Thyroid hormone and estradiol have overlapping effects on kidney glutathione S-transferase-α gene expression

α-Class GST (Gsta) represents an essential component of cellular antioxidant defense mechanisms in both the liver and the kidney. Estrogens and thyroid hormones (TH) play central roles in animal development, physiology, and behavior. Evidence of the overlapping functions of thyroid hormones and estrogens has been shown, although the molecular mechanisms are not always clear. We evaluated an interaction between TH and estradiol in regulating kidney Gsta expression and function. First, we observed that female mice expressed greater amounts of Gsta compared with males and showed an opposite pattern of expression in TRβ knock-in mice. To further investigate these sex differences, hypothyroidism was induced by a 5-propyl-2-thiouracil diet, and hyperthyroidism was induced by daily T₃ injections. Hypothyroidism increased kidney Gsta expression in male mice but not in female mice, indicating that sex hormones could be influencing the regulation of Gsta by thyroid hormones. To analyze this hypothesis, ovariectomized females were subjected to hypo- and hyperthyroidism, which led to a male profile of Gsta expression. When hypo- or hyperthyroid ovariectomized mice were treated with 17β-estradiol benzoate, we were able to confirm that estradiol was interfering with TH modulation; Gsta expression is increased by T₃ when estradiol is present and decreased by T₃ when estradiol is absent. Using proximal tubule cells, we also showed that estradiol and T₃ worked together to modulate Gsta expression in an overlapping fashion. In summary, 1) the sex difference in the basal expression of Gsta impacts the detoxification process, 2) kidney Gsta expression is regulated by TH in males and females but in opposite directions, and 3) T₃ and estradiol interact directly in renal proximal cells to regulate Gsta expression in females.

Controlling coherence using the internal structure of hard pi pulses

The tiny difference between hard pi pulses and their delta-function approximation can be exploited to control coherence. Variants on the magic echo that work despite a large spread in resonance offsets are demonstrated using the zeroth- and first-order average Hamiltonian terms, for 13C NMR in 60C. The 29Si NMR linewidth of silicon has been reduced by a factor of about 70,00 using this approach, which also has potential applications in magnetic resonance microscopy and imaging of solids.

Generating unexpected spin echoes in dipolar solids with pi pulses

NMR spin echo measurements of 13C in C60, 89Y in Y2O3, and 29Si in silicon are shown to defy conventional expectations when more than one pi pulse is used. Multiple pi-pulse echo trains may either freeze out or accelerate the decay of the signal, depending on the pi-pulse phase. Average Hamiltonian theory, combined with exact quantum calculations, reveals an intrinsic cause for these coherent phenomena: the dipolar coupling has a many-body effect during any real, finite pulse.

Very extended shapes in the A--110 region

High-angular-momentum states in 108Cd were populated via the (64)Ni((48)Ca,4n) reaction at a beam energy of 207 MeV. Gamma rays were detected using the Gammasphere array. A rotational band has been observed with a dynamic moment of inertia and deduced lower limit of the quadrupole moment suggesting a major-to-minor axis ratio larger than 1.8:1, placing it among the most deformed structures identified in any nucleus, to date.

rstand its paraloguekirreact redundantly during embryonic muscle development inDrosophila

The polynucleate myotubes of vertebrates and invertebrates form by fusion of myoblasts. We report the involvement of the Drosophila melanogaster Roughest (Rst) protein as a new membrane-spanning component in this process. Rst is strongly expressed in mesodermal tissues during embryogenesis, but rst null mutants display only subtle embryonic phenotypes. Evidence is presented that this is due to functional redundancy between Rst and its paralogue Kirre. Both are highly related single-pass transmembrane proteins with five extracellular immunoglobulin domains and three conserved motifs in the intracellular domain. The expression patterns of kirre and rst overlap during embryonic development in muscle founder cells. Simultaneous deletion of both genes causes an almost complete failure of fusion between muscle founder cells and fusion-competent myoblasts. This defect can be rescued by one copy of either gene. Moreover, Rst, like Kirre is a myoblast attractant.

