Electrosynthesis, physioelectrochemical and theoretical investigation of poly ortho aminophenol/magnetic functional graphene oxide nanocomposites as novel and hybrid electrodes for highly capacitive pseudocapacitors.

Magnetic functional graphene oxide (MFGO) has been synthesized in this work using FeCl4- magnetic anion paired with 1-methyl imidazolium cation. Hybrid poly ortho aminophenol (POAP)/MFGO films have then been prepared via POAP electropolymerization in the presence of MFGO nanosheets, serving as active electrodes for electrochemical supercapacitors. The FeCl4- functional group in MFGO plays a major part in atomic scale charge/energy transfer and consequently intramolecular electrochemical phenomena in MFGO systems, as shown by the theoretical results. POAP/MFGO composite films have been characterized by surface and electrochemical analyses. The performance of the system has been investigated by various electrochemical methods such as galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy. Novel nanocomposite compounds have been developed in this work for electrochemical redox capacitors. The advantages of these compounds include simple synthesis method, high active surface area and stability in aqueous electrolytes.

Recent insights into the biosynthesis and biological activities of natural xanthones.

This review focuses on recent advances in our understanding of the complex biosynthetic pathways and diverse biological activities of naturally occurring xanthones. The biosynthesis section covers studies published from 1989 to 2008 on xanthone production in plants and fungi, while the bioactivity review presents tabulated activities of more than 250 xanthones described in studies published from 2001 to 2008, together with structural information and indications of their wide-ranging potential uses as pharmacological tools. A large number of relevant papers have been published on these subjects (128 cited here), illustrating the diversity of the xanthones and their possible uses.

Characterization of fast pyrolysis bio-oils produced from pretreated pine wood.

The pretreatment of biomass prior to the fast pyrolysis process has been shown to alter the structure and chemical composition of biomass feed stocks leading to a change in the mechanism of biomass thermal decomposition. Pretreatment of feed stocks prior to fast pyrolysis provides an opportunity to produce bio-oils with varied chemical composition and physical properties. This provides the potential to vary bio-oil chemical and physical properties for specific applications. To determine the influence of biomass pretreatments on bio-oil produced during fast pyrolysis, we applied six chemical pretreatments: dilute phosphoric acid, dilute sulfuric acid, sodium hydroxide, calcium hydroxide, ammonium hydroxide, and hydrogen peroxide. Bio-oils were produced from untreated and pretreated 10-year old pine wood feed stocks in an auger reactor at 450 degrees C. The bio-oils' physical properties of pH, water content, acid value, density, viscosity, and heating value were measured. Mean molecular weights and polydispersity were determined by gel permeation chromatography. Chemical characteristics of the bio-oils were determined by gas chromatography-mass spectrometry and Fourier transform infrared techniques. Results showed that the physical and chemical characteristics of the bio-oils produced from pretreated pine wood feed stocks were influenced by the biomass pretreatments applied. These physical and chemical changes are compared and discussed in detail in the paper.

Prophylactic steroids for pediatric open heart surgery.

BACKGROUND: The immune response to cardiopulmonary bypass in infants and children can lead to a series of postoperative morbidities and mortality i.e. hemodynamic instability, increased infection and tachyarrhythmias. Administration of prophylactic doses of corticosteroids is sometimes used to try and ameliorate this pro-inflammatory response. However, the clinical benefits and harms of this type of intervention in the pediatric patient remains unclear. OBJECTIVES: To systematically review the beneficial and harmful effects of the prophylactic administration of corticosteroids, compared with placebo, in pediatric open heart surgery. SEARCH STRATEGY: The trials registry of the Cochrane Heart Group, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (Issue 4, 2006), MEDLINE (1966 to January 2007), EMBASE (1980 to January 2007) were searched. An additional handsearch of the EMRO database for Arabic literature was performed. Grey literature was searched and experts in the field were contacted for any unpublished material. No language restrictions were applied. SELECTION CRITERIA: All randomized and quasi-randomized controlled trials of open heart surgery in the pediatric population that received corticosteroids pre-, peri- or post-operatively, with reported clinical outcomes in terms of morbidity and mortality. DATA COLLECTION AND ANALYSIS: Eligible studies were abstracted and evaluated by two independent reviewers. All meta-analyses were completed using RevMan4.2.8. Weighted mean difference (WMD) was the primary summary statistic with data pooled using a random-effects model. MAIN RESULTS: All cause mortality could not be assessed as the data reports were incomplete. There was weak evidence in favor of prophylactic corticosteroid administration for reducing intensive care unit stay, peak core temperature and duration of ventilation [WMD (95% CI) -0.50 hours (-1.41 to 0.41); -0.20 degrees C (-1.16 to 0.77) and -0.63 hours (-4.02 to 2.75), respectively]. AUTHORS' CONCLUSIONS: The use of prophylactic steroids in pediatric patients to reduce postoperative complications commonly experienced following cardiopulmonary bypass surgery is not supported by the existing evidence. Further well designed and adequately powered randomized controlled trials are needed to more accurately estimate the benefit and harm of this intervention.

