A receptor for the immunosuppressant FK506 is a cis-trans peptidyl-prolyl isomerase

The structurally novel macrolide FK506 (refs 1,2) has recently been demonstrated to have potent immunosuppressive activity at concentrations several hundredfold lower than cyclosporin A (CsA). Cyclosporin A, a cyclic peptide, has found widespread clinical use in the prevention of graft rejection following bone marrow and organ transplantation. The mechanisms of immunosuppression mediated by FK506 and CsA appear to be remarkably similar, suggesting that these unrelated structures act on a common receptor or on similar molecular targets, perhaps the CsA receptor, cyclophilin, which has recently been shown by Fischer et al. and Takahashi et al. to have cis-trans peptidyl-prolyl isomerase activity. We have prepared an FK506 affinity matrix and purified a binding protein for FK506 from bovine thymus and from human spleen. This FK506-binding protein (FKBP) has a relative molecular mass (Mr) of approximately 14,000(14K), a pI of 8.8-8.9, and does not cross-react with antisera against cyclophilin. The first 40 N-terminal residues of the bovine and 16 residues of the human FKBP were determined; the 16-residue fragments are identical to each other and unrelated to any known sequences. This protein catalyses the cis-trans isomerization of the proline amide in a tetrapeptide substrate and FK506 inhibits the action of this new isomerase. The FKBP and cyclophilin appear to be members of an emerging class of novel proteins that regulate T cell activation and other metabolic processes, perhaps by the recognition (and possibly the isomerization) of proline-containing epitopes in target proteins.

Synthesis, topoisomerase I inhibitory activity, and in vivo evaluation of 11-azacamptothecin analogs

A series of analogs based on a novel template, 11-aza-(20S)-camptothecin, were obtained from total synthesis and tested as potential anticancer drugs in the topoisomerase I enzyme cleavable complex assay. The parent compound 11-aza-(20S)-camptothecin (8) was derived from a Friedlander condensation between the known aminopyridine derivative 3-(3-amino-4-picolylidene)-p-toluidine and optically active tricyclic ketone 7. Compound 8 had activity approximately twice that of (20S)-camptothecin in the calf thymus topoisomerase I cleavable complex assay. Compounds were prepared wherein the 11-aza nitrogen atom was quaternized as either the corresponding N-oxide or methyl iodide. Compounds with quaternized N-11 showed improved water solubility and were equipotent to the clinically investigated camptothecin analog topotecan in the cleavable complex assay. These compounds were evaluated in vivo in nude mice bearing HT-29 human colon carcinoma xenografts. The analog 11-aza-(20S)-camptothecin 11-N-oxide was found to significantly retard tumor growth when compared to untreated controls. Finally, 7,10-disubstituted 11-azacamptothecin analogs were synthesized using Pd(0) coupling reactions of 10-bromo-7-alkyl-11-aza-(20S)-camptothecins 19 and 20, which in turn were available from a Friedlander condensation of the novel bromopyridine derivatives 17a and 17b with 7. Among the 10-substituted series, a number of analogs displayed extremely high in vitro potency against topoisomerase I and improved aqueous solubility. A significant number of the compounds were found to be active in whole cell cytotoxicity assays and several were evaluated in nude mice bearing the HT-29 tumor xenografts. The most effective of these proved to be (S)-11-aza-7-ethyl-10-(aminohydroximinomethyl)camptothecin trifluoracetic acid salt (27), a potent topoisomerase I inhibitor which demonstrated excellent efficacy in both short term and in extended in vivo assays. A comparison between in vitro enzyme data and in vivo data from nude mouse studies in other compounds in this series revealed a poor overall correlation between topoisomerase inhibition in vitro and antitumor efficacy in vivo.

Renal transplantation using ileal conduits in 5 cases

We report our experience with 5 cases of renal transplantation into ileal conduits and review the literature. In 2 cases a modified surgical procedure was used, which combines a groin extraperitoneal approach for the vascular portion of the operation and a peritoneal window for the anastomosis between the urinary collecting system and the ileal loop. Of our 5 patients 3 are alive with functioning grafts, 1 has undergone retransplantation and 1 with a functioning kidney died of sepsis originating in a decubitus ulcer. Two patients had conduit-related complications. In our literature review of 16 reports 52 per cent of 68 patients were alive with functioning grafts and 32 per cent had conduit-related complications, usually involving urosepsis, calculous disease or stenosis. With a high index of suspicion, and an aggressive diagnostic and therapeutic approach to these problems, a good prognosis can be expected when transplantation is performed in these patients.

Long-term clean intermittent self-catheterization in renal transplant recipients

Eight renal transplant recipients with neurogenic bladders or lower urinary tract dysfunction were managed with clean intermittent self-catheterization after transplantation instead of urinary diversion. A total of 85 treatment months was reviewed. Of the patients 5 continue to do well after 10 to 17 months of intermittent catheterization and 3 suffered immunological graft failures. In selected renal transplant recipients with lower urinary tract dysfunction clean intermittent catheterization is a reasonable alternative to urinary diversion.

Cryptorchidism in the Prader-Willi syndrome

Among 30 male children seen for the Praer-Willi syndrome 21 had at least 1 undescended testis (70 per cent). In 14 of the 30 patients both testes were undescended (45 per cent). Of 18 patients observed for a period 4 (22 per cent) had late spontaneous descent of 6 testes. Gonadotropin treatment facilitated descent in 3 of 4 patients. Testicular biopsy showed a Sertoli-cell-only appearance in 4 patients. The usual indications for orchiopexy of undescended testes may need to be modified in patients with the Prader-Willi syndrome.

