Effect of intravenous lidocaine infusion on sevoflurane requirements as monitored by bispectral index: A randomized double-blinded controlled study

AbstractIntroductionSystemic administration of lidocaine significantly decreased propofol requirements when compared to patients receiving placebo. Several studies conducted on animals have proved that systemic local anesthetics reduced minimum alveolar concentration (MAC) of inhalational anesthetics. The aim of this investigation is to study the effect of intravenous administration of lidocaine on the minimum alveolar concentration of sevoflurane required to keep BIS between 40 and 60 during maintenance of anesthesia in humans.MethodsTwenty-eight ASA I–II adults planned to undergo laparoscopic procedures expected to last <2h under general anesthesia were randomly assigned to 2 groups. After standardized induction of general anesthesia, patients were given IV lidocaine bolus (1.5mgkg−1) followed by 2mgkg−1h−1 infusion (group L, n=14) or equal volumes of saline (group C, n=14). Primary outcome of the study was end-tidal sevoflurane at bispectral index (BIS) values of 40–60. Secondary outcomes included doses of opioids, BIS values, and extubation time.ResultsThe median doses of intraoperative fentanyl (range) in group C were similar to group L (P=0.08). There were no significant differences between the 2 groups regarding BIS at any time point. End-tidal sevoflurane concentrations were significantly higher in group C than in group L at all intraoperative time points (P<0.05). Extubation time was longer in group L than in group C (P=0.04).ConclusionIn conclusion, intravenous lidocaine administration, during maintenance of general anesthesia, can decrease BIS-guided sevoflurane requirements

A comparative study between magnesium sulphate and dexmedetomidine for deliberate hypotension during middle ear surgery

AbstractBackgroundThis study was designed to compare magnesium sulphate with dexmedetomidine, regarding their efficiency in inducing deliberate hypotension and providing a better surgical field exposure during middle ear surgery. It also compared the influence of their use on postoperative pain and recovery time.MethodsEighty-eight adult patients undergoing middle ear surgery were included. Patients were randomly divided into two equal groups. Patients were assigned to receive either magnesium sulphate (M group) or dexmedetomidine (D group). Anaesthesia was induced by propofol 2mg/kg iv and fentanyl 1μg/kg. Patients in the M group received an iv bolus of magnesium sulphate 50mg/kg in a total of 100ml saline over 10min followed by infusion of 15mg/kg/h until the end of surgery. Similarly, patients in the D group received dexmedetomidine 1μg/kg over 10min followed by 0.4–0.8μg/kg/h until the end of operation. The target MAP during operation was between 60 and 70mmHg. The surgeon who was blinded of the selected hypotensive agent was asked to assess the quality of the surgical field. In the postanaesthesia care unit (PACU), postoperative pain was assessed and recovery time was recorded.ResultsBoth study drugs succeeded to reach the target MAP. The quality of the surgical field was not different between the two groups. Postoperative pain was not different between the two group and only eight patients in the M group and seven patients in the D group required analgesics. Recovery time was significantly longer for the patients in group D (p<0.05).ConclusionWe concluded that both magnesium sulphate and dexmedetomidine successfully induced deliberate hypotension in patients undergoing middle ear surgery but magnesium sulphate was associated with shorter recovery time and earlier discharge from the PACU

Effect of relining, cement type, and thermocycling on push-out bond strength of fiber reinforced posts.

Statement of the problem: Improving the adaptation of fiber reinforced posts through relining may affect the retention of the posts. Purpose: To investigate the effect of post relining, cement type, and thermocycling on the push-out bond strength of fiber reinforced posts. Materials and methods: (48) endodontically treated human teeth were excessively flared using diamond stones. The teeth were divided into two groups; group (1) (n ¼ 24) received glassix glass fiber posts adapted to the flared canals by relining with composite resin and group (2) (n ¼ 24) received non-relined glassix glass fiber post. Samples of each group were divided into three subgroups (n ¼ 8) according to the type of cement used; subgroup (a): luted using Metacem Refill, a total etch resin cement, subgroup (b): luted using Rely X Unicem, a self-adhesive resin cement and subgroup (c): luted using RelyX Luting, a resin modified glass ionomer cement. Half the samples of each subgroup (n ¼ 4) were subjected to thermocycling. The samples were sectioned horizontally into 2 mm thick slices yielding 3 sections for each sample. Retention was evaluated using push out bond strength test using universal testing machine. The maximum failure load was recorded and used to calculate the push-out bond strength. Data was statistically analyzed and mode of failure was assessed using magnifying glass. Results: Relined posts showed statistically significantly higher mean push-out bond strength than non-relined posts. Rely X Unicem showed the statistically significantly highest mean push-out bond strength among tested cements. Metacem showed significantly lower mean push-out bond strength than Rely X Unicem. Rely X Luting showed the statistically significantly lowest mean push-out bond strengths. There was no statistically significant difference between mean push-out bond strength with and without thermocycling. Most failures occurred at the cementedentin interface in the relined group, while adhesive failure occurred at the cement-post interface in non-relined group

