Comparison of two urinary antigen tests for establishment of pneumococcal etiology of adult community-acquired pneumonia

The Binax NOW immunochromatographic test (ICT) detecting the pneumococcal C polysaccharide and a serotype-specific latex agglutination (LA) test detecting 23 pneumococcal capsular antigens were evaluated for establishing pneumococcal etiology in community-acquired pneumonia (CAP) by use of nonconcentrated urine. ICT was considered to be strongly positive for result lines at least as intense as the control line and weakly positive for less intense result lines. When 215 adult CAP patients were tested, strong ICT, weak ICT, and LA positivity were found in 28, 24, and 16 patients, respectively; of these patients, 13 (46%), 6 (25%), and 13 (81%), respectively, had pneumococcal bacteremia and 27 (96%), 17 (71%), and 15 (94%), respectively, had Streptococcus pneumoniae isolated from blood, sputum, and/or nasopharynx. Among 108 controls tested, 2 (1.9%) were weakly ICT positive. When weak positivity was considered negative, the sensitivity of ICT decreased from 79% (19 of 24) to 54% (13 of 24), while the specificity increased from 83% (158 of 191) to 92% (176 of 191); no controls were false positive. The sensitivity and specificity of LA were 54% (13 of 24) and 98% (188 of 191), respectively. Eight of nine LA serotypes corresponded to culture serotypes. In conclusion, using nonconcentrated urine and dividing ICT-positive results into strongly and weakly positive results is a suitable way of performing ICT. While weak ICT positivity should be interpreted with caution, strong ICT positivity and LA positivity should be considered supportive of pneumococcal etiology in adult CAP. As such, these assays might have implications for antibiotic use in CAP. LA has promising potential for pneumococcal serotyping, although further evaluation is required.     

Expression of platelet-derived growth factor-AA is associated with tumor progression in osteosarcoma.

Platelet-derived growth factors are secreted by mesenchymal cells. The homodimer platelet-derived growth factor-AA especially stimulates bone cells through interaction with the platelet-derived growth factor-alpha receptor homodimer. In this study we wanted to determine the expression of the receptor and its ligand in human osteosarcomas and to correlate the expression of platelet-derived growth factor-AA and -alpha receptor with clinicopathological parameters. Fifty-seven osteosarcomas were immunohistochemically analyzed for expression of platelet-derived growth factor-AA and platelet-derived growth factor-alpha receptor. Spearman's correlation coefficient revealed a strong correlation between the expression of platelet-derived growth factor-AA and platelet-derived growth factor-alpha receptor (r = 0.867). No differences were observed relative to gender, age, tumor stage, tumor location, and response to neoadjuvant chemotherapy between high or low platelet-derived growth factor-AA and platelet-derived growth factor-alpha receptor expression. High platelet-derived growth factor-AA expression correlated with tumor progression in univariate analysis (P = .0415; log-rank test), whereas platelet-derived growth factor-alpha receptor expression showed a trend toward a shorter disease-free survival, which failed to reach significance (P = .0627, log-rank test). In multivariate analysis, platelet-derived growth factor-AA expression remained a significant independent predictor of tumor progression (P = .021, Cox regression). Immunohistochemical analysis of platelet-derived growth factor-AA expression in osteosarcoma may be a useful marker of prognosis and may be considered as a possible target for novel therapeutic strategies.     

Relations between chronic stimulation-induced changes in contractile properties and the Ca2+-sequestering system of rat and rabbit fast-twitch muscles

This study compares changes in contractile properties, Parvalbumin content, and Ca²⁺-uptake by the sarcoplasmic reticulum (SR) of low-frequency stimulated rat and rabbit tibialis anterior (TA) muscles. Time to peak tension increased 1.8-fold in 35-day stimulated rabbit TA, while no change occurred in rat TA. Isometric twitch tension increased 2-fold in rabbit TA, but was unaltered in rat TA. Parvalbumin (PA) content was more than 90% reduced in rabbit TA, but only 60% in rat TA after 35 days. At this time, PA content of the stimulated rat TA was still higher than that of normal rabbit TA. Taking into account the suggested role of PA as a cytosolic Ca²⁺ buffer, its decrease could lead to an impaired free Ca²⁺-decay with a prolonged active state and a higher tension output during a single twitch. This would explain why chronic stimulation led to an increase in isometric twitch tension in rabbit TA, but not in rat TA. The 1.6-fold rise in half-relaxation time of 35-day stimulated rat and rabbit TA most likely resulted from a 50% reduced Ca²⁺-uptake by the SR, due to a still unknown modification of the Ca²⁺-transport ATPase.     

