Retinoid absorption and storage is impaired in mice lacking lecithin:retinol acyltransferase (LRAT)

Journal ArticleLecithin:retinol acyltransferase (LRAT) is believed to be the predominant if not the sole enzyme in the body responsible for the physiologic esterification of retinol. We have studied Lrat-deficient (Lrat-/-) mice to gain a better understanding of how these mice take up and store dietary retinoids and to determine whether other enzymes may be responsible for retinol esterification in the body. Although the Lrat-/- mice possess only trace amounts of retinyl esters in liver, lung, and kidney, they possess elevated (by 2-3-fold) concentrations of retinyl esters in adipose tissue compared with wild type mice. These adipose retinyl ester depots are mobilized in times of dietary retinoid insufficiency. We further observed an up-regulation (3-4-fold) in the level of cytosolic retinol-binding protein type III (CRBPIII) in adipose tissue of Lrat-/- mice. Examination by electron microscopy reveals a striking total absence of large lipid-containing droplets that normally store hepatic retinoid within the hepatic stellate cells of Lrat-/- mice. Despite the absence of significant retinyl ester stores and stellate cell lipid droplets, the livers of Lrat-/- mice upon histologic analysis appear normal and show no histological signs of liver fibrosis. Lrat-/- mice absorb dietary retinol primarily as free retinol in chylomicrons; however, retinyl esters are also present within the chylomicron fraction obtained from Lrat-/- mice. The fatty acyl composition of these (chylomicron) retinyl esters suggests that they are synthesized via an acyl-CoA-dependent process suggesting the existence of a physiologically significant acyl-CoA:retinol acyltransferase

Examining 'window dressing' : the views of black police associations on recruitment and training

In a previous issue of this journal, Ellis Cashmore (2002 Cashmore, E. 2002. ‘Behind the window dressing: minority ethnic police perspectives on cultural diversity’. Journal of Ethnic and Migration Studies, 28(2): 327–41. [Taylor & Francis Online], [CSA], [Google Scholar] ) discussed two key issues currently confronting police constabularies in England and Wales: the recruitment of minority ethnic officers and civilian staff, and the impact of diversity training now in place for all police officers. Cashmore argued that not only are these policies ineffective in enhancing cultural diversity within constabularies, but that they are harmful, presenting a false outward image of effective action. This article examines Cashmore's arguments and develops them in light of findings from recent research on Black Police Associations (BPAs) in England and Wales. Our findings firstly suggest that, because of heavy involvement with these initiatives and the close relationship BPAs have developed with senior management (in comparison to non-BPA members), they must be considered in any discussion of minority ethnic recruitment and diversity training. In addition, the majority of the officers we interviewed were supportive of current recruitment and training programmes. Secondly, we argue that BPAs are helping to change the nature of the overall police culture to a certain extent. Many minority ethnic officers no longer feel they must downplay their ethnicity as members of constabularies

Effect of vibration on the shear strength of impacted bone graft in revision hip surgery

Aims: Studies on soil mechanics have established that when vibration is applied to an aggregate, it results in more efficient alignment of particles and reduces the energy required to impact the aggregate. Our aim was to develop a method of applying vibration to the bone impaction process and assess its impact on the mechanical properties of the impacted graft. Methods: Phase 1. Eighty bovine femoral heads were milled using the Noviomagus bone mill. The graft was then washed using a pulsed lavage normal saline system over a sieve tower. A vibration impaction device was developed which housed two 15V DC motors with eccentric weights attached inside a metal cylinder. A weight was dropped onto this from a set height 72 times so as to replicate the bone impaction process. A range of frequencies of vibration were tested, as measured using an accelerometer housed in the vibration chamber. Each shear test was then repeated at four different normal loads so as to generate a family of stress-strain curves. The Mohr-Coulomb failure envelope from which the shear strength and interlocking values are derived was plotted for each test. Phase 2. Experiments were repeated with the addition of blood so as to replicate a saturated environment as is encountered during operative conditions. Results Phase 1. Graft impacted with the addition of vibration at all frequencies of vibration showed improved shear strength when compared to impaction without vibration. Vibration at sixty Hertz was displayed the largest effect and was found to be significant. 3 Phase 2. Graft impacted with the addition of vibration in a saturated aggregate displayed lower shear strengths for all normal compressive loads than that of impaction without vibration. Conclusions Civil engineering principles hold true for the impaction bone grafting procedure. In a dry aggregate the addition of vibration may be beneficial to the mechanical properties of the impacted graft. In our system the optimal frequency of vibration was 60 Hz. Under saturated conditions the addition of vibration is detrimental the shear strength of the aggregate. This may be explained by the process of liquefaction

Operative Outcomes for Cervical Myelopathy and Radiculopathy

Cervical spondylotic myelopathy and radiculopathy are common disorders which can lead to significant clinical morbidity. Conservative management, such as physical therapy, cervical immobilisation, or anti-inflammatory medications, is the preferred and often only required intervention. Surgical intervention is reserved for those patients who have intractable pain or progressive neurological symptoms. The goals of surgical treatment are decompression of the spinal cord and nerve roots and deformity prevention by maintaining or supplementing spinal stability and alleviating pain. Numerous surgical techniques exist to alleviate symptoms, which are achieved through anterior, posterior, or circumferential approaches. Under most circumstances, one approach will produce optimal results. It is important that the surgical plan is tailored to address each individual's unique clinical circumstance. The objective of this paper is to analyse the major surgical treatment options for cervical myelopathy and radiculopathy focusing on outcomes and complications

The radius and mass of the subgiant star bet Hyi from interferometry and asteroseismology

We have used the Sydney University Stellar Interferometer (SUSI) to measure the angular diameter of beta Hydri. This star is a nearby G2 subgiant whose mean density was recently measured with high precision using asteroseismology. We determine the radius and effective temperature of the star to be 1.814+/-0.017 R_sun (0.9%) and 5872+/-44 K (0.7%) respectively. By combining this value with the mean density, as estimated from asteroseismology, we make a direct estimate of the stellar mass. We find a value of 1.07+/-0.03 M_sun (2.8%), which agrees with published estimates based on fitting in the H-R diagram, but has much higher precision. These results place valuable constraints on theoretical models of beta Hyi and its oscillation frequencies.Comment: 3 figures, 3 tables, to appear in MNRAS Letter

The Use of Three-Dimensional DNA Fluorescent In Situ Hybridization (3D DNA FISH) for the Detection of Anaplastic Lymphoma Kinase (ALK) in Non-Small Cell Lung Cancer (NSCLC) Circulating Tumor Cells.

Tumor tissue biopsy is often limited for non-small cell lung cancer (NSCLC) patients and alternative sources of tumoral information are desirable to determine molecular alterations such as anaplastic lymphoma kinase (ALK) rearrangements. Circulating tumor cells (CTCs) are an appealing component of liquid biopsies, which can be sampled serially over the course of treatment. In this study, we enrolled a cohort of ALK-positive (n = 8) and ALK-negative (n = 12) NSCLC patients, enriched for CTCs using spiral microfluidic technology and performed DNA fluorescent in situ hybridization (FISH) for ALK. CTCs were identified in 12/20 NSCLC patients ranging from 1 to 26 CTCs/7.5 mL blood. Our study revealed that 3D imaging of CTCs for ALK translocations captured a well-defined separation of 3' and 5' signals indicative of ALK translocations and overlapping 3'/5' signal was easily resolved by imaging through the nuclear volume. This study provides proof-of-principle for the use of 3D DNA FISH in the determination of CTC ALK translocations in NSCLC