205 research outputs found
Multiple Glucagon-Producing Pancreatic Neuroendocrine Tumors in a Horse (Equus caballus)
Pancreatic neuroendocrine tumors of glucagon-producing cells are extremely rare in domestic animals. In this report, we describe for the first time, to our knowledge, the incidental finding of multiple glucagon-producing neuroendocrine tumors of the pancreas of a horse. The animal was euthanized due to severe local infection after tooth extraction. On postmortem examination, multiple white nodules of up to 4 cm in diameter were observed in the pancreas. Histologically, pancreatic nodules had the appearance of neuroendocrine neoplasms with positive immunoreactivity for glucagon, synaptophysin, chromogranin A, and neuron-specific enolase. Electron microscopy revealed numerous electron-dense granules, similar to those observed in normal pancreatic alpha cells, in the neoplastic cells. In addition, the left adrenal gland showed multiple hyperplastic foci and adenomas in the medulla that were identified as pheochromocytomas. Based on the morphologic appearance and immunohistochemical staining pattern of pancreatic nodules, a diagnosis of multiple glucagon-producing neuroendocrine tumors was made
Vitamin D and Its Analogues: From Differences in Molecular Mechanisms to Potential Benefits of Adapted Use in the Treatment of Alzheimer’s Disease
Lifestyle habits and insufficient sunlight exposure lead to a high prevalence of vitamin
D hypovitaminosis, especially in the elderly. Recent studies suggest that in central Europe more
than 50% of people over 60 years are not sufficiently supplied with vitamin D. Since vitamin D
hypovitaminosis is associated with many diseases, such as Alzheimer’s disease (AD), vitamin D
supplementation seems to be particularly useful for this vulnerable age population. Importantly, in
addition to vitamin D, several analogues are known and used for different medical purposes. These
vitamin D analogues differ not only in their pharmacokinetics and binding affinity to the vitamin D
receptor, but also in their potential side effects. Here, we discuss these aspects, especially those of the
commonly used vitamin D analogues alfacalcidol, paricalcitol, doxercalciferol, tacalcitol, calcipotriol,
and eldecalcitol. In addition to their pleiotropic effects on mechanisms relevant to AD, potential
effects of vitamin D analogues on comorbidities common in the context of geriatric diseases are
summarized. AD is defined as a complex neurodegenerative disease of the central nervous system and
is commonly represented in the elderly population. It is usually caused by extracellular accumulation
of amyloidogenic plaques, consisting of amyloid (Aβ) peptides. Furthermore, the formation of
intracellular neurofibrillary tangles involving hyperphosphorylated tau proteins contributes to the
pathology of AD. In conclusion, this review emphasizes the importance of an adequate vitamin D
supply and discusses the specifics of administering various vitamin D analogues compared with
vitamin D in geriatric patients, especially those suffering from AD
Local and systemic inflammation after implantation of a novel iron based porous degradable bone replacement material in sheep model
Despite the high potential of healthy bone to regenerate, the reconstruction of large bone defects remains a challenge. Due to the lack of mechanical stability of existing bone substitutes, recently developed degradable metallic alloys are an interesting alternative providing higher load-bearing capabilities. Degradable iron-based alloys therefore might be an attractive innovation. To test the suitability of a newly-designed iron-based alloy for such applications, an animal experiment was performed. Porous iron-based degradable implants with two different densities and a control group were tested. The implants were positioned in the proximal tibia of Merino sheep. Over a period of 6 and 12~months, blood and histological parameters were monitored for signs of inflammation and degradation. In the histological evaluation of the implants` environment we found degraded alloy particles, but no inflammatory reaction. Iron particles were also found within the popliteal lymph nodes on both sides. The serum blood levels of phosphorus, iron and ferritin in the long term groups were elevated. Other parameters did not show any changes. Iron-based degradable porous bone replacement implants showed a good biocompatibility in this experiment. For a clinical application, however, the rate of degradation would have to be significantly increased. Biocompatibility would then have to be re-evaluated
Interprofessional education: a necessity in Alzheimer’s dementia care—a pilot study
Introduction: Interprofessional collaboration is seen as an indispensable
prerequisite for high-quality health services and patient care, especially for
complex diseases such as dementia. Thus, the current project aimed to extend
interprofessional and competency-based education in the field of dementia care
to the previously understudied therapy professions of nutrition, speech-language
pathology, and physiotherapy.
