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C Andersson

Publications and source records attributed to C Andersson.

At least 163 records · Page 9Linked to original sources
PubMed1986

Isolation and characterization of variant IGF-1 as well as IGF-2 from adult human brain.

The forms of somatomedin present in the adult human brain have been characterized in this study. Two peptides were purified by acidification, size exclusion chromatography, affinity chromatography, FPLC and HPLC. Structural analysis identified these peptides as the variant form of IGF-1 with a truncated N-terminal region earlier isolated from human fetal brain and IGF-2. The presence of the truncated IGF-1 variant and IGF-2 in the human CNS suggests their role as neuropeptides.

Adult↗
PubMed1986

Characterization of somatomedins from human fetal brain: identification of a variant form of insulin-like growth factor I.

A fetal form of somatomedin (insulin-like growth factor) that crossreacts in the fetal brain radioreceptor assay has been proposed to exist in humans. Using this assay to monitor activity during purification, we have isolated a variant form of insulin-like growth factor I (IGF-I) from human fetal brain tissue. The variant IGF-I showed potent crossreaction in the fetal brain radioreceptor assay and stimulated DNA synthesis in fetal brain cells in vitro. Structural analysis revealed the variant IGF-I to have a truncated NH2-terminal region compared to IGF-I isolated from serum. An additional peptide, which displayed less potent crossreaction in the fetal brain radioreceptor assay, was also isolated from the human fetal brain. Partial amino acid sequence analysis revealed identity to insulin-like growth factor II.

Amino Acid Sequence↗
PubMed1986

A prospective randomized study of continuous peritoneal lavage postoperatively in the treatment of purulent peritonitis.

Peritoneal lavage performed postoperatively in the treatment of purulent peritonitis was evaluated in a prospective randomized study. Patients with free purulent peritonitis due to perforated appendicitis or colonic perforation were treated with intravenous infusion of cefuroxime and metronidazole. The patients were randomly allocated to treatment with or without continuous postoperative peritoneal lavage. The patients were kept under observation for postoperative septic intra-abdominal complications. Of the 79 patients, 41 were treated with lavage postoperatively and 38 were not. No postoperative abscess or other septic intra-abdominal complication was found in any patient. In ten, the postoperative lavage was interrupted because of technical complications or complaints of discomfort by the patient. In this study, no clinical benefit of continuous peritoneal lavage postoperatively in the treatment of purulent peritonitis was noted. Lavage done postoperatively is expensive and seems to carry a risk of complications. Thorough rinsing of the infected abdominal cavity perioperatively and adequate antibiotic treatment, including an antianaerobic agent, seem to be effective in preventing intra-abdominal septic complications.

Adult↗
PubMed1984

Peptide utilization by oral streptococci.

Streptococcus mitis ATCC 903 and Streptococcus sanguis 804 could utilize large peptides present in proteose peptone as their sole source of nitrogen but grew poorly in amino acid medium. By contrast, Streptococcus mutans BHT and S. mutans IB grew in amino acid medium but could not utilize large peptides. Streptococcus sp. strain Bravato had requirements for both peptides and amino acids. Peptide size did not seem important for the utilization of peptides by S. mitis except that dipeptides were not utilized. Large peptides were essential for depressed hyaluronidase synthesis in nongrowing S. mitis. Intracellular aminopeptidase activities were high in S. mitis ATCC 903 and Streptococcus sp. strain Bravato, intermediate in S. sanguis 804, and low in S. mutans BHT and S. mutans IB.

Aminopeptidases↗
PubMed1984

Spectral scan of Orion A and IRC+10216 from 72 to 91 GHz.

