A novel approach to nonsurgical sterilization; application of menadione-modified gonocyte-targeting M13 bacteriophage for germ cell ablation in utero

There remains a compelling need for the development of nonsurgical sterilizing agents to expand the fertility management options for both domestic and feral animal species. We hypothesize that an efficacious sterilization approach would be to selectively ablate nonrenewable cell types that are essential for reproduction, such as the undifferentiated gonocytes within the embryonic gonad. Here, we report a novel strategy to achieve this goal centered on the use of a chemically modified M13 bacteriophage to effect the targeted delivery of menadione, a redox‐cycling naphthoquinone, to mouse gonocytes. Panning of the M13 random peptide ‘phage display library proved effective in the isolation of gonocyte‐specific targeting clones. One such clone was modified via N‐succinimidyl‐S‐acetylthioacetate (SATA) linkage to the N‐terminus of the major PVIII capsid protein. Subsequent deacetylation of the SATA was undertaken to expose a thiol group capable of reacting with menadione through Michael addition. This chemical modification was confirmed using UV spectrophotometry. In proof‐of‐concept experiments we applied the modified ‘phage to primary cultures of fetal germ cells and induced, an approximately, 60% reduction in the viability of the target cell population. These studies pave the way for in vivo application of chemically modified M13 bacteriophage in order to achieve the selective ablation of nonrenewable cell types in the reproductive system, thereby providing a novel nonsurgical approach the regulation of fertility in target species.

Anaphylaxis to Cisatracurium following Negative Skin Testing

General anaesthesia for the patient with a history of anaesthesia-related anaphylaxis is challenging. Precautions against anaphylaxis and the use of skin test negative drugs can reduce but not eliminate the risk. In the majority of such cases, subsequent anaesthesia is uneventful. However, the absence of a clearly identified triggering agent increases the difficulties facing the anaesthetist. We present a case of anaphylaxis to cisatracurium following a negative skin test.

RNA binding protein Musashi-1 directly targets Msi2 and Erh during early testis germ cell development and interacts with IPO5 upon translocation to the nucleus

Controlled gene regulation during gamete development is vital for maintaining reproductive potential. During the process of gamete development, male germ cells experience extended periods of inactive transcription despite requirements for continued growth and differentiation. Spermatogenesis therefore provides an ideal model to study the effects of posttranscriptional control on gene regulation. During spermatogenesis posttranscriptional regulation is orchestrated by abundantly expressed RNA-binding proteins. One such group of RNA-binding proteins is the Musashi family, previously identified as a critical regulator of testis germ cell development and meiosis in Drosophila and also shown to be vital to sperm development and reproductive potential in the mouse. We focus in depth on the role and function of the vertebrate Musashi ortholog Musashi-1 (MSI1). Through detailed expression studies and utilizing our novel transgenic Msi1 testis-specific overexpression model, we have identified 2 unique RNA-binding targets of MSI1 in spermatogonia, Msi2 and Erh, and have demonstrated a role for MSI1 in translational regulation. We have also provided evidence to suggest that nuclear import protein, IPO5, facilitates the nuclear translocation of MSI1 to the transcriptionally silenced XY chromatin domain in meiotic pachytene spermatocytes, resulting in the release of MSI1 RNA-binding targets. This firmly establishes MSI1 as a master regulator of posttranscriptional control during early spermatogenesis and highlights the significance of the subcellular localization of RNA binding proteins in relation to their function.

MHC class IIB additive and non-additive effects on fitness measures in the guppy Poecilia reticulata

The genetic architecture of fitness at the class IIB gene of the major histocompatibility complex (MHC) in the guppy Poecilia reticulata was analysed. Diversity at the MHC is thought to be maintained by some form of balancing selection; heterozygote advantage, frequency-dependent selection or spatially and temporally fluctuating selection. Here these hypotheses are evaluated by using an algorithm that partitions the effect of specific MHC allele and genotypes on fitness measures. The effect of MHC genotype on surrogate measures of fitness was tested, including growth rate (at high and low bulk food diets), parasite load following a parasite challenge and survival. The number of copies of the Pore_a132 MHC allele was inversely related to infection by Gyrodactylus flukes and it appeared to be positively related to faster growth. Also, genotypes combining the Pore_a132 or other relatively common alleles paired with rare MHC alleles produced both advantageous and detrimental non-additive effects. Thus, the genetic architecture underlying fitness at the MHC is complex in the P. reticulata.

Lack of morphological differentiation in eastern (Rhinichthys atratulus) and western (Rhinichthys obtusus) blacknose dace in Canada

We tested whether eastern (Rhinichthys atratulus (Herman, 1804)) and western (Rhinichthys obtusus Agassiz, 1854) blacknose dace could be differentiated in Canada. Eastern, western, and southern forms of blacknose dace had been considered subspecies until recently, when separation of eastern and western species was accepted (J.S. Nelson et al. 2004. Am. Fish. Soc. Spec. Publ. No. 29). However, no study has examined morphological differences in purported diagnostic characters between the two species in Canada. Mensural, meristic, and colouration pattern characters purported to distinguish the two species were measured for blacknose dace across their Canadian range, including likely zones of sympatry. Univariate and multivariate analyses of morphological characters could not distinguish between individuals in allopatric populations from eastern and western regions. Variation among individuals within sympatric populations did not differ significantly from the variation among individuals within allopatric populations, providing no evidence of divergence of the species in sympatry. The delineation of eastern and western species using morphology is not supported by this study, given the lack of differentiation in key distinguishing characters within the Canadian range of the species.

