Sucrose phosphate synthase activity and the co-ordination of carbon partitioning during sucrose and amino acid accumulation in desiccation-tolerant leaf material of the C4 resurrection plant Sporobolus stapfianus during dehydration.

Both sucrose and amino acids accumulate in desiccation-tolerant leaf material of the C(4) resurrection plant, Sporobolus stapfianus Gandoger (Poaceae). The present investigation was aimed at examining sucrose phosphate synthase (SPS) activity and various metabolic checkpoints involved in the co-ordination of carbon partitioning between these competing pathways during dehydration. In the initial phase of dehydration, photosynthesis and starch content declined to immeasurable levels, whilst significant increases in hexose sugars, sucrose, and amino acids were associated with concomitant significant increases in SPS and pyruvate kinase (PK) activities, and maximal activity levels of phosphoenolpyruvate carboxylase (PEPCase), NADP-dependent isocitrate dehydrogenase (NADP-ICDH), and NADH-dependent glutamate synthase (NADH-GOGAT). The next phase of dehydration was characterized by changes in metabolism coinciding with net hexose sugar phosphorylation. This phase was characterized by a further significant increase in sucrose accumulation, with increased rates of net sucrose accumulation and maximum rates of SPS activity measured under both saturating and limiting (inhibitory) conditions. SPS protein was also increased. The stronger competitive edge of SPS for carbon entering glycolysis during hexose phosphorylation was also demonstrated by the further decrease in respiration and the simultaneous, significant decline in both PEPCase and PK activities. A decreased anabolic demand for 2-oxoglutarate (2OG), which remained constant, was shown by the co-ordinated decrease in GOGAT. It is proposed that the further increase in amino acids in this phase of dehydration may be in part attributable to the breakdown of insoluble proteins

Amino acid pattern and glutamate metabolism during dehydration stress in the 'resurrection' plant Sporobolus stapfianus: a comparison between desiccation-sensitive and desiccation-tolerant leaves

The present study analyses changes in nitrogen compounds, amino acid composition, and glutamate metabolism in the resurrection plant Sporobolus stapfianus during dehydration stress. Results showed that older leaves (OL) were desiccation-sensitive whereas younger leaves (YL) were desiccation-tolerant. OL lost their soluble protein more rapidly, and to a larger extent than YL. Enzymes of primary nitrogen assimilation were affected by desiccation and the decrease in the glutamine synthetase (GS, EC 6.3.1.2) and ferredoxin-dependent GOGAT (Fd-GOGAT, EC 1.4.7.1) activities was higher in OL than in YL, thus suggesting higher sensibility to dehydration. Moreover, YL showed higher total GS enzyme activity at the end of the dehydration stress and was shown to maintain high chloroplastic GS protein content during the entire stress period. Free amino acid content increased in both YL and OL between 88% and 6% relative water content. Interestingly, OL and YL did not accumulate the same amino acids. OL accumulated large amounts of proline and gamma-aminobutyrate whereas YL preferentially accumulated asparagine and arginine. It is concluded (i) that modifications in the nitrogen and amino acid metabolism during dehydration stress were different depending on leaf development and (ii) that proline and gamma-aminobutyrate accumulation in S. stapfianus leaves were not essential for the acquisition of desiccation tolerance. On the contrary, the accumulation of large amounts of asparagine and arginine in the YL during dehydration could be important and serve as essential nitrogen and carbon reservoirs useful during rehydration. In this context, the role of GS for asparagine accumulation in YL is discussed

Valutazione della contaminazione da policlorobifenili (PCB) in terreni della Valbasento mediante GC-ECD con doppia colonna e GC-MS ad alta risoluzione

Comunicazione ORAL

Relationship between appetite levels and anxiety symptoms in chronic hemodialysis patients

