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At least 865 records · Page 48Linked to original sources
PubMed2006

Prevalence of metabolic syndrome in an elderly Swedish population.

The prevalence of the metabolic syndrome in different elderly European populations has not been well studied. The aim of this study was to measure the prevalence of metabolic syndrome, as well as its individual components, in an elderly Swedish cohort. A random sample of 778 individuals (372 men and 406 women) was selected from a 70-year-old cohort in the H70 study, a gerontological and geriatric population study carried out in Gothenburg, Sweden. The study included medical and treatment history assessments, laboratory procedures and physical examinations to determine the presence of each of the five components of the metabolic syndrome as defined by the National Cholesterol Education Program Adult Treatment Panel III. Of the 508 adults (243 men and 265 women) included in the study, 22.6% had metabolic syndrome. The prevalence was higher in men (26.3%) than in women (19.2%). One third of the total sample had at least one of the five risk factors for metabolic syndrome. High blood pressure (> or =130/85 mmHg or use of antihypertensive/diuretic medication) was the most prevalent risk factor in both men (68.3%) and women (50.2%), while abdominal obesity was the overall second most common risk factor (27.2% of men and 42.7% of women). The prevalence of high fasting plasma glucose (> or =110 mg/dl or use of antidiabetic medication) was 29.0% in men and 19.1% in women. Metabolic syndrome was prevalent in a significant proportion of this elderly Swedish population, highlighting the underdiagnosis of a condition that is important to treat.

Aged↗
PubMed2002

Do tufted capuchin monkeys (Cebus apella) spontaneously deceive opponents? A preliminary analysis of an experimental food-competition contest between monkeys.

A new laboratory procedure which allows the study of deceptive behavior in nonhuman primates is described. Pairs of tufted capuchin monkeys faced each other in a food-competition contest. Two feeder boxes were placed between the monkeys. A piece of food was placed in one of the boxes. The subordinate individual was able to see the food and to open the box to obtain the bait. A dominant male was unable to see the food or to open the box but was able to take the food once the box was opened by the subordinate. In experiment 1, two of four subordinate monkeys spontaneously started to open the unbaited box first with increasing frequency. Experiment 2 confirmed that this "deceptive" act was not due to a drop in the rate of reinforcement caused by the usurping dominant male, under the situation in which food sometimes automatically dropped from the opened box. In experiment 3, two subordinate monkeys were rerun in the same situation as experiment 1. One of them showed some recovery of the "deceptive" act but the other did not; instead the latter tended to position himself on the side where there was no food before he started to open the box. Although the results do not clearly indicate spontaneous deception, we suggest that operationally defined spontaneous deceptive behaviors in monkeys can be analyzed with experimental procedures such as those used here.

Animals↗
PubMed2003

NeuroSys: a semistructured laboratory database.

The inherent complexity of traditional relational database systems is a key obstacle to more widespread use of database technology in the neuroscience community. As an alternative to relational technology, we propose a simpler semistructured data model for documenting laboratory procedures and results. The semistructured data model allows researchers to document their data in an organized, regularly formatted, machine-readable, and network accessible manner, without requiring the services of database professionals. We present proof-of-concept software, consisting of an HTML interface that communicates with a remotely located, semistructured database. We also discuss the importance of standardized terminology and the importance of building flexible data description systems that are more easily adapted and reconfigured to conform with standardized terminologies as they evolve.

Computational Biology↗
PubMed1989

A simple and rapid method to initiate Trypanosoma brucei brucei and T. brucei evansi bloodstream form cultures.

