Molecular and descriptive epidemiologyof multidrug-resistant Enterobacteriaceae in hospitalized infants.

OBJECTIVE: To investigate the epidemiology of multidrug-resistant Enterobacteriaceae (MDRE) in hospitalized infants. METHODS: From 2000 through 2005, active surveillance cultures for MDRE were performed for patients admitted to a 40-bed neonatal intensive care unit (NICU) that provides care for critically ill infants 6 months of age or younger. MDRE epidemiology and the genetic relatedness of MDRE strains determined by repetitive-sequence polymerase chain reaction were analyzed. RESULTS: Active surveillance cultures revealed that 759 (23%) of 3,370 NICU infants (or approximately 1 in 5) developed MDRE colonization or infection and that 613 (72%) of the 853 isolates with epidemiologic data available were healthcare acquired. MDRE colonization occurred more frequently (in 653 infants [86%]) than did MDRE infection (in 106 [14%]). Of the 653 infants with MDRE colonization, 119 (18%) eventually became infected, with 29 (4%) acquiring sterile site infections. The most commonly isolated organisms were the Enterobacter species, accounting for 612 (71%) of the 862 isolates. Molecular epidemiologic analysis revealed that genetic-relatedness clustering (related clusters defined as having a genetic similarity coefficient greater than 95%) varied depending on microbial species. Clustering was detected for 36 (78%) of the 46 Enterobacter aerogenes isolates, 22 (45%) of the 49 Enterobacter cloacae isolates, and 13 (59%) of the 22 Klebsiella pneumoniae isolates. CONCLUSION: Hospitalized infants are at significant risk of acquiring MDRE, specifically Enterobacter species, at the study institution. Active surveillance cultures identified colonized patients who likely contributed to the institutional reservoir of MDRE. Molecular epidemiologic studies suggest that both patient-to-patient transmission and de novo acquisition of resistance play a role in the acquisition of these organisms, and that the clinical significance of such acquisition varies by species. The high percentage of E. aerogenes isolates that demonstrated genetic clustering suggests that monitoring the prevalence of this organism could serve as a useful measure of compliance with infection control procedures.     

Anatomy of a proficient enzyme: the structure of orotidine 5'-monophosphate decarboxylase in the presence and absence of a potential transition state analog

Orotidine 5'-phosphate decarboxylase produces the largest rate enhancement that has been reported for any enzyme. The crystal structure of the recombinant Saccharomyces cerevisiae enzyme has been determined in the absence and presence of the proposed transition state analog 6-hydroxyuridine 5'-phosphate, at a resolution of 2.1 A and 2.4 A, respectively. Orotidine 5'-phosphate decarboxylase folds as a TIM-barrel with the ligand binding site near the open end of the barrel. The binding of 6-hydroxyuridine 5'-phosphate is accompanied by protein loop movements that envelop the ligand almost completely, forming numerous favorable interactions with the phosphoryl group, the ribofuranosyl group, and the pyrimidine ring. Lysine-93 appears to be anchored in such a way as to optimize electrostatic interactions with developing negative charge at C-6 of the pyrimidine ring, and to donate the proton that replaces the carboxylate group at C-6 of the product. In addition, H-bonds from the active site to O-2 and O-4 help to delocalize negative charge in the transition state. Interactions between the enzyme and the phosphoribosyl group anchor the pyrimidine within the active site, helping to explain the phosphoribosyl group's remarkably large contribution to catalysis despite its distance from the site of decarboxylation.     

A wish-list for improving Australian women's reproductive health in the new millennium

Australian women are missing out in terms of their reproductive health, when compared to women in other developed countries. Now seems an appropriate moment in time to spell out the nature of their disadvantages, and suggest ways in which they could be overcome.     

Morbid hypocalcemia associated with phosphate enema in a six-week-old infant

A 6-week-old premature infant who was born at 29 weeks of gestation presented to the emergency department with a several-hour history of stiffness and increased alarms on his apnea monitor at home. On arrival he was noted to have generalized seizures, apnea, and bradycardia. He was intubated and required cardiopulmonary resuscitation including chest compressions and medications. After stabilization he was transferred to the neonatal intensive care unit for further management. His initial laboratory tests revealed a serum calcium level of 2.4 mg/dL (normal range: 8.4-10.2 mg/dL) and a serum phosphorus level of 28.5 mg/dL (normal range: 2.4-4.5 mg/dL). During the first week of admission, the infant's mother reported that she had administered a full pediatric Fleets enema (CB Fleet Company Inc, Lynchburg, VA) to him. The infant was discharged after 12 days of hospitalization. Anticipatory guidance on the stool patterns and behavior of infants can prevent misconceptions about constipation that are especially prevalent in new parents. Proper management of constipation, should it arise, should be addressed with all parents at early well-child visits to avoid hazardous complications of treatments. hypocalcemia, seizures, premature infants, enema.     

