Neural progenitor cells lack immunogenicity and resist destruction as allografts

Multipotent, self-renewing stem and progenitor cells isolated from the mammalian central nervous system (CNS) have been shown to survive as allografts following transplantation to sites throughout the neuraxis. However, studies of this type shed little light upon the immunologic properties of the cells themselves, primarily because little is learned about the intrinsic immunogenic properties of a cell when it is grafted into an immune-privileged site. We have therefore investigated the immunogenic and antigenic properties of CNS progenitor cells by grafting them into a conventional (i.e., non-immune-privileged) site, namely, beneath the kidney capsule. Our results indicate that allogeneic CNS progenitor cells survive at least 4 weeks in a conventional site, during which time they neither sensitize their hosts nor express detectable levels of major histocompatibility complex (MHC) class I or II. These in vivo data are in accord with flow cytometric results showing that CNS progenitor cells do not express MHC class I or class II, either at baseline or upon differentiation in 10% serum. Exposure to interferon gamma, however, reversibly upregulates expression of these key transplantation antigens. Together, these results reveal CNS progenitor cells to possess inherent immune privilege. Since CNS progenitor cell allografts were rejected beneath the kidney capsule following specific sensitization of the host, CNS progenitor cells were able to display alloantigens, albeit not in an immunogenic form.     

Assessment of the Long-Term Impact of Pancreatoduodenectomy on Health-Related Quality of Life Using the EORTC QLQ-PAN26 Module

Annals of Surgical Oncology - Long-term pancreatoduodenectomy (PD) survivors have previously reported favorable quality of life (QoL). However, there has been a paucity of studies utilizing...     

尿毒症患者急性缺氧状态下血清红细胞生成素浓度的变化

７例尿毒症贫血患者在自发急性缺氧状态下，其血清红细胞生成素（ＥＰＯ）浓度显著提高（平均７倍），且与ＰＯ２呈负相关。缺氧状态纠正后血清ＥＰＯ浓度下降。提示尿毒症贫血患者的ＥＰＯ氧依赖调控系统功能尚存在，但处于不敏感的低调状态。进一步了解其机遇，则可能通过促进内源性ＥＰＯ的生成，有助于悄毒症贫血的治疗。     

The mental health of Asian and Pacific Island elders: implications for research and mental health administration

According to the 1990 census, the highly diverse Asian and Pacific Islander (API) American population has doubled in size from 1980 to 1990, and is now the nation's fastest growing minority group. Several studies have documented this population's comparative underuse of mental health services. A review of recent studies on the mental health of Asian and Pacific Island elders identifies a number of risk factors and protectors. Elder APIs appear to have poorer mental health compared to white counterparts, but not the poorest mental health within their own ethnic group. Within-group differences emerge, with recent immigrant groups and colonized populations appearing as most at-risk for mental health problems. A critical variable on this population's mental health status appears to be socioeconomic status,and yet an analysis of other demographic variables, notably nativity and gender, remain contradictory. A research agenda is proposed and implications for mental health administrators are suggested.     

Jasmine green tea epicatechins are hypolipidemic in hamsters (Mesocricetus auratus) fed a high fat diet.

These studies were designed to test the hypolipidemic activity of green tea epicatechins (GTE) isolated from jasmine green tea. In Experiment 1, three groups of hamsters were given a semisynthetic diet containing 200 g lard/kg and 1 g cholesterol/kg for 4 wk. The control group received distilled water, and the other two groups received either 15 g/L green tea water extract (GTWE) or 5.0 g/L GTE solution. Both the GTWE and GTE groups had lower concentrations of serum total cholesterol (TC) and triacylglycerols (TG) than the controls (P < 0.05). In Experiment 2, four groups of hamsters received tap water as the drinking fluid, but they were given the same high fat and cholesterol diet supplemented with 0 (control), 1.1, 3.4 or 5.7 g GTE/kg diet. The hypolipidemic effect of jasmine GTE was dose dependent. In Experiment 3, the time-course of changes in serum TC and TG was monitored in hamsters given the high fat diet supplemented with 5.7 g GTE/kg in comparison with that of controls. The hypolipidemic effects of dietary GTE were evident after feeding for 2 wk. Dietary supplementation of GTE did not affect liver fatty acid synthase. However, GTE-supplemented hamsters had higher fecal excretions of total fatty acids, neutral sterols and acidic sterols compared with the control group. In Experiment 4, hamsters were fed nonpurified diet; the control group drank distilled water, and the GTE group drank distilled water containing 5.0 g GTE/L. No differences in activities of 3-hydroxy-3-methyl glutaryl coenzyme A reductase and intestinal acyl CoA:cholesterol acyltransferase were observed. This study suggests that the hypolipidemic activity of GTE is not due to inhibition of synthesis of cholesterol or fatty acid but is most likely mediated by its influence on absorption of dietary fat and cholesterol.     

