Evidence for a role of mast cells in the mucosal injury induced by Newcastle disease virus

We have previously demonstrated that mast cells were significantly increased during Newcastle disease virus (NDV) infection, but their precise role in the process is unknown. In this study, we investigated the role of mast cells in this process by using ketotifen, a mast cell membrane stabilizer. A total of 60 specific-pathogen-free chickens were randomly divided into 3 groups of 20 birds each (NDV-infected group, ketotifen-pretreated group, and the control group). The ketotifen-pretreated group was administered orally with ketotifen before NDV infection. On 12, 24, and 48 h postinfection, 5 chickens from each treatment were killed. Tissues of proventriculus were collected to quantify mast cells, the content of tryptase and histamine by cytochemistry, immunohistochemistry, and fluorescence analysis, respectively. The results showed that the population of mast cells and the content of tryptase and histamine were increased significantly in the proventriculus (P < 0.01) of infected birds compared with the control group. An acute mucosal injury was observed in the infected chickens. In contrast, among chickens pretreated with ketotifen, followed by NDV infection, the mast cells number and the content of tryptase and histamine were decreased significantly (P < 0.01). Likely as a result, the mucosal injury was remitted remarkably. The overall results of this experiment suggest that mast cells are implicated in NDV-induced mucosal injury. Inhibition of mast cell mediator release may represent a novel strategy to modulate this process.

EDA gene mutations underlie non-syndromic oligodontia

Recent studies have detected mutations in the EDA gene, previously identified as causing X-linked hypohidrotic ectodermal dysplasia (XLHED), in two families with X-linked non-syndromic hypodontia. Notably, all affected males in both families exhibited isolated oligodontia, while almost all female carriers showed a milder or normal phenotype. We hypothesized that the EDA gene could be responsible for sporadic non-syndromic oligodontia in affected males. In this study, we examined 15 unrelated males with non-syndromic oligodontia. Three novel EDA mutations (p.Ala259Glu, p. Arg289Cys, and p.Arg334His) were identified in four individuals (27%). A genetic defect in the EDA gene could result in non-syndromic oligodontia in affected males.

Effects of Chinese Herb Danshen-Dahuang on Hippocampal Gene Expression of APP and PS1 in Rats with Alzheimer Disease

Aims:

To investigate the effect of Chinese herb Danshen-Dahuang on learning and memory ability in rats with Alzheimer disease (AD) induced by D-galactose and AlCl3 and its possible mechanisms.

Methods:

The AD model was produced by injecting D-galactose and AlCl3 intraperitoneally for 90 days. Since the 20th day of D-galactose and AlCl3 intraperitoneal injection, the rats in Danshen-Dahuang group had been treated with Danshen-Dahuang extraction by intragastric administration for 70 days. Subsequently,learning and memory ability of the mice was evaluated by Morris water maze and hippocampal gene expression of APP, PS1 was tested by reverse transcription polymerase chain reaction (RT-PCR).

Results:

Rats intragastric administration with Danshen-Dahuang, mice had shorter latency (P< 0.05) and less error times (P< 0.05) in water maze test compared with those in AD model group. At the same time, Danshen-Dahuang down regulated the expression of APP, PS1 mRNA (P< 0.05) in hippocampus.

Conclusions:

Danshen-Dahuang improves the learning and memory ability of AD rats, its mechanism may be related to the downregulated expression of APP, PS1 mRNA.

An evaluation of four phylogenetic markers in Nostoc: implications for cyanobacterial phylogenetic studies at the intrageneric level

The success of some phylogenetic markers in cyanobacteria owes to the design of cyanobacteria-specific primers, but a few studies have directly investigated the evolution "behavior" of the loci. In this study, we performed a case study in Nostoc to evaluate rpoC1, hetR, rbcLX, and 16S rRNA-tRNA(Ile)-tRNA(Ala)-23S rRNA internal transcribed spacer (ITS) as phylogenetic markers. The results indicated that the gene trees of these loci are not congruent with the phylogeny based on 16S rRNA gene. The mechanisms contributing to the incongruence include randomized variation and recombination. As the results suggested, one should be careful to choose the molecular markers for phylogenetic reconstruction at the intrageneric level in cyanobacteria.

Inhibition of the development of collagen-induced arthritis in Wistar rats through vagus nerve suspension: a 3-month observation

OBJECTIVE AND DESIGN

In this study, we have investigated the effects of vagus nerve suspension in a rat model of collagen-induced arthritis (CIA) .

