Total chlorine in coal seam profiles from the South Staffordshire (Cannock) coalfield

In a coalfield of noted high-chlorine coals, seam profiles were taken from two collieries. Three seam profiles from each colliery were analysed for total chlorine to try to correlate chlorine level with position in the seam. Moisture contents and ash yields were determined for four of the seams. Total chlorine is highest in the coals, reaching 1 wt%, and low in the mudrocks, down to 0.08 wt%. Intermediate chlorine values are associated with dirty coals and carbonaceous mudrocks. Water centrifuged from an intraseam dirt band showed that the moisture held the total chlorine content. Similar element ratios were achieved from water centrifuged from coal. These results, together with National Coal Board groundwater data, suggest that the majority of chlorine in coal has been introduced by chloride-rich groundwaters which evolved during diagenesis, as has been suggested for Illinois and Nottinghamshire coals. There is a very significant positive correlation between coal moisture and total chlorine contents. Total chlorine levels are thus thought to be controlled by groundwater concentration levels and coal porosity, hence the positive relationship between organic carbon and chlorine concentrations. Total chlorine levels vary through the seams, but there is not a consistent change with position in the seam. There exists a correlation between coal type and total chlorine content. Bright coals hold significantly more chlorine than dull coals, owing to different porosities of the coal macerals. Departures from this relationship with coal type may be explained by mineral matter dilution or the ingress of recent groundwaters, overriding the original coal type-chlorine relationship.     

Clinical predictors of implantable cardioverter-defibrillator shocks (results of the CASCADE trial). Cardiac Arrest in Seattle, Conventional versus Amiodarone Drug Evaluation

The Cardiac Arrest in Seattle, Conventional Versus Amiodarone Drug Evaluation (CASCADE) study evaluated antiarrhythmic drug therapy in high-risk survivors of out-of-hospital ventricular fibrillation. Antiarrhythmic drug therapy for 228 patients was randomized to amiodarone or conventional antiarrhythmic drugs. Additional therapy with an implantable cardioverter-defibrillator was provided to 105 of these patients. Clinical predictors of shocks were evaluated for the 88 patients with coronary artery disease (amiodarone 46, conventional 42), treated with an implantable cardioverter-defibrillator. Survival free of all shocks at 2 years was 77% for patients taking amiodarone and 42% for those receiving conventional therapy (p = 0.014). Two-year survival free of syncopal shocks was 98% for amiodarone-treated patients and 81% for those receiving conventional agents (p = 0.01). Multiple clinical factors were evaluated by Cox analysis for potential clinical predictors of shocks. The independent clinical predictors of shocks were low ejection fraction (p = 0.002), female gender (p = 0.007) and conventional antiarrhythmic drug therapy (p = 0.015). The only independent predictor of a shock associated with syncope was conventional antiarrhythmic drug therapy (p = 0.035). Patients treated with amiodarone receive fewer shocks than patients treated with conventional drug therapy.     

Reduction pneumoplasty for giant bullous emphysema. Implications for surgical treatment of nonbullous emphysema

A review of the literature on reduction pneumoplasty for giant bullous emphysema was undertaken to identify current criteria for this surgical treatment and in the hope of obtaining insights into evaluating reduction pneumoplasty for nonbullous emphysema. Twenty-two retrospective case series, published since 1950, were retrieved by a computer search of the literature and a search of the Index Medicus prior to 1966. Reduction pneumoplasty is most effective when bullae are larger than one third of a hemithorax with evidence of compression of adjacent lung tissue and an FEV1 of less than 50% predicted; the presence of emphysema in nonbullous lung and the amount of compression are best judged by CT. The rationale for reduction pneumoplasty for nonbullous emphysema is supported by the similar early functional changes after reduction pneumoplasty for bullous and nonbullous-improvement of blood gas values and lung mechanics. A single study showing that decline of lung function after surgery for bullous emphysema was less in those who stopped smoking than in those who continued to smoke supports the need for preoperative and maintained smoking cessation in patients receiving reduction pneumoplasty. After 4 decades, the duration of improvement in lung function, whether worsening of emphysema occurs in remaining lung, and late morbidity and mortality after reduction pneumoplasty for bullous emphysema are not well defined. A registry with an unoperated-on comparison group could more rapidly accumulate such data after reduction pneumoplasty for nonbullous emphysema.     