Ubiquitous overexpression of a transgene encoding the extracellular portion of the Drosophila roughest-irregular chiasm C protein induces early embryonic lethality

The cell adhesion molecule Rst-irreC is a transmembrane glycoprotein of the immunoglobulin superfamily involved in several important developmental processes in Drosophila, including axonal pathfinding in the optic lobe and programmed cell death and pigment cell differentiation in the pupal retina. As an initial step towards the "in vivo" functional analysis of this protein we have generated transgenic fly stocks carrying a truncated cDNA construct encoding only the extracellular domain of Rst-IrreC under the transcriptional control of the heat shock inducible promoter hsp70. We show that heat-shocking embryos bearing the transgene during the first 8hs of development lead to a 3-4 fold reduction in their viability compared to wild type controls. The embryonic lethality can already be produced by applying the heat pulse in the first 3hs of embryonic development, does not seem to be suppressed in the absence of wildtype product and is progressively reduced as the heat treatment is applied later in embryogenesis. These results are compatible with the hypothesis of the lethal phenotype being primarily due to heterophilic interactions between Rst-IrreC extracellular domain and an yet unknown ligand.

Retrospective study on dengue fatal cases

Immunohistochemical procedure (avidin biotin peroxidase complex) was applied in formalin-fixed and paraffin-embedded tissues obtained from 5 fatal cases of dengue infection associated with encephalopathy. Dengue virus antigen was demonstrated in the cytoplasm of phagocytic mononuclear cells from liver, spleen, and lung. Moreover, dengue viral antigens were here, to our knowledge, first demonstrated in the central nervous system (CNS) and numerous immunolabelled cells were found in brain sections from 3 cases. Extended immunohistochemical studies carried out in 1 case showed virus-positive cells mostly located within Virchow Robin space of medium size and small veins, infiltrating the white and grey matter, and often situated close to neurons displaying apparent cytopathic features. Furthermore, immunostaining for CD68 antigens demonstrated that most CD68+ macrophages and dengue antigen-positive cells share similar morphology and localization, suggesting a unique identity for at least part of these cells. Since in dengue fever, virus replicates mostly in cells of macrophage lineage, our results seem to indicate that infiltration of virus-infected macrophages could be one of the pathways by which viruses enter the brain in dengue encephalitis. Whether bone marrow-derived infected macrophages and viral-free particles induce CSN lesions through immune, metabolic, and/or direct viral-induced mechanisms will be essential to better understand the pathogenesis and provide new therapeutic strategies for dengue-associated encephalitis. As the evidence of tissue damage was nonspecific, the detection of virus antigen by immunoperoxidase technique appeared to be highly reliable for dengue diagnosis.

[Cardiac changes in children with AIDS]

PURPOSE

To describe the cardiac findings in children with AIDS, the follow-up with treatment and the correlation between clinical and pathological features.

METHODS

We studied prospectively 25 children with clinical-laboratorial diagnosis of AIDS, ages between 3 months and 11 years, even those without cardiac symptoms. We classified the signs of AIDS following that of CDC-Atlanta 1994. Eight children died and it was done necropsy in six with macro and microscopic examinations.

RESULTS

Fifteen cases had already complications of AIDS and were classified as C2 and C3, 5 as B2, 3 B1 and 2 as A1. Beside the symptoms related to the disease and infections we found signs of congestive heart failure III and IV (NYHA) in 5 children, pericardial effusion in 5, (one of them had cardiac tamponade). In the electrocardiogram (EKG), 8 children had repolarization abnormalities. In 1st echocardiogram (ECHO) we found some features of dilated myocardiopathy in 8 (6 were asymptomatic) 5 of those had pericardial effusion, one child had huge amount of pericardial liquid and also increased measures of intraventricular septum and posterior wall of left ventricle by ECHO and confirmed by necropsy examination. All cases of diagnosis of myocardiopathy received treatment with captopril and 4 also received furosemide and digoxina. Even under oral treatment three of them had deterioration of heart failure but after combined anti-retroviral drugs they showed better cardiac functions. From the six necropsied cases, two had increased heart weight without myocarditis, one had toxoplasma pancarditis and other one had fibrocalcic vasculopathy.

CONCLUSION

We found several assymptomatic cases already with decreased ventricular function. Some worsened of heart failure even under apropriate treatment and showed better cardiac index after combined anti-retroviral drugs.

