Heterogeneous effects of exogenous IL-2 on HIV-specific cell-mediated immunity (CMI). A characteristic feature associated with HIV-1 infection of the human host is a chronic decline in circulating CD4+ T helper/inducer cell numbers. Impaired cell-mediated immune functions usually occur in parallel with the decline in CD4+ T cells. Activated CD4+ T helper cells are a major source of endogenous IL-2 which is required for the immunoregulation of both antigen-specific B cells and CD8+ T cells. HIV-specific T cell proliferative responses are said to be weak and inconsistent, even during the asymptomatic phase of disease. We thus wished to determine how exogenous IL-2 affected HIV-specific T cell proliferation at different stages of the disease. Our cohort of 81 included both asymptomatic and symptomatic HIV-infected patients as well as uninfected normal donors. Proliferative responses of peripheral blood mononuclear cells (PBMC) that were elicited during culture with an immunodominant gp41-derived synthetic peptide, gp41[8], and which were known to be CD8+ cell-associated in asymptomatics only, were used to analyse the effects of exogenous IL-2. IL-2 had three main effects on HIV-specific proliferation, namely (i) an additive effect, (ii) a synergistic effect, and (iii) an induced effect. More specifically, low dose exogenous IL-2 frequently augmented lymphoproliferation in both asymptomatic and symptomatic gp41[8] responders. In most symptomatics, however, who were predominantly gp41[8] non-responders, exogenous IL-2 induced lymphoproliferation. Flow cytometric analyses using dual immunofluorescence were used to analyse the T cell subset distribution of proliferating PBMC cultures. During culture with gp41[8], both CD4+ and CD8+ T cell numbers increased. However, after the addition of exogenous IL-2 to gp41[8]-containing cultures, CD8+ cell-associated lymphoproliferative responses were preferentially augmented. These results suggest that in symptomatics there is an inadequate supply of endogenous IL-2 to help maintain the strong and effective CD8+ cell-associated anti-viral immunity, and an exogenous supply of IL-2 may be required.


Tumour necrosis factor enhances the asbestos-induced production of reactive oxygen metabolites by human polymorphonuclear leucocytes (PMN). We studied the effect of recombinant tumour necrosis factor-alpha (TNF-alpha) on the production of reactive oxygen metabolites (ROM) by human PMN exposed in vitro to chrysotile and crocidolite asbestos fibres, quartz dusts and opsonized zymosan. TNF caused a significant increase in ROM release by PMN, and significantly and dose-dependently amplified the ROM production induced by asbestos fibres. The amplification of ROM production by TNF can be of crucial importance in the process of lung inflammation and fibrogenesis in pneumoconioses.


Endothelial cell damage in primary biliary cirrhosis: influence of cholestasis and immunological mechanisms. In a study looking for evidence of endothelial cell damage in primary biliary cirrhosis, serum from patients was found to be significantly more cytotoxic to cultured endothelial cells in vitro than normal control serum (P less than 0.001). Serum also contained higher levels of von Willebrand factor antigen (vWFAg, a specific product of the endothelium) than control serum (P less than 0.001). Cytotoxicity correlated with serum levels of vWFAg (P less than 0.05) and with serum bilirubin (P less than 0.05). No correlations were found between cytotoxicity and circulating immune complexes, C-reactive protein or CH50. The study was controlled by serum from patients with other liver diseases. In these samples vWFAg (P less than 0.003), and bilirubin levels (P less than 0.001) were also raised relative to normal controls. vWFAg levels again correlated with levels of bilirubin (P less than 0.05). Tissue culture experiments showed that purified bilirubin was cytotoxic to human umbilical vein endothelial cells and induced the release of vWFAg. The case report of a patient with obstructive jaundice again indicated that levels of bilirubin and vWFAg were related. These results suggest that endothelial cell damage occurs in both primary biliary cirrhosis and to a lesser extent in other liver diseases, and may be mediated by cholestasis, not by humoral immunological mechanisms.


Atrial natriuretic peptide in pregnancy: response to oral sodium supplementation. 1. The control of extracellular fluid volume (ECFV) in normal pregnancy may be related to changes in atrial natriuretic peptide. Previous studies in non-pregnant subjects have suggested that plasma atrial natriuretic peptide (ANP) increases in response to dietary sodium supplementation because of an increase in plasma volume, although this has not been measured directly. 2. Nine women who were pregnant in the third trimester undertook oral sodium supplementation (136 mmol) for 5 days in addition to their usual diet. Twenty-four hour urinary sodium excretion increased by 125 +/- 54 mmol/day (mean +/- s.d.; P less than 0.01). Plasma volume was unchanged, although total ECFV tended to increase (P less than 0.09 and bodyweight increased (1.3 +/- 1.4 kg; P less than 0.01) at the end of these diets. 3. Plasma ANP increased by 30.7 [8.6, 34.5] pmol/L (median [25th, 75th percentile]; P less than 0.05), while plasma renin concentration decreased significantly from 7.3 [6.2, 11.2] to 2.6 [1.7, 3.9] pmol angiotensin I/mL (P less than 0.01), as did plasma aldosterone concentration (1435 [1162, 1722] to 753 [595, 1110] fmol/mL; P less than 0.01). Plasma vasoactive intestinal peptide was unchanged. 4. Pregnant women respond to increased dietary sodium with an increase in plasma ANP in the absence of a significant increase in plasma volume. The acute regulation of plasma ANP in response to increases in dietary sodium in pregnant women does not appear to be mediated by changes in intravascular fluid volume.


Responsiveness and sensitivity to cholinergic agonists and antagonists in bovine isolated bronchial muscle. 1. Airways derived from different levels of the lung exhibit a difference in the reactivity and sensitivity to agonists. We have evaluated the effect of acetylcholine and cholinergic selective (pirenzepine, gallamine and 4-dipherylacetoxymethyl piperidine [4-DAMP]) and non-selective (atropine) antagonists on bovine proximal and distal smooth muscle preparations. 2. The distal preparations are more sensitive to acetylcholine than proximal bronchi. The relaxant effect of three selective antagonists on the distal and proximal tissues was the same when the results for each drug were compared. 3. Atropine and 4-DAMP were more potent than pirenzepine and gallamine in relaxing both proximal and distal bovine smooth muscle preparations. 4. These data suggest that the muscarinic sites on the smooth muscle of bovine airways are of the M3 subtype.


Prejunctional actions of tacrine on autonomic neuroeffector transmission in rabbit isolated pulmonary artery and rat isolated atria. 1. This study investigated the effects of tacrine (1,2,3,4-tetrahydro-9-aminoacridine) on the resting and stimulation-induced (SI) release of radioactive substances from isolated preparations of rat atria and rabbit pulmonary artery in which the noradrenergic transmitter stores had been labelled with [3H]-noradrenaline, and from rat atrial preparations in which cholinergic transmitter stores had been labelled with [3H]-acetylcholine. In addition, the effect of tacrine on the uptake of [3H]-noradrenaline by noradrenergic nerves in rat atria was determined. 2. Tacrine produced concentration-dependent increases in the resting efflux of radioactivity from both the [3H]-noradrenaline-loaded artery and atrial preparations. Blockade of neuronal amine transport with desipramine reduced the release of radioactivity evoked by tacrine from atria but not that evoked from artery preparations. Inhibition of monoamine oxidase by pargyline pretreatment markedly reduced the tacrine-evoked release of radioactivity in both atrial and artery preparations. 3. The radioactivity released from [3H]-noradrenaline-labelled rat atrial preparations by 30 mumol/L tacrine consisted entirely of the deaminated metabolite [3H]-DOPEG. The evoked release of [3H]-DOPEG from atria was reduced by approximately 50% by desipramine (1 mumol/L). When atrial monoamine oxidase had been inhibited by pargyline treatment in vivo and in vitro, 30 mumol/L tacrine evoked the release of [3H]-noradrenaline instead of [3H]-DOPEG. However, the amounts of [3H]-noradrenaline released by tacrine when monoamine oxidase was inhibited were only about 25% of the amounts of [3H]-DOPEG released in untreated atria. 4. Tacrine, in concentrations of 1 and 10 mumol/L, enhanced the release of radioactivity evoked by field stimulation of [3H]-noradrenaline-loaded rabbit pulmonary artery preparations. This effect was unaltered by desipramine or pretreatment with pargyline. However, in artery preparations pretreated with pargyline, a high concentration of tacrine (100 mumol/L) markedly reduced SI efflux. In contrast to the findings with artery preparations, tacrine (1-30 mumol/L) did not alter SI efflux in rat atrial preparations. 5. It is concluded that tacrine displaces noradrenaline from intraneuronal transmitter stores of sympathetically-innervated tissues, and that the displaced amine is totally metabolized by monoamine oxidase before leaving the nerve terminals. When deamination of neuronal cytoplasmic noradrenaline is prevented, only a portion of the noradrenaline displaced from storage vesicles passes to the extracellular space. It is likely that the transfer of cytoplasmic noradrenaline out of the terminals is limited by the activity of the amine transport mechanism.


Intracoronary PGE2 and veratrine inhibits renin release in conscious dogs via chemosensitive ventricular afferents. 1. Prostaglandins (PG) and veratrum alkaloids stimulate ventricular sensory receptors with non-myelinated vagal afferents and mediate inhibitory circulatory responses. 2. The present study in conscious instrumented dogs was carried out to determine the effects of intracoronary artery infusions of veratrine (Ver-IC) and PGE2 (PGE2-IC) on plasma renin activity (PRA). 3. A 15-20 mmHg decrease in arterial pressure was produced during Ver-IC (0.2-0.8 micrograms/kg per min) and PGE2-IC (10-50 ng/kg per min), but there was no change in PRA or heart rate. 4. In contrast, significant increases in PRA (+3.51 +/- 0.37 ng angiotensin I/mL per h; P less than 0.01) and heart rate (+38.5 +/- 6.2 beats/min; P less than 0.001) were elicited in response to a 15-20 mmHg decrease in arterial pressure produced by intravenous infusions of nitroprusside. 5. Pharmacological blockade of afferent fibres in the pericoronary region of the left main coronary artery during Ver-IC resulted in significant hypotension-induced increases in PRA (P less than 0.001) and heart rate (P less than 0.001), thus removing the inhibitory influence of chemosensitive ventricular afferents. 6. Therefore, intracoronary veratrum alkaloids and prostaglandins inhibit hypotension-induced increases in PRA and heart rate in the conscious dog. This is mediated by chemosensitive receptors located in the left ventricular myocardium along with afferent nerves in the pericoronary region and cervical vagi.


