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Chromosome breakage and xenotropic C-type virus in embryonic cultures from New Zealand black mice.

A considerable increase in chromatid and chromosome breaks, as well as excessive fragmentation and "pulverization" of whole metaphase plates was observed in embryonic fibroblast cultures from New Zealand black mice. A C-type RNA virus with a xenotropic host range was isolated from the supernatant fluid of co-cultures of NZB cells and heterologous permissive cells (SIRC cell line). One of the NZB cultures produced this virus without amplification by co-cultivation after spontaneous transformation of the cells. NZB cells are supposed to lack normal restriction of complete xenotropic virus expression and to release this endogenous virus spontaneously at a high level. It is hypothesized that the excessive chromosome damage observed in these cell cultures is related to the permanent production of virus, thus indicating a chromosome breaking effect of endogenous viruses.

Age Factors↗

A temperature sensitive mutant of a Chinese hamster cell line exhibiting high chromosomal breakage.

A temperature sensitive mutant exhibiting a very high level of chromosomal aberrations has been isolated from the Chinese hamster cell line E36. The chromosome aberrations, which include chromosome and chromatid breaks, multiradial configurations, dicentrics, and pulverizations, start to appear 1 h after a shift in temperature from 34 degrees C to 40.5 degrees C. The rate of sister chromatid exchange is not increased in this mutant. Analysis of somatic cell hybrids indicates that the mutation in this temperature sensitive mutant is dominant.

Animals↗

Expectoration disturbances and bronchial obstruction.

UNLABELLED: Two methods for the efficacy evaluation of the respiratory tract clearance by cough, measuring the time of expectoration (Texp) of sputum mixed with hem-containing indicators after their inhalation were used in patients with bronchial obstruction. In the first method, the patients studied inhaled their own hemoglobin (Hb) and in the second one they inhaled a finely pulverized powder of hem-containing substances which were obtained from donor erythrocyte mass. 195 subjects were examined: 44 with intrinsic bronchial asthma (BA), 71 with obstructive bronchitis (OB) and 22 with purulent obstructive bronchitis (POB). Patients expectorating not less than 30 ml/day of sputum were selected. The control group consisted of 18 patients with non-obstructive bronchitis (NOB) and 40 healthy volunteers, nonsmokers. The sputum for analysis after the inhalation of the indicator in healthy persons was collected during coughing stimulated by inhaling a hypertonic solution (15% NaCl+1% NaHCO3). It was found that Texp depends on the form of illness (means +/- SEM): (1) with Hb technique, BA: 41.5 +/- 3.4 h; OB: 59.3 +/- 5.7 h and POB: 128.8 +/- 15.3 h and (2) with the powdered indicator technique, BA: 53.4 +/- 7.6 h; OB: 68.8 +/- 6.6 h and POB: 101.1 +/- 11.8 h. CONTROL GROUP: in patients with NOB, Texp measured with the Hb technique was 31.4 +/- 4.3 h and with the powdered indicator 30.0 +/- 10.3 h. In healthy volunteers, the presence of hem-containing substances in sputum after 36 h was not found.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

RNA-directed DNA polymerase activity in human breast cancer biopsy specimens. Relation to estrogen receptor protein.

The expression of a mouse mammary tumor virus is inducible by hormones, and the virus contains a hormone-responsive element. Viral particles and RNA-directed DNA polymerase (RDDP, EC 2.7.7.7; reverse transcriptase) are both detectable in human breast tumors but the frequency and significance of these findings are unknown. Breast tumor biopsy specimens (from either the primary site or a metastasis), frozen in liquid nitrogen at the time of surgery, were routinely obtained to determine estrogen receptor (ERP) concentration. A sample of the tissue was pulverized, homogenized and centrifuged at low speed to remove nuclei and mitochondria. The supernate was then centrifuged at 225,000 g to obtain the cytosol fraction for estrogen and progestin receptor (PgR) assays. Partially purified membranes for the RDDP assays were prepared from the high-speed pellet by discontinuous sucrose density gradient centrifugation. The RDDP assay involved measuring primer-dependent poly(dT) synthesis in the presence of poly(A) as template and oligo-(dT)12-18 as primer. To date, we have studied biopsy specimens from 46 patients with breast cancer. 27 (59%) had ERP and 23 (50%) were RDDP-positive. There was no significant correlation between ERP concentration and RDDP activity. PgR data were available on 36 of the patients; 17 (47%) were positive. No correlation between RDDP and PgR was apparent. Similarly, there was no correlation between RDDP and clinical stage of the disease.

Adult↗

Abnormal delayed hypersensitivity response to antigens of Candida albicans in alloxan-diabetic mice.

