Tumor-induced immune dysfunction: the macrophage connection

Although macrophages (Mphis) mediate tumor cytotoxicity, display tumor-associated antigens, and stimulate antitumor lymphocytes, cancer cells routinely circumvent these host-mediated immune activities, rendering the host incapable of mounting a successful antitumor immune response. Evidence supporting a direct causal relationship between cancer and immune dysfunction suggests that the presence of neoplastic tissue leads to immunologic degeneration. Furthermore, substantial data demonstrate that tumor growth adversely alters Mphi function and phenotype. Thus, although Mphis can serve as both positive and negative mediators of the immune system, the importance of Mphis in tumor-induced immune suppression remains controversial. This review focuses on the evidence that tumor-derived molecules redirect Mphi activities to promote tumor development. Tumors produce cytokines, growth factors, chemotactic molecules, and proteases that influence Mphi functions. Many tumor-derived molecules, such as IL-4, IL-6, IL-10, MDF, TGF-beta1, PGE2, and M-CSF, deactivate or suppress the cytotoxic activity of activated Mphis. Evidence that tumor-derived molecules modulate Mphi cytotoxicity and induce Mphi suppressor activity is presented. This information further suggests that Mphis in different in vivo compartments may be differentially regulated by tumor-derived molecules, which may deactivate tumor-proximal (in situ) Mphi populations while concurrently activating tumor-distal Mphis, imparting a twofold insult to the host's antitumor immune response.

Mechanisms of streptozotocin- and alloxan-induced damage in rat B cells

In studies to evaluate possible inhibitors of the B-cell toxin, streptozotocin, the superoxide scavenger, superoxide dismutase, did not prevent or reduce the toxic effects of streptozotocin as determined by loss of insulin secretion from rat pancreatic B cells in monolayer culture. However, 1,1-dimethyl urea, a scavenger of the hydroxyl radical, did afford significant protection. Both scavengers diminished the cytotoxic effects of alloxan. The inhibitors of poly (ADP-ribose) synthetase, 3-aminobenzamide and nicotinamide, also were effective in attenuating alloxan- and streptozotocin-induced B-cell toxicity. Tests of the hydroxyl-scavenging ability of the three streptozotocin antagonists revealed that 3-aminobenzamide, nicotinamide and 1,1-dimethyl urea were effective scavengers of this free radical. Conversely, 1,1-dimethyl urea, although not as potent as 3-aminobenzamide or nicotinamide, was found to inhibit poly (ADP-ribose) synthetase. These data indicate that these chemicals most likely attenuate alloxan-induced toxicity by scavenging the hydroxyl radical and diminish streptozotocin-induced toxicity by inactivation of the poly (ADP-ribose) system.

Manipulation of avidity to improve effectiveness of adoptively transferred CD8(+) T cells for melanoma immunotherapy in human MHC class I-transgenic mice

The adoptive transfer of tumor-reactive CD8(+) T cells into tumor-bearing hosts provides an attractive alternative to vaccination-based active immunotherapy of melanoma. The development of techniques that result in the preferential expansion of tumor-reactive T cells is therefore of great importance. In this study, we report the generation of HLA-A*0201-restricted CD8(+) T cell populations that recognize either tyrosinase(369-376) or gp100(209-217) from tolerant human class I MHC-transgenic mice by using single amino acid-substituted variant peptides. Low peptide concentration or restimulation with the parent peptide was used to enhance the functional avidity, defined by stimulation of IFN-gamma accumulation, and cross-reactivity of the resulting T cell populations. We found a direct correlation between the ability of a T cell population to respond in vitro to low concentrations of the precise peptide expressed on the tumor and its ability to delay the outgrowth of B16 melanoma after adoptive transfer. Surprisingly, we found that some T cells that exhibited high functional avidity and were effective in controlling tumor outgrowth exhibited low structural avidity, as judged by MHC-tetramer staining. Our results establish strategies for the development and selection of CD8(+) T cell populations that persist despite peripheral tolerance, and that can control melanoma outgrowth. Furthermore, they support the use of human MHC class I-transgenic mice as a preclinical model for developing effective immunotherapies that can be rapidly extended into therapeutic settings.

