Development of an efficient, scalable, aldolase-catalyzed process for enantioselective synthesis of statin intermediates

A process is reported for efficient, enantioselective production of key intermediates for the common chiral side chain of statin-type cholesterol-lowering drugs such as Lipitor (atorvastatin) and Crestor (rosuvastatin). The process features a one-pot tandem aldol reaction catalyzed by a deoxyribose-5-phosphate aldolase (DERA) to form a 6-carbon intermediate with installation of two stereogenic centers from 2-carbon starting materials. An improvement of almost 400-fold in volumetric productivity relative to the published enzymatic reaction conditions has been achieved, resulting in a commercially attractive process that has been run on up to a 100-g scale in a single batch at a rate of 30.6 g/liter per h. Catalyst load has been improved by 10-fold as well, from 20 to 2.0 wt % DERA. These improvements were achieved by a combination of discovery from environmental DNA of DERAs with improved activity and reaction optimization to overcome substrate inhibition. The two stereogenic centers are set by DERA with enantiomeric excess at >99.9% and diastereomeric excess at 96.6%. In addition, down-stream chemical steps have been developed to convert the enzymatic product efficiently to versatile intermediates applicable to preparation of atorvastatin and rosuvastatin.     

Use of arterial transfer functions for the derivation of aortic waveform characteristics

OBJECTIVE: To investigate the utility and accuracy of radial-aortic arterial transfer functions for the derivation of central blood pressure waveforms.DESIGN Prospective measurement of central and peripheral waveforms in patients undergoing coronary angiography or percutaneous coronary intervention. METHODS: Simultaneous invasive central aortic and non-invasive radial pressure waveforms were recorded in 78 subjects (61 male : 17 female). Data were applied to a single-input/single-output model for the calculation of a transfer function (TF). Individual TFs were derived by two methods and ensemble averaged TFs obtained for the group. Reverse transformation was performed using each averaged TF applied to the radial data of each subject. RESULTS: There was close linear correlation between measured aortic parameters and both radial and TF-derived aortic systolic and diastolic pressures (P < 0.001) and most other waveform parameters. However, despite small mean differences between measured and most TF-derived aortic parameters (systolic pressure 0.8-2.9 mmHg, augmentation index 4.3-5.6%), individual scatter was marked, with 95% limits of agreement of +/- 14.6 mmHg (systolic pressure) and +/- 24.4% [augmentation index (AI)]. Indeed, scatter for AI was so marked that measured and derived values were not statistically significantly correlated. CONCLUSIONS: Transfer functions may be valid for the derivation of some central aortic waveform characteristics. However, in providing neither improved reproducibility nor data on parameters not obtainable from the radial waveform, transfer function techniques may offer no additional clinical benefit. The absence of correlation between measured and TF-derived aortic AI and wide limits of agreement of other parameters should be considered if this technique is utilized in clinical practice.     

A multicenter study of total pancreatectomy with islet autotransplantation (TPIAT): POST (Prospective Observational Study of TPIAT)

Background/objectives

Total pancreatectomy with islet autotransplantation (TPIAT) is considered for managing chronic pancreatitis in selected patients when medical and endoscopic interventions have not provided adequate relief from debilitating pain. Although more centers are performing TPIAT, we lack large, multi-center studies to guide decisions about selecting candidates for and timing of TPIAT.

KSR stimulates Raf-1 activity in a kinase-independent manner

Kinase suppressor of Ras (KSR) is an evolutionarily conserved component of Ras-dependent signaling pathways. Here, we find that murine KSR (mKSR1) translocates from the cytoplasm to the plasma membrane in the presence of activated Ras. At the membrane, mKSR1 modulates Ras signaling by enhancing Raf-1 activity in a kinase-independent manner. The activation of Raf-1 is mediated by the mKSR1 cysteine-rich CA3 domain and involves a detergent labile cofactor that is not ceramide. These findings reveal another point of regulation for Ras-mediated signal transduction and further define a noncatalytic role for mKSR1 in the multistep process of Raf-1 activation.     

Endosonographic Imaging of Anal Sphincter Injury

PURPOSE: This study was designed to test the hypothesis that the extent of anal sphincter muscle injury as graded at endosonography correlates with the degree of functional impairment. METHODS: Three hundred and thirty adults presenting for evaluation of fecal incontinence were recruited. Ultrasound was performed with a 7.5-MHz radial rotating axial endoprobe in the left lateral position. Anal sphincter muscle tears were graded on the basis of the degree of circumferential involvement (< or >25 percent) and by an assessment of the superoinferior longitudinal extent of an external anal sphincter tear. Muscles that demonstrated multiple tears, poor visualization, or fragmentation were classed as fragmented. Sphincter injuries were correlated with basal and squeeze pressures at manometry, pudendal nerve terminal latencies, and the severity of symptoms using the Parks-Browning clinical score. RESULTS: Patients with an intact external anal sphincter had a higher squeeze pressure (mean, 162.6 cm H(2)O) than those with a partial- (mean, 125.7 cm H(2)O) or full-length tear (mean, 124.9 cm H(2)O; P < 0.0001). There was no significant difference in squeeze pressure between those with partial- vs. full-length external anal sphincter tears nor between circumference tears < or >25 percent. Basal pressure was significantly lower in those with a full-length external anal sphincter tear (47.8 cm H(2)O) vs. an intact external anal sphincter (65.7 cm H(2)O; P < 0.001). The basal pressure in those with an intact internal anal sphincter was not significantly different from those with clearly defined internal anal sphincter tears, and the degree of circumferential involvement was also not important in this regard. However, those with a fragmented internal anal sphincter had a significantly lower basal pressure than other subgroups of internal anal sphincter injuries (P < 0.001). There was no association between external or internal anal sphincter status and the mean pudendal nerve terminal motor latency, suggesting the patient groups were neurologically similar. There was no significant association between external or internal anal sphincter status and the severity of reported symptoms. CONCLUSION: Correlations between the presence or absence of muscle tears and reduced manometric function have been identified. Further grading of tears was of less importance. No relationship between muscle injuries and the severity of clinical symptoms could be elicited.     

