Genetic relatedness among dioecious Ficus carica L. cultivars by random amplified polymorphic DNA analysis,and evaluation of agronomic and morphological characters

A collection of 64 fig (Ficus carica L.) accessions was characterized through the use of RAPD markers, and results were evaluated in conjunction with morphological and agronomical characters, in order to determine the genetic relatedness of genotypes with diverse geographic origin. The results indicate that fig cultivars have a rather narrow genetic base. Nevertheless, RAPD markers could detect enough polymorphism to differentiate even closely related genotypes (i.e., clones of the same cultivar) and a unique fingerprint for each of the genotypes studied was obtained. No wasteful duplications were found in the collection. Cluster analysis allowed the identification of groups in accordance with geographic origin, phenotypic data and pedigree. Taking into account the limited information concerning fig cultivar development, the results of this study, which provide information on the genetic relationships of genetically distinct material, dramatically increase the fundamental and practical value of the collection and represent an invaluable tool for fig germplasm management.     

Polyamines in the photosynthetic apparatus

The three main polyamines putrescine (Put), spermidine (Spd) and spermine (Spm) were characterized by HPLC in intact spinach leaf cells, intact chloroplasts, thylakoid membranes, Photosystem II membranes, the light-harvesting complex and the PS II complex. All contain the three polyamines in various ratios; the HPLC polyamine profiles of highly resolved PS II species (a Photosystem II core and the rection center) suggest an enrichment in the polyamine Spm.Abbreviations Chl chlorophyll - HPLC high performance liquid chromatography - LHC light-harvesting complex - PS II Photosystem II - PS II-RC Photosystem II reaction center - Put putrescine - Spd spermidine - Spm spermine - 10%S-core D₁-D₂-Cyt b559-47 kD-43 kD complex     

Ammonium-induced increase in NADH-glutamate dehydrogenase activity is caused by de-novo synthesis of the α-subunit

When callus derived from shoot segments of Vitis vinifera L. was transferred to ammonium-containing medium the aminating activity of NAD(H)-glutamate dehydrogenase (GDH, EC 1.4.1.2) increased significantly. This increase in enzyme activity closely paralleled an increase in the protein of the GDH -subunit (43.0 kDa), as detected by sodium dodecyl sulfate (SDS) gel electrophoresis and Western-blotting. A similar correlation was observed between the deaminating activity and the -subunit (42.5 kDa) which both decreased during this treatment. Using [³⁵S]methionine and immunochemical detection it was shown that the rate of synthesis of the -subunit increased considerably in the ammonium-containing medium while there was no detectable synthesis of the -subunit. At the isoenzyme level, ammonium caused an increase in the de-novo synthesis and hence the activity staining of the more anodic isoenzymes, which are hexameric and consist mainly of -subunits. The results indicate that the increase in NADH-GDH specific activity was due to de-novo synthesis of the -subunit of GDH and the assembly of only the more anodic isoenzymes.Abbreviations GDH glutamate dehydrogenase - PAGE polyacrylamide gel electrophoresis - SDS sodium dodecyl sulfate - TCA trichloroacetic acid     

The Generation of Active Oxygen Species Differs in Tobacco and Grapevine Mesophyll Protoplasts

