Characterizing Hyperspectral Microscope Imagery for Classification of Blueberry Firmness with Deep Learning Methods

Firmness is an important quality indicator of blueberries. Firmness loss (or softening) of postharvest blueberries has posed a challenge in its shelf-life quality control and can be delineated with its microstructural changes. To investigate spatial and spectral characteristics of microstructures based on firmness, hyperspectral microscope imaging (HMI) was employed for this study. The mesocarp area with 20× magnification of blueberries was selectively imaged with a Fabry–Perot interferometer HMI system of 400–1000 nm wavelengths, resulting in 281 hypercubes of parenchyma cells in a resolution of 968 × 608 × 300 pixels. After properly processing each hypercube of parenchyma cells in a blueberry, the cell image with different firmness was examined based on parenchyma cell shape, cell wall segment, cell-to-cell adhesion, and size of intercellular spaces. Spectral cell characteristics of firmness were also sought based on the spectral profile of cell walls with different image preprocessing methods. The study found that softer blueberries (1.96–3.92 N) had more irregular cell shapes, lost cell-to-cell adhesion, loosened and round cell wall segments, large intercellular spaces, and cell wall colors that were more red than the firm blueberries (6.86–8.83 N). Even though berry-to-berry (or image-to-image) variations of the characteristics turned out large, the deep learning model with spatial and spectral features of blueberry cells demonstrated the potential for blueberry firmness classification with Matthew’s correlation coefficient of 73.4% and accuracy of 85% for test set.

Comparison of the infection biology of Teratosphaeria destructans and Teratosphaeria epicoccoides on Eucalyptus

Leaf blight caused by Teratosphaeria destructans is one of the most important diseases of Eucalyptus planted in the sub-tropics and tropics. In contrast, the better-known Teratosphaeria epicoccoides, while also a primary pathogen of Eucalyptus, causes less damage to trees in these areas. Although T. destructans is an aggressive pathogen, nothing is known about its infection biology. In this study, the conditions for infection and disease development caused by T. destructans and T. epicoccoides were evaluated and compared on a Eucalyptus grandis x Eucalyptus urophylla hybrid clone. The optimal temperature for the germination of T. destructans ranged from 25 to 30 oC and 15 to 20 oC for T. epicoccoides. The germination of these pathogens was favored under conditions of light and high levels of relative humidity. Penetration by T. destructans and T. epicoccoides occurred via stomata and the hyphae colonized the intercellular spaces of infected leaves. Symptoms were clearly visible three weeks after inoculation by both pathogens and reproductive structures started to develop in substomatal cavities at four weeks after inoculation. The results of this study will facilitate the establishment of rapid screening trials based on artificial inoculations aimed at reducing the impact of disease caused by T. destructans.

Desmoplakin and periplakin genetically and functionally contribute to eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a chronic allergic inflammatory disease with a complex underlying genetic etiology. Herein, we conduct whole-exome sequencing of a multigeneration EoE pedigree (discovery set) and 61 additional multiplex families with EoE (replication set). A series of rare, heterozygous, missense variants are identified in the genes encoding the desmosome-associated proteins DSP and PPL in 21% of the multiplex families. Esophageal biopsies from patients with these variants retain dilated intercellular spaces and decrease DSP and PPL expression even during disease remission. These variants affect barrier integrity, cell motility and RhoGTPase activity in esophageal epithelial cells and have increased susceptibility to calpain-14–mediated degradation. An acquired loss of esophageal DSP and PPL is present in non-familial EoE. Taken together, herein, we uncover a pathogenic role for desmosomal dysfunction in EoE, providing a deeper mechanistic understanding of tissue-specific allergic responses.

Epidermal Hyaluronan in Barrier Alteration-Related Disease

In skin, although the extracellular matrix (ECM) is highly developed in dermis and hypodermis, discrete intercellular spaces between cells of the living epidermal layers are also filled with ECM components. Herein, we review knowledge about structure, localization and role of epidermal hyaluronan (HA), a key ECM molecule. HA is a non-sulfated glycosaminoglycan non-covalently bound to proteins or lipids. Components of the basal lamina maintain some segregation between the epidermis and the underlying dermis, and all epidermal HA is locally synthesized and degraded. Functions of HA in keratinocyte proliferation and differentiation are still controversial. However, through interactions with partners, such as the TSG-6 protein, HA is involved in the formation, organization and stabilization of the epidermal ECM. In addition, epidermal HA is involved in the formation of an efficient epidermal barrier made of cornified keratinocytes. In atopic dermatitis (AD) with profuse alterations of the epidermal barrier, HA is produced in larger amounts by keratinocytes than in normal skin. Epidermal HA inside AD lesional skin is located in enlarged intercellular spaces, likely as the result of disease-related modifications of HA metabolism.

