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Covering 55% of Canada’s total surface area and stretching from coast to coast to coast, the Canadian boreal zone is crucial to the nation’s economic and ecological integrity. Although often viewed as relatively underdeveloped, it is vulnerable to numerous stressors such as mining, forestry, and anthropogenic climate change. Natural archives preserved in lake sediments can provide key insights by quantifying pre-disturbance conditions (pre-1850 CE) and the nature, magnitude, direction, and speed of environmental change induced by anthropogenic stressors over the past ~150 years. Here, we paired a review of paleolimnological literature of the Canadian boreal zone with analyses of published sediment core data to highlight the effects of climate change, catchment disturbances, and atmospheric deposition on boreal lakes. Specifically, we conducted quantitative syntheses of two lake health indicators: elemental lead (Pb) and chlorophyll a. Segmented regressions and Mann-Kendall trend analysis revealed a generally increasing trend in elemental Pb across the boreal zone until ~1970 CE, followed by a generally decreasing trend to the present. Snapshot comparisons of sedimentary chlorophyll a from recent and pre-industrial sediments (i.e., top-bottom sediment core design) revealed that a majority of sites have increased over time, suggesting a general enhancement in lake primary production across the boreal zone. Collectively, this body of work demonstrates that long-term sediment records offer a critical perspective on ecosystem change not accessible through routine monitoring programs. We advocate using modern datasets in tandem with paleolimnology to establish baseline conditions, measure ecosystem changes, and set meaningful management targets.

Exposing macrophages to IFN-g or IL-4 polarizes them toward M1-like inflammatory or M2-like tissue repair phenotypes, respectively. It is uncertain whether the macrophage phenotypes are equally effective at phagocytosing melanoma and non-melanoma bait cells. We hypothesize that phenotypic polarization of macrophages will improve their phagocytic ability and that phagocytic vulnerability will depend on bait cell type. This study compares phenotypic polarization of macrophages on phagocytosis of LM-Mel-45 (LM45) melanoma cells and non-melanoma (Jurkat) cells at 2 h or 16 h. Macrophage differentiation to an M0 phenotype was induced by exposing THP-1 monocytes to 50 ng/ml PMA for two days, followed by 4 days rest in RPMI 1640, 10% FBS. M1-like and M2-like phenotypes were induced by 24 h exposure to 20 ng/ml IFN-γ and 20 ng/mL IL-4, respectively. Phenotypic state was measured by surface expression of CCR7, CD209, and CD172. Bait cells (LM45 or Jurkat) were treated with 0.5 mM staurosporine for 24 h to induce apoptosis and stained with CellTrace® Violet. Macrophages were stained with CellTracker® Orange CMRA. Bait cells were added to adherent macrophages to measure phagocytosis (2 or 16 h). To qualitatively monitor the phagocytic process, time-lapse imaging every 15 min for 16 h was done on a Zeiss Axiovert 200M microscope with a 10x objective. To quantify phagocytosis, adhered and loose cells were harvested and prepared for flow cytometry. Cells were analyzed for violet, orange, or both orange and violet staining. Positive phagocytosis was expressed as the percentage of orange macrophages with violet staining above the violet cutoff. M0 macrophages are positive for CD172. Exposure to IFN-γ increases levels of CD209 and CCR7, and CD172 remains present. Exposure to IL-4 increases levels of CD209 with little change in CCR7 and CD172 remains present. Time-lapse imaging shows phagocytosis of LM45 cells via a “nipping” behavior rather than engulfment. When Jurkat cells serve as bait, multiple bait cells will attach to a single macrophage. Blebbing in bait cells is seen by 8 h. Phagocytic rate toward LM45 cells over 2 h averaged 6.7 ± 1.8% for M0 macrophages and 5.6 ± 2.3% for IFN-γ treated macrophages. Phagocytic rate toward LM45 cells over 16 h averaged 13.9 ± 1.3% for M0 macrophages and 14.9 ± 1.8% for IFN-γ treated macrophages. The differences were not significant. Phagocytic rate toward Jurkat cells averaged 22.4 ± 3.5% for M0 macrophages and 26.9 ± 4.0% for IFN-γ treated macrophages. This difference was not significant. Phagocytosis was significantly greater for Jurkat cells than LM45 cells (P KCOM Graduate Program Grant #851-068 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Cancer is a significant healthcare issue, and early screening methods based on biomarker analysis in liquid biopsies are promising avenues to reduce mortality rates. Electrical detection of nucleic acids at the single molecule level could enable these applications. We examine the electrical detection of RNA cancer biomarkers (KRAS mutants G12C and G12V) as a single-molecule proof-of-concept electrical biosensor for cancer screening applications. We show that the electrical conductance is highly sensitive to the sequence, allowing discrimination of the mutants from a wild-type KRAS sequence differing in just one base. In addition to this high specificity, our results also show that these biosensors are sensitive down to an individual molecule with a high signal-to-noise ratio. These results pave the way for future miniaturized single-molecule electrical biosensors that could be groundbreaking for cancer screening and other applications.