Poly(adenosine diphosphate-ribose) polymerase: the distribution of a chromosome-associated enzyme within the chromatin substructure

The distribution of a chromatin-bound, nuclear protein modifying enzyme, poly (adenosine diphosphate-ribose) polymerase, and its product, poly(ADP-ribose), among various fractions of sheared and nuclease-digested HeLa cell chromatin has been examined. Epichlorohydrin-tris(hydroxymethyl)aminomethane-cellulose and glycerol gradient fractionation of solubilized chromatin indicated that poly(ADP-ribose)polymerase activity was associated primarily with the template active regions (euchromatin), whereas the transcriptionally inert chromatin fractions were found to contain relatively low levels of ADP-ribosylating activity. When isolated HeLa cell nuclei were digested in situ with micrococcal nuclease and the resultant chromatin was fractionated into nucleosome monomers (v bodies) and oligomers by sucrose gradient centrifugation, only material sedimenting faster than the 11S monomers was found to contain appreciable poly(ADP-ribose) polymerase activity. If, on the other hand, isolated HeLa cell nuclei were first incubated with labeled NAD, the substrate for poly(ADP-ribose) polymerase, prior to the preparation and fractionation of nuclease-digested chromatin, it was found that those chromatin fractions which possess significant poly(ADP-ribose) polymerase activity (nucleosome oligomers) are relatively deficient in the labeled product of this enzyme, and that a considerable portion of the homopolymeric product is ultimately associated with the 11S v bodies. Additional evidence is presented which indicates that the absence of nucleosome monomer-associated poly(ADP-ribose) polymerase activity is not due to the absence of a suitable acceptor on these structures, and that the activity of this enzyme within the chromatin is most probably dependent upon the physical integrity of the oligomeric structures themselves.

Role of laparoscopy in the evaluation of abdominal trauma

This prospective study was designed to determine if laparoscopy is a safe and accurate method for abdominal evaluation in the trauma patient. Thirty-two patients who presented with blunt or penetrating trauma and who were scheduled for celiotomy based on clinical evaluation constituted the study group. The patients underwent diagnostic laparoscopy prior to exploratory celiotomy. One of 6 (16%) patients with blunt abdominal trauma and 5 of 26 (19%) patients with penetrating abdominal trauma had significant injuries that were found at the time of operation but not visualized during laparoscopy. The missed injuries involved the liver, pancreas, stomach, duodenum, small bowel, small bowel mesentery, ureter, and urinary bladder. The correlation between the laparoscopist and the trauma surgeon as to the need to perform a celiotomy was 97%. Complications occurred in 2 of 32 patients. Eleven patients with anterior abdominal penetrating injuries had no evidence of penetration of the abdominal cavity at laparoscopy, and had no evidence of injury at celiotomy. We concluded that (1) there are areas within the abdominal cavity that cannot be accurately visualized with laparoscopy; (2) the evaluation of penetration of the peritoneal cavity from anterior penetrating injury appears to be accurate; (3) a number of injuries were not identified; and (4) further investigation of this procedure for the evaluation of abdominal trauma is required to assess its safety and accuracy.

The reliability of color duplex ultrasound in diagnosing total carotid artery occlusion

BACKGROUND AND PURPOSE

Color duplex ultrasound has been advocated as an alternative to arteriography before carotid endarterectomy. However, one limitation of color duplex ultrasound is that it sometimes fails to differentiate high-grade stenosis from total carotid occlusion. This study was done to determine (1) the accuracy of carotid duplex ultrasound in diagnosing total carotid occlusion, and (2) when angiography is necessary.

