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PubMed1980

Properties of spermatozoa from normospermic and oligospermic human semen fractionated on columns of discontinuous gradients of albumin.

One hundred and twenty-eight samples of human semen, divided into four groups according to sperm counts, were fractionated on two types of columns of discontinuous gradients of bovine serum albumin (3%, 15%, or 7.5%, 17.5%). In addition to morphology and motility, protein and DNA contents of spermatozoa as well as microscopical pictures of their sediments were examined in order to assess sperm sensitivity to damage in the course of common isolation procedures. The proportions of morphological normalcy and motility grades within the groups were higher in the bottom column fractions than in the middle ones; both showing prevalence over parent semen. Motility percentages were also higher in the bottom than in middle fractions, but no prevalence over parent semen was observed. Protein and DNA contents of spermatozoa were similar in the two fractions within the same group. Comparison between groups revealed an increase in percentages of normal morphology and motility and a decrease in protein and DNA with elevation of sperm density. Microscopic examinations revealed similar degrees of contamination in both fractions which were more abundant in oligospermia than in normospermia. It is suggested that sperms with better morphology and motility are as sensitive to common laboratory procedures as cells of lower quality originating from the same specimen.

Cell Fractionation↗
PubMed1991

Diazepam preference in males with and without an alcoholic first-degree relative.

The relationship between family history of alcoholism and risk for benzodiazepine abuse was examined by assessing the reinforcing and subjective effects of diazepam (DZ; 4-28 mg) in 14 normal (i.e., nonalcoholic) males with a first-degree alcoholic relative (family history positive; FHP) and in 13 control subjects without alcoholic relatives (FHN). Reinforcing effects were measured using a double-blind preference procedure in which subjects first sampled DZ and placebo (PL) and then chose the substance they preferred. Subjects were also allowed to select the dose of drug they preferred on each choice session. The subjective effects of DZ were assessed using standardized self-report questionnaires. Neither group chose the DZ more often than PL. The FHP group chose DZ slightly (but not significantly) more often than the FHN group (mean choices FHP 1.42 vs. FHN 1.15 out of 3 choice options), and they chose slightly (but not significantly) more doses of DZ within sessions (FHP 25 mg vs. FHN 18 mg). The groups did not differ in their responses to DZ on other measures (e.g., subjective drug effects or drug liking). To the extent that laboratory procedures such as the one used here provide a model for assessing the abuse liability of drugs, these results do not provide strong evidence that males with a family history of alcoholism have an elevated risk for developing benzodiazepine abuse or dependence.

Adult↗
PubMed2003

Study of fractionation and potential mobility of metal in sludge from pyrite mining and affected river sediments: changes in mobility over time and use of artificial ageing as a tool in environmental impact assessment.

Sludge from mining exploitation can be a source of land and water contamination in the adjacent zone. Accidents such as the break of waste mining pools in the Aznalcollar Mine (Seville, Spain) in 1998 produce important ecological disasters. In this work is presented a study of the evolution of aqua regia leachable concentration and mobility of metals in sediment samples of Guadiamar River basin from the accident date up to 2001. The application of BCR standard extraction procedures provides valuable information about the mobility and toxicity of the spill and the metal mobility in Guadiamar River polluted sediments. As a rule, themobility of several metals in the initial sludge (sulphides) is low, except for copper. Otherwise, the results of aqua regia leachable concentration and mobility of metal obtained for sediments samples indicate that the cleaning and inertisation works carried out in the zone have been adequate but insufficient, being the metal levels observed in the zone are higher than natural levels. To establish the initial impact of the spill and the mobility changes with time, mineralogical composition of the pyritic sludge and its evolution after the natural weathering and after the induction, of accelerated ageing processes by light and temperature was studied in the laboratory. Oxidation of initial sulphides to sulphates was observed. Both environmental and laboratory oxidation of the metallic sulphides increase the mobility of all metals, especially of copper, zinc and lead. The proposed laboratory procedure allows to predict the changes in mobility and therefore in toxicity that can occur at short or long term after exposure of sludge at environ-mental conditions. The mobility results in sludge and sediment samples are interpreted in terms of the mineral composition of the samples.

