Background
The
in vitro
permeation test (IVPT) using
ex
vivo
human skin is a sensitive and robust model system that has been vital in elucidating the fundamental parameters surrounding the absorption ...of both therapeutic agents and industrial chemicals through skin. FDA and OECD IVPT Guidances recommend that each skin section selected for study should be screened prior to use to ensure that the stratum corneum integrity is retained. Three methods are currently considered acceptable: 1) transepidermal water loss (TEWL), 2) electrical resistance, and 3) tritiated water (
3
H
2
O) absorption.
Methods
A retrospective analysis of data from the authors’ laboratory has been performed with the objective of addressing a number of questions regarding the
3
H
2
O and TEWL integrity tests, and the population attributes of a large database consisting of 17,330 individual skin sections obtained from 459 skin donors. The applicability and usefulness of these tests, when compared to companion permeation data obtained from 25 topical drug products, has also been examined.
Results
Both integrity tests found water permeability to be equal in White and Hispanic races but higher than in Blacks,
3
H
2
O being more discriminating than TEWL. Male skin is more permeable than female and there is a slight decrease in permeability with advancing age in both groups. Correlation between
3
H
2
O absorption and drug absorption revealed a minimal relationship between the two in most cases, the Pearson correlation coefficient ranging from -0.417 to 0.953. Additionally, drug outliers were not always identified with a failing integrity test.
Conclusion
The results call for a critical reexamination of the value of the
3
H
2
O integrity test, and by extension, TEWL, for use in IVPT studies.
Abstract Heart valve tissue engineering based on decellularized xenogenic or allogenic starter matrices has shown promising first clinical results. However, the availability of healthy homologous ...donor valves is limited and xenogenic materials are associated with infectious and immunologic risks. To address such limitations, biodegradable synthetic materials have been successfully used for the creation of living autologous tissue-engineered heart valves (TEHVs) in vitro. Since these classical tissue engineering technologies necessitate substantial infrastructure and logistics, we recently introduced decellularized TEHVs (dTEHVs), based on biodegradable synthetic materials and vascular-derived cells, and successfully created a potential off-the-shelf starter matrix for guided tissue regeneration. Here, we investigate the host repopulation capacity of such dTEHVs in a non-human primate model with up to 8 weeks follow-up. After minimally invasive delivery into the orthotopic pulmonary position, dTEHVs revealed mobile and thin leaflets after 8 weeks of follow-up. Furthermore, mild-moderate valvular insufficiency and relative leaflet shortening were detected. However, in comparison to the decellularized human native heart valve control – representing currently used homografts – dTEHVs showed remarkable rapid cellular repopulation. Given this substantial in situ remodeling capacity, these results suggest that human cell-derived bioengineered decellularized materials represent a promising and clinically relevant starter matrix for heart valve tissue engineering. These biomaterials may ultimately overcome the limitations of currently used valve replacements by providing homologous, non-immunogenic, off-the-shelf replacement constructs.
Dopaminergic (DA) signaling governs the control of complex behaviors, and its deregulation has been implicated in a wide range of diseases. Here we demonstrate that inactivation of the Fto gene, ...encoding a nucleic acid demethylase, impairs dopamine receptor type 2 (D2R) and type 3 (D3R) (collectively, 'D2-like receptor')-dependent control of neuronal activity and behavioral responses. Conventional and DA neuron-specific Fto knockout mice show attenuated activation of G protein-coupled inwardly-rectifying potassium (GIRK) channel conductance by cocaine and quinpirole. Impaired D2-like receptor-mediated autoinhibition results in attenuated quinpirole-mediated reduction of locomotion and an enhanced sensitivity to the locomotor- and reward-stimulatory actions of cocaine. Analysis of global N(6)-methyladenosine (m(6)A) modification of mRNAs using methylated RNA immunoprecipitation coupled with next-generation sequencing in the midbrain and striatum of Fto-deficient mice revealed increased adenosine methylation in a subset of mRNAs important for neuronal signaling, including many in the DA signaling pathway. Several proteins encoded by these mRNAs had altered expression levels. Collectively, FTO regulates the demethylation of specific mRNAs in vivo, and this activity relates to the control of DA transmission.
The diglossia in German-speaking Switzerland affects many aspects of language use of the speakers of this area, among them the question of how to render toponyms in writing. In the 19th century, ...toponyms were generally transposed from spoken Swiss German to Standard German. In this article, we discuss the main strategies of this transposition in the two main sources of toponomastic data for the canton of Bern in the 19th century, i. e. the gazetteer by Durheim and the so-called Siegfriedkarte (the predecessor of the modern official map, the Landeskarte). We also discuss some errors made by their authors when transposing the names, e. g. by mistakenly reverting certain dialectal changes (hypercorrection) or by semantic reanalysis. In the middle of the 20th century, a new regulation issued by the Swiss authorities mandated that toponyms should generally be spelled in accordance to how they are spoken by the local population. This new regulation was implemented for local names, i. e. names of fields, forests, rivers, small settlements etc., but not for names of larger settlements, well-known mountains, rivers or regions, resulting in some inconsistencies which persist on the official maps until today. An initiative implemented by some cantons in the early 21st century to render spoken dialect features more accurately in the spelling of toponyms had to be abandoned because of the resistance of the local population. Until today, and likely also in the future, the spellings of toponyms of German-speaking Switzerland vacillate between adherence to the orthography and sound patterns of (Swiss) Standard German, on the one hand side, and an accurate representation of spoken Swiss German dialect forms, on the other.