Initiation of cultures of bloodstream forms of trypanosomes from the Trypanozoon subgenus is an established laboratory procedure. The trypanosomes are usually separated from the blood cells of the donor animal by centrifugation on a density gradient (Hirumi et al., 1977) or by differential centrifugation (Hill et al., 1978; Brun et al., 1981; Zweygarth et al., 1982; Baltz et al., 1985). Isolation on an anion exchange column (Lanham and Godfrey, 1970) has been little used for this purpose. We describe a simple and rapid method for the initiation of trypanosome bloodstream form cultures from infected host blood, avoiding centrifugation and anion exchange column procedures. Two T.b. brucei stocks, CP 271 and CP 547, and two T.b. evansi stocks, CP 1134 and CP 2087, were used. Stock CP 271 was isolated in 1980 from a goat in Matuga/Kenya, stock CP 547 was isolated in 1985 from a naturally infected bovine in Jilib/Somalia. The two T.b. evansi stocks were both isolated from camels, stock CP 1134 in 1979 in Kulal/Kenya, stock CP 2087 in 1980 in the Sudan.

Animals↗
PubMed1991

A method to detect proteinase activity using unprocessed X-ray films.

Routine assays to detect proteinases in biological samples are generally tedious and time-consuming. To expedite the recognition of proteinases, we have developed an assay utilizing the gelatin on the surface of an unprocessed Kodak X-Omat AR film as the proteolytic substrate. A positive reaction is indicated by a clear zone on the film after it has been rinsed with running water. This proteinase assay has been found to be inexpensive, rapid, and simple. Besides its ease of use, this assay has been found to be quantitatively reproducible with a well-defined endpoint. More importantly, this assay method is applicable to a variety of proteolytic enzymes under diverse pH (5-8.5) and salt conditions (up to 5 M NaCl) and has a sensitivity similar to that of azocoll. Since the assay does not require sophisticated equipment, it is useful as a general laboratory procedure.

Azo Compounds↗
PubMed1993

Degradation of angiotensin I in the endothelium and smooth muscle of the rat aorta.

In homogenates of the endothelium and smooth muscle cum adventitia of the rat aorta, exogenous angiotensin (ANG) I was found to be degraded to des-aspartate-ANG I (des-Asp-ANG I) instead of ANG II. ANG II and ANG III were not detectable in either of the homogenates after 5, 10 and 30 min of incubation with the decapeptide. However, both the homogenates were able to catalyse hippuryl-L-histidyl-L-leucine (HHL) to hippuric acid and the catalysis was completely inhibited by 3 microM captopril. The data show that the angiotensin converting enzyme (ACE) present in the homogenates of rat aorta, prepared by normal laboratory procedures, is not able to hydrolyse ANG I to ANG II. This finding has important consequences in the study of vascular ACE as the assay of the enzyme is often carried out using crude homogenate and HHL or other artificial substrates. In addition, the aminopeptidase that degraded ANG I to des-Asp-ANG I was not inhibited by either amastatin or bestatin, indicating that it was not aminopeptidase A or B. Together with the recent findings of other investigators which show that the de novo production of ANG II in vascular tissues is stimulated and inhibited by beta- and alpha-agonists, respectively, our present data may suggest that production of vascular ANG II occurs only in intact tissues and is probably under adrenergic regulation.

Amino Acid Sequence↗
PubMed1976

Anticonvulsant activity of delta9-tetrahydrocannabinol compared with three other drugs.

Delta9-tetrahydrocannabinol (THC) was compared with diphenylhydantoin (DPH), phenobarbital (PB) and chlordiazepoxide (CDP) using several standard laboratory procedures to determine anticonvulsant activity in mice, i.e., the maximal electroshock test (MES), and seizures induced by pentylenetetrazol, strychnine and nicotine. In the MES test, THC was the least potent and DPH the most potent blocker of hind limb tonic extensor convulsions whereas THC was the most potent and DPH the least potent in increasing the latency to this response and in preventing mortality. Seizures and mortality induced by pentylenetetrazol or by strychnine were enhanced by THC and DPH and were blocked by PB and CDP. In the test with nicotine, none of the four anticonvulsant agents prevented seizures; DPH was the only one which failed to increase latency; THC and DPH were less potent than PB and CDP in preventing mortality. THC most closely resembled DPH in the tests with chemical convulsant agents, but a sedative action of THC, resembling that of PB and CDP, was indicated by low ED5 0 for increased latency and for prevention of mortality in the MES test.