Outcome of post-transfusion hepatitis C: disease severity in blood-component recipients and their implicated donors

BACKGROUND: Oral teratomas are rare entities. CASE: A patient was referred for elevations in the maternal serum alpha-fetoprotein. On ultrasound examination, a cyst was seen protruding from the fetal mouth. Postnatally, a teratoma was found to be filling the neonate's oral cavity. CONCLUSION: This case illustrates problems in determining the etiology of head and neck masses antenatally. It also shows that teratomas can appear to regress and yield positive amniotic fluid alpha-fetoprotein and acetyl-cholinesterase. The appropriate perinatal management of this potentially devastating disorder includes preparation for establishing an airway following delivery.     

Effect of helical CT on the frequency of sedation in pediatric patients

OBJECTIVE: We compared the use of sedation for helical CT examination of pediatric patients with that for conventional CT studies. MATERIALS AND METHODS: We retrospectively compared two 4-month periods of CT examinations that differed only in that conventional CT was routinely used in one period and helical CT was exclusively used in the other period. For these two periods, we compared the type and number of CT examinations, the sedation used (if any), and the age of patients who required sedation. RESULTS: We performed 1055 conventional CT examinations in 762 pediatric cancer patients. Of the 264 children who were 8 years old or younger, 107 had been sedated. In comparison, 1195 helical CT examinations were performed on 838 patients: of the 246 children 8 years old or younger, 51 received sedation. For both study groups, the mean and median age of the patients was 4 years old. The mean age of patients requiring sedation was 21 (conventional CT) or 20 months (helical CT); the median age of patients who required sedation was 2 years old for both study groups. Patients who were 8 years old or younger and who underwent helical CT required sedation 49% less frequently than such patients who underwent conventional CT. The most dramatic reduction occurred among patients who were 3 years old or younger (p < or = .004). CONCLUSION: Use of helical CT reduced the need for sedation among our pediatric patients. Fewer sedations may reduce the risk of complications, decrease disruption of the patient's normal daily activities, and improve patient throughout. The associated savings in personnel time and pharmaceutical costs can be redistributed.     

Consequences of neonatal seizures in the rat: morphological and behavioral effects

Whereas neonatal seizures are a predictor of adverse neurological outcome, there is controversy regarding whether seizures simply reflect an underlying brain injury or can cause damage. We subjected neonatal rats to a series of 25 brief flurothyl-induced seizures. Once mature the rats were compared with control littermates for spatial learning and activity level. Short-term effects of recurrent seizures on hippocampal excitation were assessed by using the intact hippocampus formation preparation and long-term effects by assessing seizure threshold. Brains were analyzed for neuronal loss, sprouting of granule cell axons (mossy fibers), and neurogenesis. Compared with controls, rats subjected to neonatal seizures had impaired learning and decreased activity levels. There were no differences in paired-pulse excitation or inhibition or duration of afterdischarges in the intact hippocampal preparation. However, when studied as adults, rats with recurrent flurothyl seizures had a significantly lower seizure threshold to pentylenetetrazol than controls. Rats with recurrent seizures had greater numbers of dentate granule cells and more newly formed granule cells than the controls. Rats with recurrent seizures also had sprouting of mossy fibers in CA3 and the supragranular region. Recurrent brief seizures during the neonatal period have long-term detrimental effects on behavior, seizure susceptibility, and brain development.     

Enhancement of MR images using registration for signal averaging

Recent studies indicate that arsenic may generate reactive oxygen species to exert its toxicity. However, the mechanism is still unclear. In this study, we demonstrate that arsenite is able to induce apoptosis in a concentration- and time-dependent manner; however, arsenate is unable to do so. An increase of intracellular peroxide levels was accompanied with arsenite-induced apoptosis, as demonstrated by flow cytometry using DCFH-DA. N-Acetyl-L-cysteine (a thiol-containing antioxidant), diphenylene iodonium (an inhibitor of NADPH oxidase), 4,5-dihydro-1,3-benzene disulfonic acid (a selective scavenger of O2-), and catalase significantly inhibit arsenite-induced apoptosis and intracellular fluorescence intensity. In contrast, allopurinol (an inhibitor of xanthine oxidase), indomethacin (an inhibitor of cyclooxygenase), superoxide dismutase, or PDTC had no effect on arsenite-induced cell death. Activation of CPP32 activity, PARP (a DNA repair enzyme) degradation, and release of cytochrome c from mitochondria to the cytosol are involved in arsenite-induced apoptosis, and Bcl-2 antagonize arsenite-induced apoptosis by a mechanism that interferes in the activity of CPP32. These results lead to a working hypothesis that arsenite-induced apoptosis is triggered by the generation of hydrogen peroxide through activation of flavoprotein-dependent superoxide-producing enzymes (such as NADPH oxidase), and hydrogen peroxide might play a role as a mediator to induce apoptosis through release of cytochrome c to cytosol, activation of CPP32 protease, and PARP degradation.     

