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1.
Protoplasma - Watermelon and melon are members of the Cucurbitaceae family including economically significant crops in the world. The expansin protein family, which is one of the members of the...  相似文献   
2.
In this study the clastogenic effect of pyrimethamine (Daraprim), a folic acid antagonist used for the treatment of toxoplasmosis and malaria on human chromosomes, was investigated. Pyrimethamine was added to in vitro lymphocyte cultures at six different concentrations: 0.05 (normal therapeutic dose), 0.1, 0.2, 0.4, 0.8, and 1.6 mg/ml. No proliferation was observed in any of the cultures containing 1.6 mg/ml pyrimethamine. The results of the cytogenetic evaluations show that the frequency of breaks and gaps increase significantly in dose-dependent manner. Thus, pyrimethamine has a clastogenic effect on human chromosomes.Abbreviations PHAM Phytohemagglutinin M - M Metaphase - G Gap - B break - R Rearrangement - NCA Number Chromosome Abnormalities - FA Folic acid - SCE Sister Chromatid Exchange  相似文献   
3.
Diabetes mellitus is a serious worldwide metabolic disease, which is accompanied by hyperglycaemia and affects all organs and body system. Zinc (Zn) is a basic cofactor for many enzymes, which also plays an important role in stabilising the structure of insulin. Liver is the most important target organ after pancreas in diabetic complications. In this study, we aimed to investigate the protective role of Zn in liver damage in streptozotocin (STZ)‐induced diabetes mellitus. There are four experimental groups of female Swiss albino rats: group I: control; group II: control + ZnSO4; group III: STZ‐induced diabetic animals and group IV: STZ‐diabetic + ZnSO4. To induce diabetes, STZ was injected intraperitoneally (65 mg/kg). ZnSO4 (100 mg/kg) was given daily to groups II and IV by gavage for 60 days. At the end of the experiment, rats were killed under anaesthesia and liver tissues were collected. In the diabetic group, hexose, hexosamine, fucose, sialic acid levels, arginase, adenosine deaminase, tissue factor activities and protein carbonyl levels increased, whereas catalase, superoxide dismutase, glutathione‐S‐transferase, glutathione peroxidase, glutathione reductase and Na+/K+‐ATPase activities decreased. The administration of Zn to the diabetic group reversed all the negative effects/activities. According to these results, we can suggest that Zn has a protective role against STZ‐induced diabetic liver damage.  相似文献   
4.
In spite of the many developments in synthetic oligonucleotide (ON) chemistry and design, invasion into double-stranded DNA (DSI) under physiological salt and pH conditions remains a challenge. In this work, we provide a new ON tool based on locked nucleic acids (LNAs), designed for strand invasion into duplex DNA (DSI). We thus report on the development of a clamp type of LNA ON—bisLNA—with capacity to bind and invade into supercoiled double-stranded DNA. The bisLNA links a triplex-forming, Hoogsteen-binding, targeting arm with a strand-invading Watson–Crick binding arm. Optimization was carried out by varying the number and location of LNA nucleotides and the length of the triplex-forming versus strand-invading arms. Single-strand regions in target duplex DNA were mapped using chemical probing. By combining design and increase in LNA content, it was possible to achieve a 100-fold increase in potency with 30% DSI at 450 nM using a bisLNA to plasmid ratio of only 21:1. Although this first conceptual report does not address the utility of bisLNA for the targeting of DNA in a chromosomal context, it shows bisLNA as a promising candidate for interfering also with cellular genes.  相似文献   
5.
As computational capabilities increase, molecular dynamics (MD) simulations become important tools of simulating reality. These simulations are especially useful for compressible gas mixture problems. In this study, binary diffusion of helium and argon was examined using a hard-sphere MD simulation method. For the sake of computational speed, low spacing ratios were chosen. Binary mass diffusion of gases in two equally sized halves of a box was simulated for identical initial kinetic energies and number densities. It has been noted that a purely mass diffusion mechanism of different gases is not physically possible. The resultant gas mixtures of several diffusion simulations were used as initial conditions for combined heat transfer – Couette flow, and heating and cooling experiments. The results showed the interesting behaviour of the mixture, which was subjected to various wall conditions. Energy of heavier molecules is found to be more sensitive to the wall velocities and less sensitive to the wall temperatures than lighter molecules. Diffusion, heat transfer, viscosity and heat capacity coefficients are deduced as well.  相似文献   
6.
BtpA/Btp1/TcpB is a virulence factor produced by Brucella species that possesses a Toll interleukin-1 receptor (TIR) domain. Once delivered into the host cell, BtpA interacts with MyD88 to interfere with TLR signalling and modulates microtubule dynamics. Here the crystal structure of the BtpA TIR domain at 3.15 Å is presented. The structure shows a dimeric arrangement of a canonical TIR domain, similar to the Paracoccus denitrificans Tir protein but secured by a unique long N-terminal α-tail that packs against the TIR:TIR dimer. Structure-based mutations and multi-angle light scattering experiments characterized the BtpA dimer conformation in solution. The structure of BtpA will help with studies to understand the mechanisms involved in its interactions with MyD88 and with microtubules.  相似文献   
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8.
The objectives of this study were to evaluate both face and emotion recognition, to detect differences among attention deficit and hyperactivity disorder (ADHD) subgroups, to identify effects of the gender and to assess the effects of methylphenidate and atomoxetine treatment on both face and emotion recognition in patients with ADHD. The study sample consisted of 41 male, 29 female patients, 8–15 years of age, who were diagnosed as having combined type ADHD (N = 26), hyperactive/impulsive type ADHD (N = 21) or inattentive type ADHD (N = 23) but had not previously used any medication for ADHD and 35 male, 25 female healthy individuals. Long-acting methylphenidate (OROS-MPH) was prescribed to 38 patients, whereas atomoxetine was prescribed to 32 patients. The reading the mind in the eyes test (RMET) and Benton face recognition test (BFRT) were applied to all participants before and after treatment. The patients with ADHD had a significantly lower number of correct answers in child and adolescent RMET and in BFRT than the healthy controls. Among the ADHD subtypes, the hyperactive/impulsive subtype had a lower number of correct answers in the RMET than the inattentive subtypes, and the hyperactive/impulsive subtype had a lower number of correct answers in short and long form of BFRT than the combined and inattentive subtypes. Male and female patients with ADHD did not differ significantly with respect to the number of correct answers on the RMET and BFRT. The patients showed significant improvement in RMET and BFRT after treatment with OROS-MPH or atomoxetine. Patients with ADHD have difficulties in face recognition as well as emotion recognition. Both OROS-MPH and atomoxetine affect emotion recognition. However, further studies on the face and emotion recognition are needed in ADHD.  相似文献   
9.
The GTEx Consortium reported that hierarchical clustering of RNA profiles from 25 unique tissue types among 1641 individuals accurately distinguished the tissue types, but a multidimensional scaling failed to generate a 2D projection of the data that separates tissue-subtypes. In this study we show that a projection by t-Distributed Stochastic Neighbor Embedding is in line with the cluster analysis which allows a more detailed examination and visualization of human tissue relationships.  相似文献   
10.
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