Chemical Fractionation↗
PubMed1997

Fibrous capsule formation in response to ultrahigh molecular weight polyethylene treated with peptides that influence adhesion.

A wide variety of hard tissue substitute materials for reconstruction have been designed for use in dental and orthopaedic procedures. Most of the literature provides information on the osteocompatibility of these materials, and not on soft tissue compatibility. The bone bonding strength of the materials is relatively high, but there seems to be a lack of bonding properties with soft tissue which results in the formation of fibrous encapsulation. This lack of soft tissue bonding can lead to implant failure. Therefore in order to study how artificial materials may remain in the body for long periods of time and remain functional, it is vital to understand the fibrous tissue encapsulation process. Ultrahigh molecular weight polyethylene coated with RGD, RGE, Poly-L-Lysine, or saline was implanted into Sprague Dawley rats either intraperitoneally or subcutaneously for 12 weeks. Aseptic surgical techniques were followed according to standard laboratory procedures. Blood was collected weekly for the first 8 weeks and at 12 weeks, and analyzed for lactate dehydrogenase activity to assess muscle wasting and compatibility. Lactate dehydrogenase activity was elevated at weeks one and two for groups implanted with materials, in comparison to control unoperated animals. From weeks 3-12, the LDH activity was similar in all groups indicating that there was no adverse response to the implanted material. The implants were harvested at the end of 12 weeks, and the fibrous capsule was screened histologically to determine thickness and cell types at the interface. The results clearly showed that the implants that were placed subcutaneously had a less extensive fibrous and vascular tissue formation, than those implanted intraperitoneally. The results also indicated that the location of the implant intraperitoneally, determined the extent of the fibrous tissue formation. The implanted materials coated with RGD and Poly-L-Lysine had thicker fibrous capsule formation than RGE coated implanted at both the subcutaneous and intraperitoneal sites. The results also suggest that the implant-interface contained fewer inflammatory cells when the implants were placed subcutaneously. The overall results indicate that more than surface charge or coating govern the formation of fibrous tissue in vivo.

Amino Acid Sequence↗
PubMed1995

A pseudo-outbreak of salmonellosis.

during July 1991, a single laboratory reported an increased number of an unusual salmonella isolate. An outbreak control team was convened. A case was defined as an individual with diarrhoea from whose faecal sample Salmonella hadar was isolated after 1 July 1991. By 30 July, 90 isolates had been identified and 57 persons interviewed including 39 primary cases. Interviews failed to identify any common features among the cases. A review of the laboratory procedures revealed that the selenite enrichment medium was inoculated using the spoon from the stool collection kit after it was used to emulsify the faecal sample with saline for microscopy. Salmonella hadar was isolated from this saline. Once this practice was stopped, no further isolates of S. hadar were made. This pseudo-outbreak is a powerful reminder to verify the existence of an outbreak, especially when epidemiological data are inconsistent.

Adolescent↗
PubMed2004

Importance of the direct fresh examination in the diagnosis of cutaneous sporotrichosis.

BACKGROUND: To date the direct fresh examination has not been considered, except by a few authors, as a valid laboratory procedure for the diagnosis of cutaneous sporotrichosis. METHODS: Forty-two patients with cutaneous sporotrichosis (36 lymphangitic and six fixed) were studied. Pus was obtained through digital compression of opened lesions followed by collection with a spatula and examination of the material between the slide and the coverslip. Cultures on Sabouraud's glucose agar slants with cloramphenicol and cicloheximide were made in all cases. RESULTS: Direct, fresh examination asteroid bodies of Sporothrix schenckii were found in 85.7% of the cases, which allowed the authors to immediately diagnose the disease. Cultures confirmed the diagnosis in 95.2% of the patients. CONCLUSIONS: Fastness, simplicity and low cost of the fresh examination lead us to recommend systematic use of the method for primary diagnosis of the disease, mainly at first level public health laboratories.

Adolescent↗
PubMed1990

[Quality control of essential oil of muscat sage (Salvia sclarea) during laboratory and industrial preparation. IV. Causes of color changes].

