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Milia-like idiopathic calcinosis cutis (MICC) and subepidermal calcified nodule (SCN) are described as different entities under the heading of idiopathic calcinosis cutis. Although there are some clinical differences, they share many features. Whereas MICC lesions are located mostly on the extremities and rarely on the face, SCN manifests itself mostly on the face, rarely on the extremities. Milia-like idiopathic calcinosis cutis almost always presents with multiple lesions, whereas SCN shows mainly solitary and rarely multiple lesions. Association with Down syndrome (DS) has been reported in up to two-third of the cases with MICC, but not in SCN. We herein present a 5-months-old girl without DS, manifesting a 2mm solitary, white hard papule surrounded by erythema, located on the finger. Histopathologic findings revealed the presence of dermal calcium deposits. When a solitary papular lesion of idiopathic calcinosis is seen in a child, especially if not associated with DS, it is difficult to differentiate MICC from SCN. We believe that these entities may represent variants of the same pathology and it may be more appropriate to designate a solitary lesion as SCN, regardless of its location.

Abstract Transcriptional control of gene expression is an exquisitely regulated process in both animals and plants. Transcription factors (TFs) and the regulatory networks that drive the expression of TF genes in epidermal and subepidermal cell layers in Arabidopsis are unexplored. Here, we identified 65 TF genes enriched in the epidermal and subepidermal cell layers of the shoot apical meristem (SAM). To determine the cell type specificity in different stages of Arabidopsis development, we made YFP based transcriptional fusion constructs by taking a 3‐kb upstream noncoding region above the translation start site. Here, we report that for ~52% (22/42) TF genes, we detected transcription activity. TF genes derived from epidermis show uniform expression in early embryo development; however, in the late globular stage, their transcription activity is suppressed in the inner cell layers. Expression patterns linked to subepidermal cell layer identity were apparent in the postembryonic development. Potential upstream regulators that could modulate the activity of epidermal and subepidermal cell layer‐enriched TF genes were identified using enhanced yeast‐one‐hybrid (eY1H) assay and validated. This study describes the activation of TF genes in epidermal and subepidermal cell layers in embryonic and postembryonic development of Arabidopsis shoot apex.

Transcriptional control of gene expression is an exquisitely regulated process in both animals and plants. Transcription factors (TFs) and the regulatory networks that drive the expression of TF genes in epidermal and subepidermal cell layers in Arabidopsis are unexplored. Here, we identified 65 TF genes enriched in the epidermal and subepidermal cell layers of the shoot apical meristem (SAM). To determine the cell type specificity in different stages of Arabidopsis development, we made YFP based transcriptional fusion constructs by taking a 3‐kb upstream noncoding region above the translation start site. Here, we report that for ~52% (22/42) TF genes, we detected transcription activity. TF genes derived from epidermis show uniform expression in early embryo development; however, in the late globular stage, their transcription activity is suppressed in the inner cell layers. Expression patterns linked to subepidermal cell layer identity were apparent in the postembryonic development. Potential upstream regulators that could modulate the activity of epidermal and subepidermal cell layer‐enriched TF genes were identified using enhanced yeast‐one‐hybrid (eY1H) assay and validated. This study describes the activation of TF genes in epidermal and subepidermal cell layers in embryonic and postembryonic development of Arabidopsis shoot apex. [ABSTRACT FROM AUTHOR]

Subepidermal autoimmune bullous diseases of the skin and mucosae comprise a large group of chronic diseases, including bullous pemphigoid, pemphigoid gestationis, mucous membrane pemphigoid, linear IgA bullous dermatosis, epidermolysis bullosa acquisita, and anti-p200 pemphigoid. These diseases are characterized by an antibody response toward structural components of the basement membrane zone, resulting in subepidermal blistering. The epidemiological features of these diseases vary substantially in different regions of the world. Observational studies investigating comorbidities and associations among patients with these diseases are inconsistent and sometimes inconclusive. This review provides a brief overview regarding each one of the subepidermal autoimmune bullous diseases. In addition, it summarizes the most recent understanding of the epidemiological features and associations of this group of organ-specific autoimmune diseases. [ABSTRACT FROM AUTHOR]

