A Novel Probability-Based Logic-Locking Technique: ProbLock.

Integrated circuit (IC) piracy and overproduction are serious issues that threaten the security and integrity of a system. Logic locking is a type of hardware obfuscation technique where additional key gates are inserted into the circuit. Only the correct key can unlock the functionality of that circuit; otherwise, the system produces the wrong output. In an effort to hinder these threats on ICs, we have developed a probability-based logic-locking technique to protect the design of a circuit. Our proposed technique, called "ProbLock", can be applied to both combinational and sequential circuits through a critical selection process. We used a filtering process to select the best location of key gates based on various constraints. Each step in the filtering process generates a subset of nodes for each constraint. We also analyzed the correlation between each constraint and adjusted the strength of the constraints before inserting key gates. We tested our algorithm on 40 benchmarks from the ISCAS '85 and ISCAS '89 suites. We evaluated ProbLock against a SAT attack and measured how long the attack took to successfully generate a key value. The SAT attack took longer for most benchmarks using ProbLock which proves viable security in hardware obfuscation.

New Insights into the Ultrastructure of Bioapatite After Partial Dissolution: Based on Whale Rostrum, the Densest Bone.

Mineral particles in bone are interlaced with collagen fibrils, hindering the investigation of bioapatite crystallites (BAp). This study utilized a special whale rostrum (the most highly mineralized bone ever recorded) to measure the crystallites of bone BAp via long-term dissolution in water. The BAp in the rostrum has a low solubility (6.7 ppm Ca and 3.8 ppm P after 150 days dissolution) as well as in normal bones, which leads to its Ksp value of ~10-53. Atomic force microscopy results show tightly compacted mineral crystallites and confirm the low amount of collagen in the rostrum. Additionally, the mineral crystallites demonstrate irregular plate-like shapes with variable sizes. The small crystallites (~11 × 24 nm) are easily detached from BAp prisms, compared with the large crystallites (~50 nm). Moreover, various orientations of crystallites are observed on the edge of the prisms, which suggest a random direction of mineral growth. Furthermore, these plate-like crystallites prefer to be stacked layer by layer under weak regulation from collagen. The morphology of rostrum after dissolution provides new insights into the actual morphology of BAp crystallites.

Neuronal Protein 3.1 Deficiency Leads to Reduced Cutaneous Scar Collagen Deposition and Tensile Strength due to Impaired Transforming Growth Factor-ß1 to -ß3 Translation.

Neuronal protein 3.1 (P311), a conserved RNA-binding protein, represents the first documented protein known to stimulate transforming growth factor (TGF)-ß1 to -ß3 translation in vitro and in vivo. Because TGF-ßs play critical roles in fibrogenesis, we initiated efforts to define the role of P311 in skin scar formation. Here, we show that P311 is up-regulated in skin wounds and in normal and hypertrophic scars. Genetic ablation of p311 resulted in a significant decrease in skin scar collagen deposition. Lentiviral transfer of P311 corrected the deficits, whereas down-regulation of P311 levels by lentiviral RNA interference reproduced the deficits seen in P311-/- mice. The decrease in collagen deposition resulted in scars with reduced stiffness but also reduced scar tensile strength. In vitro studies using murine and human dermal fibroblasts showed that P311 stimulated TGF-ß1 to -ß3 translation, a process that involved eukaryotic translation initiation factor 3 subunit b as a P311 binding partner. This resulted in increased TGF-ß levels/activity and increased collagen production. In addition, P311 induced dermal fibroblast activation and proliferation. Finally, exogenous TGF-ß1 to -ß3, each restituted the normal scar phenotype. These studies demonstrate that P311 is required for the production of normal cutaneous scars and place P311 immediately up-stream of TGF-ßs in the process of fibrogenesis. Conditions that decrease P311 levels could result in less tensile scars, which could potentially lead to higher incidence of dehiscence after surgery.