MATERIALS AND TREATMENT

CIA was induced in male Wistar rats and vagus nerve suspension or sham operation was performed on day 10 after the second immunization. All rats were monitored for macroscopic signs of clinical arthritis and cytokine titres within 2 months after the second immunization. Radiological and histological examination were performed 3 months after the second immunization.

RESULTS

Rats subjected to vagus nerve suspension (the test group) showed nerve activities that resemble electrical stimulation of the vagus nerve in the control group. Compared to control, the test group had reduced soft-tissue swelling, arthritic scores, TNF-alpha level and Collagen-II antibody titre, throughout the course of the experiment. Sham operation produced similar suppression on the CIA symptoms as the test group but most of the effects produced by sham operation subsided after 27 or 35 days.

CONCLUSION

Vagus nerve suspension is a novel approach to achieve sustained long-term stimulation of the vague nerve. This procedure can suppress the development of CIA in rats.

Coupling between neuronal nitric oxide synthase and glutamate receptor 6-mediated c-Jun N-terminal kinase signaling pathway via S-nitrosylation contributes to ischemia neuronal death

S-nitrosylation, as a post-translational protein modification, recently has been paid more and more attention in stroke research. S-nitrosylation regulates protein function by the mechanisms of covalent attachment that control the addition or the removal of nitric oxide (NO) from a cysteine thiol. The derivation of NO is established by the demonstration that, in cerebral neurons, NO mainly generates from neuronal nitric oxide synthase (nNOS) during the early stages of reperfusion. In the past researches, we demonstrate that global ischemia-reperfusion facilitates the activation of glutamate receptor 6 (GluR6) -mediated c-Jun N-terminal kinase (JNK) signaling pathway. The objective of this study is primarily to determine, during the early stages of reperfusion in rat four-vessel occlusion (4-VO) ischemic model, whether nNOS-derived NO affects the GluR6-mediated JNK signaling route via S-nitrosylation which is performed mainly by the biotin switch assay. Here, we show that administration of 7-nitroindazole, an inhibitor of nNOS, or ketamine, an antagonist of N-methyl-d-aspartate receptor (NMDAR), diminishes the increased S-nitrosylation of GluR6 induced by cerebral ischemia-reperfusion. In contrast, 2-amion-5,6-dihydro-6-methyl-4H-1,3-thiazine, an inhibitor of inducible NO synthase does not affect S-nitrosylation of GluR6. Moreover, treatment with sodium nitroprusside (SNP), an exogenous NO donor, increases the S-nitrosylation and phosphorylation of nNOS, leading to the attenuation of the increased S-nitrosylation of GluR6 and the assembling of GluR6* postsynaptic density protein 95 (PSD95)* mixed lineage kinase 3 (MLK3) signaling module induced by cerebral ischemia-reperfusion. The results also show that GluR6 downstream MLK3* mitogen activated protein kinase kinase 4/7* JNK signaling module and nuclear or non-nuclear apoptosis pathways are involved in the above signaling route. However, dithiothreitol (DTT) antagonizes the neuroprotection of SNP. Treatment with DTT alone, as a negative control, prevents S-nitrosylation of proteins, which indicates the existence of endogenously produced S-nitrosylation. These data suggest that GluR6 is S-nitrosylated by endogenous NO in cerebral ischemia-reperfusion, which is possibly correlated with NMDAR* PSD95* nNOS signaling module, and further activates GluR6* PSD95* MLK3 signaling module and JNK signaling pathway. In contrast, exogenous NO donor antagonizes the above action of endogenous NO generated from nNOS. Thus, our results provide the coupling of nNOS with GluR6 by S-nitrosylation during the early stages of ischemia-reperfusion, which can be a new approach for stroke therapy.

