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1.
Eur Spine J ; 33(1): 19-30, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37971536

RESUMEN

PURPOSE: In spine care, frailty is associated with poor outcomes. The aim of this study was to describe changes in frailty in spine care during the coronavirus disease 2019 (COVID-19) pandemic and their relation to surgical management and outcomes. METHODS: Patients hospitalized for spine pathologies between January 1, 2019, and May 17, 2022, within a nationwide network of 76 hospitals in Germany were retrospectively included. Patient frailty, types of surgery, and in-hospital mortality rates were compared between pandemic and pre-pandemic periods. RESULTS: Of the 223,418 included patients with spine pathologies, 151,766 were admitted during the pandemic and 71,652 during corresponding pre-pandemic periods in 2019. During the pandemic, the proportion of high-frailty patients increased from a range of 5.1-6.1% to 6.5-8.8% (p < 0.01), while the proportion of low frailty patients decreased from a range of 70.5-71.4% to 65.5-70.1% (p < 0.01). In most phases of the pandemic, the Elixhauser comorbidity index (ECI) showed larger increases among high compared to low frailty patients (by 0.2-1.8 vs. 0.2-0.8 [p < 0.01]). Changes in rates of spine surgery were associated with frailty, most clearly in rates of spine fusion, showing consistent increases among low frailty patients (by 2.2-2.5%) versus decreases (by 0.3-0.8%) among high-frailty patients (p < 0.02). Changes in rates of in-hospital mortality were not associated with frailty. CONCLUSIONS: During the COVID-19 pandemic, the proportion of high-frailty patients increased among those hospitalized for spine pathologies in Germany. Low frailty was associated with a rise in rates of spine surgery and high frailty with comparably larger increases in rates of comorbidities.


Asunto(s)
COVID-19 , Fragilidad , Humanos , Fragilidad/epidemiología , Fragilidad/complicaciones , Pandemias , Estudios Retrospectivos , Alemania/epidemiología
2.
PLoS Genet ; 17(10): e1009365, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34673769

RESUMEN

Mycoplasmas are minute bacteria controlled by very small genomes ranging from 0.6 to 1.4 Mbp. They encompass several important medical and veterinary pathogens that are often associated with a wide range of chronic diseases. The long persistence of mycoplasma cells in their hosts can exacerbate the spread of antimicrobial resistance observed for many species. However, the nature of the virulence factors driving this phenomenon in mycoplasmas is still unclear. Toxin-antitoxin systems (TA systems) are genetic elements widespread in many bacteria that were historically associated with bacterial persistence. Their presence on mycoplasma genomes has never been carefully assessed, especially for pathogenic species. Here we investigated three candidate TA systems in M. mycoides subsp. capri encoding a (i) novel AAA-ATPase/subtilisin-like serine protease module, (ii) a putative AbiEii/AbiEi pair and (iii) a putative Fic/RelB pair. We sequence analyzed fourteen genomes of M. mycoides subsp. capri and confirmed the presence of at least one TA module in each of them. Interestingly, horizontal gene transfer signatures were also found in several genomic loci containing TA systems for several mycoplasma species. Transcriptomic and proteomic data confirmed differential expression profiles of these TA systems during mycoplasma growth in vitro. While the use of heterologous expression systems based on E. coli and B. subtilis showed clear limitations, the functionality and neutralization capacities of all three candidate TA systems were successfully confirmed using M. capricolum subsp. capricolum as a host. Additionally, M. capricolum subsp. capricolum was used to confirm the presence of functional TA system homologs in mycoplasmas of the Hominis and Pneumoniae phylogenetic groups. Finally, we showed that several of these M. mycoides subsp. capri toxins tested in this study, and particularly the subtilisin-like serine protease, could be used to establish a kill switch in mycoplasmas for industrial applications.


Asunto(s)
Mycoplasma/genética , Mycoplasma/metabolismo , Sistemas Toxina-Antitoxina/genética , Animales , Bacterias/genética , Bacterias/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Cabras/microbiología , Filogenia , Proteómica/métodos , Transcriptoma/genética
3.
Stroke ; 53(4): 1411-1422, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35164533

