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Biomedical subjects

L Hagberg

Publications and source records attributed to L Hagberg.

At least 109 records · Page 6Linked to original sources
PubMed1987

Neutrophil recruitment and bacterial clearance correlated with LPS responsiveness in local gram-negative infection.

The inflammatory response to Gram-negative infection was studied in LPS responder and nonresponder C3H mice. Twenty-four hours after ascending E. coli urinary tract infection, an influx of neutrophils into the urine was observed in C3H/HeN mice (Lpsn,Lpsn); no significant neutrophil influx occurred in C3H/HeJ mice (Lpsd,Lpsd) at this time. A second peak of urinary neutrophil excretion was observed in both strains of mice approximately 6 days post-infection. The first, but not the second peak was inducible by inoculation with formalin-killed E. coli but not by Gram-positive bacteria. This finding suggested that the first peak is triggered by LPS, whereas the second peak emanates from other bacterial components which activate both LPS responder and nonresponder mice. The first peak of the inflammatory response was inversely related to bacterial clearance. C3H/HeJ mice (Lpsd,Lpsd) retained about 2000-fold more E. coli in the kidneys than C3H/HeN mice (Lpsn,Lpsn). The infection persisted despite the late-occurring influx of neutrophils in C3H/HeJ mice. These results suggest that an inflammatory response to LPS is required for the elimination of a local Gram-negative infection.

Animals↗
PubMed1987

An outbreak of diphtheria among Swedish alcoholics.

After 25 years without any indigenous cases of diphtheria in Sweden, an outbreak occurred in the city of Göteborg, during 1984 to 1986. A group of alcoholics constituted the reservoir of Corynebacterium diphtheriae. The outbreak included 13 clinical cases and 65 carriers. The death-to-case ratio and the complication rate among the clinical cases was high, with three fatal cases and six patients developing reversible paralyses. The fatal cases had no history of previous immunization. The outbreak demonstrates the necessity of a good vaccination status to diphtheria, also in countries where the disease was thought to have been eradicated.

Adolescent↗
PubMed1987

Adverse reactions and immunogenicity in adults to regular and increased dosage of diphtheria vaccine.

Booster doses of 3 Lf or 7.5 Lf of a regular diphtheria vaccine were given to 200 previously immunized adult volunteers. The toxoid was prepared from toxin with a purity of 2100 Lf/mg protein nitrogen and adsorbed to aluminium phosphate. Systemic reactions were rare and no severe symptoms were observed. Local reactions occurred in 40-50% of the vaccinees, but in only 7.5% were they of clinical significance, i.e. an area of redness/swelling greater than 5 cm. The two doses did not cause significant differences in reaction rates, and the 7.5 Lf dose elicited a better antitoxin response. Thus, a dose of 7.5 Lf diphtheria toxoid of similar purity can safely be given to adults in vaccines.

Adult↗
PubMed1987

Bacterial virulence versus host resistance in the urinary tracts of mice.

The relative contributions of host resistance and bacterial virulence were analyzed in a mouse model for ascending urinary tract infection. The congenic mouse strains C3H/HeJ and C3H/HeN were used in parallel. They differ in their reactivity to lipopolysaccharide (LPS) and susceptibility to experimental urinary tract infection. C3H/HeJ cells are susceptible to infection and are nonresponders to LPS (Lpsd Lpsd), whereas C3H/HeN cells respond to LPS and are resistant to infection (Lpsn Lpsn). The Escherichia coli pyelonephritis isolate GR-12, serotype O75K5, expressing adhesins specific for globoseries glycolipids (P fimbriae) and for mannosides (type-1 fimbriae), and its derivatives deficient in these factors were used, either singly or in combination, to establish experimental infections. In C3H/HeN mice, the relative persistence of E. coli was inversely proportional to its phagocytosis in vitro. Loss of the O75 and K5 antigens increased the tendency toward hydrophobic interaction, promoted phagocytosis, and reduced persistence in the kidneys. This was not the case in C3H/HeJ mice, in which O75- and K5- serotypes persisted in the same extent as did the parent strain. The total number of bacteria recovered from the kidneys of C3H/HeJ mice was about 1,000-fold higher than the number recovered from kidneys of C3H/HeN mice 24 h after infection. Previous studies have demonstrated a delayed influx of polymorphonuclear leukocytes into the urinary tracts of C3H/HeJ mice. The results are consistent with the hypothesis that phagocyte activation through LPS is a major defense mechanism against E. coli in the kidney, a property in which C3H/HeJ mice are deficient.

Animals↗
PubMed1987

Destructive chronic borrelia meningoencephalitis in a child untreated for 15 years.

A case of borrelia spirochetosis with recurring episodes of progressively destructive chronic meningoencephalitis, untreated for 15 years, is presented. The patient, now 23 years old, represents an example of the natural course of the disease and may serve as a reminder of the diagnosis in retrospective cases as well as prospectively for acute and chronic states of serous meningitis/meningoencephalitis both in children and adults.

