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PubMed2006

Contaminated sediment testing with the bivalve Mulinia lateralis: culture refinement for organism availability.

Availability of test species for estuarine benthic assessment is limited; therefore, a method was developed by the U.S. Environmental Protection Agency for using the dwarf surf clam (Mulinia lateralis) to identify adverse biological effects of bulk estuarine sediments. A multilaboratory evaluation of the draft method resulted in favorable responses from the participants with respect to general testing and handling of the clam. However, availability of good-quality test organisms was limited. An investigation of culture techniques determined that culture vessel topography dramatically influenced survival, because larvae accumulated in bottom depressions. Conditioning of brood stock was enhanced by algae naturally containing both 20:5n-3 and 22:6n-3 fatty acids. Survival of larvae to metamorphosis at 14 d postspawn was greatly increased by maintenance at a lighting of 734 lux with addition of gradually increasing amounts of Isochyris galbana and Chaetoceros calcitrans. Greater than 50% survival of 600 juveniles to testing size by 14 d postmetamorphosis was accomplished by intermittent delivery of algae 12 times per day in a total of 13 L of seawater. By 21 d postmetamorphosis, an additional 27% achieved testable size. As a result of identification of these culture parameters, test bivalves can be readily available to improve predictions of adverse biological effects on benthic communities beyond those presently determined through amphipod exposures.

Animals↗

PubMed2004

Compensatory load redistribution of horses with induced weightbearing hindlimb lameness trotting on a treadmill.

REASONS FOR PERFORMING STUDY: The compensatory mechanisms of horses with weightbearing hindlimb lameness are still not fully understood. HYPOTHESIS: That weightbearing, unilateral hindlimb lameness would not only alter stride characteristics to diminish structural stress in the affected limb but also induce compensatory load adjustments in the other supporting limbs. OBJECTIVE: To document the load and time shifting mechanisms of horses with unilateral weightbearing hindlimb lameness. METHODS: Reversible lameness was induced in 8 clinically sound horses by applying a solar pressure model. Three degrees of lameness (subtle, mild and moderate) were induced and compared with the nonlame (sound) control measurement. Vertical ground reaction forces were recorded for all 4 limbs simultaneously on an instrumented treadmill. RESULTS: Compared to the sound situation, moderate hindlimb hoof lameness induced a decrease in stride duration (-3.3%) and stride impulse (-3.1%). Diagonal impulse decreased selectively in the lame diagonal stance (-7.7%). Within the diagonal limb pair, vertical impulse was shifted to the forelimb during the lame diagonal stance (+6.5%) and to the hindlimb during the sound diagonal stance (+3.2%). Peak vertical force and vertical impulse decreased in the lame limb (-15%), but only vertical impulse increased in the contralateral hindlimb (+5.7%). Stance duration was prolonged in both hindlimbs (+2.5%). Suspension duration was reduced to a greater extent after push-off of the lame diagonal limb pair (-21%) than after the sound diagonal limb pair (-9.2%). CONCLUSIONS: Four compensatory mechanisms could be identified that served to reduce structural stress, i.e. peak vertical force on the affected limb: 1) reduction of the total vertical impulse per stride; 2) diagonal impulse decreased selectively in the lame diagonal; 3) impulse was shifted within the lame diagonal to the forelimb and in the sound diagonal to the hindlimb; and 4) the rate of loading and peak forces were reduced by prolonging the stance duration. POTENTIAL RELEVANCE: Load shifting mechanisms are not only effective in diminishing peak forces in the affected limb, but also suppress compensatory overload in other limbs. Selected force and time parameters allow the unequivocal identification of the lame limb. Future studies have to examine how far these compensatory mechanisms may be generalised for other defined orthopaedic problems in the hindlimb.

Adaptation, Physiological↗

PubMed1994

Discrimination between patients with acoustic neuroma and with peripheral vestibular lesion by human posture dynamics.