RESUMEN

Translation of acute ischemic stroke research to the clinical setting remains limited over the last few decades with only one drug, recombinant tissue-type plasminogen activator, successfully completing the path from experimental study to clinical practice. To improve the selection of experimental treatments before testing in clinical studies, the use of large gyrencephalic animal models of acute ischemic stroke has been recommended. Currently, these models include, among others, dogs, swine, sheep, and nonhuman primates that closely emulate aspects of the human setting of brain ischemia and reperfusion. Species-specific characteristics, such as the cerebrovascular architecture or pathophysiology of thrombotic/ischemic processes, significantly influence the suitability of a model to address specific research questions. In this article, we review key characteristics of the main large animal models used in translational studies of acute ischemic stroke, regarding (1) anatomy and physiology of the cerebral vasculature, including brain morphology, coagulation characteristics, and immune function; (2) ischemic stroke modeling, including vessel occlusion approaches, reproducibility of infarct size, procedural complications, and functional outcome assessment; and (3) implementation aspects, including ethics, logistics, and costs. This review specifically aims to facilitate the selection of the appropriate large animal model for studies on acute ischemic stroke, based on specific research questions and large animal model characteristics.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Animales , Isquemia Encefálica/terapia , Modelos Animales de Enfermedad , Perros , Humanos , Reproducibilidad de los Resultados , Ovinos , Porcinos , Activador de Tejido Plasminógeno
4.
Biotechnol Bioeng ; 119(6): 1467-1482, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35211957

RESUMEN

The cyanobacterium Nostoc sp. BB 92.3. had shown antibacterial activity. A cultivation as biofilm, a self-forming matrix of cells and extracellular polymeric substances, increased the antibacterial effect. A new photobioreactor system was developed that allows a surface-associated cultivation of Nostoc sp. as biofilm. High-density polyethylene carriers operated as a moving bed were selected as surface for biomass immobilization. This system, well established in heterotrophic wastewater treatment, was for the first time used for phototrophic biofilms. The aim was a cultivation on a large scale without inhibiting growth while maximizing immobilization. Cultivation in a small photobioreactor (1.5 L) with different volumetric filling degrees of carriers (13.4%-53.8%) in a batch process achieved immobilization rates of 70%-85% and growth was similar to a no-carrier-control. In a larger photobioreactor (65 L) essentially all of the biomass was immobilized on the carriers and the space-time yield of biomass (0.018 gcell dry weight L-1 day- ​​​​​​​1 ) was competitive compared to phototrophic biofilm cultivations from literature. The use of carriers increased the gas exchange in the reactor by a factor of 2.5-3 but doubled the mixing time. Enriched gassing with carbon dioxide resulted in a short-term increase in growth rate, but unexpectedly it also adversely changed the growth morphology.


Asunto(s)
Nostoc , Fotobiorreactores , Antibacterianos , Biopelículas , Biomasa , Fotobiorreactores/microbiología
5.
J Struct Biol ; 213(1): 107680, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33359072

RESUMEN

The tracheobronchial tree is lined by a mucociliary epithelium containing millions of multiciliated cells. Their integrated oscillatory activity continuously propels an overlying pollution-protecting mucus layer in cranial direction, leading to mucociliary clearance - the primary defence mechanism of the airways. Mucociliary transport is commonly thought to co-emerge with the collective ciliary motion pattern under appropriate geometrical and rheological conditions. Proper ciliary alignment is therefore considered essential to establish mucociliary clearance in the respiratory system. Here, we used volume electron microscopy in combination with high-speed reflection contrast microscopy in order to examine ciliary orientation and its spatial organization, as well as to measure the propagation direction of metachronal waves and the direction of mucociliary transport on bovine tracheal epithelia with reference to the tracheal long axis (TLA). Ciliary orientation is measured in terms of the basal body orientation (BBO) and the axonemal orientation (AO), which are commonly considered to coincide, both equivalently indicating the effective stroke as well as the mucociliary transport direction. Our results, however, reveal that only the AO is in line with the mucociliary transport, which was found to run along a left-handed helical trajectory, whereas the BBO was found to be aligned with the TLA. Furthermore, we show that even if ciliary orientation remains consistent between adjacent cells, ciliary orientation exhibits a gradual shift within individual cells. Together with the symplectic beating geometry, this intracellular orientational pattern could provide for the propulsion of highly viscous mucus and likely constitutes a compromise between efficiency and robustness.


Asunto(s)
Cilios/fisiología , Depuración Mucociliar/fisiología , Sistema Respiratorio/anatomía & histología , Animales , Bovinos , Moco/fisiología , Mucosa Respiratoria/anatomía & histología , Mucosa Respiratoria/fisiología
6.
Vet Pathol ; 58(4): 713-729, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33813961

