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B Lindberg

Publications and source records attributed to B Lindberg.

At least 73 records · Page 4Linked to original sources
PubMed1990

Structural studies of the capsular polysaccharide from Aerococcus viridans var. homari.

The capsular polysaccharide from Aerococcus viridans var. homari has been investigated, using n.m.r. spectroscopy, methylation analysis, and specific degradations as the main methods. The polysaccharide is composed of tetrasaccharide repeating-units having the following structure. (Formula; see text) In this structure, D-QuiN stands for 2-amino-2,6-dideoxy-D-glucose (quinovosamine). Two of the three acidic sugars found, namely, L-altruronic acid and 4-O-[(S)-1-carboxyethyl]-D-glucose, have not been found in any other natural source. As evident from the n.m.r. spectra, the L-altruronic acid is not present in the 1C4 conformation, but flips to a conformation close to this on carboxyl reduction.

Carbohydrate Sequence↗
PubMed1990

Distribution of substituents in 2-hydroxypropyl ethers of cyclomaltoheptaose.

The distribution of substituents in 2-hydroxypropyl ethers of cyclomaltoheptaose, prepared by alkylation of the carbohydrate with propylene oxide in aqueous sodium hydroxide, was investigated. The samples were fully methylated and hydrolyzed, and the resulting mixture of alkylated sugars analyzed as their alditol acetates by g.l.c.-m.s. High and low alkali concentration favored the formation of 2-hydroxypropyl ethers at O-6 and O-2, respectively; substitution at O-2 increased the reactivity of O-3. The overall extent of substitution had only secondary effects on the relative reactivities of O-6 and O-2, and the 2-hydroxypropyl groups remained unevenly distributed among the glucose residues, even when the overall substitution increased. Only small proportions of the isomeric 2-(1-hydroxypropyl) ethers were formed, and the percentage of oligopropylene glycol ethers was also low.

1-Propanol↗
PubMed1990

Disposition of morphine-3-glucuronide in the pregnant rhesus monkey.

Morphine-3-glucuronide (M3G) is the major metabolite of morphine and is present in the circulation of persons treated with morphine or abusing heroin. This project was designed to study the kinetics of M3G in the foeto-maternal compartment, since this metabolite may be of relevance for the abstinence syndrome observed in neonates of pregnant abusers. The kinetics of M3G were studied in two non-pregnant and four pregnant Rhesus monkeys. M3G was given as a bolus injection in four of the animals and as a long-term infusion for 12 hr in two animals. M3G passed slowly across the placenta to the foetus and amniotic fluid. After 10 hr of M3G infusion, the foetal plasma M3G concentration was measured in two cases and found to be 37% and 72%, respectively, of the maternal concentration.

Amniotic Fluid↗
PubMed1990

Acupuncture before delivery: effect on pain perception and the need for analgesics.

Pain experience and the amount of analgesics needed during labor were studied in 32 primiparous women who had received repeated treatment with acupuncture (AP) during the month prior to term and in 16 nontreated primiparous women. The women's psychological profiles were evaluated by a psychiatric interview at week 38 of pregnancy. Treatment with AP did not reduce the need for analgesics in labor. During labor, all women experienced successively rising pain irrespective of whether or not they had been treated with AP prior to labor or delivered under local anesthesia. Experience of pain was not reduced in subjective assessments in women treated with AP. There was a strong correlation between assessments of pain made during labor and 6 months after delivery. In the group that did not receive AP, cerebrospinal fluid dynorphin A was significantly lower in parturients who chose epidural anesthesia.

Acupuncture Analgesia↗
PubMed1990

Transplacental transfer of morphine in man.

The transplacental transfer of morphine and morphine-3-glucuronide (M3G) was studied in five cases of suspected Rh-isoimmunization. Ultrasound-guided fetal blood sampling from the umbilical vein was carried out as a diagnostic procedure before intrauterine blood transfusion. Morphine was given as a parenteral premedication to the mother at a dose of 0.13-0.20 mg/kg bw. Fetal blood was sampled 5-74 minutes after the morphine administration. These five women were investigated on 14 different occasions. The plasma concentrations of morphine and M3G were measured in blood samples collected simultaneously from mother and fetus. The feto-maternal ratio of morphine was 0.96 at five minutes and remained close to 1.0 in most samples taken later. At 12 minutes the ratio of M3G was less than 0.002 and between 0.2 and 0.6 in the later samples. The feto-maternal plasma ratios of morphine and M3G did not change over the studied period in one woman investigated five times between gestational weeks 26 and 32. This is the first time transplacental transfer of morphine has been quantified in man. Our results demonstrate a rapid transplacental passage and equilibration of morphine between mother and fetus.

Female↗
PubMed1990

Maternal kinetics of morphine during labour.