Young patients with ectodermal dysplasia and Ehlers-Danlos Syndrome present with unique characteristics and corresponding treatment challenges. Congenitally missing teeth or conditions leading to premature tooth loss may be exhibited. Underdeveloped or easily traumatized oral structures are commonly seen and must be rehabilitated with care. These oral features can have a negative impact on the patients' quality of life and may implicate special considerations during dental treatment. This report follows the initial treatments of a 6-year-old patient with ectodermal dysplasia and a 20-year-old patient with Ehlers-Danlos Syndrome, with the incorporation of digital technologies in their subsequent oral rehabilitation. This article is protected by copyright. All rights reserved.

Plasmodiumsporozoites inoculated byAnophelesmosquitoes into the skin of the mammalian host migrate to the liver before infecting hepatocytes. Previous work demonstrated that early production of IL-6 in the liver is detrimental for the parasite growth, contributing to the acquisition of a long-lasting immune protection after immunization with live attenuated parasites. Considering that IL-6 ais a critical pro-inflammatory signal, we explored a novel approach whereby the parasite itself encodes for the murine IL-6 gene. We generated transgenicP. bergheiparasites that express murine IL-6 during liver stage development. Though IL-6 transgenic sporozoites develop into exo-erythrocytic forms in cultured hepatocytesin vitroandin vivo, these parasites were not capable of inducing a blood stage infection in mice. Furthermore, immunization of mice with transgenic IL-6-expressingP. bergheisporozoites elicited a long-lasting CD8+T cell-mediated protective immunity against a subsequent infectious sporozoite challenge. Collectively, this study demonstrates that parasite-encoded IL-6 attenuates parasite virulence with abortive liver stage ofPlasmodiuminfection, forming the basis of a novel suicide vaccine strategy to elicit protective antimalarial immunity.SummaryIL-6 was shown to controlPlasmodiumparasite development in the liver. Here, Belhimeur et al. generated a murine IL-6 transgenicPlasmodium berghei. These parasites show an arrest in hepatocyte development and protect mice against homologous and heterologous parasite challenge in a CD8-dependent manner.

The increasing connectivity of devices in our daily lives has driven the need for higher bandwidth in network and data centers. Recently, we have seen the development of 112Gb/s SerDes, particularly for long-reach interfaces [1– 3]. In high-density switch ASICs, we see an increasing demand to improve both area efficiency (mm2/lane) and signaling efficiencies (pJ/b) [1– 6]. In a switch ASIC, keeping the SerDes power low translates into broader system power savings since additional power and cost for cooling can be limited or even avoided entirely. One path forward to achieve these important system gains is co-packaged optics (CPO) with an extra-short-reach (XSR) interface. In these applications the switch ASIC and optical engine are no more than 50mm apart which represents a total loss of approximately 10dB at 106.25Gb/s.

G protein-coupled receptors (GPCRs) signal through activation of G proteins and subsequent modulation of downstream effectors. More recently, signaling mediated by β-arrestin has also been implicated in important physiological functions. This has led to great interest in the identification of biased ligands that favor either G protein or β-arrestinsignaling pathways. However, nearly all screening techniques for measuring β-arrestin recruitment have required C-terminal receptor modifications that can in principle alter protein interactions and thus signaling. Here, we have developed a novel luminescence-based assay to measure β-arrestin recruitment to the membrane or early endosomes by unmodified receptors. Our strategy uses NanoLuc, an engineered luciferase from Oplophorus gracilirostris (deep-sea shrimp) that is smaller and brighter than other well-established luciferases. Recently, several publications have explored functional NanoLuc split sites for use in complementation assays. We have identified a unique split site within NanoLuc and fused the corresponding N-terminal fragment to either a plasma membrane or early endosome tether and the C-terminal fragment to β-arrestins, which form the basis for the MeNArC and EeNArC assays, respectively. Upon receptor activation, β-arrestin is recruited to the membrane and subsequently internalized in an agonist concentration-dependent manner. This recruitment promotes complementation of the two NanoLuc fragments, thereby reconstituting functional NanoLuc, allowing for quantification of β-arrestin recruitment with a single luminescence signal. Our assay avoids potential artifacts related to C-terminal receptor modification and has promise as a new generic assay for measuring β-arrestin recruitment to diverse GPCR types in heterologous or native cells.

