The water-soluble component of Salvia miltiorrhiza Bge can promote macrophage synthesis of C4 in vivo and in vitro

A water-soluble component extracted from Salvia miltiorrhiza Bge has been used for many years in traditional Chinese medicine ('huo xie hua yu') for the treatment of the hyperviscosity syndrome. We demonstrate here that this extract promotes macrophage proliferation in vitro and enhances macrophage synthesis of the C4 component of complement. No increase in synthesis of other complement components by macrophages was observed. In a group of 20 patients with the hyperviscosity syndrome treated with an aqueous extract of Salvia, serum levels of C4 rose significantly over the course of treatment (mean pretreatment level 37.4 mg%, mean posttreatment level, 43.5 mg%; p < 0.01). The rise in C4 levels closely correlated with the disappearance of the patients' clinical symptoms.

The initiation-promotion-progression model of rat hepatocarcinogenesis

Carcinogenesis is a multistage process consisting of the three distinct stages: initiation, promotion, and progression. The initiation-promotion-progression (IPP) protocol models these stages and establishes a method whereby agents that possess a carcinogenic risk can be classified as acting primarily at any one or combination of these stages. In one hepatocarcinogenesis IPP protocol, rats were initiated with 10 mg of diethylnitrosamine/kg body wt at 5 days of age, started on the promoting agent phenobarbital at weaning, subjected to a 70% partial hepatectomy at 6 months, and, at the peak of proliferation, given a putative progressor agent, ethylnitrosourea ([ENU] 100 mg/kg, ip) or hydroxy-urea ([HU] 3 x 150 mg/kg, ip). Administration of the promoting agent was discontinued after the progressor agent was given, and the rats were sacrificed 6 months later. The number and volume fraction of promoter-independent (growth in the absence of the promoting agent) altered hepatic foci (AHF) were then determined by quantitative stereology. The number of such AHF increased with either ENU or HU treatment compared with animals not given a progressor agent. In addition, hepatocytes isolated from animals subjected to an IPP regimen with ENU as the progressor agent exhibited a greater degree of chromosomal breakage and aneuploidy than animals not given a second initiator. A variation of this model, in which the promoting agent was maintained after administration of the progressor agent, was examined. In this IPP model, the number of heterogeneous AHF (foci-in-foci) increased after application of the progressor agent (ENU or HU). An increased incidence of hepatocellular carcinoma was also observed in animals subjected to the IPP protocol when promotion was maintained until sacrifice. Thus, the characteristics of progression--increased chromosomal damage, aneuploidy, growth of AHF in the absence of continued tumor promotion, the presence of foci-in-foci, and an increased incidence of malignant neoplasia--have been used as end points for the demonstration of progressor activity by ENU. In addition, the potential progressor activity of HU and benzene has been demonstrated with the IPP model of rat hepatocarcinogenesis.

Histopathology and immunohistopathology of lymph nodes of the first autopsy with HIV positivity in China

Nineteen lymph nodes of a HIV-positive boy were studied histologically and immunohistologically. According to Stutte's classification of HIV-related lymphadenopathy, 84% of the lymph nodes were at the third or fourth stages in relation to clinical status ARC/AIDS. Lymph follicle atrophy, angiogenesis, histiocytic proliferation and destruction of the normal reticulum frame were observed. Immunohistochemical studies showed most of the remaining lymphocytes to be T cells and changes in the distribution of S-100 positive cells. Ki 1 positive cells existed mainly at the second stage. The significance of these changes is discussed.

