Scanning Electron Microscopic Observation of Dark Cells After Streptomycin Perfusion of the Vestibule in Guinea Pigs

Hearing has been stabilized in the majority of patients studied in the treatment of Meniere\u27s disease with streptomycin. This observation suggests that effects of streptomycin may ameliorate endolymphatic hydrops, possibly by attenuating the activity of secretory tissue. The purpose of this study is to observe the dark cells of the utricle in guinea pigs after streptomycin perfusion of the vestibule. Twelve pigmented guinea pigs weighing 250-350 grams were used in this study. The vestibules in five guinea pigs were perfused monolaterally with 150 μg of streptomycin in artificial perilymph and, in seven, the vestibules were perfused only with artificial perilymph as a control group.Specimens were processed for observation with a scanning electron microscope. After streptomycin perfusion, the margin of the dark cells became indistinct. The luminal surface of the cells bulged out like a dome. The microvilli decreased or were absent, and some debris was deposited on the surface. In four of the five animals, the luminal membrane of the dark cell ruptured. The cytoplasm and organelle extruded into the endolymphatic space. After the cellular debris moved out into the endolymph, either a vanished cell or a nucleus in an empty nest was observed. These cells appeared damaged and destroyed. The results indicate that the dark cells in the membranous wall of the utricle were affected by streptomycin. The results lead to the assumption that streptomycin may reduce the volume of endolymph by damaging the dark cells of the utricle

The Institute of Archaeology & Siegfried H. Horn Museum Newsletter Volume 41.1

William Shea Dies, Karen Shea, Rebecca Shea Erdelyi, Gerhard Pfandl, and Paul J. Ray, Jr. Al-Maktába: The Bookstore Random Surveyhttps://digitalcommons.andrews.edu/iaham-news/1081/thumbnail.jp

Human melanomas and ovarian cancers overexpressing mechanical barrier molecule genes lack immune signatures and have increased patient mortality risk.

We have identified eight genes whose expression in human melanoma metastases and ovarian cancers is associated with a lack of Th1 immune signatures. They encode molecules with mechanical barrier function in the skin and other normal tissues and include filaggrin (FLG), tumor-associated calcium signal transducer 2 (TACSTD2), and six desmosomal proteins (DST, DSC3, DSP, PPL, PKP3, and JUP). This association has been validated in an independent series of 114 melanoma metastases. In these, DST expression alone is sufficient to identify melanomas without immune signatures, while FLG and the other six putative barrier molecules are overexpressed in a different subset of melanomas lacking immune signatures. Similar associations have been identified in a set of 186 ovarian cancers. RNA-seq data from 471 melanomas and 307 ovarian cancers in the TCGA database further support these findings and also reveal that overexpression of barrier molecules is strongly associated with early patient mortality for melanoma (p = 0.0002) and for ovarian cancer (p < 0.01). Interestingly, this association persists for FLG for melanoma (p = 0.012) and ovarian cancer (p = 0.006), whereas DST overexpression is negatively associated with CD8(+) gene expression, but not with patient survival. Thus, overexpression of FLG or DST identifies two distinct patient populations with low immune cell infiltration in these cancers, but with different prognostic implications for each. These data raise the possibility that molecules with mechanical barrier function in skin and other tissues may be used by cancer cells to protect them from immune cell infiltration and immune-mediated destruction

The what and where of adding channel noise to the Hodgkin-Huxley equations

One of the most celebrated successes in computational biology is the Hodgkin-Huxley framework for modeling electrically active cells. This framework, expressed through a set of differential equations, synthesizes the impact of ionic currents on a cell's voltage -- and the highly nonlinear impact of that voltage back on the currents themselves -- into the rapid push and pull of the action potential. Latter studies confirmed that these cellular dynamics are orchestrated by individual ion channels, whose conformational changes regulate the conductance of each ionic current. Thus, kinetic equations familiar from physical chemistry are the natural setting for describing conductances; for small-to-moderate numbers of channels, these will predict fluctuations in conductances and stochasticity in the resulting action potentials. At first glance, the kinetic equations provide a far more complex (and higher-dimensional) description than the original Hodgkin-Huxley equations. This has prompted more than a decade of efforts to capture channel fluctuations with noise terms added to the Hodgkin-Huxley equations. Many of these approaches, while intuitively appealing, produce quantitative errors when compared to kinetic equations; others, as only very recently demonstrated, are both accurate and relatively simple. We review what works, what doesn't, and why, seeking to build a bridge to well-established results for the deterministic Hodgkin-Huxley equations. As such, we hope that this review will speed emerging studies of how channel noise modulates electrophysiological dynamics and function. We supply user-friendly Matlab simulation code of these stochastic versions of the Hodgkin-Huxley equations on the ModelDB website (accession number 138950) and http://www.amath.washington.edu/~etsb/tutorials.html.Comment: 14 pages, 3 figures, review articl

Review for the generalist: evaluation of anterior knee pain

Anterior knee pain is common in children and adolescents. Evaluation and management is challenging and requires a thorough history and physical exam, and understanding of the pediatric skeleton. This article will review common causes of chronic anterior knee pain in the pediatric population with a focus on patellofemoral pain

Associations of Acculturation and Socioeconomic Status With Subclinical Cardiovascular Disease in the Multi-Ethnic Study of Atherosclerosis

http://deepblue.lib.umich.edu/bitstream/2027.42/61254/1/1963.htmhttp://deepblue.lib.umich.edu/bitstream/2027.42/61254/4/Lutsey_DiezRoux_Associationsofacculturationandsocioeconomicsubclinicalcardiovasculardisease2008.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/61254/5/Lutsey_DiezRoux_Associationsofacculturationandsocioeconomicsubclinicalcardiovasculardisease2008.pd

Evidence maps and evidence gaps: evidence review mapping as a method for collating and appraising evidence reviews to inform research and policy

Evidence reviews are a key mechanism for incorporating extensive, complex and specialised evidence into policy and practice, and in guiding future research. However, evidence reviews vary in scope and methodological rigour, creating several risks for decision-makers: decisions may be informed by less reliable reviews; apparently conflicting interpretations of evidence may obfuscate decisions; and low quality reviews may create the perception that a topic has been adequately addressed, deterring new syntheses (cryptic evidence gaps). We present a new approach, evidence review mapping, designed to produce a visual representation and critical assessment of the review landscape for a particular environmental topic or question. By systematically selecting and describing the scope and rigour of each review, this helps guide non-specialists to the most relevant and methodologically reliable reviews. The map can also direct future research through the identification of evidence gaps (whether cryptic or otherwise) and redundancy (multiple reviews on similar questions). We consider evidence review mapping a complementary approach to systematic reviews and systematic maps of primary literature and an important tool for facilitating evidence-based decision-making and research efficiency