Rare coexistence of keratinizing squamous metaplasia with xanthogranulomatous pyelonephritis. Report of a case with the role of immunocytochemistry in the differential diagnosis

BACKGROUND: Xanthogranulomatous pyelonephritis (XPN), a rare form ofchronicpyelonephritis, is commonly associated with lithiasis and rarely leads to keratinizing squamous metaplasia. Its manifestations closely mimic those of a renal neoplasm, leading to misdiagnosis of malignancy, often resulting in radical nephrectomy. The role of immunocytochemistry in the preoperative cytologic diagnosis is assessed in the present case report. CASE: A 20-year-old male presented with fever and an enlarging mass in the right renal angle. Ultrasonography revealed a heterogeneous mass in the renal pelvis. Fine needle aspiration cytology was advised to rule out malignancy. Aspiration smears from the mass showed many dissociated cells and clusters of them with abundant vacuolated cytoplasm, vesicular nuclei and prominent nucleoli in some cells. Many desquamated metaplastic squamous cells were also seen. The background was predominantly necrotic, with inflammatory cells. The cytologic possibility of XPN with squamous metaplasia vs. renal cell carcinoma was considered. Immunocytochemical markers, epithelial membrane antigen (EMA) and CD68 (histiocytic marker) were used to determine the nature of the suspicious vacuolated cells; these cells were immunoreactive for CD68 and negative for EMA, thus confirming the cytologic diagnosis of XPN with keratinizing squamous metaplasia. CONCLUSION: The case highlights the presence of metaplastic squamous cells in XPN in smears for the first time. Immunocytochemistry is an essential tool in the preoperative cytologic diagnosis of XPN. The patient can be managed conservatively with antibiotics.     

Biotransformations using plant cells, organ cultures and enzyme systems: current trends and future prospects

Plants are valuable sources of a variety of chemicals including drugs, flavours, pigments and agrochemicals. Some of the biochemical reactions occurring in plant cells are complex and cannot be achieved by synthetic routes. In vitro plant cell and organ cultures and plant enzymes act as suitable biocatalysts to perform these complex reactions. A wide variety of chemical compounds including aromatics, steroids, alkaloids, coumarins and terpenoids can undergo biotransformations using plant cells, organ cultures and enzymes. The biocatalyst-mediated reactions are regiospecific and stereospecific. Reaction types include oxidations, reductions, hydroxylations, methylations, acetylations, isomerizations, glycosylations and esterfications. Genetic manipulation approaches to biotransformation offer great potential to express heterologous genes and to clone and overexpress genes for key enzymes. Biotransformation efficiencies can further be improved using molecular techniques involving site-directed mutagenesis and gene manipulation for substrate specificity.     

Role of Bacterial Communities in the Natural Suppression of Rhizoctonia solani Bare Patch Disease of Wheat (Triticum aestivum L.)

Rhizoctonia bare patch and root rot disease of wheat, caused by Rhizoctonia solani AG-8, develops as distinct patches of stunted plants and limits the yield of direct-seeded (no-till) wheat in the Pacific Northwest of the United States. At the site of a long-term cropping systems study near Ritzville, WA, a decline in Rhizoctonia patch disease was observed over an 11-year period. Bacterial communities from bulk and rhizosphere soil of plants from inside the patches, outside the patches, and recovered patches were analyzed by using pyrosequencing with primers designed for 16S rRNA. Taxa in the class Acidobacteria and the genus Gemmatimonas were found at higher frequencies in the rhizosphere of healthy plants outside the patches than in that of diseased plants from inside the patches. Dyella and Acidobacteria subgroup Gp7 were found at higher frequencies in recovered patches. Chitinophaga, Pedobacter, Oxalobacteriaceae (Duganella and Massilia), and Chyseobacterium were found at higher frequencies in the rhizosphere of diseased plants from inside the patches. For selected taxa, trends were validated by quantitative PCR (qPCR), and observed shifts of frequencies in the rhizosphere over time were duplicated in cycling experiments in the greenhouse that involved successive plantings of wheat in Rhizoctonia-inoculated soil. Chryseobacterium soldanellicola was isolated from the rhizosphere inside the patches and exhibited significant antagonism against R. solani AG-8 in vitro and in greenhouse tests. In conclusion, we identified novel bacterial taxa that respond to conditions affecting bare patch disease symptoms and that may be involved in suppression of Rhizoctonia root rot and bare batch disease.     

Population structure and genetic diversity of Bromus tectorum within the small grain production region of the Pacific Northwest

Bromus tectorum L. is an invasive winter annual grass naturalized across the United States. Numerous studies have investigated B. tectorum population structure and genetics in the context of B. tectorum as an ecological invader of natural areas and rangeland. Despite the wealth of information regarding B. tectorum, previous studies have not focused on, or made comparisons to, B. tectorum as it persists in individual agroecosystems. The objectives of this study were to assess the genetic diversity and structure, the occurrence of generalist and specialist genotypes, and the influence of climate on distribution of B. tectorum sourced exclusively from within small grain production regions of the Pacific Northwest. Genetic diversity of B. tectorum sourced from agronomic fields was found to be similar to what has been observed from other land use histories. Six distinct genetic clusters of B. tectorum were identified, with no evidence to indicate that any of the genetic clusters were better adapted to a particular geographical area or climate within the region. Given the apparent random spatial distribution of B. tectorum genetic clusters at the spatial scale of this analysis, unique genotypes may be well mixed within region, similar to what was reported for other inbreeding weedy grass species.     

