Vascular endothelial growth factor acts as a pericyte mitogen under hypoxic conditions

Angiogenesis is the process by which new vascular networks are formed from preexisting capillaries. The small vessels are composed of two types of cells, namely endothelial cells (EC) and pericytes, with the former being encircled by the latter. We previously showed that hypoxia, the principal cause of angiogenesis, can induce the proliferation of pericytes as well as EC. In this report we present evidence that the hypoxic induction of pericyte growth can be ascribed at least in part to vascular endothelial growth factor (VEGF) produced by this very cell type. First, the finding that hypoxia can stimulate the proliferation of pericytes was confirmed by cultivating bovine retinal pericytes in a controlled-atmosphere culture chamber containing various concentrations of oxygen and then assaying pericyte synthesis of DNA. Second, Northern blot analysis revealed that pericyte levels of mRNA encoding VEGF increased as the atmospheric oxygen tension was decreased; this was accompanied by an increase in de novo synthesis of VEGF proteins. Third, pericytes were able to respond to exogenously added VEGF, resulting in a dose-dependent increase in viable cell numbers. Fourth, polyclonal antibodies against VEGF efficiently blocked the hypoxic induction of pericyte growth. Fifth, pericytes expressed the gene for fms-like tyrosine kinase 1 (flt1) as the predominant form of VEGF receptor, and tyrosine phosphorylation of this receptor protein was enhanced when pericytes were exposed to hypoxia, as it was when cells were exposed to VEGF. Sixth, the antisense DNA complement of flt1 mRNA abolished the hypoxia-induced stimulation of pericyte growth. Finally, exogenous VEGF stimulated the migration of pericytes in a dose-dependent manner. The results thus suggest that VEGF, which has been thought to be a specific mitogen for EC, also acts on neighboring pericytes, probably in both autocrine and paracrine manners, and that the hypoxia-induced overproduction of VEGF could promote not only EC sprouting but also the recruitment of pericytes, thereby contributing to the maturation of newly formed microvessels.

Prognostic factors in severe alcoholic liver injury. Nara Liver Study Group

Severe alcoholic liver injury has been relatively rare, but is gradually increasing in Japan. The clinical features and prognostic factors in severe alcoholic liver injury were retrospectively investigated in 105 patients, consisting of 3 with severe alcoholic hepatitis (SAH), 43 with cirrhosis with superimposed alcoholic hepatitis [liver cirrhosis (LC)+alcoholic hepatitis (AH)], 38 with AH, and 21 with alcoholic cirrhosis. Seven of the 105 patients (6.7%, 2 with SAH and 5 with LC+AH) died of hepatic failure. Patients with SAH showed severe hyperbilirubinemia, reduced hepatic biosynthetic capacity, and marked acute inflammatory reactions, and developed multiple organ failure, such as disseminated intravascular coagulation (DIC), renal failure, acute pancreatitis, or pneumonia. Two SAH patients died within 1 month, whereas five with LC+AH died within 77 days during the second episode of AH. In these nonsurvivors, the serum total bilirubin (T.Bil) level was not normalized, and the hepaplastin test (HPT), serum albumin, cholesterol, and platelet count were not markedly improved after the first episode of AH. In the survivors, elevation of AST lasted longer, and the improvement of T.Bil, hepatic biosynthetic capacity, and the platelet count were much less in patients with LC+AH than in those with AH. Multivariate analysis using the Cox proportional hazards model showed serum C-reactive protein (CRP) and DIC as significant independent prognostic factors among SAH, LC+AH, and AH groups. When factors related to multiple organ failure, such as DIC and renal failure, were excluded, T.Bil and CRP were selected as independent prognostic factors. In patients with LC+AH and AH, CRP, and HPT were shown to be significant independent prognostic factors. These results suggest that SAH with multiple organ failure, and another episode of AH in advanced LC with hyperbilirubinemia and reduced hepatic biosynthetic capacity, are indicative of an extremely poor prognosis in chronic alcoholics.

