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1.
iScience ; 26(10): 107981, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37860771

ABSTRACT

Columnar mesoporous silicon (PSi) with hydrophobic vs. hydrophilic chemistries was chosen as a model for the local (pore-by-pore) study of water-pore interactions. Tomographic reconstructions provided a 3D view of the ramified pore structure. An in situ study of PSi wetting was conducted for categorized pore diameters by environmental scanning TEM. An appropriate setting of the contrast allows for the normalization of the gray scale in the images as a function of relative humidity (RH). This allows constructing an isotherm for each single pore and a subsequent averaging provides an isotherm for each pore size range. The isotherms systematically point to an initial adsorption through the formation of water adlayers, followed by a capillary filling process at higher RH. The local isotherms correlate with (global) gravimetric determination of wetting. Our results point at the validation of a technique for the study of aging and stability of single-pore nanoscale devices.

2.
Arch Gynecol Obstet ; 305(6): 1517-1524, 2022 06.
Article in English | MEDLINE | ID: mdl-35597817

ABSTRACT

BACKGROUND: To achieve long-term improvement in health care of transgender women, it is necessary to analyze all aspects of gender-confirming surgery, especially the relation of risks and benefits occurring in these procedures. While there are many studies presenting data on the urologic part of the surgery, there are just few data about complications and satisfaction with breast augmentation. METHODS: This is a retrospective study using parts of the BREAST-Q Augmentation Questionnaire and additional questions for symptoms of capsular contracture and re-operations and analyzing archived patient records of all transwomen which were operated at University Hospital Essen from 2007 to 2020. RESULTS: 99 of these 159 patients (62%) completed the questionnaire after a median time of 4 years after surgery. Breast augmentation led to re-operations due to complications in 5%. The rate of capsular contracture (Baker Grad III-IV) in this population was 3%. Most patients (75%) rated high scores of satisfaction with outcome (more than 70 points) and denied to have restrictions due to their implants in their everyday life. All patients reported an improvement in their quality of life owing to breast augmentation. CONCLUSION: Breast augmentation by inserting silicon implants is a safe surgical procedure which takes an important part in reducing gender dysphoria.


Subject(s)
Breast Implantation , Breast Implants , Contracture , Mammaplasty , Breast Implantation/adverse effects , Breast Implantation/methods , Breast Implants/adverse effects , Contracture/epidemiology , Contracture/etiology , Contracture/surgery , Female , Follow-Up Studies , Humans , Mammaplasty/methods , Patient Satisfaction , Personal Satisfaction , Quality of Life , Retrospective Studies
3.
Sens Actuators A Phys ; 222: 301-308, 2015 Feb 01.
Article in English | MEDLINE | ID: mdl-26109748

ABSTRACT

Piezoelectric scandium aluminium nitride (Sc x Al1-x N) thin films offer a large potential for the application in micro electromechanical systems, as advantageous properties of pure AlN thin films are maintained, but combined with an increased piezoelectric actuation and sensing potential. Sc x Al1-x N thin films with x = 27% have been prepared by DC reactive magnetron sputtering to find optimized deposition parameters to maximize the piezoelectric constants d33 and d31. For the accurate and simultaneous measurement of these constants Laser Doppler Vibrometry has been applied and compared to finite element (FEM) simulations. The electrode design has been optimized to rotational symmetric structures enabling a 180° phase shifted excitation, so that a straight-forward comparison of experimental displacement curves with those obtained from FEM is feasible.