[Rheumatic heart disease and infective endocarditis in a patient with acquired immunodeficiency syndrome]

A 36-old-woman was admitted with an infectious syndrome, respiratory insufficiency and vasculitis. There was a history of chronic intravenous drug abuse, sexual promiscuity and rheumatic heart disease. She had HIV positive tests. The vasculitis and heart failure worsened and the patient died of stroke. At autopsy it was found histologic evidence of AIDS, rheumatic heart disease with Aschoff nodes, infective endocarditis with cerebral abscesses and thalamic infarction.

When neurobiology and genetics meet: the study of visual system development in Drosophila melanogaster

The visual system of Drosophila melanogaster is an exceptionally well suited model to study the molecular and genetic mechanisms underlying inter- and intracellular signalling during nervous system development. This review highlights some of the recent advances in this field, that show not only the power of the combined neurobiological and genetical approaches in shedding new light into long standing questions regarding nervous system development but also uncover a striking evolutionary conservation, at the molecular level, of the basic developmental pathways and signal transduction cascades underlying metazoan ontogenesis.

Restricted expression of the irreC-rst protein is required for normal axonal projections of columnar visual neurons

The 104 kDa irreC-rst protein, a member of the immunoglobulin superfamily, mediates homophilic adhesion in cell cultures. In larval optic chiasms, the protein is found on recently formed axon bundles, not on older ones. In developing visual neuropils, it is present in all columnar domains of specific layers. The number of irreC-rst-positive neuropil stratifications increases until the midpupal stage. Immunoreactivity fades thereafter. The functional importance of the restricted expression pattern is demonstrated by the severe projection errors of axons in the first and second optic chiasms in loss of function mutants and in transformants that express the irreC-rst protein globally. Epigenesis of the phenotypes can be explained partially on the bases of homophilic irreC-rst interactions.

[Clinicopathologic correlation in 50 cases of acquired immunodeficiency syndrome. Retrospective study]

PURPOSE

To analyze myocardial abnormalities in patients of acquired immunodeficiency syndrome with clinical and pathological correlation.

METHODS

We selected 50 cases, retrospectively, age ranged from 3 months to 40 years, all of them had myocardial changes and the data of clinical records fulfilled our protocol. Cases of others cardiac diseases were not included.

RESULTS

The pathological findings were: myocarditis in 33 (11 had severe myocarditis) and degenerative hystological lesions in 17. The etiologic agents detected were: Toxoplasma in 11, Cryptococcus in 7 and Cytomegalovirus in 3. In 12 cases we could not find any agent. In 15 cases occurred others lesions: endocarditis, pericarditis and sarcoma of Kaposi. It was noted tachycardia in 15 cases, decrease of heart sounds in 12, arterial hypotension in seven, systolic murmur in 8, galop rhythm in 7, pericardial friction rub in 3, arrhythmia in 2. Four patients had congestive heart failure. The EKG showed sinus tachycardia in 18, ST and T changes in 10, low voltage in 5, ST segment elevation in 5 and extrasystoles in 3 cases. The echocardiogram findings were: pericardial effusion in 9 cases and 9 had ventricular dysfunction.

CONCLUSION

The cardiac lesions were very important even in patients without clinical signals. We need others prospective studies with viral identification trying to detect specific lesions of HIV.

The irregular chiasm C-roughest locus of Drosophila, which affects axonal projections and programmed cell death, encodes a novel immunoglobulin-like protein

The axonal projection mutations irregular chiasm C of Drosophila melanogaster comap and genetically interact with the roughest locus, which is required for programmed cell death in the developing retina. We cloned the genomic region in 3C5 by transposon tagging and identified a single transcription unit that produces a major, spatially and temporally regulated mRNA species of approximately 5.0 kb. Postembryonic expression is strong in the developing optic lobe and in the eye imaginal disc. The gene encodes a transmembrane protein of 764 amino acids with five extracellular immunoglobulin-like domains and similarity to the chicken axonal surface glycoprotein DM-GRASP/SC1/BEN. Both known irreC alleles reduce the level of transcription, whereas the roughestCT mutation disrupts the intracellular domain of the protein.

A prospective, placebo-controlled, randomized trial of intravenous streptokinase and angioplasty versus lone angioplasty therapy of acute myocardial infarction

BACKGROUND

The value of routine administration of intravenous thrombolytic agents during percutaneous transluminal coronary angioplasty (PTCA) therapy of acute myocardial infarction (MI) has not been determined. Therefore, we prospectively randomized 122 patients with evolving MI to PTCA therapy with or without adjunctive intravenous streptokinase therapy.