Our previous results have shown that oxidative stress may reduce the regeneration potential of protoplasts, but only protoplasts that are able to supply extracellularly H(2)O(2) can actually divide (C.I. Siminis, A.K. Kanellis, K.A. Roubelakis-Angelakis [1993] Physiol Plant 87: 263-270; C.I. Siminis, A.K. Kanellis, K.A. Roubelakis-Angelakis [1994] Plant Physiol 1105: 1375-1383; A. de Marco, K.A. Roubelakis-Angelakis [1996a] Plant Physiol 110: 137-145; A. de Marco, K.A. Roubelakis-Angelakis [1996b] J Plant Physiol 149: 109-114). In the present study we have attempted to break down the oxidative burst response into the individual active oxygen species (AOS) superoxide (O(2)(*-)) and H(2)O(2), and into individual AOS-generating systems during the isolation of regenerating tobacco (Nicotiana tabacum L.) and non-regenerating grape (Vitis vinifera L. ) mesophyll protoplasts. Wounding leaf tissue or applying purified cellulase did not elicit AOS production. However, the application of non-purified cellulase during maceration induced a burst of O(2)(*-) and H(2)O(2) accumulation in tobacco leaf, while in grape significantly lower levels of both AOS accumulated. AOS were also generated when protoplasts isolated with purified cellulase were treated with non-purified cellulase. The response was rapid: after 5 min, AOS began to accumulate in the culture medium, with significant quantitative differences between the two species. In tobacco protoplasts and plasma membrane vesicles, two different AOS synthase activities were revealed, one that showed specificity to NADPH and sensitivity to diphenyleneiodonium (DPI) and was responsible for O(2)(*-) production, and a second NAD(P)H activity that was sensitive to KCN and NaN(3), contributing to the production of both AOS. The first activity probably corresponds to a mammalian-like NADPH oxidase and the second to a NAD(P)H oxidase-peroxidase. In grape, only one AOS-generating activity was detected, which corresponded to a NAD(P)H oxidase-peroxidase responsible for the generation of both AOS.     

Pituitary metastasis of follicular thyroid carcinoma

OBJECTIVE: The case of a 60-year-old male patient with follicular thyroid cancer who developed a pituitary mass proved to be a metastasis from thyroid cancer. METHODS: Assessment with whole-body scan, ultrasound, computed tomography and thyroglobulin measurements. RESULTS: Despite surgery and repeated doses of radioiodine, the patient developed diplopia and ptosis of the right eyelid, along with increasing thyroglobulin levels. A pituitary mass was discovered, with no signs of pituitary deficiency. The mass was removed and found to consist of neoplastic cells immunohistochemically positive to thyroglobulin. CONCLUSIONS: Distant metastases may develop in cases of follicular thyroid carcinoma, even after repeated doses of (131)I. Metastatic follicular thyroid carcinoma to the pituitary is a rare entity.     

Acute ST-segment elevation myocardial infarction after amoxycillin-induced anaphylactic shock in a young adult with normal coronary arteries: a case report

Background

Sirolimus-eluting stents (CYPHER stents) demonstrated remarkable efficacy in reducing restenosis rates in patients with coronary artery disease. There is a concern of sub-acute and late stent thrombosis. Tissue factor (TF) is critical in thrombosis. This study investigated the effect of sirolimus on TF expression and activity in cultured human vascular smooth muscle cells (SMCs).

Methods

SMCs were cultured from human saphenous veins and aortas. Quiescent cells were stimulated with sirolimus (0.1 – 20 ng/ml) over 24 hours. Cellular TF expression and activity released into culture medium were measured. The effect of sirolimus on activation of mammalian target of rapamycin (mTOR) was measured by phosphorylation of the substrate p70s6k at T389, and activation of RhoA was measured by pull-down assay.

Results

Sirolimus increased TF protein level in cultured human SMCs in a concentration and time-dependent manner (about 2-fold, p < 0.01) reaching maximal effect at 5 ng/ml. The stimulation of TF expression by sirolimus was associated with inhibition of basal activity of mTOR. No effects of sirolimus on RhoA or p38mapk activation that are positive regulators of TF in vascular wall cells were observed. The stimulation of TF expression by sirolimus (20 ng/ml) was prevented by the HMG-CoA reductase inhibitor fluvastatin (1 μmol/L). However, no increase in TF activity released from SMC into culture medium was observed after sirolimus treatment.

Conclusion

Although sirolimus stimulates TF protein expression in human SMC associated with inhibition of mTOR, it does not enhance TF activity released from the cells, suggesting a relatively safe profile of CYPHER stents. The inhibition of TF expression by fluvastatin favors clinical use of statins in patients undergoing coronary stenting.     

