New Views of the Glomerulus: Advanced Microscopy for Advanced Diagnosis

New technologies are ready to revolutionize glomerular imaging and significantly improve or replace immunofluorescence and electron microscopy, which have driven research and diagnosis of glomerular diseases for over 50 years. Advanced forms of transmission and scanning electron microscopy have revealed the detailed spatial relationships of the glomerular basement membrane, podocytes, and endothelial cells. These may be overshadowed by super resolution microscopy (SRM), which combines the advantages of immunofluorescence and electron microscopy, offers high resolution identification of specific molecules, and images large, physiologically relevant volumes of the glomerulus. Rapidity, ease of use and low cost with some types of SRM make them potentially suitable for routine diagnosis. SRM visualizes structures below the classical diffraction limit of conventional light microscopy by adding a time variable to either the illumination of the specimen, or to the fluorescence signal emitted by it. Ensemble techniques vary illumination and include Structured Illumination Microscopy (SIM) and Stimulation Emission Depletion Microscopy (STED). Single molecule localization techniques vary the light emission by fluorescence labels in the specimen, and include Photoactivated Localization Microscopy (PALM) and Stochastic Optical Reconstruction Microscopy (STORM). Technologies such as expansion microscopy and genetic labeling can also create effective super resolution imaging by non-optical, specialized preparation techniques. All technologies require dark field fluorescence and some require computer image analysis and reconstruction. Replicating successful application in other areas of biology, SIM, STED, and STORM have visualized normal and nephrotic disease podocytes, and have confirmed their appearances to be similar to those seen by electron microscopy, but with added new information on cell configuration and protein localization. STORM has also localized podocyte cytoskeleton and adhesion proteins, and glomerular basement membrane proteins at a resolution never before possible. These pioneering efforts show the promise of super resolution microscopy, and lay the groundwork for future study and new diagnostic tools for glomerular diseases

Induction of heat-shock proteins does not prevent renal tubular injury following ischemia

Induction of heat-shock proteins does not prevent renal tubular injury following ischemia. The possible protective effect of heat-shock proteins (HSPs) on ischemic injury to renal cells was assessed in two different experimental models: ischemia-reflow in intact rats and medullary hypoxic injury as seen in the isolated perfused rat kidney. Heat shock was induced by raising the core temperature of rats to 42°C for 15 minutes. Following this, Northern blots showed enhanced gene expression of HSP70, HSP60 and ubiquitin at one hour and reaching a maximum by six hours after heat shock in all regions of the kidney, but most prominently in medulla and papilla. The HSP70 protein in the kidney, estimated by immunohistochemical means, was detectable 24 hours following heat shock and further increased at 48 hours following heat shock. In the first set of experiments, the animals underwent uninephrectomy followed by cross clamping of the remaining renal artery for 40 minutes prior to reflow. Serum creatinine and urea nitrogen rose to 3.15 ± 0.98 and 126.4 ± 62.5 mg/dl at 24 hours. No significant differences were observed at 24, 48 and 72 hours after reflow between these values in control rats and rats pretreated with heat shock 48 hours earlier. Severe morphological damage to proximal tubules of the renal cortex was observed to the same extent in both groups. In a second set of experiments, the right kidney was removed either 24 or 48 hours after heat shock and perfused in isolation for 90 minutes. Functional and morphological parameters were compared with those of isolated perfused kidneys obtained from animals that had not been subjected to heat shock. No difference was observed in the degree or extent of hypoxic injury to the medullary thick ascending limb, characteristically observed in the isolated perfused rat kidney, nor did prior induction of HSPs modify the progressive decline in glomerular filtration rate or fractional reabsorption of glucose seen in perfused kidneys. Fractional reabsorption of sodium was slightly higher in kidneys from rats earlier exposed to heat shock. These results do not support the hypothesis that heat shock proteins prevent ischemic renal injury

Rationalising sequence selection by ligand assemblies in the DNA minor groove : the case for thiazotropsin A

