[Making innovation in teaching measurable : Psychometric validation of the "Radio-Prak": a questionnaire using the example of a clinical practical seminar in interventional radiology]. / Innovationen in der Lehre messbar machen : Psychometrische Validierung des Messinstrumentes "Radio-Prak" am Beispiel eines klinisch-praktischen Seminars der interventionellen Radiologie.

BACKGROUND: As part of the reform of medical education with a stronger focus on clinical-practical skills, a restructured seminar on interventional radiology was evaluated using a newly developed questionnaire. OBJECTIVES: Because knowledge in medical education is increasingly transferred by means of application-based teaching formats, a suitable evaluation tool is essential to assess the quality of newly implemented teaching courses. The aim of this study was to evaluate the seminar on interventional radiology and to validate the "Radio-Prak" questionnaire psychometrically in the process. MATERIALS AND METHODS: In the summer semester of 2018, 123 students participating in the newly established seminar were asked to document their satisfaction using the "Radio-Prak" questionnaire with 23 items employing a 5-point Likert scale. We evaluated the questionnaire psychometrically by performing exploratory factor (EFA) and reliability analysis and examined differential validity by group differences. RESULTS: The newly structured seminar on interventional radiology was met with great approval by students (mean global rating = 1.31, on a grading scale where 1 = very good, 5 = insufficient). EFA revealed that the questionnaire consisted of two main factors "didactic quality" and "practical quality" (five items each, α = 0.68). The seminar was rated more positively when students perceived the time for practice as sufficient (p < 0.05). Furthermore, female students demonstrated significantly less self-esteem, identified by the item "I have improved my spatial ability through the seminar," (p < 0.05). CONCLUSION: The "Radio-Prak" questionnaire is both reliable and valid as an instrument to evaluate the quality of a clinical-practical seminar. The students assessed the didactic dimension, but also rated the practical component as important in the assessment.

Effect of divalent versus monovalent cations on the MS2 retention capacity of amino-functionalized ceramic filters.

Ceramic capillary membranes conditioned for virus filtration via functionalization with n-(3-trimethoxysilylpropyl)diethylenetriamine (TPDA) are analyzed with respect to their virus retention capacity when using feed solutions based on monovalent and divalent salts (NaCl, MgCl2). The log reduction value (LRV) by operating in dead-end mode using the model bacteriophage MS2 with a diameter of 25 nm and an IEP of 3.9 is as high as 9.6 when using feeds containing MgCl2. In contrast, a lesser LRV of 6.4 is observed for feed solutions based on NaCl. The TPDA functionalized surface is simulated at the atomistic scale using explicit-solvent molecular dynamics in the presence of either Na+ or Mg2+ ions. Computational prediction of the binding free energy reveals that the Mg2+ ions remain preferentially adsorbed at the surface, whereas Na+ ions form a weakly bound dissolved ionic layer. The charge shielding between surface and amino groups by the adsorbed Mg2+ ions leads to an upright orientation of the TPDA molecules as opposed to a more tilted orientation in the presence of Na+ ions. The resulting better accessibility of the TPDA molecules is very likely responsible for the enhanced virus retention capacity using a feed solution with Mg2+ ions.

Cellular uptake of coumarin-6 under microfluidic conditions into HCE-T cells from nanoscale formulations.

UNLABELLED: In vitro studies of ocular bioavailability of active pharmaceutical ingredients (API) from colloidal drug delivery systems do not consider physiological shear stress generated by eyelid wiping and tear flow. The present study introduces a live cell imaging approach which enables the investigation of model drug uptake from various formulations under shear stress by using custom-made microchannels for the cultivation of human corneal epithelial cells (HCE-T). Coumarin-6 (C-6) was used as a model API incorporated into solid lipid nanoparticles and liposomes, and as an aqueous crystalline suspension. Confocal laser scanning microscopy visualized C-6 uptake into HCE-T cells in a time-resolved manner with an applied shear stress of 0.1 Pa. Static conditions were also studied for comparative purposes. Additionally, solid lipid nanoparticles (SLN) were labeled with a fluorescent phospholipid to check whether C-6 uptake was associated with SLN incorporation into the cells. RESULTS: Intact SLN were not incorporated into the cells, i.e., C-6 was passively redistributed from SLN to lipophilic cellular compartments. C-6 was enriched up to a given limit in HCE-T cells within 5 min of contact with the dispersions both under static and under flow conditions. The C-6 delivery rate from liposomes was superior to that from SLN whereby the suspension exhibited the lowest rate. C-6 release rates were comparable for static and flow conditions. Alternate flushing with formulations and buffer revealed that cells accumulated C-6. The results suggest that combining microfluidics with live cell imaging provides a valuable option for in vitro studies of ocular drug delivery.