RESUMEN

A comparative study was carried out on common and agile frogs (Rana temporaria and R. dalmatina) naturally infected with ranid herpesvirus 3 (RaHV3) and common toads (Bufo bufo) naturally infected with bufonid herpesvirus 1 (BfHV1) to investigate common pathogenetic pathways and molecular mechanisms based on macroscopic, microscopic, and ultrastructural pathology as well as evaluation of gene expression. Careful examination of the tissue changes, supported by in situ hybridization, at different stages of development in 6 frogs and 14 toads revealed that the skin lesions are likely transient, and part of a tissue cycle necessary for viral replication in the infected hosts. Transcriptomic analysis, carried out on 2 naturally infected and 2 naïve common frogs (Rana temporaria) and 2 naturally infected and 2 naïve common toads (Bufo bufo), revealed altered expression of genes involved in signaling and cell remodeling in diseased animals. Finally, virus transcriptomics revealed that both RaHV3 and BfHV1 had relatively high expression of a putative immunomodulating gene predicted to encode a decoy receptor for tumor necrosis factor in the skin of the infected hosts. Thus, the comparable lesions in infected frogs and toads appear to reflect a concerted epidermal and viral cycle, with presumptive involvement of signaling and gene remodeling host and immunomodulatory viral genes.


Asunto(s)
Infecciones por Herpesviridae , Herpesviridae , Enfermedades de la Piel , Animales , Anuros , Bufonidae , Herpesviridae/genética , Infecciones por Herpesviridae/veterinaria , Enfermedades de la Piel/veterinaria
7.
J Dairy Sci ; 104(8): 9082-9092, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34024610

RESUMEN

Transiently increased teat wall thickness in response to machine milking has been documented by various methods, including ultrasound. However, correlative ultrasonography and histology to detect the origin of this phenomenon is lacking. The first goal of the present study was to evaluate and compare milking-related changes of the teat tissue in 2 breeds of dairy cows (11 Simmental and 3 Holstein) using B-mode ultrasonography. Additionally, the observed changes were compared with ultrasonographic findings in a Holstein cow with periparturient udder edema. Finally, corresponding histological sections of the Simmental teats were analyzed and compared with those from a lactating nonmilked Angus cow. We hypothesized that the mechanical load of both stretching by the vacuum during phases of open teat cup liner and compression by the closed liner during machine milking results in a transient congestion of blood vessels in the teat wall. The barrel of 1 front teat of each cow was scanned immediately before and after machine milking (system vacuum: 42 kPa; pulsation rate: 60 cycles/min; pulsation ratio: 65:35). Shortly after milking (33 ± 6 min), the Simmentals were slaughtered, and their scanned teat was immediately removed and processed for investigation by light microscopy. Ultrasonography after milking revealed anechoic tubular structures mainly in the inner half of the teat wall. Histological examination revealed these structures to be thick-walled veins. The left front and hind teats of the nonmilked lactating cow, collected and prepared identically to those from the Simmental cows, showed the same histological features. Ultrasonographic measurements showed that the diameter of these veins significantly increased after milking compared with matching images before milking. This effect was most pronounced in the Holstein cows. Similarly, these veins were very prominent in the periparturient cow. However, neither the milked cows, including the periparturient cow, nor the lactating nonmilked cow provided any evidence of edematous extravasation on ultrasonography or histology. These findings corroborated our hypothesis that the increase in size of thick-walled veins in the teat tissue is the main reason for the thickening of the teat walls in response to machine milking.


Asunto(s)
Industria Lechera , Glándulas Mamarias Animales , Animales , Bovinos , Femenino , Lactancia , Leche , Pezones
8.
Lasers Med Sci ; 36(4): 855-862, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32813259

RESUMEN

The common limitation of surgical revascularization procedures for severe tissue ischemia due to cardiovascular diseases is the need to interrupt blood flow during the intervention. We aim to introduce a new technique that allows a sutureless, non-occlusive revascularization. A 3-step technique was developed using rabbit's aorta to simulate a side-to-side anastomosis model. It enables the creation of a bypass circuit for revascularization. The first step was the soldering of 2 vessels in a side-to-side fashion based on the laser-assisted vascular anastomosis (LAVA) principle using a diode laser emitting irradiation at 810 nm with an albumin-based solder patch between them, followed by the creation of a channel within the patch using either a holmium-doped yttrium aluminum garnet laser (Ho:YAG) at λ = 2100 nm or a xenon-chloride excimer laser (XeCl) at λ = 308 nm. Thereby, a bypass circuit was created, thus allowing a non-ischemic revascularization. The system was deemed functional when a flow was observed across the anastomosis. The highest average tensile strength recorded after side-to-side LAVA using a diode laser power of 3.2 W for 60 s was 2278.6 ± 800 mN (n = 20). The Ho:YAG laser created the channels with less tension on the anastomosis than the excimer laser. Histological analysis showed limited thermal damage and good patch-tissue adaptation. The preliminary results of this feasibility study outline the foundations for an entirely sutureless laser-assisted revascularization procedure. The next studies will evaluate the rheological parameters across the bypass circuit to optimize the post-anastomotic flow.