[Antibodies to extractable nuclear antigen polypeptides: detection and its clinical significance]

Using immunoblotting technique (IBT) and saline extracts of rabbit thymus powder as antigen, we detected seven autoantibodies i.e. anti-Sm, anti-RNP, anti-SSA, anti-SSB, anti-Scl-70, anti-Jo-1 and anti-ribosome with only a strip of blot. Comparison of IBT and counter-immunoelectrophoresis (CIE) showed that the antibodies against Sm in SLE could be detected more sensitively by IBT than by CIE (P < 0.01). And the antibodies against ribosome by IBT were much specific for SLE (P < 0.01). So the detection of antibodies against ENA polypeptides by IBT was helpful in the diagnosis of SLE. In rheumatic diseases, the antibodies against SSB could be detected more sensitively by IBT than by CIE (P < 0.05), while the antibodies against SSA could be detected more sensitively by CIE than by IBT (P < 0.01). The antibodies against Scl-70 and Jo-1 by IBT were much specific for PSS and PM/DM respectively (P < 0.01).

Myeloid and erythroid hemopoiesis supported by human bone marrow fibroblasts in vitro

The passages 0 and 3 purified human bone marrow fibroblast layers (FLs) were established by long-term liquid cultures. After 12-day coculture of stromal. cell-depleted marrow cell suspensions with passage 0 FLs, 68.33 +/- 4.04% of the hemopoietic colonies adhered to FLs was myeloid in nature and the other 31.67 +/- 4.04% was erythroid. There were still CFU-E (colony forming unit-erythroid), BFU-E (burst forming unit- erythroid), and CFU-GM (colony forming unit-granulocyte/macrophage) among the nonadherent cells. The media conditioned by passage 0 (F0-CM) and passage 3(F3-CM) FLs stimulated the growth of myeloid and erythroid (BFU-E) colonies. From these data, it is concluded that both FLs and the media conditioned by fibroblasts can stimulate myeloid and erythroid hemopoiesis.

Nuclear proteins and prolactin-induced annexin Icp35 gene transcription

Annexin Icp35 is the major PRL-stimulated gene in the pigeon cropsac. The regulation of its promoter has been studied by in vitro assays for nuclear protein binding and transcription. Proteins present in nuclear extracts of PRL-stimulated, but not control, pigeon cropsac contained factors which specifically bound to sequences within 73 base pairs upstream of the cp35 transcription start point. The binding of some of the factors was localized to a region between -32 and -73 by gel-shift assays. Cell-free transcription was used to determine whether the cp35 promoter could be influenced by factors present in cropsac nuclear extract. HeLa cell nuclear extract transcribed the cp35 gene at a basal rate. Transcription of the cp35 gene, but not adml, was synergistically enhanced by nuclear extract from PRL-stimulated cropsac. Nuclear extract from unstimulated pigeon cropsacs did not stimulate either cp35 or adml transcription. A template from which sequences upstream of the cp35 gene TATA box were deleted was transcribed by HeLa cell extract but unaffected by any cropsac factors. These results demonstrate that PRL can cause the expression of one or more nuclear factors that bind to 5'-flanking DNA of cp35 and activate the gene's transcription.

Ploidy and specific karyotypic changes during promotion with phenobarbital, 2,5,2',5'-tetrachlorobiphenyl, and/or 3,4,3'4'-tetrachlorobiphenyl in rat liver