[Avoidable visual impairment among residents in care institutions: lessons from an intervention project in the Den Bosch region]. / Onnodige slechtziendheid onder ouderen in zorginstellingen: lessen uit een interventieproject in de regio Den Bosch.

INTRODUCTION: Many elderly in care institutions in The Netherlands are visually impaired (visual acuity < 0.3). They fall more frequently, are more depressed and require more care. In this project visually impaired residents were identified and referred for adequate eye care. The aim of this study is to evaluate the intervention, including validation of the screening, assessment of the prevalence and causes of visual impairment as well as the outcome of the treatment. The effectiveness of the care chain is also evaluated. MATERIALS AND METHODS: 640 residents were offered a basic eye examination and 210 of them were referred, via their general practitioner, to an optometrist (10), ophthalmologist (98), or centre for visually impaired persons (1). RESULTS: Compliance in this study was poor. The prevalence of visual impairment (24%) was lower than in comparable studies. Cataract was the main cause in 51%. Overall 17 (8.1%) residents were treated by ophthalmologists and nine (4.3%) were referred to optical shops. Constraints in the care chain are identified. DISCUSSION: Vision screening in care institutions for elderly is feasible and useful. The care chain should be shorter and simpler. That will increase the effectiveness of this intervention, and thereby the quality of life for many residents.

Dermal fibroblasts from acute inflamed atopic dermatitis lesions display increased eotaxin/CCL11 responsiveness to interleukin-4 stimulation.

BACKGROUND: The presence of eosinophils and/or eosinophil-derived products in the dermis is characteristic for involved skin of patients with atopic dermatitis and contributes to the observed tissue injury. CCL11 is a potent chemoattractant and activator of human eosinophils and interleukin (IL)-4 is a potent inducer of CCL11 expression in dermal fibroblasts. OBJECTIVES: As increased fibroblast CCL11 expression may explain eosinophilic infiltration of involved skin areas in atopic dermatitis, we asked whether dermal fibroblasts from atopic patients differ from fibroblasts of healthy individuals in their ability to express CCL11. METHODS: We compared IL-4-induced CCL11 mRNA expression using reverse transcription-polymerase chain reaction from cultured dermal fibroblasts derived from biopsies of chronic lesional and acute lesional atopic skin as well as from skin biopsies derived from normal skin of healthy donors. RESULTS: Considerable variability in IL-4-induced relative CCL11 mRNA expression was detected in fibroblasts derived from biopsies of different individuals. The lowest median IL-4 concentration inducing half maximal CCL11 mRNA expression (EC(50)) was found in fibroblasts derived from acute inflamed atopic lesions. CONCLUSIONS: Inducibility of CCL11 in dermal fibroblasts upon stimulation with Th2 cytokines explains the tissue eosinophilia observed in the presence of Th2 cytokines and the localization of eosinophils to the dermis. Decreased EC(50) values of IL-4-induced CCL11 expression in fibroblasts from acute inflamed atopic skin lesions indicates increased IL-4 responsiveness in these lesions and further substantiates the special role for IL-4-induced dermal fibroblast CCL11 expression in acute lesions. Variable CCL11 expression in fibroblasts from different patients with atopic dermatitis indicates heterogeneity of factors determining atopic phenotype in atopic dermatitis.

Social exclusion decreases prosocial behavior.

In 7 experiments, the authors manipulated social exclusion by telling people that they would end up alone later in life or that other participants had rejected them. Social exclusion caused a substantial reduction in prosocial behavior. Socially excluded people donated less money to a student fund, were unwilling to volunteer for further lab experiments, were less helpful after a mishap, and cooperated less in a mixed-motive game with another student. The results did not vary by cost to the self or by recipient of the help, and results remained significant when the experimenter was unaware of condition. The effect was mediated by feelings of empathy for another person but was not mediated by mood, state self-esteem, belongingness, trust, control, or self-awareness. The implication is that rejection temporarily interferes with emotional responses, thereby impairing the capacity for empathic understanding of others, and as a result, any inclination to help or cooperate with them is undermined.

[A horse with a badly-healing wound? A case report]. / Een paard met een slecht genezende wond? Een case report.

A 14-year-old Haflinger mare was presented with a wound on the right metatarsus which it had sustained 3 years earlier. The wound had never completely healed but had only recently become a problem. Over a period of several months, the wound became larger, produced a lot of exudate, and the horse became lame on the affected limb. Clinical examination and radiographs failed to reveal the cause of the deterioration. Histological evaluation of tissue removed during debridement of the wound revealed squamous cell carcinoma. Because the tumour had already invaded the bone, the prognosis was unfavourable and the horse was euthanised. Necropsy showed the tumour to have metastasised to the right inguinal area and the adjacent mammary gland.

