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PubMedDate not supplied

Malposition of pediatric gastric lavage tubes demonstrated radiographically.

Gastric lavage may be indicated in the initial treatment of toxic substance ingestion. We retrospectively surveyed the charts of 36 pediatric patients who underwent gastric lavage to evaluate the clinical and radiographic evidence indicating proper tube placement. Only 14 patients had a radiograph prior to lavage, and 50% of these documented malposition. The most common was excess tube insertion, stretching the stomach inferiorly towards the pelvis. The traditionally acceptable clinical test by auscultation of insufflated air was favorable in 100% of patients, thus failing to detect all of the malpositionings documented radiographically. We suggest that initial insertion of tube length be based on the patient's height or length using an adaptation of Strobel's previously published formula for esophageal pH probe placement: Tube Insertion Depth (TID), orogastric = 9.7 cm + (0.226 x length of patient in cm) and TID, nasogastric = 8 cm + (0.252 x length of patient in cm). These formulae have been displayed in graphic form for easy use. Diagnostic imaging remains the only certain means to document tube placement. Prospective studies to validate the formulae in clinical use are ongoing.

Adolescent↗

PubMed1998

Physiology and molecular phylogeny of coexisting Prochlorococcus ecotypes.

The cyanobacterium Prochlorococcus is the dominant oxygenic phototroph in the tropical and subtropical regions of the world's oceans. It can grow at a range of depths over which light intensities can vary by up to 4 orders of magnitude. This broad depth distribution has been hypothesized to stem from the coexistence of genetically different populations adapted for growth at high- and low-light intensities. Here we report direct evidence supporting this hypothesis, which has been generated by isolating and analysing distinct co-occurring populations of Prochlorococcus at two locations in the North Atlantic. Co-isolates from the same water sample have very different light-dependent physiologies, one growing maximally at light intensities at which the other is completely photoinhibited. Despite this ecotypic differentiation, the co-isolates have 97% similarity in their 16S ribosomal RNA sequences, demonstrating that molecular microdiversity, commonly observed in microbial systems, can be due to the coexistence of closely related, physiologically distinct populations. The coexistence and distribution of multiple ecotypes permits the survival of the population as a whole over a broader range of environmental conditions than would be possible for a homogeneous population.

Cyanobacteria↗

PubMed1994

A closer look at social support as a moderator of stress in breast cancer.

This study explored the effects of perceived social support from friends, family, and spouses on the psychological adjustment of 135 newly diagnosed breast cancer patients. Initial data analyses revealed moderate correlations between greater psychological distress and lower levels of social support. However, when the personality variable of social desirability was controlled for, the relationship between social support and well-being were substantially weakened or eliminated. It is concluded that characteristics of the person, rather than of the situation, underlie the apparent relationship between social support and adjustment to illness. Social workers are advised to make in-depth assessments of ego strengths and past psychological functioning as better predictors of patient adaptation to disease.

Adaptation, Psychological↗

PubMed1997

Laminar analysis of cerebral blood flow in cortex of rats by laser-Doppler flowmetry: a pilot study.

Laser-Doppler flowmetry (LDF) is a reliable method for estimation of relative changes of CBF. The measurement depth depends on wavelength of the laser light and the separation distance of transmitting and recording optical fibers. We designed an LDF probe using two wavelengths of laser light (543 nm and 780 nm), and three separation distances of optical fibers to measure CBF in four layers of the cerebral cortex at the same time. In vitro comparison with electromagnetic flow measurements showed linear relationship between LDF and blood flow velocity at four depths within the range relevant to physiologic measurements. Using artificial brain tissue slices we showed that the signal for each channel decreased in a theoretically predictable fashion as a function of slice thickness. Application of adenosine at various depths in neocortex of halothane-anesthetized rats showed a predominant CBF increase at the level of application. Electrical stimulation at the surface of the cerebellar cortex demonstrated superficial predominance of increased CBF as predicted from the distribution of neuronal activity. In the cerebellum, hypercapnia increased CBF in a heterogeneous fashion, the major increase being at apparent depths of approximately 300 and 600 microns, whereas in the cerebral cortex, hypercapnia induced a uniform increase. In contrast, the CBF response to cortical spreading depression in the cerebral cortex was markedly heterogeneous. Thus, real-time laminar analysis of CBF with spatial resolution of 200 to 300 microns may be achieved by LDF. The real-time in depth resolution may give insight into the functional organization of the cortical microcirculation and adaptive features of CBF regulation in response to physiologic and pathophysiologic stimuli.