Asunto(s)
Anastomosis Quirúrgica/métodos , Láseres de Semiconductores , Animales , Aorta/cirugía , Estudios de Factibilidad , Proyectos Piloto , Conejos , Resistencia a la Tracción
9.
Int J Mol Sci ; 22(4)2021 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-33562136

RESUMEN

Nanoparticle (NP)-assisted procedures including laser tissue soldering (LTS) offer advantages compared to conventional microsuturing, especially in the brain. In this study, effects of polymer-coated silica NPs used in LTS were investigated in human brain endothelial cells (ECs) and blood-brain barrier models. In the co-culture setting with ECs and pericytes, only the cell type directly exposed to NPs displayed a time-dependent internalization. No transfer of NPs between the two cell types was observed. Cell viability was decreased relatively to NP exposure duration and concentration. Protein expression of the nuclear factor ĸ-light-chain-enhancer of activated B cells and various endothelial adhesion molecules indicated no initiation of inflammation or activation of ECs after NP exposure. Differentiation of CD34+ ECs into brain-like ECs co-cultured with pericytes, blood-brain barrier (BBB) characteristics were obtained. The established endothelial layer reduced the passage of integrity tracer molecules. NP exposure did not result in alterations of junctional proteins, BBB formation or its integrity. In a 3-dimensional setup with an endothelial tube formation and tight junctions, barrier formation was not disrupted by the NPs and NPs do not seem to cross the blood-brain barrier. Our findings suggest that these polymer-coated silica NPs do not damage the BBB.


Asunto(s)
Barrera Hematoencefálica/efectos de los fármacos , Revascularización Cerebral/métodos , Células Endoteliales/metabolismo , Nanopartículas/metabolismo , Polímeros/farmacología , Dióxido de Silicio/farmacología , Animales , Linfocitos B/inmunología , Transporte Biológico/fisiología , Barrera Hematoencefálica/fisiología , Encéfalo/irrigación sanguínea , Encéfalo/citología , Encéfalo/metabolismo , Bovinos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Humanos , Terapia por Láser/métodos , Activación de Linfocitos/inmunología , FN-kappa B/metabolismo , Pericitos/metabolismo
10.
Vet Surg ; 50(2): 425-434, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33264429

RESUMEN

OBJECTIVE: To localize vagal branches within the surgical field of laryngoplasty and identify potentially hazardous surgical steps. STUDY DESIGN: Observational cadaveric study. SAMPLE POPULATION: Five equine head-neck specimens and four entire equine cadavers. METHODS: Dissection of the pharyngeal region from a surgical perspective. Neuronal structures were considered at risk if touched or if the distance to instruments was less than 5 mm. RESULTS: The branches of the pharyngeal plexus (PP) supplying the cricopharyngeal muscle (PPcr), the thyropharyngeal muscle (PPth), and the esophagus (PPes) were identified in the surgical field in nine of nine, five of nine, and one of nine specimens, respectively. The internal branch of the cranial laryngeal nerve (ibCLN) was identified within the carotid sheath in six of nine specimens. The external branch of the cranial laryngeal nerve (ebCLN) was identified close to the septum of the caudal constrictors in nine of nine specimens. The blade of the tissue retractor compressed the ibCLN in six of six, the ebCLN in four of six, the PPcr in six of six, the PPth in two of three, and the PPes in two of two specimens in which the respective nerves were identified after further dissection. Surgical exploration of the dorsolateral aspect of the pharynx and the incision of the septum of the caudal constrictors harmed the ebCLN in nine of nine, PPcr in seven of nine, and PPth in four of eight specimens. CONCLUSION: Several vagal branches were located in the surgical field and must be considered at risk because of their location. CLINICAL SIGNIFICANCE: Use of the tissue retractor, dissection over the pharynx, and dissection of the septum of the caudal constrictors involve a risk to damage vagal branches.


Asunto(s)
Caballos/cirugía , Laringoplastia/veterinaria , Traumatismos del Nervio Vago/veterinaria , Animales , Cadáver , Disección/veterinaria , Femenino , Caballos/lesiones , Masculino , Nervio Vago/cirugía , Traumatismos del Nervio Vago/cirugía
11.
Int J Syst Evol Microbiol ; 70(3): 2115-2123, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31999237

