AFLP reveals structural details of genetic diversity within cultivated olive germplasm from the Eastern Mediterranean

Amplified fragment length polymorphism (AFLP) analysis was used to assess genetic inter-relationships among olive varieties cultivated in the Eastern Mediterranean Basin. The genotypes sampled included most of the important cultivars from Turkey, Greece and the Middle East and selected genotypes from the Western Mediterranean area. A total of 119 polymorphic markers were generated from five selective primer-pair combinations. The combined data sets generated by just two primer-pairs were adequate to discriminate between all 65 genotypes, while each primer-pair could individually identify up to 64 genotypes. A factorial correspondence analysis (FCA) plot indicated that the cultivars clustered into two relatively modestly defined groups. The first broad group was dominated by cultivars from Turkey but also included genotypes originating from the Middle East (Syria and Lebanon) that collectively formed a tight subcluster. The second group comprised Greek cultivars and those originating from the Western Mediterranean. A significant genetic distance value between Greek and Turkish cultivars was provided by an analysis of molecular variance (amova). There was also evidence of substructure here, with an apparent separation of most Spanish and Italian clones. These findings are in general accordance to previous suggestions of an East-West divergence of olive cultivars, although the dichotomy is less extensive than reported previously and complicated by regional variation within each group.     

Design, synthesis, and antiproliferative activity of some novel aminosubstituted xanthenones, able to overcome multidrug resistance toward MES-SA/Dx5 cells

A series of novel xanthenone aminoderivatives and their pyrazole-fused counterparts possessing structural analogy to the potent anticancer agent 9-methoxypyrazoloacridine (PZA) reported. These compounds exhibited an interesting cytotoxic activity against a panel of cell lines. Most noticeably, they retain activity against the multidrug resistant MES-SA/Dx5 subline, showing resistant factors close to 1.     

Regulation of expression and function of Lck tyrosine kinase by high cell density

For many types of cells, an increase in cell density leads to characteristic changes in intracellular signalling and cell function. It is unknown, however, whether cell density affects the function of T lymphocytes. It is presented here that aggregation of Jurkat T cells, murine thymocytes or human peripheral blood T cells, results in gradual modification of the Lck tyrosine kinase. Within one hour of aggregation, Lck in the detergent-insoluble lipid raft fraction is dephosphorylated mainly at the carboxy-terminal tyrosine. Further aggregation leads to gradual loss of Lck protein from both lipid raft and non-raft fractions which is accompanied by increased protein ubiquitination, a process that is more evident in the detergent-soluble fraction. In contrast, the expression of LAT, which like Lck distributes to raft and non-raft membrane, or Csk, a kinase with a structure similar to Lck, is not affected by cell aggregation. Dephosphorylation of lipid raft-associated Lck, albeit with reduced kinetics, is observed in aggregated Jurkat CD45-deficient cells as well, suggesting involvement of additional tyrosine phosphatases. Changes in Lck structure and expression correlate with reduced ability of aggregated cells to fully activate protein tyrosine phosphorylation after stimulation of the TCR, and with changes in the activation of down-stream signalling cascades.     

Experience with a thin-layer,liquid-based cervical cytologic screening method

OBJECTIVE: To assess the utility of a thin-layer cytology system for cervicovaginal screening in clinical practice. STUDY DESIGN: Twenty-five hundred cervicovaginal split samples were processed with the traditional direct smearing method and with the ThinPrep Pap Test (Cytyc Corp., Boxborough, Massachusetts, U.S.A.) method and evaluated according to the Bethesda system, focusing mainly on the cytomorphologic features. RESULTS: The ThinPrep Pap Test yielded improved specimen adequacy and an increased detection rate of squamous abnormalities, which resulted in a decrease in the ASCUS/SIL ratio. Moreover, the thin-layer system provided adequate material for concomitant HPV testing, mainly in the LSIL and the ASCUS favor SIL cases, with satisfactory results, as well as for cell block preparations in a few selected cases that presented diagnostic difficulties. Furthermore, the morphologic features of the LSIL cases were virtually identical on both preparations, while in the HSIL cases, distinct features were noted on ThinPrep. CONCLUSION: The ThinPrep Pap Test is significantly more effective than the conventional smear in clinical practice. However, training and experience are necessary to take full advantage of this promising new technology.     

