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PubMedDate not supplied

[Morphological structure of the domestic cat (Felis catus) hair].

Felis catus hairs from different parts of its body were examined. Examination of some hair parameters allow the author to propose the following strategy of cat identification: 1) hair length divides cats into long- and short-haired; 2) identification of the species: a) long-haired--by medullary substance/hair thickness ratio; b) short-haired--by the presence or absence of osteal and transition hairs, by thickness of the osteal hairs. This scheme allows identification of the species of an individual cat.

Animals↗
PubMed2004

Procalcitonin serum levels in perinatal bacterial and fungal infection of preterm infants.

AIM: To determine reference values for procalcitonin (PCT) and C-reactive protein (CRP) for gestational age and to use these parameters as diagnostic markers of perinatal bacterial and fungal infection. METHODS: PCT and CRP serum levels were measured in a case-control study in a group of 35 low birthweight infants (< 34 wk of gestation). 27 babies (77%) had clinical signs of infection confirmed by positive blood cultures and were compared to 8 (23%) uninfected matched patients. Seventeen (63%) of them had bacterial infection and 10 (37%) had fungal infection (Candida). Serum PCT (Brahms Diagnostika) and CRP (Immunoassay Vitros 950) were measured serially at 3, 7 and 10d of life. RESULTS: At any time, PCT and CRP levels were significantly higher in neonates with perinatal infection (p < 0.05) (> 0.7 ng ml(-1) and > 1 mg dl(-1) respectively). PCT showed a more rapid response to infection (9.3 +/- 1.5 ng ml(-1)). especially to bacterial infection (10.8 +/- 1.4 ng ml(-1)), than CRP (1.5 +/- 0.5 mg dl(-1)) (sensitivity 99% vs 88%). Lower sensitivity was noted for both parameters. PCT and CRP, to follow babies with fungal infection (6.7 +/- 0.8 ng ml(-1) and 0.9 +/- 0.7 mg dl(-1), respectively) (sensitivity 77% vs 58%). CONCLUSION: This study gives PCT reference values in preterm babies with perinatal infection. In these babies, PCT seems to be more sensitive than CRP as a diagnostic marker of infection. Both parameters can be used alone or in combination for a better identification and follow-up of bacterial and fungal infection during the perinatal period.

Bacterial Infections↗
PubMedDate not supplied

[The efficacy of different oral dosage forms of furazolidone for E. coli infections in carrier pigeons].

The clinical efficiacy of furazolidon for treatment of E. coli-induced gastro-intestinal infections in racing pigeons was investigated. 36 adult pigeons were treated with 2 different oral modes of application (capsule/drinking water) with a daily therapeutic dosage of 12.5 mg furazolidon/pigeon. The pigeons used for this study (Columba livia f. domestica) originated from conventional breeders and were housed in 3 different groups (control-, capsule- and powder-group) in different stables. After infection with an E. coli-strain (O150:H8) that proved to be pathogenic for pigeons, the animals developed clinical signs of disease within 2 days. After onset of disease the treatment with furazolidon for 5 days started. This phase was followed by an adspectory phase for 6 days. The negative identification of the E. coli O150:H8 was determined as main parameter for the clinical efficiacy of the treatment with furazolidon. This parameter showed a highly significant (p = 0.0001) difference between both groups treated with furazolidon and the control group. In both groups treated with furazolidon the E. coli strain could not be isolated after the end of the treatment. An improvement of clinical signs was seen 24 hours after treatment via capsule and 48 hours after treatment via drinking water formulation. The time difference might be caused by the high concentration of furazolidon in the capsules due to the single daily application. Considering the inaccurate dosing via drinking water that results from the varying drinking water intake in pigeons, the application by capsule should be prefered. Both furazolidon preparations proved to be effective in treating gastro-intestinal E. coli-infections in racing pigeons in a dosage of 12.5 mg/pigeon for 5 days, however, best results were obtained by application via capsule.

Administration, Oral↗
PubMed1991

[Coronary venous blood flow in patients with acute myocardial infarction].

