Your new practice resource: smilemichigan.com.
Explore the source record for details and available documents.
Consumer Advocacy↗
Biomedical subjects
J Mertens
Publications and source records attributed to J Mertens.
[Long-term outcome of frontal sinus surgery: comparison of extranasal and endonasal surgical techniques].
BACKGROUND: During the last decades rhinosurgery largely developed up to endonasal accesses. Meanwhile many of the new techniques are established, so that the outcome of traditional extranasal methods should be compared with those of endonasal accesses, in order to estimate the status and for critical consideration. METHODS: A retrospective analysis recorded the results of 236 patients, operated on primary frontal sinus disease 1985-1993. The records were consulted concerning inpatient treatment and outpatient aftercare during standardized paranasal sinus consulting hours. RESULTS: During the follow-up period (3-10 years) 8% of the patients underwent resurgery. The lowest revision rate was found after using endonasal technique (5.9%), compared with osteoclastic methods (Ritter-Jansen, Riedel: 10.6%). The domain of osteoplastic operations with a revision rate of 9.4% were fractures, osteomas and mucoceles, because of an impossible endonasal access. In decision on osteoclastic procedures, the already osteoclastically operated site was of prime importance, especially since 1990. CONCLUSION: Already during the early years endonasal techniques of paranasal sinus surgery showed better outcome than osteoclastic accesses. The analysis indicates that the change to endonasal functional paranasal sinus surgery is justified and should be kept up. The traditional methods still have their rare authorization in case of special indications, especially if an osteoclastic procedure has been carried out already.
Follow-Up Studies↗
[An aberrant course of the internal carotid artery].
Aberrant vascular courses of the A. carotis interna are extremely rare. They are usually combined with pulsatile symptoms. Missing symptoms are not proof of a non-existing aberration, though. A paracentesis in such a situation leads to an initially unstoppable bleeding from the tympanion and tuba. For this reason it is necessary to contemplate a vascular reason for the local findings preoperatively.
Carotid Artery, Internal↗
Acoustic rhinometry: validation by three-dimensionally reconstructed computer tomographic scans.
The aim of the present study was a validation of acoustic rhinometry (AR) by computed tomography (CT). Six healthy subjects were examined by CT and AR. The CT data were processed in a computer program (AutoCAD), and a virtual three-dimensional model of each nasal cavity was constructed. This model permitted an individual prediction of the center line of the sound wave propagation through the air volume of the nasal cavity with the cross-sectional areas oriented perpendicularly to this line. The area-distance curves derived from AR and CT were compared. Linear regression analysis revealed a reasonable agreement of AR and CT in the anterior nose below a mean of 6 cm distance from the nostrils [r = 0.839, P < 0.01, m = 1.123, b = -0.113 (AR = m x CT + b)]. The measuring accuracy using CT as gold standard revealed a mean error at the nasal valve of <0.01 cm(2) (4.52%) and at the nasal isthmus of 0.02 cm(2) (1. 87%). Beyond 6 cm, the correlation decreased (r = 0.419), and overestimation of the true area occurred (>100%). In conclusion, the measurements were reasonably accurate for diagnostic use up to the turbinate head region. Certain factors induce an overestimation of the true areas beyond this region. However, these factors are constant and reproducible in a single subject, and intraindividual comparative measurements are possible beyond the turbinate head region.
Acoustics↗
The outcome and cost of alcohol and drug treatment in an HMO: day hospital versus traditional outpatient regimens.
OBJECTIVE: To compare outcome and cost-effectiveness of the two primary addiction treatment options, day hospitals (DH) and traditional outpatient programs (OP) in a managed care organization, in a population large enough to examine patient subgroups. DATA SOURCES: Interviews with new admissions to a large HMO's chemical dependency program in Sacramento, California between April 1994 and April 1996, with follow-up interviews eight months later. Computerized utilization and cost data were collected from 1993 to 1997. STUDY DESIGN: Design was a randomized control trial of adult patients entering the HMO's alcohol and drug treatment program (N = 668). To examine the generalizability of findings as well as self-selection factors, we also studied patients presenting during the same period who were unable or unwilling to be randomized (N = 405). Baseline interviews characterized type of substance use, addiction severity, psychiatric status, and motivation. Follow-up interviews were conducted at eight months following intake. Breathanalysis and urinalysis were conducted. Program costs were calculated. DATA COLLECTION: Interview data were merged with computerized utilization and cost data. PRINCIPAL FINDINGS: Among randomized subjects, both study arms showed significant improvement in all drug and alcohol measures. There were no differences overall in outcomes between DH and OP, but DH subjects with midlevel psychiatric severity had significantly better outcomes, particularly in regard to alcohol abstinence (OR = 2.4; 95% CI = 1.2, 4.9). The average treatment costs were $1,640 and $895 for DH and OP programs, respectively. In the midlevel psychiatric severity group, the cost of obtaining an additional person abstinent from alcohol in the DH cohort was approximately $5,464. Among the 405 self-selected subjects, DH was related to abstinence (OR = 2.1; 95% CI = 1.3, 3.5). CONCLUSIONS: Although significant benefits of the DH program were not found in the randomized study, DH treatment was associated with better outcomes in the self-selected group. However, for subjects with mid-level psychiatric severity in both the randomized and self-selected samples, the DH program produced higher rates of abstention and was more cost-effective. Self-selection in studies that randomize patients to services requiring very different levels of commitment may be important in interpreting findings for clinical practice.