Resistance to multimodal chemotherapy continues to limit the prognosis of acute lymphoblastic leukemia (ALL). This occurs in part through a process called adhesion-mediated drug resistance, which depends on ALL cell adhesion to the stroma through adhesion molecules, including integrins. Integrin α6 has been implicated in minimal residual disease in ALL and in the migration of ALL cells to the central nervous system. However, it has not been evaluated in the context of chemotherapeutic resistance. Here, we show that the anti-human α6-blocking Ab P5G10 induces apoptosis in primary ALL cells in vitro and sensitizes primary ALL cells to chemotherapy or tyrosine kinase inhibition in vitro and in vivo. We further analyzed the underlying mechanism of α6-associated apoptosis using a conditional knockout model of α6 in murine BCR-ABL1+ B-cell ALL cells and showed that α6-deficient ALL cells underwent apoptosis. In vivo deletion of α6 in combination with tyrosine kinase inhibitor (TKI) treatment was more effective in eradicating ALL than treatment with a TKI (nilotinib) alone. Proteomic analysis revealed that α6 deletion in murine ALL was associated with changes in Src signaling, including the upregulation of phosphorylated Lyn (pTyr507) and Fyn (pTyr530). Thus, our data support α6 as a novel therapeutic target for ALL.

Tumour fitness landscapes underpin selection in cancer, impacting etiology, evolution and response to treatment. Progress in defining fitness landscapes has been impeded by a lack of timeseries perturbation experiments over realistic intervals at single cell resolution. We studied the nature of clonal dynamics induced by genetic and pharmacologic perturbation with a quantitative fitness model developed to ascribe quantitative selective coefficients to individual cancer clones, enable prediction of clone-specific growth potential, and forecast competitive clonal dynamics over time. We applied the model to serial single cell genome (>60,000 cells) and transcriptome (>58,000 cells) experiments ranging from 10 months to 2.5 years in duration. We found that genetic perturbation ofTP53in epithelial cell lines induces multiple forms of copy number alteration that confer increased fitness to clonal populations with measurable consequences on gene expression. In patient derived xenografts, predicted selective coefficients accurately forecasted clonal competition dynamics, that were validated with timeseries sampling of experimentally engineered mixtures of low and high fitness clones. In cisplatin-treated patient derived xenografts, the fitness landscape was inverted in a time-dependent manner, whereby a drug resistant clone emerged from a phylogenetic lineage of low fitness clones, and high fitness clones were eradicated. Moreover, clonal selection mediated reversible drug response early in the selection process, whereas late dynamics in genomically fixed clones were associated with transcriptional plasticity on a fixed clonal genotype. Together, our findings outline causal mechanisms with implication for interpreting how mutations and multi-faceted drug resistance mechanisms shape the etiology and cellular fitness of human cancers.

Purpose To determine the therapeutic window for gene augmentation for Leber congenital amaurosis (LCA) associated with mutations in LCA5. Methods Five patients (ages 6-31) with LCA and biallelic LCA5 mutations underwent an ophthalmic examination including optical coherence tomography (SD-OCT), full-field stimulus testing (FST), and pupillometry. The time course of photoreceptor degeneration in the Lca5gt/gt mouse model and the efficacy of subretinal gene augmentation therapy with AAV8-hLCA5 delivered at postnatal day 5 (P5) (early, n = 11 eyes), P15 (mid, n = 14), and P30 (late, n = 13) were assessed using SD-OCT, histologic study, electroretinography (ERG), and pupillometry. Comparisons were made with the human disease. Results Patients with LCA5-LCA showed a maculopathy with detectable outer nuclear layer (ONL) in the pericentral retina and at least 4 log units of dark-adapted sensitivity loss. The Lca5gt/gt mouse has a similarly severe and rapid photoreceptor degeneration. The ONL became progressively thinner and was undetectable by P60. Rod- and cone-mediated ERGs were severely reduced in amplitudes at P30 and became nondetectable by P60. Subretinal AAV8-hLCA5 administered to Lca5gt/gt mice at P5 and P15, but not at P30, resulted in structural and functional rescue. Conclusions LCA5-LCA is a particularly severe form of LCA that was recapitulated in the Lca5gt/gt mouse. Gene augmentation resulted in structural and functional rescue in the Lca5gt/gt mouse if delivered before P30. Retained photoreceptors were visible within the central retina in all patients with LCA5-LCA, at a level equivalent to that observed in rescued Lca5gt/gt mice, suggesting a window of opportunity for the treatment of patients with LCA5-LCA.