A group of normal subjects (n = 17) was compared with two groups of patients, either with vestibular neuritis (n = 18) or with acoustic neuroma (n = 35) by means of posturography when stance was perturbed with vibrators attached to the calf muscles. Dynamic control of human posture was quantified by means of system identification, and the characteristic parameters of swiftness, stiffness, and damping of a transfer function from vibration to force platform response were used for further comparison. Fisher linear discriminant analysis was used to distinguish sets of parameters characteristic of each disease. Hence it was possible to distinguish the vestibular neuritis group both from the normal group (p < 0.01), and from the patients with acoustic neuroma (p < 0.001). The normal group was characterized by a different postural performance, with higher swiftness and stability parameters (stiffness, damping) than those of the patient groups. These findings indicate that there are differences in the dynamic control of posture between the two patient categories, which may require the development of differentiated rehabilitation programs.

Adult↗

PubMed1987

Repeatability of kinetic and kinematic measurements in gait studies of the lower limb amputee.

During the last few years considerable attention has been given to the use of gait analysis as a tool for clinical use. The instrumentation for measurement of the kinetics and kinematics of human locomotion was originally designed for research use. Extension of its use into the clinical field calls for simplified methodology and clearly defined protocols with precise identification of the relevant parameters for the analysis. Force platforms, TV-computer and pylon transducer systems were used for collection of kinetic and kinematic data of five normal subjects, 10 below-knee, 10 above-knee and one hip disarticulation amputee. The repeatability tests showed significant differences in the measured parameters. These variations are attributed to the methodology of the analysis and the step to step variation of the subjects' gait. Differences in the degree of step to step variation between various amputee and normal subjects are quantified. In this presentation the capability of present day systems to perform repeatable gait measurements is discussed. A computational method for determination of representative measurements for the purposes of biomechanical evaluation and comparison as well as quantification of the degree of repeatability is described.

Adult↗

PubMedDate not supplied

Chromosome changes in hematologic malignancies.

Evidence has now accumulated that chromosome changes are among the critical events that lead to malignant transformation of cells. More sophisticated analysis of clinical and cytogenetic parameters will lead to identification of additional subtypes of hematologic neoplasms such as t(15;17) APL or Ph1-positive CML. This differentiation has both diagnostic and prognostic importance. Cytogenetic studies currently in progress may reveal etiologic factors in malignant transformation; occupational exposure to potential mutagens, previous cytotoxic therapy, ethnic background, or a family history of cancer may correlate with specific chromosome abnormalities and specific subtypes of leukemia and lymphoma. As our knowledge of the human gene map increases, we expect to be able to relate changes in the affected chromosomes to biochemical abnormalities in the malignant cell. This will improve our understanding of how selected cells gain a proliferative advantage through malignant transformation, and it will aid in the precise classification of these diseases and thus lead to the design of more specific forms of therapy.

Chromosome Aberrations↗

PubMed2002

A rapid and improved method for the detection of Vibrio parahaemolyticus and Vibrio vulnificus strains grown on hydrophobic grid membrane filters.

DNA probe-based detection methods were developed and characterized as an alternative to time-consuming and less specific conventional protocols. Digoxigenin-labeled probes were prepared by polymerase chain reaction amplification of the targeted sequences in the specific amplicons generated from genomic DNA. Specific probes with high yields were generated for the detection of the tlh gene of Vibrio parahaemolyticus and the cth gene of V. vulnificus. Colony (Southern) hybridization analyses were carried out using hydrophobic grid membrane filters (HGMFs) to allow biotype-specific differentiation of the two species. Eight strains of V. vulnificus and five strains of V. parahaemolyticus, including one standard (ATCC) strain of each biotype, were examined. Colony lysis, hybridization, and nonradioactive detection parameters were optimized for identification of the target biotypes arranged on the same HGMF and also on a conventional nylon membrane, thereby confirming the specificity of the probes and the comparative usefulness of the HGMFs. The experimental procedure presented here can be completed in 1 day. The protocol was designed specifically to identify the target Vibrio spp. and could potentially be used for the enumeration and differentiation of V. parahaemolyticus and V. vulnificus in foods.

