Anatomy of the left atrioventricular valveapparatus in landrace pigs

The aim of this study was to describe the structures and variations of the left atrioventricular valve apparatus in pigs’ hearts. The valve apparatus elements were investigated using morphometric criteria such as the implantation base width, maximum cuspid depth and fibrous ring circumference, and using morphological criteria such as the numbers and sites of the cuspids, tendon cords and papillary muscles. We concluded that morphometric criteria such as the implantation base width and greater cuspid depth could be used to characterize the cuspids of the left atrioventricular valve apparatus; and that morphological criteria such as the number of papillary muscles, fibrous ring circumference and number of tendon cords were generally not associated with the variations in the number of cuspids. We can state that the number of cuspids in the left atrioventricular valve in pigs is variable and that commissural cuspids are frequently present.

Anatomy of the septomarginal trabecula in Landrace pig hearts.

The limitations on the availability of organs for transplantation have aroused interest in research on xenotransplantation of whole organs or certain parts of them. Thus, studies that confirm or reject similarities between the organs of different animals have started to have important clinical applications. In the present study, we investigated the septomarginal trabecula in 34 hearts from Landrace pigs with the aim of observing their similarities with the septomarginal trabecula in humans. In pigs, the muscle bundle of the septomarginal trabecula and the right branch of the stimulating complex are dissociated. The right branch is a narrow bridge that, after going out from the upper part of the interventricular septum, is attached to the upper part of the anterior papillary muscle. On the other hand, the muscle bundle of the septomarginal trabecula is generally a resistant crest that goes from the lower part of the septum to the lower part of the anterior papillary muscle. The septomarginal trabecula presents marked anatomical differences between humans and pigs.

Anatomy of the supraventricular crest in human hearts.

The supraventricular crest is a fleshy trabecula of the right ventricle that has an important function in guiding the blood flow. However, controversy persists regarding its anatomical constitution. In this study, we aimed to investigate its frequency, formation, termination, morphometry, and relationships with the septomarginal trabecula, septal papillary muscle, right atrioventricular ring, and left posterior semilunar valve of the pulmonary trunk valve. Our material consisted of 50 hearts from adult individuals of both sexes that had been preserved in 10% formalin. They were opened along the arterial cone by means of an incision starting at the pulmonary trunk and ending at the right margin. The supraventricular crest was always present. The marginal (right) extremity was formed by two to six muscle bundles that joined together (88%). On the septal (left) side, the single muscle bundle penetrated the interventricular septum directly (88%) or by means of two or three divisions (12%). It could form a septal band (52%) and could pass over the septal papillary muscle (43.5%) or just below it (34.8%). There was a relationship of muscle fibres between these two structures in 64% of cases. Dissection of the septal band demonstrated continuity with the septomarginal trabecula (46%). In 80% of cases, the crest was connected to the right atrioventricular ring and it participated in its outline directly (64%) or by means of muscle expansions (16%). Its muscle fibres bordered the left semilunar valve of the pulmonary valve in 50% of cases. Regarding morphometry, we observed that the length varied little with increasing weight of the heart (22.6%), but the height and width increased markedly with increasing weight of the heart.

The anatomy of the human thyroid veins and its surgical application.

The present study was motivated by the importance of the thyroid veins in surgery in the anterolateral cervical region, particularly in tracheostomies, the need for information on modern diagnostic imaging techniques and the lack of specific publications on the subject. The research was performed on 30 adult human specimens by means of dissection and measurement. The superior thyroid vein was constant, single on both sides (83.3%), with its termination (87.1%) at the internal jugular vein (97.2%), either isolated (29.4%) or with other veins, mostly the lingual vein (52.1%), and was located between 1.0 and 2.5 cm below a plane that passes the upper margin of the hyoid bone. The medial thyroid vein, when present, was not constant (43.3%), was single (96.1%), terminated in the internal jugular vein and was located between 2.0 and 4.0 cm from the mid-sagittal line (84.6%). The inferior thyroid vein was constant (96.7%) and varied in number, with one (62.1%), two (27.6%) or even five occurring, and was formed by the confluence of two primary branches (78.6%) as a result of the abundance of anastomoses coming from the lower and medial parts of the gland. The number of terminations corresponded to the number of veins, at the level of the 5(th) to 8(th) rings in 36.9%, of the 9(th) to 10(th) rings in 34.8% and of the 11(th) to 14(th) rings in 28.3%, and occurred in the right brachiocephalic vein (26.1%), in the left brachiocephalic vein (60.9%) or in both veins (13.0%).

Morphometric study of the tricuspid valve in dogs.

