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PubMed1994

Temperature changes during therapeutic ultrasound in the precooled human gastrocnemius muscle.

Therapeutic ultrasound is frequently employed as a deep heating rehabilitation modality. It is administered in one of three ways: a) ultrasound with no preceding treatment, b) ultrasound on preheated tissues, or c) ultrasound on precooled tissues. The purpose of this study was to investigate the effect of ultrasound treatments on the tissue temperature rise of precooled human gastrocnemius muscle. Sixteen male subjects had a 23-gauge hypodermic needle microprobe inserted 3 cm deep into the medial aspect of their anesthetized gastrocnemius muscles. Data were gathered on each subject for one of two randomly assigned treatments: a) ultrasound treatment on precooled tissue, or b) ultrasound with no preceding treatment. Each treatment consisted of ultrasound delivered topically at 1.5 watts/cm(2) in a continuous mode for 10 minutes. Ultrasound was applied in an overlapping longitudinal motion at 4 cm/s, with temperature readings recorded at 30-second intervals. We discovered a difference between the two treatment methods [t(14) = 16.26, p < .0001]. Ultrasound alone increased tissue temperature an average of 2 degrees C, whereas ultrasound preceded by 15 minutes of ice did not increase tissue temperature even to the original baseline level. We concluded that, at a depth of 3 cm, ultrasound alone provided a greater heating effect than ultrasound preceded by an ice treatment.

Journal Article↗

PubMed1995

High dose rate brachytherapy for prevention of restenosis after percutaneous transluminal coronary angioplasty: preliminary dosimetric tests of a new source presentation.

PURPOSE: Balloon dilatation of coronary artery stenosis has become a standard treatment of atherosclerotic heart disease. Restenosis due to excessive intimal cell proliferation, which subsequently occurs in 20-50% of patients, represents one of the major clinical problems in contemporary cardiology, and no satisfactory method for its prevention has thus far been found. Because modest doses of radiation have proved effective in preventing certain types of abnormal cellular proliferation resulting from surgical trauma, and brachytherapy has already been used successfully after dilation of peripheral arteries, development of a radioactive source suitable for coronary artery applications would be of great interest. METHODS AND MATERIALS: Nonradioactive flexible yttrium-89 wires (diameter of 0.15 and 0.26 mm) were activated within the thermal neutron flux of an experimental reactor. Standard angioplasty balloons (2 cm long, 2.5 mm in diameter when inflated) were inserted for dosimetry into a specially manufactured tissue equivalent phantom. Four wells, drilled perpendicular to the axis of the balloon, allowed for the insertion of thermal luminescent dosimeters (TLDs; 2 mm of diameter) and spacers. The angioplasty balloon was inflated with air or with contrast media. Radioactive yttrium-90 wires were left in the central lumen of the balloon for 2 min. Doses at the surface of the balloon, and at 1, 2, and 3 mm were determined from TLD readings. RESULTS: Doses obtained at the surface of the balloon, for a 2-min exposure for the 0.26 mm wire (balloon inflated with air) and the 0.15 mm wire (air or contrast), were 56.5 Gy, 17.8 Gy, 5.4 Gy, respectively. As expected for a beta emitter, the fall-off in dose as a function of depth was rapid. External irradiation from the beta source was negligible. CONCLUSIONS: Our experiments indicate that the dose rates attainable at the surface of the angioplasty balloon using this technique allow the doses necessary for the inhibition of intimal cell proliferation to be reached within a relatively short period of time. The thin yttrium-90 wires are very easy to handle, and their mechanical and radioactive properties are well suited to the requirements of the catheterization procedure.

Angioplasty, Balloon, Coronary↗

PubMed1999

Physical therapy for the equine back.

