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At least 163 records · Page 9Linked to original sources
PubMed2001

[Segmental variants of the inferior vena cava--manifestations with embryological correlation in differentiation from secondary vena cava occlusion].

The vast variability of the overall rare congenital anomalies of the inferior vena cava (IVC) are mostly detected by accident through different imaging modalities. These cannot be classed as pathological findings, and should not be confused with lymphomas and has to differ from secondary collateral venous pathways. Based on 656 CT examinations 10.5% known forms of IVC anomalies were found. According to the embryological development three main groups of IVC variants could be nosologically classified: agenesis of the suprarenal IVC, anomalies of the pars renalis and anomalies of the infrarenal IVC. Additionally three unusual anomaly complexes were found. For the understanding details of the embryology based on a simplified depiction are presented.

Adolescent↗
PubMed1992

Understanding the fundamentals of embryology in assisted reproductive technology.

This paper emphasises the need to understand the fundamentals of embryology in relation to in vitro fertilisation (IVF) and associated assisted reproductive technologies (ART). It introduces the reproductive technologist and others involved in such programmes to the events that occur during early embryogenesis, which have led to recent developments in IVF/ART. It also covers some of the contributions made by IVF/ART in understanding early events of development, particularly during the first week of human life. The reader is referred to some of the widely used embryology texts and audio-visual aids and also to selected reviews and papers published recently that would help toward a better understanding of early development and ART.

Embryonic and Fetal Development↗
PubMed2004

[Studies of soil embryological characteristics of the Salvia miltiorrhiza of Zhongjiang].

OBJECTIVE: To study the characteristics of the SiO2/R2O3 in non-zonal purple soil in the light of the difference between the high yield and low yield of Salvia miltiorrhiza. METHOD: Both the high yield and low yield drugs developed from the same parental material (k1cy) were chosen in the ecology area in Zhongjiang county, Sichuan Province. By using the air-dried drugs as sample, quadrat sampling method was used to calculat the production. Gravimetric method, volumetric method, and colorimetric method and neutralization titration were used to measure the content of adhesive particle colloids element in the soil. And T-test was used for the variable-difference analysis. RESULT: There was a sharp contrast between the production of high yield and low yield drugs (P < 0.001). The characteristic value of the high yield soil embryology was much higher than that of the low yield soil. CONCLUSION: The characteristic value of the purple soil embryology is one of the important factors of the soil adaptability of the drug and its quality. The weathering degree of the soil is closely related to the yield of the drug.

Aluminum↗
PubMed2006

Littre hernia: surgical anatomy, embryology, and technique of repair.

Littre hernia is the protrusion of a Meckel diverticulum through a potential abdominal opening. Alexis de Littre (1700) reported ileal diverticula and attributed them to traction. August Gottlieb Richter (1785) defined them as preformed, and Johann Friedrich Meckel (1809) postulated their embryologic origin. Sir Frederic Treves (1897) distinguished between Littre and Richter hernia (partial enterocele). Embryologically, Meckel diverticulum is the persistent intestinal part of the omphaloenteric duct through which the midgut communicates with the umbilical vesicle until the fifth week. It is found at the antimesenteric border of the ileum, usually located 30 to 90 cm from the ileocecal valve, measuring 3 to 6 cm in length and 2 cm in diameter. Usual sites of Littre hernia are: inguinal (50%), umbilical (20%), and femoral (20%). Meckel diverticulum may be accompanied in the sac by the ileal loop to which it is attached; rarely, it may undergo incarceration or strangulation, necrosis, and perforation. In children, it is mostly found in umbilical hernias, and the diverticulum is more prone to adhere to the sac. Repair of Littre hernia consists of resection of the diverticulum and herniorraphy; in perforated cases, care must be taken to not contaminate the hernia field.

Digestive System Surgical Procedures↗
PubMed2005

Desperately seeking donors: the 'saviour sibling' decision in Quintavalle v Human Fertilisation and Embryology Authority (UK).

The recent House of Lords decision in Quintavalle v Human Fertilisation and Embryology Authority has raised difficult and complex issues regarding the extent to which embryo selection and reproductive technology can be used as a means of rectifying genetic disorders and treating critically ill children. This comment outlines the facts of Quintavalle and explores how the House of Lords approached the legal, ethical and policy issues that arose out of the Human Fertilisation and Embryology Authority's (UK) decision to allow reproductive and embryo technology to be used to produce a 'saviour sibling' whose tissue could be used to save the life of a critically ill child. Particular attention will be given to the implications of the decision in Quintavalle for Australian family and medical law and policy. As part of this focus, the comment explores the current Australian legislative and policy framework regarding the use of genetic and reproductive technology as a mechanism through which to assist critically ill siblings. It is argued that the present Australian framework would appear to impose significant limits on the medical uses of genetic technology and, in this context, would seem to reflect many of the principles that were articulated by the House of Lords in Quintavalle.