Methods: A three-day workshop was designed to provide specific learning
objectives related to patient-centered dementia care, as well as competences
for interprofessional collaboration. Teaching and learning approaches included
case-based learning in simulated interprofessional case-conferences and peerteaching. A total of 42 students (n = 20 nutrition therapy and counseling, n = 8
speech-language pathology, n = 14 physiotherapy), ranging from first to seventh
semester, finished the whole workshop and were considered in data analysis.
Changes in self-perceived attitudes toward interprofessional collaboration and
education were measured by the German version of the UWE-IP. An in-house
questionnaire was developed to evaluate knowledge and skills in the field of
dementia, dementia management and interprofessional collaboration.
Results: Participation in the workshop led to significant improvements in the total
scores of the UWE-IP-D and the in-house questionnaire, as well as their respective
subscales. Moderate to large effect sizes were achieved. All professions improved
significantly in both questionnaires with large effect sizes. Significant differences
between professions were found in the UWE-IP-D total score between students of
speech-language pathology and physiotherapy in the posttest. Students of nutrition
therapy and counseling revealed a significant lower level of self-perceived knowledge
and skills in the in-house questionnaire pre- and post-testing.
Discussion: The pilot-study confirms the effectiveness of interprofessional
education to promote generic and interprofessional dementia care competencies
and to develop positive attitudes toward interprofessional learning and
collaboration in the therapy professions, thus increasing professional diversity
in interprofessional education research. Differences between professions were
confounded by heterogenous semester numbers and participation conditions.
To achieve a curricular implementation, interprofessional education should
be expanded to include a larger group of participants belonging to different
professions, start early in the study program, and be evaluated over the long term
Assessment of Local Reaction to Vaccines in Live Piglets with Magnetic Resonance Imaging Compared to Histopathology
The safety of veterinary vaccines is assessed in clinical trials in Europe. The assessment of the local tissue reaction to vaccination by magnetic resonance imaging (MRI) could reduce the number of animals needed because repeated examinations can be performed in the same animal over time. The present study compared the evaluation of local tissue reactions to vaccination using MRI in live pigs with histopathology of porcine tissue, the current gold standard in regulatory safety testing. Eight piglets each were administered one of two commercial vaccines into marked injection sites. All animals were sedated and scanned repeatedly by MRI using a contrast agent up to day 29 after vaccination. On day 29, the animals were euthanized and underwent a pathological examination. The MRI results were compared with the pathomorphological findings at the injection site by regression analysis. The MR images and the pathological examinations yielded matching results concerning the sizes of the affected tissue volumes or areas. The use of MRI for regulatory safety testing can reduce the number of animals needed to 8 per examination group. The volume of a local reaction and its progression over time can be evaluated and documented. If persistent lesions develop a final pathomorphological examination is needed to identify the kind and local distribution of the reaction
Development of a novel biodegradable porous iron-based implant for bone replacement
Bone replacement and osteosynthesis require materials which can at least temporarily bear high mechanical loads. Ideally, these materials would eventually degrade and would be replaced by bone deposited from the host organism. To date several metals, notably iron and iron-based alloys have been identified as suitable materials because they combine high strength at medium corrosion rates. However, currently, these materials do not degrade within an appropriate amount of time. Therefore, the aim of the present study is the development of an iron-based degradable sponge-like (i.e. cellular) implant for bone replacement with biomechanically tailored properties. We used a metal powder sintering approach to manufacture a cylindrical cellular implant which in addition contains phosphor as an alloying element. No corrosion inhibiting effects of phosphorus have been found, the degradation rate was not altered. Implant prototypes were tested in an animal model. Bone reaction was investigated at the bone-implant-interface and inside the cellular spaces of the implant. Newly formed bone was growing into the cellular spaces of the implant after 12 months. Signs of implant degradation were detected but after 12 months, no complete degradation could be observed. In conclusion, iron-based open-porous cellular biomaterials seem promising candidates for the development of self-degrading and high load bearing bone replacement materials
