Card Perseveration Task performance and post-task feeling states: relationship to drug use in adolescents

This study examined whether performance on the Card Perseveration Task (Card Task) and self-report of feeling state after the task are related to self-report of drug use. The evaluation was of 64 adolescents from an adolescent psychiatric outpatient clinic (40 males, aged 15.5 years, SD = 1.6; 24 females aged 16.9 years, SD = 1.5). Drug use histories were obtained using a substance dependence symptom checklist based on DSM-III-R. The Card Task was administered, and after completion, a Post-Task Self-Report (PTSR) was administered. A factor analysis with varimax rotation grouped the 28 items of the PTSR into Distress, Happy, Satisfied, and Wanting to Win subscales. Correlations of drug use with performance on the Card Task and the PTSR subscales were obtained. Cards Played on the Card Task were correlated with alcohol (cc = .31, p < or = .01); marijuana (cc = .35, p < or = .01) and polydrug (cc = .26, p < or = .05) dependence symptoms. Money Won on the Card Task was correlated negatively with nicotine (cc = -.26, p < or = .05) and marijuana (cc = -.27, p < or = .05) dependence symptoms. The PTSR Distress subscale correlated with nicotine (cc = .49, p < or = .001), alcohol (cc = .37, p < or = .01), marijuana (cc = .39, p < or = .01), and polydrug (cc = .49, p < or = .001) dependence symptoms. These findings provide evidence that both the Card Task and feeling states associated with task performance are related to self-reports of drug use.

Computerized classification of corpus cavernosum electromyogram signals by the use of discriminant analysis and artificial neural networks to support diagnosis of erectile dysfunction

Corpus cavernosum electromyogram (CC-EMG) provides diagnostic information on cavernous autonomic innervation and a measure of the degree to which the cavernous smooth muscle cells are intact. The complicated CC-EMG is evaluated and used in the diagnosis of patients suffering from erectile dysfunction. The evaluation procedure has been simplified by applying digital signal processing techniques. Since mathematically-based interpretations require quantitative data, spectral analysis was performed. The derived biosignals were analyzed by fast Fourier transform (FFT). Besides various other spectral parameters, specific frequency bands were determined in the power spectrum using factor analysis. The parameters were used for the computerized classification of normal and pathological CC-EMG data and the classification was performed using two independent methods: discriminant analysis (DA) and artificial neural networks (ANN). A medical expert analyzed a total of 200 CC-EMG recordings from patients with and without erectile dysfunction and separated these into normal (136) and pathological (64) cases. Although each independent method had already resulted in a relatively high number of correct classifications, the classification success rate could be slightly improved by using a combination of both classification methods. A total of 72.79% and 77.94% were successfully classified using DA and ANN, respectively. The combination of both methods increased the classification success to 80.15%. The results of this study enabled impartial evaluation of the CC-EMG signals for clinical diagnostic purposes of erectile dysfunction. This method provided an objective and easy way to analyze the CC-EMG. Furthermore, this results in patient diagnosis becoming an easier task for less experienced doctors, since little knowledge of the raw signal is needed.

High affinity regulation of cardiac Cl- and Ca2+ conductances by (13R)-spiroforskolin

The effects of a new forskolin derivative, (13R)-spiroforskolin, on the ventricular cAMP-activated chloride current (I(Cl(cAMP))) and the atrial L-type calcium current (I(Ca,L)) were measured by means of whole-cell recording from isolated guinea-pig cardiac myocytes at 30 degrees C and 20-22 degrees C, respectively. In contrast to forskolin, the derivative contains a tetrahydrofuran rather than a tetrahydropyran moiety. (13R)-spiroforskolin activated I(Cl(CAMP)) in 58% of the ventricular myocytes studied. The concentration required for the half maximal effect (EC50 value) amounted to 9.6x10(-11) M and was lower than the EC50 value for forskolin (2.4x10(-8) M). (13R)-spiroforskolin evoked a smaller maximal I(Cl(cAMP)) amplitude than forskolin. The rundown of the (13R)-spiroforskolin-activated I(Cl(cAMP)) was faster than that of the forskolin-induced current. Neither forskolin nor (13R)-spiroforskolin in maximally effective concentrations increased I(Cl(cAMP)) in cells containing high concentrations of cAMP. Furthermore, as an activator of atrial I(Ca,L) (13R)-spiroforskolin displayed a smaller activation and a lower EC50 value (5.8x10(-10) M) than forskolin (EC50 value: 3.7x10(-7) M). The effect of (13R)-spiroforskolin was observed in only 30% of the atrial cells studied. None of the drugs exerted a stimulatory effect in atrial cells containing a high [cAMP]. The washout of the drug effect was significantly faster in (13R)-spiroforskolin- than in forskolin-treated atrial myocytes. We conclude that (13R)-spiroforskolin as a forskolin derivative displays unique characteristics. It is a more potent but less efficacious activator of cardiac ionic conductances than the parent compound. The results suggest that (13R)-spiroforskolin, like forskolin, most probably exerts its effects via stimulation of the adenylyl cyclase.

