No abstract

Expression of the clusterin (CLU) gene results in the synthesis of a conventional secretory isoform set (pre-and mature secretory clusterin proteins, psCLU/sCLU), as well as another set of intracellular isoforms, appearing in the cytoplasm (pre-nuclear CLU, pnCLU) and in the nucleus as an ϳ55-kDa mature nuclear clusterin (nCLU) form. These two isoform sets have opposing cell functions: pro-survival and pro-death, respectively. Although much is known about the regulation and function of sCLU as a pro-survival factor, the regulation and function of endogenous nCLU in cell death are relatively unexplored. Here, we show that depletion of endogenous nCLU protein using siRNA specific to its truncated mRNA increased clonogenic survival of ionizing radiation (IR)-exposed cells. nCLU-mediated apoptosis was Bax-dependent, and lethality correlated with accumulation of mature nCLU protein.

Pierce et al. describe a pediatric patient with a fatal systemic capillary leak syndrome (Clarkson’s disease). They identify a point mutation in p190BRhoGAP and show that patient-derived microvascular endothelial cells show prolonged activation RhoB that correlates with impaired barrier recovery after treatment with TNF compared with control cultures.

Objectives This study aimed to determine whether Ki-67 index evaluated on cytologic material could reliably grade pancreatic neuroendocrine tumors (PanNETs). Methods Cases with adequate cell block and available surgical specimens were included. Ki-67 index was calculated using “eyeballing,” “hot spot,” and “complete” counting methods. Results The overall concordance rates between cytology and surgical specimens were 71%, 73%, and 59%, respectively, by using eyeballing, hot spot, and complete counting approaches. All grade 1 tumors were correctly graded on cytology, but in grade 2 tumors concordance rates were only 36%, 41%, and 9%, respectively. All grade 2 tumors were undergraded when cell blocks contained fewer than 1,000 cells, while concordance rate increased to 57%, 64%, and 14%, respectively, in cases with 1,000 cells or more. Conclusions Grade 2 PanNETs can be significantly undergraded when Ki-67 index is evaluated on cell block material. In cases with 1,000 or more cells, the hot spot counting method has better correlation with surgical specimens.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) results in a variety of clinical symptoms ranging from no or mild to severe disease. Currently, there are multiple postulated mechanisms that may push a moderate to severe disease into a critical state. Human serum contains abundant evidence of the immune status following infection. Cytokines, chemokines, and antibodies can be assayed to determine the extent to which a patient responded to a pathogen. We examined serum and plasma from a cohort of patients infected with SARS-CoV-2 early in the pandemic and compared them to negative-control sera. Cytokine and chemokine concentrations varied depending on the severity of infection, and antibody responses were significantly increased in severe cases compared to mild to moderate infections. Neutralization data revealed that patients with high titers against an early 2020 SARS-CoV-2 isolate had detectable but limited neutralizing antibodies against the emerging SARS-CoV-2 Alpha, Beta and Delta variants. This study highlights the potential of re-infection for recovered COVID-19 patients.

From the onset of the COVID-19 pandemic, the demand for SARS-CoV-2 testing has resulted in an explosion of analytical tests with very different approaches and designs. The variability in testing modalities, compounded by the lack of available commercial reference materials for standardization early in the pandemic, has led to several challenges regarding data harmonization for viral quantitation.

Introduction/Objective The initial months of the SARS-CoV-2 pandemic entailed unprecedented changes to the way lives are lived worldwide, resulting in new means of social and economic engagement. For instance, stay-at-home orders led to youths (and staff) attending school virtually. Likewise, entire sectors of the workforce were blocked from their offices and jobs went online. The aim of these public health policies was to reduce the transmission of SARS- CoV-2; however, less attention has been given to how these policies have impacted the spread of other communicable illnesses. As such, we hypothesized that stay-at-home orders, in conjunction with increased hygiene surveillance and other public health guidelines, altered the transmission cycles of communicable gastrointestinal parasites. We anticipated that when plotted against time, a decrease in positive cases would occur concomitantly with known periods of lockdown; similarly, an increase in positive cases would follow efforts to re-open society. Methods/Case Report To probe this hypothesis, the laboratory information system was queried for positive and negative cases of Giardia and Cryptosporidium identified within the Indiana University Health System based on the Surve-Vue Signature™ Crypto/Giardia assay (Fisher Healthcare, Waltham, MA). Results (if a Case Study enter NA) Results were categorized by patient age: 0 to 18-years-old and 19-110-years-old. Initial review of the pediatric data set reflected that pandemic-related public health measures did not meaningfully alter the incidence of positive test results for these two parasites, though notable observations suggested patterns buried more deeply within the data. Conclusion The findings of this study have broad implications regarding the perceived and actual communicability of Giardia and Cryptosporidium (as well as other gastrointestinal parasites) in both normal and pandemic-times.

After tick transmission, the spirochete, Borrelia burgdorferi (Bb), remains at the skin inoculation site for up to 48 hours before spreading and causing Lyme disease. Bb surface agonists should elicit potent inflammation and clearance in skin. However, the ID50 is <50 Bb, indicating efficient immunoevasion and suggesting that traditional in vitro models are inadequate for accurately characterizing Bb pathogenesis (i.e. most models display efficient Bb clearance by phagocytes). Thus, we have devised a confocal microscopy method for visualizing infectious fluorescent Bb in situ and in real-time. Here, we inject Bb into ear skin of anesthetized mice and collect four-dimensional data regarding Bb motility during natural infection. This data is complemented by quantitative PCR and histological analyses of the temporal fall and rise of spirochete numbers in vivo. By 4h, the majority of Bb at the injection site are immobile, while Bb adjacent to the site are highly motile. Two movement types are seen: 1) a back and forth shift that may aid Bb in finding an optimal migration path and 2) a directed run that navigates dermal structures. Analysis indicates an average Bb velocity of ≥100 um per minute in skin, which is >10x faster than any immune cell velocities observed in our model. This suggests that Bb motility is a primary mechanism for host cell evasion and indicates our imaging techniques will allow true delineation of host-Bb interactions critical for Lyme disease development.