Polychlorinated biphenyls are a group of industrial chemicals that are widely distributed in the environment. Since these compounds occur as mixtures, studies of their possible interactive effects are important. In order to determine whether an interaction of 2,5,2',5'-tetrachlorobiphenyl (TCB) with 3,4,3',4'-TCB occurs during multistage hepatocarcinogenesis in vivo, like that previously observed in lymphocytes in vitro (L. M. Sargent et al., Mutat. Res., 224: 79-88, 1989), we exposed rats to a single initiating dose of diethylnitrosamine (DEN), 10 mg/kg after a 70% partial hepatectomy, and subsequently to 0.1 ppm 3,4,3',4'-TCB and/or 10 ppm 2,5,2',5'-TCB in the diet for 1 year. Administration of each of the TCBs alone after DEN initiation resulted in a low incidence of chromosomal damage in hepatocytes; but when the two were given together after DEN initiation, there was a more than additive effect on this parameter at both 7 and 12 months which was highly significant. Administration of the TCBs alone or in combination in the absence of DEN initiation also resulted in chromosomal damage, approaching that seen in livers of animals initiated with DEN when sacrificed at 12 months. In animals receiving 0.05% phenobarbital for a 12-month period after initiation with DEN, a significant degree of chromosomal breakage and fragment formation occurred both in hepatocytes expressing the ectoenzyme gamma-glutamyltranspeptidase (GGT) and in those that were GGT negative. However, the GGT-negative cells showed a significantly lower incidence of chromosomal damage than the GGT-positive hepatocytes. Exposure to phenobarbital for 7 months after DEN initiation resulted in no significant chromosomal damage in hepatocytes, whether GGT positive or GGT negative. Some degree of specificity in chromosomal alterations was seen in hepatocytes of animals initiated with DEN and promoted either with a combination of TCBs or with phenobarbital. The most frequent alterations seen were a trisomy of chromosome 1 or of its long arm and a monosomy of chromosome 3 or its short arm. Some chromosome 7 aberrations were also seen. The highest frequency of specific aberrations occurred in hepatocytes from rats that also bore hepatocellular carcinomas, suggestive of the hypothesis that genes involved in the development of hepatic carcinoma may reside in chromosome 1 and/or 3 of the rat.

Non-linear phenomena in oxygen transport to tissue

A non-linear partial differential equation is analyzed using multiple scale techniques and similarity transformations in order to examine the role of hemoglobin and myoglobin in facilitating oxygen transport to tissue.

Analysis of egg granuloma formation in Schistosoma japonicum-infected mice treated with antibodies to interleukin-5 and gamma interferon

Schistosoma japonicum-infected mice were treated with antibodies to interleukin-5 (IL-5) or gamma interferon (IFN-gamma) from week 3 or 4 to week 10 of infection. Neither antibody affected egg production by the parasite, and neither had a consistent effect on the secretion of IFN-gamma or IL-5 cell-related cytokines by spleen cells from infected mice. Mice treated with antibody to murine IL-5 had only rare eosinophils in hepatic circumoval granulomas. Granulomas around single eggs were reduced in volume by a third, but hepatic fibrosis was unaffected. Treatment with antibody to murine IFN-gamma also reduced the size of granulomas and also did not affect hepatic fibrosis, which was measured as hydroxyproline. Our results, taken together with the studies of others, indicate that a complex interaction of cytokines affects granuloma size and that the size and fibrosis of granulomas are to some extent regulated independently.

Detection of rotavirus antigen in tracheal aspirates of infants and children with pneumonia

Clinical manifestations of respiratory tract infection often precede or coincide with rotavirus gastroenteritis in infants and children. To investigate the possible association between respiratory tract manifestations and rotavirus infection, the authors determined human rotavirus (HRV) antigen and respiratory syncytial virus (RSV) antigen in tracheal aspirates of 58 children with clinically diagnosed pneumonia by enzyme-linked immunosorbent assay (ELISA) and immunofluorescent antibody techniques. HRV antigen was detected in 16 out of the 58 cases (27.6%) and RSV antigen was found positive in 27 cases (46.5%). In four cases both HRV and RSV antigens were detected. The results of our study suggest that rotavirus may occasionally by one of the etiologic agents of acute lower respiratory infections of infants and children and that rotavirus infection may be transmitted via respiratory route. However, further extensive studies are needed for confirmation of the association between rotavirus and respiratory tract infection.