Before a physical therapy and rehabilitation program is suggested, the end requirement must be considered. All physiotherapeutic machines are subject to laboratory screening. In the United States, the approval of the Food and Drug Administration is required; in the United Kingdom, certification by the National Physics Laboratory has been required by law since January 1996. Laboratory experiments are continually conducted to examine and evaluate the effects on tissues of varied electrical waveforms, low-intensity electrical currents, sound waves, and light rays delivered by a variety of therapeutic apparatuses. It is interesting to note that the tissues used for this work are derived from the rabbit, rat, and chick embryo. If these investigative procedures demonstrate benefit to tissue behavior following trauma in laboratory animals, they are then considered to be of benefit to humans. Surely, it must follow that equal benefit is to be derived by other species with similar tissues. Despite veterinarian prejudice to the contrary and by careful case selection rather than random application, horses can profit from the application of electrotherapy and derive benefit from rehabilitation; thus, an informed physical therapist should be considered a useful member of a "care" team. Because no two cases are ever the same, it is impossible to write a "recipe" book stating exactly the dosage, treatment time, or applications per week or per day. Success depends on an in-depth assessment of individual needs followed by an informed choice of therapy. In the case of physical therapy, this necessitates the use of the appropriate modality at the appropriate time, always taking into account the fact that tissue is living and is therefore in a continually changing state. The art of the physical therapist is to read the situation each time a patient is seen and to proceed according to the findings of the moment. The author regrets that there are no double-blind trials to quote or published research available to substantiate rehabilitation methods. The therapy principles relating to proprioceptive input, cortical re-education, muscle recoordination, and atrophy following both micro- and macrotrauma have been transferred in field work from humans to horses.

Animals↗

PubMed2006

[Analysis of changes of anterior chamber depth after IOL implantation].

OBJECTIVE: To evaluate the changes of the anterior chamber depth (ACD) and the related factors after cataract surgery with IOL implantation in order to achieve the intended postoperative refraction. METHODS: Preoperative and postoperative ACD were examined in 117 patients (177 eyes) who underwent cataract surgery (phacoemulsification and posterior chamber IOL implantation). Correlations between changes of ACD and the axial lengths of the eyes, K-readings and IOL A-constants were assessed. Patients were followed-up for 3 to 24 months. RESULTS: (1) There was significant difference between preoperative ACD (3.19 +/- 0.39) mm and postoperative ACD (4.22 +/- 0.65) mm (P = 0.000). (2) The mean postoperative ACD change was (1.03 +/- 0.61) mm. The correlations between the ACD changes and the axial lengths of the eye and K-readings were statistically significant. (r = 0.866, r = 0.946, P = 0.001). (3) There was significant difference between preoperative ACD and postoperative ACD in the three different A-constants groups (118.9, 118.0 and 118.4) (P = 0.004, 0.001 and 0.001). There was significant difference between ACD changes in patients with A-constant 118.9 and that of 118.0 or 118.4 (P = 0.007, P = 0.01). There was no significant difference between ACD changes in patients with A-constant 118.0 and that of 118.4 (P = 0.957). CONCLUSION: Cataract surgery deepened anterior chambers at varying degrees, depending on the axial lengths of the eye, K-readings and the IOL A-constants. ACD changes and relevant factors should be considered in studying the accuracy of IOL refraction formula and in adjusting the calculated data.

Aged↗

PubMedDate not supplied

Association between bispectral analysis and level of conscious sedation of pediatric dental patients.

PURPOSE: This preliminary investigation evaluated the associations among multiple factors designed to measure depth of sedation, such as changes in the patient's electroencephalogram (EEG) via a bispectral analysis (BIS), other physiological variables, observed behaviors and clinical assessment of sedation levels consistent with the American Academy of Pediatric Dentistry (AAPD) sedation guidelines. METHODS: Thirty-four healthy pediatric patients between three to six years of age were enrolled in this institutionally approved study. All children required dental restorations and were uncooperative. The children received a routine oral sedation regimen used in our clinic consisting of chloral hydrate, meperidine, and hydroxyzine that varied in dose for each child. Intraoperatively, nitrous oxide/oxygen was also administered. Physiological variables including oxygen saturation, blood pressure and heart rate were recorded in compliance with AAPD sedation guidelines. The behavior and levels of sedation consistent with AAPD guidelines were also recorded. The BIS monitor was used to obtain EEG information. RESULTS: Useful data were recorded from 21 patients. The mean age and weight of the children were 46.1 +/- 10 months and 16.1 +/- 5 kgs, respectively. The results show a significant association between observed patient behavior and the AAPD levels of sedation (chi2 = 105.1, df = 6, P< 0.0001), between levels of sedation and behavior as a function of 12 time-oriented periods during treatment, (chi2=41.90, df=22, P<0.005 and chi2=48.0, df=33, P=0.04, respectively) and between BIS readings as a function of both level of sedation and behavior (chi2=105.1, df=6, P<0.001 and chi2=28.5, df = 18, P< 0.05, respectively). CONCLUSIONS: There appears to be a significant association between observed patient behaviors during sedation and levels of sedation as measured by BIS and AAPD sedation guidelines. The study also showed that, under treatment conditions used in this study, BIS does not appear to be a more valid means of monitoring sedation depth than the current commonly accepted methods.