Australia↗
PubMed2006

High origin of a superficial ulnar artery arising from the axillary artery: anatomy, embryology, clinical significance and a review of the literature.

The superficial ulnar artery (SUA) is an ulnar artery of high origin that lies superficially in the forearm. Its reported frequency ranges from 0.17% to 2%. During anatomical dissection in our department we observed a unilateral case of SUA in a 75-year-old white male human cadaver. It originated from the right axillary artery at the level of the junction of the two median nerve roots and followed a looping course, crossing over the lateral root of the median nerve and running lateral to it in the upper and middle thirds of the arm, whereas in the inferior third of the arm the SUA crossed over the median nerve and ran medially to it. In the cubital fossa, it passed superficially over the medial side of the ulnar aponeurosis and coursed subcutaneously in the ulnar side of the forearm superficially to the forearm flexor muscles. In the hand the SUA anastomosed with the superficial palmar branch of the radial artery, creating the superficial palmar arch. Additionally, it participated in the development of the deep palmar arch. The axillary artery, after the origin of the SUA, continued as the brachial artery and divided into the radial and common interosseous arteries in the cubital fossa. The normal ulnar artery was absent. No muscular or other arterial variations were observed in this cadaver. The embryological interpretation of this variation is difficult and it may arise as a result of modifications to the normal pattern of capillary vessel maintenance and regression. The existence of a SUA is undoubtedly of interest to the clinician as well as to the anatomist. This report presents a case of unilateral SUA along with a review of the literature, embryological explanation and analysis of its clinical significance.

Aged↗
PubMed1990

Development of the coronary arteries in staged human embryos (the Paris Embryological Collection revisited).

Twenty seven human embryos from stages 15 to 23 (postsomitic period), belonging to the collection of the "UFR Biomédicale des Saints-Pères, Université René Descartes Paris V", were studied. Details of the aorticopulmonary cleavage were analysed specially aortic valve development and origin of the coronary artery. At stage 18 the aortic valve was clearly distinguished (cup-shaped) presenting semilunar valves and aortic sinus (Valsalvae); at this stage the left coronary artery was detected in 66.7 per cent of the cases as an endothelial epicardial invagination. At stage 19, the left and right coronary arteries were detected simultaneously in 100 per cent of the cases. At stage 20, the coronary arteries showed greater structural complexity with a coat of mesenchymal cells. These results agree with previous data from different embryological collections. These findings suggest that the left coronary artery has a tendency to develop earlier than the right. We found no evidence of the coronary origin from the aortic lumen. This work provides additional information about the embryological development of the heart, obtained from the analyses of a French collection of human embryos.

Aortic Valve↗
PubMedDate not supplied

The embryologic basis of tracheobroncho-pulmonary maldevelopment.

An integrated analysis of 15 patients with tracheobronchial abnormalities, bronchogenic cysts and pulmonary sequestration demonstrates that these diverse clinical conditions are expressions of basic embryologic maldevelopment patterns. The clinical conditions described are indicative of differences in degree of the embryologic disorder. In addition to the clinico-pathologic changes affecting the tracheobroncho-pulmonary components of the respiratory system, the importance of aberrant pulmonary arterial blood vessels is described and the diagnostic importance of ancillary investigations is emphasized.

Bronchi↗
PubMed1985

[Ebstein's disease associated with Fallot's tetralogy. Apropos of a familial case, review of the literature, embryologic and genetic implications].

Ebstein anomaly is a rare congenital cardiac malformation, representing 0.3 p. 100 of all congenital heart disease. The authors report a case of a child with Ebstein anomaly associated with tetralogy of Fallot, whose father had an apparently simple Ebstein anomaly. The association of Ebstein-Fallot is extremely rare with only 5 previously reported cases in the literature. The association Ebstein-VSD-pulmonary stenosis is more frequent (13 cases), whilst the association Ebstein-isolated VSD (33 cases) and Ebstein-pulmonary stenosis/atresia (38 cases) are relatively common. Other very varied associations have also been described. Atrial septal defect is practically an integral part of Ebstein anomaly with an ostium secundum or patent foramen ovale in 51 to 80 p. 100 of cases. The possibility of 2 subjects in the same family with Ebstein anomaly is far from negligible. A review of the literature revealed 7 other reported "pairs". A certain number of other cases also demonstrate the association of Ebstein anomaly with another congenital cardiac malformation in the same family, usually a VSD or tetralogy of Fallot. Our familial case raises the question of a possible embryological link between Ebstein anomaly and tetralogy of Fallot. Our experimental embryological studies also suggest the presence of a common denominator between these two conditions.

