Current status and conservation of Pistacia germplasm

The genetic erosion of Pistacia germplasm has been highlighted in many reports. In order to emphasize this and to focus more attention on this subject, national and international (especially IPGRI and IFAR) institutions have initiated projects proposing to characterize, collect and conserve Pistacia germplasm. Therefore, this paper reviews recent research concerning conventional (in situ and ex situ) and unconventional biotechnological conservation strategies applied to the preservation of Pistacia germplasm. As regards conventional conservation, the majority of germplasm collections of Pistacia species are preserved on farms (in situ) and in seed and field genebanks (ex situ), as well as in the wild, where they are vulnerable to unexpected weather conditions and/or diseases. Hence, complementary successful unconventional in vitro methods (organogenesis, somatic embryogenesis and micrografting) and slow-growth storage conditions for medium-term preservation of Pistacia are presented together with the morphological and molecular studies carried out for the characterization of its species in this review. Moreover, special attention is additionally focused on cryopreservation (dehydration- and vitrification-based one-step freezing techniques) for the long-term preservation of Pistacia species. Possible basic principles concerning the establishment of a cryobank for the successful conservation of Pistacia germplasm are also discussed.     

Induction of embryogenic tissue and maturation of somatic embryos in Pinus brutia TEN

Embryogenic tissues (ET) of Turkish red pine (Pinus brutia TEN) were initiated from immature precotyledonary zygotic embryos sampled from 15 different plus trees. Seven collections were made weekly from June 10 to July 22, 2003. DCR basal medium supplemented with 13.6 μM 2,4–dichlorophenoxyacetic acid (2,4-D) and 2.2 μM benzylaminopurine (BAP) was used for initiation and maintenance of ET. Overall initiation frequency of ET in the study was 11.6%, initiation rates ranging between 4.7% and 24.1% per tree. Out of 12,940 explants tested, 3.4% were converted into established cell lines (ECL) following five subcultures. Of the maturation treatments tested, 80 μM ABA, sucrose (3%) and maltose (3% and 6%), and 3.75% PEG combined with 1% gellan gum were the most suitable combination for somatic embryo maturation.     

Preparation and characterization of UV-curable polymeric support for covalent immobilization of xylanase enzyme

The hydroxyl group of poly(ethylene glycol) monoacrylate (PEGMA) was activated by 1,1′-carbonyldiimidazole (CDI) and then a xylanase enzyme was immobilized to amine active PEGMA. UV-curable polymeric support formulation was prepared by mixing the xylanase bonded PEGMA, aliphatic polyester, 2-hydroxyethyl methacrylate (HEMA), poly(ethylene glycol) diacrylate (PEGDA) and photoinitiator. After UV irradiation, the enzymatic activity of the polymeric matrix was evaluated and compared with the corresponding free enzyme. By immobilization, the temperature resistance of the enzyme was improved and showed maximum activity at 60 °C. pH dependent activities of the free and immobilized enzymes were also investigated, and it was found that the pH of maximum activity for the free enzyme was 6.0, while for the optimal pH of the immobilized enzyme was 6.5. The immobilized enzyme retained 75% of its activity after 33 runs. The morphology of the polymeric support was characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) coupled with SEM was used to explore the chemical composition. The results have confirmed the evidence of enzyme in the structure of the polymeric material.     

In vitro conservation and cryopreservation of mature pistachio (Pistacia vera L.) germplasm

As genetic erosion of pistachio (Pistacia vera L.) has been occurring in the Mediterranean, Central and West Asia and North Africa, experiments were conducted to conserve two cultivars (‘Atl?’ and ‘Siirt’) of mature pistachio germplasm by assessing both medium- and long-term conservation techniques. In medium-term conservation, our results showed that it was feasible to conserve both cultivars in the form of either microshoots or encapsulated shoot apices up to 12 months at 4°C in the dark. As regards long-term conservation, encapsulation-dehydration and droplet-vitrification techniques were assessed for cryopreservation of cold-hardened and osmoprotected shoot apices of mature ‘Atl?’ cultivar. Among the methods tested, 13.6% of regrowth was achieved with incubation of explants in the droplets of vitrification solution for 150 min at 0°C followed by direct immersion in liquid nitrogen (LN), rapidly thawed and then cultured on Murashige and Skoog’s (MS) medium containing 1 mg L^?1 BA and 0.5 mg L^?1 GA_3. The developed droplet-vitrification technique appeared as a promising procedure for long-term preservation of shoot apices of mature pistachio germplasm. Moreover, assesment of genetic fidelity by Random Amplified Polymorphic DNA analysis (RAPD) revealed out high levels of genetic stability between donor plant and cryopreserved plants (similarity indexes between 0.959 and 0.973) after they were subcultured for at least 3 months. The detected low level of genetic instability could be due to the toxic effect of PVS2 and regeneration phase. The optimized conservation techniques, especially slow growth storage, could be applied to preserve other Pistacia species.     