Development of a physical characteristics assessment (PCA): a checklist for determining appropriate computer access for individuals with cerebral palsy

The physical characteristics assessment (PCA), a newly developed illustrated checklist, is designed for use by allied health and education professionals to identify a viable method for an individual with cerebral palsy to access a computer. The PCA was developed in response to a documented void of such assessments in the literature. The value of PCA was assessed with respect to content validity, clinical utility, reliability (inter-rater), and opinion of persons with cerebral palsy and health and education professionals. Professionals (n = 72) and persons with cerebral palsy (n = 78) from 20 sites in Canada, Chile, England, Israel, Spain, and the United States participated in the study. Statistically, the PCA produced a highly significant (p < 0.001) assessment time savings compared with non-PCA methods. A statistically significant difference in the number of user/computer interface changes during five post-assessment computer training sessions was not shown between the PCA and non-PCA methods. Inter-rater reliability ranged between 90% and 100% (n = 33 pairs). Both persons with cerebral palsy assessed via the PCA and professionals using the PCA gave positive opinions. Overall results support the value of the PCA.

HPLC purification and separation of 5,5'-substituted-2,4-imidazolidinedithiones

Several 5,5'-substituted-2,4-imidazolidinedithiones, synthesized from aldehydes or ketones, have been purified by HPLC using poly(styrene-divinylbenzene) packings. Purified 5,5'-substituted-2,4-imidazolidinedithiones have been identified in column effluent by UV absorbance and corroborated by mass spectrometry. Several silica-based, polymeric, and poly(styrene-divinylbenzene)-based packings were evaluated as matrices for resolution of a mixture of purified 5,5'-substituted-2,4-imidazolidinedithiones.

Identification of alpha-carboxamidated and carboxy-terminal glycine forms of peptides in bovine hypothalamus, bovine pituitary and porcine heart extracts

Two chemical assays have been developed for identifying and quantifying peptides which either could be biologically active by virtue of their alpha-carboxamidation or could be substrates for peptidylglycine alpha-amidating mono-oxygenase. The first assay is specific for the alpha-carboxamide of peptides. Using bis[trifluoroacetoxy]iodobenzene, the alpha-carboxamide was converted via a Hoffman reaction into a primary amine, which was then quantified by ninhydrin. The second assay is specific for glycine at the carboxy-terminus of a peptide. Glycine at the carboxy-terminus was derivatized to form 2-thiohydantoin, which was then separated and quantified by reverse phase HPLC. These assays were used to detect peptides in HPLC-separated extracts of bovine hypothalamus, bovine anterior lobe pituitary and porcine heart which may be of biological interest.

Isolation and identification of a novel peptide from the accessory sex gland of the female house fly, Musca domestica

A peptide of novel structure was isolated from accessory glands of the female house fly, Musca domestica by molecular-weight limit centrifugal ultrafiltration and reversed-phase HPLC. After amino acid and protein sequence analyses, the structure of this peptide was confirmed by chemical synthesis and plasma desorption mass spectral analysis to be Leu-Leu-Asn-Ala-Leu-Pro-Leu-Asp-Ala-Leu-Ser-Ser-Leu-Thr-Gly-NH2. The accessory gland peptide stimulated contraction of the house fly oviduct at concentrations of 10(-7) M and above.

Single photon emission computerized tomography in obsessive compulsive disorder: a preliminary study

Patterns of cerebral perfusion in patients with obsessive compulsive disorder were evaluated using single photon emission computerized tomography. Eleven patients, who satisfied the DSM-III-R criteria and Research Diagnostic Criteria for the disorder, were evaluated using the distribution of 99m-Tc-HMPAO as a radiotracer. The Yale-Brown Obsessive Compulsive Scale was administered to each patient to assess the severity of their symptoms. The images obtained were evaluated qualitatively and semi-quantitatively by a physician in nuclear medicine who was blind to the patients' diagnoses. Eight of the 11 patients demonstrated asymmetric perfusion of the basal ganglia; the left side showed impaired perfusion in six patients.