RESUMEN

'Treponema phagedenis' was originally described in 1912 by Noguchi but the name was not validly published and no type strain was designated. The taxon was not included in the Approved Lists of Bacterial Names and hence has no standing in nomenclature. Six Treponema strains positive in a 'T. phagedenis' phylogroup-specific PCR test were isolated from digital dermatitis (DD) lesions of cattle and further characterized and compared with the human strain 'T. phagedenis' ATCC 27087. Results of phenotypic and genotypic analyses including API ZYM, VITEK2, MALDI-TOF and electron microscopy, as well as whole genome sequence data, respectively, showed that they form a cluster of species identity. Moreover, this species identity was shared with 'T. phagedenis'-like strains reported in the literature to be regularly isolated from bovine DD. High average nucleotide identity values between the genomes of bovine and human 'T. phagedenis' were observed. Slight genomic as well as phenotypic variations allowed us to differentiate bovine from human isolates, indicating host adaptation. Based on the fact that this species is regularly isolated from bovine DD and that the name is well dispersed in the literature, we propose the species Treponema phagedenis sp. nov., nom. rev. The species can phenotypically and genetically be identified and is clearly separated from other Treponema species. The valid species designation will allow to further explore its role in bovine DD. The type strain for Treponema phagedenis sp. nov., nom. rev. is B43.1T (=DSM 110455T=NCTC 14362T) isolated from a bovine DD lesion in Switzerland.


Asunto(s)
Enfermedades de los Bovinos/microbiología , Dermatitis Digital/microbiología , Filogenia , Treponema/clasificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , Bovinos , ADN Bacteriano/genética , Ácidos Grasos/química , Humanos , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Suiza , Treponema/aislamiento & purificación
12.
Int J Mol Sci ; 21(11)2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32471212

RESUMEN

Small extracellular vesicles (EVs) are among the most frequently investigated EVs and play major roles in intercellular communication by delivering various cargo molecules to target cells. They could potentially represent an alternative delivery strategy to treat ocular toxoplasmosis, a parasitosis affecting the retinal pigment epithelium (RPE). To date, the uptake of human small EVs by RPE cells has never been reported. In this study, we report on the intracellular uptake of fluorescently labelled human urine and fibroblast-derived small EVs by human RPE cells. In summary, both dye-labelled urinary small EVs and small EVs obtained from fibroblasts stably expressing membrane-bound green fluorescent protein were successfully internalized by RPE cells as revealed by immunohistochemistry. In recipient ARPE19 cells, BODIPY-labelled small EVs were found in close vicinity to the parasite Toxoplasma gondii. Additionally, an ultrastructural method was enabled to distinguish between labelled exogenous and endogenous small EVs within target cells.


Asunto(s)
Vesículas Extracelulares/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Transporte Biológico , Células Cultivadas , Vesículas Extracelulares/ultraestructura , Células HEK293 , Humanos , Epitelio Pigmentado de la Retina/ultraestructura
13.
Neuroimage ; 187: 93-103, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29407456

RESUMEN

Stereotaxic systems and automatic tissue segmentation routines enable neuronavigation as well as reproducible processing of neuroimage datasets. Such systems have been developed for humans, non-human-primates, sheep, and rodents, but not for dogs. Although dogs share important neurofunctional and -anatomical features with humans, and in spite of their importance in translational neuroscience, little is known about the variability of the canine brain morphology and, possibly related, function. Moreover, we lack templates, tissue probability maps (TPM), and stereotaxic brain labels for implementation in standard software utilities such as Statistical Parametric Mapping (SPM). Hence, objective and reproducible, image-based investigations are currently impeded in dogs. We have created a detailed stereotaxic reference frame for dogs including TPM and tissue labels, enabling inter-individual and cross-study neuroimage analysis. T2w datasets were acquired from 16 neurologically inconspicuous dogs of different breeds by 3T MRI. The datasets were averaged after initial preprocessing using linear and nonlinear registration algorithms as implemented in SPM8. TPM for gray (GM) and white matter (WM) as well as cerebrospinal fluid (CSF) were created. Different cortical, subcortical, medullary, and CSF regions were manually labeled to create a spatial binary atlas being aligned with the template. A proof-of-concept for automatic determination of morphological and volumetrical characteristics was performed using additional canine datasets (n = 64) including a subgroup of laboratory beagles (n = 24). Overall, 21 brain regions were labeled using the segmented tissue classes of the brain template. The proof-of-concept trial revealed excellent suitability of the created tools for image processing and subsequent analysis. There was high intra-breed variability in frontal lobe and hippocampus volumes, and noticeable inter-breed corpus callosum volume variation. The T2w brain template provides important, breed-averaged canine brain anatomy features in a spatial standard coordinate system. TPM allows automatic tissue segmentation using SPM and enables unbiased automatic image processing or morphological characterization in different canine breeds. The reported volumetric and morphometric results may serve as a starting point for further research aimed at in vivo analysis of canine brain anatomy and function.