METHODS AND RESULTS

Patients with ECG ST segment elevation who presented within 4 hours of symptom onset, had no contraindication to thrombolytic therapy, and were not in cardiogenic shock were enrolled. They were treated immediately with intravenous heparin (10,000 units) and oral aspirin (325 mg) and randomized to treatment with placebo or streptokinase (1.5 M units) administered intravenously over 30 minutes. Patients then were taken immediately to the catheterization laboratory, and those with suitable coronary anatomy underwent immediate PTCA. Subsequent clinical course, serial radionuclide ventriculography, and 6-month repeat angiography were analyzed. A total of 106 patients were treated with PTCA. Use of PTCA was similar for placebo (92%) and streptokinase (83%) groups. Angioplasty was successful in 95% of patients, with no difference in placebo (93%) and streptokinase (98%) groups. Serial radionuclide ventriculography demonstrated no difference in 24-hour (52 +/- 12% versus 50 +/- 12%) or 6-week (51 +/- 12% versus 51 +/- 13%) ejection fraction values for placebo and streptokinase groups, respectively. Contrast ventriculography demonstrated improvement in immediate (54 +/- 12%) versus 6-month (60 +/- 15%, p < 0.05) values for the overall group. No differences in 6-month values were present (58 +/- 15% versus 62 +/- 15%, p = NS) for placebo and streptokinase groups, respectively. Coronary angiography was performed in 75% of the 90 patients eligible for restudy. Arterial patency was 87% at 6 months, and coronary restenosis was present in 38% of patients. No differences in chronic patency or restenosis were detected for the two treatment groups. Although adjunctive intravenous streptokinase therapy did not improve outcome, it did complicate the hospital course. Hospitalization was longer (9.3 +/- 5.0 versus 7.7 +/- 4.4 days, p = 0.046) and more costly ($25,191 +/- 15,368 versus $19,643 +/- 7,250, p < 0.02). Transfusion rate was higher (39% versus 8%, p = 0.0001) and need for emergency coronary bypass surgery was greater (10.3% versus 1.6%, p = 0.03) for the streptokinase-treated patients.

CONCLUSIONS

Adjunctive intravenous streptokinase therapy does not enhance early preservation of ventricular function, improve arterial patency rates, or lower restenosis rates after PTCA therapy of acute MI. Hospital course is longer, more expensive, and more complicated. For these reasons, PTCA therapy of acute MI should not be routinely performed with adjunctive intravenous streptokinase therapy.

Outcome of patients with acute myocardial infarction who are ineligible for thrombolytic therapy

OBJECTIVE

To determine what proportion of patients with acute myocardial infarction are not eligible for thrombolytic therapy and to assess their natural history.

DESIGN

Retrospective chart review.

SETTING

A large community-based hospital.

PATIENTS

All patients with acute myocardial infarction hospitalized during a 27-month period.

MEASUREMENTS

Of 1471 patients with acute myocardial infarction, 230 (16%) received thrombolytic therapy according to the protocol and an additional 97 (7%) received nonprotocol thrombolytic therapy, primary coronary balloon angioplasty, or both because of contraindications. The other 1144 patients (78%) did not receive reperfusion therapy.

MAIN RESULTS

The patients who did not receive thrombolytic therapy were older, more likely to be women, and more likely to have a history of hypertension, previous myocardial infarction, or chronic angina (all comparisons, P less than 0.002). An average of 1.9 reasons for exclusion were identified per patient among the ineligible patients. Mortality was fivefold higher among ineligible patients (19%; Cl, 16% to 21%) than among protocol-treated patients (4%; Cl, 1% to 6%) (P less than 0.001). In-hospital mortality rates for excluded patients were 28% (Cl, 23% to 32%) in elderly patients (age, greater than 76 years; n = 396); 29% (Cl, 23% to 35%) in patients with stroke or bleeding risk (n = 209); 17% (Cl, 14% to 20%) in patients with delayed presentation (greater than 4 hours after the onset of chest pain; [n = 599]); 14% (Cl, 11% to 16%) in patients with an ineligible electrocardiogram (ECG) (n = 673); and 26% (Cl, 21% to 32%) in patients with a miscellaneous reason for exclusion (n = 243). Independent predictors of increased mortality were: age greater than 76 years, stroke or other bleeding risk, ineligible ECG, or the presence of two or more exclusion criteria.

