[Does sealing the oval window in addition to the round window bring an advantage in reserve therapy of acute idiopathic deafness?]

BACKGROUND

Following sudden unilateral deafness or severe sensorineural hearing loss, patients with unsuccessful intravenous steroid therapy can be treated with explorative tympanotomy with sealing of the round (RW) and/or oval window (OW), due to suspected rupture of the RW with perilymph fistula (PLF) or a fissula ante fenestram (FAF). This study investigated whether additional sealing of the oval window (RW+OW) achieved an improved hearing benefit as compared to sealing of the round window only (RW) .

METHODS

This retrospective study investigated 54 patients with acute profound hearing loss who underwent tympanoscopy. Audiometric examinations were performed preoperatively and at two postoperative intervals (1 month and 3-6 months after surgery). In 28 patients, the OW was sealed in addition to the RW.

RESULTS

No intraoperatively visible PLF or FAF were reported. Hearing thresholds were significantly reduced in the early postoperative follow-up period and further improvement was observed 3-6 months later. No significant differences between the RW and RW+OW subgroups were seen at either follow-up timepoint. In 65% (Kanzaki criteria) and 74% (Siegel criteria) of patients, partial or complete postoperative hearing improvement was observed. Upon comparing the groups of patients with and without hearing improvement, no statistical significance was found in terms of gender, age, secondary diagnoses, or latency period between symptom onset and surgery.

CONCLUSION

Additional sealing of the OW did not lead to significantly better postoperative hearing thresholds. In general, postoperative hearing improvement corresponds to published spontaneous remission rates.

Bone morphogenetic protein 2/SMAD signalling in human ligamentocytes of degenerated and aged anterior cruciate ligaments

OBJECTIVE

Anterior cruciate ligament (ACL) degeneration leads to knee instability and favors osteoarthritis (OA) progression. During ageing the growth factor sensitivity of ligaments changes but nothing is known about BMP2-signalling and -sensitivity in degenerated ACLs. This study addressed the question whether a dysregulated BMP2 signalling might contribute to age- and OA-dependent ACL degeneration.

METHOD

ACL samples from patients with/without OA of different ages (<60 and ≥60 years, males, females) were graded histopathologically (n = 45). After stimulation of cultured ACL fibroblasts with 5 nM BMP2 for different time points, phosphorylation of SMAD1/5/8 and gene expression of crucial BMP2 signalling proteins, ligamentogenic and chondrogenic transcription factors, scleraxis (SCX) and SOX9, were analyzed.

RESULTS

ACL samples displayed different grades of degeneration, often associated with synovitis and calcium deposits. Degeneration correlated significantly with synovitis. ACL fibroblasts expressed BMP type I receptors ALK3 and ALK6 and the BMP type II receptor BMPRII. Donors could be divided into "responders" and "non responders" since their BMP2 mediated SMAD1/5/8 phosphorylation level differed. Basal ID1 expression was lower in cells derived from OA compared with non-OA patients and BMP2 led to an ID1 induction in both. Irrespective of BMP2 stimulation, the donor age significantly influenced the expression profile of BMP6 and SCX but not BMP signalling. The BMP2-mediated SMAD6 expression differed between OA and healthy ACL fibroblasts.

CONCLUSION

Our data indicate that the expression level of BMP2/SMAD target genes such as ID1 and SMAD6 was reduced in ACL fibroblasts derived from OA compared with non OA patients.

Comparison of seven commercial enzyme-linked immunosorbent assays for the detection of anti-diphtheria toxin antibodies