In 94 patients with large myocardial infarction, their coronary venous blood flow was studied in the acute period of the disease by continuous coronary sinus thermodilution. No relationship was established between the coronary venous blood flow and the duration of coronary heart disease. The patients with anterior myocardial infarction had a significantly less blood flow in the vena cordis magna than those with posterolateral infarction. No correlation was found between the blood flow and precordial mapping parameters. Thus, continuous coronary sinus thermodilution cannot be used for indirect identification of the site of myocardial infarction and for prediction of its progression severity.

Adult↗
PubMedDate not supplied

[Soft-tissue sarcomas of the extremities. Their assessment with magnetic resonance].

MR imaging was performed on 38 patients with suspected malignant soft-tissue tumors of the extremities. MR diagnostic accuracy was compared with that of other methods. All patients underwent surgical control. In 7 cases MR imaging was employed to demonstrate the tumor response to antiblastic local perfusion. Lesion identification, extension, compartmental evaluation, bone and vascular involvement were the diagnostic parameters considered. In all cases MR imaging detected the lesion, correctly showing the intracompartmental (16 patients) or extracompartmental (22 patients) extension. In 2 out of 6 cases MR imaging did not demonstrate bone invasion, and in 1 case vascular involvement could not be assessed. MR diagnostic accuracy was superior to that of other techniques. Nonetheless, a diagnostic protocol was proposed for the local staging of malignant soft-tissue tumors of the extremities where some diagnostic limitations of MR imaging are taken into account--i.e., inconsistent evaluation of bone and vascular involvement. Plain X-rays and US are the imaging modalities of choice, whereas MR imaging is to be a second-choice diagnostic technique before biopsy. Thus, MR imaging replaces CT, while angiography is to be used in selected cases, where MR imaging is not diagnostic due to vascular involvement.

Adolescent↗
PubMed1982

[Sinus node function test--diagnostic value and methodologic limits].

By means of atrial stimulation methods for the establishment of the sinus node recovery time and for the indirect calculation of the so-called sinuatrial conduction time under certain methodical conditions disturbances of the sinus node automatism and of the sinuatrial conduction may be differentiated and moreover latent dysfunctions of the sinus node may be unmasked. Methodical problems in the recognition of the sinus node recovery time by higher-frequent atrial stimulation and the calculation of the sinuatrial conduction time by programmed atrial single or double manifold stimulation result above all on that account, since the various factors which determine the reaction of the sinus node in atrial stimulation are not to be surveyed in the individual case. Since there are no obligatory and reliable criteria for the judgment of the function of the sinus node a statement on sensitivity and specificity of the diagnostic stimulation methods is scarcely possible. With regard to a therapeutic decision aid a higher-frequent stimulation for the determination of the sinus node recovery time is of greater importance than the calculation of the sinuatrial conduction time. For the identification of a disturbed function of the sinus node the two parameters make a diagnostic contribution of approximately the same value.

Cardiac Pacing, Artificial↗
PubMed1982

Characterization of a control switch in chymotrypsin.

Kinetic and thermodynamic parameters of the conformational change accompanying the binding to chymotrypsin of a substance carrying substrate specificity have been determined by a chemical relaxation method. An analysis of the concentration dependence of the two relaxation times and the associated amplitudes permitted the evaluation of rat constants, reaction enthalpies, and entropies of the individual steps. The pH and temperature dependencies of these parameters allowed, together with the known topography of the molecule, the identification of the ionizing groups involved in the regulation of the two steps. The combined evidence was used to compose a detailed mechanism for the function of the conformational change. The hypothesis is proposed that the side chain of ASp-194 is acting as the tongue of a switch which is moving between the positively charged His-57 side chain (catalytically inactive state) and the positively charged alpha-amino group of Ile-16 (active state), thus activating or deactivating the catalytic site. This control switch is very sensitive to changes in pH and temperature.

Binding Sites↗
PubMed1995

An immunological outcome predictive score for head and neck carcinoma patients.

