Agglutinating specificity for LW factor in guinea pig and rabbit anti-Rh serums

Serums produced in guinea pigs or rabbits inocutlated with monkey (rhesuts or baboon) or human red cells contain the same high-incidence agglutinating activity found in human antiLW serumls. After one absorption with LW-negative blood cells. anti-LW specificity, was observed with stronger reactions on Rh-positive than Rh-megative cells. The 85-percent specificity was obtained after complete absorption with Rh-negative blood.     

Inherited c'2 deficiency in man: lack of immunochemically detectable c'2 protein in serums from deficient individuals

Monospecific antiserum to highly purified second component of human complement (C'2) was used to show the absence of the protein from the serums of four persons homozygous for a hereditary deficiency of second-component activity. Serum from an individual heterozygous for the deficiency contained a reduced amount of this protein as compared to the concentration in normal serum. These observations indicate that genetic deficiency of this component is due to failure of synthesis of normal amounts of the protein rather than to synthesis of an antigenically related, hemolytically inactive analog of C'2.     

Antibodies to polynucleotides: distribution in human serums

Hemagglutination procedures were used to determine the distribution of antibodies to native DNA, single-stranded DNA, and double-stranded RNA. Antibodies to all three polynucleotides were found in a high percentage of the serums of patients with systemic lupus erythematosus. Antibodies to native DNA occurred almost exclusively in serums of patients in the active stages of systemic lupus erythematosus, whereas antibodies to single-stranded DNA were observed in the serums of patients with several diseases and of some normal individuals.     

Production of hemadsorption-negative areas by serums containing Australia antigen

Exposure of human Wi-38 cells to human serums containing Australia antigen, and presumably serum hepatitis virus, renders the cells refractory to infection by Newcastle disease virus as detected by the hemadsorption-negative plaque test for intrinsic interference. Induction of the Newcastle disease virus refractory state could be passed in cell culture with up to a 1 : 100,000 dilution of material obtained from cells "infected" with serums containing Australia antigen after filtration (0.45-microm pores) and heating to 60 degrees C for 1 hour. Human antiserums to the Australia antigen prevented induction of the Newcastle disease virus refractory state.     

Identification of the volatile factor involved in spermatocyte differentiation in vitro

Ketchel and Williams postulated a "volatile factor" which participates in the differentiation of insect spermatocytes in vitro. It was found not to be a specific product of developing cysts. Instead, its effects are duplicated by a number of reagents which have only a high water content in common. The hypothesis that the volatile factor is water was experimentally confirmed.     

Differential reactivity of human serums with early antigens induced by Epstein-Barr virus

Inoculation of 64-10 or Raji cultures with Epstein-Barr virus derived from the HRI-K clone of the P3J Burkitt's lymphoma line caused abortive infections in most of the lymphoblastoid cells with synthesis of "early antigens" but few, if any, capsids. Antibodies to early antigens were detected by indirect immunofluorescence in serums of many patients with infectious mononucleosis, Burkitt's lymphoma, or nasopharyngeal carcinoma. These antibodies were rarely present in other serums even though some of them showed high titers of antibodies to Epstein-Barr virus when assayed on EB3 Burkitt tumor cells; they also prevented synthesis of early antigens, provided the serums were mixed with the virus prior to inoculation. Antibodies to early antigens possibly reflect current or recent disease processes that are associated with the virus.     

Genetic factors and polypeptide chain subclasses of human immunoglobulin G detected in chimpanzee serums

The Gm and Inv genetic factors, characteristic antigens of human immunoglobulin G, were detected in chimpanzee serums. All animals tested were Gm(a+, x-, b(l)-, b(2)-, b(3)+, b(4)+). Polymorphism was demonstrated for factors Gm(c), Inv(l), and Inv(b). Three of the subclasses of heavy polypeptide chains and both types of light polypeptide chains that are present in human immunoglobulin G were identified in chimpanzee serums.     

Cytotoxic antibody in normal human serums reactive with tumor cells from acute lymphocytic leukemia

Serums showing complement-dependent cytotoxic reactions to acute lymphocytic leukemia cells were detected in three normal unimmunized subjects. These serums were reactive with tumor cells from 514 (514 tested) acute lymphocytic leukemia patients, and three (12 tested) patients with acute myelocytic leukemia; they did not react with tumor cells from patients with acute monocytic leukemia (two tested), with chronic lymphocytic leukemia (two tested) or with leukolymphosarcoma (two tested); nor did they react with normal lymphocytes from 52 different donors. These reactive serums appear to recognize antigens primarily associated with acute lymphocytic leukemia.     