Essential oils of muscat sage--of various habitats in different developmental stages as well as the essential oils prepared with half industrial and laboratorial procedures--have been studied. It has been found that compositions of essential oils do not differ significantly, the difference is only in such an extent that could be expected on the ground of environmental and ontogenetic effects. On the basis of tests it has been established that formation of brown oil is in connection with content of copper of apparatus (boiler, tube); Therefore applications of vessel and connections containing copper or copper impurities must be avoided in preparation of the clear essential oil.

Color↗
PubMed2000

Application of PCR to the identification of dermatophyte fungi.

Infection of the keratinised tissues (skin, hair and nails) in man and animals by keratinophilic fungi (dermatophytes) results in dermatophytosis (also known as tinea or ringworm). As conventional laboratory procedures for the identification of dermatophytes are either slow or lack specificity, improved diagnostic methods are required. The application of nucleic acid amplification technology has made rapid and precise identification of dermatophytes possible. Recent studies have shown that when one of the four random primers (OPAA11, OPD18, OPAA17 and OPU15) was used in arbitrarily primed PCR (AP-PCR), up to 20 of the 25 dermatophyte species or subspecies under investigation could be distinguished on the basis of characteristic band patterns detected in agarose gel electrophoresis. A combination of two random primers (OPD18 and OPAA17) used in separate reaction tubes identified 23 of the 25 dermatophyte species or subspecies examined. AP-PCR provides a rapid and practical tool for identification of dermatophyte isolates that is independent of morphological and biochemical characteristics and thus enhances laboratory diagnosis of dermatophytosis.

Animals↗
PubMed2006

Farmworker exposure to pesticides: methodologic issues for the collection of comparable data.

The exposure of migrant and seasonal farmworkers and their families to agricultural and residential pesticides is a continuing public health concern. Pesticide exposure research has been spurred on by the development of sensitive and reliable laboratory techniques that allow the detection of minute amounts of pesticides or pesticide metabolites. The power of research on farmworker pesticide exposure has been limited because of variability in the collection of exposure data, the predictors of exposure considered, the laboratory procedures used in analyzing the exposure, and the measurement of exposure. The Farmworker Pesticide Exposure Comparable Data Conference assembled 25 scientists from diverse disciplinary and organizational backgrounds to develop methodologic consensus in four areas of farmworker pesticide exposure research: environmental exposure assessment, biomarkers, personal and occupational predictors of exposure, and health outcomes of exposure. In this introduction to this mini-monograph, first, we present the rationale for the conference and its organization. Second, we discuss some of the important challenges in conducting farmworker pesticide research, including the definition and size of the farmworker population, problems in communication and access, and the organization of agricultural work. Third, we summarize major findings from each of the conference's four foci-environmental exposure assessment, biomonitoring, predictors of exposure, and health outcomes of exposure-as well as important laboratory and statistical analysis issues that cross-cut the four foci.

Agriculture↗
PubMed1991

Tricalcium phosphate amino acid capsules as a drug delivery system for steroid hormones.

Several researchers have reported that there are drawbacks in using the current pharmacotherapeutic procedure for the treatment of endocrine insufficiency. Furthermore, such drugs have to be taken on a lifelong basis. Also, long term exposure to drugs seems to be necessary in the treatment of the most common endocrine disorders. Thus, the traditional routes of administration expose the body constantly to large fluctuating levels of drugs. This study presents a possible alternative route of administering the drugs for the treatment of the aforementioned cases. Ceramics, such as, tricalcium phosphate (TCP) have been used extensively in the dental and orthopedic fields. To date, the use of compressed TCP ceramic capsules as drug delivery systems has not been investigated. The objective of this study is to investigate the capability of calcined TCP amino acid-steroid matrix to deliver progesterone (P), in a sustained manner. Microcrystals of TCP were prepared by following standard laboratory procedures. Three different amino acids (cysteine, proline, and lysine) were incorporated (individually or in combination form) into the TCP matrix. Each matrix contained 100 mg of P and the homogeneous material was compressed at 5000 Kg compression load using a French Pressure Cell. The total amount of steroid released was monitored spectrophotometrically. The results of this study suggest that: (i) TCP- amino acid-steroid composites can be used to deliver steroids in a sustained manner. (ii) The amount of steroid released from the matrix system was found to be dependent upon the physiochemical characteristics of the amino acids.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed2002

Authentication of natural vanilla flavorings: isotopic characterization using degradation of vanillin into guaiacol.