Adult↗
PubMedDate not supplied

[Odontostomatogenic focal disease; embryologic and clinical causes of autoimmune pathogenesis].

The autoimmune pathogenesis of the focal odontostomatogenous disease is investigated and emphasis is laid on the different keys of interpretation: at embryologic, clinic and immunologic level. A special attention is paid to the primary meaning of structured or non structured lymphoid tissue of oropharynx, on account of embryologic identity with thymus and bursa of Fabricius, differentiating into sectors of ecto-entodermic stratification. The clinical evidence of the bursa-equivalent significance of Waldeyer ring, appears to lie in the ascertainment of the tonsillar atrophy in course of agammaglobulinaemia of Bruton type. The active chronic irritant phlogistic stimulus in a primary structure could excite the normal production of intolerant clones, so as to exceed the normal physiological homeostasis (giving rise to the autoimmune disease), or alter the mosiac self, inducing a production of autoantibodies.

Animals↗
PubMed1982

Embryological changes induced by weak, extremely low frequency electromagnetic fields.

Fertilized chicken eggs were incubated for 48 hours while exposed to extremely low frequency magnetic fields (ELMF) of 10 Hz, 100 Hz and 1000 Hz with intensities of 0.12, 1.2 and 12 micro T. Gross morphological and histological analysis of the exposed embryos revealed the following effects: (1) ELMF of 100 Hz/1.2 micro T had the most consistent and powerful inhibitory effect on embryogenesis. Development of embryos was reduced to the formation of the three primitive layers. Brain vesicles, auditory pit, neural tube, foregut, heart, vessels, and somites were not developed. Glycosaminoglycans were almost absent. (2) The above results demonstrate a window effect because embryos exposed to 100 Hz/1.2 micro T were less developed than embryos exposed at lower and higher intensities and frequencies. (3) Developing organs reacted with different sensitivity to ELMF of specific frequencies and intensities. Somites were not disturbed by exposure to 10 Hz with any of the intensities used. Formation of blood vessels was completely blocked by ELMF of 1000 Hz/12 micro T while traces of other organs were present. (4) The drastic embryological disturbances described were obtained with much lower intensities (1 micro T = 0.01 Gauss) than those used in studies by other investigators. (5) Embryological alterations induced by ELMF may depend on disturbances in the presence and structure of glycosaminoglycans which are essential elements in cellular activities, including cell migration. (6) The use of ELMF of low intensity may be a powerful method to investigate embryogenetic mechanisms and may also be a useful technique for investigation of other biological systems.

Animals↗
PubMed1978

[Congenital malformations of the inferior vena cava. Embryological, anatomical and radiological study (author's transl)].

Congenital malformations of the inferior vena cava are characterized by their diversity which is related to the complexity of the embryological development of this vessel. The authors review the embryogenesis and origin of the different segments of the inferior vena cava and describe the various types of malformation, including the causative embryological abnormality, ther frequency, possible clinical repercussions, and radiological aspects. Phlebocavography is essential for the identification of the various types of abnormality. Five different types of malformation are reported. Three of these are relatively rare (left inferior vena vaca, congenital membrane of the inferior vena cava, absence of the hepatic segment with continuation of the isolated azygos segment).

Adult↗
PubMed1994

Development of hearing. Part II. Embryology.

We humans hear the way we do because of at least three major forces. The first is phylogeny, the evolutionary changes in the auditory system since its beginnings. Another is embryology, the development of the system in each individual. Finally, there is the biologically determined mechanism we are born with and our interaction with the environment in early postnatal life. This series of articles reviews each aspect so that we may have a fuller appreciation of how it is we come to hear the way we do. Part I described the phylogeny of the auditory system. Part II traces the development in prenatal life of the internal, middle, and external ear and the nervous system by days, weeks, and months. Wherever possible, parallels are drawn between phylogenetic and embryologic development. Part III considers the postnatal aspects of auditory development.