Three antigens of Candida albicans were comparatively evaluated to their ability to elicit delayed hypersensitivity (DH) responses in the mouse footpad test, using alloxan-diabetic and normal mice which were primed with heat-killed C. albicans in complete Freund adjuvant. These antigens were: (1) a preparation of sonically disrupted heat-killed cells; (2) a preparation of soluble cytoplasmic material remaining in the supernatant of a broken-cell suspension centrifuged at 100,000 g; (3) a preparation obtained by extraction of pulverized defatted cells with dilute phenol and sodium bicarbonate in water. After separation by polyacrylamide gel electrophoresis, the major components of soluble cytoplasmic material and dilute phenol extract were identified as a 43-kD protein, and glycoproteins of 21, 27 and 38 kD, respectively. Fifty-eight CD-1 outbred mice, which had received a single intravenous injection of alloxan followed by a 28-day rest period, were randomized with normal littermates to distinct experimental groups. Seven days after sensitization, mice were injected with one of the antigens in the right rear footpad and saline in the left rear footpad and the net specific increase in footpad thickness determined 24 and 48 h later. All three antigens elicited significant responses in sensitized normal mice. The responses of sensitized diabetic mice were clearly inferior to those of sensitized normal mice when heat-killed cells and soluble cytoplasmic material were used. Dilute phenol extract elicited equivalent responses at 24 and 48 h in both primed diabetic and normal mice.

Animals↗

Tissue suspension agglutination: a simple method to screen species-specific and organ-specific reactions.

Agglutination tests with preparations of parenchymatous organs were developed. The tissue suspensions were dried at room temperature after they had been spread as a very thin layer on a glass plate, or otherwise, they were lyophilized. The dried preparations were pulverized and then prepared as stable suspensions in saline. The agglutination test was conducted on a slide by mixing one drop of the tested serum at a convenient dilution with one drop of tissue powder suspension. Agglutination in the form of readily discernible clumps could be assessed after 1-10 min. By means of this procedure, species-specific reactions were studied using suspensions of kidneys of various species. Organ-specific reactions were noted with suspensions of brain and thyroid. Agglutination of thyroid powder was observed with rabbit anti-rabbit thyroid sera as well as with many, albeit not all, sera of patients with Hashimoto's disease.

Agglutination Tests↗

Resolution of proteins in the kidney stone matrix using high-performance liquid chromatography.

The organic matrix accounts for 2-3% of the total stone weight and has been considered to play a role in stone formation and growth. Thus far, fractionation of the matrix proteins has been insufficient due to low resolution and reproducibility. In this report the matrix proteins of 22 stones were resolved by means of high-performance liquid chromatography. Following pulverization, the organic matrix was obtained by dialysis against EDTA. The average content of nondialyzable extractable proteins was 1.6% of the total stone weight. Analysis of the matrix proteins with high-performance gel permeation liquid chromatography and high-performance ion-exchange liquid chromatography has indicated that the protein composition of the stone matrix is identical regardless of the mineral composition. The major component of the matrix proteins was identified as glycoprotein and/or proteoglycan from their absorption to a concanavalin A Sepharose column. Higher molecular weight matrix proteins seem to be polymers or condensation products, since they have been degraded into lower molecular weight subfractions by sodium dodecyl sulfate treatment.

Chromatography, High Pressure Liquid↗

Characterization of a Gla-containing protein from calcified human atherosclerotic plaques.

In this article we describe the isolation of a 4-carboxyglutamic acid (Gla)-containing protein from calcified human atherosclerotic plaques. The protein was extracted from pulverized calcified plaques by demineralization with ethylenediaminetetraacetate and was subsequently purified by anion-exchange fast protein and high-performance liquid chromatography by using ion-exchange and gel-filtration columns. The protein was designated as plaque Gla protein (PGP) and has an apparent mass of 23 kD as estimated from sodium dodecyl sulfate-polyacrylamide gel analysis. By determining the sequence of its first six amino acid residues, the protein was unequivocally demonstrated to be not related to any other known protein. Moreover, no immunological relationship (as tested by Western blot analysis) was found between PGP and other known Gla-containing proteins.

1-Carboxyglutamic Acid↗

Effect of Rotablator atherectomy and adjunctive balloon angioplasty on coronary blood flow.

