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K Kristensen

Publications and source records attributed to K Kristensen.

At least 55 records · Page 3Linked to original sources
PubMed1994

Enantioselective high-performance liquid chromatographic method for the determination of methadone in serum using an AGP and a CN column as chiral and analytical column, respectively.

A simple and sensitive HPLC method with ultraviolet absorption detection at 200 nm is described for the determination of methadone enantiomers in human serum, using dextropropoxyphene as an internal standard and organic solvent extraction. Separation was performed on two serially coupled columns, CN and Chiral AGP, with a mobile phase consisting of acetonitrile, dimethylocytlamine and phosphate buffer. Using 1.0 ml of serum, 5 nmol/1 of each enantiomer could be determined with an acceptable precision. No interactions from several drugs were observed. The method has been successfully used in a pharmacokinetic study. More than 2500 serum samples have been separated on the same AGP column with acceptable selectivity and resolution.

Chromatography, High Pressure Liquid↗
PubMed1994

[Vaccination of splenectomized children. Antibody response to Haemophilus influenzae type b conjugate vaccine].

Twenty splenectomized children and adolescents aged four to 18 years were immunized once with a Haemophilus influenzae type b (Hib) polysaccharide tetanus toxoid conjugate vaccine. Prior to vaccination, ten of 20 patients had anticapsular antibodies below what could be considered the minimum protective level in the splenectomized (0.6 microgram per ml), whereas all obtained high antibody levels after vaccination. In addition, one infant with congenital asplenia was vaccinated at two, four, and six months of age, and was shown to respond well after the second and third injections, obtaining serum antibody concentrations of 0.84 and 10.7 microgram per ml respectively. Because asplenic individuals have an increased risk of invasive Hib infection, these data suggest that vaccination of such individuals against Hib may be justified.

Adolescent↗
PubMed1994

Opposite effects of actively and passively acquired immunity to the carrier on responses of human infants to a Haemophilus influenzae type b conjugate vaccine.

Vaccination of infants with Haemophilus influenzae type b (Hib) capsular polysaccharide (HibCP) coupled to carrier proteins has proven protective against invasive Hib diseases in several trials. However, insufficient immunogenicity has been noted in certain populations. Therefore, studies analyzing factors influencing the antibody response to conjugate vaccines are needed. In this study, the response to HibCP coupled to tetanus toxoid (TT) was examined in relation to (i) priming with or coadministration of the carrier protein and (ii) the levels of passively acquired maternal TT antibodies. One hundred forty-four infants were vaccinated with HibCP-TT at 5 and 6 months. They were randomized into three groups that received TT as part of a diphtheria-tetanus-polio vaccine at either 6 and 7 months (group A), 5 and 6 months (group B), or 4 and 5 months (group C). Maternally acquired TT antibodies inhibited the anti-HibCP response to the first HibCP-TT dose in groups A and B (r = -0.5 and -0.4, respectively; P < 0.005). In these groups, infants with prevaccination anti-TT levels above the median failed to reach the defined long-term protective level of HibCP antibodies (1 microgram/ml) more often than infants with low prevaccination levels after the first (P = 0.0001) and the second (P = 0.01) doses of HibCP-TT. In contrast, active priming with TT at 4 months resulted in a threefold-higher median level of anti-HibCP (group C; 1.34 micrograms/ml) than in the unprimed group (group A; 0.40 microgram/ml) after the first dose of HibCP-TT (P = 0.01). Coadministration of TT had no enhancing effect (group B; 0.58 microgram/ml). No significant differences between the median anti-HibCP levels were seen after the second HibCP-TT dose (6.72, 9.63, and 11.44 micrograms/ml in groups A, B, and C, respectively; P = 0.25).

Antibodies, Bacterial↗
PubMed1993

[Finger tip injuries. A comparative study of silver sulfadiazine and fucidin gauze].

Eighty-eight superficial finger-tip lesions were randomized after thorough cleaning to either silver sulphadiazine treatment of Fucidin fusidic acid gauze. In the silver sulphadiazine group the wounds were covered with a non-sterile PVC gloce and redressed at least every third day; in the other group Fucidin gauze was applied and a tubigauze dressing was left in situ for ten days, after which a new dressing was applied. All patients were treated until healed and followed for at least six months after injury. Patients in the silver sulphadiazine group required shorter time for healing and shorter sick leave. The treatment is recommended because of the easy procedure and the good results.

