Functional characteristics of the intercellular adhesion molecule-1 (CD54) expressed on cytotoxic human blood lymphocytes

We have shown that intercellular adhesion molecule-1 (ICAM-1) (CD54) positive cells are mainly responsible for the natural cytotoxic function of human blood lymphocytes. The evidences were the inhibition of cytotoxicity by anti-ICAM-1 (LB-2) monoclonal antibodies (mAb) and the loss of lytic activity after removal of the ICAM-1+ cells. In addition, the cytotoxic potential of the separated ICAM-1- lymphocyte population after activation appeared in parallel with the expression of this molecule. The ICAM-1+ lymphocytes lysed both LFA-1 (CD11a/CD18 or Leu-CAMa) positive and negative cell lines, and pretreatment of the effectors with the LB-2 mAb also inhibited the lysis of LFA-1- targets. The results point to a yet unrecognized role of ICAM-1 on the lymphocytes. Kinetics experiments suggested that pretreatment of lymphocytes with alpha-ICAM-1 (LB-2) mAb did not inhibit the promptly established lytic interactions but influenced later events, recycling and/or recruitment of effectors. It is possible that the cytotoxic potential is regulated by contacts between the members of the lymphocyte population and that these events occur via their ICAM-1 and LFA-1. Exposure of lymphocytes to NK-sensitive targets for 16 hr elevated their cytotoxic potential. The function of activated lymphocytes was not inhibited by the LB-2 mAb.

Hemorrhage produces depression in microvascular blood flow which persists despite fluid resuscitation

Although various hemodynamic changes occur during and following hemorrhagic shock, the progressive changes in microvascular blood flow (MBF) in various organs under those conditions have not been determined. To study this, non-heparinized rats were bled to and maintained at a mean arterial pressure of 40 mm Hg until 40% o the shed blood volume was returned in the form of Ringer's lactate (RL). The rats were then resuscitated with 2, 3, or 4 times (x) the volume of maximum bleedout with RL. Laser Doppler flowmetry (LDF) was used to determine the MBF in the liver, kidney, spleen, skeletal muscle, and small intestine at different intervals following hemorrhage and resuscitation. The results indicate that MBF was significantly decreased during hemorrhage and remained depressed 30-240 min post-resuscitation in all the measured organs. This was not due to the decreased hematocrit since acute hemodilution did not significantly depress MBF. These results indicate that 1) LDF is a useful technique for repeated assessment of MBF following hemorrhage and resuscitation; 2) resuscitation with 4x RL increased central venous pressure to more than twice the normal value but did not restore or maintain MBF, suggesting that pharmacological support may be needed under such conditions; 3) the lack of maintenance of MBF following hemorrhage and resuscitation may form the basis of multiple organ failure observed following severe and prolonged hemorrhagic shock.

Low-molecular-weight GTP-binding proteins serving as ADP-ribosylation substrate for ADP-ribosyltransferase from Clostridium botulinum and their relation to phosphoinositides metabolism in thymocytes

ADP-ribosyltransferase from Clostridium botulinum type C strain was found to induce an increase of inositol phosphates (IPs) formation in murine thymocytes membranes. Incubation of electropermeabilized murine thymocytes with the enzyme also caused an increase of IPs formation in the cells. This increase of IPs formation in the enzyme-treated membranes and electropermeabilized cells was dependent on the amount of both NAD and the enzyme, suggesting that the stimulation of phosphoinositide-specific phospholipase C (PLC) was related to ADP-ribosylation of membrane proteins by the enzyme. On the other hand, in calf and murine thymocytes two proteins with the same molecular weight of 21,000 were found to be ADP-ribosylated by the botulinum ADP-ribosyltransferase. A minor ADP-ribosylation substrate was shown by two-dimensional polyacrylamide gel electrophoresis to be G21k, a low-molecular-weight GTP-binding protein (G protein) suggested previously by us to be involved in PLC regulation [Wang, P. et al. (1987) J. Biochem. 102, 1275-1287; (1988) 103, 137-142; and (1989) 105, 461-466], and the other major ADP-ribosylation substrate was identified as a rho A protein. Under the experimental conditions of the IPs formation study, ADP-ribosylation of both G21k and rho A proteins by botulinum ADP-ribosyltransferase in membranes and permeabilized cells was observed. These results suggest that botulinum ADP-ribosyltransferase-induced PLC stimulation in thymocytes is closely correlated with ADP-ribosylation of the low-molecular-weight G proteins.

