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As the need to better understand the ecology of hotspots of endemism intensifies, the insurance hypothesis is drawing increasing attention from policy-makers and scenario-planners. The hypothesis states that biodiversity increases ecosystem stability. When species numbers fluctuate, there is potential for further perturbation, loss of function and increased opportunity for invasive species to fill vacated niches. Southern Africa is predicted to be disproportionately impacted by global change, and high altitude systems as foci of endemism are particularly vulnerable to warming. Using ants, a group key to ecosystem function, we assess effects of temperature, season, aspect, vegetation and soil conditions on montane ant species richness, stability of ant community composition, and stability of ant species richness across an altitude gradient. Over six consecutive years of bi-annual sampling, we gathered one of the largest standardized data sets to date. We showed for the first time that stability of ant species richness decreases with increasing altitude, whilst compositional similarity of ant communities is higher with increasing altitude. Findings reveal more similar, species-poor, less stable ant communities at high altitude at the same sites over time. Keywords: Ant compositional similarity, Ant species richness, Climate change, Ecological community thresholds, Altitude gradient, Insurance hypothesis

Background: Systemic juvenile idiopathic arthritis (SJIA) is a chronic childhood arthropathy with features of autoinflammation. Early inflammatory SJIA is associated with expansion and activation of neutrophils with a sepsis-like phenotype, but neutrophil phenotypes present in longstanding and clinically inactive disease (CID) are unknown. The objective of this study was to examine activated neutrophil subsets, S100 alarmin release, and gene expression signatures in children with a spectrum of SJIA disease activity.Methods: Highly-purified neutrophils were isolated using a two-step procedure of density-gradient centrifugation followed by magnetic-bead based negative selection prior to flow cytometry or cell culture to quantify S100 protein release. Whole transcriptome gene expression profiles were compared in neutrophils from children with both active SJIA and CID.Results: Patients with SJIA and active systemic features demonstrated a higher proportion of CD16+CD62Llo neutrophil population compared to controls. This neutrophil subset was not seen in patients with CID or patients with active arthritis not exhibiting systemic features. Using imaging flow cytometry, CD16+CD62Llo neutrophils from patients with active SJIA and features of macrophage activation syndrome (MAS) had increased nuclear hypersegmentation compared to CD16+CD62L+ neutrophils. Serum levels of S100A8/A9 and S100A12 were strongly correlated with peripheral blood neutrophil counts. Neutrophils from active SJIA patients did not show enhanced resting S100 protein release; however, regardless of disease activity, neutrophils from SJIA patients did show enhanced S100A8/A9 release upon PMA stimulation compared to control neutrophils. Furthermore, whole transcriptome analysis of highly purified neutrophils from children with active SJIA identified 214 differentially expressed genes (DEG) compared to neutrophils from healthy controls. The most significantly upregulated gene pathway was Immune System Process, including AIM2, IL18RAP, and NLRC4. Interestingly, this gene set showed intermediate levels of expression in neutrophils from patients with long-standing CID yet persistent serum IL-18 elevation. Indeed, all patient samples regardless of disease activity demonstrated elevated inflammatory gene expression, including inflammasome components and S100A8.Conclusion: We identify features of neutrophil activation in SJIA patients with both active disease and CID, including a proinflammatory gene expression signature, reflecting persistent innate immune activation. Taken together, these studies expand understanding of neutrophil function in chronic autoinflammatory disorders such as SJIA.

