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PubMed2002

Improvement of ciliate identification and quantification: a new protocol for fluorescence in situ hybridization (FISH) in combination with silver stain techniques.

A new protocol for taxon specific probe based fluorescent in situ hybridization was developed for the identification and quantification of ciliates in microbial communities. Various fixatives and experimental parameters were evaluated and optimized with respect to cell permeability and morphological preservation. Optimum results were adaption by obatined of a modified fixation method using Bouin's solution. Furthermore, conventional staining procedures such as different Protargol stain techniques and a silver nitrate impregnation method were modified and can now be applied in combination with fluorescence in situ hybridization. The new protocol allows a rapid and reliable identification as well as quantification of ciliates based upon classical morphological aspects and rRNA based phylogenetic relationships performed in one experiment. Furthermore, a set of specific probes targeting different regions of the 18S rRNA was designed for Glaucoma scintillans Ehrenberg, 1830 and tested by applying this new approach of combining in situ cell hybridization with conventional staining techniques.

Animals↗
PubMed1998

On the source-identification method.

The source identification method is a standard psychophysical procedure for studying the ability of listeners to localize the source of a sound. The method can be described in terms of a statistical model in which listeners' responses are determined by the width and bias of an internal distribution. This article presents a theoretical study of the method, particularly the relationships between the average experimental observables, rms error and variability, and parameters of the internal distribution. The theory is tested against source-identification experiments, both easy and difficult. Of particular interest is the experimental dependence of observable statistics on the number of sources in the stimulus array, compared with theoretical predictions. It is found that the model gives a good account of several systematic features seen in the experiments. The model leads to guidelines for the design and analysis of source-identification experiments.

Adult↗
PubMed2001

Effect of genotype on selected clinical features of Polish cystic fibrosis adults.

UNLABELLED: Cystic fibrosis (CF), the most common autosomal recessive disorder of Caucasians, is caused by the mutations in the gene encoding CFTR (Cystic Fibrosis Transmembrane Conductance Regulator) protein. Until now, approximately 1000 mutations of the CFTR gene have been described. The genotype-phenotype relationships in CF are still not completely understood. This study was undertaken in an attempt to characterise the distribution of CFTR mutations and their effect on selected clinical parameters in a group of Polish CF adults. A total number of 38 adult CF patients (mean age 21.6 +/- 6.8); 18 females & 20 males were enrolled in the study. The CFTR gene identification was conducted with the use of PCR & InnoLipa-CF set. The assessed clinical parameters included: age at diagnosis, age, lung function test, X-ray scored in Brasfield score, weight & height. We found that: (1) the genotypes of the studied population were unevenly distributed (65.8%- genotype deltaF508/M), (2) a high percentage of 3849+10kbC-->T was noted, (3) patients homozygous for the deltaF508 mutation were diagnosed significantly earlier and had a lower body mass index, (4) no differences were observed in the patients' length of life or the progression of lung disease. CONCLUSIONS: 1. In comparison to other populations, Polish adult CF patients display a relatively higher frequency of mild mutations. 2. Late diagnosis of CF in the studied group may be partially caused by a high percentage of CFTR mutations connected with the mild course of the disease that are difficult to identify. 3. Cystic fibrosis should be more commonly taken into consideration in the differential diagnosis in adult patients with milder symptoms.

Journal Article↗
PubMed1981

[Development of an automatic reporting system for radioimmunoassay test (author's transl)].

The system consists of a conventional RIA total system with a desk-top computer system, and a filing and reporting system of the RIA data with a flexible disk and a printer. Patient's identification is registered in the computer at the time of reception to RIA test. Their identifications are, reception date, name of RIA test, patient name, age, sex, doctor's name, name of clinical department, in- or out-patient, number of samples and it's sampling time, examination date of assay and comments included normal value. These data are recorded to a flexible disk sheet, and are combined with RIA examination data, when data process of radioimmunoassay finished. Result of the RIA test is automatically printed by the printer. Printed parameters are results of examination with standard deviation, and above described patient identifications. If necessary, time activity curves of the density are plotted too. Accurate and automatically reporting system has been applied to the routine RIA test.

Computers↗
PubMed1990

Effect of human seminal plasma on the lytic activity of natural killer cells and presumptive identification of participant macromolecules.

Using the lytic activity of natural killer (NK) cells as an in vitro parameter, the immunoregulatory properties of human seminal plasma (SePl) and participant macromolecules have been investigated. Significant (P less than 0.05) suppression of NK cell activity by SePl and chromatographically separable fractions was demonstrated in association with high and low molecular weight (Mr) macromolecules. SePl suppression was retained after heating to 56 degrees C for 30 min, and appeared to function at the level of the effector, rather than target cell. Physicochemical characterization of high and low Mr fractions provided presumptive identification of the participation of transglutaminase and prostaglandins as the principal molecules contributory to SePl immunosuppression.

