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1.
NPJ Genom Med ; 4: 21, 2019.
Article in English | MEDLINE | ID: mdl-31508243

ABSTRACT

Doubts have been raised about the value of DNA-based screening for low-prevalence monogenic conditions following reports of testing this approach using available electronic health record (EHR) as the sole phenotyping source. We hypothesized that a better model for EHR-focused examination of DNA-based screening is Cystic Fibrosis (CF) since the diagnosis is proactively sought within the healthcare system. We reviewed CFTR variants in 50,778 exomes. In 24 cases with bi-allelic pathogenic CFTR variants, there were 21 true-positives. We considered three cases "potential" false-positives due to limitations in available EHR phenotype data. This genomic screening exhibited a positive predictive value of 87.5%, negative predictive value of 99.9%, sensitivity of 95.5%, and a specificity of 99.9%. Despite EHR-based phenotyping limitations in three cases, the presence or absence of pathogenic CFTR variants has strong predictive value for CF diagnosis when EHR data is used as the sole phenotyping source. Accurate ascertainment of the predictive value of DNA-based screening requires condition-specific phenotyping beyond available EHR data.

2.
Transl Psychiatry ; 7(9): e1236, 2017 09 19.
Article in English | MEDLINE | ID: mdl-28926003

ABSTRACT

Previous research suggests that age of first exposure (AFE) to football before age 12 may have long-term clinical implications; however, this relationship has only been examined in small samples of former professional football players. We examined the association between AFE to football and behavior, mood and cognition in a large cohort of former amateur and professional football players. The sample included 214 former football players without other contact sport history. Participants completed the Brief Test of Adult Cognition by Telephone (BTACT), and self-reported measures of executive function and behavioral regulation (Behavior Rating Inventory of Executive Function-Adult Version Metacognition Index (MI), Behavioral Regulation Index (BRI)), depression (Center for Epidemiologic Studies Depression Scale (CES-D)) and apathy (Apathy Evaluation Scale (AES)). Outcomes were continuous and dichotomized as clinically impaired. AFE was dichotomized into <12 and ⩾12, and examined continuously. Multivariate mixed-effect regressions controlling for age, education and duration of play showed AFE to football before age 12 corresponded with >2 × increased odds for clinically impaired scores on all measures but BTACT: (odds ratio (OR), 95% confidence interval (CI): BRI, 2.16,1.19-3.91; MI, 2.10,1.17-3.76; CES-D, 3.08,1.65-5.76; AES, 2.39,1.32-4.32). Younger AFE predicted increased odds for clinical impairment on the AES (OR, 95% CI: 0.86, 0.76-0.97) and CES-D (OR, 95% CI: 0.85, 0.74-0.97). There was no interaction between AFE and highest level of play. Younger AFE to football, before age 12 in particular, was associated with increased odds for impairment in self-reported neuropsychiatric and executive function in 214 former American football players. Longitudinal studies will inform youth football policy and safety decisions.


Subject(s)
Apathy/physiology , Athletic Injuries/complications , Brain Injuries, Traumatic/complications , Cognitive Dysfunction/etiology , Depression/etiology , Executive Function/physiology , Football , Metacognition/physiology , Self-Control , Adult , Age Factors , Aged , Brain Injuries, Traumatic/etiology , Humans , Male , Middle Aged
3.
Neuroimage Clin ; 11: 398-407, 2016.
Article in English | MEDLINE | ID: mdl-27077023

