The rat testis produces large amounts of an interleukin-1-like factor

Homogenates of whole testis, isolated seminiferous tubules, testicular cytosol, conditioned media from seminiferous tubules obtained from intact or cryptorchid rats, as well as seminiferous tubules devoid of peritubular cells, showed high concentrations of interleukin-1 (IL-1). Cytosol from spleen showed low IL-1 activity, while no activity was found in cytosol from heart, kidney, prostate, ovary or liver. Interleukin-1 activity was not detected in spent medium from cultures of immature Sertoli cells (10-day-old rats) or from peritubular cells or in homogenates of interstitial cells from adult rats. Ultrogel AcA 44 gel chromatography and HPLC size exclusion chromatography exhibited a single peak of IL-1 activity corresponding to a relative molecular mass of 17,000-20,000 (Mr = 17-20 K). Similarly, chromatofocusing revealed only one peak of activity with an apparent isoelectric point of 5-6. It is concluded that the rat testis contains large amounts of an IL-1 alpha-like factor. The adult Sertoli cell or possibly germ cells are suggested as its primary source. Testicular IL-1-like activity is of particular interest in view of the intense cell proliferation during spermatogenesis, and the tendency to testicular relapse of acute lymphoblastic leukaemia.

The use of the myouterine flap in closure of defects of the bladder

A new surgical technique to close bladder defects using well vascularized myouterine flap is described. The flap serves as a temporary scaffold while the bladder is being bridged by natural bladder regeneration. The advantage of this flap is that it is not a free flap, being well vascularized through its pedicle, enhancing optimal bladder regeneration. This technique may be a useful surgical alternative for repair of large bladder defects.

Molecular composition of luteinizing hormone and follicle-stimulating hormone in commercial gonadotropin preparations

The biologic (B) and immunologic (I) properties of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were studied in three commercial urinary gonadotropin preparations and in the first international standard preparation of human urinary gonadotropins before and after fractionation by isoelectrofocusing (IEF). Significant differences were found in the IEF profiles of both bioactive and immunoreactive LH and FSH and in the B/I ratios of the preparations studied. The observed differences in the molecular composition of LH and FSH seem to be attributable to the purification procedures employed. The possible influence of these differences on the in vivo potencies, circulating half-lives, and clinical effects of gonadotropin preparations are discussed.

An unusual adenine phosphoribosyltransferase pseudogene is syntenic with its functional gene and is flanked by highly polymorphic DNAs

A mouse adenine phosphoribosyltransferase (aprt) pseudogene that had previously been recovered from a BALB/c sperm DNA library possessed several unusual features. Its nucleotide sequence, like that of other processed pseudogenes, was colinear with its corresponding mRNA, but it was truncated at its 3' end and lacked a poly(A) tail. The pseudogene was 82% homologous with corresponding regions of the functional gene and had incurred mutations that included transitions, transversions, deletions, and a point insertion. Even though the pseudogene was truncated within the protein-coding region of the corresponding functional gene, it was flanked at both ends by 13-base-pair direct repeats. Curiously, the direct repeats exhibited homology to APRT mRNA at the site of pseudogene divergence. The pseudogene appeared to be common to BALB/c and A/J mice, but it was contained on a 3-kilobase EcoRI fragment in the former strain and a 4.5-kilobase EcoRI fragment in the latter. The BALB/c and apparently the A/J pseudogene both mapped to chromosome 8, which also contains the functional aprt gene. The DNA sequences immediately surrounding the pseudogene in the two strains appeared to be similar, suggesting that the BALB/c and A/J pseudogenes are allelic. However, DNA sequences more distal to the pseudogene in the two strains appeared to vary. Thus, the EcoRI polymorphism was not due to simple loss of an EcoRI site, but was more complex. The pattern of flanking restriction sites was different for each of several enzymes, consistent with extensive DNA rearrangement. Double digests of BALB/c and A/J genomic DNAs revealed complex polymorphisms on both sides of the pseudogene. The results were consistent with insertion, deletion, or other rearrangement of DNA sequences that flank the pseudogene and suggest that this region of mouse chromosome 8 may be a region active for mutation or recombination.

