Novel non-covalent thrombin inhibitors incorporating P(1) 4,5,6,7-tetrahydrobenzothiazole arginine side chain mimetics

The design, synthesis and biological activity of a series of novel non-covalent D-Phe-Pro-Arg motif-based thrombin inhibitors incorporating 4,5,6,7-tetrahydrobenzothiazol-2-amine as a novel arginine surrogate are described. Compound 9, the most potent in the series of thrombin inhibitors, exhibited an in vitro K(i) of 128 nM and 342-fold selectivity against trypsin. The binding mode of this novel class of thrombin inhibitors in the enzyme active site, based on the X-ray crystal structure of compound 9 co-crystallized with human alpha-thrombin, is discussed.     

Fibrillary noncongophilic renal and extrarenal deposits: a report on 10 cases

Cases in which glomerular deposits of Congo red negative amyloid-like fibrils were demonstrated by electron microscopic identification are included in this study. In the 1,266 kidney biopsies studied, there were 9 biopsies from 8 patients with fibrillary glomerulonephritis and 2 biopsies from 2 patients with systemic lupus. In 1 case of fibrillary glomerulonephritis (FGN), autopsy was performed. Electron microscopic examination showed glomerular (100%) and extraglomerular (60%) fibrillary deposits in the biopsy samples of patients with FGN and also in patients with systemic lupus. In the autopsy case, similar fibrillary deposits were demonstrated in the kidney, pancreas, spleen, lungs, and liver. The diameter of the fibrils, which were arranged similarly in all cases, varied from 8 to 27 nm individually, the length being about 1.5 μm. The authors speculate that extraglomerular kidney fibrillary deposits concurrent with the same type of deposits in other organs suggests systemic manifestation of FGN.     

Possibility of application of new pneumococcal conjugate vaccines in children in Slovenia

The emergence of pneumococcal strains resistant to penicillin caused a lot of problems in the therapy of invasive diseases, and added new dimensions to the role of immunisation. In addition to the currently available 23-valent pneumococcal polysaccharide vaccine (PPV) and a new 7-valent conjugate vaccine (PCV) (Prevnar, Wyeth Lederle), two new conjugate vaccines—a 9- and a 11-valent—are being developed. So far, the choice of most appropriate vaccines has depended on the established prevalence of serotypes causing invasive diseases and their antibiotic resistance in the Slovene children population. Between 1993 and 2001, 263 invasive pneumococcal strains isolated from children with invasive diseases were typed. During the period 1998–2001, the same 161 invasive strains were tested for their antibiotic sensitivity. Streptococcus pneumoniae was identified as the major cause of invasive bacterial diseases in the Slovene children population, especially in children under 4 years of age. Distribution by age groups showed the highest incidence in children aged 0–1 years. The predominant serotypes in all age groups were serotypes 14, 1, 19F, 23F, 6B, 18C and 6A. The distribution of penicillin-intermediate and penicillin-resistant strains showed the predominance of serotypes 23F, 14 and 19F. As concerns infection with S. pneumoniae serotypes, we have proved that children aged less than 5 years are more likely to be infected with penicillin-nonsusceptible or intermediate susceptible strains than older children. The 7-valent conjugate vaccine covers 74% of invasive strains in toddlers, but is less effective in older children.

We can conclude that the 9-valent vaccine formulation is optimal for our country, but further cost-effectiveness analysis must be done for recommendation of wide use.

At that moment it is reasonable to use the 7-valent conjugate vaccine for children with chronic cardiovascular, pulmonary, urinary and liver diseases, with asplenia, neoplasmia, diabetes, meningomyelocoele, before or after bone marrow transplantation and in cases of immunodeficiency.     

High D-dimer levels predict cardiovascular events in patients with chronic atrial fibrillation during oral anticoagulant therapy