TESTS FOR SELECTION OF MALTING QUALITY USING UNMODIFIED BARLEY

Various tests for malting potential based on unmodified barley were evaluated. These were based on NearInfraRed Reflectance Spectrophotometry (NIR), sedimentation of meals in cold alcohol or Lactic Acid/Sodium dodecyl sulphate solution, the content of total β glucan as measured by the viscosity of acidic extracts. NIR and sedimentation in Lactic Acid/SDS were found to be the most applicable to the breeding programme at this Institute, whereas the methods based on total β glucan or sedimentation in cold alcohol were unsuitable. The method based on soluble β glucan was only suitable to a breeding programme in which parents with known high β glucan content were used. An hypothesis for the contribution of total β glucan to malting quality is presented. None of the tests investigated were affected by declining dormancy or water sensitivity in the grain.     

Characterization of the lipid-carrier involved in the synthesis of enterobacterial common antigen (ECA) and identification of a novel phosphoglyceride in a mutant of Salmonella typhimurium defective in ECA synthesis

The polysaccharide chains of enterobacterial common antigen (ECA) consist of linear trisaccharide repeat units with the structure -->3)-alpha-d-Fuc4NAc-(1-->4)-beta-d-ManNAcA-(1--> 4)-alpha-d-GlcNAc-(1-->, where Fuc4NAc is 4-acetamido-4, 6-dideoxy-d-galactose, ManNAcA is N -acetyl-d- mannosaminuronic acid, and GlcNAc is N -acetyl-d-glucosamine. The major form of ECA (ECAPG) consists of polysaccharide chains that are believed to be covalently linked to diacylglycerol through phosphodiester linkage; the phospholipid moiety functions to anchor molecules in the outer membrane. The ECA trisaccharide repeat unit is assembled as a polyisoprenyl-linked intermediate which has been tentatively identified as Fuc4NAc-ManNAcA-GlcNAc-pyrophosphorylundecaprenol (lipid III). Subsequent chain-elongation presumably occurs by a block-polymerization mechanism. However, the identity of the polyisoprenoid carrier-lipid has not been established. Accordingly, the current studies were conducted in an effort to structurally characterize the polyisoprenyl lipid-carrier involved in ECA synthesis. Isolation and characterization of the lipid carrier was facilitated by the accumulation of a ManNAcA-GlcNAc-pyrophosphorylpolyisoprenyl lipid (lipid II) in mutants of Salmonella typhimurium defective in the synthesis of TDP-Fuc4NAc, the donor of Fuc4NAc residues for ECA synthesis. Analyses of lipid II preparations by fast atom bombardment tandem mass spectroscopy (FAB-MS/MS) resulted in the identification of the lipid-carrier as the 55-carbon polyisoprenyl alcohol, undecaprenol. These analyses also resulted in the identification of a novel glycolipid which copurified with lipid II. FAB-MS/MS analyses of this glycolipid revealed its structure to be 1,2-diacyl- sn -glycero-3-pryophosphoryl-GlcNAc-ManNAcA (DGP-disaccharide). An examination of purified ECAPGby phosphorus-31 nuclear magnetic resonance spectroscopy confirmed that the polysaccharide chains are linked to diacylglycerol through phosphodiester linkage. Thus, DGP-disaccharide does not appear to be an intermediate in ECAPGsynthesis. Nevertheless, although the available evidence clearly indicate that lipid II is a precursor of DGP-disaccharide, the function of this novel glycolipid is not yet known, and it may be an intermediate in the biosynthesis of a molecule other than ECAPG.