Primary structure of two neuropeptide hormones with adipokinetic and hypotrehalosemic activity isolated from the corpora cardiaca of horse flies (Diptera)

The primary structures of two neuropeptides, Tabanus atratus adipokinetic hormone (Taa-AKH) and Tabanus atratus hypotrehalosemic hormone (Taa-HoTH), from the corpora cardiaca of horse flies (Diptera: Tabanidae) have been determined. Amino acid sequences of Taa-AKH (less than Glu-Leu-Thr-Phe-Thr-Pro-Gly-Trp-NH2) and Taa-HoTH (less than Glu-Leu-Thr-Phe-Thr-Pro-Gly-Trp-Gly-Tyr-NH2) (where less than Glu = pyroglutamic acid) were determined by automated gas-phase Edman degradation of the peptides deblocked by pyroglutamate aminopeptidase and by fast atom bombardment mass spectrometry. The hormones were synthesized, and the natural and synthetic peptides exhibited identical chromatographic, spectroscopic, and biological properties. When assayed in adult face fly males, Taa-AKH and Taa-HoTH demonstrated hyperlipemic activity, in addition, Taa-HoTH also demonstrated a significant hypotrehalosemic activity.

Morphological sex differentiation in the human embryo: A light and scanning electron microscopic study

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Surgical management of the severely multiply handicapped individual

Thirty-four surgical procedures were performed over a 12-year period on a select population of severely multiply handicapped individuals. Heel cord lengthening, hamstring and adductor releases, as well as selected osteotomies, tenotomies, and arthrodeses (both wrist and foot) were performed. The objectives were improvement in sitting posture, care, and comfort. Independent evaluations of active function, passive function, cosmesis, self-esteem, limb posture, and ease of dressing and hygiene were assessed. Significant improvement was generally noted. No patient was made worse. Selected procedures in the severely multiply handicapped individual have a definite place in patient management.

cDNA sequence of rat liver fructose-1,6-bisphosphatase and evidence for down-regulation of its mRNA by insulin

A coding-length clone of rat liver fructose-1,6-bisphosphatase (EC 3.1.3.11) was isolated by immunological screening of a cDNA library in lambda gt11. Its identity was verified by comparing the deduced amino acid sequence with that obtained by direct sequencing of a complete set of CNBr and proteolytic peptides from the purified protein. The enzyme subunit is composed of 362 amino acids and has N-acetylvaline as the amino-terminal residue. The cDNA, 1255 base pairs (bp) long, consisted of 1086 bp of coding region, 15 bp of 5' untranslated sequence, and 154 bp at the 3' untranslated end. The 3' untranslated sequence contained a polyadenylylation signal (AATAAA) followed after 30 bp by a stretch of 7 adenines at the end of the clone. The deduced amino acid sequence was identical to the primary sequence of the protein and confirmed the alignment of five nonoverlapping peptides. It also confirmed the 27-residue extension, unique to the rat liver subunit, ending with a carboxyl-terminal phenylalanine. RNA blot analyses using the radiolabeled liver cDNA as a probe revealed a single band of fructose-1,6-bisphosphatase mRNA, 1.4 kilobases long, in liver and kidney but not in nongluconeogenic tissues. Fructose-1,6-bisphosphatase mRNA was increased 10-fold in livers from diabetic rats and was reduced to control levels after 24 hr of insulin treatment, suggesting that the changes in enzyme activity observed in diabetes and after insulin treatment are due to alterations in mRNA abundance.

Isolation and primary structure of a neuropeptide hormone from Heliothis zea with hypertrehalosemic and adipokinetic activities

A neuropeptide was isolated from the corpora cardiaca of the corn earworm moth Heliothis zea, and purified by sequential gradient elution in three reversed phase-high performance liquid chromatographic steps. The primary structure, pGlu-Leu-Thr-Phe-Ser-Ser-Gly-Trp-Gly-Asn-NH2 was determined by automated gas-phase Edman degradation of the peptide deblocked with pyroglutamate aminopeptidase, and confirmed by fast atom bombardment mass spectrometry. The hormone was synthesized and the natural and synthetic peptides had identical chromatographic and spectroscopic properties. Both natural and synthetic hormones caused the elevation of trehalose and lipid levels in the hemolymph of adult H. zea males.

Isolation of two neuropeptides in the AKH/RPCH-family from horseflies (Diptera)

Two neuropeptides (DCCI and DCCII) in the adipokinetic/red pigment concentrating hormone-family have been isolated and purified from the corpora cardiaca of horseflies (Diptera : Tabanidae). Both peptides were purified by a sequence of three reversed phase-high performance liquid chromatographic steps. Amino acid analysis of the purified peptides indicated the following composition for DCCI: Glx(l), Gly(1), Leu(1), Phe(1), Pro(1), Thr(2) and for DCCII: Glx(1), Gly(2), Leu(1), Phe(1), Pro(1), Thr(2), and Tyr(1). Photodiode array ultraviolet spectroscopy indicated the presence of tryptophan in both DCCI and II. Both DCCI and II had red pigment concentrating hormone activity in the crab, Uca pugilator.

