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G Lehnert

Publications and source records attributed to G Lehnert.

At least 19 recordsLinked to original sources
PubMed2002

Carcinogen-specific mutation pattern in the p53 tumour suppressor gene in UV radiation-induced basal cell carcinoma.

OBJECTIVES: Basal cell carcinoma (BCC) is mainly caused by high and long-term UV radiation. UV radiation causes DNA damage in various genes. Mutations of the p53 tumour suppressor gene have been identified in a wide variety of human cancers. The aim of the study was to analyse specific p53 mutations in BCCs in workers exposed to high and long-term UV radiation. METHODS: The mutation pattern of the p53 tumour suppressor gene was analysed in tissue from 12 patients with UV-related BCC. All patients had a suspected occupational disease notified within the period 1995-1999. As a control, 20 BCC skin samples removed from areas definitively unexposed to sunlight were analysed. The specific mutations were determined by direct sequencing of codon 4 to 9 of the p53 gene in carcinomatous and adjacent non-neoplastic tissue after microdissection. Immunohistochemical analysis was performed to detect p53 protein. RESULTS: p53 mutations were detected in 7/12 cases (58%). Point mutations were found in six cases (50%). In one case a deletion of 24 base pairs was observed. The most frequent mutations we found were CC-->TT base-pair changes in four and C-->T mutations in two cases. Within the control group specific p53 mutations were found in 11 cases (55%) without any C-->T predominance. No case showed CC-->TT mutations. CONCLUSIONS: Mutations of the p53 tumour suppressor gene in UV-associated BCC are frequent events. A predominance of C-->T mutations and tandem CC-->TT base-pair changes were observed in the sunlight-exposed cases only supporting the idea of site-directed mutagenesis by UV radiation in human BCC.

Base Sequence↗
PubMed2001

Frequent k- ras -2 mutations and p16(INK4A)methylation in hepatocellular carcinomas in workers exposed to vinyl chloride.

Vinyl chloride (VC) is a know animal and human carcinogen associated with liver angiosarcomas (LAS) and hepatocellular carcinomas (HCC). In VC-associated LAS mutations of the K- ras -2 gene have been reported; however, no data about the prevalence of such mutations in VC associated HCCs are available. Recent data indicate K- ras -2 mutations induce P16 methylation accompanied by inactivation of the p16 gene. The presence of K- ras -2 mutations was analysed in tissue from 18 patients with VC associated HCCs. As a control group, 20 patients with hepatocellular carcinoma due to hepatitis B (n = 7), hepatitis C (n = 5) and alcoholic liver cirrhosis (n = 8) was used. The specific mutations were determined by direct sequencing of codon 12 and 13 of the K- ras -2 gene in carcinomatous and adjacent non-neoplastic liver tissue after microdissection. The status of p16 was evaluated by methylation-specific PCR (MSP), microsatellite analysis, DNA sequencing and immunohistochemical staining. All patients had a documented chronic quantitated exposure to VC (average 8883 ppmy, average duration: 245 months). K- ras -2 mutations were found in 6 of 18 (33%) examined VC-associated HCCs and in 3 cases of adjacent non-neoplastic liver tissue. There were 3 G --> A point mutations in the tumour tissue. All 3 mutations found in non-neoplastic liver from VC-exposed patients were also G --> A point mutations (codon 12- and codon 13-aspartate mutations). Hypermethylation of the 5' CpG island of the p16 gene was found in 13 of 18 examined carcinomas (72%). Of 6 cancers with K- ras -2 mutations, 5 specimens also showed methylated p16. Within the control group, K- ras -2 mutation were found in 3 of 20 (15%) examined HCC. p16 methylation occurred in 11 out of 20 (55%) patients. K- ras -2 mutations and p16 methylation are frequent events in VC associated HCCs. We observed a K- ras -2 mutation pattern characteristic of chloroethylene oxide, a carcinogenic metabolite of VC. Our results strongly suggest that K- ras -2 mutations play an important role in the pathogenesis of VC-associated HCC.