Asunto(s)
Encéfalo/anatomía & histología , Encéfalo/diagnóstico por imagen , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Animales , Atlas como Asunto , Perros , Femenino , Masculino , Reproducibilidad de los Resultados , Técnicas Estereotáxicas
14.
Toxicol Appl Pharmacol ; 385: 114800, 2019 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-31678605

RESUMEN

Laser tissue soldering is a novel treatment method for injuries of hollow organs such as cerebrovascular aneurysms. Nanomaterials contained in the solder are foreign to the body. Hence, it is indispensable to carefully examine possible adverse effects prior to introducing this technique. The aim of this study was to characterize the impact of different concentrations of polymer-coated silica nanoparticles (NPs) on mitochondrial function and integrity of brain endothelial cells using the rat brain capillary endothelial cell line rBCEC4. At maximal capacity, NP exposure resulted in a decrease in the oxygen consumption rate whereas glycolysis was not affected. In combination with a stressor, i.e. lack of glucose in the medium, NP exposure interfered primarily with glycolytic ATP generation rather than oxidative phosphorylation. Furthermore, NPs caused a metabolic shift towards a stressed phenotype, exhibiting increased levels of the oxygen consumption rate and the extracellular acidification rate compared to untreated controls. Overall, mitochondrial mass, distribution and morphology as well as intracellular ATP content were not altered. The mitochondrial membrane potential was increased after exposure to the highest NP concentration and the content of proteins involved in mitochondrial dynamics was changed slightly, indicating possible modifications of the fusion / fission balance. In conclusion, PCL-NP exposure changed mitochondrial respiration, especially under glucose deprivation, but did not affect mitochondrial morphology and distribution. Further studies are needed to investigate whether the functional effects are transient or long-term as this will be crucial for the use of these NPs in laser tissue soldering.


Asunto(s)
Encéfalo/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Nanopartículas/toxicidad , Polímeros/toxicidad , Dióxido de Silicio/toxicidad , Adenosina Trifosfato/metabolismo , Animales , Encéfalo/metabolismo , Células Cultivadas , Células Endoteliales/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Consumo de Oxígeno/efectos de los fármacos , Ratas
15.
Vet Res ; 50(1): 10, 2019 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-30736863

RESUMEN

Contagious caprine pleuropneumonia (CCPP), caused by Mycoplasma capricolum subsp. capripneumoniae is a severe disease widespread in Africa and Asia. Limited knowledge is available on the pathogenesis of this organism, mainly due to the lack of a robust in vivo challenge model and the means to do site-directed mutagenesis. This work describes the establishment of a novel caprine challenge model for CCPP that resulted in 100% morbidity using a combination of repeated intranasal spray infection followed by a single transtracheal infection employing the recent Kenyan outbreak strain ILRI181. Diseased animals displayed CCPP-related pathology and the bacteria could subsequently be isolated from pleural exudates and lung tissues in concentrations of up to 109 bacteria per mL as well as in the trachea using immunohistochemistry. Reannotation of the genome sequence of ILRI181 and F38T revealed the existence of genes encoding the complete glycerol uptake and metabolic pathways involved in hydrogen peroxide (H2O2) production in the phylogenetically related pathogen M. mycoides subsp. mycoides. Furthermore, the expression of L-α-glycerophosphate oxidase (GlpO) in vivo was confirmed. In addition, the function of the glycerol metabolism was verified by measurement of production of H2O2 in medium containing physiological serum concentrations of glycerol. Peroxide production could be inhibited with serum from convalescent animals. These results will pave the way for a better understanding of host-pathogen interactions during CCPP and subsequent vaccine development.


Asunto(s)
Enfermedades de las Cabras/fisiopatología , Peróxido de Hidrógeno/metabolismo , Mycoplasma capricolum/fisiología , Pleuroneumonía Contagiosa/fisiopatología , Replicación Viral , Animales , Cabras , Sueros Inmunes/metabolismo , Técnicas In Vitro , Análisis de Secuencia de ADN/veterinaria
16.
BMC Vet Res ; 15(1): 102, 2019 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-30922306

