PubMed Health⌕ Search

Biomedical subjects

P Christensen

Publications and source records attributed to P Christensen.

At least 19 recordsLinked to original sources
PubMed1979

The relationship of urinary prostaglandins and plasma renin to sodium balance and diuresis in normal man.

The significance of changes in sodium balance and urinary sodium excretion for renal PG excretion was studied in normal man. In protocol B a strongly negative sodium balance was produced in 5 healthy young subjects by a low sodium diet given for 7 days (lo mmol Na/day) with 80 mg furosemide p.o. added on the last two days. 24 hour urinary PGE2 excretion remained constant, while plasma renin increased. In protocol A the effect of i.v. furosemide (1 mg/kg bwt) on urinary PGE2 and PGF2 alpha excretion rates was examined in 5 healthy young subjects. Rapid but short-lasting increases in PG excretion rates ran in parallel with the changes in urine flow rate. The study suggests that PGE2 is not of importance for the sodium homeostasis in normal man. Renal prostaglandins may play a modifying role for the renal response to loop diuretics but are hardly instrumental for the diuretic effect.

Adult↗
PubMed1979

Sodium balance, urinary prostaglandin E2 and renin in normal man.

1. Urinary prostaglandin (PG) E2 excretion and plasma renin were measured in five healthy volunteer subjects for 2 h after intravenous injection of frusemid (protocol A) and during salt restriction for 7 days with frusemide added on the 2 last days (protocol B). 2 In protocol A, peak values in PGE2 and urine flow were reached in 10-20 min, after which the values rapidly subsided. Plasma renin increased twofold in 60 min. 3. In protocol B, even during severe antinatriuresis (day 5) and during maximal negative sodium balance (day 7), no change in urinary PGE2 excretion was observed. Plasma renin increased twofold on day 5 and increased tenfold on day 7. 4. The result of protocol B does not suggest any essential role of renal PGE2 for sodium excretion or sodium homeostasis in man. The result of protocol A may point to a role of renal prostaglandins for the diuretic action of frusemide.

Adult↗
PubMed1979

On the pathogenetic role of prostaglandins in Bartter's syndrome.

Two patients, one with Bartter's syndrome and one with severe abuse of diuretics, were investigated before and after indomethacin treatment. Before indomethacin the two patients showed a similar pattern of hypokalaemic alcalosis, secondary hyperaldosteronism, and increased urinary excretion of PGE2 and kallikrein. After a few days on peroral indomethacin medication the hypokalaemia was significantly improved, the plasma renin activity, and the urinary excretion of aldosterone, PGE2 and kallikrein were normalized in both patients. It is concluded that the beneficial effect of indomethacin cannot be used as a proof of prostaglandin overproduction as the primary defect in Bartter's syndrome.

Adolescent↗
PubMed1979

Upper respiratory tract spread of group B streptococci type I b in a kindergarten.

In a kindergarten with 42 children and 17 female staff members, an epidemic of group B streptococcal carriage in the upper respiratory tract occurred. In the middle of February 1978, 6 children and 5 adults carried type I b streptococci in the throat while only 2 of these 11 were carriers 2 weeks later. Only one other streptococcus, belonging to type II, was found in the throat specimens. Five strains other than type I b were found in the urogenital tract of the staff. Three type I b throat carriers were also urogenital carriers of this type. The spread of type I b streptococci could have resulted from co-spreading with other upper respiratory tract pathogens found, including group A streptococci of type 12. Haemophilus influenzae, Branhamella catarrhalis and pneumococci. Estimation of antibodies with radiolabelled protein A indicated an immune response to type I b, but not to types I a, II or III group B streptococci in the staff compared with healthy blood donors.

Adolescent↗
PubMed1979

Precipitation of streptococcal peptidoglycan by human sera: influence of anti-immunoglobulins.

Antibodies to streptococcal peptidoglycan (PG) were detected by gel-precipitation in 38% of sera from blood donors and in 71% of sera with a Waaler-Rose test titre of greater than or equal to 1:64. Twenty-six rheumatoid arthritis sera revealed patterns of interference with complete or partial fusion between PG and aggregated human IgG while none of the sera precipitating both these preparations showed non-interference. The reactions were interpreted as denoting interference between the PG-antibody complexes and aggregated IgG. Conversion of some non-precipitating blood donor sera to PG precipitation was obtained by addition of isolated rheumatoid factor, in itself not precipitating PG, to the sera. Thus, the high frequency of PG precipitation among rheumatoid arthritis sera could--at least in part--be attributed to the participation of anti-IgG in the reaction.

Antibodies, Anti-Idiotypic↗
PubMed1979

Interaction of the Fc part of IgG with Lancefield extracts of hemolytic streptococci. Strain specificity and activity.

Lancefield extracts of 19 types of group A streptococci as well as one group C and one group G strain were examined for agglutination of human red cells coated with various anti-Rh antibodies. Fourteen extracts agglutinated one or more of the coated cell samples, while five did not. The agglutination was inhibited by Fc but not by Fab fragments of human IgG. After mouse passages, three of the non-agglutinating strains acquired agglutinating capacity. At least three different reactivities were distinguished by the action of the extracts on IgG1 and IgG3 coated cells, respectively. Two of the streptococcal extracts, agglutinating the same anti-Rh coated cells, could be further differentiated in hemagglutination inhibition (HAI) experiments using purified IgG3 myeloma proteins. Five selected agglutinating systems were inhibited by purified myeloma proteins of the IgG1, IgG2, and IgG4 subclasses. IgG3 proteins inhibited only two of the five HAI systems.

