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PubMed2002

Automated 3-D echocardiography analysis compared with manual delineations and SPECT MUGA.

A major barrier for using 3-D echocardiography for quantitative analysis of heart function in routine clinical practice is the absence of accurate and robust segmentation and tracking methods necessary to make the analysis automatic. In this paper, we present an automated three-dimensional (3-D) echocardiographic acquisition and image-processing methodology for assessment of left ventricular (LV) function. We combine global image information provided by a novel multiscale fuzzy-clustering segmentation algorithm, with local boundaries obtained with phase-based acoustic feature detection. We then use the segmentation results to fit and track the LV endocardial surface using a 3-D continuous transformation. To our knowledge, this is the first report of a completely automated method. The protocol is evaluated in a small clinical case study (nine patients). We compare ejection fractions (EFs) computed with the new approach to those obtained using the standard clinical technique, single-photon emission computed tomography multigated acquisition. Errors on six datasets were found to be within six percentage points. A further two, with poor image quality, improved upon EFs from manually delineated contours, and the last failed due to artifacts in the data. Volume-time curves were derived and the results compared to those from manual segmentation. Improvement over an earlier published version of the method is noted.

Algorithms↗
PubMed2004

FT-Raman spectroscopy of calcium hydroxide medicament in root canals.

AIM: To investigate chemical changes in calcium hydroxide introduced into human root canals as a medicament using Fourier transform-(FT) Raman spectroscopy. METHODOLOGY: Ten necrotic maxillary anterior teeth were selected in 10 patients. The teeth were divided into five treatment groups, according to the survey time. Root canal instrumentation was performed with hand instruments until the master apical file was size 40. Calcium hydroxide paste, in a 1 : 1.25 mixture by weight of powder and distilled water, was introduced directly into the root canal with a lentulo-spiral filler and then condensed with a finger plugger. The access cavity was sealed with a temporary dressing. After 2 and 4 days, then 2, 4 and 6 weeks, the calcium hydroxide paste was sampled with a K-file and then analysed using FT-Raman spectroscopy. The excitation source was an Nd : YAG laser with an excitation wavelength of 1064 nm. All spectra were taken with a laser power of 200 mW, 275-1185 scans, and 4 cm(-1) resolution. The conversion of calcium hydroxide to calcium carbonate was calculated on the basis of the spectral data obtained from the mixtures of both compounds. RESULTS: The calcium hydroxide paste in the apical region showed weak bands at 1088 and 284 cm(-1), in addition to bands associated with calcium hydroxide. The weak bands, assigned to calcium carbonate, became stronger with time. Calcium carbonate content increased rapidly in the first 2 days and then tended to increase slowly. Approximately 11% of the calcium hydroxide at the apical portion of the canal was converted to calcium carbonate after 6 weeks. However, little alteration of the paste was noticed in the samples from the middle portion of the canal. CONCLUSIONS: Calcium hydroxide medicament in root canals became transformed into calcium carbonate in the apical region within 2 days. Although the transformation continued with time, approximately 90% of the calcium hydroxide remained unchanged after 6 weeks.

Calcium Carbonate↗
PubMed1999

Satellite Evidence for an Arctic Sea Ice Cover in Transformation.

Recent research using microwave satellite remote sensing data has established that there has been a reduction of about 3 percent per decade in the areal extent of the Arctic sea ice cover since 1978, although it is unknown whether the nature of the perennial ice pack has changed. These data were used to quantify changes in the ice cover's composition, revealing a substantial reduction of about 14 percent in the area of multiyear ice in winter during the period from 1978 to 1998. There also appears to be a strong correlation between the area of multiyear ice and the spatially averaged thickness of the perennial ice pack, which suggests that the satellite-derived areal decreases represent substantial rather than only peripheral changes. If this apparent transformation continues, it may lead to a markedly different ice regime in the Arctic, altering heat and mass exchanges as well as ocean stratification.

Journal Article↗
PubMed1990

T-cell lymphoma lines derived from rat thymomas induced by Moloney murine leukemia virus: phenotypic diversity and its implications.

