新生儿呼吸机选择的要素

根据新生儿和成人之间呼吸生理的不同，认为新生儿呼吸机与儿童、成人呼吸机无论从那方面来讲都有较大的区别，并从新生儿呼吸生理的特点出发，提出购买新生儿呼吸机时要注意的几个要素。     

急性脑外伤患者脑脊液髓鞘碱性蛋白水平与其损伤类型的关系

目的 探讨急性脑外伤患者脑脊液髓鞘碱性蛋白(CSF-MBP)水平与其损伤类型的关系。 方法 采用放射免疫测定法(RIA)对42例急性脑外伤患者的CSF-MBP进行测定,并测定26例非神经系统疾病患者作对照。结果 严重脑内原发性损伤患者CSF-MBP平均水平显著高于轻中度脑内原发性损伤和单纯颅内血肿者(P<0.01),单纯颅内血肿患者CSF-MBP仅伤后第5天增高;弥漫性脑损伤组CSF-MBP水平显著高于局灶性脑损伤组(P<0.01),伤后1周内持续处于高水平状态。结论 CSF-MBP的测定有助于急性脑外伤患者损伤程度及类型的判定。     

血清IGFBP-3、PDGF及bFGF联合检测对多囊卵巢综合征患者妊娠结局的预测价值

目的 探究血清胰岛素样生长因子结合蛋白-3(IGFBP-3)、血小板来源生长因子（PDGF）及碱性成纤维细胞生长因子（bFGF）联合检测对多囊卵巢综合征（PCOS）患者妊娠结局的预测价值。方法 选取2021年5月—2022年12月在沧州市中心医院接受治疗的150例PCOS孕妇作为PCOS组,另选取同期在该院产检健康的90例孕妇作为对照组。比较两组血清IGFBP-3、PDGF及bFGF水平;根据PCOS组孕妇的妊娠情况分为妊娠结局良好组119例和妊娠结局不良组31例,统计PCOS患者妊娠结局情况并比较血清IGFBP-3、PDGF、bFGF水平;绘制受试者工作特征（ROC）曲线分析血清IGFBP-3、PDGF和bFGF对PCOS的预测价值。结果 PCOS组血清IGFBP-3水平低于对照组（P <0.05）,PDGF、bFGF水平均高于对照组（P <0.05）。妊娠结局不良组血清IGFBP-3水平低于妊娠结局良好组（P <0.05）,PDGF、bFGF水平均高于妊娠结局良好组（P <0.05）。ROC曲线分析结果显示,血清IGFBP-3、PDGF、bFGF水平预测PC...     

Drug Binding to α1-Acid Glycoprotein Studied by Circular Dichroism

The interactions of acidic and basic drugs with ₁-acid glycoprotein (₁-AGP) were investigated using circular dichroism (CD) measurements. Extrinsic Cotton effects were generated by the binding of drugs to ₁-AGP. The CD data suggested the presence of a single binding site on the ₁-AGP molecule. The induced ellipticities of the acidic drug–₁-AGP system decreased with increasing pH, while the ellipticities for the basic drugs increased with pH. The ellipticities for all drugs were reduced by the addition of fatty acids. Furthermore, the induced ellipticities decreased in the presence of cesium chloride for basic drugs bound to ₁-AGP. The extrinsic Cotton effects therefore appear to result from hydrophobic interaction with ₁-AGP for the acidic drugs and from hydrophobic and electrostatic interactions for the basic drugs.     

Immunoglobulin mimicry by Hepatitis C Virus envelope protein E2

Hepatitis C virus (HCV) establishes persistent infection in the majority of infected individuals. The currently accepted hypothesis of immune evasion by antigenic variation in hypervariable region 1 (HVR1) of glycoprotein E2 does not however, explain the lack of subsequent immune recognition. Here, we show that the N-terminal region of E2 is antigenically and structurally similar to human immunoglobulin (Ig) variable domains. E2 is recognized by anti-human IgG antibodies and also possesses common amino acid (aa) sequence features of the conserved v-gene framework regions of human Ig light chains in particular but also heavy chains and T cell receptors. Using a position specific scoring system, the degree of similarity of HVR1 to Ig types correlated with immune escape and persistence in humans and experimentally infected chimpanzees. We propose a unique role for threshold levels of Ig molecular mimicry in HCV biology that not only advances our concept of viral immune escape and persistent infection but also provides insight into host-dependent disease patterns.     