Immunochemical localization and amino acid sequences of crossreactive epitopes within the group A streptococcal M6 protein

mAbs 10A11, 10B6, and 10F5, raised against the native group A streptococcal M6 protein, were examined for their crossreactivity with non-laboratory passaged clinical isolates, representing 58 M serotypes, by bacterial dot blot immunoassay. mAb 10A11 crossreacted with 9, mAb 10B6 with 30, and mAb 10F5 with 30 different non-M6 serotypes. To identify the epitopes for these antibodies, the native M6 protein was cleaved with pepsin or staphylococcal V8 protease. Resultant peptides were purified by HPLC, examined for binding to crossreactive mAbs in ELISA, and reactive peptides were subjected to amino acid sequence analysis. Peptides were aligned with the amino acid sequence of the entire M6 protein predicted by the DNA sequence of the M6 gene. Competitive inhibition studies using peptides synthesized on the basis of peptide and DNA sequences, in concert with selective blocking of amino acid residues, allowed for the further identification and placement of these crossreactive epitopes within the M6 molecule. The 10A11 epitope was located within the six amino acid residues at position 134-139, which repeat at positions 159-164 and 184-189 within the variable amino terminal half of the native molecule. The conserved 10B6 and 10F5 epitopes were positioned within a 15-amino-acid span at position 275-289, with the possibility that either epitope could have been repeated at residues 239-247. Chemical modification of amino acids within this sequence aided in the differentiation of these two epitopes. Such studies should aid in the recognition of a sequence(s) common to a greater number of M serotypes, which may be useful for future vaccine development or group A streptococcal identification.

Static and initiator protein-enhanced bending of DNA at a replication origin

DNA bending has been suggested to play a role in the regulation of gene expression, initiation of DNA replication, DNA packaging, and the recognition of specific DNA sequences by proteins. It has recently been demonstrated that DNA bending can be sequence-directed. Bent DNA has also been observed as a consequence of sequence-specific binding of proteins to DNA. In this report DNA of plasmid pT181 is shown to contain a bend at the replication origin. Furthermore, this bend is enhanced by the binding of the pT181 replication initiator protein, RepC, to the origin.

Peptide models of protein metastable binding sites: competitive kinetics of isomerization and hydrolysis

alpha 2-Macroglobulin and the complement components C3 and C4 each contain a metastable binding site that is essential for covalent attachment. Two cyclic peptides are useful models of these unusual protein sites. Five-membered lactam 1 (CH3CO-Gly-Cys-Gly-Glu-Glp-Asn-NH2) contains an internal residue of pyroglutamic acid (Glp). Fifteen-membered thiolactone 2 (CH3CO-Gly-Cys-Gly-Glu-Glu-Asn-NH2 15-thiolactone) contains a thiol ester bond between Cys-2 and Glu-5. These isomeric hexapeptides are spontaneously interconverted in water. Competing with the two isomerization reactions are three reactions involving hydrolysis of 1 and 2. These five processes were found to occur simultaneously under physiologic conditions (phosphate-buffered saline, pH 7.3, 37 degrees C). Best estimates of the five rate constants for these apparent first-order reactions were obtained by comparing the observed molar percentages of peptides 1-4 with those calculated from a set of exponential equations. Both isomerization reactions (ring expansion of 1 to 2, k1 = 6.4 X 10(-5) s-1; ring contraction of 2 to 1, k-1 = 69 X 10(-5) s-1) proceeded faster than any of the hydrolysis reactions: alpha-cleavage of 1 with fragmentation to form dipeptide 3 (k2 = 3.3 X 10(-5) s-1), gamma-cleavage of 1 with ring opening to yield mercapto acid 4 (k3 = 0.35 X 10(-5) s-1), and hydrolysis of 2 with ring opening to give 4 (k4 = 1.9 X 10(-5) s-1). The isomerization rate ratio (k1/k-1 = 10.9) agreed with the isomer ratio at equilibrium (1:2 = 11 starting from 1 and 10 starting from 2). The alpha/gamma regioselectivity ratio (k2/k3 = 9.7) for hydrolysis of the internal Glp residue of 1 was consistent with results for model tripeptides. Part of the chemistry of the protein metastable binding sites can be explained by similar isomerization and hydrolysis reactions.