Antiprotease activity in urine of patients with inflammatory skin disorders.

Polymorphonuclear leukocytes contain well-defined proteolytic enzymes in their azurophilic granules that can be released into tissues during inflammation, producing a localized excess of proteases that causes a protease-antiprotease imbalance with subsequent tissue destruction. The antiproteolytic compounds of the epidermis, such as the protease inhibitors elafin and antileukoprotease, are thought to counteract the proteolytic tissue damage. We investigated the urine of patients suffering from inflammatory skin conditions (e.g., erysipelas, psoriasis) for the presence of urinary antiprotease activities. Purification of elastase-inhibitory activities from pooled urine samples by cation exchange high-performance liquid chromatography and preparative and analytical reverse-phase high-performance liquid chromatography yielded two different types of inhibitors. One was a cationic, acid-stable, and elastase-specific inhibitor of M(r) 6,000 by size-exclusion high-performance liquid chromatography. N-terminal amino acid sequence analysis of the first 28 residues showed identity with elafin, an elastase-specific inhibitor recently isolated from psoriatic scales. The second anti-protease activity was due to two forms of urinary bikunin, the inhibitory subunit of inter-alpha-inhibitor. Both bikunin fragments, with M(r) 4,000 and 16,000, were identified by N-terminal amino acid sequence analysis of the first 10 residues and were characterized by an antiproteolytic profile against human leukocyte elastase, cathepsin G, and trypsin. Urinary protease inhibitors may serve as diagnostic markers of inflammatory diseases.

The CXC receptor 2 is overexpressed in psoriatic epidermis.

The CXC chemokines interleukin-8 and GRO/melanoma growth-stimulatory activity (GRO-alpha) are potent activators of neutrophils and lymphocytes, but also stimulate growth and differentiation of nonhematopoietic cells like keratinocytes, fibroblasts, and melanocytes. High mRNA and protein levels have been detected in psoriatic epidermis. Chemokine activation of target cells is mediated by specific receptors and two CXC receptors have been described with similar affinity for interleukin-8 but different affinities for GRO-alpha. In this study, we examined the expression of both CXCR1 and CXCR2 in psoriatic tissue, identifying the target cells of chemokine activation in psoriasis. By immunohistochemistry and in situ hybridization, as confirmed by northern blot analysis and reverse transcriptase polymerase chain reaction, we could detect expression of the CXCR2 in suprabasal lesional psoriatic keratinocytes but not in healthy skin. The CXCR1 could not be localized in psoriatic keratinocytes with immunohistochemistry and in situ hybridization, but infiltrating cells in the dermal compartment expressed both types of receptors. These data suggest that in addition to neutrophil activation by both CXCR1 and CXCR2, activation of keratinocytes mediated by CXCR2 could contribute to the characteristic epidermal changes observed in psoriasis.

Development and function of the early B cell repertoire.

The early B cell repertoire is characterized by extensive interconnectivity, autoreactivity and multispecificity. Our preliminary sequence analysis of some of the idiotype specific antibodies is beginning to provide molecular clues to explain the observed multireactivity and the expression of shared idiotypic determinants on immunoglobulins of early B cells. The VH gene rearrangements analyzed are typical of the early pre-B cell and CD5 B cell repertoire. Some of these include shared or identical CDR3 regions resulting from the use of germline VH, D and JH gene segments in the absence of N region addition. As previously described, the most D proximal VH genes are also used most frequently. Collectively these genetic restrictions, together with the lack of somatic mutation, suggest that the characteristic self reactivity of the early B cell repertoire is related to the expression of germline gene segments and limited use of diversification mechanisms. It has also been possible for the first time to isolate hybridomas secreting functional IgM molecules which use the most D proximal VH gene, VH81X. These antibodies and another example from the VH7183 family have a broad multireactivity pattern possibly because of the presence of an unusually high number of charged amino acid groups present in the VH region. These findings are preliminary and more extensive studies are needed to establish if these groups are responsible for the highly cross-reactive nature of these antibodies. Nevertheless, these unusual characteristics signify a unique role for antibodies expressing this VH gene during B cell development. It is also clear that the observed anti-lymphocyte reactivity, another feature of the newborn repertoire, is the result of the prevalence of B cells using similar if not identical VHDJH genes and DJH joins. The development of these B cells appears to occur consistently in early ontogeny and, again, are not found in conventional splenic B cells obtained from the normal adult. Understanding the functional significance of the early appearance of these antibodies may help to clarify and understand their role during development as well as in autoimmunity. We propose that the unique self reactive nature of the early repertoire provides a pattern within which self-assertiveness develops and results in the establishment of the adult repertoire. In doing so, dominant clones are established which may or may not be within, but whose selection and differentiation is directed by the CD5 B cell subset.(ABSTRACT TRUNCATED AT 400 WORDS)

Appropriate use of the microbiology laboratory in the diagnosis of infectious diseases.