RESUMEN

BACKGROUND: Polymelia is a congenital defect characterized by one or more supernumerary legs. The genetics and aetiology of this condition in cattle have not yet been thoroughly investigated even though several case reports do exist. The model of the nociceptive withdrawal reflex (NWR) has been characterized in several species to study spinal nociceptive processing. It is a polysynaptic spinal reflex that can be elicited by noxious electrical stimulation and recorded by electromyography. Thorough nociceptive examination and preventive analgesic management has not yet been an aspect in the perioperative management of polymelia cases. CASE PRESENTATION: A 4-month-old female Simmental calf was presented with notomelia. The animal was in good health and showed no neurologic deficiencies. Preoperatively, computed tomography was performed to gain more detailed anatomical information. To evaluate the sensitivity of the accessory limb, NWR testing was performed and revealed a connection of the afferent reflex pathway of the accessory limb to the efferent of the normal limb. The accessory limb was surgically removed under general anaesthesia. Intensive care included multimodal pain therapy adapted to the pain intensity scored during regular pain assessment. A gross anatomical dissection as well as a genetic analysis of the accessory limb were performed postoperatively. The calf was identified as a chimera. CONCLUSION: This calf was successfully relieved of its accessory limb. Chimerism has not been described in the congenital defect polymelia. As the accessory limb was pain sensitive and a common nociceptive reflex pathway was identified, thorough perioperative pain management was performed with the intention to prevent chronic neuropathic pain development.


Asunto(s)
Bovinos/anomalías , Deformidades Congénitas de las Extremidades/veterinaria , Analgesia/métodos , Analgesia/veterinaria , Animales , Bovinos/genética , Bovinos/fisiología , Bovinos/cirugía , Electromiografía/veterinaria , Femenino , Deformidades Congénitas de las Extremidades/diagnóstico por imagen , Deformidades Congénitas de las Extremidades/fisiopatología , Deformidades Congénitas de las Extremidades/cirugía , Nocicepción , Dimensión del Dolor/veterinaria , Reflejo , Tomografía Computarizada por Rayos X/veterinaria
17.
J Nanobiotechnology ; 17(1): 46, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30935413

RESUMEN

BACKGROUND: Silica-ε-polycaprolactone-nanoparticles (SiPCL-NPs) represent a promising tool for laser-tissue soldering in the brain. After release of the SiPCL-NPs in the brain, neuronal differentiation might be modulated. The present study was performed to determine effects of SiPCL-NP-exposure at different stages of neuronal differentiation in neuron-like SH-SY5Y cells. The resulting phenotypes were analyzed quantitatively and signaling pathways involved in neuronal differentiation and degeneration were studied. SH-SY5Y cells were differentiated with all-trans retinoic acid or staurosporine to obtain predominantly cholinergic or dopaminergic neurons. The resulting phenotype was analyzed at the end of differentiation with and without the SiPCL-NPs given at various times during differentiation. RESULTS: Exposure to SiPCL-NPs before and during differentiation led to a decreased cell viability of SH-SY5Y cells depending on the differentiation protocol used. SiPCL-NPs co-localized with the neuronal marker ß-3-tubulin but did not alter the morphology of these cells. A significant decrease in the number of tyrosine hydroxylase (TH) immunoreactive neurons was found in staurosporine-differentiated cells when SiPCL-NPs were added at the end of the differentiation. TH-protein expression was also significantly downregulated when SiPCL-NPs were applied in the middle of differentiation. Protein expression of the marker for the dopamine active transporter (DAT) was not affected by SiPCL-NPs. SiPCL-NP-exposure predominantly decreased the expression of the high-affinity choline transporter 1 (CHT1) when the NPs were given before the differentiation. Pathways involved in neuronal differentiation, namely Akt, MAP-K, MAP-2 and the neurodegeneration-related markers ß-catenin and GSK-3ß were not altered by NP-exposure. CONCLUSIONS: The decrease in the number of dopaminergic and cholinergic cells may implicate neuronal dysfunction, but the data do not provide evidence that pathways relevant for differentiation and related to neurodegeneration are impaired.


Asunto(s)
Neuronas Colinérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/efectos de los fármacos , Nanopartículas/toxicidad , Poliésteres/toxicidad , Dióxido de Silicio/toxicidad , Diferenciación Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Neuronas Colinérgicas/citología , Neuronas Colinérgicas/metabolismo , Neuronas Dopaminérgicas/citología , Neuronas Dopaminérgicas/metabolismo , Humanos , Nanopartículas/química , Fenotipo , Poliésteres/química , Transducción de Señal , Dióxido de Silicio/química , Estaurosporina/farmacología , Tretinoina/farmacología
18.
Vet Surg ; 48(8): 1391-1398, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31469435