CONCLUSIONS

Thrombolytic therapy is currently used in the United States for only a minority of patients with acute myocardial infarction: those who have low-risk prognostic characteristics.

Dengue: neuropathological findings in 5 fatal cases from Brazil

Neuropathological examination of 5 patients with dengue who died of shock in Rio de Janeiro during an outbreak in summer 1987, showed nonspecific lesions (edema, vascular congestion, hemorrhagic foci and perivascular lymphocytic infiltrates). In one case with delayed marked neurological symptoms, several foci of perivenous demyelination were observed. Neurological manifestations are various and not uncommon in dengue, but their anatomical substratum is not known. An immunopathological mechanism has been postulated in some cases but has never been demonstrated morphologically. The perivenous leukoencephalitis observed in one of our cases could represent the morphological substratum of such an immunological mechanism.

Genetic and developmental analysis of irreC, a genetic function required for optic chiasm formation in Drosophila

Irregular chiasm C (irreC) is an X-linked genetic function necessary for the correct projection of visual fibers in the optic chiasms of Drosophila optic ganglia. In addition to a severe disorganization of the inner optic chiasm irreC mutants display a subtle phenotype in the outer optic chiasm, in which some bundles of axons that leave the posterior equatorial part of the lamina on their way to the anterior medulla take a long detour before eventually finding their specific targets in the medulla neuropile. Deletion and recombination mapping of two irreC alleles (one P-element induced, the other associated with an inversion) have yielded a precise cytogenetic location in 3C4-5. A complex complementation pattern between roughest (rst) and irreC alleles indicates that both genetic functions are structurally and/or functionally closely interrelated. Flies in which the irreC locus is completely deleted by overlapping deficiencies are viable and their defects in the optic chiasms are similar to those seen in the two alleles. The defects in the outer and inner optic chiasms are not epigenetically connected and mosaic analyses have shown them to be independent from the genotype of the compound eye. Although the larval visual nerve looks normal, we have found that in the optic lobes of irreC mutants a group of early differentiating larval neurons is misplaced, suggesting a pioneering function of these cells during organization of the outer optic chiasms.

Early hospital discharge after percutaneous transluminal coronary angioplasty

To determine the safety and efficacy of early hospital discharge after percutaneous transluminal coronary angioplasty (PTCA), 100 patients were studied prospectively. A telemetry observation unit was established to monitor patients having uncomplicated procedures. A total of 170 lesions were dilated, with a procedural success rate of 96% and a clinical success rate of 91%. There were no deaths or patients who required emergency bypass surgery. Four patients developed abrupt vessel closure in the catheterization laboratory. No major complications developed in the telemetry observation unit or after discharge. Patients with high-risk lesion morphology, based on the American College of Cardiology/American Heart Association Task Force guidelines, tended to have a lower success rate and more procedural complications. Coronary dissections were angiographically detected in 33 patients and stratified into 6 types. To reduce possible adverse sequelae, all patients with complex dissections were triaged in the catheterization laboratory to an in-patient monitored unit for additional management. Accordingly, 20 patients were admitted to an in-patient unit for extended observation. Excluding 4 patients with myocardial infarction, 75% (12 of 16) were discharged the next day. Initial experience with early discharge suggests that under proper conditions the procedure is safe and effective. Patients with complex coronary dissections who are at high risk for abrupt vessel closure can be promptly identified after dilatation and triaged to an appropriate monitoring area. Early discharge after PTCA offers more efficient use of hospital facilities and the opportunity to reduce hospital costs.

Physical and functional definition of the Drosophila Notch locus by P element transformation

Notch is a developmentally regulated locus which controls the differentiation of various Drosophila tissues, among them the embryonic nervous system. Molecular analysis has suggested that Notch is defined by an approximately 40-kb transcription unit which is spliced into a 10.2-kb mRNA composed of nine exonic regions and coding for a 2703-amino acid long transmembrane protein that shows homology to the mammalian epidermal growth factor. Here, we define the 5' end of the transcription unit and determine the sequences deleted in a Notch mutation involving the 5' nontranscribed region. Using a Notch cosmid vector we demonstrate by P element-mediated transformation that all sequences necessary for Notch function are confined in an approximately 40-kb long genomic region. cDNA sequences are used to construct a 15-kb "minigene" which lacks most, but not all, introns and its functionality is also tested by P element transformation. We show that, unlike the cosmid vector which is capable of rescuing completely all Notch mutations, only certain phenotypes can be rescued by the "minigene." The functional implications of our findings are discussed.