Animals↗

PubMed2002

Interocular velocity difference contributes to stereomotion speed perception.

Two experiments are presented assessing the contributions of the rate of change of disparity (CD) and interocular velocity difference (IOVD) cues to stereomotion speed perception. Using a two-interval forced-choice paradigm, the perceived speed of directly approaching and receding stereomotion and of monocular lateral motion in random dot stereogram (RDS) targets was measured. Prior adaptation using dysjunctively moving random dot stimuli induced a velocity aftereffect (VAE). The degree of interocular correlation in the adapting images was manipulated to assess the effectiveness of each cue. While correlated adaptation involved a conventional RDS stimulus, containing both IOVD and CD cues, uncorrelated adaptation featured an independent dot array in each monocular half-image, and hence lacked a coherent disparity signal. Adaptation produced a larger VAE for stereomotion than for monocular lateral motion, implying effects at neural sites beyond that of binocular combination. For motion passing through the horopter, correlated and uncorrelated adaptation stimuli produced equivalent stereomotion VAEs. The possibility that these results were due to the adaptation of a CD mechanism through random matches in the uncorrelated stimulus was discounted in a control experiment. Here both simultaneous and sequential adaptation of left and right eyes produced similar stereomotion VAEs. Motion at uncrossed disparities was also affected by both correlated and uncorrelated adaptation stimuli, but showed a significantly greater VAE in response to the former. These results show that (1) there are two separate, specialised mechanisms for encoding stereomotion: one through IOVD, the other through CD; (2) the IOVD cue dominates the perception of stereomotion speed for stimuli passing through the horopter; and (3) at a disparity pedestal both the IOVD and the CD cues have a significant influence.

Adaptation, Ocular↗

PubMed2004

Using the genome to understand pathogenicity.

Genome sequencing, the determination of the complete complement of DNA in an organism, is revolutionizing all aspects of the biological sciences. Genome sequences make available for scientific scrutiny the complete genetic capacity of an organism. With respect to microbes, this means we now have the unprecedented opportunity to investigate the molecular basis of commensal and virulence behavior. We now have genome sequences for a wide range of bacterial pathogens (obligate, facultative, and opportunistic); this has facilitated the discovery of many previously unidentified determinants of pathogenicity and has provided novel insights into what creates a pathogen. In-depth analyses of bacterial genomes are also providing new perspectives on bacterial physiology, molecular adaptation to a preferred niche, and genomic susceptibility to the uptake of foreign DNA, three key factors that can play a significant role in determining whether a species, or a strain, will have pathogenic potential.

Bacteria↗

PubMedDate not supplied

Acute onset concomitant esotropia: sensorial evaluation, prism adaptation test, and surgery planning.

