Keratins in Skin Epidermal Development and Diseases

Epidermal keratinocyte (KC), the major cell type in the skin epidermis, plays critical roles in forming a permeability barrier to separate internal organs from external stimuli. Keratins, constituting about 30–80% of the total protein in KCs, form the major intermediate filament cytoskeleton of KC. Keratins consist of 54 unique genes in humans and they are expressed in cell-, differentiation- and development-dependent manner. While keratin pairs K5-K14 and K1-K10 are normally associated with KCs at different cell differentiation stages, other keratin pairs such as K6-K16/K17 and K8–K18 and are usually not expressed in normal skin interfollicular epidermis, but are elevated during wounding, inflammatory skin diseases such as psoriasis or malignant conversion of KC. The expression and function of keratins are tightly regulated at both transcriptional and post-transcriptional levels. Inherited or spontaneous mutations in keratins or abnormal keratin regulations or modifications can cause KC and cutaneous tissue fragility, skin hypertrophic and inflammatory conditions or malignant transformation of KC, therefore accounting for a large number of disorders in human skin. Here we review the recent literature on how keratins are normally expressed during skin development and how mutations or misregulations of these keratins are involved in the pathogenesis of skin diseases

3-[(Cyclo­hexyl­idene)amino]-1-(4-methyl­phen­yl)thio­urea

In the title compound, C14H19N3S, the cyclo­hexane ring has a chair conformation. The almost planar amino­thio­urea unit (r.m.s. deviation = 0.0062 Å) is aligned at a dihedral angle of 45.23 (8)° with respect to the benzene ring. Inter­molecular N—H⋯N and N—H⋯S hydrogen bonding stabilizes the crystal structure

Ethyl 3-[2-(p-tolyl­carbamothio­yl)hydrazinyl­idene]butano­ate

The title compound, C14H19N3O2S, was obtained from a condensation reaction of N-(p-tol­yl)hydrazinecarbothio­amide and ethyl acetoacetate. The mol­ecule assumes an E configuration; the thio­semicarbazide and ester groups are located on the opposite sides of the C=N bond. The almost planar thio­semicarbazide unit (r.m.s. deviation = 0.0130 Å) is tilted at a dihedral angle of 49.54 (12)° with respect to the benzene ring. Inter­molecular N—H⋯N and N—H⋯S hydrogen bonding stabilizes the crystal structure. The eth­oxy group of the ester unit is disordered over two positions, with a site-occupancy ratio of 0.680 (10):0.320 (10)

3-[(Furan-2-yl­methyl­idene)amino]-1-(4-methyl­phen­yl)thio­urea

There are two independent mol­ecules in the asymmetric unit of the title compound, C13H13N3OS, which was obtained from a condensation reaction of N-(p-tol­yl)hydrazinecarbothio­amide and furfural. The dihedral angles between the mean planes of the tolyl ring and the (furan-2-yl­methyl­ene)hydrazine unit are 39.83 (8) and 48.95 (7)° in the two mol­ecules. The mol­ecules both exhibit an E configuration. In the crystal, inter­molecular N—H⋯N and N—H⋯S hydrogen bonds connect the two independent mol­ecules

1-Benzyl­idene­amino-3-(4-methyl­phen­yl)thio­urea

In the title compound, C15H15N3S, the almost planar 2-benzyl­idenehydrazinecarbothio­amide unit (r.m.s. deviation = 0.0351 Å) is aligned at a dihedral angle of 64.42 (6)° with respect to the plane of the tolyl ring. The mol­ecule exhibits an E configuration for the azomethine linkage. In the crystal, inter­molecular N—H⋯S hydrogen bonds about centers of inversion lead to the formation of dimers

Type1 Interferons Potential Initiating Factors Linking Skin Wounds With Psoriasis Pathogenesis.