PATIENT POPULATION AND METHODS

Carotid duplex ultrasound and angiography results were compared for 520 carotid arteries, and 103 of these had a duplex diagnosis of total carotid occlusion or suspected almost total-to-total occlusion. The diagnosis of total carotid occlusion was primarily based on the absence of flow in the internal carotid artery as visualized on B-mode imaging for at least 1 inch beyond the bifurcation (optimal study). If the internal carotid artery was not optimally seen beyond the bifurcation, but secondary criteria were present, such as dampening of the common carotid signal and internalization of the external carotid artery, a diagnosis of suspected subtotal to total occlusion was made (limited study).

RESULTS

In the optimal studies, 91 arteries had total carotid occlusions and of these, 87 were confirmed by angiography. The accuracy of carotid duplex ultrasound in diagnosing total carotid occlusion was 97% with a positive predictive value of 96%, negative predictive value of 98%, sensitivity of 91%, and specificity of 99%. Twelve arteries were diagnosed as suspected subtotal to total occlusion (limited studies), and of these, three were occluded on angiography, eight had stenoses ranging from 90% to 99%, and one had 80% stenosis.

CONCLUSIONS

A carotid duplex ultrasound study is an acceptable method for predicting total carotid occlusion when the study is optimal, and angiography is unnecessary in asymptomatic patients. Angiography is recommended for patients who are surgical candidates with a limited duplex study.

Immune responses to the HLA-A*0201-restricted epitopes of tyrosinase and glycoprotein 100 enable control of melanoma outgrowth in HLA-A*0201-transgenic mice

Many of the Ags recognized by human melanoma-reactive CTL are derived from proteins that are also expressed in melanocytes. The possibility of self-tolerance to these epitopes has led to questions about their utility for antitumor immunotherapy. To investigate the issue, we established a preclinical model based on transgenic mice expressing a recombinant HLA-A*0201 molecule and B16 melanoma transfected to express this molecule. HLA-A*0201-restricted epitopes from the melanocyte differentiation proteins (MDP) tyrosinase and gp100 are expressed in both tumor cells and melanocytes, and the former is associated with self-tolerance. However, adoptive transfer of tyrosinase or gp100-reactive CTL developed from tolerant mice delayed tumor outgrowth, as did immunization with MDP peptide-pulsed dendritic cells. Protection was enhanced by the use of peptide ligands containing conservative substitutions that were cross-reactive with the original Ags. These data establish that CTL populations reactive against MDP-derived self-Ags can be activated to mount effective antitumor immunity and strongly support their continued development for tumor immunotherapy in humans.

A recombinant chimeric plasminogen activator with high affinity for fibrin has increased thrombolytic potency in vitro and in vivo

A recombinant plasminogen activator with high fibrin affinity and specificity was expressed by transfecting hybridoma cells with a plasmid that combines sequence coding for low molecular mass (32 kDa) single-chain urokinase-type plasminogen activator [scuPA(32kDa)] and anti-fibrin monoclonal antibody 59D8. The expression of the recombinant molecule [r-scuPA(32kDa)-59D8] was optimized by replacing the 3' untranslated region (initially that of high molecular mass scuPA) in the plasmid with the 3' untranslated region of either beta-globin or mouse immunoglobulin. This modification resulted in a greater than 100-fold improvement in the level of protein expression. The 103-kDa r-scuPA(32kDa)-59D8 protein displayed catalytic activity indistinguishable from that of high molecular mass scuPA and fibrin binding comparable to that of native antibody 59D8. r-scuPA(32kDa)-59D8 was 6 times more potent than high molecular mass scuPA in lysing a human plasma clot in vitro and was 20 times more potent than high molecular mass scuPA in the rabbit jugular vein model of thrombolysis. Molecules of this type may serve as prototypes for highly specific, antibody-targeted enzymes suitable for human use.