4.
Atheroscler Suppl ; 18: 233-40, 2015 May.
Article in English | MEDLINE | ID: mdl-25936331

ABSTRACT

BACKGROUND: Despite the fact that extracorporeal methods such as lipoprotein apheresis (LA) and hemodialysis (HD) are highly effective in improving the physical status of patients, these treatment options may possibly harm the psychological status and the health related quality of life (HRQL). METHODS: The occurrences of anxiety, depression and the HRQL of 111 study participants treated with LA (n = 41), HD (n = 41) or undergoing plateletpheresis (PD) (n = 29) were compared to the normal population (NP), using standardized questionnaires (anxiety and depression: Hospital Anxiety and Depression Scale (HADS), heart-focused anxiety: Cardiac Anxiety Questionnaire (CAQ) and HRQL: Short-Form Health Survey (SF-12)). Additionally, the subjective mental and physical stress of study participants was evaluated. RESULTS: LA females had a significantly elevated HADS-A score compared to PD and NP. Additionally, there was a trend toward higher HADS-A scores in the LA group compared to the HD group in females. In HD males HADS-A and -D scores increased compared to PD and NP. The CAQ revealed a significant increase in the CAQ-Fear scale in LA compared to HD and PD participants. The CAQ-Avoidance score showed significantly increased scores in LA and HD patients compared to PD and NP. In the CAQ-Attention scale the LA patients also showed significantly increased scores compared to PD and NP. The increased psychological symptoms were associated with significantly lower levels of objective and subjective HRQL in LA and HD patients compared to PD and NP. CONCLUSIONS: LA and HD patients had similarly increased presence of psychological symptoms with concurrent decreased quality of life compared to PD and the normal population, which may affect the outcome of the LA patients. Therefore, early psychosomatic screening and probable psychosomatic treatment should be performed.


Subject(s)
Blood Component Removal/psychology , Blood Donors/psychology , Blood Platelets , Hyperlipoproteinemias/therapy , Lipoproteins/blood , Mental Health , Quality of Life , Renal Dialysis/psychology , Adult , Aged , Anxiety/diagnosis , Anxiety/psychology , Biomarkers/blood , Blood Component Removal/adverse effects , Case-Control Studies , Cross-Sectional Studies , Depression/diagnosis , Depression/psychology , Female , Humans , Hyperlipoproteinemias/blood , Hyperlipoproteinemias/diagnosis , Hyperlipoproteinemias/psychology , Male , Middle Aged , Registries , Renal Dialysis/adverse effects , Risk Factors , Sex Factors , Surveys and Questionnaires , Treatment Outcome , Young Adult
5.
Int J Cardiol ; 169(5): 366-70, 2013 Nov 20.
Article in English | MEDLINE | ID: mdl-24182908

ABSTRACT

INTRODUCTION: Catheter ablation for idiopathic ventricular arrhythmia is well established but epicardial origin, proximity to coronary arteries, and limited accessibility may complicate ablation from the venous system in particular from the great cardiac vein (GCV). METHODS: Between April 2009 and October 2010 14 patients (56 ± 15 years; 9 male) out of a total group of 117 patients with idiopathic outflow tract tachycardias were included undergoing ablation for idiopathic VT or premature ventricular contractions (PVC) originating from GCV. All patients in whom the PVC arose from the GCV were subject to the study. In these patients angiography of the left coronary system was performed with the ablation catheter at the site of earliest activation. RESULTS: Successful ablation was performed in 6/14 (43%) and long-term success was achieved in 5/14 (36%) patients. In 4/14 patients (28.6%) ablation was not performed. In another 4 patients (26.7%), ablation did not abolish the PVC/VT. In the majority, the anatomical proximity to the left coronary system prohibited effective RF application. In 3 patients RF application resulted in a coronary spasm with complete regression as revealed in repeat coronary angiography. CONCLUSION: A relevant proportion idiopathic VT/PVC can safely be ablated from the GCV without significant permanent coronary artery stenosis after RF application. Our data furthermore demonstrate that damage to the coronary artery system is likely to be transient.


Subject(s)
Catheter Ablation/methods , Coronary Vessels , Tachycardia, Ventricular/diagnostic imaging , Tachycardia, Ventricular/surgery , Ventricular Premature Complexes/diagnostic imaging , Ventricular Premature Complexes/surgery , Adult , Aged , Catheter Ablation/adverse effects , Coronary Vessels/diagnostic imaging , Coronary Vessels/surgery , Female , Follow-Up Studies , Humans , Male , Middle Aged , Radiography , Risk Factors , Treatment Outcome
6.
Trends Biotechnol ; 31(9): 530-8, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23849673

ABSTRACT

Tobacco mosaic virus (TMV) is the best-characterized virus. Compared to most other viruses, its structure and physical and chemical properties are well known. TMV exclusively infects plants and is completely harmless for mammals. This virus is resilient against environmental changes, and it can easily be modified with functional materials. Our review gives a summary about the known physical properties of TMV (structure, thermodynamics, and electromagnetism). We believe that the current progress in nanobiotechnology makes the fabrication of functional TMV-based biotechnology devices simpler than ever.


