Trigonella foenum graecum seed powder protects against histopathological abnormalities in tissues of diabetic rats

Premature visual impairment due to lens opacification is a debilitating characteristic of untreated diabetes. Lens opacification is primarily due to the insolubilization of crystallins, proteins essential for lens optical properties, and recent studies have suggested that a major cause of this insolubilization may be the unregulated proteolysis of crystallins by calpains. These are intracellular cysteine proteases whose activation requires the presence of calcium (Ca2+) and elevated levels of lens Ca2+ is a condition associated with both diabetic cataractogenesis and other forms of the disorder. A number of calpains have been identified in the lens, including calpain 2, calpain 10 and two isozymes of calpain 3: Lp82 and Lp85. The use of animal hereditary cataract models have suggested that calpain 2 and/or Lp82 may be the major calpains involved in murine cataractogenesis with contributions from calpain 10 and Lp85. However, calpain 2 appears to be the major calpain involved in murine diabetic cataractogenesis and the strongest candidate of the calpains for a role in human types of cataractogenesis. Here, we present an overview of recent evidence on which these observations are based with an emphasis on the ability of calpains to proteolyse lens crystallins and calpain structural features, which appear to be involved in the Ca2+-mediated activation of these enzymes.     

Lipoxygenase inhibiting and antioxidant oligostilbene and monoterpene galactoside from Paeonia emodi

Paeoninol and paeonin C, oligostilbene and monoterpene galactoside, have been isolated from the methanolic extract of the fruits of Paeonia emodi. Their structures have been assigned on the basis of spectral analysis including 1D and 2D NMR techniques. In addition, 4-hydroxybenzoic acid 3, gallic acid 4 and methyl gallate 5 have also been reported for the first time from this species. Compounds 1 and 2 have displayed potent inhibitory potential against enzyme lipoxygenase in a concentration-dependent fashion with the IC(50) values 0.77 and 99.5 microM, along with ABTS(.+) radical quenching activity with IC(50) values of 147.5 and 498.2 microM, respectively.     

Synthesis of aldehydo-sugar derivatives of pyrazoloquinoline as inhibitors of herpes simplex virus type 1 replication

Synthesis of a novel series of structurally related pyrazoloquinoline nucleosides is described. All the newly synthesized compounds were examined for their in vitro antiviral activity against herpes simplex type-1 as shown by two different bioassays, namely; crystal violet staining or the MTS tetrazolium dye measurement. The acute toxicity (LD50) values of the biologically active compounds were determined.     

The solution structure of ChaB,a putative membrane ion antiporter regulator from <Emphasis Type="Italic">Escherichia coli</Emphasis>

Background  

ChaB is a putative regulator of ChaA, a Na⁺/H⁺ antiporter that also has Ca⁺/H⁺ activity in E. coli. ChaB contains a conserved 60-residue region of unknown function found in other bacteria, archaeabacteria and a series of baculoviral proteins. As part of a structural genomics project, the structure of ChaB was elucidated by NMR spectroscopy.     

Structure of the archaeal translation initiation factor aIF2 beta from Methanobacterium thermoautotrophicum: implications for translation initiation

aIF2 beta is the archaeal homolog of eIF2 beta, a member of the eIF2 heterotrimeric complex, implicated in the delivery of Met-tRNA(i)(Met) to the 40S ribosomal subunit. We have determined the solution structure of the intact beta-subunit of aIF2 from Methanobacterium thermoautotrophicum. aIF2 beta is composed of an unfolded N terminus, a mixed alpha/beta core domain and a C-terminal zinc finger. NMR data shows the two folded domains display restricted mobility with respect to each other. Analysis of the aIF2 gamma structure docked to tRNA allowed the identification of a putative binding site for the beta-subunit in the ternary translation complex. Based on structural similarity and biochemical data, a role for the different secondary structure elements is suggested.     

Intracerebral microdialysis and its clinical application: a review

In vivo intracerebral microdialysis is an important neurochemical technique that has been used extensively in the experimental setting. Relatively recently, techniques have been developed to utilize this method in human subjects. The past decade has seen the advent of clinical investigations utilizing in vivo microdialysis in a number of neuropathological states. This review summarizes the principles of in vivo microdialysis techniques, as applied to humans, while discussing the significance of recent investigations for future clinical development.     

Isolation of a cDNA encoding an IgG immunoreactive antigen (zinc finger protein) of Strongyloides stercoralis

A full length cDNA encoding an IgG immunoreactive antigen of Strongyloides stercoralis is described. A clone containing 1,328 bp insert was selected following screening of S. stercoralis cDNA library with an IgG fraction obtained from a pool of 78 S. stercoralis positive human sera samples. The nucleotide sequence of the 1,328 bp insert was found to be 70.5% A/T, reflecting a characteristic A/T codon bias of S. stercoralis. The nucleotide sequence of this insert identified a cDNA coding for a zinc finger protein. The conceptually translated amino acid sequence of the open reading frame for the IgG immunoreactive antigen of S. stercoralis encodes a 211 amino acid residue protein with an apparent molecular weight of 22.8 kDa and a predicted isoelectric point of 8.71. The diagnostic potential of this IgG immunoreactive antigen of S. stercoralis is also discussed.     

An isopyoverdin from Pseudomonas putida CFML 90-44

From Pseudomonas putida CFML 90-44 an isopyoverdin was isolated. Its structure could be elucidated by chemical degradation and spectroscopic data.     

The primary antibody repertoire represents a linked network of degenerate antigen specificities

In this study, germline Abs were used to select clones from a random dodecapeptide phage-display library. This revealed a much greater heterogeneity of binders than could be obtained with mutated daughter Abs that presumably had been selected in vivo by nominal Ag during active immune responses. We demonstrate that the pluripotency of germline Abs can subsequently be optimized by binding interactions that correlate with thermodynamic changes indicative of structural adaptations at the interface. This singular feature confers on each Ab a distinct window of Ag specificities, where the entropic space explored constitutes a thermodynamic signature of that particular Ab. Combining site plasticity may facilitate overlaps in such windows, with independent Abs converging onto common determinants with near identical binding affinities. In addition to providing for an amplified recognition potential, this networking of individual spectra of Ag specificities simultaneously facilitates the rapid recognition of Ag. Importantly, it also ensures that the primary response is composed of Abs with a high degree of "evolvability."