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At least 343 records · Page 19Linked to original sources

Myofacial pain dysfunction: analysis of 476 patients.

Myofacial Pain Dysfunction (MPD) is a musculoskeletal dysfunction involving malrelationship among the neuromuscular system, temporomandibular joints, and dental occlusion. The illness affects children and adults of all ages and both sexes. Patients complain of pain and/or dysfunction in the mandible, temporomandibular joints, ears, oral cavity, head, and neck. Electronic measurement of mandibular movement and associated muscle function now provide reproducible data with which the parameters of this illness and therapy can be designed and monitored. In this study, data are presented on 476 MPD patients. Included are statistics on the most commonly occurring symptoms, clinical examination findings, and electronic test data before and following treatment. The mandibular kinesiograph (MKG) is used to track mandibular movement and compare the natural dental occlusal position and a neuromuscularly balanced position of occlusion. Electromyography (EMG) is used to analyze the resting status of mandibular muscles and the functioning in the occlusal position. The data show a positive correlation between the clinical symptoms of MPD and unhealthy mandibular position at occlusion, accompanied by specific unhealthy muscle activity. There is a strong positive correlation between a therapeutic change in the dental occlusion to a neuromuscularly healthy position using a precision orthotic appliance and the relief of symptoms within 1 month as expressed by 88% of the patients. A similar correlation exists at 3 months and long-term.

Adolescent↗

Monitoring human exposure to urban air pollutants.

A multidisciplinary study on a general population exposed to vehicle exhaust was undertaken in Pisa in 1991. Environmental factors such as air pollution and those associated with lifestyle were studied. Meanwhile, biological and medical indicators of health condition were investigated. Chromosomal aberrations, sister chromatid exchanges (SCEs), and micronuclei in lymphocytes were included for the assessment of the genotoxic risk. Because of the large number (3800) of subjects being investigated, standardization of protocols was compulsory. The results on data reproducibility are reported. To assess the reliability of the protocol on a large scale, the population of Porto Tolle, a village located in northeast Italy, was studied and compared to a subset of the Pisa population. Preliminary results showed that probable differences between the two populations and individuals were present in terms of SCE frequencies. The study was potentially able to detect the effects of several factors such as age, smoking, genetics, and environment. The in vitro treatment of lymphocytes with diepoxybutane confirmed the presence of more responsive individuals and permitted us to investigate the genetic predisposition to genetic damage. The possible influence of environmental factors was studied by correlation analyses with external exposure to air pollutants as well as with several lifestyle factors.

Adolescent↗

Latex immunoturbidimetric assay for soluble fibrin complex.

BACKGROUND: Soluble fibrin complex (SFC), composed of fibrin monomer and fibrinogen derivatives, is known to exist in the circulating blood in patients with thrombosis. Its detection and quantification are useful for obtaining information about the condition and degree of intravascular coagulation in early-stage thrombosis, but there is no rapid method to measure SFC in plasma for clinical use. METHODS: We obtained a monoclonal antibody that specifically reacts with SFC, with desAA-fibrin as the immunogen, and developed a rapid and sensitive latex immunoturbidimetric assay (LIA) using latex-immobilized anti-SFC monoclonal antibody. The assay system was based on the increase in turbidity induced by the reaction of the latex-immobilized anti-SFC monoclonal antibody with SFC in plasma, and the assay procedure was fully automated on a Hitachi 911 analyzer. RESULTS: The method had an analytical range of 3-300 mg/L. Intra- and interassay precision studies indicated that this system provided reproducible data (CVs <3.0% and <2.0%, respectively). The assay detection limit was <0.5 mg/L. There was no interference from bilirubin (up to 440 mg/L), hemoglobin (up to 9.6 g/L), Intralipid (up to 10%), D-dimer (up to 200 mg/L), and rheumatoid factor (up to 470 000 IU/L). SFC concentrations in plasma from patients with thrombotic diseases [mean (SD), 48.9 (57.6) mg/L; n = 160) were significantly higher than those in plasma from healthy individuals [1.8 (2.1) mg/L; P <0.001; n = 304]. CONCLUSION: In terms of linearity, precision, and sensitivity, the LIA, performed on a Hitachi 911 automated analyzer, may be useful for measurement of SFC in plasma.