Combined islet and hematopoietic stem cell allotransplantation: a clinical pilot trial to induce chimerism and graft tolerance

To prevent graft rejection and avoid immunosuppression-related side-effects, we attempted to induce recipient chimerism and graft tolerance in islet transplantation by donor CD34+hematopoietic stem cell (HSC) infusion. Six patients with brittle type 1 Diabetes Mellitus received a single-donor allogeneic islet transplant (8611 +/- 2113 IEQ/kg) followed by high doses of donor HSC (4.3 +/- 1.9 x 10(6) HSC/kg), at days 5 and 11 posttransplant, without ablative conditioning. An 'Edmonton-like' immunosuppression was administered, with a single dose of anti-TNFalpha antibody (Infliximab) added to induction. Immunosuppression was weaned per protocol starting 12 months posttransplant. After transplantation, glucose control significantly improved, with 3 recipients achieving insulin-independence for a short time (24 +/- 23 days). No severe hypoglycemia or protocol-related adverse events occurred. Graft function was maximal at 3 months then declined. Two recipients rejected within 6 months due to low immunosuppressive trough levels, whereas 4 completed 1-year follow-up with functioning grafts. Graft failure occurred within 4 months from weaning (478 +/- 25 days posttransplant). Peripheral chimerism, as donor leukocytes, was maximal at 1-month (5.92 +/- 0.48%), highly reduced at 1-year (0.20 +/- 0.08%), and was undetectable at graft failure. CD25+T-lymphocytes significantly decreased at 3 months, but partially recovered thereafter. Combined islet and HSC allotransplantation using an 'Edmonton-like' immunosuppression, without ablative conditioning, did not lead to stable chimerism and graft tolerance.

A survey of emergency medicine in 36 countries

OBJECTIVE

To assess the current level of development of emergency medicine (EM) systems in the world.

DESIGN

Survey of EM professionals from 36 countries during a 90-day period from Aug. 25 to Nov. 24, 1998.

PARTICIPANTS

Thirty-six EM professionals from 36 countries and 6 continents completed the survey. Thirty-five (97%) were physicians, of whom 25 (69%) gave presentations at 1 of 4 international EM conferences during the study period. Three potential participants from 3 countries were excluded because of language barriers. Five additional participants from 5 other countries did not respond within the study period and were excluded.

MEASUREMENTS

Respondents completed a 103-question questionnaire about the presence of EM specialty, academic, patient care, information and management systems and the factors influencing the future of EM in their countries.

RESULTS

The overall response rate was 88%. Nearly all respondents (97%) stated that their countries had hospital-based emergency departments (EDs). More than 80% of respondents reported that their countries have emergency medical services (EMS), national EMS activation phone numbers and ED systems for pediatric emergency care. More than 70% stated that their countries had national EM organizations, EM research, ED systems for patient transfer and peer review and emergency physician (EP) training in Advanced Cardiac Life Support (ACLS) and the ability to perform rapid sequence intubation. More than 60% reported ED systems for trauma care and triage and EP training in Advanced Trauma Life Support (ATLS) and the ability to perform thrombolysis for acute myocardial infarction. Fifty percent reported EM residency training programs, official recognition of EM as an independent specialty, and EM journals.

CONCLUSIONS

Basic emergency medicine components now exist in the majority of countries surveyed. These include many specialty, academic, patient care and administrative systems. The foundation for further EM development is widely established throughout the world.

Vertebroplasty: magnetic resonance findings related to cement leakage risk

PURPOSE

To find magnetic resonance (MR) findings predicting cement leakage in patients receiving percutaneous vertebroplasty (PVP) due to osteoporotic compression fractures.

MATERIAL AND METHODS

MR was done in 43 patients (age 52-89 years) before PVP (56 vertebrae), which was done via a bipedicular approach with fluoroscopic monitoring. Shortly after the procedure, a non-contrast-enhanced computed tomography (CT) scan was done at the vertebroplasty sites for evaluation of bone cement leakage. The following MR findings of fractured vertebral bodies were retrospectively reviewed for correlation with leakage risk: severity of bone-marrow edema, presence of a T2-weighted low-signal-intensity line, percentage residual vertebral body height, presence of either a vacuum or cystic change within the vertebral body, and presence of a cortical disruption.

RESULTS

After PVP, cement leakage was detected in 35 vertebrae (62.5%). Leakage was most frequently observed in the anterior external vertebral venous plexus (46%). Cement leakage rate increased when there was a cortical disruption (P = 0.037), especially at the endplates, while it decreased when there was a vacuum or a cystic change within the fractured vertebra (P = 0.019). Other MR findings were not related to the risk of cement leakage.

CONCLUSION

The risk of cement leakage in PVP increases when MR shows cortical disruption in a fractured vertebral body, especially at the endplates. It decreases when MR shows a vacuum or cystic change within the body.

