Effects of clusterin overexpression on TNFalpha- and TGFbeta-mediated death of L929 cells

Clusterin is a widely distributed and highly conserved protein for which many functions have been proposed. We used transfected L929 cells to study the effect of clusterin expression on the regulation of cell death signals. We showed that high levels of clusterin expression, about 0.2 pg clusterin secreted per cell per 48 h period, specifically protected L929 cells from TNFalpha-mediated cytotoxicity, while low expression (about 4 fg/cell/48 h) had no effect. However, clusterin expression did not provide transfected L929 cells with protection against death mediated by colchicine, staurosporine or azide. High level expression of clusterin in transfected L929 cells also potentiated the cytotoxicity of TGFbeta. It had previously been shown that exposure of L929 cells to TGFbeta provides protection against TNFalpha. We showed that this protective effect is not additive to that of clusterin expression. One interpretation of this data is that it suggests that clusterin and TGFbeta may act via a common mechanism to provide protection against the cytotoxicity of TNFalpha. Our results indicate that an intracellular action of clusterin protein is responsible for protection against TNFalpha cytotoxicity. Exposure to TNFalpha induces an increase in the level of cell-associated clusterin and specifically in the level of a novel clusterin molecule, which when analyzed under reducing conditions by SDS/PAGE and immunoblotting appears as two closely spaced bands at about 36 and 38.5 kDa. When analyzed under the same conditions, the normal form of intracellular clusterin, which is present with or without exposure to TNFalpha, appears as two poorly resolved bands at about 43-45 kDa. Since the novel form of clusterin is also expressed in cells exposed to TGFbeta, colchicine, staurosporine, and azide, it may result from toxin-induced disruption of processes of normal cellular protein production.     

Interleukin-9 promotes allergen-induced eosinophilic inflammation and airway hyperresponsiveness in transgenic mice

Human atopic asthma is a complex heritable inflammatory disorder of the airways associated with clinical signs of allergic inflammation and airway hyperresponsiveness. Recent studies demonstrate that the degree of airway responsiveness is strongly associated with interleukin (IL)-9 expression in murine lung. To investigate the contribution of IL-9 to airway hyperresponsiveness, and to explore directly its relationship to airway inflammation, we studied transgenic mice overexpressing IL-9. In this report we show that IL-9 transgenic mice (FVB/N-TG5), in comparison with FVB/NJ mice, display significantly enhanced eosinophilic airway inflammation, elevated serum total immunoglobulin E, and airway hyperresponsiveness following lung challenge with a natural antigen (Aspergillus fumigatus). These data support a central role for IL-9 in the complex pathogenesis of allergic inflammation.     

T cell receptor alpha gene rearrangement and transcription in adult thymic gamma delta cells

T cells belong to two separate lineages based on surface expression of alpha beta or gamma delta T cell receptors (TCR). Since during thymus development TCR beta, gamma, and delta genes rearrange before alpha genes, and gamma delta cells appear earlier than alpha beta cells, it has been assumed that gamma delta cells are devoid of TCR alpha rearrangements. We show here that this is not the case, since mature adult, but not fetal, thymic gamma delta cells undergo VJ alpha rearrangements more frequently than immature alpha beta lineage thymic precursors. Sequence analysis shows VJ alpha rearrangements in gamma delta cells to be mostly (70%) nonproductive. Furthermore, VJ alpha rearrangements in gamma delta cells are transcribed normally and, as shown by analysis of TCR beta-/- mice, occur independently of productive VDJ beta rearrangements. These data are interpreted in the context of a model in which precursors of alpha beta and gamma delta cells differ in their ability to express a functional pre-TCR complex.     

Effect of acute and chronic arecoline treatment on cerebral metabolism and blood flow in the conscious rat

