147 research outputs found
The role of Virus "X" (Tortoise Picornavirus) in kidney disease and shell weakness syndrome in European tortoise species determined by experimental infection
Tortoise Picornavirus (ToPV) commonly known as Virus "X" was recently discovered in juvenile European tortoises suffering from soft carapace and plastron as well as kidney disease. Therefore, this virus was a potential candidate to be a causative agent for these disease patterns. Spur thighed tortoises (Testudo graeca) seemed to be more susceptible to establish clinical symptoms than other European species like T. hermanni. Thus this trial investigated the role of ToPV in the described syndrome. Two groups of juvenile European tortoises (T. graeca and T.hermanni) each of 10 animals, were cloacally, oronasally and intracoelomically inoculated with an infectious dose (~ 2000 TICD) of a ToPV strain isolated from a diseased T. graeca. A control group of two animals of each species received non-infected cell culture supernatant. The tortoises were examined daily and pharyngeal and cloacal swabs for detection of ToPV-RNA by RT-PCR were taken from each animal every six days for a period of 6 months. At the end of the study the remaining animals were euthanised and dissected. Bacteriological and parasitological tests were performed and organ samples of all tortoises were investigated by RT-PCR for the presence of ToPV and histopathology. Animals that were euthanised at the end of the experiment, were examined for presence of specific anti-ToPV antibodies. Several animals in both inoculated groups showed retarded growth and a light shell weakness, in comparison to the control animals. Three animals were euthanised during the trial, showing reduced weight gain, retarded growth, severe shell weakness and apathy, in parallel to clinical observations in naturally infected animals. In all inoculated animals of both species an intermittent virus shedding, starting from 18 days post inoculation (d.p.i.), till 164 d.p.i. was detected, while the control animals remained negative. The virus was successfully reisolated in terrapene heart cell culture in 16 of 20 inoculated animals of both species. Histopathology of most inoculated animals revealed a lack of bone remodeling and vacuolisation in kidney tubuli which supports the described pathogenesis of nephropathy and osteodystrophy. Anti- ToPV antibody titres ranged from 1:2 to >1:256 in 13 of 20 animals, whereas all control animals were seronegative. The study proofed the Henle Koch`s postulates of ToPV as causative agent for shell dystrophy and kidney disease in both testudo species. The proposed species specific sensitivity towards clinical disease was not observed
Besnoitia besnoiti infection alters both endogenous cholesterol de novo synthesis and exogenous LDL uptake in host endothelial cells
Besnoitia besnoiti, an apicomplexan parasite of cattle being considered as emergent in Europe, replicates fast in host endothelial cells during acute infection and is in considerable need for energy, lipids and other building blocks for offspring formation. Apicomplexa are generally considered as defective in cholesterol synthesis and have to scavenge cholesterol from their host cells for successful replication. Therefore, we here analysed the influence of B. besnoiti on host cellular endogenous cholesterol synthesis and on sterol uptake from exogenous sources. GC-MS-based profiling of cholesterol-related sterols revealed enhanced cholesterol synthesis rates in B. besnoiti-infected cells. Accordingly, lovastatin and zaragozic acid treatments diminished tachyzoite production. Moreover, increased lipid droplet contents and enhanced cholesterol esterification was detected and inhibition of the latter significantly blocked parasite proliferation. Furthermore, artificial increase of host cellular lipid droplet disposability boosted parasite proliferation. Interestingly, lectin-like oxidized low density lipoprotein receptor 1 expression was upregulated in infected endothelial hostcells, whilst low density lipoproteins (LDL) receptor was not affected by parasite infection. However, exogenous supplementations with non-modified and acetylated LDL both boosted B. besnoiti proliferation. Overall, current data show that B. besnoiti simultaneously exploits both, endogenous cholesterol biosynthesis and cholesterol uptake from exogenous sources, during asexual replication
Besnoitia besnoiti infection alters both endogenous cholesterol de novo synthesis and exogenous LDL uptake in host endothelial cells
Besnoitia besnoiti, an apicomplexan parasite of cattle being considered as emergent in Europe, replicates fast in host endothelial cells during acute infection and is in considerable need for energy, lipids and other building blocks for offspring formation. Apicomplexa are generally considered as defective in cholesterol synthesis and have to scavenge cholesterol from their host cells for successful replication. Therefore, we here analysed the influence of B. besnoiti on host cellular endogenous cholesterol synthesis and on sterol uptake from exogenous sources. GC-MS-based profiling of cholesterol-related sterols revealed enhanced cholesterol synthesis rates in B. besnoiti-infected cells. Accordingly, lovastatin and zaragozic acid treatments diminished tachyzoite production. Moreover, increased lipid droplet contents and enhanced cholesterol esterification was detected and inhibition of the latter significantly blocked parasite proliferation. Furthermore, artificial increase of host cellular lipid droplet disposability boosted parasite proliferation. Interestingly, lectin-like oxidized low density lipoprotein receptor 1 expression was upregulated in infected endothelial hostcells, whilst low density lipoproteins (LDL) receptor was not affected by parasite infection. However, exogenous supplementations with non-modified and acetylated LDL both boosted B. besnoiti proliferation. Overall, current data show that B. besnoiti simultaneously exploits both, endogenous cholesterol biosynthesis and cholesterol uptake from exogenous sources, during asexual replication
The Relationship between Brachycephalic Head Features in Modern Persian Cats and Dysmorphologies of the Skull and Internal Hydrocephalus
Background: Cat breeders observed a frequent occurrence of internal hydrocephalus in Persian cats with extreme brachycephalic head morphology. Objective: To investigate a possible relationship among the grade of brachycephaly, ventricular dilatation, and skull dysmorphologies in Persian cats. Animals: 92 Persian-, 10 Domestic shorthair cats. Methods: The grade of brachycephaly was determined on skull models based on CT datasets. Cranial measurements were examined with regard to a possible correlation with relative ventricular volume, and cranial capacity. Persians with high (peke-face Persians) and lower grades of brachycephaly (doll-face Persians) were investigated for the presence of skull dysmorphologies.
