Hierarchical Clustering via Single and Complete Linkage Using Fully Homomorphic Encryption.

Hierarchical clustering is a widely used data analysis technique. Typically, tools for this method operate on data in its original, readable form, raising privacy concerns when a clustering task involving sensitive data that must remain confidential is outsourced to an external server. To address this issue, we developed a method that integrates Cheon-Kim-Kim-Song homomorphic encryption (HE), allowing the clustering process to be performed without revealing the raw data. In hierarchical clustering, the two nearest clusters are repeatedly merged until the desired number of clusters is reached. The proximity of clusters is evaluated using various metrics. In this study, we considered two well-known metrics: single linkage and complete linkage. Applying HE to these methods involves sorting encrypted distances, which is a resource-intensive operation. Therefore, we propose a cooperative approach in which the data owner aids the sorting process and shares a list of data positions with a computation server. Using this list, the server can determine the clustering of the data points. The proposed approach ensures secure hierarchical clustering using single and complete linkage methods without exposing the original data.

COVID-19 Testing and Diagnostics: A Review of Commercialized Technologies for Cost, Convenience and Quality of Tests.

Population-scale and rapid testing for SARS-CoV-2 continues to be a priority for several parts of the world. We revisit the in vitro technology platforms for COVID-19 testing and diagnostics-molecular tests and rapid antigen tests, serology or antibody tests, and tests for the management of COVID-19 patients. Within each category of tests, we review the commercialized testing platforms, their analyzing systems, specimen collection protocols, testing methodologies, supply chain logistics, and related attributes. Our discussion is essentially focused on test products that have been granted emergency use authorization by the FDA to detect and diagnose COVID-19 infections. Different strategies for scaled-up and faster screening are covered here, such as pooled testing, screening programs, and surveillance testing. The near-term challenges lie in detecting subtle infectivity profiles, mapping the transmission dynamics of new variants, lowering the cost for testing, training a large healthcare workforce, and providing test kits for the masses. Through this review, we try to understand the feasibility of universal access to COVID-19 testing and diagnostics in the near future while being cognizant of the implicit tradeoffs during the development and distribution cycles of new testing platforms.

Abnormal autonomic and associated brain activities during rest in autism spectrum disorder.

Autism spectrum disorders are associated with social and emotional deficits, the aetiology of which are not well understood. A growing consensus is that the autonomic nervous system serves a key role in emotional processes, by providing physiological signals essential to subjective states. We hypothesized that altered autonomic processing is related to the socio-emotional deficits in autism spectrum disorders. Here, we investigated the relationship between non-specific skin conductance response, an objective index of sympathetic neural activity, and brain fluctuations during rest in high-functioning adults with autism spectrum disorder relative to neurotypical controls. Compared with control participants, individuals with autism spectrum disorder showed less skin conductance responses overall. They also showed weaker correlations between skin conductance responses and frontal brain regions, including the anterior cingulate and anterior insular cortices. Additionally, skin conductance responses were found to have less contribution to default mode network connectivity in individuals with autism spectrum disorders relative to controls. These results suggest that autonomic processing is altered in autism spectrum disorders, which may be related to the abnormal socio-emotional behaviours that characterize this condition.

An automated, high-resolution phenotypic assay for adult Brugia malayi and microfilaria.

Brugia malayi are thread-like parasitic worms and one of the etiological agents of Lymphatic filariasis (LF). Existing anthelmintic drugs to treat LF are effective in reducing the larval microfilaria (mf) counts in human bloodstream but are less effective on adult parasites. To test potential drug candidates, we report a multi-parameter phenotypic assay based on tracking the motility of adult B. malayi and mf in vitro. For adult B. malayi, motility is characterized by the centroid velocity, path curvature, angular velocity, eccentricity, extent, and Euler Number. These parameters are evaluated in experiments with three anthelmintic drugs. For B. malayi mf, motility is extracted from the evolving body skeleton to yield positional data and bending angles at 74 key point. We achieved high-fidelity tracking of complex worm postures (self-occlusions, omega turns, body bending, and reversals) while providing a visual representation of pose estimates and behavioral attributes in both space and time scales.

Co and Fe doping effect on negative temperature coefficient characteristics of nano-grained NiMn2O4 thick films fabricated by aerosol-deposition.