Energy storage in quantum-well lasers

A new scheme of energy storage in single-quantum-well semiconductor lasers is analyzed. This scheme involves the storage of the majority of injected carriers in the continuum states of the surrounding bulk material, in which the carrier density is diluted and the higher-order carrier-density-dependent recombination processes are much smaller. This allows the inversion level to build up to a much higher level during the pumping stage of Q switching. The possibility of using indirect-band-gap semiconductors for carrier storage is also proposed.

Purification and partial amino acid sequences of phosphoinositide-specific phospholipase C of Drosophila eye

To examine whether the norpA (no receptor potential A) gene encodes a phosphoinositide-specific phospholipase C (PLC) in the eye of Drosophila, a major PLC in the extract from normal Drosophila heads, which was absent in the extract from norpA mutant heads, and purified and its partial amino acid sequences were determined. The purification of the major PLC in KCl extract from normal Drosophila heads was achieved by sequential column chromatography on DEAE-Sepharose CL-6B, Mono Q, Superose 12, Mono S, second Mono S, and second Mono Q, followed by column chromatography on Superose 12 in the presence of 1% sodium cholate. The enzyme thus purified was found to be homogeneous on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular weight of the enzyme was estimated to be 98,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme hydrolyzed both phosphatidylinositol (PI) and phosphatidylinositol 4,5-bisphosphate (PIP2). Interestingly, the calcium and pH requirements for activation of the crude enzyme (KCl extract) were quite different from those of partially purified enzyme (active fraction from second Mono Q column). The maximal activity for PIP2 hydrolysis was observed at calcium concentrations between 10(-7) and 10(-5) M for both the crude and partially purified enzymes. On the other hand, the activity for PI hydrolysis of the crude enzyme increased with increasing calcium concentrations, while that of the partially purified enzyme reached a maximum at calcium concentrations between 10(-6) and 10(-4) M, and decreased at millimollar concentration. The pH dependences for PI hydrolysis of the crude enzyme and the partially purified enzyme were similar. The crude enzyme hydrolyzed PIP2 over a broad pH range from 6 to 8.5, while the activity of the partially purified enzyme monotonously increased with increasing pH. The partial amino acid sequences were determined by treating the purified enzyme with endopeptidase Lys-C; the resultant peptide fragments were purified on a high performance liquid chromatography-reverse phase column and then sequenced with sequencer. The obtained sequences were found to be a part of the deduced amino acid sequences of cDNA which was suggested to be norpA gene.

Effectiveness of phenol-atabrine-paste (PAP) instillation for female sterilization

Two groups of sterilized women, 3307 by phenol-atabrine-paste (PAP) instillation and 1026 by mini-lap technique, were follow-up interviewed to determine their relative effectiveness. PAP, if successfully performed, was as effective as the mini-lap. The life table pregnancy rates among successful PAP women were 0.21 and 0.28 at 12 and 24 months, respectively. The rates among the unsuccessful PAP women, however, were high: 15.1 and 30.5 at 12 and 24 months, respectively. In spite of its distinctive advantage of being non-surgical, wider promotion of PAP sterilization procedure deserves caution.

Preheparinization improves organ function after hemorrhage and resuscitation

Recent studies indicate that heparinization before hemorrhage maintains microvascular patency in the liver and kidney during and after severe hemorrhagic shock. However, it is not known whether preheparinization has any protective effects on organ function after hemorrhage and resuscitation. To study this, unanesthetized rats (with or without preheparinization) were bled to and maintained at a mean arterial pressure of 40 mmHg until 40% of the maximum shed blood volume was returned in the form of Ringer lactate (RL). They were then resuscitated with four times the volume of the shed blood with RL. Cardiac output (CO), [3H]inulin clearance (CIn; renal function), hepatic microvascular blood flow (HMBF), and hepatocellular function (HF), i.e., maximal velocity of indocyanine green clearance (Vmax), were determined 1.5 h after resuscitation. Although CO decreased in both groups, the values in preheparinized rats were significantly higher than in the nonheparinized rats. The improvement in CIn as well as HMBF followed the same trends. HF (Vmax) was significantly depressed in the nonheparinized rats but was maintained in preheparinized rats. Thus administration of heparin before the onset of hemorrhage improves CO and renal function and restores HF to control after hemorrhage and resuscitation. These protective effects of preheparinization could be due to the maintenance of microvascular patency and prevention of blood sludging during and after hemorrhage.

