Three-dimensional structural analysis of the group B polysaccharide of Neisseria meningitidis 6275 by two-dimensional NMR: the polysaccharide is suggested to exist in helical conformations in solution

The solution conformations of the group B polysaccharide of Neisseria meningitidis were analyzed by DQF-COSY and pure absorption 2D NOE NMR with three mixing times. The pyranose ring of the sialic acid residue was found to be in the 2C5 conformation. The DQF-COSY analysis indicated that the orientations of H6 and H7 and of H7 and H8 are both gauche. In order to overcome the difficulties in analyzing the NOE data due to the two sets of proton overlaps, molecular modeling of alpha-2,8-linked sialic acid oligomers was carried out to investigate possible conformers, and theoretical NOE calculations were performed by using CORMA (complete relaxation matrix analysis). Our analysis suggests that the polysaccharide adopts helical structures for which the phi (defined by O6-C2-O8-C8) and psi (C2-O8-C8-C7) angles are in the following ranges: phi -60 to 0 degrees, psi 115-175 degrees or phi 90-120 degrees, psi 55-175 degrees. The weak affinity of anti-B antibodies for smaller alpha-2,8-linked oligosaccharides may be due to the fact that such oligomers are more flexible and may not form an ordered structure as the poly(sialic acid) does.

Meningococcal molecular mimicry and the search for an ideal vaccine

The carbohydrates expressed on the surface of meningococcal strains of groups B and C mimic those commonly found on human cells and thus are not functionally antigenic in infancy. In order to develop an effective vaccine, it will be necessary to find ways of circumventing this molecular mimicry. Three possible ways of achieving this are discussed. (i) The surface polysaccharides can theoretically present conformationally different epitopes, some of which might be recognized as antigenic by the host. Experimental evidence is presented that such differences do indeed exist; what is needed is to determine which of these conformations are unique to the organism and hence potentially antigenic. (ii) Precursors of the surface lipooligosaccharides may be unable to mimic human antigens, and so may be potential candidates for vaccine development. (iii) Natural immunity to some strains of meningococci develops in young children who are colonized with strains of Neisseria lactamica, and it is possible that its development could be enhanced by widespread intentional colonization by N. lactamica strains that are particularly efficient inducers of broad immunity.

Impaired secretion of growth hormone-releasing hormone, growth hormone and IGF-I in elderly men

The GHRH test and L-dopa test were performed in 12 normal young men (24.1 +/- 1.1 years) and 12 normal elderly men (77.8 +/- 1.4 years) to investigate age-related changes in secretion of GHRH, GH and IGF-I. The basal plasma levels of GHRH and GH were not significantly different in young and elderly men, but the basal plasma level of IGF-I was higher in the young men (159.0 +/- 11.7 vs 86.7 +/- 11.6 micrograms/l). The area under the curve for plasma GH in the GHRH test was less in the elderly group (35.1 +/- 5.9 vs 11.2 +/- 2.1 micrograms.h-1.l-1, p less than 0.001). The AUCs for the plasma GHRH and GH responses in the L-dopa test in young and elderly men were 32.0 +/- 2.7 vs 20.3 +/- 1.8 ng.h-1.l-1 (p less than 0.001), and 21.8 +/- 4.6 vs 5.4 +/- 1.1 micrograms.h-1.l-1 (p less than 0.01), respectively, indicating decreased releases of GHRH and GH in the elderly. Correlations between the AUCs for plasma GHRH and GH responses in L-dopa were found in both groups, but the ratio of the AUCs for GH/GHRH was lower in the elderly group. The elderly group showed a significant correlation between the basal plasma IGF-I level and the AUCs for plasma GH in the GHRH and L-dopa tests. These results suggest that elderly men have a decreased reserve of hypothalamic GHRH, resulting in secondarily impaired GH release, which may lead to a lower level of IGF-I than in young men.