Gastrointestinal and cardiac response to low-calorie semistarvation diets

Effects of low-calorie semistarvation diets on gastrointestinal and cardiac organ systems were studied. Male Sprague Dawley rats were divided into two groups, Group I, control (C) and Group II, semistarvation (SS), and maintained on a diet designed after low-calorie modified-fasting regimens in popular use. C animals consumed this diet ad libitum; SS animals received 23% of the total calories of C but the same ratio of calories from protein, carbohydrate, and fat and the same quantity and quality of all essential nutrients. Final weights of total body, heart, liver, and small intestine were lower in SS than in C animals. Protein depletion in SS compared with C animals was evident for heart, pancreas, and intestinal mucosa. Unless aggressively supplemented, low-calorie SS diets may deplete protein stores of the gastrointestinal organs of digestion and absorption and contribute to decrease in body nitrogen stores, specifically cardiac muscle.

Hemorrhage vs rethrombosis after thrombolysis for acute myocardial infarction

To determine whether or not the timing of heparin infusion affects either bleeding or reocclusion following intracoronary streptokinase for acute myocardial infarction, heparin was infused immediately after streptokinase in 89 patients and was delayed for 12 hours in the subsequent 93. Bleeding occurred in 22 immediate-heparin patients and was major in five (one fatal); there were 14 hemorrhages in the delayed-heparin group, all minor. At discharge, reocclusions were observed in 18% (12/68) of immediate-heparin patients, and 11% (3/27) of the latter. Bioassayed fibrinogen levels displayed sustained depression regardless of bleeding for 20 hours after streptokinase; however, defibrinogenation measured by immunoassay was much less striking. This suggests that high levels of fibrinogen degradation products spuriously affect the bioassay of fibrinogen. We conclude that bleeding is related to the anticoagulant effects of fibrinogen degradation products interacting with heparin, and may be largely independent of hypofibrinogenemia. Delaying heparin for 12 hours may decrease the risk of bleeding while little affecting the risk of reocclusion.

The influence of infarction site and size on the ventricular response to coronary thrombolysis

To test the hypothesis that myocardial infarction (MI) size rather than location determines the ventricular response to reperfusion, we studied 69 patients receiving intracoronary streptokinase within five hours of chest pain onset who displayed sustained reperfusion at 8.4 +/- 3.4 (SD) days. Twenty reperfusion failures served as controls. There were 31 patients with anterior MIs, 18 of which were estimated to be large based on an ejection fraction (EF) at reperfusion of less than 50%; 14 of 38 patients with inferior MIs also had large MIs. The EF increased at follow-up by 6.4% +/- 2.6% in patients with large anterior MIs and by 8.2% +/- 2.5% in those with large inferior MIs; in contrast, it increased by only 1.8% +/- 2.6% in patients with small anterior MIs and significantly decreased by 5.8% +/- 1.9% in patients with small inferior MIs. Six controls with large MIs (four anterior) displayed no change in EF; in 14 with small MIs (ten inferior), it fell slightly. There were no significant group differences in the number of diseased vessels, residual stenosis, or collaterals. It is concluded that MI size, not site, largely determines the ventricular functional response to early reperfusion; thus, patients with inferior MIs cannot be disqualified on this basis alone for thrombolytic therapy.

Sequence of mechanical, electrocardiographic and clinical effects of repeated coronary artery occlusion in human beings: echocardiographic observations during coronary angioplasty