Antibodies, Monoclonal↗

Interaction of p53 with cellular proteins.

Cellular proteins that interact with p53 play a major role in both positive and negative regulation of this tumor suppressor and can fine-tune its response to specific cellular stresses. As a consequence, p53 biology will not be complete until these interacting proteins are fully characterized. This chapter outlines two methods for identifying and characterizing p53-binding proteins: (i) glutathione-S-transferase (GST) protein-protein interaction assay; and (ii) co-immunoprecipitation (co-IP) assay. These two methods are ideal for any laboratory to perform; the assays are short in duration, do not require specialized expertise to establish in the laboratory, give reliable and reproducible data, and are cost-efficient, because few reagents are needed. This chapter gives a basic description of these two techniques and provides tips that are not found in other protocol manuals on how to achieve the best results.

Animals↗

Analysis and screening of yeast artificial chromosome libraries by filter hybridization.

Large-scale genome mapping and sequencing projects nowadays rely on robotic systems for yeast artificial chromosome (YAC) library processing, handling, and analysis. The advantages are obvious. Robots are fast, less labor intense, and the data reproducibility is high. However, there may be cases in which automated systems are not available or are unnecessary, for example, if the YAC library is small. In this chapter, we describe a simple method to process YAC libraries manually and screen them by conventional filter hybridization.

Chromosomes, Artificial, Yeast↗

A new technique for the quantitative analysis of cranial suture biology.

OBJECTIVE: Our objective was to assess the ability of the microcomputed tomography scanner to correctly image normal and synostosed cranial sutures at the ultrastructural level. DESIGN AND METHODS: Two specimens of coronal sutures were collected from operative specimens. After appropriate preparation, histological sections were obtained and stained with toluene blue for evaluation. Representative histological sections were compared to microcomputed tomography slices. RESULTS AND CONCLUSIONS: With microcomputed tomography, we successfully imaged one normal and one synostosed human coronal suture and performed a quantitative analysis of these specimens. Microcomputed tomography scanning was found to be a highly accurate imaging device for the evaluation of cranial suture development. Microcomputed tomography offers three-dimensional imaging at the microscopic level and allows for rapid quantitative analysis of bone architecture, including several measurements unavailable through histologic analysis. We believe that microcomputed tomography can play an important role in imaging and in the quantitative analysis of the stereology of bone microarchitecture. Among its advantages, microcomputed tomography is able to image many more slices than are obtainable through histology, and the method is not prone to human error. Microcomputed tomography slices are generated without destruction of the specimen and without loss or corruption of reproducible data. Structure-oriented slices from microcomputed tomography together with cellular-oriented sections from histology are complementary in the overall quantitative analysis of cranial sutures.

Child, Preschool↗

A method to measure pain associated with hypersensitive dentin.

Pain associated with dental hypersensitivity has been difficult to assess. An electronic threshold measure was developed to increase the degree of objectivity in a subject's response to a cold thermal stimulus. The apparatus consisted of a miniature thermistor connected to a medical multichannel recorder with a hand-held event recorder. The thermistor was placed adjacent to the hypersensitive area for an accurate temperature measure of the point at which the subject first reported pain. Room temperature air was gently blown on the hypersensitive area, dropping the surface temperature evenly from intraoral temperature to room temperature. Results indicated that this method of assessment provided consistent and reproducible data. The apparatus can detect changes in sensitivity and offers an objective approach to sensitivity studies.

Dentin Sensitivity↗

Practical considerations in the testing of VO2max in runners.