Atrial fibrillation (AF) is associated with hemostatic abnormalities and increased risk of thrombotic cardiovascular events even during oral anticoagulant therapy (OAT). The aim of our study was to evaluate the predictive value of hemostatic markers for the risk of major cardiovascular events during OAT. The study group comprised 113 patients with chronic AF (70.2 +/- 5.4 years old, 60% men), referred for OAT. Established clinical risk factors and levels of prothrombin fragment 1+2 (F1+2), thrombin-antithrombin complexes (TAT), D-dimer, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor 1 (PAI-1) antigen and activity, before and during OAT (after 3.9 +/- 0.7 months; INR 2.57 +/- 0.57) were determined. In all patients OAT significantly suppressed levels of F1+2 by 67%,TAT by 30% and D-dimer by 48% (all p <0.001). During an average follow-up of 44 months 22/111 (20%) patients suffered a combined cardiovascular event (stroke, myocardial infarction, peripheral vascular occlusion or vascular death). Patients with cardiovascular events were significantly older, had more frequent heart failure/systolic dysfunction and had significantly increased levels of D-dimer at entry (63 vs 39 ng/mL, p = 0.005) and during OAT (33 vs 18 ng/mL, p = 0.002), and of t-PA antigen at entry (14.3 vs 10.9 ng/mL, p = 0.02) and during OAT (15.0 vs 11.2 ng/mL, p = 0.05) (all values are medians). In multivariate Cox proportional hazard models, heart failure/systolic dysfunction (hazard ratio 2.91; 95% CI 1.17-7.26; p = 0.02), high levels of D-dimer on OAT (top vs. lower two quartiles) (hazard ratio 4.78, 95% CI 1.39-16.41; p = 0.01) and t-PA antigen levels (continuous variable) (hazard ratio 1.09; 95% CI 1.01-1.17; p = 0.02) were significantly associated with combined cardiovascular events. In conclusion, high levels of D-dimer and t-PA antigen during OAT are significant predictors of combined cardiovascular events in AF patients and, on this basis, could be useful additional markers of cardiovascular risk in such patients.     

Distribution of some activating <Emphasis Type="Italic">KRAS</Emphasis> and <Emphasis Type="Italic">BRAF</Emphasis> mutations in Slovene patients with colorectal cancer

Numerous clinical studies have shown that anti-EGFR therapies are effective only in a subset of patients with colorectal cancer. Even though mutations in the KRAS gene have been confirmed as negative predictors of the response to EGFR-targeted therapies, not all KRAS wild-type (wt-KRAS) patients will respond to treatment. Recent studies have demonstrated that additionally wild-type BRAF (wt-BRAF) genotype is required for response to panitumumab or cetuximab, suggesting that BRAF genotype criteria should be used together with KRAS genotype for selecting the patients who are about to benefit from the anti-EGFR therapy. In this study, 239 samples obtained from 215 patients with metastatic colorectal cancer were tested for the presence of the seven most common mutations in the KRAS gene and the V600E mutation in the BRAF gene. Among the tested patients, 53.8% of patients had wt-KRAS genotype and 46.2% were KRAS mutants. Around five percent (5.1%) of the tested patients bore the V600E mutation in BRAF gene. All the patients showing to have the V600E mutation in BRAF were wt-KRAS. The concordance of KRAS and BRAF mutational status between primary and metastatic tumor tissue samples was 100%. We have shown that the proportions of mutated and non-mutated KRAS in Slovene patients, as well as the proportion of V600E mutations in BRAF is similar to genotyping results reported by other authors. The tested seven KRAS mutations on codons 12 and 13 were mutually exclusive with the V600E mutation in the BRAF gene. Summing up the results about the KRAS and the BRAF mutation carriers from our study, the portion of potentially non-responsive patients for the anti-EGFR treatment is 51.3%.     

Synbiotics, prebiotics, glutamine, or peptide in early enteral nutrition: a randomized study in trauma patients

BACKGROUND: Since the hepatosplanchnic region plays a central role in development of multiple-organ failure and infections in critically ill trauma patients, this study focuses on the influence of glutamine, peptide, and synbiotics on intestinal permeability and clinical outcome. METHODS: One hundred thirteen multiple injured patients were prospectively randomized into 4 groups: group A, glutamine; B, fermentable fiber; C, peptide diet; and D, standard enteral formula with fibers combined with Synbiotic 2000 (Synbiotic 2000 Forte; Medifarm, Sweden), a formula containing live lactobacilli and specific bioactive fibers. Intestinal permeability was evaluated by measuring lactulose-mannitol excretion ratio on days 2, 4, and 7. RESULTS: No differences in days of mechanical ventilation, intensive care unit stay, or multiple-organ failure scores were found between the patient groups. A total of 51 infections, including 38 pneumonia, were observed, with only 5 infections and 4 pneumonias in group D, which was significantly less than combined infections (p = .003) and pneumonias (p = .03) in groups A, B, and C. Intestinal permeability decreased only in group D, from 0.148 (0.056-0.240) on day 4 to 0.061 (0.040-0.099) on day 7; (p < .05). In group A, the lactulose-mannitol excretion ratio increased significantly (p < .02) from 0.050 (0.013-0.116) on day 2 to 0.159 (0.088-0.311) on day 7. The total gastric retention volume in 7 days was 1150 (785-2395) mL in group D, which was significantly more than the 410 (382-1062) mL in group A (p < .02), and 620 (337-1190) mL in group C (p < .03). CONCLUSIONS: Patients supplemented with synbiotics did better than the others, with lower intestinal permeability and fewer infections.     

