Integron-mediated ESBL resistance in rare serotypes of Escherichia coli causing infections in an elderly population of Israel

OBJECTIVES: To identify and characterize the aetiology of an outbreak of extra-intestinal multidrug-resistant Escherichia coli infections in elderly patients in Israel. METHODS: Extended-spectrum beta-lactamase (ESBL)-producing clinical isolates of E. coli from extra-intestinal sources were tested for susceptibility to non-beta-lactam drugs, and their serotypes were determined. Restriction enzyme digestion, followed by PFGE of DNA purified from isolates, was used to classify the phylogenetic relationship between them. Plasmid DNA from five isolates of different serotypes was used to transform an E. coli laboratory strain. The plasmids were partially sequenced. RESULTS: E. coli isolates from 86 patients, mostly elderly, were shown to be positive for inhibitor-susceptible ESBLs, and more resistant to cefotaxime than to ceftazidime. Ninety-six per cent of ESBL producers were also resistant to gentamicin, and 100% to trimethoprim/sulfamethoxazole and ciprofloxacin. All isolates belonged to one of five serotypes. PFGE analysis of purified DNA yielded 17 profiles. Sequencing of plasmids isolated from the transformants identified sul1, aac(6')-Ib and bla(CTX-M-2). These genes were embedded in an integron, InS21. CONCLUSIONS: Extra-intestinal infections with ESBL-producing E. coli of different serotypes and probably mixed clonality showed a surprising homogeneity in resistance profiles, with 100% being co-resistant to ciprofloxacin and trimethoprim/sulfamethoxazole, and 96% to gentamicin. Plasmid DNA from three isolates from different serotypes contained integron InS21, previously demonstrated in Salmonella enterica from Argentina. This is the first molecular identification of an ESBL gene and integron in Israel or neighbouring geographical areas.     

Human VIP-alpha: an emerging biologic response modifier to treat primary pulmonary hypertension

Primary pulmonary hypertension (PPH) is a rare life-threatening disorder of unknown etiology manifested by chronic elevation of pulmonary arterial pressure. Given that pulmonary vasoconstriction, endothelial and vascular smooth muscle cell proliferation and in situ thrombosis contribute appreciably to the evolution of PPH, treatment with vasodilators, antiproliferative drugs and anticoagulants, alone or in combination, constitute the pharmacologic standard of care. To this end, long-term administration of oral calcium channel blockers, prostacyclin analogs by various routes and oral endothelin-1 receptor antagonists, alone or in combination, is efficacious in treating patients with PPH. Unfortunately, efficacy is hampered by poor stability, delivery and bioavailability, and by systemic toxicity. Hence, there is an ongoing need to develop and test new drugs to treat patients with PPH. To address this issue, a novel, targeted, long-acting, biocompatible and safe sterically stabilized liposomal and micellar formulation of human vasoactive intestinal peptide (VIP) was developed and tested for human use: the 28-amino acid pleiotropic biologic response modifier, human VIP-alpha. The long-lasting salutary effects of phospholipid-associated VIP on vasomotor tone and arterial pressure were expressed at low concentrations solely in diseased animals and were independent of its route of administration. Thus, the author proposes that human VIP-alpha could be developed as a safe long-acting drug to treat patients with PPH.     

Low pilot exposure to pyrethrin during ultra-low-volume (ULV) aerial insecticide application for control of adult mosquitoes

Pilot exposure to pyrethrin was monitored after 2 aerial applications of a ultra-low-volume (ULV) pyrethrin insecticide for the control of adult mosquitoes. Pyrethrin exposure was estimated by measuring the excretion in urine of a common metabolite, trans-chrysanthemumdicarboxylic acid, of the natural pyrethrin mixture. Pyrethrin exposure estimated by total daily urine volume was well correlated (R2 = 0.8) with exposure estimated by the creatinine-adjusted volume of combined workday urine voids, indicating that a postapplication spot urine sample would be sufficient to measure pyrethrin exposure. Pilot exposure to pyrethrin was very low after both insecticide applications. The highest exposure was found on day 1, with a dose of 2.05 microg pyrethrin equivalents/day or a dosage of 0.03 microg pyrethrin equivalents/kg/day. These exposure rates represent approximately 1/2,800,000th of the low observed adverse effect level and 1/1,000th of the acceptable daily intake for pyrethrin. The aerial application of ULV pyrethrin insecticide for the control of adult mosquitoes does not result in undue exposure to a pilot who is trained and certified to conduct such control operations.     

