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Since embryonic heart development is a complex process and acquisition of human embryonic specimens is challenging, the mechanism by which the embryonic conduction system develops remains unclear. Herein, we attempt to gain insights into this developmental process through immunohistochemical staining and 3D reconstructions. Expression analysis of T‐box transcription factor 3, cytoskeleton desmin, and nucleoskeleton lamin A protein in human embryos in Carnegie stages 11–20 showed that desmin is preferentially expressed in the myocardium of the central conduction system compared with the peripheral conduction system, and is co‐expressed with T‐box transcription factor 3 in the central conduction system. Further, lamin A was first expressed in the embryonic ventricular trabeculations, where the terminal ramifications of the peripheral conduction system develop, and extended progressively to all parts of the central conduction system. The uncoupled spatiotemporal distribution pattern of lamin A and desmin indicated that the association of cytoskeleton desmin and nucleoskeleton lamin A may be a late event in human embryonic heart development. Compared with model animals, our data provide a direct morphological basis for understanding the arrhythmogenesis caused by mutations in human DES and LMNA genes. [ABSTRACT FROM AUTHOR]

Background: Second heart field cells and neural crest cells have been reported to participate in the morphogenesis of the pharyngeal arch arteries (PAAs); however, how the PAAs grow out and are separated from the aortic sac into left and right sections is unknown. Results: An Isl‐1 positive pharyngeal mesenchyme protrusion in the aortic sac ventrally extends and fuses with the aortic sac wall to form a midsagittal septum that divides the aortic sac. The aortic sac division separates the left and right PAAs to form independent arteries. The midsagittal septum dividing the aortic sac has a different expression pattern from the aortic‐pulmonary (AP) septum in which Isl‐1 positive cells are absent. At 11 days post‐conception (dpc) in a mouse embryo, the Isl‐1 positive mesenchyme protrusion appears as a heart‐shaped structure, in which subpopulations with Isl‐1+ Tbx3+ and Isl‐1+ Nkx2.5+ cells are included. Conclusions: The aortic sac is a dynamic structure that is continuously divided during the migration from the pharyngeal mesenchyme to the pericardial cavity. The separation of the aortic sac is not complete until the AP septum divides the aortic sac into the ascending aorta and pulmonary trunk. Moreover, the midsagittal septum and the AP septum are distinct structures. Key Findings: Isl‐1 positive pharyngeal mesenchyme protrusion.Pharyngeal arch arteries.Aortic sac division. [ABSTRACT FROM AUTHOR]

Summary: The activation of NLRP3, NLRC4 and AIM2 inflammasomes is pivotal for innate immunity against some pathogenic fungi, but their role in the pathogenesis of Malassezia folliculitis (MF) remains unclear. The objective of the study was to determine the expression of 4 canonical inflammasomes (NLRP1, NLRP3, NLRC4 and AIM2) and their priming‐associated molecules (TLR2, TLR4, Dectin‐1, Dectin‐2 and NFκB) in MF lesion. Expression of NLRP1, NLRP3, NLRC4, AIM2, caspase‐1, IL‐1β, TLR2, TLR4, Dectin‐1, Dectin‐2 and NFκB was detected by immunohistochemistry in skin lesion of 23 MF patients and normal skin of 12 healthy subjects. Furthermore, NLRP1, NLRP3, NLRC4, AIM2, caspase‐1 and IL‐1β mRNA was measured by quantitative real‐time PCR (qRT‐PCR) in 12 MF cases and 10 controls. Immunohistochemical analysis revealed that NLRP3, NLRC4, AIM2, Casp‐1, IL‐1β, TLR2, TLR4, Dectin‐1, Dectin‐2 and NFκB expression was up‐regulated in the epidermis and dermal inflammatory cells of MF lesion compared with control skin (P < .01‐.05), but NLRP1 expression was not different between both groups (P > .05). qRT‐PCR showed that levels of NLRP3, Casp‐1 and IL‐1β mRNA were significantly increased (P < .01‐.05), whereas those of NLRP1, NLRC4 and AIM2 mRNA were slightly augmented compared to control skin (P > .05). Our observation suggests that simultaneous activation of NLRP3, NLRC4 and AIM2 inflammasomes may play an important role in the pathogenesis of MF. [ABSTRACT FROM AUTHOR]

