Seminiferous tubule transfection in vitro to define post-meiotic gene regulation

Background  

Post-meiotically expressed genes in the testis are essential for the proper progression of spermatogenesis, and yet, aside from the construction of individual transgenic mice using specific promoters to drive reporter plasmids, there are only very limited possibilities for relevant and quantitative analysis of gene promoters. This is due to the special nature of post-meiotic haploid cells, which to date are not represented in any appropriate cell-lines. This article reports the development of novel methodology using isolated and cultured rat seminiferous tubules in a multiwell format, into which promoter-reporter constructs can be introduced by a combination of microinjection and electroporation.     

Declining incidence of AIDS dementia complex after introduction of zidovudine treatment.

OBJECTIVE--To assess the incidence of the AIDS dementia complex and the presence of HIV I p24 antigen in cerebrospinal fluid in relation to zidovudine treatment. DESIGN--Retrospective study of a consecutive series of patients with AIDS from 1982 to 1988. SETTING--An academic centre for AIDS. PATIENTS--196 Patients with AIDS and neurological symptoms examined from 1982 to 1988. INTERVENTIONS--Zidovudine treatment, which was introduced to The Netherlands on 1 May 1987 for patients with severe symptoms of HIV infection (Centers for Disease Control groups IVA, B, C, and D). MAIN OUTCOME MEASURES--Diagnosis of AIDS dementia complex and presence of HIV I p24 antigen in cerebrospinal fluid. RESULTS--The AIDS dementia complex was diagnosed in 40 of the 196 (20%) patients with AIDS. Thirty eight of 107 patients with AIDS (36%) not taking zidovudine developed the AIDS dementia complex compared with two of the 89 (2%) taking the drug (p less than 0.00001). The incidence of the AIDS dementia complex increased to 53% in the first half of 1987, after the introduction of zidovudine in May 1987, decreasing to 10% in the second half of 1987 and to 3% in 1988. Dementia was diagnosed before definition of the AIDS dementia complex (1986) according to DSM-III criteria and there was good agreement between diagnosis before and after 1986. Sixteen of 61 samples of cerebrospinal fluid (26%) from patients with AIDS (10 with the AIDS dementia complex) not taking zidovudine were positive for HIV I p24 antigen, whereas none of 37 cerebrospinal fluid samples from patients with AIDS (two with the AIDS dementia complex) taking zidovudine were positive. CONCLUSIONS--The incidence of AIDS dementia complex in patients with AIDS declined after the introduction of systematic treatment with zidovudine; the AIDS dementia complex might be prevented by inhibiting viral replication in the central nervous system.     

Oxide-Based Solid-State Batteries: A Perspective on Composite Cathode Architecture

The garnet-type phase Li₇La₃Zr₂O₁₂ (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs.     

Interaction of glutathione analogues with Hydra attenuata gamma-glutamyltransferase.

gamma-Glutamyltransferase activity was studied in extracts of the cnidarian Hydra attenuata. The binding of gamma-glutamyl peptide analogues to the enzyme was studied by observing their effects on heat denaturation and their inhibition of p-nitroaniline release from gamma-glutamyl p-nitroanilide. Neither position-1 analogues, in which the gamma-glutamyl moiety was changed to a beta-aspartyl (beta-Asp-Abu-Gly) or an alpha-glutamyl (Glu-Abu-Gly) linkage, nor glutamate protected the enzyme against inactivation at 58 degrees C. GSH (reduced glutathione), gamma-Glu-Abu-Gly and gamma-Glu-Met on the other hand did prevent heat denaturation. GSH and analogues of GSH were competitive inhibitors of p-nitroaniline release, but those analogues in which glycine was replaced by 2-aminoisobutyrate, phenylalanine, leucine or tyrosine had Ki values that were approximately five times those of analogues with the cysteine residue replaced.     

Macromolecular synthesis in human diploid fibroblasts. A viral probe examining the effect of in vivo aging.

The replication of vesicular stomatitis virus was examined in early-passage skin fibroblast cultures from old and young human donors. The production of virus was analysed by measuring synthesis of viral RNA in actinomycin D-treated cells, and by determining the yield of biologically-active viral progeny by plaque assay. Although no statistically significant differences (P < 0.05) were observed between old and young cultures, our assays were shown to be capable of detecting impaired macromolecular synthesis induced by incorporation of amino acid analogues. These results indicate that macromolecular synthesis does not appear to be significantly altered in cells from older donors.     

Über die Wirkung langdauernder peroraler Verabreichung von Follikelhormon auf die Nebenniere der weissen Maus

Ohne Zusammenfassung     

Gene flow and range expansion in a mountain‐dwelling passerine with a fragmented distribution

We studied gene flow and bottleneck events in the population history of locally isolated citril finches endemic to European mountains. For the present study, we used two genetic markers with different rates of evolution: a fast evolving mitochondrial marker (ATPase6/8) and a more slowly evolving nuclear marker (02401). Populations north of the Pyrenees showed in general fewer haplotypes and a considerable lower nucleotide and gene diversity than the Iberian populations. Unexpectedly, we found very little genetic variability in the fast evolving mitochondrial marker, arguing for a strong and relatively recent bottleneck event in the species population history. This pattern potentially reflects a sudden decrease of crucial resources during Mid‐Holocene (mountain pine, Scots pine, and black pine) and a subsequent breakdown of the population. The bottleneck could also have been caused or coincide with a selective sweep in the mitochondrion. By contrast, the slowly evolving nuclear marker showed a much higher variability. This marker probably reflects major gene flow along a potential expansion pathway from the Eastern Pyrenees, northwards to the populations of Central Europe, and southwards to the more fragmented populations of central and southern Spain. The population of the Western Pyrenees (Navarra) appears to be cut‐off from this major gene flow and our data indicate a certain degree of partial isolation, probably reflecting more ancient events (e.g. the separation in distinct refuge sites during the last glacial maximum). © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 707–721.