AIM: To address the increasing demand for individualization of tumor therapy, a panel of immunological parameters was evaluated as potential early prognosticators for the outcome of treatment. PATIENTS AND METHODS: Thirty-one patients with advanced squamous cell carcinomas of the head and neck were treated either with a 2-course radiation treatment (60 to 70 Gy total dose) in combination with and subsequent to the administration of mitomycin C and 5-fluorouracil (radiochemotherapy) or with radiotherapy (2 patients) only. In 8 patients radio(chemo)therapy was preceded by surgical removal of the tumor. Before, during and after therapy, patients were immunophenotyped (in absolute numbers) and the respiratory burst function of granulocytes (polymorphonuclear [PMN] cells) was evaluated flow cytometrically. RESULTS: Before treatment a reduction of T and B lymphocytes to 64% to 81% of the means of 101 controls (healthy volunteers and hematologic normal patients) was observed, absolute PMN counts were increased by 31%, whereas monocytes and natural killer cells were not influenced. The helper (TH)/suppressor-cytotoxic (Ts/c) T cell ratio was significantly elevated. The respiratory burst reaction of the majority (74%) of patients was normal. During therapy all lymphocyte populations declined further as did the PMN counts. Natural killer cells were not significantly influenced while absolute monocytes increased significantly beyond normal levels after initial depletions during each course of treatment. The helper/suppressor ratio was reduced to normal levels. Overall, treatment resulted in systemic effects at the level of leukocyte subpopulations and appeared to cause a shift of immunocompetence to a predominantly monocytic system. The deficiency in the humoral immune system could be correlated with the short survival time of most patients. Based on early effects of the treatment (after 10 Gy), an immunological outcome predictive score could be defined. A simple mathematical combination of the changes of B and Ts/c cells (after 10 Gy vs. 0 Gy) together with the respiratory burst reaction of PMN prior to treatment allowed retrospectively to classify correctly 90% (17/19) of patients as survivors (> 120 weeks) or early deaths (< 96 weeks; p < 0.01). CONCLUSION: Single individual immunological data were not able to function as prognosticators for longer survival after therapy, but a combination of 3 parameters measured early during radio(chemo)therapy seems to allow the identification of "sensitive" patients. In how far the tumor disease per se and/or the immunological "sensitivity" are causes of death in these patients requires further clarification.

Adult↗
PubMed1994

Biochemical and cellular characterization of cardiac valve tissue after cryopreservation or antibiotic preservation.

It has been reported that aortic homografts that have been cryopreserved before transplantation remain viable longer as an allograft than tissue stored at 4 degrees C in an antibiotic solution. In the present study, we tested the hypothesis that storage of cardiac valve tissue by cryopreservation or by antibiotic preservation may alter the metabolic status of the tissue. Initially, we collected aortic valves composed of cardiac tissue, aortic root, and valvular tissue from cadaver donors. These specimens were divided into three equal portions, and one portion was analyzed before storage while the other two parts were stored for 3 weeks at either 4 degrees C in an antibiotic solution or at -196 degrees C in liquid nitrogen. All specimens were examined with regard to the following parameters: tissue structure, tissue viability, cell proliferative capacity, metabolic function, and identification of cell-specific antigens. We found no significant alterations in the structure of any of the three tissue components after antibiotic preservation or cryopreservation; however, cell viability and cell number were decreased in all three groups. All tissue samples grew in culture before storage. When we compared activities of the following organellar marker enzymes--lysosomal acid lipase, plasma membrane 5' nucleotidase, mitochondrial cytochrome oxidase, and microsomal neutral alpha-glucosidase--we observed no major differences between tissues stored by either technique. In addition, we observed no loss of enzymic activity as a result of storage. Finally, when cell lines isolated from each tissue specimen were incubated with monoclonal antibodies against cell-specific antigens in an immunoperoxidase assay, all the cell cultures proved to be endothelial cells. These results suggest that although cardiac valve tissue stored by cryopreservation or by antibiotic preservation retained its normal structure and metabolic capabilities, both storage techniques produced significant decreases in cell numbers and viability. However, only endothelial cells from tissue stored by cryopreservation retained the capacity to proliferate in vitro. These findings have important implications for the function of aortic homografts transplanted after storage.

