Design and synthesis of 3-(4-ethylphenyl)-2-substituted amino-3H-quinazolin-4-ones as a novel class of analgesic and anti-inflammatory agents

A new series of 3-(4-ethylphenyl)-2-substituted amino-3H-quinazolin-4-ones were synthesized by reacting the amino group of 2-hydrazino-3-(4-ethylphenyl)-3H-quinazolin-4-one from 4-ethyl aniline with a variety of aldehydes and ketones. The title compounds were investigated for analgesic, anti-inflammatory and ulcerogenic index activities. The compound 2-(N'-3-pentylidene-hydrazino)-3-(4-ethylphenyl)-3H-quinazolin-4-one (AS2) emerged as the most active compound of the series and was moderately more potent than the reference standard diclofenac sodium. Interestingly the test compounds showed only mild ulcerogenic potential when compared to aspirin.     

Agrobacterium-mediated transformation of leaf base derived callus tissues of popular indica rice (Oryza sativa L. sub sp. indica cv. ADT 43)

A simple and efficient protocol for the Agrobacterium-mediated transformation of an agronomically useful abiotic sensitive popular indica rice cv. ADT 43 has been developed. Initiation of calli were best achieved from the leaf bases of 4 days old rice seedlings on LS medium supplemented with 2.5 mg/L 2,4-D and 1.0 mg/L thiamine-HCl. Rice calli immersed in Agrobacterium suspension (strain EHA 105, OD₆₀₀ = 0.8) were co-cultured on LS30-AsPC medium for 2 days at 25 ± 2 °C in the dark. Based on GUS expression analysis, 10 min co-cultivation time with 100 μM acetosyringone was found optimum for the delivery of gus gene. Calli were proved to be very sensitive to Agrobacterium infection and we found that the level of necrotic response can be minimized after co-cultivation with 30% LS, 10 g/L PVP, 10% coconut water and 250 mg/L timentin which improved the final transformation efficiency to 9.33%. Molecular and genetic analysis of transgenic plants reveals the integration, expression and inheritance of transgene in the progeny (T₁) of these plants. The copy number of transgenes has been found to vary from 1 to 2 in transgenic plants (T₀ and T₁).     

Immunohistochemical Localization of Bone Morphogenetic Proteins (BMPs) and their Receptors in Solitary and Multiple Human Osteochondromas

The expression of bone morphogenetic proteins (BMPs) and their cognate receptors (BMPRs) in osteochondromas has not been investigated. We determined the immunohistochemical localization and distribution of BMP-2/4, -6 and -7; BMP receptors BMPR-1A, BMPR-1B and BMPR-2; signal transducing proteins phosphorylated Smad1/5/8; and BMP antagonist noggin in the cartilaginous cap of solitary (SO) and multiple (MO) human osteochondromas and compared these with bovine growth plate and articular cartilage. The distribution and localization patterns for BMP-6, BMP-7, BMPR-1A and BMPR-2 were similar between the cartilaginous cap and the growth plate. BMP-2/4 and BMPR-1B were present throughout the growth plate. However, BMP-2/4 and phosphorylated Smad1/5/8 were mainly detected in proliferating chondrocytes of the cartilaginous cap. Also, BMPR-1B was found in hypertrophic chondrocytes of SO and proliferating chondrocytes of MO. Noggin was observed in resting chondrocytes and, to a lesser extent, in clustered proliferating chondrocytes in SO. On the other hand, noggin in MO was observed in proliferating chondrocytes. Since BMPs can stimulate proliferation and hypertrophic differentiation of chondrocytes, these findings suggest that there is an imbalance of BMP-2/4 and noggin interactions that may lead to abnormal regulation of chondrocyte proliferation and differentiation in the cartilaginous cap of human osteochondromas.     

Application of centrality measures in the identification of critical genes in diabetes mellitus

The connectivity of a protein and its structure is related to its functional properties. Many experimental approaches have been employed for the identification of Diabetes Mellitus (DM) associated candidate genes. Therefore, it is of interest to use var ious graph centrality measures integrated with the genes associated with the human Diabetes Mellitus network for the identification of potential targets. We used 2728 genes known to cause Diabetes Mellitus from Jensenlab (Novo Nordisk Foundation Center for Protein Research, Denmark) for this analysis. A protein-protein interaction network was further constructed using a tool Centralities in Biological Networks (CentiBiN) with 1020 nodes after eliminating the duplicates, parallel edges, self -loop edges and unknown Human Protein Reference Database (HPRD) IDS. We used fourteen centralities measures which are useful in identifying the structural characteristic of individuals in the network. The results of the centrality measures are highly correlated. Thus, we identified genes that are critically associated with DM. We further report the top ten genes of all fourteen centrality measures for further consideration as targets for DM.     