Autoantibodies in patients with autoimmune bullous skin diseases, such as pemphigus or bullous pemphigoid are of diagnostic value and might play a part in the pathogenic scenario. In this study we present five patients with erythematous plaques, subepidermal blister formation of the skin, and the presence of circulating autoantibodies directed against a so far unrecognized 190 kDa antigen in human keratinocytes. Amino acid sequence analysis identified the protein as IQGAP1, a recently described human Ras GTPase-activating-like protein suspected to act as an effector molecule for Cdc42 and Rac1, members of the Rho small GTPase family and to play a key part in regulating E-cadherin-mediated cell adhesion. The protein is selectively recognized by a monoclonal anti-IQGAP1 antibody on western blots and immunoprecipitates from keratinocyte extracts. Indirect immunofluorescence locates IQGAP1 within individual keratinocytes in a cytoplasmic pattern and along the cell periphery at adhesive sites. Our results demonstrate IQGAP1, a newly described multifunctional protein, to be constitutively expressed in human keratinocytes where it may contribute to the integrity of the epidermal layer. Furthermore, we found autoantibodies reacting with IQGAP1 in patients with bullous skin eruptions most apparently belonging to the spectrum of bullous pemphigoid. [ABSTRACT FROM AUTHOR]

Background Cicatricial pemphigoid (CP) is an autoimmune subepidermal blistering disease where autoantibodies target various components of the dermal–epidermal junction, including the bullous pemphigoid antigen 180 (BP180). Objective We determined the exact specificity of circulating IgG and IgA autoantibodies to BP180 in a large number of CP patients. Methods Twenty-six consecutive CP sera were analysed by Western blotting using a panel of cell-derived and recombinant proteins covering the entire BP180 molecule. Results Circulating autoantibodies were detected in all CP sera. Seven sera reacting with laminin-5 were excluded from further analyses; the remaining 19 sera recognized BP180, including six sera (32%) that showed only IgA reactivity to this protein. With the combined use of the soluble BP180 ectodomain (LAD-1) and recombinant BP180 NC16A, 16 of these 19 CP sera (84%) targeted BP180. IgG reactivity was preferentially found against NC16A, whereas IgA antibodies predominantly recognized LAD-1. Thirty-two per cent of the BP180-reative sera revealed reactivity with the intracellular domain of this protein. Conclusions Our findings demonstrate that autoantibodies in CP target epitopes on both extra- and intracellular domains of BP180 and highlight the importance of testing for both IgG and IgA reactivity in these patients' sera. [ABSTRACT FROM AUTHOR]

Abstract: A subepidermal calcified nodule (SCN) is an uncommon benign lesion, which usually develops in early childhood and is typically solitary. A rare form of this lesion has been reported in the eyelid. We report here a case of a 12-year-old girl with bilateral nodules of the right upper eyelid and a left lower eyelid simulating epidermal cyst. The histopathologic examination of the excised nodule confirmed the diagnosis. To our knowledge, this may be the first bilateral case of eyelid SCN reported in the literature. [ABSTRACT FROM AUTHOR]

The shoot apical meristem (SAM) of higher plants harbors stem cells at their tips. In the SAM, stem cell niches maintain the pluripotent nature of these cell types in the central zone (CZ) and allow them to enter in to differentiation pathways either in the peripheral zone (PZ) or rib meristem (RM). Apart from functional zones, SAM is also subdivided in to distinct cell layers termed as; L1 / epidermal, L2 / subepidermal and L3 / corpus cell layer. Thus, SAM is a complex structure made up of multiple cell types having discrete cell identities. In a recent study, we employed the fluorescent activated cell sorting approach to isolate the cell population of functional zones and cell layers and identified the cell population expressed genes (CPEGs). The Gene Ontology (GO) analysis revealed cellular functions of the identified CPEGs. The cell layers of the SAM are involved in pathogen defense, cell differentiation and photosynthesis. We found many genes in SAM CEPGs that responded to hormone treatment. These observations in the future will help researchers working in the area of shoot apex biology to elucidate the gene regulatory network involved in cell and tissue specialization.