ABSTRACT

Functional networks in resting-state fMRI are identified by characteristics of their intrinsic low-frequency oscillations, more specifically in terms of their synchronicity. With advanced aging and in clinical populations, this synchronicity among functionally linked regions is known to decrease and become disrupted, which may be associated with observed cognitive and behavioral changes. Previous work from our group has revealed that oscillations within the slow-5 frequency range (0.01-0.027 Hz) are particularly susceptible to disruptions in aging and following a stroke. In this study, we characterized longitudinally the changes in the slow-5 oscillations in stroke patients across two different time-points. We followed a group of ischemic stroke patients (n = 20) and another group of healthy older adults (n = 14) over two visits separated by a minimum of three months (average of 9 months). For the stroke patients, one visit occurred in their subacute window (10 days to 6 months after stroke onset), the other took place in their chronic window (> 6 months after stroke). Using a mid-order group ICA method on 10-minutes eyes-closed resting-state fMRI data, we assessed the frequency distributions of a component's representative time-courses for differences in regards to slow-5 spectral power. First, our stroke patients, in their subacute stage, exhibited lower amplitude slow-5 oscillations in comparison to their healthy counterparts. Second, over time in their chronic stage, those same patients showed a recovery of those oscillations, reaching near equivalence to the healthy older adult group. Our results indicate the possibility of an eventual recovery of those initially disrupted network oscillations to a near-normal level, providing potentially a biomarker for stroke recovery of the cortical system. This finding opens new avenues in infra-slow oscillation research and could serve as a useful biomarker in future treatments aimed at recovery.


Subject(s)
Brain Waves/physiology , Recovery of Function/physiology , Stroke/physiopathology , Aged , Electroencephalography , Female , Humans , Image Processing, Computer-Assisted , Longitudinal Studies , Magnetic Resonance Imaging , Male , Middle Aged , Oxygen/blood , Stroke/diagnostic imaging , Time Factors
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(5 Pt 2): 056307, 2012 May.
Article in English | MEDLINE | ID: mdl-23004862

ABSTRACT

We report the results of an experimental study on the multiplicity of states in Taylor-Couette flow as a result of axial localization of azimuthally rotating waves. Localized states have been found to appear hysteretically from time-dependent Taylor-Couette flow at Reynolds numbers significantly above the onset of wavy Taylor vortices. These localized states have the shape of a modulated rotating wave and differ significantly from global modulated wavy Taylor vortex states in their spatial characteristics. Axial localization of rotating waves is accompanied with a significant increase in size of the underlying pair of Taylor vortices. Our work reveals that localization provides a mechanism for the appearance of multiple time-dependent states in Taylor-Couette flow.

5.
Caries Res ; 46(4): 413-23, 2012.
Article in English | MEDLINE | ID: mdl-22710271

ABSTRACT

Over the past 5-10 years, zero-inflated (ZI) count regression models have been increasingly applied to the analysis of dental caries indices (e.g. DMFT, dfms). The main reason for that is linked to the broad decline in children's caries experience, such that dmf and DMF indices more frequently generate low or even zero counts. This article specifically reviews the application of ZI Poisson and ZI negative binomial regression models to dental caries, with emphasis on the description of the models and the interpretation of fitted model results given the study goals. The review finds that interpretations provided in the published caries research are often imprecise or inadvertently misleading, particularly with respect to failing to discriminate between inference for the class of susceptible persons defined by such models and inference for the sampled population in terms of overall exposure effects. Recommendations are provided to enhance the use as well as the interpretation and reporting of results of count regression models when applied to epidemiological studies of dental caries.


Subject(s)
DMF Index , Dental Caries/epidemiology , Binomial Distribution , Epidemiologic Studies , Humans , Incidence , Poisson Distribution , Prevalence , Regression Analysis
8.
Eur J Dent Educ ; 12 Suppl 1: 64-73, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18289269