BackgroundAlthough social rejection is among the strongest proximal precipitants of major depressive disorder (MDD), little is known about the underlying neurobiological mechanisms and whether neural sensitivity to social rejection may help explain differences in MDD risk. To address this issue, we tested whether neural responses to social threat differed in female adolescents at high vs. low maternal risk for MDD.MethodFemale adolescents with (high-risk; n = 22, Mage = 14.68) and without (low-risk; n = 30, Mage = 15.07) a maternal history of depression were experimentally exposed to negative and neutral social evaluation while undergoing an fMRI scan. Neural responses were assessed by event-related activity and functional connectivity, as well as multivoxel pattern analysis. Activity and functional connectivity analyses focused on a priori-selected regions of interest implicated in self-referential processing and emotion regulation.ResultsCompared to low-risk female adolescents, high-risk female adolescents exhibited greater increases in self-reported depression and social disconnection following social evaluation. Moreover, compared to low-risk female adolescents, high-risk female adolescents exhibited greater amygdala responses to negative social evaluation and a differential pattern of functional connectivity in brain regions related to emotion regulation, self-referential processing, and negative affect. Additionally, these markers of neural threat reactivity were related to depressive symptoms.LimitationsA cross-sectional study design and relatively small, Western sample.ConclusionsThese results suggest that exaggerated neural reactivity to social threat-and an atypical pattern of related functional connectivity-is evident in individuals with a preclinical risk factor for depression. Targeting such responding may thus be a fruitful strategy for preventing depression in at-risk youth.

The ability to maintain functional independence throughout the lifespan may be diminished among medically compromised and chronically stressed populations. People living with HIV are more likely to demonstrate functional impairment and report greater exposure to lifetime and chronic stressors than their seronegative counterparts. It is well-known that exposure to stressors and adversity is associated with functional impairment outcomes. However, to our knowledge, no studies have examined how protective factors such as psychological grit mitigate the negative effects of lifetime and chronic stressor exposure on functional impairment, and how this association differs by HIV-status. To address this issue, we studied associations between lifetime and chronic stressor exposure, grit, and functional impairment in 176 African American and non-Hispanic White HIV-seropositive (n = 100) and HIV-seronegative (n = 76) adults, aged 24-85 (M = 57.28, SD = 9.02). As hypothesised, HIV-seropositive status and lower grit, but not lifetime stressor exposure, were independently associated with more functional impairment. Moreover, there was a significant three-way interaction between HIV-status, grit, and lifetime stressor exposure, b = 0.07, p = 0.025, 95% CI [0.009, 0.135]. Specifically, lifetime stressor exposure was related to more functional impairment for HIV-seronegative-but not HIV-seropositive-adults who reported low levels of grit. These findings suggest that the protective effects of grit may differ across populations at risk for functional impairment.

Loose bone and cement can promote polyethylene wear that may lead to failure in total knee arthroplasty. The authors propose a technique to enhance the debridement of loose bodies by distracting the cemented components with a lamina spreader following standard debridement with pulsatile lavage. Cement and bone/soft tissue debris was recovered from 51 consecutive primary total knee arthroplasty patients. This technique facilitated the removal of hidden debris in 80% of patients (41/51). On average, 2.6 fragments measuring 158 mm3 were removed per patient. The authors advocate that distraction with a lamina spreader be used to reduce potential sources of wear.

The E3 ligase RNF168 is essential for the signalling of DNA double strand break and its mutations are associated with the RIDDLE syndrome. Here the authors identify TOP2a as substrate for RNF168 and USP10; providing a link between the RNF168/USP10 axis, TOP2a and the response to anti-cancer drugs that target TOP2.

Osteomyelitis is an increasingly common pathology that often poses a diagnostic challenge to clinicians. Accurate and timely diagnosis is critical to preventing complications that can result in the loss of life or limb. In addition to history, physical exam, and laboratory studies, diagnostic imaging plays an essential role in the diagnostic process. This narrative review article discusses various imaging modalities employed to diagnose osteomyelitis: plain films, computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, bone scintigraphy, and positron emission tomography (PET). Articles were obtained from Pubmed and screened for relevance to the topic of diagnostic imaging for osteomyelitis. The authors conclude that plain films are an appropriate first step, as they may reveal osteolytic changes and can help rule out alternative pathology. MRI is often the most appropriate second study, as it is highly sensitive and can detect bone marrow changes within days of an infection. Other studies such as CT, ultrasound, and bone scintigraphy may be useful in patients who cannot undergo MRI. CT is useful for identifying necrotic bone in chronic infections. Ultrasound may be useful in children or those with sickle-cell disease. Bone scintigraphy is particularly useful for vertebral osteomyelitis. Finally, PET scan has demonstrated high sensitivity and specificity; however, its clinical application is limited by its high cost and poor availability. When used appropriately, diagnostic imaging can provide high sensitivity and specificity for detecting osteomyelitis, making radiographic evaluation a crucial step in the diagnostic process of this debilitating condition.

