Remarkably enhanced direct dissolution of plutonium oxide in task-specific ionic liquid: insights from electrochemical and theoretical investigations.

The present work envisages an approach for direct dissolution of PuO2 in a task-specific ionic liquid (TSIL). An attractive possibility to electrodeposit plutonium from the mixture of TSIL and PuO2 has been explored further. The carboxyl functional group attached to the TSIL plays a key role in facilitating the dissolution of plutonium ions.

Selective recognition of uranyl ions from bulk of thorium(iv) and lanthanide(iii) ions by tetraalkyl urea: a combined experimental and quantum chemical study.

The selective separation of uranyl ions from an aqueous solution is one of the most important criteria for sustainable nuclear energy production. We report herein a known, but unexplored extractant, tetraalkyl urea, which shows supreme selectivity for uranium in the presence of interfering thorium and other lanthanide ions from a nitric acid medium. The structural characterization of the uranyl complex (UO2X2·2L, where X = NO3(-), Cl(-) and Br(-)) by IR, NMR and single crystal X-ray diffraction provides insight into the strong interaction between the uranyl ion and the ligand. The origin of this supreme selectivity for uranyl ions is further supported by electronic structure calculations. Uranyl binding with the extractant is thermodynamically more favourable when compared to thorium and the selectivity is achieved through a combination of electronic and steric effects.

Assessment of metal enrichment and their bioavailability in sediment and bioaccumulation by mangrove plant pneumatophores in a tropical (Zuari) estuary, west coast of India.

Sediment collected from the estuarine mangroves of the Zuari estuary and Cumbharjua canal were analyzed to assess the concentration, contamination and bioavailability of metals. Mangrove pneumatophores were also analyzed to understand the metal bioaccumulation in mangrove plants. The results indicated the variation of metal concentrations in sediment along the estuary was attributed to changing hydrodynamic conditions, type of sediment and metal sources. Further, speciation studies revealed that Fe, Cr, Co, Ni, Cu and Zn were mainly of lithogenic origin and less bioavailable while high Mn content in the sediment raised concerns over its potential mobility, bioavailability and subsequent toxicity. The mangrove plants exhibited difference in metal accumulation due to variations in sediment parameters and metal availability, in addition to difference in plant species and tissue physiology that affect metal uptake. Moreover, the mangrove plants reflected the quality of the underlying sediment and can be used as a potential bio-indicator tool.

Effects of early life interventions and palatable diet on anxiety and on oxidative stress in young rats.

Early life events can change biochemical, endocrine and behavioral aspects throughout the life of an animal. Since there is a strong relationship between stress, neonatal handling and feeding behavior, the aim of this study was to investigate the effects of these three factors on behavioral parameters (anxiety and locomotion), oxidative stress in brain structures (prefrontal cortex and hippocampus) and on plasma glucose. Nests of Wistar rats were handled (10 min/day), or not (control groups), on days 1-10 after birth. Males from these groups were divided into 4 subgroups: (1) stressed by isolation in childhood (pre-puberty) and with access to a highly palatable diet (2) stressed by isolation and receiving standard lab chow (3) not isolated and receiving a highly palatable diet and (4) not isolated and receiving standard chow. The animals were kept under these conditions for 7 days. Rats receiving the highly palatable diet consumed more food, more calories, gained more weight and had a higher plasma glucose level, but had a lower caloric efficiency than the standard chow groups. Both handling and palatable diet were able to increase food consumption on the first day of isolation. Isolation stress had an anxiogenic effect in the plus maze, which was counteracted by handling. Palatable diet increased time spent in the central area of the open field apparatus and in the open arms of the elevated plus maze, showing an anxiolytic effect. The use of both these conditions, however, does not appear to bring additional protection against the effects of stress during this particular period of life, i.e., pre-puberty. In the prefrontal cortex, handling reduced thiol content and appears to imbalance the antioxidant enzymes system, which is counteracted by a palatable diet. Hippocampus seems to be more sensitive than the prefrontal cortex to early interventions, especially to the highly palatable diet, and both handling and diet appear to imbalance the antioxidant enzyme system. Thus, measurements of antioxidant enzymes activities indicate that handling may endanger some brain structures and that the palatable diet was able to prevent some handling effects on antioxidant enzymes, depending on the brain structure.

