Primary Postnatal Dorsal Root Ganglion Culture from Conventionally Slaughtered Calves.

Neurological disorders in ruminants have an important impact on veterinary health, but very few host-specific in vitro models have been established to study diseases affecting the nervous system. Here we describe a primary neuronal dorsal root ganglia (DRG) culture derived from calves after being conventionally slaughtered for food consumption. The study focuses on the in vitro characterization of bovine DRG cell populations by immunofluorescence analysis. The effects of various growth factors on neuron viability, neurite outgrowth and arborisation were evaluated by morphological analysis. Bovine DRG neurons are able to survive for more than 4 weeks in culture. GF supplementation is not required for neuronal survival and neurite outgrowth. However, exogenously added growth factors promote neurite outgrowth. DRG cultures from regularly slaughtered calves represent a promising and sustainable host specific model for the investigation of pain and neurological diseases in bovines.

Epidemiological, clinical, and diagnostic data on intestinal infections with Entamoeba histolytica and Entamoeba dispar among returning travelers.

BACKGROUND: Among travelers returning from the tropics, Entamoeba spp. are among the most frequently detected intestinal parasites, mainly the presumable apathogenic E. dispar and the pathogenic E. histolytica. METHODS: Among 5,378 travelers seeking diagnosis and treatment for intestinal infections at the travel clinic of the University of Munich between 2005 and 2009, 103 laboratory-confirmed amebiasis cases were detected. The study compares the results of various diagnostic tests among these patients, analyzes data on co-infections and clinical symptoms, and determines the risk for acquiring amebiasis. RESULTS: Initial screening tests (stool microscopy, coproantigen enzyme-linked immunosorbent assay [ELISA]) were positive in 82.5 and 93.9%, respectively. Fecal samples from patients with positive screening test results were subjected to polymerase chain reaction (PCR), which detected E. histolytica in 9.7% and E. dispar in 88.3% of the cases. The majority of E. histolytica cases and more than half of the E. dispar cases had intestinal symptoms typical for amebiasis. In 53.4% of the cases, intestinal co-infections were found, mostly Blastocystis hominis (39.8%), Giardia lamblia (10.7%), Campylobacter spp. (4.9%), and Salmonella typhi (2.9%). The risk for travelers to be infected with E. histolytica or E. dispar was highest for destinations in West Africa, East Africa, and South and South-East Asia. CONCLUSION: Stool microscopy and coproantigen ELISA are appropriate screening tests for intestinal Entamoeba infections among travelers, but intestinal co-infections are common. PCR is highly recommended as the diagnostic method of choice for the differentiation of Entamoeba spp. The presumable apathogenic E. dispar seems to provoke intestinal symptoms.

Controlled study on enteropathogens in travellers returning from the tropics with and without diarrhoea.

Diarrhoea is the most frequent health problem among travellers in the tropics. However, data on the spectrum and relevance of enteropathogens in international travellers with and without diarrhoea are limited. Stool samples from 114 cases of diarrhoea in travellers returning from the tropics were collected for microbiological examination and PCR for norovirus genogroups I and II, enteroaggregative Escherichia coli (EAEC), and enterotoxigenic E. coli (ETEC) producing heat-labile toxin (LT) and heat-stable toxin (ST). Travel and laboratory data of cases were compared with those of 56 travellers without diarrhoea. Among cases, EAEC was found in 45% of stool samples, followed by LT-ETEC (20%), ST-ETEC (16%), Blastocystis hominis (15%), Campylobacter jejuni (12%), norovirus (11%), Giardia lamblia (6%), Shigella spp. (6%), and Salmonella spp., Cryptosporidium spp., and Cyclospora cayetanensis (3% each). However, only for EAEC, ST-ETEC, Blastocystis and Campylobacter was the prevalence significantly higher among cases than among controls. Co-infections were common: 61% for cases and 13% for controls. The most common travel destination was Asia (54%), followed by Africa (35%) and Latin America (9%). The highest relative risk for diarrhoea was calculated for travellers to West Africa, East Africa, and South Asia. In this study, EAEC, LT-ETEC and ST-ETEC were detected most frequently in cases of travellers' diarrhoea. Although enteric infections with EAEC, ST-ETEC and Campylobacter often cause diarrhoea, the pathogenetic relevance remains unclear for most of the other enteropathogens, because of significant prevalence rates also being seen in controls without diarrhoea and the high frequency of co-infections.

