Antibody-targeted delivery of doxorubicin entrapped in sterically stabilized liposomes can eradicate lung cancer in mice

Cancer chemotherapy is limited by adverse side effects resulting from toxicities to normal tissues. Targeted delivery of drugs to diseased tissues in vivo would help to reduce these side effects. Liposomes containing lipid derivatives of polyethylene glycol have circulation times sufficiently long to allow for effective in vivo drug delivery. Polyethylene glycol liposomes, containing entrapped doxorubicin, targeted to KLN-205 squamous cell carcinoma of the lung by means of specific antibodies attached at the liposome surface were capable of reducing tumor burden to a high degree and eradicating tumor in a significant percentage of mice.

Immunogenicity of synthetic peptides related to the core peptide sequence encoded by the human MUC1 mucin gene: effect of immunization on the growth of murine mammary adenocarcinoma cells transfected with the human MUC1 gene

The immune response of CAF1 mice to various synthetic peptides (SP) related to the amino acid sequence (PDTRPAPGSTAPPAHGVTSA) of the tandem repeat of the MUC1 human breast mucin core peptide was evaluated. The most immunogenic preparations of the synthetic peptides were those conjugated to keyhole limpet hemocyanin (KLH) or clustered in a dendritic multiple antigenic peptide (MAP-4) configuration. The mice were immunized subcutaneously with synthetic peptides emulsified in RIBI adjuvant, employing various immunization protocols. Equivalently high IgG responses were induced using SP-KLH conjugates (GVTSAPDTRPAPGSTA-KLH) or an SP--MAP-4 chimeric configuration (SP1-6), which also included a universal malarial CST-3 T-helper epitope (SP1-6 = SAPDTRPAEKKIAKMEKASSVFNVVNS--MAP-4). These IgG antibodies bound both the appropriate MUC1 synthetic peptides and the cell surface expressed MUC1 mucin on murine mammary cells that had been transfected with the human MUC1 gene and a human breast cancer cell line that expresses cell-surface MUC1. A MAP-4 molecule, which included the entire 20-amino-acid sequence of the MUC1 tandem repeat (SP1-5 = PDTRPAPGSTAPPAHGVTSA-MAP-4) induced a poor IgG response. In contrast, all three types of molecule: SP-KLH, SP1-6 and SP1-5, were found to be good immunogens for the induction of specific delayed-type hypersensitivity (DTH) reactions measured using either synthetic peptides or MUC1-transfected cells. In addition, immunization with irradiated MUC1-transfected cells induced strong DTH reactions measured using synthetic peptides that expressed the PDTRP sequence, which has been shown to be, or to overlap, a T cell epitope in humans and a B cell epitope in mice. Finally, it was demonstrated that synthetic MUC1 peptide "vaccines" could be used both prophylactically and therapeutically to inhibit the growth of MUC1-transfected tumor cells and prolong the survival of tumor-bearing mice.

Immunization of breast cancer patients using a synthetic sialyl-Tn glycoconjugate plus Detox adjuvant

We have synthesized various formulations that have potential for active specific immunotherapy (ASI) of human cancers. Sialyl-Tn (STn) is a potentially important target structure for ASI because its expression on mucins is a strong, independent predictor of poor prognosis, suggesting that it may have functional significance in the metastatic process. In this first pilot study of synthetic sialyl-Tn hapten conjugated to keyhole limpet hemocyanin (STn-KLH), with Detox adjuvant, toxicity and humoral immunogenicity were assessed in 12 patients with metastatic breast cancer. Toxicity was minimal, restricted to local cutaneous reactions (apart from transient nausea and vomiting following single low-dose cyclophosphamide treatment). Using STn-conjugated human serum albumin in a solid-phase enzyme-linked immunosorbent assay, it was shown that all patients developed IgM and IgG specific for the synthetic STn hapten. Following immunization, most patients were shown to develop increased titres of complement-mediated cytotoxic antibodies, partially inhibited by synthetic STn hapten, but not by the related TF hapten. We also detected IgM and IgG antibodies reactive with natural STn determinants expressed on ovine submaxillary mucin, the STn specificity of this reactivity being confirmed by hapten inhibition. Evaluation of clinical efficacy in a small pilot study is difficult. Five patients are alive 12 or more months after entry, and another 4 patients are alive 6 or more months after entry into the study. All 3 patients with known widespread bulky disease progressed despite ASI, 2 having died from widespread cancer. Two patients had partial responses, each lasting 6 months. While several patients had disease stability for 3-10 months, 1 patient with pulmonary metastases remains stable 15 months after entry into the program.