Adult↗
PubMed1992

General surgery in patients aged 80 years and older.

This study reviews 594 surgical admissions, of patients aged 80 years and older, to departments of general surgery during 1 year. Half of the patients were admitted as emergencies and 60 per cent underwent surgery. The operative mortality rate was 8 per cent and the overall mortality rate for all admissions 9 per cent. The number of complications and the mortality rate after surgery increased in emergency cases and in patients with coexisting disease. Of all admissions, 72 per cent were uncomplicated and in 70 per cent patients could be discharged directly home; such patients do not generally take up beds and are discharged as soon as medical care is no longer indicated. The number of admissions of patients over 80 years of age will increase by about 30 per cent during this decade and, unless additional resources are provided to meet this challenge, new standards must be considered for the distribution of resources and of indications for surgery in both young and old.

Aged↗
PubMed1992

Stereospecific gas chromatographic method for determination of methadone in serum.

rac-Methadone is used clinically for the chronic maintenance treatment of heroin addiction and for the relief of pain. As the pharmacological activity of methadone is due primarily to the (-)-(R)-enantiomer, stereospecific measurements of methadone serum concentrations in methadone-treated patients are expected to be more relevant for clinical studies than earlier described total drug measurements. This study describes a stereospecific gas chromatographic (GC) method for the determination of methadone in serum. The extracted methadone was derivatizised with (-)-menthyl chloroformate. The diastereometric derivatives were analysed by GC on a capillary column and detected with a nitrogen-phosphorus detector. The resolution factor obtained for the methadone enantiomers was 1.1 with a relatively short time of analysis (30 min). By analysing the pure (-)-(R)-enantiomer, no racemization was seen during the analysis. The lower limit of quantitation was 75 nmol/l for each enantiomer. Measurements of the ratio between (-)-(R)- and (+)-(S)-methadone concentrations in serum from five methadone-treated patients showed interindividual differences (range 0.5-1.1). The patient results correlated well with those from another GC method measuring total methadone.

Chromatography, Gas↗
PubMed1992

Relation between enzyme-linked immunosorbent assay and radioimmunoassay for detection of antibodies to the capsular polysaccharide of Haemophilus influenzae type b.

The measurement of antibodies to the capsular polysaccharide (PRP) of Haemophilus influenzae type b (Hib) is important because vaccines inducing such antibodies are now available. We developed and evaluated an enzyme-linked immunosorbent assay (ELISA) for detection of these antibodies based on direct coating of the plates with tyraminated PRP. The assay fulfilled the requirements for parallel line assays; it was sensitive, specific, and reproducible with a coefficient of variation between days of 19%. Results from the ELISA were compared with results from radioimmunoassay and a correlation coefficient of 0.93 was found. Results obtained by the two methods were proportional and the relation was independent of the antibody level. The relation between them was also unaffected by the contribution of different antibody isotypes, indicating that these were measured to the same extent by both methods. ELISA employing direct coating of the plates with tyraminated PRP represents a useful alternative for detection of antibodies when studying immunogenicity of Hib vaccines.

Antibodies, Bacterial↗
PubMed1992

Antibody response to a Haemophilus influenzae type b polysaccharide tetanus toxoid conjugate vaccine in splenectomized children and adolescents.

20 children and adolescents 4-18 years old and splenectomized for various reasons (spherocytosis (n = 6), idiopathic thrombocytopenia (n = 8), other (n = 6)) were immunized once with a Haemophilus influenzae type b (Hib) polysaccharide tetanus toxoid conjugate vaccine. Prior to vaccination 10/20 patients had anticapsular antibodies below what could be considered the minimum protective level in splenectomized (0.6 micrograms/ml), whereas all obtained high antibody levels after vaccination. In addition 1 infant with congenital asplenia was vaccinated at 2,4 and 6 months of age, and was shown to respond well after the second and third injection with serum antibody concentrations of 0.84 and 10.7 micrograms/ml respectively. Because asplenic individuals have an increased risk of invasive Hib infection, these data suggest that vaccination of such individuals against Hib may be justified.

Adolescent↗
PubMed1991

Influence of prevaccination immunity on the human B-lymphocyte response to a Haemophilus influenzae type b conjugate vaccine.