G protein-coupled receptors (GPCRs) signal through activation of G proteins and subsequent modulation of downstream effectors. More recently, G protein-independent signaling via the arrestin pathway has also been implicated in important physiological functions. This has led to great interest in the identification of biased ligands that favor either the G protein or arrestin-signaling pathways. Currently available screening techniques that measure arrestin recruitment have required C-terminal receptor modifications that can in principle alter protein interactions and thus signaling. Here, we have developed a novel luminescence-based assay to measure arrestin recruitment to any unmodified receptor.NanoLuc, an engineered luciferase from ophlorus gracilirostris (deep sea shrimp), is smaller and brighter than other well-established luciferases. Recently, several publications have explored functional NanoLuc split sites for use in complementation assays. Here, we have identified a novel split site and have fused the N-terminal fragment to a membrane tether and the C-terminal fragment to the N-terminus of either β-arrestin 1 or 2. Upon receptor activation, arrestin is recruited to the plasma membrane in an agonist concentration-dependent manner and the two NanoLuc fragments complement to reconstitute functional luciferase, which allows quantification of recruitment with a single luminescence signal. Our assay avoids potential artifacts related to C-terminal receptor modification. The split NanoLuc arrestin recruitment assay has promise as a new generic assay for measuring arrestin recruitment to diverse GPCR types in heterologous or native cells.

Item does not contain fulltext Most genetically distinct inherited retinal degenerations are primary photoreceptor degenerations. We selected a severe early onset form of Leber congenital amaurosis (LCA), caused by mutations in the gene LCA5, in order to test the efficacy of gene augmentation therapy for a ciliopathy. The LCA5-encoded protein, Lebercilin, is essential for the trafficking of proteins and vesicles to the photoreceptor outer segment. Using the AAV serotype AAV7m8 to deliver a human LCA5 cDNA into an Lca5 null mouse model of LCA5, we show partial rescue of retinal structure and visual function. Specifically, we observed restoration of rod-and-cone-driven electroretinograms in about 25% of injected eyes, restoration of pupillary light responses in the majority of treated eyes, an approximately 20-fold decrease in target luminance necessary for visually guided behavior, and improved retinal architecture following gene transfer. Using LCA5 patient-derived iPSC-RPEs, we show that delivery of the LCA5 cDNA restores lebercilin protein and rescues cilia quantity. The results presented in this study support a path forward aiming to develop safety and efficacy trials for gene augmentation therapy in human subjects with LCA5 mutations. They also provide the framework for measuring the effects of intervention in ciliopathies and other severe, early-onset blinding conditions.

Author(s): Barton, Elisabeth R; Pham, Jennifer; Brisson, Becky K; Park, SooHyun; Smith, Lucas R; Liu, Min; Tian, Zuozhen; Hammers, David W; Vassilakos, Georgios; Sweeney, H Lee | Abstract: IntroductionDysferlin loss-of-function mutations cause muscular dystrophy, accompanied by impaired membrane repair and muscle weakness. Growth promoting strategies including insulin-like growth factor 1 (IGF-1) could provide benefit but may cause strength loss or be ineffective. The objective of this study was to determine whether locally increased IGF-1 promotes functional muscle hypertrophy in dysferlin-null (Dysf-/- ) mice.MethodsMuscle-specific transgenic expression and postnatal viral delivery of Igf1 were used in Dysf-/- and control mice. Increased IGF-1 levels were confirmed by enzyme-linked immunosorbent assay. Testing for skeletal muscle mass and function was performed in male and female mice.ResultsMuscle hypertrophy occurred in response to increased IGF-1 in mice with and without dysferlin. Male mice showed a more robust response compared with females. Increased IGF-1 did not cause loss of force per cross-sectional area in Dysf-/- muscles.DiscussionWe conclude that increased local IGF-1 promotes functional hypertrophy when dysferlin is absent and reestablishes IGF-1 as a potential therapeutic for dysferlinopathies.

