Sex and type peculiarities of the topography of the anterior abdominal wall in adult persons of various ages]

In men and in "masculine" shape of the abdomen as compared with women and "feminine" shape of the abdomen the following features of the topography of the anterior-lateral abdominal wall were revealed: a narrower white line, wider straight muscles of the abdomen in their medial and upper parts, less square surface of the lateral muscle-free portions. The inguinal region of men and the "musculine" type of the abdomen are characterized by great dimensions of the superficial and profound rings, weaker aponeurosis of the external oblique abdominal muscle in formation of the anterior wall of the inguinal canal. In elderly and senile age there occur dilatation of the white line, the increase of the amount of chinks and apertures in it as well as of the length of aponeuroses. The superficial inguinal ring expands.     

Double-pedicle transverse rectus abdominis myocutaneous flap for unilateral breast and chest-wall reconstruction

Fifteen patients underwent unilateral breast and chest-wall reconstruction by a double-pedicle transverse rectus abdominis myocutaneous flap technique. Criteria for using both pedicles include (1) exceptionally large soft-tissue requirements, (2) prior abdominal operations compromising the vasculature to portions of the anterior abdominal wall, and (3) certain higher-risk patients with suspected microvascular pathology. Double pedicles allowed the transfer of the skin island as one unit or as two independent hemiellipses of tissue. Follow-up time ranges from 4 to 17 months. Complications included partial tissue loss in two patients, one abdominal flap seroma, and one patient with a hernia.     

Relationship between the spike activities of the small and large intestines

Experiments were performed using chronically implanted electrodes on the dog smooth muscle wall of the stomach and of the small and large intestines. Electrical activity of the muscle wall was recorded before and after feeding. When reaching the terminal ileum the active part of the migrating myoelectrical complex (MMC) continuously induced bursts of spike potentials superimposed on the slow waves. This electrical activity spread to the ascending colon. We also showed the existence of a spike activity on the terminal ileum independent of the MMC (appearing during the phase 1) and propagating to the colon. A relationship between the spike activities of the small and large intestines was also present after feeding. Beside the well-known gastro-colic reflex, we observed an increase in the spike activity of the terminal ileum and ascending colon between the 4th-5th hours after feeding. This probably corresponds to the arrival of the first portions of contents, evacuated from the arrival of the first portions of contents, evacuated from the stomach, and of the last portions of small intestinal contents. In conclusion, there is a relationship between the spike activities of the small and large intestines in starving animals and after feeding, and the terminal ileum plays a substantial role in this relationship.     

Waveform generation of the electric organ discharge inGymnotus carapo

Summary The electric organ (EO) ofGymnotus carapo was studied using different neurohistological techniques including conventional electron microscopy. The electric tissue extends along the fish body from the pectoral girdle to the tip of the tail, constituting a single, undivided organ. However, taking into account the number, arrangement, and innervation of the electrocytes, it is possible to divide the EO into three different portions. The more rostral portion is included within the ventral wall of the abdominal cavity. It consists of singly and doubly innervated electrocytes arranged in two rows at each side of the midline. Innervation of this zone is supplied by the first 5–7 segmental nerves and by the anterior electromotor nerves. Segmental nerves terminate on the rostral faces of doubly innervated electrocytes; axons stemming from the anterior electromotor nerves end on the caudal faces of both doubly and singly innervated electrocytes. There is an intermediate body-tail region in which the electrocytes are arranged in four dorsoventral tubes (tubes 1 to 4) on each side of the midline. In this zone, doubly innervated electrocytes (confined within tube 1) coexist together with singly innervated ones, receiving nerve terminals on their caudal faces (tubes 2, 3, and 4). The innervation characteristics appear modified at more distal portions of the tail where the doubly innervated electrocytes of tube 1 are replaced by singly innervated units. The most distal portion of the EO (approximately its terminal 30%) consists of numerous, homogeneously innervated electrocytes with nerve endings distributed exclusively on their caudal faces. Nerve supply to the intermediate and distal regions derives from the posterior electromotor nerves (PENs) which appear as well-defined anatomical entities beyond the level of metamere XXVII. At the bodytail and more distal regions the innervation pattern of the EO is particularly complex. Thin nerve trunks arise from the PENs and project ventrally toward the electrocyte tubes. Before reaching the electric tissue the electromotor axons branch frequently. Our anatomical studies indicate that the EO is heterogeneous, a feature consistent with most recent electrophysiological and biophysical experiments.Abbreviations AEN anterior electromotor nerve - EMN electromotoneurons - EO electric organ - EOD electric organ discharge - LLN lateral line nerve - PEN posterior electromotor nerve     