Subject(s)
Biotechnology/trends , Genetic Engineering/trends , Tobacco Mosaic Virus/chemistry , Tobacco Mosaic Virus/physiology , Amino Acid Sequence , Animals , Humans , Molecular Sequence Data , Nanotechnology/trends
7.
Eye (Lond) ; 26(1): 101-8, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21997359

ABSTRACT

PURPOSE: We measured the relationship between the occurrence of photopsias (spontaneous phosphenes), and retinitis pigmentosa (RP) subjects' level of vision, light exposure, and psychosocial factors to attempt to confirm RP patients' previous reports of these associations. METHODS: A total of 36 RP subjects self-administered PC-based binocular visual acuity, contrast sensitivity, and visual field tests at home twice a week, for 16 sessions in 2-3 months. After each session, subjects reported photopsias during the vision tests and completed questionnaires: Epworth Sleepiness Scale, Stanford Sleepiness Scale, Perceived Stress Scale, and Positive and Negative Affect Schedules. RESULTS: Across all subjects, photopsias occurred during 47% of sessions. Five (14%) subjects never noted photopsias, while five others noted photopsias at every session. Two-thirds of subjects experienced photopsias frequently (>20% of sessions). On average, the odds of noticing photopsias increased by 57% for every 1-point increase in mean perceived stress (OR = 1.57; 95% CI: 1.04, 2.4; P = 0.03) or reduced by 38% for every 1-point increase in positive mood (OR=0.62; 95% CI: 0.39, 0.98; P = 0.04), after adjusting for age, gender, and vision. Similarly, the odds of experiencing photopsias during a session increased by 16% for every 3-point increase in perceived stress and decreased by 17% for every 3-point increase in positive mood, after adjusting for age and gender (OR = 1.16; 95% CI: 1.01, 1.33; P = 0.048)(OR = 0.83; 95% CI: 0.73, 0.94; P = 0.004), respectively. Frequency of photopsias was not statistically significantly related to other factors measured. CONCLUSIONS: Increased photopsias appear to be related to times when subjects report increased perceived stress and/or decreased positive mood, rather than RP patients' age, level of vision, reported light exposure, or sleepiness.


Subject(s)
Hallucinations/psychology , Happiness , Retinitis Pigmentosa/psychology , Stress, Psychological/psychology , Adult , Contrast Sensitivity , Female , Hallucinations/etiology , Hallucinations/physiopathology , Humans , Male , Middle Aged , Phosphenes , Retinitis Pigmentosa/physiopathology , Surveys and Questionnaires , Visual Acuity
8.
Diabet Med ; 28(2): 168-74, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21219424

ABSTRACT

AIMS: To characterize bio-psycho-social factors, particularly mental disorders and self-harm behaviour, associated with the development of diabetic foot ulcers. METHODS: Two groups of diabetic patients with and without foot ulcers (n=47 in each group) with similar sex, age and diabetes duration were assessed for mental disorders using the Composite International Diagnostic Interview. Self-harm behaviour, quality of life, depressive symptoms and self-compassion were rated using different standard questionnaires. RESULTS: Patients from the ulcer group visited their practitioners and/or psychotherapists less frequently in the last 12 months than patients in the control group 0 vs. 13%; P=0.026). The ulcer group patients had a history of increased alcohol consumption (43 vs. 19%; P=0.025), lower levels of education (8 vs. 10 grades; P=0.014) and income (1190 vs. 1535 €/month; P=0.039). Additionally, they were less likely to be diagnosed with anxiety disorders (11 vs. 32%; P=0.022). No significant differences in glycated haemoglobin, body mass index, smoking and direct self-harm behaviour were identified. CONCLUSIONS: Patients with foot ulcers tend to exhibit lower health-conscious behaviour, particularly higher lifetime alcohol consumption, lower utilization of medical services and less general anxiety. Practitioners should be aware of these behaviours, since early detection of diabetes patients at psycho-social risk and consecutive psychological intervention may be an effective preventive strategy in avoiding the development of foot ulcers.