The scaling of CMOS technology together with continued innovations in circuit and system design techniques is fueling a rising demand for increasingly high throughput serial data interfaces. However, advances in CMOS technology have little impact on channel performance, making channel impairments a bottleneck in wireline links. Furthermore, links are typically designed to cover multiple standards and are expected to operate over a wide range of data rates, making their design challenging [1-5]. This work presents a 4-lane 1.25–28.05Gb/s transceiver in 14nm FinFet technology. We measure a bit error rate (BER) lower than 1e-15 with a channel loss of 40dB at 28.05Gb/s.

In the first phase of this research, we conducted, audio-recorded, and transcribed seven focus groups with more than 50 English- or Spanish-speaking women of childbearing age. Qualitative analysis revealed the following themes: (1) expectation that participation would involve relationships based on trust that is built over time and impacted by cultural factors; (2) perceived characteristics of research staff that would help facilitate the development of trusting relationships; (3) perceptions about the location of the visits that may affect trust; (4) perceptions of a research study and trust for the institution conducting the study may affect trust; (5) connecting the study to larger communities, including faith communities, could affect trust and willingness to participate. In the second phase of this research, we conducted, recorded, transcribed, and analyzed interviews with leaders from diverse faith communities to explore the potential for research partnerships between researchers and faith communities. In addition to confirming themes identified in focus groups, faith leaders described an openness to research partnerships between the university and faith communities and considerations for the formation of these partnerships. Faith leaders noted the importance of finding common ground with researchers, establishing and maintaining trusting relationships, and committing to open, bidirectional communication.

Drug resistance in acute lymphoblastic leukemia (ALL) remains a major problem warranting new treatment strategies. Wnt/catenin signaling is critical for the self-renewal of normal hematopoietic progenitor cells. Deregulated Wnt signaling is evident in chronic and acute myeloid leukemia; however, little is known about ALL. Differential interaction of catenin with either the Kat3 coactivator CREBBP (CREB-binding protein (CBP)) or the highly homologous EP300 (p300) is critical to determine divergent cellular responses and provides a rationale for the regulation of both proliferation and differentiation by the Wnt signaling pathway. Usage of the coactivator CBP by catenin leads to transcriptional activation of cassettes of genes that are involved in maintenance of progenitor cell self-renewal. However, the use of the coactivator p300 leads to activation of genes involved in the initiation of differentiation. ICG-001 is a novel small-molecule modulator of Wnt/catenin signaling, which specifically binds to the N-terminus of CBP and not p300, within amino acids 1–110, thereby disrupting the interaction between CBP and catenin. Here, we report that selective disruption of the CBP/β- and γ-catenin interactions using ICG-001 leads to differentiation of pre-B ALL cells and loss of self-renewal capacity. Survivin, an inhibitor-of-apoptosis protein, was also downregulated in primary ALL after treatment with ICG-001. Using chromatin immunoprecipitation assay, we demonstrate occupancy of the survivin promoter by CBP that is decreased by ICG-001 in primary ALL. CBP mutations have been recently identified in a significant percentage of ALL patients, however, almost all of the identified mutations reported occur C-terminal to the binding site for ICG-001. Importantly, ICG-001, regardless of CBP mutational status and chromosomal aberration, leads to eradication of drug-resistant primary leukemia in combination with conventional therapy in vitro and significantly prolongs the survival of NOD/SCID mice engrafted with primary ALL. Therefore, specifically inhibiting CBP/catenin transcription represents a novel approach to overcome relapse in ALL.