The phenotype of 27 Moloney murine leukemia virus-induced rat thymic lymphomas and 36 cell lines derived from these tumors was determined by using 18 monoclonal antibodies directed against hematopoietic cell surface determinants. The cell lines and the primary tumors from which they were derived were clonally related as determined by the pattern of provirus integration and the pattern of rearrangement of the T-cell receptor beta and delta and Igh loci. The differentiation phenotype of the primary tumors and the cell lines derived from them were related. The differences observed between the primary tumors and the cell lines could be explained either by the selection of subpopulations of tumor cells during establishment in culture or by the phenotypic instability of the tumor cells. One cell line (LE3Sp) underwent the transition from a CD4+ CD8+ to a CD4+ CD8- phenotype following exposure to interleukin-2 in culture. Both the primary tumors and the cell lines derived from them express a wide range of phenotypes which correspond to multiple stages in T-cell development. This observation suggests that the pleiomorphism of retrovirus-induced lymphomas, which had been suggested previously from the analysis of mouse tumors, is an intrinsic property of the process of oncogenesis and is not due to the transformation of different types of cells by spontaneously arising leukemogenic variants of the inoculated virus. The wide spectrum of phenotypes expressed by these tumors suggests that Moloney murine leukemia virus may infect and transform T cells at various stages of development. Alternatively, the target cells may be immature T-cell precursors which, following transformation, continue to differentiate. A host of early findings, suggesting that the repertoire of target cells is restricted to poorly differentiated hematopoietic progenitors, and the ability of the LE3Sp cell line to differentiate in culture indicate that the latter possibility may be more likely. The data in this report address the extent and mechanism of the phenotypic variability of retrovirus-induced rodent T-cell lymphomas. In addition, they demonstrate the potential usefulness of the T-cell lymphoma lines we have established in studies of oncogenesis and T-cell differentiation.

Animals↗
PubMed2005

How ADAM-9 and ADAM-11 differentially from estrogen receptor predict response to tamoxifen treatment in patients with recurrent breast cancer: a retrospective study.

PURPOSE: To evaluate the predictive value of the disintegrin and metalloproteinases, ADAM-9, ADAM-10, ADAM-11, and ADAM-12, and of the matrix metalloproteinases, MMP-2 and MMP-9, in patients with recurrent breast cancer treated with tamoxifen. EXPERIMENTAL DESIGN: A retrospective study was done on 259 frozen specimens of estrogen receptor-positive primary breast carcinomas from patients who developed recurrent disease and were treated with tamoxifen as the first line of therapy. The expression levels of the biological factors were assessed by real-time quantitative reverse transcriptase PCR. RESULTS: Using log-transformed continuous variables, increasing levels of ADAM-9 [odds ratio (OR) = 1.41; P = 0.015] and decreasing levels of MMP-9 (OR, 0.81; P = 0.035) predicted favorable disease control independent from the traditional predictive factors. Furthermore, when tumors were dichotomized at the median level of 70% tumor cell nuclei, our univariate analysis showed particularly strong results for the group of 153 patients with primary tumors containing 30% or more stromal cells. Although estrogen receptor levels lost their predictive power for this group of patients, high levels of ADAM-9 (OR, 1.59; P = 0.007) and ADAM-11 (OR, 1.65; P = 0.001) were significantly associated with a higher efficacy of tamoxifen therapy. CONCLUSIONS: Our results show that especially for primary tumors containing stromal elements, the assessment of mRNA expression levels of ADAM-9 and ADAM-11 could be useful to identify patients with recurrent breast cancer who are likely to benefit or fail from tamoxifen therapy.

ADAM Proteins↗
PubMed2006

The role of memory in guiding attention during natural vision.

What is the time frame in which perceptual memory guides attention? Current estimates range from a few hundred milliseconds to several seconds, minutes, or even days. Here, we answer this question by establishing the time course of attentional selection in realistic viewing conditions. First, we transformed continuous video clips into MTV-style video clips by stringing together continuous clip segments using abrupt transitions (jump cuts). We then asked participants to visually explore either continuous or MTV-style clips and recorded their saccades as objective behavioral indicators of attentional selections. The utilization of perceptual memory was estimated across viewing conditions and over time by quantifying the agreement between human attentional selections and predictions made by a neurally grounded computational model. In the critical condition, jump cuts led to sharp declines in the impact of perceptual memory on attentional selection, followed by monotonic increases in memory utilization across seven consecutive saccades and 2.5 s. These results demonstrate that perceptual memory traces play an important role in guiding attention across several saccades during natural vision. We propose novel hypotheses and experiments using hybrid natural-artificial stimuli to further elucidate neurocomputational mechanisms of attentional selection.