Subject(s)
Alcohol Drinking/adverse effects , Diabetes Mellitus, Type 2/complications , Diabetic Foot/etiology , Diabetic Neuropathies/psychology , Health Behavior , Patient Compliance/psychology , Self Care/psychology , Adult , Aged , Alcohol Drinking/psychology , Amputation, Surgical/psychology , Diabetes Mellitus, Type 2/physiopathology , Diabetes Mellitus, Type 2/psychology , Diabetic Foot/physiopathology , Diabetic Foot/psychology , Diabetic Neuropathies/complications , Diabetic Neuropathies/physiopathology , Female , Germany/epidemiology , Humans , Male , Middle Aged , Patient Compliance/statistics & numerical data , Risk Factors , Surveys and Questionnaires
9.
Herzschrittmacherther Elektrophysiol ; 21(4): 228-38, 2010 Dec.
Article in German | MEDLINE | ID: mdl-21113605

ABSTRACT

Class I antiarrhythmic drugs are sodium channel inhibitors that act by slowing myocardial conduction and, thus, interrupting or preventing reentrant arrhythmia. Due to proarrhythmic effects and the risk of ventricular tachyarrhythmia, class I antiarrhythmics should not be administered in patients with structural heart disease. Nevertheless, there remains a broad spectrum of arrhythmias--among the most common being atrial fibrillation--that can successfully be treated with class I antiarrhythmic drugs. This review gives an overview on the classification, antiarrhythmic mechanisms, indications, side effects, and application modes of class I antiarrhythmic drugs.


Subject(s)
Anti-Arrhythmia Agents/classification , Anti-Arrhythmia Agents/therapeutic use , Arrhythmias, Cardiac/drug therapy , Sodium Channel Blockers/classification , Sodium Channel Blockers/therapeutic use , Administration, Oral , Adrenergic beta-Antagonists/therapeutic use , Anti-Arrhythmia Agents/adverse effects , Arrhythmias, Cardiac/chemically induced , Arrhythmias, Cardiac/mortality , Atrial Fibrillation/drug therapy , Atrial Fibrillation/mortality , Contraindications , Dose-Response Relationship, Drug , Drug Therapy, Combination , Electrocardiography/drug effects , Female , Heart Failure/complications , Heart Failure/drug therapy , Humans , Infusions, Intravenous , Myocardial Infarction/complications , Myocardial Infarction/drug therapy , Pregnancy , Randomized Controlled Trials as Topic , Sodium Channel Blockers/adverse effects , Tachycardia, Atrioventricular Nodal Reentry/drug therapy , Tachycardia, Supraventricular/drug therapy , Tachycardia, Ventricular/drug therapy
10.
J Psychosom Obstet Gynaecol ; 29(4): 280-9, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19065397

ABSTRACT

OBJECTIVE: The aim of this study is to explore the wish of gynecological and obstetric inpatients to attend psychosomatic services. Predictors influencing this wish are evaluated. METHOD: Three groups of patients participated in the study. The groups consisted of patients diagnosed with malignant gynecological diseases (n = 175), benign gynecological diseases (n = 302), and obstetric diseases (n = 238). The following domains were assessed in a cross-sectional design: symptoms of anxiety and depression (HADS), physical complaints (GBB-24), health-related quality of life (SF-12), and the wish to attend psychosomatic services. RESULTS: 34% of the participants indicated that they wanted to attend psychosomatic services during their stay in the hospital. The group of patients diagnosed with malignant gynecological diseases had the highest proportion of women who stated that wish (43%). Multiple logistic regression models showed that former psychotherapeutic experiences as well as low psychological quality of life predicted the wish to attend psychosomatic services in patients diagnosed with malignant gynecological or obstetric diseases. CONCLUSION: It was shown that a considerable proportion of patients wanted to attend psychosomatic care during their hospitalization. Contrary to physical and sociodemographic variables, psychological factors were significant predictors of the inpatient's wish to attend psychosomatic services. This suggests that the subjective estimation of impairments is a major predictor of the wish to attend psychosomatic care.