Dynamic regulation of leukocyte population size and activation state is crucial for an effective immune response. In malaria, Plasmodium parasites elicit robust host expansion of macrophages and monocytes, but the underlying mechanisms remain unclear. Here we show that myeloid expansion during P. chabaudi infection is dependent upon both CD4+ T cells and the cytokine Macrophage Colony Stimulating Factor (MCSF). Single-cell RNA-Seq analysis on antigen-experienced T cells revealed robust expression of Csf1, the gene encoding MCSF, in a sub-population of CD4+ T cells with distinct transcriptional and surface phenotypes. Selective deletion of Csf1 in CD4+ cells during P. chabaudi infection diminished proliferation and activation of certain myeloid subsets, most notably lymph node-resident CD169+ macrophages, and resulted in increased parasite burden and impaired recovery of infected mice. Depletion of CD169+ macrophages during infection also led to increased parasitemia and significant host mortality, confirming a previously unappreciated role for these cells in control of P. chabaudi. This work establishes the CD4+ T cell as a physiologically relevant source of MCSF in vivo; probes the complexity of the CD4+ T cell response during type 1 infection; and delineates a novel mechanism by which T helper cells regulate myeloid cells to limit growth of a blood-borne intracellular pathogen., Author Summary Malaria, caused by Plasmodium parasites, places a huge disease burden on humankind. Efforts to develop an effective vaccine for this pathogen are hampered by a poor understanding of the kinds of immune responses needed for protection. When infected with Plasmodium, humans and other mammalian hosts develop greatly increased numbers of certain white blood cells called myeloid cells, but the extent to which this expansion is important for fighting infection is unknown, as are the factors that regulate it. In this work, we show that expansion of myeloid cells during malaria is critical for control of parasite replication and host recovery. Myeloid expansion and control of infection require production of the signaling protein Macrophage Colony Stimulating Factor (MCSF) by multiple sources, including CD4+ T cells, which had not previously been known to make this protein in a physiological setting. This study reveals a new mechanism through which immune cells cooperate to control malaria, and may guide future attempts to generate protective immune responses against this devastating pathogen.

Duchenne muscular dystrophy (DMD) is a lethal, X-linked recessive disease affecting 1 in 3,500 newborn boys for which there is no effective treatment or cure. One novel strategy that has therapeutic potential for DMD is inhibition of myostatin, a negative regulator of skeletal muscle mass that may also promote fibrosis. Therefore, our goal in this study was to evaluate systemic myostatin inhibition in the golden retriever model of DMD (GRMD). GRMD canines underwent liver-directed gene transfer of a self-complementary adeno-associated virus type 8 vector designed to express a secreted dominant-negative myostatin peptide (n = 4) and were compared with age-matched, untreated GRMD controls (n = 3). Dogs were followed with serial magnetic resonance imaging (MRI) for 13 months to assess cross-sectional area and volume of skeletal muscle, then euthanized so that tissue could be harvested for morphological and histological analysis. We found that systemic myostatin inhibition resulted in increased muscle mass in GRMD dogs as assessed by MRI and confirmed at tissue harvest. We also found that hypertrophy of type IIA fibers was largely responsible for the increased muscle mass and that reductions in serum creatine kinase and muscle fibrosis were associated with long-term myostatin inhibition in GRMD. This is the first report describing the effects of long-term, systemic myostatin inhibition in a large-animal model of DMD, and we believe that the simple and effective nature of our liver-directed gene-transfer strategy makes it an ideal candidate for evaluation as a novel therapeutic approach for DMD patients.

The tension between exploitation of the best options and exploration of alternatives is a ubiquitous problem that all organisms face. To examine this trade-off across species, pigeons and people were trained on an eight-armed bandit task in which the options were rewarded on a variable interval (VI) schedule. At regular intervals, each option's VI changed, thus encouraging dynamic increases in exploration in response to these anticipated changes. Both species showed sensitivity to the payoffs that was often well modeled by Luce's (1963) decision rule. For pigeons, exploration of alternative options was driven by experienced changes in the payoff schedules, not the beginning of a new session, even though each session signaled a new schedule. In contrast, people quickly learned to explore in response to signaled changes in the payoffs.

This paper describes a delta-sigma (DeltaSigma) digital-to-analog converter (DAC) architecture that combines a polyphase decomposition of the interpolation filter and a time-interleaved error-feedback DeltaSigma modulator. Noise-shaped oversampling is achieved while clocking the digital circuitry at the Nyquist rate. The design of a third-order 4-bit modulator with eight times oversampling using the architecture is presented. Results from a prototype current-DAC driven by a VHDL simulation of the digital design at 2.66 GHz show that 56-dB linearity is achievable in 90-nm CMOS within a 1-V supply over a 155-MHz signal bandwidth making the architecture suitable for emerging ultra-wide-band and 60-GHz radio applications.

A small form-factor 60-GHz SiGe BiCMOS radio with two antennas-in-package is presented. The fully-integrated feature-rich transceiver provides a complete RF solution for mobile WiGig/IEEE 802.11ad applications.