The collection and processing of clinical specimens in the diagnosis of infectious diseases is reviewed. Available culture methods, other laboratory tests, and their appropriate use and interpretation are discussed. Particular emphasis is placed on selection of those tests most likely to give a specific diagnosis while avoiding unnecessary laboratory use.

KTP-532 laser tonsillectomy: a comparison with standard technique.

It has been stated that laser excision of oral and oropharyngeal lesions result in less intraoperative blood loss, reduced postoperative pain, and quicker wound healing, but few controlled studies have been done to substantiate these claims. A study was undertaken to examine the benefits of the KTP-532 laser in a group of 31 patients who underwent tonsillectomy. One tonsil was removed with the KTP-532 laser and the other was excised with conventional dissection and snare technique. Patients were not told which tonsil was removed with the laser. Pain, healing, and intraoperative blood loss comparing one side to the other was assessed. On the evening of surgery, 83% of patients selected the side that underwent standard dissection and snare tonsillectomy as the most painful. By midweek, however, approximately equal numbers of patients selected the laser side as the most painful. At the end of 1 week, 63% of patients felt more pain on the laser dissection side. Possible reasons for these results are discussed. Intraoperative blood loss was significantly reduced with the use of the KTP-532 laser, but healing was not accelerated.

Tympanic membrane perforation in survivors of a SCUD missile explosion.

On February 25, 1990, an Iraqi SCUD missile exploded inside a building housing United States military personnel in Dhahran, Kingdom of Saudi Arabia. One hundred seventy-two individuals who were near the impact site at the time of the blast were interviewed and examined to determine blast injury to the ear. Tympanic membrane (TM) perforation was used as the clinical marker for aural blast injury. Thirty-four personnel had unilateral TM perforation and 28 had bilateral TM perforation. Eighty-six sustained sufficient injury to be hospitalized. Fifty-nine of hospitalized personnel (70%) had TM perforation. Of a total of 90 TM perforations, 39% were estimated to be 25% or less of the tympanic membrane surface area, 36% were 26% to 50%, 16% were 51% to 75%, and 10% were greater than 75%. Morphology of the perforations and estimated proximity to the blast were documented. Personnel distant from the blast, in open doorways or wearing headphones, had relative protection from TM perforation. Historic nuclear blast data were used to estimate the SCUD blast waveform based on measurements of the SCUD impact crater. A mathematical model based on the estimated waveform was validated against the actual field data by comparing the proximity and incidence of TM perforations in the SCUD missile explosion.

Radiographic diagnosis of tibial dyschondroplasia in broilers: a field selection technique.

A technique for early detection of tibial dyschondroplasia (TD) in live broilers was developed using the Lixiscope, a hand-held, real-time skeletal imaging device. The Lixiscope utilizes 125I gamma energy (27 keV), which is converted to electrons and then to visible energy, for imaging by way of an output phosphor or electron-to-photon conversion. Image amplication is 45,000 to 50,000 times, and image resolution is 4.2 line pairs per millimeter. The left and right tibiotarsi of the parent stock of male broiler breeder chickens were examined at 3, 4, 6, and 8 weeks of age. The images readily allowed for the detection of TD. A scoring system was established to assess severity of TD and was confirmed accurate as correlated with direct radiography and macroscopic examination at necropsy. This technique offers a quick, non-invasive, early detection of TD in broilers. The equipment is portable and can be used in field selection procedures.

Immunohistochemical study of a chondroitin-6-sulfate in growth plates of broiler chickens with high and low genetic predispositions to tibial dyschondroplasia.