Fatty acid synthesis in the arrested rabbit heart during ischemia

In rabbit hearts arrested by a carnosine-buffered cardioplegic solution the incorporation of [1-¹⁴C]acetate into lipids was investigated. After 10–20 and 60 min of ischemia the radioactivities of phospholipids, mono-, di-, and triacylglycerols, acyl-CoA, acylcarnitine, and free fatty acids were determined. In the first period of ischemia mainly acylcarnitine was labelled (ca. 50%) and only 25% of [¹⁴C]-activity was found in phospholipids which showed the lowest specific activity of all lipid classes. After 60 min of ischemia the percentage of total radioactivity of acylcarnitine and phospholipids was decreased, whereas that of neutral lipids was increased to more than 50%. During the increase of total radioactivity the relative specific activity of all lipids decreased except that of triacylglycerols. Only fatty acids up to chain lengths of 16 carbon atoms were labelled. Lauric and myristic acid had high specific activities. These results indicated de novo synthesis of fatty acids accumulating in triacylglycerols during ischemia of the arrested heart.     

Cystatin C predicts renal function impairment after partial or radical tumor nephrectomy

International Urology and Nephrology - To test the value of preoperative and postoperative cystatin C (CysC) as a predictor on kidney function after partial (PN) or radical nephrectomy (RN) in...     

Quality-of-Life Outcome After Laparoscopic Adjustable Gastric Banding for Morbid Obesity

Background: The definition of success and failure of a bariatric procedure should include weight loss as well as improvement of comorbidity and quality-of-life (QoL) assessment. QoL measures changes in physical, functional, mental, and social health in order to evaluate benefits of new programs and interventions. Material and Methods: From April 1995 until March 1999, 287 patients underwent laparoscopic adjustable silicone gastric banding (LASGB) at Northwest Hospital Frankfurt a.M. (Germany). In this study, 100 of 287 patients (preoperative mean BMI 48.3 kg/m²; mean age 35.2 years) with a follow-up >18 month were evaluated. All patients underwent anonymous questionnaire (26 questions with a maximum score of 60) about different aspects of QoL outcome after LSAGB. Results: In this study, 4 of 100 patients refused to give an answer to the QoL questions. Therefore 96 patients were evaluated. The QoL auto-evaluation of the patients shows that QoL generally improved after surgery in 92%. Using the scoring system, 44% of patients have excellent, 52% good, and only 4% bad results. The 4 patients who refused had to be classified as failure. General acceptance of LSAGB is wide, but gastrointestinal side effects are recognizable in more than 78% of operated patients. Successful weight loss is followed by an improvement of comorbidities. Conclusions: Safe, effective bariatric procedures increase the quality of life in morbidly obese patients markedly. Bariatric surgeons are committed to support and help their patients until they reach a new quality of life after obesity surgery.     

In vitro evaluation of the viscoelastic properties of chitosan-thioglycolic acid conjugates.

The aim of this study was to evaluate the viscoelastic properties of chitosan-thioglycolic acid conjugates with different amounts of thiol groups immobilized on the polymer. The modification of chitosan was achieved via the covalent attachment of thioglycolic acid mediated by a carbodiimide. Chitosan-thioglycolic acid conjugates displaying 120, 209 and 439 microM thiol groups per gram of polymer were synthesized. The rheological properties of the three different conjugates were investigated. The elastic properties of the gels were found to increase significantly at pH 5.5. After 6 h the elastic modulus G' of chitosan-TGA 120, chitosan-TGA 209 and chitosan-TGA 439 gels increased 7-, 32- and 168-fold, respectively. In parallel the formation of disulfide bonds was observed. Accordingly, proof of principle that chitosan modified by the introduction of thiol groups has in situ gelling properties due to the formation of inter- and intramolecular disulfide bonds at physiological pH values is provided. Based on their in situ gelling properties, chitosan-thioglycolic acid conjugates seem to be very promising new excipients for liquid or semisolid formulations which should stabilize themselves once applied on the site of drug delivery.     

Effect of Pluronic L-81 on intestinal lipoprotein secretion in the rat

The hydrophobic nonionic detergent Pluronic L-81 has been shown to lower plasma very-low-and low-density lipoprotein cholesterol, thus preventing diet-induced atherogenesis. The major effect of this agent is a pronounced interference with intestinal lipid metabolism. For studying mesenteric lymph lipoproteins during detergent exposure, a combined micromorphological and biochemical assessment of mucosa and lymph during steady-state lipid absorption was performed. Pluronic L-81 was infused intraduodenally at a constant rate in combination with mixed micellar solutions or saline in mesenteric lymph fistula rats. Pluronic L-81 impairs transepithelial lipid flux during fat absorption, trapping export lipids within the enterocytes and leading to a cytosolic and endoplasmic reticulum lipid accumulation sparing the Golgi region. Pluronic L-81 markedly (P<0.001) reduces mesenteric triglyceride, phospholipid, and total cholesterol secretion almost exclusively by a reduction of chylomicron formation. Chylomicron and very-low-density lipoprotein lipid composition was only insignificantly altered, except for somewhat higher phospholipid/triglyceride ratios. The chylomicron apoprotein pattern was almost unaffected. Thus, chylomicron formation decreased dramatically without major compositional alterations. The reduction of lipid and apoprotein secretion without particle augmentation is not in favour of a selective interference of Pluronic L-81 with intestinal apoprotein B-48 secretion.Parts of this work have been presented at the Annual Meeting of the American Gastroenterological Association, Washington, DC, May 1989, and published in abstract form (1).