Activation of the NPY Y5 receptor regulates both feeding and energy expenditure

Intracerebroventricular (ICV) administration of neuropeptide Y (NPY) has been shown to decrease energy expenditure, induce hypothermia, and stimulate food intake. Recent evidence has suggested that the Y5 receptor may be a significant mediator of NPY-stimulated feeding. The present study attempts to further characterize the role of NPY Y5-receptor subtypes in feeding and energy expenditure regulation. Satiated Long-Evans rats with temperature transponders implanted in the interscapular brown adipose tissue (BAT) displayed a dose-dependent decrease in BAT temperature and an increase in food intake after ICV infusion of NPY. Similar effects were induced by ICV administration of peptide analogs of NPY that activate the Y5 receptor, but not by analogs that activate Y1, Y2, or Y4 receptors. Furthermore, ICV infusion of the Y5 selective agonist D-[Trp(32)]-NPY significantly reduced oxygen consumption and energy expenditure of rats as measured by indirect calorimetry. These data suggest that the NPY Y5-receptor subtype not only mediates the feeding response of NPY but also contributes to brown fat temperature and energy expenditure regulation.

Toxicity of enzymically-oxidized low-density lipoprotein

Intravenous injection of cholesterol oxidase into hyperlipidemic rabbits in which aortic atheromatous lesions have been induced by dietary means is lethal within hours, whereas injection of the same enzyme into normal rabbits has no visible adverse effect. The lethal effect of the enzyme is explicable by the finding that injection of cholesterol-oxidase treated low-density lipoprotein kills normal rabbits, in contrast to untreated low-density lipoprotein which does not. Enzymically oxidized low-density lipoprotein was also found to be cytotoxic for two human cell lines and for cultured bovine aortic endothelial cells. We suggest that in vivo enzymic conversion of low-density lipoprotein cholesterol to low-density lipoprotein cholestenone may possibly play a role in the initiation of atheromatous lesions in humans.

Hydrolytic properties of phenylalanyl- and N-acetylphenylalanyl adenylate anhydrides

We have used a novel spectrophotometric method to study the hydrolysis of N-acetylphenylalanyl adenylate anhydride (AcPhe-AMP) and phenylalanyl-adenylate anhydride (Phe-AMP) at low concentrations (10(-5) M), 25 degrees C, constant buffer concentration (0.05 M), and as a function of pH. While Phe-AMP is susceptible principally to attack by OH-, with two different rates depending on whether the alpha-amino group of the amino acid is protonated or not, the AcPhe-AMP is susceptible to acid decomposition as well. At pH's 4-8, the Phe-AMP hydrolyzes faster than the AcPhe-AMP, but at pH less than 4 or pH greater than 8, the blocked form hydrolyzes faster. Both forms are also attacked by H2O, and at the same rate. Moreover, the hydrolysis of Phe-AMP is shown to be greatly catalyzed by carbonate, although the AcPhe-AMP is not subject to such catalysis. The rate laws for the various mechanisms and the activation energies for the hydrolyses at pH 7.1 are given.

A2A receptor antagonists do not induce dyskinesias in drug-naive or L-dopa sensitized rats

L-dopa, the precursor to dopamine, is currently the gold standard treatment for Parkinson's disease (PD). However, chronic exposure is associated with L-dopa-induced dyskinesias (LIDs), a serious side effect characterized by involuntary movements. Adenosine A2A receptor antagonists have been studied as a novel non-dopaminergic PD treatment. Because A2A receptor antagonists do not act on dopamine receptors, it has been hypothesized that they will not induce dyskinesias characteristic of L-dopa. To test this hypothesis in a rodent model, the A2A receptor antagonists SCH 412348 (3 mg/kg), vipadenant (10 mg/kg), caffeine (30 mg/kg), or istradefylline (3 mg/kg) were chronically (19-22 days) administered to Sprague Dawley rats, and dyskinetic behaviors were scored across this chronic dosing paradigm. Unlike L-dopa, there was no evidence of dyskinetic activity resulting from any of the four A2A receptor antagonists tested. When delivered to animals previously sensitized with L-dopa (6 mg/kg), SCH 412348, vipadenant, caffeine or istradefylline treatment produced no dyskinesias. When administered in combination with L-dopa (6 mg/kg), SCH 412348 (3 mg/kg) neither exacerbated nor prevented the induction of LIDs over the course of 19 days of treatment. Collectively, our data indicate that A2A receptor antagonists are likely to have a reduced dyskinetic liability relative to L-dopa but do not block dyskinesias when coadministered with L-dopa. Clinical studies are required to fully understand the dyskinesia profiles of A2A receptor antagonists.