TAT-59, a new triphenylethylene derivative with antitumor activity against hormone-dependent tumors

The antiestrogenic action of TAT-59 [(E)-4-[1-[4-[2-(dimethylamino)ethoxy]-phenyl]-2-(4-isopropyl) phenyl-1-butenyl]phenyl monophosphate] was characterized and compared with that of Tamoxifen (TAM). Its active metabolite, 4-OH-TAT-59, had a high binding affinity to estrogen receptor (ER), present in the cytosol of the uterus of immature rat, similar to estradiol. TAT-59 and 4-OH-TAT-59 inhibited in vitro estrogen-stimulated proliferation of MCF-7 cells at a lower concentration than TAM. In the absence of estradiol, TAT-59 and 4-OH-TAT-59 were effective at a lower concentration than that of 4-OH-Tamoxifen (4-OH-TAM), the active metabolite of TAM. In uterine growth inhibition, the effective dose of TAT-59 was about 3-6-fold lower than that of TAM, in various administration schedules. The minimum effective dose of TAT-59 against in vivo MCF-7 cells was about 3-fold lower than that of TAM. In DMBA-induced rat mammary tumors, TAT-59 inhibited the growth of existing tumors at about a 10-fold lower dose than TAM. Especially in the tumors with low ER levels (10-20 fmol/mg protein), TAT-59 showed a significantly stronger inhibitory effect than TAM. These experiments showed that TAT-59 was more effective in lower doses than TAM, even against the tumors with low ER content.

Study on digestibility and energy availability of daily food intake by the Japanese. Part 2. Horse mackerel and milk

Four male Japanese students were fed a semisynthetic diet including rice and whole egg as protein for seven days (basal-diet period), and in the following seven days milk and then, for seven days, horse mackerel were added at the expense of part of the corn starch and sugar in the basal diet (test-diet period). Urine and feces were collected throughout all periods and the contents of protein, fat and energy in these extra were determined. The results obtained were as follows: 1) Digestibility of protein was 97.3 +/- 4.1% for milk and 96.8 +/- 2.8% for horse mackerel. 2) Digestibility of fat was 96.7 +/- 1.9% for milk and 98.6 +/- 2.6% for horse mackerel. 3) The ratio of the total available energy to intake energy (Net Energy Availability) was 92.5 +/- 2.9% for milk and 88.4 +/- 5.2% for horse mackerel.

Evaluation of hypothalamic-pituitary function in a combination of tests with four hypothalamic releasing hormones and L-dopa in normal subjects and in patients with hypothalamic and/or pituitary disorders

Hypothalamic-pituitary function was evaluated in a combination of tests with four hypothalamic releasing hormones (4RHs) and L-dopa in normal subjects and in patients with hypothalamic and/or pituitary disorders. Plasma concentrations of anterior pituitary hormones (GH, ACTH, TSH, PRL, LH and FSH) were measured before and after simultaneous iv administration of GHRH, CRH, TRH and LHRH. In addition, changes in the plasma levels of GHRH and GH were investigated before and after oral administration of L-dopa. Normal subjects showed appreciable responses to both tests. In five patients with hypothalamic disorders, the response of plasma anterior pituitary hormones varied, but plasma GHRH and GH did not respond to L-dopa. Patients with idiopathic and postpartum hypopituitarism showed low response to 4RHs or none at all, but L-dopa evoked a normal GHRH response in 2 of the 4 cases having no GH response. In the patients with hypopituitarism due to resection of a pituitary tumor, the response of anterior pituitary hormones to 4RHs was low, and L-dopa administration induced a normal GHRH and low GH response in 5 out of the 7 cases. After 4RHs administration, the patients with ACTH deficiency syndrome showed different patterns of impaired ACTH secretion, and isolated, combined or limited ACTH reserve. Seven patients with anorexia nervosa showed exaggerated GH, delayed TSH and FSH, low ACTH and LH, that is, normal PRL response to 4RHs, but no response of plasma GHRH or GH to L-dopa, suggesting the presence of hypothalamic dysfunction. These results indicate that the combination of the 4RHs test and L-dopa test is a simple and useful means for evaluating hypothalamic-pituitary function by measuring the response of plasma GHRH and six anterior pituitary hormones in the patients with endocrine disorders.