Effect of different surface treatments on bond strength, surface and microscopic structure of zirconia ceramic

Objectives: To evaluate the effect of different surface treatments; plasma treatment, silica coating using plasma technology and sandblasting, on bond strength, surface roughness and microscopic structure of yttria-stabilized tetragonal zirconia polycrystals(Y-TZP) after thermo-cycling. Matrials and methods: One hundred discs (n ¼ 100) of yttria-stabilized tetragonal zirconia were prepared from (Y-TZP) ceramic blocks using MAD/MAM milling technology, and were divided into four equal groups (n ¼ 25) according to the type of surface treatment. Group (1): control (no surface treatment). Group (2): zirconia discs were sandblasted by alumina particles. Group (3): zirconia discs treated by plasma technology to produce surface roughness. Group (4): zirconia discs coated by silica using plasma technology. Samples of each group were subdivided into four subgroups according to different analytical techniques. Subgroup (A): (n ¼ 10) subjected to testing of bond strength of zirconia discs to adhesive resin cement after thermo-cycling. Subgroup (B): (n ¼ 5), to evaluate the microscopic changes of zirconia discs by scanning electron microscope (SEM). Subgroup(C): (n ¼ 5) to evaluate the crystal structure and phase transformation of YZ ceramic by X-ray diffraction (XRD). Subgroup (D): (n ¼ 5) to measure three dimensional surface roughness of YZ ceramic by optical interference microscope. Results: Statistical analysis of shear bond strength by ANOVA revealed the presence of no statistically significant difference between group (3) and (4); both showed the statistically significantly highest mean shear bond strength values. Group (2) showed statistically significantly lower mean values followed by group (1). SEM showed that the topographic pattern differed by different surface treatments of samples. XRD revealed that; group (1) showed the statistically significantly highest mean % of zirconium oxide (Tetragonal phase). Group (2) showed the statistically significantly lowest mean % of Zirconium oxide (Tetragonal phase) and highest mean % of Boehmite and Zirconium oxide (Anorthic phase); Group (3) and (4) showed the statistically significantly highest mean % of Zirconium oxide (Monoclinic phase) and low % of zirconium oxide (Tetragonal phase). 3D- optical surface roughness showed that group (3) and (4) had highest mean (Ra) values. Group (2) showed statistically significantly lower mean values. Group (1) showed the statistically significantly lowest mean (Ra) values. Conclusions: (1) Surface treatments of Y-TZP ceramic together with MDP primer and silane-coupling agent application improve the bond strength to resin cement. (2) Plasma-Silica coating and plasmaoxygen treatment, both are valuable methods that improve the bond strength of resin cement to YTZP ceramic. (3) Silica coating by plasma technology provides durable bond strength and can be a promising alternative pretreatment before silane application to enhance bonding with zirconia ceramic. (4) Tetragonal-monoclinic phase transformation had occurred in Y-TZP samples received both types of plasma treatment

Calcium Carbonate Suppresses Haem Toxicity Markers without Calcium Phosphate Side Effect on Colon Carcinogenesis

Red meat intake is associated with increased risk of colorectal cancer. We have previously shown that haemin, haemoglobin and red meat promote carcinogen-induced preneoplastic lesions, aberrant crypt foci, in the colon of rats. We have also shown that dietary calcium phosphate inhibits haemin-induced promotion, and normalizes faecal lipoperoxides and cytotoxicity. Unexpectedly, high-calcium phosphate control diet-fed rats had more preneoplastic lesions in the colon than low-calcium control diet-fed rats. The present study was designed to find a calcium supplementation with no adverse effect, by testing several doses and types of calcium salts. One in vitro study and two short-term studies in rats identified calcium carbonate as the most effective calcium salt to bind haem in vitro and to decrease faecal biomarkers previously associated with increased carcinogenesis: faecal water cytotoxicity, thiobarbituric acid reactive substances. A long term carcinogenesis study in dimethylhydrazine-injected rats demonstrated that a diet containing 100 µmol/g calcium carbonate did not promote aberrant crypt foci, in contrast with previously tested calcium phosphate diet. The results suggest that calcium carbonate, and not calcium phosphate, should be used to reduce haem-associated colorectal cancer risk in meat-eaters. They support the concept that the nature of the associated anion to a protective metal ion is important for chemoprevention

Freeze-Dried Ham Promotes Azoxymethane-Induced Mucin-Depleted Foci and Aberrant Crypt Foci in Rat Colon