Dynamic analysis of splenic Th1 and Th2 lymphocyte functions in mice infected with Schistosoma japonicum

Recent studies indicate that egg granuloma formation in murine Schistosoma mansoni infection is associated with Th2-mediated immune responses. The present study was designed to analyze dynamically the Th1 and Th2 responses in S. japonicum-infected animals and compare them with the results seen with S. mansoni. C3H mice were infected with 10 to 20 cercariae of S. japonicum and sacrificed 3 to 22 weeks later. Spleen cells were stimulated with parasite antigens (egg and adult worm) or the mitogen concanavalin A. Interleukin-2 (IL-2), IL-4, IL-5, and gamma interferon (IFN-gamma) levels were measured in the culture supernatants by enzyme-linked immunosorbent assay (ELISA) or bioassays. Additionally, cytokine-producing cells were enumerated by ELISPOT. The results show that Th2 cytokine production, characterized by IL-4 and IL-5, represents the major response in the first month after egg laying begins, while the Th1 functions of IFN-gamma and IL-2 production are greatly depressed. However, by 22 weeks Th2 responses have diminished and IFN-gamma production in response to concanavalin A is apparent. IL-2 responses are minimal at all times. In vitro depletion of T-cell subsets indicates that CD4+ cells are the major subset responsible for production of IL-5 at 7 weeks of infection. These findings suggest that, as in the case of S. mansoni infection, S. japonicum-induced immunopathology is temporally associated with the host Th2 response, although other experiments indicate that IFN-gamma is also involved.

[Hashimoto's disease with pregnancy]

That normal pregnancy, PIH and Hashimoto's were all closely related with human immunology has been reported by many authors. Six pregnant women with Hasimoto's were studied. Among them four were complicated with PIH, and one with postpartum transient hypothyroidism. MCHA and TGHA were slightly decreased in 2 cases during pregnancy and one congenital hypothyroidism happened among 6 neonates. Our data indicates that pregnancy and Hashimoto's can affect each other.

Association of vanadate-sensitive Mg(2+)-ATPase and shape change in intact red blood cells

Intact human erythrocytes, initially depleted of Mg2+ by EDTA incubation in the presence of A23187, exhibit Mg(2+)-dependent phosphate production of around 1.5 mmol per liter cells.h, half-maximally activated at around 0.4 mM added free Mg2+. This appears to correspond to Mg(2+)-stimulated adenosine triphosphatase (Mg(2+)-ATPase) activity found in isolated membranes, which is known to have a similar activity and affinity for Mg2+. Vanadate (up to 100 microM) inhibited Mg(2+)-dependent phosphate production and ATP breakdown in intact cells. Over a similar concentration range vanadate (3-100 microM) transformed intact cells from normal discocytes to echinocytes within 4-8 h at 37 degrees C, and more rapidly in Mg(2+)-depleted cells. The rate of Ca(2+)-induced echinocytosis was also enhanced in Mg(2+)-depleted cells. These results support previous studies in erythrocyte ghosts suggesting that vanadate-induced shape change is associated with inhibition of Mg(2+)-ATPase activity localized in the plasma membrane of the red blood cell.

Cytochrome b5 and a recombinant protein containing the cytochrome b5 hydrophobic domain spontaneously associate with the plasma membranes of cells

Both cytochrome b5, isolated from rabbit liver microsomes, and LacZ:HP, a recombinant protein consisting of enzymatically active Escherichia coli beta-galactosidase coupled to the C-terminal membrane-anchoring hydrophobic domain of cytochrome b5, were shown to spontaneously associate with the plasma membranes of erythrocytes and 3T3 cells. Association was promoted by low pH values, but proceeded satisfactorily over several hours at physiological pH and temperature. About 150,000 cytochrome b5 molecules or 100,000 LacZ:HP molecules could be associated per erythrocyte. These proteins were not removed from the membrane by extensive washing, even at high ionic strength. After incubation with fluorescently labeled cytochrome b5 or LacZ:HP, cells displayed fluorescent membranes. The lateral mobility of fluorescently labeled cytochrome b5 and LacZ:HP was measured by photo-bleaching techniques. In the plasma membrane of erythrocytes and 3T3 cells, the apparent lateral diffusion coefficient D ranged from 1.0.10(-9) to 8.10(-9) cm2 s-1 with a mobile fraction M between 0.4 and 0.6. The lateral mobility of these proteins closely resembled that reported for lipid-anchored proteins and was much higher than that reported for Band 3, an erythrocyte membrane-spanning protein with a large cytoplasmic domain. These results suggest that the hydrophobic domain of cytochrome b5 could be employed as a universal, laterally mobile membrane anchor to associate a variety of diagnostically and therapeutically useful recombinant proteins with cells.