Loss of the same alleles of HRAS1 and D11S151 in two independent pancreatic cancers from a patient with multiple endocrine neoplasia type 1

The DNAs from two independent pancreatic cancers (tumors 1 and 2) in a patient with multiple endocrine neoplasia type 1 were analyzed. No amplification or gross rearrangement of 19 protooncogenes was observed. However, Southern blot analysis using polymorphic DNA probes revealed loss of heterozygosity at loci on chromosome 11p in both tumors. In tumor 1, an extensive region including the HRAS1, PTH, CALCA, and D11S151 loci was deleted, while in tumor 2 loss of heterozygosity was limited at the HRAS1 and D11S151 loci. Because loss of heterozygosity at other chromosomal loci in the two tumors was quite rare, loss of genes on 11p might be nonrandom. It is noteworthy that the same allele at the HRAS1 locus and also the same allele at the D11S151 locus were lost in the two independent tumors. These results suggest that loss of genes at the HRAS1 and/or D11S151 loci plays an important role unmasking the remaining sequences probably having a recessive mutation.

Ectopic production of parathyroid hormone by small cell lung cancer in a patient with hypercalcemia

Severe hypercalcemia (serum calcium, 4.37-4.84 nmol/L) was found in a 70-yr-old man who had a small cell carcinoma of the lung with multiple metastases. The plasma immunoreactive PTH concentration was markedly elevated, as measured in three different PTH assays [N-terminal PTH, 4,650 ng/L (normal, 230-630); midregion PTH, 13,850 ng/L (normal, 180-560); C-terminal PTH, 9,900 ng/L (normal, less than 1,300)], but at autopsy the parathyroid glands were histologically normal. The PTH concentration of a liver metastasis was 503.5 ng/g wet wt (normal liver, less than 4.2-5.9), and the PTH in the tumor extract eluted at nearly the same position as synthetic human PTH-(1-84) on gel filtration chromatography. Northern blot analysis revealed PTH mRNA in the tumor as a single band of 0.9 kilobase. These results indicate that the ectopic PTH production by the lung cancer was the cause of hypercalcemia in this patient.

Structure and heterogeneity of the oligosaccharides from the lipopolysaccharides of a pyocin-resistant Neisseria gonorrhoeae

The compositions and partial structures of the oligosaccharides from the lipopolysaccharides (LPS) of a pyocin-resistant Neisseria gonorrhoeae (strain JW31R) have been determined by liquid secondary ion mass spectrometry (LSIMS), tandem mass spectrometry, and methylation analysis. Four major structures were identified with Mr 2123, 2000, 1961, and 1838, as well as seven species of lower abundance of Mr 1758-1272. The largest of the major oligosaccharides (Mr, 2122) consists of 3-deoxymanno-2-ketooctulosonic acid (KDO)-Hep2GalNAcGlcNAcGal4Glc2 (Hep, heptose) and phosphoethanolamine (PEA). The smaller oligosaccharides are truncated versions of this larger oligosaccharide. The oligosaccharides consist of a common triantennary structure containing KDO at the reducing terminus attached to a heptose disaccharide. A hexose (Hex)2-3 branch is attached to the heptose linked directly to KDO and a GalNAc-Hex3, GlcNAc, and PEA are separately attached to the second heptose. These oligosaccharides are the first structures to be determined for a gonococcal LPS and should further our understanding of the structural and antigenic diversity of these glycolipids.