Adult↗
PubMed2001

Internal exposure to polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs) of Bavarian chimney sweeps.

This study was carried out to evaluate the internal exposure to polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs) of chimney sweeps in Bavaria compared to a control group without occupational exposure. The PCDD/PCDF concentrations in the blood fat of 227 chimney sweeps were compared with the concentrations in samples from 60 controls. Using an internal standard containing 17 (13)C(12)-labeled PCDD/F congeners, the samples were cleaned up after fat elution using standard methods. The statistical analysis was adjusted to account for demographic differences, dietary habits, smoking status, and both occupational and nonoccupational contact with chlorinated hydrocarbons. Detailed information on the type of heating in the households swept, the length of time the chimney sweeps had carried out the profession (min 34, med 195, max 466 months) and the protective measures employed, were used to examine the influence of the working conditions specific to chimney sweeps on the internal PCDD/PCDF exposure. The correlation between blood-fat PCB concentrations as well as urinary chlorophenol concentrations and the exposure to PCDDs/PCDFs was evaluated. The sum of PCDD/PCDF components in chimney sweeps, expressed by International Toxic Equivalents (I-TEQ), was significantly increased compared to the control group (median: 26.36 versus 20.75 pg I-TEQ/g blood fat). For 37 chimney sweeps (16.3%) the sum of PCDDs/PCDFs exceeded the 95th percentile of the control group, i.e., 38.23 pg I-TEQ/g blood fat. Multiple regression analysis revealed that in addition to occupation, the variables age, district, and proximity to a waste incineration plant seem to have an effect on the internal PCDD/PCDF exposure. An additional influence on the internal exposure could not be determined for any of the special aspects of the work. We identified no high correlations between the concentrations of PCBs and chlorophenols and PCDDs/PCDFs. This study revealed significantly higher internal exposure to PCDDs/PCDFs in chimney sweeps than in the control group. The differences are small and within the range of the internal exposure to PCDDs/PCDFs in blood found in the general population in Germany since 1989. Further investigations in to PCDD/PCDF-related diseases in these study groups were not carried out.

Adult↗
PubMed2000

[Assessment of teaching at the faculties of medicine in Germany].

BACKGROUND AND OBJECTIVES: The aim of this study was to gather, against the background of a long-discussed deficit in academic teaching, data on the current activities of medical faculties with regard to teaching, and to analyse these findings. Another aim was to obtain suggestions for establishing a consensus on indicators that could be used to assess the quality of teaching. MATERIAL AND METHODS: In March 2000, a written inquiry was addressed to the deans of all 37 medical faculties in Germany. The questionnaire, arranged so that responses could be entered into a data-base, consisted of ten items in three parts. Part 1 concerned the evaluation of teaching, parts 2 and 3 dealt with the place of specific assessment of teaching in the process of choosing lecturers ("habilitation") and appointing senior professors. In addition to providing alternative answers (in some instances, allowing a choice of several alternatives) there was also space for written comments. The answers were analysed by descriptive statistics. RESULTS: All questionnaires were returned in a usable form (response rate 100%). 36 faculties had, at the time of receiving the questionnaire, already instituted teaching assessments, of clinical teaching sessions more often than preclinical ones (97% vs 89%). The most widespread method of assessment consisted of obtaining students' opinion and of using the centralized written examinations of the institute for Medical and Pharmaceutical Examination Questions. In more than half of the faculties (57%) an above-average teaching performance by teachers was acknowledged in special ways (honours/prizes). In 31 faculties (84%) teaching experience counted as an absolute prerequisite for obtaining a lectureship, but as a rule without employing any defined standards. With regard to the selection of senior professors, 27 faculties (73%) explicitly took teaching competence into account. Defined criteria for assessing teaching ability were largely absent. CONCLUSIONS: The assessment of teaching quality can be considered as well established at medical faculties in Germany. However, the methods and models used are highly heterogeneous. Furthermore, numerous activities exist in the various faculties to increase the importance attached to academic teaching. However, despite using diverse indicators of quality, the central problems for assessing teaching ability remain unsolved.

