中西医结合医院单病种的质量管理及其作用

针对中西医结合医院单病种质量评定没有现成的、规范的标准的现状,就中西医结合单病种的质量管理方法及其在中西医结合医院建设中的作用进行了论述。     

Leukaemia Inhibitory Factor or Related Factors Promote the Differentiation of Neuronal and Astrocytic Precursors within the Developing Murine Spinal Cord

Previously we have shown that leukaemia inhibitory factor (LIF) potentiates the development of murine spinal cord neurons in vitro , suggesting that it, or related factors, may play an important regulatory role in neuronal development. We have further investigated this role and show here that the generation of neurons in cultures of embryonic day 10 spinal cord cells is inhibited by antibodies to the β subunit of the LIF receptor. Since there are more undifferentiated precursors in antibody-treated cultures than in control and LIF-treated cultures, it is concluded that the primary action of LIF, or related molecules, is to promote neuronal differentiation, not precursor survival. In addition, the failure of LIF to support neuronal survival in the period immediately following differentiation suggests that the increased numbers of neurons generated with LIF are not attributable to its neurotrophic action. By selecting neuronal precursors on the basis of their inability to express class I major histocompatibility complex molecules, it was shown that LIF acted directly upon these cells and not via an intermediary cell. LIF also appears to be involved in regulating the differentiation of astrocytes, since it increases the number of glial fibrillary protein (GFAP)-positive cells present in the cultures and since the spontaneous production of GFAP-positive cells is blocked by antibodies to the LIF β receptor. These findings suggest that LIF or related factors promote the differentiation of neural precursors in the spinal cord, but that they are not involved in preferentially promoting precursors down a specific differentiation pathway.     

The multifunctionality of FGF-2 in the adrenal medulla

 Chromaffin cells of the adrenal medulla and their tumor counterparts, the pheochromocytoma (PC12) cells, are well-established model systems in neurobiology. The development of sympathoadrenal progenitor cells to chromaffin cells can be studied with regard to developmental signals which trigger the differentiation. With regard to potential treatments of neurological disorders like Parkinson’s disease chromaffin cell grafting can be used as one therapeutical approach. The beneficial effect of chromaffin cell grafts is possibly not only related to the release of dopamine but may also be linked to the release of growth factors. One of the growth factors that is synthesized by chromaffin and PC12 cells is basic fibroblast growth factor (FGF-2). The experimental data available so far, are in agreement with different functional roles of FGF-2. This article summarizes the putative physiological functions of FGF-2 in the adrenal medulla. Three differential functional roles of FGF-2 are discussed: (1) as a differentiation factor for sympathoadrenal progenitor cells; (2) as a target-derived neurotrophic factor for preganglionic sympathetic neurons which innervate adrenal medullary cells; (3) as an auto-/paracrine factor in the adrenal medulla. Accepted: 21 August 1996     

Characterization and phenotypic analysis of differentiating CD34+human bone marrow cells in liquid culture

Abstract: Our current understanding of human haematopoietic stem cell biology is based in part on the characterization of human CD34⁺ bone marrow cell differentiation in vitro. CD34 is highly expressed on early stem cells and haematopoietic progenitor cells with clonogenic potential and is gradually lost during differentiation and commitment. However, CD71 (transferrin receptor) is expressed at low levels on early stem cells and generally increases during haematopoietic progenitor cell proliferation. We reasoned that the combination of these surface markers would provide a useful framework for the simultaneous analysis of multiple lineage differentiation of CD34⁺ haematopoietic progenitor cells in liquid culture. In this report, we identify the phenotype of distinct subpopulations of myeloid, erythroid and lymphoid cells in liquid suspension culture using differential expression of CD34 vs. CD71 in combination with specific lineage markers. Freshly isolated human CD34⁺ bone marrow cells were introduced into suspension culture and monitored over a 6-d period using 3-colour flow cytometry. This is the first demonstration that differential expression of CD34 vs. CD71 can be used to simultaneously monitor differentiation of multiple haematopoietic cell lineages in liquid suspension culture, facilitating the study of cytokine-, drug- or chemical-induced alterations in haematopoietic progenitor cell differentiation in vitro.     

