The Glycosylation Mechanisms of 6,3-Uronic Acid Lactones.

Uronic acids are important constituents of polysaccharides found on the cell membranes of different organisms. To prepare uronic-acid-containing oligosaccharides, uronic acid 6,3-lactones can be employed as they display a fixed conformation and a unique reactivity and stereoselectivity. Herein, we report a highly ß-selective and efficient mannosyl donor based on C-4 acetyl mannuronic acid 6,3-lactone donors. The mechanism of glycosylation is established using a combination of techniques, including infrared ion spectroscopy combined with quantum-chemical calculations and variable-temperature nuclear magnetic resonance (VT NMR) spectroscopy. The role of these intermediates in glycosylation is assayed by varying the activation protocol and acceptor nucleophilicity. The observed trends are analogous to the well-studied 4,6-benzylidene glycosides and may be used to guide the development of next-generation stereoselective glycosyl donors.

Open label trial of tamoxifen in scleroderma.

BACKGROUND: Previous reports have suggested that treatment with the selective estrogen antagonist tamoxifen may be effective in diminishing primary and secondary Raynaud's vasospasm, including cases occurring in the setting of scleroderma. Tamoxifen treatment has also been associated with improvement of retroperitoneal fibrosis and desmoid tumors, conditions also associated with abnormal fibroblast proliferation. Tamoxifen increases production of the immunosuppressive cytokine TGF beta which modulates fibroblast activity. The potential effect of tamoxifen on vascular reactivity and fibrotic lesions raised questions about its utility as a therapeutic agent in scleroderma. OBJECTIVE: To determine the utility of tamoxifen therapy in scleroderma. METHODS: Open label preliminary, prospective, proof of concept study of tamoxifen. RESULTS: Fifteen patients (3 male, 12 female) with scleroderma were enrolled (10 diffuse disease, 5 CREST). Mean age was 55 (34-75) years. Mean duration of scleroderma was 9.3 (1-25) years. Two patients were excluded. For 13 patients, mean duration of treatment was 7 (1.5-32) months. Two of 13 patients treated with tamoxifen experienced transient improvement. They did not appear to have clinical features that identified them as a unique subset. Both patients subsequently relapsed, in one case 12 months, and in the other 24 months after treatment. CONCLUSION: Based on these results, we would not recommend tamoxifen for further large scale studies in scleroderma.

[CT-guided marking of lung lesions before minimally invasive operation]. / CT-gesteuerte Lungenherdmarkierung vor minimal-invasiver Operation.

Video-assisted thoracoscopic surgery (VATS) is an established method for resection of suspicious pulmonary lesions. However, there are problems to detect small subpleural lesions. A procedure for localization of such lesions will be demonstrated. Since may 2000 our experience includes 5 patients (4m, 1f) suffering from solitary pulmonary lesions. In preparation of VATS a CT-guided marking was carried out using both a lasermarker system as well as a special marker system for lung lesions. All 5 procedures were successful. With the laser system the pulmonary nodule was exactly marked and the special wire was placed without any complications. Consequently, the pulmonary nodule was fixed. During video-assisted wedge resection the nodule can be tracted outside. Operating time was reduced in comparison to time consuming search of unmarked lesions. The combined application of CT-guided marking, transthoracic fixation of pulmonary nodule and VATS is recommended preoperatively. It should apply in lesions, which are located subpleural and thoracoscopically not visible.

Comparison of the Vitek Gram-Positive Susceptibility 106 card and the MRSA-screen latex agglutination test for determining oxacillin resistance in clinical bloodstream isolates of Staphylococcus aureus.