Evaluation of two commercial amplification assays for detection ofMycobacterium tuberculosis complex in respiratory specimens

Summary To evaluate the usefulness of two standardized commercially available amplification assays for the detection ofMycobacterium tuberculosis: Amplicor® test (Roche) and MTD-Amplified direct test (Gen-Probe) a total of 281 respiratory specimens from 198 patients with symptoms of pulmonary diseases were examined and compared with conventional methods. Fifty-seven specimens were positive and 218 negative by both amplification assays. Three specimens were reactive by Amplicor® only, and three by MTD only. In comparison with culture, the sensitivity, specificity, positive predictive value and negative predictive value were 96.0, 94.8, 80.0, and 99.1%, respectively, for the Amplicor® test; the corresponding values were 94.0, 94.4, 78.3, and 98.6%, respectively, for the MTD. However, when 28 specimens from 14 patients on antituberculous therapy were excluded the improvement in PPV and specificity of both assays was obtained. In conclusion, both commercially available amplification tests are almost equally sensitive and specific and are suitable for the implementation in daily routine work in the specialized clinical laboratories.

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Bewertung zweier kommerzieller Amplifikationsassays für den Nachweis vonMycobacterium tuberculosis complex in Proben aus den Atemwegen

Zusammenfassung Um die Brauchbarkeit zweier standardisierter, kommerziell erhältlicher Amplifikationsassays für den Nachweis vonMycobacterium tuberculosis (Amplicor® Test (Roche und MTD Amplified Direct Test (Gen-Probe) zu beurteilen, wurden insgesamt 281 Proben aus den Atemwegen von 198 Patienten mit Symptomen einer Lungenerkrankung vergleichend mit konventionellen Methoden untersucht. 57 Proben waren positiv und 218 in beiden Amplifikationsassays negativ. Drei Proben waren nur mit Amplicor® positiv, drei nur mit MTD. Im Vergleich zur Kultur ergab sich eine Sensitivtät von 96,0%, Spezifität von 94,8%, ein positiver prädiktiver Wert von 80,0% und ein negativer prädikativer Wert von 99,1% für den Amplicor® Test. Die entsprechenden Werte für den MTD-Test sind 94,0, 94,4, 78,3 und 98,6%. Wenn man jedoch 28 Proben von 14 Patienten, die unter tuberkulostatischer Therapie standen, ausschließt, erhöhen sich der positive prädiktive Wert und die Spezifität bei beiden Testsystemen. Es folgt, daß beide kommerziell erhältlichen Amplifikationstests an Sensitivität und Spezifität nahezu gleich sind und sich für die Anwendung in der täglichen Routinearbeit in klinischen Speziallabors eignen.

     

Influence of hormonal stimulation on in vitro fertilization/embryo transfer outcome

OBJECTIVE: To compare efficacy and efficiency of ovarian stimulation therapy. STUDY DESIGN: Retrospective study compares ovarian response as number of retrieved oocytes, fertilization rates, endometrial patterns, number of pregnancies and pregnancy rates to different stimulation protocols. RESULTS: The least number of cancelled cycles was in long protocols with buserelin. There was no difference in overall number of retrieved oocytes between the rFSH and HMG protocols, but 75% of the patients undergoing both protocols had higher number of oocytes after rFSH. The highest pregnancy rate (35.13%) was with rFSH. There was no statistical correlation between endometrial pattern and type of protocol used. Data showed the 9 mm cut-off value for endometrial thickness, and RI = 0.58 for subendometrial blood flow between the pregnant and non-pregnant group of patients. Nitriderm patches significantly decreased (P < 0.05) subendometrial RI of the patients with impaired uterine perfusion, increased endometrial thickness and achieved better morphology. CONCLUSIONS: These findings demonstrate that rFSH alone and in long protocol gives better results in wide patient population. Nitriderm patches seem to have good impact on pregnancy rate, but further studies are necessary before making any statements.