DNA Probes↗

PubMed1999

[Determination of reference ranges and effect of maternal and fetal factors on insulin and C-peptide level in umbilical cord blood].

OBJECTIVE: The risks of pregnancy caused by maternal diabetes are well known. Patients with unrecognized gestational diabetes mellitus (GDM) represent a special problem. The aim of our study was to find out, whether the determination of insulin and C-peptide in cord blood serum offers a valuable tool for retrospective analysis. MATERIAL AND METHODS: In 600 paired serum samples from maternal venous blood and neonatal cord blood insulin and C-peptide were determined radioimmunologically. A reference group consisting of 338 mothers and their newborns was established by exclusion of all patients with known pregnancy complications. RESULTS: Positive correlations could be identified between fetal insulin and fetal C-peptide, as well as correlations of these parameters with birth weight and body length, with maternal values of insulin, C-peptide, body-mass index, weight, and weight gain during pregnancy respectively. Increased levels of cord serum insulin were found in complicated pregnancies as well as in patients with previous pregnancy losses, preterm deliveries or stillbirths. CONCLUSIONS: Cord serum insulin and C-peptide were found to be useful parameters for immediate postnatal identification of impaired glucose tolerance during the course of pregnancy.

Adolescent↗

PubMed1999

Regional differences in mortality: a comparison between Austria, Hungary and Switzerland.

BACKGROUND: Important differences in mortality rates exist even between neighbouring countries. This should facilitate the identification of the lifestyle parameters underlying these differences. The mortality rates obtained in Hungary, Austria and Switzerland were compared. METHODS: The mortality rates for all-cause, total cardiovascular, total cancer and stroke mortality were obtained from a special tape from WHO. Nutritional data were obtained from FAO food balance sheets and from dietary surveys. Gompertz and polynomial equations were calculated from the age-specific mortality rates. FINDINGS: Great differences in mortality exist between the three countries. In the period from 1950 until 1995 mortality decreased in Austria and Switzerland, but increased in Hungary. In men, total cancer and total cardiovascular mortality also increased markedly in Hungary during the last 20 years. Hungary has a lower dietary P/S ratio, a higher level of animal/vegetal fat and a lower consumption of fruit than Austria and Switzerland, combined with a high level of salt consumption. The level of cigarette smoking is similar in Hungary and Switzerland. The increase in mortality rate in Hungary is less pronounced in women than in men. INTERPRETATION: The major differences in lifestyle between the three countries concern socio-economic and nutritional patterns. Epidemiological evidence favours nutrition as the most important determinant of the differences in mortality rates between the three countries.

Adult↗

PubMed2001

[Immunological aspects of laboratory diagnosis of chronic urticaria].

High prevalence of allergic diseases necessitates search for new methods of laboratory diagnosis thereof. We studied the diagnostic significance of the count of cells expressing low-affinity receptors to IgE (CD23+ cells) and compared this test with skin tests with non-infectious allergens and measurement of total serum IgE. 104 patients with various forms of chronic relapsing urticaria were examined. The count of CD23+ cells was markedly increased in atopic urticaria. The increase in the count of these cells and correlation with the results of skin test were less expressed in infectious allergic urticaria. In other forms of chronic urticaria characterized by negative results of skin tests the count of CD23+ cells was normal. The level of total serum IgE was low virtually in all patients. Hence, the count of cells carrying low-affinity receptors to IgE is highly informative, detecting IgE-mediated reactions in the patients, though this parameter does not allow identification of the allergen. This test can be used in complex with other methods of allergodiagnosis, particularly in cases when skin tests are for this or that reason impossible.

Adolescent↗

PubMedDate not supplied

[Quantification of physiological kyphosis adults according to the roentgenogramometry data].