Active immunization of human ovarian cancer patients against a common carcinoma (Thomsen-Friedenreich) determinant using a synthetic carbohydrate antigen

In a phase I study, ten ovarian cancer patients with extensive metastatic disease despite chemotherapy were immunized three to eight times subcutaneously with the synthetic form of the immunodominant disaccharide (beta Gal1----3 alpha GalNAc) of the Thomsen-Friedenreich antigen conjugated to KLH (TF alpha-KLH) plus DETOX adjuvant. Six patients were given a "low" dose of TF alpha-KLH (100 micrograms/injection) and four patients were given a "high" dose (500 micrograms/injection). All patients received a single low-dose cyclophosphamide treatment (200 mg/m2 i.v.) 3 days prior to commencement of the series of immunizations. Immunizations were 2 weeks apart. Little or no toxicity was noted. As expected, all patients (prior to immunization) had naturally occurring IgM antibodies against the synthetic TF alpha hapten. None of the patients had detectable pre-existing IgG or IgA antibodies against synthetic TF alpha hapten. Nine of the ten ovarian cancer patients showed a significant increase in IgM titer above pre-existing levels following immunizations with TF alpha-KLH plus DETOX adjuvant. These same patients also produced IgG anti-TF alpha and eight of these also produced IgA anti-TF alpha, although the IgA responses were weaker. Most of the IgG responses followed the IgM responses by 2-4 weeks. Two patients produced a vigorous IgG response after their first TF alpha-KLH injection, suggesting a recall response. Both direct ELISAs on various solid-phase synthetic carbohydrate antigens and hapten inhibition experiments confirmed the TF alpha hapten specificity of the antibodies. IgM and IgG anti-TF alpha-specific antibodies reacted with natural TF antigen, by ELISA and FACS analysis, although the titers were generally lower than the titers against the immunizing TF alpha hapten. Increased levels of cytotoxic antibodies against TF-expressing tumor cell targets were detected in eight of the ten patients following immunization. One patient who had no detectable cytotoxic antibodies prior to immunization developed increasingly strong cytotoxic antibodies as a function of the number of immunizations. The low antigen dose patients showed as good or better humoral immune responses than the high antigen dose patients. All four high-dose and four of six low-dose patients developed moderate to strong DTH reactions at the vaccination sites. Our results demonstrate that KLH is an acceptable carrier for carbohydrate haptens in humans and that DETOX is an appropriate nontoxic adjuvant for the generation of high-titer specific anti-carbohydrate responses in human cancer patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Postoperative neuromuscular function in pediatric day-care patients

After anesthesia employing nondepolarizing muscle relaxants, 30%-40% of adult patients demonstrate residual paralysis with a train-of-four ratio less than 70%, but it is not known if the same is true for children. This study was designed to investigate neuromuscular transmission in 91 ASA physical status I or II day-care children (aged 0-10 yr) after halothane anesthesia in which pancuronium (n = 34), atracurium (n = 32), or vecuronium (n = 25) was administered. Peripheral nerve stimulation was used clinically to assess neuromuscular blockade during surgery. In the recovery room, the evoked response of the adductor pollicis muscle was measured by train-of-four stimulation of the ulnar nerve. This measurement was made (mean +/- SEM) at 18.0 +/- 1.5, 15.0 +/- 1.3, and 15.0 +/- 1.7 min after pharmacologic antagonism with 0.02 mg/kg atropine and 0.06 mg/kg neostigmine in the pancuronium, atracurium, and vecuronium groups, respectively. There were no differences in the ages of the patients in the three groups at 4.3 +/- 0.4, 4.0 +/- 0.4, and 5.0 +/- 0.5 yr, with 17 children less than 2 yr. Recovery from neuromuscular blockade in all three groups was almost complete. The train-of-four ratio (height of fourth twitch compared with the first) was similar in patients who had received pancuronium (96.7% +/- 0.9%), atracurium (95.5% +/- 0.9%), or vecuronium (96.3% +/- 1.3%). Therefore, postoperative muscle weakness or respiratory impairment is unlikely in pediatric day-care surgical patients more than 2 yr old when these anesthetic techniques are used.