Determination of immune status of patients to diphtheria toxin is based mainly on the results of commercially available ELISA kits. The aim of the present study was to compare the results obtained by ELISAs from seven different manufacturers: Mikrogen, Immunolab, Sekisui Virotech, NovaTec, Virion\Serion, IBL International and Euroimmun. All assays were performed according to the manufacturers' instructions. The concentrations of the anti-diphtheria toxin antibodies in 72 serum samples were calculated on the basis of curves constructed from standards supplied by manufacturers and the new reference material-International Standard for Diphtheria Antitoxin (10/262). The repeatability and reproducibility of all the ELISA kits tested were good. Number of sera with concentrations of the anti-diphtheria toxin antibodies below the WHO-recommended level of protection (0.1 IU/ml) were dependent on the ELISA used: Mikrogen, 20/72 samples (27.7%); Immunolab, 11/72 samples (15.3%); Sekisui Virotech, 0/72 samples (0%); NovaTec 18/72 samples (25.0%); Serion 12/72 samples (16.7%); IBL International, 7/72 samples (9.7 %); and Euroimmun, 17/72 samples (23.6%). However, the results obtained in particular ELISAs, with the exception of Sekisui Virotech, were much more consistent when the concentrations of the anti-diphtheria toxin antibodies in 72 sera measured by using curves constructed from the International Standard 10/262. The data obtained clearly demonstrated that manufacturer-dependent differences between anti-diphtheria IgG ELISA kits exist. The differences in recommendations accepted by the individual manufacturers together with differences shown in our studies in sensitivity greatly affect the clinical interpretation of results.

[Use of recombinant P1 protein of Mycoplasma pneumoniae for the serodiagnosis of mycoplasmosis]

INTRODUCTION

Mycoplasma pneumoniae is a common etiologic agent of community-acquired respiratory infection. In serological diagnosis of M. pneumoniae infections tests have been described based on the purified P1 protein, which is the most important virulence factor of this pathogen, as antigen. The aim of his study was to express and purify a recombinant protein P1 M. pneumoniae and next evaluate this protein as high specific antigen in serodiagnosis of mycoplasmosis.

METHODS

Protein P1 M pneumoniae was expressing in E. coli BL21 (DE3) using the pET-30 Ek/LIC expression vector. Based on published literature, we decided to express C-terminal region [P1-C1] encompassing amino acid residues 1160 to 1521. Purification was accomplished by immobilized metal (Ni2+) affinity column chromatography (His-trap). Serum samples collected from 221 patients with mycoplasmosis, positive in complement fixation test (CFT), 87 patients with other then mycoplasmosis bacterial infections and 80 blood donors were screened for anti-P1 recombinant protein IgA, IgG and IgM antibodies by using the home-made ELISA.

RESULTS

SDS-PAGE and Coomassie brilliant blue staining confirmed a high purity of the recombinant P1 protein preparation with an expected molecular mass of 39,7 kDa. The specificity of the recombinant protein was confirmed by western blot analysis using serum samples from rabbits immunized by M pneumoniae. The results of ELISA revealed that more then 70.0% of patients with mycoplasmosis confirmed by CFT, had antibodies to recombinant P1 protein in diagnostically significant level (x + 2SD). The antibodies were found only sporadically in sera obtained from patients with other then mycoplasmosis bacterial infections and clinically healthy persons. A comparison of results obtained in home-made ELISA with results of commercial western blot (Virotech) showed similar, ranged from 84.2% to 97.4%, compatible of results. The IgM antibodies to recombinant P1 protein were found in 87.2% sera obtained in acute phase of disease, in 80.0% sera obtained 2-4 weeks after onset of clinical symptoms and only in 43.8% sera obtained in chronic mycoplasmosis.

CONCLUSIONS

The present study confirmed the earlier observations of the high usefulness of recombinant P1 protein for reliable serologic diagnosis of M. pneumoniae infection.

The presence of the ail gene in clinical strains of Yersinia enterocolitica isolated from stools in Poland and characteristics of gene variant

The non-American variant of ail gene was found independently of the virulence-associated plasmid pYV in all 152 tested clinical Y. enterocolitica O:3 strains isolated from humans in Poland. Data obtained by sequencing exhibited high genetic stability of the ail gene present in the tested isolates obtained from different regions of the country. The PCR-RFLP technique was sufficient for fast identification and characterization of the ail gene variant present in the tested strains.

[Use of PCR methods for detection of selected genes of Mycoplasma pneumoniae]

The aim of this study was standardization of PCR for the detection of gene encoding the P1 protein, 16S rRNA and elongation factor Tu of M. pneumoniae. A total of 13 strains of M. pneumoniae, 28 strains of other mycoplasmas and 14 strains of different bacteria causing respiratory tract infections were tested. In all of tested M. pneumoniae strains the presence of the sought genes was confirmed. The specificity of DNA was confirmed by the restriction endonuclease analysis with enzymes Hind III, Alu I and Hha I. With none of primers specific for the M. pneumoniae genes amplification of DNA from other bacteria was noted. The PCR method with the selected primers allowed to detect from 10(2) to 10(4) cfu M. pneumoniae/ml suspended in broth. The obtained results indicate that the PCR method can be used for detection of M. pneumoniae genes. A very good sensitivity and specificity predestine++ PCR as a potential quick diagnostic method for identification of M. pneumoniae in clinical specimens.