An anatomical study of the tricuspid valve was performed in the hearts of 45 dogs using a method of dissection which preserves the integrity of the valve. Morphometrical criteria such as the width of the cusp base and larger depth of cusp and morphological criteria such as the number of tendinous cords, the perimeter of the fibrous ring and the properties of the papillary muscle were adopted for the characterization of a cusp. The tricuspid valve was not consistent with three cusps, but it was observed to present 2, 4 or 5 cusps in 68% of the cases.

Neurovascular pedicles of the tibialis anterior muscle in children / Pedículos neurovasculares del músculo tibial anterior en niños

The importance of the tibialis anterior muscle in infantile orthopedic transposition surgeries, as in myelomemngoceles, it bases this research about the neurovascular pedicles of the tibialis anterior muscle. The study was conducted on 34 legs of human cadavers that were one year old or younger at the time of death. It was observed that the tibialis anterior muscle most frequently presented from 7 to 10 arterial branches (52.4 percent). In 97.1 percent of cases these branches were derived from the anterior tibial artery. In one case the anterior tibial artery was missing and the muscle was supplied by the fibular artery. Thirty-nine and seven tenths percent of arterial branches entered the superior third of the muscle; the middle third received 40.1 percent of the branches and the inferior third received 20.2 percent of the branches. The deep fibular nerve exclusively supplied the innervation, which in91.2 percent of cases, gave off from 2 to 4 branches to the muscle, mainly to the superior (46.2 percent) and middle third (43.0 percent). Most frequently, there were two neurovascular pedicles supplying the superior third and one supplying the middle third.

La importancia del músculo tibial anterior en cirugías de transposición ortopédica en niños, así como en casos de mielomeningocele, fundamenta su estudio respecto a sus pedículos neurovasculares. El estudio se realizó en 34 miembros inferiores de cadáveres de niños de un año o menos de edad. Se observó que el músculo tibial anterior presentaba con frecuencia 7 a 10 ramas arteriales (52,4 por ciento). En 97,1 por ciento de los casos estos ramos eran derivados de la arteria tibial anterior. En dos casos, la arteria tibial anterior estaba ausente y el músculo suplió su irrigación con la arteria fibular. En relación a la entrada de las ramas, 39,7 por ciento lo hacen en el tercio superior del músculo. El tercio medio recibe 40,1 por ciento de las ramas y el tercio inferior recibe 20,2 por ciento de ellas. El nervio fibular profundo es la fuente principal de inervación, en 91,2 por ciento de los casos provee 2 a 4 ramos para el músculo, de ellos el 46,2 por ciento termina en el tercio superior y el 43 por ciento en el tercio medio. Con mayor frecuencia, existen dos pedículos neurovasculares supliendo el tercio superior y uno supliendo el tercio medio del músculo tibial anterior.

Anatomical indicators of dominance between the coronary arteries in swine.

The interest in experimental use of coronary arteries of swine as a stage towards their application in human hearts justifies the need for obtaining a detailed anatomical understanding of those arteries, particularly to evaluate similarities and differences. However, we did not find any citations about anatomical indicators of coronary dominance among swine in the literature. Many authors have used the crux cordis and the origin of the posterior interventricular branch as references for defining three types of pattern in human hearts: right, balanced and left dominance. We used 30 hearts fixed in 10% formalin from male and female Landrace swine aged five to six months, weighing 80 to 110 kg. The branch corresponding to the subsinuosal interventricular sulcus came from the right coronary artery (96.7%) or from both coronary arteries (3.3%). The subsinuosal interventricular branch presented at least one small branch that went beyond the crux cordis. The apical area presented predominance of the paraconal interventricular (left anterior descending) branch in 43.3%, the subsinuosal interventricular branch in 23.3% and presence of both arteries in 33.3%. The left coronary artery emitted 54.5% of the ventricular branches and the right coronary artery 46.5%. Taking the crux cordis and the subsinuosal interventricular branch as references, the arterial pattern in swine hearts is right dominance. The diversity of the apical pattern and the balance in the distribution of ventricular branches do not allow this to be used as an approach in isolation. The similarities between human and swine hearts also apply to the coronary artery pattern.

The subscapular artery and the thoracodorsal branch: an anatomical study.