Ear, Inner↗
PubMed1994

Anomalies of the branchial apparatus: a case report and review of embryology, anatomy and development.

The majority of congenital anomalies occurring in the neck are related to the development of the branchial apparatus. This area is responsible for the development of multiple structures in the head and neck and thus its anatomy and embryology are complex. Although cysts, sinuses, and fistulas of the branchial region are not common occurrences, they do present in a variety of settings and are generally easily managed if diagnosed early. A fundamental understanding of their anatomy, embryology, and presentation is needed to appropriately diagnose and manage them. These fundamentals are reviewed and a case report is used to illustrate one of the more common presentations.

Branchial Region↗
PubMed1994

The embryology of lower-extremity torsion.

The presence of torsional deformities in the lower extremities of otherwise normal children is based on a variety of developmental processes. With intrauterine maturation, both rotation and external compression of the extremities take place. These forces result in the normal molding and final position of the limbs. Torsion of the extremities is, thus, a normal embryological process. It is imperative for the treating physician to understand these factors in human development to decide which cases are significant deviations from normal torsion. Knowledge of the embryology and natural history of these conditions is a key to appropriate treatment of patients with torsional or angular malalignments.

Bone Diseases, Developmental↗
PubMed1993

Persistent sciatic artery: embryology, pathology, and treatment.

PURPOSE: The purpose of this article is to describe the embryologic development and anomalous persistence of the sciatic artery, pathologic changes that may occur in the persistent sciatic artery, and management of complications related to these pathologic changes. METHODS: Two patients with persistence of the sciatic artery treated in the authors' experience are reported. In addition, the computerized data base of the University of Mississippi Medical Center was searched for patients with other lower extremity arterial aneurysms, and their records were reviewed for possible aneurysm of a persistent sciatic artery. A review of the literature was undertaken to determine the embryologic development of the persistent sciatic artery, the pathologic changes that have been observed in the sciatic artery, clinical findings associated with these pathologic changes, and methods of treatment. RESULTS: Two patients with persistence of the sciatic artery were treated by the authors. No other cases were identified in 43 patients with 66 lower extremity aneurysms treated at our institution. The first patient presented with acute lower extremity ischemia caused by thrombosis of a sciatic artery aneurysm and was treated successfully with intraarterial thrombolytic therapy followed by interposition graft repair. In the second case an incidental unilateral persistent sciatic artery was identified in a patient with bilateral Buerger's disease presenting with digital gangrene of the contralateral extremity in whom below-knee amputation was eventually required. Bilateral tibial artery occlusion was observed on arteriography. Histologic examination of the amputated limb confirmed findings typical of Buerger's disease, and no microemboli were seen. DISCUSSION: The sciatic artery is a continuation of the internal iliac artery and is the primary blood supply to the lower limb bud during early fetal development. The sciatic artery normally involutes during fetal development, but remnants persist as the popliteal and peroneal arteries after the superficial femoral artery develops and establishes continuity with the popliteal artery. Persistence of the sciatic artery as the major blood supply to the lower extremity in adults is a rare vascular anomaly that may be of surgical significance. Failure to appreciate the persistent sciatic artery as the major inflow into the lower extremity may lead to inappropriate bypass of apparent occlusive disease of the superficial femoral artery. The persistent sciatic artery is also frequently aneurysmal, which may cause critical limb ischemia resulting from thrombosis or embolization of aneurysm thrombus. Options for vascular reconstruction include interposition graft replacement and standard femoropopliteal bypass grafting if the common femoral artery is sufficiently developed to provide adequate inflow. As with other peripheral arterial aneurysms resulting in thrombosis and extensive distal arterial embolization and thrombosis, intraarterial thrombolytic therapy may be useful in selected cases before definitive surgical revascularization.

Adult↗
PubMed1995

Virtual embryology: a 3D library reconstructed from human embryo sections and animation of development process.

The volumetric shape of a human embryo and its development is hard to comprehend as they have been viewed as a 2D schemes in a textbook or microscopic sectional image. In this paper, a CAI and research support system for human embryology using multimedia presentation techniques is described. In this system, 3D data is acquired from a series of sliced specimens. Its 3D structure can be viewed interactively by rotating, extracting, and truncating its whole body or organ. Moreover, the development process of embryos can be animated using a morphing technique applied to the specimen in several stages. The system is intended to be used interactively, like a virtual reality system. Hence, the system is called Virtual Embryology.

Computer Simulation↗