[Evaluation of the usefulness for the latex agglutination test for serodiagnosis of Mycoplasma pneumoniae infections]

The usefulness of latex agglutination test prepared in our laboratory for the diagnosis of M. pneumoniae infections was assessed. A total of 628 serum samples obtained from patients with respiratory tract infections were tested by complement fixation test and by latex test, from among them 274 serum samples were additionally tested by ELISA--Ig A/--IgG/--IgM and by immunoelectroprecipitation test. The highest sensitivity and specificity was displayed by the latex test in relation to ELISA when determining mycoplasmal antibodies of IgM class (respectively 82.1% and 89.6%) and to the complement fixation test (81.0% and 89.0%). Positive latex test results in our investigations were associated only with the presence of IgM antibodies and were not dependent on the IgA and IgG antibody classes. The latex agglutination test may be used in routine serodiagnosis of mycoplasmosis under condition that the results obtained in this test will be confirmed by the complement fixation test or ELISA.

[Evaluation of the usefulness of commercial enzyme-linked immunosorbent assays for diagnosis of Mycoplasma pneumoniae infections]

The usefulness of the ELISA distributed by BioChem ImmunoSystems, Medial Polska, Biomedica/Virotech and prepared in our laboratory (ELISA FH-K) for diagnosis of the M. pneumoniae infections was estimated. Eighty six serum samples obtained from 86 patients with respiratory tract infections were simultaneously tested by ELISA-IgM/-IgG and by complement fixation test which was accepted as a reference test. The highest sensitivity in relation to the CFT was displayed by the ELISA BioChem ImmunoSystems and Medial Polska (100%), slightly lower sensitivity by the ELISA Biomedica/Virotech--96.5% and ELISA FH-K--90.9% when determining mycoplasmal antibodies of IgM. The lowest sensitivity was displayed by the ELISA Biomedica/Virotech when determining antibodies of the IgG class (54.9%). The specificity of ELISA in relation to the CFT was generally higher when detecting mycoplasmal antibodies of the IgM class then of IgG class. The study demonstrated that all 4 ELISA may be used in routine serodiagnosis of M. pneumoniae infection. For the improve of sensitivity of ELISA it's recommended to measure simultaneously the level of mycoplasmal antibodies of IgM and IgG.

[Susceptibility to selected antibiotics of Yersinia enterocolitica 03 strains, carrying and not carrying plasmid pYV]

A total of 199 clinical strains of Yersinia enterocolitica serotype O3, biotype 4 were tested for their susceptibility to antibiotics (158 strains carried the virulence plasmid pYV and 41 strains did not). 114 isolates were tested by standard disk diffusion method for 21 antibiotics. Almost all tested strains were resistant to ampicillin and cefazolin and susceptible to amoxycillin/clavulanate, cefaclor, cefamandole, cefuroxime, cefotaxime, ceftriaxone, aztreonam, imipenem, gentamicin, amikacin, netilmicin, tetracycline, doxycycline, chloramphenicol, ciprofloxacin, sulphamethoxazole, co-trimoxazole, trimethoprim and furazolidone. In addition minimal inhibitory concentrations (MICs) of 15 antibiotics were determined by agar dilution method for all 199 strains (158 plasmid positive and 41 strains plasmid negative). Third-generation cephalosporins such as cefotaxime and ceftriaxone and a fluoroquinolone (ciprofloxacin) were the most active antimicrobial agents, tested followed by aztreonam, imipenem, trimethoprim, tetracycline, gentamicin, chloramphenicol, amoxycillin/clavulanate, cefaclor, cefuroxime, amikacin, furazolidone and sulphamethoxazole. The present study demonstrated a high susceptibility of clinical strains of Y. enterocolitica to most of the tested antibiotics. In general, there was no significant difference between susceptibility of virulence plasmid pYV positive and virulence plasmid negative strains to antibacterial agents.