BACKGROUND AND OBJECTIVE: Acute acquired concomitant esotropia is a rare form of strabismus that usually presents during infancy or early childhood with diplopia and minimal refractive error. The aim of this study was to evaluate the response to the prism adaptation test in a group of normosensorial patients with acute acquired concomitant esotropia and to determine its predictive value for surgical outcome. PATIENTS AND METHODS: Six patients (median age, 11 .5 years) with acute acquired concomitant esotropia underwent the prism adaptation test by applications of Fresnel press-on and prismatic lenses. The sensorial condition of each patient had been evaluated with theTNO stereopsis test, the Irvine test, Bagolini striated glasses, and the Worth four-dot test during the prism adaptation test, when maximum compensation angle was achieved, and after surgery. In all patients, surgery was performed based on the angle of the squint after the prism adaptation test. Patients were observed 1 day, 3 months, 6 months, and 1 year after surgery. RESULTS: An increase in the angle of the squint occurred in all patients during prism adaptation. The maximum value was obtained in the same amount of time whether with prisms of increasing power or by direct application of the final value of the prisms. The final prismatic value (target angle) was always the same. CONCLUSIONS: The accuracy of the patients' selection confirmed the existence of highly reproducible compensational movements to the prismatic correction in not only patients with anomalous retinal correspondence but also normosensorial patients. Prism adaptation test results were useful in these patients because of their high predictive value for the surgical treatment.

Acute Disease↗

PubMed2003

A semiquantitative approach for evaluating safety assurance levels for Salmonella spp. throughout a food production chain.

Various safety assurance measures are implemented in Switzerland throughout the food production chain to prevent foods of animal origin from being contaminated with Salmonella. The data that are generated from the implementation of these measures are dispersed and heterogeneous. This hinders a general overview and makes a comprehensive national evaluation of the safety assurance level difficult. A semiquantitative method that considers the quality and relevance of the various safety assurance measures for Salmonella spp. was developed. The method uses the data generated from the implementation of safety assurance measures on a national basis (gathered by interviewing stakeholders in the production step). By assembling and analyzing the data systematically, the safety assurance level for Salmonella spp. can be evaluated at every step of the food production chain. This method allows the detection of strengths and weaknesses of the safety system. The systematic evaluation procedures permit comparisons between production steps and product categories. The method was used for evaluating the safety assurance levels throughout the production chain of eggs and egg products in Switzerland. Results of the analysis showed that the overall safety assurance levels for Salmonella spp. at all production steps for eggs and egg products were good. The relatively straightforward implementation of the method made it particularly appropriate in the context of a preliminary evaluation. The method does not have the same high level of detail that is provided by microbial quantitative risk assessments, but it allows an analyst to provide meaningful results when the large amount of data required for a quantitative approach are not present while including the entire "farm to fork" continuum. It may be used as a basis for more in-depth assessments of food safety levels within various production sectors. The method could be adapted for evaluating the safety assurance for other zoonotic foodborne pathogens of interest, such as Campylobacter spp.

Animals↗

PubMed2006

Long-term outcomes of pediatric acquired brain injury.

Recent studies have shown that persisting deficits remain even in young children with mild brain injuries. Our 2-year study investigated patterns of recovery in children and adolescents with ABI over the past 10 years. In the first year, we retrospectively reviewed demographic information (e.g., age at injury, gender,severity, GCS, coma length, and LOS), medical status, academic and therapy interventions, psychological, emotional and cognitive,physical, social, and family issues reported by parents and clients and outcome data from an adapted version of the Mayo-Portland Adaptability Inventory. In the second year of the study, we prospectively collected in-depth information through the use of new outcome measures, questionnaires and structured interviews. We focused on the relationships between persisting limitations (academic performance, pragmatic communication, social interactions, and physical abilities) and restrictions on participation (i.e., school, social relationships, vocational,and quality of life) of children who are between 3 and 5 years post-injury.

Activities of Daily Living↗

PubMed1995

Evaluation of bi-level image converting methods for nuclear medicine image database stored in the IS&C magneto-optical disk.