To investigate the structural contribution of the light chain of anti-DNA antibodies to fine specificity, the VKappa genes of two monoclonal anti-DNA antibodies, termed H241 and H102, were cloned and sequenced. H102 and H241 are independently derived from MRL-lpr/lpr mice and differ in their fine specificity: H241 binds dsDNA and normal glomeruli in vitro and deposits in the kidney in vivo, whereas H102 binds only ssDNA and does not deposit in the kidney. Both are encoded by nearly identical VH genes but different N and D regions. Our previous results have demonstrated that the VH gene for H102 and H241 encodes eight other anti-DNA antibodies that also differed in fine specificity. This suggested that the gene product encoded by the VH 102/241 gene, may have intrinsic affinity for DNA, but is unlikely to determine fine specificity or nephritogenicity. In the present study we examined whether the VKappa gene might account for the difference in nephritogenicity. The complete nucleotide and deduced amino acid sequence of VK 102 and VK241 revealed that they are very dissimilar to each other (< 60% homology). VK 241 defined a new member of the VKappa gene family and was moderately homologous to two other VK genes encoding anti-DNA antibodies and to one VK gene encoding an anti-histone antibody all from lupus strains of mice. In addition, sequence diversity in the VK CDR1 region and position 96 of the CDR3 region was observed that may be of significance in determining fine specificity. VK 102 was highly homologous to two other VKappa genes, VKs17.2 and VK C8.5, both encoding anti-DNA antibodies and members of the VK20 gene family. It was striking that all three members of the VK 20 gene family code for DNA reactivity. This suggests that certain VKappa genes may also be used to repeatedly code for anti-DNA reactivity.     

Female multiple mating behaviour in the common shrew as a strategy to reduce inbreeding

Three hypotheses concerning potential genetic benefits of female multiple mating behaviour are evaluated for the common shrew. In a high-density population, many successful copulations took place between individuals estimated to be close relatives (e.g. full or half siblings). Juveniles resulting from such matings tended to be relatively small at weaning, and were generally less likely to survive to sexual maturity than more outbred individuals. Multiple paternity was discovered in eight of nine litters examined. The incidence of matings between close relatives, the cost of inbreeding, and the high incidence of multiple paternity presented are each consistent with the hypothesis that female multiple mating is a strategy to reduce inbreeding. That is, if females cannot always distinguish close kin, then they may copulate with several different males and so reduce the risk that all their offspring will be sired by a close relative.     

Treatment of stable burst fracture of the atlas (Jefferson fracture) with rigid cervical collar

STUDY DESIGN: A retrospective review of a clinical series. OBJECTIVE: To evaluate the use of a rigid cervical collar alone as the treatment for stable Jefferson fracture, and to devise an algorithm for treatment of Jefferson fracture with or without an associated cervical injury. SUMMARY OF BACKGROUND DATA: The traditional treatment for Jefferson fracture, if there is no indication for surgery, is immobilization by halo vest. Because halo vest placement is associated with intracranial infection and a significant degree of patient discomfort, slightly less rigid forms of external immobilization may be useful for the treatment of stable Jefferson fractures. No standard protocol calling for the use of one form of stabilization device has been reported. MATERIALS: The medical records and radiographs of 16 consecutive patients with Jefferson fracture during a 2-year period were reviewed. Each patient underwent a complete cervical radiograph series and a computed tomographic scan. The mean C1 lateral mass displacement was 1.8 mm. Cervical spine radiographs, including lateral flexion-extension views were obtained 10 to 12 weeks after injury before the removal of an external immobilization device. RESULTS: Of these 16 patients, 1 sustained a complete injury, and 7 sustained an incomplete injury. Eight patients were neurologically intact. Twelve patients sustained a stable Jefferson fracture and were treated with a rigid cervical collar (Miami-J collar [Jerome Medical, Moorestown, NJ]) alone from 10 to 12 weeks. The patient sustaining the complete neurologic injury died of multisystem trauma. All 15 live patients showed no instability on their follow-up plain radiographs before the removal of an external stabilization device. Six patients underwent further plain radiographs approximately 1 year after the fracture and similarly demonstrated no instability. CONCLUSIONS: Isolated stable burst fracture of the atlas can be treated effectively with a rigid cervical collar alone for 10 to 12 weeks with good neurologic recovery and segmental stability. Unstable Jefferson fractures with concurrent unstable fracture of other cervical vertebrae, especially C2, requires surgical stabilization.     

The quality of life of diabetics

The purposes of this study were to identify the meaning of the quality of life for the people who suffer from Diabetes Mellitus, to recognize the aspects which affect most their lives due to this disease and the degree of the satisfaction in their lives as well. Participated in this research forty-six (46) diabetic patients, adults of both sexes, who were in a polyclinic for treatment. The results showed that the meaning of the quality of life had priority related to the physical well-being (54.5%), to the social and economical stability (26.0%), and to the spiritual and emotional well-being (16.9%). The most affected aspects due to this disease were: studying and home activities (38.5%) physical ability (25.6%) and family relationship (10.3%). Concerning about the degree of satisfaction with their lives, the majority of them (66.6%) considered themselves satisfied or very satisfied. It is worth while to point out the importance of considering the multimensionality of the concept of quality of life while attending the diabetic person.