Antibodies, Bacterial↗
PubMed1979

Demonstration of the non-identity between the Fc receptor for human IgG from group A streptococci type 15 and M protein, peptidoglycan and the group specific carbohydrate.

After electrophoresis of an alkaline extract of type 15 group A streptococci, three main precipitation lines were obtained in diffusion experiments against commercial human polyclonal IgG (lines 1, 2 and 3). Nineteen of 23 sera (83%) from apparently healthy human individuals gave line 3, while 6 of them (26%) gave line 1. The sera giving line 1 did also give line 3. Line 2 was obtained with 2 sera only, also giving lines 1 and 3. Line 3 was caused by a streptococcal Fc-receptor for human IgG, since the line could be displaced by addition of Fc-fragments, but not Fab-fragments of pooled human IgG. Line 1 was shown to be different from line 3, since (1) line 1 was suppressed in contrast to line 3 on absorption of a human serum or commercial polyclonal human IgG with S. aureus; and (2), line 1 was suppressed by Fab-fragments but not Fc-fragments of polyclonal human IgG. Line 2 could be inhibited by addition of peptidoglycan to commercial polyclonal human IgG or a human serum investigated. Another line, 4, obtained in diffusion experiments involving electrophoretically separated alkaline extract of type 15 group A streptococci was type-specific as shown by rabbit antisera to streptococci type M1, M8, M15, and T44, and disappeared on trypsinization of the extract. The component responsible for line 4 in the streptococcal extract, judged to be type-specific M protein, had a mobility different from the component responsible for line 3 in electrophoresis.

Bacterial Proteins↗
PubMed1978

Quantitation of protein adsorbance to glass and plastics: investigation of a new tube with low adherence.

Four different tubes were tested for adherence of human albumin, aggregated and non-aggregated human IgG and rabbit IgG: glass, polystyrene and cellulose nitrate tubes, and a new plastic tube, Minisorp. From the viewpoint of low protein adherence, the new tube was superior to the others, in the following test situation: (i) low concentration of proteins; (ii) 0.9% NaCl used as diluent; and (iii) when detergents in the tests are undesirable.

Adsorption↗
PubMed1978

Binding of aggregated IgG in the presence of fresh serum by group A streptococci producing pharyngeal infection: possible connection with types frequently involved in acute nephritis.

109 streptococcal strains, belonging to diverse serological groups and types, were investigated as regards their capacity to bind IgG aggregates in the presence of fresh serum. Strains capable of such binding were not found in groups B,C,D,E,G,L,M or N. Such binding was restricted to a few types of group A streptococci: the potentially nephritogenic types 2, 6 and 12, and four strains belonging to type M 39, M 46 and M 22 or M 62, the nephritogenic capacity of which is unknown. Two of five strains isolated from patients with acute post-stretococcal glomerulonephritis (AGN) and 19/28 type T 12, SOR-strains, isolated during an epidemic in a kindergarten with associated cases of AGN, were found to bind aggregates. The findings suggest a possible association between capacity to bind aggregates in the presence of serum and the serological types of group A streptococci involved in acute nephritis following pharyngeal infection.

Acute Disease↗
PubMed1978

Typing of group B streptococci from the throat and urogenital tract of females.

Group B streptococci were isolated from the urogenital tract of 54 of 168 patients (32%) examined at a gynecological outpatient department. 11 (7%) of the patients were group B throat carriers. In contrast to the frequency of type III group B steptococci in the urogenital tract (41% of group B streptococcal carriers) only 1 of 11 strains isolated from the throat belonged to type III. Apart from 1 patient who carried type III streptococci in the urogenital tract, all patients who were both throat and urogenital tract carriers harboured the same type in both sites. Significantly more patients who were only throat carriers of group B streptococci or harboured another type in the throat than in the urogenital tract, harboured lactose-fermenting group B streptococci as compared to patients who were only carriers of group B streptococci in the urogenital tract. These results pointed out the possible existence of "throat-preferring" and "urogenital-preferring" group B streptococci.

Adolescent↗
PubMed1978

Rectal colonization with group B streptococci: relation to urogenital carriage.

Urethral, cervical and rectal specimens were taken from 92 females and urethral and rectal swabs from 46 males attending a venereological outpatient department. The frequencies of group B streptococci were, in the women: urethra 24%, cervix 14% and rectum 17%; in the males: urethra 22% and rectum 7%. These findings, supported by the results of serotyping, clearly demonstrate that the human urethra is an important site of colonization and do not support the idea that the gastrointestinal canal is the primary site of acquisition.

Adolescent↗
PubMed1978

[Diagnosis of primary hyperparathyroidism based on determination of parathormone in venous blood of the neck (author's transl)].

Experiences with 77 patients with primary hyperparathyroidism (HPT) are reported. Among the diagnostic parameters, the serum calcium level is the most significant; a definite diagnosis can be made through PTH-RIA. The problem of HPT diagnosis are discussed. For standardization, our own human PTH preparation, produced from tissue culture of operatively removed human adenoma of the parathyroid gland, has been used. For determination of parathormone, venous blood should be selectively extracted from the neck before every relapse-necessitated operation. The technically expensive and difficult examination methods do not excuse the surgeon from carefully exploring all of the parathyroid glands, though the general procedures to be applied before the first operation are still disputed.

Antigen-Antibody Complex↗