Post-portoenterostomy triangular cord sign prognostic value in biliary atresia: a prospective study.

The triangular cord sign (TC sign) is a sensitive and specific tool in prompt diagnosis of extrahepatic biliary atresia. The objective of this study is to evaluate post-operative TC sign presence in outcome prediction of infants with biliary atresia after Kasai hepato-portoenterostomy 27 infants and children with biliary atresia underwent 122 ultrasound examinations using both 5 MHz and 7 MHz convex linear transducers in 33 months follow up. For all infants TC sign identification was included pre-operatively, ultrasound was done 2 weeks post-operatively then bimonthly for 3 months, monthly for 2 months and every 3 months thereafter. 14 (53.8%) had post-operative TC sign. Once post-operatively positive, it remained positive throughout the study. It did not reappear in an initially post-operatively TC sign negative infant. Those having post-operative TC sign had statistically worse outcomes (0 became anicteric, 2 improved, 7 had progressive disease and 6 died) than those with a negative TC sign (p = 0.04) (3 became anicteric, 5 improved, 2 progressed and 1 died). Presence of TC sign post-operatively correlated with measure of removal of all fibrous cone at porta-hepatis during portoenterostomy (p = 0.026). Post-portoenterostomy TC sign is associated with more morbidity and mortality; and reflects inadequate surgical technique.

[Post-traumatic hypopituitarism after skull injury: apropos of 3 cases]. / Hypopituitarisme post-traumatisme crânien: à propos de trois cas.

BACKGROUND: Hypopituitarism is a rare but well-known complication of cranial trauma. In the absence of overt diabetes insipidus, its recognition is difficult as the onset of clinical symptoms can be very progressive, up to several years. CASE REPORTS: Three children, aged 8, 9 and 2 years, respectively, were admitted after a cranial trauma. Manifestations of diabetes insipidus occurred a few days later in two patients; one of them developed secondary growth hormone deficiency, hypothyroidism and hypogonadism, only evidenced at the age of 14 years. The third patient also developed manifestations of hypothalamic and/or pituitary hormone deficiencies without diabetes insipidus at the age of 12 years-6 months. MRI showed complete severance of the pituitary stalk in two patients and absence of posterior pituitary signal in one of the two patients with diabetes insipidus. CONCLUSION: Growth disorders and/or hypogonadism may occur many years after a trauma that may have been forgetten. Search for such an etiology and dynamic MRI are necessary in identifying heterogenous hypophyseal lesions.

Ten years of experience with patients with chronic active liver disease variceal bleeding: ablative versus selective decompressive therapy.

BACKGROUND: Variceal hemorrhage is an added major threat to survival in patients with chronic active liver disease (CALD). The hemodynamic consequences of surgical therapy and the continued activity of the underlying liver disease both contribute to the hepatic dysfunction and determine patient survival. METHODS: Two hundred and seventy two consecutive cases of (Child A or B) variceal bleeding with chronic hepatitis were surgically treated during a 10-year period. Histologic chronic active hepatitis (CAH) was documented in 160 (59%) patients, whereas chronic persistent hepatitis (CPH) was evident in 112 (41%). The applied surgical procedure was distal splenorenal shunt (DSRS) in 99 (36%) patients, splenectomy and gastroesophageal devascularization (SGD) in 108 (40%), and splenectomy with left gastric ligation (SLGL) in 65 (24%) patients. The preoperative data base obtained on these patients was matched comparing the three surgical modalities within each pathologic group (p > 0.05). RESULTS: The operative mortality was low among the patients with CAH (DSRS, 5.1%; SGD, 4.2%) with no deaths occurring in the CPH group. Among the individuals with CAH, recurrent variceal hemorrhage occurred significantly (p < 0.05) more often after SLGL (26%) and SGD (17%) than after DSRS (5%). Sclerotherapy rescued 93% (SGD) and 70% (SLGL) of the patients with rebleeding. DSRS significantly (p < 0.05) increased the risk of encephalopathy (28%) compared with SGD (4.2%) and SLGL (8%). The morbidity rates were quite low among the patients with CPH with no significant (p > 0.05) differences noted when the three surgical modalities were compared. Both groups experienced a significant (p < 0.05) increase in aspartate aminotransferase levels after the three procedures with a significant (p < 0.05) increase in bilirubin level occurring only after DSRS. The 5-year survival rate for the patients with variceal bleeding with CAH was 76% (DSRS), 73% (SGD), and 88% (SLGL). The leading causes of death were liver failure after DSRS (70%), variceal hemorrhage after SLGL (60%), and equally divided between septicemia (43%) and liver failure (43%) after SGD. The patients with CPH had a better 5-year survival of 89% (DSRS) and 100% (nonshunt operation). CONCLUSIONS: These data showed that (1) CALD is common among cases of variceal bleeding; (2) elective surgical treatment of variceal hemorrhage in patients with Child A or B CALD has a low operative mortality; (3) SLGL backed up by sclerotherapy is a better surgical alternative to either selective shunt or SGD in patients with active hepatitis, and (4) both DSRS and nonshunt operation are equally good surgical options for patients with CPH.