Analysis of human tumor associated Thomsen-Friedenreich antigen

The Thomsen-Friedenrich (TF) antigen is a precursor structure of MN blood group antigens and is also expressed by about 90% of human carcinomas. The immunodominant group of TF antigen [beta-galactosyl(1-3)-alpha-N-acetylglactosamine] is present in cryptic form in normal RBC and is revealed by neuraminidase treatment. A murine monoclonal antibody (Mab 49H.8) developed against neuraminidase treated human RBC was reactive against a variety of human tumors. We have characterized the human tumor associated TF antigen detected by this antibody from a human transitional bladder carcinoma cell line (647V), a human colon adenocarcinoma cell line (LS174T), and a pleural effusion fluid of a breast adenocarcinoma patient (PE 89). A heterologous sandwich radioimmunoassay for TF antigen was developed using Mab 49H.8 as the catcher and 125I-peanut agglutinin as the probe. Detergent extracts of 647V and LS174T cells, media conditioned by culturing these cells, and PE 89 were shown to contain the antigen by this assay. The specificity of the antigen capture by Mab 49H.8 in this assay was demonstrated by its selective inhibition by nitrophenyl-beta-D-galactoside, phenyl-beta-D-galactoside, and a TF hapten. Preliminary studies on TF antigen in serum samples using this assay showed that about 53.7% of the carcinoma samples contained an antigen concentration greater than 200 units/ml whereas for 90.9% of the normal samples the antigen concentration was below 200 units/ml. These studies demonstrated that the TF antigen is shed by the tumor cells both in vitro and in vivo. The TF antigen was sensitive to treatment with alkali (0.1 M NaOH for 5 h at 37 degrees C) and periodate (10 mM sodium periodate for 1 h at room temperature), was resistant to acidic pH (50 mM acetate buffer, pH 4.5, for 5 h at 37 degrees C), and could be extracted with perchloric acid (0.6 M for 1 h at 4 degrees C). The antigen was shown to be a high molecular weight glycoprotein (Mr greater than 1,000,000) by gel filtration chromatography. The density of the antigen was estimated to be about 1.35 g/ml by cesium chloride density gradient centrifugation. The antigen could be isolated from conditioned media by a combination of affinity chromatography and gel filtration with an overall purification of about 61,432-fold and a final recovery of 53.2%.(ABSTRACT TRUNCATED AT 400 WORDS)

Effective drug-antibody targeting using a novel monoclonal antibody against the proliferative compartment of mammalian squamous carcinomas

mAb 174H.64, which selectively recognizes an epitope expressed on the proliferating cells of mammalian squamous carcinomas, was covalently coupled to daunomycin (DM) by an acid-sensitive linker and tested for its selective cytotoxicity for squamous carcinomas. A murine lung squamous carcinoma model for chemoimmunotherapy using mAb 174H.64-DM conjugates was developed. This model utilizes the KLN-205 cell line, which metastasizes to the lungs following i.v. injection and shows a pattern of growth similar to those of spontaneous squamous carcinomas, characterized by highly proliferative cells at the periphery of the tumor (reactive with 174H.64) with the keratinized differentiated cells toward the center (not reactive with 174H.64). 174H.64-DM conjugates showed marked and specific cytotoxicity against KLN-205 cells both in vitro and following i.v. injection of the immunoconjugate in mice with established lung metastases. The conjugate was nearly as effective as daunomycin alone when incubated in vitro with KLN-205 cells and much more effective than daunomycin alone in vivo or other control immunoconjugates, which were ineffective. Finally, while the free 174H.64 mAb produced a significantly increased time of survival of mice bearing KLN-205 metastases, a much greater survival was found with mice treated with the 174H.64-DM immunoconjugate, some mice apparently demonstrating long-term survival (greater than 100 days). We conclude that mAb 174H.64 may have potential therapeutic benefit against squamous carcinoma.