Epitope expression of gonococcal lipooligosaccharide (LOS). Importance of the lipoidal moiety for expression of an epitope that exists in the oligosaccharide moiety of LOS

Antigenic expression of lipooligosaccharide (LOS) of strain F62 of Neisseria gonorrhoeae, was investigated with mouse monoclonal IgM antibody 3F11. F62 LOS was modified in various ways in order to understand structural requirements for expression of the 3F11-defined epitope. When the LOS was partially deacylated by treating it with 50 mM NaOH at 80 degrees C for 20 min or with anhydrous hydrazine at 80 degrees C for 20 min, the binding of 3F11 to those deacylated LOS samples decreased significantly. Removal of phosphate groups by treatment of the LOS with HF (4 days at 4 degrees C) did not affect the antigenicity at all. Neither did reduction of carboxyl groups in the LOS molecule (by activation of carboxyl groups with a carbodiimide followed by treatment with NaBH4) alter epitope expression. On oxidation with NaIO4, the LOS lost its antigenicity completely. The presence of Mg2+ did not change the circular dichroism (CD) behavior of F62 LOS. However, the partially deacylated LOS samples showed significantly different CD patterns in the 190-200 nm region compared with F62 LOS, which suggests conformational changes of F62 LOS due to the loss of fatty acids in the lipoidal moiety. Oligosaccharide (OS) and lipoidal components obtained after hydrolysis of F62 LOS with 1% acetic acid, were not recognized by the antibody. The antigenicity of OS was not retained by non-stereospecific acylation of OS with decanoyl chloride. We conclude the following: (1) 3F11-defined epitope exists in the OS moiety of F62 LOS; however, for it to be expressed, the carbohydrate moiety must be in a certain conformation that is defined by an overall structure of the LOS molecule. This structure is significantly influenced by some of the fatty acids in the lipoidal moiety of the LOS molecule; (2) the presence of phosphate or 3-deoxy-manno-2-octulosonic acid (dOclA) is not essential for expression of the 3F11-defined epitope; (3) the presence of divalent cations does not affect epitope expression.

2D NMR analysis of group B capsular polysaccharide of N. meningitidis: complete assignment of 1H-NMR spectrum of B polysaccharide of strain 6275

Group B capsular polysaccharide of N. meningitidis was analyzed by 2D NMR spectroscopy. The 1H-NMR spectrum of the polymer was completely assigned by 2D homonuclear (COSY and HOHAHA) and heteronuclear (1H, 13C) NMR experiments.

Lipooligosaccharides: the principal glycolipids of the neisserial outer membrane

The outer-membrane glycolipids of bacteria that colonize mucosal surfaces that are not routinely bathed by bile acids often lack the long, hydrophilic and neutral polysaccharides that protect the lipid membranes of enteric bacteria from dispersal. The glycolipid from these organisms is properly termed a lipooligosaccharide. A Neisseria strain makes from two to six lipooligosaccharide molecules that range in Mr from 3,150 to 7,100. Different species of Neisseria commonly make lipooligosaccharides of identical Mr and epitope content. Differences in oligosaccharides account for most of the observed physical heterogeneity. Oligosaccharides consist of (1) partially conserved and highly substituted basal oligosaccharides that branch at heptose residues; (2) a linear segment consisting of (hexose)n residues that determines the length of the oligosaccharide; and (3) terminal sequences that are similar to those of glycosphingolipids. Epitope expression is linked to physical heterogeneity and is modified by the molecular environment of the outer membrane. Serotype epitopes are present only on lipooligosaccharides of a certain Mr. Certain lipooligosaccharides regulate complement activation onto the bacterial surface and, hence, immune lysis.