Does the haemodynamic response to acute central hypovolaemia depend on the rate of fall of cardiac output? 1. In published studies of the effects of acute blood loss in conscious rabbits, the rates of haemorrhage have ranged for 3-9% of blood volume/min. This is potentially a confounding factor when it comes to comparing the results of different studies. We have therefore tested whether the haemodynamic response to acute central hypovolaemia depends on the rate of fall of cardiac output. 2. Cardiac output in six conscious rabbits was reduced by 4, 8 and 12% of baseline levels per min by gradual inflation of a cuff around the thoracic inferior vena cava. These rates correspond approximately to blood loss at rates of 3, 6 and 9% of blood volume/min. 3. The haemodynamic responses were biphasic. In Phase I (compensatory) there was progressive systemic vasoconstriction and tachycardia, and only a small fall in blood pressure. In Phase II (decompensatory), systemic vasoconstriction failed abruptly, arterial pressure plummeted and heart rate declined. 4. We could detect no effect of rate of fall of cardiac output on the pattern of the haemodynamic responses in either Phase I or Phase II. 5. We conclude that the rate of blood loss in different studies of haemorrhage in conscious rabbits, within the range 3 to 9 per cent of blood volume per minute, need not be regarded as a confounding factor when it comes to interpreting the results. It is likely that this conclusion can be generalized to studies of haemorrhage in other mammalian species.


Enhancement by endothelin-1 of the release of catecholamines from the canine adrenal gland in response to splanchnic nerve stimulation. 1. The effect of endothelin-1 on the release of adrenal catecholamines was examined in anaesthetized dogs. 2. Splanchnic nerve stimulation (SNS) at 1 and 3 Hz was applied before and after the intravenous injection of endothelin-1. 3. Endothelin-1 (0.1 and 0.3 micrograms/kg) significantly enhanced the release of adrenal catecholamines induced by 3 Hz SNS, but did not affect basal release and the release of adrenal catecholamines induced by 1 Hz SNS. 4. Endothelin-1 produced a slight and short-lasting fall in arterial blood pressure and decreases in adrenal and renal blood flow rates. 5. These results indicate that endothelin-1 enhances the release of adrenal catecholamines from the canine adrenal gland in response to relatively high frequency SNS.


Effect of perindopril on the development of atherosclerosis in the cholesterol-fed rabbit. 1. The aim of the study was to examine the effect of the angiotensin-converting enzyme inhibitor perindopril on the development of atheroma in the cholesterol-fed rabbit. 2. The normal human carotid artery, like most large human arteries, has a preformed diffuse intimal thickening. To model this thickening, the right carotid artery of the 12-week-old rabbit had an expanded balloon catheter passed down it to remove the endothelium and partially damage the media. 3. Fourteen weeks after this operation, a myointimal thickening similar in almost all respects to the human intimal thickening had developed. The rabbits were then divided into six groups of six rabbits fed on: (i) a 1% cholesterol diet; (ii) a 1% cholesterol diet plus a hypotensive dose of perindopril (0.3 mg/kg per day); (iii) a 1% cholesterol diet plus a non-hypotensive dose of perindopril (0.01 mg/kg per day); (iv) a normal diet; (v) a normal diet plus a hypotensive dose of perindopril (0.3 mg/kg per day); and (vi) a normal diet plus a non-hypotensive dose of perindopril (0.01 mg/kg per day). 4. After 6 weeks of treatment the animals were sacrificed. There were ameliorating effects of both hypotensive and non-hypotensive doses of perindopril on the development of plaques, as determined by the area of intima covered by Oil Red-O-staining plaque and light microscopy. 5. Cell culture studies indicated that perindopril has no effect on smooth muscle proliferation, but increases collagen and non-collagen synthesis by smooth muscle cells and decreases their binding of the atherogenic lipoprotein beta-very low density lipoprotein (beta-VLDL).(ABSTRACT TRUNCATED AT 250 WORDS)


A developmental genetic mechanism involving angiotensin in spontaneously hypertensive rats. 1. Certain genes drive the blood pressure of young spontaneously hypertensive rats (SHR) to stable hypertensive levels in adulthood. 2. Relatively brief blockade of the renin-angiotensin system in young SHR can reset the track of SHR pressure to a lower level for the life of the animal. This effect appears to be a characteristic of the SHR strain. 3. It is proposed that the expression of a particular SHR hypertensive gene depends on angiotensin and is limited to young animals. This hypothesis explains some of the phenotypic abnormalities observed in young SHR and the decremental long-term blood pressure effects following ACE inhibitor treatment. 4. The identity of the gene is unclear, but information from biochemical, physiological and pharmacological studies may direct attention to distinct candidate genes within specific chromosomal regions of interest. 5. Understanding these genetic mechanisms may have important implications for future preventive strategies.


Diabetic renal microvascular disease: the role of hypertension and ACE inhibitors. 1. It has been suggested that hypertension may be an important determinant of the rate of progression of diabetic microangiopathy. 2. Renal microvascular disease as assessed by urinary albumin excretion and glomerular ultrastructure was evaluated in a model in which streptozotocin diabetes was induced in spontaneously hypertensive rats (SHR). 3. Diabetes was associated with increases in urinary albumin excretion, and hypertension resulted in a further increase in albuminuria. 4. Various antihypertensive regimens were administered to diabetic SHR, with the angiotensin-converting enzyme inhibitor perindopril and triple therapy (hydralazine, reserpine and hydrochlorothiazide) being more effective than the calcium antagonist (lacidipine) in retarding the increase in albuminuria in diabetic SHR. 5. Antihypertensive therapy appears to ameliorate the development of diabetic renal disease.


The effect of hypertension and ACE inhibition on arterial structure and compliance. 1. Large artery dilatation may be produced by angiotensin-converting enzyme inhibition in hypertensive subjects independently of blood pressure reduction. The resulting increase in arterial compliance may be due to both blood pressure reduction and to arterial smooth muscle relaxation. 2. In healthy volunteers and in hypertensive subjects, dosages producing large artery dilatation seem to be even higher than those causing arteriole dilatation with the resulting blood pressure reduction. 3. It may be important to consider such findings for the remodelling of the cardiovascular system produced by angiotensin-converting enzyme inhibition.


Remodelling of the vascular system in response to hypertension and drug therapy. 1. Arterial remodelling is an important mechanism in the pathophysiology of hypertension and its complications, being involved in the decrease of vascular reserve, the autoregulation of cerebral blood flow and the development of atherosclerosis. There is now evidence that, in addition to several other growth factors, vasoactive peptides such as angiotensin II may act as vascular smooth muscle growth-promoting substances. Based on these data, the effects of perindopril, a potent and long-lasting angiotensin-converting enzyme (ACE) inhibitor, on structural and mechanical properties of the arterial wall have been studied in animal models of hypertension. Perindopril completely reversed the aortic medial hypertrophy and arterial stiffening observed in renovascular hypertensive rats and in spontaneously hypertensive rats. The effect of perindopril was consistent with the potent inhibition of vascular ACE, and emphasized the potential role of angiotensin II as a vascular growth modulator. Whether the time constant of remodelling is similar or not in the heart and large vessels remains an important question that requires further investigation.


Enhanced contraction to noradrenaline, serotonin and nerve stimulation but normal endothelium-derived relaxing factor response in skin small arteries in human primary hypertension. 1. We measured the reactivity of 2 mm long ring segments of human resistance arteries dissected from gluteal skin biopsies and mounted on wires in a Mulvany-Halpern myograph for recording isometric force. Arteries were taken from eight normotensive (N) volunteers (average age 46 years, blood pressure 126/82 mmHg) and eight untreated hypertensives (H; average age 48 years, blood pressure 149/101 mmHg). 2. In small diameter arteries (internal diameter less than 500 microns), the cumulative concentration-response curves to noradrenaline, serotonin and angiotensin II had a greater maximum by 72, 300 and 69%, respectively, in vessels from hypertensive patients than in those from normal volunteers. Nerve stimulation also caused a greater maximum contraction in hypertensive vessels (by 352%). 3. Arteries from H and N patients contracted submaximally by the thromboxane mimetic U46619 were similarly sensitive to the endothelium-dependent relaxing factor (EDRF) acetylcholine, indicating no difference in EDRF release or sensitivity. 4. Morphological measurements of the ratio of wall thickness to lumen radius of the wire-mounted vessels showed no significant difference between H and N vessels. 5. In larger arteries (internal diameter greater than 500 microns), no response to acetylcholine was noted in either H or N arteries. The sensitivity to serotonin and angiotensin II was similar between these arteries but the EC50 to noradrenaline was less in H than in N arteries (delta EC50 = 0.61 -log mol/L). 6. Subcutaneous resistance arteries with an internal diameter less than 500 microns from hypertensive patients show enhanced contractility to noradrenaline, serotonin and nerve stimulation despite a lack of detectable medial hypertrophy.(ABSTRACT TRUNCATED AT 250 WORDS)


The clinical pharmacology of ACE inhibitors: evidence for clinically relevant differences? 1. Potential differences among ACE inhibitors include pharmacokinetic and pharmacodynamic factors. The presence of a sulfhydryl group conferring antioxidant properties, the administration as a pro-drug to delay the onset and prolong the duration of haemodynamic effects, and the route of elimination are examples of possible differences. 2. Adverse effects of ACE inhibitors may be mediated by effects on bradykinin metabolism at tissue sites, which may be separable from haemodynamic responses mediated largely by angiotensin II withdrawal. 3. Clinically important differences between ACE inhibitors in their adverse event profile have yet to be proven. Evidence is emerging that plasma ACE inhibition and haemodynamic responses are separable, and this may indicate the potential for other organ-specific effects to differ among ACE inhibitors. 4. At present, however, the greatest distinguishing features for one compound vs another are the time to onset and the duration of action, which determine the frequency of administration.


Clinical efficacy of perindopril in hypertension. 1. Perindopril's effectiveness in mild to moderate hypertension was evaluated in three studies. 2. Perindopril was more effective than sodium restriction in reducing blood pressure, and the effects were additive. 3. Perindopril was as effective as atenolol in reducing blood pressure, and was well tolerated. 4. Perindopril lowered blood pressure to the same extent as enalapril at peak drug levels but had a greater effect at the trough level of the drugs. 5. Perindopril is an effective antihypertensive agent with an acceptable side-effect profile in people with hypertension.


