Indomethacin promotes germinal matrix microvessel maturation in the newborn beagle pup

BACKGROUND AND PURPOSE

Although indomethacin has been demonstrated to prevent germinal matrix and intraventricular hemorrhage in clinical and animal studies, the mechanism of action of this agent to prevent hemorrhage remains unclear. Previous studies have demonstrated both that the microvessels in the germinal matrix of newborn beagle pups undergo basement membrane maturation during the first 4 postnatal days and that indomethacin may promote laminin deposition in tumor cell culture systems.

METHODS

We employed the newborn beagle pup model to test the hypothesis that indomethacin may stimulate laminin deposition in germinal matrix microvessels. Newborn pups were randomized to receive either 0.1 mg/kg/dose i.p. indomethacin or an equal volume of saline diluent. Pups received doses of study medication once a day for 1, 2, or 3 days and were studied on postnatal days 1, 2, 3, or 4. Pups were anesthetized and systemically perfused with buffered formalin; the brains were removed and prepared for immunohistochemical study.

RESULTS

Sections stained with Bandeiraea lectin demonstrated that there was no difference in germinal matrix vessel density among the postnatal ages studied; similarly, there were no differences in vessel density between saline- and indomethacin-treated animals at any postnatal age. Quantification of germinal matrix stained intensity by confocal microscopy demonstrated significant increases in indomethacin-treated pups for both laminin staining at postnatal days 2 (p = 0.05) and 3 (p = 0.0009) and type V collagen staining at postnatal day 2 (p = 0.011). Although staining for beta 1 integrins increased across postnatal ages, there were no differences between saline- and indomethacin-treated animals.

CONCLUSIONS

These data suggest that indomethacin may stimulate basement membrane deposition in the germinal matrix microvessels of newborn beagle pups to prevent germinal matrix and/or intraventricular hemorrhage.

Characterization of N-linked oligosaccharides by electrospray and tandem mass spectrometry

Electrospray and tandem mass spectrometry are used to characterize underivatized oligosaccharides that have been digested from asparagine side chains of glycoproteins. Oligosaccharides that contain sialic acids were detected with the best sensitivity in the negative-ion detection mode whereas those that do not contain sialic acid were detected with the best sensitivity in the positive-ion detection mode. The positive-ion abundances of oligosaccharides were greatly enhanced in electrospray mass spectra by adding 10 mM sodium acetate or ammonium acetate to the sample solvent. Tandem mass spectrometry was used to determine primary structural features of the oligosaccharides. Methodology that has been developed on branched high-mannose, hybrid, and complex carbohydrate standards was applied to a mixture of oligosaccharides that were digested with N-glycanase from the glycoprotein, ovalbumin. The composition and relative abundances of individual oligosaccharides obtained from the electrospray mass spectrum compare favorably to those obtained by anion-exchange chromatography/pulsed amperometric detection and by gel permeation chromatography of the oligosaccharides after radiolabelling the reducing end of the carbohydrates. The oligosaccharide content of ovalbumin was independently determined from the heterogeneity observed in the electrospray mass spectrum of the intact 44-kDa glycoprotein. Comparison of the oligosaccharide compositions determined before and after enzymatic digestion shows a selective digestion of high-mannose and low molecular weight oligosaccharides by N-glycanase.

Kappa 3 opiate receptor binding in the mouse and rat

Previous work examining the binding of [3H]naloxone benzoylhydrazone (NalBzoH) in calf brain has identified a novel binding site, kappa 3. In mice and rats NalBzoH elicits an analgesic response which can clearly be differentiated from classical mu, delta or kappa 1 mechanisms and which is pharmacologically consistent with a kappa 3 receptor mechanism of action. In the current studies we demonstrate the presence of kappa 3 sites in both mouse and rat brains. The selectivity of the kappa 3 sites for opioids clearly discriminated it from traditional mu, kappa 1, kappa 2 or delta receptors. In the rat, the density of kappa 3 sites increased 2.5-fold from age 2 days to 21 days, after which it remained relatively stable. Among a number of brain regions in the rat, the density of kappa 3 sites varied dramatically. Highest levels were present in the hypothalamus, thalamus, striatum and midbrain with very low levels in the cerebellum. Intermediate levels were present in cortex, brain stem and spinal cord. Together, these studies support the presence of kappa 3 receptors in both mouse and rat brain which are very similar to those previously reported in calf brain.