Prediction of perinatal outcome in fetuses suspected to have intrauterine growth restriction: Doppler US study of fetal cerebral, renal, and umbilical arteries

PURPOSE: To determine and compare the diagnostic performance of fetal middle cerebral (MCA), renal (RA), and umbilical (UA) arterial Doppler ultrasonography (US) for prediction of adverse perinatal outcome in suspected intrauterine growth restriction (IUGR). MATERIALS AND METHODS: Two hundred ninety-three small-for-gestational age fetuses (24-39 weeks at recruitment and US-estimated weight or abdominal circumference below 10th percentile) were prospectively examined with Doppler US of the UA, MCA, and RA. Clinicians were blinded to MCA and RA Doppler measurements. RESULTS: Seventy-six fetuses (25.9%) had at least one major or minor adverse perinatal outcome. Major outcomes included stillbirth, neonatal death, neurologic complication, and necrotizing enterocolitis. The MCA pulsatility index (PI), compared with the UA PI and RA PI, was more sensitive (72.4% vs 44.7% and 8.3%) but less specific (58.1% vs 86.6% and 92.6%) in predicting adverse outcome. The UA PI had the highest positive likelihood ratio (ratio, 3.3); the MCA PI had the lowest negative likelihood ratio (ratio, 0.48). When gestational age at the first Doppler US examination was less than 32 weeks, the MCA PI had a sensitivity of 95.5% and negative predictive value of 97.7% for major adverse outcome (negative likelihood ratio, 0.10). CONCLUSION: In suspected IUGR, while an abnormal UA PI is a better predictor of adverse perinatal outcome than an abnormal MCA or RA PI, a normal MCA PI may help to identify fetuses without major adverse perinatal outcome, especially before 32 weeks gestational age.     

Radiographic verification of pedicle screw pilot hole placement using Kirshner wires versus beaded wires

STUDY DESIGN: Kappa statistics were used to compare the accuracy of two different techniques for verifying pedicle screw pilot hole placement in cadaveric vertebrae. OBJECTIVE: To determine whether clinicians radiographically detect misplaced pedicle screw holes with greater sensitivity and specificity when beaded wires rather than straight Kirschner wires are used. SUMMARY OF BACKGROUND DATA: Pedicle screws commonly are used in orthopedic surgery to obtain and maintain spinal stability. Pedicle screws are reportedly misplaced at a rate of 20% to 40%. Radiographic verification is commonly used to place pedicle screw pilot holes, but this technique is known to be less than 100% accurate. Computer-assisted techniques may allow more accurate screw placement, but these techniques require expensive equipment. METHODS: Pedicle screw pilot holes were drilled into 12 human lumbar and thoracic vertebrae. Some of the holes were misplaced deliberately so that they violated the pedicle walls. Lateral and posteroanterior radiographs of the vertebrae were evaluated by 13 experienced orthopedic spine surgeons and 3 inexperienced observers. At different times, the observers were shown radiographs depicting Kirschner wires or beaded wires placed in the pilot holes. Observers indicated whether they thought the pedicle screw pilot hole violated the pedicle. RESULTS: The sensitivity and specificity of using posteroanterior or lateral radiographs to detect misplaced pedicle screws were increased when beaded wires were placed in the pilot holes. CONCLUSIONS: Radiographic evaluation of beaded wires placed in pedicle screw pilot holes can be both sensitive and specific for misplaced screws. The highest sensitivity and specificity were found using posteroanterior radiographs.     

Osseous free tissue transfer in head and neck reconstruction

Large palatomaxillary and oromandibular defects have a dramatic impact on speech, deglutition, mastication, and cosmesis. Traditional methods of reconstruction, such as locoregional flaps, free bone grafts, alloplastic materials, and prosthetic devices, have difficulty providing meaningful aesthetic and functional reconstruction of these defects. This article discusses current concepts in the reconstruction of large composite palatomaxillary and oromandibular defects with an emphasis on the role of free tissue transfer, including the factors to be evaluated when choosing a method of reconstruction, indications for specific donor sites, and recent technical refinements.