A cell line derived from normal, adult rat liver has been established; the cells are similar to hepatocytes, as shown by electron microscopy. The addition of dexamethasone to the culture medium induced a three- to sixfold increase in the specific activity of tyrosine alpha-ketoglutarate transaminase; this increase was inhibited by the simultaneous addition of cycloheximide or actinomycin D. The latter, when added to cells given prior treatment with dexamethasone, further enhanced the transaminase activity. Contact-inhibited cells showed a lower response to dexamethasone than exponentially growing cells.

Animals↗

PubMedDate not supplied

Cerebrospinal fluid neopterin and beta 2-microglobulin levels in neurologically asymptomatic HIV-infected patients before and after initiation of zidovudine treatment.

The effect of zidovudine on beta 2-microglobulin and neopterin in the cerebrospinal fluid (CSF) was studied in ten HIV-seropositive neurologically healthy individuals. CSF concentrations of neopterin decreased by 53% (from 20.3 to 9.5 nmol/l, p < 0.01) and beta 2-microglobulin by 36% (from 2.8 to 1.8 mg/l, p < 0.01) four to eight months after initiation of therapy.

Biopterins↗

PubMedDate not supplied

Separation of cerebrospinal fluid-enriched proteins. A methodological study, Part 2.

Beta-trace protein, beta2-microglobulin and prealbumin were identified in a cerebrospinal fluid fraction containing proteins enriched in CSF-characteristic proteins obtained through affinity chromatography. The prealbumin amount was somewhat higher among CSF-enriched proteins from ventricular CSF than in the same fraction from lumbar CSF. Otherwise no variations in the CSF-enriched protein pattern were found in a ventriculo-spinal CSF-gradient analysed with isoelectric focusing. Affinity chromatography was done using insolubilized antisera against human serum proteins or against human cerebrum. Soluble brain proteins were analysed similarly and compared to the CSF-enriched protein pattern.

Adult↗

PubMedDate not supplied

Isolation and characterization of a variant form of vasoactive intestinal polypeptide.

A variant form of the vasoactive intestinal polypeptide (VIP) has been isolated. It was found to consist of a molecule which instead of the C-terminal asparagine amide of VIP has a C-terminal extension of Gly-Lys-Arg. This VIP variant displaces VIP in a VIP receptor assay, reacts with N-terminally-directed antisera in a VIP radioimmunoassay and possesses VIP-like bioactivity in an assay measuring pancreatic juice secretion in the cat.

Amino Acids↗

PubMedDate not supplied

Synthesis of glycoconjugates by covalent coupling of O-glycopyranosyl-N-hydroxysuccinimide derivatives of lactose to proteins and lipids and polymerization of their parent acryloyl derivatives into acrylamide polymers.

Glycosides of N-hydroxysuccinimide have been synthesized and the succinimide moieties have been opened by amines to give glycolipids or spacer-glycosides. The latter have been coupled to proteins and, after acryloylation, copolymerized into acrylamide polymers. A 13C-NMR study of the stability of the anomeric O-N-C(O) linkage showed the linkage to be stable under conditions used in most biological experiments.

Acrylic Resins↗

PubMedDate not supplied

Flock-feeding on fish schools increases individual success in gulls.

Flock-foraging and the role of white plumage in gulls and other seabirds have been the subject of much debate. At first sight it seems that competition within the flock would render flock formation against the interest of the bird who finds the fish school, as the fish must then be shared with birds joining the flock. However, it is also possible that flock formation is neutral or even beneficial to the individual members, including the bird that found the fish (the 'first finder'). Here we show that the fishing success of individual black-headed gulls, Larus ridibundus, increases with flock size up to at least eight birds. Part of the reason is that the fish school is more vulnerable when attacked by several gulls. The first gull to reach a fish school therefore benefits from being joined by others, and conspicuous white upper parts in gulls may act as a means of attracting other gulls to the flock and hence improving hunting success.

Animals↗

PubMedDate not supplied

Methodological studies of multiple reference genes as endogenous controls in vascular gene expression studies.

Detection and quantification of differentially expressed genes requires valid and reliable references to control for error variability introduced by preparatory procedures or efficiency of reverse transcription and polymerase chain reaction (PCR) amplification conditions. So-called housekeeping genes are frequently used as endogenous standards, based on the assumption that they are constitutively expressed and independent of experimental conditions. However, if the influence of experimental stimuli is to be analyzed, it cannot a priori be assumed that their expression is unaffected by stimulation. In the present study, the authors studied the expression of different housekeeping genes in the vascular endothelium of intact conduit vessels perfused in a unique biomechanical perfusion model. Ten control gene candidates were investigated by microarray expression analysis. Further, five of these genes were systematically analyzed by real-time reverse transcriptase (RT)-PCR gene quantification and their suitability as reference genes were evaluated. On the basis of these findings, the authors suggest criteria for evaluation of endogenous control genes in vascular perfusion studies.

Biomedical Research↗

PubMedDate not supplied

Hormonal regulation of cultured rabbit endometrial cells.