Biochemical markers associated with the stages of promotion and progression during hepatocarcinogenesis in the rat

Specific biochemical changes occurring during hepatocarcinogenesis have been sought by many investigators. The development of multistage models for hepatocarcinogenesis in the rodent has renewed interest in such marker alterations in preneoplastic as well as neoplastic hepatocytes. Preneoplastic altered hepatic foci (AHF) exhibit specific histomorphologic changes as viewed with tinctorial stains and show a variety of biochemical changes as evidenced by enzyme and immunohistochemistry and by other histochemical markers. During the reversible stage of promotion when AHF are scored by multiple markers, the distribution of markers within these lesions differs with the use of different promoting agents. One interpretation of this finding is that each promoting agent stimulates the replication of a set of initiated cells exhibiting the phenotypic characteristics of a specific programmed phenotype. The same markers score AHF during the stage of progression, but many AHF in this stage are phenotypically heterogeneous, exhibiting in tissue sections a "focus-in-focus" pattern of marker alteration. These latter changes can be correlated with the appearance of karyotypic alterations in preneoplastic hepatocytes. On the other hand, it has been difficult to demonstrate the activation, either mutational or transcriptional, of proto-oncogenes until this stage of progression in rat hepatocarcinogenesis. Thus, a study of biochemical and molecular markers during the stages of hepatocarcinogenesis may lead to a better understanding of potential mechanisms involved in the development of neoplasia through the stages of initiation, promotion, and progression.

An initiation-promotion assay in rat liver as a potential complement to the 2-year carcinogenesis bioassay

Several pharmaceutical agents, manufacturing chemicals, and environmental contaminants were found to act primarily as promoting agents in an initiation-promotion paradigm. The phenotypic distribution of four enzyme markers--placental glutathione-S-transferase (PGST), gamma-glutamyl transpeptidase (GGT), canalicular ATPase (ATPase), and glucose-6-phosphatase (G6Pase)--was analyzed in altered hepatic foci (AHF) by quantitative stereology. The number and volume distribution of AHF were determined for each promoter tested. For phenobarbital and 2,3,7,8-tetrachloro-p-dioxin, PGST and GGT together scored 100% of the AHF; for 1-(phenylazo)-2-naphthol (CI solvent yellow 14) and chlorendic acid, PGST alone marked 90% of the AHF; after chronic administration of WY-14,643, ATP and G6Pase were the predominant markers. In rats fed tamoxifen, G6P scored more than half of the AHF. Differences in the number of AHF promoted by each of these agents and in their phenotypic distributions may reflect the differentially responsive nature of individual initiated hepatocytes to the action of specific promoters. Since the chronic bioassay of suspected carcinogens does not allow one to differentiate between weak complete carcinogens and those carcinogenic agents that act in a reversible manner to promote the growth of previously initiated cells, the partial hepatectomy, altered-hepatic-focus model of cancer development is proposed as a supplement to the chronic bioassay for the identification of those carcinogenic agents that are primarily, if not exclusively, promoting agents in rat liver.