The purpose of this study was to investigate whether preexisting immunity to components of a polysaccharide-protein conjugate influences the B-lymphocyte response to vaccination with the conjugate. Thirty-two healthy adults were vaccinated once or twice with a conjugate (PRP-D) consisting of Haemophilus influenzae type b capsular polysaccharide (PRP) and diphtheria toxoid (DT), and the response was related to the prevaccination levels of PRP and DT antibodies. Positive correlations were found between increases in plasma PRP (median, 32.0 micrograms/ml) and DT (1.14 IU/ml) antibodies and numbers of circulating PRP and DT antibody-secreting cells (AbSC) (postvaccination days 6 to 9). The B-cell responses (antibody response and AbSC) to both PRP and DT correlated positively with prevaccination levels of anti-DT. DT AbSC appeared earlier (peak, day 7) than PRP AbSC (peak, day 8). Individuals whose PRP AbSC peaked early (day 7) had higher prevaccination anti-DT levels than those who peaked later (P less than 0.05). In contrast, the prevaccination levels of anti-PRP did not correlate significantly with the magnitude of the antibody or AbSC response and did not affect the kinetics of the AbSC. Following revaccination with PRP-D, small increases in the level of PRP antibodies (median, 2.9 micrograms/ml; n = 11) were found; no significant increase in the level of DT antibodies was seen. The numbers of PRP AbSC were lower (P = 0.04) and peaked earlier (day 7) than after the first vaccination. The isotype pattern of PRP AbSC, which was dominated by immunoglobulin A (IgA) after the first vaccination, now showed a more equal distribution between IgG and IgA AbSC. It is concluded that after immunization with PRP-D both the magnitude and the kinetics of the antipolysaccharide B-cell response are influenced by prevaccination immunity to the carrier molecule.

Adult↗
PubMed1991

Antibiotic susceptibility of invasive Haemophilus influenzae type b isolates in Denmark in 1988 and 1989.

A system for surveillance of invasive Haemophilus influenzae type b infections in Denmark yielded 135 strains isolated from blood or cerebrospinal fluid from August 1988 through December 1989. The susceptibility of the strains to 7 antibiotics was investigated by an agar dilution method. Ceftriaxone was found to be the most active drug followed by cefotaxime, ceftazidime, rifampicin, ampicillin, cefuroxime, and chloramphenicol. Except for ampicillin the MICs for the individual antibiotics were similar. Seven strains (5.2%), which all produced beta-lactamase, were resistant to ampicillin. Since H. influenzae type b meningitis in otherwise healthy individuals almost exclusively occurs in children aged 2 months to 4 years, a third generation cephalosporin such as ceftriaxone or cefotaxime may be considered the drug of choice for initial therapy of meningitis in this age group.

Ampicillin Resistance↗
PubMed1991

Haemophilus influenzae type b infections: secondary cases and recurrent disease.

Invasive Haemophilus influenzae type b infections in Denmark have not been known to lead to secondary cases, and recurrent disease has not been observed. Three case histories are presented and the literature reviewed. Secondary disease occurs more often among household contacts than among day-care contacts, which probably is due to genetic factors. The same factors might also influence the risk of contracting recurrent disease. Parents should be informed of the risk and promptly have their children medically evaluated in case of febrile illness. Epidemiological data from Denmark, however, do not provide background for the recommendation of rifampicinprophylaxis to patients with Hib-infection or their contacts.

Female↗
PubMed1990

Drug utilization in breast-feeding women. A survey in Oslo.

In a retrospective questionnaire survey of 885 women who had given birth 3-5 months before, fewer of those who were still breast-feeding at 4 months (n = 645) were using drugs than those who had stopped breast-feeding before 4 months (n = 240), during the 2 week period preceding registration. The average number of doses (Defined Daily Doses/1000 women/day) was 166 and 307, respectively, in that period. The number of doses taken was significantly associated with the use of oral contraceptive agents (p less than 0.005) and young maternal age (p less than 0.05). Most of the variation in drug use between breast-feeding and not breast-feeding mothers was probably due to the greater use of contraception by the latter. The number of drugs used per mother in the 4 month period seemed to be best predicted by her and her infant's disorders. Long-term medication in breast-feeding women included many drugs for which there is incomplete or no data about milk transfer, e.g. salbutamol, clemastine, dexchlorpheniramine, phenylpropanolamine, cromoglycate and levomepromazine. The disorders most extensively treated with drugs in this period were dyspepsia, haemorrhoids and inflammation of the breast. The finding that smoking was associated with early weaning and consumption of alcohol with prolonged breast-feeding calls for further investigation. More information on these drug and health issues to the breast-feeding mother is highly desirable.