Experience of malignancies with oral glucose-lowering drugs in the randomised controlled ADOPT (A Diabetes Outcome Progression Trial) and RECORD (Rosiglitazone Evaluated for Cardiovascular Outcomes and Regulation of Glycaemia in Diabetes) clinical trials.

AIMS/HYPOTHESIS: Observational and mechanistic studies have suggested a possible relationship between treatment with metformin and decreased incidence of cancer in participants with type 2 diabetes. We extracted data for malignancies from the ADOPT (A Diabetes Outcome Progression Trial) and RECORD (Rosiglitazone Evaluated for Cardiovascular Outcomes and Regulation of Glycaemia in Diabetes) randomised controlled clinical trials, in which the efficacy and/or safety of metformin was assessed in comparison with sulfonylureas and rosiglitazone. METHODS: Neoplasm occurrences were collected as adverse events in these studies. We reviewed and re-analysed the individual participant data in both studies for serious adverse events, malignancies reported as adverse events and related neoplasms of special interest. RESULTS: In ADOPT, 50 participants (3.4%) on metformin and 55 (3.8%) on each of rosiglitazone and glibenclamide (known as glyburide in the USA and Canada) developed serious adverse event malignancies (excluding non-melanoma skin cancers). This corresponds to 1.03, 1.12 and 1.31 per 100 person-years, giving hazard ratios for metformin of 0.92 (95% CI 0.63-1.35) vs rosiglitazone and 0.78 (0.53-1.14) vs glibenclamide. In RECORD, on a background of sulfonylurea, 69 (6.1%) participants developed malignant neoplasms in the metformin group, compared with 56 (5.1%) in the rosiglitazone group (HR 1.22 [0.86-1.74]). On a background of metformin, 74 (6.7%) participants in the sulfonylurea group developed malignant neoplasms, compared with 57 (5.1%) in the rosiglitazone group (HR 1.33 [0.94-1.88]). CONCLUSIONS/INTERPRETATION: The malignancy rates in these two randomised controlled clinical trials do not support a view that metformin offers any particular protection against malignancy compared with rosiglitazone. However, they do not refute the possibility of a difference compared with sulfonylureas.

Remifentanil and fentanyl during anaesthesia for major abdominal and gynaecological surgery. An open, comparative study of safety and efficacy.

BACKGROUND: and objective This open, multicentre study compared the efficacy and safety of remifentanil with fentanyl during balanced anaesthesia with 0.8% isoflurane (end-tidal concentration) for major abdominal and gynaecological surgery, and the efficacy and safety of remifentanil for pain management in the immediate postoperative period. METHODS: Two-hundred and eighty-six patients were randomized to receive remifentanil 1 microg kg(-1) followed by 0.2 microg kg(-1) min-1 (n=98), remifentanil 2 microg kg(-1) followed by 0.4 microg kg(-1) min(-1) (n=91) or fentanyl 3 microg kg(-1) (n=97) at induction. Thereafter, the study opioids and isoflurane were titrated to effect during the operation. RESULTS: Compared with fentanyl, remifentanil 2 microg kg(-1) followed by 0.4 microg kg(-1) min(-1) reduced the incidence of response to tracheal intubation (30% vs. 13%, P < 0.01), skin incision (33% vs. 4%, P < 0.001) and skin closure (11% vs. 3%, P < 0.05), respectively. Patients receiving remifentanil 1 microg kg(-1) followed by 0.2 microg kg(-1) min(-1) had fewer responses to skin incision than the fentanyl group (12% vs. 33%, P < 0.001), but the incidences of response to tracheal intubation and skin closure were similar. Significantly fewer patients in both remifentanil groups had > or = 1 responses to surgical stress intraoperatively compared with fentanyl (68% and 48% vs. 87%, P < 0.003). The mean isoflurane concentrations required were less in both remifentanil groups compared with the fentanyl group (0.1%, P=0.05). In remifentanil-treated patients, continuation of the infusion at 0.1 microg kg(-1) min(-1) with titration increments of +/- 0.025 microg kg(-1) min(-1) was effective for the management of immediate postoperative pain prior to transfer to morphine analgesia. However, a high proportion of patients experienced at least moderate pain whilst the titration took place. CONCLUSIONS: Anaesthesia combining isoflurane with a continuous infusion of remifentanil was significantly more effective than fentanyl at blunting responses to surgical stimuli. Significantly fewer patients responded to tracheal intubation with remifentanil at 0.4 microg kg(-1) min(-1), supporting the use of a higher initial infusion rate before intubation. Both remifentanil and fentanyl were well-tolerated, with reported adverse events typical of mu-opioid agonists.