Subject(s)
Genital Diseases, Female/psychology , Genital Neoplasms, Female/psychology , Patient Satisfaction , Pregnancy Complications/psychology , Psychophysiologic Disorders/therapy , Adult , Female , Genital Diseases, Female/therapy , Genital Neoplasms, Female/therapy , Germany , Humans , Logistic Models , Middle Aged , Multivariate Analysis , Pregnancy , Pregnancy Complications/therapy , Psychophysiologic Disorders/psychology , Psychosomatic Medicine
11.
J Phys Chem B ; 109(1): 230-9, 2005 Jan 13.
Article in English | MEDLINE | ID: mdl-16851009

ABSTRACT

CdS/dendrimer nanocomposites can be synthesized from methanolic Cd(2+) and S(2-) with amine-terminated polyamidoamine dendrimers of generation 8 (G8NH(2)) as stabilizers. By controlling the preparation conditions, nanoparticles with diameters < or = 2 nm can be obtained with a narrow size distribution. They show blue photoluminescence at approximately 450 nm. We studied the effects of various additives on the photoluminescence and elucidated its mechanism. Stable aggregates of two to three G8NH(2) molecules with several CdS nanoparticles form; the particles are located at the surface of the G8NH(2) molecules. The adsorption of the CdS/G8NH(2) nanocomposites on flat substrate surfaces is determined by the substrate chemistry. The hydrophilic nature of G8NH(2) results in weak affinity to graphite but strong affinity to hydroxy-terminated substrates such as mica, oxidized silicon wafers, and carboxylate-terminated monolayers. Patterning of nanocomposites on these hydrophilic substrates is achieved by the microcontact printing method. We propose to use only one molecule, a large dendrimer, to control the nanoparticle formation and also the immobilization of the synthesized nanoparticle/dendrimer composites.


Subject(s)
Cadmium Compounds/chemistry , Cadmium Compounds/chemical synthesis , Dendrimers/chemistry , Dendrimers/chemical synthesis , Nanostructures/chemistry , Sulfides/chemistry , Sulfides/chemical synthesis , Adsorption , Luminescence , Particle Size , Photochemistry
12.
Langmuir ; 20(2): 441-7, 2004 Jan 20.
Article in English | MEDLINE | ID: mdl-15743089

ABSTRACT

We studied the adsorption behavior and surface chemistry of the tobacco mosaic virus (TMV) on well-defined metal and insulator surfaces. TMV serves as a tubular supramolecular model system with precisely known surface termination. We show that if the surface chemistry of the substrate and the pH-dependent chemistry of the molecular surface match, for example, by hydrogen bonding, a strong adsorption occurs, and lateral movement is impeded. Due to the immobilization, the virion can be imaged by atomic force microscopy (AFM) in contact mode. We also used self-assembled monolayers with an acyl chloride group to induce covalent bonding via ester formation. Noncontact AFM proved that TMV keeps its cylindrical cross section only under weak adsorption conditions, that is, on hydrophobic surfaces, while on hydrophilic substrates a deformation occurs to maximize the number of interacting chemical groups.


Subject(s)
Tobacco Mosaic Virus/chemistry , Adsorption , Binding Sites , Hydrogen Bonding , Hydrogen-Ion Concentration , Microscopy, Atomic Force , Microscopy, Electron , Surface Properties , Tobacco Mosaic Virus/ultrastructure
13.
Proc Natl Acad Sci U S A ; 98(13): 7140-5, 2001 Jun 19.
Article in English | MEDLINE | ID: mdl-11390970

ABSTRACT

Human cytomegalovirus (HCMV) infection alters the expression of many cellular genes, including IFN-stimulated genes (ISGs) [Zhu, H., Cong, J.-P., Mamtora, G., Gingeras, T. & Shenk, T. (1998) Proc. Natl. Acad. Sci. USA 95, 14470-14475]. By using high-density cDNA microarrays, we show that the HCMV-regulated gene expression profile in fibroblasts does not differ substantially from the response generated by IFN. Furthermore, we identified the specific viral component triggering this response as the envelope glycoprotein B (gB). Cells treated with gB, but not other herpesviral glycoproteins, exhibited the same transcriptional profile as HCMV-infected cells. Thus, the interaction of gB with its as yet unidentified cellular receptor is the principal mechanism by which HCMV alters cellular gene expression early during infection. These findings highlight a pioneering paradigm for the consequences of virus-receptor interactions.