Adult↗
Demographic characteristics, life context, and patterns of substance use among alcohol-dependent treatment clients in a health maintenance organization.
BACKGROUND: Although individuals dependent only on alcohol and those dependent on both alcohol and drugs typically are not studied together in clinical trials, they are treated together in most treatment programs. In this study we compared epidemiological characteristics of the alcohol-only and alcohol-and-drug dependents in a treatment sample to assess differential treatment needs. METHOD: Patients admitted to treatment at a health maintenance organization's chemical dependency program were sampled and interviewed by using a structured questionnaire. The sample included 491 alcohol-only and 217 alcohol-and-drug dependents. Demographic characteristics, lifetime and current substance use, Addiction Severity Index composite scores, and DSM-IV criteria for alcohol and drug dependence were assessed at admission. RESULTS: The odds of alcohol-and-drug dependence were higher among males, African Americans (when compared with whites), those who were younger, and those with less than college education. The risk was also higher among those who initiated heavy drinking or drug use before the age of 18. Increased psychiatric and family/social problems also were associated with combined dependence. CONCLUSIONS: Even in this relatively homogeneous socioeconomic status population, demographic characteristics were important predictors of type of dependence. Treatment programs which provide services that address prevention and psychosocial problems should pay attention to age of initiation as well as psychiatric and social problems.
Adolescent↗
Phylogenetic analysis of the 16S rDNA of the cytoplasmic bacterium Wolbachia from the novel host Folsomia candida (Hexapoda, Collembola) and its implications for wolbachial taxonomy.
Wolbachia pipientis are intracellular, transovarially inherited alpha-Proteobacteria in invertebrates. Four major Wolbachia groups exist: A, B (contained in divergent arthropods), C and D (harbored by Nematoda). By means of transmission electron microscopy, we observed Wolbachia-like bacteria in a primitive insect, Folsomia candida (Hexapoda, Collembola, Isotomidae). 16S rDNA analysis proved them to constitute a novel lineage, henceforth named group E, in the wolbachial phylogenetic tree. It shares 97.8% 16S rDNA homology with its nearest neighbors, groups A and B, which diverged from it more recently. We propose (i) a new taxon E for the Wolbachia strain in F. candida, (ii) that the single-described Wolbachia pipientis fall apart into at least three species: C, D and the large E-A-B complex. F. candida's group E Wolbachia rekindle the question about invasive capacities of free-living ancestral wolbachiae and horizontal transfer.
Animals↗
Stacker Modules Used in a High-Capacity Robotics System for High Throughput Screening Compound Replication.
High throughput screening is now established as a key component of the pharmaceutical lead identification process in many pharmaceutical companies. Over recent years, thanks to advances in assay technology, process automation, and logistics control, the throughput capacity of HTS groups has increased significantly. It is now entirely possible to screen corporate compound collections against an individual pharmacological target within a timescale of several weeks. Despite these improvements, many HTS groups find that their capacity is limited by the rate at which they can provide test compounds in a "screen-ready" format. This limitation is usually imposed by the capacity and productivity of the single-armed robotic systems utilized. We have recently constructed a robotic system aimed at overcoming this particular problem. This system uses purpose-built microplate stacker units that provide high-capacity microplate storage and, importantly, provide an easy and fast interface between the robotic system and the human operators. This paper describes this automation project and the benefits that have resulted from its deployment.
Journal Article↗
Voice, breathing, and the control of exercise intensity.
Explore the source record for details and available documents.
Adolescent↗
123I-5-I-R91150, a new single-photon emission tomography ligand for 5-HT2A receptors: influence of age and gender in healthy subjects.