RESUMEN

OBJECTIVE: To investigate the feasibility and complications associated with ceratohyoidectomy (CHE) in standing sedated horses unaffected (experimental horses) and standing sedated horses affected (clinical cases) with temporohyoid osteoarthropathy (THO). STUDY DESIGN: Case series. ANIMALS: Six experimental horses and four clinical cases. METHODS: Standing CHE was performed in six experimental horses euthanized 30 minutes (n = 3) and 7 days (n = 3) postoperatively. The four clinical cases were presented because of central facial nerve paralysis (n = 3), vestibular ataxia (n = 3), auricular hemorrhage (n = 2), quidding (n = 1), and oesophageal impaction (n = 1). Evolution was assessed by clinical examination during hospitalization and later by telephone interviews for the clinical cases. RESULTS: The procedure was successfully performed in all horses. Experimental horses did not show any short-term postoperative complications. Hemorrhage was experienced intraoperatively in one of the clinical cases and was successfully managed with placement of hemostatic forceps. Vestibular ataxia and other symptoms of THO improved within days, but facial nerve paralysis did not improve until 9 days to 6 months after surgery. Follow-up ranged from 9 to 24 months. All clinical cases returned to performance, and client satisfaction was excellent. CONCLUSION: Ceratohyoidectomy was consistently feasible in standing sedated horses. The method did not result in postoperative complications and led to resolution of clinical signs associated with THO. CLINICAL SIGNIFICANCE: Standing CHE should be considered in horses affected with THO, especially when horses present with marked vestibular deficits and ataxia, to reduce risks associated with recovery from general anesthesia.


Asunto(s)
Sedación Consciente/veterinaria , Enfermedades de los Caballos/cirugía , Animales , Femenino , Caballos , Masculino , Complicaciones Posoperatorias/veterinaria
19.
Artículo en Inglés | MEDLINE | ID: mdl-30181371

RESUMEN

The virus family Flaviviridae encompasses several viruses, including (re)emerging viruses which cause widespread morbidity and mortality throughout the world. Members of this virus family are positive-strand RNA viruses and replicate their genome in close association with reorganized intracellular host cell membrane compartments. This evolutionarily conserved strategy facilitates efficient viral genome replication and contributes to evasion from host cell cytosolic defense mechanisms. We have previously described the identification of a small-compound inhibitor, K22, which exerts a potent antiviral activity against a broad range of coronaviruses by targeting membrane-bound viral RNA replication. To analyze the antiviral spectrum of this inhibitor, we assessed the inhibitory potential of K22 against several members of the Flaviviridae family, including the reemerging Zika virus (ZIKV). We show that ZIKV is strongly affected by K22. Time-of-addition experiments revealed that K22 acts during a postentry phase of the ZIKV life cycle, and combination regimens of K22 together with ribavirin (RBV) or interferon alpha (IFN-α) further increased the extent of viral inhibition. Ultrastructural electron microscopy studies revealed severe alterations of ZIKV-induced intracellular replication compartments upon infection of K22-treated cells. Importantly, the antiviral activity of K22 was demonstrated against several other members of the Flaviviridae family. It is tempting to speculate that K22 exerts its broad antiviral activity against several positive-strand RNA viruses via a similar mechanism and thereby represents an attractive candidate for development as a panviral inhibitor.


Asunto(s)
Antivirales/farmacología , Membrana Celular/efectos de los fármacos , Infecciones por Flaviviridae/tratamiento farmacológico , Flaviviridae/efectos de los fármacos , Aedes , Animales , Línea Celular , Membrana Celular/virología , Chlorocebus aethiops , Infecciones por Flaviviridae/virología , Humanos , Interferón-alfa/farmacología , ARN Viral/genética , Ribavirina/farmacología , Células Vero , Replicación Viral/efectos de los fármacos
20.
J Zoo Wildl Med ; 49(2): 335-344, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29900785

RESUMEN

This study reports the occurrence of the lysosomal storage disease GM2 gangliosidosis (Sandhoff disease) in two 11-mo-old captive-bred, male and female mongoose siblings ( Mungos mungo). The clinical signs and the pathological findings reported here were similar to those reported in other mammalian species. Light microscopy revealed an accumulation of stored material in neurons and macrophages accompanied by a significant neuronal degeneration (swelling of neuronal soma, loss of Nissl substance, and neuronal loss) and gliosis. Electron microscopy of brain tissue identified the stored material as membrane-bound multilamellar bodies. An almost complete lack of total hexosaminidase activity in serum suggested a defect in the HEXB gene (Sandhoff disease in humans). High-performance thin-layer chromatography and mass spectrometry confirmed the accumulation of GM2 ganglioside in brain and kidney tissue, and the lectin staining pattern of the brain tissue further corroborated the diagnosis of a Sandhoff-type lysosomal storage disease.


Asunto(s)
Herpestidae , Enfermedad de Sandhoff/veterinaria , Animales , Animales de Zoológico , Femenino , Masculino , Enfermedad de Sandhoff/diagnóstico , Enfermedad de Sandhoff/patología , Enfermedad de Sandhoff/fisiopatología
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