Four variants of the Citrobacter freundii AmpC-Type cephalosporinases, including novel enzymes CMY-14 and CMY-15, in a Proteus mirabilis clone widespread in Poland

Twenty-nine Proteus mirabilis isolates from 17 Polish hospitals were analyzed. The isolates were resistant to a variety of antimicrobials, and their patterns of resistance to beta-lactams resembled those of the constitutive class C cephalosporinase (AmpC) producers. Indeed, beta-lactamases with a pI of approximately 9.0 were found in all of the isolates, and they were subsequently identified as four AmpC-type cephalosporinases, CMY-4, -12, -14, and -15, of which the two last ones were novel enzyme variants. The enzymes were of Citrobacter freundii origin and were closely related to each other, with CMY-4 likely being the evolutionary precursor of the remaining ones. The bla(CMY) genes were located exclusively in chromosomal DNA, within EcoRI restriction fragments of the same size of approximately 10 kb. In the CMY-12- and -15-producing isolates, an additional fragment of approximately 4.5 kb hybridized with the bla(CMY) probe as well, which could have arisen from a duplication event during the evolution of the genes. In all of the isolates, the ISEcp1 mobile element, which most probably is involved in mobilization of the C. freundii ampC gene, was placed at the same distance from the 5' ends of the bla(CMY) genes, and sequences located between them were identical in isolates carrying each of the four genes. These data suggested that a single chromosome-to-chromosome transfer of the ampC gene from C. freundii to P. mirabilis could have initiated the spread and evolution of the AmpC-producing P. mirabilis in Poland. The hypothesis seems to be confirmed by pulsed-field gel electrophoresis typing, which revealed several cases of close relatedness between the P. mirabilis isolates from distant centers and showed an overall similarity between the majority of the multiresistant isolates.     

Prognostic significance of inverse spatial QRS-T angle circadian pattern in myocardial infarction survivors

Background

We investigated the predictive value of the spatial QRS-T angle (QRSTA) circadian variation in myocardial infarction (MI) patients.

Methods

Analyzing 24-hour recordings (SEER MC, GE Marquette) from 151 MI patients (age 63 ± 12.7), the QRSTA was computed in derived XYZ leads. QRS-T angle values were compared between daytime and night time. The end point was cardiac death or life-threatening ventricular arrhythmia in 1 year.

Results

Overall, QRSTA was slightly higher during the day vs. the night (91° vs. 87°, P = .005). However, 33.8% of the patients showed an inverse diurnal QRSTA variation (higher values at night), which was correlated to the outcome (P = .001, odds ratio 6.7). In multivariate analysis, after entering all factors exhibiting univariate trend towards significance, inverse QRSTA circadian pattern remained significant (P = .036).

Conclusion

Inverse QRSTA circadian pattern was found to be associated with adverse outcome (22.4%) in MI patients, whereas a normal pattern was associated (96%) with a favorable outcome.     

Bone mineral density and bone turnover in relation to serum leptin, α-ketoglutarate and sex steroids in overweight and obese postmenopausal women

Objective Recent studies have shown that parallel changes in body weight and bone mass can be partially mediated via circulating leptin. Therefore, among the hormones involved in bone and mineral metabolism, such as oestrogens, testosterone and parathormone, leptin has recently become a subject of considerable interest. The aim of this study was to assess associations between leptin, E₂, testosterone, dehydroepiandrosterone sulphate (DHEA‐S), SHBG, α‐ketoglutaric acid (AKG) and bone mineral density (BMD) and bone turnover markers in overweight and obese postmenopausal women. Design Eighty healthy, postmenopausal Caucasian women were studied. BMD of the lumbar spine (L₂–L₄) and femoral neck regions were examined using the dual X‐ray absorptiometry (DXA) method. Associations were evaluated in stepwise multiple regression analysis, including information on the possible confounders and effect modifiers, for example, age, years since menopause, height and weight. Results Femoral neck BMD was positively correlated with weight (r = 0·52, P < 0·000001), body mass index (BMI) (r = 0·48, P < 0·000006), hipline (r = 0·48, P < 0·00006), waistline (r = 0·45, P < 0·00002) and DHEA‐S (r = 0·36, P < 0·0008). Correlations of E₂, SHBG, testosterone and leptin, as well as biochemical markers of bone turnover with L₂–L₄ and femoral neck BMD were not found. In the whole study group, significant predictors of L₂–L₄ BMD were BMI (β = 0·35, P < 0·01) testosterone (β = 0·27, P < 0·05) and osteocalcin (OC) (β = 0·22, P < 0·05) (R² = 0·23), while predictors of femoral neck BMD were BMI (β = 0·42, P < 0·001), testosterone (β = 0·24, P < 0·05), E₂ (β = 0·19, P < 0·05), as well as osteocalcin (β = 0·20, P < 0·05) (R² = 0·41). In the subgroup with BMI 30–39·9, the significant predictors of both L₂–L₄ and femoral neck BMD were testosterone (β = 0·32, P < 0·05, R² = 0·19; β = 0·33, P < 0·05, R² = 0·29) and osteocalcin (β = 0·34, P < 0·05, R² = 0·19; β = 0·45, P < 0·01, R² = 0·29). In the subgroup with waist : hip ratio (WHR ≥ 0·85, the predictor of L₂–L₄ BMD was E₂ (β = 0·38, P < 0·05) (R² = 0·21), whereas the predictors of femoral neck BMD were BMI (β = 0·29, P < 0·05) and testosterone (β = 0·35, P < 0·01) (R² = 0·36). Conclusion The main endocrine variable predicting lumbar spine BMD in overweight and obese postmenopausal females was testosterone, while the main determinants of femoral neck BMD were both testosterone and E₂. No effect was found of serum leptin on examined indicators of bone status.     

Serum B-type natriuretic peptide levels on admission predict not only short-term death but also angiographic success of procedure in patients with acute ST-elevation myocardial infarction treated with primary angioplasty

Background

B-type natriuretic peptide (BNP) levels are predictive of short-term death in patients with acute coronary syndromes. Few data are available for BNP levels obtained on admission in patients with acute ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI).

Methods

Blood samples for BNP estimation, obtained on admission in 126 consecutive patients (mean age, 58.8 ± 10.7 years) with STEMI, were measured at the bedside by using a simple point-of-care test in a 15-minute period before PCI. Follow-up up to 42 days was performed.

Results

A baseline BNP value of 331 pg/mL had a sensitivity of 87.9% and a specificity of 90% for predicting death in a follow-up study. There was no difference in subgroups by median BNP (100 pg/mL) in Thrombolysis In Myocardial Infarction (TIMI) flow grade 3 before PCI, although higher BNP levels were observed among patients with TIMI <3 after PCI than among those with TIMI 3 (356.7 ± 350.8 vs 144.9 ± 191.2 pg/mL; P < .0001). In multivariate logistic regression analysis, admission BNP was the independent predictor for the following: death (odds ratio [OR], 16.3; 95% confidence interval [CI], 1.4 to 186.7; P = .03), TIMI grade <3 after PCI (OR, 3.4; 95% CI, 1.2 to 9.6; P = .02), and the no-reflow phenomenon (OR, 6.2; 95% CI, 1.7 to 23; P = .007) after adjusting for other variables.

Conclusions

BNP levels obtained on admission are a powerful, independent predictor of short-term death and angiographic success after PCI in patients with STEMI. The no-reflow phenomenon may be predicted in STEMI on the basis of high serum BNP values on admission.