[Electromyograms in erectile dysfunction and computer-assisted interpretation]

The electromyogram of the corpora cavernosa (CC-EMG) provides information on the autonomic innervation and/or smooth musculature. The interpretation of the CC-EMG, usually by evaluating signal patterns of higher activity, is time-consuming. To improve this situation, a computer-aided diagnosis employing a Microsoft Windows user interface was developed. The computer-aided interpretation is based on digital measurement data obtained using a 170.6 Hz sampling frequency and quantization of 10 V/12 bits of the signal. The first task of the program is to extract signal patterns of higher activity from stored data. To describe these patterns in mathematical terms, the features "relative time position", "relative reproducibility", "portion of normal phases", and "portion of whip phases" are calculated. Characteristic signal forms (normal and whip phases) are identified by means of syntactic pattern recognition. Using fuzzy logic, the features are used to effect pattern evaluation. To summarize the evaluated patterns, the variable "global normality" has been established, and linked to the "global synchronicity" at a second fuzzy logic level, to produce the final diagnosis. Finally, 30 records were evaluated independently by a team of experts and by the computer program. In relation to four established diagnostic classes, a correspondence of 70% was found. Furthermore, the accuracy achieved in each of the individual classes was better than 50%. Discrimination between normal and abnormal evaluation, which is of particular interest, reached 80%.

Computer-assisted evaluation of the smooth-muscle electromyogram of the corpora cavernosa by fast Fourier transformation

OBJECTIVE

The aim of our study was to investigate analogous and digital recording of corpus cavernosum EMGs (CC-EMGs) in normal men according to criteria that were recently agreed upon in an international consensus workshop.

METHODS

CC-EMGs were analogously and digitally registered from 37 normal subjects. Power spectra in the frequency domain were determined via fast Fourier transformation (FFT).

RESULTS

Thirty-one of men showed identical or at least very similar electrical activity patterns in the analogous and digital registration. Needle penetration artifacts (investigated in 18 subjects) were found in 17/18 CC-EMGs during the first 20 min. Power spectra show a maximum of power at a frequency of 0.3 Hz with more than 90% of the power located between 0 and 5 Hz.

CONCLUSIONS

Registration of CC-EMGs in normal men resulted in interindividually reproducible recordings. Age hardly affected CC-EMGs. Computer-assisted evaluation by FFT after elimination of artifacts was feasible. Thus, interpretation of the CC-EMG signals by a computer-aided expert system seems to be promising for clinical routine, in particular with respect to an increase in objectivity and a decrease in time needed for interpretation.

On the correlation of mechanical and optical properties of cataractous eye lens nuclei

It is investigated whether mechanical properties of human cataractous eye lens nuclei can be assessed by their optical ones. This question is of importance as the success of phacoemulsification surgery among other criteria depends on the mechanical properties of the lens nucleus. The mechanical and optical properties of senile cataractous human eye lens nuclei were tested in vitro after extracapsular cataract extraction. A new measurement system was developed to determine their mechanical response. Hereby, a force is applied to the specimen and the resultant displacement is measured or vice versa. Stiffness and ultimate strength of the material are determined. Optical transmission is detected in dependence of light wavelength by a spectrophotometer. In addition the nuclear colour is determined. The correlation of mechanical stiffness and strength via optical transmission at 550 nm and nuclear colour is analyzed. Human eye lens nuclei show a viscoelastic mechanical behaviour. Measurement of stiffness is reproducible after 5-6 loading cycles when a steady-state is reached. Mechanical and optical properties correlate weakly but significantly. Stiffness and strength increase with increasing nuclear coloration. Alterations of mechanical and optical properties are caused by the same structural changes of the molecular components of the ageing lens. Especially lens crystallines are responsible for this process. Thus, it is concluded that optical properties can be useful to assess the mechanical response of cataractous eye lens nuclei.

Computer-assisted interpretation of electromyograms of corpora cavernosa using fuzzy logic