Piwi proteins and their associated Piwi-interacting RNAs (piRNAs) are implicated in transposon silencing in the mouse germ line. There is currently little information on additional proteins in the ...murine Piwi complex and how they might regulate the entry of transcripts that accumulate as piRNAs in the Piwi ribonucleoprotein (piRNP). We isolated Mili-containing complexes from adult mouse testes and identified Tudor domain-containing protein-1 (Tdrd1) as a factor specifically associated with the Mili piRNP throughout spermatogenesis. Complex formation is promoted by the recognition of symmetrically dimethylated arginines at the N terminus of Mili by the tudor domains of Tdrd1. Similar to a Mili mutant, mice lacking Tdrd1 show derepression of L1 transposons accompanied by a loss of DNA methylation at their regulatory elements and delocalization of Miwi2 from the nucleus to the cytoplasm. Finally, we show that Mili piRNPs devoid of Tdrd1 accept the entry of abundant cellular transcripts into the piRNA pathway and accumulate piRNAs with a profile that is drastically different from that of the wild type. Our data suggest that Tdrd1 ensures the entry of correct transcripts into the normal piRNA pool.
The pharmacokinetic approach has accelerated the development of high-quality generic medicines with extraordinary cost savings, transforming the pharmaceutical industry and healthcare system in the ...USA. While this is true for systemically absorbed drug products, the availability of generic versions of topical dermatological products remains constrained due to the limited methods accepted for bioequivalence evaluation of these products. The current review explores the possibility of developing appropriate bioequivalence approaches based on pharmacokinetic principles for topical dermatological products. This review focuses on the strengths and limitations of the three most promising pharmacokinetics-based methods to evaluate the performance and bioequivalence of topical dermatological products, which include in vivo skin stripping, in vivo microdialysis, and in vitro permeation testing (IVPT) with excised human skin. It is hoped that recent advances in pharmaceutical and regulatory science will facilitate the development of robust bioequivalence approaches for these dosage forms, enable more efficient methodologies to compare the performance of new drug products in certain pre-approval or post-approval change situations, and promote the availability of high-quality generic versions of topical dermatological products.
The skeletal muscle is a metabolically active tissue that secretes various proteins. These so-called myokines have been proposed to affect muscle physiology and to exert systemic effects on other ...tissues and organs. Yet, changes in the secretory profile may participate in the pathophysiology of metabolic diseases. The present study aimed at characterizing the secretome of differentiated primary human skeletal muscle cells (hSkMC) derived from healthy, adult donors combining three different mass spectrometry based non-targeted approaches as well as one antibody based method. This led to the identification of 548 non-redundant proteins in conditioned media from hSkmc. For 501 proteins, significant mRNA expression could be demonstrated. Applying stringent consecutive filtering using SignalP, SecretomeP and ER_retention signal databases, 305 proteins were assigned as potential myokines of which 12 proteins containing a secretory signal peptide were not previously described. This comprehensive profiling study of the human skeletal muscle secretome expands our knowledge of the composition of the human myokinome and may contribute to our understanding of the role of myokines in multiple biological processes. This article is part of a Special Issue entitled: Biomarkers: A Proteomic Challenge.
•Proteomic profiling identified 548 proteins in CM of hSkMC.•Applying computational filtering assigned 305 proteins as potentially secretory.•Combined proteomic profiling identified 12 novel myokines.
Este trabajo propone adoptar la distinción entre esclarecimiento probatorio y esclarecimiento preparatorio en la reflexión comparada sobre el proceso civil. Se trata de una distinción funcional de ...normas procesales dirigidas al esclarecimiento de los hechos. Permite identificar normas dirigidas a formar la decisión fáctica del juzgador (esclarecimiento probatorio) y distinguirlas de normas dirigidas a proporcionar a las partes el conocimiento suficiente para comprender la fuerza de sus posiciones y tomar decisiones informadas antes de avanzar a la etapa probatoria (esclarecimiento preparatorio). Se demostrará que la confusión de estas categorías podría llevar una comprensión defectuosa del esclarecimiento preliminar del pre-trial anglosajón. A modo de ilustración, se mostrará que la Rule 102 de las Reglas Europeas de Proceso Civil ofrece un ejemplo de cómo conservar los beneficios del intercambio de información del pre-trial de una forma compatible con la estructura procesal continental.
Hypotrichosis simplex is a group of nonsyndromic human alopecias. We mapped an autosomal recessive form of this disorder to chromosome 13q14.11-13q21.33, and identified homozygous truncating ...mutations in P2RY5, which encodes an orphan G protein-coupled receptor. Furthermore, we identified oleoyl-L-alpha-lysophosphatidic acid (LPA), a bioactive lipid, as a ligand for P2Y5 in reporter gene and radioligand binding experiments. Homology and studies of signaling transduction pathways suggest that P2Y5 is a member of a subgroup of LPA receptors, which also includes LPA4 and LPA5. Our study is the first to implicate a G protein-coupled receptor as essential for and specific to the maintenance of human hair growth. This finding may provide opportunities for new therapeutic approaches to the treatment of hair loss in humans.
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