Oxygen supply to isolated rabbit heart during its perfusion with eryhem and blood

Coronary vessels of the isolated rabbit heart were perfused with eryhem--a solution containing 2.5--3.0 g% of hemoglobin and with the rabbit own blood diluted to the Hb content corresponding to such in eryhem. The oxygen capacity of eryhem as per 1 g of Hb constituted 72% only of the oxygen capacity of erythrocyte Hb. It was shown that eryhem was capable of uptake, transportation and of giving up oxygen. At the same time the myocardium perfused with eryhem was in worse conditions of oxygen supply than the muscle perfused with blood. The required level of oxygen uptake was reached with the increase of coronary blood supply and more complete utilization of blood oxygen reserves.     

Cathepsin B containing cells in the rabbit mesentery during invasion of V2 carcinoma cells

Summary Localization of cathepsin B was studied in the rabbit mesentery during invasion of V2 carcinoma cells. Cathepsin B was visualized immunohistochemically by using monospecific sheep antibodies and the avidin-biotinperoxidase complex (ABC) method. Horizontal and vertical semithin Epon embedded sections of stained mesenteries showed that histiocytes always displayed the strongest staining reaction independently of the presence of V2 carcinoma cells. Fibroblasts, mesothelial cells and the invaded V2 cells were less stained. Strongly stained peritoneal monocytes were frequently found on the surface of the mesentery in association with tumor foxi. The role of these various cathepsin B containing cells with respect to extracellular matrix degradation during tumor invasion in the mesentery is not clear; some aspects of this problem are presented in the discussion.     

Proliferative activity of blood microvascular endothelium of intestinal mesentery during rat postnatal ontogenesis

The study of mitotic activity of mesenteric microvascular endothelium cells (EC) in 4-, 12-, and 30-day old rats has been carried out using following parameters: number of labeled nuclei per vessel, or per 100 microm of vascular length, or per 1 mm2 of endothelial surface area, as well as shares of labeled EC and of vessels with labeled EC, have been estimated. The highest density of labeled nuclei was revealed in the pericapillary vessels in all rats. Its values were significantly higher in 12-day-old rats and were the lowest in 30-day-old ones.     

Controlled substitution with blood products in hemostatic disorders

It is essential for an efficient substitution to define the nature of the defect as good as possible. Simple screening tests allow a rapid classification. Prophylactic substitution is recommended in potentially reversible defects (bone marrow aplasia in connection with leukaemia treatment) and/or imminent bleeding (eventually complicated by additional risk factors). If bleeding cannot be stopped surgically therapeutic substitution is indicated. In case of bone marrow failure, a substitution may be particularly promising. In presence of an increased peripheral platelet destruction (disseminated intravascular coagulation, antithrombocytic antibodies) treatment of the basic disease is mandatory. Combined hemostatic defects can be influenced by fresh frozen plasma (FFP). Fresh whole blood (not older than 48 hours) may be considered in cases of thrombocytopenia and concomitant anemia. For isolated defects (e.g. hemophilias with or without antibodies, congenital afibrinogenemia, lack of factor XIII) special preparations are at hand. The clinical effect of substitution depends on the specific activity of the preparation, on the volume of expansion in the recipient and on other pharmacokinetic factors. Hepatitis and antibody-production may be considered as particularly grave side-effects.     

家兔肠系膜铺片制作间皮改良

利用肠系膜铺片制作间皮,传统的方法取材于大白鼠或蛙的肠系膜,用硝酸银染色后显示出细胞界线,但由于肠系膜为双层结构,细胞界线出现重影,影响观察。曾有人改用蟾蜍腹膜壁层制作间皮铺片,均由于间皮不典型,并有大量色素细胞沉着,其结果不理想。我们对犬、猫、兔几种动物的肠系膜制作间皮进行比较,发现兔的肠系膜结构为单层,染色出现的细胞界线清晰,无色素沉着的影响,为较理想的制作间皮的组织材料     

Capillary blood perfusion during postischemic reperfusion in striated muscle.

Monitoring of nutritive blood flow in muscle is of particular importance to reconstructive surgeons, since ischemia/reperfusion in striated muscle is known to result in postischemic microvascular perfusion failure. Laser Doppler flowmetry has recently been introduced as an easy-to-use, noninvasive technique for continuous monitoring of microvascular tissue perfusion. Despite its popularity, there exists a great deal of controversy as to what actually generates the laser Doppler signal recorded from a given tissue. Intravital microscopy is a technique for direct visualization of the nutritional circulation in tissue. By using intravital microscopy, direct measurements of blood perfusion in individual segments of the nutritional microcirculation can be made. In 22 Syrian golden hamsters we performed laser Doppler flowmetry and intravital microscopy measurements in muscle tissue prior to and during reperfusion after 4 hours of tourniquet ischemia using the dorsal skinfold chamber model. Intravital microscopy (n = 10) revealed a heterogeneous capillary perfusion during the early reperfusion phase with a decrease (p less than 0.01) in functional capillary density to 49.4 +/- 17.0 percent of control. No recovery was observed after 24 hours of reperfusion. Laser Doppler flowmetry (n = 12) showed a parallel reduction of capillary red blood cell flux during the early perfusion phase to 43.9 +/- 22.6 percent of control values (p less than 0.01), and no recovery was observed after 24 hours of reperfusion. However, the laser Doppler flowmetry technique was not able to detect the capillary perfusion inhomogeneities shown by intravital microscopy. Postischemic reperfusion in striated muscle is characterized by a decrease in functional capillary density and a heterogeneous capillary perfusion. Laser Doppler flowmetry is a useful tool for monitoring microvascular tissue perfusion, although in striated muscle of the hamster it must be considered that accurate nutritional "capillary" flow readings can be grossly overestimated if larger vessels, such as arterioles and collecting venules, are contained in the measuring field of the laser Doppler probe.     