Vitamin K is known to play an essential role in the coagulation cascade; however, a growing body of research has found that a subtype of this vitamin, vitamin K2 (menaquinone) may have a beneficial effect in osteoporosis, cardiovascular disease, and cancer. This purpose of this article is to provide a comprehensive review of recent literature regarding menaquinone and its role in human health. This review discusses the physiology of menaquinone, its clinical benefits in cardiovascular disease, osteoporosis, and cancer, and how it may interact with certain medications. The authors conclude that menaquinone supplementation has been shown to improve carboxylation of osteocalcin and matrix-Gla protein to their active forms, two proteins that possess important roles in calcium distribution. In the setting of cardiovascular disease, menaquinone intake has been shown to lower the risk of coronary calcification and coronary heart disease, and a randomized controlled trial has demonstrated that it can reduce arterial stiffness. In osteoporosis, menaquinone has been shown by numerous randomized controlled trials to decrease the rate of bone loss at the lumbar spine and forearm and reduce the risk of fracture. In cancer, menaquinone intake has been shown to reduce overall incidence and mortality; clinical trials have suggested that it may have a role in reducing recurrence and death from hepatocellular carcinoma. However, in all clinical settings, more large randomized controlled trials are needed to definitively determine the clinical benefits of menaquinone supplementation, as many studies have failed to show any significant benefit. Lastly, more research is needed to determine how menaquinone supplementation interacts with medications such as warfarin, bile-acid sequestrants, orlistat, mineral oil and CYP3A4 substrates.

In the last decade, texting and driving has evolved into a serious problem among the adolescent population. The goal of this study was to determine if education can effectively raise awareness of the dangers of texting and driving and positively influence the behavior of rural West Virginia teens. A 25 question survey designed to asses teen driving behavior was administered to 143 rural West Virginia high school students before and after and educational session. The educational session was designed to explain how texting and driving impairs driving ability and show graphic images of accidents and injuries that resulted from this behavior. Pre and post-lecture survey responses were then analyzed. The survey results revealed that texting and driving is highly prevalent among rural West Virginia teens, with 57% of teens admitting to this behavior. Around 73% of teens agreed that texting and driving was very dangerous, but many continued to do so regardless. Additionally, 59% admitted to talking on the phone while driving, and 11% admitted to drinking and driving. A single lecture was not observed to reduce texting and driving behavior among the study population. More research is needed to establish an effective method to reduce this dangerous behavior.

Vitamin D is known to play an essential role in calcium homeostasis; however, excessive amounts can have harmful effects. Calcium and vitamin D levels are known to be influenced by drug interactions and pathology ranging from of cancer to cardiovascular disease. Vitamin D supplementation has become widespread, and it is important for clinicians to understand the way that certain conditions and medications interact with vitamin D and calcium homeostasis. The purpose of this review is to outline the benefits and adverse effects of vitamin D and how its levels are affected by certain pathologic and pharmacologic interactions.

