Hyperbaric vs. isobaric bupivacaine for spinal anaesthesia for elective caesarean section: a Cochrane systematic review

Both isobaric and hyperbaric bupivacaine have been used for spinal anaesthesia for elective caesarean section, but it is not clear if one is better than the other. The primary objective of this systematic review was to determine the effectiveness and safety of hyperbaric bupivacaine compared with isobaric bupivacaine administered during spinal anaesthesia for elective caesarean section. We included 10 studies with 614 subjects in the analysis. There was no evidence of differences either in the risk of conversion to general anaesthesia, with a relative risk (95%CI) of 0.33 (0.09–1.17) (very low quality of evidence), or in the need for supplemental analgesia, the relative risk (95%CI) being 0.61 (0.26–1.41) (very low quality of evidence). There was also no evidence of a difference in the use of ephedrine, the amount of ephedrine used, nausea and vomiting, or headache. Hyperbaric bupivacaine took less time to reach a sensory block height of T4, with a mean difference (95%CI) of ?1.06 min (?1.80 to ?0.31). Due to the rarity of some outcomes, dose variability, use of adjuvant drugs and spinal technique used, future clinical trials should look into using adequate sample size to investigate the primary outcome of the need for supplemental analgesia.     

Engineering extracellular matrix structure in 3D multiphase tissues

In native tissues, microscale variations in the extracellular matrix (ECM) structure can drive different cellular behaviors. Although control over ECM structure could prove useful in tissue engineering and in studies of cellular behavior, isotropic 3D matrices poorly replicate variations in local microenvironments. In this paper, we demonstrate a method to engineer local variations in the density and size of collagen fibers throughout 3D tissues. The results showed that, in engineered multiphase tissues, the structures of collagen fibers in both the bulk ECM phases (as measured by mesh size and width of fibers) as well as at tissue interfaces (as measured by density of fibers and thickness of tissue interfaces) could be modulated by varying the collagen concentrations and gelling temperatures. As the method makes use of a previously published technique for tissue bonding, we also confirmed that significant adhesion strength at tissue interfaces was achieved under all conditions tested. Hence, this study demonstrates how collagen fiber structures can be engineered within all regions of a multiphase tissue scaffold by exploiting knowledge of collagen assembly, and presents an approach to engineer local collagen structure that complements methods such as flow alignment and electrospinning.     

Prolonged reactive oxygen species generation and nuclear factor-kappaB activation after a high-fat, high-carbohydrate meal in the obese

BACKGROUND: Because obesity is associated with chronic oxidative and inflammatory stress, and high-fat, high-carbohydrate meals induce significant oxidative and inflammatory stress in normal subjects, we have now hypothesized that the intake of a high-fat, high-carbohydrate meal would result in a greater and more prolonged oxidative and inflammatory stress in the obese than in normal subjects. METHODS: Ten normal-weight and eight obese subjects were given a high-fat, high-carbohydrate meal after an overnight fast. Blood samples were collected at baseline and hourly following the meal for 3 h. RESULTS: Reactive oxygen species generation by mononuclear cells increased significantly by 2 h in both groups but continued to increase significantly at 3 h in the obese subjects, whereas in normal subjects it returned to baseline. Levels of p47(phox) increased significantly (by 81 +/- 26%) at 3 h in obese individuals (P < 0.05), whereas there was no significant change in p47(phox) in normal subjects. Nuclear factor-kappaB DNA binding in mononuclear cells increased significantly (by 48 +/- 58%, P < 0.036) at 2 h but not at 3 h in normal subjects, whereas in the obese, nuclear factor-kappaB increased significantly at both 2 and 3 h (by 36 +/- 57 and 42 +/- 63%, respectively, P < 0.004). Matrix metalloproteinase-9 concentrations were significantly higher in the obese at baseline (580 +/- 103.9 vs. 373 +/- 30.03 ng/ml, P < 0.05) and increased to significantly greater concentrations after the meal than in the lean subjects. CONCLUSIONS: High-fat, high-carbohydrate meals induced a significantly more prolonged and greater oxidative and inflammatory stress in the obese. This may contribute to the increased atherogenic risk in obesity.     

