Isolation and primary cultures of human intrahepatic bile ductular epithelium

A technique for the isolation of human intrahepatic bile ductular epithelium, and the establishment of primary cultures using a serum- and growth-factor-supplemented medium combined with a connective tissue substrata is described. Initial cell isolates and monolayer cultures display phenotypic characteristics of biliary epithelial cells (low molecular weight prekeratin positive; albumin, alphafetoprotein, and Factor VIII-related antigen negative). Ultrastructural features of the cultured cells show cell polarization with surface microvilli, numerous interepithelial junctional complexes and cytoplasmic intermediate prekeratin filaments. © 1988 Tissue Culture Association, Inc

Measuring and modelling towline responses using GPS aided inertial navigation

The offshore towage of large floating structures has been the broad subject of research since the 1960’s. The selection of a tug to engage in a tow is based on rules laid down by class and marine warranty surveyors derived from years of experience but a rigorous assessment of these rules based on a comprehensive real world datasets has not been possible. This is principally due to the nature of these tows, usually employing tugs chartered at short notice from the spot market, the long towline lengths when under tow and the high value of the tow itself. Given the commercial implications in being able to better match a suitable tug to any given tow, this research lays down the requirements of an ideal dataset, i.e. one that has a record of towline tensions, complete 6DOF of both the tug and tow all recorded to a universal timeline, along with the seastate experienced by the tow at any given point. It then reviews the historical restrictions in gathering this data and that the key issue has been gathering the motions of the unpowered tow and recording the towline tensions.A methodology is then developed which requires no interference with the towline and draws upon Kalman filters for optimal state estimation of the tug and tow’s position and attitude in 3D space driving a lumped mass simulation of the towline coded in MatLab. The stiffness properties of key elements of the towline are assessed by FEA and observations made on areas where normal industry practice’s may be lacking. Observations on advances in sensor technology as well as other areas for development are then made that provide fertile areas for further research. Finally the full code base for a MatLab, lumped mass simulator is presented in an appendix for future use.The offshore towage of large floating structures has been the broad subject of research since the 1960’s. The selection of a tug to engage in a tow is based on rules laid down by class and marine warranty surveyors derived from years of experience but a rigorous assessment of these rules based on a comprehensive real world datasets has not been possible. This is principally due to the nature of these tows, usually employing tugs chartered at short notice from the spot market, the long towline lengths when under tow and the high value of the tow itself. Given the commercial implications in being able to better match a suitable tug to any given tow, this research lays down the requirements of an ideal dataset, i.e. one that has a record of towline tensions, complete 6DOF of both the tug and tow all recorded to a universal timeline, along with the seastate experienced by the tow at any given point. It then reviews the historical restrictions in gathering this data and that the key issue has been gathering the motions of the unpowered tow and recording the towline tensions.A methodology is then developed which requires no interference with the towline and draws upon Kalman filters for optimal state estimation of the tug and tow’s position and attitude in 3D space driving a lumped mass simulation of the towline coded in MatLab. The stiffness properties of key elements of the towline are assessed by FEA and observations made on areas where normal industry practice’s may be lacking. Observations on advances in sensor technology as well as other areas for development are then made that provide fertile areas for further research. Finally the full code base for a MatLab, lumped mass simulator is presented in an appendix for future use

Methylated DNA recognition during the reversal of epigenetic silencing is regulated by cysteine and cerine residues in the Epstein-Barr Virus lytic switch protein