Hepatocellular dysfunction occurs early after hemorrhage and persists despite fluid resuscitation

The liver is a major organ involved in multiple organ failure (MOF) following hemorrhage and trauma. However, it is not known if active hepatocellular membrane transport, measured by in vivo indocyanine green (ICG) clearance, is depressed after hemorrhage and if it persists after resuscitation. To study this, rats were bled to and maintained at a mean BP of 40 mm Hg until 40% of maximum bleedout (MB) volume was returned in the form of Ringer's lactate (RL). The rats were then resuscitated with 2X or 3X the volume of MB with RL and hepatocellular function was determined at various intervals. ICG, two to four doses (0.167-1.667 mg/kg BW), was given intravenously and [ICG] was continuously recorded without the need of blood sampling, using an in vivo hemoreflectometer with computer-assisted data acquisition. Initial velocity of clearance (V0) was calculated from [ICG] vs time (t) according to [ICG] = e (a + bt + ct 2), where eab is V0. Maximal velocity of clearance (Vmax) and Km, a kinetic constant representing the efficiency of the active transport process, were determined from the Lineweaver-Burk plot. The results indicate that Vmax decreased by 66% at MB and remained depressed despite fluid resuscitation. Km, decreased by 58% at MB, returned to prehemorrhage level after 3X RL but was not maintained and it decreased by 60% at 4 hr after resuscitation. This in vivo study demonstrates that active hepatocellular function is significantly depressed early after hemorrhage and persists despite resuscitation with RL and may form the basis of the MOF observed after severe and prolonged hemorrhage.

[Clinical-chemical testing on admission to Odense Hospital]

The use of laboratory screening on admission (i.e. laboratory tests which are always requested on admission of all of the patients to the department) was investigated at Odense University Hospital. Nursing sisters were interviewed about the current practices at their departments and consultants replied to a questionnaire about their attitudes to laboratory screening on admission. Screening on admission consisted of from 0 to 24 analyses. 90% of the consultants considered that screening on admission saved time, 60% that it might reveal other diseases, 52% that it could be used as a status on control admissions and 79% that it was suitable in the preparation for operation and invasive diagnostic procedures. On the basis of a survey of the literature, it is concluded that routine use of laboratory screening on admission is not justified.

Phorbol myristate acetate-induced down-modulation of CD4 is dependent on calmodulin and intracellular calcium

PMA causes rapid down-modulation of CD4 molecules on murine immature thymocytes, human PBL, and CD4-positive human tumor cell lines, but not on murine peripheral lymphocytes. The mechanisms of phorbol ester-induced down modulation of CD4 molecules, however, have not been elucidated. To determine how PMA down-modulates CD4 expression by T lymphocytes, we studied the ability of inhibitors of protein kinase C, calmodulin, actin, and tubulin to block PMA-induced modulation of CD4 in several murine and human cell types. We also tested the ability of intracellular and extracellular calcium chelators to block CD4 internalization. There was marked variability in the degree of PMA-induced down-modulation of CD4 among various cell types. The effects of PMA on CD4 expression were greater for murine thymocytes, for human PBL, and for the human lymphoblastic leukemia cell line, MOLT-3, than for any of the other cell types studied. The protein kinase C inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine, blocked phosphorylation but not internalization of CD4 molecules induced by PMA. Therefore, phosphorylation of CD4 molecules by protein kinase C is not required for the internalization of the molecules. Internalization was blocked by both inhibitors of calmodulin, N-(6-aminohexyl)-5-chloro-1-naphthalene-sulfonamide, and trifluoperazine. PMA-induced internalization of CD4 was blocked by Quin-2 AM, which chelates intracellular calcium. EGTA, which chelates extracellular calcium, did not block internalization. Inhibitors of actin or tubulin did not block internalization. These results suggest that PMA-induced modulation of CD4 can occur in the absence of phosphorylation of the CD4 molecules and is calmodulin and intracellular calcium dependent.