Is Content Really King? An Objective Analysis of the Public's Response to Medical Videos on YouTube

Medical educators and patients are turning to YouTube to teach and learn about medical conditions. These videos are from authors whose credibility cannot be verified & are not peer reviewed. As a result, studies that have analyzed the educational content of YouTube have reported dismal results. These studies have been unable to exclude videos created by questionable sources and for non-educational purposes. We hypothesize that medical education YouTube videos, authored by credible sources, are of high educational value and appropriately suited to educate the public. Credible videos about cardiovascular diseases were identified using the Mayo Clinic''s Center for Social Media Health network. Content in each video was assessed by the presence/absence of 7 factors. Each video was also evaluated for understandability using the Suitability Assessment of Materials (SAM). User engagement measurements were obtained for each video. A total of 607 videos (35 hours) were analyzed. Half of all videos contained 3 educational factors: treatment, screening, or prevention. There was no difference between the number of educational factors present & any user engagement measurement (p NS). SAM scores were higher in videos whose content discussed more educational factors (p<0.0001). However, none of the user engagement measurements correlated with higher SAM scores. Videos with greater educational content are more suitable for patient education but unable to engage users more than lower quality videos. It is unclear if the notion “content is king” applies to medical videos authored by credible organizations for the purposes of patient education on YouTube.     

Role of regulatory agencies

In this paper the authors discuss the role of regulation in assuring blood safety. After an overview of the subject by a leading expert, examples are provided of regulatory systems for blood transfusion services in several countries and regions. Additionally, the perspective of WHO is given on the essential role of national regulatory authorities in assuring the quality of national blood programmes.Collectively, the sections of this paper afford an opportunity for readers to make comparisons among different regulatory frameworks and to "benchmark" among the existing systems. Despite many differences in approach, a clear pattern emerges of worldwide efforts to strengthen blood regulatory systems.     

Expression of CNPY2 in Mouse Tissues: Quantification and Localization

Canopy FGF signaling regulator 2 (CNPY2) is a FGF21-modulated protein containing a saposin B-type domain. In vitro studies have shown CNPY2 is able to enhance neurite outgrowth in neurons and stabilize the expression of low density lipoprotein receptor in macrophages and hepatocytes. However, no in vivo data are available on the normal expression of CNPY2 and information is lacking on which cell types express this protein in tissues. To address this, the present study examined CNPY2 expression at the mRNA and protein levels. Quantitative PCR and ELISA examination of mouse tissues showed that CNPY2 varies between organs, with the highest expression in the heart, lung and liver. Immunohistochemistry detected CNPY2 in a variety of cell types including skeletal, cardiac and smooth muscle myocytes, endothelial cells and epithelial cells. CNPY2 was also detectable in mouse blood and human and mouse uteri. These data demonstrate CNPY2 is widely distributed in tissues and suggest the protein has biological functions that have yet to be identified. Using these new observations we discuss possible functions of the protein.     

Oligodendrocytes regulate formation of nodes of Ranvier via the recognition molecule OMgp

The molecular mechanisms underlying the involvement of oligodendrocytes in formation of the nodes of Ranvier (NORs) remain poorly understood. Here we show that oligodendrocyte-myelin glycoprotein (OMgp) aggregates specifically at NORs. Nodal location of OMgp does not occur along demyelinated axons of either Shiverer or proteolipid protein (PLP) transgenic mice. Over-expression of OMgp in OLN-93 cells facilitates process outgrowth. In transgenic mice in which expression of OMgp is down-regulated, myelin thickness declines, and lateral oligodendrocyte loops at the node-paranode junction are less compacted and even join together with the opposite loops, which leads to shortened nodal gaps. Notably, each of these structural abnormalities plus modest down-regulation of expression of Na(+) channel alpha subunit result in reduced conduction velocity in the spinal cords of the mutant mice. Thus, OMgp that is derived from glia has distinct roles in regulating nodal formation and function during CNS myelination.     

Left-Handed Intercalated DNA Double Helix: Rendezvous of Ethidium and Actinomycin D in the Z-Helical Conformation Space

Abstract

It is now very well recognized that the DNA double helix is conformationally pluralistic and that this flexibility is derived from internal motions due to backbone torsions. But what is less apparent is that such internal motions can occur in a correlated fashion and express themselves in a wide variety of structural motifs and phenomena. For example, flexibility inherent in the DNA molecule can lead to a family of Z-DNA, LZ1 and LZ2 being the two extremes and correlated internal motion can cause LZ1?LZ2 transition. More interestingly, such motions manifest themselves as breathing modes on the DNA lattice resulting in the sequence specific intercalation sites. Following a detailed stereochemical analyses we observed that the intercalation site for ethidium is located at the dCpdG sequence of the intercalated LZ1 helix (LZ1*) while that for actinomycin D is located at the dGpdC sequence of the intercalated LZ2 helix (LZ2*). From the stereochemistry of the drug binding we make experimentally testable predictions which are in fact supported by a few recent experimental studies. These studies also show that a left-handed intercalated B-DNA model is a viable intermediate in the Z to B transition which can hold the drug with binding energy comparable to that of the intercalated right-handed B-DNA.