Complete amino acid sequence of rat liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase

The complete amino acid sequence of 6-phospho-fructo-2-kinase/fructose-2,6-bisphosphatase from rat liver was determined by direct analysis of the S-carboxamidomethyl protein. A complete set of nonoverlapping peptides was produced by cleavage with a combination of cyanogen bromide and specific proteolytic enzymes. The active enzyme is a dimer of two identical polypeptide chains composed of 470 amino acids each. The NH2-terminal amino acid residue of the polypeptide chain was shown to be N-acetylserine by fast atom bombardment mass spectrometry of the purified N-terminal tetradecapeptide isolated after cleavage of the intact S-carboxamidomethylated protein with lysyl endoproteinase (Achromobacter protease I). Alignment of the set of unique peptides was accomplished by the analysis of selected overlapping peptides generated by proteolytic cleavage of the intact protein and the larger purified cyanogen bromide peptides with trypsin, Staphylococcus aureus V8 protease, and lysyl endoproteinase. Four nonoverlapping peptides were aligned by comparison with the amino acid sequence predicted from a partial cDNA clone encoding amino acid positions 166-470 of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (Colosia, A.D., Lively, M., El-Maghrabi, M. R., and Pilkis, S. J. (1987) Biochem. Biophys. Res. Commun. 143, 1092-1098). The nucleotide sequence of the cDNA corroborated the peptide sequence determined by direct methods. A search of the Protein Identification Resource protein sequence database revealed that the overall amino acid sequence appears to be unique since no obviously homologous sequences were identified. However, a 100-residue segment of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (residues 250-349), including the active site histidine residue of the bisphosphatase domain, was found to be homologous to the active site regions of yeast phosphoglycerate mutase and human bisphosphoglycerate mutase.

Effect of culture conditions on the structure of Streptococcus pneumoniae type 19A(57) capsular polysaccharide

The structural modifications and immunochemical activities of several Streptococcus pneumoniae type 19A polysaccharide (PS) preparations have been studied by sugar compositional analysis and immunodiffusion. The 19A PS preparations Lab-A-1 and Lab-A-3 and one PS isolated from 19A strain OB contained fucose (Fuc) and galactose (Gal) in addition to rhamnose (Rha) and glucose (Glc). In contrast, 19A PSs Lab-A-2 and Lab-B contained only Rha and Glc. Despite their different sugar compositions, these 19A preparations appeared to be identical in serologic activity as measured by immunodiffusion with rabbit 19A and 19F antisera. The 19A PS Lab-A-1 was separated into three fractions by DEAE-Sepharose CL-6B column chromatography with a NaCl gradient. Fraction II was the major peak with a yield of 72.9%. Fraction Ia contained Fuc and Gal, while fraction II contained Fuc, Gal, Rha, and Glc. Fractions Ia and Ib did not react with rabbit 19A antiserum. In contrast, 19A PS Lab-A-2 displayed only one peak, which was eluted by a NaCl gradient (0 to 0.6 M NaCl), and contained only Rha and Glc. The 19A PSs prepared from Lab-A and Centers for Disease Control (CDC) strains and grown in pneumococcal inoculum medium (PIM) and modified Holt medium were chromatographed on a DEAE-Sepharose CL-6B column, and the separated fractions were examined for their sugar composition. The fractions obtained from the 19A PSs Lab-A-PIM and CDC-PIM exhibited four sugar components, as observed for the PS Lab-A-1, while the separated fractions from the 19A PSs Lab-A-Holt and CDC-Holt displayed two sugar components, a pattern similar to that of PS Lab-A-2. Thus, the sugar compositions of 19A PS appeared to vary according to the type of culture medium used to grow the 19A organisms.

Use of immobilized exopeptidases and volatile buffers for analysis of peptides by fast atom bombardment mass spectrometry

beta-Lipotrophin (62-77) or Ac-gastrin releasing peptide was incubated with immobilized carboxypeptidase Y or aminopeptidase M. Subsequent aliquots of each incubation mixture were analysed by fast atom bombardment mass spectrometry using a dithiothreitol/dithioerythritol liquid matrix. The use of immobilized enzymes and volatile buffers for exopeptidase digestions enabled rapid and facile separation of enzyme from digestion products. This approach to mass spectral peptide analysis reduced spectral background arising from a glycerol matrix, buffer salts, or enzyme proteins and contaminants, enabling analysis of as little as 200 picomoles of a suitable peptide.

Analysis of peptides containing oxidized methionine and/or tryptophan by fast atom bombardment mass spectrometry

Treatment of peptides containing methionine and/or tryptophan with dimethylsulfoxide/hydrochloric acid/acetic acid resulted in oxidation of these amino acids respectively to methionine sulfoxide and oxyindolalanine. This reaction was monitored by fast atom bombardment mass spectrometry using a dithiothreitol/dithioerythritol liquid matrix. Under these conditions, only methionine and tryptophan were oxidized. Comparison of mass spectra of a sample before and after oxidation should provide a rapid screening procedure for determination of these residues in peptides.

Structural evidence that endothelial cell growth factor beta is the precursor of both endothelial cell growth factor alpha and acidic fibroblast growth factor

Two endothelial cell growth factors (ECGF) have been purified from bovine brain and termed alpha- and beta-ECGF [Burgess, W. H., Mehlman, T., Friesel, R., Johnson, W. V. & Maciag, T. (1985) J. Biol. Chem. 260, 11389-11392]. Amino acid sequence analysis indicates that beta-ECGF represents a 20 amino acid amino-terminal extension of alpha-ECGF and a 14 amino acid amino-terminal extension of acidic fibroblast growth factor. These data indicate that both alpha-ECGF and acidic fibroblast growth factor may be derived from beta-ECGF by posttranslational processing. Analysis of the amino-terminal 14 residues of beta-ECGF by fast-atom-bombardment mass spectrometry established the amino acid sequence of this region and the identity of the blocking group at the amino terminus (acetyl).