The shape of thoracic physiological kyphosis was studied based on data obtained through the examination of 120 patients who had presented no complaints regarding thoracic spine. As a result, a quantitative description of a normal curvature for thoracic kyphosis was elaborated. The study addressed such issues as the impact of separate segments on the development of kyphosis, with the identification of relevant quantitative parameters. In addition, sex-related differences of the quantitative parameters describing the form of thoracic spine were determined. The study analyzed tendencies in the curvature transformation during the life period of 16-30 years of age.

Adolescent↗

PubMed2002

Total correction of tetralogy of Fallot: late clinical follow-up.

Forty-five years after the first repair of tetralogy of Fallot we have sufficient data to describe the post-surgical history of these patients in terms of survival, quality of life and delayed complications. The long-term results of surgical repair during infancy and childhood are good in terms of health assessment and exercise capacity. However arrhythmias and right ventricular dysfunction secondary to ventriculotomy and residual pulmonary regurgitation characterize the delayed follow-up. The identification of the clinical parameters which are predictive of premature ventricular dysfunction and electrical instability is a primary aim of clinical follow-up.

Adolescent↗

PubMedDate not supplied

[Clinical and physiological studies of flight personnel with 1st stage hypertensive disease].

An examination of the functional state of the cardiovascular system of 30 pilots with hypertension of the I stage showed that the parameters expressing an increase of the blood ejected to the vascular bed were the most informative hemodynamic and polycardiographic values. It was found that the stroke volume, cardiac output, volume velocity of the ejection, power of the left ventricle, energy expenditure per I 1 of cardiac output and time of the isometric contraction phase increased. The interactions of the cardiac output and peripheral resistance made it possible to distinguish hemodynamic modifications of the hypertensive disease: cardiac-increased cardiac output (15 pilots), vascular--increased peripheral resitance (11 pilots) and mixed--simultaneous increase of both parameters (4 pilots). The identification of the modification is important for proper treatment and expertise.

Aerospace Medicine↗

PubMed2003

[Alteration of bone metabolism in HIV-infected patients treated by HAART].

For several years already, a growing number of studies reports modifications in the bone metabolism among HIV-infected patients. Some of these studies, published even before the use of HAART, involved the infection itself. With the experience already available as concerns HAART, antiretroviral treatments (ART) seem however to be called into question. Data are divergent yet. Some studies tend to invalidate the collected data about the harmful role of HAART and prove the absence of effect or even the beneficial action of ART on bone. Moreover, the three important classes of ART are implied, even if the proteases inhibitors are most commonly charged. Pathogenic mechanism remain hypothetical. While the impact on morbidity seems to be weak for the time being, long-term repercussions are still unknown, in particular when children are concerned. In such conditions, it appears difficult to set up coherent politics of screening, prevention and treatment. Nevertheless beyond the divergences, the multifactorial character of alteration of HIV-infected patient's bone metabolism seems to be undeniable. The identification of the different parameters should in the future clarify the situation and enable the publishing of exact criteria of screening, prevention and treatment.

Antiretroviral Therapy, Highly Active↗

PubMedDate not supplied

[Uses of vaginal pH measurement for prevention of premature labor. Results of a prospective study].

UNLABELLED: The influence of the microflora of the vagina and cervix has been undervalued for the induction of premature birth. Examination of the microbiological problem by determination of the vaginal pH in combination with the microflora (Chlamydia trachomatis, Mycoplasma hominis, Ureaplasma urealyticum). Report of the outcome of 161 prospective, ad the beginning normal pregnancies in comparison of 200 primary hospitalized pregnancies with symptoms of imminent premature birth. CONCLUSION: The vaginal pH is a very useful parameter of screening for identification of disturbances of the microflora in practice. In cases of pathologic pH (> 4.5) it is possible by therapy to reduce the premature birth rate.

Acid-Base Equilibrium↗

PubMed1975

[Quantitative study of serotonin-containing cells in fetal rabbit duodenum].