The copulatory complex of Hemianax ephippiger (Burmeister) (Aeshnidae: Anisoptera)

Like other Anisoptera Hemianax ephippiger (Burmeister) bears two sets of copulatory apparatuses. The first set which is primary in nature is located on the ventral surface of the ninth abdominal segment and consists of the vestigial penis, the gonocoxites, the supra-anal appendages, the infra-anal appendage. The supra-anal appendages are well developed, lanceolate with serrate margin and spinous apices. They are dorso-ventrally flattened and furnished with long hairs and black teeth-like tubercles (T). The secondary copulatory complex is lodged inside the membranous fossa located on the ventral surface of second and third abdominal segments. It consists of anterior lamina, the posterior lamina, the supporting framework, the hamules, the penis sheath, the penis vesicle and the penis. The anterior lamina is deeply cleft at the posterior margin to accommodate the ovipositor of the female during copulation. Both the portions of the supporting framework are well developed. The anterior portion is somewhat rectangular while the posterior portion is nearly U-shaped. The anterior hamules are well developed with truncated and hooked portions, while the posterior hamules are very much reduced. The penis sheath is forcepate with well developed rectangular flap which hangs over the penis. The penis is stout, clearly demarcated into three segments, and bears a prominent groove on the mid-ventral line.     

Contribution of the skin,rectus abdominis and their sheaths to the structural response of the abdominal wall ex vivo

A better understanding of the abdominal wall biomechanics could help designing new treatments for incisional hernia. In the current study, an experimental protocol was developed to evaluate the contributions of the abdominal wall components to the structural response of the anterior part of the abdominal wall. The specimens underwent 3 dissections (removal of (1) skin and subcutaneous fat, (2) anterior rectus sheath, (3) rectus abdominis muscles). After each dissection, they were subjected to air pressure up to 3 kPa. Ultrasound images and associated elastographic maps were collected at 0, 2 and 3 kPa in the intact state and strains on the internal surface were calculated using stereo-correlation in all states. Strains on the rectus abdominis and linea alba were analyzed. After the dissection of the anterior sheath of the rectus abdominis, longitudinal strain was found significantly different on the linea alba (5% at 3 kPa) and on the rectus abdominis area (11% at 3 kPa). The current results highlight the importance of the rectus sheath in the structural response of the anterior part of the abdominal wall ex vivo. Geometrical characteristics such as thicknesses and radii of curvature and mechanical properties (shear modulus of the rectus abdominis, e.g. at 0 pressure the average value is 14 kPa) were provided in order to facilitate future modeling efforts.     

The vascular terminal network device in the anterior stomach wall

The microcirculatory bed of the anterior stomach wall has been studied in man, dog, rabbit, guinea pig and rat, starting from the fact that in the modern gastro-duodenal surgery the various sectors of this stomach part have a special importance. The stomach microvascular network has been rendered manifest by microcorrosion preparations and by intravascular injections with coloured tracers (China Ink-gelatin, silver nitrate, methylene blue). Examinations under biocular magnifying glass and microscope of the histological slides, as well as of the block-transparentized ones in tetraline, have facilitated the microvascular morphometry as well as the calculation of some hemodynamic indices of blood flow evaluation in a limited territory of the anterior stomach wall. The obtained data can be of use when evaluating the microcirculation of the stomach parietal territories in selective vagotomies, anastomoses, plasties, resections and other operations of the stomach.     