Adult↗
PubMed1986

Interaction of a pyelonephritogenic Escherichia coli strain with the tissue components of the mouse urinary tract.

Immediately following the introduction of cells of a pyelonephritogenic strain of Escherichia coli (expressing both GS and MS adhesins) into the mouse bladder, these cells were found to be randomly distributed on the mucosal surfaces of both the bladder and the kidney. After 24 hr. these adherent bacterial cells had proliferated to form nonrandomly distributed adherent microcolonies on both mucosal surfaces and large masses within the renal ducts. Large amounts of amorphous material, which we presume to be of both host and bacterial origin, was associated with the bacterial microcolonies on the infected tissues. The removal of urinary slime and tissue coat material by acid pretreatment increased both the degree and the apparent avidity of bacterial adhesion to the bladder mucosa. The adherent bacteria on the bladder mucosa were radically elongated, while those on the kidney mucosa usually retained their short rod-like morphological characteristics. These data suggest that pyelonephritogenic bacteria adhere to mucosal surfaces in both the bladder and kidney, and proliferate to form adherent microcolonies within which bacteria are associated with large amounts of amorphous extracellular material.

Animals↗
PubMed1986

Antitoxin antibody levels and the outcome of illness during an outbreak of diphtheria among alcoholics.

During an outbreak of diphtheria among alcoholics in Göteborg, Sweden, a study was made of the diphtheria-antitoxin antibodies in serum samples from 8 clinical cases and 36 carriers of toxin-producing Corynebacterium diphtheriae. 33/36 carriers were antibody-positive and had antitoxin titres greater than 0.01 IU/ml, a level which is regarded as relative protective, while only 1/8 clinical cases had such a titre. This patient presented a mild illness with no complications. The results of the study of this outbreak stress the importance of maintaining adequate antibody levels against diphtheria in highly developed societies.

Alcoholism↗
PubMed1985

Genetic factors in host resistance to urinary tract infection.

In patients with recurrent pyelonephritis, the pathogenetic events proceed through intestinal colonization, spread to the urinary tract and persistence, seemingly uninterrupted by host defense mechanisms. The factors responsible for the deficient bacterial clearance from the kidneys of these patients, and the genetic control, have not been identified. The susceptibility to colonization has been linked to an increased receptivity for attaching bacteria of the uroepithelia, and to an overrepresentation of the P1 blood group phenotype. To evaluate the role of defects in host defense for the susceptibility to pyelonephritis, experimental UTI in mouse strains with known deficiencies was used. A highly significant increase in susceptibility was noted for C3H/HeJ compared to C3H/HeN mice. The bacterial recovery was inversely correlated to the mitogenic response to LPS. Back-cross analysis revealed a linkage of susceptibility to the Lpsd/Lpsd genotype. In contrast, T and B lymphocyte and complement (C5) defects had little effect on the clearance of Escherichia coli from the kidneys. It is concluded that the inflammatory mechanisms induced by LPS are essential for resistance to experimental pyelonephritis.

Animals↗
PubMed1985

Non-antibiotic prevention of urinary tract infection.

The identification of several glycoconjugates as receptors for attaching bacteria has resulted in optimism regarding the use of receptor analogues in preventing infection. The structure of receptor-active oligosaccharides and the patient groups which might benefit from such treatment are most thoroughly understood for urinary tract infections. Prevention of adhesion and delay or decrease of infection was achieved using oligosaccharides from the globoseries of glycolipids containing Gal alpha 1----4Gal. This minimal receptor structure as a free saccharide was, however, not sufficient. It was the intact P, P1 and pk determinants which showed optimal activity in vitro. In addition, protection against experimental UTI results from previous exposure to whole bacteria or isolated antigens. The mechanism(s) of protection and their relevance in clinical UTI remain to be defined.

Animals↗
PubMed1985

Evidence for separate genetic defects in C3H/HeJ and C3HeB/FeJ mice, that affect susceptibility to gram-negative infections.

Past studies have suggested a linkage between susceptibility to Salmonella typhimurium infection and the Lpsd genotype in C3H mice. Recently, this linkage was questioned by the finding that C3HeB/FeJ mice (Lpsn,Lpsn) were highly susceptible to systemic S. typhimurium infection. The present study shows a marked difference between C3H/HeJ and C3HeB/FeJ in their susceptibility to Gram-negative urinary tract infection. The number of E. coli and S. typhimurium recovered from the kidneys 24 hr after infection was 70 to 100 times higher in C3H/HeJ than in C3HeB/FeJ or C3H/HeN mice. Subsequently, in C3HeB/FeJ mice S. typhimurium multiplied to the level of C3H/HeJ mice, resulting in a shorter mean survival time of C3H/HeJ and C3HeB/FeJ compared with C3H/HeN mice. In contrast, E. coli remained localized to the urinary tract of C3H/HeJ mice but were eliminated from C3HeB/FeJ and C3H/HeN mice. Thus, experimental E. coli urinary tract infection appears to provide a method to differentiate the genetic defects of C3H/HeJ and C3HeB/FeJ mice. The results support an influence of the Lpsd genotype on clearance of Gram-negative bacteria from the kidneys of C3H mice.