Angiotensin-converting enzyme inhibition as first-line treatment for hypertension. 1. Perindopril (4 mg) was compared with atenolol (50 mg), captopril (25 mg b.d.) or a diuretic (hydrochlorothiazide 50 mg and amiloride 5 mg) in three studies involving a total of 503 hypertensive patients with a diastolic blood pressure (DBP) of 95-125 mmHg. 2. A 4 week single-blind placebo period preceded 12 weeks of active treatment. Dose titration was at weeks 4 and 8 if supine DBP greater than 90 mmHg. The dose was doubled and if necessary a diuretic was added in the atenolol or captopril comparisons, and atenolol was added in the diuretic study. 3. The fall in supine blood pressure (BP) was 27/17 mmHg with perindopril and 21/16 mmHg for atenolol. Monotherapy controlled 55% of patients on perindopril and 48% on atenolol, increasing to 78% and 58% with the addition of hydrochlorothiazide, respectively. Captopril caused a BP fall of 19/12 mmHg compared with 27/18 mmHg for perindopril, with 49% of both groups being controlled on monotherapy. 4. Diuretic addition produced a greater antihypertensive effect with perindopril (75%) compared with 57% for captopril in achieving control. Perindopril caused a comparable fall in supine BP to the diuretic combination 27/19 mmHg and 31/18 mmHg, but the fall in erect systolic BP was significantly greater for the diuretic. At 3 months, 85% of the diuretic group and 78% of the perindopril group achieved the target BP. 5. A multicentre trial of 856 patients treated with perindopril (690 patients treated for 1 year or more) has shown that BP control is maintained in the long term with a low incidence of side-effects (7.9%) causing withdrawal from treatment.(ABSTRACT TRUNCATED AT 250 WORDS)


Expression of interleukin-1 and interleukin-1 receptor antagonist by human rheumatoid synovial tissue macrophages. Interleukin-1 (IL-1) has protean effects in the pathogenesis of rheumatoid arthritis (RA). These effects include production of prostaglandins and collagenase from rheumatoid fibroblasts as well as upregulation of adhesion molecule expression on these cells. IL-1 can activate monocytes and neutrophils, as well as promote the growth of fibroblasts and endothelial cells. Recently, a novel interleukin-1 receptor antagonist protein (IRAP) has been isolated, purified, cloned, and expressed, which may modulate the effects of IL-1. In this study, we present data demonstrating that macrophages isolated from human RA synovial tissues express both IL-1 and IRAP genes. In addition, RA synovial tissue macrophages and lining cells display IL-1 and IRAP antigenic expression by immunohistochemistry. In contrast, osteoarthritis synovial tissues, as compared to RA, have fewer IL-1 and IRAP-positive macrophages. Thus, the production of IL-1 balanced by IRAP may affect the joint destruction found in these diseases.


Stimulation of human peripheral blood mononuclear cells with anti-CD3 monoclonal antibody vs IL2: disparate effects on T cell-dependent B cell differentiation despite similar effects on generation of unrestricted cytolytic activity. Despite their each inducing MHC-unrestricted cytolytic activity in overnight PBMC cultures mediated predominantly by CD56+ non-T cells, anti-CD3 mAb and rIL2 induce diametrically opposite effects on subsequent polyclonal T cell-dependent B cell differentiation. When added to fresh autologous PBMC, irradiated anti-CD3-stimulated PBMC inhibit generation of Ig-secreting cells (IgSC) in the secondary cultures, whereas irradiated rIL2-stimulated PBMC enhance IgSC generation. Neither carryover of the respective stimuli nor quantitative differences in levels of cytolytic activity against Daudi cells, autologous PBMC, or autologous activated B cells can explain the dichotomous anti-CD3- vs rIL2-induced effects on B cell differentiation. For both anti-CD3- and rIL2-induced effects on B cell differentiation, CD56- cells, including CD4+ and CD8+ cells, play a more dominant role than they do in generation of MHC-unrestricted cytolytic activity. In addition, although rIL2-induced enhancement of IgSC generation is insensitive to monocyte depletion by plastic adherence or by treatment with leucine methyl ester, anti-CD3-induced inhibition of IgSC generation is highly sensitive to monocyte depletion, indicating that, at least for anti-CD3-induced inhibition, multiple cell populations are required to generate the functional effect. Taken together, these results indicate that differences in the means of generating in vitro tumoricidal activity may have profound ramifications for non-cytotoxic immune parameters, such as B cell differentiation. Not only might this be an important issue to address in adoptive immunotherapy protocols for cancer patients but also adoptive immunotherapy might be applicable to certain autoimmune disorders if the ability to inhibit B cell differentiation could be channeled against the pathogenic antibody-producing B cells.


Modification of thymic cell subsets induced by long-term cocaine administration during a murine retroviral infection producing AIDS. LP-BM5 murine leukemia virus (MuLV) infection and cocaine administration are known to impair the murine immune system. We have developed a murine model to study the effect of daily cocaine administration and retrovirus infection on the lymphoid cell populations of the thymus. C57BL/6 female mice were studied following chronic cocaine administration for 11 weeks with simultaneous LP-BM5 MuLV infection. Cocaine administration reduced body and thymus weight, significantly reduced the number of CD8+ cells in the thymus, and partially prevented thymus enlargement due to lymphoid cell proliferation induced by LP-BM5 MuLV infection. Retrovirus infection was associated with a decrease in the percentage and absolute number of Thy 1.2+, CD4+, and CD8+ cells in the thymus, an effect potentiated by cocaine administration. Therefore cocaine impairs thymic function by altering the number of cells expressing T cell differentiation markers in MAIDS.


Effects of rapamycin on human HLA-unrestricted cell killing. Rapamycin (RAPA) is a potent immunosuppressant and can effectively prevent allograft rejection at a dosage 10- to 100-fold lower than that of cyclosporin A. RAPA strongly inhibits proliferation and function of T and B cells. In this study, we investigated the effect of RAPA on human HLA-unrestricted cell killing. It was shown that in vitro RAPA inhibited the cytolytic effect of natural killer cells and lymphokine-activated killer cells (LAK) and inhibited antibody-dependent cell-mediated cytotoxicity. The effective concentration of RAPA was 10- to 100-fold higher than that required for inhibiting T cell proliferation. These results suggest that there could be a therapeutic dose window at which RAPA inhibits T cell activity while it leaves HLA-unrestricted cell killing unaffected. We also demonstrated that while IL4 inhibited LAK activity, and RAPA inhibited IL4-promoted T cell proliferation, RAPA was not able to antagonize IL4's inhibitory effect on LAK. This indicates that the mechanism of interaction between RAPA and IL4 on LAK is different from that on T cells.


Treatment of coxsackievirus B3 myocarditis by immunoactive peptide in an animal model. The effect of immunostimulant therapy on acute viral myocarditis, induced with coxsackievirus B3 (CB3), was investigated in C3H/He mice. Peritoneal exudate cells (PEC) or spleen cells (SC) from mice pretreated with a synthetic immunoactivating peptide FK565 significantly inhibited the multiplication of CB3 in C3H/He mouse embryo fibroblast cells compared with PEC or SC from nontreated mice in vitro (6.45 +/- 0.20 log10 PFU/ml; control: 6.85 +/- 0.05, P < 0.05; 6.40 +/- 0.07, control: 6.78 +/- 0.07, P < 0.05, respectively), although FK565 did not inhibit viral replication directly. Mice were inoculated intraperitoneally with 3 x 10(5) plaque-forming units of CB3. FK565, 1 or 10 micrograms/kg, given intraperitoneally daily started on the same day of viral inoculation. To determine CB3 virus titer, mice were killed on Day 3. To study survival and myocardial histopathology, mice were killed on Day 20. Histopathological findings were scored on a scale of 0 to 4. FK565, 10 micrograms/kg/day, effectively inhibited myocardial viral replication (3.23 +/- 0.42 log10 PFU/mg, control: 3.71 +/- 0.40, P < 0.05), reduced the cellular infiltration (1.3 +/- 0.7, control: 2.5 +/- 0.5, P < 0.05), myocardial necrosis (1.4 +/- 0.9, control: 3.0 +/- 0.6, P < 0.01), and calcification of the heart (1.0 +/- 0.6, control: 2.5 +/- 0.5, P < 0.01) and increased survival (60%, control: 30%, P < 0.05). The present study suggests that immunostimulant therapy improves the course of viral myocarditis during the viral-mediated phase. The inhibitory activity of FK565 seems to be due to the activation of host defense mechanisms.


Indications for the presence of antibodies cross-reactive with HTLV-I/II, but not HIV, in patients with myelodysplastic syndrome. Serological evidence is presented for the fact that patients with the myelodysplastic syndrome exhibit a statistically significant reactivity in confirmatory assays for antibodies to human T-lymphotropic viruses types I and II (HTLV-I/II). This antibody reactivity, evident by indirect immunofluorescence and Western blot, was not confined to HTLV core antigens but extended to native and recombinant envelope glycoproteins. The effect was also observed in cases of acute myeloic leukemia, albeit to a lesser degree. It was essentially absent from patients with chronic myeloic leukemia or lymphocytic leukemias and healthy or multitransfused controls. No antibodies to human immunodeficiency viruses types 1 or 2 were detected in any of the specimens. The investigated clinical population had no known risk factor for retroviral infection other than a history of multiple platelet transfusions, and none of the specimens was seropositive for HTLV-I or HTLV-II according to recommended criteria. The cause of this cross-reactivity remains to be determined.


Immunologic abnormalities in canine juvenile polyarteritis syndrome: a naturally occurring animal model of Kawasaki disease. This study describes the immunologic abnormalities during the acute phase of juvenile polyarteritis syndrome (JPS), a multisystem necrotizing vasculitis of young dogs with a predilection for the coronary arteries. JPS has striking clinical, laboratory, and pathologic similarities to Kawasaki disease (KD), the most common cause of acquired heart disease in children in the United States. The immunologic abnormalities include an increase in serum IgA, an increase in the percentage of peripheral B cells and a decrease in the percentage of total peripheral T cells, a marked suppression of the blastogenic response to mitogenic stimulation, an inability to generate immunoglobulin-secreting plasma cells following polyclonal activation, the presence of antineutrophil cytoplasmic antibodies, and evidence of monocyte/macrophage activation. These immunoregulatory abnormalities are similar to those observed in children during the acute phase of KD. This unique, naturally occurring animal model of necrotizing vasculitis may prove useful for investigating novel therapeutic interventions in the treatment of necrotizing vasculitis and may yield insight into the immunopathology and etiology of KD.


Idiotypic heterogeneity of VKIII autoantibodies to red blood cell antigens. VKIII light (L) chains are commonly expressed by human autoantibodies with diverse binding specificities, including red blood cell antigens. To better understand the physiologic and pathologic expression of these L chain variable region genes, we have created a panel of murine monoclonal anti-idiotypic antibodies by immunization with a human lymphoblastoid B cell line that secretes an IgM VKIII autoantibody specific for the I red blood cell carbohydrate determinant. The binding specificities of these nine murine monoclonal antibodies, termed IV.1-IV.9, were evaluated against a large panel of monoclonal Ig proteins and compared to two previously well-characterized monoclonal anti-idiotypes, 6B6.6 and 17.109; these two anti-idiotypes have been shown to primarily identify VKIII rheumatoid factors derived from the kv328 (VKIIIa) and kv325 (VKIIIb) genes, respectively. In contrast, our anti-idiotypic antibodies identified (public) cross-reactive idiotypes present on many VKIII proteins that included both anti-erythrocyte and rheumatoid factor autoantibodies. Certain anti-idiotypic antibodies (IV.2 and IV.6) were restricted to VKIIIa L chains but differed from the 6B6.6 anti-idiotype by binding to a larger subset of VKIIIa proteins representing the products of at least two VKIIIa genes. One antibody of our panel (IV.5) recognized a private idiotope expressed only by the immunizing antibody. Using the panel of anti-idiotypic antibodies to evaluate erythrocyte autoantibodies with different serologic specificities, we found striking heterogeneity of L chain idiotype expression, even among known VKIII anti-i/I autoantibodies. These findings differ from the recently described structural and idiotypic conservation associated with the H chain of anti-i/I autoantibodies. From correlations of idiotypic reactivity with L chains of known sequence, it is postulated that the observed heterogeneity of L chain idiotype expression is due to differences in the genetic origin and/or somatic diversification of L chain variable region genes. Furthermore, subtle variability of L chain structure may contribute in part to the differences in fine binding specificity among anti-I and anti-i autoantibodies.