A novel marker for basal (stem) cells of mammalian stratified squamous epithelia and squamous cell carcinomas

We have developed a monoclonal antibody (174H.64) which selectively recognizes antigens shared by the basal cells of mammalian stratified squamous epithelium and squamous cell carcinoma (SCC). Histopathological studies of the frozen tissue sections demonstrated selective binding of this antibody to SCCs of human, bovine, canine, feline, and murine origin. Tumors of other histological types did not show reactivity with the antibody. In well-differentiated SCCs the peripheral layer of the tumor showed preferential binding of the antibody, suggesting that the antigens are associated with the proliferative compartment of the tumor. Studies on normal human tissues showed selective binding of the antibody to the basal layer of stratified squamous epithelia, thymic epithelial cells, and myoepithelial cells around breast ducts, while no antibody binding was observed for the suprabasal layers of stratified epithelia, simple epithelia, or tissues of nonepithelial origin. A similar pattern of antibody binding was also observed for bovine and murine skin with staining of the basal layer. The antigens detected by monoclonal antibody 174H.64 were characterized from cytoskeletal protein extracts of normal human keratinocytes as well as human and bovine SCC tissues by using an immunoblotting technique. The antigens detected in normal human keratinocytes consisted of two major protein bands of approximate molecular weights of 48,000-50,000 and 57,000. In bovine SCC tumor the antigen detected was the Mr 48,000-50,000 band and in the human SCC tumor it was the Mr 57,000 band. A murine lung SCC model was developed with a murine SCC cell line KLN-205. The lung tumor obtained was reactive against the antibody and showed selective staining of the peripheral layer of the tumor containing the stem cell population. The antigens described by monoclonal antibody 174H.64 appear to be molecules associated with the stem cell populations of normal stratified epithelium and squamous cell carcinoma.

Mycotic aneurysm of the petrous portion of the internal carotid artery

A case of a mycotic aneurysm of the petrous portion of the internal carotid artery is presented. This entity is extremely rare and the problems associated with the diagnosis and clinical management are discussed.

Tuning forks: the problem of striking

Tuning fork tests have accompanied us from the beginning of otology. Various methods of striking have been used during the century and the efforts to attain standardization appear to have been forgotten since audiology became available. The article reviews the history of the standardization and throws a new light on the production of overtones and air, compared to bone, conduction frequency. The article stresses the importance of tuning fork testing in clinical practice.

The in vitro evaluation of nucleoside analogues as probes for use in the noninvasive diagnosis of herpes simplex encephalitis

1-(2-Deoxy-2-fluoro-beta-D-arabinofuranosyl)-5-iodouracil (FIAU) and the 5-iodo (FIRU), 5-bromo (FBrRU), 5-chloro (FClRU) and 5-fluoro (FFRU) analogues of 1-(2-deoxy-2-fluoro-beta-D-ribofuranosyl)uracil were examined in four in vitro tests designed to evaluate their potential as radiopharmaceuticals in a non-invasive diagnostic test for herpes simplex encephalitis (HSE). The tests involved, (a) cellular uptake studies--which showed that all five nucleosides are selectively trapped in rabbit kidney cells infected with herpes simplex virus, type I, which codes for its own thymidine kinase; (b) incubation studies--which showed that, in human platelets, FIAU, FIRU and FFRU are not degraded by thymidine phosphorylase (an enzyme which catalyzes the glycosidic bond cleavage of physiological nucleosides); (c) a transport study, using mouse erythrocytes--which indicated that all five nucleosides have good affinity for a NBMPR-sensitive nucleoside transporter, with inhibition constants (Ki values in the range of 0.177-0.41; and (d) determination of octanol/water partition coefficients--which (log P = -0.14 to -1.67) indicated that FIAU is the most lipophilic of the five compounds studied, and may therefore cross the blood-brain barrier most readily. We conclude from the results that FIAU is the most promising compound for further evaluation in HSE animal models. The combination of tests described in this study provide a useful screening protocol for evaluation of other nucleoside analogues of potential use in a diagnostic test for HSE.