Primary structure of gonadotropin-releasing hormone from lamprey brain

The primary structure of gonadotropin-releasing hormone (GnRH) isolated from whole brains of lamprey is pGlu-His-Tyr-Ser-Leu-Glu-Trp-Lys-Pro-Gly-NH2. This unique decapeptide was isolated and purified from brain extracts by reverse-phase high performance liquid chromatography. The structure of the peptide was established from chymotryptic fragments that were identified by protein sequence analysis and fast atom bombardment mass spectrometry. The peptide reacts with an antiserum raised against mammalian GnRH and is structurally identified as a member of the GnRH family by the amino and carboxyl termini of pGlu1-His2 and Pro9-Gly10NH2, the conservation of Ser4 in the internal segment of the molecule and its length of 10 amino acids. For the first time, amino acid substitutions are found in positions 3 and 6, critical for biological potency and conformation, respectively. Additionally, a second form of GnRH (lamprey II GnRH), representing about 10% of the total GnRH immunoreactive material in the brain, was isolated; its amino acid composition differs by 3 residues from lamprey I GnRH. Synthetic lamprey I GnRH elevates plasma estradiol in adult female lampreys.

Isolation and primary structure of a peptide from the corpora cardiaca of Heliothis zea with adipokinetic activity

An adipokinetic hormone was isolated from the corpora cardiaca of the corn ear worm moth, Heliothis zea, and purified by reversed phase high performance liquid chromatography. The primary structure, pGlu-Leu-Thr-Phe-Thr-Ser-Ser-Trp-Gly-NH2, was determined by automated gas-phase Edman degradation of the peptide deblocked with pyroglutamic aminopeptidase, and by fast atom bombardment mass spectrometry. The hormone was synthesized and the natural and synthetic material had identical chromatographic, spectroscopic, and biological properties. The peptide was found to have lipid mobilizing activity in H. zea adults.

Vasculogenesis and chondrogenesis in the chick wing bud

Stage 22 to stage 24 chick wing buds were labeled with sulphate-35 to identify chondrogenic areas; these areas were then related to the presence of blood vessels. Blood vessels were found in areas of increased sulphate uptake, indicating that there is no avascular area formed in the limb bud mesenchyme prior to the onset of chondrogenesis, as indicated by increased sulphate-35 uptake. It is, therefore, unlikely that the vasculature plays an initial role in the determination of chondrogenic areas in the wing bud.

Peptide studies using a fast atom bombardment high field mass spectrometer and data system. 4. Disulfide-containing peptides

Ten peptides containing one, two or three disulfides were examined to determine their behavior under fast atom bombardment (FAB) mass spectrometric conditions. The mass spectra for the disulfide and the reduced disulfide forms of each peptide were compared. Several factors were examined that contribute to the fast atom bombardment mass spectra of these peptides: components of the FAB matrix such as alkali cations, acids, bases and reducing agents, the intrinsic molecular properties of the intact peptide, and the effect of reducing conditions on sensitivity. The FAB mass spectra of the disulfide-containing peptides examined in this study displayed accurate molecular weight information and fragmentation which indicated the position of the disulfide in the amino acid sequence.

Synthesis and fast-atom-bombardment-mass spectrometry of N-acetylmuramoyl-L-alanyl-D-isoglutamine (MDP)

N-Acetylmuramoyl-L-alanyl-D-isoglutamine (MDP) was synthesized by a series of condensations of appropriate reagents, followed by hydrogenolysis. Each intermediate step resulted in a stable, crystalline product. D-Isoglutamine 4-benzyl ester was condensed with N-(tert-butoxycarbonyl)-L-alanine N-hydroxysuccinimide ester, to give N-(tert-butoxycarbonyl)-L-alanyl-D-isoglutamine benzyl ester. Condensation of L-alanyl-D-isoglutamine benzyl ester with N-acetyl-1-O-benzyl-4,6-O-benzylidenemuramic acid, followed by hydrogenolysis, gave MDP. The synthetic scheme was shown to be capable of producing gram quantities of highly pure MDP, as well as a few of its analogs. The synthetic MDP was characterized by analytical and biological methods, and it was found that the use of fast-atom-bombardment-mass spectrometry may greatly simplify the characterization process.

