The Peyer's patch is a critical immunoregulatory site for mucosal tolerance in experimental autoimmune encephalomylelitis (EAE)

Expression of MCP-1 in the central nervous system (CNS) is associated with various neuroinflammatory diseases, including multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE). In this study, we found that MCP-1 was decreased in the CNS but increased in the gut following oral administration of myelin basic protein (MBP) correlating with protection from EAE. To study the trafficking and the fate of T cells during oral tolerance, MBP-specific TCR transgenic (Tg) CD4(+) T cells were labeled using 5,6-carboxy-succinimidyl-fluorescein-ester (CFSE) and transferred intravenously to syngeneic B10.PL recipients before feeding with either MBP or PBS. We observed that the CFSE-labeled T cells traffic to the peripheral lymphoid tissue and the Peyer's patches (PP). The labeled T cells proliferate in vivo in both the lymph node and the PP 48h after MBP feeding, but the cells are maintained in the PP longer than in the LN. CFSE-labeled cells in the PP have high levels of CD69 and Fas expression which is accompanied by increased apoptosis after MBP feeding. Our observations suggest that oral administration of autoantigen induces an elevation of MCP-1 in the gut, early T cell trafficking and activation in the periphery and the PP, followed by deletion of autoreactive T cells in the PP.     

真核表达人呼吸道合胞病毒F蛋白的纯化方法

目的 真核表达人呼吸道合胞病毒(human respiratory syncytial virus,SV)融合蛋白(fusion protein,),并完成蛋白纯化及纯度测定.方法 根据编码F蛋白的基因序列设计引物,CR方法扩增出3'端带His标签的F基因序列,克隆入pGEM-T-easy载体,经核酸序列分析后,进一步克隆到pcDNA3.1( )真核表达载体,限制性内切酶鉴定,用脂质体Lipofectamine2000转染COS-7细胞,2 h后再用Westem blot检测目的蛋白的表达.Ni柱亲和层析纯化COS-7细胞表达的F蛋白,高效毛细管电泳分析纯化后蛋白纯度.结果 核酸序列分析证实获得带His标签的RSV F基因序列,没有发生无义突变.转染COS-7细胞后,利用Western blot方法检测到F蛋白的特异性条带,纯度达99%以上.结论 初步建立了真核表达RSV F蛋白的纯化方法,为进一步优化RSV F蛋白制备条件及单克隆抗体及诊断试剂等研究奠定了基础.     

Activation of Vbeta8 T cells affects spontaneous EAE in MBP TCR transgenic mice

Two strains of transgenic (Tg) mice (Valpha2.3/Vbeta8.2 and Valpha4/Vbeta8.2) have T cell receptors (TCR) that recognize the NAc1-11 immunodominant epitope of the myelin basic protein (MBP). Spontaneous experimental autoimmune encephalomyelitis (sEAE) readily develops in Valpha2.3/Vbeta8.2 mice. T cells in Valpha2.3/Vbeta8.2 mice demonstrate increased levels of CD69, CD44(high) and decreased CD45RB relative to Valpha4/Vbeta8.2 mice. Increased proliferative responses to MBP and high levels of TNF-alpha are seen in Valpha2.3/Vbeta8.2 mice. High IL-4 and TGF-beta production is observed in Valpha4/Vbeta8.2 mice. CC chemokines (macrophage inflammatory protein-1 alpha (MIP-1alpha), RANTES and monocyte chemotactic protein 1 (MCP-1)) are increased in the central nervous system (CNS) of Valpha2.3/Vbeta8.2 mice. Thus, activated Th1 cells in the periphery of Valpha2.3/Vbeta8.2 mice may traffic to the CNS in response to CC chemokines, influencing sEAE.     

Noonan's and DiGeorge syndromes with monosomy 22q11

A boy with the dysmorphic features of Noonan's syndrome and pulmonary valve stenosis who had evidence of hypoparathyroidism and abnormal T lymphocyte numbers in the neonatal period is reported. He had a normal karyotype but molecular analysis revealed a submicroscopic deletion within chromosome 22q11, the region deleted in DiGeorge syndrome. Thus this child has both Noonan's syndrome and DiGeorge syndrome; 22q11 is a candidate region for a gene defective in Noonan's syndrome.     

Comparison of auditory steady-state response and auditory brainstem response thresholds in children

Recently, auditory steady-state responses (ASSRs) have been proposed as an alternative to the auditory brainstem response (ABR) for threshold estimation. The goal of this study was to investigate the degree to which ASSR thresholds correlate with ABR thresholds for a group of sedated children with a range of hearing losses. Thirty-two children from the University of Iowa Hospitals and Clinics ranging in age from 2 months to 3 years and presenting with a range of ABR thresholds participated. Strong correlations were found between the 2000-Hz ASSR thresholds and click ABR thresholds (r = .96), the average of the 2000- and 4000-Hz ASSR thresholds and click ABR thresholds (r = .97), and the 500-Hz ASSR and 500-Hz toneburst ABR thresholds (r = .86). Additionally, it was possible to measure ASSR thresholds for several children with hearing loss that was great enough to result in no ABR at the limits of the equipment. The results of this study indicate that the ASSR may provide a reasonable alternative to the ABR for estimating audiometric thresholds in very young children.     

Effect of exogenous surfactant on total respiratory system compliance

We measured total respiratory system compliance (Crs) before and after instilling 25 mg artificial surfactant in 1 ml saline down the endotracheal tube of preterm babies requiring resuscitation at birth, and compared results with data from 6 similar babies receiving saline only. Surfactant did not produce a significant improvement in Crs.     

Percutaneous gastrostomy for enteral feeding

Over a period of 18 months, percutaneous nonendoscopic gastrostomy using the Seldinger technique was successfully performed in 32 adults for enteral feeding. There were no deaths or major morbidity related to the procedure. Three patients died of existing disease within 30 days; one had peritoneal irritation following dislodgement of the catheter two days after the procedure but responded to conservative treatment with antibiotics alone. The authors conclude that this procedure is simple and safe and represents the preferred method of gastrostomy for enteral feeding.     

Common accreditation and educational problems in obstetrics-gynecology residencies

The Accreditation Council for Graduate Medical Education (ACGME) accredits U.S. institutions that offer graduate medical education, including that in obstetrics and gynecology. The ACGME's 23 Residency Review Committees (RRCs) monitor these programs. The RRC for obstetrics and gynecology has identified 18 common problems in obstetrics-gynecology residency programs. Upon identifying one or more of these problems in an obstetrics-gynecology residency program, the RRC can withdraw accreditation or grant probation or continued probation.