Results: The mean cranial index of the peke-face Persians (0.97 ± 0.14) was significantly higher than the mean cranial index of doll-face Persians (0.66 ± 0.04; P < 0.001). Peke-face Persians had a lower relative nasal bone length (0.15 ± 0.04) compared to doll-face (0.29 ± 0.08; P < 0.001). The endocranial volume was significantly lower in doll-face than peke-face Persians (89.6 ± 1.27% versus 91.76 ± 2.07%; P < 0.001). The cranial index was significantly correlated with this variable (Spearman´s r: 0.7; P < 0.0001).
Mean ventricle: Brain ratio of the peke-face group (0.159 ± 0.14) was significantly higher compared to doll-face Persians (0.015 ± 0.01; P < 0.001). Conclusion and Clinical Relevance: High grades of brachycephaly are also associated with malformations of the calvarial and facial bones as well as dental malformations. As these dysmorphologies can affect animal welfare, the selection for extreme forms of brachycephaly in Persian cats should be reconsidered
Metabolic Signatures of Cryptosporidium parvum-Infected HCT-8 Cells and Impact of Selected Metabolic Inhibitors on C. parvum Infection under Physioxia and Hyperoxia
Cryptosporidium parvum is an apicomplexan zoonotic parasite recognized as the second leading-cause of diarrhoea-induced mortality in children. In contrast to other apicomplexans, C. parvum has minimalistic metabolic capacities which are almost exclusively based on glycolysis. Consequently, C. parvum is highly dependent on its host cell metabolism. In vivo (within the intestine) infected epithelial host cells are typically exposed to low oxygen pressure (1–11% O2, termed physioxia). Here, we comparatively analyzed the metabolic signatures of C. parvum-infected HCT-8 cells cultured under both, hyperoxia (21% O2), representing the standard oxygen condition used in most experimental settings, and physioxia (5% O2), to be closer to the in vivo situation. The most pronounced effect of C. parvum infection on host cell metabolism was, on one side, an increase in glucose and glutamine uptake, and on the other side, an increase in lactate release. When cultured in a glutamine-deficient medium, C. parvum infection led to a massive increase in glucose consumption and lactate production. Together, these results point to the important role of both glycolysis and glutaminolysis during C. parvum intracellular replication. Referring to obtained metabolic signatures, we targeted glycolysis as well as glutaminolysis in C. parvum-infected host cells by using the inhibitors lonidamine [inhibitor of hexokinase, mitochondrial carrier protein (MCP) and monocarboxylate transporters (MCT) 1, 2, 4], galloflavin (lactate dehydrogenase inhibitor), syrosingopine (MCT1- and MCT4 inhibitor) and compound 968 (glutaminase inhibitor) under hyperoxic and physioxic conditions. In line with metabolic signatures, all inhibitors significantly reduced parasite replication under both oxygen conditions, thereby proving both energy-related metabolic pathways, glycolysis and glutaminolysis, but also lactate export mechanisms via MCTs as pivotal for C. parvum under in vivo physioxic conditions of mammals
Treponema Infection Associated With Genital Ulceration in Wild Baboons
The authors describe genital alterations and detailed histologic findings in
baboons naturally infected with Treponema pallidum. The disease causes
moderate to severe genital ulcerations in a population of olive baboons (Papio
hamadryas anubis) at Lake Manyara National Park in Tanzania. In a field survey
in 2007, 63 individuals of all age classes, both sexes, and different grades
of infection were chemically immobilized and sampled. Histology and molecular
biological tests were used to detect and identify the organism responsible: a
strain similar to T pallidum ssp pertenue, the cause of yaws in humans.
Although treponemal infections are not a new phenomenon in nonhuman primates,
the infection described here appears to be strictly associated with the
anogenital region and results in tissue alterations matching those found in
human syphilis infections (caused by T pallidum ssp pallidum), despite the
causative pathogen’s greater genetic similarity to human yaws-causing strains
Revealing Dissociable Attention Biases in Chronic Smokers Through an Individual-Differences Approach
Addiction is accompanied by attentional biases (AB), wherein drug-related cues grab attention
independently of their perceptual salience. AB have emerged in different flavours depending on
the experimental approach, and their clinical relevance is still debated. In chronic smokers we
sought evidence for dissociable attention abnormalities that may play distinct roles in the clinical
manifestations of the disorder. Fifty smokers performed a modified visual probe-task measuring two
forms of AB and their temporal dynamics, and data on their personality traits and smoking history/
status were collected. Two fully dissociable AB effects were found: A Global effect, reflecting the overall
impact of smoke cues on attention, and a Location-specific effect, indexing the impact of smoke cues
on visuospatial orienting. Importantly, the two effects could be neatly separated from one another
as they: (i) unfolded with dissimilar temporal dynamics, (ii) were accounted for by different sets of
predictors associated with personality traits and smoking history and (iii) were not correlated with one
another. Importantly, the relevance of each of these two components in the single individual depends
on a complex blend of personality traits and smoking habits, a result that future efforts addressing the
clinical relevance of addiction-related AB should take into careful consideration.This study was supported by funding provided by the University of Verona to CDL, CC and L
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