Lateral sinus thrombosis (a review of 45 cases)

Forty-five cases of lateral sinus thrombosis were recorded in King Edward VIII Hospital from 1978 to 1984. Eighty-two per cent of the patients were under the age of 15 years. Associated complications recorded were: 9 patients with meningitis, 4 with posterior-fossa abscess, 1 patient suffering from posterior fossa empyema; 4 presented with facial palsy and 1 with tuberculous mastoiditis. Four deaths were recorded. Findings at mastoidectomy showed a prevalence of infective granulations (60 per cent) over cholesteatoma (40 per cent) as a cause of the extension of infection. The surgical protocol for the management of lateral sinus thrombosis was mastoidectomy, needling the sinus and removal of the thrombus, if necessary. Medical treatment consisted of Ampicillin and Metronidozol.

Effect of acyclovir on the uptake of 131I-labelled 1-(2'fluoro-2'-deoxy-beta-D-arabinofuranosyl)-5-iodouracil in herpes infected cells

Selective uptake of nucleoside analogues by herpes simplex virus infected cells may serve as the basis for a specific non-invasive diagnostic test for herpes simplex encephalitis. We have examined the effect of acyclovir on the selective uptake of [131I] 1-(2'-fluoro-2'-deoxy-beta-D-arabinofuranosyl)-5-iodouracil in herpes simplex virus infected primary rabbit kidney cells. Infected cells treated with acyclovir continued to concentrate [131I] 1-(2'-fluoro-2'-deoxy-beta-D-arabinofuranosyl)-5-iodouracil for up to 24 h after the addition of the antiviral agent. These results indicated that therapy with acyclovir for as long as 24 h would not prevent the selective trapping of nucleoside analogues. This has important implications for the use of nucleoside analogues in diagnostic brain scans to detect herpes simplex encephalitis.

Nerve/muscle pedicle graft for bilateral vocal cord palsy

The nerve-muscle pedicle graft was successfully used in six of the seven patients admitted with bilateral vocal cord palsy. The diagnostic evaluation included bilateral vocal cord palsy for more than six months; passive mobility test of the arytenoids under general anaesthesia; and exclusion of an organic lesion as a cause of the vocal cord paralysis. The post-operative assessment was done by indirect or direct laryngoscopy. An improvement in phonation and respiration was noted 4 to 10 weeks after the operation. An exertional test was performed. Identification of the origin of ansa cervicalis from the hypoglossal nerve facilitated the operation.

Use of Xe-133 gas in the detection of foreign bodies in the lower respiratory tract

Six patients with a clinical picture of inhaled foreign body and normal chest radiograph were selected for a study with Xenon 133 screening of the lung. The scan was positive in 3 cases from whom a foreign body was removed. The remaining 3 cases in whom the scan was negative were discharged and an uneventful follow-up was recorded. Xenon 133 scanning was found to be useful in the selection of patients for bronchoscopy.

Oncocytic cyst of the larynx. A case report

Cystic oncocytoma of the larynx is rare, and found mainly in older patients; there is a female preponderance. It arises mainly from the ventricle. These lesions are considered to be metaplastic or hyperplastic rather than neoplastic. Regardless of the pathogenesis, complete excision is associated with a good prognosis. A case is reported.

Tuberculous mastoiditis

Twenty-three cases of tuberculous mastoiditis are presented, nine of which were complicated by facial palsy. Six presented with acute mastoiditis, and two had meningitis. Surgery was required in 16 patients; in four cases the diagnosis was made by culture and in another four by biopsy of the granulations or polyp of the external canal. The response to antituberculous treatment was satisfactory in 22 cases. One patient, whose case was complicated by meningitis, died.

