Study of human lymphoblastoid cell lines in tissue culture

The properties and potential applications of human lymphoblastoid cell linen have been investigated. Buch lines have been established by others from Burkitt's lymphoma tissue, from leukaetnic patients, from those with infectious mononucleosis and latterly from healthy subjects. There is an association between EB virus (Herpes-like virus of Epstein and Barr) and the growth of human lymphob1astold cell lines in vitro. The same virus is linked sero-epidemiologically with Burkitt's lymphoma, nasopharyngeal carcinoma, infectious mononucleosis and a number of other diseases of man. The exact role of the virus both in vivo and in vitro is a matter of some controversy. Using a simple culture technique, 40 cell lines were established from the peripheral blood leukocytes of a diaqnostically rai3:»d group of patients, from normal cord blood and from one h althy adult. 25 of these cultures were initiated by adding EB virus (in the form of lethally irradiated cells of a virus-positive line) to the fresh blood leukocytes. Evidence from experiments of this type suggest that EB virus has a lyraphoproliferative action in vitro. The cell lines are morphologically etlmost indistinguishable. They resemble primitive cells of the lymphoid series and appear to have the property of indefinite growth in vitro. They include some phagocytic cells and immunoglobulins are released into the culture medium. Feu of the lines were chromosomally abnormal when examined shortly after establishment but all of those examined after more than 1 year of continuous growth had abnormal karyotypes. There was no evidence for the recurrence of any specific chromosome aberration in a significant proportion of the lines. Antigenleally the established lines differ from the original donor's fresh lymphocytes. This is shown by measurement of tritiated thymidine uptake by lymphocytes exposed in vitro to irradiated cells from an autochthonous line. Together with the activation process, the fresh lymphocytes acquire cytotoxic potential directed specifically against the cell line used in the activation phase. Tt is suggested that this system constitutes a model for an immunological surveillance mechanism operating in vivo to eliminate deviant cells. Cell lines of this type offer rcone for detailed investiga¬ tion of the induction of proliferation in human tissue (in this case probably by FB virus) and of the immunological processes by which altered autochthonous cells may be recognised and destroyed. Both of these topics are relevant to the basic study of malignant disease. The prolonged life span and relative stability of these lines in vitro also presents opportunities in the Field of human genetics, both for the investigation of inherited disorders of man and, experimentally, for the measurement of spontaneous and induced mutation rates, analysis of gene linkage and chromosome mapping

Impact of nonlinear loss on Stimulated Brillouin Scattering

We study the impact of two-photon absorption (2PA) and fifth-order nonlinear loss such as 2PA-induced free-carrier absorption in semiconductors on the performance of Stimulated Brillouin Scattering devices. We formulate the equations of motion including effective loss coefficients, whose explicit expressions are provided for numerical evaluation in any waveguide geometry. We find that 2PA results in a monotonic, algebraic relationship between amplification, waveguide length and pump power, whereas fifth-order losses lead to a non-monotonic relationship. We define a figure of merit for materials and waveguide designs in the presence of fifth-order losses. From this, we determine the optimal waveguide length for the case of 2PA alone and upper bounds for the total Stokes amplification for the case of 2PA as well as fifth-order losses. The analysis is performed analytically using a small-signal approximation and is compared to numerical solutions of the full nonlinear modal equations

Power limits and a figure of merit for stimulated Brillouin scattering in the presence of third and fifth order loss

We derive a set of design guidelines and a figure of merit to aid the engineering process of on-chip waveguides for strong Stimulated Brillouin Scattering (SBS). To this end, we examine the impact of several types of loss on the total amplification of the Stokes wave that can be achieved via SBS. We account for linear loss and nonlinear loss of third order (two-photon absorption, 2PA) and fifth order, most notably 2PA-induced free carrier absorption (FCA). From this, we derive an upper bound for the output power of continuous-wave Brillouin-lasers and show that the optimal operating conditions and maximal realisable Stokes amplification of any given waveguide structure are determined by a dimensionless parameter $\mathcal{F}$ involving the SBS-gain and all loss parameters. We provide simple expressions for optimal pump power, waveguide length and realisable amplification and demonstrate their utility in two example systems. Notably, we find that 2PA-induced FCA is a serious limitation to SBS in silicon and germanium for wavelengths shorter than 2200nm and 3600nm, respectively. In contrast, three-photon absorption is of no practical significance

Investigating the thermosensitivity of cancer cell division dynamics:Toward cancer thermotherapies?

The application of heat to treat disease can be dated back over 5000 years. Ancient Egyptian papyrus records describe heated instruments being used to cauterise breast tumours. In recent times, hyperthermia range temperatures are increasingly routinely used to treat cancer. Heating tumours alongside conventional therapies and pre-heating aqueous drug suspensions prior to administration are both commonplace in oncology clinics. Despite this, the mechanisms which underpin the efficacy of hyperthermia therapy in cancer treatment remain poorly understood. In particular, the impact of temperature on cancer cell cycle dynamics is under explored. We set out to investigate these mechanisms. We employed time lapse confocal microscopy and fluorescence ubiquitin-based cell cycle indicator expressing cancer cell lines to interrogate the effects of temperature on the cell cycle. To complement our investigation, we utilised the open source cancer genomics platforms cBioPortal and XenaBrowser to explore potential molecular determinants of cancer thermosensitivity. Through tracking the breast cancer cell line MCF-7 we observed hyperthermia to result in increased instances of endoreplication and mitotic catastrophe induced cell death. We also highlight components of the T complex protein ring complex as playing a potential role in testicular cancer. These findings will guide design of future cancer thermosensitivity study and may contribute towards novel adjuvant therapeutic cancer strategies

Impact of an anticipatory care planning intervention on unscheduled acute hospital care using difference-in-difference analysis

Acknowledgements We thank Information Statistics Division and the data analytical team from NHS Lothian for data linkage. Funding This work was supported by NHS Lothian through an award from the Invest to Save Fund. The Health Economics Research Unit is funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates.Peer reviewedPublisher PD

catena-Poly[[silver(I)-μ-4-aminopyridine] perchlorate]: a 1-D staircase coordination polymer

Reaction of 4-amino­pyridine with silver(I) perchlorate leads to a one-dimensional coordination polymer, {[Ag(C5H6N2)]ClO4}n, in which the amino­pyridine binds through both N atoms. The perchlorate anion is hydrogen bonded to the amino H atoms and inter­acts weakly with the silver(I) atoms (Ag—O > 2.70 Å), both located on inversion centres, and some aromatic H atoms (O—H > 2.55 ÅA), thereby extending the dimensionality of the assembly. This is the first silver complex in which this ligand acts in a bridging mode

Research Notebooks Workshop

The workshop was a meetup to discuss practical steps for institutions wishing to providing central support for research notebook tools

Research Notebooks Workshop

The workshop was a meetup to discuss practical steps for institutions wishing to providing central support for research notebook tools