Worm burdens in outbred and inbred laboratory rats with morphometric data on Syphacia muris (Yamaguti, 1935) Yamaguti, 1941 (Nematoda, Oxyuroidea).

Syphacia muris worm burdens were evaluated in the rat Rattus norvegicus of the strains Wistar (outbred), Low/M and AM/2/Torr (inbred), maintained conventionally in institutional animal houses in Brazil. Morphometrics and illustration data for S. muris recovered from Brazilian laboratory rats are provided for the first time since its proposition in 1935.

Helminth fauna of the golden hamster Mesocricetus auratus in Brazil.

Helminth fauna of conventionally maintained hamsters from institutional animal houses that supply the research community with laboratory animals and from an openly kept control group, randomly purchased in a pet shop in the State of Rio de Janeiro, were evaluated and compared. Necropsied animals from institutional suppliers were infected with the oxyurid nematodes Syphacia criceti and S. mesocriceti and with the cestode Rodentolepis nana; those from the pet shop were infected with S. mesocriceti and R. nana. These are the first morphometric data that are based on Brazilian samples of these species parasitizing hamsters. Mesocricetus auratus is a newly recorded host for S. criceti, previously recovered from Oryzomys subflavus and Calomys callosus in Brazil. The potential of pet and laboratory hamsters in the spreading of helminth infections to humans is also considered.

Description of males of Parabronema pecariae Ivaschkin, 1960 (Nematoda, Habronematoidea) parasitizing peccaries (Mammalia, Tayassuidae) in Brazil.

Nematodes studied herein and identified as Parabronema pecariae were collected in 1936 in the States of Rio de Janeiro and Pará and in 1940 in the State of Mato Grosso do Sul, Brazil. This species was proposed, with basis on female specimens that had been described earlier as Parabronema sp. Although the presence of males of P. pecariae was previously reported in Brazil, their description was not provided. The present paper deals with the first complete morphometric data on male specimens of P. pecariae recovered from peccaries (Pecari tajacu and Tayassu pecari).

On two nematodes from Brazilian birds and description of a new species (Acuarioidea, Schistorophinae) parasitizing Laterallus viridis (Müller, 1776) (Gruiformes, Rallidae).

The present paper reports acuarioid nematodes recovered from avian hosts. A new species of the genus Schistorophus Railliet, 1916 is proposed based mainly on findings referring to ptilina, spicules and vagina. Ancyracanthopsis coronata (Molin, 1860) Chabaud & Petter, 1959 is referred again in Brazil since its proposition in 1860, from specimens recovered from a Brazilian bird. A revised key to the species of the genus Schistorophus is also presented.

The safety and effectiveness of remifentanil as an adjunct sedative for regional anesthesia.

UNLABELLED: We assessed the sedative potential of continuous infusions of remifentanil with a validated composite alertness scale in 160 patients (ASA physical status I or II) undergoing hip replacement surgery with spinal block (n = 61) or hand surgery using brachial plexus block (n = 93). They were randomized to receive one of the following initial dose regimens in double-blinded fashion: placebo or 0.04, 0.07, or 0.1 microg x kg(-1) x min(-1) remifentanil subsequently titrated to effect. Additional midazolam IV was allowed for adequate sedation as required. The combined analysis of both surgery groups revealed a dose-related increase in achievement of sedation level > or =2 within 15 min of the start of the study drug infusion; all remifentanil dose comparisons with placebo reached significance (P < 0.001). The remifentanil 50% effective dose for a composite sedation level > or =2 within 15 min of the start of drug infusion was estimated as 0.043 microg x kg(-1) x min(-1) (95% confidence interval 0.01, 0.059). The requirement for midazolam decreased with increasing remifentanil dose compared with placebo (P < 0.001). The median time to return to alertness after the end of infusion was 10-12 min in the remifentanil groups and 5 min in the placebo group. Significant incidences of nausea, pruritus, sweating, and respiratory depression were reported during remifentanil infusions compared with placebo. The data suggest that remifentanil may be useful for supplementation of regional anesthesia, provided that ventilation is carefully monitored. IMPLICATIONS: In this dose-finding, placebo-controlled study, remifentanil infusions were used to provide sedation during spinal and brachial plexus regional anesthesia. The 50% effective dose for achievement of sedation was 0.043 microg x kg(-1) x min(-1). Return to alertness occurred after 10-12 min (median time). Remifentanil infusions can be used to supplement regional anesthesia, but this requires careful monitoring of ventilation.