Intracranial otogenic complications: a persisting problem

Three hundred thirty-five cases of acute mastoiditis with complications due to extension of infection beyond the mastoid are reported. Two hundred twenty-four of those presented with intracranial sepsis. Meningitis occurred in 83 cases, brain abscess in 53, extradural abscess in 49 cases, and lateral sinus thrombosis in 39 cases. Intracranial complications are frequently seen in this group of patients with neglected otitis media. The complications occurred frequently in children and young adults (74%) with an overall mortality rate of 14%. Meningitis was the most common complication (37%); brain abscess had the highest mortality rate (36%). The overall mortality rate from intracranial complications was reduced in comparison with previous reported series. This is attributed to antibiotic treatment, the use of CT scan in excluding other intracranial complications, and close cooperation between the otologist and neurosurgeon.

Pharmacokinetics and metabolism of E-5-(2-[131I]iodovinyl)-2'-deoxyuridine in dogs

E-5-(2-Iodovinyl)-2'-deoxyuridine (IVdU) is a potent inhibitor of herpes simplex virus type 1 replication in vitro. The selective antiviral activity of IVdU is due to preferential phosphorylation by the herpes simplex virus type 1-encoded thymidine kinase. This selective sequesteration provided the rationale for the development of radioiodinated IVdU as a potential radiopharmaceutical compound for use in noninvasive diagnosis of herpes simplex virus encephalitis. We studied the pharmacokinetics and the in vivo metabolism of [131I]IVdU in dogs. The radioactive components in plasma were characterized and quantitated by radio high-pressure liquid chromatography. During incubation with dog blood, [131I]IVdU was metabolized to the corresponding base (E)-5-(2-iodovinyl)uracil. 131I-labeled (E)-5-(2-iodovinyl)uracil accounted for 73% of the total radioactivity present in plasma after 2 h of incubation, suggesting that phosphorolysis of the nucleoside is the major degradation pathway of IVdU in blood. The in vivo studies showed that there was an initial rapid clearance of the tracer from blood, followed by a second very slow clearance phase. Evaluation of the renal excretion of the radiotracer showed that only 8% of the injected dose was excreted by kidneys over an 8-h period. IVdU was rapidly metabolized to three radioactive compounds. Two of these metabolites, the base (E)-5-(2-iodovinyl)uracil and iodide, were characterized. The radioactivity associated with these metabolites was responsible for the slow clearance phase. Our results suggest that the development of [131I]IVdU as a radiopharmaceutical compound will require measures to prevent its rapid degradation in vivo.

The use of piracetam in vertigo

A pilot study with piracetam (Nootropil; UCB) was performed in 5 selected dizzy patients who had a diagnosis of presbyvertigo or vertebrobasilar insufficiency. The study was monitored by assessing the effect of piracetam on the pursuit-tracking system. All patients showed a remarkable improvement in their pursuit tracking, in addition to marked subjective improvement in their vertigo.

Otogenic complications with an intact tympanic membrane

A review of 21 cases of complications of acute otitis media with a hyperemic, dull, bulging but intact tympanic membrane is presented. All cases had a retroauricular swelling. In 10 cases, a subperiosteal abscess was found, 1 of them complicated with a posterior fossa abscess, 2 had meningitis, 3 had Bezhold's abscess, 2 had thrombosis of the lateral sinus, 1 had a cerebellar abscess, 1 had cerebellitis, and 2 presented with facial nerve palsy. Ninety percent of the patients were below the age of 13. An incomplete course of antibiotic treatment was found to have been given in seven cases (30%) prior to admission. Surgical therapy consisted of a cortical mastoidectomy and a wide myringotomy. Ventilating tubes were inserted in three patients. The mastoid radiography demonstrated cloudiness, and CT scan was performed in six patients with suspected intracranial complications. The present study stresses that an intact tympanic membrane with minimal changes may be regarded by the medical profession with a low index of suspicion and can lead to severe otogenic complications. The disease can be masked by an improper antibiotic therapy.

Hamartomas of the head and neck. A report of 4 cases

Hamartomas in the head and neck region are unusual, and few reports of such lesions are found in the literature. Four cases of hamartoma are described. Two were lymphoid hamartomas (1 occurred in the neck and 1 in the parotid gland), the third was a vascular hamartoma of the ethmoid, and the fourth was found in the neck and was composed of cartilage and fibrofatty tissue.