Maximal oxygen intake (VO2max) may be the most physiologically significant and, therefore, the most commonly measured parameter in the physiological assessment of well trained runners. To insure valid and reliable VO2max values, there are a number of practical concerns that must be addressed. An exercise modality must be selected that activates the specific muscle mass and duplicates the motion utilised in the runners' training programme. Motorized treadmill running has been shown to allow the most efficient, valid and reproducible VO2max values in a controlled testing environment. A testing protocol must be used that is easily administered, comfortable for the runner, allows test completion within 10 minutes, uses grade increments at a constant speed, and is reproducible. Speeds should be selected that approximate the runner's training pace. The criterion for the attainment of VO2max include the levelling off of VO2 with an increase in work stage, the onset of extreme exhaustion, the respiratory exchange ratio exceeding 1.1, blood lactate levels approaching or exceeding 10 mmol/L, and ratings of perceived exertion of 19 or 20. Quality control in terms of standardisation of procedures and calibration and maintenance of equipment is essential for the minimisation of technological error. Measurement equipment must be affordable, dependable, easily calibrated, yield reproducible data, and be within the technical skill levels of the operating personnel.

Exercise Test↗

The molecular genetics of schizophrenia.

Until recently, schizophrenia has proven refractory to molecular genetic investigation, with all advances being hastily followed by retreat. However, more realistic interpretations of old study designs, combined with newer forms of investigation appear at last to be generating reproducible data, suggesting that the field is finally making sustained progress. In this review, we discuss the rationale behind the approaches now in widest application and discuss the results of recent linkage and association studies of schizophrenia. We conclude that, because of advances in the methodology of molecular genetics and improvements in study design, there are solid grounds for believing that susceptibility genes for schizophrenia will be identified in the foreseeable future.

Humans↗

Multiple biomarkers of colorectal tumor in a differential diagnosis model: a quantitative study.

AIM: To evaluate the multiple biomarkers of colorectal tumor and their potential usage in early diagnosis of colorectal cancers. METHODS: Multiple biomarkers (DNA contents, AgNOR, PCNA, p53, c-erbB-2) in 10 normal colorectal mucosae, 37 colorectal adenomas and 55 colorectal cancers were analyzed quantitatively in the computed processing imaging system. Discrimination patterns were employed to evaluate the significance of single and multiple indices in diagnosis of colorectal cancers. RESULTS: The mean values of the analyzed parameters increased in order of the normal mucosa, adenoma and adenocarcinoma, and this tendency reflected the progression of colorectal malignancy. The parameters including DNA index, positive rates, densities of AgNOR, c-erbB-2, and p53, shape and density of nucleus were relatively valuable for diagnoses. Then a diagnostic discrimination model was established. The samples were confirmed with the model, the sensitivity rates in cancer group and adenoma group were 96.36% and 89.19%, respectively. The value of proliferating cell nuclear antigen (PCNA) in early diagnosis of colorectal cancers was uncertain. CONCLUSION: The quantitative evaluation of some parameters for colorectal tumor can provide reproducible data for differential diagnosis. The established diagnostic discrimination model may be of clinicopathological value, and can make the early diagnosis of colorectal cancer possible.

Adenoma↗

[Submicroscopic structure of collagen--a basis for the interpretation of corresponding polarization-optical and histochemical findings].

In view of new possibilities of acquiring relatively quantitative information about the molecular structure of collagenous fibres in histological section with the help of polarization and histochemical methods a survey is given of the most important aspects of the molecular structure of collagen in connection with the formation of "cross-links", giving due attention to the role of functional groups. These create the basis for interpreting morphological findings covering free amino-groups of lysin and hydroxylysin, guanidine groups of arginine and carboxyl groups of glutamic acid and asparaginic acid, gained by adding phenol or toluidine blue to collagenous fibres and by performing path difference measurements. References made to the applicability of this polarization-histochemical method in clinical research and diagnostics, in gathering reproducible data on processes of development or growth and aging and pathological changes in collagen are intended to encourage wide use of this examination technique in practice.

Age Factors↗

[Ultrasonic doppler technique in angiology (author's transl)].

The ultrasonic Doppler technique is a simple, non-stressing and harmless method of angiological investigation requiring little time. Today it is considered to be the best-suited procedure among the non-invasive instrumental methods in angiological diagnosis. It provides well reproducible data with regard to peripheral arterial blood flow and highly valuable information on functional conditions in the area of carotid flow and in the iliofemoral venous system. This method can be recommended unreservedly for use in general practice as well.