Neonatal exposure to estradiol prevents the expression of ovarian hormone-induced luteinizing hormone and prolactin surges in adulthood but not antecedent changes in neuropeptide Y or adrenergic transmitter activity: Implications for sexual differentiation of gonadotropin secretion

Sex differences in adult patterns of mating behavior and gonadotropin secretion in rats are determined in part by the presence or absence of gonadal steroids during a perinatal critical period. For example, male rats and female rats exposed neonatally to androgen do not exhibit LH surge patterns when treated appropriately with ovarian hormones in adulthood, and there is evidence that this may be due to a failure of ovarian hormones to activate the hypothalamic neuronal systems that stimulate LH secretion in such animals. Because considerable evidence suggests that estradiol formed centrally from testosterone is responsible for the permanent defeminization of mating behavior and gonadotropin secretion, the present studies compared normal females with normal males and with females treated neonatally with estradiol on the ability of ovarian hormones to induce several important neurochemical changes antecedent to the LH surge, including changes in neuropeptide Y (NPY) and LH-releasing hormone (LHRH) concentrations in the median eminence, as well as changes in turnover rates for catecholamine transmitters in the medial basal hypothalamus and medial preoptic area. Normal ovariectomized female rats responded to sequential treatment with estradiol followed by progesterone with afternoon LH and prolactin (PRL) surges, and with sequential accumulation followed by decline in concentrations of LHRH and NPY in the median eminence prior to the LH surge. In addition, administration of progesterone increased the turnover rates of norepinephrine (NE) and epinephrine (EPI) in the arcuate-median eminence region of normal females. Gonadectomized male rats receiving the same ovarian hormone treatment failed to exhibit LH or PRL surges and displayed none of the changes in neurotransmitter turnover or peptide concentrations characteristically seen in the normal female. Unexpectedly however, when females that were treated with estradiol benzoate on days 1–3 postpartum were ovariectomized and treated with ovarian hormones in adulthood, they showed the same accumulation/decline in median eminence NPY concentrations and the same activation of NE and EPI turnover in the arcuate-median eminence region as normal females, even though they showed no LH or PRL surges or changes in median eminence LHRH concentrations. These results suggest that estradiol may not mediate all of the defeminizing actions of androgen exerted during the early neonatal period, and particularly those actions that result in a lack of responsiveness in central noradrenergic, adrenergic and NPY systems in adulthood. However, an action of neonatal estradiol may result in uncoupling of the LHRH neurosecretory system from normal excitatory neurochemical influences.     

诱导兔骨髓基质细胞向神经干细胞分化的初步实验研究

目的：观察兔骨髓基质细胞体外培养的生长行为及增殖、分化情况，探讨由骨髓分离培养神经干细胞的可行性和有效性。方法：无菌条件下行骨穿术，密度梯度离心分离获取骨髓基质细胞，利用多种增殖、分化诱导因子和神经干细胞培养液进行培养、分化诱导，用免疫细胞化学方法进行鉴定。结朵：骨髓基质细胞在体外培养中能形成NESTIN抗原阳性的细胞克隆团，进一步分化，部分细胞胞体增大并出芽，逐渐发育成为较成熟的长突起细胞，长突起相互连接、交织成网并建立纤维联系。结论：骨髓基质细胞具有较强的自我更新能力和多向分化潜能，易于取材、体外培养和增殖，在一定诱导条件下可以生成神经干细胞。     

三氧化二砷与维甲酸联合作用在NB4,MR2细胞系中的体外研究

目的：观察三氧化二砷(As2O3)和全反式维甲酸(ATRA)联合作用对NB4，MR2不同亚型急性早幼粒白血病细胞株，诱导分化、增殖、凋亡的影响。方法:以NB4，MR2为体外模型，利用细胞生长曲线、台盼蓝拒染法、MTT法、NBT、细胞形态Wrigh‘s-Gimesa染色，观察细胞增殖、分化、凋亡的相互作用。结果：NB4细胞株：0．5μmol/L As2O3与10^-6mol/L ATRA对细胞增殖、分化、凋亡呈现拮抗，而0．5μmol/L As2O3与(10^-7--10^-8mol/L)ATRA呈现协同；MR2细胞株：0．5μmol/L As2O3与10^-6mol/L ATRA对细胞增殖、分化、凋亡呈现协同。结论：As2O3与全反式维甲酸协同效应呈现不同细胞、剂量的特异性，MR2细胞株协同效应明显强于NB4细胞株。     