DNA-sequence and structure dependence on the formation of minor groove complexes at 5′-XCTAGY-3′ by the short lexitropsin thiazotropsin A are explored based on NMR spectroscopy, isothermal titration calorimetry (ITC), circular dichroism (CD) and qualitative molecular modeling. The structure and solution behaviour of the complexes are similar whether X = A, T, C or G and Z = T, A, I or C, CCTAGI being thermodynamically the most favoured (ΔG = -11.1 ± 0.1 kcal.mol-1). Binding site selectivity observed by NMR for ACTAGT in the presence of TCTAGA when both accessible sequences are concatenated in a 15-mer DNA duplex construct is consistent with thermodynamic parameters (ΙΔGΙACTAGT > ΙΔGΙTCTAGA) measured separately for the binding sites and with predictions from modeling studies. Steric bulk in the minor groove for Y = G causes unfavourable ligand-DNA interactions reflected in lower Gibbs free energy of binding (ΔG = -8.5 ± 0.01 kcal.mol-1). ITC and CD data establish that thiazotropsin A binds the ODNs with binding constants between 106 and 108 M-1 and reveal that binding is driven enthalpically through hydrogen bond formation and van der Waals interactions. The consequences of these findings are considered with respect to ligand self-association and the energetics responsible for driving DNA recognition by small molecule DNA minor groove binder

Tubular cell and keratinocyte single-cell transcriptomics applied to lupus nephritis reveal type I IFN and fibrosis relevant pathways.

The molecular and cellular processes that lead to renal damage and to the heterogeneity of lupus nephritis (LN) are not well understood. We applied single-cell RNA sequencing (scRNA-seq) to renal biopsies from patients with LN and evaluated skin biopsies as a potential source of diagnostic and prognostic markers of renal disease. Type I interferon (IFN)-response signatures in tubular cells and keratinocytes distinguished patients with LN from healthy control subjects. Moreover, a high IFN-response signature and fibrotic signature in tubular cells were each associated with failure to respond to treatment. Analysis of tubular cells from patients with proliferative, membranous and mixed LN indicated pathways relevant to inflammation and fibrosis, which offer insight into their histologic differences. In summary, we applied scRNA-seq to LN to deconstruct its heterogeneity and identify novel targets for personalized approaches to therapy

The Limits of Responsible Innovation: Exploring Care, Vulnerability and Precision Medicine

Drawing on insights from feminist and Science and Technology Studies writing on care and vulnerability, this paper will critically explore conceptualisations of responsibility, care and vulnerability in relation to contemporary approaches to Responsible Innovation (RI). Drawing on examples of some of the social and ethical challenges of precision medicine, we highlight the on-going, distributed and complex nature of innovation and responsibilities in relation to markets, patient and carer experience and data practices associated with these new technologies to highlight some of the limits of RI. We end by reflecting on the implications of our analysis for the social and ethical challenges of precision medicine and RI more generally

Transient, Isolated Head Tremor in “Unaffected” Individuals: Is Essential Tremor an Even More Prevalent Disease Than We Suppose?