The Vitek automated susceptibility testing system with a modified Gram-Positive Susceptibility (GPS) 106 Card (bioMerieux Vitek, Inc., Hazelwood, Mo.) and a rapid slide latex agglutination test (MRSA-Screen; Denka Seiken Co., Ltd., Tokyo, Japan) were evaluated for their ability to detect oxacillin resistance in Staphylococcus aureus. The oxacillin-salt agar screen (OS) test, the reference broth microdilution method, and the detection of the mecA gene by PCR were compared with the commercial products. A total of 200 contemporary (1999) bloodstream infection isolates were collected from the SENTRY Antimicrobial Surveillance Program, representing diverse geographic areas throughout the world. Among the 99 mecA-positive isolates, 3 isolates were found negative by the MRSA-Screen. Another two isolates did not grow on OS plates and had MICs of 0.5 and 2 microg/ml with the Vitek GPS card. All 101 mecA-negative isolates were also found negative by the MRSA-Screen and were categorized as susceptible by the GPS card. Overall, the MRSA-Screen, GPS card, and OS test had sensitivities of 96.9, 98.0, and 98.0% and specificities of 100.0, 100.0, and 98.0%, respectively. MRSA-Screen was a rapid (

[Diagnosis and therapy of laryngitis gastrica]. / Diagnostik und Therapie der Laryngitis gastrica.

We treated 64 patients with the diagnosis of laryngitis gastrica with Antra (Omeprazol) in doses of 10, 20, and 40 mg. To determine the success of the therapy, pH monitoring of the esophagus and hypopharynx, the voice status and measurement of vocal penetrating capacity were used. The results prove that a 20-mg dose of Antra is suitable for the therapy of laryngitis gastrica with a high rate of success. Problems which arose during the investigation, consequent changes of the original concept of the project as well as new aspects and questions which resulted from this are discussed with respect to further investigation.

CT-guided intervention using a patient laser marker system.

To prove the usefulness of a simple laser marker system (LMS) in target definition as well as examination procedure for CT-guided interventions, 130 cases of diagnostic biopsies and lumbal sympathectomies were compared. In 75 cases LMS and in 55 cases a simple crossgrid was used. Taking advantage of the LMS, the parameters of intervention (cutaneous location, length, and angle) can be planned, exactly demonstrated, and it is possible to check the needle position during the whole procedure. Thus, the number of necessary control scans decreased to 30%, and corrections of needle location were reduced to approximately 30%. Moreover, the average target deviation of the needle decreased below 5 mm in 50% of cases, and the duration of interventional procedure was reduced considerably. It can be concluded that LMSs are recommended in CT-guided interventions for quality assurance, dose reduction, and improvement of handling. It will be especially advantageous in cases of small target volume, oblique needle path, and tilted gantry.

Occurrence of single-point gyrA mutations among ciprofloxacin-susceptible Escherichia coli isolates causing urinary tract infections in Latin America.

To detect if isolates susceptible to quinolones already carry mutations in the gyrA and parC genes, we selected 12 ciprofloxacin-susceptible Escherichia coli strains collected from patients with urinary tract infections in Latin America in 1998, as part of ongoing SENTRY Antimicrobial Surveillance Program. The isolates studied exhibited minimal inhibitory concentrations (MICs) for ciprofloxacin between < or = 0.015 microg/mL and 0.5 microg/mL. The molecular characterization of quinolone resistance was determinated by amplification of the gyrA and parC by PCR followed by sequencing of the respective amplicons. We observed that E. coli isolates exhibiting MIC, < or = 0.06 microg/mL for ciprofloxacin did not show mutations in either topoisomerase. On the other hand, all isolates with MIC between 0.12 microg/mL and 0.5 microg/mL demonstrated single mutation in the gyrA gene. The most frequent mutation occurred at position 83, where the amino acid serine was replaced by leucine. No mutations in the parC gene were observed. To preserve the potency and prevent the development of resistance, we suggest that quinolone usage should be rational, especially in the treatment of urinary tract infections, and in the prophylaxis of immunosupressed patient populations.

Activity and spectrum of 22 antimicrobial agents tested against urinary tract infection pathogens in hospitalized patients in Latin America: report from the second year of the SENTRY antimicrobial surveillance program (1998).