In order to attempt identification in vitro of parameters involved in the cellular differenciation, it was necessary to possess a standard material with identical content and distribution of serotonin cells; these two properties are investigated in this paper. Falck's technic is the only sensitive and specific method in demonstrating serotonin young cells devoid of argentaffinity. From 21, 22, 23 and 25 days old rabbit foetuses, 10 mm length duodenal pieces were treated according to Falck and sections serially cut at 8 microns. Some of these specimens were divided prior to Falck treatment in two pieces 3 mm away from the pylorus and in each piece 200 paraffin sections were cut at 8 microns beginning by adjacent ends and progressing in opposite direction. The number of EC sections in 400 whole transverse sections were determined for each foetus. Great variations were observed from one foetus to another, along the intestine, with weight and age. The Student-Fisher test applied to two consecutive pieces of the same duodenum gathering foetuses in groups of 5 animals did not show significative differences from a group to another. Thus, this material can be employed for comparisons under experimental conditions.

Animals↗

PubMed1992

Assessment of the otoscopic skills of general practitioners and medical students: is there room for improvement?

Ear, nose and throat problems are common in general practice, yet undergraduate and postgraduate teaching in the subject is variable and often sparse. The assumption that direct experience in otoscopy in practice will compensate for inadequate previous tuition was tested by assessing a group of 53 general practitioners and 59 medical students. Confidence in otoscopy was assessed using a visual analogue scale and skill was assessed by clinical examination of four ears. Otoscopy was divided into identifying the tympanic membrane, distinguishing a normal from an abnormal membrane and identifying specific features of the membrane. The medical students and general practitioners were comparable in both confidence and skill for all parameters except skill in identification of specific features of the tympanic membrane, in which the students' ability was greater (Student's t-test, P < 0.01). In both groups the percentage of false negative observations was reassuringly low--for students the mean was 3.0%; and for general practitioners 4.3%. There is room for improvement in general practitioner's training in otoscopy. Supervised tuition is essential and cannot be compensated for by unsupervised experience. More involvement with ear, nose and throat problems in vocational training or attendance at continuing education courses is suggested.

Clinical Competence↗

PubMedDate not supplied

In situ monitoring of soil dissolution dynamics: a rapid and simple method for determining worst-case soils for cleaning validation.

A common approach utilized in validating the cleaning of multi-product equipment is to challenge the cleaning cycle with the hardest-to-clean, or "worst-case", soil. The worst-case soil is often determined through bench-scale experiments. These experiments can be tricky and time-consuming, especially when the dissolution dynamics of the soils are characterized by crossovers beyond the limit of visual detection. This paper describes a simple in situ method for monitoring soil dissolution dynamics and rapidly determining worst-case soils for cleaning validation. The method utilizes the real-time response of electrical conductivity to identify crossovers and to determine the optimal time for endpoint analysis. The results address the sensitivity and reproducibility of the method and the identification of critical experimental parameters. The dissolution dynamics of several parenteral products are compared.

Drug Contamination↗

PubMed2004

Metabolic syndrome--practical approach.

The diagnosis of metabolic syndrome is based on identification of the following parameters: abdominal obesity, triglycerides, HDL-cholesterol, blood pressure, fasting glycemia, as recommended by ATP III. In order to simplify the clinical practice, at least two parameters should be screened for. The most frequent couple, easy to be determined in practice, is hypertensive waist, followed by hypertriglyceridemic waist, hypertensive dyslipidemia, dysglycemic dyslipidemia and hypertensive dysglycemia. Based on these couples the next step would be to identify the triads that diagnose the metabolic syndrome. A global assessment of cardiovascular risk should be made. Suggested method is to apply the Framingham Score. Therapeutic intervention is structured according to levels of cardiovascular risk. Clinical management is structured on THEME Programs (therapy, education, monitoring, evaluation), applied to all risk factors.

Dyslipidemias↗