Discovering functional interaction patterns in protein-protein interaction networks

Background  

In recent years, a considerable amount of research effort has been directed to the analysis of biological networks with the availability of genome-scale networks of genes and/or proteins of an increasing number of organisms. A protein-protein interaction (PPI) network is a particular biological network which represents physical interactions between pairs of proteins of an organism. Major research on PPI networks has focused on understanding the topological organization of PPI networks, evolution of PPI networks and identification of conserved subnetworks across different species, discovery of modules of interaction, use of PPI networks for functional annotation of uncharacterized proteins, and improvement of the accuracy of currently available networks.     

Tissue cryobanking for conservation programs: effect of tissue type and storage time after death

In this study, we investigated the temporal post-mortem limits, within which there will be guarantees of obtaining living cells from several tissues of sheep and cattle and the effect of vitrification on the ability of cells from tissue stored at different times. Muscle tissue and auricular cartilage were stored at 4°C for 5, 48, 72, 96 and 216 h post-mortem (hpm). Tissue samples were sorted into two groups: one group was in vitro cultured immediately after storage and the other was vitrified after storage and then in vitro cultured. In cattle and sheep, no differences in subconfluence rates were observed between the two experimental groups. At the same time, no significant differences were observed in the number of days required in culture to reach confluence between non-vitrified and vitrified groups when tissues were stored at 4°C for different times. In sheep, while the population doubling times (PDT) were similar in cartilage cells from vitrified and non-vitrified tissues and stored at 4°C for 5 and 216 hpm, PDT of muscle cells were longer in 216 hpm stored groups than in 5 hpm stored groups. In bovine, although the PDT of muscle cells were similar for 5 and 216 hpm and both vitrified and non-vitrified tissues and the PDT were longer in cartilage cells from vitrified than from non-vitrified tissues. In conclusion, although storage times and vitrification have different effects on tissues from cattle and sheep, this study showed that living cells could be obtained from all groups. Therefore, cartilage and muscle tissues can be stored at 4°C for 216 hpm and used for cyrobanking.     

Inhibition of tumor-associated human carbonic anhydrase isozymes IX and XII by a new class of substituted-phenylacetamido aromatic sulfonamides

Here, we investigate 28 structurally new sulfonamides and their subsequent testing for enzyme inhibition of cytosolic and tumor-associated carbonic anhydrases (CAs, EC 4.2.1.1). The compounds showed very potent inhibition of four physiologically relevant human (h) CA isoforms, namely hCA I, II, IX and XII. Interestingly, the K_I values were in the nanomolar range for the tumor-associated hCA IX and hCA XII. Docking studies have revealed details regarding the very favorable interactions between the scaffolds of this new class of inhibitors and the active sites of the investigated CA isoforms. As there are reported cases of tumors overexpressing both CA II and IX, such potent inhibitors for the two isoforms as those detected in this work, may have applications for targeting more than one CA present in tumors.     

Spectral analysis of photoplethysmographic signals: The importance of preprocessing

Heart rate variability (HRV) is an important and useful index to assess the responses of the autonomic nervous system (ANS). HRV analysis is performed using electrocardiography (ECG) or photoplethysmography (PPG) signals which are typically subject to noise and trends. Therefore, the elimination of these undesired conditions is very important to achieve reliable ANS activation results. The purpose of this study was to analyze and compare the effects of preprocessing on the spectral analysis of HRV signals obtained from PPG waveform. Preprocessing consists of two stages: filtering and detrending. The performance of linear Butterworth filter is compared with nonlinear weighted Myriad filter. After filtering, two different approaches, one based on least squares fitting and another on smoothness priors, were used to remove trends from the HRV signal. The results of two filtering and detrending methods were compared for spectral analysis accomplished using periodogram, Welch's periodogram and Burg's method. The performance of these methods is presented graphically and the importance of preprocessing clarified by comparing the results. Although both filters have almost the same performance in the results, the smoothness prior detrending approach was found more successful in removing trends that usually appear in the low frequency bands of PPG signals. In conclusion, the results showed that trends in PPG signals are altered during spectral analysis and must be removed prior to HRV analysis.     

Efficacy of marbofloxacin for naturally occurring contagious caprine pleuropneumonia

The aim of the present study is to determine the efficacy of marbofloxacin used in goats with naturally occurring contagious caprine pleuropneumonia (CCPP). The study was performed in two groups (consisting of 15 animals in each group) with two different doses of 10% aqueous solution of marbofloxacin injected intramuscularly into the semitendinous muscle. 2 mg/kg BW for 3 days (total dose administered: 6 mg/kg BW) was injected to the first group (group 1) and 3 mg/kg for 2 times every other day (total dose administered: 6 mg/kg BW) was injected to the second group (group 2). Microbiological analyses revealed that the causative agent of the disease was Mycoplasma capricolum subsp. capripneumoniae. Cure rates for groups 1 and 2 were determined as 100% (15/15 goats) and 93% (14/15 goats), respectively. The results of this field trial suggest that marbofloxacin could be an effective drug against CCPP in goats.