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Tracheal and Bronchial Developmental Abnormalities, and Inflammatory Diseases including Bronchiectasis, Cystic Fibrosis and Bronchiolitis.
Published in Fred W Wright, Radiology of the Chest and Related Conditions, 2022
(c) Other conditions causing a large trachea. Cystic fibrosis or chronic fibrotic lung disease.In the former the trachea may be abnormally flaccid and irregular in shape, probably caused by years of frequent vigorous coughing. In the latter the enlargement may be partly due to hilar elevation and buckling of the trachea.Ehlers-Danlos syndrome, with poor or absent elastic tissue - see also ps. 10.15 - 10.17.Ankylosing spondylitis - see also ps. 12.29 & 19.90 - 19.91.
An introduction to skin and skin disease
Published in Rashmi Sarkar, Anupam Das, Sumit Sethi, Concise Dermatology, 2021
The tissues of the dermis beneath the epidermis are important in giving mechanical protection to the underlying body parts and in binding together all the superficial structures. It is composed primarily of tough, fibrous collagen and a network of fibres of elastic tissue, as well as the vascular channels and nerve fibres of the skin. The dermis is thinnest in the eyelids and thickest on the back. It contributes to 15–20% of the total body weight. There are about 20 different types of collagen, but the adult dermis is made up mainly of types I and III, whereas type IV is a major constituent of the basal lamina of the dermoepidermal junction. Type V collagen is found in papillary dermis and periadnexal areas. Type VI collagen is present throughout the dermis and interfibrillar spaces. Type VII collagen is present in the anchoring fibrils of the dermoepidermal junction. Between the fibres of collagen is a matrix composed mainly of proteoglycan in which there are scattered fibroblasts that synthesize all the dermal components. Collagen bundles are composed of polypeptide chains arranged in a triple-helix format, in which hydroxyproline forms an important constituent amino acid. The important cells of the dermis are fibroblasts, monocytes, macrophages, dendrocytes, and mast cells.
Aortic Surgery
Published in Theo Kofidis, Minimally Invasive Cardiac Surgery, 2021
Cem Alhan, Sahin Senay, Julian Wong, Andrew MTL Choong
The growth rate of the aneurysms at the descending aorta is generally faster (1.9–3.4 mm/year) than those in the ascending aorta. Dissection, urgent procedure and hypertension were associated with an increased growth rate of descending TAAs in patients with Marfan syndrome after aortic valve and proximal aorta surgery for aortic dissection [2–4]. The decision on the timing of repair of descending aortic aneurysms depends on the type of technique to be used. Thoracic endovascular aneurysm repair (TEVAR) is recommended as the first choice of treatment when compared to open surgery in cases with suitable anatomy. TEVAR should be considered, rather than surgery, when anatomy is suitable. In such cases the intervention should be considered in patients with descending aortic aneurysm with maximal diameter ≥55 mm. If TEVAR is not possible, surgical repair should be considered in patients with descending aortic aneurysm with maximal diameter ≥60 mm. In patients with elastic tissue disorders like Marfan syndrome the choice for repair should be surgery [2,3].
The vascular protective effects of trihoney in hypercholesterolemic atherosclerotic rabbits, a comparative study with atorvastatin
Published in Egyptian Journal of Basic and Applied Sciences, 2022
Hamad Abdulsalam Hamad Alfarisi, Muhammad Bin Ibrahim, Zainab Bubakr Hamad Zubi
Masson’s trichrome staining of aortic sections visualized the collagen contents of all stained sections as blue color, while SMCs were stained red color. Atherosclerotic plaques of the trihoney treated group (HCD+H2) had less collagen and more elastin condensed in the upper part of the atherosclerotic plaque. Sections of the control group that were stained by VGS (Figure 3B) showed clear concentric compacted elastic tissue layers (black in color) in tunica media and continuous internal and external elastic laminae. In this normal group, bundles of collagen and SMCs were sandwiched between the elastin layers in tunica media. No elastic tissue fragmentation was found. In contrast, VGS sections from the high cholesterol diet group (Figure 3B) presented a fragmentation of internal and external elastic laminae as well as the disrupted orientation of elastic layers in tunica media, especially at the thickest points of the plaques. Trihoney treated animals (Figures 3) had concentric compact layers of elastic tissues in tunica media, in addition to well retained continuous internal and external elastic laminae. Trihoney treated group that received a higher dose showed condensed elastic tissues in the subendothelial layer, which was not visualized in other atherogenic groups. Atorvastatin received group had compact layers of medial elastic tissues, in addition to evidence of interrupted internal elastic lamina at the thickest points of the atherosclerotic plaque.
Improvement in linear depressed atrophic scar using 755-nm picosecond alexandrite laser vs. ablative fractional carbon dioxide laser
Published in Journal of Cosmetic and Laser Therapy, 2022
Da Woon Lee, Hyeongrae Ryu, Hwan Jun Choi, Eun Soo Park
Brauer et al. reported the effectiveness of 755-nm picosecond laser against depressed acne scar in a collagen remodeling experiment (11). Fractional non-ablative picosecond laser can induce the regeneration of collagen and soft tissue based on laser-induced optical breakdown (LiOB), and thus the mechanism of subcision was similar to that of a laser, improving depressed scars. Melanocytes in the epidermal region absorb the laser energy concentrated by the micro lens array, resulting in the generation and emission of free electrons, which re-absorb the laser light to regenerate further free electrons. Ionized plasma formation occurs, as a result, which triggers an explosive reaction in the surrounding tissues and the creation of microscopic intradermal cavity lesions in the epidermis and dermis. The contracted collagen fibers are released into the cavity to induce additional collagen synthesis and regeneration of elastic tissue and mucin (12).
Leg ulceration with histological features of pseudoxanthoma elasticum
Published in Baylor University Medical Center Proceedings, 2021
Usman Asad, Sheevam Shah, Palak Parekh
To rule out the possibility of calciphylaxis and further identify the etiology of the ulceration, she underwent a skin and soft tissue wedge biopsy with tissue cultures 2 days after admission. At that time, her parathyroid hormone level was 162 pg/mL (reference range 14–65), phosphorus level was 2.2 mg/dL (reference range 2.4–4.5), and calcium was within normal limits. Tissue cultures revealed a polymicrobial infection. Histology demonstrated ulceration with mixed inflammation, bacterial colonies within the surface crust, and nonspecific reactive vascular changes subjacent to the ulcer bed (Figure 2a, 2b). Foci of dystrophic calcification were noted. Von Kossa stain showed elastic tissue abnormalities with calcification (Figure 2c, 2d). There were no diagnostic features of calciphylaxis. Given the nonspecific changes and the clinical appearance of surrounding induration and stasis-type changes, lipodermatosclerosis and ulceration in the background of venous insufficiency were favored. Although she was on antibiotics, her necrotic wound worsened, with black eschar formation, appearance of a dusky rim around the wound, and wet gangrene of the soft tissue. She underwent successful debridement of the wound and was instructed to follow-up with general surgery.