Faculty, Medical↗
PubMed2000

[The medical dissertation. An assessment from the viewpoint of successful and unsuccessful candidates].

BACKGROUND: The actual value of medical dissertations is under current discussion. Studies concerning medical dissertation focused on successful candidates only. Therefore, data about physicians without "MD" are still lacking. PERSONS AND METHODS: We therefore performed a representative study of both, physicians with and without the "Dr. med." degree. Using an anonymous questionnaire we asked for reasons to perform a doctoral thesis. RESULTS: A total of 321 questionnaires could be evaluated (successful candidates n = 181; unsuccessful candidates n = 140). Nearly 96% have attempted to perform a medical dissertation at the beginning of their studies. Only 4% never had this intention. However, 67% answered that writing a medical dissertation has no relevance in clinical practice. For 80% of the successful physicians, it was the first attempted dissertation, they judged the supervision as very good or good. Physicians who did not write a medical dissertation stated that deficits in planning and supervising were the main reason for prematurely breaking off. 90% of the successful dissertationists thought that it had been personally meaningful and recommended the procedure to younger physicians. However, two-thirds of the practicing physicians without "MD" still intend to write a thesis. CONCLUSION: We conclude that the medical dissertation is highly rated in terms of personal and scientific value and should therefore remain a part of medical studies and science.

Academic Dissertations as Topic↗
PubMed2000

[Medical habilitation. Accepted academic qualifications or outdated formalism?].

BACKGROUND: With the changes in the structure of education and society, in recent years also the medical habilitation (German postdoctoral lecturing qualification) has been called into question as an academic qualification. With this in mind, the aim of our study was to discover the current opinion of those who had successfully completed a habilitation on the prerequisites for a habilitation, the habilitation procedure and the status of a habilitation, and to document potential wishes for reform. COLLECTIVE AND METHODS: The target group of our survey were the 616 persons (female: 77, male 539) who successfully completed their habilitation in 1997 at one of the 36 German medical faculties. The database was formed by an anonymous questionnaire (23 items), which included questions on sociodemographic factors and occupational history (general part), and subjective opinions (specific part). Recruitment of the participants in the survey and passing on of the questionnaire were carried out by the office of the medical dean of the various universities, as the names of those who had completed a habilitation were not available to the investigators for reasons of protecting the individual's rights and identity. Evaluation of the returned questionnaires was carried out using descriptive statistics. Subgroups were formed according to sex, age and subject groups. RESULTS: The questionnaire was answered in a useable form by 389 persons (female: 46, male 343) from 35 medical faculties (return quota 63%). 95% of those who took part in the survey were registered doctors; 79% of these came from clinics, 16% from the field of theoretical medicine. 81% were specialist physicians. 5% had studied the natural sciences or humanities. The median age at the time of completing the habilitation was 38 years (minimum 30, maximum 54 years old). At present 93% were assistant professors, 5% were professors. The median interval between the doctoral thesis and habilitation was 10 years. 58% had carried out a period of research abroad. In 90% of cases the persons had written a postdoctoral thesis for their habilitation, 10% qualified cumulatively. 47% had improved their occupational rank within a period of 2 years after completing the habilitation, about 2/3 of these reached senior positions. Among the prerequisites for habilitation, "Humboldt's trias" (research, teaching and caring for patients) was accepted by the great majority. Other prerequisites regarded as important for habilitation were publications, holding talks, specialist status and experience abroad. Impact factors, however, should be regarded as important conditions for habilitation only in combination with other criteria. The value of a habilitation was not called into question; 89% would recommend completing one. 80% of those questioned, however, thought the procedure for completing a habilitation should be optimized. The general abolition of the medical habilitation was, however, not desired by the vast majority. CONCLUSION: The value of completing a medical habilitation is not a point for debate for most of those who successfully completed one. It remains the springboard for occupational advancement. The vast majority do not wish to see it abolished. Also the usual prerequisites for habilitation are accepted by the majority of persons. The procedure for completing a habilitation is, however, regarded as in need of improvement. There is a wide consensus of opinion regarding potential aims for reform.

