特殊部位硬膜下血肿的CT、MRI诊断

目的 分析大脑镰、小脑幕硬膜下血肿的CT、MRI表现，提高其诊断准确率。方法 回顾性分析总结60例大脑镰、小脑幕硬膜下血肿的CT和MRI资料。结果 60例中发生于单侧55例，双侧5例；大脑镰硬膜下血肿25例表现为条索状，10例呈小带状，发生于两侧4例，MRI表现为双轨征，小脑幕下血肿7例呈片状，5例呈扇形，MRI表现为片带状高信号影，小脑幕并大脑镰硬膜下血肿6例呈“Y”形，3例呈镰刀状。结论 通过60例大脑镰、小脑幕硬膜下血肿的CT、MRI表现的比较分析，得到了进一步的认识，有助于提高诊断符合率，MRI在定位诊断方面优于CT。     

Expression of natural killer receptor alleles at different Ly49 loci occurs independently and is regulated by major histocompatibility complex class I molecules

Ly49 receptor genes are expressed by subsets of natural killer (NK) cells in an overlapping fashion, accounting for the capacity of NK subsets to attack host cells that have selectively downregulated self-major histocompatibility complex (MHC) class I molecules. It was shown previously that most NK cells express only one or the other allele of a given Ly49 gene, while a smaller population expresses both alleles. However, the methods used to detect monoallelic and biallelic cells were nonquantitative. Here, new allele-specific antibodies were used to provide the first quantitative examination of biallelic and monoallelic expression of Ly49A and Ly49G2. The results demonstrate conclusively that most Ly49A(+) and Ly49G2(+) NK cells express the corresponding gene in a monoallelic fashion, with a smaller subset expressing both alleles. Unexpectedly, biallelic Ly49A(+) NK cells were more numerous than predicted by completely independent allelic expression, suggesting some heterogeneity among NK progenitors in the potential to express a given Ly49 gene. The data also show that cells expressing one allele of Ly49G2 may express Ly49A from the same or opposite chromosome with equal likelihood, indicating that the expressed allele is chosen independently for different Ly49 genes. Finally, the data demonstrate that biallelic expression of Ly49A or Ly49G2 occurs least frequently in mice that express ligands for these receptors (H-2(d) mice), and most frequently in class I-deficient mice. Thus, biallelic expression of Ly49 genes is regulated by interactions of NK cell progenitors with MHC class I molecules.     

Identification of 14 new alleles at the fucosyltransferase 1, 2, and 3 loci in Styrian blood donors, Austria

BACKGROUND: Genes for fucosyltransferases 1 (FUT1:H), 2 (FUT2:Secretor), and 3 (FUT3:Lewis) encode enzymes crucial for ABH and Lewis blood group antigen synthesis. They are highly polymorphic and ethnically and geographically specific.
STUDY DESIGN AND METHODS: Genetic variations and allele frequencies of FUT1, FUT2, and FUT3 encoding regions and flanking sequences were analyzed in 100 Styrian blood donors by systematic sequencing. Haplotypes were verified with sequence-specific primers. To identify discrepancies, serologically determined ABO and Lewis blood groups were correlated to respective genotypes.
RESULTS: Two novel FUT1 alleles were defined by 9C>T (silent) and 991C>A (P331T) mutations, the latter located in the catalytic domain of the enzyme. Five new alleles of FUT2 were found: three were characterized by new variants and two resulted from new combinations of known polymorphisms. The new 412G>A (G138S) mutation also is located in the catalytic domain. A new nonsecretor allele, based on the presence of 428G>A (nonsense), was found. Another FUT2 allele may have resulted from an intragenic crossover event. FUT3 analysis revealed seven novel alleles, partly based on the new mutations 41G>A (R14H), 1060C>G (R354G), 735G>C (silent), and 882C>T (silent). While 41G>A is placed in the cytoplasmic domain and functional, 1060C>G is placed in the catalytic domain.
CONCLUSION: Multiple common and sporadic sequence variations including 14 new alleles at FUT1, FUT2, and FUT3 loci were identified. Four novel mutations result in amino acid substitution in the protein. Three of them are predicted to have adverse effects on the enzyme activity. A novel nonsecretor allele was found.     