A study of the anatomy, histology and ultrastructure of the digestive tract of Orthrias angorae Steindachner, 1897

The anatomy, histology and ultrastructure of the digestive tract of Orthrias angorae (Steindachner, 1897) were investigated using light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The histological structure consists of four layers: mucosa, submucosa, muscularis and serosa. The esophageal mucosa consists of undifferentiated basal epithelial cells, mucous cells and surface epithelial cells. It was observed that the J-shaped stomach had a meshwork of folds in the cardiac region, and longitudinal folds in the fundic and pyloric regions. A single layer of columnar cells, PAS positive only in their apical portions, forms the epithelium. The convoluted tube-shape intestine is lined by simple columnar epithelial cells, which have microvilli at the apical surface. The wall of the esophagus and stomach are thicker than that of the intestine because of the thick muscle layer. There were numerous goblet cells in the intestine. There were numerous gastric glands in the submucosa layer ofthe cardiac stomach, but none were present in the pyloric region of the stomach. There were no pyloric caeca between the stomach and intestine. The enterocytes with microvilli contained rough endoplasmic reticulum, ribosomes and rounded bodies, and the gastric cells contained a well-developed Golgi apparatus.     

Circulatory organs of abdominal appendages in primitive insects (Hexapoda: Archaeognatha, Zygentoma and Ephemeroptera)

The abdominal circulatory organs and the haemolymph supply of the terminal filament and the cerci were investigated in a total of nine species (serial semithin sections, TEM, in vivo observations). In all investigated species, the dorsal vessel features a bidirectional flow. In the 10th abdominal segment, there is an intracardiac valve preventing flow in the anterior direction. The posterior portion of the dorsal vessel differs significantly from the anterior portion in design and wall structure. Pumping actions and frequencies do not correspond with each other in the two portions. Vessels supply haemolymph to the long terminal appendages. The terminal filament vessel is connected to the dorsal vessel, the two cercal vessels originate from a transverse septum at the base of the terminal filament. All taxa show the same flow pattern through the caudal appendages. Ephemeroptera have a unique spherical body at the posterior end of the dorsal vessel functioning as a backflow valve. The results indicate that the plesiomorphic state of the circulatory organs in the abdomen of primitive insects differ distinctly from that of higher insects which serve as bases for generalized schemes common to entomological textbooks.     

Surgical anatomy of the anterior abdominal wall in normal viscera, dolichoviscerosis and visceroptosis

There are three types in position of the abdominal internal organs: visceronorm, dolichoviscerosis and visceroptosis. The anterior abdominal wall also has its own anatomical peculiarities at every type of the internal organs position. Anatomical differences of its structure at visceronorm and dolichoviscerosis in comparison with visceroptosis are characterized as following: the area of aponeurotic formations of the anterior abdominal wall at dolichoviscerosis and visceroptosis increases and that of the muscular-decreases. Umbilical and inguinal rings are essentially dilated in comparison with those at visceronorm. It means that at dolichoviscerosis and visceroptosis there are anatomical prerequisites for development of external hernias in the anterior abdominal wall. A considerable mobility of the intestinal tract loops at dolichoviscerosis and visceroptosis results in certain disturbances of its function and their outlet into hernial sacs.     

Electrophysiological studies of the isolated posterior moiety of the electroplax of the electric eel

Intracellular microelectrodes were used to measure resting and action potentials of electric eel electroplax cells from which the middle portion of the anterior moiety had been removed. External electrode studies of this preparation have been described by Chagas and Esquibel (C. R. Acad. Sc., Paris, 260: 3172 ('65)). In the present studies it was found that the resting and action potentials were almost as large as normal in the intact portion of the preparation, whereas these potentials were greatly reduced in the areas from which the anterior moiety had been removed. The reduction in amplitude was greater the farther the microelectrode was from the intact portion, indicating the possibility of decremental spread from the intact portions. The action potentials measured with external electrodes appeared to be an average of potentials from the various areas of the preparation. In other experiments the entire anterior moiety of the electroplax was removed, leaving only the innervated plasma membrane plus some adhering cytoplasm and extracellular material. Various high K⁺ solutions were used to bathe the inner surface. No action potentials could be elicited from these preparations, but resting potentials as high as 51 mV were observed using external electrodes. The resting potential could be reduced reversibly by carbamylcholine applied to the outer surface. Carbamylcholine applied to the inner surface had no effect.     