A novel glycosylphosphatidyl inositol-anchored protein on human leukocytes: a possible role for regulation of neutrophil adherence and migration

We report here a novel glycosylphosphatidyl-inositol (GPI)-anchored glycoprotein on human leukocytes. Treatment of neutrophils with a mAb (3H9) to this molecule sequentially up-regulates and down-regulates beta2 integrin-dependent adhesion of these cells as well as their transendothelial migration in vitro. In addition, this mAb simultaneously modulates the avidity of beta2 integrin for its ligand, iC3b, with kinetics similar to those observed in 3H9 modulation of neutrophil adherence. This mAb also induces beta2 integrin-dependent cytoskeletal remodeling. This novel GPI-anchored protein (GPI-80) is highly homologous with Vanin-1, a recently reported GPI-anchored protein that is expressed on perivascular thymic stromal cells and is involved in thymus homing in mice. The finding that both GPI-80 and Vanin-1 are 40% homologous with human biotinidase suggests the existence of a biotinidase superfamily of molecules that may be involved in the regulation of leukocyte trafficking.

New evidence that the Tyr-157 and Tyr-159 residues of staphylococcal exfoliative toxin B are essential for its toxicity

To determine the active site of exfoliative toxin B (sETB) of Staphylococcus aureus, the etb gene was cloned from an S. aureus SU strain obtained from a patient with impetigo. We prepared a frame shift mutant protein from a recombinant plasmid with a BglII linker inserted into the Tyr-155 codon of the ETB gene (pETB/BglIIL). The recombinant mutant protein (ETB/BglIIL) obtained from Escherichia coli containing pETB/BgIIIL showed no toxicity in neonatal mice and no agglutination activity. The 20-kDa ETB/BglIIL contained 185 amino acid residues. Site-directed mutagenesis was used to introduce mutations at either Tyr-155, Tyr-157, Tyr-159, or Tyr-162. Substitution of any of the Tyr residues decreased exfoliative activity compared with that of native sETB (4,000 EU/ml). Substitution of Tyr-155 with a Phe (ETBYN155) decreased activity 5-fold (800 EU/ml). Substitution of Tyr-157 with Leu (ETB/Y157) decreased activity 80-fold (50 EU/ml) and decreased agglutination titer 5-fold compared with that of native sETB (400,000). Substitution of Tyr-159 with Leu (ETB/Y159)decreased activity 4-fold (1,000 EU/ml). When both Tyr-157 and Tyr-159 were mutated (ETB/Y157-159), both toxicity and antigenicity were completely lost. On an immunodiffusion test, ETBNY157 showed a faint precipitation line, but ETB/BglIIL and ETB/Y157-159 had no activity, showing that the Tyr-157 and Tyr-159 residues are essential for the toxicity and antigenicity of ETB.

Embryonic form of smooth muscle myosin heavy chain (SMemb/MHC-B) in gastrointestinal stromal tumor and interstitial cells of Cajal

Myosin heavy chain (MHC) isoform expression was evaluated by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR) to clarify a possible link between gastrointestinal stromal tumor (GIST) and interstitial cells of Cajal (ICCs) in the gastrointestinal (GI) tract. Using monoclonal antibodies against MHC isoforms, 18 of 27 GISTs (67%) showed immunoreactivity for non-smooth-muscle myosin or the embryonic form of MHC (SMemb), but only one tumor showed immunoreactivity for smooth muscle cell (SMC)-specific isoforms (SM1 and SM2). Co-expression of KIT or CD34, which is also expressed in GIST and ICCs, was demonstrated in 18 (100%) and 16 SMemb-positive tumors (89%), respectively. Otherwise, the expression of SMemb in GIST was not correlated with the patient's age or sex, tumor size, histological grade of GIST, or expression of mesenchymal cell markers, such as alpha-smooth muscle actin (alpha-SMA) or S100 protein. By double-fluorescence immunostaining of the tunica muscularis of the GI tract wall, co-expression of KIT, CD34, and SMemb was demonstrated in ICCs, which were negative for SM1 and SM2. RT-PCR analysis confirmed that GIST expressed SMemb-mRNA, which lacked neuronal cell-specific inserts of 30 bp. These facts further strengthen the current hypothesis that GIST is a tumor of ICCs.