Spinel structured highly dense NiMn2O4-based (NMO) negative temperature coefficient (NTC) thermistor thick films were fabricated by aerosol-deposition at room temperature. To enhance the thermistor B constant, which represents the temperature sensitivity of the NMO thermistor material, Co and Co-Fe doping was applied. In the case of single element doping of Co, 5 mol% doped NMO showed a high B constant of over 5000 K, while undoped NMO showed -4000 K. By doping Fe to the 5 mol% Co doped NMO, the B constant was more enhanced at over 5600 K. The aging effect on the NTC characteristics of Co doped and Fe-Co co-doped NMO thick film showed very stable resistivity-time characteristics because of the highly dense microstructure.

Involvement of the anterior cingulate and frontoinsular cortices in rapid processing of salient facial emotional information.

The anterior cingulate cortex (ACC) and frontoinsular cortex (FI) have been implicated in processing information across a variety of domains, including those related to attention and emotion. However, their role in rapid information processing, for example, as required for timely processing of salient stimuli, is not well understood. Here, we designed an emotional face priming paradigm and employed functional magnetic resonance imaging to elucidate their role in these mechanisms. Target faces with either neutral or fearful emotion were briefly primed by either neutral or fearful faces, or by blank ovals. The pregenual ACC and the FI, together with other regions, such as the amygdala, were preferentially activated in response to fearful face priming, suggesting that these regions are involved in the rapid processing of salient facial emotional information.

Scan4CFU: Low-cost, open-source bacterial colony tracking over large areas and extended incubation times.

A hallmark of bacterial populations cultured in vitro is their homogeneity of growth, where the majority of cells display identical growth rate, cell size and content. Recent insights, however, have revealed that even cells growing in exponential growth phase can be heterogeneous with respect to variables typically used to measure cell growth. Bacterial heterogeneity has important implications for how bacteria respond to environmental stresses, such as antibiotics. The phenomenon of antimicrobial persistence, for example, has been linked to a small subpopulation of cells that have entered into a state of dormancy where antibiotics are no longer effective. While methods have been developed for identifying individual non-growing cells in bacterial cultures, there has been less attention paid to how these cells may influence growth in colonies on a solid surface. In response, we have developed a low-cost, open-source platform to perform automated image capture and image analysis of bacterial colony growth on multiple nutrient agar plates simultaneously. The descriptions of the hardware and software are included, along with details about the temperature-controlled growth chamber, high-resolution scanner, and graphical interface to extract and plot the colony lag time and growth kinetics. Experiments were conducted using a wild type strain of Escherichia coli K12 to demonstrate the feasibility and operation of our setup. By automated tracking of bacterial growth kinetics in colonies, the system holds the potential to reveal new insights into understanding the impact of microbial heterogeneity on antibiotic resistance and persistence.

Influence of the COMT val(108/158)met polymorphism on continuous performance task indices.

The Continuous Performance Task (CPT) is a widely-used measure of sustained attention and impulsivity. Deficits in CPT performance have been found in several psychiatric disorders, such as Attention-Deficit/Hyperactivity Disorder (ADHD) and schizophrenia. Molecular genetic studies of CPT performance are currently limited and have generally revealed inconsistent findings. The current study tested the associations of the COMT val(108/158)met polymorphism with AX-CPT indices (i.e., omission and commission errors, d׳, and lnß), as well as the variability of these indices across blocks, in a sample of clinic-referred and non-referred children (N=380). We found significant associations between COMT and variability in the Signal Detection Theory (SDT) indices d׳ and lnß across blocks, as well as a statistical trend for association between COMT and commission errors. Higher externalizing psychopathology was associated with general impairment on AX-CPT performance, and for some indices (i.e., d׳ variability and lnß variability) the effect of COMT was stronger at higher levels of psychopathology. Our findings support the role of COMT in components of CPT performance and highlight the potential utility of using SDT indices, particularly in relation to variability in performance. Moreover, our results suggest that for some indices the effect of COMT is stronger at higher levels of externalizing psychopathology. Our study yields some preliminary insights regarding the neurobiology of CPT performance, which may elucidate the mechanisms by which specific genes confer risk for various cognitive deficits, as well as relevant disorders characterized by these deficits.

Tussilagone inhibits dendritic cell functions via induction of heme oxygenase-1.

Sesquiterpenoid tussilagone (TUS) has a variety of pharmacological activities, such as anti-oxidant, anti-cancer, and anti-inflammatory activities. In this study, we investigated the effects of TUS on dendritic cell (DC) functions and the underlying mechanisms. TUS inhibited lipopolysaccharide (LPS)-induced activation of DCs, as shown by decrease in surface molecule expression, cytokine production, cell migration, and allo-T cell activation. In addition, TUS inhibited LPS-induced activation of NF-κB, MAPKs, and IRF-3 signalings in DCs, although it did not directly affect kinase activities of IRAK1/4, TAK1, and IKK, which suggests that TUS might indirectly inhibit TLR signaling in DCs. As a critical mechanism, we showed that TUS activated heme oxygenase-1 (HO-1), which degrades heme to immunosuppressive products, such as carbon monoxide and bilirubin. HO-1 inhibitor reversed the inhibitory activity of TUS in DCs. In conclusion, this study suggests that TUS inhibits DC function through the induction of HO-1.