BACKGROUND: The purpose of this study was to assess serial changes in coronary blood flow velocity before and after Rotablator atherectomy and after adjunctive percutaneous transluminal coronary angioplasty (PTCA). Since Rotablator atherectomy results in luminal enlargement by plaque pulverization and distal embolization, improvement in coronary blood flow could be attenuated despite luminal enlargement. METHODS AND RESULTS: Intracoronary Doppler blood flow velocity measurements were obtained with a Doppler Flowire. Basal average peak velocity (bAPV), hyperemic APV (hAPV), diastolic/systolic velocity ratio (DSVR), and coronary flow reserve (CFR) were assessed before intervention, after Rotablator, and after adjunctive PTCA. Complete clinical, angiographic, and Doppler data were obtained in 22 patients. There was a small but significant difference (P = .02) in resting heart rate and mean arterial pressure before and after Rotablator and after adjunctive PTCA. Minimum lumen diameter increased from 0.8 +/- 0.1 to 1.5 +/- 0.2 to 2.0 +/- 0.1 mm (P < .001), corresponding to decreases in diameter stenosis from 72 +/- 3% to 41 +/- 4% to 36 +/- 3% (P < .001). Although bAPV, hAPV, and DSVR increased significantly (P < .001), CFR remained abnormally low in 19 of 22 patients (despite an increase from baseline to post-PTCA). hAPV > 30 cm/s was the best Doppler correlate of angiographic success. CONCLUSIONS: Rotablator atherectomy and adjunctive PTCA significantly improve distal coronary blood flow velocity and DSVR but not CFR. Failure to normalize CFR could be secondary to parallel increases in bAPV and hAPV, "acquired" microvascular disease due to distal microembolization or spasm, and/or angiographically inapparent dissection or residual stenosis. Adjunctive PTCA contributes significantly to the overall physiological benefit of a combined procedure.

Aged↗

Isolation from human calcium oxalate renal stones of nephrocalcin, a glycoprotein inhibitor of calcium oxalate crystal growth. Evidence that nephrocalcin from patients with calcium oxalate nephrolithiasis is deficient in gamma-carboxyglutamic acid.

We have determined that the organic matrix of calcium oxalate kidney stones contains a glycoprotein inhibitor of calcium oxalate crystal growth (nephrocalcin) that resembles nephrocalcin present in the urine of patients with calcium oxalate stones and differs from nephrocalcin from the urine of normal people. Pulverized calcium oxalate renal stones were extracted with 0.05 M EDTA, pH 8.0; nephrocalcin eluted in five peaks using DEAE-cellulose column chromatography, and each peak was further resolved by Sephacryl S-200 column chromatography. Four of the five DEAE peaks corresponded to those usually found in nephrocalcin from urine; the fifth eluted at a lower ionic strength than any found in urine. Amino acid compositions and surface properties of nephrocalcins isolated from kidney stones closely resembled those of nephrocalcins isolated from urine of stone-forming patients: they differed from normal in lacking gamma-carboxyglutamic acid residues, and in forming air-water interfacial films that were less stable than those formed by nephrocalcin from normal urine.

1-Carboxyglutamic Acid↗

Fewer dopamine transporter receptors in the prefrontal cortex of cocaine users.

The authors investigated dopamine transporter receptor binding in the post-mortem prefrontal cortex of 13 subjects with histories of cocaine use who had positive blood screens for cocaine at autopsy and 13 comparison subjects with no history of cocaine use and negative blood screens for cocaine at autopsy. Synaptosomes from pulverized prefrontal cortex were assayed with [3H]GBR 12935 for dopamine transporter receptor. There was a 38% decrease in number of binding sites but no change in affinity constants in the cocaine users.

Adult↗

Evidence for a schizophrenia vulnerability locus on chromosome 8p in the Irish Study of High-Density Schizophrenia Families.

OBJECTIVE: This study was an attempt to replicate evidence for a vulnerability locus for schizophrenia and associated disorders in the 8p22-21 region reported by Pulver and colleagues. METHOD: The linkage sample of the Irish Study of High-Density Schizophrenia Families consists of 265 multiplex families containing 1,408 individuals. Fifteen markers covering 30 centimorgans on chromosome 8p were tested. Three statistical methods were used: two-point and multipoint heterogeneity lod scores and a multipoint nonparametric test. RESULTS: According to two-point heterogeneity lod scores, the strongest evidence for linkage was found for markers D8S1731 (maximum lod score = 2.00), D8S1715 (maximum lod score = 2.52), and D8S133 (maximum lod score = 2.08) by assuming a phenotypic definition of all psychiatric illness and a range of genetic models. According to multipoint heterogeneity lod scores, the strongest evidence for linkage (maximum lod score = 2.34), found by using a dominant genetic model and a broad definition of the schizophrenia spectrum, extended over a 10-cM region between markers D8S1715 and D8S1739. Multipoint nonparametric linkage found the strongest evidence (maximum z = 2.51) over a broader region when either a diagnosis of core schizophrenia or a narrow definition of the schizophrenia spectrum was used. This putative vulnerability locus was segregating in 10%-25% of the families studied. CONCLUSIONS: This study supports the existence of a vulnerability locus for schizophrenia on chromosome 8p. In this sample, this locus appears to influence the risk of illness in only a modest proportion of families and predisposes to a range of schizophrenia spectrum and possibly nonspectrum disorders.