Ontogeny of the partial secondary wall of the otoccipital region of the endocranium in prehatching Alligator mississippiensis (Archosauria, Crocodylia)

The ontogeny of the posterior otic and anterior occipital portions of the neural endocranium of prehatching Alligator mississippiensis was investigated by reconstruction from sectioned material. In Stage 6 of this species, in which the endochondral ossification of the otoccipital region of the neural endocranium is only in its very early stage, two bony outgrowths-laminae-are present at the external wall of the posterior portion of the neural endocranium. The anterior lamina arises from the external surface of the basal plate at the level of the posterior margin of the subcapsular process; the posterior lamina arises from the external surface of that portion of the pila occipitalis that forms the posteroventral wall of the metotic fissure. During ontogeny, both laminae lying in the anteroposterior sequence ossify in membrane, fuse together, grow laterodorsally, and fuse with the lateral wall of the lateral semicircular canal and the crista parotica. This lamina forms a new, secondary wall enclosing the posterior section of the otic capsule and contains the large external jugular foramen (or foramen vagi) in its basal portion. The laminae, designated lamina juxtaotica anterior and posterior (lamina juxtaotica when fused together), have not been recorded previously in crocodylians and are absent in all other Recent reptiles. From the functional point of view, the juxtaotic lamina 1) forms the margins of the external jugular foramen, and 2) forms the floor of the posterior section of the Eustachian tube. In birds, the structure called the metotic cartilage, which arises in ontogeny as an independent element, has a similar position as the juxtaotic lamina. However, the two structures differ in their developmental origins and their relation to the Eustachian tube and the ramus hyomandibularis of the facialis nerve. Moreover, there is no external jugular foramen in birds.     

刀鲚幼鱼消化系统的组织形态学结构

采用光镜和扫描电镜观察长江刀鲚(Coilia nasus)幼鱼消化系统组织形态学结构。结果显示,刀鲚体长,口裂大,含有犬齿状的颌齿和尖锥状的腭齿,具有5对鳃弓,鳃耙长度明显大于鳃丝且表面附着不规则绒毛状细齿;胃呈"Y"型,胃与肠连接处具有16～21个指状环形幽门盲囊;肠为直肠,较短,比肠长为0.241±0.080;肝分为两叶,胰为独立的器官。刀鲚口咽腔为复层鳞状上皮,含有腺体、大量椭圆形黏液细胞、少量杯状细胞及味蕾;胃黏膜都为典型的单层柱状上皮,含有较多由上皮凹陷形成的胃小凹和胃腺;幽门盲囊具有20～25个丰富的褶皱,占满大部分幽门盲囊腔,黏膜层具有微绒毛;中肠黏膜上皮最发达,形成的褶皱细长且连接成网状,单层柱状上皮与复层扁平上皮交替分布。观察结果表明,刀鲚消化系统具有典型肉食性鱼类特征。     

A peritoneal mesothelioma in a captive aardwolf (Proteles cristatus)

A 10-year-old male aardwolf (Proteles cristatus) was presented abdominal distention and emaciation for 3 months. Physical examination revealed firm abdominal masses with effusions. Cytologic assessment of the effusion showed uniform round tumor cells with a surface brush border. Necropsy showed white velvety masses covering the peritoneal surface of the liver, gall bladder, stomach, omentum, mesentery, spleen, intestine, abdominal wall and diaphragm. Histologic examination demonstrated papillary projections, lined with cuboidal tumor cells supported by fibrous connective tissue cores, arising from the serosa of visceral organs. Cytoplasmic vacuolation and a surface brush border were evident on some cells under light microscopy. Tumor cells stained positive for both cytokeratin (AE1/AE3) and vimentin. Electron microscopy showed prominent surface microvilli, rough endoplasmic reticulum, mitochondria and desmosomes in tumor cells. This may be the first reported case of peritoneal mesothelioma in a captive wild aardwolf.     