Tumor necrosis factor production is deficient in diabetes-prone BB rats and can be corrected by complete Freund's adjuvant: a possible immunoregulatory role of tumor necrosis factor in the prevention of diabetes. The Bio-Breeding (BB) rat develops spontaneous insulin-dependent diabetes mellitus (IDDM) and provides a useful animal model to study this human autoimmune disease. Treatment of BB rats with tumor necrosis factor (TNF) has been reported to prevent the development of IDDM. This suggests that deficient TNF production may be involved in the immunopathogenesis of autoimmune diabetes. In this study, we evaluated TNF production in diabetes-resistant (DR) BB rats, diabetes-prone (DP) BB rats, and DP BB rats protected from diabetes by the immunoadjuvant, complete Freund's adjuvant (CFA). TNF production in short-term cultures of peritoneal macrophages from DP rats was significantly less than that from control DR rats, both in the basal state and after stimulation with either interferon-gamma (IFN-gamma) or lipopolysaccharide (LPS) in vivo and in vitro. In contrast, TNF production by macrophages from CFA-injected DP rats (basal and IFN-gamma or LPS-stimulated) was equal to or greater than that by macrophages from DP rats and similar to TNF production by macrophages from CFA-injected DR rats. These results suggest that development of autoimmune diabetes in BB rats may be causally related to deficient macrophage production of TNF, and that upregulation of TNF production may protect against diabetes development.


Markers of inflammatory activation: upregulation of complement receptors CR1 and CR3 on synovial fluid neutrophils from patients with inflammatory joint disease. Expression of the C3 receptors CR1 and CR3 was investigated on neutrophils from paired peripheral blood and synovial fluid samples from 34 patients with inflammatory joint disease (21 patients with rheumatoid arthritis (RA) and 13 patients with other articular diseases (OAD)). Using monoclonal antibodies (anti-CD35, anti-CD11b) and immunofluorescence flow cytometric analyses the percentages of positively labeled cells and the relative fluorescence intensities (as a measure of receptor number) were determined. CR1 and CR3 were found to be present on the majority (> 85%) of circulating neutrophils from normal subjects, RA and OAD patients, and on synovial fluid neutrophils from both patient groups. A strong correlation between neutrophil CR1 and CR3 expression was observed in peripheral blood samples from normal subjects (r = 0.81; P = 0.001), RA (r = 0.79; P = 0.001), and OAD patients (r = 0.83; P = 0.001); in each case the levels of CR3 expression were approximately twice those recorded for CR1. Both CR1 and CR3 expression was upregulated on synovial fluid neutrophils compared with that observed on the corresponding peripheral blood cells. Mean percentage increases observed were: RA patients: CR1, 16.5% (P < 0.001) and CR3, 28.7% (P < 0.001); and OAD patients: CR1, 4.1% and CR3, 26.9% (P = 0.001). Correlation of serum and synovial fluid IL-6, IL-8, and immune complex levels with neutrophil CR1 and CR3 expression failed to demonstrate any significant relationship between the concentrations of these soluble factors and receptor expression. Upregulation of CR1 and CR3 receptors, reflecting neutrophil activation within the inflamed joint, is a consistent finding in patients with inflammatory arthropathies.


Identification of autoantigen recognized by autoimmune ophthalmopathy sera with immunoblotting correlated with orbital computed tomography. We have demonstrated that there is an antibody related to extraocular muscle enlargement in autoimmune ophthalmopathy (Graves' ophthalmopathy, thyroid-associated correlated with orbital computed tomography (CT). This study was designed to identify the autoantigen and to determine whether there are common antigens among the extraocular muscle, the lacrimal gland, and the thyroid. We prepared a 100,000g sediment fraction of porcine extraocular muscle, lacrimal gland, thyroid, and human thyroid, followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting with sera from patients with Graves' disease, with or without ophthalmopathy, classified by symptoms and signs combined with orbital CT and normal controls. The results showed there was an approximately 55-kDa protein band which was recognized by the sera in 32.1% (9/28) of patients with autoimmune ophthalmopathy and in 47.3% (9/19) of patients with extraocular muscle enlargement demonstrated by orbital CT. It was significantly higher than the positive rates in patients without autoimmune ophthalmopathy and normal controls (15.8 and 11.1%, respectively, P < 0.025). However, there was no common antigen among the extraocular muscles, the lacrimal gland, and the thyroid. To further confirm this eye muscle-specific antigen, the approximately 55-kDa protein band was cut and solubilized from the nitrocellulose paper after SDS-PAGE, and electrophoretically transferred and used as an antigen in enzyme-linked immunosorbent assay. The absorbance was significantly higher in patients with autoimmune ophthalmopathy than patients without ophthalmopathy (P < 0.005), and normal controls (P < 0.01). Our findings suggest that an approximately 55-kDa protein may be a possible antigen in the eye muscle related to autoimmune ophthalmopathy.


Human anti-F(ab')2 antibodies show preferential reactivity for F(ab')2 molecules bearing lambda light chains. In order to evaluate binding specificities of anti-F(ab')2 antibodies from patients with systemic lupus erythematosus (SLE) and from normal healthy controls, F(ab')2 fragments were prepared from 24 IgG myelomas with defined isoelectric points, DNA-associated idiotypes, and kappa/lambda light chain types. Using ELISA and hemagglutination assays, anti-F(ab')2 antibodies from 12 healthy controls and 29 SLE patients were observed to exhibit preferential binding (lambda > kappa) to myeloma F(ab')2 fragments composed of lambda light chains (P < 0.0001). No correlation of anti-F(ab')2 binding and presence of cationic, neutral, or anionic isoelectric points or for DNA-associated idiotypes on monoclonal F(ab')2 was detected. Anti-F(ab')2 antibodies, often elevated in SLE during remission, show preferential specificity for F(ab')2 fragments bearing lambda light chains.


Possible supplemental mechanisms in the pathogenesis of AIDS. Multiple and diverse mechanisms have been proposed as supplements to the HIV-1 virus in the destruction of CD4+ cells and the pathogenesis of AIDS. But it is now realized that 100 times more CD4+ cells are infected with HIV-1 than was originally thought to be the case, and many antigen-presenting cells are infected as well. In addition to the direct cytopathic effect of the virus, one or a few supplemental mechanisms may well suffice to explain the progressive loss of CD4+ cells, e.g., the considerable variation in the virus and/or the destruction of uninfected CD4+ cells by one immunological mechanism or another. However, it is not yet possible to state confidently which additional mechanism(s) is important. Identification of the nature of this supplemental process has become essential for successful, nonharmful intervention.


Murine susceptibility to mercury. I. Autoantibody profiles and systemic immune deposits in inbred, congenic, and intra-H-2 recombinant strains. Inbred, congenic, and intra-H-2-recombinant mouse strains were given subcutaneous injections of either 1.6 mg HgCl2/kg body wt or 0.1 ml NaCl thrice weekly for 5-6 weeks. Mercury-treated mice from strains carrying the H-2s haplotype developed antinucleolar antibodies (ANoA), which targeted the 34-kDa nucleolar protein fibrillarin, and in some instances also nucleolar proteins of 60-70 and 10-15 kDa, the latter corresponding to histones. Strains with H-2b and H-2d haplotypes were resistant to induction of ANoA. The susceptibility to development of AnoA/antifibrillarin antibodies (AFA) was mapped to the H-2A-region using intra-H-2-recombinant strains. We were not able to confirm earlier reports that expression of H-2E genes dampens the development of ANoA. Mercury treatment caused a substantial increase in the titer of antichromatin (ACA) and/or antihistone (AHA) antibodies in a fraction of SJL/J, A.SW, A.TH, B10.S, and B10.HTT mice (H-2s), and in A/J (H-2k) mice, whereas mice from the C57BL/6J and C57BL/10J (H-2b), and the DBA and BALB/c (H-2d) strains were low or nonresponders. The development of AHA and ACA could not be linked to the H-2 complex. A significant, substantial increase of granular mesangial and systemic vessel wall IgG deposits occurred in mice with serum ANoA/AFA. However, the B10.S(9R) and B10.HTT strains, which express the H-2E genes, developed only an intermediately increased titer of mesangial IgG deposits. Systemic vessel wall IgG deposits occurred in only 60-80% of the B10.S(9R) mice and in none of the B10.HTT mice. This contrasted with the high titer of mesangial IgG deposits and uniform development of systemic vessel wall IgG deposits observed in B10.S mice not expressing H-2E. Mice with mesangial IgG deposits showed a mild glomerulonephritis. There was no systemic vasculitis. The susceptibility to development of ANoA, AHA, ACA, and systemic, granular IgG deposits in the B10.S strain was influenced by the sex, since males showed less uniform development of these immunopathologic features than females.


Pheromone 4 gene of Euplotes octocarinatus. We have cloned and sequenced a 1.7 kb macronuclear chromosome encoding the pheromone 4 gene of Euplotes octocarinatus. The sequence of the secreted pheromone is preceded by a 42 amino acid leader peptide, which ends with a lysine residue. The sequence coding for the leader peptide contains information for a putative signal peptide and is interrupted by a 772 bp intron as shown by comparison with a cDNA clone. A 64 bp intron and a 145 bp intron interrupt the sequence coding for the secreted pheromone. The three introns contain typical 5' and 3' splice junctions and a putative branch point site. The small introns have a low GC content. The large intron has a GC content similar to that of the pheromone 4 gene exons. The amino acid sequence of pheromone 4, deduced from both the genomic DNA and the cDNA of pheromone 4, shows that the secreted pheromone consists of 85 amino acids. One of its amino acids is encoded by a UGA codon. Since it has been shown for pheromone 3 of E. octocarinatus that UGA is translated as cysteine, it is assumed that the UGA codon encodes cysteine in pheromone 4 as well. The 164 bp noncoding region upstream of the leader peptide is AT-rich and contains an inverted repeat capable of forming a stem-loop structure with a stem of 11 bp. The 151 bp noncoding region at the 3' end of the chromosome contains a putative polyadenylation sequence and an inverted repeat. The macronuclear molecule is flanked by telomeres and carries the pentanucleotide motif TTGAA, located at a distance of 17 nucleotides from the telomeres. This motif has been suggested to be involved in the formation of macronuclear chromosomes.