Helminth parasites of conventionally maintained laboratory mice--II. Inbred strains with an adaptation of the anal swab technique.

Worm burdens recovered from inbred mice strains, namely C57Bl/6, C57Bl/10, CBA, BALB/c, DBA/2 and C3H/He, conventionally maintained in two institutional animal houses in the State of Rio de Janeiro, RJ, Brazil, were analyzed and compared, regarding their prevalences and mean intensities. Three parasite species were observed: the nematodes Aspiculuris tetraptera, Syphacia obvelata and the cestode Vampirolepis nana. A modification of the anal swab technique is also proposed for the first time as an auxiliary tool for the detection of oxyurid eggs in mice.

[Aneurysms of the interatrial septum]. / Aneurismas do septo interauricular.

Atrial septum aneurysms are an uncommon condition, underestimated before the routine use of echocardiography. Their clinical importance has increased after being associated with thromboembolic events. The authors made a review of clinical, diagnostic and therapeutic features of this entity after reporting six clinical cases.

A randomized, blind comparison of remifentanil and alfentanil during anesthesia for outpatient surgery.

UNLABELLED: We compared remifentanil, an esterase-metabolized opioid, with alfentanil as part of balanced anesthesia with at least 0.8% isoflurane during outpatient surgery in a randomized, double-blind trial. One hundred two patients received remifentanil, and 99 patients received alfentanil. Patients who received remifentanil experienced significantly fewer stress responses to surgical stimuli (52.9% and 65.7%, P < 0.05); significantly fewer remifentanil patients responded to skin closure (11% and 22%, P < 0.05) than patients who received alfentanil. Significantly more patients in the alfentanil group required extra analgesia compared with the remifentanil group (P < 0.05). Time to respond to verbal command was shorter for alfentanil than remifentanil (median 7 min vs 9 min), and times to spontaneous respiration (median 5 min vs 8 min), adequate respiratory rate (median 6 min vs 9 min), and tracheal extubation (median 6 min vs 9 min) were significantly shorter for alfentanil in comparison with remifentanil (P < 0.05). Remifentanil patients, however, showed significantly better recovery of psychomotor and psychometric function between 30 and 90 min after surgery (P < 0.05). The incidences of hypotension intraoperatively and shivering postoperatively were significantly higher with remifentanil. No unexpected or serious adverse events were recorded with remifentanil; however, one patient who received alfentanil experienced severe recurrent respiratory depression after surgery. The metabolic profile of remifentanil allowed better intraoperative analgesia without compromising recovery. IMPLICATIONS: The pharmacological profile of remifentanil, a new opioid for use in anesthesia, suggests that rapid recovery will occur after its use. This study of 200 outpatients shows that the differences suggested from kinetic studies are not always borne out in clinical practice, although later recovery variables did, in fact, favor remifentanil.

A comparison of remifentanil and alfentanil in patients undergoing major abdominal surgery.