Chromosomes, Human, Pair 8↗

Prolongation of QT interval as a predictor of no-reflow induced by rotational atherectomy.

Although coronary rotational atherectomy (RA) is widely applied to clinical cases, the incidence of coronary no-reflow associated with it is higher than in percutaneous transluminal coronary angioplasty (PTCA) and stenting. This study was undertaken to predict no-reflow by using conventional electrocardiograms (ECGs). A total of 105 patients who underwent RA (group 1) and 40 who underwent PTCA (group 2) were studied. Eight patients of group 1, all of whom had long calcified coronary lesions, were complicated with no-reflow following RA. Standard 12-lead ECGs were recorded before and throughout the interventional procedures. Maximum and minimum QT intervals and QT dispersion were measured and corrected by heart rate. Corrected and uncorrected QT intervals and QT dispersion were significantly prolonged by RA in group 1 patients without no-reflow: maximum QTc, 428 +/- 28 ms --> 485 +/- 53 ms, p<0.001. The increases in QT intervals were more remarkable in group 1 patients with no-reflow: maximum QTc, 434 +/- 15 ms --> 552 +/- 39 ms, p<0.001. Of the 33 patients with maximum QTc > or = 500 ms, 8 were complicated with no-reflow. No patients with maximum QTc < 500 ms had no-reflow. There was no significant increase in QT intervals in group 2. Adsorption of calcium ions from the myocardium by pulverized calcified atheromatous debris when these pass through coronary capillaries, resulting in transient myocardial hypocalcemia, was considered as a possible mechanism of QT prolongation. Because QT prolongation appears during the initial RA trial, prolonged QT intervals could be a predictor of no-reflow. It is recommended to avoid repetitive RA if marked QT prolongation is observed at the initial RA trial.

Aged↗

Use of a short course of prednisone for treating middle ear effusion. A double-blind crossover study.

This report presents findings of a double-blind crossover prospective study involving the use of a short course of prednisone for the treatment of otitis media with effusion (OME). Subjects were 41 children with persistent OME for three weeks or more despite the use of antimicrobial and/or decongestant therapy. Pulverized prednisone tablets (5 mg) or lactose powder (placebo) were packed in unmarked gelatin capsules and placed in identically coded vials. The dosage schedule was 1 mg/kg/day for the first two days in a divided dose; 0.75 mg/kg/day for the next two days; followed by 5-10 mg/kg/day as a single morning dose for the remaining three days. In addition, all children received concomitant sulfisoxazole suspension of 50 mg/kg/day twice daily. Results for 40 children treated with steroids either initially or following crossover revealed that 70% demonstrated resolution of OME via pneumo-otoscopy and 64% via tympanometry. In addition, we examined the relationship between the ability to resolve effusion with corticosteroids and six variables: 1) duration of OME prior to entry into study, 2) month of year at entry into study, 3) bilateral versus unilateral disease, 4) child's sex, 5) prior use of ventilating tubes and 6) personal or family history of allergy. The results of these comparisons are discussed.

Child↗

Identification, partial characterization, and distribution of versican and link protein in bovine dental pulp.

The dynamics of changes in the cellularity and extracellular matrix composition of dental pulp varies considerably during tooth development and maturation. In this paper, we studied matrix proteoglycans where we hypothesized that they played important roles in structural, spatial, and transport aspects of pulpal development and maintenance. The pulpal tissue was collected from partially erupted bovine incisors, pulverized, and then extracted with 6 M guanidine-HCl. The extract was subjected to anion column chromatography (DEAE-8HR), and the fractions collected were screened by dot-blot immunoassay by means of monoclonal antibodies generated against 4- and 6-sulfated chondroitin sulfate isomers, and keratan sulfate, 2-B-6, 3-B-3, and 5-D-4, respectively. The chondroitin-6-sulfate was the major glycosaminoglycan species and occurred as a large-molecular-weight proteoglycan (> 500 kDa). After further purification, it was subjected to agarose/acrylamide composite gel electrophoresis, and it migrated as a single band stained with Stains-All. The band was immunopositive against antibody 3-B-3 by Western blot analysis. The partial amino acid sequence analyses of the core protein clearly indicated this molecule to be versican. The presence of link protein was also confirmed by Western blot analysis with an anti-link protein monoclonal antibody, 8-A-4. Furthermore, immunohistochemical study indicated that the distributions of versican and link protein coincide in the dental pulp and are enriched in the peripheral area of the tissue just beneath the odontoblast layer. Since the dental pulp contains hyaluronan, versican may bind to hyaluronan via its hyaluronan-binding domain, where this association is stabilized by link protein. This complex, then, could form large hydrated proteoglycan aggregates that fill the extracellular space, support odontoblasts, and/or facilitate the transport function of metabolites and nutrients within the tissue.