Survival of patient with late onset hepatic failure by living-related liver transplantation from maternal donor with incompatible blood type

A 14-year-old girl with blood type B with late onset hepatic failure (LOHF) of unknown cause has survived through living-related liver transplantation (LRLT). No hepatitis virus, including HAV, HBV, HCV, and HGV, was positive at the onset of LOHF. Autoimmune hepatitis was thought to be the cause because of positive results for serum anti-nuclear antibody at 80 times dilution and elevated gamma-globulin, but treatment with glucocorticoid did not suppress the progressive hepatic failure. Supportive therapy, including pulse therapy with 1g methylprednisolone for 3 days, ursodesoxycholic acid, branched-chain amino acid, and azathioprine did not resolve the hepatic failure. She was treated by repeated plasmapheresis and plasma absorption for 10 months, and then received the left lobe of her mother's liver. (Her mother's blood type was AB). The patient had been well, being treated with tacrolimus and prednisolone, although the serum titer of anti-blood type B antibody was high just after LRLT and mild liver dysfunction continued for more than 3 years after LRLT. Follow-up biopsy 3 years after LRLT revealed chronic hepatitis and progression to liver cirrhosis. Re-transplantation is now under consideration; the patient is now aged 19 years.

Telomerase activity in gastrointestinal stromal tumors

BACKGROUND

Telomerase activity has been observed in 80-90% of carcinomas derived from various organs. However, to the authors' knowledge this report is the first assessment of telomerase activity in gastrointestinal stromal tumors (GISTs).

METHODS

Telomerase activity was analyzed by the telomerase repeat amplification protocol assay in 29 tumors from 26 patients (23 primary tumors from 22 patients, 1 pair of primary and metastatic tumors from 1 patient, and 4 metastatic tumors from 3 patients). Phenotypes, tumor cell proliferation, and overexpression of p53 protein were evaluated immunohistochemically.

RESULTS

Seven of 24 primary tumors (29%) and 5 of 5 metastatic tumors (100%) showed telomerase activity. Telomerase activity positive (+) GISTs were significantly larger (P < 0.05) and showed a significantly higher rate of proliferation than telomerase activity negative (-) tumors (P < 0.0001). All telomerase activity (+) GISTs were classified histologically as high risk tumors. Conversely, 15 of the 17 telomerase (-) GISTs were classified histologically as low risk tumors (P < 0.0001). With regard to p53 immunoreactivity, two and seven telomerase activity (+) tumors showed diffuse and sporadic positivity, respectively, whereas only five telomerase activity (-) tumors showed only focal or sporadic positivity. Telomerase activity was correlated significantly with poor prognosis (P < 0.05) in the patients in whom the primary GISTs were evaluated (n = 23).

CONCLUSIONS

Telomerase activity may be a useful marker for evaluating the malignant potential of GIST. A distinct subgroup of GISTs is a target for therapy with a telomerase inhibitor.

Telomerase activity in gastrointestinal stromal tumors

BACKGROUND

Telomerase activity has been observed in 80-90% of carcinomas derived from various organs. However, to the authors' knowledge this report is the first assessment of telomerase activity in gastrointestinal stromal tumors (GISTs).

METHODS

Telomerase activity was analyzed by the telomerase repeat amplification protocol assay in 29 tumors from 26 patients (23 primary tumors from 22 patients, 1 pair of primary and metastatic tumors from 1 patient, and 4 metastatic tumors from 3 patients). Phenotypes, tumor cell proliferation, and overexpression of p53 protein were evaluated immunohistochemically.

