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In pathology protocols, a tissue block, such as one containing a mouse brain or a biopsy sample from a patient, can produce several hundred thin sections. Substantial time may be required to analyse all sections. In cases of uncertainty regarding which sections to focus on, noninvasive scout imaging of intact blocks can help in guiding the pathology procedure. The scouting step is ideally done in a time window of minutes without special sample preparation that may interfere with the pathology procedures. The challenge is to obtain some visibility of unstained tissue structures at sub-10 µm resolution. We explored a novel x-ray tomosynthesis method as a way to maximise contrast-to-noise ratio, a determinant of tissue visibility. It provided a z-stack of thousands of images at 7.3 μm resolution (10% contrast, half-period of 68.5 line pairs/mm), in scans of 5-15 minutes. When compared with micro-CT scans, the straight-line tomosynthesis scan did not need to rotate the sample, which allowed flat samples, such as paraffin blocks, to be kept as close as possible to the x-ray source. Thus, given the same hardware, scan time and resolution, this mode maximised the photon flux density through the sample, which helped in maximising the contrast-to-noise ratio. The tradeoff of tomosynthesis is incomplete 3D information. The microtomosynthesis scanner has scanned 110 unstained human and animal tissue samples as part of their respective pathology protocols. In all cases, the z-stack of images showed tissue structures that guided sectioning or provided correlative structural information. We describe six examples that presented different levels of visibility of soft tissue structures. Additionally, in a set of coronary artery samples from an HIV patient donor, microtomosynthesis made a new discovery of isolated focal calcification in the internal elastic lamina of coronary wall, which was the onset of medial calcific sclerosis in the arteries.A microscopy version of the imaging method for 3D luggage screening has been adapted to image unstained pathology samples. Pathology tests of tissue samples are used for clinical diagnosis and for biomedical research. The tissue samples are often embedded in paraffin blocks and sectioned into many thin slices, which are then stained with the appropriate agents for light microscopy. Since each tissue block can produce several hundred thin sections, much time and labour is required to analyse all sections. Noninvasive scout imaging of intact blocks can help in guiding the pathology procedure. The scouting step is ideally done in a time window of minutes without special sample preparation that may interfere with the pathology procedures. The challenge is to obtain some visibility of unstained tissue structures at sufficient resolution. X-ray imaging is a promising tool to meet the challenge since x-rays can penetrate thick samples that are opaque to visible light. With x-ray imaging, a determinant of tissue visibility is the flux density of photons that illuminate the sample. We explored a novel x-ray tomosynthesis method as a way to maximise this factor. It provided a stack of thousands of cross-sectional images at 7.3 μm resolution (half-period of 68.5 line pairs/mm) in scans of 5-15 minutes. When compared with micro-CT scans (a widely used laboratory technology), this method did not need to rotate the sample, which allowed flat samples such as paraffin blocks to be kept as close as possible to the x-ray source. Thus, given the same hardware, scan time and resolution, this method maximised the photon flux density through the sample, which helped in improving the visibility of unstained tissue under x-ray. The tradeoff of the method is incomplete 3D information. Over 100 unstained human and animal tissue samples have been scanned with this method as part of their respective pathology protocols. In all cases, the stack of cross-sectional images showed tissue structures that guided pathology analysis or provided correlative structural information. We describe six examples that presented different levels of tissue visibility. Additionally, in a set of coronary artery samples from an HIV patient donor, microtomosynthesis made a new discovery of isolated focal calcification in the internal elastic lamina of coronary wall, which was the onset of medial calcific sclerosis in the arteries.

Biological rhythms mediate important within-host processes such as metabolism, immunity, and behavior which are often linked to combating disease exposure. For many hosts, exposure to pathogens occurs while feeding. However, the link between feeding rhythms and infection risk is unclear because feeding behavior is tightly coupled with immune and metabolic processes which may decrease susceptibility to infection. Here, we use the

A 54-year old female patient with the genetic disease of arterial calcification due to deficiency of CD73 was studied under the Undiagnosed Disease Program of the National Institutes of Health. She presented with symptoms of claudication in her 40s and later developed arthritic symptoms, ectopic calcification in her left hand and severe arterial calcifications of the lower extremities. Since little was known about the composition of the calcifications in arterial calcification due to deficiency of CD73, we investigated their chemical identity and microscopic morphology in this patient with imaging and x-ray diffraction analysis. We found that, microscopically, the bulk calcifications consisted of fragments of either solid or porous internal structure. Both periarticular and arterial calcifications were primarily hydroxyapatite crystals of the same crystalline anisotropy, but different crystalline grain sizes. This was consistent with the presence of hydroxyapatite crystals along with birefringent calcium pyrophosphate dihydrate crystals in the synovial fluid of the patients by polarized light microscopy. The result suggests that tissue calcification in both locations follow a similar biochemical mechanism caused by an increase in extracellular tissue-nonspecific alkaline phosphatase activity.