Ciliary polypeptides and glycoconjugates of wild-type and mutant Tetrahymena thermophila: starved versus nonstarved. To investigate the role of cilia in mating interactions of Tetrahymena thermophila, ciliary membrane-rich fractions were isolated from two wild-type strains, a non-discharge mucocyst mutant which possesses mating behavior similar to wild-type, and a mating mutant which is able to costimulate cells of complementary mating type but cannot enter into pair formation. In each case, proteins from the ciliary membrane-rich fractions of starved, mating-competent ("initiated") cells were compared with those from non-starved, mating-incompetent ("non-initiated") cells, by gel electrophoresis and lectin blotting. In stained gels, a 43 kDa polypeptide was reduced or absent in initiated cells but present in non-initiated cells, in all strains. In silver-stained gels, a 25 kDa polypeptide was present in all strains, both initiated and non-initiated. In blots probed with Con A-peroxidase, a 25 kDa glycoprotein was present in ciliary membrane fractions from non-initiated cells and absent in membranes of initiated cells of the two wild-type strains and the mucocyst mutant, but is present in initiated and non-initiated cells of the mating mutant (several hypotheses are presented to explain these findings). In addition, ciliary proteins of the mating mutant included at least two unique Con A-binding polypeptides. Our results support the idea that development of mating competence during starvation involves an extensive remodeling of ciliary membranes, and identify a 25 kDa glycoconjugate as having a potential role in control of pair formation during mating.


Mapping the mating type locus of Tetrahymena thermophila: meiotic linkage of mat to the ribosomal RNA gene. Tetrahymena thermophila has a multiple mating type system. While a sexually mature cell usually expresses only one mating type, its germline (micronucleus) carries the genetic potential for 5 to 7 mating types. The set of allowed mating types is specified by the mat locus. The choice of which particular mating type is expressed by a cell reflects a somatically inherited, developmentally programmed differentiation of the somatic nucleus (macronucleus). In this work we report that the mat locus maps to the left arm of chromosome 2, as determined by nullisomic deletion mapping. We also report a distance of 29 cM between the mat locus and the ribosomal RNA gene, previously mapped to chromosome 2L. This represents another (rare) case of meiotic linkage in Tetrahymena.


Development of sexual maturity in the ciliate Euplotes crassus: sources of variation in the timing of maturity. The life styles of ciliated protists are particularly suitable for experimental analyses of certain aspects of developmental and genetic biology. The progression from sexual immaturity to maturity to senescence represents one of the most intriguing aspects of developmental programs. The extent to which progeny clones, their subclones, and testers used in the assay result in different lengths of immaturity has been investigated in Euplotes crassus. Six subclones from each of 12 progeny clones from a cross between stocks EC1 and EC2 were tested for maturity with stocks EC3, EC4, and EC5 on every transfer. Analysis of variance was used to partition the total variation in fissions to maturity into parts due to clones, subclones, and testers and the interactions between these levels. The error, interaction of subclones and testers, corresponds to a standard deviation of only 4.1 fissions, while the within clone within tester means range from 15.2 to 46.7 fissions; all levels except testers contribute significantly to the total variation. Most of the variability is attributable to clones (66%), the next most to error (16%), the next most to interaction of clones by testers (13%), and the least to subclones (5%). An a posteriori analysis examined whether the differences among clones were due to the cytoplasm of the clone ancestor (exconjugant), its mat (mating-type) locus genotype, or the mated pair it came from. None of these characteristics was able to interpret simply the large variability among clones. These results provide evidence that the transition from immaturity to maturity is quantitative and complex rather than a jump from one well-defined state to another.


Suicide is not the inevitable outcome of "perpetual" selfing in tetrahymenines collected from natural habitats. A significant fraction of the Tetrahymena clones isolated from natural habitats self (mating occurs within a clone). Early attempts to study such clones failed because stable subclones were rarely, if ever, observed, and isolated pairs all died. Isozyme analysis revealed that these wild selfers were a diverse group; some were very similar to T. australis, a species with synclonal mating type determination and to T. elliotti, shown recently to have a karyonidal mating type system. One originally stable clone of T. australis included some selfing clones after a few years in our laboratory. Other clones manifested unique zymograms. Subclones isolated from 18 selfer strains were heterogeneous. All subclones of several selfers mated massively at each transfer through 100 fissions. Selfing among subclones of other selfers was highly variable or not observed. Although 77% of the pairs isolated died, and 9% of the pair cultures selfed, 15 selfers yielded some viable nonselfing "immature" progeny. Additional immature progeny were obtained by isolating pairs from macronuclear retention synclones. Although some "immature" progeny eventually selfed, most remained stable. Giemsa staining revealed macronuclear anlagen in nearly all mating pairs and some anomalies. Crosses among the F1 progeny clones of the T. elliotti selfers yield viability data comparable to those from crosses among normal strains. Perhaps perpetual selfing is a mechanism of getting rid of deleterious combinations of genes and uncovering better combinations in homozygous state by playing genetic roulette.


Developmental expression of macronuclear specific antigen in Paramecium caudatum. We obtained a monoclonal antibody (MA-1) specific for macronuclei of the ciliate Paramecium caudatum and P. dubosqui. Immunoblotting showed that the antigen was a polypeptide of 50 kilodalton (kDa). During the process of nuclear differentiation in P. caudatum, the MA-1 antigens appeared in the macronuclear anlagen immediately after four out of eight post zygotic nuclei differentiated morphologically into the macronuclear anlagen. Afterwards, the antigens could be detected in the macronucleus through the cell cycle, and disappeared when the macronucleus began to degenerate in exconjugant cells. These results suggest that the antigens may play a role in the differentiation and function of the macronucleus.


Mutation affecting cell separation and macronuclear resorption during conjugation in Tetrahymena thermophila: early expression of the zygotic genotype. A new recessive conjugation lethal mutation was found in Tetrahymena thermophila which was named mra for macronuclear resorption arrest. Other events affected by the mra mutations are separation of pairs, DNA replication in the macronuclear anlagen, and resorption of one of the two micronuclei. In wild-type crosses 50% of the pairs had separated by 12 hr after mixing two mating types and had completed resorption of the old macronucleus 1-2 hr later. In contrast most mra conjugants did not separate even by 24 hr after mixing and the old relic (condensed) macronucleus was seen in over 90% of them. After addition of 10 mM calcium to the conjugation medium, the mra conjugants did separate but they still failed to complete resorption of the old macronucleus and to replicate macronuclear anlagen DNA in the exconjugants. The calcium induced separation of the mra conjugants occurred later than the separation of control pairs. During normal conjugation cell separation occurs before the first expression of known macronuclear genes and prior to processing of the macronuclear DNA. Therefore, the mra phenotype infers that separation of conjugants requires a signal which is produced by the macronuclear anlagen at an unusually early time.


Scrambled actin I gene in the micronucleus of Oxytricha nova. In the hypotrichous ciliate Oxytricha nova the cloned precursor gene from the micronuclear genome that encodes actin I is composed of highly disordered blocks of deoxynucleotide sequences. We present and illustrate in detail a recombination model that explains how the actin I gene may be unscrambled during macronuclear development after cell mating. The model was described in a previous publication (Greslin et al.: Proc Natl Acad Sci USA 86:6264-6268, 1989). Here we show the data, described in the earlier publication, that support the model. The data show that scrambling is not an artifact of cloning. They rule against the presence of an unscrambled copy of the actin I gene in the micronucleus, which means that unscrambling must be a part of macronuclear development. Finally, the data prove that the actin I gene in O. trifallax is scrambled in a pattern that resembles the pattern in O. nova.


Tetrahymena telomerase RNA levels increase during macronuclear development. Telomeres, the G-rich sequences found at the ends of eukaryotic chromosomes, ensure chromosome stability and prevent sequence loss from chromosome ends during DNA replication. During macronuclear development in Tetrahymena, the chromosomes fragment into pieces ranging from 20 kb to 1,500 kb. Tetrahymena telomerase, a ribonucleoprotein, adds telomeric (TTGGGG)n repeats onto telomeres and onto the newly generated macronuclear DNA ends. We have investigated whether telomerase RNA levels increase during macronuclear development, since such an increase might be expected during chromosomal fragmentation. The steady-state level of the telomerase RNA component was used to estimate the abundance of telomerase present in mating and nonmating Tetrahymena. Northern blot analysis revealed that in vegetatively growing Tetrahymena, there were 18,000-40,000 copies of telomerase RNA per cell. In mating cultures, the levels of RNA increased 2- to 5-fold at 9-15 h, and 1.5- to 3.5-fold in starved nonmating cultures. This increase in telomerase RNA paralleled telomerase activity, which also increased slightly in mating and starved nonmating cells.


Stochastic developmental variation in the ratio of allelic rDNAs among newly differentiated, heterozygous macronuclei of Tetrahymena thermophila. Ciliates possess nuclear dimorphism, i.e., they carry two structurally and functionally differentiated types of nuclei. The micronucleus and macronucleus serve as the germline and somatic nuclei, respectively, of the cell. The macronucleus differentiates from a mitotic sister of the micronucleus once per life cycle. Macronuclear differentiation is accompanied by a developmentally programmed set of DNA rearrangements, including chromosome fragmentation, telomere addition, and amplification. Given the diploidy of the MAC anlage, are both homologous copies of a chromosome processed and amplified equally and simultaneously in an individual differentiating MAC? We have approached this question for the case of the rDNA, exploiting previously identified DNA polymorphisms and the sensitivity of PCR. We determined allelic ratios in individual caryonide cells, i.e., the cells carrying the primary products of MAC differentiation, prior to the first division of the newly differentiated MAC. We observed stochastic variability in allelic ratios among caryonides that start with genetically identical heterozygous MACs. Either rDNA type can be in the majority. Appropriate controls make it unlikely that the ratios observed were significantly affected by variation in the assay itself. The variability may well result from the statistical variation associated with the relative timing of individual biochemical events initiating the processing and/or amplification of a few rDNA precursor molecules, presumably 4-8 at the most, in a MAC anlage. In addition to this stochastic variability, we observed a small but distinct bias in favor of the C3 rDNA. Thus the replication advantage of C3 relative to B rDNA in heterozygous MACs, previously detected during vegetative multiplication, may begin to be expressed during developmental amplification.(ABSTRACT TRUNCATED AT 250 WORDS)


Developmental analysis of the cell recognition mechanism in the ciliate Euplotes raikovi. Euplotes raikovi, like other ciliates, passes through a postconjugal immaturity, operatively identified by an apparent cell inability to form mating pairs under experimental conditions that are the same as those used for inducing mating at maturity. In cells homozygous for the gene mat-2, which controls the pheromone Er-2, Er-2 mRNA synthesis and mature Er-2 secretion were shown to start from the very beginning of the life cycle and continue throughout immaturity, although to extents estimated to be 5- to 10-fold lower than at maturity. In addition, experiments of 125I-Er-2 binding and crosslinking provided evidence that autocrine pheromone-binding sites, showing values of the dissociation constant of the order of 10(-9) M, are on the surface of immature cells. The number of these sites per cell was estimated to increase from less than 10(6) per cell of 5-7 fissions of age, to about 16 x 10(6) at maturity. These results were taken to suggest that a pheromone-receptor production is stimulated during immaturity by autocrine pheromone binding to cells and that this production might be essential for the development of a pheromone-receptor density high enough to transform the cell from "immature" to "adult," that is competent to respond as well to pheromones of conspecific, genetically different cells.