[Value of MRI in various forms of idiopathic growth hormone deficiency]. / Apports de l'IRM dans les diverses variétés de déficit idiopathique en hormone de croissance.

Magnetic resonance imaging (MRI) of the sellar and juxta sellar area was performed in 40 children with idiopathic hypopituitarism. MRI was normal in the 17 patients with partial growth hormone (GH) deficiency and in the 5 patients with GH neurosecretory dysfunction. Among the 18 patients with complete GH deficiency, the 10 with pituitary stalk transection presented more often with perinatal abnormalities, had the most severe GH deficiencies and more frequently multiple hormone deficiencies, in particular TSH deficiency. Pituitary gland size studies showed that the small size of the residual glandular tissue was responsible for these particularities. If MRI is of no great interest for functional GH deficiency, in half of the primary complete GH deficiencies, it enables to visualize a pituitary stalk transection with regeneration of neurohypophysis.

Should both schistosomal and nonschistosomal variceal bleeders be disconnected?

Splenopancreatic disconnection (SPD) was conceived and implemented as a technical addition to distal splenorenal shunt (DSRS) to maintain its selectivity and preserve portal perfusion. The proposed hemodynamic and metabolic stability of hepatocytes after DSRS-SPD should improve survival. In this nonrandomized study, 145 consecutive (Child A/B) variceal bleeders were electively subjected to selective shunt with DSRS in 93 and DSRS-SPD in 52 patients. The 2 groups were similar before surgery with a mean follow up of 24 +/- 12 (DSRS) and 27 +/- 14 (DSRS-SPD) months. DSRS-SPD had an operative mortality of 3.8%. Postoperative pancreatitis occurred in 7.7% after DSRS-SPD and 3.2% after DSRS alone, with schistosomal hepatic fibrosis representing 86% of morbid cases. Shunt patency was high and recurrent variceal hemorrhage was low in both groups. Clinical encephalopathy was significantly reduced after DSRS-SPD (p less than 0.05). The addition of SPD significantly reduced both the incidence of chronic hyperbilirubinemia in the schistosomal patients (p less than 0.05) and the difference between the changes in total serum bilirubin in all patients (p = 0.001). Portal perfusion was preserved after DSRS-SPD in all of the angiographically-studied patients. The overall survival was 84% after DSRS and 88% after DSRS-SPD. The schistosomal patients showed an incidence of 95% and 96% survival after DSRS and DSRS-SPD, respectively. DSRS-SPD was able to improve survival (92%) better than DSRS (77%) among well-matched nonschistosomal patients. These data show: (1) DSRS-SPD still has low operative mortality and a high patency rate with a low incidence of recurrent variceal hemorrhage, (2) DSRS-SPD maintains portal perfusion, achieves better survival, and reduces the incidence of encephalopathy, especially in patients with nonalcoholic cirrhosis and mixed liver disease, (3) in the schistosomal population, DSRS-SPD reduces the incidence of chronic hyperbilirubinemia but increases the risk of postoperative pancreatitis.

Selective shunt versus nonshunt surgery for management of both schistosomal and nonschistosomal variceal bleeders.