染色红花中酸性橙Ⅱ测定法的研究

目的:建立红花中酸性橙Ⅱ的高效液相色谱定量测定方法,了解市售中药饮片红花中酸性橙Ⅱ的污染情况。方法:HPLC 法,Diamonsil~(TM) C_(18)色谱柱(250 mm ×4.6 mm,5μm),流动相为0.025 mol·L~(-1)磷酸二氢钾溶液(含0.2%三乙胺,用磷酸调节 pH 值为3.0):乙腈(55:45),检测波长为484 nm,流速为1.0 mL·min~(-1),柱温为35℃,进样量为10μL。结果:酸性橙Ⅱ的浓度在0.000299～0.074790 mg·mL~(-1)范围内与其峰面积的线性关系良好(r=0.9999),平均加样回收率为100.1%(RSD=0.28%)。市售的31批红花中酸性橙Ⅱ的检出率为48%,检出量为6～329 mg·(100 g)~(-1)。结论:本法简便、快速、准确。可用于染色红花中酸性橙Ⅱ的测定。市售红花染色现象严重。     

Gender and age differences in plasma carnitine, muscle strength, and exercise tolerance in haemodialysis patients.

BACKGROUND: Haemodialysis patients have impaired exercise tolerance that may be related to impaired carnitine availability and/or alterations in carnitine metabolism. As carnitine metabolism is sex- and age-related, we examined plasma free and esterified carnitine concentrations, muscle strength, and estimated exercise tolerance in female (n=51) and male (n=63) patients of different ages (18-86 years). METHODS: Concentrations of free carnitine and acetylcarnitine were determined in the plasma of patients. Isometric handgrip strength was measured using a dynamometer while exercise tolerance was predicted from scores for self-reported walking distance on the level and on an incline. RESULTS: Plasma total carnitine concentration in the females was significantly lower than that of males (35.4+/-1.3 and 42.4+/-1.4 micro mol/l, respectively, P<0.01). This was almost entirely due to the lower plasma free carnitine concentration of females when compared with the males (20.6+/-0.9 and 26.3+/-1.1 micro mol/l, respectively, P<0.05). Furthermore, plasma free carnitine concentrations were negatively correlated with age in females (r=-0.45, P<0.001) even when the linear effects of haemoglobin, albumin, body weight, time on dialysis, and muscle strength were removed from the regression analysis (partial correlation coefficient; pcc=-0.43, P=0.018), but not in the males (r=0.03, P>0.05). Isometric handgrip strength and estimated exercise tolerance on the level were lower in females than males (138.9+/-10.9 and 259.0+/-15.2 N, P<0.001; and 3.5+/-0.2 and 4.3+/-0.2, P<0.05, respectively). Isometric handgrip strength and estimated exercise tolerance (walking distance on the level and on an incline) were positively correlated with plasma free carnitine concentrations in females, but not in the males. CONCLUSIONS: There was a strong relationship between plasma free carnitine concentrations and age in female patients, but not in males. It is unlikely that the reduction in plasma free carnitine in females was a direct causative factor in their reduced exercise tolerance, but probably reflects greater muscle de-conditioning/atrophy with age in female patients.     

The Acute Care Undergraduate TEaching (ACUTE) Initiative: consensus development of core competencies in acute care for undergraduates in the United Kingdom

Background The care of the acutely ill patient in hospital is often sub-optimal. Poor recognition of critical illness combined with a lack of knowledge, failure to appreciate the clinical urgency of a situation, a lack of supervision, failure to seek advice and poor communication have been identified as contributory factors. At present the training of medical students in these important skills is fragmented. The aim of this study was to use consensus techniques to identify the core competencies in the care of acutely ill or arrested adult patients that medical students should possess at the point of graduation.Design Healthcare professionals were invited to contribute suggestions for competencies to a website as part of a modified Delphi survey. The competency proposals were grouped into themes and rated by a nominal group comprised of physicians, nurses and students from the UK. The nominal group rated the importance of each competency using a 5-point Likert scale.Results A total of 359 healthcare professionals contributed 2,629 competency suggestions during the Delphi survey. These were reduced to 88 representative themes covering: airway and oxygenation; breathing and ventilation; circulation; confusion and coma; drugs, therapeutics and protocols; clinical examination; monitoring and investigations; team-working, organisation and communication; patient and societal needs; trauma; equipment; pre-hospital care; infection and inflammation. The nominal group identified 71 essential and 16 optional competencies which students should possess at the point of graduation.Conclusions We propose these competencies form a core set for undergraduate training in resuscitation and acute care.Electronic Supplementary Material Electronic supplementary material to this paper can be obtained by using the Springer Link server located at This study was supported by an unrestricted research grant from the Resuscitation Council (UK). The funding organisation hosted the website for phase 1 of the study and provided accommodation and travel costs for the nominal group meeting. The funding organisation did not contribute to the study design, analysis or interpretation of results or decision to submit for publication.     

