利用IL－3／GM－CSF融合蛋白（PIXY－321）扩增脐血造血细胞方法的初步建立

利用单克隆抗体免疫磁珠吸附方法分离脐血ＣＤ３４＋细胞,并观察了ＩＬ３／ＧＭＣＳＦ融合蛋白（ＰＩＸＹ３２１）对脐血ＣＤ３４＋细胞的刺激作用。ＰＩＸＹ３２１对脐血ＣＤ３４＋细胞扩增作用大于ＩＬ３和ＧＭＣＳＦ单独及联合应用。在液体培养条件下,每毫升２０ｎｇＰＩＸＹ３２１可有效地扩增脐血造血祖细胞,适宜扩增时间为５－８天,扩增后造血祖细胞的数量可达扩增前的８－１０倍,从而初步建立了一种简单可行的脐血造血细胞扩增方法。     

硒对培养人胚肝细胞Ⅲ型前胶原,羟脯氨酸合成的影响

原代培养人胚肝细胞经１．１５６×１０￣(－７）ｍｏｌ／Ｌ硒预处理４ｈ,加入２０ｍｍｏｌ／Ｌ四氟化碳作用２０ｈ,观察硒对其Ⅲ型前胶原（ＰＣⅢ）和羟脯氨酸（Ｈｙｐ）生成的影响。结果培养液中ＰＣⅢ水平、细胞内Ｈｙｐ含量及细胞内外丙二醛（ＭＤＡ）水平均降低,与未加硒对照组比较差别有显著性（Ｐ＜０．０１）。而硒谷腕甘肽过氧化物酶（Ｓｅ－ＧＳＨ－ＰＸ）活性则较对照组显著增高（Ｐ＜０．００１）,且ＰＣⅢ水平与Ｓｅ－ＧＳＨ－Ｐ＿Ｘ／ＭＤＡ比值呈负相关（ｒ＝－０．９１５６,Ｐ＜０．０１）。提示硒可提高Ｓｅ－ＧＳＨ－Ｐ＿Ｘ／ＭＤＡ比值,抑制脂质过氧化激发的肝细胞胶原合成。     

鸡胚血液中原始生殖细胞的分离及其培养的研究

从孵化４８～５５小时鸡胚中抽取血液,每只胚胎可获血液２～６μｌ左右。一步法离心分离原始生殖细胞,可使其浓度由０．１％以下提高到５０％以上。将多余血细胞用微量吸管移走后,加入添加１０％胎牛血清的ＴＣＭ—１９９做为培养基,３７．５℃,５％ＣＯ２,９５％空气,饱和湿度下培养,原始生殖细胞可成活２４小时左右。     

Human papillomavirus is associated with monoclonal gammopathies of unknown significance

When monoclonal gammopathies arise in persons without evidence of plasma cell malignancy or lymphoproliferative disease, the term monoclonal gammopathy of unknown significance (MGUS) can be used. MGUS is believed to be the preneoplastic phase of lymphoproliferative diseases because many of these patients eventually develop malignant disease, mainly multiple myeloma. We have previously identified human papillomavirus (HPV) in a chronic benign plasma cell tumor of the cervix and in the bone marrow of multiple-myeloma patients. In the following study, we expanded upon our initial observation by analyzing 14 patients with MGUS. Bone marrow biopsies of the patients were analyzed for HPV sequences using polymerase chain reaction (PCR) and in situ hybridization. Normal controls included 26 bone marrow specimens, 24 analyzed by PCR and two by in situ hybridization. A significant association was found to exist between HPV and MGUS (p=0.001). Among 14 patients iwth MGUS, HPV sequences have been identified in 10 of the bone marrow biopsies. These results suggest that HPV can reside in the bone marrow of a premalignant lymphoproliferative disease.     

Development of secondary pine forests after pine wilt disease in western Japan

Abstract. The development of secondary Pinus densiflora (Japanese red pine) forests after pine wilt disease was studied through phytosociological analysis, estimation of forest structure before disease and size-structure, tree ring and stem analyses. Following the end of the disease, the growth of previously suppressed small oak trees was accelerated. This is quite different from the development of forests following fire, which starts with the establishment of pine seedlings. Pine wilt disease shifted the dominance of secondary forests from Pinus densiflora to Quercus serrata oak forest. In pine forests, disturbance by fire is important for forest maintenance. In contrast, disturbance by pine wilt disease leads to an acceleration of succession from pine forest to oak forest.     

