These findings indicate that the HCEC contains precursor cells with a propensity to differentiate into HCECs and that these cells can also produce neuronal and mesenchymal cell proteins.

The exclusion of freeriders from common privileges or public acceptance is widely found in the real world. Current models on the evolution of cooperation with incentives mostly assume peer sanctioning, whereby a punisher imposes penalties on freeriders at a cost to itself. It is well known that such costly punishment has two substantial difficulties. First, a rare punishing cooperator barely subverts the asocial society of freeriders, and second, natural selection often eliminates punishing cooperators in the presence of non-punishing cooperators (namely, ‘second-order’ freeriders). We present a game-theoretical model of social exclusion in which a punishing cooperator can exclude freeriders from benefit sharing. We show that such social exclusion can overcome the above-mentioned difficulties even if it is costly and stochastic. The results do not require a genetic relationship, repeated interaction, reputation or group selection. Instead, only a limited number of freeriders are required to prevent the second-order freeriders from eroding the social immune system.

Indirect reciprocity is one of the key mechanisms for the evolution of cooperation. It relies on mutual monitoring and assessments, i.e., individuals collect information about the past behavior of others and judge whether that behavior is "good" or "bad." A player will not be helped if labeled with a bad image. There are many ways for assessing others, each of which can be interpreted as an elementary form of a moral sense (i.e., a view on what is good or bad). The information can be either public or private: private information can lead to mismatches between the opinions of individuals even when they share the same moral sense. In this paper, the effect of private information on the best-known assessment rules is investigated. In order to calculate payoffs, the concept of an image matrix is introduced. It describes who is good in the eyes of whom, and its time evolution is given by a probabilistic Boolean automaton. In contrast to the public information case, private information leads to the collapse of the sterner assessment rule. Alternatively, stable polymorphisms may subsist, with the milder rule and a more simple-minded rule coexisting together with unconditional cooperators; thus, cooperation can be sustained by indirect reciprocity even in the absence of public information.

ICG showed an inherent toxicity to RGCs in a dose-dependent manner. Lower concentration and shorter staining time of ICG should be used for dye-assisted vitrectomy.

Previous studies from our laboratory showed that human amnion epithelial cells (AECs) have multiple functions, such as synthesis and release of catecholamines, acetylcholine, neurotrophic factors, activin, and noggin. In this study, we investigated the identity of neural progenitor cells in human amnion mesenchyme cells (AMCs), which lie immediately adjacent to the AECs. Cryostat sections revealed that vimentin expression was detected in the AMCs and CK19 in AECs. Vimentin-positive cells made up 97.5% of total cells tested in cultured AMCs. Interestingly, 3.6% of total AMCs expressed the phenotype CK19+/vimentin+, indicating coexpression of epithelial and mesenchyme cell markers. In culturing with bromodeoxyuridine (BrdU) for 24 hr, 66-82% of cells were found to be BrdU positive, suggesting that they have proliferating potency. By using RT-PCR, AMCs express mRNA of nestin and Musashi1. With a neural cell differentiating protocol, cell bodies extended long bipolar or complex multipolar processes. Nestin (87.7% of total cells tested) and Musashi1 (93.1%) were expressed in undifferentiated cells, and their positively stained cells increased in number slightly after induction. Undifferentiated cells were stained by anti-Tuj1 and NF-M, and their positively stained cells increased significantly in number after induction, to 72.8% and 46.0%, respectively. Meanwhile, glial fibrillary acidic protein-positive cells increased from 25.4% to 43.2% after induction. These studies demonstrate that AMCs have phenotypes of neuroglial progenitor cells and can be differentiated into neuroglial phenotypes by optimal differentiation protocol. Eventually, AMC-derived stem cells may be a favorable cell vehicle in regenerative medicine.

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Indirect reciprocity is one of the basic mechanisms to sustain mutual cooperation.Beneficial acts are returned, not by the recipient, but by third parties. Indirect reciprocity is based on reputation and status: it pays to provide help because this makes one more likely to receive help in turn. The mechanism depends on knowing the past behavior of other players, and assessing that behavior. There are many different systems of assessing other individuals, which can be interpreted as rudimentary moral systems (i.e. views on what is 'good' or 'bad'). In this paper, we describe the competition of some of the leading assessment rules called SUGDEN and KANDORI by analytic methods. We show that the sterner rule KANDORI has a slight advantage in the sense that KANDORI-players have more chance to earn higher payoff than SUGDEN-players in the presence of unconditional altruists. On the other hand, we see that the unconditional altruists are eliminated in the long run and that stable polymorphisms of KANDORI and SUGDEN can subsist, but that a moral consensus is realized even in those polymorphic states: all players' images are the same in each observer's eyes.

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