Surgery for correction of bilateral choanal atresia

A transnasal approach was employed in 28 neonates (26 blacks and 2 whites) with bilateral choanal atresia. In each patient the atresia was perforated microsurgically with the drill, followed by insertion of a Portex endotracheal tube for a period of three months. By this method a satisfactory nasal respiration was established immediately. Removal of the posterior part of the vomer is crucial to the successful result. During the follow-up, one death was recorded in a microcephalic neonate, unrelated to the operation and another four patients required repositioning of the tube under general anesthesia. We feel that the above technique is simple and definitive with negligible complications.

Effects of desipramine on stimulation-induced contractions of the vas deferens of rats pretreated either chronically with desipramine or acutely with idazoxan

In the present studies the effects of desipramine on the functional sensitivity of the prejunctional alpha 2-adrenoceptors of the vas deferens were studied in pithed rats; contractions of the tissue were evoked by electrical stimulation (6 Hz) of the spinal sympathetic outflow. Twenty-four hours after a single dose of desipramine (10 mg/kg, intraperitoneally) the inhibitory dose-response curves to either UK 14 304 or desipramine itself did not differ significantly from those seen in control animals, whereas both were displaced significantly to the right after 15 days pretreatment with desipramine. Thus the functional responsiveness of the prejunctional alpha 2-adrenoceptors of the vas deferens was reduced by chronic but not acute pretreatment with desipramine. In acute studies desipramine (0.3-4.3 mg/kg, intravenously) inhibited electrically induced contractions of the vas deferens of pithed rats. In the presence of the selective alpha 2-adrenoceptor antagonist idazoxan (1 mg/kg, intravenously) desipramine potentiated nerve stimulation. Although idazoxan (10-1440 micrograms/kg, intravenously) itself potentiated electrically induced contractions of the vas deferens the potentiation observed was markedly less than that obtained in rats pretreated acutely with desipramine (0.3 mg/kg, intravenously). Acute simultaneous blockade of both prejunctional alpha 2-adrenoceptors and uptake into nerve terminals can produce maximal potentiation of the contraction of the vas deferens to sympathetic nerve stimulation. Results are discussed in relation to the hypothesis that the combination of an uptake inhibitor and a prejunctional alpha 2-adrenoceptor antagonist, by enhancing noradrenergic transmission, may provide an antidepressant therapy with rapid onset of action.

Synthesis of 131I, 125I and 82Br labelled (E)-5-(2-halovinyl)-2'-deoxyuridines

Radiohalogenated (E)-5-(2-iodovinyl)-2'-deoxyuridine (IVDU, 4) and (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU, 5) were synthesized by reaction of (E)-5-(2-carboxyvinyl)-2'-deoxyuridine (1) with radiolabelled iodide or bromide in the presence of chloramine-T. A "no-carrier-added" synthesis of [131I]IVDU was completed within 30 min providing a radiochemical yield of 65%. Alternatively, radioactive iodine was incorporated into IVDU using a halogen isotope exchange reaction catalyzed by cuprous ion. [82Br]BVDU was also prepared by direct neutron activation of unlabelled BVDU.

Quantitative uptake studies of 131I-labeled (E)-5-(2-iodovinyl)-2'-deoxyuridine in herpes simplex virus-infected cells in vitro

We have synthesized a 131I-radiolabeled antiviral compound (E)-5-(2-iodovinyl)-2'-deoxyuridine (IVdU) and shown that this agent was selectively trapped within rabbit kidney cells, infected in vitro by thymidine kinase-positive (TK+) herpes simplex virus (HSV). The uptake of 131I-labeled IVdU was specific, as it was not concentrated within either HSV (TK-) or mock-infected cells. In certain conditions, over 40% of the radiolabel was selectively trapped within HSV (TK+)-infected cells. This was a 20- to 30-fold increase over the uptake of 131I-labeled IVdU by HSV (TK-) or mock-infected cells. The uptake of 131I-labeled IVdU varied directly with (i) the dose of the virus used to infect the rabbit kidney cells; (ii) the concentration of radiolabeled IVdU added to the system; and (iii) the time of exposure of IVdU to infected cells. The ability of this agent to be trapped within HSV (TK+)-infected cells merits further evaluation in animal models as it has potential as a noninvasive, herpes-specific diagnostic test, in particular for HSV encephalitis.