The efficacy and safety of remifentanil and alfentanil for patients undergoing major abdominal surgery were compared. Premedicated patients received a loading dose of remifentanil (1.0 microgram.kg-1; n = 116) and a continuous infusion of 0.5 microgram.kg-1.min-1, or a loading dose of alfentanil (25 micrograms.kg-1; n = 118) and a continuous infusion of 1.0 microgram.kg-1.min-1. Propofol was administered (10 mg every 10 s) until loss of consciousness. Patients' lungs were ventilated with 66% nitrous oxide and 0.5% (end-tidal) isoflurane in oxygen. The study drug infusion rate was reduced by 50% 5 min after intubation. Alfentanil was discontinued 15 min before the end of surgery, whereas remifentanil was continued in the immediate postoperative period at a reduced dose. Responses to intubation (28%) and skin incision (17%) occurred approximately twice as often in the alfentanil group (15% and 8%; p = 0.014 and p = 0.037, respectively). More patients receiving alfentanil had one or more responses to surgery (72% vs. 57%; p = 0.016). The time to spontaneous respiration, adequate respiration, response to verbal command and time to recovery room discharge were similar. However, owing to decreased variability, the time to extubation was shorter with remifentanil than with alfentanil (p = 0.048). There was a similar overall incidence of adverse events in both groups, 82% and 75% of patients, respectively. Adverse events associated with remifentanil were rapidly controlled by dose reductions. The incidence of intra-operative hypotension and bradycardia was higher in the remifentanil group (p < or = 0.033). An initial remifentanil infusion rate of 0.1 microgram.kg-1.min-1 titrated to individual need provided postoperative pain relief in the presence of adequate respiration in 71% of patients. When using remifentanil in the immediate postoperative setting, rapid administration of bolus doses and infusion rate increases resulted in a relatively high incidence of muscle rigidity, respiratory depression and apnoea. Changing the postoperative regimen to avoid rapid changes in remifentanil blood concentration resulted in more effective analgesia and dramatically reduced the incidence of adverse events during this period. In patients undergoing major abdominal surgery, remifentanil appears to offer superior intra-operative haemodynamic stability during stressful surgical events compared with alfentanil without compromising recovery from anaesthesia. Remifentanil can be administered as a postoperative analgesic agent at a starting dose of 0.1 microgram-.kg-1.min-1; however, it should only be used in the presence of adequate supervision and monitoring of the patient. Administration of bolus doses is not recommended in this setting.

Synhimantus (Synhimantus) magnipapillatus n. sp. (Nematoda, Acuarioidea) from the Yellow-crowned Night-heron, Nyctanassa violacea cayennensis (Gmelin) (Aves, Ardeidae).

Synhimantus (Synhimantus) magnipapillatus n. sp., mainly considering the outstanding size of the cervical papillae and the delicate structure of the cephalic cordons, is not related to any other species of the genus, except for S. (S.) laticeps, concerning the similarities regarding the spicules, that justify their comparison.

Cluster headache attacks treated for up to three months with subcutaneous sumatriptan (6 mg). Sumatriptan Cluster Headache Long-term Study Group.

In the first three months of a 24-month open study to assess the safety and efficacy of subcutaneous sumatriptan 6 mg in the long-term acute treatment of cluster headache, 138 patients treated a maximum of two attacks daily each with a single 6 mg injection. A total of 6353 attacks were treated. Adverse events, reported in 28% of sumatriptan-treated attacks, were qualitatively similar to those seen in migraine long-term trials. Their incidence did not increase with frequent use of sumatriptan. There were no clinically significant treatment effects on vital signs, ECG recordings or laboratory parameters. Headache relief (a reduction from very severe, severe or moderate pain to mild or no pain) at 15 min was obtained for a median of 96% of attacks treated. There was no indication of tachyphylaxis, decrease in the speed of response, or increased frequency of attacks with long-term treatment. This study demonstrated that, in long-term use, subcutaneous sumatriptan 6 mg is a well-tolerated and effective acute treatment for cluster headache.

Intranasal sumatriptan for the acute treatment of migraine. International Intranasal Sumatriptan Study Group.

Two double-blind, placebo-controlled, randomised, multicentre, multinational, parallel-group studies were carried out to identify the optimum dose of intranasal sumatriptan for the acute treatment of migraine. Study medication was taken as a single dose through one nostril in the first study, and as a divided dose through two nostrils in the second study. Totals of 245 and 210 patients with a history of migraine were recruited into the one- and two-nostril studies, respectively. In both studies, headache severity had significantly improved at 120 min after doses of 10-40 mg sumatriptan compared to placebo (P < 0.05) and the greatest efficacy rates were obtained with 20 mg sumatriptan. With 20 mg sumatriptan 78% and 74% of patients experienced headache relief in one- and two-nostril studies respectively. Sumatriptan was generally well tolerated, the most frequently reported event being taste disturbance. The results of the two studies are similar and indicate that administering sumatriptan as a divided dose via two nostrils confers no significant advantage over single-nostril administration.