Biomedical subjects

Richard Maier

Publications and source records attributed to Richard Maier.

5 recordsLinked to original sources

PubMed2006

Application of multiplex cytometric bead array technology for the measurement of angiogenic factors in the vitreous.

PURPOSE: This study was carried out to compare cytometric bead array (CBA) technology with conventional enzyme linked immunosorbent assay (ELISA) for the measurement of both vitreous and serum concentrations of interleukin-8 (IL-8), vascular endothelial growth factor (VEGF), and angiogenin (ANG) in diabetic and non-diabetic patients. METHODS: Measurement of vitreous and serum concentrations of IL-8, VEGF, and ANG using both ELISA and CBA was performed in 26 probands (13 diabetics and 13 non-diabetic control subjects). RESULTS: Vitreous and serum concentrations of IL-8, VEGF, and ANG determined by CBA showed a strong correlation with those measured by ELISA. Vitreous levels of IL-8, VEGF, and ANG were significantly higher in diabetics compared to non-diabetic control subjects. No significant correlation between vitreous and serum levels of any of the investigated parameters were found in either diabetics or control individuals. CONCLUSIONS: The present study is the first to utilize cytometric bead array technology for the measurement of angiogenic factors in the vitreous. Measurements obtained by ELISA and CBA technologies were highly correlated for IL-8, VEGF, and ANG in both vitreous and serum samples. Diabetic individuals showed significant elevation of IL-8, VEGF, and ANG in the vitreous but not in serum samples compared to control subjects. The most striking advantage of the CBA technology is the fact that numerous parameters can be measured in parallel using a comparatively small sample volume. It is therefore more rapid and cost effective than ELISA technology. CBA technology is a new, accurate method to measure IL-8, VEGF, and ANG in the vitreous.

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PubMed2005

Effects of short- and long-term unemployment on physical work capacity and on serum cortisol.

AIM: To investigate whether a decrease in physical working capacity occurs during the first year of unemployment and if this is accompanied by a deterioration in mental health. METHODS: In a longitudinal study, 71 unemployed individuals were investigated for 1, 6 months and 1 year after becoming unemployed. An additional 102 individuals who have been unemployed for more than 1 year were included in the cross-sectional part of the study. Possible decrease of physical working capacity was tested by bicycle ergometry. Psycho-emotional stress was tested by serum cortisol concentrations and by the Giessen symptom questionnaire. RESULTS: In short-term unemployed (STU) individuals, a significant decrease (P=0.001) of physical working capacity (16.3%) and a significant increase (P=0.004) of cortisol levels (17.6 microg/dl) was found. The Giessen symptom questionnaire score showed an increased emotional disturbance (P=0.035) during unemployment. The comparison of long-term unemployed and STU revealed a significant decrease (P=0.012) in physical working capacity (18.2%), a significant increase in cortisol levels (P=0.001) and a significant worsening of the Giessen symptom questionnaire score (P=0.001). CONCLUSION: Unemployment has a negative effect on physical working capacity and mental health, depending on the duration of unemployment. Factors that facilitate or impede physical and mental health during unemployment should be identified in future studies.

Adult↗

PubMed2005

Welder's maculopathy?

OBJECTIVE: The aim of this study was to verify or to disprove whether the term 'Welder's maculopathy' or 'Welding arc maculopathy' has to be considered being a justifiable occupational hazard and is to be annexed to the list of occupational diseases. METHODS: Multifocal electroretinography (MERG) and thorough ophthalmologic examinations were performed in a group of 89 welders. The matched control group comprised 81 subjects who had never been exposed to welding. All participants of this study were examined by a specialist of occupational medicine prior to the MERG. RESULTS: Multifocal electroretinography as well as ophthalmological tests did not reveal a significant morphological or functional differences between the welders and the control group. On an average, the welders' visual acuity appeared to be better than that of the control group. This phenomenon could be attributed to the so-called healthy worker effect. CONCLUSION: Welding arc maculopathy seems to be rather a sequel of occupational accidents and negligence of safety regulations. The results of this study indicate that the usual protective measures in professional welding appears to be sufficient in order to prevent an occupational risk of welding arc maculopathy.

Adult↗

PubMed2005

Endurance exercise training in orthostatic intolerance: a randomized, controlled trial.

Orthostatic intolerance is a syndrome characterized by chronic orthostatic symptoms of light-headedness, fatigue, nausea, orthostatic tachycardia, and aggravated norepinephrine levels while standing. The aim of this study was to assess the protective effect of exercise endurance training on orthostatic symptoms and to examine its usefulness in the treatment of orthostatic intolerance. 2768 military recruits were screened for orthostatic intolerance by questionnaire. Tilt-table testing identified 36 cases of orthostatic intolerance out of the 2768 soldiers. Subsequently, 31 of these subjects with orthostatic intolerance entered a randomized, controlled trial. The patients were allocated randomly to either a "training" (3 months jogging) or a "control" group. The influence of exercise training on orthostatic intolerance was assessed by determination of questionnaire scores and tilt-table testing before and after intervention. After training, only 6 individuals of 16 still had orthostatic intolerance compared with 10 of 11 in the control group. The Fisher exact test showed a highly significant difference in diagnosis between the 2 groups (P=0.008) at the end of the study. Analysis of the questionnaire-score showed significant interaction between time and group (P=0.001). The trained subjects showed an improvement in the average symptom score from 1.79+/-0.4 to 1.04+/-0.4, whereas the control subjects showed no significant change in average symptom score (2.09+/-0.6 and 2.14+/-0.5, respectively). Our data demonstrate that endurance exercise training leads to an improvement of symptoms in the majority of patients with orthostatic intolerance. Therefore, we suggest that endurance training should be considered in the treatment of orthostatic intolerance patients.

Adult↗

PubMed2002

Chlamydia pneumoniae seropositivity and the risk of nonarteritic ischemic optic neuropathy.

OBJECTIVE: To determine whether IgG antibodies to Chlamydia pneumoniae are associated with nonarteritic ischemic optic neuropathy (NAION). DESIGN: Retrospective case-control study. PARTICIPANTS: The study cohort consisted of 71 consecutive patients with NAION and 71 controls matched for age and gender. MAIN OUTCOME MEASURES: Serum immunoglobulin G (IgG) antibody titers to Chlamydia pneumoniae. RESULTS: Patients with NAION had significantly higher IgG antibody titers to C. pneumoniae compared with control subjects (IgG titer > or =1:128: 29 patients versus 15 controls, P = 0.017). The odds ratio for patients with an IgG titer > or =1:128 was 2.56 (95% confidence interval [CI], 1.2-5.5). Adjustment for arterial hypertension, diabetes mellitus, and myocardial infarction resulted in an odds ratio of 3.48 (95% CI, 1.3-9.6). CONCLUSIONS: Our results suggest that elevated titers of IgG antibodies to C. pneumoniae are associated with NAION.

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