A technique for culturing primary explants of rabbit endometrial cells in chemically defined medium has been developed. Diethylstilbestrol and natural estrogens were found to increase the rate of DNA initiation while progesterone had the opposite effect. Ultrastructural studies revealed that with estrogens, the cultures had the appearance of rapidly dividing cells having large euchromatic nuclei and prominent nucleoli, with aboundant free ribosomes in the cytoplasm. On the other hand, progesterone induced the formation of large multinucleated cells and also converted the cells to a more secretory type. When the cultures appear secretory, a protein called blastokinin (uteroglobin) is believed secreted. We have found that cultured cells synthesize blastokinin and progesterone is necessary for its continuous synthesis. The cultures were found to have receptors for the ovarian hormones and these receptors exhibited saturation kinetics. The dissociation constants for the receptors were also determined. A hypothetical model for the hormonal regulation of cell proliferation and differentiation is proposed.

Animals↗

PubMedDate not supplied

Ultrasonography revealing the accumulation of rete testis fluid in bull testicles.

Ultrasonography was used for diagnosing accumulation of rete testis fluid in live bulls. When 447 bulls of Ayrshire breed selected for artificial insemination were studied by ultrasonography, eleven were detected in which the ultrasonograms visualized accumulation of rete testis fluid in the testicles. In 7 bulls the accumulation (spermiostasis) was bilateral and in 4 unilateral. In only four out of 18 testicles, macroscopically epididymal cysts were seen after slaughter. At the age of 16 months four bulls with bilateral spermiostasis were azoospermic. When studied by ultrasonography, the rete testis of normal testicles was echogenic and narrow but in affected testicles anechogenic and wide. Nine of the affected bulls were sons of three fathers. We suggest that spermiostasis is hereditary in Ayrshire bulls and, as in the goat, is progressive by nature.

Animals↗

PubMedDate not supplied

Probable spermatozoal diploidy in the semen of a golden retriever.

The semen of a 3-year-old golden retriever was examined for breeding purposes. When the morphology of the spermatozoa was analysed for the first time, 37% were observed to have giant heads. In most of the giant heads, a diadem defect was also found. The dog was successfully used for breeding. On re-examination, the percentage of giant heads was found to be greater than before. The right testicle exhibited tissue softening. To determine the reason for the defect, an aspiration needle biopsy was performed and ultrasound examination undertaken. In the biopsy smears, both normal spermatozoa and spermatozoa with giant heads were found. On ultrasonography, the echogenicities of both testicles were the same, and normal. DNA flow cytometry was performed to determine the DNA content of the spermatozoa. Two populations of sperm cells were detected, one having a median fluorescent intensity twice as high as that of normal spermatozoa, suggesting a diploid DNA content. Transmission electron microscopy (TEM) was performed to find out whether the altered intensity correlated with the ultrastructure of the spermatozoa. The nuclei of the sperm heads showed a normal chromatin condensation. Semen quality became worse over a period of 2 years, with 60% giant heads in the last sample. The process was considered to be progressive spermatogenic degeneration with diploidy. Relatives examined did not suggest any hereditary predisposition to the problem. The male was still fertile at the time of the last sample collected and sired a litter of 10 healthy puppies.

Animals↗

PubMedDate not supplied

A chemical method to isolate hypothalamic nonapeptides by coupling cyst(e)in with bimane.

Vasopressin, oxytocin as well as other active nonapeptides (vasotocin, etc) are difficult to isolate from tissues. Traditionally they were identified using cumbersome biological assays or immunoassays, commercially unavailable, and with some cross reactivity. Based on the fact that all these peptides have two Cysteines in their molecules we developed a simple, sensitive and specific method to detect them by HPLC after pre-column fluorescent derivatization with monobromobimane (mBBr). The peptides were separated on a Vydac C18 column after reduction with Tris (2-carboxyethyl) phosphine (TCEP) and derivatization with mBBr for 5 minutes in dark. Using this method we were able to detect specific peaks for arginine-, lysine-vasopressin, and vasotocin at levels as low as 10 pmol. The method can be used to detect other active peptides with cyst(e)ins in their molecule, as well.

Arginine Vasopressin↗

PubMedDate not supplied

Increased prevalence of perennial allergic rhinitis in patients with obstructive sleep apnea.