Arterial Occlusive Diseases↗

Novel functional multiparameter flow cytometric assay to characterize proliferation in skin.

Keratins are a group of cytoskeletal proteins that are found in human epidermis and other stratified squamous epithelia. Several different types of keratins have been described. Keratin 10 (K10) is a keratin that is expressed in well differentiated, suprabasal keratinocytes, and keratin 6 (K6) is a keratin which is associated with hyperproliferation. Psoriasis is a chronic inflammatory skin disease, and besides inflammation, disturbed differentiation and hyperproliferation are its hallmarks. In order to study the hyperproliferation associated keratinization in both well differentiated and poorly differentiated keratinocytes, and in order to assess the proliferative activity of all K10 and K6 subpopulations, simultaneous assessment of K6, K10, and DNA content is required. So far, a triple staining protocol had not been available. In the present study, we established a novel protocol for simultaneous measurement of K6, K10, and DNA content, which enables the characterization of the proliferative activity of several cellular subpopulations in epidermis. From 16 patients with psoriasis and from 15 healthy volunteers, punch biopsies were obtained. After preparation of single cell suspensions, cells were stained with the anti-keratin 10 IgG(1)-isotype monoclonal antibody RKSE60, with the anti-keratin 6 IgG(2a)-isotype monoclonal antibody LHK6B, and with the DNA fluorochrome TO-PRO-3 iodide. Isotype specific secondary antibodies conjugated with phycoerythrein (PE) and fluorescein isothiocyanate (FITC) were used as the second step in the staining procedure. Controls were measured omitting the primary antibodies, and gates were set in order to differentiate between the K10 and K6 subpopulations. Samples from both psoriatic patients and healthy volunteers were than measured. Owing to the IgG specificity of RKSE60 and LHK6B, no cross-reactivity was observed between these antibodies. The triple staining with RKSE60, LHK6B, and TO-PRO-3 iodide showed subpopulations of K10 expressing cells, K10/K6 co-expressing cells, and K6 only expressing cells. There was a significant difference in the proportion of K6 expression and K10/K6 co-expression between psoriatic and normal skin. Moreover, the proliferative activity of these subpopulations could be quantified by this protocol. We concluded that a triple staining protocol for the assessment of K6, K10, and DNA content, using the monoclonal antibodies LHK6B, RKSE60, and TO-PRO-3 iodide, supplies reliable and reproducible data for cellular studies on these keratins and for studying the proliferative activity of the subpopulations of these keratins in epidermis. Moreover, the present study showed that with respect to the proportion of K6, significant differences are present between psoriatic and healthy human skin.

Adult↗

[Potency Testing of Erysipelas Vaccines in Mice. ELISA vs. Challenge]

Vaccines are widely used for the prophylaxis of swine erysipelas. According to national pharmacopoiea requirements, potency of these biologicals has to be tested in a mouse challenge model. Many animals are needed and the test causes much suffering. The development of an enzyme linked immunosorbet assay (ELISA) using an alkaline extract of Erysipelothrix rhusiopathiae as antigen for coating the microtitre plate allows us to measure antibody titres in the serum of vaccinated mice. By comparing the antibody titres of vaccinated mice with the results of the animal challenge model it could be demonstrated that the in vitro method gives reliable and reproducible data which correlate with the results of the in vivo model. The ELISA offers the possibility to refine the currently used animal test, by replacing the challenge procedure and reducing the number of animals.

Journal Article↗

A comparative study of fish species identification by gel isoelectrofocusing two-dimensional gel electrophoresis, and capillary zone electrophoresis.

A comparative study of fish species identification was accomplished using three different electrophoretic techniques. Sarcoplasmic proteins were extracted from three related fish species and subjected to gel isoelectrofocusing (IEF), two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), and capillary zone electrophoresis (CZE). The fish species--Genypterus chilensis, Genypterus blacodes, and Genypterus maculatus--were from the Ophidiidae family. The three electrophoretic techniques provided suitable fish species identification. Nevertheless, CZE demonstrated several advantages over the other two conventional techniques. Some of the benefits include the use of small amounts of reagents; short separation times, permitting fast comparative analysis; data reproducibility; and ease with which the technique is performed.