The mixed disulfide in the zymogen of streptococcal proteinase. Characterization and implication for its biosynthesis

The identity of the volatile mercaptide and the metabolic pathway by which it becomes combined with the zymogen of streptococcal proteinase in the mixed disulfide were investigated. Mass spectrometric analysis identified the oxidized form of the volatile mercaptan as methanesulfonic acid. The mass spectrum of a peptide isolated from tryptic and subsequent chymotryptic digests of the zymogen was shown to be consistent with the previously reported amino acid sequence for a chymotryptic peptide with the sequence Val-Gly-Gln-Ala-Ala-Thr-Gly-His-Cys(SCH3)-Val. Studies using [35S] cystine, [methyl-35S]methionine and [methyl-14C]methionine in a cell suspension system revealed that the biosynthesis of the mixed disulfide in the zymogen may involve the formation of protein-S-SH followed by transmethylation rather than result from a direct transfer of an intact methanethiol to the cysteinyl residue of the zymogen. It is proposed that the attachment of the CH3-SH group to the protein-SH to form protein-S-S-CH3 is a process that is intimately related to the mechanism of secretion of the proteinase into the culture fluid by streptococci.

ADP-ribosylation of transducin by islet-activation protein. Identification of asparagine as the site of ADP-ribosylation

Islet-activating protein catalyzes the ADP-ribosylation of transducin, a guanine nucleotide-binding regulatory protein that mediates activation of a retinal cyclic GMP-selective phosphodiesterase. Radiolabel from [adenylate-32P]NAD+ was incorporated specifically into the alpha subunit of purified transducin. Maximal levels of incorporation approximated 0.8 mol of ADP-ribose/mol of transducin. A peptide containing the ADP-ribosyl moiety was purified from a tryptic digest of radiolabeled transducin. This peptide was characterized by chemical and enzymatic procedures and by fast atom bombardment mass spectrometry. The primary structure of this peptide was Glu-Asn-Leu-Lys-Asn(ADP-ribose)-Gly-Leu-Phe. It is probable that the peptide originated from the carboxyl terminus of the alpha subunit and that the ADP-ribosyl moiety is attached by an N-glycosidic linkage to the asparagine residue. Transducin associated with retinal disc membranes is also ADP-ribosylated by cholera toxin. Cholera toxin and islet-activating protein sequentially catalyze the incorporation of 1.9 mol of ADP-ribose/mol of transducin, indicating two distinct sites of ADP-ribosylation within transducin.

The structure of the repeating oligosaccharide unit of the pneumococcal capsular polysaccharide type 18C

The structure of the repeating oligosaccharide of the pneumococcal capsular polysaccharide type 18C has been investigated. The repeating oligosaccharide, isolated from an aqueous hydrofluoric acid hydrolyzate of the polysaccharide, was shown, by fast atom bombardment-mass spectrometry, to have a molecular weight of 928, and to contain an O-acetyl group and a glycerol residue. Information about the sequence in the per-O-methylated oligosaccharide was derived from electron-impact mass spectrometry. Supporting data were obtained from methylation analysis, periodate and chromium trioxide oxidations, and enzymic and acid hydrolyses of the oligosaccharide. These studies indicated that the polysaccharide consists of the following pentasaccharide repeating unit. (formula see text)

Peptide studies using a fast atom bombardment high field mass spectrometer and data system. 3--Negative ionization: mass calibration, data acquisition and structural characterization

Under negative ionization conditions, nominal mass calibration of the fast bombardment high field mass spectrometer and data system was accomplished using cesium iodide/glycerol as a reference. Mass calibration at --8 kV accelerating potential extends from m/z 387 to m/z 2170 using xenon fast atoms. Negative xenon FAB mass spectra for human angiotensin I and human gastrin I complement their positive fast atom bombardment spectra. Negative xenon fast atom bombardment spectra of underivatized peptides exhibit molecular proton-abstracted ion envelopes and structurally significant fragment ions. Peptide mixture analysis under negative xenon fast atom bombardment reveals peptide molecular ion envelopes of higher relative intensities than under positive xenon fast atom bombardment.

Peptide studies using a fast atom bombardment high field mass spectrometer and data system. 1--Sample introduction, data acquisition and mass calibration

Conditions were established for analyzing as little as 5 pmol of an underivatized peptide delivered in a glycerol sample matrix as a thin film onto a gold-plated copper sample stage and then bombarded with xenon fast atoms. Calibration of the fast atom bombardment high field mass spectrometer and data system was achieved using cesium iodide/glycerol as a reference. Calibration at several accelerating potentials permitted a mass range from 393 to 5941 u. Several factors were examined that contribute to the quality of the mass spectrum: components within the glycerol such as other peptides, alkali salts, acid and reducing agents; the nature of the fast atom gas; concentration of the peptide delivered to the sample stage; and the effect of the sample stage and sample matrix on sensitivity.

Lipid on capsular polysaccharides of gram-negative bacteria

Hydrolysis of the meningococcal group A, B, and C, and Escherichia coli K92 polysaccharides by 60% aqueous hydrofluoric acid liberated various 1,2-diacylglycerols. These were extracted with chloroform, trimethylsilylated, and analyzed by gas chromatography-mass spectrometry. Two 1,2-diacylglycerols were the major components isolated. In each polysaccharide, 80 to 90% dipalmitoyl glycerol and 10 to 20% distearoyl glycerol were identified. No monoacylglycerols or mixed diacylglycerols were noted. The presence of the hydrophobic end causes the polysaccharides to aggregate in a micellar form and may be the entity by which the polysaccharide remains attached to the outer membrane of the bacterium giving rise to the structure recognized as a capsule.