Biogenic amines are formed from precursor amino acids, mainly by the microbial decarboxylation. The presence of these compounds plays a vital role in oenology because high amounts of them can lead to health problems. Thus, the origin, detection, and quantity of biogenic amines in wine are extremely important for winemaking. This study, focusing on the articles of latest 5 years, not only reviews the analytical methods used for the determination of biogenic amines but also describes the source of biogenic amines from the perspective of microbiological and oenological factors and summarises the strategies for the degradation of amines. The information presented in this review is important to alert about the inadequate quality of wine products, and efforts from the entire productive chain and the government are required to attain consumer safety. [ABSTRACT FROM AUTHOR]

The second heart field ( SHF), foregut endoderm and sonic hedgehog ( SHH) signaling pathway are all reported to associate with normal morphogenesis and septation of outflow tract ( OFT). However, the morphological relationships of the development of foregut endoderm and expression of SHH signaling pathway members with the development of surrounding SHF and OFT are seldom described. In this study, serial sections of mouse embryos from ED9 to ED13 (midgestation) were stained with a series of marker antibodies for specifically highlighting SHF (Isl-1), endoderm (Foxa2), basement membrane (Laminin), myocardium ( MHC) and smooth muscle ( α- SMA) respectively, or SHH receptors antibodies including patched1 (Ptc1), patched2 (Ptc2) and smoothened, to observe the spatiotemporal relationship between them and their contributions to OFT morphogenesis. Our results demonstrated that the development of an Isl-1 positive field in the splanchnic mesoderm ventral to foregut, a subset of SHF, is closely coupled with pulmonary endoderm or tracheal groove, the Isl-1 positive cells surrounding pulmonary endoderm are distributed in a special cone-shaped pattern and take part in the formation of the lateral walls of the intrapericardial aorta and pulmonary trunk and the transient aortic-pulmonary septum, and Ptc1 and Ptc2 are exclusively expressed in pulmonary endoderm during this Isl-l positive field development, suggesting special roles played in inducing the Isl-l positive field formation by pulmonary endoderm. It is indicated that pulmonary endoderm plays a role in the development and specification of SHF in midgestation, and that pulmonary endoderm-associated Isl-l positive field is involved in patterning the morphogenesis and septation of the intrapericardial arterial trunks. [ABSTRACT FROM AUTHOR]

The second heart field ( SHF) is indicated to contribute to the embryonic heart development. However, less knowledge is available about SHF development of human embryo due to the difficulty of collecting embryos. In this study, serial sections of human embryos from Carnegie stage 10 ( CS10) to CS16 were stained with antibodies against Islet-1 (Isl-1), Nkx2.5, GATA4, myosin heavy chain ( MHC) and α-smooth muscle actin (α- SMA) to observe spatiotemporal distribution of SHF and its contribution to the development of the arterial pole of cardiac tube. Our findings suggest that during CS10 to CS12, SHF of the human embryo is composed of the bilateral pharyngeal mesenchyme, the central mesenchyme of the branchial arch and splanchnic mesoderm of the pericardial cavity dorsal wall. With development, SHF translocates and consists of ventral pharyngeal mesenchyme and dorsal wall of the pericardial cavity. Hence, the SHF of human embryo shows a dynamic spatiotemporal distribution pattern. The formation of the Isl-1 positive condense cell prongs provides an explanation for the saddle structure formation at the distal pole of the outflow tract. In human embryo, the Isl-1 positive cells of SHF may contribute to the formation of myocardial outflow tract ( OFT) and the septum during different development stages. [ABSTRACT FROM AUTHOR]