ABSTRACT

The ultimate purpose of both dental industry and dental education is to improve the oral health of the public. This report provides background information on the different roles and objectives of the dental industry and dental education communities, the different operating environment of each sector and also areas of common interest where collaboration will be of mutual benefit. The report addresses five areas for potential collaboration between the dental industry and the dental education communities: 1. Contribution to joint activities. 2. Effectiveness and efficiency. 3. Workforce needs. 4. Middle- and low-income countries. 5. The future of International Federation of Dental Educators and Associations (IFDEA). The traditional areas of support and their limitations that have been provided by industry are outlined in the report and some new approaches for collaboration are considered. Industry-based research has been an important factor in developing new products and technologies and in promoting oral health. However there is a need to facilitate the introduction of these developments at an early stage in the education process. Industry has to operate in an efficient manner to remain competitive and maximise its returns and therefore survive. The academic sector operates in a different environment and under different governance structures; although some trends are noted towards adoption of greater efficiency and financial accountability similar to industry. Opportunities to jointly develop best business practices should be explored. Industry has responded well to the oral health needs of the public through the development of new products and technologies. The education community needs to respond in a similar way by examining different healthcare delivery models worldwide and developing programmes to train members of the dental team to cater for future needs and demands of communities in different regions of the world. The reputation of industry-based scientists and clinicians is high, and their role in contributing to the dental education process in practical ways needs to be explored and further developed. Closer relationships between industry scientists and faculty and students could assist industrys need and desire to develop new technologies for the broader dental care system. The corporate sector can play a key role in the future success of IFDEA by providing support and expertise in developing areas such as regional leadership institutes, a Global Faculty and Network and in collaborating in developing continuing education programmes as well as involvement in its governance. Thirteen recommendations are made in the report. These are considered to be important initial steps in developing the already strong relationship between the education and corporate sectors. Partnership and collaborating more effectively along the lines suggested should, almost certainly, generate mutually beneficial outcomes, whilst serving over the long term to elevate the publics oral health status on a global basis.


Subject(s)
Cooperative Behavior , Education, Dental , Health Care Sector , Interinstitutional Relations , Oral Health , Delivery of Health Care , Dental Care , Dentistry , Developing Countries , Education, Dental, Continuing , Efficiency , Health Care Sector/organization & administration , Health Promotion , Health Services Needs and Demand , Humans , Information Dissemination , Leadership , Private Sector , Research Support as Topic , Societies, Dental , Technology, Dental , Training Support , Workforce
9.
Clin Res Cardiol ; 95 Suppl 2: II16-18, 2006 Jan.
Article in German | MEDLINE | ID: mdl-16598564

ABSTRACT

From the view of one of the largest public health insurance companies, in this paper it is outlined that Integrated Health Care provides opportunities to influence the largely regional structures of health care supply. This insurance company has specialized in contracts for Integrated Health Care in cardiology in order to achieve sustainable solutions for all providers of invasive and interventional cardiology that are economically reasonable. But first of all, only evidence-based medical procedures and interventions based on clinical pathways are eligible for the contracts of this company. In outlining this, it becomes evident that by far not all German public health insurance companies have yet used their opportunity.


Subject(s)
Cardiology/trends , Delivery of Health Care, Integrated/organization & administration , Insurance, Health/trends , Cardiology/economics , Cardiology/standards , Delivery of Health Care, Integrated/economics , Delivery of Health Care, Integrated/standards , Family Practice , Germany , Humans , Insurance, Health/economics , Insurance, Major Medical/economics , Insurance, Major Medical/trends , Marketing of Health Services/economics , National Health Programs/economics , Quality of Health Care
10.
Z Kardiol ; 94 Suppl 4: IV/4-6, 2005.
Article in German | MEDLINE | ID: mdl-16416063

ABSTRACT

The legal framework for Integrated Health Care since 2004 offers many opportunities for health professionals and insurers in the competition for "high quality care". Germany's largest statutory health insurance fund, BARMER, has already developed around 100 Integrated Health Care Projects for a wide range of conditions. One important issue is the relationship to disease management programs. Our program "integrated cardiological care" combines both DMP and integrated health care and thus already shows good results with respect to patient acceptance as well as savings trough the changing patterns in interventional cardiology.