Processed and red meat consumption is associated with the risk of colorectal cancer. Meta-analyses have suggested that the risk associated with processed meat is higher. Most processed meats are cured and cooked, which leads to formation of free nitrosyl heme. We speculated that free nitrosyl heme is more toxic than native myoglobin. The promoting effect of a freeze-dried, cooked, cured ham diet was looked for in a 100-day study. Colon carcinogenesis endpoints were aberrant crypt foci and mucin depleted foci (MDF). A second study (14 days) was designed 1) to compare the effect of ham, hemoglobin, and hemin; and 2) to test the effect of sodium chloride, nitrite, and phosphate in diet on early biomarkers associated with heme-induced promotion. In the 100-day study, control and ham-fed rats had 3.5 and 8.5 MDF/colon, respectively (P < 0.0001). Promotion was associated with cytotoxicity and lipid peroxidation. In the short-term study, cytotoxicity and lipid peroxidation of fecal water, and the urinary marker of lipid peroxidation, increased dramatically in ham- and hemin-fed rat. In contrast, the hemoglobin diet, sodium chloride, nitrite, phosphate diet had no effect. Freeze-dried cooked ham can promote colon carcinogenesis in a rodent model. Hemin, but not hemoglobin, mimicked ham effect on early biochemical markers associated with carcinogenesis

Potential antidiabetic effect of ethanolic and aqueous-ethanolic extracts of Ricinus communis leaves on streptozotocin-induced diabetes in rats

Recently, herbal drugs and their bioactive compounds have gained popularity in the management of diabetes mellitus (DM), which has become an epidemic disease all over the world and is especially prevalent in the Kingdom of Saudi Arabia (KSA). This study aimed to investigate the antidiabetic effect of ethanolic and aqueous-ethanolic extracts of wild Ricinus communis (R. communis) leaves in streptozotocin (STZ) induced diabetic rats. Diabetic rats were administered orally with the mentioned extracts at doses of 300 and 600 mg/kg/BW for 14 days, and the obtained results of different biochemical parameters were compared with normal control, diabetic control and standard drug glibenclamide (5 mg/kg/BW). The obtained results revealed a remarkable and significantly (P < 0.05) reverse effect of the body weight loss, observed when diabetic rats were treated with ethanol and aqueous-ethanol extracts at 300 mg/kg/BW. Administration of the ethanol extract at 600 mg/kg/BW significantly (P < 0.05) reduced the blood glucose level. A significant increase in the AST, ALT and ALP levels (P < 0.05) was observed in the diabetic control and in the experimental groups with glibenclamide which was also significantly (P < 0.05) lowered after treatment with extracts at special doses. Total proteins, albumin, total bilirubin, direct bilirubin, creatinine and urea were also investigated and compared to the corresponding controls. We showed that administration of R. communis extract generally significantly (P < 0.05) ameliorated the biochemical parameters of diabetic rats. Also, the changes in serum electrolyte profile were assessed and the results demonstrate that administration of extracts at concentration of 600 mg/kg/BW generally inhibits the alteration maintain their levels. The obtained data imply the hypoglycemic effects of this plant, which may be used as a good alternative for managing DM and therefore validating its traditional usage in KSA

Potential Role of Platelet-Derived Growth Factor Receptor Inhibition Using Imatinib in Combination with Docetaxel in the Treatment of Recurrent Non-small Cell Lung Cancer

Introduction:Platelet-derived growth factor receptor (PDGFR) is expressed in lung cancer and is involved in angiogenesis. Preclinical models demonstrated that imatinib (Im) regulates angiogenesis through PDGFR inhibition and enhances efficacy of chemotherapy. Hypothesis: We hypothesized that Im plus docetaxel (D) would have a synergistic effect detectable by an increase in response rate in patients with recurrent non-small cell lung cancer (NSCLC).Methods:A phase II trial to evaluate Im in combination with D in patients with recurrent NSCLC was conducted. The primary end point was response rate, using a Simon two-stage design. Eligible patients had measurable disease and no more than two chemotherapy regimens. D was given at 30 mg/m2/wk intravenously ×3 every 4 weeks and oral Im at 600 mg daily for four cycles. Patients required two cycles to be evaluable for response. Nonprogressors after four cycles continued with Im maintenance until progression or for a total of 12 months.Results:Twenty-three patients were enrolled in the first stage. Toxicity was mainly nonhematologic. We observed one partial response (5.5%), four stable disease (22.2%), and 13 progressed (72.2%). Median time to progression was 1.9 months, and median overall survival was 6.1 months. Two patients who went on Im maintenance had time to progression of 7.78 months and 15.8 months.Conclusion:Im in combination with D did not achieve its primary objective of improving response rate in patients with recurrent NSCLC. An increased understanding of the complex PDGFR pathway in lung cancer and alternative strategies to inhibit it are needed