Pancreatic polypeptide in pancreatitis

Pancreatitis is a disease with increasing incidence which can be divided into an acute and a chronic form. In both acute and chronic pancreatitis, changes in plasma concentration of pancreatic polypeptide (PP) and its regulation have been reported. In daily clinical work a serologic test for the precise diagnosis and staging of acute and chronic pancreatitis is still desirable. Therefore, many studies have investigated plasma concentrations of PP in acute and chronic pancreatitis as a diagnostic marker and as a therapeutic option to treat pancreatogenic diabetes mellitus. Although the study results are presently inconclusive and potentially contradictory, the findings are nevertheless encouraging, and indicate that PP might have a role in diagnosis, grading and estimation of the prognosis of pancreatitis. Further data and prospective controlled studies are needed to judge whether PP is of clinical value for diagnosing, staging and predicting long-term outcome in acute and chronic pancreatitis.     

Mixed chloride-phosphine complexes of the dirhenium core. Part 11. Reactions of [Re2Cl8] with secondary phosphines, PCy2H and PPh2H

The reaction between the dirhenium(III,III) anion, [Re₂Cl₈]²⁻, and the secondary phosphine, PCy₂H, yields a mixture of products as a result of disproportionation, namely, a dirhenium(II,III) chloride-phosphine complex 1,3,6-Re₂Cl₅(PCy₂H)₃ (1) and a dirhenium(IV) face-sharing bioctahedral compound with bridging phosphido groups, [Buⁿ ₄N][Re₂(μ-PCy₂)₃Cl₆] (2). The diphenylphosphine analogue of 2, [Buⁿ ₄N][Re₂(μ-PPh₂)₃Cl₆] (3) has been similarly prepared from the reaction of [Re₂Cl₈]²⁻ with PPh₂H. An interesting dirhenium(III,III) complex, [Buⁿ ₄N]₂[Re₂(μ-PPh₂)₂(PPh₂H)₂Cl₆] (4) having both neutral terminal phosphines and anionic phosphido bridges, has also been isolated as an intermediate in the latter system. Crystal structures of 1-4 have been determined by X-ray crystallography. The compounds were also characterized by cyclic voltammetry, IR and ³¹P NMR spectroscopy.     

Comparison of blood rheological models for physiological flow simulation

The present study investigates the flow effects that different blood constitutive equations induce when employed in numerical simulations in the framework of computational hemodynamics. In accord with experimental studies on the rheological behavior of blood, three blood constitutive equations namely the Casson, Power-Law and Quemada models were used for simulating the shear flow behavior of blood. The case studied is the flow in a channel with a moving part of the boundary and was selected because it reproduces the flow phenomena occurring in realistic arterial conditions. Flow simulation for every model is carried out assuming the same flow rate at the inlet of the channel and different Strouhal numbers reflecting different intensities of the boundary movement. Results show that the modeling of blood as non-Newtonian fluid has marked qualitative and quantitative effects on both the flow field and the wall shear stress whereas comparison of the different models shows good agreement between the flow effects by the Casson and Quemada models.     

Genome-wide associations of gene expression variation in humans

The exploration of quantitative variation in human populations has become one of the major priorities for medical genetics. The successful identification of variants that contribute to complex traits is highly dependent on reliable assays and genetic maps. We have performed a genome-wide quantitative trait analysis of 630 genes in 60 unrelated Utah residents with ancestry from Northern and Western Europe using the publicly available phase I data of the International HapMap project. The genes are located in regions of the human genome with elevated functional annotation and disease interest including the ENCODE regions spanning 1% of the genome, Chromosome 21 and Chromosome 20q12–13.2. We apply three different methods of multiple test correction, including Bonferroni, false discovery rate, and permutations. For the 374 expressed genes, we find many regions with statistically significant association of single nucleotide polymorphisms (SNPs) with expression variation in lymphoblastoid cell lines after correcting for multiple tests. Based on our analyses, the signal proximal (cis-) to the genes of interest is more abundant and more stable than distal and trans across statistical methodologies. Our results suggest that regulatory polymorphism is widespread in the human genome and show that the 5-kb (phase I) HapMap has sufficient density to enable linkage disequilibrium mapping in humans. Such studies will significantly enhance our ability to annotate the non-coding part of the genome and interpret functional variation. In addition, we demonstrate that the HapMap cell lines themselves may serve as a useful resource for quantitative measurements at the cellular level.