Ventricle and outflow tract of the African lungfish Protopterus dolloi

We report a morphologic study of the heart ventricle and outflow tract of the African lungfish Protopterus dolloi. The ventricle is saccular and appears attached to the anterior pericardial wall by a thick tendon. An incomplete septum divides the ventricle into two chambers. Both the free ventricular wall and the incomplete ventricular septum are entirely trabeculated. Only a thin rim of myocardium separates the trabecular system from the subepicardial space. The outflow tract consists of proximal, middle, and distal portions, separated by two flexures, proximal and distal. The proximal outflow tract portion is endowed with a layer of compact, well-vascularized myocardium. This portion is homologous to the conus arteriosus observed in the heart of most vertebrates. The middle and distal outflow tract portions are arterial-like, thus being homologous to the bulbus arteriosus. However, the separation between the muscular and arterial portions of the outflow tract is not complete in the lungfish. A thin layer of myocardium covers the arterial tissue, and a thin layer of elastic tissue underlies the conus myocardium. Two unequal ridges composed of loose connective tissue, the spiral and bulbar folds, run the length of the outflow tract. They form an incomplete division of the outflow tract, but fuse at the distal end. The two folds are covered by endocardium and contain collagen, elastin, and fibroblast-like cells. They appear to be homologous to the dextro-dorsal and sinistro-ventral ridges observed during the development of the avian and mammalian heart. Two to three rows of vestigial arterial-like valves appear in the dorsal and ventral aspects of the conus. These valves are unlikely to have a functional role. The possible functional significance of the "gubernaculum cordis," the thick tendon extending between the anterior ventricular surface and the pericardium, is discussed.     

Blood supply of the abdomen revisited, with emphasis on the superficial inferior epigastric artery

The key to understanding the blood supply of the anterior hemiabdomen is knowledge of the central superficial inferior epigastric artery system and the peripheral contribution of the epigastric, deep and superficial circumflex, and iliac arteries and external oblique perforators. These systems all feed into the subdermal plexus of the anterior abdominal wall. Angiographic confirmation of multiple communications between the superficial inferior epigastric artery and other major sources of abdominal wall blood supply has been obtained. Experience using the superficial inferior epigastric artery flap as a pedicled and microsurgical transfer has been described.     

Lymphatic bed of layers of the abdominal wall in the human inguinal area]

Lymphatic bed in the layers of the inguinal area was studied in connection with age in 70 human corpses. Polychromic injection of arteries, veins and lymphatic bed, staining of preparations after van Gieson, Weigert, with hematoxylin-eosin and morphometry were the methods applied. It was stated that lymphatic capillaries penetrate through all the layers forming the abdominal wall of the human inguinal area; they arrange interconnected networks in dermis, in external and internal oblique and transversal muscles and in their aponeuroses, as well as in fasciae and in the peritoneum. The lymphatic bed in question changes during ontogenesis. Age transformations of the lymphatic capillaries are in connection with functional loading on the anterior abdominal wall. Intraorganic connections existing between the lymphatic vessels of the anterior abdominal wall and the organs of the small pelvis (urinary bladder, uterus, rectum, etc.) are revealed, they are of a rather great interest for physicians.     

Elasticity of the living abdominal wall in laparoscopic surgery

Laparoscopic surgery requires inflation of the abdominal cavity and this offers a unique opportunity to measure the mechanical properties of the living abdominal wall. We used a motion analysis system to study the abdominal wall motion of 18 patients undergoing laparoscopic surgery, and found that the mean Young's modulus was 27.7+/-4.5 and 21.0+/-3.7 kPa for male and female, respectively. During inflation, the abdominal wall changed from a cylinder to a dome shape. The average expansion in the abdominal wall surface was 20%, and a working space of 1.27 x 10(-3)m(3) was created by expansion, reshaping of the abdominal wall and diaphragmatic movement. For the first time, the elasticity of human abdominal wall was obtained from the patients undergoing laparoscopic surgery, and a 3D simulation model of human abdominal wall has been developed to analyse the motion pattern in laparoscopic surgery. Based on this study, a mechanical abdominal wall lift and a surgical simulator for safe/ergonomic port placements are under development.