Kinin B1 receptor expression and function on human brain endothelial cells

The kinin B1 receptor is an inducible receptor expressed in response to inflammatory mediators. We sought to determine whether kinin B1 receptor can be expressed on human brain endothelial cells (HBECs) in vitro and whether signaling via this receptor can regulate permeability and chemokine production properties of these cells. Multiplex RT-PCR amplification and western blot techniques were used to evaluate B1 receptor expression by HBECs. Although B1 receptor mRNA and protein could not be detected on resting HBECs, interferon-gamma induced a dose- and time-dependent up-regulation of B1 receptor mRNA and protein on HBECs. Stimulation of interferon-gamma-treated HBECs with the selective B1 agonist R-838 (Sar [D-Phe8] des Arg9-BK) induced a dose- and time-dependent increase in the production of inositol 3,4,5 tri-phosphate and nitric oxide. Permeability of the HBECs monolayer, as measured by BSA diffusion, was significantly increased by application of the B1 agonist. This biological effect of R-838 could be prevented by R-715, a B1 receptor antagonist and by L-NAME, a nitric oxide synthase blocker. R-838 also inhibited interleukin-8 release from HBECs. We demonstrate that B1 receptors can be up regulated on the surface of HBECs by molecules released during inflammatory response and that signaling via this receptor can regulate BBB permeability and chemokine production in vitro.     

Acromegaly is associated with a distinct oral and gut microbiota

Pituitary - Our aim was to investigate the changes in the composition of oral and gut microbiota in patients with newly diagnosed acromegaly and their relationship with IGF-1 levels. Oral and fecal...     

Comparative study of the closed reduction percutaneous cannulated screw fixation and open reduction palmar locking plate fixation in the treatment of AO type A2 distal radius fractures

Introduction

The present study was designed to demonstrate the efficacy of standard 4.0 mm cannulated screw fixation by comparing it with palmar locking plate fixation in the treatment of acute, unstable, simple extra-articular distal radius fractures.

Materials and methods

We prospectively collected and retrospectively analyzed outcomes data for 65 patients aged between 18 and 60 with AO type A2 fractures treated with closed reduction, percutaneous cannulated screw fixation (CRPCS n = 34) or open reduction palmar locking plate fixation (ORPLP n = 31). Range of motion, grip strength, Gartland–Werley and QuickDASH scores were compared at 2 months after surgery, and final follow-up (mean 32 months, range 12–90). Deterioration in radiographic parameters were measured and compared. Operative time and return to preinjury activity were evaluated.

Results

Parameters did not differ significantly between the groups at either time point with respect to grip strength or range of motion, except pronation and supination; they were better in the CRPCS group (p = 0.005 and 0.025, respectively) at 2 month follow-up. The Gartland–Werley and QuickDASH scores obtained at final follow-up were similar for each group and lacked statistical significance. Group comparison for the deterioration of radiologic parameters showed no significant difference. CRPCS group had significantly shorter operative time (p = 0.001) and there was no significant differences between the groups regarding the return to preinjury activity (p = 0.129).

Conclusions

CRPCS group was found to be as successful as ORPLP group and it may be suitable in the case of young, active individuals with AO type A2 distal radius fractures.     

Alzheimer's beta-amyloid precursor protein is expressed on the surface of immediately ex vivo brain cells: A flow cytometric study