Phorbol myristate acetate-induced down-modulation of CD4 is dependent on calmodulin and intracellular calcium

PMA causes rapid down-modulation of CD4 molecules on murine immature thymocytes, human PBL, and CD4-positive human tumor cell lines, but not on murine peripheral lymphocytes. The mechanisms of phorbol ester-induced down modulation of CD4 molecules, however, have not been elucidated. To determine how PMA down-modulates CD4 expression by T lymphocytes, we studied the ability of inhibitors of protein kinase C, calmodulin, actin, and tubulin to block PMA-induced modulation of CD4 in several murine and human cell types. We also tested the ability of intracellular and extracellular calcium chelators to block CD4 internalization. There was marked variability in the degree of PMA-induced down-modulation of CD4 among various cell types. The effects of PMA on CD4 expression were greater for murine thymocytes, for human PBL, and for the human lymphoblastic leukemia cell line, MOLT-3, than for any of the other cell types studied. The protein kinase C inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine, blocked phosphorylation but not internalization of CD4 molecules induced by PMA. Therefore, phosphorylation of CD4 molecules by protein kinase C is not required for the internalization of the molecules. Internalization was blocked by both inhibitors of calmodulin, N-(6-aminohexyl)-5-chloro-1-naphthalene-sulfonamide, and trifluoperazine. PMA-induced internalization of CD4 was blocked by Quin-2 AM, which chelates intracellular calcium. EGTA, which chelates extracellular calcium, did not block internalization. Inhibitors of actin or tubulin did not block internalization. These results suggest that PMA-induced modulation of CD4 can occur in the absence of phosphorylation of the CD4 molecules and is calmodulin and intracellular calcium dependent.

Expression of the adhesion molecule ICAM-1 and major histocompatibility complex class I antigens on human tumor cells is required for their interaction with autologous lymphocytes in vitro

In a group of 30 human tumors, comprising 12 lung, 14 ovarian, 2 breast carcinomas, 1 hypernephroma and 1 mid-gut carcinoid, the expression of major histocompatibility complex (MHC) class I molecules and the intercellular adhesion molecule 1 (CAM-1, CD54) was found to vary independently. Some tumors expressed both or neither of these molecules. Among 9/13 ICAM-1+ tumors, in which greater than 50% cells reacted with the anti-ICAM-1 monoclonal antibody (mAb) (LB-2), the class I antigen was also detected on greater than 50% of the cells. Only 2 ICAM-1+ tumors were class-I-. In 5/17 cases the tumors were MHC-class-I+ and ICAM-1-. Lymphocytes collected from the blood or from the tumor site were assayed for recognition on the tumor cells in the auto-tumor cytotoxicity test and in mixed lymphocyte tumor cell culture (MLTC). Positive results were obtained only with the MHC-class-I+/ICAM-1+ tumors. In vitro treatment of the tumor cell suspensions with interferon gamma and tumor necrosis factor alpha (TNF alpha) induced or enhanced the ICAM-1 and/or class I antigen expression in 8/12 cases. Of the tumor samples treatged, 8/9 acquired stimulatory capacity and 3/10 became susceptible to lysis by the lymphocytes. In 6/6 MLTC performed with the cytokine-treated tumor cells, cytotoxicity against the autologous tumor was generated. Three of these MLTC lymphocytes also lysed the untreated targets. mAb directed to class I antigens or to ICAM-1 inhibited both the stimulation by and the lysis of tumor cells when confronted with fresh lymphocytes. The cytotoxicity generated in the MLTC was also inhibited. If, however, the cytotoxic function was induced in MTLC containing interleukin-2 (5 U/ml), inhibition was obtained only by pretreatment of the targets with mAb against ICAM-1. The results show thus (a) that the lymphocytes react in vitro with tumor cells only if these express both MHC class I molecules and ICAM-1; (b) that expression of these molecules can be induced by interferon alpha and TNF alpha; (c) that cytotoxic effectors generated in the MLTC with cytokine-treated tumors can also act on the untreated tumor cells. The requirement of the two surface moieties for the interaction with lymphocytes was also substantiated by blockade with relevant mAb.

[Myelopathy and radiculopathy in diffuse idiopathic skeletal hyperostosis]

Thirty-four patients of diffuse idiopathic skeletal hyperostosis (DISH) were presented. Twenty-four of them were associated with myelopathy or radiculopathy, mainly due to spinal stenosis. Plain X-ray films showed there was spinal flowing or laminated ossification on the anterior or right lateral side, forming continuous bony bridge at least of four vertebral bodies. Ossification occurred both on the spinal and extra-spinal region. Operative findings of 11 cases revealed significant encroachment of the ossified mass on the dural sac, especially at the level of the apophyseal joint. OPLL was found in ten cases. DISH and OPLL may be different manifestations of same entity. In this series, there was not enough evidence of diabetes mellitus related to DISH, and no specific antigen in HLA typing.