In the first phase of this research, we conducted, audio‐recorded, and transcribed seven focus groups with more than 50 English‐ or Spanish‐speaking women of childbearing age. Qualitative analysis revealed the following themes: (1) expectation that participation would involve relationships based on trust that is built over time and impacted by cultural factors; (2) perceived characteristics of research staff that would help facilitate the development of trusting relationships; (3) perceptions about the location of the visits that may affect trust; (4) perceptions of a research study and trust for the institution conducting the study may affect trust; (5) connecting the study to larger communities, including faith communities, could affect trust and willingness to participate. In the second phase of this research, we conducted, recorded, transcribed, and analyzed interviews with leaders from diverse faith communities to explore the potential for research partnerships between researchers and faith communities. In addition to confirming themes identified in focus groups, faith leaders described an openness to research partnerships between the university and faith communities and considerations for the formation of these partnerships. Faith leaders noted the importance of finding common ground with researchers, establishing and maintaining trusting relationships, and committing to open, bidirectional communication.

In humans, immunity to Plasmodium sp. generally takes the form of protection from symptomatic malaria (i.e., 'clinical immunity') rather than infection ('sterilizing immunity'). In contrast, mice infected with Plasmodium develop sterilizing immunity, hindering progress in understanding the mechanistic basis of clinical immunity. Here we present a novel model in which mice persistently infected with P. chabaudi exhibit limited clinical symptoms despite sustaining patent parasite burdens for many months. Characterization of immune responses in persistently infected mice revealed development of CD4+ T cell exhaustion, increased production of IL-10, and expansion of B cells with an atypical surface phenotype. Additionally, persistently infected mice displayed a dramatic increase in circulating nonclassical monocytes, a phenomenon that we also observed in humans with both chronic Plasmodium exposure and asymptomatic infection. Following pharmacological clearance of infection, previously persistently infected mice could not control a secondary challenge, indicating that persistent infection disrupts the sterilizing immunity that typically develops in mouse models of acute infection. This study establishes an animal model of asymptomatic, persistent Plasmodium infection that recapitulates several central aspects of the immune response in chronically exposed humans. As such, it provides a novel tool for dissection of immune responses that may prevent development of sterilizing immunity and limit pathology during infection.

The bandwidth limitation of existing backplanes has become an obstacle to meeting the increasing demand for high-data-rate wireline transmission. In order to compensate for this limitation, TX pre-emphasis, RX continuous-time linear equalizer (CTLE) and DFE are necessary [1,2]. This work presents a 4-lane transceiver implemented in 40nm CMOS technology that operates over a wide range of data rates from 1 to 12Gb/s (48Gb/s aggregated) using NRZ coding. The supply voltages are 0.9V and 1.8V. An algorithm is developed to adapt the CTLE and DFE to cancel the channel ISI. No inductors are used in the design and ring oscillators are used for both the TX and RX clock generation. This provides a wide frequency-tuning range, small layout area, and high design portability. With extensive use of digital programmability this transceiver is capable of meeting specifications of different standards, such as PCIe, SATA, and 1 to 10Gb/s Ethernet.

OBJECTIVE: During patient care, it is critical to identify the glioma patients who are experiencing suicidal ideation among those who present with elevated levels of psychological distress, so appropriate interventions can be implemented. The aim of this study was to determine the factors that differentiated adult glioma patients with possible suicidal ideation from those without suicidal ideation among patients experiencing psychological distress. METHODS: 317 adult patients with WHO Grade II-IV glioma completed a psychosocial questionnaire comprised of several measures: Brief Symptom Inventory-18 (BSI-18) on general psychological distress, Patient Health Questionnaire-9 on depressive symptoms, General Anxiety Disorder-7 on anxiety symptoms, Revised Schwartz Cancer Fatigue Scale on fatigue, and CCSS Neurocognitive Questionnaire on cognitive symptoms. Patients with clinically elevated levels of psychological distress were identified, as determined by a BSI-18 Total T Score ≥ 50 (per Recklitis, 2007). Possible suicidal ideation was identified by endorsement of a positive response to BSI-18 item "thoughts of ending your life.“ T-tests, chi-square tests, and regression were utilized to identify the factors that distinguished the patients who endorsed possible suicidal ideation from those who did not, among the subset of patients with clinically elevated distress levels. RESULTS: 116 patients (36.6%) endorsed clinically significant distress levels. Of these, 17 patients (14.7%) endorsed possible suicidal ideation. Significantly higher levels of depression, anxiety, overall fatigue, emotional fatigue, emotional lability, task inefficiency, and memory concerns (p < .01) distinguished the patients with suicidal ideation. No medical characteristics (e.g., tumor location, grade, KPS, chemotherapy) or demographics (e.g., age, gender) significantly differentiated those with suicidal ideation from those without. CONCLUSION: The rates of clinically elevated psychological distress and potential suicidal ideation were determined in a large neuro-oncology clinic. Several psychosocial factors including fatigue and cognitive difficulties differentiated patients with possible suicidal ideation from those without, rather than tumor, treatment, or demographic characteristics.