Animals↗
PubMed1981

Hyperactivity induced in rats by long-term isolation: further studies on a new animal model for the detection of antidepressants.

Male rats isolated at the time of calcification of the incisors show after 10 months of social deprivation a marked and sustained increase in locomotor activity together with other behavioural changes. The ages of separation as well as the prolonged isolation period appear to be critical with regard to the stability of the behavioural syndrome and to the sensitivity of the rats to different pharmacological treatments. The locomotor activity of solitary housed rats is selectively blocked after acute treatment with several antidepressants which are inactive according to the traditional laboratory procedures for detecting the activity of this class of drugs. Handling of the isolated animals for 30 consecutive days produces, on the other hand, a permanent attenuation of the hyperactivity syndrome. It is suggested that the present animal model may be of value for the detection of antidepressants and for elucidating the role of an important social variable in the production of neurochemical changes associated to depressive disorders.

Animals↗
PubMed1986

Intracerebral infection of mice with ovine strains of Chlamydia psittaci: an animal screening test for the assay of vaccines.

Intracerebral inoculation of mice with the A22 strain of ovine C. psittaci gave a reproducible non-lethal infection; multiplication of the inoculum could be quantitated by titration of mouse brain extracts in tissue culture. Mice which had recovered from infection, or which had been inoculated subcutaneously with living organisms of A22 strain, showed solid resistance to intracerebral challenge infection. However, subcutaneous inoculation of formalin-inactivated chlamydia showed little protective effect unless given in very high dosage. Inactivated vaccines of the heterologous ZC113 strain gave better, but still incomplete, protection against A22 challenge infection than did the homologous inactivated vaccine. The implication of these findings is discussed. The mouse intracerebral protection test appears to be a suitable laboratory procedure for assessing the potency of vaccines against enzootic ewe abortion and for comparing the immunological cross-protection between the various strains of C. psittaci currently found in the natural disease in sheep.

Animals↗
PubMed1990

A method for isolating neutrophils from moderate volumes of human blood.

The Flow Laboratories procedure for isolating polymorphonuclear leukocytes (PMNs) from human blood whereby whole blood is centrifuged through Mono-Poly resolving medium (MPRM) has been modified. Using this modification, as much as 30 ml of whole blood could be processed in a single centrifuge tube, and erythrocyte contamination of the final PMN suspension was reduced significantly. PMN suspensions were composed of 96% neutrophils, and neutrophil recovery was 42-55% depending upon the volume of blood processed. Cell viability was 98% as determined by trypan blue exclusion. Greater than 99% of the neutrophils were spherical suggesting that the neutrophils were not primed during isolation.

Cell Separation↗
PubMed1976

A systematic approach to the control of esthetic form.

A systematic, orderly approach to the problem of establishing harmonious phonetics, esthetics, and function in fixed restorations has been described. The system requires an initial investment of time in performing an adequate diagnostic waxing, but recoups that time in many clinical and laboratory procedures. The method has proved a valuable asset in fixed prosthodontic care. The technique can be expanded and combined with other techniques with a little imagination and artistic bent.

Denture Design↗
PubMed1976

An individualized impression tray utilizing the patient's existing denture.

This technique utilizes patients' existing dentures to construct individualized impression trays. Some of the advantages are: (1) the trays are made within 30 minutes; (2) final impressions may be made at the first appointment; (3)it is an inexpensive and uncomplicated laboratory procedure readily taught to dental auxiliaries. (4) chair time is better utilized by both the dentist and patient.

Dental Impression Technique↗
PubMed1979

Casting a gold alloy to embedded precision attachment metals.

The technique for casting a gold alloy to embedded attachment metals has been described. The joints of gold alloy cast to commercially available attachment metals were examined with a metallurgic and a scanning electron microscope. The investigation indicated that an uninterrupted gapless joint is possible, and that some diffusion occular along the interfaces with some attachment metals. In view of these findings, it is concluded that this technique can be recommended as a dental laboratory procedure.