Effects of N-methyl pyrrolidone on the uptake of hypericin in human bladder carcinoma and co-staining with DAPI investigated by confocal microscopy

Photodynamic diagnosis (PDD) using hypericin (HY), a natural photosensitizer, detects bladder cancer significantly better than white light endoscopy. However, the lipophilicity of HY complicates its administration for clinical applications. Currently, pharmaceutical preparations for HY without plasma protein are being developed. Formulations containing a biocompatible solvent, N-methyl pyrrolidone (NMP) have been shown to enhance the photodynamic therapeutic effects of HY. It was recently reported that, NMP formulations of HY were able to produce significantly higher contrast for fluorescence detection of tumors than albumin-containing HY formulations. This present work hypothesizes that NMP acts both as a solvent and penetration enhancer to improve the delivery of HY into cells by increasing the permeability of cell membranes. This paper reports the use of 3-D confocal microscopy to monitor real-time uptake of HY in human carcinoma. 3-D confocal microscopy was used to investigate the possibility of nuclear localization of HY in MGH cells. The fluorescence of HY was confirmed to be emitted from HY containing cells using spectrometry. The localization of a DNA fluorescent probe 4', 6-diamidino-2-phenylindole dihydrochloride (DAPI) was used to confirm the possibility of colocalization of DAPI and HY. The colocalization analysis in the present study suggests that it was very unlikely that HY colocalized in the nucleus that was stained by DAPI. Fluorescein leakage tests showed that 1% NMP changes the permeability of cell membranes, and enhanced the delivery of HY into cells resulting in lower cell survival ratios. Thus, NMP was able to enhance the photodynamic therapeutic effects of HY on cancer cells.     

A review of studies of parent-child communication about sexuality and HIV/AIDS in sub-Saharan Africa

Parent-child sexuality communication has been identified as a protective factor for adolescent sexual and reproductive health, including HIV infection. The available literature on this topic in sub-Saharan Africa is increasing; however a systematic review of studies has not been conducted. This article reviews the literature in the area of parental or caregiver and child communication about sexuality and HIV/AIDS in sub-Saharan Africa. A review of peer reviewed literature published between 1980 and April 2011 was conducted. Communication process studies investigating the frequency, content, style, tone of discussions, preferences, as well as associations with and barriers to sexuality communication are reviewed. In addition, studies which examine behavioral associations with parent-child sexuality communication, and intervention studies to improve parent-child sexuality communication are examined. The findings from process studies suggest wide variation in terms of frequency of discussions, with a range of socio-demographic and other factors associated with sexuality communication. Overall, findings demonstrate that discussions tend to be authoritarian and uni-directional, characterized by vague warnings rather than direct, open discussion. Moreover, parents and young people report a number of barriers to open dialogue, including lack of knowledge and skills, as well as cultural norms and taboos. Findings are less clear when it comes to associations between parental communication and adolescent sexual activity and contraception use. However, nascent indications from intervention research suggest positive findings with increases in frequency and comfort of discussions, among other outcomes. Gaps in the research are identified and discussed with implications for future studies.     

Double vessel acute myocardial infarction showing simultaneous total occlusion of left anterior descending artery and right coronary artery

Simultaneous double vessel acute myocardial infarction (AMI) is extremely rare and usually has poor clinical outcomes. Management of this complicated condition is challenging and time-limited. The case of a 46-year-old Taiwanese man with simultaneous anterior and inferior wall AMI is reported. Rapid deterioration of clinical condition with ventricular fibrillations (VF), cardiogenic shock and asystole developed before catheterization. Coronary angiogram revealed simultaneous total occlusion of left anterior descending (LAD) and right coronary arteries (RCA). Frequent VF attack was still noted after diagnostic catheterization. After cardiopulmonary resuscitation, immediate percutaneous coronary intervention of the LAD and RCA, and intra-aortic balloon counterpulsation was inserted. Due to intractable heart failure and cardiogenic shock, extracorporeal membrane oxygenation was performed. Rabdomyolysis with acute renal failure was also noted with hemodialysis treatment. Thirty-one days after hospitalization, he was discharged with a New York Heart Association functional class III heart failure, without hemodialysis.     

