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Comparative Anatomy, Physiology, and Biochemistry of Mammalian Skin
Published in David W. Hobson, Dermal and Ocular Toxicology, 2020
The fine structure of mast cells has been adequately described by Breathnach.38 The nucleus is round and usually lies centrally within the cell (Figure 14). The mast cell has an irregular outline possessing numerous villous folds projecting from the plasmalemma. Common organelles present include mitochondria, a well-developed Golgi apparatus, and smooth and rough endoplasmic reticulum. In addition to the villous processes, another characteristic feature of the mast cell is the presence of a large number of cytoplasmic granules (Figure 14). Each granule is approximately 0.2 to 0.8 μm in diameter and is surrounded by a unit membrane. In humans the granules present a variety of appearances. Granules may have an internal structure which possess a crystalline arrangement, may have a central dense core in a homogeneous background, or may appear translucent. Some granules may contain lamellar bodies. The internal structure of the lamella may also assume different appearances. Some vacuoles may be noted within the mast cell and are thought to be present after a discharge or release of granules.38,212–214 It is thought that the granules are derived from smooth endoplasmic reticulum.215,216
The Role of Biological Lipids in Skin Conditioning
Published in Randy Schueller, Perry Romanowski, Conditioning Agents for Hair and Skin, 2020
Since its earliest descriptions (reviewed in Ref. 7), hypotheses have abounded about the function of the epidermal lamellar body. These ellipsoidal organelles, measuring about 'A X '/a appear initially in the first supra basal cell layer, the stratum spinosum, and continue to accumulate in the stratum granulosum, accounting for about 10% of the volume of the granular cell cytosol. In the outer granular layer, lamellar bodies move to the lateral and apical surfaces, where they are poised to undergo rapid exocytosis (8,9). The lamellar body contains parallel membrane stacks enclosed by a limiting trilaminar membrane. Whereas each lamella appears to be a "disk" in cross sections, with a major electron-dense band separated by electron-lucent material divided centrally by a minor electron-dense band, recent studies have shown instead that lamellar body contents comprise a single membrane structure folded in an accordion-like fashion.
Developmental Aspects of the Alveolar Epithelium and the Pulmonary Surfactant System
Published in Jacques R. Bourbon, Pulmonary Surfactant: Biochemical, Functional, Regulatory, and Clinical Concepts, 2019
Jacques R. Bourbon, Caroline Fraslon
When determining phospholipids in whole tissue, the relative increase may appear modest. In the rabbit, for instance, the increase of total phospholipids is about 50% and that of PC and DSPC is about 100 and 300%, respectively, between day 27 of gestation and the second postnatal day (term = 31 d).105 In the rat, the increase is 65 and 100% for PC and DSPC, respectively, between day 19 and term (22 d).106 The rate of augmentation appears much more dramatic if phospholipids of lung lavage fluid or surfactant material isolated from the lung are considered. In the rabbit, there is a 10-fold increase in the amount of PC and DSPC recovered by lung lavage during the final 4 d of gestation, and there is a further 10- to 15-fold increase in the first day after birth.105,111 In the rat, the isolation of surfactant material from lung lavage fluid or from lung tissue112,113 has similarly evidenced a striking surge of surfactant phospholipids. Total phospholipids and PC in the sole surfactant compartment increase 12.5- and 20-fold, respectively, between gestational-stage d 19.5 and 1 d postpartum113 (Figure 2). PC accounts for 65% of total phospholipids on day 20 and 81% at term.112 Similar increases have been reported for lamellar bodies isolated from rabbit lung.114
Donor related corneal graft infection: a review of literature and preventive strategies
Published in Seminars in Ophthalmology, 2023
In general, it is a common practice for donor corneal tissues to undergo multiple warming cycles before getting an acceptable image of specular count.15 These increased exposure to warm temperatures can be a potential source of contamination. Endothelial keratoplasty warrants frequent exposure to warm temperatures as tissue needs to undergo processing for evaluation and preparation.12 Furthermore, interface created in the prepared tissues for lamellar surgeries can act as a potential shelter for micro-organisms as this area is protected from direct exposure to flushing or reach of antibiotics.16 Risk factors, such as long term hospitalization before death, can attribute in changing the microbial flora of the ocular surface and increase the risk of donor corneal tissue contamination and post-keratoplasty infection such as multi-drug resistant organisms which are nosocomial.17,18 A study from Brazil found increased contamination in donors who had an ICU stay of more than 4 days and in those where the collection to processing time was more than 7.4 hours.19
Lower eyelid entropion in thyroid eye disease
Published in Orbit, 2022
Varshitha Hemanth Vasanthapuram, Milind N. Naik
UBM was performed in four eyes of two patients with bilateral medial entropion. Three distinct lamellae were appreciated in the lower lid as described previously in the literature.13 The middle lamella represents the tarsal plate superiorly and capsulopalpebral fascia (CPF) inferiorly.13 Thickening of this CPF layer was noted (Figure 3). The average thickness of the CPF along the medial limbal plane(MLP), mid-pupillary plane (MPP) and lateral limbal plane (LLP) were 0.86 mm (0.54–1.3 mm), 0.97 mm (0.65–1.27 mm) and 1.11 mm (0.61–1.61 mm) respectively. These measurements were higher in comparison to the CPF thickness in normal adults (0.42 mm) published previously.13 The statistical significance could not be determined owing to the small sample size of four eyelids. The CPF was hypoechoic with a few hyperechoic to diffuse hyperechoic spots within different planes.
The effect of opine on matrix metalloproteinase expression in mice with breast cancer
Published in Archives of Physiology and Biochemistry, 2022
Abdolrasoul Hakimelahi, Rasoul Sharifi, Minoo Mahmoodi, Seyed Mehrdad Kassaee
This method is another way to support gene expression data. First, biopsy samples surrounded by paraffin were cut using microtome in 5 μm thickness. After paraffin removal, the lamellae were washed using xylene and put in various concentration of ethanol. Then, all lamellae were put in distilled water and treated with pepsin. Afterward, primary antibodies of each MMP were added to lamella and incubated in 1 overnight at 4 °C. After washing three times for 5 min; lamella were treated with secondary antibodies (Sigma-Aldrich Co.LLC-UK) against related proteins for 15 min. DAB was employed for the appearance of the reaction between antigen and antibody. After lamellae were washed in water, Haematoxylin was used for background staining. Finally, lamellae were studied by fluorescence microscopy