The disposition of parenterally administered morphine was investigated in 13 nulliparous parturients in comparison with six healthy non-pregnant women of child-bearing age. Morphine was administered intravenously or intramuscularly and repeated venous blood samples were taken up to 360 minutes after the dose, or until delivery. At delivery samples were taken from the umbilical artery and vein. The plasma concentrations of morphine and M3G (morphine-3-glucuronide) were determined. The elimination half-life of morphine was shorter (43 +/- 19 versus 84 +/- 40 min) and the plasma clearance larger (3.4 +/- 1.4 versus 2.0 +/- 0.5 l/min) in the parturients than in the non-pregnant women. There was no difference in the apparent volume of distribution of morphine between those two groups. The time to peak plasma concentration of M3G was shorter (11 +/- 3 versus 21 +/- 6 min) and the M3G/morphine concentration ratio at 10 minutes higher (6.4 +/- 1.0 versus 3.4 +/- 0.6) in parturients than in non-pregnant women. In all but one infant, three of whom were born within three hours after the dose, no morphine was detectable. The rapid elimination of morphine by the parturients, resulting in only a short period of intrauterine exposure of the fetus to this drug, may be of clinical importance in the choice of obstetric analgesic agent.

Adolescent↗
PubMed1989

[PET--new ways inside the body].

Using positron-emitting short-lived radionuclide tracers, a wide range of substances can now be labelled without their biological properties being affected. Positron emission tomography (PET) enables the distribution and metabolism of the labelled substance to be studied in different organs. By providing quantitative, locational, functional and biochemical information difficult to obtain by other means, PET opens up new possibilities, both diagnostic, pathophysiological and therapeutic, in a broad spectrum of medical practice. The development of the technique is described, with particular reference to its use at Uppsala.

Abdominal Neoplasms↗
PubMed1988

Structural studies of the Escherichia coli O-149 O-antigen polysaccharide.

The structure of the O-antigen polysaccharide from Escherichia coli O-149 has been investigated; methylation analysis, partial hydrolysis with acid, and n.m.r. spectroscopy were the principal methods used. It is concluded that the polysaccharide is composed of trisaccharide repeating-units having the following structure. (Formula: see text). The absolute configuration at the acetalic carbon atom of the pyruvic acid residue is S.

Antigens, Bacterial↗
PubMed1988

Structural studies of the capsular polysaccharides from Klebsiella types 8 and 82, a reinvestigation.

The structures of the capsular polysaccharides elaborated by Klebsiella types 8 (K8) and 82 (K82) have been reinvestigated. N.m.r. spectroscopy of the original and chemically modified polysaccharides was the principal method used. It is concluded that the polysaccharides are composed of repeating units having the following structures. (Formula: see text). The presence of L-glutamic acid, linked as an amide to the carboxyl group of a uronic acid, has not been observed hitherto in bacterial polysaccharides.

Carbohydrate Conformation↗
PubMed1988

Structural studies of the O-antigen polysaccharide of Salmonella thompson, serogroup C1 (6,7).

The structure of the O-antigen polysaccharide of Salmonella thompson, serogroup C1 (6,7) has been investigated mainly by methylation analysis, n.m.r. spectroscopy, specific degradations by a phage-associated enzyme, N-deacetylation-deamination, and f.a.b.-m.s. It is concluded that the structure involves the following repeating unit. (formula; see text) There are two populations of chains, with and without alpha-D-glucopyranosyl groups, 3-linked to an alpha-D-Manp residue, and only the latter type is hydrolysed by the phage enzyme. The alpha linkage of the third Manp residue is cleaved by the O14 phage enzyme. The structure, with or without the alpha-D-glucopyranosyl group, represents the biological repeating-unit.

Carbohydrate Conformation↗
PubMed1988

Structural studies of the capsular polysaccharide from Streptococcus pneumoniae type 18F.

The structure of the capsular polysaccharide elaborated by Streptococcus pneumoniae type 18F (S18F) has been investigated by using n.m.r. spectroscopy, methylation analysis, and characterisation of oligosaccharides obtained on partial hydrolysis. It is concluded that the polysaccharide is composed of pentasaccharide repeating-units having the following structure. (formula; see text) In this structure, the absolute configuration of the glycerol phosphate moiety has not been determined, but is assumed to be D-glycerol 1-phosphate (sn-glycerol 3-phosphate). The location of an O-acetyl group at O-6 of the terminal alpha-D-glucopyranosyl groups is tentative only.

Carbohydrate Conformation↗
PubMed1988

Structural studies of the capsular polysaccharide from Streptococcus pneumoniae type 18A.

The structure of the capsular polysaccharide (S18A) elaborated by Streptococcus pneumoniae type 18A has been investigated by using methylation analysis and n.m.r. spectroscopy. It is concluded that the polysaccharide is composed of pentasaccharide repeating-units having the following structure. (formula; see text) In this structure, the absolute configuration of the glycerol 1-phosphate moiety has not been determined but is assumed to be D from biosynthesis considerations. The structure of S18A is, as expected, closely similar to those determined for S18F and S18C.

Carbohydrate Conformation↗