Preclinical efficacy and mechanisms of mesenchymal stem cells in animal models of autoimmune diseases.

Mesenchymal stem cells (MSCs) are present in diverse tissues and organs, including bone marrow, umbilical cord, adipose tissue, and placenta. MSCs can expand easily in vitro and have regenerative stem cell properties and potent immunoregulatory activity. They inhibit the functions of dendritic cells, B cells, and T cells, but enhance those of regulatory T cells by producing immunoregulatory molecules such as transforming growth factor-ß, hepatic growth factors, prostaglandin E2, interleukin-10, indolamine 2,3-dioxygenase, nitric oxide, heme oxygenase-1, and human leukocyte antigen-G. These properties make MSCs promising therapeutic candidates for the treatment of autoimmune diseases. Here, we review the preclinical studies of MSCs in animal models for systemic lupus erythematosus, rheumatoid arthritis, Crohn's disease, and experimental autoimmune encephalomyelitis, and summarize the underlying immunoregulatory mechanisms.

Preclinical and clinical studies on cytokine-induced killer cells for the treatment of renal cell carcinoma.

Renal cell carcinoma (RCC) is the most common malignancy of adult human kidney, which accounts for more than 2 % of all cancers. RCC generally does not respond well to conventional chemotherapy and radiotherapy. Cytokine-induced killer (CIK) cells are ex vivo activated lymphocytes with potent activity against various tumors and minimal side effects. Here, we summarize the data on preclinical and clinical efficacy of CIK cells for RCC treatment. Our preclinical data show that CIK cells have potent anti-tumor activity in vitro and in an in vivo nude mouse xenograft model. Clinical studies for the treatment of RCC patients indicate that CIK cell therapy can induce favorable responses with no serious side effects. These studies suggest that CIK cells may become a valuable strategy for the treatment of patients with RCC.

Functional neural correlates of attentional deficits in amnestic mild cognitive impairment.

Although amnestic mild cognitive impairment (aMCI; often considered a prodromal phase of Alzheimer's disease, AD) is most recognized by its implications for decline in memory function, research suggests that deficits in attention are present early in aMCI and may be predictive of progression to AD. The present study used functional magnetic resonance imaging to examine differences in the brain during the attention network test between 8 individuals with aMCI and 8 neurologically healthy, demographically matched controls. While there were no significant behavioral differences between groups for the alerting and orienting functions, patients with aMCI showed more activity in neural regions typically associated with the networks subserving these functions (e.g., temporoparietal junction and posterior parietal regions, respectively). More importantly, there were both behavioral (i.e., greater conflict effect) and corresponding neural deficits in executive control (e.g., less activation in the prefrontal and anterior cingulate cortices). Although based on a small number of patients, our findings suggest that deficits of attention, especially the executive control of attention, may significantly contribute to the behavioral and cognitive deficits of aMCI.

Bisabolangelone inhibits dendritic cell functions by blocking MAPK and NF-κB signaling.

Bisabolangelone (BISA), isolated from the roots of Angelica koreana, has many pharmacological activities, such as anti-tumor, anti-microbial, antioxidant, and anti-inflammatory activities. In this study, we investigated the anti-inflammatory mechanisms of BISA in dendritic cells (DCs), which play an essential role in innate and adaptive immune responses. BISA attenuated the production of pro-inflammatory cytokines including interleukin (IL)-12, IL-1ß, and tumor necrosis factor-alpha (TNF-α), migration to macrophage inflammatory protein-3 beta, and allo-T cell activating ability of DCs. In addition, BISA affected endocytosis of DCs. Molecular studies showed that BISA suppressed MAPK phosphorylation and nuclear translocation of NF-κB p50/p65. Taken together, our data suggest that BISA inhibited DC functions by blocking MAPK and NF-κB signaling.

Functional deficits of the attentional networks in autism.