Psoriasis is a chronic autoimmune skin disease that can often be triggered upon skin injury, known as Koebner phenomenon. Type 1 interferons (IFNα and IFNβ), key cytokines that activate autoimmunity during viral infection, have been suggested to play an indispensable role in initiating psoriasis during skin injury. Type 1 IFN-inducible gene signature has been identified as one of the major upregulated gene signatures in psoriatic skin. Type 1 IFNs treatments often directly induce or exacerbate psoriasis, whereas blocking type 1 IFNs signaling pathway in animal models effectively inhibits the development of T cell-mediated skin inflammation and psoriasis-like inflammatory diseases. Epidermal keratinocytes (KCs) occupy the outermost position in the skin and are the first responder to skin injury. Skin injury rapidly induces IFNβ from KCs and IFNα from dermal plasmacytoid dendritic cells (pDCs) through distinct mechanisms. Host antimicrobial peptide LL37 potentiates double-stranded RNA (dsRNA) immune pathways in keratinocytes and single-stranded RNA or DNA pathways in pDCs, leading to production of distinct type 1 IFN genes. IFNβ from KC promotes dendritic cell maturation and the subsequent T cell proliferation, contributing to autoimmune activation during skin injury and psoriasis pathogenesis. Accumulating evidences have indicated an important role of this dsRNA immune pathway in psoriasis pathogenesis. Together, this review describes how skin injury induces type 1 IFNs from skin cells and how this may initiate autoimmune cascades that trigger psoriasis. Targeting keratinocytes or type 1 IFNs in combination with T cell therapy may result in more sustainable effect to treat auto-inflammatory skin diseases such as psoriasis

Distribución del fitoplancton y su relación con variables ambientales en Sanya Bay, mar del Sur de la China

Phytoplankton quantification was conducted in Sanya Bay from January 2005 to February 2006. A submersible in situ spectrofluorometer, which permits the differentiation of four algal groups (green algae, diatoms and dinoflagellates, cryptophytes and cyanobacteria) was used. Seasonal variation of total chlorophyll a concentration showed that high value appeared in summer and low concentration occurred in spring. Diatoms and dinoflagellates group was the predominant phytoplankton all year in the Bay. The stable stratification of phytoplankton vertical distribution came into being in July. During the stratification event, the total chlorophyll a concentration of deep layer was much higher than the surface; cyanobacteria and cryptophyta groups decreased and almost disappeared, however, the concentration of green algae and diatoms and dinoflagellates groups increased. In deep layer, the concentration of diatoms and dinoflagellates group increased sharply, which was about eight times more than that in the surface layer. The vertical profiles character of phytoplankton showed that from inshore stations to outer bay the stratification of phytoplankton vertical distribution gradually strengthened. Dissolved inorganic nutrient especially phosphate and inorganic nitrogen and cold-water upwelling were the main regulating factor for phytoplankton distribution.Desde enero 2005 a febrero 2006, en Sanya Bay se llevó a cabo la cuantificación del fitoplancton. Para ello se usó un espectrofotómetro sumergible in situ que permitía la diferenciación de cuatro grupos de algas (algas verdes, diatomeas y dinoflagelados, criptofitas y cianobacterias). La variación estacional de la concentración de clorofila a, mostraba que los valores altos aparecían en verano y los bajos en invierno. Durante todo el año el grupo de fitoplancton predominante era el de dinoflagelados y diatomeas. La estratificación estable de la distribución vertical del fitoplancton aparecía en julio. Durante la estratificación la concentración total de la clorofila a de la capa profunda era más alta que en la superficie; los grupos de crisófitas y cianobacterias decrecían hasta casi desaparecer, sin embargo la concentración de algas verdes y diatomeas se incrementaba. En la capa profunda la concentración del grupo formado por diatomeas y dinoflagelados se incrementaba considerablemente con concentraciones ocho veces más elevadas que en la superficie. El carácter de los perfiles verticales de fitoplancton desde las estaciones costeras hasta fuera de la Bahía aparecía gradualmente más definido. Los nutrientes inorgánicos correspondientes a fósforo y nitrógeno junto con la subida de agua fría eran los factores principales que regulaban la distribución del fitoplancton

Bis(4-amino­benzene­sulfonato-κO)bis­(propane-1,3-diamine-κ2 N,N′)copper(II) dihydrate

In the title compound, [Cu(C3H10N2)2(C6H6NO3S)2]·2H2O, the CuII atom lies on an inversion center and is hexa­coordinated by four N atoms from two 1,3-diamino­propane ligands and two O atoms from two 4-amino­benzene­sulfonate ligands in a trans arrangement, displaying a distorted and axially elongated octa­hedral coordination geometry, with the O atoms at the axial positions. A three-dimensional network is formed in the crystal structure through O—H⋯O, N—H⋯O and N—H⋯N hydrogen bonds

(E)-1-(4-Methyl­phen­yl)-3-[(1-phenyl­ethyl­idene)amino]­thio­urea

In the title compound, C16H17N3S, the amino­thio­urea unit is nearly planar (r.m.s. deviation = 0.0425 Å), and is twisted with respect to the tolyl and phenyl rings by 57.84 (7) and 15.88 (14)°, respectively; the tolyl and phenyl rings are twisted by 65.64 (11)° to each other. Inter­molecular N—H⋯S and weak C—H⋯S hydrogen bonds are present in the crystal structure