[Steroid alkaloids from stems and leaves of Fritillaria ussuriensis Maxim]

Three crystalline chemical components were isolated from the stems and leaves of Fritillaria ussuriensis by column chromatographic technique. On the basis of the IR, MS and 1HNMR spectra, the structure has been identified as pingbeimine B, pingbeimine C and pingbeininoside.

cAMP and cAMP-dependent protein kinase regulate the human heat shock protein 70 gene promoter activity

The theme of this study is an evaluation of the involvement of cAMP and cAMP-dependent protein kinase (PKA) in the regulation of the human heat shock protein (hsp) 70 gene promoter. Expression of a highly specific protein inhibitor of PKA (pRSVPKI) inhibited the basal as well as heat- and cadmium-induced expression of the cotransfected pHBCAT, a human hsp 70 promoter-driven reporter gene; this inhibition was dependent on the amount of pRSVPKI used. The effect of an expression vector of the RI regulatory subunit of PKA, pMTREV, was similar to that of pRSVPKI; pMTREV inhibited both the basal as well as the heat-induced expression of pHBCAT. The specificity of effects of these expression vectors was demonstrated by the lack of effect of a mutant PKI gene and by the unaffected expression of a reference gene (pRSV beta gal) under these conditions. Analysis of the effects of dibutyryl cAMP (1 mM), forskolin (10 microM), and 8-Br-cAMP (1 mM) on the transient expression of pHBCAT showed that these cAMP-elevating agents stimulated the hsp 70 promoter activity, whereas cAMP (1 mM) was without effect. Chloramphenicol acetyltransferase gene constructs with truncated or mutated hsp 70 promoter were used to define the cis-acting DNA element(s) that confer this cAMP stimulation; the heat induced (42 degrees C) expression was used as a control. Mutation of the adenovirus transcription factor element (pLSN-40/-26) greatly reduced the basal level of expression; forskolin had little or no effect on this adenovirus transcription factor-minus promoter, although the promoter activity was very heat inducible. The absence of a functional heat shock consensus element (HSE) in the construct pLSPNWT rendered the promoter heat insensitive; this construct was forskolin responsive although the magnitude of this stimulation was reduced when compared with that of a control construct with HSE. These results were corroborated by studies using consensus sequence of ATF (ATFE) and HSE as competitors to titrate our cellular factors that may interact with these elements. We showed that cotransfection with ATFE and HSE depressed the basal (37 degrees C) expression of pHBCAT by 25 and 60%, respectively. The heat-induced expression of pHBCAT was not significantly affected by the cotransfection of ATFE and was reduced by 60% when HSE was cotransfected. ATFE and HSE reduced the forskolin-induced pHBCAT expression by 70 and 40%, respectively. The implications of these findings as they relate to the action of cAMP and cAMP-dependent protein kinase in the control of heat shock gene expression are discussed.

The hematopoietic growth factor KL is encoded by the Sl locus and is the ligand of the c-kit receptor, the gene product of the W locus

Mutations at the steel locus (Sl) of the mouse affect the same cellular targets as mutations at the white spotting locus (W), which is allelic with the c-kit proto-oncogene. We show that KL, a hematopoietic growth factor obtained from conditioned medium of BALB/c 3T3 fibroblasts that stimulates the proliferation of mast cells and early erythroid progenitors, specifically binds to the c-kit receptor. The predicted amino acid sequence of isolated KL-specific cDNA clones suggests that KL is synthesized as an integral transmembrane protein. Linkage analysis maps the KL gene to the Sl locus on mouse chromosome 10, and KL sequences are deleted in the genome of the Sl mouse. These results indicate that the Sl locus encodes the ligand of the c-kit receptor, KL.

[Chemical studies on the constituents of Daphne koreane Nakai]

In this paper three compounds isolated from Daphne koreane are described. Their structures have been identified as beta-sitosterol, naringenin and 7,8-dimethoxycoumarin on the basis of spectral data and chemical reactions.

[Alkaloid constituents of Fritillaria pallidiflora Schrenk]

Three steroid alkaloids were isolated from the bulb of Fritillaria pallidiflora. On the basis of spectroscopic analysis and physico-chemical constants they were identified as imperialine, imperialine-beta-D-glucoside and peimissine.

A rare etiology for pulmonary embolism: basilic vein thrombosis

A 61-year-old white male with recurrent thrombophlebitis developed a painful left arm. He was initially diagnosed with superficial thrombophlebitis and treated conservatively for several days without improvement. He subsequently developed right-sided pulmonary embolism. Hypercoagulability was not present, and venography confirmed the left basilic vein as the sole thrombogenic source. Twelve to twenty percent of documented pulmonary emboli arise from deep veins of the upper extremity. To our knowledge, only one case of basilic vein thrombosis causing pulmonary embolism exists in the literature. Clinical vigilance to this uncommon entity may reduce attendant morbidity and mortality.

The impact of dedicated physician staffing on patient flow and quality assurance parameters in an Air Force emergency department

A retrospective audit of 17,028 emergency charts at USAF Medical Center, Scott was performed over two time periods to compare patient waiting times and selected quality assurance parameters with two methods of physician staffing. Phase 1 consisted of 4 months when the Emergency Department (ED) was manned with five physicians assigned only to that department. Non-departmental physicians supplemented the full-time staff. Phase 2 was the corresponding 4 months the following year when the ED was staffed with six emergency physicians, and non-emergency physician coverage was minimal. The difference in daily census between the two periods of time was not statistically significant. The time required to be seen by a physician decreased from an average of 25.6 minutes per patient in phase 1 to 13.7 minutes per patient in phase 2. Time to disposition also decreased from 71.9 minutes per patient in phase 1 to 59.5 minutes per patient in phase 2. In the second phase the number of "positive" x-ray findings increased, while the number of incomplete charts and patients who left without being seen by a physician diminished.