Secretion of growth hormone-releasing hormone in patients with idiopathic pituitary dwarfism and acromegaly

The plasma levels of immunoreactive-GHRH in patients with idiopathic pituitary dwarfism and acromegaly were studied in the basal state and during various tests by a sensitive and specific RIA. The fasting plasma GHRH level in 22 patients with idiopathic pituitary dwarfism was 6.3 +/- 2.3 ng/l (mean +/- SD), which was significantly lower than that in normal children (9.8 +/- 2.8 ng/l, N = 21), and eight of them had undetectable concentrations (less than 4.0 ng/l). Little or no response of plasma GHRH to oral administration of L-dopa was observed in 7 of 10 pituitary dwarfs, and 3 of the 7 patients showed a response of plasma GH to iv administration of GHRH (1 microgram/kg). These findings suggest that one of the causes of idiopathic pituitary dwarfism is insufficient GHRH release from the hypothalamus. The fasting plasma GHRH level in 14 patients with acromegaly and one patient with gigantism was 8.0 +/- 3.9 ng/l, which was slightly lower than that in normal adults (10.4 +/- 4.1 ng/l, N = 72). One acromegalic patient with multiple endocrine neoplasia type I had a high level of plasma GHRH (270 ng/l) with no change in response to L-dopa and TRH test. In 3 untreated patients with acromegaly L-dopa did not induce any response of plasma GHRH in spite of inconsistent GH release, and in 4 patients with acromegaly, TRH evoked no response of plasma GHRH in spite of a marked GH release, suggesting that the GH responses are not mediated by hypothalamic GHRH.(ABSTRACT TRUNCATED AT 250 WORDS)

Ectopic growth hormone-releasing hormone (GHRH) syndrome in a case with multiple endocrine neoplasia type I

A 36-yr-old man with multiple endocrine neoplasia (MEN) type I had an ectopic growth hormone-releasing hormone (GHRH) syndrome due to a GHRH-secreting pancreatic tumor. The immunoreactive (IR)-GHRH concentration in his plasma ranged from 161 to 400 pg/ml (299 +/- 61 pg/ml, mean +/- SD; normal, 10.4 +/- 4.1 pg/ml), and a significant correlation was found between his plasma IR-GHRH and GH (r = 0.622, p less than 0.02). After removal of the pancreatic tumor, the high plasma GH concentration returned to nearly the normal range (42.2 +/- 31.3 to 9.6 +/- 3.8 ng/ml). These changes paralleled the normalization of his plasma IR-GHRH (16.1 +/- 3.8 pg/ml) and some of his symptoms related to acromegaly improved. However, plasma GH (7.7 +/- 1.3 ng/ml) and IGF-I (591 +/- 22 ng/ml) concentrations were high at 12 months after surgery, suggesting adenomatous changes in the pituitary somatotrophs. Before surgery, exogenous GHRH induced a marked increase in plasma GH, and somatostatin and its agonist (SMS201-995) completely suppressed GH secretion, but not IR-GHRH release. No pulsatile secretion of either IR-GHRH or GH was observed during sleep. An apparent increase in the plasma GH concentration was observed in response to administration of TRH, glucose, arginine or insulin, while plasma IR-GHRH did not show any fluctuation. However, these responses of plasma GH were reduced or no longer observed one month and one year after surgery. These results indicate that 1) a moderate increase in circulating GHRH due to ectopic secretion from a pancreatic tumor stimulated GH secretion resulting in acromegaly, and evoked GH responses to various provocative tests indistinguishable from those in patients with classical acromegaly, and 2) the ectopic secretion of GHRH may play an etiological role in the pituitary lesion of this patient with MEN type I.

Growth hormone-releasing hormone (GHRH)-secreting pancreatic tumor in a patient with multiple endocrine neoplasia type I

A growth hormone-releasing hormone (GHRH)-secreting pancreatic tumor in a 36-year-old man, who had typical, familial, multiple endocrine neoplasia (MEN) type I with hyperparathyroidism and acromegaly, is described. The resected tumor, weighing 30 g, showed unusual histological features characterized by a meningioma-like arrangement of crescent-shaped cells and contained many cells that reacted with C-terminal specific antibody to GHRH-44 and a few somatostatin-immunoreactive (IR) and calcitonin-IR cells, but no GH-IR cells. A high concentration of IR-GHRH (9.8-13.2 micrograms/g wet weight tissue) with the full molecular size of GHRH-44 was detected in a tumor extract. Electron immunocytochemical study by the protein A-gold method revealed GHRH-IR granules with a mean diameter of 147 nm. After removal of the tumor, the plasma IR-GHRH level became normal (decreasing from 299 to 16.1 pg/ml) and the plasma IR-GH level also decreased, but still remained slightly high (decreasing from 42.4 to 9.6 ng/ml), suggesting the presence of an adenomatous lesion in the hypophysis.