Quantitative digital subtraction arteriography with a calibration catheter

Quantitative intraarterial digital subtraction arteriography (DSA) was performed using a calibration catheter with three distal metallic ring markers. The two outer markers were 50 mm apart, and the third marker was in the middle. Measurements of 54 vessel diameters of the abdominal aorta, renal, lumbar, and iliac arteries were performed in a comparison study with direct film arteriograms in 10 aortofemoral runoff studies. Diameter measurements were made by both the observer on hard copy DSA images and by a computer using modified semiquantitative software. Against measurements on film, which were used as the standard, deviation in measurement on digital images varied from 8 to 13% for arterial diameters less than 5 mm and from 2 to 6% for diameters greater than or equal to 5 mm. Projectional artifacts caused 3% or less error. Knowing these variations in measurement is important in order to determine error tolerances for clinical applications. The calibration catheter serves as a convenient internal marker for DSA.

Antileukemic effect of low-dose harringtonine

The effect of harringtonine (HA) in various concentrations on HL-60 was evaluated. 0.10 microgram/ml HA showed a strong cell killing effect, and 0.025 microgram/ml HA a weak differentiation induction accompanied by cell growth retardation. Differentiation induction did not occur in 5 other human leukemic cell lines. We consider that antileukemic effect of HA is cytotoxicity, not differentiation induction.

51Cr-EDTA: a marker of early intestinal rejection in the rat

Intestinal permeability was studied after accessory intestinal transplantation in Lewis rats. Five groups were evaluated: Group 1--isografts (N = 6); Group 2--Lewis X Brown Norway F1 (LBN-F1) allografts (N = 6); Group 3--isografts treated with CsA 2 mg/kg/day X 10 days (N = 6); Group 4--LBN-F1 allografts treated with CsA 2 mg/kg/day X 10 days (N = 6); Group 5--LBN-F1 allografts treated with CsA 4 mg/kg/day X 28 days (N = 6). Chromium-labeled ethylenedimianetetraacetate (51Cr-EDTA) was given through the proximal stoma of the graft. Renal clearance of 51Cr-EDTA and mucosal biopsies were followed post-transplant. The biopsies of the intestinal graft showed no rejection in Groups 1, 3, and 5; fulminant rejection in Group 2; and mild atypical rejection in Group 4. 51Cr-EDTA clearance was elevated in all groups during the first 7 days post-transplant. Thereafter, 51Cr-EDTA excretion fell to lower levels in the animals with histologically normal grafts (Groups 1, 3, and 5). 51Cr-EDTA excretion in Group 4 was increased with the first histological evidence of rejection on Day 14 and remained elevated until sacrifice (P less than 0.02 compared to Groups 3 and 5). A transient permeability defect occurs after intestinal grafting. Once the graft has recovered from this injury, 51Cr-EDTA is a sensitive marker for intestinal rejection.

[Effects of complex of 3,6-di-(dimethylamino)-dibenzopyriodonium with praseodymium dicitrate on the syntheses of DNA, RNA, protein, nucleoprotein and ATP of leukemia L 7712 cells in mice]

The incorporations of [3H] thymidine, [3H]uridine and [3H]leucine into DNA, RNA and protein synthesis in leukemia 7712 cells were inhibited by the complex of 3,6-di-(dimethylamino)-dibenzopyriodonium with praseodymium (Pr, rare earth element) dicitrite 34 micrograms/ml for 3-24 h. The degree of inhibition increased in proportion to the incubation time. After being treated with [C17H20N2I]3[Pr(C6H5O7)2] 34 micrograms/ml for 3, 6, 12 and 24 h, the incorporation of [32P]Na2HPO4 into the nucleoprotein of leukemia 7712 cells was inhibited by 49, 57, 65 and 85%, while those into ATP were inhibited by 43, 59, 65 and 83%, respectively. The ID50 of [C17H20N2I]3[Pr(C6H5O7)2] on DNA synthesis in leukemia 7712 cells at 24 h was 22 micrograms/ml. After the complex was removed from the medium entirely, the rate of DNA synthesis decreased with time over 3-12 h. This result indicated that the inhibition mechanism was likely due to damage to the DNA template.