Hematometra presenting as acute appendicitis: a case report

A case of intrauterine blood passing into the abdominal cavity and resulting in a clinical picture similar to acute appendicitis is presented. To our knowledge, hematometra presenting in this manner has not been reported in the medical literature. Some disease processes which more commonly mimic acute appendicitis include nonspecific mesenteric adenitis, gynecologic disorders, diverticulitis, and urinary tract infection. Unusual diseases presenting in this manner include splenic torsion, infarcted omentum, ileocecal tuberculosis, and duodenal hematoma.

Mechanism of the Body-Centered Cubic—Hexagonal Close-Packed Phase Transition in Iron

The transition from body-centered cubic to hexagonal close-packed phase in iron has been studied in a diamond anvil cell with synchrotron radiation. The hexagonal close-packed phase, when it first appears, has a ratio of lattice parameters that is significantly larger than normal. This is attributed to a displacive mechanism that causes a distortion of the hexagonal close-packed structure in a body-centered cubic matrix. The hexagonal close-packed phase adjacent to a boundary with the body-centered cubic phase is stretched in the c direction and compressed in the a direction when it first forms.

Role of envelope glycoprotein carbohydrate in human immunodeficiency virus (HIV) infectivity and virus-induced cell fusion

Human immunodeficiency virus (HIV) envelope glycoprotein interactions with cell surface CD4 are involved in both virion infectivity and virally mediated cell fusion. D-mannose-specific lectins such as Con A specifically blocked virion infectivity and cell fusion. Studies with a recombinant vaccinia virus containing the HIV envelope gene demonstrated that Con A-mediated inhibition of HIV-induced fusion involved lectin binding to the viral envelope glycoprotein. These results indicate the importance of envelope glycosylation in the pathobiology of HIV infection, and suggest potential mechanisms for interfering with HIV infectivity and cytopathology.

Persistence of both human cytomegalovirus and Epstein-Barr virus genomes in two human lymphoblastoid cell lines

By DNA-DNA reassociation kinetic analysis, less than one genome equivalent per cell of human CMV-DNA was found in two lymphoblastoid cell lines, one derived from the peripheral blood of a congenitally infected male infant at the age of 21 months (D4 cell line), the other obtained by co-cultivation of lethally X-irradiated cells from the 9-month lymphoblastoid cell line previously described by Joncas et al. (1975) with cord blood leukocytes of a female newborn (M1 cell line). Human CMV antigens could not be detected and virus could not be rescued from these cells by co-cultivation with fully permissive human fibroblasts. It may be that the CMV-DNA is defective. Epstein-Barr virus DNA as well as EBNA and EBV-EA antigens were present in these cell lines. Both lines express surface markers characteristic of thymus-independent, B lymphocytes. The CMV-DNA of the CMV-DU strain, isolated from this infant's urine five times successively from the age of 1 day to 30 months, appears to be closely related to the DNA of the AD-169 strain by reciprocal hybridization and by electrophoretic pattern analysis of the restriction enzyme cleavage products. Experimental attempts to transform cord blood leukocytes with this urine strain of CMV before or after u.v. irradiation have so far failed.

Predicting the Most Favored Path and the Overall Rate of Multistep: 2-Norbornyl Cation Rearrangements. The Assignment of a Trial Activation Energy for Each Unique Step

Observable 2-norbornyl cations undergo at least five different rearrangement reactions, all of which are known from previous work on this system. In this paper, these rearrangement categories have been subdivided to reflect secondary–tertiary energy and rate differences and a trial set of activation free energies ΔG≠ is derived for each subdivided step. The most important of these parameters is the energy difference between secondary and tertiary (methyl) systems which was estimated as 5.5 kcal/mol. These parameters allow one, for the first time, to make a rational assessment of the overall reaction course of multistep rearrangement reactions in this system, for example, those observed in a number of bicyclo[2.2.1]heptyl(norbornyl) terpene systems.

The Observable Thirtyfold Degenerate Camphenehydro Cation. A Stereospecific exo-3,2-Methyl Shift and endo-6,2(exo 6,1)-Hydride Shift

The observable camphenehydro cation 2 has been prepared and is shown to undergo two degenerate rearrangements, both well known in an indirect sense from many studies on the racemization of camphene. The results from both methods are compared and some advantages of the direct method are given; in particular it is shown that the 3,2-methyl shift is highly stereospecific. An eventual irreversible rearrangement of 2 is observed and the ion products characterized. A computer is used to systematically investigate the shortest paths from reactant to product ions.