Sequence-specific interaction between the replication initiator protein of plasmid pT181 and its origin of replication

The replication of the pT181 plasmid is dependent on the plasmid-encoded initiator protein RepC. We have previously shown that RepC protein has sequence-specific endonuclease and topoisomerase-like activities. In this paper we demonstrate that this initiator protein has sequence-specific DNA-binding properties. Based on filter binding of plasmid restriction fragments, RepC protein specifically recognizes only the pT181 origin region. Using DNase I and neocarzinostatin "footprinting" techniques, we show that RepC protein specifically binds to a 32-base-pair sequence within the origin that is part of the initiator cistron. Using dimethyl sulfate as a chemical probe, we have identified the purine residues that interact with the initiator protein. The features of the DNA region that interacts with RepC protein include sequences with the potential to form Z DNA and/or hairpin structures. The specific DNA-protein interaction at the origin may be critical in the initiation of pT181 DNA replication by RepC protein in association with other host initiation proteins.

Antigenic specificity of a rabbit antiserum raised against the 15-28 segment of thymosin alpha 1

Thymosin alpha 1, an acidic 28-residue peptide, enhances immune function. We have described a radioimmunoassay for this thymic factor based on a rabbit antiserum raised against a thymosin alpha 1-(15-28) conjugate (Incefy et al., J. Immun. Meth. 1986, in press). The detailed antigenic specificity of this antiserum was determined by measuring the ability of synthetic segments and analogues of thymosin alpha 1 and related peptides to compete with radioiodinated Ac-Tyr-thymosin alpha 1-(15-28) in this radioimmunoassay. The antiserum bound segments Ac-(1-28), (15-28), (20-28) and (21-28) with nearly equal efficiency but failed to bind segments Ac-(1-10), (11-20), (19-24) and (22-28). Thus, the major immunoreactive site seen by the antiserum is the COOH-terminal segment (21-28) (Glu-Val-Val-Glu-Glu-Ala-Glu-Asn-OH). Immunoreactivity of (21-28) was nearly abolished when the carboxylate groups of Glu-21, Glu-27 and Asn-28 were omitted separately. The antiserum bound to prothymosin alpha and thymosin alpha 11, which lack the alpha-carboxylate group of Asn-28, with 0.9 and 0.2%, respectively, of the efficiency of thymosin alpha 1. But it bound nonspecifically to parathymosin alpha, which contains the internal segment . . . -Glu-Val-Val-Glu-Glu-Glu-Glu-Asn- . . . . Residues Glu-21, Glu-27 and Asn-28 of thymosin alpha 1 may be important features of the antigenic site through their ability to induce helical structure, through the ability of their negatively charged carboxylate groups to bind to specific sites on the antibody or both.

Nucleotide sequence of the enterotoxin B gene from Staphylococcus aureus

The complete nucleotide sequence of the enterotoxin B gene from Staphylococcus aureus, as well as the 5' and 3' flanking regions, was determined. Starting from an ATG initiator codon, an open reading frame encoded the enterotoxin B precursor that consisted of 266 amino acids (Mr, 31,400). The 5' terminal portion of the gene encodes a signal peptide 27 amino acids long. The deduced amino acid sequence matched, with a few exceptions, the published amino acid sequence of enterotoxin B. The structural gene was flanked on the 5' side by a promoter-like sequence and on the 3' side by a palindromic structure followed by a thymine-rich region that resembled a transcription termination signal. Downstream from the entB gene were two overlapping open reading frames corresponding to 134 and 185 amino acids in the opposite orientation. The signal sequence of the enterotoxin B precursor resembled that of other secreted proteins found in other bacteria.