Analgesic efficacy using loss of resistance to air vs. saline in combined spinal epidural technique for labour analgesia

Identification of the epidural space is often performed using the loss of resistance technique to either air or saline. We sought to investigate if the medium used affected the quality of analgesia obtained by parturients who received labour epidurals. We conducted a retrospective audit of labour epidurals performed on nulliparous parturients in our institution from May 2003 to March 2005. All epidural catheters were inserted by senior obstetric anaesthetists using a combined spinal epidural technique. The following information was recorded: parturients' demographic data, loss of resistance technique used, type and amount of local anaesthetic solution administered, complications encountered during procedure, pre-block and post-block pain scores, incidence of breakthrough pain requiring supplemental medication and post-block side-effects. Data from 2848 patients were collected and analysed; 56% of patients made up the saline group and 44% the air group. Patients in both groups had similar demographic profiles and similar incidences of complications and post-block side-effects. However patients in the air group had a higher incidence of recurrent breakthrough pain P = 0.023). We also identified three other factors that were associated with an increased incidence of recurrent breakthrough pain; administration of pre-block oxytocin, sitting position of the parturient during the procedure and the use of intrathecal bupivacaine for induction of analgesia. Our findings suggest that a loss of resistance to air is associated with a higher incidence of recurrent breakthrough pain among parturients who received combined spinal epidural analgesia for labour than a loss of resistance to saline.     

Chlorin e6-polyvinylpyrrolidone as a fluorescent marker for fluorescence diagnosis of human bladder cancer implanted on the chick chorioallantoic membrane model

The use of fluorescence diagnosis as a modern cancer diagnostic modality is rapidly gaining importance in the field of urology. It is based on the detection of distinctive light emission of tissues sensitized by fluorescent dyes, commonly referred to as photosensitizers, after irradiation with a specific light source. Therefore, the search for specific fluorescent dyes with high sensitivity and specificity for bladder cancer is constantly being sought after. The aim of this study is to investigate the use of a new formulation consisting a mixture of chlorin e6 and polyvinylpyrrolidone (Ce6-PVP) for the detection of human bladder cancer cells (MGH) implanted on the chick chorioallantoic membrane (CAM) model. Uptake kinetics studies were quantitatively determined for both systemic and topical administrations of Ce6-PVP to the normal CAM as well as the MGH human bladder tumor implanted on CAM using fluorescence imaging technique. Rapid elimination of Ce6-PVP was displayed following topical application compared to systemic administration in the normal CAM system. Ce6-PVP was found to localize selectively in the xenografted bladder tumor in contrast to the CAM tissue. Neither dark toxicity nor irritancy was observed on the CAM tissue at the dose of 2 mg/kg Ce6-PVP. In conclusion, the Ce6-PVP formulation appeared to have the potential as a fluorescent marker for fluorescence diagnosis of human bladder cancer.     

Porous Ba Ferrite Prepared from Wood Template

Ba ferrite materials with porous microstructures were prepared from a natural cedar wood template in order to investigate new electromagnetic shielding materials. The wood templates were infiltrated with barium nitrate and iron nitrate solutions (molar ratio = 1:12) and dried to form ferrite gel, then, they were sintered in air at a temperature between 800 °C and 1400 °C. The 1-dimensional porous structures were retained after sintering and the pore size was approximately 10–20 μm. These ferrites show large coercive force and anisotropy field. The largest coercive force was obtained for the specimen sintered at 800 °C.