Subject(s)
Cardiology/organization & administration , Delivery of Health Care, Integrated/organization & administration , Health Plan Implementation/organization & administration , National Health Programs/organization & administration , Cardiology/economics , Cost Savings/trends , Delivery of Health Care, Integrated/economics , Disease Management , Economic Competition/economics , Economic Competition/organization & administration , Forecasting , Germany , Health Plan Implementation/economics , Humans , National Health Programs/economics , Physician-Patient Relations , Quality Assurance, Health Care/economics , Quality Assurance, Health Care/organization & administration
11.
J Dent Res ; 83 Spec No C: C6-14, 2004.
Article in English | MEDLINE | ID: mdl-15286114

ABSTRACT

The history of clinical trials would include events in 1747 on board the Salisbury, a British Navy vessel at sea with 12 seamen critically ill with scurvy. Involving these 12 sailors in a study, an officer on board by the name of Lind evaluated six potential treatments for scurvy, and rapidly reached the conclusion that daily consumption of citrus fruits returned the men fit for duty in approximately six days (Bull, 1959). The concept of experimental randomization was first developed by Sir R.A. Fisher (1925, 1926), and the method was introduced to medical research via a study of tuberculosis treatment by Amberson and co-workers (1931), who randomized 24 TB patients into two groups, one to receive the experimental therapy, the other serving as the control. Amberson et al. also incorporated the concept of blinding into their study. Sir Austin Bradford Hill codified and built on the principles of scientific experimentation developed by Fisher, and introduced the use of random numbers in the allocation of patients in the British Medical Research Council (1948) study of the effect of streptomycin in the treatment of tuberculosis (Daniels and Hill, 1952; Hill, 1952). The first applications of clinical trial methodology for testing interventions on dental, oral, and maxillofacial diseases and conditions are more difficult to determine. For dental caries prevention, however, Chilton and Fertig (1958) and Slack and Martin (1964) were certainly among the early caries clinical trial pioneers. As clinical trials have come into the mainstream of clinical research in medicine and dentistry, a great deal of developmental work has focused on their methodological enhancement. The most successful of these efforts have come from fruitful, ongoing collaborations among clinician investigators, biostatisticians, data management specialists, biomedical ethicists, and others with an academic interest in clinical trial design and utilization. During the past 25 years, the emergence of systematic reviews and the evidence-based medicine (EBM) movement have also contributed significantly to the increasing reliance on randomized clinical trial outcomes for the advancement of better clinical practice (Richards et al., 1997; Straus and Sackett, 1998; www.cochrane.org/cochrane/ccbroch.htm#BDL, 2002).


Subject(s)
Clinical Trials as Topic , Dental Caries/prevention & control , Clinical Trials as Topic/classification , Clinical Trials as Topic/ethics , Clinical Trials as Topic/methods , Humans , Meta-Analysis as Topic , Multicenter Studies as Topic , Randomized Controlled Trials as Topic , Research Design
13.
Biochemistry ; 39(35): 10892-7, 2000 Sep 05.
Article in English | MEDLINE | ID: mdl-10978176

ABSTRACT

Chemical synthesis, functional reconstitution, and electron paramagnetic resonance (EPR) have been used to analyze the structure and function of phospholamban (PLB), a 52-residue integral membrane protein that regulates the calcium pump (Ca-ATPase) in cardiac sarcoplasmic reticulum (SR). PLB exists in equilibrium between monomeric and pentameric forms, as observed by SDS-PAGE, EPR, and fluorescence. It has been proposed that inhibition of the pump is due primarily to the monomeric form, with both pentameric stability and inhibition dependent primarily on the transmembrane (TM) domain. To test these hypotheses, we have studied the physical and functional properties of a synthetic null-cysteine PLB analogue that is entirely monomeric on SDS-PAGE, and compared it with the synthetic null-cysteine TM domain (residues 26-52). The TM domain was found to be primarily oligomeric on SDS-PAGE, and boundary lipid spin label analysis in lipid bilayers verified that the isolated TM domain is more oligomeric than the full-length parent molecule. These results indicate that the stability of the PLB pentamer is due primarily to attractive interactions between hydrophobic TM domains, overcoming the repulsive electrostatic interactions between the cationic cytoplasmic domains (residues 1-25). When reconstituted into liposomes containing the Ca-ATPase, the null-cysteine TM domain had the same inhibitory function as that of the full-length parent molecule. We conclude that the TM domain of PLB is sufficient for inhibitory function, the oligomeric stability of PLB does not determine its inhibitory activity, and the three Cys residues in the TM domain are not required for inhibitory function.