Cardiovascular adaptations in rats submitted to a resistance-training model

1. The present study sought to evaluate cardiovascular adaptations, such as blood pressure (BP), heart rate (HR) and cardiac hypertrophy, to resistance training (RT) in a rat model. 2. The training protocol consisted of four sets of 10-12 repetitions of the squat exercise performed at 65-75% of one repetition maximum (1RM) over 4 weeks. Animals were randomly divided into three groups: control (n = 8, CO), electrically stimulated (n = 8, ES) and trained (n = 8, TR; also electrically stimulated). Blood pressure and HR were measured by a direct method in conscious rats after the training period. 3. All groups began with similar 1RM and 1RM/bodyweight (BW) ratio, however, at the end of the protocol only the TR group was different from the beginning (56% and 50%, respectively; both P < 0.01). The CO and ES groups had similar values for cardiac chambers weight/BW ratio, HR and diastolic, systolic and mean BP. Left ventricular hypertrophy (LVH) determined by the left ventricle (LV) weight/BW ratio was increased in the TR group (12%) when compared to CO (P < 0.01) or ES groups (P < 0.01). No changes were found in the weights of the atrium or right ventricle. Diastolic (14%) and mean BP (13%) were lower in the TR group (P < 0.05), whereas systolic BP and HR remained unchanged. 4. Collectively these results demonstrate that the rat RT model used is associated with significant development of cardiac hypertrophy and lowering of resting BP. These cardiovascular adaptations seem to a result of the training exercise and not influenced by stress since circulating catecholamine levels and adrenal gland weights remained unchanged in all groups.     

Chronic beta-adrenoceptor stimulation and cardiac hypertrophy with no induction of circulating renin

The hemodynamic and cardiac effects of isoproterenol were examined in rats submitted to chronic salt loading (1% NaCl as drinking water) to prevent activation of the systemic renin–angiotensin system. Isoproterenol treatment for 1 week resulted in 36% and 44% (P < 0.05) increase in left ventricle mass in both control and chronic salt loading rats and induction of cardiac angiotensin-converting enzyme activity and expression (P < 0.05) with no changes in serum angiotensin-converting enzyme. Plasma renin activity decreased significantly with chronic salt loading and failed to increase by isoproterenol treatment, whereas it increased 2.33 fold (P < 0.05) in animals kept on regular chow. Isoproterenol treatment leads to transient increase in heart rate and cardiac output while blood pressure remained unchanged. Altogether, these data provide evidence that isoproterenol induced hypertrophy is associated with cardiac induction of angiotensin-converting enzyme and daily transient hemodynamic overload even in the absence of systemic activation of renin–angiotensin system.     

Evidence for two atypical conformations of beta-adrenoceptors and their interaction with Gi proteins

In this study, we investigated whether the responses of right atria from sinoaortic denervated rats to CGP12177 (4(3-t-butylamino-2-hydroxypropoxy benzidimidazole-2 one, hydrochloride)), isoprenaline and norepinephrine desensitized in parallel and whether CGP12177 interacted with distinct conformations of beta-adrenoceptors. Right atria from rats 48 h after sinoaortic denervation were subsensitive to isoprenaline, norepinephrine and CGP12177. One week after sinoaortic denervation, the sensitivity to CGP12177 had recovered whereas the responses to isoprenaline and norepinephrine were still subsensitive, suggesting that the binding sites for these molecules showed independent behavior. In atria from 48 h sinoaortic-denervated rats, propranolol or 3 microM CGP20712A (2-hydroxy-5(2-((2-hydroxy-3-(4-((methyl-4-trifluormethyl)1H imidazole-2-yl)-phenoxypropyl) amino) ethoxy)-benzamide monomethane sulphonate)) blocked the responses to 10 nM-1 microM CGP12177 and steepened the curves. The concentration-response curves to CGP12177 in the presence of ICI118,551 (erythro-DL-1(-methylindan-4-yloxy)-3-isopropylamino-butan-2-ol) were biphasic, suggesting that CGP12177 interacted with at least two conformations of beta-adrenoceptors that showed negative cooperativism, one acting through beta(2)-adrenoceptor-Gi and the other via beta(1)-adrenoceptor-Gs. This hypothesis was confirmed in right atria from sinoaortic-denervated rats treated with pertussis toxin.     

Clozapine induces oxidative stress and proapoptotic gene expression in neutrophils of schizophrenic patients

The present study examined cellular effects of the atypical antipsychotic drug clozapine on blood cells of treated patients with and without clozapine-induced agranulocytosis (CA). Blood from one patient who commenced clozapine treatment was examined at weekly intervals for 128 days. Olanzapine-treated (n = 5) and polymedicated (n = 14) schizophrenic patients, as well as healthy subjects (n = 19) and septic shock patients (n = 8), were studied for comparison. We observed dramatically increased numbers of native neutrophils stained for superoxide anion production (P < or = 0.005, n = 10) and significantly elevated expression levels of the proapoptotic genes p53 (P < or = 0.020), bax alpha (P < or = 0.001), and bik (P < or = 0.002) in all tested non-CA patients (n = 19) and CA patients (n = 4). In non-CA patients, the expression of these genes did not correlate to the percentage of apoptotic neutrophils (2.0% +/- 1.3%), but in CA patients about 37% of the neutrophils show morphologic signs of apoptosis (P < or = 0.001). Under G-CSF therapy of CA, the number of apoptotic neutrophils and the expression of the proapoptotic genes decreased significantly. In conclusion, high production of reactive oxygen species in neutrophils of clozapine-treated patients, together with increased expression of proapoptotic genes, suggests that neutrophils are predisposed to apoptosis in schizophrenic patients under clozapine therapy. The correlation between drug and proapoptotic markers was highest for clozapine and bax alpha as well as superoxide anion radicals. This indicates oxidative mitochondrial stress in neutrophils of clozapine-treated patients which probably contributes to the induction of apoptosis and sudden loss of neutrophils and their precursors in CA patients.     