The direct manipulation of coronary blood flow to induce regional myocardial ischemia has been almost entirely limited to experimental animal models. Thus, the detection of ischemia-induced left ventricular dysfunction in human subjects has been generally limited to observations made under conditions of diagnostic loading or during spontaneous clinical events. Percutaneous coronary angioplasty requires repeated interruptions of coronary blood flow for periods as long as 1 minute. The resulting appearance of or increase in ischemia-produced changes in myocardial function were detected by two-dimensional echocardiography in 18 patients undergoing angioplasty of 22 coronary stenoses. Accordingly, left ventricular contraction was studied during 52 episodes of regional coronary blood flow interruption and reperfusion in the process of inflating and deflating the angioplasty balloon. Before angioplasty, left ventricular wall motion was normal in 14 patients. There was mild anteroapical hypokinesia in two patients, anteroapical akinesia in one and mild inferior hypokinesia in one. Balloon inflations repeatedly produced new or increased wall motion abnormalities in the distribution of the instrumented coronary artery in 19 (86.4%) of the 22 procedures, but did not alter wall motion during angioplasty of one left circumflex artery lesion, one highly collateralized left anterior descending artery stenosis and one left anterior descending stenosis that had already caused severe anteroapical dyssynergy. Hypokinesia, usually rapidly progressing to dyskinesia, began 19 +/- 8 seconds (mean +/- SD) after coronary occlusion. Wall motion began to normalize 17 +/- 8 seconds after reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemorrhage and the products of fibrinogen digestion after intracoronary administration of streptokinase

Hemorrhage was prospectively identified in 26 of 116 consecutive patients (23%) who were receiving intracoronary streptokinase for occlusive coronary thrombi producing infarction. Bleeding was not influenced by the dose of streptokinase or the method of cardiac catheterization. Before treatment, prothrombin time and partial thromboplastin time were normal in both bleeders and nonbleeders. Fibrinogen levels measured by bioassay after streptokinase (mean +/- SEM) were 62 +/- 29 mg/dl in patients with major bleeding, 111 +/- 26 mg/dl in patients with minor bleeding, and 109 +/- 13 mg/dl in nonbleeders (p = NS). The regression slope b calculated from poststreptokinase fibrinogen time-concentration data in 71 patients was 4.7 mg/dl/hr. However, mean fibrinogen concentrations calculated at sequential 5 hr intervals revealed no net regeneration for the first 20 hr after thrombolysis. The apparent fibrinogen regeneration rate was less than normal (31 mg/kg/day) for more than 10 hr but subsequently increased to 94 +/- 10 mg/kg/day by the second day. The initial apparent latency of fibrinogen regeneration paralleled the sharp rise in fibrinogen degradation products, which began to decline after 20 hr of treatment but remained elevated well into the second day. Because of their anticoagulant effects, these products may interfere with the fibrinogen assay, causing spuriously low results. Thus, whether the early delay in fibrinogen regeneration is real or simply a reflection of the effects of fibrinogen degradation products on the bioassay, it signals the time for caution in initiating systemic heparin therapy.

Intracoronary streptokinase in clinical practice

The candidacy for streptokinase (SK) infusion was studied in 95 patients displaying ECG evidence of acute or impending infarction who were catheterized within 5 hours of the onset of chest pain. Intracoronary SK was administered to 84 patients in whom occlusions of the infarct-related vessel were identified, with early recanalization having been achieved in 74 (88%). Because of completeness of studies, a data base of 72 patients was employed for further analysis. Recanalization was sustained at follow-up in 45 of 55 patients (82%). Spontaneous thrombolysis was demonstrated at follow-up in five patients (8%) initially resistant to SK, and rethrombosis occurred in 10 patients (18%). Preservation of R waves relative to Q wave depth was limited to patients with less than 90% residual stenosis. Eight of nine patients with continuing thrombolysis and patients with recanalized occlusions of the left anterior descending coronary artery displayed more impressive increases in mean (+/- SEM) ejection fraction (47% +/- 4% to 53% +/- 5% [p less than 0.05], and 47% +/- 3% to 52% +/- 5, respectively). The ejection fraction also increased significantly in 15 patients with pre-SK values of less than 50% (41% +/- 2% to 48% +/- 3%; p less than 0.05). Ventricular function deteriorated in SK failures. Reperfusion arrhythmias occurred in 28 of 62 recanalized patients (45%). Minor bleeding tendencies were displayed in 18 of 72 patients (25%). Major hemorrhages, one of which may have been fatal, occurred in four patients (5.6%). Of 84 patients, four (4.7%) died, two of whom were in cardiogenic shock when first seen. In contrast, there were 11 deaths (11.8%) in a consecutive simultaneously enrolled series of 93 control patients with similar entry criteria (p less than 0.05). Two additional SK-treated patients died, 16 and 30 days after treatment, both more than a week after surgical revascularization. It is concluded that SK recanalization is a promising new therapy that may decrease mortality and preserve myocardial function in certain circumstances. Its efficacy in a setting closer to the mainstream of cardiologic practice extends the favorable experience issuing from earlier clinical investigations.