Evidence Supporting a Lymphatic Endothelium Origin for Angiomyolipoma, a TSC2(-) Tumor Related to Lymphangioleiomyomatosis.

Angiomyolipoma (AML) is a tumor closely related to lymphangioleiomyomatosis (LAM). Both entities are characterized by the proliferation of smooth muscle actin and melanocytic glycoprotein 100 (recognized by antibody HMB-45)-positive spindle-shaped and epithelioid cells. AML and LAM are etiologically linked to mutations in the tsc2 and tsc1 genes in the case of LAM. These genes encode the proteins tuberous sclerosis complex (TSC)-1 and TSC2, which are directly involved in suppressing the mechanistic target of rapamycin cell growth signaling pathway. Although significant progress has been made in characterizing and pharmacologically slowing the progression of AML and LAM with rapamycin, our understanding of their pathogenesis lacks an identified cell of origin. We used an AML-derived cell line to determine whether TSC2 restitution brings about the cell type from which AML arises. We found that AML cells express lymphatic endothelial cell markers consistent with lymphatic endothelial cell precursors in vivo and in vitro. Moreover, on TSC2 correction, AML cells mature into adult lymphatic endothelial cells and have functional attributes characteristic of this cell lineage, suggesting a lymphatic endothelial cell of origin for AML. These effects are dependent on TSC2-mediated mechanistic target of rapamycin inactivation. Finally, we demonstrate the in vitro effectiveness of norcantharidin, a lymphangiogenesis inhibitor, as a potential co-adjuvant therapy in the treatment of AML.

A method for efficient expression of Pseudomonas aeruginosa alginate lyase in Pichia pastoris.

As an eco-friendly biocatalyst for alginate hydrolysis, bacteria-derived alginate lyase (AlgL) has been widely used in research and industries to produce oligosaccharides. However, the cost of AlgL enzyme production remains high due to the low expression and difficulty in purification from bacterial cells. In this study we report an effective method to overexpress the Pseudomonas aeruginosa AlgL (paAlgL) enzyme in Pichia pastoris. Fused with a secretory peptide, the recombinant paAlgL was expressed extracellularly and purified from the culture supernatant through a simple process. The purified recombinant enzyme is highly specific for alginate sodium with a maximal activity of 2,440 U/mg. The enzymatic activity remained stable below 45°C and at pH between 4 and 10. The recombinant paAlgL was inhibited by Zn(2+), Cu(2+), and Fe(2+) and promoted by Co(2+) and Ca(2+). Interestingly, we also found that the recombinant paAlgL significantly enhanced the antimicrobial activity of antibiotics ampicillin and kanamycin against Pseudomonas aeruginosa. Our results introduce a method for efficient AlgL production, the characterization, and a new feature of the recombinant paAlgL as an enhancer of antibiotics against Pseudomonas aeruginosa.

Novel RNA-binding protein P311 binds eukaryotic translation initiation factor 3 subunit b (eIF3b) to promote translation of transforming growth factor ß1-3 (TGF-ß1-3).

P311, a conserved 8-kDa intracellular protein expressed in brain, smooth muscle, regenerating tissues, and malignant glioblastomas, represents the first documented stimulator of TGF-ß1-3 translation in vitro and in vivo. Here we initiated efforts to define the mechanism underlying P311 function. PONDR® (Predictor Of Naturally Disordered Regions) analysis suggested and CD confirmed that P311 is an intrinsically disordered protein, therefore requiring an interacting partner to acquire tertiary structure and function. Immunoprecipitation coupled with mass spectroscopy identified eIF3 subunit b (eIF3b) as a novel P311 binding partner. Immunohistochemical colocalization, GST pulldown, and surface plasmon resonance studies revealed that P311-eIF3b interaction is direct and has a Kd of 1.26 µm. Binding sites were mapped to the non-canonical RNA recognition motif of eIF3b and a central 11-amino acid-long region of P311, here referred to as eIF3b binding motif. Disruption of P311-eIF3b binding inhibited translation of TGF-ß1, 2, and 3, as indicated by luciferase reporter assays, polysome fractionation studies, and Western blot analysis. RNA precipitation assays after UV cross-linking and RNA-protein EMSA demonstrated that P311 binds directly to TGF-ß 5'UTRs mRNAs through a previously unidentified RNA recognition motif-like motif. Our results demonstrate that P311 is a novel RNA-binding protein that, by interacting with TGF-ßs 5'UTRs and eIF3b, stimulates the translation of TGF-ß1, 2, and 3.