Beta-amyloid precursor protein (βAPP) is ubiquitously expressed, but deposition of the βAPP proteolytic fragment Aβ is virtually restricted to the brain, suggesting cell-specific processing of this molecule. Our laboratory has investigated expression of βAPP in mechanically dissociated, unfixed, immediately ex vivo cells from various mouse and rat organs by flow cytometry. Epitopes of predicted extracellular domains of βAPP recognized by the N-terminal 22C11 monoclonal antibody (mAb) and the juxtamembrane 4G8 mAb were not detectable on the surface of lymphoid cells, hepatocytes, or kidney cells. In contrast, surface 22C11 and 4G8 βAPP immunoreactivity was abundant on intact (propidium iodide-excluding) dissociated brain cells. The predicted C-terminal intracellular βAPP determinant recognized by the mAb Jonas was not detectable on the surface of intact brain cells, but was present in ethanol-permeabilized cells, consistent with a transmembrane configuration of βAPP in brain cells. Trypsinization of intact brain cells abolished cell surface immunoreactivity for 22C11, which was then reestablished by short-term culture. Augmentation of 22C11 and 4G8 surface immunoreactivity occurred when brain cells were cultured short-term in phenylarsine oxide, a general endocytosis inhibitor. By double staining protocols of brain cells with mAbs directed against βAPP ecto-domain epitopes and the neuronal surface proteins Thy-1 or neural cell adhesion molecule (NCAM), we observed that all Thy-1⁺ and NCAM⁺ cells (∼50%) were immunoreactive for surface βAPP, but that some βAPP⁺ cells (∼20%) were negative for these neuronal markers. Our data suggest that neurons and a subpopulation of other brain cells, unlike peripheral cells, can support βAPP as a type I intrinsic membrane molecule with an intact ectodomain, and that βAPP surface abundance is regulated by an equilibrium between membrane vesicle insertion and endocytotic internalization. Transmembrane βAPP holoprotein may be a critical determinant of brain-predominant processing of βAPP to Aβ, and may participate in a receptor/transducer function unique to brain cells. © 1996 Wiley-Liss, Inc.     

Chondromyxoid fibroma involving the entire metacarpal: a case report

The occurrence of chondromyxoid fibroma in the hand is rare. We report a case of chondromyxoid fibroma involving the whole fourth metacarpal that was treated by curettage and cancellous bone allograft.     

Caspase 8 expression and signaling in Fas injury-resistant human fetal astrocytes

Fas (APO-1/CD95) is a cell surface receptor initially identified in lymphoid cells, but more recently detected in the central nervous system under pathological, usually inflammatory, conditions. In most Fas expressing cells, triggering of Fas by its ligand or by antagonistic antibodies leads to apoptosis. Human fetal astrocytes (HFA) constitutively express Fas yet are resistant to cell death following Fas ligation. In the current study, using dissociated cultures of human fetal central nervous system-derived cells, we attempted to identify a basis for HFA resistance to Fas-mediated injury. We compared the components of the Fas signaling pathway of HFA to those of two human cell lines susceptible to Fas-mediated injury, U251 glioma and Jurkat T-cells. We found that HFA did not express caspase 8 (FLICE), the caspase primarily activated on Fas signaling. Although we could induce caspase 8 in HFA with the inflammatory cytokines IFNgamma and TNFalpha, HFA remained resistant to Fas-mediated injury. Addition of inflammatory cytokines to the extracellular milieu also increased FLIP mRNA (FLICE inhibitory protein). Furthermore, upon triggering of cytokine-treated cells with FasL, we observed upregulation of the cleavage product of FLIP (p43-FLIP) previously shown to associate with the DISC and to block caspase 8 recruitment, thereby inhibiting Fas-mediated death. Our findings indicate that caspase 8 and its regulators play a central role in determining the response to Fas ligation of HFA and support a role for Fas signaling in the developing central nervous system other than related to cytotoxicity.     

Lack of association between two restriction fragment length polymorphisms in the genes for the light and heavy neurofilament proteins and Alzheimer's disease