Testing alternative ground water models using cross-validation and other methods.

Many methods can be used to test alternative ground water models. Of concern in this work are methods able to (1) rank alternative models (also called model discrimination) and (2) identify observations important to parameter estimates and predictions (equivalent to the purpose served by some types of sensitivity analysis). Some of the measures investigated are computationally efficient; others are computationally demanding. The latter are generally needed to account for model nonlinearity. The efficient model discrimination methods investigated include the information criteria: the corrected Akaike information criterion, Bayesian information criterion, and generalized cross-validation. The efficient sensitivity analysis measures used are dimensionless scaled sensitivity (DSS), composite scaled sensitivity, and parameter correlation coefficient (PCC); the other statistics are DFBETAS, Cook's D, and observation-prediction statistic. Acronyms are explained in the introduction. Cross-validation (CV) is a computationally intensive nonlinear method that is used for both model discrimination and sensitivity analysis. The methods are tested using up to five alternative parsimoniously constructed models of the ground water system of the Maggia Valley in southern Switzerland. The alternative models differ in their representation of hydraulic conductivity. A new method for graphically representing CV and sensitivity analysis results for complex models is presented and used to evaluate the utility of the efficient statistics. The results indicate that for model selection, the information criteria produce similar results at much smaller computational cost than CV. For identifying important observations, the only obviously inferior linear measure is DSS; the poor performance was expected because DSS does not include the effects of parameter correlation and PCC reveals large parameter correlations.

Image recognition: visual grouping, recognition, and learning.

Vision extracts useful information from images. Reconstructing the three-dimensional structure of our environment and recognizing the objects that populate it are among the most important functions of our visual system. Computer vision researchers study the computational principles of vision and aim at designing algorithms that reproduce these functions. Vision is difficult: the same scene may give rise to very different images depending on illumination and viewpoint. Typically, an astronomical number of hypotheses exist that in principle have to be analyzed to infer a correct scene description. Moreover, image information might be extracted at different levels of spatial and logical resolution dependent on the image processing task. Knowledge of the world allows the visual system to limit the amount of ambiguity and to greatly simplify visual computations. We discuss how simple properties of the world are captured by the Gestalt rules of grouping, how the visual system may learn and organize models of objects for recognition, and how one may control the complexity of the description that the visual system computes.

Orientation diffusions.

Diffusions are useful for image processing and computer vision because they provide a convenient way of smoothing noisy data, analyzing images at multiple scales, and enhancing discontinuities. A number of diffusions of image brightness have been defined and studied so far; they may be applied to scalar and vector-valued quantities that are naturally associated with intervals of either the real line, or other flat manifolds. Some quantities of interest in computer vision, and other areas of engineering that deal with images, are defined on curved manifolds;typical examples are orientation and hue that are defined on the circle. Generalizing brightness diffusions to orientation is not straightforward, especially in the case where a discrete implementation is sought. An example of what may go wrong is presented.A method is proposed to define diffusions of orientation-like quantities. First a definition in the continuum is discussed, then a discrete orientation diffusion is proposed. The behavior of such diffusions is explored both analytically and experimentally. It is shown how such orientation diffusions contain a nonlinearity that is reminiscent of edge-process and anisotropic diffusion. A number of open questions are proposed at the end.

Shading and stereo in early perception of shape and reflectance.

Recent experiments involving shaded 2-D stimuli have shown that early-vision mechanisms are capable of interpreting 3-D shape from shading. In particular, target discrimination tasks suggest that a target 'pops out' when background distractors, but not the target, can be interpreted as convex and lit from above or top-left. Since the problem of extracting 3-D shape from shading is intrinsically ill-defined, early vision may need to make these twin assumptions of convexity and top-left lighting in order to constrain the problem. Would these assumptions be recognized as unnecessary and consequently discarded when 3-D shape could be unambiguously defined by some other cue, like stereo disparity? A 2AFC stimulus onset asynchrony paradigm with masking was used in target discrimination experiments. The performance of five naive subjects on tasks where only shading cues were present was compared with that on tasks involving shading as well as stereo cues that define shape unambiguously. The results show that although stereo disparity information is incorporated by early-vision 3-D mechanisms, it is not used to overturn the default assumptions of lighting and shape. Stereo information is interpreted within the framework of top-left lighting, and a consistent preference for convexity is seen over concavity.