Adult↗
PubMed2000

p53 mutation pattern in hepatocellular carcinoma in workers exposed to vinyl chloride.

BACKGROUND: Vinyl chloride (VC) is a known animal and human carcinogen that is associated with liver angiosarcoma and most likely also with hepatocellular carcinoma (HCC) in humans. METHODS: The authors examined the presence of p53 gene mutations in 18 HCC specimens from patients with known exposure to VC (median, 8883 parts per million-years; median duration, 245 months). In all cases, other risk factors for the development of HCC (hepatitis B virus and hepatitis C virus infections, alcohol consumption, and metabolic or autoimmune disorders) were excluded. Three patients had concomitant cirrhosis. The p53 gene was examined by direct sequencing of exons 5-9. RESULTS: Mutations of the p53 gene were found in 11 of 18 HCCs examined. The point mutations detected were comprised of five transversions and five transitions. Five of 11 mutations (codons 175, 245, 248, 273, and 282) occurred at CpG sites. Histopathologic liver alterations (mild sinusoidal dilatation, [portal] fibrosis, and centrilobular siderosis) in tumor surrounding nonneoplastic liver confirmed exposure to VC. CONCLUSIONS: The results of the current study indicated a relation between VC exposure and the development of HCC. The mutation pattern of p53 with a nearly equal rate of incidence of transitions and transversions and a high rate of incidence of mutations at CpG sites may reflect endogenous mechanisms (e.g., deamination of 5-methylcytosine) rather than exogenous carcinogens.

Aged↗
PubMed2000

Longitudinal study of neurotoxicity with occupational exposure to aluminum dust.

Two cross-sectional studies were conducted at a German aluminum (Al) powder plant to evaluate possible nervous system effects from occupational Al exposure. The investigation included biological monitoring, a neuropsychological test battery, and event-related P300 potentials. Neurophysiologic findings in workers chronically exposed to Al dust did not differ from non-Al-exposed controls from the same plant. The authors suggest that chronic exposure to Al dust, at the levels documented in this study, does not induce measurable cognitive decline.

Adult↗
PubMed1999

Are snoring medical students at risk of failing their exams?

STUDY OBJECTIVES: To compare the examination results of self-reported snoring and nonsnoring medical students DESIGN: We studied the examination scores obtained by medical students answering a multiple-choice test forming part of their final examinations. The students were asked to classify themselves as "nonsnorers," "occasional snorers," or "frequent snorers," and to state their age, sex, height and weight. SETTING: University Hospital, Erlangen, Germany PARTICIPANTS: 201 medical students (61% males/39% females; mean age 24.6 +/- 2.1 years; BMI 22.4 +/- 2.5 kg/m2) taking their final examinations in internal medicine. MEASUREMENTS AND RESULTS: Seventy-eight students (38.8%) claimed to be nonsnorers, 99 (49.3%) occasional snorers and 24 (11.9%) frequent snorers. The mean examination scores (adjusted for age, sex, and BMI) were 69.6 +/- 9.9% for the nonsnorers, 65.3 +/- 10.0% for the occasional snorers and 62.0 +/- 8.2% for the frequent snorers (p < 0.0001). 12.8% of the nonsnorers failed the exam, compared with 22.2% of the occasional snorers and 41.7% of the frequent snorers (p < 0.001). Logistic regression analysis showed an association between failing the exam and snoring (p = 0.013), but not between failure and age, BMI, or sex (relative risk for snorers adjusted for age, sex and BMI: 1.26; 95%--CI 1.01-1.57). CONCLUSIONS: In medical students, snoring seems to be associated with an increased risk of failing exams in a dose-response manner, even after controlling for age, sex and BMI. For the present, the mechanisms underlying this association must remain a matter of speculation. Snoring-related sleep fragmentation ("upper airway resistance syndrome") might be a causal factor.

