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Speaking at the inaugural session of the World Future Energy Summit in Abu Dhabi, Chinese Prime Minister Wen Jiabao, was quoted as saying: ‘To stabilise the oil and natural gas market, we may consider establishing, under the G20 framework, a global energy market governance mechanism that involves energy suppliers, consumers and transit countries.’ (…) ‘We need to formulate …binding international rules through consultation and dialogue, and set up multilateral coordination mechanisms covering forecast and early warning, price coordination, financial regulation and emergency response.’ (emphasis added) On the same day, the Saudi Minister of Petroleum, Ali Naimi in an interview with CNN said: ‘Our wish and hope is we can stabilise this oil price and keep it at a level around $100 a barrel. If we were able as producers and consumers to average $100 I think the world economy would be in better shape.’ A few days later, the recently appointed Governor of SAMA – Saudi Arabia’s central bank – said that the Kingdom would offer excess oil production capacity if needed to balance oil prices, and that he expected prices to stay stable. It is then evident that the issue of price ‘stability’ remains very much a concern of major importers and exporters alike – notwithstanding that, relatively speaking, prices have been rather stable since the spring of 2009. This should be no surprise, because relative stability is explained by contingent circumstances, and may not last long. A structurally unstable market may well display temporary stability.

David Buchan assesses Europe’s collective ‘inaction’; and Giacomo Luciani focuses on the gas supply security issue.

‘Exporting countries, and more generally, the industry, have much to learn from oil developments in recent months. Lessons can be derived from an analysis of the causes of the oil price fall …’ Robert Mabro wrote this in 1998, and added: ‘An opportunity has now arisen for oil exporting countries, both from within and outside OPEC, to re-think the framework and substance of their co-operative policies. … The oil price crisis may prove deeper than initially thought and may remain immune for a while to the remedy which OPEC and other oil exporting countries are trying to apply.’ The ‘oil market’ – this difficult-to-define collective entity, which, through its collective ‘sentiment’ or ‘consensus’, determines the going prices for various contracts or ‘paper barrels’, which in turn conditions the prices of physical barrels – has an extraordinarily short memory. Several commentators have rushed to argue that today’s situation is different from that in 1985–6, and again from 1998, while in fact there is a simple common feature: there is too much oil in the market at prices that have for too long remained unreasonably high. The dynamics of the oil market are characterized by a succession of delusions and corrections. Trading in paper barrels feeds some widespread delusions – beliefs that cannot possibly withstand critical analysis, yet which come to be accepted as received wisdom. Such delusions are not promptly corrected in a market which – rather than moving towards an equilibrium of global demand and supply – allows profits to be made by those able to guess in which direction collective sentiment will go. As the price is driven further and further away from equilibrium by invented explanations, eventually reality catches up and a sharp correction ensues.

The paradox of the world’s foremost oil exporting country struggling to provide enough energy for itself is by now well known. On the face of it, it does not make much sense to spend time prioritizing alternative approaches: whether consumption should be reined in or alternative sources of electricity developed; or whether among the latter, priority should be given to renewables or nuclear. All of the above need to be pursued in parallel: hence my argument is not that nuclear power should be preferred to other solutions, but simply that it is likely to be part of the solution.

The stability under dynamic mechanical solicitation and with the temperature of the elastomagnetic composite made of Sm2Co7 particles embedded in a silicone matrix is investigated. The thermal stability was examined by DSC measurements. The thermal (up to congruent to 340 degrees C) and mechanical ageing effects on the material elastomagnetic response were investigated by measuring the amplitude, V-0, of the electromotive force induced in a pick-up coil during the dynamic mechanical solicitation of the sample. It was found that for the whole investigation range of temperatures, the V, dependence on the frequency, v, and amplitude, D, of the externally induced deformation is linear and its amplitude is not changing for treatments up to 150 degrees C; for higher temperature treatments the response amplitude is decreasing. The analysis of the response signal (registered at 1 h intervals) after dynamic mechanical solicitation carried out during 48 h, shows the excellent output reliability and no decrease in amplitude with time.