5'-Nucleotidase↗
PubMed1993

[Cardiodynamics and myocardial contractile reserve in patients with hypertrophic cardiomyopathy].

Cardiodynamics and myocardial contractile reserve were studied in 60 patients with hypertrophic cardiomyopathy by using radionuclide ventriculography at rest and during graded exercise test. All findings that characterize cardiodynamics (normal or higher overall ejection fraction and stroke volume or lower end-systolic volume, higher maximum ejection rate) show the contractility of the left ventricle in patients with hypertrophic cardiomyopathy which can be regarded to be more severe. During graded exercise test, in patients with hypertrophic cardiomyopathy three types of reactions were identified: (1) positive inotropic effect; (2) negative inotropic effect; (3) intermediate (deviation of major cardiodynamic parameters was no more than 20-25% of the baseline levels). Identification of the above types allows one to assess the presence and conditions of myocardial contractile reserve implementation in these patients and to objectivize the choice of corrective drugs.

Adolescent↗
PubMed1996

[Gene transfer in human hematopoietic stem cells isolated from peripheral blood].

To insert a new genetic information by gene transfer into haemopoietic stem cells would result in expression of the transgene in progenitors and progeny of cell blood lineages. If successfull, such an approach would open interesting prospectives in the field of experimental research and in the possibility to treat genetic defects affecting blood lineages such as immune deficiencies (ADA, SCID, AIDS) or enzymes defects. Moreover progenitors could be engineered to become more resistant to chemotherapy or oncogenic process. Many parameters and technical problems are still involved in this issue, including identification, isolation and selection of the most primitive progenitors, and search for the most efficient vectors to insert new genes into the target cells. So far retroviral vectors have been shown to be the most effective but search for better vectors are still underway. Peripheral blood stem cells isolated from patients stimulated by cytokines and/or chemotherapy appear interesting target cells for genetic manipulations aimed to correct an acquired or genetic defect.

Gene Transfer Techniques↗
PubMed1997

[Target population for hypertensive therapy].

The efficacy of treatment may be demonstrated globally but, in some patients, treatment can be either inappropriate or harmful because of undesirable secondary effects. Ideally, treatment should be limited to patients who respond, but this is impossible with the published data from clinical trials. This could become possible by creating a data base containing all published results and carrying out meta analyses on individual parameters. Using the most powerful methods of analysis this could allow identification of patients responding to treatment by taking into account not only the benefits but also the risks of a given treatment (the principle is to identify and estimate factors--demographical, sociological, generic, which interfere with the size of the effect). In order to identify responders to antihypertensive treatment, a meta analysis of individual data was started, the INDANA project. With a common data base of all the preventive trials of antihypertensive therapy, this study should contribute to improved identification of responders and therefore to individualization of treatment of hypertension.

Antihypertensive Agents↗
PubMed1998

[Tumor suppressors--genes and proteins].

Cancer is generally understood to be a genetic disease in the sense that somatic mutations are the cause of tumour initiation and development. Our knowledge of cancer-associated genes and gene products has evolved mainly over the past 20 years. The identification and characterization of tumour suppressor genes (TSGs) as normal growth-inhibiting or apoptosis-inducing genes have helped us to understand how mutations are tumorigenic. Various TSG encoding membrane-, cytosol-, or nuclear proteins have been identified. Tumor suppressor genes are often functionally inactive in cancer cells because of mutations of both parental gene copies. Many TSGs are associated with hereditary cancer diseases or syndromes caused by the existence of one mutant allele in the germ-line. Individuals who carry only one functional gene copy, are therefore at great risk of developing cancer. Several TSGs, such as TP53, RB1 and CDKN2A, encode proteins that are significant to the cell cycle. TP53 is the most frequently mutated gene in human cancer, showing changes in more than 50% of all solid tumours. Both DNA repair and apoptosis are stimulated by p53-induced transcription of genes involved in the two processes. The characterization of TSGs and their gene products has led to the identification of a number of new diagnostic and prognostic molecular genetic parameters in oncology. Furthermore, some TSGs are potentially among the most promising and important targets for gene therapy in cancer and other hyperproliferative diseases.