Changes in pyrophosphatase activity during the de novo mineralization associated with cartilage and bone formation

Pyrophosphatase was extracted from implants undergoing de novo mineralization in an in vivo model of matrix-induced endochondral bone formation. Before the onset of the mineralization of the plaques and after the mineralization process had been completed only one form of pyrophosphatase activity was observed. During the active deposition of calcium phosphate, however, a new, higher molecular weight form of pyrophosphatase activity was produced suggesting that this enzyme activity is associated with biological mineralization. This observation gives support to the earlier suggestion that inhibitors of calcium phosphate precipitation, such as pyrophosphate, must be removed from the site of mineralization before calcification can occur. This high-molecular-weight activity also appears to be associated with alkaline and/or acid phosphatase activity as determined by molecular exclusion chromatography.     

Temporal changes in the response of chick limb bud mesodermal cells to transforming growth factor beta-type 1

Transforming growth factor beta (TGF beta) has been found in adult and developing bone in vivo and has varied effects on chondrocytes and osteoblasts in culture. We investigated the effects of TGF beta-type 1 on embryonic chick endochondral bone precursors in culture. Stage 24 chick limb bud mesoderm cells were cultured at high density. Under these conditions a dense mat containing nodules of cartilage surrounded by alkaline phosphatase-positive cells formed. Exposure of mesodermal cells to TGF beta-type 1 over the course of 4-7 days or during Days 3 and 4 caused a reduction in alkaline phosphatase activity and [35S]sulfate incorporation into proteoglycans. When the TGF beta-type 1 was applied during Days 1-2, it caused an increase in both parameters: these increases were observed in the absence of a corresponding change in [3H]thymidine incorporation. The specificity of the effects of TGF beta-type 1 was confirmed by neutralizing antibodies. These studies show that TGF beta-type 1 modulates the phenotype of embryonic endochondral bone precursors. The influence may depend on the window of exposure to the growth factor and, therefore, on the state of differentiation of the cells.     

Natural bovine osteogenin and recombinant human bone morphogenetic protein-2B are equipotent in the maintenance of proteoglycans in bovine articular cartilage explant cultures.

Osteogenin and related bone morphogenetic proteins are members of the transforming growth factor-beta superfamily, and were isolated by their ability to induce cartilage and bone formation in vivo. The influence of osteogenin, purified from bovine bone, and of recombinant human bone morphogenetic protein-2B (BMP-2B) has been examined in bovine articular cartilage explants. Both differentiation factors stimulated in a dose-dependent manner the synthesis of proteoglycans and decreased their rate of degradation. At a dose of 30 ng/ml, proteoglycan synthesis was increased to levels observed with either 20 ng/ml insulin-like growth factor I, 10 ng/ml transforming growth factor-beta, or 20% fetal bovine serum. This increase of biosynthetic rates above basal medium levels was observed in young, adolescent, and adult tissues. Analysis of the size of the newly synthesized proteoglycans, the glycosaminoglycan chain size, and the glycosaminoglycan type of explants treated with osteogenin or BMP-2B were very comparable to each other, and to proteoglycans isolated from cartilage treated with either insulin-like growth factor I or fetal bovine serum. These results demonstrate that osteogenin and BMP-2B alone are capable of stimulating and maintaining the chondrocyte phenotype in vitro.     

Changes in the gene expression of collagens, fibronectin, integrin and proteoglycans during matrix-induced bone morphogenesis

Subcutaneous implantation of demineralized bone matrix in rat results in the local cartilage and bone development. This in vivo model of bone formation was used to examine the expression patterns of cartilage and bone specific extracellular matrix genes. The steady state levels of mRNA in implants for cartilage specific type II collagen, type IX collagen, proteoglycan link protein and cartilage proteoglycan core protein (aggrecan) were increased during chondrogenesis and cartilage hypertrophy. Fibronectin mRNA levels were high during mesenchymal cell migration, attachment and chondrogenesis. Integrin (beta 1 chain) mRNA was expressed throughout the endochondral bone development. Type I collagen mRNA levels in implants increased as early as day 3, reached its peak during osteogenesis. These gene markers will be useful in the study of the mechanism of action of bone morphogenetic proteins present in the demineralized bone matrix.