Subject(s)
Calcium-Binding Proteins/chemistry , Calcium-Transporting ATPases/antagonists & inhibitors , Cysteine/chemistry , Enzyme Inhibitors/chemistry , Membrane Proteins/chemistry , Alanine/chemistry , Amino Acid Sequence , Amino Acid Substitution , Calcium-Binding Proteins/chemical synthesis , Calcium-Binding Proteins/pharmacology , Calcium-Transporting ATPases/chemistry , Electron Spin Resonance Spectroscopy , Electrophoresis, Polyacrylamide Gel , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacology , Lipid Bilayers/chemistry , Membrane Proteins/pharmacology , Molecular Sequence Data , Molecular Weight , Peptide Fragments/chemistry , Peptide Fragments/pharmacology , Phosphatidylcholines/chemistry , Protein Structure, Tertiary , Structure-Activity Relationship
14.
Wound Repair Regen ; 8(2): 103-9, 2000.
Article in English | MEDLINE | ID: mdl-10810036

ABSTRACT

Chronic abdominal sepsis is associated with impaired tissue repair. Treatment of burn patients with growth hormone results in improved healing of skin graft donor sites. The goal of this study was to determine whether administration of growth hormone could attenuate the inhibitory effects of sepsis on cutaneous wound healing. Four groups of male Sprague Dawley rats were studied: control, control + growth hormone, sepsis, and sepsis + growth hormone. Sepsis was caused by implantation of a bacterial focus in the peritoneal cavity. Control animals underwent sham laparotomy, and polyvinyl alcohol sponge implants were placed in subdermal pockets in all animals. Saline or growth hormone (400 microg) was injected subcutaneously every 12 hours. On day 5, the incisional wounds and polyvinyl alcohol sponge implants were harvested. The breaking strength of abdominal incisions was measured. Granulation tissue penetration and quality were determined by scoring polyvinyl alcohol sponge implant histology from 1 to 4 in a blinded fashion. Collagen deposition in polyvinyl alcohol sponge implants was quantitated by hydroxyproline assay. Septic mortality was not altered by growth hormone administration. Septic animals showed a reduction in food consumption for 2 days after surgery (p < 0.05 vs. controls), which was not affected by growth hormone administration. The breaking strength of incisional wounds and hydroxyproline content of polyvinyl alcohol sponge implants was reduced in septic rats (p < 0.001 vs. controls) but administration of growth hormone for 5 days did not improve breaking strength or collagen deposition in either group. We conclude that the administration of growth hormone for 5 days did not improve collagen deposition or breaking strength in cutaneous wounds from control or septic animals. The results suggest that growth hormone treatment is unlikely to improve tissue repair in sepsis-induced catabolic illness.


Subject(s)
Growth Hormone/administration & dosage , Sepsis/drug therapy , Skin/injuries , Wound Healing/drug effects , Wounds and Injuries/drug therapy , Animals , Chronic Disease , Disease Models, Animal , Dose-Response Relationship, Drug , Injections, Subcutaneous , Insulin-Like Growth Factor I/analysis , Male , Radioimmunoassay , Random Allocation , Rats , Rats, Sprague-Dawley , Reference Values , Sepsis/diagnosis , Sepsis/microbiology , Treatment Outcome , Wound Healing/physiology , Wounds and Injuries/microbiology
16.
Biochemistry ; 37(35): 12074-81, 1998 Sep 01.
Article in English | MEDLINE | ID: mdl-9724519