Humans↗
PubMed1995

Association of enterohemolysin and non-fermentation of rhamnose and sucrose with Shiga-like toxin genes in Escherichia coli from calves.

Fecal Escherichia (E.) coli strains from calves were tested for simply detectable phenotypical features associated with Shiga-like toxin (SLT) genes. DNA hybridization with SLT-specific oligonucleotide gene probes (detection of genes for SLT-I and SLT-II) was the "gold standard" for the evaluation of Vero cell cytotoxicity, fermentation of several saccharides, beta-D-glucuronidase activity and production of alpha-hemolysin (alpha-Hly) or enterohemolysin (E-Hly). While SLTEC and non-SLTEC did not significantly differ in production of alpha-Hly, beta-D-glucuronidase activity and fermentation of D-sorbitol, production of E-Hly and non-fermentation of L-rhamnose (Rha) and D-sucrose (Suc) were associated with SLT genes. Sensitivity and specificity of the E-Hly+ phenotype were 53% and 88% for identification of calf SLTEC. When three markers were combined to form the parameter ["E-Hly+ or (Rha- and Suc-)"], sensitivity was higher (65%) and specificity was almost the same (85%). Production of enterohemolysin and inability to ferment rhamnose and sucrose were more often associated with the SLT-I gene than with SLT-II genes. Approximately 71% SLT-I+ E. coli were positive in the enterohemolysin assay. The test combination "E-Hly+ or (Rha- and Suc-)" and Suc-)" was most valuable for the presumptive identification of SLT-I+ E. coli (sensitivity 85%, specificity 83%). These data suggest that the phenotype "E-Hly+ or (Rha- and Suc-)" may be a helpful marker for the detection of SLT-I+ E. coli in SLTEC associated diarrhoea of calves.

Animals↗
PubMed1992

Quantitative magnetic resonance imaging parameters and their relationship to mammographic pattern.

BACKGROUND: Breast cancer exhibits wide international variation in incidence, which has led to the identification of several factors correlating with the risk of the disease. Magnetic resonance imaging (MRI) techniques can provide quantitative information about the biological and physical properties of tissue. PURPOSE: This work tested several magnetic resonance tissue parameters for their ability to distinguish quantitatively between breast tissues in subjects at substantially different risk for breast cancer as defined indirectly by their parenchymal pattern on mammograms. METHODS: Quantitative MRI parameters (relative water content, longitudinal relaxation time [T1], and transverse relaxation time [T2]) were measured for breast tissue using newly developed techniques in two groups of women with mammographic parenchymal appearance associated with high (Dy pattern [i.e., extensive nodular or diffuse density]; n = 12) or low (N1 pattern [i.e., breast containing mainly fat]; n = 11) risk of breast cancer. RESULTS: The two groups have significantly different average relative water content (P less than .0001) and average T1 (P less than .0001). Pixel histograms of T2 values show marked differences between the two groups which can be characterized with a fourth moment parameter. CONCLUSIONS: Quantitative MRI techniques exhibit good potential for assessing tissue characteristics in the breast that are associated with risk of breast cancer. IMPLICATIONS: Future work will address the direct correlation of MRI parameters with risk of breast cancer.

Adult↗
PubMed1981

Development and identification of a multicompartment model for the distribution of adriamycin in the rat.

The distribution kinetics of adriamycin in the rat were analyzed by using a multicompartment mathematical model. The set of a priori unknown model parameters, the drug rate constants, were estimated from 48 hr multicompartment drug distribution data by applying multivariate system identification techniques. Simultaneously, the information in all the measurements is exploited for the calculation of drug concentration time curves of each compartment of the model. No quantitative a priori information is required in the form of blood flow or membrane transport limitations. This approach requires only qualitative a priori biological information in the form of a mathematical model structure and successfully analyzes complex multidimensional pharmacokinetics. It results in a compact and realistic representation of physiologic drug transport processes.

Animals↗
PubMed2004

Coagulase-negative staphylococci: clinical, microbiological and molecular features to predict true bacteraemia.