Predominant and stable T cell responses to regions of myelin basic protein can be detected in individual patients with multiple sclerosis

T lymphocytes from patients with multiple sclerosis (MS) recognize multiple myelin basic protein (MBP) epitopes. This situation complicates the design of specific immunotherapies. We investigated to which extent the T cell response to MBP is heterogeneous in single subjects in terms of preferentially recognized regions of the molecule, major histocompatibility complex (MHC) restriction, and stability over time. From each of nine patients with MS, a minimum of six MBP-specific T lymphocyte lines (TLL) were assayed for the proliferative response to a panel of overlapping peptides, encompassing the whole MBP. Predominant Tcell recognitions of distinct MBP regions were present in three patients, all HLA-DR2⁺, independently of the clinical features of their disease. Tcell reactivity was preferentially directed to residues 16-38 in one patient. In this case the response was also stable over time, during different phases of the disease. Predominant reactivity to residues 86-99 was detected in the two other DR2⁺ patients. In each of the patients with other HLA-DR haplotypes (DR2^?), as well as in three DR2⁺ non-MS donors, the Tcell response to MBP appeared to be considerably more heterogeneous. The HLA restriction element varied among TLL recognizing the same MBP region, even when raised from the same individual. The genomic HLA typing, performed on the DRB1 and DRB5 genes in the DR2⁺ subjects, showed no obvious correspondence between preferential responses to regions of MBP and HLA-DR2 subtypes. In this context, a simple, new method for the genomic typing of the HLA-DRB1 gene in individuals with the HLA-DR2 serological specificity is also described. We conclude that predominant and stable T cell responses to a single MBP region can be detected in some patients with MS. In these individuals, the MHC restriction of the T cell recognition of predominant regions appears to be variable. Polymorphisms of the HLA-DR2 gene products alone do not account for the selection of the dominant MBP Tcell epitope.     

糖尿病小鼠视网膜碱性成纤维细胞生长因子的表达及细胞损害的电镜观察

目的：为临床研究提供形态学资料。方法：用免疫组化方法，观察碱性成纤维细胞生长因子(bFGF)在糖尿病小鼠视网膜的分布及表达密度；用透射电镜观察不同病程视网膜细胞的损害情况。结果：糖尿病及正常小鼠视网膜各层细胞均表达bFGF，反应强度和密度不同。发病组自6月龄起，居于大血管周围的阳性节细胞密度增加；不同病程bFGF的表达有不同程度的增加。随糖尿病病程延长，细胞超微结构受到不同程度的损害。结论：糖尿病时增多的bFGF直接或间接作用于血管内皮细胞和平滑肌细胞，刺激二者增殖，促进微血管病变的发生；另一方面，减弱视细胞与双极细胞间的信息传递，对糖尿病性盲的发生起重要作用。同时，各种细胞的超微结构及相应的功能也受到不同程度的损害。     

Cord blood contains cells secreting antibodies to nervous system components.

Umbilical cord blood of newborns and peripheral blood of healthy adults were investigated by an immunospot assay for cells secreting IgG, IgA and IgM antibodies against myelin basic protein (MBP), proteolipid protein (PLP), myelin-associated glycoprotein (MAG) and myelin oligodendrocyte glycoprotein (MOG) which represent putative antigens for an autoimmune attack in multiple sclerosis (MS) and against acetylcholine receptor (AChR) which is considered an important autoantigen in myasthenia gravis. Cells secreting antibodies against one or more of these autoantigens were detected in 18 out of 24 newborns, and in eight out of 20 adults. Eight of the cord blood samples contained cells secreting antibodies of IgG, IgA and/or IgM isotypes to one antigen, five to two antigens, two to three antigens, two to four antigens, and one to five antigens. Most prominent were anti-MBP IgG antibody secreting cells which were detected in 13 newborns at a mean number of 1/20,000 cord blood cells, and in six adults at a mean number of 1/10(5) peripheral blood cells. Anti-AChR IgG antibody secreting cells were detected in four out of 12 newborns versus four out of 14 peripheral blood specimens, at mean values of 1/10(5) cells in both instances. Cells secreting autoantibodies of IgA and IgM isotypes were less frequent both in cord blood and peripheral blood. The occurrence of nervous tissue autoantibody secreting cells in newborns must be related to a possible primary role of such autoantibodies in MS and myasthenia gravis.     

Clonal expansion of myelin basic protein-reactive T cells in patients with multiple sclerosis: Restricted T cell receptor V gene rearrangements and CDR3 sequence

Myelin basic protein (MBP)-reactive T cells are thought to play an important role in the pathogenesis of multiple sclerosis (MS). In some patients with MS, these autoreactive T cells display a limited heterogeneity in their epitope recognition and T cell receptor (TCR) variable (V) gene usage. These individual-dependent properties of MBP-reactive T cells have led to the speculation that they may represent clonal expansion in vivo in some MS patients. In the present study, 51 MBP-reactive T cell clones derived from patients with MS and healthy individuals were examined for their epitope recognition and the TCR Vα and Vβ gene rearrangements. The V gene junctional region sequences of identified α and β genes were further analyzed to probe their clonal origins, as the sequences are unique for individual clones. Our data showed that 26 clones derived from nine patients with MS shared a predominant reactivity to the immunodominant regions of MBP, 84–102, 110–129 and 143–168, and used various TCR Vα and Vβ rearrangements. The V gene usage of the clones was restricted to certain Vα Vβ combination(s) in a given MS patient, but varied among different patients. The sequence analysis revealed that the clones generated from a given patient shared a limited or a single junctional region sequence pattern(s), indicating their oligoclonal or monoclonal origin(s). In contrast, 25 MBP-reactive T cell clones derived from normal individuals exhibited unfocused epitope recognition and V gene usage. Thus, the limited heterogeneity of MBP-reactive T cells in their structural and functional charactertistics reflects their clonal expansion in vivo in some patients with MS.