ABSTRACT

To test models for the pentameric structure of phospholamban (PLB) and study its structure and molecular dynamics in SDS solution, we characterized recombinant PLB and several of its mutants by (a) reactivity of cysteine residues toward DTNB [5, 5'-dithiobis(2-nitrobenzoic acid)] and a thiol-reactive spin label, (b) oligomeric state on SDS-PAGE, and (c) EPR of the spin-labeled proteins. WT-PLB has three cysteine residues (36, 41, and 46), all located in the hydrophobic C-terminal transmembrane region. In SDS at pH 7.5, exhaustive reaction with either sulfhydryl reagent resulted in essentially 2 mol of cysteine reacted/mol of WT-PLB, with only slight destabilization of the native pentameric structure. When WT-PLB was denatured in guanidine at pH 8.1, all three cysteines reacted, disrupting the pentamer, which was restored upon cleavage of the disulfide bonds with DTT. In the tetrameric mutant C41L-PLB, the two remaining cysteine residues reacted, reversibly destabilizing the tetramer. In the monomeric mutant L37A-PLB, all three cysteines reacted. The pentameric double cysteine replacement mutant C36,46A-PLB showed negligible reactivity. We conclude that Cys-41 is the unreactive cysteine in PLB and is located at a crucial site for the maintenance of the pentameric structure. EPR spectra in SDS of spin-labeled WT-PLB and mutants correlate with the oligomeric state on SDS-PAGE; oligomeric proteins show decreased spin-label mobility compared with monomers. Molecular dynamics calculations were used to construct an atomic model for the transmembrane region of the PLB pentamer, constrained by previous mutagenesis results and the results of the present study. We conclude that (a) the mobilities of spin-labels attached to PLB and its mutants are sensitive to oligomeric state and (b) the pattern of cysteine reactivity, spin-label mobility, and oligomeric state supports a structural model for the PLB pentamer in which interactions between each pair of subunits are stabilized by a leucine-isoleucine zipper.


Subject(s)
Calcium-Binding Proteins/chemistry , Calcium-Binding Proteins/genetics , Cysteine/chemistry , Cysteine/genetics , Animals , Calcium-Transporting ATPases/chemistry , Dithionitrobenzoic Acid/chemistry , Electron Spin Resonance Spectroscopy , Electrophoresis, Polyacrylamide Gel , Isoleucine/genetics , Leucine/genetics , Mesylates/chemistry , Models, Molecular , Mutagenesis, Site-Directed , Protein Structure, Tertiary , Spin Labels , Spodoptera , Sulfhydryl Compounds/chemistry
17.
Ann N Y Acad Sci ; 853: 186-94, 1998 Sep 16.
Article in English | MEDLINE | ID: mdl-10603946

ABSTRACT

In order to test molecular models of cardiac calcium transport regulation, we have used spectroscopy to probe the structures, dynamics, and interactions of the Ca pump (Ca-ATPase) and phospholamban (PLB) in cardiac sarcoplasmic reticulum (SR) and in reconstituted membranes. Electron paramagnetic resonance (EPR) and phosphorescence of probes bound to the Ca pump show that the activity of the pump is quite sensitive to its oligomeric interactions. In cardiac SR, PLB aggregates and inhibits the pump, and both effects are reversed by PLB phosphorylation. Previous analyses of PLB's oligomeric state were only in detergent solutions, so we used EPR and fluorescence to determine the oligomeric structure of PLB in its native state in lipid bilayers. Wild-type PLB is primarily oligomeric in the membrane, while the mutant L37A-PLB is monomeric. For both proteins, phosphorylation shifts the dynamic monomer-oligomer equilibrium toward oligomers, and induces a similar structural change, as indicated by tyrosine fluorescence; yet L37A-PLB is more effective than wild-type PLB in inhibiting and aggregating the pump. Fluorescence energy transfer shows that the Ca pump increases the fraction of monomeric PLB, indicating that the pump preferentially binds monomeric PLB. These results support a reciprocal aggregation model for Ca pump regulation, in which the Ca pump is aggregated and inhibited by association with PLB monomers, and phosphorylation of PLB reverses these effects while decreasing the concentration of PLB monomers. To investigate the structure of the PLB pentamer in more detail, we measured the reactivities of cysteine residues in the transmembrane domain of PLB, and recorded EPR spectra of spin labels attached to these sites. These results support an atomic structural model, based on molecular dynamics simulations and mutagenesis studies, in which the PLB pentamer is stabilized by a leucine-isoleucine zipper within the transmembrane domain.