Coagulase-negative staphylococci (CNS) are frequently isolated from blood cultures, where they may be only a contaminant or the cause of bacteraemia. Determining whether an isolate of CNS represents a true CNS bacteraemia is difficult, and there is no single criterion with sufficient specificity. The aim of this study was to assess those clinical, microbiological, pathogenic and genotypic features that characterize true CNS bacteraemia. Twenty patients having two or more blood cultures positive for CNS and 20 patients with only one positive blood culture were studied. Significant bacteraemia was defined according to clinical and laboratory criteria. Incubation time for blood cultures to become positive, macroscopic appearance of colonies, species determination, biotype, susceptibility to antimicrobials, PFGE pattern and adherence capacity were all studied. Clinical bacteraemia was present in 16/20 patients with two or more positive blood cultures and in 2/20 patients with only one positive blood culture. A significant difference was seen in the median time to positivity between the 18 clinical bacteraemias and 22 contaminations (23.6 versus 29.2 h; P = 0.04, Wilcoxon). There was also a significant difference between the two groups in the median absorbance of the slime test (1.36 versus 0.58; P = 0.005). All significant bacteraemias with two or more positive blood cultures had the same species identified, the same antimicrobial susceptibility pattern and the same PFGE pattern. In two patients with true bacteraemia with only one positive blood culture, the incubation time for the culture to turn positive was <24 h and the slime production absorbance was >2.5. The most useful parameters for the diagnosis of true CNS bacteraemia for patients with two positive blood cultures were incubation time until positive, species identification, antimicrobial susceptibility pattern, slime production and PFGE pattern. For patients with only one blood culture positive for CNS, the useful parameters for prediction of true bacteraemia were incubation time until positive and slime production, both of which are simple, low-cost tests.

Bacteremia↗
PubMedDate not supplied

Cluster analysis of nutritional and immunological indicators for identification of high risk surgical patients.

In spite of the many anthropometric, biohumoral, and immunologic parameters employed in the nutritional assessment of hospitalized patients, it is difficult in clinical practice to evaluate accurately the degree and type of malnutrition and to assess the prognostic significance of this determination. The purpose of this study is to evaluate nutritional status of surgical patients by means of cluster analysis in orderr to identify different nutritional patterns and to evaluate their clinical and prognostic significance. Nutritional assessment of 71 surgical patients was carried out at admission, and the sets of data were evaluated by means of cluster analysis. Four clusters with different nutritional patterns were identified. The incidence of clinical variables (type of disease, postoperative sepsis, palliative procedures, mortality at 6 months, etc.) in each cluster was determined in order to evaluate their clinical and prognostic significance. Cluster 1 showed minor variations of the indicators, including most of the controls presented the lowest incidence of sepsis, palliative procedures, and mortality at 6 months. It was then considered as a reference group representative of the normal nutritional condition at our institution. The other three clusters showed major variations of nutritional indicators and represent poorer risk clinical conditions. Sepsis, palliative procedures and mortality rate were significantly more frequent in these clusters (p less than 0.05, p less than 0.001, p less than 0.05). A different distribution in the clusters was recorded in gastrointestinal tract cancers and other neoplasms. Only the incidence of gastrointestinal tract cancers increases progressively in the clusters with poorer prognosis, suggesting that this type of neoplasia is more frequently associated with major changes of nutritional status.

Adult↗
PubMedDate not supplied

[A computer program for toxico-chemical analysis using gas chromatography].

A high probability of identification of substances containing nitrogen or phosphorus in their molecules is obtained by the original gas chromatographic (GC) system. It enables the reliability of positive identification in 98.43% of cases compared with the modern GC where for the chromatographic library spectrum of 200 substances the probability of identification of unknown substances is only 28.13%. GC system is based on the parallel configuration of the two capillary columns of different polarities connected to the one-column injector and the one nitrogen-phosphorus detector as well as the original computer program developed on the qualitative-logistic approach to interpretation of chromatographic parameters using only one reference substance. The computer program can perform positive logistic identification also in the case when the unknown substance is in the closest chromatographic vicinity, with quite different reference substances on both capillary columns.

Chromatography, Gas↗
PubMed2005

Impact of axillary nodal metastases on lymphatic mapping and sentinel lymph node identification rate in patients with early stage breast cancer.