Preattentive perception of elementary three-dimensional shapes.

Experiments in which a single target pattern is discriminated from multiple background distractors show that certain shaded, two-dimensional (2-D) stimuli consistent with a top-lit, polyhedral interpretation can be processed fast (< 80 msec) and in parallel. Unshaded line drawings of the same shapes, however, are processed serially. Strong pop-out asymmetries and control experiments involving shaded patterns that do not have familiar 3-D interpretations suggest that such fast, parallel processing is dependent upon perception 3-D shape. Furthermore, this process can be influenced by contextual scene information, in a manner that is dependent upon whether the additional cues contribute to the perception of a consistent 3-D scene.

Early computation of shape and reflectance in the visual system.

A compelling sense of three-dimensional shape may be conveyed by the photograph of an object. Cues such as contour, shading, perspective and occlusion, to name a few, contribute to this percept. Psychophysical experiments suggest that certain aspects of three-dimensional shape are computed rapidly and in parallel by the visual system. Here we report that reflectance is also computed rapidly; moreover, it is the apparent reflectance, rather than brightness or perceptual three-dimensional shape, that is the primary basis for discrimination during the early stages of visual processing.

Acetabular defect classification and surgical reconstruction in revision arthroplasty. A 6-year follow-up evaluation.

From 1982 to 1988, 147 cemented acetabular components were revised with cementless hemispheric press-fit components, with an average follow-up period of 5.7 years (range, 3-9 years). Acetabular defects were typed from 1 to 3 and reconstructed with a bulk or support allograft. Type 1 defects had bone lysis around cement anchor sites and required particulate graft. Type 2A and B defects displayed progressive bone loss superiorly and required particulate graft, femoral head bulk graft, or cup superiorization. Type 2C defects required medial wall repair with wafer femoral head graft. Type 3A and B defects demonstrated progressive amounts of superior rim deficiencies and were treated with structural distal femur or proximal tibia allograft. Six of the 147 components (4.0%), all type 3B, were considered radiographically and clinically unstable, warranting revision. Three of the six were revised. Moderate lateral allograft resorption was noted on radiographs, but host-graft union was confirmed at revision. Size, orientation, and method of fixation of the allografts play an important role in the integrity of structural allografts, while adequate remaining host-bone must be present to ensure bone ingrowth.

Acetabular micromotion as a measure of initial implant stability in primary hip arthroplasty. An in vitro comparison of different methods of initial acetabular component fixation.

Micromotion has been shown to affect bony ingrowth into cementless components. This study was designed both to quantitate initial micromotion at the prosthesis-periacetabular bony interface and to compare different methods of commonly employed acetabular component fixations, ie, a press-fit hemispherical titanium cup, a press-fit hemispherical titanium cup with one and two dome screws, a press-fit titanium hemispherical cup with three spikes, and a cemented chromium-cobalt cup. The press-fit component without screws demonstrated the greatest motion equaling 162 microns at the ilium, 97 microns at the publis, and 54 microns at the ischium. With one and two screws placed into the dome, the mean ileal displacement decreased by 28 microns (17%) and 36 microns (22%), respectively. Dome screw placement demonstrated a minimal effect at the pubis and ischium. Compared to the press-fit component without augmentation, the tri-spike motion was less at the pubis and ischium. The cemented prosthesis provided the least amount of motion in all three areas tested. This experiment demonstrates that the ilium provides the least amount of support to immediate acetabular fixation, while the pubis (anterior column) and ischium (posterior column) provide more stability. One dome screw does not affect the stability of a hemispherical prosthetic cup significantly. A two dome screw fixation provides an added method of support at the ilium, but fails to decrease motion at the pubis or ischium significantly. The tri-spike fixation does not restrict motion at the ilium to the extent as the dome screws, but its effect at the ischium and pubis is much more pronounced. The obvious difference between initial motion seen with cemented versus uncemented components may suggest that before surgery, patients may need a period of protected weight bearing until ingrowth has occurred.

Loading of the contralateral foot in peripheral vascular insufficiency below-knee amputees.