The distribution of a chondroitin-6-sulfate (C6S) epitope, which is a biochemical marker of chondrocyte hypertrophy, was studied in the growth plates of two lines of 3-week-old broiler chickens with low and high genetic predispositions to tibial dyschondroplasia (TD). Ultrathin sections of growth plates from both groups were subjected to immunolocalization with monoclonal antibody 3-B-3(-), the epitope of which is increased on proteoglycans made by hypertrophic chondrocytes. Bound antibody was localized with colloidal gold-labeled protein A for observation with an electron microscope. The 3-B-3(-) epitope was localized in pericellular and interterritorial matrix of growth plates of both lines. In the low-TD-incidence birds, the concentration of 3-B-3(-) bound to C6S progressively increased from the proliferative zone to the hypertrophic zone. However, in the high-TD-incidence line, the epitope expression remained at a low level in all zones. The increase of the 3-B-3(-) epitope produced by maturing growth-plate chondrocytes is indicative of changes in the glycosaminoglycan chains of proteoglycans that may be important in the process of matrical calcification. Thus, failure of chondrocytes of the high-TD-incidence line to produce this change in post-translational modification of their proteoglycans could be important in the pathological process.

Treatment of acquired cognitive-communicative deficits in young children.

This article argues that pediatric cognitive rehabilitation is different from rehabilitation for adults; that available theoretical perspectives (Piaget, information processing theory, Luria, and learning theory), are both necessary for and seriously underutilized in planning and conducting pediatric therapy; and that the recognition of such theoretical perspectives would significantly alter clinical pediatric practice. This article then suggests an approach to a theory-based clinical pediatric practice and provides examples.

Blood flow to the corpus cavernosum penis in the bull and goat buck during penile quiescence.

Bulls and bucks were used to study the blood flow into and out of the corpus cavernosum penis (CCP) during the non-erect state of the penis. When contrast medium was injected into the dorsal artery of the penis in a bull cadaver and into surgically implanted catheters of anesthetized bucks, it flowed into the cavernous spaces of the CCP via the penetrating arteries. When contrast medium was injected directly into the CCP of the bull and buck there was no evidence of vascular exits along the body of the penis. The only venous outlets from the CCP were in the crus penis area. In the non-erect penis the vascular pressure within the CCP was 17.8 mm Hg higher in the bull and 8.3 mm Hg higher in the buck at the glans area than the crus area. During the non-erect state of the penis most of the blood flow to the CCP is from the dorsal artery of the penis via the penetrating arteries. The results showed that the pressure gradient provides the means for flow of blood from the glans area toward the base or crus penis area. This flow prevents platelet aggregation and clot formation and provides nutrition to local tissue during the long periods of non-erection.

Angiography of the crus penis in the ram and buck during erection.

Serial angiography was used to determine blood flow patterns to the penis of rams and bucks. Animals were anesthetized and the internal pudendal artery was catheterized so that contrast medium could be injected toward the crus penis area. By comparing vascular patterns of the ram and buck during erection, it was found that flow patterns of the corpus cavernosum penis (CCP) and corpus spongiosum penis (CSP) were similar for both species. Contraction of the ischiocavernosus muscles occluded the arterial inflow and venous outflow to the CCP, making it a closed system during peak erection. However, during erection, the contrast medium continued to flow into the CSP, showing that it is not a closed system. In the vasodilatation phase, the CSP usually filled before and more intensely than did the CCP.

Computed tomographic morphometry of the lumbosacral spine of dogs.

In a 5-year prospective study, computed tomographic (CT) morphometry of the lumbosacral vertebral canal was performed on 42 large-breed dogs (21 controls and 21 dogs with lumbosacral stenosis). Dogs were allotted to 4 groups. Group 1 (n = 13) consisted of cadaver specimens obtained from dogs that died or were euthanatized for reasons unrelated to the spine; group 2 (n = 8) consisted of live dogs with no history of clinical signs related to the spine and with normal neurologic examination findings; group 3 (n = 10) consisted of dogs with surgically confirmed lumbosacral stenosis; and group 4 (n = 11) consisted of dogs with suspected lumbosacral stenosis that were managed conservatively. The CT scans were performed, using 5-mm contiguous slices obtained perpendicular to the vertebral canal, from the midbody of the 5th lumbar vertebra through the caudal endplate of the sacrum (L5-S3). Lumbosacral lordosis was minimized in all dogs by positioning them in dorsal recumbency with the hind limbs flexed. A tuberculin syringe calibration phantom was placed within the scanning field of view, parallel to the axis of the spine. In each dog, 11 CT slice locations within the lumbosacral spine were evaluated. At each slice location, sagittal plane diameter, dorsal plane diameter, and transverse area of the vertebral canal, vertebral body, and calibration phantom were measured, using the CT computer's software programs for distance and area calculation. Window/level settings were constant, and all measurements were made by the same operator (JCJ). Accuracy of calibration phantom CT measurements was 100% for sagittal and dorsal plane diameter and was 85% for transverse area.(ABSTRACT TRUNCATED AT 250 WORDS)