Structure and Function of the Body, 8th editionStructure and Function of the Body, 8th edition Thibodeau G and Anthony C PTimes Mirror/ Mosby458pp£12.500-8016-50A7-X

1988 ◽  
Vol 3 (10) ◽  
pp. 38-38
Author(s):  
Richard Pitt
Author(s):  
Albert W. Nyongesaa ◽  
Esther M. Malukib ◽  
Jemimah A. Simbaunib

Khat, Catha edulis, use is rampant in Eastern Africa and Middle East countries with associated reports of reproductive function impairment in the body of the user. Reports on recovery post long-term khat exposure are obscure. The present study investigated evidence of restoration of testicular and epididymal structure and function during withdrawal from cytotoxic damage caused by sub-chronic exposure of khat extract. Twenty-eight male rabbits were divided into 7 groups of 4 rabbits each. Group I (control) was administered normal saline while groups II, III and IV were administered 1.0 g/kg, 10 g/kg and 20 g/kg body weight of khat extract, respectively, via oral gavage on alternate days of the week for 12 weeks. Blood samples from animals were collected for hormonal assays followed by euthanasia using 26.4 mg/kg body weight of Sagatal sodium intramuscularly for testicular and epididymal histology. Group V, VI and VII were administered 1.0 g/kg, 10 g/kg and 20 g/kg body weight of khat extract, respectively, orally on alternate days of the week for 12 weeks followed by 1-month withdrawal period, blood samples collected for hormone assays and animals sacrificed for testicular and epididymal histology. High khat dose, 20 g/kg body weight, at sub-chronic exposure caused degeneration in spermatogenic cells with accompanying decrease in plasma FSH and testosterone. Histological output of Sertoli cells, Leydig cells and epididymal epithelium appeared unaffected in treatment groups. Post withdrawal data showed apparent regeneration of seminiferous epithelium and restoration of plasma FSH and testosterone comparable to control. It appears khat extract preferentially affected germ cell spermatogonia and subsequent daughter cells while stem cell spermatogonia were unaffected and contributed to regeneration of germinal epithelium and endocrine function.


‘Cellular structure and function’ covers the roles, structures, and functions of the main four types of macromolecules of the human body, namely proteins, lipids, carbohydrates, and nucleic acids. For these macromolecules, the roles and types of each class are discussed (for proteins this includes their roles as structural proteins and enzymes and their kinetics; for lipids, the roles and types of lipid found in the body are considered; for carbohydrates, their roles including structural and metabolic are discussed; and the structure of nucleic acids is described). Then follows a description of the organization of the cell, including the plasma membrane and its components, and the intracellular organelles. Cell growth, division, and apoptosis are covered, as are the formation of gametes, and finally the principles of how cellular functions can be modulated by pharmacological agents through receptors and signalling pathways are discussed.


1969 ◽  
Vol 69 (5) ◽  
pp. 1075
Author(s):  
Faustena Blaisdell ◽  
Catherine Parker Anthony

2020 ◽  
Vol 21 (8) ◽  
pp. 2764
Author(s):  
Taremekedzwa Allan Sanyanga ◽  
Özlem Tastan Bishop

Human carbonic anhydrase 8 (CA-VIII) is an acatalytic isoform of the α -CA family. Though the protein cannot hydrate CO2, CA-VIII is essential for calcium (Ca2+) homeostasis within the body, and achieves this by allosterically inhibiting the binding of inositol 1,4,5-triphosphate (IP3) to the IP3 receptor type 1 (ITPR1) protein. However, the mechanism of interaction of CA-VIII to ITPR1 is not well understood. In addition, functional defects to CA-VIII due to non-synonymous single nucleotide polymorphisms (nsSNVs) result in Ca2+ dysregulation and the development of the phenotypes such as cerebellar ataxia, mental retardation and disequilibrium syndrome 3 (CAMRQ3). The pathogenesis of CAMRQ3 is also not well understood. The structure and function of CA-VIII was characterised, and pathogenesis of CAMRQ3 investigated. Structural and functional characterisation of CA-VIII was conducted through SiteMap and CPORT to identify potential binding site residues. The effects of four pathogenic nsSNVs, S100A, S100P, G162R and R237Q, and two benign S100L and E109D variants on CA-VIII structure and function was then investigated using molecular dynamics (MD) simulations, dynamic cross correlation (DCC) and dynamic residue network (DRN) analysis. SiteMap and CPORT analyses identified 38 unique CA-VIII residues that could potentially bind to ITPR1. MD analysis revealed less conformational sampling within the variant proteins and highlighted potential increases to variant protein rigidity. Dynamic cross correlation (DCC) showed that wild-type (WT) protein residue motion is predominately anti-correlated, with variant proteins showing no correlation to greater residue correlation. DRN revealed variant-associated increases to the accessibility of the N-terminal binding site residues, which could have implications for associations with ITPR1, and further highlighted differences to the mechanism of benign and pathogenic variants. SNV presence is associated with a reduction to the usage of Trp37 in all variants, which has implications for CA-VIII stability. The differences to variant mechanisms can be further investigated to understand pathogenesis of CAMRQ3, enhancing precision medicine-related studies into CA-VIII.