Analysis of Variance↗

PubMed2005

Assessment of the anterior structures of eyes in a normal Northern Thai group using the Orbscan II.

OBJECTIVES: To evaluate the anterior structures of the eyes in normal Northern Thais include the corneal topography and thickness, as well as the anterior chamber depth (ACD) and the white-to-white (WTW) using the Orbscan II system. MATERIAL AND METHOD: One hundred and six eyes of 56 normal subjects were investigated using the Orbscan II. The simulated keratometry (SimK), astigmatism, corneal thickness, ACD and WTW were collected. The axial power maps as well as anterior and posterior elevation maps were read and categorized. Corneal thickness was measured in different regions and the pachymetry patterns were classified. RESULTS: The mean SimK was 44.18 (1.41)/43.30 (1.46) diopters (D) and the mean astigmatism was 0.93 (0.58) D. Symmetric bow tie was the most common axial power pattern in the anterior cornea (57.6%), followed by asymmetric bow tie (19.8%), irregular patterns (12.3%), round (9.4%), and oval (0.9%). Incomplete ridge (40.6%) and island (34%) were common elevation patterns observed in the anterior corneal surface, and island (92.5%) was the most common topographic pattern in the posterior. The thinnest point on the cornea had an average thickness of 512.49 (35) micron and was located at an average of 0.43 (0.24) mm from visual axis. In the pachymetry maps, round (47.2%) and oval (45.3%) were common patterns. The mean ACD and WTW was 2.79 (0.35) and 11.61 (0.36) mm, respectively. CONCLUSION: The present study demonstrated the normal variations of anterior segment structures of the eyes in normal Northern Thais using the Orbscan II topography system. This information may be useful for comparison with further quantitative studies of various abnormal states.

Adult↗

PubMed1990

Reading, writing and the Texas supplement to the essential elements for the hearing impaired.

Students need educational programs which foster maximum development of their personal knowledge, skill, and competence. To accomplish this, they should have access to a well-balanced curriculum, effective instruction and opportunities to succeed. In accordance with this philosophy, the 67th and 68th Legislatures of the State of Texas (1981-1984) established rules and procedures for the implementation of a state basic curriculum. Under this mandate, school districts are required to implement the provisions of these rules in "a manner which will enable all students to participate actively in a well-balanced curriculum and master, to the best of their ability, the knowledge, skills, and competencies established through the essential elements," in order to become accredited by the Texas Education Agency. To meet these requirements and make the goals wholly appropriate for hearing-impaired students in Texas, the Division of Services for the Deaf of the Texas Education Agency developed an in-depth expansion of these state-mandated essential elements in the area of English Language Arts, grades K-8. This expansion, the Supplement to the Essential Elements for the Hearing Impaired (SEE-HI) includes the original language arts essential elements as well as supplemental goals and sub-goals necessary for students who have language deficiencies, especially those caused by hearing loss.

Accreditation↗

PubMed2003

Reading a population code: a multi-scale neural model for representing binocular disparity.