Burden of medical illness in drug- and alcohol-dependent persons without primary care

Little is known about the frequency, severity, and risk factors for disease in drug- and alcohol-dependent persons without primary medical care. Our aims are to assess the burden of medical illness, identify patient and substance dependence characteristics associated with worse physical health, and compare measures of illness burden in this population. This was accomplished through a cross-sectional study among alcohol-, heroin- or cocaine-dependent persons without primary medical care who were admitted to an urban inpatient detoxification unit. The mean age of these patients was 35.7 (SD 7.8) years; 76% were male and 46% were Black. Forty-five percent reported being diagnosed with a chronic illness, and 80% had prior medical hospitalizations. The mean age-adjusted SF-36 Physical Component Summary (PCS) score was lower than the general U.S. population norm (44.1 vs 50.1; p<0.001). In multivariable analysis, female gender (adjusted mean change in PCS score: -3.71 points, p=.002), problem use of hallucinogens (-3.51, p=0.013), heroin (-2.94, p=0.008), other opiates (-3.20, p=.045), living alone (-3.15, p=.023), having medical insurance (-2.26, p=0.014) and older age (-.22 points per year, p=0.001) were associated with worse health. From these data, it seems that alcohol- and drug-dependent persons without primary medical care have a substantial burden of medical illness compared to age- and gender-matched U.S. population controls. While the optimal measure of medical illness burden in this population is unclear, a variety of health measures document this medical illness burden in addicted persons.     

Predicting developmental outcomes in very preterm infants: validity of a neonatal neurobehavioral assessment

Aim: This study explored inter‐rater reliability, discriminative, construct and predictive validity of the Neurobehavioral Assessment of the Preterm Infant (NAPI) in a gestational‐age‐based cohort. Methods: The NAPI was conducted at 35 weeks post‐menstrual age for 170 infants born <32 weeks. Cognitive and motor development was assessed at 2 years using the Mental Development Index (MDI) and Psychomotor Development Index (PDI) of Bayley Scales of Infant Development‐II for 159 infants. Results: Only NAPI motor and irritability scores were significantly different between very (29–3 w) and extremely preterm (<28 w) infants. Results regarding construct validity were variable: there were weak correlations between NAPI motor scores and gestational age (r = ?0.23; p = 0.003), days in NICU (r = ?0.24; p = 0.001); NAPI alertness scores and days in NICU (r = ?0.16; p = 0.037); and NAPI irritability scores and gestational age (r = 0.21; p = 0.006). There were no significant associations with other markers of adverse outcome. Only NAPI irritability scores were correlated with MDI scores (r = ?0.16; p = 0.040) but accounted for little additional variance after adjustment for neonatal factors (ΔR² = 0.035; p = 0.012). Conclusion: We found little evidence of the utility of the NAPI as a measure of short‐term neurobehavioural function or for predicting neurodevelopmental outcomes in very preterm infants. It may have greater predictive power when used serially to detect delayed neurobehavioural maturation.     

Surgical management of Wilms tumor with intravascular extension: a single-institution experience

The purpose of this study was to retrospectively analyze the clinical presentation, treatment, and outcomes of children with Wilms tumor (WT) and intravascular extension who were treated at a single institution. A retrospective review was conducted of medical records of all children with Wilms tumor and intravascular extension treated at Virgen del Rocio Children's Hospital between 1992 and 2010. Seven patients (median age 3.4 years, range 2-8.1 years) were identified. At diagnosis, 6 of the 7 patients (85.7%) presented with tumor thrombus that reached the right atrium (RA) and 1 patient with infrahepatic inferior vena cava (IVC) thrombus. All patients received neoadjuvant chemotherapy (SIOP 2001 protocol) with vincristine, doxorubicin, and actinomycin D. Regression of the intravascular extension of the tumor was documented in all patients. Postchemotherapy level of extension was suprahepatic IVC in 1 patient, infrahepatic IVC in 2 patients, renal vein (RV) in 1 patient, and RA in 3 patients. Nephrectomy and thrombectomy were performed in all cases, requiring cardiopulmonary bypass for the 4 patients who presented with suprahepatic IVC and RA thrombus. The other 3 patients with infrahepatic IVC and RV involvement underwent cavotomy and thrombus extraction. Computed tomography, ultrasonography, and echocardiography were used for diagnosis and follow-up. All patients remain disease-free with a median follow-up of 6.3 years (range, 2-19 years). Neoadjuvant chemotherapy for WT with intravascular extension may facilitate the resection by decreasing the extent of the tumor thrombus. Cardiopulmonary bypass is indicated for suprahepatic IVC and RA involvement. Accurate diagnostic imaging is necessary.