5-HT2A receptors have been implicated in the pathophysiology of mood disorders and in the therapeutic effect of the so-called atypical antipsychotics. Recently, a new radioiodinated ligand with high affinity and selectivity for serotonin 5-HT2A receptors, 123iodinated 4-amino-N-1-[3-(4-fluorophenoxy)propyl]-4-methyl-4-piperidinyl] 5-iodo-2-methoxybenzamide (123I-5-I-R91150), has been developed and has been shown to be suitable for single-photon emission tomography (SPET) imaging. In this study the influence of age and gender on the ligand binding was investigated in normal volunteers. One hundred and fifty MBq of 123I-5-I-R91150 was administered to 26 normal volunteers (13 females and 13 males) with an age range of 23-60 years. SPET imaging was performed with a triple-headed gamma camera. For semi-quantitative analysis, ratios of ligand binding in different regions of interest to the binding in the cerebellum were calculated. Mean ratios of 1.7 were obtained. No gender difference was demonstrated. 5-HT2A binding was shown to decline with age. Over an age range of 40 years a reduction in ligand binding of 42% +/- 7% was found. These results are in agreement w in vitro and positron emission tomography findings of a decline in 5-HT2A receptor binding with age. The findings confirm the suitability of 123I-5-I-R91150 for SPET imaging of 5-HT2A receptors, and highlight the necessity for age-matched controls in clinical studies.
Adult↗
5-HT2A receptor blockade in patients with schizophrenia treated with risperidone or clozapine. A SPET study using the novel 5-HT2A ligand 123I-5-I-R-91150.
BACKGROUND: 5-HT2A receptor antagonism may be crucial to the action of atypical antipsychotics. Previous work has related 5-HT2A receptor blockade to clinical efficacy and protection from extrapyramidal side-effects. METHOD: We developed a SPET imaging protocol for assessing 5-HT2A receptor binding using the selective ligand 123I-5-I-R91150. Six healthy volunteers, five clozapine- and five risperidone-treated subjects with DSM-IV schizophrenia were studied. Multi-slice SPET was performed on each subject. RESULTS: Cortex:cerebellum ratios were significantly lower in both clozapine- and risperidone-treated subjects compared with the healthy volunteers in all cortical regions. There was no difference in occupancy between the two drug-treated groups. No correlation was found between the percentage change in the Global Assessment Scale (GAS) and 5-HT2A receptor binding indices in the drug-treated groups. CONCLUSIONS: Clozapine and risperidone potently block 5-HT2A receptors in vivo. The lack of relationship between receptor binding indices and change in GAS suggests that 5-HT2A receptor blockade may be unrelated to clinical improvement. Future studies will substantiate this finding by studying 5-HT2A receptor binding in large groups of patients treated with both typical and novel atypical antipsychotics.
Adult↗
Preclinical evaluation of [123I]R93274 as a SPECT radiotracer for imaging 5-HT2A receptors.
Studies in rodents have suggested that the radioiodinated 5-HT2A receptor antagonist [123I]R93274 (123-iodine-N-[(3-p-fluorophenyl-1-propyl)-4-methyl-4-piperidinyl]-4-ami no- 5-iodo-2-methoxybenzamide) (Kd = 0.1 nM) might be a promising single photon emission computerized tomography (SPECT) radiotracer to image 5-HT2A receptors in the living human brain. In this study, we characterized the brain uptake of [123I]R93274 in baboons. Highest brain uptake was observed in cortical areas, while lower uptake was observed in the striatum and the cerebellum. Injection of pharmacological doses of the 5-HT2A receptor antagonist ketanserin resulted in reduction of cortical and striatal radioactivities to the level observed in the cerebellum. Injection of the selective dopamine D2 receptor antagonist raclopride did not affect [123I]R93274 brain uptake. Quantification of 5-HT2A receptors was achieved by measuring the binding potential of 5-HT2A receptors for [123I]R93274 (the binding potential is the product of the density and affinity of available receptors). Regional binding potential values were derived with a three-compartmental kinetic analysis of the time-activity curves in the brain and plasma. Binding potential values of 93 +/- 34 ml/g, 71 +/- 35 ml/g and 31 +/- 11 ml/g were measured in the occipital, temporal and striatal regions, respectively. Similar values were derived using a noncompartmental graphical analysis. These values were in accordance with the in vitro regional distribution of 5-HT2A receptors in primate brain. In conclusion, [123I]R93274 allows visualization and quantification of 5-HT2A receptors in the baboon brain with SPECT.
Animals↗
Initial evaluation of 123I-5-I-R91150, a selective 5-HT2A ligand for single-photon emission tomography, in healthy human subjects.