PURPOSE: The aim of this study was to define the impact of the presence of axillary nodal metastases on lymphatic mapping and sentinel lymph node (SLN) identification rate in patients with early breast cancer. METHODS: Two hundred and forty-six lymphatic mapping procedures were performed with both labelled nanocolloid and blue dye, followed by SLN biopsy and/or complete axillary dissection. The following parameters were recorded: patient's age, tumour laterality and location, tumour size, tumour histology, tumour stage, tumour grade, lymphovascular invasion, radiotracer injection site (subdermal-peritumoural/peri-areolar), SLN visualisation at lymphoscintigraphy, SLN metastases (presence/absence, size) and other axillary metastases (presence/absence, number). Discriminant analysis was used to analyse the data. RESULTS: SLNs were identified by labelled nanocolloid alone in 94.7% of tumours, by blue dye alone in 93.5% and by the combined technique in 99.2%. Discriminant analysis showed the gamma probe SLN identification rate to be significantly limited by the presence of axillary nodal metastases. In particular, the size of SLN metastases and the number of other axillary metastases were the most important variables in reducing the gamma probe SLN identification rate (p = 0.004 and p = 0.002, respectively). On the other hand, high tumour grade was the only parameter limiting the blue dye SLN identification rate. CONCLUSION: The accuracy of lymphatic mapping with labelled nanocolloid is limited by the presence of axillary nodal metastases, and particularly by the degree of SLN tumoural invasion and the presence and number of other axillary nodal metastases. Neither of these elements seems to interfere with the blue dye identification rate. The combination of the two tracers maximises the SLN identification rate.

Adult↗
PubMed2001

Intra-Operative electromyographic monitoring of extra-ocular motor nerves (Nn. III, VI) in skull base surgery.

BACKGROUND: Extraocular motor nerves (Nn. III, IV, VI) are at risk of damage during skull base surgery. A new recording technique was employed in 18 patients suffering from various skull base tumours in order to extend intra-operative EMG monitoring to the extra-ocular muscles. METHODS: Selective intra-operative EMG recordings were obtained from extra-ocular muscles by placement of single-shafted bipolar needle electrodes under the guidance of B-mode ultrasound to visualise the needle tip within the target muscle in the orbital cavity. FINDINGS: Following bipolar electrical stimulation, the oculomotor nerve (N.III) was intra-operatively identified in 5 out of 7 cases, and the abducens nerve (N.VI) in 12 out of 18 cases. Postoperative (3-6 months) oculomotor nerve function remained unchanged in 5 and improved in 2 patients. No permanent deterioration was observed. Abducens nerve function deteriorated in two patients and improved in one case, but remained unchanged in 15 cases. No side effects occurred. There was neither any distinct relation of ocular motor nerve function to the kind and extent of SMA ("spontaneous muscle activity") patterns, nor could such relationship be detected with concern to neurophysiological parameters (latencies, amplitudes) of electrically evoked CMAP ("compound muscle action potentials"). INTERPRETATION: The EMG technique proposed proved to be mainly effective as a mapping tool for intra-operative localisation and identification of ocular motor nerves in skull base surgery. However, the predictive value of conventional neurophysiological parameters for clinical outcome, seems to be rather poor. Further studies on a larger number of patients are therefore required to develop new quantification techniques which enable an intra-operative prediction of ocular motor nerve deficits. Further efforts are also necessary to extend this technique to the trochlear nerve.

Abducens Nerve Injury↗
PubMed1983

Parameter interaction in the perception of French plosives.

This investigation takes as its point of departure observations on the production of French fortis versus lenis plosive consonants. In a series of perception tests the role of different parameters in the fortis versus lenis distinction found in production (e.g. duration of the pre-consonantal vowel, the consonantal closure, voicing during the closure and intensity of the consonantal release noise) was investigated. Apart from durational and intensity parameters, vowel quality differences (depending on the fortis versus lenis character of the following consonant) are also shown to play a part in phoneme identification. Furthermore it is shown that in obstruent clusters like /tp, dp/ versus /tg, dg/ not only do phonetic parameters like those mentioned above influence perception, but that also the phonemic identity of /p/ versus /g/ as fortis versus lenis contributes to the hearers' decision about the identity of the first consonant in the cluster. Phonetic as well as contextual factors are shown to interact in a complex manner. Implications of the results for speech perception theory are discussed.

France↗
PubMed1996

Evaluation of respirometric data: identification of features that preclude data fitting with existing kinetic expressions.

The use of respirometric for from the evaluation of intrinsic biodegradation kinetic parameters for single organic compounds is discussed. Emphasis is placed on the preliminary assessment of the data set to determine whether it is suitable for kinetic parameter estimation. Careful preliminary examination of the data avoids attempting parameter estimation with unacceptable data. Furthermore, the use of unbiased respirometric data helps ensure that the estimated parameters truly reflect the intrinsic kinetics for biodegradation of a single substrate by the culture tested. Both experimental and theoretical oxygen uptake curves are used to illustrate how various conditions can limit the utility of a given data set. The effect of substrate inhibition, dual or multiple substrate limited growth, inaccuracies in the initial conditions assumed for curve fitting, and the use of poorly acclimated cultures are discussed. Techniques are presented which allow identification of whether a data set is unsuitable and should not be used for parameter estimation. In addition, experimental procedures which can help avoid the collection of aberrant data are discussed.