Susceptibility of Polish clinical strains of Yersinia enterocolitica serotype O3 to antibiotics

A total of 199 clinical strains of Yersinia enterocolitica serotype O3, biotype 4 were tested for their susceptibility to antibiotics (158 strains carried the virulence plasmid pYV and 41 strains did not). A total of 114 isolates were tested by a standard disk diffusion method for 21 antibiotics. Almost all strains tested were resistant to ampicillin and cefazolin and susceptible to amoxycillin/clavulanate, cefaclor, cefamandole, cefuroxime, cefotaxime, ceftriaxone, aztreonam, imipenem, gentamicin, amikacin, netilmicin, tetracycline, doxycycline, chloramphenicol, ciprofloxacin, sulphamethoxazole, trimethoprim, co-trimoxazole and furazolidone. In addition, minimal inhibitory concentrations of 15 antibiotics were determined by the agar dilution method for all 199 strains (158 carrying plasmid pYV and 41 strains that did not). Third-generation cephalosporins such as cefotaxime and ceftriaxone and a fluoroquinolone (ciprofloxacin) were the most active antimicrobial agents tested followed by aztreonam, imipenem, trimethoprim, tetracycline, gentamicin, chloramphenicol, amoxycillin/clavulanate, cefaclor, cefuroxime, amikacin, furazolidone and sulphamethoxazole. The present study demonstrated a high susceptibility of clinical strains of Y. enterocolitica to most of the tested antibiotics. In general there was no significant difference between susceptibility to antibacterial agents of strains with or without plasmid pYV.

[Electrophoretic and immunologic comparative analysis of Mycoplasma pneumoniae and Mycoplasma genitalium proteins]

The Mycoplasma pneumoniae FH strain routinely used in our laboratory for over 25 years as antigen in serological tests, 2 reference M. pneumoniae strains from ATCC (29342 and M129) and 3 isolates of M. pneumoniae obtained in 1995 from pneumonia patients were compared by SDS-PAGE, complement fixation test (CFT) and by Western-immunoblotting against human and rabbit serum samples with high level of mycoplasmal antibodies. On SDS-PAGE all M. pneumoniae strains showed the same number of 23 polypeptides on the gel with identical molecular weights. The same strains on immunoblotting against human and rabbit serum samples showed six bands: 170, 89, 75, 55, 38 and 33 kDa with the strongest antibody staining in 170-(P1 protein) and 89-kDa bands. Because of its known antigenic relationships Mycoplasma genitalium was used for comparison. The pattern of M. genitalium proteins on SDS-PAGE was similar to pattern of M. pneumoniae but distinguishable. On immunoblotting six proteins of M. genitalium (135, 127, 110, 95, 75 and 45 kDa) reacted with human and rabbits immunoglobulins for M. pneumoniae antigens. Furthermore in complement fixation test both antigens, prepared from M. pneumoniae and M. genitalium, reacted as well with human and rabbit immunoglobulins for M. pneumoniae and with rabbit immunoglobulins for M. genitalium. These cross-reactions observed in serological techniques could give false positive results in routine diagnosis of M. pneumoniae infections. In such situations showing on immunoblott of presence in tested serum sample of antibodies to 170- and 89 kDa proteins could confirm M. pneumoniae infection.

Epidemiology of Mycoplasma pneumoniae infections in Poland : 28 years of surveillance in Warsaw 1970-1997

Mycoplasma pneumoniae is a common cause of lower respiratory tract disease in humans, particularly among older children, adolescents, and young adults. Infections are endemic in cities and epidemic increases are observed at intervals of 4 to 7 years. M. p

[Evaluation of the usefulness of the agglutination test with Mangifera indica extract for the identification of pathogenic Yersinia enterocolitica strains]

The study was performed on 137 Y. enterocolitica strains belonging to various serological groups, including 75 03 group strains isolated form human clinical material. The agglutination test on slides was carried out on this strains using Mangifera indica extract of own production. Agglutinating preparation obtained from the seeds of M. indica agglutinated Y. enterocolitica organisms possessing the pVY plasmid and CRMOX+ phenotype in dilutions to 1.56 micrograms/ml. In identification tests conducted parallelly agglutination solution was used in concentrations of 100 and 10 micrograms/ml. All clones of Y. enterocolitica from O3 group from cultures at 37 degrees C and with CRMOX+ phenotype possessing the pVY plasmid were agglutinated by the extract. Agglutination failed to develop in the cultures of these clones incubated at 25 degrees C. Yersinia clones not containing the pVY plasmid with CRMOX- phenotype were resistant to agglutination. The virulence plasmid was found in 44 out of 75 strains of Y. enterocolitica O3 and was identified by restriction analysis after plasmid DNA digestion with Eco RI enzyme. The obtained results agreed with those of Wauters et al. in 1995 and confirmed the opinion of these authors on the usefulness of the test with M. indica agglutinin for the identification of virulent Y. enterocolitica strains.