Subject(s)
Cytomegalovirus/genetics , Gene Expression Regulation , Interferon-gamma/pharmacology , Transcription, Genetic , Viral Envelope Proteins/metabolism , Fibroblasts/cytology , Fibroblasts/drug effects , Fibroblasts/metabolism , Gene Expression Regulation/drug effects , Humans , Infant, Newborn , Male , Molecular Sequence Data , Oligonucleotide Array Sequence Analysis , Recombinant Proteins , Skin , Transcription, Genetic/drug effects , Transfection , Viral Envelope Proteins/genetics
15.
Clin Chem Lab Med ; 38(2): 137-45, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10834401

ABSTRACT

An important class of substances in clinical chemistry are metabolites in body fluids, which are accessible by near-infrared spectroscopy without sample treatment using reagentless, fast and readily automated in vitro assays. Furthermore, noninvasive sensing systems are under development for the determination of blood glucose, especially for diabetic patients or for monitoring in intensive care and surgery. Near-infrared diffuse reflectance spectrometry of skin was employed allowing a certain tissue volume to be integrally probed. For calibration, the partial least-squares (PLS) algorithm was used either based on wide spectral intervals or using special spectral variable selection. Capillary blood glucose reference concentrations were obtained by finger pricking and an automated laboratory method (hexokinase/G6P-DH). Clear evidence is provided for the physical effect, as manifested by the spectral glucose absorptivities, underlying the individual single-person calibration models, which still require improvements in the methodology in the normo- and hypoglycemic concentration range. In extending the potential of noninvasive blood assays by infrared spectroscopy, a novel technique is presented for probing the intravascular fluid space by using fast spectral near-infrared measurements of skin tissue. The pulsatile blood spectrum can be derived from reflectance spectra of oral mucosa by Fourier analysis (near-infrared plethysmography). Future applications and prospects for noninvasive blood assays are discussed.


Subject(s)
Body Fluids/metabolism , Monitoring, Physiologic/methods , Spectroscopy, Near-Infrared/methods , Algorithms , Blood Glucose/analysis , Blood Glucose Self-Monitoring/methods , Humans , Least-Squares Analysis , Monitoring, Physiologic/standards , Plethysmography/methods , Skin/blood supply , Skin/metabolism , Spectroscopy, Near-Infrared/standards
16.
J Virol ; 73(7): 5757-66, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10364327

ABSTRACT

We describe, for the first time, the generation of a viral DNA chip for simultaneous expression measurements of nearly all known open reading frames (ORFs) in the largest member of the herpesvirus family, human cytomegalovirus (HCMV). In this study, an HCMV chip was fabricated and used to characterize the temporal class of viral gene expression. The viral chip is composed of microarrays of viral DNA prepared by robotic deposition of oligonucleotides on glass for ORFs in the HCMV genome. Viral gene expression was monitored by hybridization to the oligonucleotide microarrays with fluorescently labelled cDNAs prepared from mock-infected or infected human foreskin fibroblast cells. By using cycloheximide and ganciclovir to block de novo viral protein synthesis and viral DNA replication, respectively, the kinetic classes of array elements were classified. The expression profiles of known ORFs and many previously uncharacterized ORFs provided a temporal map of immediate-early (alpha), early (beta), early-late (gamma1), and late (gamma2) genes in the entire genome of HCMV. Sequence compositional analysis of the 5' noncoding DNA sequences of the temporal classes, performed by using algorithms that automatically search for defined and recurring motifs in unaligned sequences, indicated the presence of potential regulatory motifs for beta, gamma1, and gamma2 genes. In summary, these fabricated microarrays of viral DNA allow rapid and parallel analysis of gene expression at the whole viral genome level. The viral chip approach coupled with global biochemical and genetic strategies should greatly speed the functional analysis of established as well as newly discovered large viral genomes.