Subject(s)
Calcium-Binding Proteins/chemistry , Calcium-Binding Proteins/metabolism , Calcium-Transporting ATPases/chemistry , Calcium-Transporting ATPases/metabolism , Animals , Electron Spin Resonance Spectroscopy , Intracellular Membranes/metabolism , Models, Molecular , Myocardium/metabolism , Phosphorylation , Protein Conformation , Protein Structure, Quaternary , Sarcoplasmic Reticulum/metabolism , Spectrometry, Fluorescence
18.
Vet Q ; 17(1): 1-5, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7610549

ABSTRACT

The effects of sarafloxacin, a newly developed veterinary fluoroquinolone antimicrobial, on 15 strains of aerobic and anaerobic bacteria of human origin were assessed under simulated human gut conditions. An in vitro gut simulation model was designed to mimic the situation of sarafloxacin (free and bound to meat) passing through the human gastrointestinal tract. The survival of bacteria in the simulation model and any subsequent change in the sensitivity of isolates to sarafloxacin were measured. The inhibitory level of sarafloxacin for the tested bacteria was strain dependent. It appeared that in broth culture Escherichia coli isolates were sensitive to sarafloxacin concentrations 5-fold lower than the concentrations present in the simulated gut model, suggesting that sarafloxacin may be partially unavailable due to absorption to organic matter in the model. There was no significant observed change in the sarafloxacin sensitivity of the bacterial strains exposed to the compound in the model.


Subject(s)
Anti-Infective Agents/pharmacology , Bacteroides fragilis/drug effects , Bifidobacterium/drug effects , Ciprofloxacin/analogs & derivatives , Digestive System/microbiology , Escherichia coli/drug effects , Fluoroquinolones , Animals , Bacteroides fragilis/classification , Bifidobacterium/classification , Ciprofloxacin/pharmacology , Colony Count, Microbial , Digestive System/drug effects , Drug Evaluation, Preclinical/methods , Drug Evaluation, Preclinical/veterinary , Drug Residues , Escherichia coli/classification , Humans , Intestinal Mucosa/drug effects , Intestinal Mucosa/microbiology , Microbial Sensitivity Tests , Models, Biological
19.
Andrologia ; 27(1): 55-65, 1995.
Article in English | MEDLINE | ID: mdl-7755190

ABSTRACT

The scope of this study was to evaluate the accuracy, precision and specificity of the sperm concentration measurements by the Strömberg-Mika Cell Motion Analyser (SM-CMA). Our data show that the instrument generally underscores the sperm concentration and therefore the uncorrected measurements must be corrected by the operator using the 'mouse'-driven option. In terms of precision, the system appears to have an excellent internal precision whereas its repeatability is influenced by the sperm concentration, the sample's homogeneity and the correction of the raw data. In order to increase the system's repeatability, we suggest that sperm counts should be carried out in various fields of the counting chamber, and the mean of the corrected values be taken as representative of the sperm concentration in the ejaculate if the various measurements show a homogeneous (poissonian) distribution. The correction of the raw data with the 'mouse'-driven correction option was also shown to improve the system's reproducibility. Concerning specificity, our data evidenced that, without technical correction, the instrument failed to correctly classify certain spermatozoa as such, thereby grossly underscoring sperm counts. This finding was more evident at low sperm counts. Overall, the SM-CMA requires additional laboratory time but the corrected sperm counts are comparable to manual counts and semi-automated counts with the added option that it provides the andrologists with various motility characteristics not possible with the latter methodologies.


Subject(s)
Autoanalysis/instrumentation , Computers , Semen/cytology , Sperm Count , Autoanalysis/statistics & numerical data , Humans , Male , Reproducibility of Results , Sensitivity and Specificity
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