Occurrence of serologically verified Mycoplasma pneumoniae infections in Poland in 1970-1995

This study analyses the numbers of serologically verified Mycoplasma pneumoniae infections in Poland in 1970-1995. The investigations were performed using the complement fixation test (CFT) with sonicated antigen in National Institute of Hygiene in Warsaw and since 1985 in 33 laboratories throughout the country. The result was accepted as positive when antibody titre was 60 or higher, or at least a four-fold increase in titre occurred during the illness. During these studies five epidemics of mycoplasmosis were noted in Poland. They occurred regularly every 5 years during the autumn-winter season in 1970/1971, 1975/1976, 1980/1981 and 1985/1986. The last epidemic, which started in 1991 and culminated in 1992-1993, seems to have inaugurated a change from epidemic to endemic occurrence of M. pneumoniae infection in Poland. At the peak of the epidemic, depending on the region of country, in 20-38% of patients with respiratory tract infection serological confirmation of mycoplasmosis was obtained.

[Evaluation of the reliability of serological diagnostic tests for Mycoplasma pneumoniae infection carried out by laboratories in sanitary epidemiological stations (WSSE)]

In the action undertaken for evaluating of the reliability of serological tests for M. pneumoniae infection 33 laboratories of the Sanitary Epidemiological Stations participated. Every laboratory had to determine twice at an interval of 2-4 weeks the level of mycoplasma antibodies by the complement fixation test in serum samples divided into 4 groups: sera not containing these antibodies-titre < 5, or containing them in titres of 60, 120 and 320. The correct results of the determinations were obtained in 27 laboratories (81.8%) for samples without M. pneumoniae antibodies, and in 22 (66.6%) and 14 (42.4%) for samples with titres of 60 and 120, and 320 respectively. Only 4 laboratories (12.1%) obtained correct results of these determinations for every sample and in both testing series. In these series considered separately correct results were obtained in 9 (27.3%) and 8 (24.2%) laboratories. Faulty results in all samples in both testing series were reported from 2 (6.1%) laboratories. In the individual series all false results were obtained in 4 (12.1%) and 3 (9.1%) laboratories. The study showed that for raising of the quality and reliability level of serological investigations for M. pneumoniae infection a permanent practice should be periodic training of laboratory workers and frequently repeated interlaboratory controls of the reliability of test results.

Enzyme-linked immunosorbent assay, complement fixation test and immunoelectroprecipitation test in the diagnosis of Mycoplasma pneumoniae infections--comparative analysis

Agreement of the results of determining antibodies against M. pneumoniae was evaluated by ELISA, complement fixation test (CFT) and immunoelectroprecipitation test (IEPT) in serum samples from 685 persons including 571 patients with respiratory tract infections and 114 clinically healthy subjects. Assuming the CF test to be the reference test, a very high correlation exceeding 0.95 was found, on the basis of the calculated correlation coefficient, between the results of the CF and IEP tests and the CFT and ELISA for all immunoglobulin classes. The highest sensitivity (92.3%) was displayed by the ELISA in relation to the CF test when determining mycoplasmal antibodies of Ig M and Ig A+G+M classes and a slightly lower sensitivity by the IEPT and ELISA when determining Ig G (83% and 82.1%, respectively). The lowest sensitivity was displayed by the ELISA when determining mycoplasmal antibodies of the Ig A class (53.4%). The specificity of both tests was high and exceeded 92%. The highest agreement of CFT and ELISA was obtained when detecting mycoplasmal antibodies in a diagnostically significant titre in the M and A+G+M immunoglobulin classes (> 92%) while the lowest agreement, although statistically significant, was obtained when detecting Ig A antibodies (74.7%).