Effect of lacrimal plugs combined with deproteinized calf blood extract eye gel for filamentary keratitis

This study aims to investigate the efficacy of lacrimal plugs combined with deproteinized calf blood extract eye gel on the treatment of dry-eye-associated filamentary keratitis. Lacrimal plugs were inserted into both the upper and lower puncta of 15 patients (28 eyes). Deproteinized calf blood cxtract eye gel was applied in two patients who were not cured after this operation. All patients were asked to complete three questionnaires 1 day before the surgery and at 1 week and 1 month after the surgery. Ophthalmologic examinations were carried out and repeated at 1 day and at 1 week and 1 month after plug insertion, which include fluorescein staining, tear break-up time (BUT), Schirmer test I (STI), corneal confocal microscope (HRT-III), and impression cytology (IC). Symptoms were relieved in all patients 1 month after the application of lacrimal plugs. Deproteinized calf blood extract eye gel was applied to two patients whose symptoms remained after lacrimal plug implantation for 1 week. At 3 weeks later, the symptoms disappeared and cornea fluorescein stain was hardly identified. The lacrimal river in all patients became broader after the surgery, 11 of whom reached 0.3 mm. Cornea filamentary disappeared in all patients. The average of BUT and ST were increased to 7.50 ± 1.897 s (p < 0.001) and 8.12 ± 1.996 mm at 1 week after the operation and 7.94 s and 9.00 ± 1.897 mm at 1 month later, respectively. Photography from HRT-III suggested that the state of corneal epithelium was markedly improved, including the squamous metaplasia of the epithelial layer of the cornea and the bend of nerve fibers under the corneal epithelium. IC also suggested that the squamous metaplasia of epithelial layer of conjunctiva in these patients was improved. The symptoms of patients suffering from severe filamentary keratitis were remarkably relieved by using lacrimal plugs, which could increase the tear volume of the ocular surface, improve the condition of tear film, and promote the recovery of corneal diseases. For patients with more severe symptoms, additional usage of deproteinized calf blood extract eye gel could assist the treatment. Therefore, lacrimal plugs combined with deproteinized calf blood extract eye gel are suggested to be an effective method to treat severe filamentary keratitis.     

Continuous hypothermic perfusion of rabbit kidneys.

Addition of cryoprotective agents to whole organs is possible only by vascular perfusion with the cryoprotectant dissolved in a suitable perfusion fluid.Vascular resistance, organ weight gain, release of lactate dehydrogenase (LDH), and post-transplant function was studied during and after hypothermic perfusion at +6 °C of rabbit kidneys with six different perfusion fluids. A mixture of dextran and bovine serum albumin (BSA), BSA alone in various concentrations, and human serum albumin were tested as colloids, and the effect of perfusate osmolality was investigated.The dextran-BSA mixture was found to be superior to 4.5 and 6.0% BSA alone in terms of better perfusion characteristics, better post-transplant function, and lower LDH release. Perfusion characteristics during perfusion with human serum albumin and subsequent graft function were not different from those observed in experiments with dextran-BSA, but the LDH release was lower.Perfusate osmolality was increased by the addition of glucose or mannitol. Perfusion characteristics during perfusion with the hypertonic perfusates were not different from those observed during isotonic perfusion, but post-transplant function seemed to be better after perfusion with the fluid made hypertonic with glucose, whereas addition of mannitol seemed to be deleterious.Thus a perfusion fluid of extracellular electrolyte composition, containing human serum albumin as a colloid and made hypertonic with glucose, can be used as a vehicle for cryoprotectants during their addition to rabbit kidneys.     

Formation of plastic connections of the visual system during ontogenesis of the rabbit

Analysis of evoked potentials and unit activity in the visual cortical projection area of rabbits revealed a definite succession of forming of interneuronal connections in ontogeny. In early postnatal period, the neuronal reactions were characterized by stable responses with one excitatory phase corresponding to initially negative surface evoked potential. Similarity of reactions of neurones situated in the same vertical column was observed and explained by functioning of a system of rigid connections of the thalamic relay nuclei afferents with cortical pyramidal neurones. Beginning from the third week of postnatal life of rabbits the neuronal reactions assumed a distinctly expressed phasic character, and variability of responses was seen along the vertical line. The changes revealed correlated with formation of a system of interneurones providing a possibility of plastic neuronal interaction. A study of the influence of preliminary cortical stimulation of the associative areas showed that intercentral cooperation mediated by cortical interneurones providing a systemic analysis of visual information began to form from the third week of postnatal life and reached the definitive level at later stages of development.