Stereotypic cell migrations in the developing brain are fundamental for the proper patterning of brain regions and formation of neural networks. In this work, we uncovered in the developing rat, a population of neurons expressing tyrosine hydroxylase (TH) that migrates posteriorly from the alar plate of the midbrain, in neurophilic interaction with axons of the mesencephalic nucleus of the trigeminal nerve. A fraction of this population was also shown to traverse the mid-hindbrain boundary, reaching the vicinity of the locus coeruleus (LC) in rhombomere 1 (r1). This migratory population, however, does not have a noradrenergic (NA) phenotype and, in keeping with its midbrain origin, expresses Otx2 which is down regulated upon migration into the hindbrain. The interaction with the trigeminal mesencephalic axons is necessary for the arrangement and distribution of migratory cells as these aspects are dramatically altered in whole embryo cultures upon disruption of trigeminal axon projection by interfering with DCC function. Moreover, in mouse embryos in an equivalent developmental stage, we detected a cell population that also migrates caudally within the midbrain apposed to mesencephalic trigeminal axons but that does not express TH; a fraction of this population expresses calbindin instead. Overall, our work identified TH-expressing neurons from the rat midbrain alar plate that migrate tangentially over long distances within the midbrain and into the hindbrain by means of a close interaction with trigeminal mesencephalic axons. A different migratory population in this region and also in mouse embryos revealed diversity among the cells that follow this descending migratory pathway.

Objective: The heterogeneity of amyotrophic lateral sclerosis (ALS) survival duration, which varies from 10 years, challenges clinical decisions and trials. Utilizing data from 801 deceased ALS patients, we: (1) assess the underlying complex relationships among common clinical ALS metrics; (2) identify which clinical ALS metrics are the “best” survival predictors and how their predictive ability changes as a function of disease progression.Methods: Analyses included examination of relationships within the raw data as well as the construction of interactive survival regression and classification models (generalized linear model and random forests model). Dimensionality reduction and feature clustering enabled decomposition of clinical variable contributions. Thirty-eight metrics were utilized, including Medical Research Council (MRC) muscle scores; respiratory function, including forced vital capacity (FVC) and FVC % predicted, oxygen saturation, negative inspiratory force (NIF); the Revised ALS Functional Rating Scale (ALSFRS-R) and its activities of daily living (ADL) and respiratory sub-scores; body weight; onset type, onset age, gender, and height. Prognostic random forest models confirm the dominance of patient age-related parameters decline in classifying survival at thresholds of 30, 60, 90, and 180 days and 1, 2, 3, 4, and 5 years.Results: Collective prognostic insight derived from the overall investigation includes: multi-dimensionality of ALSFRS-R scores suggests cautious usage for survival forecasting; upper and lower extremities independently degenerate and are autonomous from respiratory decline, with the latter associating with nearer-to-death classifications; height and weight-based metrics are auxiliary predictors for farther-from-death classifications; sex and onset site (limb, bulbar) are not independent survival predictors due to age co-correlation.Conclusion: The dimensionality and fluctuating predictors of ALS survival must be considered when developing predictive models for clinical trial development or in-clinic usage. Additional independent metrics and possible revisions to current metrics, like the ALSFRS-R, are needed to capture the underlying complexity needed for population and personalized forecasting of survival.

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the causative agent of several human malignancies. Human tumour viruses such as KSHV are known to interact with the DNA damage response (DDR), the molecular pathways that recognise and repair lesions in cellular DNA. Here it is demonstrated that lytic reactivation of KSHV leads to activation of the ATM and DNA-PK DDR kinases resulting in phosphorylation of multiple downstream substrates. Inhibition of ATM results in the reduction of overall levels of viral replication while inhibition of DNA-PK increases activation of ATM and leads to earlier viral release. There is no activation of the ATR-CHK1 pathway following lytic replication and CHK1 phosphorylation is inhibited at later times during the lytic cycle. Despite evidence of double-strand breaks and phosphorylation of H2AX, 53BP1 foci are not consistently observed in cells containing lytic virus although RPA32 and MRE11 localise to sites of viral DNA synthesis. Activation of the DDR following KSHV lytic reactivation does not result in a G1 cell cycle block and cells are able to proceed to S-phase during the lytic cycle. KSHV appears then to selectively activate DDR pathways, modulate cell cycle progression and recruit DDR proteins to sites of viral replication during the lytic cycle.