Asking only one question in the conservation experiment

Rose and Blank have shown that 6-yr-old children do a great deal better in a conservation of number task if they are only asked to make a comparison after the transformation rather than both before and after seeing the quantity transformed. Our experiment shows that this important result applies as well to other materials (mass and volume) and to a wide age range (5-8 yr).

Sleep apnea following bilateral excision of carotid body tumors

A patient is described who developed apnea, hypertention, and tachycardia following the excision of bilateral carotid body tumors. Hypertension and tachycardia resulted, most probably, from bilateral ablation of the carotid sinus and/or the nerve of Hering. These phenomena have been described in the literature. The pathogenesis of the apneic attacks may be related to the ablation of the peripheral sensory organs (both carotid bodies), interference with the function of the respiratory automatic control system, and impaired control of ventilation during non-REM sleep. Temporary unilateral paralysis of the hypoglossal nerve with partial airway obstruction possibly represented a mechanical trigger. The apneic attacks subsided but bouts of hypertention and tachycardia persist.

Cardiac thrombosis and thromboembolism in chronic Chagas' heart disease

A retrospective study of Chagas' heart disease was carried out by a review of 1,345 autopsy reports, with special reference to cardiac thrombus and thromboembolic phenomena. The incidence of cardiac thrombus was higher in cases of heart failure (36%) than in cases of sudden death (15%), higher in heavier hearts, and unrelated to age or sex. The left- and right-sided cardiac chambers were equally affected by thrombus. Endocarditis and blood stasis were considered important factors in the pathogenesis of cardiac thrombus. Thromboembolic phenomena were more common in the systemic circulation but caused relatively more deaths by pulmonary embolism. Fourteen percent of patients with thromboembolic phenomena died from them. Patients with multiple thromboembolic phenomena had a higher risk of death from embolism. Cardiac thrombosis or thromboembolic phenomena, or both, were present in 44% of the cases studied. Prophylactic measures should be taken for these important complications of Chagas' heart disease.

Amyloidosis of Waldeyer's ring. A clinical and ultrastructural report

Amyloidosis of the tonsil is a rare condition and amyloidosis of Waldeyer's ring has not been previously reported. The present study describes a case of amyloidosis of the tonsil, nasopharynx and base of tongue in a 35-year-old patient in otherwise good health and without clinical symptoms. The possibility of systemic amyloidosis was excluded by clinical examination and biopsy of rectal and buccal mucosae. Electron microscopy showed the presence of typical amyloid fibrils. Large masses of the fibrils were closely surrounded by cells which appeared to be phagocytic. The ultrastructure of these cells is described. This case is considered to be a unique type of organlimited amyloidosis of Waldeyer's ring.

Use of middle ear ventilation tubes in recurrent acute otitis media

A method of treatment of recurrent acute otitis media with polythene middle ear ventilation tubes in young children is presented. 56 ears in which infection had persisted for one to six months despite antibiotic therapy and multiple myringotomies were included in the study. The tubes were inserted under topical anaesthesia and cure within one week was obtained in 73 per cent of ears. In another 9 per cent the otorrhoea stopped within 3 weeks, but in 18 per cent reinsertion of the tube became necessary and in this latter group 11 per cent resolved in two weeks following adenoidectomy as well. In 7 per cent the problem remained unresolved. Therefore with this regimen a total of 93 per cent of recurrent infections settled. It is emphasized that the ventilation tube should remain 'in situ' for over 3 months.

Spinal cord compression caused by a metastatic lesion from an aortic body tumour

An aortic body tumour in a 7-year-old wire-haired fox terrier with hind limb ataxia is described. A metastatic lesion in the dorsal arch of the eighth thoracic vertebra caused compression of the spinal cord. Radiographic techniques are discussed that enabled the position and extent of the primary tumour and its metastasis to be defined and allowed a provisional diagnosis of chemodectoma.