Achievement↗
PubMed1999

[Hearing loss caused by leisure noise].

Although noise in general can induce hearing loss, environmental noise represents an important risk for children, teenagers and young adults. Epidemiological investigations now support the occurrence of an increasing number of irreversible hearing losses in these groups. Major causes of hearing loss are toys (guns), explosives and electroacoustically amplified music delivered by head sets or heard in discotheques and open air concerts. Clinical indications are discussed.

Adolescent↗
PubMed1999

Osp17, a novel immunodominant outer surface protein of Borrelia afzelii: recombinant expression in Escherichia coli and its use as a diagnostic antigen for serodiagnosis of Lyme borreliosis.

Western blot analyses of the human humoral response of patients with Lyme borreliosis have shown that a 17-kDa protein is an immunodominant protein in late disease. Immune electron microscopy with a monoclonal antibody against this protein revealed that the 17-kDa protein is abundantly expressed on the surface of Borrelia afzelii strain PKo. Therefore, the protein has been renamed outer surface protein (Osp) 17. Recombinant Osp 17 of strain PKo was expressed in Escherichia coli and purified by chromatography. Immunoblot analysis of human sera showed a comparable sensitivity with recombinant and natural proteins. The DNA sequences of the osp17 genes from different B. afzelii strains were determined. The DNA sequences of the different osp 17 homologues (six isolates from skin, three isolates from CSF and one isolate from synovial fluid) had high sequence identities of at least 94%. Using a polyclonal antibody against recombinant Osp 17, it was shown that Osp 17 expression varied considerably among the investigated B. afzelii strains. As previously also observed for OspA- and OspC-encoding genes, the osp 17 gene is present in strains not expressing the respective protein. It has been shown that OspA and OspC expression varies in different environments such as tick and vertebrate host. Studies are underway to examine whether this is also true for Osp 17. For diagnostic purposes the use of recombinant Osp 17 has the advantage that the amount of Osp 17 antigen can be easily standardized for immunoblotting, and that this antigen can be used in a protein-specific enzyme-linked immunosorbent assay.

Animals↗
PubMed1999

An improved recombinant IgG immunoblot for serodiagnosis of Lyme borreliosis.

We have previously described the use of the following recombinant antigens for serodiagnostic immunoblots: p83/100, p39, OspC and p41 (flagellin) internal fragment [Wilske et al. (1993) Med Microbiol Immunol 182:255-270; Rossler et al. (1997) J Clin Microbiol 35:2752-2758]. In our currently used immunoblot p83/100 is derived from strain PKo (Borrelia afzelii), p39 (BmpA) and OspC from strains PKa2 (B. hurgdorferi sensu stricto), PKo and PBi (B. garinii), respectively; the p41 (flagellin) internal fragments were cloned from strains PKo and PBi. In this study we describe the use of two additional recombinantly expressed highly immunogenic proteins Osp 7 (derived from PKo) and p58 (derived from PBi). A clinically well-defined panel of sera from 147 Lyme borreliosis patients and 139 controls previously tested by a standardized whole cell lysate immunoblot [Hauser et al. (1997) J Clin Microbiol 35:1433-1444] was investigated in the recombinant immunoblot without (old recombinant immunoblot) and with Ospl7 and p58 (new recombinant immunoblot) for IgG antibodies. The sensitivity of the recombinant IgG immunoblot for diagnosis of stage II and stage III could be significantly improved by addition of Osp17 and p58 without loss of specificity. With the exception of sera from patients with erythema migrans the diagnostic sensitivity is comparable to the whole cell lysate IgG immunoblot. The main advantage of the recombinant immunoblot is the easy identification of diagnostic bands, whereas the identification of bands in the whole cell lysate immunoblot is difficult. The recombinant immunoblot is especially suitable where large series of sera need to be investigated.

Animals↗
PubMed1999

A heated humidifier reduces upper airway dryness during continuous positive airway pressure therapy.