Relationship of blood groups and bladder cancer

A retrospective study correlating the blood groups of 141 patients with bladder cancer showed that patients with blood group A had lower grade tumors with lower mortality rates, and those with blood group O(H) had higher grade tumors and higher mortality rates.

The replication initiator protein of plasmid pT181 has sequence-specific endonuclease and topoisomerase-like activities

Initiation of pT181 DNA replication specifically requires the plasmid-encoded RepC protein. Here we demonstrate that highly purified RepC protein has sequence-specific endonuclease and topoisomerase-like activities. A maximum sequence of 127 base pairs containing the pT181 origin of replication is required for nicking-closing by RepC protein. RepC introduces a single strand break within the pT181 origin. The nick site has been shown by DNA sequencing to lie between nucleotides 70 and 71 in the bottom strand of the DNA within the origin sequence. This nick site probably corresponds to the start site of pT181 replication. The results presented here suggest that, unlike most other plasmids, pT181 replicates by a rolling circle mechanism.

Molecular cloning of staphylococcal enterotoxin B gene in Escherichia coli and Staphylococcus aureus

We have cloned the Staphylococcus aureus entB gene in Escherichia coli, using pBR322 as the vector plasmid; however, no detectable staphylococcal enterotoxin B (SEB) was produced by the E. coli clones. When the entB gene was placed downstream from the strong lambda phage promoter, PR, SEB was synthesized at readily detectable levels in E. coli. Interestingly, mature SEB was almost exclusively present in the cytoplasmic fraction. The SEB precursor was found associated with the cell membrane. The entB gene was introduced back into S. aureus, and the clones were shown to produce SEB. The entB gene has been located to a 2.1-kilobase-pair region. Maxam-Gilbert sequencing of a part of the entB gene yielded a DNA sequence that corresponds to the known amino acid sequence of SEB. Southern hybridization experiments showed that the entB gene was present on identical restriction fragments in the chromosomes of SEB-producer strains. The entB gene is absent from SEB-nonproducer strains.

Purification of pT181-encoded repC protein required for the initiation of plasmid replication

The plasmid pT181 of Staphylococcus aureus consists of 4437 base pairs and encodes resistance to tetracycline. Initiation of pT181 replication specifically requires the plasmid-encoded repC protein. An in vitro system has been shown to carry out semiconservative replication of pT181 and its derivative plasmids (Khan, S A., Carleton, S. M., and Novick, R. P. (1981) Proc. Natl. Acad. Sci. U. S. A. 78, 4902-4906). We have used this replication assay to isolate repC protein, which was purified to near homogeneity. The repC gene was cloned into the pKJB825 plasmid that contains the phage lambda temperature-sensitive repressor gene, cI857, and the rightward promoter, PR. Upon temperature induction, Escherichia coli clones containing the recombinant plasmid overproduced repC protein, which was purified in significant quantities. The molecular weight of repC protein under denaturing conditions is 38,000, which is consistent with the size predicted from the DNA sequence data. Presence of repC protein was absolutely essential for the initiation of replication of pT181 and its derivatives in vitro.

Gangrene of male external genitalia in a patient with colorectal disease. Anatomic pathways of spread

This is the report of a patient with gangrene of the skin and subcutaneous tissue of the scrotum and base of the penis secondary to diverticulitis of the sigmoid colon. Due to high mortality in such patients, the early, rapid, and radical debridement of all devitalized tissues and prompt recognition of the source of sepsis is of utmost importance. Computed tomography (CT) scanning facilitates delineating the extent of disease. Anatomy of the perineal body and pathways of spread are discussed.