Mutations Stabilize Small Subunit Ribosomal RNA in Desiccation-Tolerant Cyanobacteria Nostoc

The ribosomal RNA molecule is an ideal model for evaluating the stability of a gene product under desiccation stress. We isolated 8 Nostoc strains that had the capacity to withstand desiccation in habitats and sequenced their 16S rRNA genes. The stabilities of 16S rRNAs secondary structures, indicated by free energy change of folding, were compared among Nostoc and other related species. The results suggested that 16S rRNA secondary structures of the desiccation-tolerant Nostoc strains were more stable than that of planktonic Nostocaceae species. The stabilizing mutations were divided into two categories: (1) those causing GC to replace other types of base pairs in stems and (2) those causing extension of stems. By mapping stabilizing mutations onto the Nostoc phylogenetic tree based on 16S rRNA gene, it was shown that most of stabilizing mutations had evolved during adaptive radiation among Nostoc spp. The evolution of 16S rRNA along the Nostoc lineage is suggested to be selectively advantageous under desiccation stress.

Ischemic preconditioning negatively regulates plenty of SH3s-mixed lineage kinase 3-Rac1 complex and c-Jun N-terminal kinase 3 signaling via activation of Akt

Activation of Akt/protein kinase B has been recently reported to play an important role in ischemic tolerance. We here demonstrate that the decreased protein expression and phosphorylation of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) underlie the increased Akt-Ser-473 phosphorylation in the hippocampal CA1 subfield in ischemic preconditioning (IPC). Co-immunoprecipitation analysis reveals that Akt physically interacts with Rac1, a small Rho family GTPase required for mixed lineage kinase 3 (MLK3) autophosphorylation, and both this interaction and Rac1-Ser-71 phosphorylation induced by Akt are promoted in preconditioned rats. In addition, we show that Akt activation results in the disassembly of the plenty of SH3s (POSH)-MLK3-Rac1 signaling complex and down-regulation of the activation of MLK3/c-Jun N-terminal kinase (JNK) pathway. Akt activation results in decreased serine phosphorylation of 14-3-3, a cytoplasmic anchor of Bax, and prevents ischemia-induced mitochondrial translocation of Bax, release of cytochrome c, and activation of caspase-3. The expression of Fas ligand is also decreased in the CA1 region. Akt activation protects against apoptotic neuronal death as shown in TUNEL staining following IPC. Intracerebral infusion of LY294002 before IPC reverses the increase in Akt phosphorylation and the decrease in JNK signaling activation, as well as the neuroprotective action of IPC. Our results suggest that activation of pro-apoptotic MLK3/JNK3 cascade can be suppressed through activating anti-apoptotic phosphoinositide 3-kinase/Akt pathway induced by a sublethal ischemic insult, which provides a functional link between Akt and the JNK family of stress-activated kinases in ischemic tolerance.

Prevention and treatment of experimental autoimmune encephalomyelitis with recombinant adeno-associated virus-mediated α-melanocyte-stimulating hormone-transduced PLP139-151-specific T cells

The aim of this study was to investigate the immunomodulatory effects and mechanism of action of alpha-melanocyte-stimulating hormone (alpha-MSH) gene modified proteolipid protein (PLP) 139-151-specific T cells (T(PLP-alpha-MSH)) in the SJL mouse model of experimental autoimmune encephalomyelitis (EAE). PLP139-151-specific T cells (T(PLP) cells) were transduced with a recombinant adeno-associated virus 2 (rAAV2) encoding alpha-MSH. After activation with PLP139-151 in vitro, T(PLP-alpha-MSH) cells secreted high levels of alpha-MSH and also demonstrated an altered Th1-like cytokine pattern as well as a high frequency of CD4(+)CD25(+)Treg cells. Transfer studies showed that T(PLP-alpha-MSH) cells could suppress the induction of adoptive transfer EAE. More importantly, our studies demonstrated that T(PLP-alpha-MSH) cells had preventive and therapeutic effect on active relapse-remitting EAE (REAE) in an antigen-inducible manner. Suppression of REAE by T(PLP-alpha-MSH) cells was associated with a general reduction of inflammatory central nervous system (CNS) infiltrates, a pronounced decrease in Th1 cytokines and chemokines expression and an increase in Th2 cytokines. These data strongly suggested that local delivery of alpha-MSH by rAAV2-mediated alpha-MSH-transduced PLP139-151-specific T cells (T(PLP-alpha-MSH)) would be a desirable new approach to the treatment of autoimmune disease in the CNS.