Molecular evidence that in situ-transduced fetal liver hematopoietic stem/progenitor cells give rise to medullary hematopoiesis in adult rats

We exploited the ability to transduce fetal liver hematopoietic stem/progenitor cells in situ with recombinant retrovirus, together with the ability to analyze proviral integration patterns into chromosomal DNA, to detect the cellular and organ fate of hematopoietic stem and progenitor-derived progeny in tissues and in the circulation of neonatal and adult rats. Two hundred seventeen fetuses were injected with retrovirus supernatant on day 16 of gestation, before the development of the bone marrow cavity. The progeny of 41 stem and progenitor cells from 97 liveborn rats were clonally identified. Pluripotent and lineage-restricted stem/progenitor clones derived from the fetal liver consistently gave rise to progeny in the marrow of newborn and adult rats. Patterns of differentiation of transduced stem and progenitor cells fell into distinct subsets. Blood cells derived from in situ transduced cells that originated in the fetal liver circulated throughout the life span of the adult animals. These data provide molecular evidence of the origin of medullary cavity hematopoiesis by cells derived from the fetal liver that were transduced in vivo, homed to the developing medullary cavity and proliferated in a normal medullary hematopoietic microenvironment.     

An 11 base pair duplication in exon 6 of the SMN gene produces a type I spinal muscular atrophy (SMA) phenotype: further evidence for SMN as the primary SMA-determining gene

The gene for autosomal recessive spinal muscular atrophy (SMA) has been mapped to 5q12 in a region that contains repeated markers and genes. Three cDNAs that detect deletions in SMA patients have been reported. One of these, the survival motor neuron (SMN) cDNA, is encoded by two genes (SMNT and SMNC) which are distinguished by base changes in exons 7 and 8. Exon 7 of the SMNT gene is not detectable in approximately 95% of SMA cases, due either to deletion or sequence conversion. There is limited information on the mutations in SMA patients that have detectable SMNT, these are critical for confirmation of SMNT as the SMA gene. Using SSCP analysis of the SMN exons we screened our SMA patients that possess at least one intact SMNT allele for mutations in SMNT. We identified one type I SMA patient with an 11 bp duplication in exon 6 which causes a frameshift and premature termination of the deduced SMNT protein. Dosage and SSCP analysis of SMNT in this family indicated that the father contributed a SMNT-deleted allele to the affected child whereas the mother passed on the 11 bp exon 6 duplication SMNT allele. Analysis of RNA by RT-PCR conclusively demonstrated that the 11 bp duplication is associated with the SMNT locus and not SMNC. This mutation provides strong support for SMN as the SMA-determining gene and indicates that disruption of SMNT on its own is sufficient to produce a severe type I SMA phenotype.      

Improved vessel dilator for percutaneous catheterization

Three commercial vessel dilators and a dilator of an improved design were tested during percutaneous catheterization in 16 mongrel dogs to evaluate arterial damage produced with their use. The results indicate that, although all dilators often produce arterial damage, the improved design produced much less damage. In addition, lesions were less severe overall. The dilator has been safely and successfully used in patients for percutaneous vessel catheterization for the past 30 years at the authors' institution.     

Coil-in-coil technique for vascular embolization

A new technique for vascular embolization using two Gianturco steel coils is described. The authors used a "coil-in-coil" technique to embolize the arteries of 12 dogs. In this technique a large coil is introduced into the artery followed by a smaller coil, which is delivered with a special introducer into the lumen of the first coil. Two coils can therefore be introduced into a shorter length of vessel. This method was as effective as "packing" the vessel with two coils in a row. The coil-in-coil technique is especially advantageous for use in infants and children with short, anomalous vessels, minimizing the risk of coil dislodgment into normal peripheral vessels.     

Vitamin A intake and xerophthalmia among Indian children

OBJECTIVE: To estimate prevalence of xerophthalmia and to assess dietary intake of vitamin A in Indian children aged under 6 y. DESIGN: Cross sectional study. STUDY SETTING: Urban slums under Urban Health Centre affiliated to Department of Preventive and Social Medicine, Government Medical College, Nagpur, India. PARTICIPANTS: The study included 1094 all children under 6 y of age, from two randomly selected urban slums. METHODS: Xerophthalmia was diagnosed on the basis of ocular signs and symptoms (WHO recommendations). Dietary intake of vitamin A was assessed by using one year recall method recommended by International Vitamin A Consultative Group. RESULTS: Prevalence of xerophthalmia was estimated to be 8.7%. Nine hundred and ninety-five (90.9%) study subjects were identified as inhabitants consuming dietary vitamin A at below recommended levels. (UPF score < 210). Five hundred and ninety-three (54.2%) study subjects were consuming dietary vitamin A at approximately less than 200 RE/d (UPF score < 120) while 402 (36.2%) were consuming approximately 200-300 RE/d (UPF score 120-210). The prevalence of xerophthalmia was found to be decreasing as the score of usual pattern of food consumption (UPF) increased. CONCLUSIONS: Children with a dietary intake represented by a UPF score of less than 120 were at high risk of developing xerophthalmia, whereas, those consuming vitamin A equal to a UPF score greater than 120 were at comparatively less risk despite being below the recommended levels.     