The motive for this research was the use of the muscles of the scapular region in transposition, transplantation and reparative surgery and the need for more detailed knowledge of the blood supply to these muscles. In addition, the subscapular arterial tree may be used as a source of microvascular grafts to replace damaged or diseased portions of arteries, particularly in the hand and forearm. The research was conducted on 60 sides of corpses of adults of both sexes. It was noticed that the subscapular artery was present in 96.7% of cases and originated laterally to the pectoralis minor muscle in 76.7% of cases. The average calibre was 5.0 mm, and in 73.2% of cases it measured between 4.0 and 5.9 mm. The average length was 18.0 mm, ranging from 10.0 to 29.9 mm (76.7%). It presented in its course important relations with the axillary nerve (69%) and with the radial nerve (82.8%). Its branches were collateral (subscapular muscle - 61.3%) and terminal (except for the circumflex scapular artery), leading to the following muscles: serratus anterior (43.9%), latissimus dorsi (27.6%), and subscapular (23.3%). The thoracodorsal artery, one of the terminal branches, most frequently showed a calibre of between 2.0 and 3.9 mm (70.3%), collateral branches in 85.0%, was mainly distributed to the subscapular muscle (36.7%) and to the serratus anterior muscle (29.0%) and had terminal branches to the following muscles: latissimus dorsi (44.1%), serratus anterior (40.5%) and the subscapular (12.5%). The serratus anterior muscle received one branch in 39.5% and two branches in 41.9%, while the latissimus dorsi muscle received one branch in 66.7% and two branches in 23.1%.

Comparative PM10-PM2.5 source contribution study at rural, urban and industrial sites during PM episodes in Eastern Spain.

In this study a set of 340 PM10 and PM2.5 samples collected throughout 16 months at rural, an urban kerbside and an industrial background site (affected by the emissions from the ceramic manufacture and other activities) were interpreted. On the regional scale, the main PM10 sources were mineral dust (mainly Al2O3, Fe, Ti, Sr, CaCO3, Mg, Mn and K), emissions derived from power generation (SO4=, V, Zn and Ni), vehicle exhausts (organic and elemental carbon, NO3- and trace elements) and marine aerosol (Na, Cl and Mg). The latter was not identified in PM2.5. At the industrial site, additional PM10 sources were identified (tile covering in the ceramic production, petrochemical emissions and bio-mass burning from a large orange tree cultivation area). The contribution of each PM source to PM10 and PM2.5 levels experiences significant variations depending on the type of PM episode (Local-urban mainly in autumn-winter, regional mainly in summer, African or Atlantic episode), which are discussed in this study. The results show that it would be very difficult to meet the EU limit values for PM10 established for 2010. The annual mean PM levels are 22.0 microg PM10/m3 at the rural and 49.5 microg PM10/m3 and 33.9 microg PM2.5/m3 at the urban site. The natural contribution in this region, estimated at 6 microg/m3 of natural mineral dust (resulting from the African events and natural resuspension) and 2 microg/m3 of marine aerosol, accounts for 40% of the 2010 EU annual limit value (20 microg PM10/m3). Mineral dust concentrations at the urban and industrial sites are higher than those at the rural site because of the urban road dust and the ceramic-production contributions, respectively. At the urban site, the vehicle exhaust contribution (17 microg/m3) alone is very close to the 2010 EU PM10 limit value. At the rural site, the African dust is the main contributor to PM10 levels during the highest daily mean PM10 events (100th-97th percentile range). At the urban site, the vehicle exhaust product is the main contributor to PM10 and PM2.5 levels during the highest daily mean PM events (100th-85th percentile range). Mineral dust concentrations during African dust events accounts for 20-30 microg/m3 in PM10 and 10-15 microg/m3 in PM2.5. During non-African dust events, mineral dust derived from anthropogenic activities (e.g. urban road dust) is also a significant contributor to PM10, but not to PM2.5.

Bulk deposition in a rural area located around a large coal-fired power station, northeast Spain.

This work focuses on bulk deposition in a rural area located around a large coal-fired power station in northeast Spain. Deposition chemistry was characterised by high concentrations of SO(4)(2-), Ca(2+) and NH(4)(+), which were relatively high when compared with other rural areas. Monthly bulk deposition evolution of major ions was the result of two superimposed patterns: one pattern related to the volume of precipitation and the other showed the seasonal influence of the major ionic sources. A major local origin was attributed to bulk deposition of SO(4)(2-), NH(4)(+), and Ca(2+), whereas a relatively higher contribution of an external source was deduced for NO(3)(-), Na(+) and Cl(-). The SO(4)(2-) concentrations showed a significant correlation with the local SO(2) emissions. High levels of Ca(2+) were due to the high alkalinity of soils in the study area, although an external origin was attributed to the frequent air mass intrusions from the Sahara. Sources of NH(4)(+) were related to intensive livestock farming in the area. Total suspended particles exert a marked influence over bulk deposition and neutralisation. Thus, despite the high emissions of SO(2) in the area, neutral pH values have always been attained given that the concentrations of Ca(2+) and NH(4)(+) account for the total neutralisation of NO(3)(-) and SO(4)(2-).