Previous investigations have shown that the signal transducers and activators of transcription (STATs) signaling pathway play an important role in the modulation of apoptosis after ischemia and reperfusion. The mechanism for this enhanced cardioprotection is unknown, but we believe that alterations STATs may play a role. To investigate this hypothesis, we examined the effects of angiotension II type 1 (AT1) and angiotension II type 2 (AT2) receptor antagonist added to cardioplegia on the downstream response of different STATs, connected with proinflammatory pathways (STAT2, STAT5) and prohypertrophic and antiapoptotic pathways (STAT3). Isolated, nonworking hearts (n = 3 per group) from neonatal rats were perfused aerobically (4°C) for 20 min in the Langendorff mode with the modified St. Thomas' Hospital no. 2 (MSTH2) cardioplegic solution (Group 1), the MSTH2 cardioplegic solution + AT1 receptor antagonist (Group 2), and MSTH2 cardioplegic solution + AT2 receptor antagonist (Group 3). Thus, myocytes were isolated by enzymatic digestion, and STAT2, STAT3, and STAT5 were investigated in Western blot studies. Times to arrest after cardioplegia were 8-12 s for all groups. Total cardioplegia delivery volume was about 300 mL for the 20 min. Perfusion with the MSTH2 cardioplegic solution supplemented with AT1 receptor antagonist (Group 2) induced a significant reduction in STAT2 and STAT5 tyrosine phosphorylation (-58 and -63%, respectively, vs. Group 1, P0.05). Conversely, STAT2 and STAT5 activation were unaffected by perfusion with the MSTH2 cardioplegic solution supplemented with AT2 receptor antagonist (Group 3). The decreased activation of STAT2 and STAT5 observed in Group 2 was accompanied by reduction of interleukin-1β (-57% in Group 2 vs. Group 1, P0.05). There were no significant differences in STAT3 phosphorylation among all groups. Only the addition of AT1 receptor antagonist to MSTH2 cardioplegia significantly decreases the inflammatory response of the neonatal rat cardiomyocytes without affecting antiapoptotic influence provided by tyrosine phosphorylation of STAT3. AT1 receptor antagonist added to cardioplegia represents an additional modality for enhancing myocardial protection during cardiac surgery and could contribute to optimize the ischemia tolerance of the pediatric heart.

Background: We aimed to evaluate the relationship between serum leptin and the leptin/body mass index (BMI) ratio with prevalent cardiovascular disease (CVD), and their influence on all-cause and CVD-related mortality in patients on hemodialysis (HD). Methods: 118 stable HD patients (50 women, median [interquartile range] age, 65.1 [54.7-72.2] years) were studied. All patients had baseline measurement of serum leptin concentrations. Relationships between leptin and all-cause and CVD mortality were studied by means of survival analysis and Cox regression analysis. Results: The leptin/BMI ratio was similar in patients with and without CVD at baseline (0.65 [0.29-2.23] vs. 0.68 [0.29-1.49] ng·m²/ml·kg, respectively, NS). Multiple logistic regression analysis showed that there was not an independent association between leptin/BMI ratio and prevalent CVD. During the follow-up time, 52 (44.1%) patients died. CVD was the cause of death in 27 out of 52 (51.9%) deceased patients. Survival analysis and Cox proportional multivariate regression analysis showed that there were no significant relationships between leptin levels or the leptin/BMI ratio and all-cause and CVD-related mortality. Conclusion: These results do not support that, in stable HD patients, serum leptin concentrations and the leptin/BMI ratio are related with prevalent CVD. Leptin/BMI ratio seems not to be a risk factor for mortality in these patients.

Background: We aimed to evaluate the relationship between serum leptin and the leptin/body mass index (BMI) ratio with prevalent cardiovascular disease (CVD), and their influence on all-cause and CVD-related mortality in patients on hemodialysis (HD). Methods: 118 stable HD patients (50 women, median [interquartile range] age, 65.1 [54.7-72.2] years) were studied. All patients had baseline measurement of serum leptin concentrations. Relationships between leptin and all-cause and CVD mortality were studied by means of survival analysis and Cox regression analysis. Results: The leptin/BMI ratio was similar in patients with and without CVD at baseline (0.65 [0.29-2.23] vs. 0.68 [0.29-1.49] ng·m²/ml·kg, respectively, NS). Multiple logistic regression analysis showed that there was not an independent association between leptin/BMI ratio and prevalent CVD. During the follow-up time, 52 (44.1%) patients died. CVD was the cause of death in 27 out of 52 (51.9%) deceased patients. Survival analysis and Cox proportional multivariate regression analysis showed that there were no significant relationships between leptin levels or the leptin/BMI ratio and all-cause and CVD-related mortality. Conclusion: These results do not support that, in stable HD patients, serum leptin concentrations and the leptin/BMI ratio are related with prevalent CVD. Leptin/BMI ratio seems not to be a risk factor for mortality in these patients. Introducción: El objetivo del presente estudio ha sido evaluar la relación entre la leptina sérica y el cociente leptina/índice de masa corporal (IMC) con la enfermedad cardiovascular (ECV) prevalente y su influencia en la mortalidad global y en la mortalidad por ECV en pacientes en hemodiálisis (HD). Métodos: Se estudiaron 118 pacientes estables en HD (50 mujeres, edad mediana [recorrido intercuartílico], 65,1 [54,7-72,2] años). En todos los pacientes se cuantificó la concentración basal de leptina. La relación entre leptina y la mortalidad se evaluó mediante análisis de supervivencia y análisis de regresión de Cox. Resultados: El cociente leptina/IMC fue similar en pacientes con y sin ECV prevalente (0,65 [0,29-2,23] frente a 0,68 [0,29-1,49] ng·m²/ml·kg, respectivamente, NS). El análisis de regresión logística mostró que no existía una asociación independiente entre el cociente leptina/IMC y la enfermedad cardiovascular prevalente. Durante el seguimiento 52 pacientes fallecieron (44,1%). La ECV fue causa de muerte en 27 de 52 pacientes fallecidos (51,9%). El análisis de supervivencia y el análisis multivariante de Cox mostraron que no hubo relación significativa entre los niveles de leptina o el cociente leptina/IMC y la mortalidad global o por causa de ECV. Conclusión: Estos resultados no apoyan la hipótesis de que, en pacientes estables en HD, las concentraciones de leptina y el cociente leptina/IMC estén relacionados con la ECV prevalente. Más aún, el cociente leptina/IMC no parece ser un factor de riesgo de mortalidad en estos pacientes.