Is Gd-DTPA required for routine cranial MR imaging?

Gadopentetate dimeglumine (gadolinium diethylenetriaminepentaacetic acid [DTPA]) was administered prospectively to 500 consecutive children and adults referred for routine cranial magnetic resonance (MR) imaging over a 4-month period. Pre- and postcontrast images were blindly and independently interpreted by two experienced neuroradiologists. Specific criteria were provided to the readers to define objectively when contrast material enhancement (or lack thereof) would be considered "radiologically helpful." Contrast-enhancing lesions were observed in 99 cases (20%). In only 15 cases (3%) did Gd-DTPA permit detection of lesions not also apparent on the precontrast studies. Contrast enhancement was considered radiologically helpful in 74 of the 99 cases. Lack of enhancement was considered helpful in 112 of the 500 cases (22%). Factors that may indicate increased usefulness of Gd-DTPA include increased patient age, definite lesion seen at computed tomography or precontrast MR imaging, prior craniotomy for tumor, and clinically documented systemic or central nervous system disease. Gd-DTPA should probably be used routinely for cranial MR imaging in most patients, except, perhaps, children and young adults with normal precontrast images.     

婴儿心肺转流20例无死亡的灌注体会

0　引言　1997-03/1998-07,我科曾对70例小于3岁有先心病患儿进行体外循环下心内畸形矫治,其中小于1岁婴儿20例无1例死亡.现将20例婴儿患者的体外循环预充及转流体会总结如下.1　对象和方法1.1　对象　婴儿20(男11,女9)例.年龄2～12mo.3mo3例,4～6mo6例,7～9mo6例,12mo5例.体质量3～7.5(平均5.7)kg.病种包括:室缺10例,室缺合并肺动脉高压4例,室缺合并肺动脉高压和动脉导管未闭2例,法乐三联症1例,法乐四联症3例.1.2　方法　1体外循环预充:血液稀释度为HCT20%,不足部分预充新鲜库血,一般晶体醋酸钠平衡盐250～400mL,血浆100～150mL或200g.L…     

大连理工大学图书馆员的人格因素和职业现状分析

目的:通过对图书馆员的人格因素和职业现状分析,为图书馆的人力资源管理提供参数。方法:于2005-06/08纳入大连理工大学伯川图书馆馆员72人作为人格测试组,男7人,女65人;同时纳入2005-07前在职的全部馆员122人作为职业现状分析组,男26人,女96人。采用国际公认的卡特尔16种人格因素问卷,对人格测试组进行人格测试。问卷从16个相对独立的人格维度对人进行描绘,全套测试题共187题,每题设有a,b,c3种可供选择的答案。将测试结果输入心理测试软件系统,给出粗分和标准分,再运用软件进行数据的统计分析。对职业现状分析组的全体馆员进行了性别,年龄结构,男女馆员在各工作部门的分布,及馆员的学历构成,技术职称和领导职务的担任比例统计分析。观察人格测试组卡特尔16种人格因素问卷人格类型的次元因素和综合个性应用评价分数,并对全体馆员的自然状况列表进行统计分析,分析其职业现状。结果:发放卡特尔16种人格因素问卷72份,回收完整问卷46份,回收率63.9%,有效率100%。最终人格测试组46人进入结果分析,男5人,女41人。职业现状分析组122人,全部进入结果分析。①人格测试组聪慧性、幻想性、自律性均高于全国专业技术人员常模,差异有显著性意义(9.74±1.22;8.88±1.22;13.11±2.36,11.83±1.25;13.89±2.59,12.40±1.47;t=4.780,3.676,3.901,2.783,P<0.001～0.01)。被试馆员怀疑性和紧张性低于全国专业技术人员常模,差异有显著性意义(9.39±2.85,10.56±1.57;9.76±3.72,11.19±1.65;t=-2.783,-2.606,P<0.01,0.05)。②女性图书馆员占总人数的78.7%,男性图书馆员在年龄结构上处于年龄段的两端,在生理上处于成年早期(30.7%)和晚期(38.4%);女性馆员的年龄集中于30～50岁的年龄段(86.3%)。③男馆员在综合办公室、自动化部和技术服务部的人数分布方面占据优势地位(38.4%,11.5%,11.5%);而女性馆员集中于期刊咨询部、文献建设部、流通阅览部和回溯建库等信息服务咨询部门(24%,15.6%,40.6%,4.2%)。④男馆员在获得博士、双学士、学士学位,及本科、中专学历方面的人数比例大于女性馆员,而女性馆员在获得硕士学位及大专和较低学历方面所占的比例大于男性馆员。⑤男性馆员在高级技术职称和馆级领导高端决策层占优势,在初级和较低技术职称中占比例较大;女性馆员在中级技术职称中级领导层上占比例大于男性馆员。结论:图书馆员女性化,而男性馆员在知识结构、职称、高端决策层领导职务的担任和承担高技术性工作方面的整体水平优于女性馆员。更应着重分析女性图书馆员的生理、心理特点,人格因素和职业特征,进行人力资源的优化组合。