Identification of six new alleles at the FUT1 and FUT2 loci in ethnically diverse individuals with Bombay and Para-Bombay phenotypes

BACKGROUND: The Bombay and para-Bombay phenotypes arise from mutations of the FUT1 gene that silence the gene or affect the efficiency of the encoded 2-alpha-fucosyltransferase. Samples from seven individuals of different geographic backgrounds whose red blood cells had an apparent Bombay or para-Bombay phenotype were investigated. Among these, novel FUT1 and FUT2 alleles were identified. STUDY DESIGN AND METHODS: Standard serologic techniques were used. Genomic DNA was sequenced with primers that amplified the coding sequence of FUT1 and the related secretor gene, FUT2. Routine ABO genotyping analysis was performed. RESULTS: Five new FUT1 alleles were identified that silenced FUT1 or weakened alpha2FucT1 activity. These were 35C>T, 269G>T (Ala11Val, Gly89Val); 421A>G (Trp140Stop); 538C>T, 1089T>G (Gln180Stop, Ala363Ala); 689A>C (Gln230Pro); and 917C>T (Thr305Ile). In addition, both homozygosity and heterozygosity for the previously reported mutation, 826C>T (Gln276Stop), were observed. Four of seven samples were homozygous for the silencing mutation 428A in FUT2. One new FUT2 allele was identified: 278C>T, 357C>T (Ala93Val, Asn119Asn). CONCLUSIONS: These results add to the growing database of apparently sporadic and random mutations in the FUT1 gene and confirm previous reports regarding the lack of ethnic bias. In contrast, our data reinforce the apparent maintenance of the common nonsecretor FUT2 alleles in the population.     

Anti-tumor vaccination in heterozygous congenic F1 mice: presentation of tumor-associated antigen by the two parental class I alleles

Peptide vaccination of homozygous mice against syngeneic tumors using single major histocompatibility complex (MHC) class I-restricted cytotoxic T lymphocyte (CTL) epitopes elicits effective immune responses against metastatic growth. So far, single-peptide vaccination of patients against their autologous tumors seems to elicit less satisfactory results. In this study, the authors tried to determine whether effective anti-metastatic immunity requires the presentation of peptides restricted by the two parental class I major histocompatibility complex alleles in heterozygous hosts. The immune response against the H-2b-derived 3LL Lewis lung carcinoma was evaluated in heterozygous recombinant congenic F1 mice (Kk x K(b)) and (Kd x K(b)). Vaccination of such heterozygous animals with dendritic cells expressing the two parental H-2K alleles, pulsed with total tumor extract, elicited a potent anti-metastatic response. A comparable response was obtained after vaccination with tumor cells genetically modified to express the two class I alleles. In contrast, vaccination of the heterozygous mice with dendritic cells expressing only one of the parental F1 H-2K alleles or with tumors expressing only one H-2K allele failed to elicit effective immunity against tumor metastasis in recombinant congenic F1 mice. It appears, therefore, that to achieve effective anti-metastatic immunotherapy in heterozygous organisms, presentation of cytotoxic T lymphocyte epitopes restricted by the two parental class I alleles is required.     

Enrichment of mutant alleles by chromatographic removal of wild type alleles: a new principle for the detection of alleles with unknown point mutations at excess of wild type alleles.