The effects of acute stress on memory encoding are complex, and we do not yet know all of the conditions that can determine whether stress at encoding improves or impairs memory. Recent work has found that changing contexts between encoding and stress can abolish the effects of post-encoding stress on memory, suggesting that context may play an important role in the effects of stress on memory. However, the role of context in the effects of stress on memory encoding is not yet known. We addressed this gap by examining the effects of context on the influence of acute stress on memory encoding. In a 2 × 2 experimental design, participants (N = 103) completed either a stressor (i.e., Socially Evaluated Cold Presser Test) or control task (i.e., warm water control) before completing a memory encoding task, which occurred in either in the same room as or a different room from the stressor or control task. Memory retrieval was tested for each participant within the context that they completed the encoding task. We found that, relative to nonstressed (i.e., control) participants, stressed participants who switched contexts prior to encoding showed better memory for both negative and neutral images. In contrast, when the stressor or control task occurred in the same room as memory encoding, stress had no beneficial effect on memory. These results highlight the importance of the ongoing context as a determinant of the effects of stress on memory encoding and present a challenge to current theoretical accounts of stress and memory.

Norovirus is the leading cause of gastroenteritis worldwide. Despite recent developments in norovirus propagation in cell culture, these viruses are still challenging to grow routinely. Moreover, little is known on how norovirus infects the host cells, except that histo-blood group antigens (HBGAs) are important binding factors for infection and cell entry. Antibodies that bind at the HBGA pocket and block attachment to HBGAs are believed to neutralize the virus. However, additional neutralization epitopes elsewhere on the capsid likely exist and impeding the intrinsic structural dynamics of the capsid could be equally important. In the current study, we investigated a panel of Nanobodies in order to probe functional epitopes that could trigger capsid rearrangement and/ or interfere with HBGA binding interactions. The precise binding sites of six Nanobodies (Nano-4, Nano-14, Nano-26, Nano-27, Nano-32, and Nano-42) were identified using X-ray crystallography. We showed that these Nanobodies bound on the top, side, and bottom of the norovirus protruding domain. The impact of Nanobody binding on norovirus capsid morphology was analyzed using electron microscopy and dynamic light scattering. We discovered that distinct Nanobody epitopes were associated with varied changes in particle structural integrity and assembly. Interestingly, certain Nanobody-induced capsid morphological changes lead to the capsid protein degradation and viral RNA exposure. Moreover, Nanobodies employed multiple inhibition mechanisms to prevent norovirus attachment to HBGAs, which included steric obstruction (Nano-14), allosteric interference (Nano-32), and violation of normal capsid morphology (Nano-26 and Nano-85). Finally, we showed that two Nanobodies (Nano-26 and Nano-85) not only compromised capsid integrity and inhibited VLPs attachment to HBGAs, but also recognized a broad panel of norovirus genotypes with high affinities. Consequently, Nano-26 and Nano-85 have a great potential to function as novel therapeutic agents against human noroviruses.

Human noroviruses (huNoV) are the most frequent cause of non-bacterial acute gastroenteritis worldwide, particularly genogroup II genotype 4 (GII.4) variants. The viral nonstructural (NS) proteins encoded by the ORF1 polyprotein induce vesical clusters harboring the viral replication sites. Little is known so far about the ultrastructure of these replication organelles or the contribution of individual NS proteins to their biogenesis. We compared the ultrastructural changes induced by expression of norovirus ORF1 polyproteins with those induced upon infection with murine norovirus (MNV). Characteristic membrane alterations induced by ORF1 expression resembled those found in MNV infected cells, consisting of vesicle accumulations likely built from the endoplasmic reticulum (ER) which included single membrane vesicles (SMVs), double membrane vesicles (DMVs) and multi membrane vesicles (MMVs). In-depth analysis using electron tomography suggested that MMVs originate through the enwrapping of SMVs with tubular structures similar to mechanisms reported for picornaviruses. Expression of GII.4 NS1-2, NS3 and NS4 fused to GFP revealed distinct membrane alterations when analyzed by correlative light and electron microscopy. Expression of NS1-2 induced proliferation of smooth ER membranes forming long tubular structures that were affected by mutations in the active center of the putative NS1-2 hydrolase domain. NS3 was associated with ER membranes around lipid droplets (LDs) and induced the formation of convoluted membranes, which were even more pronounced in case of NS4. Interestingly, NS4 was the only GII.4 protein capable of inducing SMV and DMV formation when expressed individually. Our work provides the first ultrastructural analysis of norovirus GII.4 induced vesicle clusters and suggests that their morphology and biogenesis is most similar to picornaviruses. We further identified NS4 as a key factor in the formation of membrane alterations of huNoV and provide models of the putative membrane topologies of NS1-2, NS3 and NS4 to guide future studies.