血管内皮生长因子对水牛卵母细胞体外受精的影响

[目的]探讨血管内皮生长因子（Vascular endothelial growth factor,VEGF）对水牛卵母细胞体外受精的影响,为优化水牛卵母细胞体外培养体系及提高水牛体外胚胎生产效率奠定基础.[方法]以带有3层以上卵丘细胞的卵丘—卵母细胞复合体（COCs）为材料,分别在水牛卵母细胞体外成熟液和受精液中添加重组人VEGF165,研究VEGF对水牛卵母细胞体外成熟、体外受精和早期胚胎发育的影响.[结果]在成熟液中添加10ng/mLVEGF,水牛卵母细胞的第一极体排出率由57.3％提高到72.3％,差异显著（P＜0.05,下同）;体外受精后的受精卵分裂率由41.0％显著提高到53.3％.在受精液中添加10 ng/mL VEGF,水牛体外受精的受精卵分裂率由41.9％提高到63.0％,差异极显著（P＜0.01,下同）,囊胚形成率由17.0％显著提高到32.6％.在成熟液和受精液中同时添加10ng/mLVEGF,水牛体外受精的受精卵分裂率和囊胚形成率由43.4％和19.0％极显著提高到64.3％和27.2％,囊胚细胞数由89.5显著提高到106.8.[结论]VEGF能促进水牛卵母细胞体外成熟、体外受精及早期胚胎的发育,因此可将VEGF用于水牛卵母细胞体外受精体系的优化,提高水牛体外胚胎生产效率.     

Microscale nutrient patches in planktonic habitats shown by chemotactic bacteria

Are nutrients available to microbial communities in micropatches long enough to influence growth and competition? And what are the sources of such patches? To answer these questions, the swimming behavior of chemotactic bacteria in seawater samples was examined. Clusters of bacteria formed in conjunction with cell lysis and excretion by protozoa. These point sources of nutrients spread into spherical patches a few millimeters in diameter and sustained swarms of bacteria for about 10 minutes. Within that time, a large proportion of the nutrients was encountered by bacteria, chemotactic and nonchemotactic alike. Chemotaxis is advantageous for bacteria using patches over a certain size.     

A macrophage-derived factor required by plasmacytomas for survival and proliferation in vitro

Plasmacytoma (PCT) cell lines dependent for proliferation and survival on a factor elaborated by the murine macrophage cell line, P388D1, were established in vitro. Adherent peritoneal cells induced by pristane produced 50-fold greater amounts of this activity in vitro than did resident cells. The molecules responsible for plasmacytoma growth were distinct from a number of characterized factors including interleukin-1, -2, and -3, macrophage colony-stimulating factor, B-cell stimulatory factor-1, B-cell growth factor II, epidermal growth factor, transforming growth factor-beta, and gamma- and beta-interferon, none of which were able to support the growth of the factor-dependent PCT cell lines. These results suggest that PCT growth factor may be a novel factor that has not been previously characterized and, further, that its production is associated with the pristane-induced, chronic peritoneal inflammatory response that precedes plasmacytoma formation.     

A macrophage factor inhibits adipocyte gene expression: an in vitro model of cachexia

Certain infections and malignancies in mammals cause the development of a condition known as cachexia in which the animal continues to lose weight, often while consuming an adequate diet. When macrophages are stimulated with an endotoxin, they produce a factor or factors, termed cachectin, that inhibits the activity of fat-producing (lipogenic) enzymes in cultured adipocytes. This effect may reflect one of the physiological bases for cachexia. In the present study, clones of complementary DNA from genes whose expression is increased during the differentiation of adipocytes were used to study the molecular basis of cachectin's actions. In the presence of cachectin, the expression of the corresponding genes was reversibly and specifically inhibited. Furthermore, when mature adipocytes were exposed to cachectin, the messenger RNA's of those genes diminished and rapidly approached the levels present before differentiation.     

Ethanol neurotoxicity: effects on neurite formation and neurotrophic factor production in vitro

The effects of ethanol on chick embryo sensory and spinal cord neurons growing on one of several biological substrates (poly-D-lysine, laminin, or neuron-produced neurite-promoting materials) were examined. Ethanol inhibited process formation by the neurons in a dose-dependent manner and inhibited the production of neurotrophic factors. Neuronal attachment to the substrates, survival of attached neurons, and receptor interactions of sensory neurons with nerve growth factor were not influenced by ethanol. It appears that ethanol alters certain metabolic characteristics of developing neurons.