Delineation of T-progenitor cell activity within the CD34+ compartment of adult bone marrow

T-cell production is largely dependent on the presence of a thymus gland where CD34+ precursors mature into T lymphocytes. Prethymic stages of T-cell development are less defined. Therefore, this study aims to delineate T-progenitor cell potential within the CD34+ Lineage-- (Lin-) cell compartment of adult bone marrow (ABM). Fractionation of CD34+ Lin- ABM cells with CD45RA, Thy-1, CD38, and HLA-DR failed to absolutely segregate T-cell reconstituting ability, indicating broad distribution of T-progenitor cell potential. Titration experiments showed that low numbers of CD34+ Lin- CD45RA+ (RA+) cells had greater thymus repopulating ability than CD34+ Lin- CD45RA- cells (RA-). The great majority (> 95%) of RA+ cells expressed CD38, HLA-DR and 70% to 90% of RA+ cells lacked Thy-1 surface expression. RA+ cells contained colony-forming unit granulocyte-macrophage (CFU-GM) progenitor cells but were depleted of erythroid potential, did not provide hematopoietic reconstitution of human bone fragments implanted into SCID mice, and did not efficiently maintain CD34+ cells with secondary clonogenic potential in bone marrow cultures. Thus, RA+ cells are oligopotent (nonprimitive) CD34+ progenitors with T-cell reconstituting ability. In contrast, these same assays indicated that CD34+ Lin- CD45RA- cells (RA- cells) comprised hematopoietic stem cells (HSC) with primitive multilineage (T, B, myeloid, and erythroid) hematopoietic potential. It was confirmed that HSC-containing populations, such as CD34+ Lin- CD45RA- Thy-1+ cells had thymus repopulating ability. Culture of RA- cells on murine bone marrow stromal cells in the presence of interleukin (IL)-3, IL-6, and leukemia inhibitory factor (LIF) generated CD34+ CD45RA+ progeny engrafting in a secondary severe combined immunodeficiency (SCID)-hu thymus assay. Altogether, our results underscore the fact that T-cell reconstituting potential can be dissociated from HSC activity. Furthermore, we speculate that HSC might develop into the T lineage indirectly, via differentiation into an intermediate oligopotent CD34+ CD45RA+ stage. Finally, T-progenitor cells can be cultured in vitro.     

Detection of hepatitis C virus natural recombinant RF1_2k/1b strain among intravenous drug users in Uzbekistan

Aim:  A series of recent studies have indicated the presence of natural intergenotypic recombinant hepatitis C virus (HCV) strains in distinct parts of the world. The majority of the current genotyping methods are based on analysis of either 5'UTR, structural (Core/E1/E2) or non-structural (NS5B) genomic regions of the virus.
Methods:  In the present study, based on both structural and non-structural regions, we determined the genotype of 55 anti-HCV-positive intravenous drug users (IDUs) in Uzbekistan.
Results:  HCV-3a (67.3%) was the most prevalent genotype in this cohort, followed by HCV-1b (27.3%). A discrepancy in results was observed between structural and non-structural regions in one case (1.8%). Phylogenetically this strain was related to the previously reported RF1_2k/1b variant. Based on accumulated sequences, specific primers were designed for polymerase chain reaction (PCR) spanning the tentative intergenotypic crossover point of RF1_2k/1b. The sensitivity and specificity of the method were assessed using generated template clones of HCV-1b, 2a, 2 k and RF1_2k/1b. The method was applied to 55 cases in the present study and only one case showed a positive result, indicating that in these individuals, the variant is not present as a minor quasispecies clone.
Conclusion:  In conclusion, the finding of RF1_2k/1b in Central Asia indicates that the variant has wide geographic distribution. The PCR-based screening method developed in this study should be useful in further epidemiological and clinical studies on the recombination phenomenon in HCV.     

The validity and responsiveness of generic utility measures in rheumatoid arthritis: a review

OBJECTIVE: Cost-utility analysis is increasingly important as healthcare providers aim to invest scarce resources in interventions offering the greatest health benefit. The ability to attach utility values to health states is essential, and is increasingly performed using generic scales. However, the evidence regarding the validity of generic utility scales in rheumatoid arthritis (RA) is unclear. We summarize and review evidence on the validity and comparative performance of generic utility scales in RA. METHODS: We searched the English-language medical literature for studies using utilities in RA between 1980 and mid-2006. Reports describing primary evidence of the validity or performance of a generic utility scale in RA were selected, summarized, and reviewed using the OMERACT filter. RESULTS: In total 923 articles were identified, of which 228 reported the use of utility scales in RA; 26 studies related to the validation or evidence of generic utility scales in RA, the EQ-5D, Health Utility Index-2 (HUI2) and HUI3, SF-6D, and Quality of Well-Being Scale. The EQ-5D, HUI2 and HUI3, and SF-6D all have consistent evidence of construct validity and responsiveness in RA, but each has limitations. CONCLUSION:The EQ-5D and HUI3 have been the most extensively studied instruments and show validity and responsiveness for use in RA, but both instruments have limitations. The SF-6D is relatively new and appears to have potential for use in milder RA, but needs further evaluation. More longitudinal head-to-head evaluation of measures is needed across the spectrum of RA disease severity to further investigate their comparative properties, and to seek consensus on the best utility measure for use in economic evaluation.     