Upper airway dryness is a frequent side-effect of nasal continuous positive airway pressure (nCPAP) therapy in obstructive sleep apnoea (OSA). In this situation, heated humidification is often used. Alternatively, oily nose drops are frequently applied to relieve dryness. The present study aimed to investigate the efficacy of a heated humidifier in comparison with oily nose drops. Twenty-four OSA patients complaining of serious nCPAP-related upper airway dryness were randomized to 6 weeks of treatment either with heated humidification (HC 100, Fischer & Paykel, Inc., Auckland, New Zealand) or oily nose drops (Colda-Stop, Desitin, Inc., Germany). The patients completed questionnaires on the degree and frequency of upper airway dryness, compliance with nCPAP, intention to terminate nCPAP and comfort during the nCPAP therapy. All 12 patients treated with heated humidification improved in terms of the degree and frequency of upper airway dryness, and reported greater comfort when using the nCPAP device. All patients in the heated humidification group intending to terminate nCPAP therapy because of upper airway dryness persisted with nCPAP on addition of humidification. In contrast, only five out of 12 patients (42%) in the oily nose drops group reported their degree of upper airway dryness to be improved (P = 0.003), only three patients (25%) reported an improvement in the frequency of upper airway dryness (P < 0.001), and only five patients (42%) reported greater comfort when using the nCPAP device with oily nose drops (P < 0.001). In the group using oily nose drops none of the three patients who intended to terminate nCPAP therapy persisted with nCPAP. Heated humidification is highly effective and superior to oily nose drops in reducing the symptoms of upper airway dryness during nCPAP.

Aged↗
PubMed1999

Validity of interpretation criteria for standardized Western blots (immunoblots) for serodiagnosis of Lyme borreliosis based on sera collected throughout Europe.

Western blotting (WB; immunoblotting) is a widely used tool for the serodiagnosis of Lyme borreliosis (LB), but so far, no generally accepted criteria for performance and interpretation have been established in Europe. The current study was preceeded by a detailed analysis of WB with whole-cell lysates of three species of Borrelia burgdorferi sensu lato (U. Hauser, G. Lehnert, R. Lobentanzer, and B. Wilske, J. Clin. Microbiol. 35:1433-1444, 1997). In that study, interpretation criteria for a positive WB result were developed with the data for 330 serum samples (from patients with LB in different stages [n = 189] and from a control group [n = 141]) originating mostly from southern Germany. In the present work, the interpretation criteria for strains PKo (Borrelia afzelii) and PBi (Borrelia garinii) developed in the previous study were reevaluated with 224 serum samples (from patients with LB in different stages [n = 97] and from a control group [n = 127]) originating from throughout Europe that were provided by the European Union Concerted Action on Lyme Borreliosis (EUCALB). De novo criteria were developed on the basis of the reactivities of the EUCALB sera and were evaluated with the data for the samples from southern Germany. Comparison of all results led to the following recommendations: For WB for immunoglobulin G (IgG), at least two bands among p83/100, p58, p43, p39, p30, OspC, p21, p17, and p14 for PKo and at least one band among p83/100, p39, p30, OspC, p21, and p17b for PBi; for WB for IgM, at least one band among p39, OspC, and p17 or a strong p41 band for PKo and at least one band among p39 and OspC or a strong p41 band for PBi. WB with PKo was the most sensitive, and this strain is recommended for use in WB for the serodiagnosis of LB throughout Europe.

Blood Donors↗
PubMed1999

["Doctor" without being an M.D.--how do non-graduate MDs view medical dissertations?].

