Development of a Camel Kidney Cell Strain and Its Use in Virology

A strain of camel kidney cells was developed and carried in serial passages. The subcultures were slow-growing in the early passages and were composed of heterogeneous cell population. By the 35th passage, the growth rate increased, and more homogeneous cells, mostly of the epithelioid type, were seen. The cell strain was highly susceptible to West Nile, Sindbis, vesicular stomatitis, adeno, and vaccinia viruses, and also was susceptible to herpes simplex, rinderpest, measles, and canine distemper viruses.     

RETRACTED ARTICLE: Ulnar malignant peripheral nerve sheath tumour diagnosis in a mixed-breed dog as a model to study human: histologic,immunohistochemical, and clinicopathologic study

Canine Malignant Peripheral Nerve Sheath Tumors (MPNSTs) are uncommonly reported in the ulnar, since they are underestimated relative to the more common spindle cell tumours of soft tissue. In dogs, MPNST accounts for 27% of nervous system tumours. In man, MPNST represents 5-10% of all soft tissue sarcomas and is often associated with neurofibromatosis type 1 (NF-1).An 8-year-old, 9 kg, female mixed-breed dog with a subcutaneous mass on the upper right side of the ulnar region was presented to the small animal research and teaching hospital of Tehran University. The dog was anorexic with general weakness. The mass (7 × 4 cm) was removed surgically and processed routinely. Microscopically, the mass was composed of highly cellular areas with a homogeneous population of round or spindle cells, high cellular pleomorphism, high mitotic index and various morphologic patterns. Furthermore, spindle cells arranged in densely or loosely sweeping fascicles, interlacing whorls, or storiform patterns together with wavy cytoplasm, nuclear palisades, and round cells were arranged in sheets or cords with a meshwork of intratumoral nerve fibers. In addition, in this case the presence of neoplastic cells within the blood vessels was observed. Immunohistochemically, tumor was positive for vimentin and S-100 protein. The histopathologic features coupled with the S-100 and vimentin immunoreactivity led to a diagnosis of malignant neurofibroma.To the best of our knowledge, primary ulnar MPNST has not been reported in animals. This is the first documentation of an ulnar malignant peripheral nerve sheath tumour in a dog.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1310907815984587

     

Design and simulation of a micro-channel for separating the particles with nearly constant dielectrophoretic force in channel space

One of the common approaches for separating the micro-particles is the utilisation of dielectrophoresis (DEP) force. In the present study, a channel structure is introduced in which the controllable electric field is imposed by the use of various voltages to the parallel electrodes in order to finally move the different particles in two opposite sides of the channel. The simulation results reveal that the channel is characterised by the imposition of nearly constant DEP forces in the whole channel, which is the innovation of this work. The samples used for separation are Latex particles with 216 and 557 nm in diameter.     

Direct evidence for encoding of motion streaks in human visual cortex

Temporal integration in the visual system causes fast-moving objects to generate static, oriented traces (‘motion streaks’), which could be used to help judge direction of motion. While human psychophysics and single-unit studies in non-human primates are consistent with this hypothesis, direct neural evidence from the human cortex is still lacking. First, we provide psychophysical evidence that faster and slower motions are processed by distinct neural mechanisms: faster motion raised human perceptual thresholds for static orientations parallel to the direction of motion, whereas slower motion raised thresholds for orthogonal orientations. We then used functional magnetic resonance imaging to measure brain activity while human observers viewed either fast (‘streaky’) or slow random dot stimuli moving in different directions, or corresponding static-oriented stimuli. We found that local spatial patterns of brain activity in early retinotopic visual cortex reliably distinguished between static orientations. Critically, a multivariate pattern classifier trained on brain activity evoked by these static stimuli could then successfully distinguish the direction of fast (‘streaky’) but not slow motion. Thus, signals encoding static-oriented streak information are present in human early visual cortex when viewing fast motion. These experiments show that motion streaks are present in the human visual system for faster motion.     