Phospholipid methylation and phospholipase A2 activation in cytotoxicity by human natural killer cells

The role of phospholipid methylation and phospholipase A2 (phosphatide 2-acylhydrolase, EC 3.1.1.4) in natural killer (NK) function by human peripheral blood mononuclear cells was studied. Pretreatment of effector cells with a methyltransferase inhibitor, 3-deazaadenosine, in the presence of homocysteine thiolactone, reduced cytotoxicity in a dose-dependent fashion. This effect was closely associated with inhibition of methylation of lipids but not of nucleic acids or proteins. The suggestion for a role of phospholipid methylation was supported by the observation that the interaction between NK-susceptible tumor targets and peripheral blood mononuclear cells caused increased phospholipid methylation only when susceptible target cells were used. Phospholipase A2 was also implicated in human NK activity. Inhibitors of the enzyme such as tetracaine, mepacrine, Rosenthal's inhibitor, and corticosteroids impaired NK function. Rosenthal's inhibitor was also shown to exert an inhibitory effect on a purified NK-cell population obtained by the isolation of large granular lymphocytes on Percoll gradients. Peripheral blood mononuclear cells were also directly shown to display phospholipase A2-like activity, as measured by the decrease in radioactive arachidonate from prelabeled phospholipids, specifically phosphatidylcholine, in effector cells. These data suggest that enhanced phospholipid methylation occurs during the recognition function of NK cells. Consequent activation of phospholipase A2 might be involved in the mechanisms leading to lytic events within the target cell.

Evaluation of physical therapy service for severely mentally impaired students with cerebral palsy

The effects of two types of physical therapy service were studied over a five-month period in 19 severely mentally impaired cerebral palsied students aged 3 to 22 years. The students were paired and assigned to either a direct therapy treatment group or a supervised therapy management group. Ten similar students in a comparison group received no physical therapy. The study showed no significant difference in development of mature developmental reflexes, improvement of gross motor skills, or increase of passive joint motion among similar students placed in the direct, supervised, and comparison groups. This pilot study is not intended to decide the issue of physical therapy for these students. It does, however, indicate that objective tests may be used reliably to measure three major areas of sensory motor development. More extensive and longer-term studies are needed to determine the most beneficial form of physical therapy for this double-disability population.

Chemical structure of and immune response to polysaccharides of Streptococcus pneumoniae

By use of rabbit antisera, extensive cross-reactions were demonstrated among pneumococcal (Danish) types 6A and 6B, types 9N, 9A, 9L, and 9V, and types 19F and 19A. The structural similarity of the group 6 polysaccharides was associated with extensive immunogenicity in humans. In contrast, immunization of humans with type 19F or 19A may not induce sufficient cross-protection. The type 19F polysaccharide has the structure of a linear polymer of N-acetylmannosamine-glucose-rhamnose phosphate. Danish type 19A (type 57 in the United States system) polysaccharide contains this repeating unit and, in addition, has side chains of N-acetylglucosamine-galactose phosphate and fucose phosphate. Maternal immunization with type 19F or type 6A polysaccharide during pregnancy elicited high antibody formation in the offspring. Young mice, which received an additional dose of polysaccharide at two weeks of age, showed a higher antibody response than did those that did not receive polysaccharide. These studies reveal that the extensive cross-immunogenicity of pneumococcal group polysaccharides has a basis in chemical structure. Maternal immunization with pneumococcal polysaccharides may enhance the immune response of neonates.

The structures of the cross-reactive types 19 (19F) and 57 (19A) pneumococcal capsular polysaccharides

The structures for two cross-reactive capsular polysaccharides isolated from Streptococci pneumoniae types 19 and 57 are proposed based on the analytical data obtained from methylation, enzymatic degradation, and periodate oxidation experiments performed on both intact polysaccharides and oligosaccharides isolated from hydrofluoric acid hydrolysates. Both polysaccharides exhibit an identical structure of 4)-beta-2-acetamido-2-deoxymannose-(1 leads to 4)-alpha-D-glucose-(1 leads to 2)-alpha-L-rhamnose-1-phosphate. This trisaccharide is considered the only repeating unit in the type 19 polysaccharide. The type 57 polysaccharide contains this same repeating unit and side chains composed of a beta-D-2-acetamido-2-deoxyglucose-(1 leads to 3)-beta-D-galactose-1-phosphate side chain attached to C-2 of the glucose and an alpha-L-fucose-1-phosphate attached to C-3 of the rhamnose.