The potency and spectrum of various antimicrobial agents tested against 434 bacterial isolates causing urinary tract infection (UTI) in hospitalized patients in Latin America were evaluated. The genotypes of the extended-spectrum beta-lactamase-producing and selected multi-resistant isolates were also evaluated by molecular typing techniques. Escherichia coli (60.4%) was the most common aetiological agent causing UTI, followed by Klebsiella spp. (11.2%) and Pseudomonas aeruginosa (8.3%). In contrast, Enterococcus spp. isolates caused only 2.3% of UTIs. Fewer than 50% of E. coli isolates were susceptible to broad-spectrum penicillins. The resistance rates to ciprofloxacin and the new quinolones were also high among these isolates. The molecular characterization of ciprofloxacin-resistant E. coli showed that most of them have a double mutation in the gyrA gene associated with a single mutation in the parC gene. The Klebsiella pneumoniae isolates studied demonstrated high resistance rates to beta-lactam drugs, including broad-spectrum cephalosporins. The carbapenems were the compounds with the highest susceptibility rate among these isolates (100.0% susceptible) followed by cefepime (91.7% susceptible). Meropenem, imipenem and cefepime were also the most active drugs against Enterobacter spp. Among P. aeruginosa isolates, meropenem (MIC(50), 2 mg/L) was the most active compound, followed by imipenem (MIC(50), 4 mg/L), cefepime (MIC(50), 8 mg/L) and ceftazidime (MIC(50), 16 mg/L). The results presented in this report confirm that bacterial resistance continues to be a great problem in Latin American medical institutions.

Diagnosis, etiology, and therapy of fibromyalgia.

Fibromyalgia is characterized by diffuse pain, multiple tender points, fatigue, and sleep disturbance. Its frequent concurrence with rheumatic diseases modifies the clinical picture of the "primary" disease. This article reviews new information about the etiopathogenesis and treatment of this syndrome.

[24 hour pH monitoring of the hypopharymx]. / 24-h-pH-Metrie des Hypopharynx.

Monitoring of pH of the esophagus is a routine diagnostic procedure, whereas until now pH-monitoring of the hypopharynx has been used only for scientific research. In the present study a critical evaluation scale was used to record the results of 112 patients who underwent pH monitoring to determine possible reflux. Since high refluxes often remain unnoticed clinically, further study is required in certain cases. The extent of reflux in the esophagus may not represent pathological changes in the hypopharynx. In such cases 24-h pH monitoring of the hypopharynx can be a useful diagnostic procedure and may also help detect the pathogenesis of "gastric laryngitis".

[Forgetting of word associations in relation to indicators of emotionality. A possibility for evaluating Freud's concept of repression?]. / Das Vergessen von Wortassoziationen in Abhängigkeit von Indikatoren ihrer Emotionalität. Eine Möglichkeit der Uberprüfung des Freudschen Verdrängungskonzepts?

In replication of the well-known study by Levinger & Clark, 30 subjects were presented a list with 60 words under several conditions. In the first part of the experiment they had to tell the first word which came to mind as a response to the stimuli read by the experimenter. Reaction times and skin conductance reactions (SCRs) during associations were recorded. Immediately afterwards the list was read again with the instruction to recall the associations given before. In part 2 of the study, one week later, subjects had to recall again their first associations; in addition, they scaled the emotionality of the word stimuli. Intraindividual correlations were computed for indices of emotionality (reaction time, SCR, perceived emotionality) and forgetting in both short-term and long-term memory. Associations accompanied by larger electrodermal reaction and showing longer reaction time were more likely to be forgotten both for short and long intervals. This is in line with Freuds concept of repression. However, alternative explanations should also be discussed.

Downregulation of T helper type 1 immune response and altered pro-inflammatory and anti-inflammatory T cell cytokine balance following conventional but not laparoscopic surgery.