Adult↗
PubMed1990

Carriage and antibiotic susceptibility of Haemophilus influenzae type b and non b in Danish day-care attendees.

A study of carriage of Haemophilus influenzae type b (Hib) and non b in Danish day-care facilities, employing a highly selective medium supplemented with three antibiotics and direct detection of the type b capsular antigen by latex-agglutination and coagglutination, was carried out. Of 329 children, 217 (66%) were found to be carriers of Haemophilus influenzae. Among 64 children from day-care centers in which a case of invasive Hib infection had occurred, four carriers of type b were found, whereas no type b carriers were identified among 265 children from unexposed day-care centers (p less than 0.003). Of 217 isolated strains, seven (3.2%) were found to have lowered susceptibility to ampicillin, two (0.9%) to chloramphenicol, two (0.9%) to cefuroxim, and one (0.5%) to cefotaxim.

Anti-Bacterial Agents↗
PubMed1989

[Haemophilus influenzae type b vaccines].

Haemophilus influenzae type b (Hib) causes severe invasive infections in children such as meningitis and epiglottitis. Vaccines against Hib are now available. This article describes the background for the development of these vaccines and their composition, it presents available data on immunogenicity and protective efficacy and briefly discusses the need for their use in Denmark.

Bacterial Vaccines↗
PubMed1989

[Disorders and drug consumption among infants. Does breast feeding have an impact?].

Disorders and drug use were analysed in 885 infants whose mothers responded to a questionnaire approximately four months after birth in Oslo, Norway in 1985. Breast-feeding had no influence on drug use in infants, though a lower incidence of some disorders (diarrhea, constipation, vomiting) was found in infants who were breast-fed for average four months than in infants who were weaned earlier. Use of drugs in infants was positively associated with use of drugs by the mother and with the length of her education. About 75% of the babies had at least one disorder and 60% had received at least one drug during the four month registration period. It was claimed that 85% of the drugs were recommended by a physician or a nurse. Anticolic agents, respiratory agents and dermatologicals were given frequently. The single most used drug was dimethicone. 98% of the 261 infants with colic syndrome were treated with this surface active drug, which has an efficacy similar to placebo. During a two week period preceding registration 12% of all infants and concomitantly 25% of the breast-fed infants were exposed to drugs at least once. The drug intake through breast milk was calculated to be 1/7 of the total drug use (117 infant Defined Daily Doses/1,000 infants/day) in breast-fed babies. Validation of the answers to the written questionnaire by subsequent interview of 96 mothers revealed considerable underreporting in the former; 33% for disorders, 22% for drugs and 18% for infant doses. It is concluded that medication for minor disorders in infancy is quite extensive and often unnecessary. Further informative efforts should be directed at parents, as well as the health workers involved.

Breast Feeding↗
PubMed1989

[Pulmonary arteriovenous fistula in a newborn infant with hereditary telangiectasis].

A case of pulmonary arteriovenous fistula in a newborn baby suffering from hereditary teleangiectasis is described. 15% of patients with hereditary teleangiectasis develop pulmonary arteriovenous fistulas, most of which do not cause symptoms until adult life. Children with hereditary teleangiectasis should be followed regularly, because of the risk of developing vascular malformations, the most frequent locations being the nasal mucosa, the lungs and the gastrointestinal tract.

Arteriovenous Fistula↗
PubMed1989

Haemophilus influenzae type b infections in adults.

31 cases of invasive Haemophilus influenzae type b infections occurred in adults in Denmark during a period of 2 years and 5 months corresponding to an incidence of 0.3/100,000/year. Only 6 patients had no underlying condition. The incidence of H. influenzae type b infections in adults will probably rise in the future, because the increasing use of therapeutic measures affecting the immune system will lead to an increase in the number of susceptible patients.

Adolescent↗