Precise genome editing is limited by the inefficiency of homology-directed repair (HDR) compared to the non-homologous end-joining (NHEJ) of double strand breaks (DSBs). The CRISPR (clustered regularly interspaced short palindromic repeat)/Cas9 system generates precise, locus-specific DSBs that can serve as substrates for HDR. We developed an in vivo visual reporter assay to quantify HDR-mediated events at single-cell resolution in zebrafish and used this system to identify small-molecule modulators that shift the DNA repair equilibrium in favor of HDR. By further optimizing the reaction environment and repair template, we achieved dramatic enhancement of HDR-mediated repair efficiency in zebrafish. Accordingly, under optimized conditions, inhibition of NHEJ with NU7441 enhanced HDR-mediated repair up to 13.4-fold. Importantly, we demonstrate that the increase in somatic HDR events correlates directly with germline transmission, permitting the efficient recovery of large seamlessly integrated DNA fragments in zebrafish., Aksoy et al. develop a reporter assay that allows them to quantify events mediated by homology-directed repair (HDR) in live zebrafish at single cell resolution. Using this assay, they systematically test and identify small molecule modulators that enhance the efficiency of HDR-mediated genome editing in zebrafish.

BACKGROUND:Adductor canal block (ACB) has emerged as an effective analgesic regional technique for major knee surgeries in the last decade. Its motor-sparing properties make it particularly attractive for ambulatory knee surgery, but evidence supporting its use in ambulatory arthroscopic knee surger

Wearable glasses are on the rising edge of development with great user popularity. However, user data stored on these devices bring privacy risks to the owner. To better protect the owner's privacy, a continuous authentication system is needed. In this paper, we propose a continuous and noninvasive authentication system for wearable glasses, named GlassGuard. GlassGuard discriminates the owner and an impostor with behavioral biometrics from six types of touch gestures (single-tap, swipe forward, swipe backward, swipe down, two-finger swipe forward, and two-finger swipe backward) and voice commands, which are all available during normal user interactions. With data collected from 32 users on Google Glass, we show that GlassGuard achieves 99% detection rate and 0.5% false alarm rate after 3.5 user events on average when all types of user events are available with equal probability. Under five typical usage scenarios, the system has a detection rate above 93% and a false alarm rate below 3% after less than five user events.

Regenerative capacity varies greatly between species. Mammals are limited in their ability to regenerate damaged cells, tissues and organs compared to organisms with robust regenerative responses, such as zebrafish. The regeneration of zebrafish tissues including the heart, spinal cord and retina requires foxp3a+ zebrafish regulatory T cells (zTregs). However, it remains unclear whether the muted regenerative responses in mammals are due to impaired recruitment and/or function of homologous mammalian regulatory T cell (Treg) populations. Here, we explore the possibility of enhancing zTreg recruitment with pharmacological interventions using the well-characterized zebrafish tail amputation model to establish a high-throughput screening platform. Injury-infiltrating zTregs were transgenically labelled to enable rapid quantification in live animals. We screened the NIH Clinical Collection (727 small molecules) for modulators of zTreg recruitment to the regenerating tissue at three days post-injury. We discovered that the dopamine agonist pramipexole, a drug currently approved for treating Parkinson&rsquo, s Disease, specifically enhanced zTreg recruitment after injury. The dopamine antagonist SCH-23390 blocked pramipexole activity, suggesting that peripheral dopaminergic signaling may regulate zTreg recruitment. Similar pharmacological approaches for enhancing mammalian Treg recruitment may be an important step in developing novel strategies for tissue regeneration in humans.

The box jellyfish Chironex fleckeri is extremely venomous, and envenoming causes tissue necrosis, extreme pain and death within minutes after severe exposure. Despite rapid and potent venom action, basic mechanistic insight is lacking. Here we perform molecular dissection of a jellyfish venom-induced cell death pathway by screening for host components required for venom exposure-induced cell death using genome-scale lenti-CRISPR mutagenesis. We identify the peripheral membrane protein ATP2B1, a calcium transporting ATPase, as one host factor required for venom cytotoxicity. Targeting ATP2B1 prevents venom action and confers long lasting protection. Informatics analysis of host genes required for venom cytotoxicity reveal pathways not previously implicated in cell death. We also discover a venom antidote that functions up to 15 minutes after exposure and suppresses tissue necrosis and pain in mice. These results highlight the power of whole genome CRISPR screening to investigate venom mechanisms of action and to rapidly identify new medicines., Box jellyfish venom causes tissue damage, pain, and death through unknown molecular mechanisms. Here, Lau et al. perform a CRISPR screen to identify genes required for venom action and use this information to develop an antidote that blocks venom-induced pain and tissue damage in vivo.