Heterozygous Arrhythmogenic Cardiomyopathy-desmoplakin Mutation Carriers Exhibit a Subclinical Cutaneous Phenotype with Cell Membrane Disruption and Lack of Intercellular Adhesion

Genetic variants that result in truncation in desmoplakin (DSP) are a known cause of arrhythmogenic cardiomyopathy (AC). In homozygous carriers, the combined involvement of skin and heart muscle is well defined, however, this is not the case in heterozygous carriers. The aim of this work is to describe cutaneous findings and analyze the molecular and ultrastructural cutaneous changes in this group of patients. Four women and eight men with a mean age of 48 ± 14 years were included. Eight met definitive criteria for AC, one was borderline and three were silent carriers. No relevant macroscopic changes in skin and hair were detected. However, significantly lower skin temperature (29.56 vs. 30.97 °C, p = 0.036) and higher transepidermal water loss (TEWL) (37.62 vs. 23.95 g m 2 h 1, p = 0.028) were observed compared to sex- and age-matched controls. Histopathology of the skin biopsy showed widening of intercellular spaces and acantholysis of keratinocytes in the spinous layer. Immunohistochemistry showed a strongly reduced expression of DSP in all samples. Trichogram showed regular nodules (thickening) compatible with pseudomonilethrix. Therefore, regardless of cardiac involvement, heterozygous patients with truncation-type variants in DSP have lower skin temperature and higher TEWL, constant microscopic skin involvement with specific patterns and pseudomonilethrix in the trichogram.

Junctional Modulation of Round Window Membrane Enhances Dexamethasone Uptake into the Inner Ear and Recovery after NIHL

Delivery of substances into the inner ear via local routes is increasingly being used in clinical treatment. Studies have focused on methods to increase permeability through the round window membrane (RWM) and enhance drug diffusion into the inner ear. However, the clinical applications of those methods have been unclear and few studies have investigated the efficacy of methods in an inner ear injury model. Here, we employed the medium chain fatty acid caprate, a biologically safe, clinically applicable substance, to modulate tight junctions of the RWM. Intratympanic treatment of sodium caprate (SC) induced transient, but wider, gaps in intercellular spaces of the RWM epithelial layer and enhanced the perilymph and cochlear concentrations/uptake of dexamethasone. Importantly, dexamethasone co–administered with SC led to significantly more rapid recovery from noise–induced hearing loss at 4 and 8 kHz, compared with the dexamethasone-only group. Taken together, our data indicate that junctional modulation of the RWM by SC enhances dexamethasone uptake into the inner ear, thereby hastening the recovery of hearing sensitivity after noise trauma.

Segmentation of the subcuticular fat body in Apis mellifera females with different reproductive potentials

Evolution has created different castes of females in eusocial haplodiploids. The difference between them lies in their functions and vulnerability but above all in their reproductive potentials. Honeybee queens are highly fertile. On the other hand, the workers are facultatively sterile. However, rebel workers, i.e. workers that develop in a queenless colony, reproduce more often than normal workers. As a result, the fat body of these bees, which apart from acting as the energy reserve, is also the site of numerous metabolic processes, had to specialize in different functions perfected over millions of years of eusocial evolution. Assuming that the variety of functions manifests itself in the pleomorphic structure of the fat body cells, we predicted that also different parts of the fat body, e.g. from different segments of the abdomen, contain different sets of cells. Such differences could be expected between queens, rebels and normal workers, i.e. females with dramatically different reproductive potentials. We confirmed all these expectations. Although all bees had the same types of cells, their proportion and segmental character corresponded with the caste reproductive potential and physiological characteristics shaped in the evolutionary process. The females with an increased reproductive potential were characterized by the presence of oenocytes in the third tergite and high concentrations of compounds responsible for energy reserves, like glucose, glycogen and triglycerides. Queens had very large trophocytes, especially in the third tergite. Only in workers did we observe intercellular spaces in all the segments of the fat body, as well as high protein concentrations—especially in the sternite. As expected, the rebels combined many features of the queens and normal workers, what with other findings can help understand the ways that led to the origin of different castes in females of eusocial Hymenoptera.

