An Efficient Authenticated Key Exchange from Random Self-Reducibility on CSIDH

SIDH and CSIDH are key exchange protocols based on isogenies and conjectured to be quantum-resistant. Since the protocols are similar to the classical Diffie–Hellman, they are vulnerable to the man-in-the-middle attack. A key exchange which is resistant to such an attack is called an authenticated key exchange (AKE), and many isogeny-based AKEs have been proposed. However, the parameter sizes of the existing schemes should be large since they all have relatively large security losses in security proofs. This is partially because the random self-reducibility of isogeny-based decisional problems has not been proved yet. In this paper, we show that the computational problem and the gap problem of CSIDH are random self-reducible. A gap problem is a computational problem given access to the corresponding decision oracle. Moreover, we propose a CSIDH-based AKE with small security loss, following the construction of Cohn-Gordon et al. in CRYPTO 2019, as an application of the random self-reducibility of the gap problem of CSIDH. Our AKE is proved to be the fastest CSIDH-based AKE when we aim at 110-bit security level

Visualization of intrathoracically disseminated solid tumors in mice with optical imaging by telomerase-specific amplification of a transferred green fluorescent protein gene

Currently available methods for detection of tumors in vivo such as X-ray, computed tomography, and ultrasonography are noninvasive and have been well studied; the images, however, are not specific for tumors. Direct optical imaging of tumor cells in vivo that can clearly distinguish them from surrounding normal tissues may be clinically useful. Here, we describe a new approach to visualizing tumors whose fluorescence can be detected using tumor-specific replication-competent adenovirus (OBP-301, Telomelysin) in combination with Ad-GFP, a replication-deficient adenovirus expressing green fluorescent protein (GFP). Human telomerase reverse transcriptase is the catalytic subunit of telomerase, which is highly active in cancer cells but quiescent in most normal somatic cells. We constructed an adenovirus 5 vector in which the human telomerase reverse transcriptase promoter element drives expression of E1A and E1B genes linked with an internal ribosome entry site and showed that OBP-301 replicated efficiently in human cancer cells, but not in normal cells such as human fibroblasts. When the human lung and colon cancer cell lines were infected with Ad-GFP at a low multiplicity of infection, GFP expression could not be detected under a fluorescence microscope; in the presence of OBP-301, however, Ad-GFP replicated in these tumor cells and showed strong green signals. In contrast, coinfection with OBP-301 and Ad-GFP did not show any signals in normal cells such as fibroblasts and vascular endothelial cells. We also found that established subcutaneous tumors could be visualized after intraturnoral injection of OBP-301 and Ad-GFP. A549 human lung tumors and SW620 human colon tumors transplanted into BALB/c nu/nu mice were intraturnorally injected with 8 X 10(5) plaque-forming units of Ad-GFP in combination with 8 X 106 plaque-forming units of OBP-301. Within 3 days of treatment, the fluorescence of the expressed GFP became visible by a three-chip color cooled charged-coupled device camera in these tumors, whereas intraturnoral injection of Ad-GFP alone could not induce GFP fluorescence. Moreover, intrathoracic administration of Ad-GFP and OBP-301 could visualize disseminated A549 tumor nodules in mice after intrathoracic implantation. Our results indicate that intratumoral or intrathoracic injection of Ad-GFP in combination with OBP-301 might be a useful diagnostic method that provides a foundation for future clinical application

Species identification, antifungal susceptibility, and clinical feature association of Aspergillus section Nigri isolates from the lower respiratory tract