Biodegradation, Environmental↗
PubMed2000

Risk analysis in esophageal surgery.

The postoperative mortality after esophagectomy still remains a major factor influencing the prognosis of esophageal cancer and largely depends on the patient's preoperative physiological status. A composite scoring system was developed to predict the risk of esophagectomy, based on quantitative assessment of preoperatively available physiological parameters. The scoring system was reviewed retrospectively on operated patients and evaluated prospectively in two subsequent patient groups. An initial retrospective multivariate analysis of 432 esophagectomy patients identified a compromised general status (p = 0.001) and poor cardiac (p < 0.001), hepatic (p < 0.05), and respiratory (p < 0.05) functions as independent predictors of a fatal postoperative course. Based on the relative risks associated with individual impaired organ functions--general status 3.6, cardiac function 2.8, hepatic function 2.1, pulmonary function 1.7--a composite risk score was established. A prospective study in 121 patients confirmed that this composite scoring system provides better identification of high-risk patients than does any of the individual parameters alone. Including this composite score into the process of patient selection and choice of procedure resulted in a decrease of postoperative mortality from 9.4% (52/553) to 1.2% (4/323) (p = 0.001). The risk of death after esophagectomy for esophageal cancer can be objectively assessed prior to surgery and quantified by a composite risk score. This score provides a useful tool in refining the criteria of patient selection for resection and choice of procedure, and markedly reduces postoperative mortality when applied prospectively.

Esophageal Neoplasms↗
PubMed2003

Influence of identification and preservation of pelvic autonomic nerves in rectal cancer surgery on bladder dysfunction after total mesorectal excision.

PURPOSE: Given the improvement in oncologic outcome after the introduction of total mesorectal excision for the treatment of rectal cancer, the objective of the present study was to determine the frequency of identification and preservation of the pelvic autonomic nerves and to identify a possible link between postoperative micturition disturbances and the extent of the radical resection. METHODS: Between March 1997 and December 2001, 150 patients with adenocarcinoma of the rectum (<or=16 cm from the anal verge) underwent surgery, with sphincter preservation in 112 cases (74.7 percent). Sixty-three patients (42 percent) were classified as American Society of Anesthesiologists Stage III and two (1.3 percent) as Stage IV. The number of cases with complete identification, partial identification, or nonidentification of the autonomic nerves (superior hypogastric plexus, hypogastric nerve, and inferior hypogastric plexus) was documented and correlated with micturition disturbances (need for a long-term urinary catheter). Urine volumes were measured by ultrasound before and after surgery. RESULTS: The pelvic autonomic nerves were identified completely in 108 patients (72 percent), partially in 16 (10.7 percent), and not at all in 26 (17.3 percent). After the initial phase of the study (n = 50 patients), complete identification was realized in 78 percent of cases. Multivariate analysis showed that of the predetermined parameters (learning curve for Group I vs. Groups II or III, gender, T stage, blood loss, curative surgery, and previous surgery), gender (P = 0.006), learning curve (P = 0.019), and depth of penetration of the rectal wall (T1/T2 vs. T3/T4; P = 0.028) exerted an independent influence on achievement of complete pelvic nerve identification. Sixteen patients (10.7 percent) were discharged from the hospital with a urinary catheter. Identification and preservation of the pelvic autonomic nerves was associated with low bladder dysfunction rates (4.5 vs. 38.5 percent; P < 0.001). In the evaluation of preoperative and postoperative bladder function, a urologic history and residual urine volume measurements by ultrasound were essential. The information obtained from urodynamic studies was of no relevance. CONCLUSIONS: Identification and preservation of the pelvic autonomic nerves was achieved in the majority of patients and led to the prevention of urinary dysfunction. Gender (P = 0.006), learning curve (P = 0.019), and T stage are independent parameters that influence outcome.

Adenocarcinoma↗
PubMed1989

Lexical effects on the phonetic categorization of speech: the role of acoustic structure.

This study examines the extent to which acoustic parameters contribute to lexical effects on the phonetic categorization of speech. Experiment 1 was designed to replicate previous findings. Two test continua were created varying in voice onset time. Results of both identification and reaction time (RT) range data showed an effect of lexical status at the phonetic boundary, but only in the slowest RT ranges, suggesting that lexical effects on phonetic categorization are postperceptual. Experiment 2 explored whether the lexical effect would emerge when the stimulus continua more nearly approximated the parameter values of natural speech. Both identification and RT range data indicated that the lexical effect disappeared. These results suggest that without attention to the acoustic structure of the stimuli, the role of top-down processing in phonetic categorization may be overemphasized.

Adult↗