Percutaneous intraaortic balloon counterpulsation. Clinical effectiveness and hazards

Because of its greater ease and rapidity of insertion, the percutaneous intraaortic balloon in many institutions has become the primary method for implementing counterpulsation. We report the results and complications of 113 attempted procedures in a variety of clinical settings. We had a high (93.8 percent) insertion success rate. However, our 18.6 complication rate was similar to the experience reported for the surgical method of insertion. Thus, the original anticipation of reduced complications with this method has not been realized in this and other recent reports.

The relative resistance of normal young women to ethanol-induced myocardial depression

In contrast to previous reports from our own laboratory utilizing systolic time intervals (STI) and by others using ultrasound, no evidence of acute myocardial depression was observed in response to an ethanol (ETOH) dose of 1.25 ml/lb consumed over a period of 60 minutes by 6 young women (22.7 ± 7 years; 133 ± 6 lbs) who were monitored for 3 hours thereafter. Specifically, there was no significant change in fractional shortening (%ΔD), ejection frac tion, or mean circumferential fiber shortening velocity. Cardiac index and stroke index also remained stable, although heart rate increased ( P < 0.005) and systolic and diastolic blood pressure fell ( P < 0.01 and 0.25 respectively).

To examine further this unanticipated cardiac resistance to ETOH, we re- examined the sex-specific difference of STI response to acute ETOH exposure in a previously reported group of 32 normal subjects (20 men and 12 women). Significant increases in PEP, PEPI, ICT, and PEP/LVET ( P < 0.005, 0.005, 0.005, and 0.001 respectively) were observed in men only. Because we have previously observed that chronic ETOH consumption blunts acute myocardial depression, and because only 1 of 7 STI subjects historically consuming the least ETOH (< 1 oz/day) was a woman, STIs, were reassessed only in those subjects with a chronic consumption of 1 or more oz/day (14 men and 11 women). Myocardial depression as estimated by an increased ICT ( P < 0.05) and PEP/ LVET (P < 0.02) was again observed in men only.

We concluded that women are less susceptible than men to acute ETOH induced myocardial depression, as has recently been suggested for chronic ETOH consumption as well.

Limitations of exercise testing in critical left coronary artery disease

Exercise testing was evaluated in 51 patients with critical left coronary artery disease (LCA) documented by coronary arteriography within two weeks of their bicycle ergometer (26 patients) or treadmill (25 patients) electrocardiographic study. Adequate tests, as defined by the patient having reached 85% of predicted maximum heart rate, were achieved in only 16 patients on the ergometer (62%) and in 21 (84%) on the treadmill. Nevertheless mean maximum double product (220 vs 232) and mean exercise time (4.6 min vs 5.0 min.) were similar (p:NS). The sensitivity for ergometry and treadmill testing was 75 and 62% respectively. If however we include those negative studies in which for various reasons patients were unable to achieve 85% of their predicted maximal heart rate (i.e., inadequate studies), sensitivity was only 46 and 52% respectively. Thus a sizable group of patients with critical LCA disease cannot adequately perform exercise tests especially on the ergometer; and over half of all such patients studied will be found for one reason or another to respond negatively, regardless of exercise protocol.

Reassessment of Q waves in left bundle branch block

This study disputes a number of recent reports claiming that abnormal Q waves or a QS configuration in inferior leads (II, III and AVF) coexisting with left bundle branch block is highly suggestive of, and indeed specific for, myocardial infarction. Five patients reported herein demonstrate disappearance of Q waves in inferior leads on spontaneous reversal of LBBB to normal conduction. This necessitates the conclusion that these Q waves represent a postdivisional conduction variant most closely equivalent to left anterior fascicular block coexisting with predivisional LBBB. Absence of inferior R waves in the five patients demonstrating LBBB is explicable by as little as a 20 msec conduction delay in the posterior fascicle coexisting with a higher grade conduction defect in the anterior fascicle. It is concluded that LBBB with a QS configuration in II, III and AVF cannot be considered diagnostic of inferior wall infarction since it regularly results from impaired conduction of the left anterior and possibly the left posterior fascicle (to a lesser extent), which may be reversible.