Adult↗
PubMed1997

Toward parsimony in the inpatient community meeting on a short-term unit.

The role of the community meeting on the inpatient psychiatric unit has been continuously transformed by the radical shifts in the practice of inpatient psychiatry over the past 40 years. The current clinical climate of extremely shortened lengths of stay requires the community meeting to directly address the inpatient unit's primary tasks of stabilization, discharge planning, and treatment compliance and to avoid the regressive effects of large, unstructured groups. In these conditions, an interpretive model of the community meeting, which addresses patients' projections onto staff behavior, seems problematic and not widely applicable because it turns patients' attention away from the adaptational challenges they face from their external social environments. It also places heavy demands on staff time, training, and tolerance.

Adaptation, Psychological↗
PubMed2005

The "lipid accumulation product" performs better than the body mass index for recognizing cardiovascular risk: a population-based comparison.

BACKGROUND: Body mass index (BMI, kg/m2) may not be the best marker for estimating the risk of obesity-related disease. Consistent with physiologic observations, an alternative index uses waist circumference (WC) and fasting triglycerides (TG) concentration to describe lipid overaccumulation. METHODS: The WC (estimated population minimum 65 cm for men and 58 cm for women) and TG concentration from the third National Health and Nutrition Examination Survey (N = 9,180, statistically weighted to represent 100.05 million US adults) were used to compute a "lipid accumulation product" [LAP = (WC-65) x TG for men and (WC-58) x TG for women] and to describe the population distribution of LAP. LAP and BMI were compared as categorical variables and as log-transformed continuous variables for their ability to identify adverse levels of 11 cardiovascular risk factors. RESULTS: Nearly half of the represented population was discordant for their quartile assignments to LAP and BMI. When 23.54 million with ordinal LAP quartile > BMI quartile were compared with 25.36 million with ordinal BMI quartile > LAP quartile (regression models adjusted for race-ethnicity and sex) the former had more adverse risk levels than the latter (p < 0.002) for seven lipid variables, uric acid concentration, heart rate, systolic and diastolic blood pressure. Further adjustment for age did not materially alter these comparisons except for blood pressures (p > 0.1). As continuous variables, LAP provided a consistently more adverse beta coefficient (slope) than BMI for nine cardiovascular risk variables (p < 0.01), but not for blood pressures (p > 0.2). CONCLUSION: LAP (describing lipid overaccumulation) performed better than BMI (describing weight overaccumulation) for identifying US adults at cardiovascular risk. Compared to BMI, LAP might better predict the incidence of cardiovascular disease, but this hypothesis needs prospective testing.

Adolescent↗
PubMed1994

THE SHIFT IN VISUAL PIGMENT DOMINANCE IN THE RETINAE OF JUVENILE COHO SALMON (ONCORHYNCHUS KISUTCH): AN INDICATOR OF SMOLT STATUS

Smolting juvenile coho salmon were sampled to determine (1) whether a correlation between hypo-osmoregulatory ability and visual pigment composition existed and (2) whether the hormone 3,5,3'-tri-iodothyronine (T3) was playing a role in the visual pigment conversion process. Plasma sodium levels of seawater-challenged fish (30 ) indicated that there was a 5 week period of optimal ability to excrete excess plasma sodium ions (hypo-osmoregulation) in the late spring/early summer that represented the 'window of opportunity' for the entry or introduction to sea water of the salmon. Early in the smoltification process, the vitamin-A2-based visual pigment porphyropsin increased its dominance in the retinae, and radioimmunoassay of plasma indicated that T3 levels were at a maximum prior to this increase in porphyropsin. As the parr&shy;smolt transformation continued, there was a steady decrease in the relative amounts of porphyropsin, indicating that the retinae were favouring the acquisition of rhodopsin. Rhodopsin dominance virtually coincided with the period of best hypo-osmoregulatory ability. Subsequently, the salmon showed a loss of hypo-osmoregulatory ability and concomitant increases in the amount of porphyropsin in the retina were observed. The relationship between the visual pigment shift and the smoltification process is discussed in terms of preparation for migration and thyroid hormone involvement, and the use of retinal visual pigment composition as an index of smolt status is proposed.

Journal Article↗
PubMed2001

From pigsties to hog heaven?