In human carcinomas, mutations that alter tumour genes such as the KRAS, P53, or APC genes, are mostly point mutations. The detection of mutant alleles of tumour genes in specimens such as urine, pancreatic juice, sputum, and stool holds great promise for an early diagnosis of cancer. In addition, the detection of mutant tumour genes in tissue samples, such as lymph nodes or resection margins, may allow a sensitive diagnosis of residual malignant disease. However, the reliable detection of mutant alleles in excess of wild type alleles remains an unresolved analytical problem when the mutations are not known a priori. In the present communication, a new approach is described which makes possible the detection of unknown point mutations in tumour genes at excess of wild type alleles. The method is based on the removal of wild type alleles by hybridisation to immobilised complementary oligonucleotides. Using this approach, an enrichment of mutant KRAS, P53 and APC alleles of one mutant in up to 10(3) normal alleles has been achieved. Parallel miniaturised separation units with oligonucleotides complementary to defined sequences of a wild type allele should allow the detection of unknown point mutations as well as small insertions or deletions which occur in the sequence range covered by the oligonucleotides.     

少儿强直性脊柱炎与幼儿类风湿性关节炎HLA-B27亚型的鉴别诊断

背景少儿强直性脊柱炎( juvenile ankylosing spondylitis, JAS)和幼儿类风湿关节炎( juvenile rheumatoid arthritis, JRA)与 HLA-B27抗原关联研究已近 25年历史,国外有学者报道强直性脊柱炎( ankylosing spondylitis, AS)和关节炎与 HLA-B27等位基因亚型关联不同. 目的探讨 HLA-B27等位基因亚型与 JAS和 JRA的关联性及其在发病机制中的作用 ,以期能够找到早期诊断 JAS检测方法. 设计非随机对照的实验研究. 地点、对象和方法纳入 60 例北京儿童医院住院及门诊的 JAS和 JRA患者, 5个家系中患者的父亲或母亲 5例及 9例正常个体(来源于 200多例健康自愿骨髓移植供者).用 PCR/SSP方法对 74例 HLA-B27等位基因亚型进行研究 ,并进行关联分析. 主要观察指标 JAS和 JRA与 HLA-B27等位基因亚型相关性分析; HLA-B* 2704等位基因在 JAS和 JRA中的差异 ;家系资料 ;单倍型分析 ;纯合子分析.表明 HLA-B* 2704与 C* 1202连锁紧密而与 HLA-A连锁不紧密, JAS有明显家族遗传倾向. 结果 本组人群的 HLA-B27等位基因由 HLA-B* 2704,* 2705,* 2702,* 2707 4种亚型组成 ,其中 JAS患者 HLA-B27等位基因亚型频率 B* 2704为 56.25% ;B* 2705为 40.63% ;B* 2702为 3.13% ;JRA HLA-B27等位基因亚型频率为 B* 2705为 60.7% ;B* 2704为 28.57%; B* 2702为 3.57% 及 B* 2707为 7.14% ;JAS与 JRA结果比较 , HLA-B* 2704基因频率在 JAS组高于 JRA组 (RR=3.21,P< 0.05). 结论JAS与 HLA-B* 2704等位基因亚型关联.对 HLA-B27等位基因亚型的检测 ,可成为 JAS和 JRA鉴别诊断中一个有价值实验指标.     

Bone in the pregnant mother and newborn at birth

BACKGROUND: Changes in maternal bone during pregnancy may affect fetal bone mineralization. ISSUES: The biphasic changes in maternal bone histology (temporary loss of cancellous bone in early pregnancy restored by term gestation) are consistent with corresponding blood biochemistry changes; increased bone resorption markers in the first trimester, while bone formation markers increased in the last trimester. Postpartum bone mineral density (BMD) by DEXA is increased at cortical bone and decreased at trabecular bone sites compared with prepregnancy values. The mean reduction of spine BMD is 3.5% from prepregnancy to immediate postpartum. Neonatal bone mineral content (BMC) is different by season of birth, low weight relative to gestation, and having a diabetic mother. Lower total body BMC and high bone resorption marker in winter vs. summer-born newborns was related to low vitamin D, indicating alterations of fetal bone metabolism by maternal D deficiency. Lower BMC and decreased bone formation marker in infants born small for gestational age than those born appropriate for gestation may relate to reduced transplacental mineral transfer. Low BMC in infants of diabetic mother was correlated inversely with poor control of maternal diabetes during early pregnancy. CONCLUSIONS: During pregnancy, maternal bone mineral metabolism are changed, and influences on fetal bone mineralization occur in utero.     

