Partial congenital defect of the left pericardium: angiographic diagnosis and treatment by thoracoscopic pericardiectomy: case report

Twenty-six patients with an intracardiac myxoma underwent surgical resection at our institution from 1977 through 1992. Left atrial myxoma was diagnosed in 22 patients, left ventricular in 1, right atrial in 2, and right ventricular in 1. Six patients were asymptomatic; preoperative symptoms included dyspnea, arrhythmias, embolic episodes, and syncope. The diagnosis was established with transthoracic echocardiography in all cases but one. Surgery was performed in all cases with the aid of cardiopulmonary bypass with moderate hypothermia and cold crystalloid cardioplegia. One patient with a left ventricular myxoma died in a comatose state during the immediate postoperative period. Long-term clinical and echocardiographic evaluation was performed in 19 patients; results were excellent (all the patients were in New York Heart Association functional class I or II), and no recurrences were documented. The clinical characteristics, diagnostic methods, and surgical approach are presented and discussed.     

High char‐yielding poly[acrylonitrile‐co‐(itaconic acid)‐co‐(methyl acrylate)]: synthesis and properties

Polyacrylonitrile terpolymers of various compositions consisting of acrylonitrile (AN), itaconic acid (IA) and methyl acrylate (MA) were synthesized by solution polymerization in dimethylsulfoxide. Increase in concentration of either IA or MA retarded the overall polymerization rate and the polymer molecular weight. The system consisting of AN + MA and varying IA concentration was more prone to retardation in comparison with the system composed of AN + IA with variable MA concentration. The retardation factors were quantified. Minor quantities of MA boost the reactivity of IA in the terpolymer system. The terpolymer was richer in MA vis‐à‐vis the feed. The thermal characteristics of the terpolymer were examined as a function of its composition. In contrast to the copolymer of AN and IA requiring 1–1.5 mol% IA, the terpolymer required an IA content of approximately 2.5 mol% for optimum thermal stability. The polymer with 90 mol% AN, 2.5 mol% IA and 7.5 mol% MA exhibited reasonably good char‐forming characteristics and thermal stability. The overall crystallinity and crystallite size of the polymers were found to decrease on incorporation of the comonomers. The ‘aromatization index’ of the copolymer increased with the temperature of pyrolysis through re‐organization of the tetrahydropyridine ladder structure. Copyright © 2005 Society of Chemical Industry     

High yield formation of carbon nanotubes using a rotating cathode in open air

Carbon nanotubes (CNTs) have been synthesized using the arc discharge method with a rotating graphite disc as the cathode. Arcing was carried out in open air and without the use of catalysts. The current density was maintained constant through out the experiment, while, the rate of rotation of the cathode and atmosphere under which arcing was carried out were changed during experimentation. Characterization of the samples produced indicates that rotation of the cathode has a significant impact on the quality and yield of the process. It is proposed that rotation of the cathode drags plasma formed between two electrodes away from high temperature region. This results in a sudden quenching of the reactive plasma. The time available for nucleation and growth phenomena is significantly reduced and thus leads to the formation of highly graphitic multi walled CNTs (yield 60%) and traces of double walled CNTs.     

Novel NMDA antagonists: replacement of the pyridinium ring of 6,11-ethanobenzo[b]quinolizinium cations with heteroisoquinolinium cations

Replacement of the pyridinium ring of 6,11-ethanobenzo[b]quinolizinium cations with thiazolium (4a and 4b) and N-methylimidazolium (4c and 4d) resulted in equipotent compounds in the [3H]TCP binding assay. The corresponding N-methyl-1,2,4-triazolium analogs were less potent in this assay. The thiazolium derivative 4b, with a Ki = 2.9 nM, is being evaluated as a possible neuroprotective N-methyl-D-aspartic acid (NMDA) antagonist.     

Chemokine receptors: structure, function and role in microbial pathogenesis

The chemokine superfamily is composed of at least 20 different leukocyte chemoattractants that act by binding to a family of G protein-coupled receptors. Leukocyte subtypes respond preferentially to unique but overlapping subsets of chemokines as determined by the receptor distribution, yet the receptors appear to signal through a common Gi-type G protein. Since chemokines appear to play major roles in inflammatory pathology, their receptors may be good targets for developing leukocyte selective anti-inflammatory drugs. Two chemokine receptors, CC CKRS and ONCC, function pathologically as cell entry factors respectively for human immunodeficiency virus 1, the cause of AIDS, and Plasmodium vivax, the major cause of malaria.     

Computerized determination of proliferating cell nuclear antigen expression in meningiomas. A comparison with non-automated method

Proliferating cell nuclear antigen (PCNA) expression has been proven to be a significant marker of cell proliferation in meningiomas, which correlates with growth rate and, as shown by several authors, possibly provides prognostic information concerning biologic behavior. However, the current method for determining PCNA labeling index (LI) is tedious and time consuming like all the nonautomated methods for evaluating cell kinetics, presenting high interobserver and interlaboratory variability and low reproducibility. In the present study, we introduce a semi-automated computer-assisted image analysis method for determining PCNA LI in 38 meningiomas, in parallel with the current nonautomated method. Image analysis technique permits unbiased cell counting, standardizes the degree of staining intensity and provides instant results. By calculating coefficient of variability, the method proved to be highly reproducible. The correlation between the results provided by the nonautomated and the semiautomated image analysis method showed a high agreement between them, with a correlation coefficient, r, of 0.82. In conclusion, we consider that image analysis contributes to the accuracy, reproducibility, and practicality of PCNA LI determination so that along with other useful parameters this significant marker may serve to predict the clinical behavior in meningiomas.     

Mal de Meleda: a report of four cases from the United Arab Emirates

Scanning electron microscopy was used to study the effect of cyclophosphamide (Cy) on molar development in 18 Sprague-Dawley rats from 15 to 48 days of age after birth. Doses of 30 mg/kg body weight of Cy dissolved in 1 ml 0.9% NaCl were given to the rats at 10 and 13 days of age. Eighteen control rats had injections of 1 ml 0.9% NaCl at the same ages. The most obvious changes in the experimental teeth were found in the developing roots of the first and second molars and in both the crown and roots of the third molar. The roots of the first and second molars were short and showed apical closure in the experimental rats. In addition to the disturbances in crown and root formation, the third molars were also significantly reduced in total size as compared with the third molars in the control rats.     

Antiserum against Escherichia coli J5 contains antibodies reactive with outer membrane proteins of heterologous gram-negative bacteria

The binding of IgG in antiserum to Escherichia coli J5 to the surface of Enterobacteriaceae and to cell wall fragments released from serum-exposed bacteria was studied in a search for potentially protective epitopes other than lipopolysaccharide (LPS). IgG titers to multiple heterologous gram-negative smooth bacteria increased following incubation of the bacteria in serum and decreased following absorption with serum-exposed heterologous bacteria. IgG eluted from absorbing bacteria bound to at least three conserved bacterial outer membrane proteins (OMPs), but not LPS, as assessed by immunoblotting. The same OMPs were present in LPS-containing macromolecular cell wall fragments released by incubation of heterologous gram-negative bacteria in human serum. Part of the protection offered by J5 antiserum could be from binding of IgG to conserved OMPs at the bacterial surface or to OMPs in cell-wall fragments released from dying bacteria.