In the continuing transformation of U.S. agriculture, North Carolina finds itself on the front edge of change. Between 1989 and 1998, the number of hogs in the state's pork industry quintupled---and so has the amount of hog waste that must be disposed of. Now the state has engaged private and public resources in a rapid search for better ways for handling hog waste. A technology review panel has approved the first round of proposals for a number of novel technologies to be developed through funds from a government-industry agreement. A second batch of proposals is expected to be approved by late summer.

Agriculture↗
PubMed1997

The impact of managed care on Massachusetts mental health and substance abuse providers.

Medicaid managed care programs are becoming more widespread. To investigate the clinical, organizational, and financial impacts on service providers, a stratified, random sample of providers in the Massachusetts Managed Mental Health/Substance Abuse Program were surveyed by phone in Years 3 and 4 of the initiative. Providers reported that they were making widespread clinical changes such as more use of group, brief, and episodic therapies. They were increasing utilization review, Total Quality Management, and outcomes measurement. They were increasing in size, affiliating with other agencies, and providing a greater range of services. They were preparing for capitation. Compared to before the program and a year earlier, about 40 percent of providers were doing better financially and a quarter were doing worse. The study documents the hypothesis that a widespread and continuing transformation is taking place in response to managed care.

Cost Control↗
PubMed2005

Optical clearing for improved contrast in second harmonic generation imaging of skeletal muscle.

Using second harmonic generation (SHG) imaging microscopy, we have examined the effect of optical clearing with glycerol to achieve greater penetration into specimens of skeletal muscle tissue. We find that treatment with 50% glycerol results in a 2.5-fold increase in achievable SHG imaging depth. Signal processing analyses using fast Fourier transform and continuous wavelet transforms show quantitatively that the periodicity of the sarcomere structure is unaltered by the clearing process and that image quality deep in the tissue is improved with clearing. Comparison of the SHG angular polarization dependence also shows no change in the supramolecular organization of acto-myosin complexes. By contrast, identical treatment of mouse tendon (collagen based) resulted in a strong decrease in SHG response. We suggest that the primary mechanism of optical clearing in muscle with glycerol treatment results from the reduction of cytoplasmic protein concentration and concomitant decrease in the secondary inner filter effect on the SHG signal. The lack of glycerol concentration dependence on the imaging depth indicates that refractive index matching plays only a minor role in the optical clearing of muscle. SHG and optical clearing may provide an ideal mechanism to study physiology in highly scattering skeletal or cardiac muscle tissue with significantly improved depth of penetration and achievable imaging depth.

Animals↗
PubMed2006

[Health promotion groups for improving autonomy, living conditions and health].

This article presents the methodology of Health Promotion Groups, which were conceived as a means of contributing towards developing autonomy, improving living conditions and promoting health. The method is identified as a collective and interdisciplinary health intervention, consisting of a group process. It guides the development of attitudes and behavioral patterns towards continually transforming participants' health levels and living conditions. The Health Promotion Groups are identified within the context of the National Health System (Sistema Unico de Saúde) as a means of surpassing the biomedical model. It stimulates the development of actions in which the positive aspects of health are emphasized, while at the same time it can serve to more effectively meet the demands for care for the elderly in health systems.

Aged↗
PubMed1975

The occurrence of brown adipose tissue in perirenal fat in Japanese.

1. In 125 cases of perirenal fat samples derived from human necropsies (from 1 month to 86 years), the occurrence of the brown adipose tissue was examined. Brown fat cells were contained in 72% (90: 125) of the cases. 2. In the infants, all samples contained maximal amounts of brown fat cells: the perirenal fat was composed almost exclusively of brown fat cells: in children and teenagers they began to diminish, and in younger adults further reductions were observed: after the fifth decade conspicuous diminutions occurred. In later decades the brown fat in the perirenal fat was small in amount. 3. This change in the amount of the brown fat tissue undergoes individual variations. In some cases, the brown fat tissue disappeared from perirenal fats in the early stages of life, while in others it persisted to very late stages of life. A man as old as 86 years possessed brown adipose cells in the perirenal fat. 4. Multilocular brown fat cells were classified into the following types: Type 1, fat-depleted cells: Type 2, small-locular cells: Type 3, middle-locular cells: Type 4, large-locular cells: Type 5, monolocular brown fat cells with a thick cytoplasmic rim and pseudomonolocular brown fat cells and Type 6, multilocular brown fat cells rich in cytoplasm. In the infants, all cell types were identified: the small-locular cells were in general scanty in all decades following infancy: in later decades of life, the most common cell types were middle-locular and large-locular cells. The fat-depleted cell is a particular cell type and may occur usually accompanied by multilocular brown fat cells rich in cytoplasm. 5. The fat lobules are composed of a centrally located brown fat cell area and a peripheral layer of monolocular white fat cells, which in the infants was very thin but in the following ages was gradually widened to invade the interior of the lobules. 6. The present findings suggest a continuous replacement of brown fat cells by white fat cells during advancing age. The monolocular brown fat cell with a thick cytoplasmic rim and the pseudomonolocular brown fat cells probably represent transitional forms between multilocular brown fat and monolocular white fat cells. These cell types were found throughout life, suggesting continuous transformation of the brown fat cell into the white fat cell.