Ethyl methanesulfonate treatment of celery plants affects the expression pattern of CEL I endonuclease

CEL I enzyme from celery, as a member of S1 family of nucleases, is known for its high specific activity in recognition and cleavage of base-substitution mismatches on heteroduplex DNA molecules. Despite valuable applications of the enzyme in mutation screening studies, little is known about its function at cellular level. In the present study, we investigated the pattern of CEL I expression in ethyl methanesulfonate (EMS) treated celery plants. An abnormal growth pattern along with wide and clear lesions were observed on the treated plants. A considerable increase in the level of CEL I protein happened in vegetative and generative parts of EMS-treated plants compared with controls. Despite such induction, the enzyme is not expected to be involved in DNA repair during EMS treatment due to the absence of any known nuclear localization signal in the deduced sequence of CEL I protein. Considering the fact that CEL I orthologs are induced during programmed cell death, the high expression of CEL I upon EMS treatment could be due to the stress and necrotic cell death created by the treatment.     

PDGF-dependent regulation of regulator of G protein signaling-5 expression and vascular smooth muscle cell functionality

Regulator of G protein signaling (RGS) proteins, and notably members of the RGS-R4 subfamily, control vasocontractility by accelerating the inactivation of Gα-dependent signaling. RGS5 is the most highly and differently expressed RGS-R4 subfamily member in arterial smooth muscle. Expression of RGS5 first appears in pericytes during development of the afferent vascular tree, suggesting that RGS5 is a good candidate for a regulator of arterial contractility and, perhaps, for determining the mass of the smooth muscle coats required to regulate blood flow in the branches of the arterial tree. Consistent with this hypothesis, using cultured vascular smooth muscle cells (VSMCs), we demonstrate RGS5 overexpression inhibits G protein-coupled receptor (GPCR)-mediated hypertrophic responses. The next objective was to determine which physiological agonists directly control RGS5 expression in VSMCs. GPCR agonists failed to directly regulate RGS5 mRNA expression; however, platelet-derived growth factor (PDGF) acutely represses expression. Downregulation of RGS5 results in the induction of migration and the activation of the GPCR-mediated signaling pathways. This stimulation leads to the activation of mitogen-activated protein kinases directly downstream of receptor stimulation, and ultimately VSMC hypertrophy. These results demonstrate that RGS5 expression is a critical mediator of both VSMC contraction and potentially, arterial remodeling.     

Induction of cytokine formation by human intestinal bacteria in gut epithelial cell lines

Aims: To investigate the effects of human gut micro‐organisms on cytokine production by human intestinal cell lines. Methods and Results: Quantitative real‐time PCR assays were developed to measure the production of pro‐inflammatory (IL‐1α, IL‐6, IL‐18 and TNFα) and anti‐inflammatory (TGF‐β1, TGF‐β2, TGF‐β3, IL‐4 and IL‐10) cytokines in HT‐29 and Caco‐2 cell lines. They were co‐cultured with a range of mucosal bacteria isolated from ulcerative colitis patients, together with lactobacilli and bifidobacteria obtained from healthy people. HT‐29 cells were also co‐cultured with Campylobacter jejuni, enterotoxigenic Escherichia coli (ETEC), enteropathogenic E. coli and Salmonella typhimurium. The majority of commensal bacteria tested suppressed the expression of anti‐inflammatory cytokine mRNA, increased IL‐18, reduced IL‐1α, and with the exception of nonpathogenic E. coli, reduced TNF‐α. All overtly pathogenic species increased both pro‐inflammatory and anti‐inflammatory cytokine mRNA. Conclusion: Commensal and pathogenic species induced fundamentally different cytokine responses in human intestinal epithelial cell lines. Significance and Impact of the Study: Interactions between commensal bacteria tested in this study and the innate immune system were shown to be anti‐inflammatory in nature, in contrast to the pathogenic organisms investigated. These data contribute towards our understanding of how potential probiotic species can be used to suppress the pro‐inflammatory response in inflammatory bowel disease.