Animals↗

Development of a microculture system for stimulation of chicken peripheral blood lymphocytes with concanavalin A.

A microculture system in conjunction with a semiautomatic multiple sample harvester (SAMSH) was used to study the in vitro properties of chicken peripheral lymphocytes. This new procedure enabled doing rapid multiple tests, using relatively few cells, and was highly reproducible. Data were presented to show many variables that are involved in studying the concanavalin A (Con A) response of chicken lymphocytes in a microculture system. Analysis indicated that the conditions for optimal Con A stimulation as measured by incorporation of 3H-TdR include: (a) use of 2 x 10(6) cells per culture in RPMI 1640 culture medium in the absence of any serum, (b) use of 0.4 mug of Con A per culture, (c) incubation at 37 degrees C for 72 hours, and (d) addition of 1 muCi of 3H-TdR to each culture 12 to 24 hours prior to termination. This technique could be used to monitor immunocompetence of the chicken.

Animals↗

[New functional cerebral cartography: studies of plasticity of the human brain].

The non-invasive brain scanning techniques, introduced a quarter of a century ago, have become crucial for diagnosis in clinical neurology. They have also been used to investigate brain function and have provided information about normal activity and pathogenesis. They have been used to investigate functional specialisation in the brain and how specialised areas communicate to generate complex integrated functions such as speech, memory, the emotions and so on. Brain plasticity is a generic term that has now come to be used to signify any changes in brain structure or function. The phenomenon is poorly understood, and yet clinical neurologists are aware that spontaneous recovery from brain lesions is not uncommon. An improved understanding of the mechanisms of recovery may generate new therapeutic strategies and indicate ways of modulating mechanisms that promote plastic compensation for loss of function. The main methods used to investigate these issues are positron emission tomography and magnetic resonance imaging (MRI). The techniques of functional brain mapping and computational morphometrics depend on high performance scanners and a validated set of analytic statistical procedures that generate reproducible data and meaningful inferences from them. The motor system presents a good paradigm to illustrate advances made by scanning towards an understanding of plasticity at the level of brain areas. The normal motor system is organised in a nested hierarchy. Recovery from paralysis caused by internal capsule strokes involves functional reorganisation manifesting as changed patterns of activity in the component brain areas of the normal motor system. The pattern of plastic modification depends in part on patterns of residual or disturbed connectivity after brain injury. Therapeutic manipulations in patients with Parkinson's disease using deep brain stimulation, dopaminergic agents or foetal mesencephalic transplantation provide a means to examine mechanisms underpinning plastic change. Other models of plastic change, such as normal visuospatial learning or re-establishing speech comprehension after cochlear implantation in the deaf illustrate how patterns of brain function adapt over time. Limitations of the scanning techniques and prospects for the future are discussed in relation to new developments in the neuroimaging field.

Brain↗

Factors affecting oogenesis in the South African clawed frog (Xenopus laevis).

Xenopus laevis, commonly known as the South African Clawed frog, is a hardy adaptable species that is relatively easy to maintain as a laboratory animal. Gametogenesis in wild Xenopus laevis is continuous and under ideal conditions, reproduction can occur year round. This unique aspect of amphibian reproduction offers an advantage over mammalian model systems: the eggs and oocytes collected from laboratory maintained Xenopus laevis provide an abundant and readily obtainable supply of material for cellular and biological research. However, many investigators report that laboratory Xenopus laevis go through periods of unexplained inefficient or complete failure of oocyte production or the production of poor quality oocytes. This results in experimental delays, inability to reproduce data, and ultimately the use of more animals. There is a lack of evidenced based information regarding the housing conditions that are necessary to optimize the health and fecundity of this species in captivity, but studies of wild Xenopus laevis have shown that temperature, age of the female, and nutrition are of key importance. The objective of this report is to review oogenesis with a special emphasis on these factors as they pertain to laboratory Xenopus laevis maintained for the purpose of providing a steady supply of eggs and oocytes. Harvesting methods and other experimental techniques that affect the quality of eggs and oocytes are also discussed.

Animals↗