Chromium (Cr) is a vital environmental contaminant. In environmental matrixes, Cr presents dominantly in hexavalent chromium [Cr(VI)] and trivalent chromium [Cr(III)], which are two different inorganic states. Cr(VI) is a well-known human carcinogen, while Cr(III) is a naturally occurring micronutrient for the human body. Hence, speciation of Cr is crucial for ensuring environmental water and food safety. The distinction between each chromium species is almost impossible with commonly used methods like atomic spectrometric techniques, due to the low level of Cr and the high complexity of the matrix. Typically, a preconcentration step is required prior to determining and improving the selectivity and detection limit of the inspection instrument. For this process, nanocomposites, which are emerging high-quality adsorbents are used. However, preparation of previous nanocomposites suffered from a trivial synthesis process, had high reagent consumption, and was time-consuming. Therefore, we succinctly designed and fabricated the novel triadic silica gel-supported copper sulfide (CuS) nanocomposites for ultrasensitive detection of Cr(VI). CuS nanocomposites in a solid phase system were successfully applied to extract Cr(VI) in reference materials, such as food and water samples. Cr(VI) were detected by use of flame atomic absorption spectrometry (FAAS). By loading 30 mL of sample solution, a linear range of 0.5-300 μg L-1 with R = 0.998, a detection limit of 0.15 μg L-1, and an accuracy of 1.7% (20 μg L-1, n = 11) were obtained by this method. The detection limit and the precision of this procedure are superior to those reported in the literature with the same detection technique, indicating that CuS nanocomposites have a good potential for Cr(VI) detection which is essential for food safety and human health.

Existing research has demonstrated that inter-body sensor network (inter-BSN) information sharing among coexisting BSNs can enhance applications’ performance and save energy. However, how to achieve effective inter-BSN information sharing through wireless communication is a challenging task. On one hand, a BSN should be able to discover neighboring BSNs and establish inter-BSN links with quality of service (QoS) assurances. On the other hand, a BSN should be able to prevent the QoS of intra- and inter-BSN links from being degraded by multiple BSNs’ mutual interference. In this paper, we propose BuddyQoS, a framework that provides network throughput assurances for coexisting and shared buddy BSNs. In particular, BuddyQoS accurately estimates and adaptively schedules wireless resources to meet the throughput requirements of all inter- and intra-BSN links. Our trace-driven experiment results demonstrate that BuddyQoS outperforms the default CSMA solution in the standard TinyOS-2.x releases in terms of providing throughput assurances.

Background During treatment of Clostridium difficile infection (CDI), patterns of pathogen reduction in relationship to changes in components of the normal microbiota are hypothesized to be predictive of response to treatment and subsequent sustained cure. Methods At a single center, subjects enrolled into phase 2 and 3 C. difficile treatment clinical trials (2003-2008) provided fecal samples to assess killing of C. difficile and changes to components of the microbiome. Quantitative bacterial cultures, measurement of C. difficile toxin titers, quantitative polymerase chain reaction of fecal samples for Bacteroidetes, Clostridium clusters XIVa and IV, and C. difficile were performed. Results Quantitative bacterial cultures showed a mean log10 C. difficile count (colony-forming units [CFU]) of 6.7 ± 2.0 at study entry; vancomycin treatment consistently reduced C. difficile counts to the limit of detection (2.0 log10 CFU/g), whereas metronidazole was associated with mean C. difficile counts 1.5-2 log10 higher at 10 days of treatment. In patients receiving tolevamer, C. difficile persisted in high counts during treatment; response to treatment was correlated with neutralization of toxin along with persistence of normal microbiota components. However, this was achieved in approximately half of subjects. Both vancomycin and metronidazole further suppressed microbiome components during treatment of CDI. Lactobacilli were observed to be a microbiome component that persisted during treatment of CDI. Conclusions Differences of pathogen clearance and microbiome perturbation during treatment of CDI appear to explain treatment outcomes. The hypothesis that probiotic microbes could help prevent onset of CDI is supported by the observation of persistence of lactobacilli during and after treatment of CDI.