1. INTRODUCTION. We have developed a report and imaging management system for nuclear medicine. The report and image data are stored in the IS&C magneto-optical disk (IS&C MOD). Nuclear medicine image data are relatively small, but they are large enough to create problems when being transported over a low-speed Hospital Information System (HIS) network. Moreover, gray scale image output devices (i.e., high-resolution displays, sonoprinters) are expensive. If high quality bi-level (black and white) images were available, images could be transferred through low-speed network with inexpensive bi-level terminals or conventional page-printers. We examined images using several bi-level image conversion techniques [1, 2] in order to determine how useful the bi-level images are and to assess their suitability for use in nuclear medicine. The images were compared with original film images by ROC analysis. The modified minimized average error method was found to be superior to other methods in bone and gallium images. Its A-values are 0.83 in gallium scan and 0.85 in bone scan. 2. MATERIALS AND METHODS. Our system consists of three digital gamma cameras, a nuclear medicine data processing unit, two UNIX stations, and two personal computers. The computers and the data processing unit are connected via Ethernet and each computer has an IS&C MOD unit. Image and report data are stored in the IS&C MOD. The computers are also connected off-line through the IS&C MOD. To evaluate image quality, bone scan images and gallium scan images (1024x512, 2048x1024 pixels and 16 bits depth) were converted to bi-level images (same pixels and one bit depth) using four methods: dither method, minimized average error method (MAE)[1], modified regional adaptation method, and constrained average method. For the dither methods, three sets of dither matrix (Fatting's, Bayer's and our original matrix) were employed. The computer images were compared with original film images by ROC analysis. 3. RESULTS. The converted bi-level images were 1/16 the size of the originals. They were transferred via Ethernet, displayed on the monochrome display, and printed using a conventional page-printer (240 dpi or 300 dpi). The A-values of the original gallium and bone images on the films were 0.89 and 0.94. Modified MAE method gave better results than other methods tested, with the gallium image using this technique reading 0.83 on the A-scale; and the bone images were 0.85. 4. DISCUSSION. Generally, nuclear medicine images require lower spatial and gray level resolution than other computer imaging techniques. We compared four bi-level image conversion methods in order to know which methods are suitable to nuclear medicine images. The ROC analysis was employed to evaluate these image qualities. The MAE methods made particular texture pattern as artifacts in the intermediate gray level area. But it can express homogeneity the neutral level. The dither method images are coarse texture. It affects detectabilities of subtle abnormal findings. 5. CONCLUSIONS. The A-z values of the modified MAE images were comparable to those of original film images. Although bone images give slightly lower values, many abnormal findings can be ascertained on bi-level images. High quality bi-level image techniques are considered to be useful for nuclear medicine image database systems.

Japan↗

PubMed1996

[Techniques of underwater intervention: means, methods, research and outlook].

In France, diving activities are practised by a large number of people, included recreational or sport divers, commercial and military divers. Different diving technics are used, depending on depth and duration of underwater interventions: human intervention under pressure (diving), one atmosphere submarine, remotely operated vehicle (ROV). The diver used specific equipment and procedures with air, heliox (oxygen -helium), hydrox (oxygen-hydrogen) or hydreliox (oxygen-hydrogen-helium) breathing gas mixtures; and for decompression, specific tables adapted to gas mixtures and underwater time exposures. In 1988, six Comex and French Navy divers worked at a record depth of 534 msw with hydreliox and in 1992 a world record onshore dive at 701 msw was performed by Comex in Marseille. These dives showed the efficiency of hydrogen diving at very deep depth. Among a lot of submarines built for undersea works, the latest in the range of Comex's innovative submarines, the "Remora 2000" combines the functions and instrumentation of an oceanographic subsea vessel with eye catching design of a recreational submarine. Now, ROV's replace more and more the diver on oil subsea offshore fields.

Decompression↗

PubMed1998

Epidermal growth factor augments adaptation following small bowel resection: optimal dosage, route, and timing of administration.