Mass-spectral studies of isomeric D-ribofuranosylribitol disaccharides from the capsular polysaccharides of Haemophilus influenzae type b and Escherichia coli K 100

Two isomeric-D-ribofuranosylribitols, derived from capsular polysaccharides of Haemophilus influenzae type b and Escherichia coli K 100, were methylated or acetylated, and the products analyzed by gas-liquid chromatography-mass spectrometry. The marked difference in the mass spectra of the methyl ethers of these disaccharides allowed clear distinction between 1- and 2-O-D-ribofuranosylribitol was characteristic for this disaccharide; its isomer, the (1 leads to 2)-linked species, has a base peak at m/e 57. The difference in the base peaks is attributable to fragmentation of the methylated ribitol, as both spectra display common ions characteristic of the methylated D-ribofuranosyl group. For the acetylated disaccharides, the mass spectra displayed common ions characteristic of the acetylated D-ribofuranosyl group. However, no ions similar to those found for the methylated ribitol allowed ready differentiation between the two acetates. Instead, their spectra displayed similar ions, differing somewhat in relative abundance; the M-1 ion, m/e 577, was obtained for both. Comparison of the relative abundance of m/e 139, 259, and 303 in the spectra of the two acetates did allow distinction between them.

Ultimobranchial body cysts in the human foetal thyroid: pathological implications

In a histological study of 28 human foetal thyroids, ultimobranchial body cysts were found in seven foetuses. Large oval cells were seen adjacent to or within the cysts. There is a morphological resemblance between the cells associated with the ultimobranchial cysts and those of medullary carcinoma of the thyroid gland. This similarity, in humans, substantiates the hypothesis that medullary carcinoma arises from the parafollicular cells, which themselves are known to differentiate from ultimobranchial body tissue.

Position of ultimobranchial body cysts in the human fetal thyroid gland

In a series of 21 human fetal thyroid glands examined histologically in serial sections, seven ultimobranchial body cysts were found. The position of these cysts correlated well with the distribution of calcitonin-containing cells found by previous investigators in the adult thyroid gland. Ultimobranchial body cysts found external to the thyroid lobes may offer a developmental explanation for the paucity of calcitonin found in some adult thyroid glands. The close developmental relationship between the parathyroid gland and the ultimobranchial body could explain the presence of calcitonin found in these glands in some adults.

The effect of retinoic acid on chondrogenesis in the fetal hamster tibia in vivo

Chondrogenesis in the fetal hamster tibia was examined 24, 36 and 48 h after maternal administration of retinoic acid at a known teratogenic dose (80 mg/kg) on day 10 of gestation. Twenty-four hours after treatment the tibial chondroblasts were more closely packed with less intervening fibrillar or granular matrix than in the controls. By 36 h post treatment, an intercellular matrix containing wide clumped fibrils unassociated with matrix granules had begun to accumulate, while the condroblasts had a relatively poorly developed Golgi apparatus and smooth, non-scalloped cell outlines. Cells frequently maintained contact chondroblasts appeared similar to controls of the same age. It is suggested that the paucity and abnormality of the extracellular matrix prevents the chondroblasts from assuming their normal spatial relations with each other, resulting in a small skeletal blastema.

Rabbit latent group a allotypes: characterization and relationship to nominal group a allotypic specificities

Latent group a allotypes were detected with a sensitive radioimmune inhibition assay. Sera, IgG preparations, and antibody fractions containing these allotypes inhibited the binding of insolubilized allotypic antisera to various radiolabeled antigens including IgG pools, homogeneous antibodies, and, in the case of a3, a VH fragment from a3/b4 IgG. Several different group a antiallotypic sera were used in the assays and all gave similar results. Comparison of inhibition curves for nominal and latent allotypes indicated that the full spectrum of allotypic subspecificities may be expressed in latent allotypes. Hemagglutination studies carried out with five sera containing high levels of latent allotypes confirmed the results obtained with the radioimmunoassay and indicated that inhibition values did not, at least in four of the five samples studied, reflect the presence of antiallotype antibodies.

The relation of aberrant vasculogenesis to skeletal malformation in the hamster fetus

Oral administration of teratogenic doses of retinoic acid to pregnant hamsters on day 10 of gestation is associated with dysmorphogenesis of the appendicular skeleton. During the 24 h following retinoic acid treatment, the developing limb bud vasculature was disorganized, with blood vessels encroaching on areas where mesenchymal condensation of the skeletal blastemata normally occurs. Large, branching marginal folds and endothelial cell vesiculations protruded into the blood vessel lumina. It is suggested that the vascular changes observed may affect the concurrent early development of the skeleton and contribute to the skeletal malformation seen in near-term fetuses.

Variable region correlates of group b allotypes: amino acid sequence studies of b9 L chains from homogeneous antibodies

The amino acid sequence was determined for residues for residues 1 to 88 and residues 110 to 147 for a rabbit light chain (4153-I) with allotype b9 from a homogeneous anti-streptococcal antibody. The amino acid sequence of the L chain from a second antibody (4153-II) was also determined for residues 1 to 49 and 62 to 77. In spite of the large differences in constant region sequence between b4 and b9 L chains, the variable regions of these antibodies are quite similar to those reported for b4 L chains. Both chains bear a b9-specific substitution (glutamic acid) at position 16. The 4153-I chain also has substitutions at positions 70 and 81 that may be exclusive to variable regions of the L chains with the b9 allotype. These allotype-associated VL structural differences offer support to the notion that structural genes for the CL region are either linked to distinct VL gene complexes or that certain V regions are expressed only in concert with certain CL regions.