Insulation lead failure: is it a matter of insulation coating, venous approach, or both?

Gag gene mutants of human immunodeficiency virus type 1 (HIV-1) were analyzed for their potentials of inhibiting the replication of wild-type (wt) HIV-2, the second AIDS virus, in a single-round of viral replication. Of twenty-two HIV-1 gag mutants examined, seven were found to efficiently interfere with the replication of wt HIV-2. Some mutants, which can suppress the replication of wt HIV-1, did not show this inhibitory effect. These mutants were defective at the late phase of viral replication. A mutant designated NL-C1a was demonstrated to be very effective against the replication of HIV-1 and HIV-2 in monocytic cells as well as in lymphocytic cells.     

Insulin-like growth factor binding protein production in human follicular thyroid carcinoma cells

OBJECTIVE: The study investigated the value of using national or regional data bases to examine care in a specific hospital. DATA SOURCES: The following data sources were included: (1) the results of the 1992 HCFA analysis of the index hospital for patients hospitalized in fiscal year 1990; (2) the 1989 Medicare Provider Analysis and Review (MEDPAR) file; and (3) clinical information from bypass surgery patients in Wisconsin and from the index hospital. PRINCIPAL FINDINGS: The assessment of the mortality rates in the index hospital for all conditions combined and for CABG patients differed depending on what data base was used and how the data were analysed. The national data were most useful in establishing that the coding practices for all patients and the mortality rate for intra-aortic balloon patients differed between the index hospital and other hospitals. The regional clinical data base for bypass surgery patients was used to establish that the high mortality rates for intra-aortic balloon patients were due to patient selection. CONCLUSIONS: National claims data must be analysed carefully before applying results to an individual hospital. Even a careful analysis is more for raising questions about care at a specific hospital rather than for reaching definitive conclusions.     

Mouse deformed epidermal autoregulatory factor 1 recruits a LIM domain factor, LMO-4, and CLIM coregulators

Nuclear LIM domains interact with a family of coregulators referred to as Clim/Ldb/Nli. Although one family member, Clim-2/Ldb-1/Nli, is highly expressed in epidermal keratinocytes, no nuclear LIM domain factor is known to be expressed in epidermis. Therefore, we used the conserved LIM-interaction domain of Clim coregulators to screen for LIM domain factors in adult and embryonic mouse skin expression libraries and isolated a factor that is highly homologous to the previously described LIM-only proteins LMO-1, -2, and -3. This factor, referred to as LMO-4, is expressed in overlapping manner with Clim-2 in epidermis and in several other regions, including epithelial cells of the gastrointestinal, respiratory and genitourinary tracts, developing cartilage, pituitary gland, and discrete regions of the central and peripheral nervous system. Like LMO-2, LMO-4 interacts strongly with Clim factors via its LIM domain. Because LMO/Clim complexes are thought to regulate gene expression by associating with DNA-binding proteins, we used LMO-4 as a bait to screen for such DNA-binding proteins in epidermis and isolated the mouse homologue of Drosophila Deformed epidermal autoregulatory factor 1 (DEAF-1), a DNA-binding protein that interacts with regulatory sequences first described in the Deformed epidermal autoregulatory element. The interaction between LMO-4 and mouse DEAF-1 maps to a proline-rich C-terminal domain of mouse DEAF-1, distinct from the helix-loop-helix and GATA domains previously shown to interact with LMOs, thus defining an additional LIM-interacting domain.     

Experimental comparison of the tuberculostatic activities of INH, INHG and INHG-Na (author''s transl)

A sample of 42 case notes of alcoholic patients were abstracted for 17 items by three different raters. Interrater agreement was generally rather low. Research based on case-note abstraction which does not report on abstraction reliabilities must therefore be viewed with some suspicion. It would be helpful if clinical material could more often be collected in a standardized manner.     

Solid state microdosimetry

A review of solid state microdosimetry is presented with an emphasis on silicon-based devices. The historical foundations and basics of microdosimetry are briefly provided. Various methods of experimental regional microdosimetry are discussed to facilitate a comparison with the more recent development of silicon microdosimetry. In particular, the performance characteristics of a proportional gas counter and a silicon microdosimeter are compared. Recent improvements in silicon microdosimetry address the issues of requirement specification, non-spherical shape, tissue equivalence, sensitive volume definition (charge collection complexity) and low noise requirements which have previously impeded the implementation of silicon-based microdosimetry. A prototype based on silicon-on-insulator technology is described along with some example results from clinical high LET radiotherapy facilities. A brief summary of the applications of microdosimetry is included.     

Intraovarian actions of oestrogen

Oestrogen regulates several hypothalamic and pituitary hormones, which in turn control ovarian functions. Oestrogen and its metabolites, such as catecholoestrogens, also have direct effects within the ovary. This review examines the roles of oestrogen in regulating ovarian folliculogenesis, ovulation and corpus luteum formation. Oestrogen promotes follicular development, which culminates in ovulation, by potentiating follicular development, granulosa cell expression of gonadotrophin receptors, steroidogenesis, and gap junction formation by granulosa cells, and by inhibiting granulosa cell apoptosis. In addition, oestrogen may be needed for corpus luteum formation and maintenance. Studies on mutant mice that either lack one or both of the known oestrogen receptors or are unable to synthesize oestrogen support some but not all of these prior inferences of the roles of oestrogen within the ovary. Although these transgenic mice have proved useful in determining some of the intraovarian actions of oestrogen, they present confounding problems, including hormonal imbalances, that hinder interpretation. Transgenic mice with conditional or tissue-directed mutations in their oestrogen receptors are needed to dissect the ovarian actions of oestrogen further. In addition, microarray technologies, combined with specific hormone treatment regimens are likely to provide an attractive, alternative approach to using mutant mice in clarifying the direct actions of oestrogen in the ovaries of other species.     

The hardness of the Expected Decision Depth problem

Given a function f over n binary variables, and an ordering of the n variables, we consider the Expected Decision Depth problem. Namely, what is the expected number of bits that need to be observed until the value of the function is determined, when bits of the input are observed according to the given order. Our main finding is that this problem is (essentially) #P-complete. Moreover, the hardness holds even when the function f is represented as a decision tree.