Single and double incompatibility at vWA and D8S1179/D21S11 loci between mother and child: implications in kinship analysis

BACKGROUND: Two cases of paternity dispute, examined with 17 autosomal short tandem repeats signified a possible single and double maternal mismatch at vWA and D8S1179/D21S11 loci in the children under investigation. METHODS: Seventeen autosomal STR loci were analyzed using AmpFlSTR Identifiler, PowerPlex 16 kits. Six STR markers on X chromosome were amplified and analyzed. Mutated alleles were amplified, cloned in pCR(R)II-Topo vector, sequenced and investigated. RESULTS: In case S1 the vWA locus indicated an allele mismatch with the mother. All the vWA alleles on amplification, cloning and sequencing depicted an increase of 2 repeats in the child. In case D1 maternal child inconsistency at D8S1179 and D21S11 loci was observed. The alleles were amplified, cloned and sequenced to analyze the repeat structure. Increase of 1 repeat in D8S1179 locus and an insertion mutation in D21S11 locus between the mother and questioned child were confirmed. A complete match with the 17 autosomal loci of the father and 6 X chromosome STR loci of the mother was observed in both the cases. CONCLUSION: This is the first report of a maternally transmitted single mismatch at vWA locus and double mismatch at D8S1179 and D21S11 loci due to increase/mutation of the repeat in the paternity DNA testing. The results of nucleotide sequencing and STR analyses convincingly established that the suspected father and the mother are undeniably the biological parents of the questioned child.     

Mitral valve prolapse: comparison of diagnosis by physical examination and echocardiography

To determine how well physical examination findings suggestive of mitral valve prolapse (MVP) correlate with echocardiographic evidence of MVP, we retrospectively reviewed the charts of 104 patients referred to an Air Force Cardiology Clinic for echocardiography to rule out MVP. In each case, the referring physician's specialty and his findings on cardiac physical examination were recorded. All patients had M-mode echocardiography, and half of the patients had two-dimensional echocardiography. Sensitivities, specificities, and likelihood ratios for the physical examination were calculated using echocardiography as the comparison standard. The combination of a systolic click and a systolic murmur was the physical examination finding most predictive of echocardiographic MVP, with a positive likelihood ratio of 2.43. Other combinations of physical findings yielded likelihood ratios close to 1. No differences were found based on the specialty of the examining physician. We conclude that when practicing physicians find a systolic click and murmur, MVP is likely to be present on echocardiography, though one third of the patients will have normal echocardiograms. Other combinations of physical findings are of little help in predicting echocardiographic MVP.     

袋鼠式护理国内外研究现状

介绍了国外袋鼠式护理研究现状、国内袋鼠式护理研究状况、国内研究存在的不足,在找出差距及分析原因的基础上,为袋鼠式护理在国内的合理应用提出建议。     

Resistance alleles at two non-major histocompatibility complex-linked insulin-dependent diabetes loci on chromosome 3, Idd3 and Idd10, protect nonobese diabetic mice from diabetes

Development of diabetes in NOD mice is polygenic and dependent on both major histocompatibility complex (MHC)-linked and non-MHC-linked insulin-dependent diabetes (Idd) genes. In (F1 x NOD) backcross analyses using the B10.H-2g7 or B6.PL-Thy1a strains as the outcross partner, we previously identified several non-MHC Idd loci, including two located on chromosome 3 (Idd3 and Idd10). In the current study, we report that protection from diabetes is observed in NOD congenic strains having B6.PL-Thy1a- or B10-derived alleles at Idd3 or Idd10. It is important to note that only partial protection is provided by two doses of the resistance allele at either Idd3 or Idd10. However, nearly complete protection from diabetes is achieved when resistance alleles are expressed at both loci. Development of these congenic strains has allowed Idd3 to be localized between Glut2 and D3Mit6, close to the Il2 locus.