Epstein-Barr virus (EBV) causes infectious mononucleosis and is associated with various malignancies, including Burkitt's lymphoma and nasopharyngeal carcinoma. Like all herpesviruses, the EBV life cycle alternates between latency and lytic replication. During latency, the viral genome is largely silenced by host-driven methylation of CpG motifs and, in the switch to the lytic cycle, this epigenetic silencing is overturned. A key event is the activation of the viral BRLF1 gene by the immediate-early protein Zta. Zta is a bZIP transcription factor that preferentially binds to specific response elements (ZREs) in the BRLF1 promoter (Rp) when these elements are methylated. Zta's ability to trigger lytic cycle activation is severely compromised when a cysteine residue in its bZIP domain is mutated to serine (C189S), but the molecular basis for this effect is unknown. Here we show that the C189S mutant is defective for activating Rp in a Burkitt's lymphoma cell line. The mutant is compromised both in vitro and in vivo for binding two methylated ZREs in Rp (ZRE2 and ZRE3), although the effect is striking only for ZRE3. Molecular modeling of Zta bound to methylated ZRE3, together with biochemical data, indicate that C189 directly contacts one of the two methyl cytosines within a specific CpG motif. The motif's second methyl cytosine (on the complementary DNA strand) is predicted to contact S186, a residue known to regulate methyl-ZRE recognition. Our results suggest that C189 regulates the enhanced interaction of Zta with methylated DNA in overturning the epigenetic control of viral latency. As C189 is conserved in many bZIP proteins, the selectivity of Zta for methylated DNA may be a paradigm for a more general phenomenon

Between feminism and anorexia: An autoethnography

Critical feminist work on eating disorders has grown substantially since its establishment in the 1980s, and has increasingly incorporated the use of anorexic stories, voices and experiences. Yet rarely do such accounts offer the anorexic a space to respond to the now established feminist conceptions of the problem which structure the books or articles in which they appear. Anorexic, or recovered anorexic, voices are used by the researcher to interpret the role played by gender, even whilst the subjects are invited to respond to and critique, medical and popular discourses on the disorder. This lack of dialogue is all the more striking in the context of the feminist aim to fight ‘back against the tendency to silence anorexic women’s’ own interpretations of their starving, treatment and construction (Saukko, 2008: 34). As someone who suffered from anorexia for 20 years, this article offers an autoethnographic account of my experience of encountering the feminist literature on anorexia in a bid to speak back, or enter into a dialogue between feminist politics and eating disorder experience

The Response of the Nucleus Pulposus of the Lumbar Intervertebral Discs to Functionally Loaded Positions

Study design: Asymptomatic volunteers underwent magnetic resonance imaging to investigate how different positions affect lumbar intervertebral discs. Objective: To quantify sagittal migration of the lumbar nucleus pulposus in 6 functional positions. Summary of background data: Previous studies of the intervertebral disc response in the sagittal plane were limited to imaging of recumbent positions. Developments of upright magnetic resonance imaging permit investigation of functional weight-bearing positions. Methods: T2-weighted sagittal scans of the L1-L2 to L5-S1 discs were taken of 11 volunteers in standing, sitting (upright, flexed, and in extension), supine, and prone extension. Sagittal migration of the nucleus pulposus was measured (mm) as distance from anterior disc boundary to peak pixel intensity. Lumbar lordosis (Cobb angle) was measured in each position. Results: Fifteen comparisons between positions showed significant positional effects (14 at L4-L5, L5-S1, the most mobile segments). Prone extension and supine lying induced significantly less posterior migration than sitting. Flexed and upright sitting, significantly more than standing at L4-L5, as did flexed sitting compared with extended. Conclusion: These results support for the first time the validity of clinical assumptions about disc behavior in functional positions: sitting postures may increase risk of posterior derangement, and prone and supine may be therapeutic for symptoms caused by posterior disc displacement

A retrospective review and multi-specialty, evidence-based guideline for the management of necrotising otitis externa

BACKGROUND: Necrotising otitis externa is a progressive infection of the external auditory canal which extends to affect the temporal bone and adjacent structures. Progression of the disease process can result in serious sequelae, including cranial nerve palsies and death. There is currently no formal published treatment guideline.OBJECTIVE: This study aimed to integrate current evidence and data from our own retrospective case series in order to develop a guideline to optimise necrotising otitis externa patient management.METHODS: A retrospective review of necrotising otitis externa cases within NHS Lothian, Scotland, between 2013 and 2018, was performed, along with a PubMed review.RESULTS: Prevalent presenting signs, symptoms and patient demographic data were established. Furthermore, features of cases associated with adverse outcomes were defined. A key feature of the guideline is defining at-risk patients with initial intensive treatment. Investigations and outcomes are assessed and treatment adjusted appropriately.CONCLUSION: This multi-departmental approach has facilitated the development of a succinct, systematic guideline for the management of necrotising otitis externa. Initial patient outcomes appear promising.</p