Interleukin-12 overcomes paclitaxel-mediated suppression of T-cell proliferation

The antineoplastic agent paclitaxel (TAXOL) is a potent inhibitor of tumor cell division and a useful chemotherapeutic for the treatment of refractory ovarian and breast carcinoma. Multiple immune system actions have been ascribed to paclitaxel, including the capacity to induce macrophage antitumor cytotoxic molecule production. However, T-cells are susceptible to paclitaxel's cytostatic functions, and no studies have investigated the effects of direct paclitaxel administration on lymphocyte function in the tumor-bearing host (TBH). Because paclitaxel is currently used as an antitumor chemotherapeutic agent and tumor growth alters leukocyte functions, we assessed T-cell function following chemotherapeutic-type paclitaxel treatment. Paclitaxel administration significantly compromised the proliferative capacity of both normal host and TBH lymphocytes in vitro. Although tumor growth impaired T-cell interferon-gamma (IFN-gamma) production, paclitaxel treatment did not alter IFN-gamma. We speculate that the immunostimulatory cytokine interleukin-12 (IL-12), which promoted T-cell activation and proliferation, was capable of reversing paclitaxel-mediated immunosuppression. Exogenous IL-12 fully reconstituted proliferative reactivity and enhanced IFN-gamma production by both normal host and TBH lymphocytes in vitro. Collectively, these data suggest that chemotherapeutic paclitaxel regimens impart significant but reversible inhibition of lymphocyte populations, and IL-12 may be a useful ancillary immunotherapeutic to overcome paclitaxel-induced modulation of lymphocyte activities.

A novel method for replacement of the dislodged tracheostomy tube: the nasogastric tube "guidewire" technique

Unscheduled replacement of dislodged tracheostomy tubes can be a challenging procedure for the physician and a frightening event for the patient. Forceful attempts at replacement are both painful and dangerous; such attempts may disrupt the soft tissues adjacent to the tracheostomy tract, creating a false passage and potentiating acute respiratory failure. We describe a technique using a standard nasogastric tube that allows safe and precise replacement of tracheostomy tubes in both sedated and combative patients under routine and emergent conditions.

Congenital cutaneous candidiasis associated with respiratory distress and elevation of liver function tests: a case report and review of the literature

We describe congenital cutaneous candidiasis (CCC) in a term newborn. The mother had candidal vaginitis 1 week before delivery. At birth, the infant had a generalized, intensely erythematous, papulovesicular eruption, respiratory distress and elevation of liver function tests. The child responded well to intravenous amphotericin B plus topical and oral nystatin. There have been 13 previously reported cases of CCC in infants weighing more than 1500 gm who had evidence of systemic infection. Two deaths were attributed to candidal pneumonia and sepsis. The majority of infants with CCC have infection localized to the skin, but if there is any evidence of respiratory distress or signs of sepsis the possibility of systemic candidiasis and the need for parenteral antifungal therapy must be considered.

Fibro-osseous pseudotumor of the digit: a comparison to myositis ossificans by light microscopy and immunohistochemical methods

Fibro-osseous pseudotumor of the digit is an unusual cutaneous process characterized histologically by a fibroblastic proliferation admixed with reactive/metaplastic osteoid formation. The osteoid formation can be florid and immature, mimicking the appearance of malignant osteoid-forming neoplasms. Fibro-osseous pseudotumor of the digit has histologic and clinical features in common with myositis ossificans. This has led many to consider the two to be synonymous. We studied three cases of fibro-osseous pseudotumor, compared to five cases of myositis ossificans, using routine light microscopy and a battery of immunohistochemical stains. Both entities displayed a "zoning" pattern of immature spindled areas admixed with more mature areas having osteoid metaplasia. This was more pronounced in myositis ossificans. In each lesion, the spindle cells stained positively for vimentin and actin. CD34 and Factor VIII highlighted the vasculature. No stromal staining for MAK-6 (cytokeratin) or S-100 was identified. Ki-67, a proliferation marker, showed positive staining of the stromal cells in both lesions, which was strongest in the immature spindled areas. The immunohistochemical and histologic similarities of the lesions support fibro-osseous pseudotumor of the digit being a cutaneous variant of myositis ossificans.