The spectra of the Orion KL molecular cloud and the envelope of the carbon star IRC+10216 have been surveyed at 1 MHz resolution over the interval 72.2-91.1 GHz to a sensitivity (in terms of main beam brightness temperature) usually better than 0.1 K. Some complementary data have been obtained at selected higher and lower frequencies. Detected lines are reported in Table 1. Approximately 170 lines from 24 known interstellar molecules were detected in Orion (Table 2); the corresponding numbers for IRC+10216 are 45 and 12, respectively (Table 3). Some 15 recombination lines of hydrogen (alpha, beta, gamma, delta) and helium (alpha) are also identified in Orion (Table 2). More than 100 of the Orion lines can be attributed to astronomically new transitions, the vast majority of which belong to only five species: SO2 (in total 17 lines), CH3CH2CN (19), CH3OH (16), (CH3)2O (21) and CH3OOCH (32). The rare occurrence of unidentified lines (5 definite lines in each object) is significant, possibly indicating that, in the case of Orion, the dominant chemical constituents are recognized. For IRC+10216 our results are less conclusive in this respect, partly due to the less effective excitation conditions in the envelope. We report (or confirm) the existence in these sources of several molecules which previously had only been found elsewhere: methylformate (CH3OOCH), isocyanic acid (HNCO), cyanodiacetylene (HC5N), vinyl cyanide (CH2CHCN), ketene (H2CCO) and probably the formyl radical (HCO) in Orion; and in IRC+10216 the first species containing the methyl group, methyl cyanide (CH3CN). The first astronomical detections of the isotopically rare species 34SO2 (Orion), and 29SiS and, tentatively, Si34S (IRC+10216) are also reported, as well as a number of newly identified high energy methanol lines. Multi-transition analysis of several molecular species is presented and gives information on physical conditions and chemical abundances in the Orion KL region (Tables 5 and 6). Gaussian decomposition of 0.25 MHz resolution profiles into "ridge", "hot core" and "plateau" emissions is used in an attempt to individually characterize these subregions. Striking chemical differences among the subregions emerge: (i) The estimated abundance ratios [SO, SO2, SiO]/[CO] are enhanced by a factor approximately > 100 in the plateau relative to the ridge, [HCN, HDO]/[CO] by a factor approximately > 10, while [HCO+, OCS, HNC, HC3N]/[CO] seem to be less enhanced in the plateau (by a factor approximately >10). (ii) The ratio of chemically saturated to unsaturated species differs markedly between the hot core and the ridge cloud (specifically HC3N vs. CH3CH2CN, and CH2CHCN) with the latter region more closely resembling both the cloud TMC-1 and IRC+10216. The chemical selectivity in the ridge cloud is very pronounced, with CH3OH as abundant as H2CO while (CH3)2O and CH3OOCH are an order of magnitude less abundant. We have neither detected CH3CH2OH and CH3COOH (acetic acid)--isomers of the two latter species, respectively--nor HCOOH, CH3CHO, or CH2CHCHO. H2C2O (ketene) is two orders of magnitude less abundant than H2CO. From the isotopic species of CH3OH, OCS, and HC3N we find 12C/13C approximately 40, in agreement with independent estimates by others and a factor of two lower than the solar system isotope ratio. The observed intensities of the hydrogen recombination lines are consistent with optically thin LTE emission, indicating that our He alpha/H alpha intensity ratio is relatively model independent and thus is an accurate measure of the helium abundance. We estimate a helium abundance by mass of 28 +/- 2%. The excitation conditions and relative abundances in the IRC+10216 envelope are reviewed. It is emphasized that the low detection rate of molecular lines in this object does not necessarily imply a poorer chemistry compared with that in interstellar clouds, but is partly a reflection of low abundances and unsatisfied excitation requirements. However, the CH3CN data indicate less favorable conditions for species containing methyl groups in this environment relative to interstellar clouds. The chemistry appears to be dominated by linear, especially unsaturated carbon-chain, molecules (Table 9). Rotational temperatures for HC3N and HC5N are estimated to be on the order of 15 K. Guided by the selective chemistry in IRC+10216 we tentatively assign two close doublets at 76.2 and 98.0 GHz to the radical C3H. In addition to Orion KL and IRC+10216 a few other sources have been observed, however in a less systematic way. We present selected data for W 51 M. The W 51 M methanol data, including newly identified high energy lines, indicate a rotational temperature of about 100 K.

Astronomy↗
PubMed1983

Protoplast formation and localization of enzymes in Streptococcus mitis.

