In this paper, we present investigations of mitochondrial morphologies during aging and differentiation of keratinocytes in human skin in vivo. We performed two studies: The first study explored variations of the mitochondrial network in epidermal keratinocytes of young and old volunteers. The second study extended the results by investigating the role of the mitochondrial network during the epidermal turnover.
In our second study we investigated the changes of mitochondrial morphologies during epidermal differentiation. At the beginning of the epidermal turnover proliferation of keratinocytes occurs in the deepest layer of the epidermis, the stratum basale. During their differentation process keratinocytes migrate to upper layers, i.e. the stratum spinosum and the stratum granulosum, and finally transform into dead corneocytes in the stratum corneum. [21] For an analysis of mitochondrial network states during differentiation, we performed examinations in two layers above the stratum basale: in the stratum spinosum and the stratum granulosum. The stratum spinosum is the layer next to the stratum basale, so that keratinocytes in the stratum spinosum are less differentiated than in the stratum granulosum which is the last living epidermal layer before cornification occurs. We observed that the number of mitochondrial clusters tends to increase during differentiation. Additionally, clusters significantly shrink to smaller volumes and more compact shapes. These parameters indicate that mitochondrial networks in the stratum spinosum establish fused states which fragment during differentiation processes.
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Have the research findings been replicated? If so, have the results only been replicated at the same laboratory? The best way to know an ergogenic aid works is to see that results have been replicated in several studies preferably by several separate, distinct research groups. The most reliable ergogenic aids are those in which multiple studies, conducted at different labs, have reported similar results of safety and efficacy. Additionally, replication of results by different, unaffiliated labs with completely different authors also removes or reduces the potentially confounding element of publication bias (publication of studies showing only positive results) and conflicts of interest. A notable number of studies on ergogenic aids are conducted in collaboration with one or more research scientists or co-authors that have a real or perceived economic interest in the outcome of the study. This could range from being a co-inventor on a patent application that is the subject of the ergogenic aid, being paid or receiving royalties from the creation of a dietary supplement formulation, providing consulting services for the company or having stock options or shares in a company that owns or markets the ergogenic aid described in the study. An increasing number of journals require disclosures by all authors of scientific articles, and including such disclosures in published articles. This is driven by the aim of providing greater transparency and research integrity. It is important to emphasize that disclosure of a conflict of interest does not alone discredit or dilute the merits of a research study. The primary thrust behind public disclosures of potential conflicts of interest is first and foremost transparency to the reader and second to prevent a later revelation of some form of confounding interest that has the potential of discrediting the study in question, the findings of the study, the authors, and even the research center or institution where the study was conducted.
If fetal CMV infection is confirmed, no standard therapy exists for in utero treatment. Available clinical studies support the possible effectiveness and safety of CMV hyperimmune globulin in pregnancy for prevention or treatment of congenital CMV.88,89 A nonrandomized trial of CMV hyperimmune globulin in women not infected with HIV with primary CMV infection in pregnancy found decreased incidence of having a symptomatic newborn at birth90 and regression of fetal cerebral abnormalities;91 however, a well-designed, prospective, randomized, placebo-controlled study with relatively large sample size subsequently found no benefit of CMV hyperimmune globulin in pregnant women.88,92,93 A second randomized clinical trial that planned to enroll 800 patients with primary CMV infection at 2ff7e9595c
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