Osborn Waves: History and Significance

The Osborn wave is a deflection with a dome or hump configuration occurring at the R-ST junction (J point) on the ECG (Fig. 1). In the historical view, different names have been used for this wave in the medical literature, such as “camel-hump sign”, “late delta wave”, “hathook junction”, “hypothermic wave”, “J point wave”, “K wave”, “H wave” and “current of injury”.1 Although there is no definite consensus about terminology of this wave, either “Osborn wave” or “J wave” are the most commonly used names for this wave in the current clinical and experimental cardiology. The Osborn wave can be generally observed in hypothermic patients,1,2,3,4 however, other conditions have been reported to cause Osborn waves, such as hypercalcemia,5 brain injury,6 subarachnoid hemorrhage,7 cardiopulmonary arrest from oversedation,8 vasospastic angina,9 or idiopathic ventricular fibrillation.10,11,12 Our knowledge about the link between the Osborn waves and cardiac arrhythmias remains sparse and the arrhythmogenic potential of the Osborn waves is not fully understood. In this paper, we present a historic review of Osborn waves and discuss their clinical significance in the various clinical settings

Peirce’s Reception in Japan

In Japan, the number of investigations of Charles Sanders Peirce’s philosophy has recently increased. In this article, we can focus only on a few instances of the research movement in Japan that has put Peirce’s ideas at its center. However, even such a limited survey shows that Peirce’s work has affected various Japanese academic areas. In this paper we talk about three types of Japanese studies of Peirce’s pragmatism: discussions of Peirce’s theory of abduction, examinations of Peirce’s the..

The Absence of Prion-Like Infectivity in Mice expressing Prion Protein-Like Protein

Cellular prion protein, PrP^C, undergoes pathogenic structural conversion into the proteinase K (PK)-resistant isoform, PrP^Sc, to constitute a nucleic acid-free infectious agent, so called a prion. To determine whether a recently identified PrP-like protein, named PrPLP/Dpl, could also be transformed to a prion-like protein, we intracerebrally inoculated a mouse-adapted Fukuoka-1 prion into Ngsk and Zrch I mice either homozygously (Prnp^0/0) or heterozygously (Prnp^0/+) devoid of PrP^C. Only the former expressed PrPLP/Dpl ectopically in the brains, particularly in neurons. Ngsk Prnp^0/+ and Zrch I Prnp^0/+ mice similarly developed the disease. The diseased Ngsk Prnp0/+ mice transmitted the disease to the mice expressing PrP^C but not to the mice expressing PrPLP/Dpl, showing abundant accumulation of PrP^Sc but not PK-resistant PrPLP/Dpl in the brains. Moreover, the inoculated Ngsk Prnp^0/0 mice neither developed the disease nor produced any infectivity transmissible to PrPLP/Dpl-expressing mice. These results indicate that PrPLP/Dpl have no potential to undergo pathogenic conversion to form a prion-like infectious particle

Recent advances in cell-free PrPSc amplification technique.

The development of amplification technology for abnormal forms of prion protein in vitro has had a great impact on the field of prion research. This novel technology has generated new possibilities for understanding the molecular basis of prions and for developing an early diagnostic test for prion diseases. This review provides an overview of recent progress in cell-free PrPSc amplification techniques

Prion Disease Blood Test Using Immunoprecipitation and Improved Quaking-Induced Conversion

A key challenge in managing transmissible spongiform encephalopathies (TSEs) or prion diseases in medicine, agriculture, and wildlife biology is the development of practical tests for prions that are at or below infectious levels. Of particular interest are tests capable of detecting prions in blood components such as plasma, but blood typically has extremely low prion concentrations and contains inhibitors of the most sensitive prion tests. One of the latter tests is quaking-induced conversion (QuIC), which can be as sensitive as in vivo bioassays, but much more rapid, higher throughput, and less expensive. Now we have integrated antibody 15B3-based immunoprecipitation with QuIC reactions to increase sensitivity and isolate prions from inhibitors such as those in plasma samples. Coupling of immunoprecipitation and an improved real-time QuIC reaction dramatically enhanced detection of variant Creutzfeldt-Jakob disease (vCJD) brain tissue diluted into human plasma. Dilutions of 1014-fold, containing ~2 attogram (ag) per ml of proteinase K-resistant prion protein, were readily detected, indicating ~10,000-fold greater sensitivity for vCJD brain than has previously been reported. We also discriminated between plasma and serum samples from scrapie-infected and uninfected hamsters, even in early preclinical stages. This combined assay, which we call “enhanced QuIC” (eQuIC), markedly improves prospects for routine detection of low levels of prions in tissues, fluids, or environmental samples

Transient rapamycin treatment can increase lifespan and healthspan in middle-aged mice

The FDA approved drug rapamycin increases lifespan in rodents and delays age-related dysfunction in rodents and humans. Nevertheless, important questions remain regarding the optimal dose, duration, and mechanisms of action in the context of healthy aging. Here we show that 3 months of rapamycin treatment is sufficient to increase life expectancy by up to 60% and improve measures of healthspan in middle-aged mice. This transient treatment is also associated with a remodeling of the microbiome, including dramatically increased prevalence of segmented filamentous bacteria in the small intestine. We also define a dose in female mice that does not extend lifespan, but is associated with a striking shift in cancer prevalence toward aggressive hematopoietic cancers and away from non-hematopoietic malignancies. These data suggest that a short-term rapamycin treatment late in life has persistent effects that can robustly delay aging, influence cancer prevalence, and modulate the microbiome.P30 AG013280 - NIA NIH HHS; T32 AG000057 - NIA NIH HH