype of PER3 rs2797685 was associated with lower levels of IL-6 in patients with Graves’ disease. There were no differences between genotypes of the studied SNP regarding TNF-α levels in GD, HT or control groups. In conclusion, this study provides the first evidence for a genetic association between GD and the PER3 gene, highlighting the possible relevance of polymorphisms in clock genes in the etiopathogenesis of AITD. However, functional studies to identify the underlying molecular mechanisms of this association are needed to translate these findings to clinical applications.  相似文献   
8.
Long-term persistence of a Daphnia population is allowed by the production of dormant stages, produced mostly through sexual reproduction. We investigated the spatio-temporal dynamics of male production in a spring population of Daphnia galeata in the reservoir, and compared the genetic structure of three groups within this population: male-, female-producing females, and adult males. With a fine resolution sampling design and the use of highly variable microsatellite markers we revealed that: (1) the spring period of male offspring production was delimited in time with minimum interannual variation to about 3 weeks, and in space to the upper 5-m water layer; (2) there were no remarkable changes in the clonal composition of male-producing females within the period of male production; (3) overall certain clones exhibited a higher tendency to produce male offspring and therefore the clonal structure of male-producing lineages was significantly different from that of female-producing lineages; and (4) the clonal structure of male-producing females was not significantly different from that of adult males occurring later in the reservoir. This suggests that males were not subjected to any significant selective forces till maturity and the male-producing females confer a long-term fitness advantage over female-producing females.  相似文献   
9.
10.
Four chiral C2‐symmetric diols were synthesized in a straightforward three‐step reaction and demonstrated excellent enantioselectivities and good overall yields. Their catalytic activities were examined via the addition of diethylzinc to various aldehydes. The enantioselective addition of diethylzinc to 2‐methoxybenzaldehyde gave the corresponding chiral secondary alcohol with high yields (up to 95%) and moderate to good enantiomeric excess (up to 88%). All synthesized ligands were evaluated in the addition of diethylzinc to various aldehydes in the presence of an additional metal such as Ti(IV) complexes. Chirality 28:593–598, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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