ABSTRACT Typically, human noroviruses cause symptoms of acute gastroenteritis for 2 to 4 days. Often, the virions are shed in stool for several days after the symptoms recede, which in turn can lead to further contamination and transmission. Moreover, a number of reports have considered that chronic norovirus infections, i.e., lasting months and years, might even function as reservoirs for the generation of novel strains that can escape the herd immunity or have modified binding interactions with histo-blood group antigens (HBGAs). In this study, we analyzed noroviruses isolated from a patient who has presented a chronic infection for more than 6 years. We found that the isolated capsid sequences clustered into two main genetic types (termed A and B), despite a plethora of capsid quasi-sequences. Furthermore, the two genetic types corresponded well with distinct antigenicities. On the other hand, we showed that numerous amino acid substitutions on the capsid surface of genetic types A and B did not alter the HBGA binding profiles. However, divergent binding profiles for types A and B were observed with human milk oligosaccharides (HMOs), which structurally mimic HBGAs and may act as natural antivirals. Importantly, the isolated capsid sequences only had approximately 90% amino acid identity with other known sequences, which suggested that transmission of these chronic noroviruses could be limited. IMPORTANCE The norovirus genogroup II genotype 4 (GII.4) variants have approximately 5% divergence in capsid amino acid identity and have dominated over the past decade. The precise reason(s) for the GII.4 emergence and persistence in the human population is still unknown, but some studies have suggested that chronically infected patients might generate novel variants that can cause new epidemics. We examined GII.4 noroviruses isolated from an immunocompromised patient with a long-term infection. Numerous norovirus capsid quasi-species were isolated during the 13-month study. The capsid quasi-species clustered into two genetic and antigenic types. However, the HBGA binding profiles were similar between the two antigenic clusters, indicating that the amino acid substitutions did not alter the HBGA binding interactions. The isolated sequences represented two new GII.4 variants, but similar sequences were not found in the database. These results indicated that chronically infected patients might not generate novel noroviruses that cause outbreaks.

Roads now penetrate even the most remote parts of much of the world, but the majority of research on the effects of roads on biota has been in less remote temperate environments. The impacts of roads in semi-arid and arid areas may differ from these results in a number of ways. Here, we review the research on the impacts of roads on biodiversity patterns and ecological and evolutionary processes in semi-arid regions. The most obvious effect of roads is mortality or injury through collision. A diversity of scavengers are killed whilst feeding on roadkill, a source of easily accessed food. Noise pollution from roads and traffic interferes with vocal communication by animals, and birds and frogs living along noisy roads compensate for traffic noise by increasing the amplitude or pitch of their calls. Artificial light along roads impacts certain species’ ability to navigate, as well as attracting invertebrates. Animals are in turn attracted to invertebrates at streetlights, and vulnerable to becoming roadkill themselves. Genetics research across taxa confirms a loss of genetic diversity in small populations isolated by roads, but the long-term impact on the fitness of affected populations through a reduction in genetic diversity is not yet clear. Roads may rapidly cause genetic effects, raising conservation concerns about rare and threatened species. We assess mitigation measures and collate methods to identify the impact of roads on wildlife populations and their associated ecosystems, with a particular focus on recent advances.

