Sodium-rich tree ash as a native salt source in lowland Papua

The Gidra-speaking Papuans of the Oriomo Plateau, lowland Papua New Guinea, consume ash of two tree species (Melaleuca sp. andAcacia mangium) as a native salt. The ashes contain 100–200 mg sodium/g ash, which is very much higher than the sodium levels in native plant ashes (except for the swamp herbEriocaulon australe) collected in other regions of the world.     

Use of human amnion for microvascular interpositional grafts

A major problem associated with vascular grafting employing an artificial graft is the inflammatory response provoked by the graft and subsequent complications of classical acute rejection phenomena when the graft is implanted subcutaneously into human volunteers. The favorable results obtained by a preliminary study of subcutaneous implantation of amnion in our laboratory have led us to a prospective study to determine its value as a vascular graft. Tubed conduits of glutaraldehyde-treated amnion were hand constructed of varying diameters and lengths. They were employed as segmental interpositional grafts in experimentally created femoral and aortic arterial defects in Sprague-Dawley rats. Patency rates varied from 60 to 90 percent, with all grafts showing remarkable reendothelialization within 3 to 4 weeks postoperatively. Morphology, antigenic reaction, blood flow, and patency of the different experimental amnion grafts were evaluated and compared to appropriate controls.     

One-stage microvascular transfer of a latissimus flap to the sacrum using vein grafts

A large irradiated wound of the lumbosacral area is covered in one stage with a latissimus dorsi musculocutaneous flap by "extending" the vascular pedicle with 25-cm interpositional vein grafts.     

Morphometry of cat's pulmonary arterial tree

Morphometic data of the pulmonary artery in the cat's right lung are presented. Silicone elastomer casts of cat's right lung were made, and measured, counted and analyzed. The Strahler system is used to describe the branching pattern of the arterial vascular tree. These data are needed for any quantitative approach to the study of the pulmonary circulation. For all the pulmonary blood vessels of the cat lying between the main pulmonary artery and the capillary beds, there are a total of 10 orders of vessels in the right upper lobe, 9 orders of vessels in the right middle lobe and 11 orders of vessels in the right lower lobe. The ratio of the number of branches in successive orders of vessels or the branching ratio, is 3.58. The corresponding average diameter ratio is 1.72, whereas the average length ratio is 1.81.     

Network analysis of an arterial tree

The arterial tree of a Sprague-Dawley rat was casted and carefully mapped with the aim of comparing its network characteristics with those suggested by the classical model of an arterial tree. It is shown that if the tree is to be measured accurately, the concept of 'whole vessels' on which the classical model is based must be abandoned since such vessels do not actually exist in the network, nor can they be accurately defined. The concept of 'vessel segments' is proposed instead and its use is demonstrated. A total of 1313 vessel segments in the arterial tree of the rat are mapped and divided into well defined 'levels'. The length and diameter of each segment are measured and the distribution and averages of these at different levels are presented as indicators of the branching characteristics of the tree.     

Staged transfer of a free microvascular latissimus dorsi myocutaneous flap using saphenous vein grafts

The use of long vein grafts in the axilla adds a new dimension to the versatility of the latissimus dorsi myocutaneous flap. When suitable recipient vessels are not available for a microvascular anastomosis, long vein grafts can be used in the axilla to double the arc of rotation of the flap, allowing it to cover the buttocks, lower torso, and scalp (Fig. 8). A case is presented in which the latissimus dorsi myocutaneous flap was transferred in stages to cover a large radiation ulcer of the right buttock.     

The use of buttermilk as a source of phospholipids

A method for obtaining phospholipids from butter-milk, a by-product of butter making is described. The method consists in coagulating the fat globule membranes with mineral or organic acid, separating the resulted precipitate by centrifugation or filtering, lipid extraction by organic solvents mixture and isolation of phospholipids from the extract by acetone treatment or by column chromatography. Butter-milk, a new source of biological membranes, is characterized by a low cost and accessibility.     

Validation of a patient-specific one-dimensional model of the systemic arterial tree

The aim of this study is to develop and validate a patient-specific distributed model of the systemic arterial tree. This model is built using geometric and hemodynamic data measured on a specific person and validated with noninvasive measurements of flow and pressure on the same person, providing thus a patient-specific model and validation. The systemic arterial tree geometry was obtained from MR angiographic measurements. A nonlinear viscoelastic constitutive law for the arterial wall is considered. Arterial wall distensibility is based on literature data and adapted to match the wave propagation velocity of the main arteries of the specific subject, which were estimated by pressure waves traveling time. The intimal shear stress is modeled using the Witzig-Womersley theory. Blood pressure is measured using applanation tonometry and flow rate using transcranial ultrasound and phase-contrast-MRI. The model predicts pressure and flow waveforms in good qualitative and quantitative agreement with the in vivo measurements, in terms of wave shape and specific wave features. Comparison with a generic one-dimensional model shows that the patient-specific model better predicts pressure and flow at specific arterial sites. These results obtained let us conclude that a patient-specific one-dimensional model of the arterial tree is able to predict well pressure and flow waveforms in the main systemic circulation, whereas this is not always the case for a generic one-dimensional model.