Cells of Streptococcus mitis ATCC 903 were converted to stable protoplasts by the cell wall-degrading M-1 enzyme of the mutanolysin complex isolated from Streptomyces globisporus. Over 90% of total glucokinase (EC 2.7.1.2), aminopeptidase (EC 3.4.11.1), and dextranglucosidase (EC 3.2.1.70) was recovered in the cytoplasmic fraction, whereas over 20% of total invertase (beta-fructofuranosidase: EC 3.2.1.26) was released during protoplast formation. ATPase (EC 3.6.1.3). chymotrypsin-like protease (EC 3.4.21.1), arginine aminopeptidase (EC 3.4.11.6), and lactate dehydrogenase (EC 1.1.1.27) were detected in Triton X-100 extracts of the cytoplasmic membrane fraction by crossed immunoelectrophoresis in combination with enzyme-staining procedures. By these methods, NADH dehydrogenase (EC 1.6.99.3), aminopeptidase, and lactate dehydrogenase were detected in the cytoplasmic fraction. Aminopeptidases in the cytoplasmic fraction differed from this activity in the membrane fractions in electrophoretic mobility and substrate specificity.

Cell Membrane↗
PubMed1978

Isoelectric focusing studies on the beta-fructofuranosidases and alpha-glucosidases of Streptococcus mitis.

Extracts of Streptococcus mitis ATCC 903 were analysed for beta-fructofuranosidase and alpha-glucosidase activities by isoelectric focusing in thin-layer polyacrylamide gels combined with zymogram procedures. Three bands of activity were visualized in the gels after incubation with sucrose (pI 4.05, 4.25 and 4.85) and three other bands after incubation with p-nitrophenyl alpha-D-glucopyranoside (pI 3.90, 4.45 and 4.65). The enzymes responsible for the reaction with sucrose were identified as beta-fructofuranosidases (EC 3.2.1.26) for the following reasons: identical enzyme bands were visualized in the gels after incubation with raffinose; no enzyme bands appeared in the gel after incubation with the alpha-glucosides maltose, turanose, trehalose and melezitose; and the soluble fraction hydrolysed sucrose to equimolar amounts of glucose and fructose.

Glucosidases↗
PubMedDate not supplied

Computer-assisted image analysis techniques allow a characterization of the compartments within the basal ganglia. Focus on functional compartments produced by d-amphetamine activation of the c-fos gene and its relationship to the glucocorticoid receptor.

A new computer-assisted image analysis procedure was developed for the analysis of striatal compartments of the rats visualized in this case by means of c-fos immunocytochemistry after morphine and/or d-amphetamine treatments. In particular it has been shown that d-amphetamine can induce an activation of the c-fos early gene in various subregions of the neostriatum and that morphine treatment can antagonize this activation. A different pattern of morphine antagonistic action could be detected at the rostral versus the caudal striatal level. In fact, at the rostral level the morphine antagonistic action was very marked only in the dorsomedial striatum, while at the caudal level the morphine antagonistic action was marked in all subregions. The developed computer-assisted procedure can detect differences in the pattern of distribution of profiles present in a certain neuroanatomical area. Therefore, this procedure may represent a powerful tool to study integrative functional compartments in the neostriatum. In the present study high level integrative compartments appear to be created by D1/mu-opiate receptor interactions especially within the classical patch system.

Animals↗
PubMedDate not supplied

Development of high-grade lymphoma in Helicobacter pylori-infected C57BL/6 mice.

Helicobacter pylori infection is associated with chronic gastritis, peptic ulcer disease, gastric adenocarcinoma and MALT lymphoma. Mice with H. pylori infection develop severe gastritis and atrophic changes in their stomachs after 6 months. We followed H. pylori-infected animals for 13 months to find out whether dysplasia, carcinoma or lymphoma developed. Six-week-old C57BL/6 mice were infected with the CagA-positive and VacA-positive H. pylori mouse-passaged strain 119/95, fed a low antioxidant diet, and kept in microisolated cages. Histopathological changes were examined after 13 months' infection. All H. pylori-inoculated mice (n = 5) developed a gastric squamous papilloma with nagging of the lamina muscularis after 13 months. Three out of five animals developed high-grade B-cell lymphoma derived from a MALT lymphoma at the squamous-corpus border with manifestations also in the liver, spleen and kidney. There was a suspicion of local gastric lymphoma in the two remaining mice but with no significant changes in the liver, spleen or kidney. The normal control mice showed no pathological changes in any of these organs. It is concluded that this mouse model with infection by the CagA-positive, vac-toxin-producing H. pylori strain 119/95 is suitable for use in the study of lymphoma development and also development of squamous cell papilloma with proliferative features.

Animals↗