Carotid artery intimal medial thickness, brachial artery flow-mediated vasodilation and cardiovascular risk factors in diabetic and non-diabetic indigenous Australians

BACKGROUND: Indigenous Australians are at high risk for cardiovascular disease and type 2 diabetes. Carotid artery intimal medial thickness (CIMT) and brachial artery flow-mediated vasodilation (FMD) are ultrasound imaging based surrogate markers of cardiovascular risk. This study examines the relative contributions of traditional cardiovascular risk factors on CIMT and FMD in adult Indigenous Australians with and without type 2 diabetes mellitus. METHOD: One hundred and nineteen Indigenous Australians were recruited. Physical and biochemical markers of cardiovascular risk, together with CIMT and FMD were measured for all subjects. RESULTS: Fifty-three Indigenous Australians subjects (45%) had type 2 diabetes mellitus. There was a significantly greater mean CIMT in diabetic versus non-diabetic subjects (p=0.049). In the non-diabetic group with non-parametric analyses, there were significant correlations between CIMT and: age (r=0.64, p<0.001), systolic blood pressure (r=0.47, p<0.001) and non-smokers (r=-0.30, p=0.018). In the diabetic group, non-parametric analysis showed correlations between CIMT, age (r=0.36, p=0.009) and duration of diabetes (r=0.30, p=0.035) only. Adjusting for age, sex, smoking and history of cardiovascular disease, Hb(A1c) became the sole significant correlate of CIMT (r=0.35, p=0.01) in the diabetic group. In non-parametric analysis, age was the sole significant correlate of FMD (r=-0.31, p=0.013), and only in non-diabetic subjects. Linear regression analysis showed significant associations between CIMT and age (t=4.6, p<0.001), systolic blood pressure (t=2.6, p=0.010) and Hb(A1c) (t=2.6, p=0.012), smoking (t=2.1, p=0.04) and fasting LDL-cholesterol (t=2.1, p=0.04). There were no significant associations between FMD and examined cardiovascular risk factors with linear regression analysis CONCLUSIONS: CIMT appears to be a useful surrogate marker of cardiovascular risk in this sample of Indigenous Australian subjects, correlating better than FMD with established cardiovascular risk factors. A lifestyle intervention programme may alleviate the burden of cardiovascular disease in Indigenous Australians by reducing central obesity, lowering blood pressure, correcting dyslipidaemia and improving glycaemic control. CIMT may prove to be a useful tool to assess efficacy of such an intervention programme.     

Clinical use of new-generation pulse oximeters in the neonatal intensive care unit

Continuous monitoring by pulse oximetry is a common practice for preterm and critically ill newborns. A new generation of motion-tolerant pulse oximeters have been designed for improved clinical performance with a substantial reduction in alarm frequency. However, little is known about the differences among these new-generation pulse oximeters in the neonatal intensive care unit (NICU). The purpose of this study is to assess the clinical performance of two new-generation pulse oximeters in the NICU. Two new-generation pulse oximeters were used simultaneously to monitor 36 patients in the NICU. The two devices studied were the Philips FAST and the Masimo SET. Patients were randomly assigned for their digit selection and data were collected only when waveforms were of good quality and/or the pulse oximeter's pulse rate (PR) correlated with the electrocardiogram heart rate (HR). The data for oxygen saturation measurements, number of true and false alarms, and number of dropouts as well as the duration of dropouts for each pulse oximeter were recorded by the primary investigator at 5-minute intervals for a period of 2 hours on each patient. Dropouts are instances when the pulse oximeter alarm sounds due to its inability to identify the arterial pulse and provide an oxygen saturation reading. The mean gestational age for the study group was 32 weeks (rang, 24 to 42 weeks). Repeated-measures analysis of variance indicated no difference between the two devices across all time measurements (p=0.357). In addition, paired t-tests for true alarms and false alarms were not significant, with p-values of 0.151 and 0.869, respectively. There was a difference in the number of data dropouts (p<0.001): the Philips device had a nearly six-fold increase in the number of dropouts (Philips 247 versus Masimo 38). The duration of dropouts was also significant; the Philips device had three times longer duration of dropouts. Physiologic monitoring in the critical care setting requires accurate data measurements. The two new-generation pulse oximeters, the Philips FAST and Masimo SET, are equally sensitive in their ability to identify true and false alarms. Masimo pulse oximeter with its signal extraction technology, however, provides more consistent and accurate reporting of SpO2 values as demonstrated by its markedly decreased incidence of data dropouts. The Masimo unit appears to be more resistant to the effects of motion artifact.