A successful enone version of an intramolecular aza-[3 + 3] annulation reaction is described here. Use of piperidinium trifluoroacetate salt as the catalyst and toluene as the solvent appears to be critical for a successful annulation. We also demonstrated for the first time that microwave irradiation can accelerate aza-[3 + 3] annulation reactions. An attempt to expand the scope of the enone aza-[3 + 3] annulation was made in the form of propyleine synthesis as a proof of concept. While synthesis of the enone annulation precursor was successfully accomplished, the annulation proved to be challenging and was only modestly successful.

ABSTRACT Human noroviruses are the dominant cause of outbreaks of acute gastroenteritis. These viruses are usually detected by molecular methods, including reverse transcriptase PCR (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Human noroviruses are genetically and antigenically diverse, with two main genogroups that are further subdivided into over 40 different genotypes. During the past decade, genogroup 2 genotype 4 (GII.4) has dominated in most countries, but recently, viruses belonging to GII.17 have increased in prevalence in a number of countries. A number of commercially available ELISAs and lateral flow immunoassays were found to have lower sensitivities to the GII.17 viruses, indicating that the antibodies used in these methods may not have a high level of cross-reactivity. In this study, we developed a rapid Nanobody-based lateral flow immunoassay (Nano-immunochromatography [Nano-IC]) for the detection of human norovirus in clinical specimens. The Nano-IC assay detected virions from two GII.4 norovirus clusters, which included the current dominant strain and a novel variant strain. The Nano-IC method had a sensitivity of 80% and specificity of 86% for outbreak specimens. Norovirus virus-like particles (VLPs) representing four genotypes (GII.4, GII.10, GII.12, and GII.17) could be detected by this method, demonstrating the potential in clinical screening. However, further modifications to the Nano-IC method are needed in order to improve this sensitivity, which may be achieved by the addition of other broadly reactive Nanobodies to the system. IMPORTANCE We previously identified a Nanobody (termed Nano-85) that bound to a highly conserved region on the norovirus capsid. In this study, the Nanobody was biotinylated and gold conjugated for a lateral flow immunoassay (termed Nano-IC). We showed that the Nano-IC assay was capable of detecting at least four antigenically distinct GII genotypes, including the newly emerging GII.17. In the clinical setting, the Nano-IC assay had sensitivities equivalent to other commercially available lateral flow systems. The Nano-IC method was capable of producing results in ~5 min, which makes this method useful in settings that require rapid diagnosis, such as cruise ship outbreaks and elder care facilities. The Nano-IC assay has several advantages over antibody-based IC methods: for example, Nanobodies can be readily produced in large quantities, they are generally more stable than conventional antibodies, and the Nanobody binding sites can be easily obtained by X-ray crystallography.

ABSTRACT Human norovirus interacts with the polymorphic human histo-blood group antigens (HBGAs), and this interaction is thought to be important for infection. The genogroup II genotype 4 (GII.4) noroviruses are the dominant cluster, evolve every other year, and are thought to modify their binding interactions with different HBGA types. Most human noroviruses bind HBGAs, while some strains were found to have minimal or no HBGA interactions. Here, we explain some possible structural constraints for several noroviruses that were found to bind poorly to HBGAs by using X-ray crystallography. We showed that one aspartic acid was flexible or positioned away from the fucose moiety of the HBGAs and this likely hindered binding, although other fucose-interacting residues were perfectly oriented. Interestingly, a neighboring loop also appeared to influence the loop hosting the aspartic acid. These new findings might explain why some human noroviruses bound HBGAs poorly, although further studies are required.