Immunosupportive therapies in aging

The primary role of the immune system is to protect the organism against pathogens, but age-associated alterations to immunity increase the susceptibility of the elderly to infectious disease. The exact nature of these changes is still controversial, but the use of screening procedures, such as the SENIEUR protocol to exclude underlying illness, helped to better characterize the changes actually related to physiological aging rather than pathology. It is generally agreed that the most marked changes occur in the cellular immune response reflecting profound alterations in T cells. Much of this is due to thymic involution as well as changes in the proportions of T cell subpopulations resulting from antigen exposure, and altered T cell activation pathways. However, a body of data indicates that innate immune responses, including the critical bridge between innate and adaptive immunity, and antigen presenting capacity are not completely resistant to senescence processes. The consequences of all these alterations are an increased incidence of infections, as well as possibly cancers, autoimmune disorders, and chronic inflammatory diseases. The leading question is what, if anything, can we do to prevent these deleterious changes without dangerously dysregulating the precarious balance of productive immunity versus immunopathology? There are many potential new therapeutic means now available to modulate immunosenescence and many others are expected to be available shortly. One main problem in applying these experimental therapies is ethical: there is a common feeling that as ageing is not a disease; the elderly are not sick and therefore do not require adventurous therapies with unpredictable side-effects in mostly frail individuals. Animal models are not helpful in this context. In this chapter we will first briefly review what we think we know about human immunosenescence and its consequences for the health status of elderly individuals. We will then discuss possible interventions that might one day become applicable in an appropriate ethical environment.     

克隆人血小板源性生长因子B基因构建腺相关病毒载体及其病毒滴度测定

目的:克隆人血小板源性生长因子B基因于腺相关病毒载体中,以获得高感染滴度的重组人血小板源性生长因子B基因腺相关病毒。方法:实验于2005-10/2006-11在青岛大学医学院附属医院中心实验室完成。①健康足月产妇胎盘组织由青岛大学医学院附属医院妇产科提供,产妇及其家属均知情同意。DH5α宿主菌由青岛大学医学院附属医院中心实验室制备保存。②Trizol试剂提取健康足月产妇胎盘组织总RNA,反转录-聚合酶链反应一步法克隆人血小板源性生长因子B基因全长开放读框。聚合酶链反应产物定向克隆于腺相关病毒载体,重组人血小板源性生长因子B基因腺相关病毒载体进行双酶切和测序鉴定。③采用磷酸钙转染法将重组人血小板源性生长因子B基因腺相关病毒载体、腺相关病毒包装载体,腺相关病毒辅助载体共转染腺相关病毒293细胞,包装得到重组腺相关病毒并回收病毒原液,显微镜下观察细胞及培养基的变化。④以携带β-半乳糖苷酶基因的腺相关病毒作为报告基因同重组人血小板源性生长因子B基因腺相关病毒载体一样共转染相关病毒293细胞,对报告基因行X-Gal染色,通过蓝染的细胞计算病毒滴度。结果:①重组人血小板源性生长因子B基因腺相关病毒载体酶切鉴定及序列分析:聚合酶链反应产物经电泳证明大小正确,重组人血小板源性生长因子B基因腺相关病毒载体酶经双酶切和测序鉴定证实将血小板源性生长因子B基因正确插入。②腺相关病毒293细胞转染过程中病毒颗粒的产生:腺相关病毒293细胞转染6h后培养基底部出现无数小黑色颗粒,为加入的转染复合物颗粒。24h后腺相关病毒293细胞部分变圆,随着病毒增殖,细胞成串浮起,出现细胞病理效应。48h后细胞变形,逐渐从壁上脱落。72h后培养基的颜色从红色变化为橙色或黄色。③病毒滴度检测:通过携带β-半乳糖苷酶基因的腺相关病毒感染细胞后X-gal染色计数,测定重组腺相关病毒滴度为1×1010 L-1。结论:成功构建表达人血小板源性生长因子B基因的重组腺相关病毒载体,为进一步研究血小板源性生长因子B基因治疗角膜病和相关细胞系与组织的增殖提供实验基础。     