This clinical study included 219 (Child A/B) consecutive variceal bleeders. Electively 123 had distal splenorenal shunt (DSRS) and 96 had splenectomy with gastroesophageal devascularization (S&GD). Liver pathology was documented in 73% of patients, with schistosomal fibrosis in 41% and nonalcoholic cirrhosis or mixed pattern (fibrosis and cirrhosis) in 59%. The surgical groups were similar before operation, with a mean follow-up of 82 +/- 13 and 78 +/- 18 months, respectively (range, 60 to 120 months). The two pathologic populations were also similar before each and both procedures. The operative mortality rates were low, with incidences of 3.3% (DSRS) and 3.1% (S&GD). Rebleeding occurred significantly (p less than 0.05) more frequently after S&GD (27%) compared to DSRS (5.7%). Sclerotherapy salvaged 65% of S&GD rebleeders. Encephalopathy developed significantly (p less than 0.05) more after DSRS (18.7%) compared to S&GD (7.3%), with no significant difference among the current survivors. The difference in overall rebleeding and encephalopathy rates between both procedures was statistically related to patients with cirrhosis and mixed lesions (p less than 0.05). Distal splenorenal shunt significantly reduced the endoscopic variceal size more than S&GD (p less than 0.05). Prograde portal perfusion was documented in 94% of patients in each group, with a variable distinct pattern of portaprival collaterals in 91% (DSRS) and 65% (S&GD). The total population cumulative survival was similar with 80% for DSRS and 79% for S&GD (plus sclerosis in 23%), with hepatic cell failure the cause of death in 46% and 50%, respectively. However, in the schistosomal patients, survival was better improved after DSRS (90%) compared to S&GD (75%), with no difference among the cirrhotic and mixed group (DSRS 73%, S&GD 72%). In conclusion (1) both DSRS and S&GD have low operative mortality rates, (2) DSRS is superior to S&GD in the schistosomal patients, and (3) S&GD backed by endosclerosis for rebleeding is a good surgical alternative to selective shunt in the nonalcoholic cirrhotic and mixed population.

Schistosomal versus nonschistosomal variceal bleeders. Do they respond differently to selective shunt (DSRS)?

The distal splenorenal shunt (DSRS) was performed in 125 consecutive variceal bleeders. To date, no patients have been lost to follow-up (mean of 79 +/- 20 months). Liver pathology was documented in 85 patients: 45 patients had schistosomal hepatic fibrosis, 17 had nonalcoholic cirrhosis, and 23 had mixed pattern (hepatic fibrosis and cirrhosis). The preoperative data base for these three groups was matched (p greater than 0.05), with a mean follow-up of 79 +/- 20, 70 +/- 14, and 77 +/- 22 months for each population, respectively. The results showed low operative mortality (4.8%), high cumulative patency rate (94.8%) and low recurrent variceal hemorrhage (5.6%). The biochemical data showed significant increase in serum bilirubin (p less than 0.001) and aspartate transaminase (AST) (p less than 0.05) in the nonschistosomal patients. Chronic hyperbilirubinemia was found in 33% of the schistosomal group. Prograde portal perfusion was detected in 94% of the patients, with development of collaterals in 91%. The angiographic pattern of these collaterals was 50% pancreatic, 45% gastric, and 26% colosplenic. Patients with mixed liver disease had a high incidence of Grade III portal perfusion (57%) and more common pancreatic and gastric collaterals (71%). The cumulative survival for all patients was 74.1%, with hepatic cell failure being the leading cause of death (13 patients, 50% of all deaths). The schistosomal patients had a 91.6% incidence, whereas the cirrhotic and mixed groups had survival rates of 75.6% and 65.2%, respectively. Also, of a 15% total incidence of encephalopathy, 4.4% was related to the schistosomal patients, 23.5% to the cirrhotics, and 21.7% to the mixed population. Statistically, the survival rate was significantly better (p less than 0.05) and encephalopathy was significantly lower (p less than 0.05) in the schistosomal population. In conclusion, this data shows that: 1) DSRS has a high patency rate and a low variceal hemorrhage recurrence rate; 2) it maintains some degree of portal perfusion in patients with different nonalcoholic liver diseases, despite development of collaterals; and 3) the schistosomal patients have a better survival rate, with a low incidence of encephalopathy after DSRS, compared with the cirrhotic and mixed populations.

Distal splenorenal shunt for management of variceal bleeding in patients with schistosomal hepatic fibrosis.

The distal splenorenal shunt was performed in 60 patients with schistosomal hepatic fibrosis in whom no evidence of cirrhosis was documented by preoperative needle and operative wedge biopsy. No patients have been lost to follow-up with a median of 37 months (range: 17-86). The results showed low operative mortality (1.7%), high patency rate (92.5%), and low recurrent variceal hemorrhage (6.7%). Thrombosed shunts were treated either by refashioning the shunt (1 patient) or splenectomy and gastric devascularization (2 patients). Initial hyperbilirubinemia and reduction in serum albumin were found in the early postoperative period, with persistent hyperbilirubinemia in 32% of the patients. The 5-year survival was 88%, with liver disease related mortality in only three patients. Clinical encephalopathy was detected in three patients (5.1%); only one of them was incapacitated. These data showed that: selective shunt (distal splenorenal shunt, DSRS) is an effective surgical procedure in the treatment of schistosomal variceal bleeding, shunt thrombosis is rare and can possible be corrected if detected early, schistosomal patients have a better survival and a lower incidence of encephalopathy after DSRS than that reported in cirrhotics, and liver biopsy should be performed for proper assessment of the schistosomal population especially in the geographic areas where the schistosoma parasite and viral hepatitis are endemic.