Animals↗
PubMed1984

Difference in susceptibility to gram-negative urinary tract infection between C3H/HeJ and C3H/HeN mice.

The difference in susceptibility to urinary tract infection between C3H/HeJ and C3H/HeN mice was tested for with gram-negative strains differing in lipopolysaccharide composition. Recently, impaired clearance of Escherichia coli from the kidney of C3H/HeJ compared to C3H/HeN mice was shown to be correlated with the LPS low responsiveness. In this study, a difference in clearance from the kidneys of C3H/HeJ and C3H/HeN mice was found only with lipopolysaccharide-containing bacteria. Gram-positive bacteria, e.g., Staphylococcus saprophyticus and Streptococcus agalactiae, were recovered in essentially equal numbers from the kidneys of mice of both strains. In contrast, of the lipopolysaccharide-containing strains used, all persisted in higher numbers in the kidneys of C3H/HeJ mice than in the kidneys of C3H/HeN mice. Variations in the O side chain did not eliminate this difference. E. coli Hu734 O75+K5+ and the rfb- mutant O75-K5+ remained in similar numbers in C3H/HeJ mice, although O75-K5+ was eliminated more rapidly in C3H/HeN mice. The core structure did not affect the differential persistence in the two mouse strains. The rfb mutants with R1-R4 cores were eliminated after 24 h from the C3H/HeN mice, but remained in significant numbers in the kidneys of C3H/HeJ mice. Even the Re mutant of Salmonella minnesota persisted in low numbers in C3H/HeJ mice. The relative bacterial recovery from either mouse strain was related to the overall virulence of the infecting bacterial strain, but the difference between C3H/HeJ and C3H/HeN mice was associated with responsiveness to parts of lipopolysaccharide common to the bacterial strains tested.

Animals↗
PubMed1984

Wrist flexion strength after excision of the pisiform bone.

Diseases of the pisiform triquetral (P-T) joint and the pisiform itself are often treated with excision of the pisiform bone. The flexor carpi ulnaris (FCU) tendon inserts on the volar aspect of the pisiform, suggesting a loss of strength in wrist flexion following excision of the bone. Isometric and dynamic, isokinetical measurements were made using a strain-gauge dynamometer (Cybex II). Slight postoperative reduction of wrist flexion strength, compared with the contralateral wrist, was noted but not of clinical significance. It is concluded that one should not refrain from excision of the pisiform bone for fear of considerable strength loss in wrist joint flexion.

Aged↗
PubMed1983

Contribution of adhesion to bacterial persistence in the mouse urinary tract.

The affinity of uropathogenic Escherichia coli to kidneys and bladders of experimentally infected mice was shown to be determined in part by the adhesive properties of the infecting bacteria. Mice were infected with various pairwise combinations of two homogeneic sets of bacteria: (i) mutants derived from a human pyelonephritis E. coli isolate which were selected to express either or both adhesins specific for globoseries glycolipid receptors or for "mannosides"; and (ii) transformants of a normal fecal isolate which harbored recombinant plasmids encoding the genes for one or the other adhesin or which harbored only the vector plasmid. The relative efficiency of survival of the strains to be compared was evaluated in each animal by plating on selective media of samples of homogenized kidneys and bladders taken 24 h after intravesical inoculation. The presence of adhesins specific for globoseries glycolipid receptors, which mediate the in vitro mannose-resistant attachment to human and mouse uroepithelial cells, enhanced bacterial recovery from both kidneys and bladders of infected animals. The addition to the infecting strain of adhesins binding mannoside residues further improved bacterial recovery from the bladder, but not from the kidney. The mutants and transformants with adhesins binding only mannosides were recovered in higher numbers from the bladder than those expressing adhesins specific for the globoseries glycolipids only. There was apparent selection in vivo decreasing expression of mannoside binding adhesins in the kidneys, but not in the bladders, of animals infected with the mutant expressing both types of adhesins. Regardless of adhesive properties, the mutants of the pyelonephritis isolate were recovered in significantly higher numbers than the fecal isolate with adhesins encoded on recombinant plasmids. We conclude that the adhesive properties in part determine the localization and retention of bacteria in the mouse urinary tract. However, the addition of adhesins to a commensal E. coli strain was not sufficient to confer colonization capacity comparable to that of a pyelonephritis strain.

Adhesins, Escherichia coli↗