A new technique for transbronchial biopsy in infants and small children

We describe a technique of transbronchial biopsy (TBB) in small children, using a plastic suction catheter as the working channel through which biopsy forceps are introduced. An ultrathin (2.2 mm) flexible fiberoptic bronchoscope (FFB) was used to direct the catheter visually into the desired lung segment and to biopsy selectively. This technique was used nine times to obtain biopsy specimens in six different patients, ranging in age from 3 months to 3 and 4/12 years (mean, 19.2 months). Adequate specimens were obtained in eight of nine procedures (89%). Complications included one pneumothorax that did not require evacuation and one episode of sedation-induced hypoventilation that required brief bag-mask ventilation. No significant bleeding occurred. This technique enabled us to obtain lung tissue in infants and small children without resorting to general anesthesia and rigid bronchoscopy.

Subcutaneous Castleman's disease of the wrist

Castleman's disease usually occurs as a solitary lesion in the mediastinum and less frequently in the neck region. Two variants are recognized, the more common hyaline-vascular type and the plasma cell type. A third hybrid, or intermediate, variant exists that shares features with both the hyaline-vascular and plasma cell types. Uncommonly, these lesions occur outside the mediastinum or neck region. We report a case of subcutaneous Castleman's disease of the intermediate type on the wrist of a 56-year-old woman without systemic symptoms.

Taxol, a microtubule-stabilizing antineoplastic agent, differentially regulates normal and tumor-bearing host macrophage nitric oxide production

Taxol, a potent antitumor chemotherapeutic, promotes in vitro cytotoxic antitumor activities by normal host macrophage (M phi s). Because tumor growth induces functional changes among M phi populations, we determined whether fibrosarcoma growth (Meth-KDE) modified M phi responsiveness to the activating agent taxol. Tumors induce tumor-distal M phi populations to become immune suppressor cells, partially through overproduction of the cytotoxic and proinflammatory molecules nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha). Beneficial to the tumor-bearing host (TBH) when released by tumor-proximal M phi s, NO and TNF-alpha suppress lymphoproliferation and fail to impart antitumor activity when expressed in tumor-distal compartments. We report that taxol differentially regulated normal host and TBH M phi production of the immunosuppressive molecule NO by tumor-distal M phi populations. In response to IFN-gamma-priming and taxol triggering, TBH M phi s increase their production of NO as compared to resting M phi s; however, unlike normal host M phi s, taxol-induced TBH M phi NO production was significantly suboptimal. Modulation of TBH M phi NO production in tumor-distal compartments may alleviate M phi-mediated suppression of T-cell proliferative responses, yet promote sufficient NO production by tumor-associated M phi s to affect cytotoxicity. Collectively, these data leave implications for immunotherapeutic activities by the anticancer drug taxol.

A male genital tract-specific carbohydrate epitope on human CD52: implications for immunocontraception

The identification of unique sperm surface epitopes that are not expressed or exposed in the female reproductive tract is a key element in the development of antibody-based contraceptives. Western blotting and immunohistochemistry were performed to define the tissue distribution of the S19 epitope, which has been proposed as a target for immunocontraception. S19 is an IgG1 murine monoclonal antibody (mAb) directed to an N-linked carbohydrate epitope on a 15-25 kDa glycoprotein, sperm agglutination antigen-1 (SAGA-1), containing a peptide core identical to that of the lymphocytic surface protein CD52. In this study, the S19 epitope was shown to be absent from human lymphocytes, demonstrating a distinction between this epitope and the CAMPATH epitope that is recognized by an antibody against the terminal tripeptide and GPI-anchor of CD52. Further tissue specificity analysis identified the S19 epitope in the epithelium of the human epididymis and vas deferens, as well as on both epididymal and ejaculated spermatozoa. In contrast, the S19 epitope was absent in the five human female reproductive tract and 18 other somatic tissues tested. These results support the use of the S19 epitope as a contraceptive immunogen and the suitability of the S19 mAb as an intravaginal contraceptive. To test the agglutinating activity of the S19 mAb in a formulation designed for vaginal use, S19 mAb were bound to the surface of Novasomes, a multilamellar liposome delivery vehicle. S19-Novasome formulations agglutinated human spermatozoa and were as effective as unbound S19 mAb, demonstrating the feasibility of spermistatic contraceptives targeted to the male reproductive tract specific carbohydrate epitope.