Dental Alloys↗
PubMed1980

The combined reversible hydrocolloid/irreversible hydrocolloid impression system.

1. Dentloid, a reversible hydrocolloid which had been altered to bond to irreversible hydrocolloid, demonstrated a bond with three irreversible hydrocolloids tested in combination with it. 2. Two conventional reversible hydrocolloids exhibited such weak bonding with irreversible hydrocolloid that it was impossible to make impressions with them. 3. The three irreversible hydrocolloids exhibited different bond strengths with Dentloid. 4. The Dentloid/irreversible hydrocolloid combination with the lowest bond strength exhibited the lowest dimensional stability. 5. Combined impressions of Dentloid with two of the three irreversible hydrocolloids exhibited dimensional stability that is a clinically acceptable. 6. Combinations of Dentloid with irreversible hydrocolloids not covered in this report should be verified for acceptable dimensional stability before clinical use. 7. The combination technique, in itself, proved to be easy and practical and overcomes many of the shortcomings inherent to conventional reversible hydrocolloid impression techniques. 8. Strict adherence to laboratory procedures for pouring a cast is as critical as for the conventional technique.

Chemical Phenomena↗
PubMed1983

Predictable anterior determinants.

A method has been proposed to develop anterior determinants that are comfortable and pleasing to the patient, who participates in the development of their anterior esthetics and phonetics. This activity encourages final acceptance. Because the teeth are preoperatively restored to their final size and shape, a more conservative preparation results. The resultant provisional restorations provide guidelines for the final ceramometal restorations. The laboratory procedures are also simplified by detailed records and improved communication. The copings are finished to their proper dimension, and it becomes readily evident whether metal lingual surfaces should be provided. The porcelain can be applied in less time since the lingual concavity and incisal edge are "pre-formed." Usually fewer porcelain bakes are required due to uniform compensation for shrinkage. The incisolingual index creates a more positive and accurate form for the proposed restorations because it is mounted directly and securely to the articulator and not hand-positioned. The disadvantage of multiple, early appointments is far outweighed by the quality provided and the reduced time in adjustments. In final analysis this technique is less costly, ensures better esthetics and phonetics within less time, and creates better patient-dentist-technician relationships.

Crowns↗
PubMed1985

Effect of manipulative variables on the accuracy of crown wax patterns.

An instrument was developed to carve wax patterns in a reproducible manner. The methods of wax application to the die and wax removal during carving were similar to routine laboratory procedures. The wax patterns were invested in stone with the dies on which they were prepared, and sectioned to allow the determination of their adaptation on sectioned samples. Shrinkage of wax patterns on dies was found to create a marginal gap at shoulders and bevels. Further shrinkage observed after removal from the die was attributed to relaxation of elastic stresses in the wax. Carving of bevels improved adaptation to the die for samples with large gaps at the shoulder. This improved adaptation can be attributed to plastic deformation in the wax bevel. Remodeling of pattern margins was found to improve adaptation to the die, especially if carried out after the pattern was removed and replaced on the die. Remodeling the margin should involve heating with a spatula of a narrow band of wax around the margin up to the axial die wall over the entire shoulder width.

Chemical Phenomena↗
PubMed1985

Laminated single impression technique for cast posts and cores.

A laminated single impression technique for cast post and core has been described. Its advantages are the ease and versatility with prefabricated or customized post techniques (Fig. 14) and the one-step registration of single or multiple divergent canals. Its disadvantage is the necessity for additional laboratory procedures.

Crowns↗
PubMed1987

Bonding of dental porcelain to ceramic-metal alloys.

The bond strength of porcelain to the four gold alloys and the three nonprecious alloys was tested with a simplified pull test method, having wide test surfaces. The tests showed that all gold alloys tested were suitable for fusing porcelain. The bond strength in nonprecious alloys was somewhat lower and the location of the fracture lines was more variable. It seems that nonprecious alloys are more sensitive to laboratory procedures. The bond strength and the location of the fracture line had a good correlation in all metal alloys.

Dental Alloys↗