Although binocular neurons in the primary visual cortex are sensitive to retinal disparity, their activity does not constitute an unambiguous disparity signal. A multi-spatial-scale neural model for disparity computation is developed to examine how population activity might be interpreted to overcome ambiguities at the single neuron level. The model incorporates a front end that encodes disparity by a family of complex cell-like energy units and a second stage that reads the population activity. Disparity is recovered by matching the population response to a set of canonical templates, derived from the mean response to white noise stimuli at a range of disparities. Model predictions are qualitatively consistent with a variety of psychophysical results in the literature, including the effects of spatial frequency on stereoacuity and bias in perceived depths, and the effect of standing disparity on increment thresholds. Model predictions are also consistent with data on qualitative appearance of complex stimuli, including depth averaging, transparency, and corrugation. The model also accounts for the non-linear interaction of disparities in compound grating stimuli. These results show that a template-match approach reduces ambiguities in individual and pooled neuronal responses, and allows for a broader range of percepts, consistent with psychophysics, than other models. Thus, the pattern of neural population activity across spatial scales is a better candidate for the neural correlate of depth perception than the activity of single neurons or the pooled activity of multiple neurons.

Depth Perception↗

PubMed2003

Acidic solubility of luting cements.

OBJECTIVES: Chemical disintegration of luting cements can adversely affect their long term success. The aim of the present study was to assess the susceptibility of zinc phosphate cement, glass ionomer cement and resin cement to erosion at various pH values. METHODS: Zinc phosphate and glass ionomer cement samples were eroded in 0.3% citric acid adjusted to pH 3.0, 4.0, 5.0, 6.0 and 7.0 at a temperature of 35 degrees C. A control group was stored in saline. Profilometric readings were performed after 30 min and 1h erosion time. Resin cement samples were eroded at pH 3.0 with measurements after 30 min, 6h, 24h and 7 days. A saline control group was measured after 7 days. RESULTS: Erosion of zinc phosphate cement was significantly higher at all pH values than erosion of glass ionomer cement with erosion depth increasing with decreasing citric acid pH. No erosion was seen in the control groups. The resin cement did not show any change in surface profile after the 7 day erosion period compared to the control group. Comparison to dental tissues revealed that erosion of glass ionomer cement in vitro was slightly lower than erosion of enamel and dentine. In contrast, erosion of zinc phosphate cement was much higher.

Acids↗

PubMed1993

Responsible conduct of scientific research: a one-semester course for graduate students.

This course was developed to satisfy in part the requirement that "a program in the principles of scientific integrity" be a part of any training program funded by the National Institutes of Health (NIH) or the Alcohol, Drug Abuse, and Mental Health Administration (NIH "Guide for Grants and Contracts," vol. 18, no. 45, 1989). The booklet On Being A Scientist (National Academy of Sciences, 1989) was chosen as required reading. The issues were presented in 15 1-h sessions. Public policy issues were not addressed. A danger was to be overly critical of scientific misconduct and stimulate a cynical skepticism of the integrity of the working scientist. One problem is that there are only general procedures a student can follow when encountering misconduct. Numerous guest speakers provided depth, objectivity, and authenticity to the discussion.

Biomedical Research↗

PubMed2002

Caring for seriously mentally ill patients. Qualitative study of family physicians' experiences.

OBJECTIVE: To examine family physicians' experiences in caring for patients with serious mental illness and their expectations of a shared mental health care (SMHC) model. DESIGN: Qualitative method of in-depth interviews. SETTING: London, Ont. PARTICIPANTS: Purposive sample of 11 full-time family physicians providing ongoing care for patients with serious mental illness. METHOD: Eleven interviews were conducted to explore family physicians' experiences. All interviews were audiotaped and transcribed verbatim. Analysis was done using a constant comparative approach and was carried out concurrently rather than sequentially. Researchers read all interview transcripts independently before comparing and combining their analyses. Final analysis involved examining all interviews together to discover relationships between and among emerging themes. MAIN FINDINGS: Findings reflected three main themes: what family physicians perceive they bring to care of seriously mentally ill patients (i.e., whole-person approach to care); challenges family physicians face in participating in shared care of these patients (i.e., communication and access issues); and family physicians' expectations of a SMHC model (i.e., guidance and feedback). CONCLUSION: As seriously mentally ill patients are moved out of institutions, the need for an effective and efficient SMHC model becomes imperative. Our findings suggest that family physicians could be an important part of SMHC models but only if systemic barriers are removed and collaborative practice is encouraged.