Attentional dysfunction is among the most consistent observations of autism spectrum disorders (ASD). However, the neural nature of this deficit in ASD is still unclear. In this study, we aimed to identify the neurobehavioral correlates of attentional dysfunction in ASD. We used the Attention Network Test-Revised and functional magnetic resonance imaging to examine alerting, orienting, and executive control functions, as well as the neural substrates underlying these attentional functions in unmedicated, high-functioning adults with ASD (n = 12) and matched healthy controls (HC, n = 12). Compared with HC, individuals with ASD showed increased error rates in alerting and executive control, accompanied by lower activity in the mid-frontal gyrus and the caudate nucleus for alerting, and by the absence of significant functional activation in the anterior cingulate cortex (ACC) for executive control. In addition, greater behavioral deficiency in executive control in ASD was correlated with less functional activation of the ACC. These findings of behavioral and neural abnormalities in alerting and executive control of attention in ASD may suggest core attentional deficits, which require further investigation.

Synergic induction of human periodontal ligament fibroblast cell death by nitric oxide and N-methyl-D-aspartic acid receptor antagonist.

PURPOSE: Nitric oxide (NO) has been known as an important regulator of osteoblasts and periodontal ligament cell activity. This study was performed to investigate the relationship between NO-mediated cell death of human periodontal ligament fibroblasts (PDLFs) and N-methyl-D-aspartic acid (NMDA) receptor antagonist (+)-5-methyl-10, 11-dihydro-5H-dibenzo[a,d]cyclohepten-5, 10-imine hydrogen maleate (MK801). METHODS: Human PDLFs were treated with various concentrations (0 to 4 mM) of sodium nitroprusside (SNP) with or without 200 µM MK801 in culture media for 16 hours and the cell medium was then removed and replaced by fresh medium containing MTS reagent for cell proliferation assay. Western blot analysis was performed to investigate the effects of SNP on the expression of Bax, cytochrome c, and caspase-3 proteins. The differences for each value among the sample groups were compared using analysis of variance with 95% confidence intervals. RESULTS: In the case of SNP treatment, as a NO donor, cell viability was significantly decreased in a concentration-dependent manner. In addition, a synergistic effect was shown when both SNP and NMDA receptor antagonist was added to the medium. SNP treated PDLFs exhibited a round shape in culture conditions and were dramatically reduced in cell number. SNP treatment also increased levels of apoptotic marker protein, such as Bax and cytochrome c, and reduced caspase-3 in PDLFs. Mitogen-activated protein kinase signaling was activated by treatment of SNP and NMDA receptor antagonist. CONCLUSIONS: These results suggest that excessive production of NO may induce apoptosis and that NMDA receptor may modulate NO-induced apoptosis in PDLFs.

Dimensional overlap accounts for independence and integration of stimulus-response compatibility effects.

Extensive studies have been conducted to examine various attentional control effects that stem from stimulus-stimulus (S-S) and stimulus-response (S-R) incompatibility. Among these behavioral paradigms, the best-known are the Stroop effect, the Simon effect, and Posner's cue validity effect. In this study, we designed two behavioral tasks incorporating these effects (Simon-color-Stroop and Simon-spatial-Stroop) guided by a general framework of S-R ensemble, the dimensional overlap theory. We analyzed various attentional effects according to dimensional overlaps among S-S and S-R ensembles and their combinations. We found that behavioral performance was independently affected by various dimensional overlaps in the Simon-color-Stroop task, whereas different sources of dimensional overlap in the Simon-spatial-Stroop task interacted with each other. We argue that the dimensional overlap theory can be extended to serve as a viable unified theory that accounts for diverse attentional effects and their interactions and helps to elucidate neural networks subserving attentional control.

Cue contrast modulates the effects of exogenous attention on appearance.

Exogenous spatial attention can be automatically engaged by a cue presented in the visual periphery. To investigate the effects of exogenous attention, previous studies have generally used highly salient cues that reliably trigger attention. However, the cueing threshold of exogenous attention has been unexamined. We investigated whether the attentional effect varies with cue salience. We examined the magnitude of the attentional effect on apparent contrast [Carrasco, M., Ling, S., & Read, S. (2004). Attention alters appearance. Nature Neuroscience, 7(3), 308-313.] elicited by cues with negative Weber contrast between 6% and 100%. Cue contrast modulated the attentional effect, even at cue contrasts above the level at which observers can perfectly localize the cue; hence, the result is not due to an increase in cue visibility. No attentional effect is observed when the 100% contrast cue is presented after the stimuli, ruling out cue bias or sensory interaction between cues and stimuli as alternative explanations. A second experiment, using the same paradigm with high contrast motion stimuli gave similar results, providing further evidence against a sensory interaction explanation, as the stimuli and task were defined on a visual dimension independent from cue contrast. Although exogenous attention is triggered automatically and involuntarily, the attentional effect is gradual.