Cuticular differences of the exoskeleton relative to habitat preferences among three terrestrial isopods

Terrestrial isopods have adapted to land life by diverse morphological, physiological and behavioral changes. Isopod species exhibit a large variety of preferences ranging from moist to dry habitats. Isopod cuticle is an interesting model for studying adaptations to terrestrial life. The cuticle consists of a hierarchically organized material which provides protection and sites for muscle attachment. The present paper aimed to investigate the structure of the cuticle in three isopod species in order to relate some peculiar features to an adaptive process to environmental constraints. Results showed that general thickness of Ligia italica cuticle was quite similar to that observed in Porcellio lamellatus. Nevertheless, this cuticle was half as thick as in Porcellio laevis. Although the positive relationship found between total body lengths and the total thickness of the cuticle, the exocuticle did not show any differences between the three species. However, it is the development of a thicker endocuticle in P. laevis which make its total cuticle thickness more important.     

The cost of growing large: costs of post‐weaning growth on body mass senescence in a wild mammal

Individual body mass often positively correlates with survival and reproductive success, whereas fitness costs of growing large are rarely detected in vertebrates in the wild. Evidence that adult body mass progressively declines with increasing age is accumulating across mammalian populations. Growing fast to a large body can increase the cellular damage accumulated throughout life, leading body growth in early life to be negatively associated with the rate of body mass senescence. Moreover, the onset of mass senescence may strongly depend on both sex‐specific reproductive tactics and environmental conditions. Assessing the timing and the rate of body mass decline with increasing age thus offers an opportunity to look for costs of having grown fast, especially after a poor start during early life, in both sexes and in different environments. Using a unique dataset including 30 years of longitudinal data on age‐specific body mass collected in two roe deer Capreolus capreolus populations subjected to contrasted environmental conditions, we looked for potential costs of high post‐weaning growth rate in terms of steeper rate of body mass senescence. Our analyses of body mass senescence accounted for the potential variation in the onset of senescence and allowed explicit comparisons of this variable between sexes and populations. Higher growth rates late in the growing period (after weaning) were associated with a steeper rate of body mass senescence, regardless of early mass (gained before weaning), but at different extents depending on sex and environmental conditions. Body mass senescence occurred earlier in males than in females, especially in the population facing limiting resources. In the wild, although heavy individuals generally survive better than small ones, the costs of growing large late in the growing period only became apparent late in life through mass senescence.     

Design, synthesis and preliminary biological evaluation of acridine compounds as potential agents for a combined targeted chemo-radionuclide therapy approach to melanoma

Various iodo-acridone and acridine carboxamides have been prepared and evaluated as agents for targeted radionuclide and/or chemotherapy for melanoma, due to their structural similarity to benzamides which are known to possess specific affinity for melanin. Three of these carboxamides selected for their in vitro cytotoxic properties were radioiodinated with [(125)I]NaI at high specific activity. Biodistribution studies carried out in B16F0 murine melanoma tumour-bearing mice highlighted that acridone 8f and acridine 9d, presented high, long-lasting tumour concentrations together with an in vivo kinetic profile favourable to application in targeted radionuclide therapy.     

Long-term persistence of vaccine-derived aluminum hydroxide is associated with chronic cognitive dysfunction

Macrophagic myofasciitis (MMF) is an emerging condition, characterized by specific muscle lesions assessing long-term persistence of aluminum hydroxide within macrophages at the site of previous immunization. Affected patients mainly complain of arthromyalgias, chronic fatigue, and cognitive difficulties. We designed a comprehensive battery of neuropsychological tests to prospectively delineate MMF-associated cognitive dysfunction (MACD). Compared to control patients with arthritis and chronic pain, MMF patients had pronounced and specific cognitive impairment. MACD mainly affected (i) both visual and verbal memory; (ii) executive functions, including attention, working memory, and planning; and (iii) left ear extinction at dichotic listening test. Cognitive deficits did not correlate with pain, fatigue, depression, or disease duration. Pathophysiological mechanisms underlying MACD remain to be determined. In conclusion, long-term persistence of vaccine-derived aluminum hydroxide within the body assessed by MMF is associated with cognitive dysfunction, not solely due to chronic pain, fatigue and depression.     

Cellular IAPs inhibit a cryptic CD95-induced cell death by limiting RIP1 kinase recruitment

A role for cellular inhibitors of apoptosis (IAPs [cIAPs]) in preventing CD95 death has been suspected but not previously explained mechanistically. In this study, we find that the loss of cIAPs leads to a dramatic sensitization to CD95 ligand (CD95L) killing. Surprisingly, this form of cell death can only be blocked by a combination of RIP1 (receptor-interacting protein 1) kinase and caspase inhibitors. Consistently, we detect a large increase in RIP1 levels in the CD95 death-inducing signaling complex (DISC) and in a secondary cytoplasmic complex (complex II) in the presence of IAP antagonists and loss of RIP1-protected cells from CD95L/IAP antagonist–induced death. Cells resistant to CD95L/IAP antagonist treatment could be sensitized by short hairpin RNA–mediated knockdown of cellular FLICE-inhibitory protein (cFLIP). However, only cFLIP_L and not cFLIP_S interfered with RIP1 recruitment to the DISC and complex II and protected cells from death. These results demonstrate a fundamental role for RIP1 in CD95 signaling and provide support for a physiological role of caspase-independent death receptor–mediated cell death.     

“When I Was Circumcised I Was Taught Certain Things”: Risk Compensation and Protective Sexual Behavior among Circumcised Men in Kisumu,Kenya

Background

Male circumcision has been shown to reduce the transmission of HIV from women to men through vaginal sex by approximately 60%. There is concern that men may engage in risk compensation after becoming circumcised, diminishing the benefits of male circumcision.

Methods and Findings

We conducted qualitative interviews with 30 sexually active circumcised men in Kisumu, Kenya from March to November 2008. Most respondents reported no behavior change or increasing protective sexual behaviors including increasing condom use and reducing the number of sexual partners. A minority of men reported engaging in higher risk behaviors either not using condoms or increasing the number of sex partners. Circumcised respondents described being able to perform more rounds of sex, easier condom use, and fewer cuts on the penis during sex.

Conclusions

Results illustrate that information about MC''s protection against HIV has disseminated into the larger community and MC accompanied by counseling and HIV testing can foster positive behavior change and maintain sexual behavior.     

Plasmid vector-linked maturation of natural killer (NK) cells is coupled to antigen-dependent NK cell activation during DNA-based immunization in mice

Plasmid DNA vaccines serve in a wide array of applications ranging from prophylactic vaccines to potential therapeutic tools against infectious diseases and cancer. In this study, we analyzed the mechanisms underlying the activation of natural killer (NK) cells and their potential role in adaptive immunity during DNA-based immunization against hepatitis B virus surface antigen in mice. We observed that the mature Mac-1(+) CD27(-) NK cell subset increased in the liver of mice early after DNA injection, whereas the number of the less mature Mac-1(+) CD27(+) NK cells in the liver and spleen was significantly reduced. This effect was attributed to bacterial sequences present in the plasmid backbone rather than to the encoded antigen and was not observed in immunized MyD88-deficient mice. The activation of NK cells by plasmid-DNA injection was associated with an increase in their effector functions that depended on the expressed antigen. Maturation of NK cells was abrogated in the absence of T cells, suggesting that cross talk exists between NK cells and antigen-specific T cells. Taken together, our data unravel the mechanics of plasmid vector-induced maturation of NK cells and plasmid-encoded antigen-dependent activation of NK cells required for a crucial role of NK cells in DNA vaccine-induced immunogenicity.