[Analysis of EGFR gene transcription in rat embryo and adult tissues]

EGFR gene transcription in rat embryo and adult tissues were analysed by RNA Northern and Dot hybridization using 2.4 Kb human EGFR cDNA pE 7 as probe. In Northern hybridization (Fig. 1), the normal rat liver RNA showed a major 5.6 Kb RNA band which was a common EGFR mRNA present in human normal and cancer cells. For the comparison of EGFR gene transcription in embryo of different stages and different tissues, the density scanning data of dot hybridization signals are shown as bars in accompanying figures. The results indicated that the highest level of EGFR transcription was seen in rat embryo at 10th to 12th day during neonatal development (Fig. 2 and Fig. 3). In adult rat tissues, EGFR gene was commonly expressed with some variation in different tissues, for example, much more expressed in kidney than in liver, heart, brain and spleen, and moderately expressed in testis and lung (Fig. 4). The EGFR gene transcription could be induced in liver by hepatectomy. Fig. 5 showed the increase of EGFR gene transcripts at the 2-8 th hour of liver regeneration and the decrease after the 8th hour, even reaching a value lower than that of normal liver after the 24th hour. The results suggest that EGFR gene transcripts are commonly present in a wide range of normal tissues and may be involved in the control of proliferation and differentiation in embryo and adult tissues.

DNA damage and repair in gamma-glutamyltranspeptidase-positive and negative hepatocytes in primary culture from carcinogen-treated rats

Chemically induced DNA fragmentation and unscheduled DNA synthesis were determined in gamma-glutamyltranspeptidase (GGT)-positive and GGT-negative hepatocytes isolated from rat livers subjected to a multistage hepatocarcinogenesis regimen (Solt-Farber), which included 0.05% phenobarbital promotion for 6 weeks (early) or 6 months (late). The results indicated that there was DNA damage in untreated GGT-positive and GGT-negative hepatocytes with either period of promotion compared with normal hepatocytes; however, no statistical difference could be seen between GGT-positive and GGT-negative hepatocytes. DNA damage induced in vitro by the activation-dependent carcinogen dimethylnitrosamine was much less in GGT-positive hepatocytes than in GGT-negative hepatocytes or normal hepatocytes. No significant difference in DNA damage was seen in both GGT-positive and GGT-negative cell populations following treatment with the activation-independent carcinogen ethylnitrosourea (ENU), although DNA damage of GGT-positive hepatocytes was less than that of normal hepatocytes. The background of unscheduled DNA synthesis in both GGT-positive and GGT-negative hepatocytes at either time of promotion was higher than that of normal hepatocytes. The capacity for DNA repair in GGT-positive hepatocytes appeared to be lower than that in GGT-negative hepatocytes. GGT-negative hepatocytes exhibited a lower capacity for DNA repair than that of normal hepatocytes in terms of the rate of unscheduled DNA synthesis elicited by dimethylnitrosamine and ethylnitrosourea in vitro.

The effect of carbamylcholine on CFU-s differentiation

The proportion of spleen colony-forming units (CFU-s) killed by hydroxyurea was greatly increased after bone marrow cells (BMCs) from LACA mice were exposed to carbamylcholine (Cach; 1 X 10(-13) to 1 X 10(-9) in vitro and there was a marked change in the proportion of spleen colony types. Following treatment with Cach, granulocytic and mixed erythroid-type colonies increased from 20 to 26.3% and 16.1 to 29.6% in 9-day colonies and from 8.3 to 28.2% and 21.7 to 39.4% in 13-day colonies, respectively. Single cell suspensions of spleen colonies were made for granulocyte-macrophage progenitor (CFU-gm) and late erythroid progenitor (CFU-e) assays. The number of CFU-gm from Cach-treated BMC was about twice that from control BMC for both day 9 and day 13 groups; the number of CFU-e decreased relatively. The results suggest that cholinergic receptors on CFU-s may increase the tendency to differentiate into the granulocytic/monocytic line.