RESULTS

Seven of 24 primary tumors (29%) and 5 of 5 metastatic tumors (100%) showed telomerase activity. Telomerase activity positive (+) GISTs were significantly larger (P < 0.05) and showed a significantly higher rate of proliferation than telomerase activity negative (-) tumors (P < 0.0001). All telomerase activity (+) GISTs were classified histologically as high risk tumors. Conversely, 15 of the 17 telomerase (-) GISTs were classified histologically as low risk tumors (P < 0.0001). With regard to p53 immunoreactivity, two and seven telomerase activity (+) tumors showed diffuse and sporadic positivity, respectively, whereas only five telomerase activity (-) tumors showed only focal or sporadic positivity. Telomerase activity was correlated significantly with poor prognosis (P < 0.05) in the patients in whom the primary GISTs were evaluated (n = 23).

CONCLUSIONS

Telomerase activity may be a useful marker for evaluating the malignant potential of GIST. A distinct subgroup of GISTs is a target for therapy with a telomerase inhibitor.

Increase in memory (CD4+CD29+ and CD4+CD45RO+) T and naive (CD4+CD45RA+) T-cell subpopulations in smokers

To examine the effects of smoking on lymphocyte subpopulations, we measured the following cell subpopulations: CD4+ T-cell subpopulations (i.e., CD4+CD29+, CD4+ CD45RO+, and CD4+CD45RA+ cells); CD8+ T-cell subpopulations (i.e., CD8+CD11a+ and CD8+CD11b+ cells); and natural killer cell subpopulations (i.e., CD16+CD57-, CD16+CD57+, and CD16-CD57+ cells). We measured these subpopulations, together with total CD4+ T, total CD8+ T, total CD3+ T, B (CD19+), and total lymphocytes, in 10 male heavy smokers, 38 male light-to-moderate smokers, and 33 male nonsmokers. The mean ages were 30 y, 31 y, and 32 y, respectively, and ages did not vary significantly among the smokers. CD4+CD29+ and CD4+CD45RO+ (memory T) cells in heavy smokers were significantly more numerous than those in light-to-moderate smokers and nonsmokers. Also, these memory T-cell subpopulations were significantly more numerous in light-to-moderate smokers than in nonsmokers. The number of CD4+CD45RA+ (naive T) cells was significantly larger in heavy smokers than nonsmokers; numbers of CD4+CD45RO+ T and CD4+CD29+ T cells (memory T cells) were significantly correlated with daily cigarette consumption. Numbers of CD3+ T, CD4+ T, CD19+ B, and total lymphocytes in heavy smokers were significantly larger than in nonsmokers. There were significantly more CD3+ T, CD4+ T, and total lymphocytes in light-to-moderate smokers than in nonsmokers. The numbers of CD4+ T lymphocytes in heavy smokers were significantly larger than in light-to-moderate smokers. Perhaps CD4+ T cell subpopulations, especially memory T cells, are most susceptible to the effects of smoking on lymphocyte subpopulations.

Hemolymph ecdysteroid titer and ecdysteroid-dependent developmental events in the last-larval stadium of the silkworm, Bombyx mori: role of low ecdysteroid titer in larval-pupal metamorphosis and a reappraisal of the head critical period

The endocrine regulation of larval-pupal metamorphosis was studied in the silkworm, Bombyx mori, by measuring the following changes: hemolymph ecdysteroid titer, the secretory activity of prothoracic glands and the responsiveness of larvae to ecdysteroids and prothoracicotropic hormone (PTTH), with regard to developmental events such as the occurrence of spinneret pigmentation, initiation of cocoon spinning and onset of wandering stage as indicated by gut purge. These measurements were concentrated especially on the time before and after the head critical period (HCP) which falls 3-4 days before the gut purge ([Sakurai, 1984]). A small increase in the hemolymph ecdysteroid titer was first found during the HCP, and then the titer increased with daily fluctuations. Small but significant titer peaks were found prior to the occurrence of both spinneret pigmentation and gut purge, indicating that an individual titer peak could possess a specific role in development. Responsiveness of larvae to exogenous 20-hydroxyecdysone (20E) after the HCP was markedly higher than that before the HCP. The sensitivity of the prothoracic gland to PTTH also changed during the HCP. The results thus showed that the HCP is not the period after which an additional PTTH release is not required for the developmental events occurring on schedule, but rather it is the period during which complex events occur not only in the endocrine glands but also in the peripheral tissues. In addition, various developmental phenomena before gut purge are brought about by the hemolymph ecdysteroid whose concentration gradually increased with daily fluctuations, and these precise changes in the titer appeared to be important for the sequential occurrence of developmental events in the larval-pupal metamorphosis.