Periorbital hemangiomas.

Periorbital hemangiomas. 1. Any hemangioma that involves the upper or lower lid and leads to partial closure in infancy may interfere with or prevent development of normal binocular vision in a matter of days to weeks. 2. Hemangiomas least likely to interfere with vision are lower lid lesions occupying one third of the lid margin or less, not extending beyond the eyelid region, and resolving early. 3. Hemangiomas associated with deprivation amblyopia (with or without anisometropia) are lesions occupying more than one half of the lid margin, extending beyond the eyelid region, resolving late, and obstructing the visual axis. 4. Hemangiomas associated with isolated anisometropic amblyopia are local but bulky lesions that are usually but not always restricted to the upper lid, closing the eye partly and resolving late. 5. The treatment of choice for periorbital hemangiomas is corticosteroids, either systemic or intralesional.


Ocular melanoma.

Ocular melanoma. Ocular melanomas are the most common intraocular malignancy in adults. The majority of ocular melanomas are choroidal melanomas. These tumors can be difficult to diagnose, especially when they are small. Documented growth of a lesion on serial examinations is the most important clinical feature favoring the diagnosis of a choroidal melanoma. Diagnostic studies including ultrasonography and angiography may be helpful in the diagnosis of these tumors. A number of treatment options are available for choroidal melanomas. These include photocoagulation, radiation therapy, local tumor resection, and enucleation.


Periocular tumors.

Periocular tumors. Next to the fear of death from cancer, patients fear loss of sight more than anything else. They are especially fearful of the potential for visual impairment when confronted with the need to treat an eyelid neoplasm. Patients need reassurance that the treatment will not compromise vision and that their visual needs will be attended to. Optimally, the responsibilities for patient management are coordinated and shared in a team approach. Although many tumors around the eye are easily managed, a large proportion of them are significant by virtue of their size and location. These are best treated by a team that is prepared to provide optimal assessment, can deal with any size lesion and its repair, and is familiar with the spectrum of complications and their management.


Lasers in dermatology and ophthalmology. Dermatology and ophthalmology are two specialties that have made exceptional use of laser technology. In dermatology, port wine stains and hemangiomas, neoplastic lesions, and adnexal tumors are amenable to laser treatment. In ophthalmology, the use of lasers to effect photocoagulation, photoradiation, photovaporization, photodisruption, and photodecomposition has permitted the treatment of vascular retinal disease, macular edema, intraocular tumors, open angle glaucoma, and angle closure glaucoma. Although great strides in laser technology have been made, the future is even more promising as laser devices are further modified to treat specific disease processes.


Regional anesthesia of the eye and orbit. The principles and techniques of providing topical and regional anesthesia to the eye are presented in this article. Potential complications and their treatments are outlined, with special emphasis placed on the characteristics of the oculocardiac reflex.


Oculocutaneous manifestations observed in multisystem disorders. Patients with multisystem disorders frequently present with or eventually manifest cutaneous disease. Many of these patients will also manifest ocular changes. In these disorders, the dermatologist or ophthalmologist may act as primary provider or consultant. Thus, familiarity with these conditions will enable the specialist to provide better care for these patients. This article reviews the oculocutaneous manifestations of sarcoidosis, Behçet's disease, Reiter's syndrome, and Sjögren's syndrome.


Ocular and periocular infections.

Ocular and periocular infections. The eye is an important site for infectious disease because an incorrect diagnosis can cause loss of vision or loss of life. An approach to accurate diagnosis, intervention, and therapy is outlined.


Lyme disease.

Lyme disease. Lyme disease is a multisystem disorder caused by the spirochete Borrelia burgdorferi. It is transmitted to human and animal hosts primarily by ticks of the Ixodes ricinis complex. Recognition of its characteristic skin and eye manifestations facilitates diagnosis and treatment.


Acquired immunodeficiency syndrome and the eye. Patients with AIDS or ARC may develop ocular manifestations falling in four broad categories: (1) conjunctival and periorbital disease, (2) neuro-ophthalmologic abnormalities, (3) retinal microangiopathy, and (4) opportunistic retinal and choroidal infections. Careful ophthalmologic examination generally permits identification and differentiation of these entities. Although ocular involvement is frequently a harbinger of an unfavorable systemic prognosis, specific drug therapy may be of some benefit in arresting disease in selected individuals. Further advances in the diagnosis and treatment of AIDS-related ocular tumors and infections may improve the quality of life for these patients.


Physical and chemical injuries of the eyes and eyelids. Ocular trauma is not uncommon. Because the tissues associated with visual function are delicate and remarkably specialized, care of ocular injuries is best left to well-trained specialists. Initial care, however, is often simply common sense. Irrigation of chemical burns, sterile techniques, and procedures that salvage tissue are good general principles.


Eyebrow loss, eyelash loss, and dermatochalasis. The eyebrows, eyelashes, and eyelids are important protective structures for the eye and are also of considerable cosmetic value. The dermatologist should understand the available cosmetic and surgical techniques for helping patients with eyebrow loss, eyelash loss, and dermatochalasis.


Increased aggregation with normal surface charge and deformability of red blood cells in children with nephrotic syndrome. Hemorheological risk factors for thromboembolic disease were evaluated in 25 pediatric patients with idiopathic nephrotic syndrome (NS). In patients with increased proteinuria (greater than 100 mg/m2/24 h) red blood cell (RBC) aggregation and plasma viscosity were significantly increased when compared with patients in remission (less than 100 mg/m2/24 h) and with healthy controls. RBC surface charge was normal during increased proteinuria and remission. RBC aggregation correlated positively with plasma viscosity, fibrinogen, alpha 2-macroglobulin, immunoglobulin M, and the degree of proteinuria, and negatively with plasma albumin levels. RBC aggregation showed no correlation to RBC surface charge. Hematocrit and RBC deformability (rheoscope) were similar in both patient groups and in controls. Increased RBC aggregation and plasma viscosity may contribute to the increased risk of venous thromboembolism in NS.


Spontaneously remitting minimal change nephropathy preceding a relapse of Hodgkin's disease by 19 months. A 35-year-old women was diagnosed as suffering from Hodgkin's disease, lymphocytic predominant, based on a biopsy of an enlarged axillary lymph node. She was classified as stage IIA. Subtotal nodal irradiation resulted in a full remission. Ten months later she presented with a full blown nephrotic syndrome. Renal biopsy disclosed minimal change nephropathy. Despite extensive investigation no evidence of a relapse of the lymphoma was found. Whilst undergoing the investigation her proteinuria began to decrease and during the next 5 months it totally disappeared with no specific treatment being administered. Fourteen months after complete cessation of the proteinuria a left parasternal mass appeared. Biopsy confirmed a relapse of Hodgkin's lymphoma. The patient fully responded to chemotherapy and local irradiation. Noticeably, during the relapse and currently after a 3.5 year follow up period the patient has remained free of proteinuria. A review of the literature yielded altogether 14 cases in which the course of minimal change nephropathy did not run in parallel to that of the lymphoma. These are discussed in detail.


Combined liver kidney transplantation in primary hyperoxaluria type I. Prevention of the recidive of calcium oxalate deposits in the renal graft. We report the case of a 31-year-old patient who underwent combined liver and kidney transplantation for primary hyperoxaluria type I. Intensive hemodialysis was performed before the intervention and post-operatively in order to maintain plasma oxalate levels near the normal range. In spite of the correction of the liver enzyme deficiency, oxalate removal from the tissular stores led to prolonged hyperoxaluria, more longer than one year after the transplantation, as already reported. This increased urinary oxalate excretion exposes the renal graft to the risk of recurrence of calcium oxalate deposits and stone formation during a prolonged period. Hemodialysis in the postoperative period and fluid intake allowing a large urine volume might be able to decrease the concentration of urinary oxalate under the critical value of 300 mumol/l, at which supersaturation of urine in respect of calcium oxalate occurs.


Risks and benefits of graft biopsy in renal transplantation under cyclosporin-A. 261 patients who received a kidney transplant under cyclosporin-A immunosuppression were reviewed in order evaluate the benefits and the risks of renal graft biopsies. 240 graft biopsies were performed in 124 of the 261 patients. The biopsy diagnoses were 103x rejection, 90x cyclosporin-A toxicity, 8x acute tubular necrosis, 8x glomerulonephritis, 9x different biopsy results, and 12 cases of normal renal tissue. In 214 cases the clinical course was well explained by the biopsy result. The histological results led to therapeutical changes in 199 cases. 221 of the 240 biopsies were performed without any complications. There was only one biopsy with irreversible and there were 19 biopsies with reversible complications.


Complications of percutaneous renal biopsy: a review of 37 years' experience. Over a period of 37 years we performed renal biopsies 1812 times in 1638 subjects. Tissue adequate for interpretation was obtained in 1593 subjects (88%). Complications occurred in 7% of the total biopsies performed, consisting of gross hematuria lasting for more than 12 hours (3%), pain lasting for more than 12 hours (4%), a palpable hematoma (1%), infection (0.2%), and death (0.2%). Complications were higher when the biopsy yielded unsatisfactory samples (9.5%), although there were no deaths. Complications were not related to age but an elevated BUN appeared to be associated with a higher rate of complications, although this was not statistically significant. Deaths appeared to occur at unpredictable intervals and in retrospect could not have been foreseen.


Renal biopsy diagnosis of acute lymphocytic leukemia. Hyperuricemia, due to inborn errors of metabolism, dehydration, or tumor lysis, may cause renal insufficiency. Hyperuricemia from tumor lysis syndrome in malignancy is usually associated with electrolyte disturbances such as hyperkalemia, hyperphosphatemia or hyper or hypocalcemia. Tumor infiltration into the kidneys can occur, yet this accounts for renal insufficiency in only 1% of patients. This infiltration of tumor cells into the kidneys is usually associated with evidence of malignancy elsewhere as identified by physical exam, radiographic studies, and examination of the peripheral smear or bone marrow. We report an unusual presentation of a child with acute lymphocytic leukemia presenting with acute renal failure, nephromegaly and hyperuricemia without electrolyte disturbances or systemic evidence of tumor elsewhere. We stress the importance of kidney biopsy in order to identify the etiology of the renal failure and hyperuricemia.