Amino Acid Sequence↗

Oyster shell as substitute for aggregate in mortar.

Enormous amounts of oyster shell waste have been illegally disposed of at oyster farm sites along the southern coast of Korea. In this study to evaluate the possibility of recycling this waste for use as a construction material, the mechanical characteristics of pulverized oyster shell were investigated in terms of its potential utilization as a substitute for the aggregates used in mortar. The unconfined compressive strengths of various soil mortar specimens, with varying blending ratios of cement, water and oyster shell, were evaluated by performing unconfined compression tests, and the results were compared with the strengths of normal cement mortar made with sand. In addition, the effect of organic chemicals on the hardening of concrete was evaluated by preparing ethyl-benzene-mixed mortar specimens. The long-term strength improvement resulting from the addition of fly ash was also examined by performing unconfined compression tests on specimens with fly-ash content. There was no significant reduction in the compressive strength of the mortars containing small oyster shell particles instead of sand. From these test data, the possible application of oyster shells in construction materials could be verified, and the change in the strength parameters according to the presence of organic compounds was also evaluated.

Animals↗

Cardioprotective effect of the Hibiscus rosa sinensis flowers in an oxidative stress model of myocardial ischemic reperfusion injury in rat.

BACKGROUND: The present study investigates the cardioprotective effects of Hibiscus rosa sinensis in myocardial ischemic reperfusion injury, particularly in terms of its antioxidant effects. METHODS: The medicinal values of the flowers of Hibiscus rosa sinensis (Chinese rose) have been mentioned in ancient literature as useful in disorders of the heart. Dried pulverized flower of Hibiscus rosa sinensis was administered orally to Wistar albino rats (150-200 gms) in three different doses [125, 250 and 500 mg/kg in 2% carboxy methyl cellulose (CMC)], 6 days per week for 4 weeks. Thereafter, rats were sacrificed; either for the determination of baseline changes in cardiac endogenous antioxidants [superoxide dismutase, reduced glutathione and catalase] or the hearts were subjected to isoproterenol induced myocardial necrosis. RESULTS: There was significant increase in the baseline contents of thiobarbituric acid reactive substances (TBARS) [a measure of lipid per oxidation] with both doses of Hibiscus Rosa sinensis. In the 250 mg/kg treated group, there was significant increase in superoxide dismutase, reduced glutathione, and catalase levels but not in the 125 and 500 mg/kg treated groups. Significant rise in myocardial thiobarbituric acid reactive substances and loss of superoxide dismutase, catalase and reduced glutathione (suggestive of increased oxidative stress) occurred in the vehicle treated hearts subjected to in vivo myocardial ischemic reperfusion injury. CONCLUSION: It may be concluded that flower of Hibiscus rosa sinensis (250 mg/kg) augments endogenous antioxidant compounds of rat heart and also prevents the myocardium from isoproterenol induced myocardial injury.

Administration, Oral↗

Hair analysis used to assess chronic exposure to the organophosphate diazinon: a model study with rabbits.

The main purpose of the present study was to determine whether hair analysis would be a suitable method to assess chronic exposure of rabbits to the pesticide diazinon. A controlled study was designed, in which white rabbits of the New Zealand variety were systemically exposed to two dosage levels (15 mg/kg per day and 8 mg/kg per day) of the pesticide, through their drinking water, for a period of 4 months. Hair samples from the back of the rabbits were removed before commencing the experiment and at the end of the dosing period. Parallel experiments with spiked hair were carried out in order to design a simple and efficient method of extraction of diazinon from hair. The hair was pulverized in a ball mill homogenizer, incubated in methanol at 37 degrees C overnight, liquid-liquid extracted with ethyl acetate and measured by chromatography techniques (GC-NPD and GC-MS) for confirmation. The concentration of the diazinon in the hair of the exposed animals ranged from 0.11 to 0.26 ng/mg hair. It was concluded that there is a relationship between the administered dose and the detected pesticide concentration in hair. Finally, it seems that hair analysis may be used to investigate chronic exposure to the pesticide.

Animals↗