Adipose Tissue, Brown↗
PubMed2006

Occupational diseases in the period of socioeconomic transition in Poland.

OBJECTIVES: Current situation in the epidemiology of occupational diseases is a resultant of many contributing factors, such as occupational exposures of the working population, social and economic conditions, medical measures, legislation, and ongoing changes in the national economy. MATERIALS AND METHODS: This work is based on the information compiled from reporting forms on occupational diseases gathered in the Central Register of Occupational Diseases run by the Nofer Institute of Occupational Medicine, Lódź, Poland. RESULTS: A systematic downward trend in the number of occupational diseases has already been observed over several years. In 1998, as many as 12 017 cases were recorded (117.3 per 100,000 workers), while in 2005, this number was reduced to 3249 (34.8 per 100 000). In 2005, the highest incidence rates were noted for chronic voice disorders, pneumoconioses, infectious and parasitic diseases, hearing loss, and skin diseases. The observed decrease in occupational pathology is associated with continued transformations in the national economy. Changes in the nature and level of occupational exposures have influenced the profile of occupational pathologies. Medical preventive measures, such as vaccinations covering high-risk groups have contributed to the reduced incidence of occupational diseases. For example, the number of cases of occupation-related viral hepatitis was seven times lower in 2005 than in 1993. The 2005 data show that over 50% of occupational diseases were diagnosed in workers employed outside industry. CONCLUSIONS: Changes taking place on the labor market, new technologies and most of all transfer of the workforce from industry to the service and administration sectors, will certainly affect the profile of occupational and work-related pathologies. In the present-day environment, the work-related stress has become a dominant factor.

Adult↗
PubMedDate not supplied

[Classifications and the building up of nursing knowledge].

In the course of this article, knowledge is focused on as a process, a series of continuous transformations. Evolutionary aspects of knowledge in nursing are presented. Considerations are taken into account concerning the human language and its significance as well as the conceptual development and classifications to be used in professional actions. Nursing Classification Systems are briefly described and their importance in the building of knowledge in the nursing area is emphasized.

Classification↗
PubMed1997

The Genesis Enterprise: creating peak-to-peak performance.

Peak performance is often the beginning of failure. The process of continuously creating peak-to-peak performance defines the Genesis Enterprise. There will always be more problems than there are solutions. We need to install a process that anticipates and solves problems before they are problems and to continuously transform our organization into a championship organization that is nevertheless the underdog.

Humans↗
PubMed1998

[The structure of meta-ethical reasoning and "paradigmatic instability" of medicine].

Meta-ethics is such a philosophical discipline that it analyses meaning and logical status of moral conceptions and arguments. Its scope of interest is focused on such problems, among others, as to what extent are moral values the intrinsic part of our reality and, on the other hand, to what extent are they merely the expression or certain conventions, emotions or directives. Codes of medical ethics and other legal acts concerning ethical commitments, both domestic and international (as, for example, Declaration of Helsinki), are based on a certain hidden meta-ethical presumption that morality is a human creation, and thus it belongs to a certain so-called "social realm". As such, medical ethics undergoes continuous transformations with regard to technological progress, which creates new moral challenges. This frequently leads to conflicts between moral, legal and praxiological norms under the absence of consensual conformity of utilitarian and deontological ways of moral reasoning. It may be useful for medical ethics to differentiate between axiological and thetic norms that are present in codes of medical ethics and in various international bioethical declarations and conventions.

Ethics, Medical↗