Corticotropin-releasing factor-1 receptor involvement in behavioral neuroadaptation to ethanol: a urocortin1-independent mechanism

A common expression of neuroadaptations induced by repeated exposure to addictive drugs is a persistent sensitized behavioral response to their stimulant properties. Neuroplasticity underlying drug-induced sensitization has been proposed to explain compulsive drug pursuit and consumption characteristic of addiction. The hypothalamic-pituitary-adrenal (HPA) axis-activating neuropeptide, corticotropin-releasing factor (CRF), may be the keystone in drug-induced neuroadaptation. Corticosterone-activated glucocorticoid receptors (GRs) mediate the development of sensitization to ethanol (EtOH), implicating the HPA axis in this process. EtOH-induced increases in corticosterone require CRF activation of CRF1 receptors. We posited that CRF1 signaling pathways are crucial for EtOH-induced sensitization. We demonstrate that mice lacking CRF1 receptors do not show psychomotor sensitization to EtOH, a phenomenon that was also absent in CRF1 + 2 receptor double-knockout mice. Deletion of CRF2 receptors alone did not prevent sensitization. A blunted endocrine response to EtOH was found only in the genotypes showing no sensitization. The CRF1 receptor antagonist CP-154,526 attenuated the acquisition and prevented the expression of EtOH-induced psychomotor sensitization. Because CRF1 receptors are also activated by urocortin-1 (Ucn1), we tested Ucn1 knockout mice for EtOH sensitization and found normal sensitization in this genotype. Finally, we show that the GR antagonist mifepristone does not block the expression of EtOH sensitization. CRF and CRF1 receptors, therefore, are involved in the neurobiological adaptations that underlie the development and expression of psychomotor sensitization to EtOH. A CRF/CRF1-mediated mechanism involving the HPA axis is proposed for acquisition, whereas an extrahypothalamic CRF/CRF1 participation is suggested for expression of sensitization to EtOH.     

Development and Early Implementation of The Bigger Picture,a Youth-Targeted Public Health Literacy Campaign to Prevent Type 2 Diabetes

The prevalence of type 2 diabetes is rapidly rising, especially among minority and low-income youth. There is an unmet need to engage youth in identifying solutions to reverse this trajectory. Social marketing campaigns and entertainment education are effective forms of health communication for engaging populations in health-promoting behaviors. Critical to curbing the epidemic is moving the diabetes conversation away from individual behavior alone and toward a socioecologic perspective using a public health literacy framework. The authors developed an academic-community partnership to develop, implement, and evaluate a type 2 diabetes prevention campaign targeting minority and low-income youth. The Bigger Picture campaign uses hard-hitting, youth-generated spoken-word messages around key environmental and social drivers of the type 2 diabetes epidemic. Campaign goals included promoting health capacity and civic engagement. This article focuses on the development and implementation of the campaign, including (a) rationale and theoretical underpinnings, (b) steps in campaign creation, (c) testing the campaign messaging, and (d) campaign dissemination and evaluation planning. A youth-created health communication campaign using a public health literacy framework with targeted, relevant, and compelling messaging appears to be a promising vehicle for reaching at-risk youth to increase knowledge of and attitudes about preventing type 2 diabetes, change social norms, and motivate participation in health-promoting initiatives.     

Breastfeeding Practices in Relation to Country of Origin Among Women Living in Denmark: A Population-Based Study

The objective of this study was to describe breastfeeding practices and to compare the risk of suboptimal breastfeeding of women living in Denmark according to country of origin, and further to examine how socio-economic position and duration of stay in the country affected this risk. Information on breastfeeding of 42,420 infants born 2002–2009 and living in eighteen selected Danish municipalities was collected from the Danish Health Visitor’s Child Health Database. The data was linked with data on maternal socio-demographic information from Danish population-covering registries. Suboptimal breastfeeding was defined as <4 months of full breastfeeding as described by the Danish Health and Medicines Authority. We used logistic regression to model the crude associations between suboptimal breastfeeding and country of origin, and taking maternal age and parity, and a variety of parental socio-economic measures into account. Suboptimal breastfeeding was more frequent among non-Western migrant women than among women of Danish origin. Women who were descendants of Turkish and Pakistani immigrants had a higher risk of suboptimal breastfeeding as compared to the group of women who had migrated from the same countries, suggesting that acculturation did not favor breastfeeding. For all but the group of women who had migrated from Pakistan, adjustment for socio-demographic indicators (age, parity, education, attachment to labour market, and income) eliminated the increased risk of suboptimal breastfeeding. There was no evidence for differences in the breastfeeding support provided at hospital level according to migrant status. Suboptimal breastfeeding was more frequent among women who were non-Nordic migrants and descendants of migrants than among women with Danish origin.     

‘I could never have learned this in a lecture’: transformative learning in rural health education

Health indicators for rural populations in Australia continue to lag behind those of urban populations and particularly for Indigenous populations who make up a large proportion of people living in rural and remote Australia. Preparation of health practitioners who are adequately prepared to face the ‘messy swamps’ of rural health practice is a growing challenge. This paper examines the process of learning among health science students from several health disciplines from five Western Australian universities during ‘Country Week’: a one-week intensive experiential interprofessional education program in rural Western Australia. The paper weaves together strands of transformative theory of learning with findings from staff and student reflections from Country Week to explore how facilitated learning in situ can work to produce practitioners better prepared for rural health practice.