[Effect of oral administration of L-dopa on the plasma levels of growth hormone-releasing hormone (GHRH) in normal subjects and patients with various endocrine and metabolic diseases]

The responses of plasma growth hormone-releasing hormone (GHRH) and growth hormone (GH) to oral administration of L-dopa were studied in normal subjects and patients with various endocrine and metabolic diseases to clarify the pathophysiological role of the GHRH-GH axis. In normal subjects, the plasma GHRH concentration was increased from the basal value of 9.8 +/- 1.4 pg/ml (mean +/- SE) to 34.8 +/- 3.1 pg/ml at 30 approximately 90 min after oral administration of 500 mg L-dopa, followed by a rise of GH release (plasma GH level from less than 1 ng/ml to 21.7 +/- 4.7 ng/ml) in most cases, indicating that L-dopa stimulates GH secretion via hypothalamic GHRH. On L-dopa administration, no apparent increases in both plasma GHRH and GH concentrations were observed in patients with hypothalamic hypopituitarism, whereas GHRH administration induced almost normal GH response. In patients with acromegaly, the plasma levels of GHRH remained stationary after the L-dopa administration and did not correlate with plasma GH levels. In subjects with simple obesity, the responses of plasma GHRH (peak 13.2 +/- 1.2 pg/ml) and GH (peak 4.3 +/- 1.7 ng/ml) to L-dopa were significantly lower than those in normal subjects (p less than 0.01). In patients with primary hypothyroidism, peak levels of plasma GHRH (12.6 +/- 1.3 pg/ml) and GH (2.4 +/- 0.6 ng/ml) were significantly lower than those in normal subjects (p less than 0.01). In patients with non-insulin dependent diabetes mellitus (NIDDM), the responses of GHRH and GH were divided into 2 groups; in the responder the peak values of GHRH and GH were 19.4 +/- 8.6 pg/ml and 12.2 +/- 1.4 ng/ml and in the low or non responder 14.7 +/- 1.5 pg/ml and 2.0 +/- 0.6 ng/ml, respectively. Between both groups, there was a significant difference in the values of fasting blood sugar and HbA1 and mean suffering period. These findings suggest that GH secretion evoked by the L-dopa administration is induced by GHRH released from the hypothalamus, and impairment of GH secretion associated with simple obesity, primary hypothyroidism, or NIDDM may be in part attributed to insufficiency of GHRH release from the hypothalamus, and indicate that L-dopa test is clinically useful for evaluating the ability of intrinsic GHRH release in such diseased states.

Physical heterogeneity of neisserial lipooligosaccharides reflects oligosaccharides that differ in apparent molecular weight, chemical composition, and antigenic expression

We studied the oligosaccharides (OS) of outer membrane lipooligosaccharides (LOS) of Neisseria gonorrhoeae and Neisseria meningitidis. OS from the LOS of an individual neisserial strain always eluted from Sephadex G-50S as multiple peaks; the polyacrylamide gel elution profiles were nearly identical to the polyacrylamide gel electrophoresis profiles of the sodium dodecyl sulfate-disaggregated native LOS from which the OS were derived. Neisserial OS coeluted with Dex14 to Dex27 dextran oligomers (Mr, 2,210 to 4,320). Monosaccharide composition varied among the several OS released from the LOS of a single strain. The two OS of a gonococcal strain sensitive to normal human serum (NHS) bacteriolysis (sers) varied in their ability to inhibit the binding of NHS immunoglobulin M to their parental LOS. The OS that was rich in hexosamines inhibited NHS immune lysis of its parent strain; the OS that was poor in hexosamines did not. We conclude that structural differences in their OS account for the Mr heterogeneity of the LOS of a strain.