Two general routes to 1,4-disubstituted-2,3,4,5-tetrahydro- 1H-3-benzazepines

[structure] Two general routes to 1,4-disubstituted-2,3,4, 5-tetrahydro-1H-3-benzazepines are described. Both routes utilize an appropriately functionalized phenethylamino alcohol as the penultimate intermediate: the first route makes use of the reductive amination of a benzyl alkyl ketone with alpha-(aminomethyl)benzyl alcohol, while the second route utilizes the addition of a Grignard reagent to the oxazolidine derived from a substitued phenylacetaldehyde and alpha-(methylaminomethyl)benzyl alcohol. In all cases studied, the cis-1,4-disubstituted-2,3,4, 5-tetrahydro-1H-3-benzazepine was obtained as the major product.

Urinary tract malformations in identical twins

We describe 3 sets of twins with discordance for urological malformations. Zygosity was documented by HLA and blood group typing. It is suggested that evaluation of the identical twin of an affected patient should include the entire urinary tract because of the potential for different lesions.

Aniridia and Wilms' tumor in a child constitutionally mosaic for 11p-;12q+: a new chromosomal change also present in Wilms' tumor cells of the blastema type

A child with congenital aniridia was assessed closely, by repeated abdominal ultrasound examinations, beginning at birth. The Wilms' tumor subsequently discovered and removed was analyzed karyotypically and found to have some cells with a terminal deletion of chromosome 11; in other cells this deletion was associated with a duplication in the long arm of chromosome 12. These findings were identical to those observed in the patient's peripheral blood mononuclear cells. This case further substantiates the association between changes in chromosome 11 and Wilms' tumor and demonstrates how chromosomal abnormalities in early infancy may lead to the development of Wilms' tumor.

Unsterile intermittent catheterization for meningomyelocele

Twenty-five children with meningomyelocele have been managed by clean unsterile intermittent catheterization (UIC). There were 17 satisfactory results, three total failures, and three partial failures under this regimen. Experience, problems, and causes of failure are discussed. UIC offers a definitive form of management for some types of neurogenic bladder.

Prediction of renal allograft rejection by direct lymphocyte blastogenesis assay

In an effort to better predict renal allograft rejection, lymphocyte blastogenesis (DLBA) was determined in 65 patients after transplants. Of 47 clinically diagnosed rejection episodes 45 had an associated DLBA peak which preceded the clinical diagnosis by an average of 4 days; 11 recipients had DLBA peaks not associated with rejection episodes. Of 14 recipients with multiple DLBA peaks during postoperative periods of nonfunction, none did well. The blastogenesis assay was not a reliable enough predictor of graft rejection to be used as an indication for early elevation of corticosteroid dosage.

In vivo antitumor activity of two new seven-substituted water-soluble camptothecin analogues

The development of camptothecin-like compounds as inhibitors of topoisomerase I for the treatment of resistant tumors has generated clinical excitement in this new class of drugs. We have developed two novel water-soluble camptothecin analogues which are specific inhibitors of topoisomerase I and are potent cytotoxins with significant antitumor activity. We added water-solubilizing groups off position 7 in the B ring of either 10,11-ethylenedioxy- or 10,11-methylenedioxy-20(S)-camptothecin. These water-soluble camptothecin analogues were demonstrated to be nanamolar inhibitors of the topoisomerase I enzyme in the cleavable complex assay. The compounds, GI147211 [7-(4-methylpiperazinomethylene)-10,11-ethylenedioxy-20(S)-camp tot hecin], and GI149893 [7-(4-methylpiperazinomethylene)-10,11-methylenedioxy-20(S)-cam pto thecin], were compared to topotecan, a known water-soluble inhibitor of topoisomerase I. Both GI compounds were found to be slightly more potent than topotecan as inhibitors of topoisomerase I in the cleavable complex assay and were 1.5-2 times more soluble. Tumor cell cytotoxicity assays using 5 separate cell lines demonstrated that both GI compounds were 5-10 times more potent than topotecan, although by comparison all three topoisomerase I inhibitors were unaffected by the multidrug resistance P-glycoprotein. The antitumor activity of all three topoisomerase I inhibitors was compared concomitantly in two human colon xenograft models. In both models, GI147211 and GI149893 were able to induce regression of established HT-29 and SW-48 colon tumors by as much as 60%. The antitumor activity of both compounds were also demonstrated in the MX-1 and PC-3 xenografts. Microscopic examination of selected tissues indicated that drug-induced toxicity was primarily limited to the gastrointestinal tract and was comparable among the three compounds. Further clinical development of this class of compounds is ongoing.

Detection of urinary tract infections in 3- to 5-year-old girls by mothers using a nitrite indicator strip

A program to detect urinary tract infections among 3- to 5-year-old girls was conducted in Madison-Dane County, Wisconsin using local pharmacies as the distribution site for test kits. Screening was conducted at home by mothers with a nitrite dip-strip on three consecutive first morning specimens. Twenty-one percent of the target population participated during a one-month study period. Eighteen cases were found among 1,573 participants (1.1%). In addition, 243 girls other than those in the target area or age group participated and yielded eight additional cases, for a total of 26 cases among 1,816 total participants. The rate of false-positive nitrite tests was 0.3%. Newspapers were the most effective means of alerting the public to the program. The only factors which were associated with less awareness or participation were low socioeconomic and rural residence. Past history of infection, minor urinary symptoms, and pyuria were common among the bacteriuric girls. Immunoglobulin-coated bacteria suggestive of tissue invasion were present in one third of the cases. Vesico-ureteral reflux was present in five and caliectasis in two of 23 girls studied. Despite the likelihood that some bacteriuric girls, particularly those infected with gram-positive organisms were not detected, screening at home appears to be a highly efficient method of detecting urinary tract infections in large populations of preschool children.