Attitude of Health Personnel↗

PubMed1987

Strategies for visual word recognition and orthographical depth: a multilingual comparison.

We investigated the psychological reality of the concept of orthographical depth and its influence on visual word recognition by examining naming performance in Hebrew, English, and Serbo-Croatian. We ran three sets of experiments in which we used native speakers and identical experimental methods in each language. Experiment 1 revealed that the lexical status of the stimulus (high-frequency words, low-frequency words, and nonwords) significantly affected naming in Hebrew (the deepest of the three orthographies). This effect was only moderate in English and nonsignificant in Serbo-Croatian (the shallowest of the three orthographies). Moreover, only in Hebrew did lexical status have similar effects on naming and lexical decision performance. Experiment 2 revealed that semantic priming effects in naming were larger in Hebrew than in English and completely absent in Serbo-Croatian. Experiment 3 revealed that a large proportion of nonlexical tokens (nonwords) in the stimulus list affects naming words in Hebrew and in English, but not in Serbo-Croatian. These results were interpreted as strong support for the orthographical depth hypothesis and suggest, in general, that in shallow orthographies phonology is generated directly from print, whereas in deep orthographies phonology is derived from the internal lexicon.

Discrimination Learning↗

PubMed1998

Depth-of-processing effects on priming in stem completion: tests of the voluntary-contamination, conceptual-processing, and lexical-processing hypotheses.

Depth-of-processing effects on incidental perceptual memory tests could reflect (a) contamination by voluntary retrieval, (b) sensitivity of involuntary retrieval to prior conceptual processing, or (c) a deficit in lexical processing during graphemic study tasks that affects involuntary retrieval. The authors devised an extension of incidental test methodology--making conjunctive predictions about response times as well as response proportions--to discriminate among these alternatives. They used graphemic, phonemic, and semantic study tasks, and a word-stem completion test with incidental, intentional, and inclusion instructions. Semantic study processing was superior to phonemic study processing in the intentional and inclusion tests, but semantic and phonemic study processing produced equal priming in the incidental test, showing that priming was uncontaminated by voluntary retrieval--a conclusion reinforced by the response-time data--and that priming was insensitive to prior conceptual processing. The incidental test nevertheless showed a priming deficit following graphemic study processing, supporting the lexical-processing hypothesis. Adding a lexical decision to the 3 study tasks eliminated the priming deficit following graphemic study processing, but did not influence priming following phonemic and semantic processing. The results provide the first clear evidence that depth-of-processing effects on perceptual priming can reflect lexical processes, rather than voluntary contamination or conceptual processes.

Adult↗

PubMed2004

'I am not the kind of woman who complains of everything': illness stories on self and shame in women with chronic pain.

In this study, we explore issues of self and shame in illness accounts from women with chronic pain. We focused on how these issues within their stories were shaped according to cultural discourses of gender and disease. A qualitative study was conducted with in-depth interviews including a purposeful sampling of 10 women of varying ages and backgrounds with chronic muscular pain. The women described themselves in various ways as 'strong', and expressed their disgust regarding talk of illness of other women with similar pain. The material was interpreted within a feminist frame of reference, inspired by narrative theory and discourse analysis. We read the women's descriptions of their own (positive) strength and the (negative) illness talk of others as a moral plot and argumentation, appealing to a public audience of health personnel, the general public, and the interviewer: As a plot, their stories attempt to cope with psychological and alternative explanations of the causes of their pain. As performance, their stories attempt to cope with the scepticism and distrust they report having been met with. Finally, as arguments, their stories attempt to convince us about the credibility of their pain as real and somatic rather than imagined or psychological. In several ways, the women negotiated a picture of themselves that fits with normative, biomedical expectations of what illness is and how it should be performed or lived out in 'storied form' according to a gendered work of credibility as woman and as ill. Thus, their descriptions appear not merely in terms of individual behaviour, but also as organized by medical discourses of gender and diseases. Behind their stories, we hear whispered accounts relating to the medical narrative about hysteria; rejections of the stereotype medical discourse of the crazy, lazy, illness-fixed or weak woman.

Adult↗

PubMed1991

Application of robotics and image processing to automated colony picking and arraying.