Production and secretion of immunoreactive growth hormone-releasing factor by pheochromocytomas

The production and secretion of immunoreactive growth hormone-releasing factor (IR-GRF) by pheochromocytomas were examined immunohistochemically and immunochemically. GRF-immunoreactive (GRF-IR) cells were found, although sparsely, in 2 of 13 tumors (Cases 1 and 2), while somatostatin (SRIF)-IR cells and vasoactive intestinal peptide (VIP)-IR cells were found in nine and five tumors, respectively. Concentrations of tissue IR-GRF of 29.8 and 17.2 ng/g wet weight tissue, respectively, were found in two (Cases 1 and 2) of three tumors examined. These three tumors also contained IR-SRIF at 19.5-105.5 ng/g wet weight tissue and IR-VIP at 13.6-24.8 ng/g wet weight tissue. An increased plasma IR-GRF concentration (30.0 pg/ml) was found in a blood sample taken from the inferior vena cava near the adrenal tumor in Case 1. This is the first report that some pheochromocytomas produce GRF and secrete it into the blood circulation.

Immunoreactive somatostatin and calcitonin in pulmonary neuroendocrine tumor

A well-differentiated neuroendocrine carcinoma of the lung that secreted immunoreactive somatostatin (IR-SRIF) and IR-calcitonin (CT) in a 72-year-old women is described. The plasma concentrations of IR-SRIF (57.5 pg/ml) and IR-CT (340 pg/ml) before operation were significantly higher than the respective normal ranges. After resection of the tumor, the plasma CT level (105 pg/ml) decreased to within the normal range, and the SRIF level (32.7 pg/ml) also decreased, but was still abnormally higher, which suggested the presence of an unidentified remnant of the tumor. Abnormal accumulation of technetium 99m (99mTc) in the lumbar vertebrae was found 6 months after the operation, which indicated a metastatic tumor. The tissue concentrations of IR-SRIF and IR-CT were 103 and 94 ng/g wet weight, respectively, and SRIF-IR tumor cells and CT-IR tumor cells were demonstrated immunohistochemically. On gel-filtration chromatography of the tumor tissue, two peaks of SRIF immunoreactivity were eluted in the positions of synthetic SRIF-28 and SRIF-14, respectively. Conversion of SRIF-28 to SRIF-14 was suggested from results on changes in the two IR-SRIF components during incubation with a crude enzyme preparation extracted from the tumor tissue.

Radioimmunoassay of an analog of luteinizing hormone-releasing hormone, [D-Ser(tBu)]6des-Gly-NH2(10) ethylamide (Buserelin)

A sensitive and specific radioimmunoassay is described for plasma and urinary levels of [D-Ser(tBu)]6des-Gly-NH2(10) ethylamide (buserelin). No appreciable cross-reaction (less than 0.05%) was observed with LH-RH and its analogs other than buserelin fragments (1.6-45%). The sensitivity was 3 pg per tube. At buserelin concentrations of 125, 250 and 500 pg/ml, the intra- and inter-assay coefficients of variation were 7.9, 10.0 and 10.0%, and 19.0, 7.8 and 6.8% respectively. Recovery of buserelin added to plasma was quantitative (62.5 pg/ml, 101.6%; 125 pg/ml, 76.8% and 250 pg/ml, 63.4%). A dose of 5 micrograms buserelin injected subcutaneously into 5 normal male adults, reached a peak plasma level in 45 min (mean value 119.3 +/- 47.3 pg/ml) and remained detectable for at least 4 h. The half disappearance time was 118.8 +/- 26.0 min. Between 9 and 16% of the administered dose was excreted in the urine within 24 h. Buserelin could also be detected in the plasma after intranasal administration of doses of 150, 300 and 450 micrograms. There was a significant difference in the area under the curve (AUC) for plasma levels after subcutaneous injection of 5 micrograms and intranasal administration of 150 micrograms, but not between the AUC values after the three intranasal doses. These results indicate that this method for radioimmunoassay of buserelin is suitable for analyzing the pharmacokinetics and bioavailability of buserelin in man.