Species of Aspergillus section Nigri are generally identified by molecular genetics approaches, whereas in clinical practice, they are classified as A. niger by their morphological characteristics. This study aimed to investigate whether the species of Aspergillus section Nigri isolated from the respiratory tract vary depending on clinical diagnosis. Forty-four Aspergillus section Nigri isolates isolated from the lower respiratory tracts of 43 patients were collected from February 2012 to January 2017 at the National Hospital Organization (NHO) Tokyo National Hospital. Species identification was carried out based on β-tubulin gene analysis. Drug susceptibility tests were performed according to the Clinical and Laboratory Standards Institute (CLSI) M38 3rd edition, and the clinical characteristics were retrospectively reviewed. A. welwitschiae was isolated most frequently, followed by A. tubingensis. More than half of the A. tubingensis isolates exhibited low susceptibility to azoles in contrast to only one A. welwitschiae isolate. Approximately three quarters of the patients from whom A. welwitschiae was isolated were diagnosed with colonization, whereas more than half the patients from whom A. tubingensis was isolated were diagnosed with chronic pulmonary aspergillosis (CPA). More attention needs to be given to the drug choice for patients with CPA with Aspergillus section Nigri infection because A. tubingensis, which was found to be frequently azole-resistant, was the most prevalent in these patients

Insights into Land Plant Evolution Garnered from the Marchantia polymorpha Genome.

The evolution of land flora transformed the terrestrial environment. Land plants evolved from an ancestral charophycean alga from which they inherited developmental, biochemical, and cell biological attributes. Additional biochemical and physiological adaptations to land, and a life cycle with an alternation between multicellular haploid and diploid generations that facilitated efficient dispersal of desiccation tolerant spores, evolved in the ancestral land plant. We analyzed the genome of the liverwort Marchantia polymorpha, a member of a basal land plant lineage. Relative to charophycean algae, land plant genomes are characterized by genes encoding novel biochemical pathways, new phytohormone signaling pathways (notably auxin), expanded repertoires of signaling pathways, and increased diversity in some transcription factor families. Compared with other sequenced land plants, M. polymorpha exhibits low genetic redundancy in most regulatory pathways, with this portion of its genome resembling that predicted for the ancestral land plant. PAPERCLIP

A Surface Study of Amorphous Nickel-Base Alloys Immersed in Liquid Sodium Contaminated with Impurities

Amorphous nickel-phosphorus alloys containing Cr, Mo, W, Al and/or Si were immersed for about 600 hours at 200℃ in liquid sodium which simulated a coolant of the fast breeder reactor by dissolving less than 700 ppm of Zn, Ag, Sb, Mn, Co and Cs. Surfaces of alloys were examined by using X-ray photoelectron spectroscopy and energy dispersive X-ray analysis. Only zinc and silver were trapped by the alloys. The trapped zinc distributed at least to the 3-4μm deep surface region, while silver was found mainly in the depth less than 100 nm. The high concentration of nickel in the alloy was preferable for trapping zinc. As a silver getter, alloying with chromium and/or molybdenum favored but nickel was detrimental. The alloys of high chromium contents were not effective because of formation of a surface film of chromium compounds which prevented direct contact of the alloys with liquid sodium

A Case of Pulmonary Pleomorphic Carcinoma With Renal Metastasis

A 62-year-old man was referred to our hospital for an axillary mass. Computed tomography (CT) revealed a right axillary tumor and a left renal tumor. Needle biopsies of lung tumor and renal tumor were performed, but a definite diagnosis was impossible. Because his performance status worsened and the lung tumor grew day by day, chemotherapy with gemcitabine and cisplatin was started without definite diagnosis. However, the chemotherapy could not be continued because of interstitial pneumonia and the patient died because of the progression of disease. The final histopathologic diagnosis was pulmonary pleomorphic carcinoma based on immunohistochemical staining

Escala y talla de primera madurez gonadal del lenguado de ojo grande Hippoglossina macrops (Steindachner, 1876) de la zona comprendida entre Puerto Pizarro y Huarmey (03°30° L.S. y 10° L.S.)

TesisEscala y talla de primera madurez gonadal del lenguado de ojo grande Hippoglossina macrops (Steindachner, 1876) de la zona comprendida entre Puerto Pizarro y Huarmey (03°30° L.S. y 10° L.S.