Wireless sensor network applications, such as those for natural disaster warning, vehicular traffic monitoring, and surveillance, have stringent accuracy requirements for detecting or classifying events and demand long system lifetimes. Through quantitative study, we show that existing event detection approaches are challenged to explore the sensing capability of a deployed system and choose the right sensors to meet user-specified accuracy. Event detection systems are also challenged to provide a generic system that efficiently adapts to environmental dynamics and works easily with a range of applications, machine learning approaches, and sensor modalities. Consequently, we propose Watchdog, a modality-agnostic event detection framework that clusters the right sensors to meet user-specified detection accuracy during runtime while significantly reducing energy consumption. Watchdog can use different machine learning techniques to learn the sensing capability of a heterogeneous sensor deployment and meet accuracy requirements. To address environmental dynamics and ensure energy savings, Watchdog wakes up and puts to sleep sensors as needed to meet user-specified accuracy. Through evaluation with real vehicle detection trace data and a building traffic monitoring testbed of IRIS motes, we demonstrate the superior performance of Watchdog over existing solutions in terms of meeting user-specified detection accuracy, energy savings, and environmental adaptability.

Background Identification of large vessel occlusions (LVO) is important with recent guidelines supporting endovascular therapy in selected acute ischemic stroke patients. Many stroke centers perform CT angiography (CTA) in patients with suspected LVO, however this requires additional time and contrast administration. Non-enhanced CT maximum intensity projection (NECT-MIPs) may offer a rapid alternative to CTA. Methods We retrospectively reviewed acute stroke patients with LVO in the UCSD Stroke Registry, presenting between 6/2014-7/2016. NECT-MIPs were evaluated for presence of LVO. Gold standard comparison was to CTA. Results were stratified by level of training (Faculty, Fellow and Acute Care Practitioners [ACPs]). Inter-rater agreement was assessed using Fleiss' Kappa Coefficient. Results We reviewed 24 patients using NECT-MIPs for the detection of LVO. Faculty had a sensitivity and specificity of 95% & 92% for ICA/M1, 42% & 100% for M2, and 67% & 96% for basilar occlusions. Fellows and ACPs had a sensitivity and specificity of 61% & 94% for ICA/M1, 19% & 83% for M2, and 75% & 95% for basilar occlusions. Inter-rater agreement among Faculty readers was k=0.75 for ICA/M1, k=0.79 for M2 and k=0.14 for basilar occlusions. Among Fellows and ACPs, k=0.57 for ICA/M1, k=0.40 for M2, and k=0.27 for basilar occlusions. Conclusions NECT-MIPs have high sensitivity and specificity for the detection of LVO when compared to CTA. Inter-rater agreement is fair and higher amongst more experienced reviewers. These results suggest that NECT-MIPs may be helpful to streamline the identification of LVO and reduce door to needle and door to intervention times.

Background: Since the introduction of recombinant tissue plasminogen activator (rt-PA) for acute ischemic stroke, rt-PA rate and number of stroke centers have increased. Despite this, studies have shown racial and ethnic disparities in stroke care especially in Black and Hispanic populations. How Hispanic ethnicity affects rt-PA evaluations has to date been unclear. In our patient population, we investigated whether ethnicity is associated with rt-PA use for acute ischemic strokes in the Hispanic population. Methods: We performed a retrospective review of IRB approved, prospectively collected data from the UC San Diego Stroke Registry. Patients were selected based on the presentation and primary diagnosis of Transient Ischemic Attack or Ischemic Stroke. Characteristics including risk factors were compared in Hispanic vs non-Hispanic samples to assess rt-PA treatment rates, process of care intervals for Hispanics vs non-Hispanics and rt-PA vs non-rt-PA patients. Results: We assessed 1489 patients (300 Hispanic vs. 1189 non-Hispanic whites) from July 2004 to July 2016. Comparing Hispanics to non-Hispanics, there was no difference in rt-PA rate (35.3% vs. 33.1%; p=0.49). In a subset evaluation of Hispanics only, comparing rt-PA(-) to rt-PA(+), there was no difference for male sex (56%), Hypertension (71%), Hyperlipidemia (29%), Diabetes (43%), Atrial Fibrillation (23%), and Smoking (20%). There was a noted difference in the Hispanic-only untreated vs treated subset for initial NIHSS (7.24 vs. 13.27; p Conclusions: This study shows the rate of rt-PA treatment and “door to treatment” intervals were not significantly different in Hispanic vs non-Hispanic patients. This data is supportive of current overall treatment decision models. However, the “onset to treatment” interval was significantly longer for Hispanic patients showing that it may take longer for this population to reach the treating hospital. This supports the need to develop culturally relevant education programs to address barriers in this population.