Acute effect of dialysate calcium concentration and intravenous vitamin D3 on the secretion of parathyroid hormone in hemodialysis patients. We studied the suppression of intact parathyroid hormone (PTH) in ten patients on chronic hemodialysis using different calcium concentrations of dialysate. Secondly, giving i.v. vitamin D3 at commencement of dialysis we investigated whether 1 alpha (OH)D3 or 1,25(OH)2D3 acutely modifies the responsiveness of the parathyroid gland to the suppressive effect of increased serum calcium. Dialysis with high-calcium dialysate (1.75 mmol/l) reverted the plasma PTH to normal limits. Lower-calcium dialysate (1.5 mmol/l) induced only a partial suppression of hyperparathyroidism. We found no differences in the suppression of hyperparathyroidism whether 1 alpha (OH)D3 or 1,25(OH)2D3 was given at the beginning of the dialysis or not. We conclude that the suppressibility of hyperparathyroidism in dialysis patients can be evaluated by different calcium concentrations of dialysate, and that i.v. vitamin D3 does not acutely modify the responsiveness of the parathyroid gland to the effect of calcium.


Total and regional bone mineral density by dual photon absorptiometry in patients on maintenance hemodialysis. To evaluate bone loss in renal osteodystrophy, we measured total and regional (head, trunk, pelvis, leg and arm) bone mineral density (BMD) by dual photon absorptiometry in 72 patients on maintenance hemodialysis (HD). We also examined the validity of serum carboxy-terminal parathyroid hormone (C-PTH) and intact-PTH as an indicator of secondary hyperparathyroidism. Total BMD correlated inversely with age in female patients (r = -0.57, p less than 0.01), but not in male patients. Female patients older than 50 years were omitted from analysis to exclude the effect of menopause on bone. Among clinical and biochemical parameters, only trunk BMD correlated inversely with the duration of HD (r = -0.26, p less than 0.05). Head, trunk and total BMD correlated inversely with serum alkaline phosphatase, C-PTH and intact-PTH, while pelvis BMD did not. Leg and arm BMD also correlated inversely with serum intact-PTH, but not with serum C-PTH. The serum level of C-PTH correlated positively with the duration of HD (r = 0.40, p less than 0.005), while intact-PTH did not. As compared with 18 control male volunteers aged 25-42 years, trunk, pelvis, leg, arm and total BMD were significantly lower in male patients on HD aged 22-49 years, whereas head BMD did not differ significantly between the two groups. The percent decrease of BMD was most prominent in the trunk (-19.6%, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)


A two-site immunochemiluminometric assay for intact parathyroid hormone and its clinical utility in hemodialysis patients. Measurement of serum parathyroid hormone (PTH) concentrations is complicated by the fact that there are several fragments of the hormone in the circulating as a result of the metabolism of PTH. The best way to study the secretory activity of the parathyroid glands directly may be to measure the biologically active intact PTH molecule. Recently, it has become possible to overcome these limitations by application of the two-site immunoradiometric assay (IRMA) to the measurement of intact PTH. The two-site immunometric technique has been applied to the two-site immunochemiluminescent assay (ICMA) for the measurement of circulating intact PTH. To evaluate the utility of measurements of serum intact PTH by two-site ICMA in hemodialysis patients, two-site ICMA and IRMA were compared in 104 hemodialysis patients. We found a good correlation (r = 0.93) between values obtained by ICMA and by IRMA. Although serum intact PTH by ICMA was significantly suppressed by rising plasma ionized calcium after a session of hemodialysis in 29 patients, mid-region PTH did not show a significant change. This result suggests the intact PTH assay is more suitable for the earlier detection of secondary hyperparathyroidism than the mid-region assay and may be useful for precise assessment of clinical status and response to therapeutic intervention designed to correct the progressive bone disease in hemodialysis patients. We conclude that two-site ICMA for serum intact PTH which could be measured without radioisotopes nor scintillation counter is as useful as IRMA in hemodialysis patients.


Decrease of tumor-like calcification in uremia despite aggravation of secondary hyperparathyroidism: a case report. Extraskeletal pseudotumoral calcifications generally develop in uremic patients with a high calcium x phosphorus (Ca x P) product and severe secondary hyperparathyroidism. In the present case report we describe a chronic hemodialysis patient presenting with a massive calcification of the left shoulder region, severe aluminum (Al) intoxication and moderate hyperparathyroidism. Her initial serum Ca x P product was only slightly elevated: 5.01 mmol2/l2. Under deferoxamine treatment during the subsequent 4 months, Al overload decreased. On the other hand, parathyroid overfunction worsened, as reflected by an increase of the serum immunoreactive parathyroid hormone [1-84] level from initially 690 to 1052 pg/ml (normal, 15-60 pg/ml) and an increase of alkaline phosphatase activity, and plasma calcitriol increased from undetectable to a low-normal value. Predialysis serum total Ca levels decreased rapidly from 2.9 to 2.5 mM but serum P concentrations remained elevated: 1.6-2.5 mM. Unexpectedly, the extent of the periarticular calcification diminished considerably during the same time period. The present observation shows that in a subset of uremic patients with Al overload, pseudotumoral calcifications may regress during Al chelation therapy despite progression of hyperparathyroidism. Since Al may predispose collagen to develop dystrophic or metastatic calcification, it is suggested that this process is reversible by correcting Al intoxication.


Secondary hyperparathyroidism and sonographic evaluation of parathyroid gland hyperplasia in dialysis patients. Ninety-six hemodialysis patients were examined by ultrasonography of the parathyroid glands to study the prevalence of parathyroid gland hyperplasia and to assess the relevance of sonography in the evaluation of secondary hyperparathyroidism. The results were compared with clinical, biochemical and radiological parameters. Thirty-two (33.3%) patients had sonographically enlarged glands. Of them 19 had 1 and 13 had 2 and more enlarged glands. Patients with enlarged glands, compared to those with undetected glands, had a significantly higher frequency of bone and joint pains (65.5% vs 40.6%), radiological features of hyperparathyroid bone disease (in hands 28.1% vs 6.9%, in acromioclavicular joints 37.5% vs 13.6%) and higher levels of intact serum parathyroid hormone (1-84) concentration (52.8 +/- 47.9 pmol/l vs 18.1 +/- 18.0 pmol/l) and serum alkaline phosphatase concentration (260.2 +/- 201.1 U/l vs 129.8 +/- 127.3 U/l). Those with enlarged glands had been on dialysis for a longer period (87.7 +/- 51.0 months vs 62.5 +/- 47.4 months). The severity of secondary hyperparathyroidism increased with the number of enlarged glands. Our study shows that ultrasonography is a useful noninvasive screening method for the evaluation of secondary hyperparathyroidism in patients on hemodialysis and that sonographically enlarged glands may be a measure of the severity of secondary hyperparathyroidism.


Ionized calcium concentration in maintenance hemodialysis patients. Since numerous formulae for "adjusted" total calcium and "calculated" ionized calcium are used in clinical practice, serum total and ionised calcium concentrations were measured in 20 hemodialysis patients with a wide range of serum total calcium and albumin concentrations. Patients were evaluated pre- and post-dialysis to document the effect of pH. Pre-dialysis total calcium varied from 1.70 to 3.17 mmol/L (mean 2.52 +/- 0.08) and a very close correlation between total and ionized calcium was found (r = 0.842; p less than 0.001) with 50.2% being in the ionized form. Dialysis did not alter this relationship despite a significant increase in pH (0.09; p less than 0.01). A normal volunteer group also demonstrated a similar correlation between total and ionized calcium and while the non-ionized calcium concentration was positively and significantly correlated to the serum albumin concentration (r = 0.629; p less than 0.01) this was not the case in the dialysis patients, although the serum albumin range was much greater (18 to 46 g/L). These results suggest that the percentage of total calcium in the ionized form in dialysis patients is not different from the normal population and that minor changes in pH and albumin may not be as important as has previously been believed. While direct measurement is preferable, halving of the total calcium is a simple prediction of the ionized fraction.


Ventricular arrhythmias and the autonomic tone in patients with mitral valve prolapse. The aim of this study was to evaluate a possible relation between the autonomic tone determined by daily urine catecholamine excretion and the incidence of ventricular arrhythmias (VA) in patients with mitral valve prolapse (MVP). The study included 53 patients (31 women and 22 men) aged 19-52 years (mean age 32.7). The diagnosis of MVP was based on medical history, physical examination, and echocardiography. Cardiac arrhythmias were detected by Holter monitoring and classified according to Lown grades. Daily heart rate and duration of corrected QT interval using Basett's formula were also analyzed. Daily urine adrenaline and noradrenaline levels were determined fluorometrically by Von Euler and Lishajko's method. The patients with Lown's grade III-V VA were evaluated with particular consideration. Student's t-test was used for statistical analysis. On Holter monitoring 26 patients showed VA, including 6 with grade I, 11 with grade II, 2 with grade III, 4 with grade IV, and 3 with grade V according to Lown's classification. The remaining 27 patients were free of cardiac arrhythmias. Mean daily heart rate ranged from 54-93 beats/min (73 +/- 8.44, mean +/- SD) and corrected QT from 336-494 ms (411 +/- 37.17). Daily adrenaline and noradrenaline excretion for the whole group of patients were 0.01-16.2 micrograms (2.1 +/- 2.38) and 1.6-31.0 micrograms (13.1 +/- 7.27), respectively, which was within normal range. However, the patients with serious ventricular arrhythmias showed significantly higher daily adrenaline excretion. Individual analysis of two-thirds of patients with ventricular arrhythmias grade III-V showed daily urine noradrenaline levels exceeding mean values for the whole group.(ABSTRACT TRUNCATED AT 250 WORDS)


Influence of serum potassium on the electrocardiographic pattern of left ventricular hypertrophy in primary hyperaldosteronism. Only a few studies deal with electrocardiographic (ECG) signs of left ventricular hypertrophy (LVH) in patients with primary hyperaldosteronism, although it may be presumed that many factors such as arterial hypertension, hypokalemia, increased blood volume, and decreased activity of the renin-angiotensin system can modify LVH pattern in this entity. For that reason, we evaluated ECG signs of LVH in 55 patients with primary hyperaldosteronism hospitalized in our department from 1971 to 1990. These data were compared with age, serum potassium level, plasma renin activity (PRA) and-in 14 patients-with left ventricular mass, measured echocardiographically. We found inverse correlation between serum potassium concentration and the Sokolow-Lyon index: SV1 + RV5/6 (r = -0.47, p < 0.001). Among 24 patients with only abnormal QRS voltage, without ST-T changes suggestive of LVH, 19 (79.2%) had hypokalemia. In multivariate analysis, potassium concentration was the single independent predictor of an abnormal QRS voltage: -0.743, p = 0.01 vs. 0.153 (age), -0.337 (PRA) and 0.454 (LV mass). Our observations suggest that hypokalemia is an important factor influencing an amplitude of QRS complexes and may be responsible for false-positive LVH diagnosis.