Patients with biallelic truncating mutations in PALB2 have a severe form of Fanconi anaemia (FA-N), with a predisposition for developing embryonal-type tumours in infancy. Here we describe two unusual patients from a single family, carrying biallelic PALB2 mutations, one truncating, c.1676_1677delAAinsG;(p.Gln559ArgfsTer2), and the second, c.2586+1G>A; p.Thr839_Lys862del resulting in an in frame skip of exon 6 (24 amino acids). Strikingly, the affected individuals did not exhibit the severe developmental defects typical of FA-N patients and initially presented with B cell non-Hodgkin lymphoma. The expressed p.Thr839_Lys862del mutant PALB2 protein retained the ability to interact with BRCA2, previously unreported in FA-N patients. There was also a large increased chromosomal radiosensitivity following irradiation in G2 and increased sensitivity to mitomycin C. Although patient cells were unable to form Rad51 foci following exposure to either DNA damaging agent, U2OS cells, in which the mutant PALB2 with in frame skip of exon 6 was induced, did show recruitment of Rad51 to foci following damage. We conclude that a very mild form of FA-N exists arising from a hypomorphic PALB2 allele.

The adoption of Common Core State Standards in the USA by 46 states and the District of Columbia has provided several new foci for K-12 instruction, not the least of which is the reading and understanding of complex text, a higher order thinking process. Closely associated with this is the notion of rigor, the focus of the present study. As educators who work with administrators and teachers across the country, we have noticed that while there exists a general concern about rigor, there is not a coherent understanding of what it is. As such, there is a need to establish a common understanding of rigor that is useful for school-based personnel. Additionally, we propose that it’s important for educators to regularly measure and track rigor as one part of a larger dashboard of quality indicators which can inform school leaders on the educational health of their school.

Fetal parvovirus B19 infection causes anemia, hydrops, and pregnancy loss but is generally not considered teratogenic. Nevertheless, disturbances of neuronal migration have been described with congenital parvovirus infection. We evaluated a term infant with congenital parvovirus disease and polymicrogyria. We compared this case with four other reports of central nervous system disease after birth to parvovirus-infected mothers. After an extensive diagnostic evaluation, this infant was found to have congenital parvovirus disease with severe anemia and nonimmune hydrops as well as extensive polymicrogyria. Although rare, this report and literature review suggest that parvovirus B19 has the potential to disrupt normal neurodevelopment. We suggest that infants with severe congenital parvovirus infection have close developmental surveillance and if symptomatic undergo neuroimaging to assess for disorders of neuromigration.

Navigating growth cones are exposed to multiple signals simultaneously and have to integrate competing cues into a coherent navigational response. Integration of guidance cues is traditionally thought to occur at the level of cytoskeletal dynamics. Drosophila studies indicate that cells exhibit a low level of continuous caspase protease activation, and that axon guidance cues can activate or suppress caspase activity. We base a model for axon guidance on these observations. By analogy with other systems in which caspase signaling has non-apoptotic functions, we propose that caspase signaling can either reinforce repulsion or negate attraction in response to external guidance cues by cleaving cytoskeletal proteins. Over the course of an entire trajectory, incorrectly navigating axons may pass the threshold for apoptosis and be eliminated, whereas axons making correct decisions will survive. These observations would also explain why neurotrophic factors can act as axon guidance cues and why axon guidance systems such as Slit/Robo signaling may act as tumor suppressors in cancer.

Academic vocabulary is the specialized language used to communicate within academic settings. The Coxhead (2000) taxonomy is one such list that identifies 570 headwords representing academic vocabulary. Researchers have hypothesized that students possessing greater fluent reading skills are more likely to benefit from exposure to vocabulary due to greater amounts of time spent reading (Nagy and Stahl, 2007; Stanovich, 1986). In this study of 138 sixth- and seventh-grade students, we assess academic vocabulary, indicators of fluent reading, and silent reading comprehension to gain insight into relationships between the three. Our results found that reading rate mediates the relationship between academic vocabulary and reading comprehension, accounting for nearly one-third of the explained variance. Using simple slope analysis, we identified a threshold suggesting the point where reading rate exerts a neutral effect on reading comprehension beyond which vocabulary learning is no longer hindered.