A novel member of the bombyxin gene family: structure and expression of bombyxin G1 gene, an insulin-related peptide gene of the silkmoth Bombyx mori

Bombyxin G1 gene, a novel insulin-related peptide gene of the silkmoth Bombyx mori, has been identified. The G1 gene encodes a precursor peptide which shows 41-56% and 28% sequence identities with preprobombyxins previously characterized and human preproinsulin, respectively. The G1 gene forms a pair with bombyxin C2 gene with opposite transcriptional orientation in a bombyxin gene cluster. The bombyxin G1 mRNA in Bombyx brain was shown to locate in four pairs of medial neurosecretory cells.

Effects of recombinant human bone morphogenetic protein-2 on differentiation of cells isolated from human bone, muscle, and skin

We investigated the effects of recombinant human BMP-2 (rhBMP-2) on differentiation of cells isolated from human bone, muscle, and skin. Cells isolated from bones of six patients (HBM-1 to HBM-6), muscle from five patients (HM-1 to HM-5), and skin from three patients (HF-1 to HF-3) were used. rhBMP-2 had no effects on proliferation of two HBM cells, but had a stimulatory effect on three HM cell samples. rhBMP-2 stimulated both alkaline phosphatase (ALP) activity in all HBM cells and parathyroid hormone (PTH)-dependent cAMP production in three of the four HBM cell samples, although the magnitudes of these stimulatory effects differed among the cells tested. Although none of the HBM cells examined produced detectable amounts of osteocalcin in the absence of 1,25-(OH)2vitamin D3, they synthesized measurable amounts of osteocalcin in its presence. rhBMP-2 inhibited 1,25-(OH)2vitamin D3-dependent osteocalcin production in all of the HBM cell samples. Transplantation of HBM-6 cells with rhBMP-2 using diffusion chambers into the peritoneal cavity of athymic mice induced formation of cartilage and bone in the diffusion chambers, but neither cartilage nor bone was formed in chambers transplanted without rhBMP-2. rhBMP-2 also stimulated ALP activity in all of the HM and HF cell samples examined and PTH-dependent cAMP production in three of four HM cell samples. rhBMP-2 induced no osteocalcin production in any of the HM or HF cells in the presence of 1,25-(OH)2vitamin D3. rhBMP-2 markedly inhibited myotube formation by all of the HM cell samples. Transplantation of HM-4 cells with rhBMP-2, using diffusion chambers, into athymic mice induced ALP-positive cells in the chambers, but neither cartilage nor bone was observed. These results suggest that rhBMP-2 is a potent stimulator of osteoblast differentiation and bone formation in human cells.

Oestradiol regulation of the components of the plasminogen-plasmin system in MDA-MB-231 human breast cancer cells stably expressing the oestrogen receptor

To understand the hormonal regulation of the components of the plasminogen-plasmin system in human breast cancer, we examined the oestradiol (E2) regulation of plasminogen activators (PAs), namely urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1) and uPA receptor (uPAR), in our model system. We used stable transfectants of the MDA-MB-231 human breast cancer cells that express either the wild-type (S30 cells) or the mutant 351asp-->tyr oestrogen receptor (ER) (BC-2 cells). Northern blot analysis showed that there was a concentration-dependent down-regulation of uPA, tPA and PAI-1 mRNAs by E2. In contrast, uPAR mRNA was not modulated by E2. The pure anti-oestrogen ICI 182,780 was able to block E2 action, indicating that the regulation of these genes is ER mediated. The E2 also inhibited the expression and secretion of uPA, tPA and PAI-1 proteins as determined by enzyme-linked immunosorbent assay (ELISA) in cell extracts (CEs) and conditioned media (CM). Zymography of the CM confirmed the inhibitory effect of E2 on uPA activity. Thus, we now report the regulation of uPA, PAI-1 and tPA by E2 in both mRNA and protein levels in ER transfectants. The association between down-regulation of the uPA by E2 and known E2-mediated growth inhibition of these cells was also explored. Our findings indicate that down-regulation of uPA by E2 is an upstream event of inhibitory effects of E2 on growth of these cells as the addition of exogenous uPA did not block the growth inhibition by E2.