Stage-specific inhibition of interstitial cell testosterone secretion by rat seminiferous tubules in vitro

The stage-specific influence of the secretions from rat seminiferous tubules on the LH-stimulated testosterone production by rat Leydig cells in vitro was studied. The spent media from incubated seminiferous tubules (SMST) from stages VII-VIII of the seminiferous epithelial cycle caused about 50% inhibition of the LH-dependent testosterone production by a crude preparation of rat interstitial cells. The SMST from other stages had no effect on testosterone production. Mixed tubules of unidentified stages gave an intermediate response. When SMST from ten different stages of the seminiferous wave were compared, the most pronounced inhibitory activity was found in stages VI and VIII-XI, while SMST from stages I, VII and XIII-XIV had no inhibitory effects on interstitial cell testosterone production. No stimulation was found in this system. Prolonged incubation of the interstitial cells with SMST from stages VIII-XI resulted in loss of inhibitory activity after 12 h of incubation. Maximum inhibitory activity was noted after 3 h of incubation. The inhibitory activity of the SMST from stages VIII-XI was retained after prolonged dialysis, and was unchanged after heating the medium at 60 degrees C for 1 h. The activity did not seem to be due to the presence of proteolytic enzymes, since it was not influenced by addition of protease inhibitors. SMST from stages VIII-XI had no effect on the metabolism of [3H]testosterone added to the interstitial cell preparations. No inhibitory effect was observed when Leydig cells were incubated with dibutyryl cAMP instead of LH, suggesting an early influence on the LH-receptor-adenylate cyclase chain of events.(ABSTRACT TRUNCATED AT 250 WORDS)

Nucleotide sequence and organization of the mouse adenine phosphoribosyltransferase gene: presence of a coding region common to animal and bacterial phosphoribosyltransferases that has a variable intron/exon arrangement

We have determined the nucleotide sequence of a functional mouse adenine phosphoribosyltransferase (APRT) gene and its cDNA. The amino acid sequence of the enzyme is deduced from an open reading frame in the cDNA and predicts a protein with a molecular weight of 19,560. The protein coding region of the gene is approximately 2 kilobases, and it is composed of five exons and four introns. While the body of the gene is 53% G + C, the 200 nucleotides upstream from the ATG translation start codon are 66% G + C and contain three copies of the sequence C-C-G-C-C-C. The mouse APRT enzyme shares a homologous 20-amino acid sequence with mouse, hamster, and human hypoxanthine phosphoribosyltransferases (HPRTs) and several bacterial phosphoribosyltransferases. This sequence has previously been shown to be a likely catalytic domain in human HPRT and Escherichia coli glutamine phosphoribosyltransferase. Because of the similarities in function of these proteins, both eukaryotic and prokaryotic, it is not unexpected that they should exhibit one or more regions of homology, particularly at the 5-phosphoribosyl-1-pyrophosphate and purine binding sites, especially if they are related via a common evolutionary lineage. This homologous sequence is interrupted by a single intron in the mouse APRT gene and by two introns in the mouse HPRT gene. Furthermore, the positions of both introns in the HPRT sequence are different from that of the single intron in the corresponding sequence of the APRT gene.

Unusual extraperitoneal presentations of diverticulitis

Extraperitoneal presentations of complicated diverticular disease are unusual. The initial clinical presentations of these extraperitoneal manifestations have been described in the perineum, scrotum, buttock, hip, joints, thigh, lower extremities, mediastinum, and neck. These presentations render the diagnosis difficult and may lead to the delay of the proper therapy. The purpose of this report is to call attention to these unusual extraperitoneal presentations of complicated diverticular disease to describe the routes of spread and to present a case in point. Reviewing the literature, we have concluded that these unusual presentations occur more commonly in women and the elderly, that a delayed diagnosis significantly increases the mortality rate, and that the most common site of an extraperitoneal presentation is in the area of the hip.