The isotopic investigation of vanillin has been extended to the new sources of natural precursors of vanillin recently introduced with a view of obtaining natural vanillin by biotechnological processes. To check the consistency of the isotopic composition of vanillin with that of the corresponding aromatic fragment, a selective degradation reaction into guaiacol was carried out. The reaction was shown to proceed without significant isotopic fractionation at the sites of interest, and an optimized procedure was defined from the results of an experimental design involving the quantity of reagent and the temperature and duration of the experiment. Guaiacol, which can be easily obtained in a reasonable time, is an interesting isotopic probe for carbon- and oxygen-isotope ratio mass spectrometry (IRMS) determinations. It provides (13)C information specific to the aromatic fragment and, combined with delta(13)C values measured on vanillin itself, it improves the authentication potential of carbon-IRMS. Thus, the natural status of ferulic acid may be characterized by significant (13)C depletion at the formyl site. Similarly, the oxygen-18 content of guaiacol is a better authentication tool than delta(18)O of vanillin because it does not suffer the drawback of being altered by chemical exchange of the sp(2) oxygen atom with water in industrial or laboratory procedures. Although collaborative studies are still necessary to improve the interlaboratory reproducibility of the delta(18)O parameters, consistent results can be obtained in an intralaboratory context. It is shown in particular that chemical oxidation of ferulic acid is characterized by a relative enrichment of the aromatic moiety of vanillin.

Benzaldehydes↗
PubMed2003

Effects of training on stress-related behavior of the common marmoset (Callithrix jacchus) in relation to coping with routine husbandry procedures.

Using positive reinforcement, J. McKinley trained 12 common marmosets (Callithrix jacchus) to provide urine samples on request. The study then exposed the marmosets to mildly stressful, routine husbandry procedures (i.e., capture and weighing). The nonhuman animals spent less time inactive poststressor as opposed to prestressor. L. Bassett collected matched behavioral data from 12 nontrained marmosets who were less accustomed to human interaction. These animals spent significantly more time self-scratching and locomoting as well as less time inactive, poststressor. Collapsed data from the 2 populations showed increased scent marking, poststressor. These results suggest that locomotion, self-scratching, and scent marking are useful, noninvasive behavioral measures of stress and, thus, reduced welfare in the common marmoset. Overall, nontrained animals showed more self-scratching than did their trained counterparts. It was not possible to collect urine from nontrained marmosets. In response to the stressor, however, trained animals showed no significant change in excreted urinary cortisol. These results suggest that training marmosets may allow them to cope better with routine laboratory procedures.

Animal Husbandry↗
PubMed1997

The clinical usefulness of glucated haemoglobin in diabetes care evaluated by use of a medical technology assessment strategy.