Serum substances that interfere with thyroid hormone assays in patients with chronic renal failure

OBJECTIVE

Serum thyroid hormone concentrations in patients with chronic renal failure are usually low, despite normal serum TSH levels. We investigated the effect on thyroid hormone assays of serum dialysable organic acids that are elevated in uraemic patients.

PATIENTS

Serum samples from 42 patients with chronic renal failure who were receiving haemodialysis and 37 sex- and age-matched healthy subjects were examined.

DESIGN AND MEASUREMENTS

Serum thyroid hormone concentrations were measured with an analogue radioimmunoassay (RIA), a labelled antibody assay, and an equilibrium dialysis/RIA method. Serum concentrations of organic acids were determined with high performance liquid chromatography.

RESULTS

Serum thyroid hormone levels determined by an analogue RIA and a labelled antibody assay in uraemic patients increased, and serum concentrations of organic acids decreased following haemodialysis. A significant association existed between serum free T3 (FT3) levels determined by an analogue RIA and serum concentrations of indoxyl sulphate (IS) prior to dialysis. There was also a significant association between serum free T4 (FT4) levels determined by an analogue RIA and serum concentration of IS and hippuric acid (HA) prior to dialysis. There was a significant association between the changes of serum concentrations of indole acetic acid (IAA) and FT4 concentrations prior to and following haemodialysis when determined by an analogue RIA. Serum FT3 and FT4 levels significantly decreased after the addition of IS to serum from healthy subjects when determined by an analogue RIA but not by a labelled antibody assay. Serum FT4 levels, but not FT3 levels, decreased after addition of IAA when determined by an analogue RIA. Serum FT4 concentrations determined by an equilibrium dialysis/RIA were significantly higher than those determined by the other two methods. The addition of IS, IAA, and HA to serum samples from healthy subjects significantly increased FT4 concentrations when determined by an equilibrium dialysis/RIA method.

CONCLUSIONS

Increased serum levels of indoxyl sulphate, indole acetic acid and hippuric acid in sera of uraemic patients may interfere with thyroid hormone measurements when an analogue radioimmunoassay is used. In contrast, there was little Interference with a labelled antibody assay. Dialysable organic acids may also interfere with thyroid hormone assays determined by an equilibrium dialysis/radioimmunoassay method.

Health effects of indoor fluoride pollution from coal burning in China

The combustion of high fluoride-content coal as an energy resource for heating, cooking, and food drying is a major exhaust emission source of suspended particulate matter and fluoride. High concentrations of these pollutants have been observed in indoor air of coal-burning families in some rural areas in China. Because airborne fluoride has serious toxicological properties, fluoride pollution in indoor air and the prevalence of fluorosis have been analyzed in a fluorosis area and a healthy nonfluorosis area in China and in a rural area in Japan. For human health, fluoride in indoor air has not only been directly inhaled by residents but also has been absorbed in stored food such as corn, chilies, and potatoes. In the fluorosis area in China, concentrations of urinary fluoride in the residents have been much higher than in the nonfluorosis area in China and in the rural area in Japan. In the fluorosis area, almost all elementary and junior high school students 10-15 years of age had dental fluorosis. Osteosclerosis in the skeletal fluorosis patients was very serious. Urinary deoxypyridinoline in rural residents in China was much higher than in rural residents in Japan. Data suggest that bone resorption was extremely stimulated in the residents in China and that fluoride may stimulate both bone resorption and bone formation. Because indoor fluoride from combustion of coal is easily absorbed in stored food and because food consumption is a main source of fluoride exposure, it is necessary to reduce airborne fluoride and food contamination to prevent serious fluorosis in China.