The etiology of Alzheimer disease (AD) remains unknown. The hypothesis of genetic factors playing a role in the causation of the disease, at least in its familial form, has been borne out by results showing linkage in several early-onset AD families to a locus on the proximal part of the long arm of chromosome 21. Linkage was not detected in several other families using the same markers. The metabolism of neurofilaments is perturbed in AD, as indicated by the presence of neurofilament epitopes in neurofibrillary tangles, as well as by the severe reduction of the expression of the gene for the light neurofilament subunit in AD brain. To detect a possible anomaly that might relate to the disease, we have searched for an association between the genes for the light subunit and the heavy subunit of the neurofilament triplet, and AD. Genotypes for restriction fragment length polymorphisms (RFLP) at each of the two loci were determined for an AD group and a control group. Allelic frequencies at a TaqI-defined RFLP for the gene for the light neurofilament subunit were 0.70 for the 3.7 kb allele and 0.30 for the 2.9 kb allele. HincII detected an RFLP for the heavy neurofilament subunit gene with frequencies of 0.31 for the 18.0 kb allele and 0.69 for the 6.8 kb allele. Frequencies were found to be similar in the two groups for both light and heavy neurofilament subunit loci. Although it cannot be excluded that mutations at other sites of the neurofilament genes are relevant to AD, the data reported here do not support an association between these genes and the disease.     

Dystrophin expression in muscle following gene transfer with a fully deleted ("gutted") adenovirus is markedly improved by trans-acting adenoviral gene products

Helper-dependent adenoviruses (HDAd) are Ad vectors lacking all or most viral genes. They hold great promise for gene therapy of diseases such as Duchenne muscular dystrophy (DMD), because they are less immunogenic than E1/E3-deleted Ad (first-generation Ad or FGAd) and can carry the full-length (Fl) dystrophin (dys) cDNA (12 kb). We have compared the transgene expression of a HDAd (HDAdCMVDysFl) and a FGAd (FGAdCMV-dys) in cell culture (HeLa, C2C12 myotubes) and in the muscle of mdx mice (the mouse model for DMD). Both vectors encoded dystrophin regulated by the same cytomegalovirus (CMV) promoter. We demonstrate that the amount of dystrophin expressed was significantly higher after gene transfer with FGAdCMV-dys compared to HDAdCMVDysFl both in vitro and in vivo. However, gene transfer with HDAdCMVDysFl in the presence of a FGAd resulted in a significant increase of dystrophin expression indicating that gene products synthesized by the FGAd increase, in trans, the amount of dystrophin produced. This enhancement occurred in cell culture and after gene transfer in the muscle of mdx mice and dystrophic golden retriever (GRMD) dogs, another animal model for DMD. The E4 region of Ad is required for the enhancement, because no increase of dystrophin expression from HDAdCMVDysFl was observed in the presence of an E1/E4-deleted Ad in vitro and in vivo. The characterization of these enhancing gene products followed by their inclusion into an HDAd may be required to produce sufficient dystrophin to mitigate the pathology of DMD by HDAd-mediated gene transfer.     

Characteristics of synchronous- and metachronous-type multiple primary neoplasms: a study of hospital-based cancer registry in Turkey

PURPOSE: The aim of this study was to evaluate the demographic, histologic, and topographic characteristics, and the association of synchronous and metachronous multiple primary neoplasms. PATIENTS AND METHODS: Five hundred seventy-two multiple primary tumors (n = 286) of 20,895 tumors recorded from 1993 to 2005 by the office of Izmir Cancer Registry at the Izmir Ataturk Training and Research Hospital were analyzed. chi(2) and Student t test were performed. RESULTS: One hundred fifty-eight patients had synchronous tumors whereas 128 had metachronous tumors. Both groups were more frequent among men and among patients aged > 50 years. The distribution of synchronous and metachronous tumors between sex and age groups was similar (P = .462 and P = .479, respectively). Carcinomas were more frequent and histologic compositions of both of the groups were significantly different (P = .009). Pairs of the same topographic origin were significantly more frequent in synchronous tumors (P = .019). The urogenital system was the most frequent location in all groups. The leading tumoral association was between urogenital-urogenital tumors, also. Detailed evaluation of the metachronous group revealed that the most frequent organ associations were of breast-ovary (n = 7) and bladder-larynx (n = 5). CONCLUSION: Field cancerization in the epithelium, theory of a common clonal origin, or the screening effect might account for the relatively frequent association of urogenital tumors. The association of the tumors of breast-ovary might be related to the endocrine effect. Further studies complying with international rules and using data from different population-based tumor registries are necessary to elucidate site correlation.