Background: Mild and transient head tremor may sometimes be observed in otherwise tremor-free relatives of essential tremor (ET) cases, although its prevalence is unclear. A diagnostic question is whether this transient, isolated head tremor, often observed as no more than a wobble, is an early manifestation of ET or whether it is a normal finding. A direct comparison with controls is needed.Methods: Two hundred and forty-one first-degree relatives of ET cases (FD-ET) and 77 spousal controls (Co) were enrolled in a study of ET. Each underwent a detailed evaluation that included a tremor history and videotaped neurological examination. None of the enrollees reported tremor, had a prior diagnosis of ET, or had significant tremor on screening spirals. All videotaped examinations were initially reviewed by a movement disorder neurologist blinded to subject type, and among those with head tremor on examination, co-reviewed by two additional movement disorders neurologists.Results: Twenty-six (10.8, 95% Confidence interval [CI] = 7.5–15.3%) of 241 FD-ET vs. 2 (2.6, 95% CI = 0.7–9.0%) of 77 Co had isolated, transient head tremor (odds ratio = 4.54, 95% CI = 1.05–19.57, p = 0.04). No enrollee had significant upper extremity tremor and none met inclusion criteria for ET based on the presence of upper extremity tremor. With one exception, head tremor occurred during or after phonation. It was always transient (generally a single back and forth wobble) and rare (observed briefly on one or two occasions during the videotaped examination) and had a faster frequency, lower amplitude and a different quality than voluntary head shaking.Conclusion: The basis for the observed isolated head tremor is unknown, but it could be an early feature of ET in ET families.Indeed, one-in-ten otherwise unaffected first-degree relatives of ET cases exhibited such tremor. To a far lesser extent it was also observed in “unaffected” controls. In both, it is likely a sign of early, emerging, undiagnosed ET, although follow-up studies are needed to confirm this. If it were ET, it would indicate that the prevalence of ET may be considerably higher than previously suspected

Genomewide Association Studies of LRRK2 Modifiers of Parkinson's Disease.

OBJECTIVE: The aim of this study was to search for genes/variants that modify the effect of LRRK2 mutations in terms of penetrance and age-at-onset of Parkinson's disease. METHODS: We performed the first genomewide association study of penetrance and age-at-onset of Parkinson's disease in LRRK2 mutation carriers (776 cases and 1,103 non-cases at their last evaluation). Cox proportional hazard models and linear mixed models were used to identify modifiers of penetrance and age-at-onset of LRRK2 mutations, respectively. We also investigated whether a polygenic risk score derived from a published genomewide association study of Parkinson's disease was able to explain variability in penetrance and age-at-onset in LRRK2 mutation carriers. RESULTS: A variant located in the intronic region of CORO1C on chromosome 12 (rs77395454; p value = 2.5E-08, beta = 1.27, SE = 0.23, risk allele: C) met genomewide significance for the penetrance model. Co-immunoprecipitation analyses of LRRK2 and CORO1C supported an interaction between these 2 proteins. A region on chromosome 3, within a previously reported linkage peak for Parkinson's disease susceptibility, showed suggestive associations in both models (penetrance top variant: p value = 1.1E-07; age-at-onset top variant: p value = 9.3E-07). A polygenic risk score derived from publicly available Parkinson's disease summary statistics was a significant predictor of penetrance, but not of age-at-onset. INTERPRETATION: This study suggests that variants within or near CORO1C may modify the penetrance of LRRK2 mutations. In addition, common Parkinson's disease associated variants collectively increase the penetrance of LRRK2 mutations. ANN NEUROL 2021;90:82-94

The role of panel studies in research on economic behavior

The analytic and monetary costs and benefits of panel surveys are assessed in light of experiences from the Panel Study of Income Dynamics, an 18-year panel survey on the economic status and behavior of the U.S. population. The analytic benefits of panel are formidable, ranging from description of gross change to various analytic advantages of continous and discrete time modelling. Analytic costs such as the conditioning of responses in subsequent participation or nonresponse bias are possible in panel surveys, but their effects can be minimized with proper data collection procedures and analytic adjustments. Surprisingly, the monetary costs of panel surveys are less than the costs of comparable repeated cross-sectional surveys.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26660/1/0000204.pd

word~river literary review (2013)

wordriver is a literary journal dedicated to the poetry, short fiction, and creative nonfiction of adjunct, part-time and fulltime instructors teaching under a semester or yearly contract in our universities, colleges, and community colleges worldwide. Graduate student teachers who have used up their teaching assistant time and are teaching with adjunct contracts for the remainder of their graduate program are also eligible. We’re looking for work that demonstrates the creativity and craft of adjunct/part-time instructors in English and other disciplines. We reserve first publication rights and onetime anthology publication rights for all work published. We do not accept simultaneous submissions.https://digitalscholarship.unlv.edu/word_river/1004/thumbnail.jp