An electromyogram of the corpora cavernosa (CC-EMG) imparts information on the autonomic cavernous innervation and/or the cavernous smooth muscles. The CC-EMG is interpreted mainly by evaluation of signal patterns of higher activity. The time required for interpretation is reduced by the implementation of a computer-assisted diagnosis program with a Microsoft Windows user interface. The program offers four levels of diagnosis: on the first level, recordings can be edited; on the second and third levels, signal patterns can be searched or evaluated; and on the last level the final diagnosis is provided. The computer-assisted interpretation is based on digital measurement data. These data have been obtained through a 170.6-Hz sampling frequency and a quantization of 10 V/12 Bit of the amplified signal. The first task of this diagnosis program is to discover and extract signal patterns of higher activity from data stored on the hard disk of a personal computer (PC). For a mathematic description of these patterns the following features were defined: relative time position, relative reproducibility, part of normal phases, and part of whip phases. Syntactic pattern recognition was introduced to identify the characteristic signal forms. An evaluation of the patterns could be derived from these features using fuzzy logic. For a summary of the evaluated patterns the variable global normality was established. The global normality forms an important evaluation basis along with the global synchronism, which represents an investigator's first impression of a recording. The final diagnosis is completed using fuzzy logic. The program was tested by comparison of expert and computer diagnoses. A total of 30 records were independently evaluated by an expert team and the computer program. With reference to the four classified levels of diagnosis a correspondence of 70% could be found. Furthermore, the rate in each of the classified levels was higher than 50%. The discrimination between normal and abnormal evaluation was 80% for clinical routine. Our results show that a computer-assisted interpretation of the CC-EMG can be achieved using mathematically based software. Within the last 7 months this computer-assisted CC-EMG program proved to be of great help in routine diagnosis. Furthermore, it demonstrated results comparable with a blinded-expert interpretation. This approach should bring about dramatic improvements in the diagnosis of erectile dysfunction.

Application of factor analysis for the determination of specific frequency bands in corpus cavernosum EMG power density spectra

Corpus cavernosum electromyogram (CC-EMG) recording provides diagnostic information on cavernous autonomic innervation and the intact state of cavernous smooth muscle cells. Evaluation of these signals is time consuming and complex. Therefore, we attempted to facilitate their interpretation and to increase their objectivity by using computer-based digital signal processing. Spectral parameters were used as a starting point for this analysis, which were calculated from the Fourier-transformed time domain CC-EMGs. Factor analysis was applied to determine specific frequency bands in the CC-EMG power density. Two hundred power spectra, taken from normal subjects (n = 66) and from patients suffering from erectile dysfunction (n = 134), constituted the basic data. As a result of applying factor analysis, four specific frequency bands were depicted: 0.0-0.3, 0.3-3.5, 3.5-6.0 and 6.0-10.0 Hz. The results of this study form the basis for further mathematical evaluation and calculation of the CC-EMG for clinical and diagnostic purposes.

Mechanical testing of isolated senile human eye lens nuclei

Phacoemulsification is a cataract surgery technique during which the eye lens nucleus is carefully dissected by an oscillating hollow needle simultaneously serving as a suction line for lens fragments. As the success of this procedure depends greatly on the mechanical properties of the nucleus, the basic mechanical properties of extracted senile human eye lens nuclei were studied. For this purpose a novel measuring system had to be developed enabling the study of the biomaterial's responses to any chosen excitation function. Either force- or displacement-controlled testing signals can be selected serving as a one-dimensional input. The resultant quantity can be recorded in the time or frequency domain. An almost linear viscoelastic behavior of lens nuclei is observed. Typical phenomena such as hysteresis, creep, relaxation, and a frequency-dependent compliance are evaluated. The ultimate strength of the specimen is studied by penetration tests. Finally the possible correlation between mechanical and optical parameters of lens nuclei is discussed. If correlated, a surgeon could use this information when deciding whether an extracapsular extraction or a phacoemulsification should be the preferred approach.

Identification of fungi growing within soft contact lenses: a report from the neotropics

We isolated and identified 17 fungi within the matrix of 17 soft contact lenses (SCLs). This work was done in a neotropical location where climatic conditions favor year-round fungal growth. The fungi identified belong to eight genera, four of which have not previously been found contaminating the surface or the matrix of SCLs.

Neuroparacoccidioidomycosis: case reports and review

Cerebral and cerebellar masses occurred in patients with paracoccidioidomycosis. Correct diagnosis was delayed due to overlooking the abnormal lung roentgenograms and the history of previous disease in a different localization. The fungus was identified through biopsy and direct examination of the samples. In two patients necropsy confirmed the diagnosis. None of the patients responded to amphotericin B or cotrimoxazole. A 10 year English and Latin American literature review on neuroparacoccidioidomycosis was performed through a MEDLINE and LILACS (Latin American Literature Search System) data base systems.

Ecological control of hospital engineering operations

Environmental protection must be accomplishable in a hospital. Thus the goals have to be set in such a way that they are achievable. The track towards a positive environmental balance should be passable, ie environmental protection has to be on the people's mind and not on some single persons'. Environmental protection in the hospital starts in the purchasing department. If hospitals show an environmentally conscious demand, the industry will react with the supply of non-polluting products in order to not lose this market sector. Medical and the remaining hospital services may contribute to the protection of the environment by avoiding, reducing, and recycling waste. The responsibility for environmentally protective measures, such as noise reduction, sewage- and waste treatment, and avoidance of air pollution lies with hospital engineering. Operations (measuring, controlling) and maintenance (inspecting, servicing, overhauling) have to be available, safe, and economical. Thus the ecological demands for operations control are identically satisfied. The only task of the administration remaining is to support environmental consciousness and practice of environmental protection, to distribute attained knowledge and to survey the developments. Good environmental practice has to quantify environmental protection in the hospital.