Prenatal diagnosis of fetal disseminated intravascular coagulation associated with umbilical cord arteriovenous malformation

BACKGROUND

Congenital disseminated intravascular coagulation (DIC) has been reported in a variety of clinical settings, but to our knowledge, it has never been documented before birth. We describe prenatal identification of an umbilical cord vascular tumor and echogenic foci in the fetal liver leading to the diagnosis of fetal DIC by funipuncture.

CASE

A large vascular tumor of the umbilical cord was identified using prenatal sonography. At 31 weeks' gestation, echogenic areas, which were thought to represent infarcts or thrombi, were seen in the liver. When funipuncture revealed florid fetal DIC, delivery was accomplished by cesarean to prevent intracranial bleeding. Pathologic examination of the umbilical cord tumor showed it to be a large arteriovenous malformation.

CONCLUSION

Arteriovenous malformations may cause fetal coagulopathy. This case illustrates that funipuncture may be used to diagnose this condition and that timely cesarean delivery may contribute to a favorable outcome.

Complexes of polyadenylic acid and the methyl esters of amino acids

This report includes studies of the binding of the methyl esters of a series of amino acids to polyadenylic acid. The principal data were obtained using proton NMR; however, some additional data were obtained through the study of insoluble complexes and through ultraviolet spectroscopy. The binding constants are in the order Phe greater than Ile greater than or equal to Leu greater than Val greater than Gly, and show a direct correlation with the hydrophobicities of the amino acids. In most cases they are essentially double the binding constants found by Reuben and Polk (1980) for monomeric AMP. All of these amino acids, except Gly, have A as the middle letter of their anticodons, and Phe is the only one with XAA as its only anticodon. It has the anticodon richest in A and has the highest binding constant for A. These results, coupled with other data, continue to support a model of the origin of the code which is based on weak, but selective affinities between amino acids and their anticodons.

Multinucleate cell angiohistiocytoma of the upper lip

Multinucleate cell angiohistiocytoma is a rare benign fibrohistiocytic vascular tumor with distinctive histologic features. It appears clinically as small, slow-growing, grouped reddish-brown to purple papules and nodules that may be mistaken for other vascular proliferative or reactive conditions. Multinucleate cell angiohistiocytoma tends to occur more frequently in women, to favor the extremities, and to appear as multiple lesions. We report a case of solitary multinucleate cell angiohistiocytoma that appeared as a nodule on the upper lip of a man but that otherwise demonstrated characteristic histologic and immunohistochemical features. Greater awareness of this uncommon benign lesion will facilitate diagnosis and appropriate management.

Decline in creatinine clearance in a patient with glomerulomegaly associated with a congenital cyanotic heart disease

Glomerulomegaly is associated with congenital cyanotic heart disease and has heretofore been considered a benign condition. We describe a patient with congenital cyanotic heart disease and glomerulomegaly. Deterioration of renal function was demonstrated by comparison of creatinine clearances measured at the time of kidney biopsy and 4 years later. No alteration in kidney histology other than glomerulomegaly and focal glomerulosclerosis at autopsy could account for this deterioration. This is the first description of deterioration of renal function in a patient with glomerulomegaly and congenital cyanotic heart disease. This observation may influence the management of patients with glomerulomegaly and congenital cyanotic heart disease who are potential recipients of heart or heart-lung allografts.