Seven ambulatory peripheral vascular insufficiency below-the-knee amputees underwent gait analysis to determine the local pressures on seven prominent plantar regions in their remaining limb. Patients occupied significantly less stance phase time on their remaining limbs. Peak, mean, and total pressures measured at each of the seven prominent areas was decreased as compared with laboratory age and sex matched controls. The results of this study suggest that the risk of contralateral limb amputation surgery is related to systemic peripheral vascular insufficiency or local factors, and not increased loading of the remaining contralateral "limb-at-risk."

Preattentive texture discrimination with early vision mechanisms.

We present a model of human preattentive texture perception. This model consists of three stages: (1) convolution of the image with a bank of even-symmetric linear filters followed by half-wave rectification to give a set of responses modeling outputs of V1 simple cells, (2) inhibition, localized in space, within and among the neural-response profiles that results in the suppression of weak responses when there are strong responses at the same or nearby locations, and (3) texture-boundary detection by using wide odd-symmetric mechanisms. Our model can predict the salience of texture boundaries in any arbitrary gray-scale image. A computer implementation of this model has been tested on many of the classic stimuli from psychophysical literature. Quantitative predictions of the degree of discriminability of different texture pairs match well with experimental measurements of discriminability in human observers.

Remodeling of the skeletally immature distal radius.

This case report describes the clinical course of a boy 12 years and 11 months old with the skeletal maturity of an 11.5-year-old, with a distal radial fracture that completely remodeled with 36 degrees of radial and 10 degrees of dorsal angulation. As this case demonstrates, the distal forearm may correct angulation in more than one plane. The remodeling capacity depends on the skeletal maturity of the patient, the proximity of the fracture site to the growth plate, the extent of angulation, and the relationship between the plane of angulation and motion of neighboring joints.

Successful revascularization of an occluded renal artery after prolonged anuria.

Renal atherosclerosis and fibromuscular dysplasia are the most common causes of curable human renovascular hypertension and renal failure. Vascular reconstruction often preserves renal function, but renal failure is rarely reversed, especially after days of anuria. We report a case of a 23-year-old woman who as a child underwent a nephrectomy for congenital hydroureter and renal hypoplasia. She later experienced fibromuscular dysplasia of the remaining renal artery, which ultimately progressed to a complete occlusion and 31 days of total anuria. The patient was revascularized, and within 2 months renal function returned with a blood urea nitrogen and creatinine of 9.0 and 1.0 mg/dl, respectively. After a follow-up of 6 months the patient's blood pressure remained 120/80 to 130/80 mm Hg without administration of hypertension medication. In this report we emphasize that under selected circumstances a kidney can survive prolonged ischemia and that delayed revascularization may reestablish renal function.

[The diagnostic and therapeutic validity of pneumoradiography of breast cysts in the light of personal experience with 236 cases]. / Considerazioni sulla validità diagnostica e terapeutica della pneumocistigrafia mammaria alla luce di 236 esperienze personali.

Personal experience of 236 breast cyst aspirations is reported. In 224 cases, insufflation was also successful and pneumocystomammography was carried out, associated always with cytological examination of the aspirated fluid. In 2 cases, the examination made possible a diagnosis of cyst degeneration (0.8%). The number of recurrences was minimal (2.8%). It is concluded that the technique is diagnostically and therapeutically useful.

[Breast pneumocystography. 96 tentative cases]. / La pneumocistigrafia mammaria. Contributo casistico di 96 tentativi.

Successful execution of mammary pneumocystography in 87-96 attempts is reported. A brief description of the method and a statistical assessment of the incidence and features of the cysts observed are followed by the expression of a very favourably judgment on the soundness of the technique, and the presentation of several of the more meaningful cases.

[Our experience in preoperative embolization in kidney neoplasms]. / La nostra esperienza sull'embolizzazione preoperatoria nei tumori renali.

11 cases of preoperative embolization with Spongostan in renal tumours are reported. Contraindications, indications and the by no means negligible advantages which application of this technique offers the surgeon are discussed briefly.

[Facial telethermography in the diagnosis of carotid insufficiency in the extracranial sector]. / La teletermografia facciale nella diagnosi di insufficienza delle carotidi nel tratto extracranico.

The usefulness of facial telethermography in the diagnosis of circulatory insufficiency owing to occlusion of the extracranial vessels is discussed. The method has proved of great assistance in the screening of patients with vascular diseases, and in the choice of a subsequent contrastographic examination. It gave a significant number of positive findings in cases of insufficiency of the internal carotid artery. The number of false positives and false negatives was virtually negligible.