Secondary structure and phylogeny of Staphylococcus and Micrococcus 5S rRNAs

Nucleotide sequences of 5S rRNAs from four bacteria, Staphylococcus aureus Smith (diffuse), Staphylococcus epidermidis ATCC 14990, Micrococcus luteus ATCC 9341 and Micrococcus luteus ATCC 4698, were determined. The secondary structural models of S. aureus and S. epidermidis sequences showed characteristics of the gram-positive bacterial 5S rRNA (116-N type [H. Hori and S. Osawa, Proc. Natl. Acad. Sci. U.S.A. 76:381-385, 1979]). Those of M. luteus ATCC 9341 and M. luteus ATCC 4698 together with that of Streptomyces griseus (A. Simoncsits, Nucleic Acids Res. 8:4111-4124, 1980) showed intermediary characteristics between the gram-positive and gram-negative (120-N type [H. Hori and S. Osawa, 1979]) 5S rRNAs. This and previous studies revealed that there exist at least three major groups of eubacteria having distinct 5S rRNA and belonging to different stems in the 5S rRNA phylogenic tree.

Synthesis of 1-, 6- and 1,6-derivatives of methyl D-fructofuranosides

A variety of derivatives of methyl α- and β-D-fructofuranosides modified at C1 or C6, or at C1 and C6, have been prepared in which the hydroxyl group(s) has been replaced by azido, amino, chloro, bromo, hydrogen and thiol acetate functions. These compounds were made by displacements on methyl 1,6-di-O-p-toluenesulfonyl-D-fructofuranosides, or on 2,3-O-isopropylidene-l,6-di-O-p- toluenesulfonyl-β-D-fructofuranose and subsequent glycosidation. A number of indirect methods of preparation of methyl D-fructofuranosides, mostly based on 1,3,4,6-tetra-O-benzoyl-D-fructofuranose have been investigated.

An analysis of the 1H N.M.R. spectra and conformation of fructofuranoside derivatives in solution

The 1H n.m.r. spectra of a number of D-fructofuranosides and related compounds, including 3,4-oxiran derivatives, are reported. The conformation of D-fructofuranosides in solution is discussed.

Isolation of tissue plasminogen activator from skin lesions with allergic vasculitis

A tissue plasminogen activator was extracted from skin lesions with allergic vasculitis and purified by successive column chromatography on Sephadex G-200, DEAE-cellulose, Hydroxyaptite-cellulose and polyacrylamide gel electrophoresis. By these procedures, 160 micrograms of enzyme with a specific activity of 843.8 international units/mg protein was obtained from 5 g of original skin. The purified material was homogeneous as ascertained by sodium dodecyl sulfate polyacrylamide gel electrophoresis and had an apparent molecular weight of 110,000 as measured by gel filtration on Sephadex G-200. Its identity with human urokinase was investigated and was found to possess the same plasminogen activator activity as that of urokinase. It had high amindolytic activity, but only slight N-alpha-acetyl-glycyl-L-lysine methyl ester esterolytic activity. This tissue plasminogen activator was confirmed to be immunologically identical to human urokinase.

Synthesis of some derivatives of 2,5-Anhydro-D-mannitol

The synthesis of 2,5:3,4-dianhydro-D-allitol and of a variety of derivatives (sulfonyloxy, deoxy, azido, iodo, etc.) of 2,5-anhydro-D-mannitol is described.