Detection of feline coronavirus spike gene mutations as a tool to diagnose feline infectious peritonitis
Objectives Feline infectious peritonitis (FIP) is an important cause of death in the cat population worldwide. The ante-mortem diagnosis of FIP in clinical cases is still challenging. In cats without effusion, a definitive diagnosis can only be achieved post mortem or with invasive methods. The aim of this study was to evaluate the use of a combined reverse transcriptase nested polymerase chain reaction (RT-nPCR) and sequencing approach in the diagnosis of FIP, detecting mutations at two different nucleotide positions within the spike (S) gene. Methods The study population consisted of 64 cats with confirmed FIP and 63 cats in which FIP was initially suspected due to similar clinical or laboratory signs, but that were definitively diagnosed with another disease. Serum/plasma and/or effusion samples of these cats were examined for feline coronavirus (FCoV) RNA by RT-nPCR and, if positive, PCR products were sequenced for nucleotide transitions within the S gene. Results Specificity of RT-nPCR was 100% in all materials (95% confidence interval [CI] in serum/plasma 83.9-100.0;95% CI in effusion 93.0-100.0). The specificity of the sequencing step could not be determined as none of the cats of the control group tested positive for FCoV RNA. Sensitivity of the 'combined RT-nPCR and sequencing approach' was 6.5% (95% CI 0.8-21.4) in serum/plasma and 65.3% (95% CI 50.4-78.3) in effusion. Conclusions and relevance A positive result is highly indicative of the presence of FIP, but as none of the control cats tested positive by RT-nPCR, it was not possible to confirm that the FCoV mutant described can only be found in cats with FIP. Further studies are necessary to evaluate the usefulness of the sequencing step including FCoV-RNA-positive cats with and without FIP. A negative result cannot be used to exclude the disease, especially when only serum/plasma samples are available
First in vitro isolation of Besnoitia besnoiti from chronically infected cattle in Germany
Besnoitia besnoiti was in vitro isolated during the first recorded outbreak of bovine besnoitiosis in Germany. Molecular characterization of the new isolate, named Bb-GER1, revealed almost 100% identity with other B. besnoiti isolates obtained in Portugal, Spain, Israel or South Africa, when partial sequences of the 18S ribosomal RNA gene, of the internal transcribed spacer 1 and of the 5.8S RNA gene were compared. Cystozoites obtained from skin tissue of one bull were infectious for gamma-interferon knockout (GKO) mice by intraperitoneal (ip) inoculation. Tachyzoites were detected in the peritoneal cavity, spleen, liver and lung of the mice 5 days post-infection. The parasite could be maintained in GKO mice by ip inoculation for at least 5 passages. Peritoneal washings containing tachyzoites were obtained from infected mice and used to infect five cell lines (Vero, MARC-145, NA42/13, BHK21, KH-R). The best growth of tachyzoites was observed in BHK21 cells, but replication occurred to a smaller extent also in MARC-145, NA42/13 and KH-R cells. Subsequent comparative analyses revealed that after direct infection of these cell lines with cystozoites derived from bovine skin, the growth was best in NA42/13 cells. Considerable replication was also observed in the BHK21 and KH-R cell lines. Our observations on the growth characteristics of Bb-GER1 partially contrast those for other isolates. The preferential growth in particular cell lines may be characteristic for particular B. besnoiti isolates. A potential association between growth proper-ties and differences in virulence remains to be established. This is the first in vitro isolation of B. besnoiti from cattle in Germany.Laboratorio de Inmunoparasitologí
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