BACKGROUND: In assorted animal models of small bowel resection (SBR), exogenous epidermal growth factor (EGF) has been shown to augment intestinal adaptation. This study was designed to elucidate the optimal dose, route, and timing of exogenous EGF to boost adaptation in our murine model of SBR. METHODS: Male ICR mice underwent either 50% proximal SBR or sham surgery (bowel transection with reanastomosis) and then randomized to receive either saline or human recombinant EGF (5, 50, 150, or 300 microg/kg/day) by twice daily intraperitoneal (i.p.) injection or orogastric gavage (o.g.). At 7 days, protein and DNA content, crypt depth, and villus height were determined in the ileum. The premium dose and route was then given for 1 week either during (1 week after SBR) or after the adaptive phase (1 month after SBR). Differences between group means were analyzed using ANOVA. A P < 0.05 was considered significant. RESULTS: EGF enhanced DNA and protein content, crypt depth, and villus height to the greatest extent at a dosage of 50 microg/kg/day by the o.g. route. EGF had no significant effect on enhancing adaptation when given after the adaptive response had already occurred. CONCLUSIONS: Intestinal adaptation is optimally enhanced by a specific dose and route of EGF. Exogenous EGF enhances adaptation only during the adaptive response to SBR and not after it has already taken place. Determination of the best circumstances for EGF administration will permit a systematic approach toward understanding a mechanism for the beneficial effect of EGF during intestinal adaptation.

Adaptation, Physiological↗

PubMed2005

Passivity-based neural network adaptive output feedback control for nonlinear nonnegative dynamical systems.

The potential clinical applications of adaptive neural network control for pharmacology in general, and anesthesia and critical care unit medicine in particular, are clearly apparent. Specifically, monitoring and controlling the depth of anesthesia in surgery is of particular importance. Nonnegative and compartmental models provide a broad framework for biological and physiological systems, including clinical pharmacology, and are well suited for developing models for closed-loop control of drug administration. In this paper, we develop a neural adaptive output feedback control framework for adaptive set-point regulation of nonlinear uncertain nonnegative and compartmental systems. The proposed framework is Lyapunov-based and guarantees ultimate boundedness of the error signals corresponding to the physical system states and the neural network weighting gains. The approach is applicable to nonlinear nonnegative systems with unmodeled dynamics of unknown dimension and guarantees that the physical system states remain in the nonnegatiye orthant of the state-space for nonnegative initial conditions. Finally, a numerical example involving the infusion of the anesthetic drug midazolam for maintaining a desired constant level of depth of anesthesia for noncardiac surgery is provided to demonstrate the efficacy of the proposed approach.

Adaptation, Physiological↗

PubMed2003

Ecological characterization of Steinernema scarabaei, a scarab-adapted entomopathogenic nematode from New Jersey.

This study describes the basic ecological characteristics of the entomopathogenic nematode Steinernema scarabaei (Rhabditida: Steinernematidae) that was originally isolated from epizootics in scarab populations in New Jersey turfgrass areas. Under laboratory conditions, S. scarabaei infected a limited range of insect species and appeared best adapted to scarab larvae as hosts. It uses a widely ranging foraging strategy with a low attachment rate to mobile hosts on the soil surface but with excellent infection of sedentary host placed at >or=2 cm soil depth. It has a wide thermal activity range with optimum infectivity from 17.5 to 25 degrees C. Because of its foraging strategy and adaptation to scarab larvae as hosts, S. scarabaei has outstanding potential for the control of scarab pests.

Animals↗

PubMed1998

Enteral ornithine alpha-ketoglutarate enhances intestinal adaptation to massive resection in rats.

Ornithine alpha-ketoglutarate (OKG) has been advocated in the treatment of critically ill patients for its anabolic effect on protein metabolism. Since OKG is a precursor of glutamine, arginine, and polyamines, key substrates of intestinal metabolism and function, we investigated the influence of OKG on intestinal adaptation and trophicity and on glutamine status after small bowel resection. After massive (80%) small bowel resection, rats were enterally fed for 7 days with a standard diet supplemented with either OKG (2 g/kg/d) or an isonitrogenous amount of glycine. OKG induced an adaptative hyperplasia of the villi, demonstrated in the jejunum by an increase in the villus height to crypt depth ratio (OKG v control, 4.3+/-0.4 v 3.3+/-0.5, P < .01) along with an increase (P < .05) in ornithine decarboxylase (ODC) activity (+80%) and ornithine content (+102%). Plasma glutamine (+25%) and muscle glutamine (anterior tibialis [AT], +43%; extensor digitorum longus [EDL], +54%) and protein (AT, +32%) were significantly higher (P < .05) after OKG administration, supporting its role in the restoration of glutamine pools. In summary, enterally administered OKG, which enhances intestinal adaptation after massive resection and improves muscle glutamine and protein content, could contribute significantly to nutritional management after small bowel resection.