[The clinical significance of antibodies to SM, RNP and SSR polypeptides detected by immunoblotting technique]

Using immunoblotting technique (IBT) antibodies to Sm, RNP and SSB polypeptides we detected in 173 patients with different rheumatic diseases. It was found that antibodies to Sm polypeptides with molecular weights of 28K(B) and 13.5K(D) could be detected almost only in SLE (34.0% and 30.0% respectively). The positive rates of anti-28K and anti-13.5K polypeptides in SLE detected by IBT were significantly higher than those of anti-Sm by counterimmunoelectrophoresis (12.0%) (P less than 0.05). The antibodies to SSB polypeptides with molecular weights of 48K and 43.41K could be detected mainly in Sjogren's syndrome (70.0% and 65.0% respectively) and the antibodies to RNP polypeptides with molecular weights of 68K, 32K(A) and 29K (B') mainly in MCTD (82.6% 100% and 34.8% respectively) (P less than 0.001). It was reported by Pettersson that anti-68K polypeptide had high specificity for the diagnosis of MCTD. But our data showed that the anti-68K polypeptide could also be detected in SLE(26.0%) and PSS(15.0%) and was not so specific for MCTD.

Persistent Ca2(+)-induced activation of erythrocyte membrane Ca2(+)-ATPase unrelated to calpain proteolysis

Preincubation of human erythrocyte membranes with calcium in the submillimolar to millimolar concentration range resulted in an increase of the Ca2+ affinity and apparent maximum velocity of the Ca2(+)-stimulated Mg2(+)-dependent ATPase (Ca2(+)-ATPase). The activation was persistent, as it was not reversed when the Ca2(+)-preincubated membranes were washed with ethylene glycol bis(beta-aminoethyl ether) N,N'-tetraacetic acid-containing buffers. Magnesium was not required for the activation, whereas greater than 2 mM Mg2+ partially antagonized the activation by Ca2+. In some membrane preparations ATP was required in addition to Ca2+ for activation of the Ca2(+)-ATPase, but nonhydrolyzable analogs of ATP had the same effect. Calmodulin prevented the activation by Ca2+ over the same concentration range in which it interacts with the Ca2(+)-ATPase. Taken together the results obtained provided strong evidence that the Ca2+ activation of the enzyme was not due to proteolytic cleavage by endogenous calpain. Thus, activation by Ca2+ was not blocked by leupeptin (100-200 microM), did not require dithiothreitol, and occurred at Ca2+ concentrations greater than those required for activation of calpain I. Furthermore, Ca2+ activation did not result in change in the mobility the native 136-kDa species of the Ca2(+)-ATPase on SDS-gel electrophoresis. Moreover, solubilization of the Ca2(+)-pretreated membranes with Triton X-100 reversed the Ca2+ activation of the Ca2(+)-ATPase. On the other hand, Ca2(+)-pretreatment of the membranes modified the susceptibility of the Ca2(+)-ATPase to both cleavage and activation by exogenously added calpain I. We conclude that pretreatment of Ca2(+)-ATPase in erythrocyte membranes with millimolar Ca2+ activates the enzyme by inducing a persistent conformational change of the enzyme which is, however, subsequently reversed by detergent solubilization.

[Conditioned medium of human nasopharyngeal carcinoma epithelioid cell line CNE 1 contained the activities of transformed growth-inhibiting factor(s)]

The hormone defined serum free conditioned medium (SFCM) of human nasopharyngeal carcinoma epithelioid cell line (CNE 1) was assaied by both the [3H] thymidine incorporation test and the soft agar test. It was found that the SFCM can stimulate the growth of long-term serum free cultured CNE 1 cells in accordence with the fact that the growth rate of long-term serum free cultured CNE 1 cells was directly proportional to the plating density. Alternatively 5% SFCM can inhibit the growth of short-term serum free cultured CNE 1 cells by 51% in which the indicator cell may remained the responsive state of growing in the serum supplemented medium to the effector of interest. Furthermore, SFCM resulted in inhibition of anchorage-independent growth of CNE 1 cells and A431 cells. Also in soft agar test, SFCM can reduce the colony formation of NRK-49F cells in the presence of EGF or EGF plus TGF-beta. These finding suggested that CNE 1 can autocrine growth stimulating factor(s) and growth inhibiting factor(s) in the serum free medium, the latter can strongly reverse malignant phenotypies of CNE 1 and A431 cells in serum supplemented surrounding.