BACKGROUND: The clinical advantages of laparoscopic procedures result from a minimized surgical trauma. The present study was performed to investigate immunosupression following laparoscopic operations as compared with open surgery. Our analysis focused on the T cell secretion of cytokines that regulate the critical balance of either T helper type-1 (Th1)- and Th2-mediated immune responses on pro- and antiinflammatory activities. METHODS: In a prospective study, immunological data of 26 patients submitted to laparoscopic cholecystectomy (LCE) and 17 patients undergoing conventional cholecystectomy (CCE) for symptomatic cholecystolithiasis were compared. Patients with acute cholecystitis and patients developing postoperative complications or receiving immunosuppressive medication were excluded. Production of interferon (IFN)-gamma, interleukin (IL)-2, IL-4, tumor necrosis factor (TNF)-alpha, and IL-10 by isolated T cells stimulated by cross-linking of CD3 and CD28 was evaluated preoperatively as well as on postoperative days 1 and 6 or 7. Cytokines were measured by immunoenzymometric assay. RESULTS: IFN-gamma, TNF-alpha, and IL-2 production by T cells decreased significantly by 48.3%, 36.6%, and 36.8%, respectively, on postoperative day 1 after CCE, but not after LCE. These results indicate severe suppression of Th1-type and proinflammatory cytokines after the open operation. In contrast, IL-4 and IL-10 did not show significant changes in either group suggesting that Th2 cell response and anti-inflammatory activity remained normal. CONCLUSIONS: The present study shows that open, but not laparoscopic cholecystectomy is associated with a marked suppression of T lymphocytes functions as indicated by deregulation of both the Th1/Th2 and the pro-/anti-inflammatory cytokine balance. The results therefore suggest that downregulation of Th1 cell-mediated immune response and pro-inflammatory activity of T cells is a hallmark of open, but not laparoscopic surgery.

Use of molecular and reference susceptibility testing methods in a multicenter evaluation of MicroScan dried overnight gram-positive MIC panels for detection of vancomycin and high-level aminoglycoside resistances in enterococci.

Modified MicroScan gram-positive MIC no. 8 panels (PM-8) were analyzed for their improved ability to detect vancomycin resistance (VR) and high-level aminoglycoside resistance (HLAR) in enterococci. A validation study design that utilized selected challenge strains, recent clinical isolates, and reproducibility experiments in a multicenter format was selected. Three independent medical centers compared the commercial panels to reference broth microdilution panels (RBM) and Synergy Quad Agar (QA). Resistance was verified by demonstration of VR and HLAR genes by PCR tests. The study was conducted in three phases. (i) In the challenge phase (CP), two well-characterized sets of enterococci were obtained from the Centers for Disease Control and Prevention; one set contained 50 isolates for VR testing and one contained 48 isolates for HLAR testing. In addition, a set of 47 well-characterized isolates representing diverse geographic areas, obtained from earlier national surveillance studies, was tested at the University of Iowa College of Medicine (UICM). (ii) In the efficacy phase (EP), each laboratory tested 50 recent, unique clinical isolates by all methods. (iii) In the reproducibility Phase (RP), each laboratory tested the same 10 strains by all methods in triplicate on three separate days. All isolates from the EP were sent to the UICM for molecular characterization of vanA, -B, -C1, -C2-3, and HLAR genes. In the CP, the ranking of test methods by error rates (in parentheses; very major and major errors combined, versus PCR results) were as follows: for high-level streptomycin resistance (HLSR), QA (12.0%) > PM-8 (5.2%) > RBM (1.6%); for high-level gentamicin resistance (HLGR), RBM (3.7%) > PM-8 (3.1%) > QA (2.6%); and for VR, RBM = QA (3.0%) > PM-8 (1.2%). In the EP, agreement between all methods and the reference PCR result was 98.0% for HLSR, 99.3% for HLGR, and 98. 6% for VR. In the RP, the percentages of results +/- 1 log2 dilution of the all-participant mode were as follows: for VR, 100% (PM-8), 98.9% (QA), and 90.0% (RBM); for HLSR, 99.6% (RBM), 98.5% (PM-8), and 82.2% (QA); and for HLGR, 99.6% (RBM), 99.3% (PM-8), and 98.1% (QA). The ability of the PM-8 to detect VR and HLAR in enterococci was comparable to those for reference susceptibility and molecular PCR methods and was considered acceptable for routine clinical laboratory use.

Normal T lymphocyte and monocyte function after minimally invasive surgery.