Our study reveals that facilitating warm launch of just five smartphone applications is extremely expensive, using up to 36 percent of memory. Further investigation of 20 popular applications indicates that rich multimedia applications have high heap usage and go above allowed boundaries, up to 5.63 times more heap than guaranteed by the system, and may cause crashes and erroneous behaviors. Therefore, we present iRAM, a personalized system that maintains optimal heap size limits to avoid crashes, efficiently maximizes free memory levels, and cleans low-priority processes to reduce application delays. The evaluation on memory hungry applications indicates that iRAM reduces application crashes by up to 14 percent, and reduces launch delays by up to 78.2 percent. In addition, the results confirm that iRAM increases free memory levels by up to 4.8 times. This performance gain comes with 3.5 percent of CPU overhead and 0.9 percent of power overhead.

The Burkholderia cepacia complex (Bcc) consists of 17 closely related species of opportunistic bacterial pathogens, which are particularly problematic for cystic fibrosis patients and immunocompromised individuals. Bcc genomes consist of multiple replicons, and each strain sequenced to date has three chromosomes. In addition to genes thought to be essential for survival, each chromosome carries at least one rRNA operon. We isolated three mutants during a transposon mutagenesis screen that were non-pathogenic in a Caenorhabditis elegans infection model. It was demonstrated that these mutants had lost chromosome 3 (c3), and that the observed attenuation of virulence was a consequence of this. We constructed a c3 mini-replicon and used it to cure c3 from strains of several Bcc species by plasmid incompatibility, resulting in nine c3-null strains covering seven Bcc species. Phenotypic characterization of c3-null mutants revealed that they were attenuated in virulence in multiple infection hosts (rat, zebrafish, C. elegans, Galleria mellonella and Drosophila melanogaster), that they exhibited greatly diminished antifungal activity, and that c3 was required for d-xylose, fatty acid and pyrimidine utilization, as well as for exopolysaccharide production and proteolytic activity in some strains. In conclusion, we show that c3 is not an essential chromosomal element, rather a large plasmid that encodes virulence, secondary metabolism and other accessory functions in Bcc bacteria.

Burkholderia cenocepacia is a significant opportunistic pathogen in individuals with cystic fibrosis. ShvR, a LysR-type transcriptional regulator, has previously been shown to influence colony morphology, biofilm formation, virulence in plant and animal infection models, and some quorum-sensing-dependent phenotypes. In the present study, it was shown that ShvR negatively regulates its own expression, as is typical for LysR-type regulators. The production of quorum-sensing signal molecules was detected earlier in growth in the shvR mutant than in the wild type, and ShvR repressed expression of the quorum-sensing regulatory genes cepIR and cciIR . Microarray analysis and transcriptional fusions revealed that ShvR regulated over 1,000 genes, including the zinc metalloproteases zmpA and zmpB . The shvR mutant displayed increased gene expression of the type II secretion system and significantly increased protease and lipase activities. Both ShvR and CepR influence expression of a 24-kb genomic region adjacent to shvR that includes the afcA and afcC operons, required for the production of an antifungal agent; however, the reduction in expression was substantially greater in the shvR mutant than in the cepR mutant. Only the shvR mutation resulted in reduced antifungal activity against Rhizoctonia solani. ShvR, but not CepR, was shown to directly regulate expression of the afcA and afcC promoters. In summary, ShvR was determined to have a significant influence on the expression of quorum-sensing, protease, lipase, type II secretion, and afc genes.

Over the past few decades, strains of the Burkholderia cepacia complex have emerged as important pathogens for patients suffering from cystic fibrosis. Identification of virulence factors and assessment of the pathogenic potential of Burkholderia strains have increased the need for appropriate infection models. In previous studies, different infection hosts, including mammals, nematodes, insects, and plants, have been used. At present, however, the extent to which the virulence factors required to infect different hosts overlap is not known. The aim of this study was to analyze the roles of various virulence factors of two closely related Burkholderia cenocepacia strains, H111 and the epidemic strain K56-2, in a multihost pathogenesis system using four different model organisms, namely, Caenorhabditis elegans , Galleria mellonella , the alfalfa plant, and mice or rats. We demonstrate that most of the identified virulence factors are specific for one of the infection models, and only three factors were found to be essential for full pathogenicity in several hosts: mutants defective in (i) quorum sensing, (ii) siderophore production, and (iii) lipopolysaccharide biosynthesis were attenuated in at least three of the infection models and thus may represent promising targets for the development of novel anti-infectives.