Subject(s)
Cytomegalovirus/genetics , DNA, Viral/analysis , Genome, Viral , Oligonucleotide Array Sequence Analysis , Base Sequence , Cell Line , Gene Expression/drug effects , Humans , Kinetics , Molecular Sequence Data
18.
FASEB J ; 12(11): 971-80, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9707169

ABSTRACT

Potential toxicity from exposure to mercury vapor (Hg(o)) from dental amalgam fillings is the subject of current public health debate in many countries. We evaluated potential central nervous system (CNS) toxicity associated with handling Hg-containing amalgam materials among dental personnel with very low levels of Hg(o) exposure (i.e., urinary Hg <4 microg/l), applying a neurobehavioral test battery to evaluate CNS functions in relation to both recent exposure and Hg body burden. New distinctions between subtle preclinical effects on symptoms, mood, motor function, and cognition were found associated with Hg body burden as compared with those associated with recent exposure. The pattern of results, comparable to findings previously reported among subjects with urinary Hg >50 microg/l, presents convincing new evidence of adverse behavioral effects associated with low Hg(o) exposures within the range of that received by the general population.


Subject(s)
Brain/drug effects , Dental Amalgam/adverse effects , Dental Assistants , Dentists , Mercury/adverse effects , Occupational Exposure/adverse effects , Affect , Cognition , Female , Humans , Male , Mercury/urine , Middle Aged , Motor Activity
19.
Neurotoxicol Teratol ; 20(4): 429-39, 1998.
Article in English | MEDLINE | ID: mdl-9697969

ABSTRACT

A Across-study design was used to evaluate the sensitivities of five psychomotor tasks previously used to assess preclinical effects of low-level Hg0 (urinary < or =55 microg/l). Pooling dental professional subject populations from six studies conducted over the last 6 years, a larger study population was obtained with a high degree of uniformity (N = 230). The five psychomotor tests were: Intentional Hand Steadiness Test (IHST); Finger Tapping: The One-Hole Test: NES Simple Reaction Time (SRT); and Hand Tremor. Multivariate analyses were conducted following the hierarchical analysis of multiple responses (HAMR) approach. First, multiple scores of each test were combined into a single-factor (or related summary) variable and its reliability was estimated. Second. multiple regression analyses were conducted including log-transformed [Hg0]U levels, age, gender, and alcohol consumption in each model. Computed were both B and bu, the magnitudes of the log-Hg0 standardized coefficient. respectively uncorrected and corrected for dependent variable attenuation due to unreliability. Results indicated remarkable differences in the effects of relative level of Hg0 on psychomotor performance. Significant associations were found for the IHST factor (B = 0.415, p < 10(-6)), followed by finger tapping, which was relatively meager and insignificant (B 0.141, p = 0.17). The IHST results hold the greatest occupational relevance for dental professionals who rely on manual dexterity in restorative dentistry. Further, this statistical approach is recommended in future studies for condensation of multiple scores into summary scores with enhanced reliabilities useful in correcting for attenuation relationships (B(u)s) with exposure levels.


Subject(s)
Dentistry , Mercury/adverse effects , Psychomotor Performance/drug effects , Adult , Aged , Dose-Response Relationship, Drug , Evaluation Studies as Topic , Female , Fingers/innervation , Hand/innervation , Humans , Male , Middle Aged , Neuropsychological Tests , Reaction Time/drug effects , Reproducibility of Results , Sensitivity and Specificity , Tremor/chemically induced , Workforce
20.
Neurotoxicol Teratol ; 18(4): 401-6, 1996.
Article in English | MEDLINE | ID: mdl-8866530

ABSTRACT

Neurobehavioral studies often employ test batteries and confront issues of multiple testing and comparability between batteries. We have organized our battery of 12 tests into areas of neurobehavioral function to reduce the number of reported results, provide greater statistical power, and improve interpretability of the results. We explored several different organizational and statistical methods of creating summary scores including a priori groupings based upon clinical experience and factor analysis. We compared the sensitivity of these summary scores to performance changes associated with exposure to styrene in the manufacture of reinforced plastics. Our results demonstrated dramatic increases in power to detect exposure related changes compared to using individual test scores. Furthermore, the various methods provided generally compatible and comparable results. We encourage other neurobehavioral investigators to pursue and refine this approach.


Subject(s)
Diagnosis, Computer-Assisted/instrumentation , Neuropsychological Tests , Occupational Exposure , Adolescent , Adult , Aged , Attention/drug effects , Cognition/physiology , Diagnosis, Computer-Assisted/methods , Factor Analysis, Statistical , Female , Humans , Male , Memory/drug effects , Middle Aged , Psychomotor Performance/drug effects , Visual Perception/drug effects
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