Is angiographic ventriculography necessary for the assessment of ischemic patients? A total of 53 patients with a provisional diagnosis of ischemic heart disease and without any clinical evidence of valvular, congenital, or primary muscle heart disease were studied by echocardiography and biplane left ventricular cineangiography. For angiographic ejection fraction analysis, a program developed in our department for use on an Apple Macintosh computer interfaced to a digitizing tablet was employed. Echocardiographic outlines of systolic and diastolic images were traced with a digitizing system on the screen and ejection fractions were calculated by a program incorporated in the echo machine. Good echo windows allowing ejection fraction calculations were present in 35 patients. There was a good correlation between angiographic and echocardiographic ejection fraction (r = 0.7, SEE = 0.09), and wall motion assessment revealed no significant discrepancies between the two image modalities. The remaining 18 patients had poor echo windows, preventing accurate echocardiographic determination of the ejection fraction. However, limited assessment of left ventricular size and wall motion was possible in all patients and allowed the identification of those who had impaired left ventricular function as judged by angiography (angiographic ejection fraction < 35%). We conclude that even in patients with poor echo windows echocardiographic assessment of left ventricular function provides clinical information similar to angiography which should not be considered mandatory for the investigation of ordinary ischemic patients.


QT-interval abnormalities in hypertrophic cardiomyopathy. To examine whether QTc and QTc dispersion across the leads of a surface electrocardiogram (ECG) are different in patients with hypertrophic cardiomyopathy (HCM) compared with normal subjects, we measured QT and calculated QTc in all 12 leads of a surface ECG in 24 patients with HCM and in 20 age- and sex-matched normal control subjects. Maximal QTc was prolonged in HCM patients (465 +/- 24 ms) compared with controls (410 +/- 20 ms) (p < 0.001). QTc dispersion defined as the difference of maximum-minimum QTc was also greater in HCM patients (71 +/- 21 ms) compared with normals (35 +/- 11 ms) (p < 0.001). A correlation was found between the degree of left ventricular hypertrophy expressed by the maximal wall thickness and maximal QTc (r = 0.48, p < 0.02). However, QTc dispersion did not correlate with maximal wall thickness. Thus, patients with HCM show a prolonged QTc (> 440 ms) and increased QTc dispersion compared with normal subjects. In addition, the degree of left ventricular hypertrophy correlates with maximal QTc. The presence of a prolonged QT with increased regional dispersion may be associated with the occurrence of serious ventricular arrhythmia and sudden death in HCM.


Progression of valvular sclerosis in end-stage renal disease treated by long-term peritoneal dialysis. While patients with end-stage renal disease treated by intermittent hemodialysis have frequent and progressive valve disease, nothing is known of the prevalence and course of valvular abnormalities in patients treated with continuous ambulatory peritoneal dialysis (CAPD). Therefore, valves of 24 CAPD patients (ages 55 +/- 11 years; CAPD duration: 29 +/- 28 months) were studied in a prospective echocardiographic and Doppler echocardiographic follow-up analysis over 35 months. Most frequent findings were sclerosis of the aortic annulus (100% at both assessments) and of the anterior mitral valve leaflet (first vs. follow-up assessment: 88 vs. 96%). Sclerosis of the mitral valve annulus (58% vs. 63%), right coronary (54 vs. 63%) and noncoronary (50 vs. 67%) cuspis of the aortic valve and of the posterior mitral valve leaflet (25 vs. 50%) were less frequent but tended to be progressive (p = NS). The moderate form of mitral and aortic valve sclerosis was more frequent than the severe form (p < 0.01 each) at both assessments. Patients with progressive valve disease were older (60 +/- 9 vs. 50 +/- 11 years; p < 0.025) and had a higher frequency angina pectoris than those without a progression (5 vs. 0 patients; p < 0.05). The number of patients with regular sinus rhythm decreased (from 22 to 16; p < 0.03), atrial fibrillation developed in four patients, atrioventricular node rhythm following atrioventricular conduction defect developed in one patient, and atrioventricular conduction defect required implantation of a pacemaker in one patient.(ABSTRACT TRUNCATED AT 250 WORDS)


Single moving dipole obtained from magnetic field of the heart in patients with left ventricular hypertrophy. Magnetocardiograms (MCGs) were recorded by means of a second-derivative SQUID (superconducting quantum interference device) magnetometer in 20 normal subjects and 28 patients with left ventricular overload to analyze the activation sequence of the heart and amplitude of estimated current source. In the normal subjects, the dipole was directed to the left and gradually superiorly 40 ms after the beginning of the QRS wave mainly due to the activation of the left ventricle. In the patients with hypertension, the direction and location of the dipoles were similar to those of the normal subjects, but their dipole moments were increased. In the patients with mitral regurgitation, the dipoles of late QRS were directed more inferiorly than in the normal subjects and their amplitude was increased. In the patients with aortic valve disease, the amplitude of the dipoles was increased markedly and their location was deviated more to the left than the dipoles of the normal subjects. We established the criterion for diagnosis of LVO from the dipole moment of 50 ms of 3.13 x 10(-3) A or more. The sensitivity of this criterion is significantly higher in the diagnosis of left ventricular overload than the electrocardiogram (ECG). The present study shows that the moving dipole method is useful to determine the increased electromotive force in patients with left ventricular overload and that sensitivity in diagnosis of left ventricular overload is increased.


Cardiac pathology in 2007 consecutive forensic autopsies. The incidence of various types of cardiovascular disease was evaluated in 2007 consecutive forensic patients. Cardiovascular deaths accounted for 22.8% of the study patients and atherosclerotic coronary heart disease was the most common type of cardiac disease (18%). Among subjects dying of atherosclerotic coronary disease, sudden death was three times more frequent than acute myocardial infarction. Expected cardiac findings included the incidence of severe coronary atherosclerosis (21%), floppy mitral valves (5%), and congenital bicuspid aortic valves (1%). Major cardiac findings occurred in 32% and minor cardiac findings were found in 40%. Only 17% of hearts were anatomically normal. An unexpected cardiac necropsy finding included the high frequency of myocardial bridges (23%). Unexpected cardiac findings included the low incidence of acute myocarditis (0.6%) and common finding of tunneled epicardial coronary arteries ("myocardial bridges") (23%).


Cardiac tamponade in a patient with Gaucher's disease. Gaucher's disease, a familial inborn error of metabolism associated with hepatosplenomegaly and hypersplenism, was first described by Earnest Gaucher in 1882. By 1959, Hsia found published reports on more than 300 cases. Most reports mentioned the bleeding tendencies of patients with Gaucher's, but show that major hemorrhagic complications are rare. We report a case of hemorrhagic pericarditis with cardiac tamponade in a patient with Type I Gaucher's disease.


Torsade de pointes complicating acute myocardial infarction: the importance of autonomic dysfunction as assessed by heart rate variability. Torsade de pointes is a polymorphic ventricular tachycardia associated with QT-interval prolongation rarely reported to occur in the setting of an acute myocardial infarction. Autonomic dysfunction has been implicated as a major stimulus for the development of this dysrhythmia. We describe the case of an 80-year-old woman who presented with an acute myocardial infarction and progressive QT-interval lengthening. An 89-beat run of torsade de pointes occurred during the time of the peak creatine phosphokinase (CPK) without electrolyte abnormalities or antiarrhythmic therapy. Assessment of autonomic tone using power spectral analysis of two consecutive 24-h Holter recordings was performed indicating that a transient decrease in heart rate variability and increase in sympathetic tone preceded the tachyarrhythmia. This case shows the potential usefulness of heart rate variability analysis as a marker for autonomic dysfunction and arrhythmogenesis, particularly during myocardial ischemia.


Diagnosis of aortic pseudoaneurysm by echocardiography. The diagnosis of pseudoaneurysm of the ascending aorta is of paramount importance because of its propensity to rupture. As the frequency of surgical procedures involving the aortic root and valve increases, an increase in the incidence of aortic pseudoaneurysm may be anticipated. We recently studied a patient who developed pseudoaneurysm of the ascending aorta following repair of a Type I aortic dissection, utilizing a composite graft. Two-dimensional echocardiography with color flow and pulsed Doppler imaging showed a large perigraft cavity communicating with the aorta. Echocardiography provides a safe noninvasive diagnostic tool for the evaluation of the aorta postoperatively and for screening for pseudoaneurysm formation in the follow-up period.


Delayed presentation of a mitral annular perforation complicating Staphylococcus aureus infective endocarditis. This report describes a patient who presented with congestive heart failure secondary to a mitral annular-left atrial fistula. There was a remote history of Staphylococcus aureus endocarditis involving the mitral valve which was treated medically 30 years previously. The sterile fistula was managed surgically with an annuloplasty.


Recurrent myocardial infarction in a postpartum patient receiving bromocriptine. Myocardial infarction in puerperium is infrequently reported. Spasm, coronary dissection, or atheromatous etiology has been described. Bromocriptine has been implicated in several previous case reports of myocardial infarction in the puerperium. Our case (including an inadvertent rechallenge) suggests such a relationship. Although generally regarded as "safe," possible serious cardiac effects of bromocriptine should be acknowledged.


The prevention of atherosclerosis with antioxidants. Recent research findings have suggested a role for pharmacologic as well as nutritional antioxidants in the prevention of atherosclerosis. Data from animal studies as well as cell culture experiments have shown that the drug probucol, which has hypocholesterolemic and antioxidant properties, is able to prevent oxidative modification of low density lipoproteins (LDL). Such modification is now believed to play a major part in the initiation and progression of arterial lesions. Nutrients with antioxidant properties such as vitamins C and E, beta-carotene, and mono-unsaturated fatty acids (when they replace polyunsaturated fatty acids) can reduce the susceptibility of LDL to oxidation. Antioxidant therapy, if proven useful, should be considered an adjunct to lipid-lowering therapy in order to have the greatest impact on coronary heart disease.


Comparison of exercise electrocardiography and dobutamine echocardiography. It is uncertain whether dobutamine echocardiography is a better test than exercise electrocardiography for the detection of coronary disease in patients who can exercise. We compared the hemodynamics, sensitivity, and specificity of these tests in 24 patients, 16 with coronary disease and 8 controls. The tests were performed within six weeks of one another and were interpreted without knowledge of other clinical data. The exercise electrocardiogram was considered abnormal if the patient developed one mm of ST-segment depression, while the dobutamine test (up to 40 micrograms/kg/min) was considered abnormal if the patient developed ST-segment depression or a left ventricular wall motion abnormality. Exercise testing resulted in a higher heart rate (145 +/- 29 vs. 110 +/- 24, p less than 0.001) and blood pressure (176 +/- 31 vs. 148 +/- 24, p less than 0.001). Dobutamine testing was 25% more sensitive than exercise testing (94 vs. 69%, 95% confidence interval for difference is 0 to 50%, p = 0.09), while exercise testing was 38% more specific (88 vs. 50%, 95% confidence interval for difference is -3 to 79%, p = 0.14). We conclude that exercise results in a higher heart rate and blood pressure than dobutamine infusion. Differences in sensitivity and specificity are inconclusive, but indicate that the sensitivity of exercise testing is, at best, equivalent to dobutamine testing, while any increase in specificity with dobutamine testing, compared with exercise testing, would not be clinically significant.