[Occurrence of virulent plasmids in strains of Yersinia obtained from various sources]

By the method of alkaline lysis the occurrence was studied of plasmid DNA in 122 strains of Yersinia. In 29 strains a single plasmid was found with characteristic growth of the organism on CRMOX (CRMOX+) medium. These features are encoded by genes located on the pYV virulence plasmid. The group of Yersinia strains possessing the virulence plasmid included 27 strains of Y. enterocolitica 0:3 isolated from clinical materials, among them 21 strains isolated from patients between January and September 1996, while the remaining two strains with the virulence plasmid belonged to Y. pseudotuberculosis antigenic group I. Following restriction analysis with the EcoRI enzyme of the virulence plasmids isolated from 27 strains of Y. enterocolitica 0:3 occurrence of only one restriction endonuclease pattern agreeing with the virulence plasmid pattern of Y. enterocolitica 0:3 strains reported in the literature was found in all strains. On the other hand, the restriction analysis of the virulence plasmids obtained from Y. enterocolitica 0:3 and Y. pseudotuberculosis I strains showed evident differences between these plasmids in the size of the particle and the restriction pattern. The plasmid size calculated on the basis of the analysis of the restriction endonuclease patterns for virulence plasmids isolated from the strains of Y. enterocolitica 0:3 and Y. pseudotuberculosis I was 71.5 thousands and 62.7 thousands of base pairs respectively, and was in the range 60-75 thousands bp (40-50 Mda) reported in the literature for virulence plasmids of Yersinia. The study showed that finding of characteristic growth of Yersinia organisms on the CRMOX medium can be useful for the detection of strains containing the pYV virulence plasmid and for the determination of their potential pathogenicity.

[Occurrence of P.fimbrii in strains from selected genera of Enterobacteriaceae]

This study was aimed at recognition of frequency of occurrence of P fimbriae in strains of Escherichia coli isolated from samples of feces of children with symptoms of diarrhoea and at search of these adhesions in strains representing other than Escherichia genera of Enterobacteriaceae strains. One hundred forty laboratory strains were investigated. They belonged to genus Citrobacter, Enterobacter, Hafnia, Klebsiella, Morganella, Proteus, Providencia, Salmonella, Shigella, and Yersinia. Also were tested 1277 colonies of enteric rods isolated from the MacConkey's medium inoculated with samples of feces from 163 children with symptoms of diarrhoea. Mannose-resistant active hemagglutination test was performed with human group O erythrocytes and guinea pig erythrocytes stabilized with glutaraldehyde. Presence of P fimbriae was detected by the slide latex test with latex covered by P1 glycoprotein. Among 140 laboratory strains of Enterobacteriaceae in 21 strains (3-E. cloaceae, 2-Hafnia, 13-K. pneumoniae, 2-P. rettgeri and in one strains of Providencia) presence of MRHA adhesins was demonstrated. Nine of these strains (2-Hafnia, 5-K. pneumoniae and 2-P. rettgeri) reacted specifically in the latex test. Among 1142 colonies of E. coli isolated from children with symptoms of diarrhoea, 326 colonies belonged to 13 EPEC serotypes. With 118 (36.2%) of EPEC colonies a positive result of MRHA reaction was found with human erythrocytes and 34 (10.4%) with guinea pig erythrocytes. Positive latex test was obtained with 77 (23.6%) colonies. All these colonies possessed MRHA adhesins. Remaining 816 colonies of E. coli strains did not represent microorganisms belonging to serotypes accepted as enteropathogenic. From 112 (13.7%) colonies out of 816 not belonging to EPEC, positive results was obtained in the MRHA test with human erythrocytes and this was the case also with 41 (5.0%) colonies in MRHA reaction with application of guinea pig erythrocytes. The latex test was positive in 65 (7.9%) colonies of E. coli. From remaining 135 colonies other than E. coli, positive result of latex test of presence of P fimbriae was obtained with 54 (40.0%) colonies, including 14 colonies of E. cloacae, 23-K. pneumoniae and 17-K. oxytoca. In all these strains presence of MRHA adhesins was demonstrated. These investigations demonstrated that among EPEC strains significantly more frequently, than not belonging to these serotypes of E. coli, MRHA adhesins, including P fimbriae was observed.(ABSTRACT TRUNCATED AT 400 WORDS)