BACKGROUND: The aim of this study was to evaluate immune defense mechanisms after laparoscopic (LCHE) and open cholecystectomy (CHE), particularly with regard to monocyte and T-lymphocyte function. METHODS: In a prospective study, we evaluated the following immunological data from 27 patients (21 women, six men; mean age, 47.2 years) submitted to elective LCHE and 14 patients (seven women, seven men; mean age, 60.8 years) undergoing elective CHE: T-lymphocyte proliferation (stimulated by SEA, SEB, TSST-1 with antigen presentation by patient monocytes), expression of cell surface molecules on monocytes (HLA-DR, CD80, L-Selectin), CD4+ T lymphocytes (HLA-DR, CD25, ICAM-1, L-Selectin), and granulocytes (L-Selectin). Blood samples were collected preoperatively and on postoperative days 1 and 6-7. Statistical analysis was performed using the Mann-Whitney U test for paired samples. RESULTS: HLA-DR on monocytes significantly decreased after LCHE during the early postoperative course but returned to preoperative levels within 1 week. After CHE, significant downregulation of HLA-DR expression persisted throughout the whole observation period. This decrease, however, did not alter the antigen-presenting capacity of monocytes in both groups. Moreover, the APC-independent proliferative capacity of T lymphocytes was unimpaired. CD25 expression was significantly increased on postoperative day 1 after CHE but not after LCHE. Expression of HLA-DR, ICAM1, and L-Selection on CD4+ T cells was not altered in either group. CD80 on monocytes and L-Selection on monocytes and granulocytes remained unchanged after both procedures. CONCLUSIONS: HLA-DR surface molecules on monocytes that are required for antigen presentation were significantly decreased in both groups; they returned to normal within 1 week after LCHE but not after CHE. However, the antigen-presenting capacity for monocytes remained normal in both groups. T-cell stimulation, reflected by an increase of CD25 expression, was observed only after CHE, not after LCHE. We therefore conclude that LCHE interferes less with immune defense than CHE; however, the clinical relevance of the changes noted after the open operation remains to be determined.

The connection between chronic fatigue syndrome and neurally mediated hypotension.

Research from several groups of investigators indicates that some patients with chronic fatigue syndrome have abnormal vasovagal or vasodepressor responses to upright posture. If confirmed, these findings may explain some of the symptoms of chronic fatigue syndrome. There is also speculation that neurally mediated hypotension may be present in fibromyalgia. This article discusses the original research in this area, the results of follow-up studies, and the current approach to treating patients with chronic fatigue syndrome in whom neurally mediated hypotension is suspected.

Staphylococcus aureus and coagulase-negative staphylococci from blood stream infections: frequency of occurrence, antimicrobial susceptibility, and molecular (mecA) characterization of oxacillin resistance in the SCOPE program.

Staphylococci are major causes of nosocomial blood stream infection. The recently completed SCOPE Surveillance Program found that coagulase-negative staphylococci (CoNS) and Staphylococcus aureus were the first and second most common etiologic agents, respectively, causing nosocomial blood stream infection in the USA. The frequency of oxacillin resistance was 68% among 1553 strains of CoNS and 26% among 787 strains of S. aureus in this study. Extended susceptibility profiles were generated for a subset of 150 S. aureus and 300 CoNS against 16 antimicrobial agents. Oxacillin-susceptible strains of both CoNS and S. aureus were uniformly susceptible to beta-lactam agents with the exception of ampicillin and penicillin. Oxacillin-susceptible S. aureus were also highly susceptible to the fluoroquinolones, aminoglycosides, and trimethoprim/sulfamethoxazole. The oxacillin-susceptible CoNS were less susceptible to these agents, and only glycopeptides were reliably active against oxacillin-resistant strains. PCR detection of the mecA gene was used to scrutinize current NCCLS interpretive breakpoint MICs for determining susceptibility or resistance to oxacillin. We found complete concordance between the presence or absence of mecA and the NCCLS oxacillin interpretive breakpoint categories for S. aureus. In contrast, the NCCLS breakpoints for oxacillin significantly underestimate the degree of true oxacillin resistance among CoNS. Using the presence of mecA as the reference standard, we detected 15.7% false susceptibility to oxacillin using a MIC susceptible breakpoint concentration of < or = 2 micrograms/mL. Lowering the oxacillin MIC breakpoint to < or = 0.25 microgram/mL for CoNS would greatly improve the accuracy of the MIC test performance. We found that both the current oxacillin disk test and the 30-microgram ceftizoxime disk test functioned quite well in predicting those strains of CoNS that contain mecA. These studies have demonstrated both a high level of antimicrobial resistance among nosocomial blood stream isolates of staphylococci as well as significant problems with the current NCCLS breakpoints for oxacillin when testing CoNS.