Liposomal 1,25 (OH)2 vitamin D3 compounds block proliferation and induce differentiation in myelomonocytic leukaemia cells

The vitamin D₃ derived hormone 1,25 (OH)₂ vitamin D₃ (1,25 D₃) is able to induce growth arrest and differentiation in myelomonocytic leukaemia cells. In order to allow for specific delivery to leukaemic cells the lipophilic compound was incorporated into the lipid membranes of liposomes. Liposomal 1,25 D₃ reduced proliferation as measured by ³H-thymidine incorporation in HL60 leukaemia cells by up to 60%. When liposomes were prepared at different concentrations of 1,25 D₃ 65% inhibition was achieved at 48 n M . The MC 1288 stereoisomer of 1,25 D₃ was more potent and had the same activity at 48 n M .
The effect of the liposomal compounds was specific to myeloid cells as they reduced proliferation in myelomonocytic HL60, monoblastic U937 and monocytic Mono Mac 6 cells but not in the T-cell lines Jurkat and Molt 4.
The antiproliferative effect of liposomal 1,25 D₃ was associated with an induction of differentiation since treated HL60 cells showed a monocytic morphology, increased expression of CD14 and decreased expression of CD33.
When peripheral blood leukaemic cells from M4 and M5 acute myeloid leukaemia (AML) patients were admixed with liposomal compounds an antiproliferative effect was seen in all five cases, including the two cases where free compounds led to enhanced growth. Liposomal delivery of 1,25 (OH)₂ vitamin D₃ may offer a novel approach to treatment of myelomonocytic leukaemia.     

HMBA诱导MEC—1细胞分化角蛋白染色的变化

用六亚甲基二乙酰胺（ＨＭＢＡ）作为分化诱导剂，对人粘液表皮样癌细胞系ＭＥＣ－１细胞中角蛋白进行染色，结果发现高分子量角蛋白在被诱导细胞中含量明显增高。分光光度仪检测角蛋白含量，诱导组ｘ±ｓ为２１８±５１，对照组为１４９±４７，两组有显著差异（Ｐ＜００１），这可能与细胞分化有关。     

Depriving neonatal rats of milk from early lactation has long-term consequences on mammotrope development

The sudden appearance of prolactin-releasing cells during the early postnatal period of the rat is initiated by a small milk-borne peptide. Depriving newborn rats of this early milk factor severely retards mammotrope differentiation during the neonatal period. In the present work, we extend our study of early milk deprivation to the adult. To this end, newborn litters were crossfostered onto mothers that had given birth the same day or one week earlier in order to deprive pups in the latter group of early milk. At 5, 15, and 30 d of age, rats deprived of such milk had decreased percentages of mammotropes (as measured by reverse hemolytic plaque assay, RHPA) when compared to nondeprived animals (P<0.05). By 45 d, the percentage of mammotropes was similar for the two crossfostered groups (P>0.1) and this persisted through d 60. Subsequently, we assessed the secretory capacity of mammotropes from 60-d old rats to secretagogues and found that early milk deprivation had no effect on basal prolactin release (P>0.1), but that it augmented hormone secretion evoked by thyrotropin-releasing hormone (TRH, 100 nM; P<0.01). The inhibitory response to dopamine (DA; 1 μM) and the stimulatory response to angiotensin II (AGII; 100 nM) were not altered by early milk deprivation (P>0.1). Taken together, these results demonstrate that factors in milk from early lactation are required for normal mammotrope differentiation, and that the delay induced by early milk deprivation leads to altered secretory function of mammotropes in adult animals.