Chitin Deacetylases are Required for Epichloë festucae Endophytic Cell Wall Remodelling During Establishment of a Mutualistic Symbiotic Interaction with Lolium perenne

Epichloë festucae forms a mutualistic symbiotic association with Lolium perenne. This biotrophic fungus systemically colonizes the intercellular spaces of aerial tissues to form an endophytic hyphal network, and also grows as an epiphyte. However, little is known about the cell wall remodelling mechanisms required to avoid host defence and maintain intercalary growth within the host. Here we use a suite of molecular probes to show that the E. festucae cell wall is remodelled by conversion of chitin to chitosan during infection of L. perenne seedlings as the hyphae switch from free-living to endophytic growth. When hyphae transition from endophytic to epiphytic growth the cell wall is remodelled from predominantly chitosan to chitin. This conversion from chitin to chitosan is catalysed by chitin deacetylase. The genome of E. festucae encodes three putative chitin deacetylases, two of which (cdaA and cdaB) are expressed in planta. Deletion of either of these genes results in disruption of fungal intercalary growth in the intercellular spaces of plants infected with these mutants. These results establish that these two genes are required for maintenance of the mutualistic symbiotic interaction between E. festucae and L. perenne.

Qualitative Anatomical Characteristics of Compression, Lateral, and Opposite Woods in Pinus merkusii and Agathis loranthifolia

This study aimed to observe andcompare the qualitative anatomical characteristics of compression (CW), lateral (LW), and opposite (OW) woodsin the stem wood of Sumatran pine (Pinus merkusii) and Agathis (Agathis loranthifolia). The anatomical characteristics were observed using optical microscopy and scanning electron microscopy. CW showed a gradual transition from earlywood to latewood in both species, circular tracheid shape, many intercellular spaces, irregular tracheid tips, helical cavities, and slit-like bordered pits. CW of Sumatran pine showed an indistinct growth ring, whileCW of Agathis showed a distinct growth ring. Helical ribs occurred only in CW of Sumatran pine. LW and OW showed an oval tracheid with an angular outline, regular tracheid arrangement, and tapered tracheid tips in both species. LW and OW showed mainly uniseriate bordered pits in Sumatran pine, while LW and OW of Agathis frequently showed multiseriatebordered pits. CW, LW, and OW showed fusiform and uniseriate rays in Sumatran pine, while those of Agathis showed uniseriate rays. In conclusion, CW showed distinctive qualitative anatomical characteristics to LW and OW in both species, while LW and OW mainly showed similar characteristics. In particular, there were considerably distinctive characteristics between CW from both species.Keywords: Agathis, anatomical characteristics, reaction wood, Sumatran pine

Formation Mechanism and Anatomical Structure of the Knee Roots of Taxodium Ascendens

Aims: Flooding seriously limits the growth and distribution of plants. Taxodium ascendens is a typical tree species with high flood tolerance, and it can generate knee roots in the wetlands. This study was conducted to understand the formation mechanism of the knee roots.Methods: The number and size of knee roots and soil flooding conditions were investigated in this study. Furthermore, physiology, biochemical responses, and the anatomical structure of knee roots and underground roots were measured at different developmental stages. Results: The results show that the formation of knee roots was significantly affected by the soil water table (P < 0.05). Moreover, knee root formation was affected by ethylene and indole-3-acetic acid (IAA) concentrations in the roots. The 1-aminocyclopropane-1-carboxylic acid (ACC) content and ACC synthase activity were significantly lower in the knee roots than in the underground roots. The ethylene release rate was significantly higher in the knee roots than in the underground roots (P < 0.05), and IAA content first increased and then decreased with knee root development. The cells of the periderm at the apex of the knee roots were dead and had a large number of intercellular spaces, which was beneficial for the growth of T. ascendens. Conclusions: Seasonal flooding induced the production of endogenous hormones, resulting in the formation of knee roots, which improved root respiration and ventilation. The results obtained can gain a basis for the formation mechanism of knee roots and provide scientific evidence for the afforestation and management under wetland conditions.