Ovalbumin coupled either with murine red blood cells or liposome induces IgG but not IgE antibody production

Ovalbumin (OVA) was coupled with murine red blood cells (MRBC) using glutaraldehyde. The OVA-MRBC conjugate induced anti-OVA IgG antibody in mice at almost the same level as OVA in alum. However, no IgE antibody production specific for OVA was observed in OVA-MRBC-injected mice. A significant increase in IGG2a production was obtained with OVA-MRBC immunization, whereas the production of IgG1 predominated in OVA in alum immunization. Am OVA-liposome conjugate induced IgE-specific unresponsiveness in mice in the same manner as OVA-MRBC. Similar results were obtained when antigens other than OVA, such as tetanus toxoid or diphtheria toxoid, were coupled to liposome. These results show the potential of antigen-liposome conjugates for the development of vaccine that induces sufficient IgG antibody production without IgE synthesis.

Soluble form of selectins in blood of patients with acute myocardial infarction and coronary intervention

Soluble (s) P-selectin, sE-selectin, sL-selectin and soluble intercellular adhesion molecule-1 (sICAM-1) levels were examined by monoclonal antibody-based enzyme immunoassay on serum samples taken from nine patients with acute myocardial infarction (AMI) and eight patients with stable angina pectoris (SAP) before and after the successful percutaneous transluminal coronary angioplasty (PTCA). In patients with acute phase of AMI, the levels (mean +/- SEM) of sP-selectin (110 +/- 18 ng/ml) and sE-selectin (54 +/- 15 ng/ml) before PTCA, were significantly higher than those in the SAP group, the values being 44 +/ 27 and 21 +/- 4 ng/ml (p < 0.05), respectively. After recanalization, the levels of sE-selectin and sL-selectin were significantly decreased (sE-selectin 54 +/- 15 to 42 +/- 11 ng/ml, sL-selectin 1104 +/- 106 to 891 +/- 59 ng/ml, P < 0.05, respectively). These findings suggest that the presence of activated and/or injured endothelial cells, which may be involved in the plaque disruption or intraluminal thrombosis in AMI region and that the inflammatory process may be altered after reperfusion therapy.

[Effects of antihypertensive treatment on the thickening of the basal portion of the interventricular septum in essential hypertension]

Previous echocardiographic studies have indicated that the basal portion of interventricular septum is locally thickened in many patients with essential hypertension. This retrospective study investigated whether this localized thickening is decreased by antihypertensive treatment. Twenty-four patients with mild essential hypertension (15 males, 9 females, mean [+/- SD] 55 +/- 9 years) were selected who had local thickening at the basal portion of interventricular septum (> or = 11 mm) on echocardiograms recorded within 3 months after the first visit and were followed up by echocardiography 6 months or more after the start of antihypertensive treatment. Interventricular septal wall thickness at the mid portion (IVST), posterior wall thickness (PWT), left ventricular mass index (LVMI), aorto-septal angle, blood flow velocity in left ventricular outflow tract, and the thickness of the basal portion of interventricular septum (septal wall maximum thickness within 1.5 cm apex side from the joint of interventricular septum and aorta in the long-axis view of B-mode echocardiograms) were measured. Blood pressure was significantly decreased from 152.7 +/- 8.7/93.1 +/- 8.0 mmHg to 140.0 +/- 8.2/86.6 +/- 8.2 mmHg by treatment (p < 0.0001). The thickness of the basal interventricular septum was significantly reduced by treatment from 12.3 +/- 1.7 mm to 10.3 +/- 1.4 mm (p < 0.0001). Mean IVST, PWT and LVMI were slightly reduced by treatment, but the differences were not statistically significant. These results suggest that the thickening of basal interventricular septum is induced by high blood pressure, and the measurement of the thickness of basal interventricular septum might be a useful tool to estimate and monitor the effect of antihypertensive treatment in patients with mild essential hypertension.

