Difference between revisions of "2017 Group Project 2"

From Embryology
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=Developmental abnormalities=
 
=Developmental abnormalities=
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==Duplication anomalies==
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==Fusion anomalies==
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===Horseshoe kidney===
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===Crossed fused renal ectopia===
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===Fused pelvic kidney===
 
z5017644
 
z5017644
 
=Structures & Functions of Kidneys=  
 
=Structures & Functions of Kidneys=  

Revision as of 16:41, 31 August 2017

2017 Student Projects 
Student Projects: 1 Cerebral Cortex | 2 Kidney | 3 Heart | 4 Eye | 5 Lung | 6 Cerebellum
Student Page - here is the sample page I demonstrated with in the first labs.I remind all students that you have your own Group Forum on Moodle for your discussions, it is only accessible by members of your group.
Editing Links: Editing Basics | Images | Tables | Referencing | Journal Searches | Copyright | Font Colours | Virtual Slide Permalink | My Preferences | One Page Wiki Card | Printing | Movies | Language Translation | Student Movies | Using OpenOffice | Internet Browsers | Moodle | Navigation/Contribution | Term Link | Short URLs | 2018 Test Student

Kidney

Introduction

The kidneys are two bean-shaped organs that play an important role in the renal system (also known as the urinary system). In the womb, the placenta is responsible for maintaining balance of water, nutrients, ion levels, etc. however, after birth, this responsibility is given to the kidneys. As such, they are vital for the everyday functions of the human body as they are the unit responsible for the filtration of blood and subsequent reabsorption of water and other nutrients according to what the body needs. The by-product of this process is urine, and it is excreted from the kidneys into the ureters which then deliver the urine to the urinary bladder.

Filtration is carried out in what is called the "nephron". In humans, the number of nephrons in each kidney can range from 200,000 to 2.5 million however the typical kidney usually has approximately 900,000 to 1 million. Nephrons are the functional units of kidneys and are independent of each other. https://www.ncbi.nlm.nih.gov/pubmed/21604189

Kidney development in the embryo is known as nephrogenesis and has three stages: pronephros, mesonephros and metanephros. This process typically begins in week 4 of gestation and ends in week 36. About 1 in 500 babies are born with a kidney problem due to developmental abnormalities. https://www.kidney.org/atoz/content/detectkid Z5017644 (talk) 16:39, 31 August 2017 (AEST)

Current Research Models

Timeline of Kidney Development

Stages in kidney development

Development of the kidney is called nephrogenesis. Here are the three main stages of nephrogenesis which begins in week 4 of gestation and ends in week 36. It must be noted that whilst nephrogenesis does not continue beyond week 36, maturation of the kidney and its functional units does continue. Z5017644 (talk) 16:35, 31 August 2017 (AEST)

1. Pronephros

The earliest nephric stage in humans, and constitutes the mature kidney in most primitive vertebrates. It extends from the 4th to the 14th somites and consists of 6-10 pairs of tubules. These spill into a pair of primary ducts that are formed at the same level, extend caudally, and eventually reach and spill into the cloaca. The pronephros is a vestigial structure that disappears completely by the 4th week of human embryonic life. (z5015446)

2. Mesonephros

Develops by the formation of mesonephric tubules from the intermediate mesoderm, it is the principal excretory organ during early embryonic life (4—8 weeks). It gradually degenerates, although parts of its duct system become associated with the male reproductive organs. (z5015446)

3. Metanephros

Arises caudal to the mesonephros at five weeks of development; it is the permanent and functional kidney in higher vertebrates. It is derived from the intermediate mesoderm. The ureteric bud arises as a diverticulum from the Wollfian duct, close to the entrance to the cloaca and grows towards and inside the metanephric mesenchyme. (z5015446)

(Jia Min, z5178407)

Developmental abnormalities

Duplication anomalies

Fusion anomalies

Horseshoe kidney

Crossed fused renal ectopia

Fused pelvic kidney

z5017644

Structures & Functions of Kidneys

(Jia Min, z5178407)

Diseases associated with Kidneys

(Jia Min, z5178407)

Z5017644 (talk) 16:39, 31 August 2017 (AEST) https://www.ncbi.nlm.nih.gov/pubmed/20388228

Can kidney disease be associated with nephron number?

Nephron development ceases around week 36 of gestation at the end of nephrogenesis, the body can not create new nephrons beyond that point. Due to the wide range of possible nephron numbers (250,000 - 2.5 million), many investigations have arisen to determine whether a lower nephron count predisposes a person to kidney disease later on in life.

https://www.ncbi.nlm.nih.gov/pubmed/16014104

https://www.ncbi.nlm.nih.gov/pubmed/16774009

https://www.ncbi.nlm.nih.gov/pubmed/21604189

https://www.ncbi.nlm.nih.gov/pubmed/19615565

https://www.ncbi.nlm.nih.gov/pubmed/28818273 Z5017644 (talk) 16:39, 31 August 2017 (AEST)


The Cellular Basis of Kidney Development Mammalian kidney development has helped elucidate the general concepts of mesenchymal-epithelial interactions, inductive signaling, epithelial cell polarization, and branching morphogenesis. Through the use of genetically engineered mouse models, the manipulation of Xenopus and chick embryos, and the identification of human renal disease genes, the molecular bases for many of the early events in the developing kidney are becoming increasingly clear. Early patterning of the kidney region depends on interactions between Pax/Eya/Six genes, with essential roles for lim1 and Odd1. Ureteric bud outgrowth and branching morphogenesis are controlled by the Ret/Gdnf pathway, which is subject to positive and negative regulation by a variety of factors. A clear role for Wnt proteins in induction of the kidney mesenchyme is now well established and complements the classic literature nicely. Patterning along the proximal distal axis as the nephron develops is now being investigated and must involve aspects of Notch signaling. The development of a glomerulus requires interactions between epithelial cells and infiltrating endothelial cells to generate a unique basement membrane. The integrity of the glomerular filter depends in large part on the proteins of the nephrin complex, localized to the slit diaphragm. Despite the kidney's architectural complexity, with the advent of genomics and expression arrays, it is becoming one of the best-characterized organ systems in developmental biology.

WT-1 is Required For Early Kidney Development In humans, germline mutations of the WT-1 tumor suppressor gene are associated with both Wilms' tumors and urogenital malformations. To develop a model system for the molecular analysis of urogenital development, we introduced a mutation into the murine WT-1 tumor suppressor gene by gene targeting in embryonic stem cells. The mutation resulted in embryonic lethality in homozygotes, and examination of mutant embryos revealed a failure of kidney and gonad development. Specifically, at day 11 of gestation, the cells of the metanephric blastema underwent apoptosis, the ureteric bud failed to grow out from the Wolffian duct, and the inductive events that lead to formation of the metanephric kidney did not occur. In addition, the mutation caused abnormal development of the mesothelium, heart, and lungs. Our results establish a crucial role for WT-1 in early urogenital development.

Devina Lorenzia - User:Z5015446

Z5015446 (talk) 16:40, 31 August 2017 (AEST)