Inhibition of parathormone-stimulated bone resorption by type I interferon

The effect of Type I interferon on bone resorption was studied by measuring its effect on parathormone-stimulated calcium release from neonatal murine calvaria in vitro. A pure human recombinant leukocyte interferon hybrid of the A and D subtypes was used, which has high antiviral activity on mouse cells. Calcium release was inhibited in a dose dependent fashion with 50% inhibition at about 10(-10) M or 600 U/ml, and the inhibition was reversible. The presence of interferon was required before or during the activation phase of the resorptive response, when the formation of osteoclasts from precursor cells would occur. When added to actively resorbing bone it had no effect. The data suggest that Type I interferon can inhibit the parathormone-regulated development of active osteoclasts, possibly by inhibiting osteoclast precursor differentiation.     

Distribution of actin in migrating leukocytes in vivo

Summary Blood cells proliferate extravascularly in the bone marrow and enter the circulation by migrating through endothelial cells of venous blood sinuses. This migration, or diapedesis, was suspected to involve actin. To test for the presence and distribution of actin, sections of rat bone marrow were examined by indirect immunocytochemistry. Affinity purified rabbit antichicken gizzard actin antibody, and goat-antirabbit IgG-FITC, or goat antirabbit IgG colloidal gold probes were used. The migrating cell contacts the endothelial cell and forms a podosome (a cortical bleb). Immunocytochemistry shows this region to contain actin. As diapedesis proceeds the podosome deforms, then breaches the endothelial cell. At this time the anterior portion of the leukocyte shows heavy labeling for actin. When the migratory cell traverses approximately half of its length through the endothelial cell, actin appears prominent in the caudal region of the cell. The immunocytochemical data suggest that actin is nonrandomly distributed in leukocytes undergoing diapedesis and may be a component of the force-generating mechanism responsible for this transcellular migratory event.Supported in part by grants from the American Cancer Society, Illinois Division, Inc. (83-4), and NIH (GM 28397)     

Studies on bone marrow histogenesis: Morphometric and autoradiographic studies of regenerating marrow stroma in extramedullary autoimplants and after evacuation of marrow cavity

Summary The marrow cavity of the rat tibia was mechanically evacuated and autoimplanted to the subcutaneous tissue. The regenerative process which restored the integrity of marrow stroma and hemopoiesis, was morphometrically evaluated in whole mount of tibia. Following evacuation, the clot filled the cavity. The granulation tissue then appeared and expanded, penetrating and replacing the clot. The fibroblasts of the granulation tissue differentiated into osteoblasts forming osteoid bone. Within its interstices, the primordial marrow consisting of loose connective tissue and vascular sinuses appeared and hemopoiesis resumed. Expansion of hemopoiesis resulted in the resorption of bone and within three weeks the tibial cavity was restored to the pre-evacuation state.Autoradiography indicated that the labeling index was initially high in fibroblasts and osteoblasts but was subsequently reduced while it increased in osteocytes, cells of Haversian canals, stromal and hemopoietic cells of marrow. The finding is in disagreement with the view that the regenerative process originates from the Haversian canal. When the label was introduced on day 4 post-operatively, it subsequently appeared in osteocytes, cells of Haversian canal, stromal elements of the marrow, but not in the hemopoietic cells. This indicates complete dissociation of marrow stroma and hemopoietic stem cell.Supported by NASA Contract NSG 9061. Mehdi Tavassoli is the recipient of a CRD Award AM-70551     

A comparison of two methods for the microscopic determination of age at death.

The precision and accuracy of the Kerley and Ahlqvist-Damsten microscopic methods of age determination are compared. Both methods were applied to the same sample of 40 femoral thin sections of documented age at death. The results indicate that (1) both methods can be used with equal precision, as suggested by comparable observer errors; and (2) the Kerley method produces overall more accurate age estimates. The low previously published standard error of the Ahlqvist-Damsten method (6.71 years) apparently results from the uneven age distribution and small size (20) of their sample.