The effect of wilderness and medical training on injury and altitude preparedness among backcountry hikers in Rocky Mountain National Park.

BACKGROUND: The purpose of this study was to document the correlation between medical and wilderness training with levels of preparedness for acute mountain sickness (AMS), illness, and injury among backcountry hikers. METHODS: We conducted a cross-sectional, convenience survey in Rocky Mountain National Park in July and August 2015. The study group consisted of 380 hikers who completed a written survey that collected information about demographics, wilderness experience, altitude experience, hiking equipment, communications devices, and trip planning. RESULTS: Factors such as wilderness training (wilderness first aid [WFA], wilderness first responder [WFR], or wilderness emergency medical technician [WEMT]), wilderness experience, and altitude experience all affected hikers' emergency preparedness. Respondents with medical training were more prepared to avoid or respond to AMS (62.3% vs. 34.3% [P<0.001]). They were also more prepared to avoid or manage injury/illness than hikers without medical training (37.7% vs. 20.7% [P=0.003]). Participants with wilderness training were more likely to be prepared to avoid or respond to AMS (52.3% vs. 36.8% [P=0.025]) but not significantly more likely to be prepared to manage illness/injury (31.8% vs. 22.0% [P<0.11]). Adjusting for experience, wilderness training, age, and gender, we found that medical training was associated with increased preparedness for AMS (OR 2.72; 95% CI 1.51-4.91) and injury/illness (OR 2.71; 95% CI 1.5-4.89). CONCLUSION: Medically trained hikers were more likely to be prepared to avoid or manage AMS, medical emergencies, and injuries than their non-medically trained counterparts. Wilderness training increased hikers' preparedness for AMS but did not significantly alter preparedness for illness/injury.

In pulmonary lymphangioleiomyomatosis expression of progesterone receptor is frequently higher than that of estrogen receptor.

Lymphangioleiomyomatosis (LAM) of the lung is a rare low-grade malignancy affecting primarily women of childbearing age. LAM is characterized by the proliferation of SMA and HMB-45 positive spindle-shaped and epithelioid cells throughout the lung in the form of discrete lesions causing cystic destruction and ultimately respiratory insufficiency. LAM occurs sporadically or in patients with tuberous sclerosis complex (TSC) and is etiologically linked to mutations in the TSC1 and TSC2 genes. Although LAM cells are known to express estrogen and progesterone receptors (ER and PR, respectively), their respective expression level was never determined. Therefore, here we measured the immunohistochemical expression of ERs and PRs in a large series of pulmonary LAM cases using the Aperio Spectrum Analysis Platform. Our case series comprised open lung biopsy specimens from 20 LAM patients and lungs explanted during the course of lung transplant from 24 patients. All cases were positive for ER and PR. PR expression was statistically significantly higher than ER in 80 % of the biopsies while ER predominated only in one case. Specimens from explanted cases of LAM had relatively fewer PR-positive nuclei. As a result, PR expression was significantly higher than ER in 38 % of the cases, whereas ER predominated in 33 %. Overall, PR expression predominated in 57 % of cases and ER in 21 %. These data indicate that PR frequently prevails over ER in pulmonary LAM. LAM is unusual in its high PR/ER ratio; other female neoplasms show a definite prevalence of ER. Our findings therefore warrant further study of PR function in LAM.