Inhibition of tumor cell growth by murine splenic adherent cells stimulated with IFN-gamma

We have previously reported that the growth of lymphocytes and tumor cells with lymphocyte lineage was strongly inhibited by a part of cloned macrophage hybridomas. This growth inhibition was accomplished by cell-to-cell contact and found to be attributed to lipid-like molecule(s) in a macrophage hybridoma cell membrane fraction. Instead of macrophage hybridomas, in the present study we utilized splenic adherent cells (SACs) that had been stimulated with IFN-gamma to see whether they inhibited tumor cell growth or not. The results demonstrated that IFN-gamma-stimulated but not unstimulated SACs showed a significant growth inhibition of BW-5147 tumor cells. This growth inhibition was not mainly mediated by prostaglandin E2 secreted from macrophages, since the inhibition was not reduced in the presence of indomethacin. Furthermore, as was reported previously in the case of macrophage hybridomas, the inhibitory activity resides in a lipid fraction of IFN-gamma-stimulated SAC membrane.

Increase in the helper inducer (CD4+CD29+) T lymphocytes in smokers

Previously, we reported an increase in the number of CD4+ T lymphocytes in the peripheral blood of smokers. In the present study, subpopulations of CD4+ T lymphocytes together with CD8+ T lymphocytes, total (CD3+) T lymphocytes, B (CD19+) lymphocytes, natural killer (CD16+) cells and total lymphocytes were examined by two-color staining using anti-2H4 (CD45RA) and anti-4B4 (CD29) monoclonal antibodies in 8 male smokers and 22 age-matched male non-smokers. The number of CD4+CD29+ T lymphocytes in smokers was significantly higher than that in non-smokers. The total number of CD4+ T lymphocytes in smokers was also significantly higher. No significant differences in CD8+ T, CD19+ B lymphocytes and CD16+ NK cells were found between smokers and non-smokers. Thus, it is suggested that the increase in the number of CD4+CD29+ (helper inducer) T lymphocytes is responsible for the increase in total CD4+ T lymphocytes in smokers.

Changes in T cell subpopulations in lead workers

To investigate the effects of lead on the human immune system, we analyzed T cell subpopulations and B (CD19+) cells in peripheral blood in 71 male lead workers. They were engaged in manufacturing lead stearate in a chemical factory, aged 20 to 74 (mean 48) years. Their blood lead concentrations (PbB) were between 7 and 50 (mean 19) micrograms/dl. The control group consisted of 28 "healthy" male volunteers without a history of occupational exposure to lead or other hazardous substances, aged 33 to 67 (mean 55) years. In comparison with the controls, a significant reduction in the number of CD3+CD45RO+ (memory T) cells and a significant expansion in the percentage of CD8+ cells in the lead workers were found. There was a significant positive correlation between the percentage of CD3+CD45RA+ (naive T) cells and PbB in the lead workers. It is suggested that CD45RO+ memory T cells may be most susceptible to the effects of lead on T cell subpopulations.

Changes of telomere length in children after hematopoietic stem cell transplantation

Telomeres are responsible for keeping the stability not only of chromosomes but also of genes. To investigate the effect of hematopoietic stem cell transplantation (HSCT) on telomeres, we studied telomere length in the peripheral blood mononuclear cells of 31 children who received HSCT. In the auto-HSCT groups telomere length ranged from 8.6 to 12.0 kb and in the allo-HSCT groups from 8.4 to 12.0 kb. Comparison of the telomere length between before and after auto-HSCT showed shorting up to 1.0 kb. Moreover, comparison between donors and recipients in allo-HSCT revealed that telomeres of recipients were up to 1.0 kb shorter than those of the donors. Patients who received allo-HSCT from donors older than 18 years had significantly shorter telomeres than those transplanted from donors under 18 years old (P < 0.05), indicating that donor age is an important factor for recipient's telomere length. These findings suggest that the effects which might be induced by shortening of telomeres in recipients are within the biologically tolerable range. However, if hematopoietic stem cells from elderly donors are transplanted into younger patients, the telomere length may become too short for acceptable lifetime risks of genetic instability in the recipient.