Parasitology ◽  
1934 ◽  
Vol 26 (2) ◽  
pp. 176-248 ◽  
Author(s):  
G. S. Graham-Smith

A detailed description of the musculature in the different regions of the alimentary canal of Calliphora erythrocephala is given, and an account of the structure and function of the crop, proventriculus, ducts of the Malpighian tubes, rectal valve and rectal papillae. It has been shown by dissections and experiments that a system of channels exists in the rectal papillae through which the body fluid probably circulates, and it is suggested that the very large cells may have functions resembling those of liver cells.


2007 ◽  
Vol 293 (5) ◽  
pp. H2667-H2679 ◽  
Author(s):  
Charlotte Hwa ◽  
William C. Aird

In 1628, William Harvey provided definitive evidence that blood circulates. The notion that blood travels around the body in a circle raised the important question of how nutrients pass between blood and underlying tissue. Perhaps, Harvey posited, arterial blood pours into the flesh as into a sponge, only then to find its way into the veins. Far from solving this problem, Marcello Malpighi's discovery of the capillaries in 1661 only added to the dilemma: surely, some argued, these entities are little more than channels drilled into tissues around them. As we discuss in this review, it would take over 200 years to arrive at a consensus on the basic structure and function of the capillary wall. A consideration of the history of this period provides interesting insights into not only the central importance of the capillary as a focus of investigation, but also the enormous challenges associated with studying these elusive structures.


2020 ◽  
Vol 6 (1) ◽  
pp. 198-206
Author(s):  
A. Golubchikova ◽  
N. Korobtseva

One of the goals of rehabilitation of children with disabilities (HHS) is to improve their quality of life. For this purpose, various technical means, devices and adaptations which solve a number of problems in life of the child are developed. But there is another aspect that affects the quality of life of such children — is the attitude of people around them. The child is emotionally unstable individual, his psyche is very vulnerable to react to negative emotions. In this case the saying that ‘meet on clothes’ is very applicable. And if the child looks aesthetically pleasing, then others perceive him positively. But in some diseases (physical deviations from the norm) there is no ergonomic and aesthetic clothing. The paper considers the interaction of the systems Society — Textile means of rehabilitation — Child. It is revealed that textile means of rehabilitation, including inclusive clothing have an impact not only on the child’s condition, but also on the emotional state of the society in contact with him, especially his parents. Research on the systematization of information about violations of the structure and function of the body allowed to identify and group the possible causes of violations of the proportions of the child’s body. Some can be compensated by the use of fixing products, others through the use of illusions that contribute to the visual alignment of the proportions of the child. The article formulates the basic principles of designing textile means of rehabilitation and inclusive clothing for children with disabilities, aimed at harmonizing the perception of the external appearance of the child.


2019 ◽  
Vol 4 (33) ◽  
pp. eaau6085 ◽  
Author(s):  
Steven M. Lewis ◽  
Adam Williams ◽  
Stephanie C. Eisenbarth

The spleen is the largest secondary lymphoid organ in the body and, as such, hosts a wide range of immunologic functions alongside its roles in hematopoiesis and red blood cell clearance. The physical organization of the spleen allows it to filter blood of pathogens and abnormal cells and facilitate low-probability interactions between antigen-presenting cells (APCs) and cognate lymphocytes. APCs specific to the spleen regulate the T and B cell response to these antigenic targets in the blood. This review will focus on cell types, cell organization, and immunologic functions specific to the spleen and how these affect initiation of adaptive immunity to systemic blood-borne antigens. Potential differences in structure and function between mouse and human spleen will also be discussed.


MRS Bulletin ◽  
2007 ◽  
Vol 32 (10) ◽  
pp. 770-778 ◽  
Author(s):  
K. Subramanyan ◽  
M. Misra ◽  
S. Mukherjee ◽  
K. P. Ananthapadmanabhan

AbstractThis article gives the foundation for understanding the structure and function of human skin and its layers. Skin is our first line of defense against the penetration of external chemicals and bacteria into the body and of water loss from the body. Skin's visual and tactile properties are very much linked to appearance and beauty. Skin treatments as simple as washing with soap affect the mechanics of skin properties, making it dry and brittle versus smooth and elastic. Likewise, natural aging, hormonal changes, and sun exposure affect the properties of skin. Mild cleansing, moisturizer treatments, and regular use of sunscreens can, however, help skin maintain and even improve its quality, appearance, and functional properties.


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