Animals↗
PubMed1998

[Influence of genetic variation at apoprotein A-1 gene promoter region on plasma lipid levels in heart transplantation patients].

BACKGROUND: To study if the presence of the G/A polymorphism at the apo A-I gene promoter region could determine the lipid profile in patients with hyperlipidemia after heart transplantation, or if it is related with the type of heart disease that determined the transplantation. PATIENTS AND METHODS: This study included 31 patients with hyperlipidemia after heart transplantation. Anthropometric parameters, basic analytic and lipid study were measured in these subjects. Identification of the G/A mutation in the promoter region of the apo A-I gene was performed. RESULTS: 22 patients had the G/G genotype and 9 the G/A. 14 were transplanted by coronary heart disease and 17 by non ischemic heart disease. Patients with the A allele had higher cHDL (63 [SD 15] vs 53 [10]; p = 0.034) and apo A-I plasma levels (156 [34] vs 132 [24]; p = 0.040) than G/G subjects. The A allele was present in the 18% of the patients transplanted by ischemic heart disease and in the 43% of the transplanted by another etiology (p = 0.073). CONCLUSIONS: The presence of the G/A genotype in the promoter region of the apo A-I gene determines higher plasma levels of cHDL in patients with hyperlipidemia after heart transplantation.

Adult↗
PubMed1989

The correlation of mononuclear cell phenotype in endomyocardial biopsies with clinical history and cardiac dysfunction.

Endomyocardial biopsy specimens from 96 patients with unexplained congestive heart failure or dysrhythmia were evaluated by standard histologic techniques and by direct immunofluorescence and immunoperoxidase cell marker analysis for mononuclear cell infiltration. Control specimens derived from normal autopsy hearts (n = 8) and autopsy hearts with severe coronary artery disease (n = 9) were analyzed in a similar fashion. The results were correlated with functional data obtained from cardiac catheterizations as well as the clinical history. The objectives of the study were to assess the sensitivity and specificity of immunoperoxidase identification of lymphocytes for the diagnosis of myocarditis and to correlate clinical parameters such as degree of cardiac dysfunction and symptom duration with the extent of inflammatory changes. No control biopsies (neither normal nor ischemic) had a T-cell concentration of one or more cells per high-power field (HPF:200X), whereas 32% of the study cases had more than one T-cell per HPF. Heavy T-cell infiltration (greater than or equal to 3 per HPF) was present in 7% of the study cases and occurred most commonly when the symptoms were of recent onset. The results demonstrate that lymphocytes are not present (less than 1 per HPF) in normal myocardium, in viable myocardium from hearts with generalized coronary artery disease, and in most endomyocardial biopsies (68%) from patients with unexplained heart failure or dysrhythmia. Thus, lymphocyte infiltration is not a nonspecific response to cardiac dysfunction. Immunoperoxidase identification of lymphocytes provides a quantitative assessment of inflammatory cell infiltration that is useful in the detection of myocarditis.

Adolescent↗
PubMed1997

[Stress myocardial gammatomography in the diagnosis of multivessel coronary disease].