With the introduction of measurements of glycated haemoglobin in a single blood sample as an index of long-term blood glucose control, the clinically usefulness of these measurements was questioned. The aim of this study was to evaluate measurements of glycated haemoglobin as a new test for metabolic regulation in diabetes management by use of a medical technology assessment strategy. Technology assessment in medicine has been defined as "the art and science of evaluating medical practices", but the strategy has to be adjusted to the medical technology in question always including the following three stages: (a) problem definition and identification of medical technology, (b) analysis by testing the technology with consideration to its benefit and harm, its costs, and its social consequences, and (c) synthesis of the accumulated knowledge about the technology. Based on the out-put from the problem definition we found it necessary to investigate some of the identified problems ourselves before implementation of routine measurements of glycated haemoglobin. Several studies were accomplished to validate the laboratory technology in terms of analytical reliability and its clinical usefulness. We wanted to (1) define goals of analytical quality of assays of glycated haemoglobin based on clinical goals, (2) establish a laboratory method for measurements of glycated haemoglobin fulfilling the defined goals, (3) investigate the ability of measurements of glycated haemoglobin to characterize impaired glucose tolerance, (4) evaluate the clinical usefulness of measurements of glycated haemoglobin in the assessment of metabolic regulation in non-insulin-dependent diabetes mellitus (NIDDM), (5) compare physicians' assessment of metabolic control in insulin-dependent diabetes mellitus (IDDM) with measurements of glycated haemoglobin and determine whether knowledge of glycated haemoglobin values would result in improved metabolic control, and (6) evaluate the organizational and economical consequences of introducing regular measurements of glycated haemoglobin. The analysis required a multi-disciplinary approach. Based on our own studies and the available data information we found that measurements of glycated haemoglobin should be regarded the most clinically appropriate test of long-term glycemia and should be introduced into routine management of adult patients with IDDM and NIDDM with the following guidelines concerning methodologies, clinical utility, organizational consequences. The individual laboratory has to establish and secure its own method since at present we are still without an internationally accepted reference method or reference material. The method should measure HbA1c without measuring the labile intermediate pre-HbA1c and provide separate detection of haemoglobin variants. We investigated the analytical goals for the performance characteristics of assays based on biological variation and on the clinical significance of a certain change in concentrations in the individual. Different strategies lead to different analytical goals of CVA between 2-4%. An oral glucose tolerance test is still required to establish the diagnosis of diabetes. Measurements of glycated haemoglobin have been suggested as an alternative but a considerable overlap between the WHO-defined groups of normal and impaired glucose tolerance was observed. In patients with IDDM our studies demonstrated the limitations of traditional clinical judgement and the laboratory procedures in providing an accurate assessment of blood glucose control and that knowledge of HbA1c values allowed the clinician to identify patients in poor glycemic control and lead to improvement in glycemic control. In patients with NIDDM our study showed that measurements of HbA1c provided information that was otherwise not obtainable in the usual clinical setting in primary health care. Measurements of glycated haemoglobin were easily accepted by patients with diabetes. (ABSTRACT TRUNCA

Adult↗
PubMed1997

Significance of pulpal pressure during clinical bonding procedures.

PURPOSE: To determine whether pulpal pressure in vital teeth plays a significant role in dentin bonding procedures. MATERIALS AND METHODS: Half the teeth in three baboons received root canal treatment thus eliminating pulpal pressure. All teeth were then prepared on the buccal surface with a diamond wheel to create flat surfaces into dentin, measuring at least 4 mm in diameter. Dentin bonding systems from two manufacturers were applied. Using a Bencor tensile nozzle freehand, 3.5 mm diameter composite buttons were bonded to the prepared surfaces. The animals were sacrificed 24 hours later, the teeth removed and mounted in specimen rings, using the same Bencor tensile nozzle for proper axial alignment. The composite buttons were tested for shear bond strength in a tensometer. RESULTS: The results showed no statistically significant difference between the two materials tested, furthermore there was no difference in SBS between materials bonded to vital or non-vital teeth. After completion of the tests, 20 teeth (10 for each dentin bonding system) were prepared according to standard laboratory procedures for a dentin bond strength test using the Bencor Multi-T system. The values obtained were higher, but again there was no statistically significant difference between the two systems.

Animals↗
PubMed2005

Mechanistic implications for the use and monitoring of recombinant activated factor VII in trauma.

As interest in the use of activated recombinant factor VII (rFVIIa) in trauma grows, questions arise regarding how best to monitor rFVIIa therapy and when rFVIIa may be expected to improve hemostasis. Knowledge of the mechanisms of action may be combined with available data on laboratory monitoring and efficacy in various coagulopathic states in coming to clinically relevant conclusions. This review addresses the physiology of hemostasis, placing emphasis on how rFVIIa influences the process by both tissue factor dependent and tissue factor independent mechanisms. This is extended to a mechanistic consideration of how rFVIIa may function under acidotic, hypothermic, and hemodilutional and/or consumptive conditions of trauma related coagulopathy. When these considerations are viewed alongside the available clinical data, it becomes apparent that rFVIIa has potential to improve hemostasis during trauma coagulopathy, within limitations. Common laboratory procedures are discussed with reference to mechanisms of action of rFVIIa and the available clinical data. Although there is no single assay that can predict rFVIIa efficacy in trauma, the prothrombin time (PT) is recommended as a minimum. Although a shortened PT does not predict success, correction of PT into the normal range may be a better indicator. A nonresponding PT appears to indicate that rFVIIa alone will not lead to hemostasis, and that additional blood products and other measures must be applied. Once the patient is more stable, PT and thromboelastography are recommended.