Lichen planus pemphigoides: four new cases and a review of the literature

Lichen planus pemphigoides (LPP) is a rare autoimmune blistering disease. It appears to be combination of lichen planus and bullous pemphigoid. We describe four new cases of LPP and discuss the epidemiological, clinical, pathological, and therapeutic features of this singular association through a review of the 74 published cases within the English literature. We report four cases of LPP (three women aged respectively 47, 51, and 53 years old, and a 53‐year‐old man). All patients presented with bullae on lichenoid and normal skin, predominately on the extremities. The diagnosis was confirmed by immunohistological findings. Our patients were treated with oral corticosteroids with a good response. Our review of the literature of 78 cases of LPP (65 adults and 13 children) showed that it involved adults (mean age: 54 years), with a slight female preponderance. A mean lag time between LP and the development of LPP was 8.3 months. LPP is characterized by developing blisters on lichenoid lesions and on uninvolved skin with more acral distribution of bullous lesions. Involvement of palms and soles was more frequent in children. The diagnosis is based on pathological and immunological confrontation. LPP is usually idiopathic, but some cases were reported in association with various drugs. There have also been reports of association with internal malignancy. Most cases of LPP are successfully treated with systemic corticosteroids. In most cases, the prognosis was good.     

Laryngeal mask airway for ventilation during diagnostic and interventional fibreoptic bronchoscopy in children

BACKGROUND: The use of the flexible fibreoptic bronchoscope in infants and children has expanded to include both interventional and diagnostic bronchoscopy. The present report utilizes the laryngeal mask airway (LMATM) for ventilation and anaesthesia administration in children during fibreoptic bronchoscopy using an adult bronchoscope. METHODS: The technique was used in 10 children; their age ranged between 1.2 and 5 years. Six of these children had a history of foreign body aspiration and underwent interventional bronchoscopy, while four children underwent diagnostic bronchoscopy. Anaesthesia was induced by facemask using sevoflurane 6-8% followed by the insertion of a LMA size 2 or 2.5. A swivel adapter connected the proximal end of the LMA to the T-piece anaesthesia system. Anaesthesia was then maintained with spontaneous breathing of sevoflurane 2-4% in oxygen, delivered via the LMA. A flexible adult fibreoptic bronchoscope (outer diameter 4.9 mm) was inserted via the swivel adapter. RESULTS: The procedure could be accomplished successfully in the 10 patients. However, one child developed laryngospasm that was easily relieved by deepening the level of anaesthesia. In a second child hypoxia and hypercarbia occurred and were relieved by intermittent withdrawal of the fibreoptic bronchoscope. CONCLUSIONS: Laryngeal mask airway is a safe and effective adjunct to fibreoptic bronchoscopy under general anaesthesia in children. Its larger internal diameter compared with a tracheal tube permits the use of relatively large fibreoptic bronchoscope without a significant increase in airway resistance.     

Acute kidney injury in critically ill A(H1N1)-infected patients: a study of the prognoses

Purpose: to identify factors correlated with poor outcome and factors correlated with acute kidney injury (AKI) onset in critically A(H1N1) infected patients. Methods: All patients admitted for respiratory distress due to a confirmed infection by A(H1N1) virus were included retrospectively. Results: Thirty‐four patients were included. Mean age was 37.3 ± 20.8 years. Independent factors correlated to mortality in multivariate analysis were shock [OR = 32.52, CI95% (1.29–816.3); p = 0.034], AKI [OR = 31.12, CI95% (1.3–746.5); p = 0.034] and hyperglycaemia over than 5.7 mmol/l on admission [OR = 74, CI95% (1.01–5495); p = 0.049]. Only age over 30 years was identified as an independent factor correlated with the onset of AKI [OR = 18, CI95% (1.04‐312.41); p = 0.047] in multivariate analysis. Conclusion: AKI, as well as hypotension, is an independent factor correlated with mortality. Its onset is usually linked to multi‐organ failure. Advanced age is an important risk factor for renal dysfunction in this group of patients.     

Successful treatment of refractory Hodgkin's disease by high-dose combination chemotherapy and autologous bone marrow transplantation

Forty-four patients with refractory Hodgkin's disease were treated with high-dose combination chemotherapy followed by autologous bone marrow rescue. Twenty-two patients (50%) entered complete remission within 6 months of the procedure and four other patients are free of disease progression. Only two patients have subsequently relapsed from complete remission (CR). Bone marrow suppression was the predictable major toxicity of this procedure, and two patients (4.5%) died of sepsis during the aplastic phase. High-dose therapy with autologous bone marrow transplantation (ABMT) appears to be an effective salvage regimen for patients with refractory Hodgkin's disease.