Optimal surgical timing and operative technique in the treatment of acute cholecystitis are of major importance and are still debatable issues. We report the results of our study on the timing of surgery in a consecutive series of 163 patients treated in the emergency setting for acute cholecystitis over the period from 1998 to 2008. Early surgery and the partially downwards laparoscopic cholecystectomy technique provide a safe and effective way of treating these patients and preventing major complications. The mean time period between onset of symptoms and surgery was 69.2 hrs, with a median value of 53 hrs. The mean operative time was 63.9 min, with a conversion rate of 0.6% and a specific complication rate of 1.22%. The mean postoperative hospital stay was 3.2 days. The timing of surgery (measured in hours) and operative time (measured in minutes) were recorded and analysed to verify whether or not there was a statistically significant relationship between these two variables and establish the best timing for surgery. Our results show a linear relationship between operative time and the timing of surgery. Moreover, at the cut-off point of 57 hrs, the later subgroup (over 57 hrs) had a two-fold increase in operative time compared to the earlier subgroup. At more than 60 hrs approximately from the onset of symptoms, the pathological changes in the surgical target begin, with increasing rapidity, to present a troublesome challenge to the surgeon, making laparoscopic cholecystectomy for acute cholecystitis more difficult and less safe than when performed earlier.

Malnutrition is common in patients on hemodialysis and is a strong predicor of morbidity and mortality. Much progress has been made in recent years in identifying the causes and pathogenesis of malnutrition in hemodialysis patients as well as in recognizing the link between malnutrition and morbidity and mortality. Nevertheless, there is no consensus concerning its management. Conventional interventions such as nutritional counseling, oral nutritional supplements and intradialytic parenteral nutrition and novel preventive and therapeutic strategies such as appetite stimulants, growth hormone, androgenic anabolic steroids, and antiinflammatory drugs have been tested with contradictory and inconclusive results. Malnutrition still remains an important challenge for the nephrologist in the third millennium.

In the treatment of acute cholecystitis the optimal timing of operation, regardless of whether performed laparoscopically or conventionally, is of major importance and not yet well defined feature among the different authors. We report our study on the timing of surgery in a consecutive series of 133 patients.The surgical technique consists in a partially downwards cholecystectomy from the infundibulum to the cystic duct. The dissection never involves the Calot Triangle's structures; this provides a safe and effective way to prevent major complications procedure related. Length of time interval from the onset of symptoms to surgery (ST measured in hours) and operating time (OT measured in minutes) have been recorded and analyzed to find out how these two variables are each other linked and what is the best timing for surgery. We also split the series taking a progressively increasing of ST as a cut off point and analyzed the two derived subgroups to outline which was the time of surgery (period of ST) that provided the best result in term of worsening of laparoscopic procedure difficulty.51.3 hrs of average time between the onset of symptoms and surgery has been reported, with minimum of 24 hrs and maximum of 90 hrs, and median value of 48 hrs. The curve fit analysis on the scatterplot of the variable ST (independent) and OT (dependent) shows that these two variables are directly each other linked. The best division of the series was at the cut off of 57 hrs; each subgroup reached a statistical correlation coefficient: the late subgroup (the one over the cut off time of 57 hrs) had a twofold operating time increasing respect to the early group.Our results outline that there is a linear relationship between the technical difficulties, expressed in term of operating time, and time intervals from the onset of symptoms to surgery. At the cut off time of 57 hrs of interval from the onset of symptoms to surgery, the linear regression coefficient that links the dependent variable OT to the independent variable ST changes increasing up to 1,92. Over 60 hrs from the onset of symptoms the pathological changes of the surgical target becomes more and more quickly a troublesome challenge to the surgeon, letting the laparoscopic cholecystectomy for AC more difficult and less safe than that performed early.