OBJECTIVE: The aim of the study was to evaluate the diagnostic yield of 99m-Technetium-methoxy-isobutyl-isonitrile (MIBI) SPET for identification of individual coronary artery disease and in the prediction of multivessel involvement. METHODS: Stress/rest myocardial SPET and coronary arteriography were evaluated in 231 consecutive patients (age 58 +/- 10 years, 26% women) without prior myocardial infarction. 149 patients had coronary narrowing > 50%: 104 with multivessel disease and 45 with one vessel disease. Tomographic stress defect score was obtained by semiquantitative analysis (maximal score 65). Univariate and multivariate analysis was performed to identify discriminant parameters between one vessel and multivessel patients. RESULTS: The sensitivity and specificity for the identification of individual artery disease was 74% and 85% for left anterior descending artery, 79% and 85% for right coronary and 45% and 96% for circumflex artery. In the prediction of multivessel involvement the sensitivity was 65%, specificity 87%, positive predictive value 81% and negative predictive value 76%. In the bivariate analysis, four parameters differed significantly between one vessel and multivessel disease patients: ST downslope > 1 mm (p = 0.01), ST downslope/heart rate corrected (p = 0.005), reversible defects in two or more regions (p = 0.009) and SPET score (p = 0.002). In the multivariate analysis the probability of multivessel disease was 90% when ST depression > 1 mm and SPET score > 20 were associated and the probability was lowered to 16% when these criteria were not present. CONCLUSION: Myocardial SPET with MIBI offers an accurate localization of individual coronary artery disease, mainly in left anterior descending artery and right coronary artery lesions. Combined evaluation of ST depression and extension of myocardial stress defects improved prediction of multivessel involvement.

Coronary Disease↗
PubMed2002

Impact of visual function on computer task accuracy and reaction time in a cohort of patients with age-related macular degeneration.

PURPOSE: To investigate the impact of visual function parameters on computer task performance in patients with age-related macular degeneration (AMD). DESIGN: Interventional case series. METHODS: Eighteen patients with visual impairment due to age-related macular degeneration underwent evaluation of visual acuity using the Early Treatment Diabetic Retinopathy Study protocol, contrast sensitivity using a Pelli-Robson chart, binocular simultaneous visual field using the Esterman program on an automated perimeter, and color vision using Farnsworth D-15. Each subject then completed 125 computer icon identification tasks. Relationships between computer task performance (accuracy and speed) and visual function parameters (visual acuity, contrast sensitivity, visual field, and color vision) were analyzed. RESULTS: Visual acuity and contrast sensitivity in the better eye, weighted average contrast sensitivity, and color vision defects are significantly associated with computer task accuracy. Visual acuity in the better eye, weighted average visual acuity, and color vision defects are significantly associated with performance speed. Visual function parameters and clinical features significantly associated with computer task accuracy in a multiple regression model include weighted average contrast sensitivity (P = 0.001), protan color vision defect (P = 0.002), cataract severity in the better-seeing eye (P = 0.036), and geographic atrophy outside the central macula (P = 0.046). Visual function parameters and clinical features significantly associated with computer task speed in a multiple regression model include color vision defects (deutan, P < 0.001; protan, P < 0.001) and gender (P = 0.05). CONCLUSIONS: Among this cohort of patients with AMD, visual acuity, contrast sensitivity, and color vision defects are significant predictors of computer task performance. Visual function parameters of the better eye played a more significant role than parameters of the worse eye, and contrast sensitivity is the most significant predictor of computer task accuracy.

Activities of Daily Living↗
PubMed1996

Radioimager quantification of oligonucleotide hybridization with DNA immobilized on transfer membrane: application to the identification of related sequences.

The radioimager scintillating optical fiber imager was used to quantify the hybridization parameters of a 35-mer oligonucleotide probe with target DNAs immobilized on transfer membranes. The amount of the immobilized target DNA remaining accessible to hybridization (Rt) was shown to be about 4% of the spotted DNA. The time course of the hybridization of a target DNA reacting with an excess of full-match probe exhibited a first-order kinetics, in which rate constant k was the highest for the hybridization temperature close to the calculated Tm. The effect of temperature on the hybridization kinetics of the probe sharing 37 to 100% identity with the immobilized target DNA was assessed: A significant fall of both the rate constant k and Rt values at the plateau was observed when the identity shared by the target DNA and the probe decreased from 100 to 71%. The highest k and Rt values were also obtained for temperatures closest to the calculated Tm. A good estimate of the degree of sequence identity may be calculated from the corresponding hybridization signals. Washing procedure did not improve the discrimination between related sequences, except for closely similar sequences. Practical conclusions for the detection of sequences belonging to gene families are presented.

Base Sequence↗