Both the ranking and the quality of medical dissertations have for some time been a controversial moot point. Previous studies showed that successful doctorate candidates still regard medical dissertations as a meaningful addition to medical studies. Studies on the views of the value have been placed on a medical dissertation by practising physicians who did not write a dissertation lacking to date. Using an anonymous questionnaire containing 16 questions we carried out a study of all the practising doctors in Mid-Franconia, Germany, who did not write a dissertation (n = 243). We asked about their intentions to write a dissertation, reasons for prematurely breaking off the dissertation and their views on the value of medical dissertations. Evaluation was carried out using descriptive statistics in the sense of an exploratory data analysis. The questionnaire was answered in a usable form by 140 physicians (return quote 58%). The average age of the participants was 44 years (33-89 years). The vast majority (89%) had attempted one or several dissertations, 32% still intended to write a dissertation. 59% regarded writing a dissertation alongside daily practice as very difficult of impossible. Private/family reasons were stated less often than deficits in planning, implementation and supervision for prematurely breaking off the dissertation. 65% of the practising physicians in Mid-Franconia who did not write a dissertation regard medical dissertation today as no longer relevant. 58% are of the opinion that the title "doctor" should be awarded automatically with the final exams. The majority of practising physicians asked had in the meantime given up their intention of writing a dissertation and today tend to disfavour medical dissertations. Nevertheless, one third of those who participated in the study still intend to write a dissertation. In view of this it should be discussed to what extent practising physicians interested in scientific questions can be helped to write a dissertation alongside their daily practice. In particular professors and lecturers of general medicine are called upon to make this possible.

Academic Dissertations as Topic↗
PubMed1998

Genospecies and their influence on immunoblot results.

In Europe at least three human pathogenic species of Borrelia burgdorferi sensu lato are the causative agents of Lyme borreliosis. All three species have been isolated or detected by PCR from skin, CSF and synovial fluid of patients with skin lesions, neuroborreliosis and Lyme arthritis respectively. Studies using strains representing the three species as antigen for the immunoblot revealed that interpretation criteria depend strictly on the strain used as antigen. More than using certain species as antigen it is important to use strains (f.e. B. afzelii strain PKo) expressing certain immunodominant antigens like OspC and p17 which may not be expressed by other strains in vitro. Using strain PKo as antigen the two band criterium can be used without loss of too much sensitivity compared to using B. burgdorferi sensu stricto strain PKa2 and B. garinii strain PBi. The use of recombinant antigens allows selection of highly specific and combination of homologous antigens from different strains; however not all desirable antigens have been recombinantly expressed. Addition of p17 and p58 as antigens may improve the sensitivity of the hitherto described recombinant antigen immunoblots containing the antigens p83/100, p39, OspC and the p41 internal fragment.

Animals↗
PubMed1998

[Secondary obstructive sleep apnea syndrome in a patient with tracheal stenosis and bilateral recurrent paresis. Successful treatment with nasal continuous positive airway pressure therapy].

HISTORY AND ADMISSION FINDINGS: A 67-year-old woman complained of marked daytime sleepiness, as well as loud snoring and apnoeas during sleep. She was known to have had 3 thyroidectomies for goitre 41, 23 and 12 years ago, with known tracheal stenosis and recurrent nerve palsy for 11 years. Physical examination revealed marked stridor, hoarse voice and slightly enlarged and palpable recurrent right thyroid. INVESTIGATIONS: Polysomnography demonstrated a clearly elevated obstructive sleep apnoea activity (apnoea index: 34/h, apnoea-hypopnea index: 40/h, desaturation index: 31/h, minimal saturation: 63%). Selective tracheal imaging showed subglottic tracheal stenosis with an inspiratory luminal diameter of 4 mm and an expiratory luminal diameter of 8 mm. Lung function analysis revealed marked flattening of the flow-volume curve as sign of a functionally effective tracheal stenosis. These findings indicated a secondary obstructive sleep apnoea (OSA) due to tracheal stenosis and bilateral recurrent nerve palsy. The patient declined further studies, such as bronchoscopy. TREATMENT AND COURSE: As the patient did not want any surgical treatment, nasal continuous positive airway pressure therapy (CPAP) was instituted as a trial. No apnoea occurred at a pressure of 12 mm H2O and this was well tolerated. She has now continued CPAP at home for 12 months and her vigilance was markedly improved. CONCLUSIONS: Tracheal stenosis or recurrent nerve palsy is a rare cause of OSA which can be effectively treated by nasal CPAP.

Aged↗