The neck
Rogan J Corbridge in Essential ENT, 2011
The characteristic bulging neck of the bullfrog is well known. It is due to inflation of an air sac connected to its airway. Many lower animals have similar air sacs. It is thought that a small blind-ending space, called the saccule, found in the human larynx may represent this vestigial structure. Sometimes the saccule can enlarge to produce a laryngocoele, a blind-ending outpouching of the laryngeal mucosa. As they expand, laryngocoeles may remain enclosed within the framework of the larynx, in which case they are known as internal laryngocoeles. Alternatively, they can escape from the larynx, via a potential weak spot in the thyrohyoid membrane where the superior laryngeal neurovascular bundle pierces this layer, in which case they are called external laryngocoele. An external laryngocoele may present as a lump in the neck, usually in association with hoarseness.
Comparative Aspects of Pulmonary Surfactant
Jacques R. Bourbon in Pulmonary Surfactant: Biochemical, Functional, Regulatory, and Clinical Concepts, 2019
The lung of Aves — possibly the most performing gas-exchanging organ in animals in relation to the high metabolic rate of birds and/or the rapid changes in oxygen pressure with changes in altitude during flight — is built on a completely different pattern. Contrary to the blind-ending structure of the mammalian lung, it presents as an open-ending structure inserted between the major conducting airways and the air sacs, which are pouches extending into the thorax and abdomen. This remarkable design allows air renewal in lungs at both inspiration and expiration, allowing air circulation through the lungs, in contrast to the alternate inflow and outflow which occur in the mammalian lung. The airways present three orders of bronchi. The complicated system of primary and secondary bronchi serves as connecting channels to the air sac as well as to the tertiary bronchi (parabronchi) which carry air to the exchanging areas. These are formed of air capillaries whose segmentation achieves the enlargement of surface area required in these highly active species.
Complex Pressure Relief Methods
J G Webster in Prevention of Pressure Sores, 2019
Figure 7.3 shows the Low Air Loss Bed System (lalbs) (Watkins and Watson Ltd, Wareham, Dorset, UK). This is a system where the patient is supported on 21 vapor permeable air sacs of polyurethane-coated nylon, each with a depth of 30 cm. The 21 air sacs are in five groups, each group having its own valve to control the air pressure. The pressure in the groups of sacs can be adjusted when the position of the patient is changed to provide maximal contact with the surface of the body. Variable positions of comfort are obtained by means of simple controls, which enable the contour or attitude of the patient to be adjusted, Temperature-controlled air is supplied by a blower unit. The idea of the lalbs came from a High Air Loss Bed System (halbs) which was developed to treat severe bum injuries. The halbs supported the patient directly on air (Scales et al 1967). The lalbs was developed from the halbs for treating the later stages of burns and other conditions which necessitated prolonged bed rest. The lalbs is claimed to fulfill the requirements of an ideal patient support system as proposed by Scales (1976).
Ameliorative effect of synthesized silver nanoparticles by green route method from Zingiber zerumbet on mycoplasmal pneumonia in experimental mice
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Yong Yang, Wenping Song, Zongbo Chen, Qiubo Li, Li Liu
In histopathological staining of the lungs of the control group of animals showed a normal cellular arrangements and normal micro air sacs or alveoli structures. The examination of histological sections of pneumonia induced group of animals (group II) showed a maximum lymphocytes pulmonary interstitial infiltration and plasmocytes and also bronchus and vasodilation congestion was observed. The administration of synthesized silver nanoparticles from Z. zerumbet tubers exhibits a significant (p < .001) decrease peripheral infiltration of lymphocytes and plasmocytes, as well as decreased inflammation of lung cells, was observed when compared to pneumonia induced group of animals (Figure 10). The AgNPs almost restored the damages induced by pneumonia. The treatment with standard drug Azithromycin demonstrates a significant (p < .001) reduction in cellular damages. This result demonstrates that the synthesized silver nanoparticles from Z. zerumbet tubers expressed the ameliorative effects.
Lung regeneration using amniotic fluid mesenchymal stem cells
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Alireza Azargoon, Babak Negahdari
The lung is derived from the foregut endoderm. A quite number of patterning process cause the gut tube separation and other endodermal organs including pancreas, liver, eventually resulting in the generation of the lung buds and trachea [23,24]. Active reciprocal signalling between nearby mesenchyme and developing multipotent distal tip epithelium are necessary for lung buds stereotypical branching morphogenesis, likewise early differentiation events resulting in different cell lineages. The proximal epithelium was firstly formed from proximal progenitors with the emergence of neuroendocrine, basal, ciliated and secretory cells lining the maturing epithelium (Figure 1 and Table 1) [25]. As branching morphogenesis proceeds, bronchioles ultimately branch into alveoli or millions of terminal air sacs, where gaseous exchange took place after birth. The respiratory epithelium is mainly made of two cells before birth; for gaseous exchange-type-I alveolar epithelial cells, and for secreting surfactants-type-II cells needed to stimulate breathing at birth. Lung maturation accomplishment occurs post-natally. As it matures, the turnover of cell decreases and is very slow in the completely mature adult lung (Table 2).
Recent research advances on simulation modeling of temperature distribution in microwave ablation of lung tumors
Published in Computer Assisted Surgery, 2023
Ju Liu, Hongjian Gao, Jinying Wang, Yuezheng He, Xinyi Lu, Zhigang Cheng, Shuicai Wu
Phairoh et al. [27] and Sanpanich et al. [71] studied the effect of endobronchial airflow on MWA by using a tip-open coaxial antenna and a slot-open coaxial antenna, respectively. They placed a catheter with airflow near the microwave antenna to represent a bronchus. Their results showed that in the absence of bronchi, the distribution of electromagnetic wave energy and the shape of coagulation zone were symmetrically spherical. The existence of airflow in the bronchus would affect the heating mode and the damaged zone would be affected by the thermal conductivity and electrical conductivity of air fluid, which resulted in the asymmetry of coagulation shape in the lung model. This study had some limitations because it used a simple lung model for simulation. Constructing a porous lung structure composed of many alveoli or air sacs and taking into account the rich capillary network around the lung would be the follow-up work.
Related Knowledge Centers
- Appendicular Skeleton
- Elastin
- Epithelium
- Lung Compliance
- Oxygen
- Secretion
- Trachea
- Connective Tissue
- Tidal Volume
- Skeletal Pneumaticity