We describe a system that applies image processing and robotic techniques to automatically pick individual colonies from square petri dishes and array them in 96-well microtiter plates. Digital images of the colony distribution in the dishes are acquired using a video camera and frame buffer. Commercial image processing software is used to identify individual colonies and determine their locations. A Hewlett-Packard Microassay System robot reads the resulting coordinate file for each dish, picks cells from each identified colony and transfers the cells into a microtiter plate well. A disposable pipet tip is used as the sterile implement for colony picking. Custom holders position the dishes accurately and provide common coordinate systems for imaging and picking. The system is calibrated to account for the depth of agar in the dishes. The robot can process up to 10 dishes and 20 plates (1920 colonies) in a single run. It has successfully arrayed a cosmid library of the S. pombe genome consisting of approximately 6000 colonies in 30 petri dishes in about 40 hours of robot time. Future enhancements to the system are discussed.

Cells, Cultured↗

PubMed2004

Enamel loss associated with orthodontic adhesive removal on teeth with white spot lesions: an in vitro study.

Teeth with white spot lesions (WSL) might be more prone to enamel loss during bracket debonding. This in vitro study compared enamel loss from teeth with (n = 14) and without (n = 14) WSL after polishing with low-speed finishing burs or disks (Sof-Lex, 3M ESPE, St Paul, Minn). Debonded surfaces were analyzed with a contact stylus profilometer, and digitized data were compared with baseline readings by using AnSur NT software (Regents, University of Minnesota, Minneapolis, Minn). Specimen surfaces were also examined with a scanning electron microscope. Two-way analysis of variance was performed to analyze the data. In teeth without WSL, the volume losses were 0.16 mm(3) for the bur group and 0.10 mm(3) for the disk group; the mean maximum depths were 47.7 microm for the bur group and 54.3 microm for the disk group. In teeth with WSL, the volume losses were 0.06 and 0.17 mm(3), and the mean maximum depths were 35.1 and 48.7 microm for the bur and disk groups, respectively. There were no significant differences in enamel loss between the 2 groups of teeth without WSL (P =.12). However, in teeth with WSL, the burs removed less enamel than the disks (P = 0.006). Scanning electron microscope examination showed that any damage on the enamel surface was usually located in the cervical third of the teeth. On most specimens, even though tooth surfaces appeared resin-free to the naked eye, there were remnants of it. The differences between groups were so small that they might be clinically insignificant.

Analysis of Variance↗

PubMed2000

Temperatures in and around mandibular fractures.

This study measured the temperature in and around mandibular fractures in 20 anaesthetized patients. A fine calibrated thermocouple attached to a digital thermometer was used to measure temperature at the bone surface margin of a mandibular fracture and 5 and 10 mm from the fracture; within the fracture against the bone at 5, 7 and 10 mm depths and at the base of 7 mm deep biopsy cavities 5 and 10 mm distant from the fracture line immediately after biopsy, then 1 and 2 min later. On the surface the temperature was approximately 1 degrees C warmer than at the 5 and 10 mm sites distant from the fracture. Temperature reduced at the 1 and 2 min readings after the biopsy cavity cutting. This study confirmed that the surface temperature is lower than internal bone temperatures.

Adult↗

PubMed1996

Directed case study method for teaching human anatomy and physiology.

A mastery of human anatomy and physiology requires a familiarity with a vast number of details about the human body. A directed method of case analysis is described that helps students deepen and solidify their understanding of anatomical and physiological facts, concepts, and principles. The successful case had four distinctive features as follows: clear learning objectives, a concise and informative scenario, straightforward and didactic questions, and an emphasis on information readily available to the student. A directed case study is presented, and its salient features are described. A procedure for integrating case analyses into an undergraduate anatomy and physiology course is outlined. Student response to this type of case study suggests that this method improves the ease of learning, the depth of learning, and an appreciation of the relevance of and a curiosity about anatomy and physiology. The addition of case analyses to a two-semester integrated course in anatomy and physiology was also associated with an improvement in exam performance. The regular use of directed case analysis is a valuable addition to the traditional methods of lecture, textbook reading, and laboratory for the teaching of human anatomy and physiology.

Anatomy↗