Calpain activation has been implicated in the disease pathology of Duchenne muscular dystrophy. Inhibition of calpain has been proposed as a promising therapeutic target, which could lessen the protein degradation and prevent progressive fibrosis. At the same time, there are conflicting reports as to whether elevation of calpastatin, an endogenous calpain inhibitor, alters pathology. We compared the effects of pharmacological calpain inhibition in the mdx mouse using leupeptin and a proprietary compound (C101) that linked the inhibitory portion of leupeptin to carnitine (to increase uptake into muscle). Administration of C101 for 4 wk did not improve muscle histology, function, or serum creatine kinase levels in mdx mice. Mdx mice injected daily with leupeptin (36 mg/kg) for 6 mo also failed to show improved muscle function, histology, or creatine kinase levels. Biochemical analysis revealed that leupeptin administration caused an increase in m-calpain autolysis and proteasome activity, yet calpastatin levels were similar between treated and untreated mdx mice. These data demonstrate that pharmacological inhibition of calpain is not a promising intervention for the treatment of Duchenne muscular dystrophy due to the ability of skeletal muscle to counter calpain inhibitors by increasing multiple degradative pathways.

In a previous study investigating the effects of low temperature on skeletal muscle differentiation, we demonstrated that C2C12 mouse myoblasts cultured at 30°C do not express myogenin, a myogenic regulatory factor (MRF), or fuse into multinucleated myotubes. At this low temperature, the myoblasts continuously express Id3, a negative regulator of MRFs, and do not upregulate muscle-specific microRNAs. In this study, we examined if insulin-like growth factor-I (IGF-I) and a stable form of vitamin C (L-ascorbic acid phosphate) could alleviate the low temperature-induced inhibition of myogenic differentiation in C2C12 cells. Although the addition of either IGF-I or vitamin C alone could promote myogenin expression in C2C12 cells at 30°C, elongated multinucleated myotubes were not formed unless both IGF-I and vitamin C were continuously administered. In human skeletal muscle cells, low temperature-induced blockage of myogenic differentiation was also ameliorated by exogenous IGF-I and vitamin C. In addition, we demonstrated that satellite cells of IGF-I overexpressing transgenic mice in single-fiber culture expressed myogenin at a higher level than those of wild-type mice at 30°C. This study suggests that body temperature plays an important role in myogenic differentiation of endotherms, but the sensitivity to low temperature could be buffered by certain factors in vivo, such as IGF-I and vitamin C.

CCN1 is a matricellular protein that activates many genes related to wound healing and tissue remodeling in fibroblasts, but its effect on epithelial cells remains unclear. This study examined the role of CCN1 in epithelial wound healing using rat gastric epithelial cells and rat stomach ulcer as in vitro and in vivo models, respectively. We found that CCN1 expression is highly upregulated in the epithelial cells adjacent to a wound and remains high until the wound is healed. Upregulation of CCN1 activates a transient epithelial-mesenchymal transition in the epithelial cells at the migrating front and drives wound closure. Once the wound is healed, these epithelial cells and their progeny can resume their original epithelial phenotype. We also found that CCN1-induced E-cadherin loss is not due to transcriptional regulation but rather protein degradation due to the collapse of adherens junctions, which is contributed by beta-catenin translocation. CCN1-activated integrin-linked kinase mediates this process. Finally, our in vivo study showed that locally neutralizing CCN1 drastically impairs wound closure, whereas local injection of recombinant CCN1 protein induces expression of vimentin and smooth muscle alpha-actin in normal gastric mucosal epithelial cells and accelerates re-epithelialization during ulcer healing. In conclusion, our study indicates that CCN1 can induce reversible epithelial-mesenchymal transition, and this feature may have great value for clinical wound healing.