Evidence for Perceptual “Trapping” and Adaptation in Multistable Binocular Rivalry

AbstractWhen a different pattern is presented to each eye, the perceived image spontaneously alternates between the two patterns (binocular rivalry); the dynamics of these bistable alternations are known to be stochastic. Examining multistable binocular rivalry (involving four dominant percepts), we demonstrated path dependence and on-line adaptation, which were equivalent whether perceived patterns were formed by single-eye dominance or by mixed-eye dominance. The spontaneous perceptual transitions tended to get trapped within a pair of related global patterns (e.g., opponent shapes and symmetric patterns), and during such trapping, the probability of returning to the repeatedly experienced patterns gradually decreased (postselection pattern adaptation). These results suggest that the structure of global shape coding and its adaptation play a critical role in directing spontaneous alternations of visual awareness in perceptual multistability

A shape-contrast effect for briefly presented stimuli.

When a suprathreshold visual stimulus is flashed for 60-300 ms and masked, though it is no longer visibly degraded, the perceived shape is vulnerable to distortion effects, especially when a 2rid shape is present. Specifically, when preceded by a flashed line, a briefly flashed circle appears to be an ellipse elongated perpendicular to the line. Given an appropriate stimulus onset asynchrony, this distortion isperceived when the 2 stimuli (~4*) are presented as far as 12 " apart but is not due to perception of apparent motion between the 2 stimuli. Additional pairs of shapes defined by taper and overall curvature also revealed similar nonlocal shape distortion effects. The test shapes always appeared tobe more dissimilar to the priming shapes, adistortion termed ashape-contrast effect. Its properties are consistent with the response characteristics of the shape-tuned neurons in the inferotemporal cortex and may reveal the underlying dimensions of early shape ncoding. From the instant astimulus is presented, the visual system accumulates information about the stimulus and begins to generate a subjective impression of its shape and location. For very brief presentations terminated by a mask, stimuli look fuzzy, ill defined, or intertwined with the details of the mask. Several studies have shown that for durations greater than-50 ms, the stimulus begins to have a relatively sharp, crisp appearance and is seen independently of the mask (e.g.

Do PPARγ Ligands Suppress the Growth of Cholangiocarcinoma or the Cholangiohepatitis Induced by the Tumor?

Cholangiocarcinoma is a predominantly fatal cancer, which can be difficult to treat. It has been reported that the administration of pioglitazone temporarily improved not only diabetic control, but also bile duct carcinoma-induced cholangiohepatitis. Pioglitazone is considered to have both direct and indirect mechanisms of action on the tumor-related hepatitis. Several molecules induced by thiazolidinedione, including Smad pathway-related molecules, adipokines, and other lipid metabolism-related proteins, may directly or indirectly suppress tumor development and/or tumor-induced cholangiohepatitis. Although the most frequent and critical side effect of thiazolidinedione is drug-induced hepatitis, it can probably be avoided by careful monitoring of serum hepatic enzyme levels. Thiazolidinedione should be considered for management of tumor-induced hepatitis in the presence of diabetes unless severe side effects occur

A sequencing protocol of some DNA regions in nuclear, chloroplastic and mitochondrial genomes with an individual colony of Thalassiosira nordenskioeldii Cleve (Bacillariophyceae)

From cultured cells of micro algal species of Thalassiosira nordenskioeldii Cleve, total DNA was extracted with a buffer containing a chelating agent, Chelex 100. Each DNA fragment for 18s rDNA, 16s rDNA and coxI in nuclear, chloroplastic and mitochondrial genomes, respectively, were amplified from the DNA extracts by polymerase chain reactions, and their sequences were determined. This protocol for determining DNA sequences, was scaled down for the DNA extracts from small amounts of cells. Finally, DNA sequences in genomes were determined with 10 cells collected by a micromanipulation technique. The quantity of cells corresponded to an individual colony of this species. With this protocol, DNA sequences in various regions in genomes of each individual micro algal species living in natural environments can be determined directly, without isolation of strains and cultures

Distribution of Quinolones, Sulfonamides, Tetracyclines in Aquatic Environment and Antibiotic Resistance in Indochina

Southeast Asia has become the center of rapid industrial development and economic growth. However, this growth has far outpaced investment in public infrastructure, leading to the unregulated release of many pollutants, including wastewater-related contaminants such as antibiotics. Antibiotics are of major concern because they can easily be released into the environment from numerous sources, and can subsequently induce development of antibiotic-resistant bacteria. Recent studies have shown that for some categories of drugs this source-to-environment antibiotic resistance relationship is more complex. This review summarizes current understanding regarding the presence of quinolones, sulfonamides, and tetracyclines in aquatic environments of Indochina and the prevalence of bacteria resistant to them. Several noteworthy findings are discussed: (1) quinolone contamination and the occurrence of quinolone resistance are not correlated; (2) occurrence of the sul sulfonamide resistance gene varies geographically; and (3) microbial diversity might be related to the rate of oxytetracycline resistance

Sinonasal Schwannoma with New Bone Formation Expressing Bone Morphogenic Protein

Schwannoma is a benign tumor that arises from the sheath of myelinated nerve fibers and may occur in any part of the body. Osteogenesis in schwannoma is extremely rare and, to date, new bone formation in sinonasal schwannoma has not yet been reported. Here, we describe the first reported case of sinonasal schwannoma with new bone formation. The tumor was successfully treated by endoscopic sinus surgery, and the patient showed no evidence of recurrence 24 months postoperatively. Immunohistochemically, the tumor expressed bone morphogenic protein 4, indicating a possible role of this protein in the new bone formation in schwannomas