Blood Coagulation↗
PubMed1994

[Application of gene technology to clinical pathology].

Recently striking progress has been made in molecular biology. Among the newly developed techniques, PCR (polymerase chain reaction) is making an epoch in DNA diagnosis in the field of clinical pathology and laboratory medicine. In this symposium, we discussed the available PCR methods in DNA diagnosis and also the future prospect of PCR method as a routine laboratory procedure. First, Dr. Kawabata reviewed the PCR technique and analytical procedures of PCR products. Next five symposium presented the data on DNA diagnosis for particular diseases using the PCR method. Dr. Hasebe presented the HCV genotyping data from the patients. Dr. Hirose showed us the difference in accuracy in DNA typing of Chlamydia trachomatis antigen between the DNA probe method and PCR method. He also introduced the newly developed LCR method. Dr. Kondo reviewed the methods of DNA diagnosis for malignant lymphoma. Dr. Yaginuma presented the analyzed data of tumor suppressor gene p53 in some gynecological tumors. Dr. Azuma presented a case of chronic granulomatosis with a point mutation on the gp91-phox gene which had been revealed by RT-PCR. Next Dr. Yagihashi introduced the protocol for DNA typing of the HLA class II. Finally, Dr. Tanaka presented the availability of the PCR method for the convalescent screening of bone marrow transplantation. We hope this symposium is fruitful and motivating for all staffs of laboratory medicine and pathology. In closing my remarks, I express our appreciation to all symposists as well as Prof. Hisami Ikeda, president of the 27th general meeting of the Hokkaido branch, the Society of Clinical Pathology, planned this symposium.

Genetic Techniques↗
PubMed1992

Evaluation of the use of the reflectance meter by several operators in field screening for diabetes mellitus.

The performance of reflectance meters for measuring blood glucose concentrations was evaluated in other studies previously and was found to be satisfactory. In the present study, we have evaluated the reliability of one brand of such meters (Glucometer II), when used by several operators, for blood glucose measurements during an epidemiological survey. We have compared the results obtained by the meter with those obtained by a standard hospital laboratory procedure for the same samples. A high and statistically significant degree of correlation (r = 0.901) was observed between the two groups of measurements. The linear regression equation was Y = 0.9X + 13.4. We conclude that the Glucometer II is an accurate and practical instrument even when used by several operators in epidemiological surveys provided that adequate training is given to those operators prior to using the instrument. This is important since the use of reflectance meters in epidemiological surveys is becoming increasingly widespread especially in the third world countries.

Adult↗
PubMed1993

Infrequent shedding and transmission of herpesvirus simiae from seropositive macaques.

The epizootiologic properties of Herpesvirus simiae (B virus) were studied in singly housed macaques (Macaca mulatta and M. fascicularis) in a biomedical vivarium to determine whether commonly encountered environments and procedures such as quarantine, breeding, Caesarean section, parturition, and social stress induced virus shedding and transmission. Macaques were tested serologically and for infectious virus. Oral, conjunctival, and vaginal swab samples were obtained repeatedly. Virus excretion was not detected during a 7-week quarantine of 32 newly acquired, singly housed animals tested every other week for 6 weeks, and none of 19 seronegative animals from this group seroconverted during 7 weeks in quarantine. No virus shedding was detected in 16 seropositive animals tested weekly for 3 weeks after Caesarean section or normal parturition or in 11 seropositive animals following introduction of new males to animals rooms. One animal seroconverted after repeated breeding of seropositive animals to seronegative partners. Fifty-three singly housed offspring remained seronegative for up to 10 years, even if born to seropositive dams, and only 1 of 86 singly housed animals less than 7 years old was seropositive. These results suggest that shedding of B virus from seropositive macaques is uncommon, when subjected to common laboratory procedures or environments, and that transmission is rare in singly housed animals. These results may be useful in establishing B virus-free colonies of macaques.

Animals↗