The mapping of 5-HT2 receptors in the brain using functional imaging techniques has been limited by a relative lack of selective radioligands. Iodine-123 labelled 4-amino-N-[1-[3-(4-fluorophenoxy)propyl]-4-methyl-4-piperidinyl]-5-io do-2-methoxybenzamide (123I-5-I-R91150 or 123I-R93274) is a new ligand for single-photon emission tomography (SPET), with high affinity and selectivity for 5-HT2A receptors. This study reports on preliminary 123I-5-I-R91150 SPET, whole-body and blood distribution findings in five healthy human volunteers. Maximal brain uptake was approximately 2% of total body counts at 180 min post injection (p.i. ). Dynamic SPET sequences were acquired with the brain-dedicated, single-slice multi-detector system SME-810 over 200 min p.i. Early peak uptake (at 5 min p.i.) was seen in the cerebellum, a region free from 5HT2A receptors. In contrast, radioligand binding in the frontal cortex increased steadily over time, up to a peak at approximately 100-120 min p.i. Frontal cortex-cerebellum activity ratios reached values of 1.4, and remained stable from approximately 100 min p.i. onwards. Multi-slice SPET sequences showed a pattern of regional variation of binding compatible with the autoradiographic data on the distribution of 5-HT2A receptors in humans (cerebral cortex>striatum>cerebellum). These findings suggest that 123I-5-I-R91150 may be used for the imaging of 5-HT2A receptors in the living human brain with SPET.
Adult↗
Effect of absorption enhancers on ciliated epithelium: a novel in vivo toxicity screening method using rotifers.
Explore the source record for details and available documents.
2-Hydroxypropyl-beta-cyclodextrin↗
Overall and meal-specific macronutrient intake in Belgian primary school children.
In the fall of 1991, dietary intake of 1,321 primary school children aged 6-12 years was studied in 79 schools in an area called 'South Campine' in Flanders-the Dutch-speaking part of Belgium. Assessment of dietary intake was done using the '24-hour estimated food record method'. The energy distribution over the macronutrients showed no significant difference between boys and girls. On average 37.2% (SD 7.88%) of energy came from total fat and 15.4% (SD 3.70%) from saturated fatty acids; 49.0% (SD 7.87%) from total carbohydrates with 21.8% (SD 5.84%) from complex carbohydrates and 27.7% (SD 7.79%) from free sugars. Snacks accounted for on average 19.5% (SD 10.83%) of total energy intake; on average 55.7% (SD 21.22%) of the energy in these snacks was represented by free sugars. Lunch and dinner had very high fat contents (around 40% of energy). Already at this young age, the dietary pattern is deviating strongly from the recommended population nutrient goals.
Belgium↗
Serotonin: 5-HT2A receptor occupancy in vivo and response to the new antipsychotics olanzapine and sertindole.
Explore the source record for details and available documents.
Adult↗
Visualizing ocular melanoma using iodine-123-N-(2-diethylaminoethyl)4-iodobenzamide SPECT.
UNLABELLED: Radiolabeled benzamides have recently been introduced for the detection of melanoma. We evaluated the potential clinical applicability of 123I-N-(2-diethylaminoethyl) 4-iodobenzamide ([123I]IDAB) for SPECT imaging of ocular melanoma. METHODS: Fourteen patients were studied, 10 with or suspected of malignant ocular melanoma and four with ocular naevi. All patients underwent SPECT imaging of the head and whole-body scintigraphy 4-5 hr after injection of 170 MBq [123I]IDAB. RESULTS: A definite tracer hyperfixation was observed in the pathological eye in 9 of 10 (90%) patients with ocular melanoma. The pathological-to-normal eye ratio averaged 1.46 (range 1.07-2.86). The melanoma nature of the scintigraphic lesions was confirmed after enucleation in eight cases and by clinical evolution in two. A false-negative scan was reported in a patient with a small and hypochromic lesion. In patients with ocular naevi, no false-positive scintigrams were documented. CONCLUSION: Iodine-123-IDAB scintigraphy may contribute significantly to decide about enucleation in cases where some doubt persists with conventional techniques.
Benzamides↗
Synthesis of 2-[131I]iodophenyl-metyrapone using Cu(I)-assisted nucleophilic exchange labelling: study of the reaction conditions.
2-Bromophenyl-metyrapone has been synthesized as a precursor for Cu(I)-assisted labelling with radioiodine. A labelling yield of > 95% was obtained and the specific activity of the purified product was 120 GBq/mumol. The iodo for bromo exchange requires an excess of reducing agents to maintain the Cu(I) redox potential. The effects of the amount of reactants, temperature and time were studied. The labelling yield showed a direct dependence on the amount of precursor and Cu(+)-catalyst used for the reaction, and an increase with reaction time (optimal at 60 min) and temperature (optimal at 100 degrees C). Studies of the stability, lipophilicity and binding of 2-[131I]iodophenyl-metyrapone to serum protein indicated high in vitro stability, high lipophilicity (log P = 2.19) and a loose association with serum proteins.
Animals↗