BACKGROUND: Impaired nasal breathing is a risk factor for obstructive sleep apnea syndrome (OSAS). OBJECTIVES: The aim of this study was to determine whether atopy to perennial allergens and existence of perennial allergic rhinitis was a risk factor for OSAS. METHODS: In a case-control study, we compared the proportions of OSAS patients with atopy to perennial allergens and perennial allergic rhinitis to the proportions in patients with chronic obstructive pulmonary disease (COPD). Seventy-two OSAS patients (mean age 60.7 years; 79.4% male) and 44 COPD patients (mean age 63.6 years; 88.6% male) were selected from a hospital outpatients' clinic in Switzerland. All patients completed a respiratory symptom questionnaire, performed spirometry and had a skin prick test for atopy. RESULTS: OSAS patients were significantly heavier than COPD patients (BMI 32.4 +/- (SD) 6.6 vs. 29.2 +/- 6.6 kg/m2, p = 0.04) and had a better lung function than COPD patients (FEV1% predicted 91.3 +/- 19.2 vs. 51.6 +/- 18.9%, p < 0.001). Patients with OSAS were more likely to be sensitized to perennial allergens such as house dust mite (23.6 vs. 4.5%, p = 0.009) and dog (18 vs. 4.5%, p = 0.04) than the COPD patients. Perennial allergic rhinitis (having nose problems [nasal obstruction and/or runny nose and/or sneezing] all year and being atopic to at least one perennial allergen) was reported in 11% of OSAS patients but in only 2.3% of COPD patients (p = 0.15). CONCLUSION: We conclude that subjects with OSAS may have an increased risk of being allergic to perennial allergens and suffer from perennial rhinitis. Awareness of this risk may have important consideration in the clinical situation.

Administration, Intranasal↗

PubMedDate not supplied

Nucleic acid labeling with [3H]orotic acid and nucleotide profile in rats in protein deprivation, enteral and parenteral essential amino acid administration, and 5-fluorouracil treatment.

Rats were fed a 0% casein diet for 1 week, with or without enteral or parenteral administration of essential amino acids, or a 25% casein diet, in one group supplemented with 5-fluorouracil treatment. Ninety minutes before sacrifice the rats were given a tracer of [3H]orotic acid. Incorporation into the acid soluble fraction, RNA, and DNA was determined in liver, small intestine, bone marrow, and kidney. Nucleotide profile was examined in liver and intestine. Protein deficiency caused inter alia a decrease in body weight; a decrease in RNA/DNA ratio and an increase in the specific RNA labeling in liver and kidney; an altered nucleotide profile in the liver; an increase in the nucleotide/DNA and RNA/DNA ratios and a decrease in the specific labeling of the acid soluble fraction, RNA, and DNA in the bone marrow. These changes were prevented to the same extent by giving essential amino acids, either orally or intravenously. The minor changes in intestinal nucleotide profile in protein deprivation were prevented to a slightly larger extent by amino acids orally than parenterally. 5-Fluorouracil treatment gave a decrease in the RNA/DNA ratio in the liver and kidney but an increase in the nucleotide/DNA and RNA/DNA ratios in the bone marrow. Nucleotide profiles were unaltered. The amount of DNA per gram of tissue decreased in bone marrow and increased in kidney. Parenteral administration per se resulted in almost no changes.

Amino Acids↗

PubMedDate not supplied

Nasal mucosal endorgan hyperresponsiveness.

Nonspecific hyperresponsiveness of the upper and lower airways is a well-known characteristic of different inflammatory airway diseases but the underlying mechanisms have not yet been satisfactorily explained. In attempts to elucidate the relation of hyperresponsiveness to disease pathophysiology we have particularly examined the possibility that different airway endorgans may alter their function in allergic airway disease. The nose, in contrast to the bronchi, is an accessible part of the airways where in vivo studies of airway mucosal processes can be carried out in humans under controlled conditions. Different endorgans can be defined in the airway mucosa: subepithelial microvessels, epithelium, glands, and sensory nerves. Techniques may be applied further in the nose to determine selectively the responses/function of these endorgans. Topical challenge with methacholine will induce a glandular secretory response, and topical capsaicin activates sensory c-fibers and induces nasal smart. Topical histamine induces extravasation of plasma from the subepithelial microvessels. The plasma exudate first floods the lamina propria and then moves up between epithelial cells into the airway lumen. This occurs without any changes in the ultrastructure or barrier function of the epithelium. We have therefore forwarded the view of mucosal exudation of bulk plasma as a physiological airway tissue response with primarily a defense function. Since the exudation is specific to inflammation, we have also suggested mucosal exudation as a major inflammatory response among airway endorgan functions. Using a "nasal pool" device for concomitant provocation with histamine and lavage of the nasal mucosa we have assessed exudative responses by analyzing the levels of plasma proteins (e.g., albumin alpha 2-macroglobulin) in the returned lavage fluids. A secretory hyperresponsiveness occurs in both experimental and seasonal allergic rhinitis. This type of nasal hyperreactivity may develop already 30 minutes after allergen challenge. It is attenuated by topical steroids and oral antihistamines. We have demonstrated that exudative hyperresponsiveness develops in both seasonal allergic rhinitis and common cold, indicating significant changes of this important microvascular response in these diseases. An attractive hypothesis to explain airway hyperresponsiveness has been increased mucosal absorption permeability due to epithelial damage, possibly secondary to the release of eosinophil products. However, neither nonspecific nor specific endorgan hyperresponsiveness in allergic airways may be explained by epithelial fragility or damage since nasal absorption permeability (measured with 51CR-EDTA and dDAVP) was decreased or unchanged in our studies of allergic and virus-induced rhinitis, respectively. Thus, the absorption barrier of the airway mucosa may become functionally tighter in chronic eosinophilic inflammation.

Blood Vessels↗