Adaptation, Physiological↗

PubMed2002

"You can't cure it so you have to endure it": the experience of adaptation to diabetic renal disease.

In this study, the experience of adaptation to diabetic renal disease was examined from a phenomenological perspective. Twenty patients attending a diabetic renal clinic were interviewed in depth. Through the use of a template analysis approach, a set of strong themes relating to changes in lifestyle was identified: changes in the nature of involvement with the medical system, coping strategies, and hopes, fears, and expectations. Almost all participants attempted to construct a "good adaptation" in the face of the uncertainties surrounding their condition by adopting a stoic and fatalistic stance. This is discussed in the context of the claim that contemporary society holds emotional self-expression rather than stoical endurance to be the appropriate response to suffering.

Adaptation, Psychological↗

PubMed2002

Immunoneutralization of endogenous glucagon-like peptide-2 reduces adaptive intestinal growth in diabetic rats.

Supraphysiological doses of glucagon-like peptide-2 (GLP-2) have been shown to induce intestinal growth by increasing villus height and crypt depth and by decreasing apoptosis, but a physiological effect of GLP-2 has not yet been demonstrated. Earlier, we found elevated levels of endogenous GLP-2 in untreated streptozotocin diabetic rats associated with marked intestinal growth. In the present study, we investigated the role of endogenous GLP-2 for this adaptive response. We included four groups of six rats: (1) diabetic rats treated with saline, (2) diabetic rats treated with non-specific antibodies, (3) diabetic rats treated with polyclonal GLP-2 antibodies and (4) non-diabetic control rats treated with saline. All animals were treated with once daily intraperitoneal injections for 13 days and killed on day 14. Diabetic rats treated with saline or non-specific antibodies had a significantly (P<0.01) increased area of mucosa (13.00+/-0.64 and 13.37+/-0.60 mm(2), respectively) in the proximal part of the small intestine compared with non-diabetic controls (7.97+/-0.70 mm(2)). In contrast, diabetic rats treated with GLP-2 antibodies had a significantly (P<0.01) smaller increase in area of mucosa in the proximal part of the small intestine (10.84+/-0.44 mm(2)). Antibody treatment had no effect on body weight, blood glucose concentrations and food intake. Thus, blocking of endogenous GLP-2 in a model of adaptive intestinal growth reduces the growth response, providing strong evidence for a physiological growth factor function of GLP-2.

Animals↗

PubMed2005

Creativity: self-perceptions over time.

This study explores creativity and motivation in the second half of life. While many quantitative studies on creativity show decline with advancing age, there is some evidence that creativity may change qualitatively over time. The purpose of this study is to elucidate self-perceived changes in creativity over the life span. The participants included visual artists, both working and retired. A total of 21 adults, ages 53 to 75, participated in the study. Ten of the artists were interviewed in depth regarding the perception of their own creativity over time. Another 11 artists participated in two separate focus groups. All of the participants represented their perceived creativity using an adaptation of the Creative Life-Line Curve (CLLC; Romaniuk, Romaniuk, Sprecher, & Cones, 1983). Findings indicated that participants do not perceive a decline in creativity with age. In-depth analysis of the interviews included qualitative coding to establish a number of themes that permeated the self-perceptions regarding changes in creativity over time. These themes were found to exemplify many of the concepts inherent in the life-span developmental perspective.

Aged↗