Accurate Prediction of Severe Allergic Reactions by a Small Set of Environmental Parameters (NDVI,Temperature)

Severe allergic reactions of unknown etiology,necessitating a hospital visit, have an important impact in the life of affected individuals and impose a major economic burden to societies. The prediction of clinically severe allergic reactions would be of great importance, but current attempts have been limited by the lack of a well-founded applicable methodology and the wide spatiotemporal distribution of allergic reactions. The valid prediction of severe allergies (and especially those needing hospital treatment) in a region, could alert health authorities and implicated individuals to take appropriate preemptive measures. In the present report we have collecterd visits for serious allergic reactions of unknown etiology from two major hospitals in the island of Crete, for two distinct time periods (validation and test sets). We have used the Normalized Difference Vegetation Index (NDVI), a satellite-based, freely available measurement, which is an indicator of live green vegetation at a given geographic area, and a set of meteorological data to develop a model capable of describing and predicting severe allergic reaction frequency. Our analysis has retained NDVI and temperature as accurate identifiers and predictors of increased hospital severe allergic reactions visits. Our approach may contribute towards the development of satellite-based modules, for the prediction of severe allergic reactions in specific, well-defined geographical areas. It could also probably be used for the prediction of other environment related diseases and conditions.     

In vitro and in vivo properties of distinct populations of amniotic fluid mesenchymal progenitor cells

Human mesenchymal progenitor cells (MPCs) are considered to be of great promise for use in tissue repair and regenerative medicine. MPCs represent multipotent adherent cells, able to give rise to multiple mesenchymal lineages such as osteoblasts, adipocytes or chondrocytes. Recently, we identified and characterized human second trimester amniotic fluid (AF) as a novel source of MPCs. Herein, we found that early colonies of AF-MPCs consisted of two morphologically distinct adherent cell types, termed as spindle-shaped (SS) and round-shaped (RS). A detailed analysis of these two populations showed that SS-AF-MPCs expressed CD90 antigen in a higher level and exhibited a greater proliferation and differentiation potential. To characterize better the molecular identity of these two populations, we have generated a comparative proteomic map of SS-AF-MPCs and RS-AF-MPCs, identifying 25 differentially expressed proteins and 10 proteins uniquely expressed in RS-AF-MPCs. Furthermore, SS-AF-MPCs exhibited significantly higher migration ability on extracellular matrices, such as fibronectin and laminin in vitro, compared to RS-AF-MPCs and thus we further evaluated SS-AF-MPCs for potential use as therapeutic tools in vivo. Therefore, we tested whether GFP-lentiviral transduced SS-AF-MPCs retained their stem cell identity, proliferation and differentiation potential. GFP-SS-AF-MPCs were then successfully delivered into immunosuppressed mice, distributed in different tissues and survived longterm in vivo. In summary, these results demonstrated that AF-MPCs consisted of at least two different MPC populations. In addition, SS-AF-MPCs, isolated based on their colony morphology and CD90 expression, represented the only MPC population that can be expanded easily in culture and used as an efficient tool for future in vivo therapeutic applications.     

VDR TaqI is associated with obesity in the Greek population

The prevalence of obesity has increased dramatically during the last thirty years in western countries with severe complications for health and economy. Obesity is the outcome of the strong interplay between genetic and environmental factors and is therefore widely expected that the discovery of the many genetic factors underlying the heritable risk of obesity will contribute critically to our basic knowledge of the disease etiopathogenesis and the identification of new targets for therapeutic intervention. The aim of the present study was to assess the genetic contribution of known polymorphisms in two genes that are linked to the pathogenetic mechanism of obesity. Analysis of vitamin D receptor (VDR) TaqI (rs731236; T/C) and fat mass and obesity-associated (FTO) (rs9930506; A/T) polymorphisms in 82 obesity subjects and 102 controls showed significant association for VDR TaqI ‘T’ allele and obesity (OR: 2.07; 1.123–3.816; P = 0.019), contributing to an elevated BMI of 3 kg/m² per risk allele. No association was observed for the FTO polymorphism. These results further support a role for VDR as risk factor for obesity and suggest its further validation in larger independent populations as well as highlight a target for functional analysis towards therapeutic intervention in obese individuals.