Appetite level evaluated by the appetite and diet assessment tool (ADAT) is associated with several clinical and nutritional variables. Our aim was to expand the study to psychological variables (depression symptoms, anxiety symptoms, and distorted thinking). We studied 96 chronic kidney disease patients treated with hemodialysis three times per week. Representative variables are shown as median (percentile 25–percentile 75) or absolute values. DRI = daily recommended intake. Appetite level Very poor, poor (N=10) Fair, Good (N=31) Very Good (N=55) Tau Sex (F/M) 9 / 1 12 / 19* 22 / 33* -- Age (years) 65 (46–2) 50 (29–65) 47 (33–58)* −0.18& Creatinine (mg/dL) 7.4 (6.9–8.6) 11.1 (8.0–13.9)* 11.3 (9.4–13.0)* Kt/V 1.5 (1.3-1.6) 1.4 (1.2-1.5) 1.4(1.2-1.5) −0.03 Albumin (g/dL) 3.5 (3.3-3.9) 3.6 (3.5-3.8) 3.6 (3.5-3.8) 0.09 DRI (%) 78 (74–88) 88 (80–99)* 101 (99–103)* 0.54& Anxiety score 12 (12–20) 9 (4–16)* 5 (3–10)* –0.26 & ⁎ p < 0.05 versus poor or poor appetite, Mann-Whitney or chi2 test. & p < 0.05, correlation with appetite level (Kendall´s Tau coefficient) Very poor or poor appetite level was associated with female sex, older age, lower creatinine, lower DRI, and higher anxiety symptoms. Intervention of anxiety with cognitive behavioral therapy could improve nutritional treatment among vulnerable patients

Polychlorinated Biphenyls in Contaminated Soil Samples Evaluated by GC-ECD and GC-HRMS

We present and compare results obtained from the analy­sis of poly­chlorinated biphenyls (PCBs) of a limited number of contaminated soil samples collected in three areas of Basilicata region (south of Italy). The levels of PCBs were evaluated by using two analytical methods: (i) parallel dual-column gas-chromatography with dual electron capture detectors (GC–ECD) and (ii) gas-chromatography coupled to high-resolution mass spectrometry (GC–HRMS) via electron impact ionization (EI) in the multiple ion monitoring mode (MIM, two ions per compound). Two extraction methods prior to sample cleanup were also examined: microwave- assisted extraction (MAE) and ultrasonic- assisted extraction (UAE). The MAE was the extraction procedure adopted using acetone/ n-hexane (1:1, v/v) as it is mainly characterized by higher sample throughput and allowed reduced consumption of organic solvents. While extraction and analy­sis of spiked soil samples showed the applicability of both methods, systematic differences between the results were obtained for the sum of PCBs as a result of some non-detected congeners by GC–ECD compared with GC–HRMS. Indeed, high resolution MS using EI mode (electron energy 40 eV) with a resolving power of 10,000 provides additional information about the contamination pattern. The GC–ECD screening of 11 soil samples led to just one sample non-compliant to as it was close to the guide value for soils fixed by the Italian legislation (i.e., 60 ppb for private or urban soil). Using GC–HRMS, the amount of all PCBs found ranged from 5.4 to 127 ppb with five soil samples non-compliant to the guide value. The number of identified congeners ranged from 1 to 9 and 9 to 18 using dual-column GC–ECD and GC–HRMS, respectively

Laparoscopic Trainers and Surgical Virtual Simulators in Laparoscopic Learning Curve

Robotic Surgery is a current procedure in endosurgery, but literature has not addressed the learning curve for the use of the robotic assisted surgery. The learning curve for robot surgical procedures varies widely. Apart from innate skill, learning curves are composed of at least two fundamentals related to the volume of cases and the incidence rate. Commonly cited reasons include lack of adequate training in residency programs because of the time devoted to abdominal, vaginal, and obstetric procedures, lack of available and adequate training opportunities outside of dedicated fellowships, lack of proctors and mentor surgeons in communities to help to further advance the skills of younger surgeons, and lack of desire to leave established surgical practices to try to develop skills requiring long learning curves to master. Currently, the training involves practice with the surgical robot in either pig or human fresh tissue in a laboratory environment in order to become familiar with the functions of the robot, the attachment of the robotic arms to the robotic trocars, and the overall functions of the robotic console. In this chapter authors reviewed current literature on learning curve in robotic assisted surgery and screened problems linked to robotic surgical skills