Hemodiafiltration (HFR) with on-line regeneration of the ultrafiltrate, a technique of hemodiafiltration in which the ultrafiltrate passes through a cartridge containing uncoated charcoal, has been shown to be safe, simple, and well tolerated and has been claimed to improve nutritional status or to prevent its deterioration while decreasing the inflammatory response via a reduced production of proinflammatory cytokines. The purpose of the present prospective study was to ascertain whether HRF improves the nutritional status, reduces microinflammation, and decreases serum beta2-microglobulin levels in patients with end-stage renal disease (ESRD).Eight patients, four males and four females, with a mean age of 49.4 +/- 16.8 years, stable on hemodialysis over a period of 8.7 +/- 6.1 years and on standard 4-4.5 h three-times-a-week bicarbonate hemodialysis, were switched to three-times-a-week, 4-h HFR. At baseline and every two months for 12 months at mid-week, serum levels of urea, creatinine, albumin, total cholesterol, C-reactive protein, fibrinogen, complement, ferritin, beta2-microglobulin, intact parathyroid hormone (PTH), hemoglobin concentrations, and hematocrit and the EPO weekly dose were determined. At baseline and at the end of the study, the Malnutrition Inflammatory Score (MIS) was calculated.Nutritional and inflammatory parameters remained constant during the 12-month period of the study. After 12 months of HFR, the MIS trended to be lower, but the difference was not statistically significant. Serum beta2-microglobulin and PTH levels remained constant during all time intervals. Neither hematocrit nor hemoglobin changed over the course of the study as well as the weekly EPO dose.The change from bicarbonate hemodialysis to HFR was safe and well tolerated but was not associated with an improvement of nutritional and inflammatory parameters or a reduction of serum beta2-microglobulin levels.

The biomimetic method was used in order to deposit, on titanium substrates, an hydroxyapatite (HA) coating. The bioactive HA layer was obtained by using, in the first stage of the process, a glass having the composition 2.5CaO.2SiO(2) different from the one proposed for the application of the biomimetic method. This glass can be obtained via sol-gel, a method that allows one to obtain, easily, very pure products. The growth of HA crystals was confirmed by Fourier transform infrared, SEM, EDS and X-ray photoelectron spectroscopy (XPS) results. The experimental results suggest that, as reported in the literature for other supports, the silicate ions released from the glass in the first stage bind themselves to the titanium support. In particular, from XPS analysis it is evident that the titanium substrate is well covered by a calcium phosphate layer of the type of HA.

BACKGROUND: The use of interferon-alpha (IFN-alpha) to treat viral hepatitis C (HCV) occurring in kidney transplant recipients is controversial. This study reports an HCV patient successfully treated with IFN-alpha therapy achieving sustained response, negative serum HCV-mRNA and the disappearance of HCV antibodies, without impairment of renal function. METHOD: A young kidney transplant recipient developed a proven HCV infection 70 months post-transplantation. The patient received IFN-alpha therapy, and for a 32-month follow-up period was evaluated clinically, serologically and virologically. RESULTS: IFN-alpha therapy resulted in normal transaminase activities within 2 months. Serum HCV-mRNA was negative after 4 weeks of treatment and is still negative. Ten months after IFN-alpha therapy withdrawal, the enzyme immunoassay revealed that HCV antibodies (HCVAb) were absent in the serum. IFN-alpha therapy was safe, well tolerated and renal function was not impaired

Loss of lean body mass is frequently reported in patients with end-stage renal disease (ES-RD). Inadequate nutrient intake, superimposed illnesses, endocrine disorders, uremia and acidosis are some of the potential causes of muscle depletion. Previous reports on experimental models show that lean body mass depletion results from enhancement of muscle tissue protein catabolism, mainly associated with activation of ATP-ubiquitin-dependent proteolysis. Little is known, however, about the affects on this proteolytic system in ESRD patients on maintenance hemodialysis (HD). The present study was designed to investigate the expression of ubiquitin mRNAs in skeletal muscle of patients with ESRD on maintenance HD.Biopsies from the rectus abdominis muscle were obtained from eight ESRD patients and from six control subjects undergoing surgery for benign disease. Ubiquitin mRNA levels were measured by Northern blotting analysis.Patients with ESRD had mild metabolic acidosis, as a result of chronic intermittent HD. There were no significant differences between HD patients and controls with regard to the 1.2kb polyubiquitin mRNA species (332.9+/-139 vs 324.2+/-60; ns), but the levels of the 2.4 kb mRNA species were significantly lower in HD patients than in controls (1687+/-542 vs 2529.9+/-325, p=0.01). No correlation was observed between ubiquitin mRNA levels and nutritional parameters and degree of acidosis.The present study found that the ubiquitin mRNA levels were not increased in the muscle of stable, mildly acidotic hemodialysis patients.