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PubMedDate not supplied

Cadherin-6 gene expression in conventional renal cell carcinoma: a useful marker to detect circulating tumor cells.

BACKGROUND: Dissemination of cancer cells into the circulation is an essential step in the development of a metastasis. Detection of circulating cancer cells may improve the monitoring methods for cancer patients. However, the detection of circulating renal cancer cells is mainly hampered by the lack of markers available for renal cell carcinoma (RCC). In this study, we evaluated cadherin-6 mRNA as a new molecular marker for the detection of circulating renal cancer cells. MATERIALS AND METHODS: Forty-six blood samples of conventional RCCs were included. A standard protocol of RT-PCR, assisted by computer densitometric analysis to establish a cut-off, was performed to examine cadherin-6 mRNA expression by using specific primers. A renal cancer cell line, SKRC-59 and forty tumor biopsies from conventional RCCs were used as positive controls. Twenty-five blood samples from non-RCC patients were also analyzed. RESULTS: Cadherin-6 mRNA could be detected in 38140 (95%) conventional RCC specimens. Cadherin-6 mRNA was positive in 21/46 (45.7%) blood samples of RCC patients, while no positivity was found in non-RCC blood samples. Among the localized RCCs, 14/35 (40.0%) blood samples were positive while 7/11 (63.6%) were positive among the blood samples from metastatic RCCs. CONCLUSION: Our data indicate that cadherin-6 gene is frequently expressed in conventional RCCs. Cadherin-6 is a useful molecular marker to detect the circulating cancer cells disseminated from conventional RCC.

Biomarkers, Tumor↗
PubMed2005

Non-invasive measurement of circulation time using pulse oximetry during breath holding in chronic hypoxia.

Pulse oximetry during breath-holding (BH) in normal residents at high altitude (3510 m) shows a typical graph pattern. Following a deep inspiration to total lung capacity (TLC) and subsequent breath-holding, a fall in oxyhemoglobin saturation (SaO(2) is observed after 16 s. The down-pointed peak in SaO(2) corresponds to the blood circulation time from the alveoli to the finger where the pulse oximeter probe is placed. This simple maneuver corroborates the measurement of circulation time by other methods. This phenomenon is even observed when the subject breathes 88% oxygen (PIO(2) = 403 mmHg for a barometric pressure of 495 mmHg). BH time is, as expected, prolonged under these circumstances. Thus the time delay of blood circulation from pulmonary alveoli to a finger is measured non-invasively. In the present study we used this method to compare the circulation time in 20 healthy male high altitude residents (Group N with a mean hematocrit of 50%) and 17 chronic mountain sickness patients (Group CMS with a mean hematocrit of 69%). In the two study groups, the mean circulation time amounted to 15.94 +/-2.57 s (SD) and to 15.66 +/-2.74 s, respectively. The minimal difference was not significant. We conclude that the CMS patients adapted their oxygen transport rate to the rise in hematocrit and blood viscosity.

Acclimatization↗
PubMed2006

[Differences of Angiotensin II receptor expression between systemic and pulmonary circulation in children with left-to-right shunt congenital cardiac lesions].

OBJECTIVE: It has been shown that angiotensin converting enzyme inhibitors (ACEI) can reduce the ratio of pulmonary and systemic circulation blood flow (Qp/Qs) and thus decrease the blood flow of left-to-right shunt in children with left-to-right shunt congenital cardiac lesions. This suggests that there are differences in the expression of Angiotensin II receptors between systemic and pulmonary circulation. This study aimed to explore the differences of Angiotensin II receptors type 1 and type 2 (AT1 and AT2 receptors) expression between systemic and pulmonary circulation in children with left-to-right shunt congenital cardiac lesions. METHODS: Lung and skeletal muscular tissues were obtained from 20 children with left-to-right shunt congenital cardiac lesions by biopsy during operation. The specimens were stained by immunohistochemistry techniques for AT1 and AT2 receptors. The technique of morphometric analysis was used to measure the immunoreactivity of AT1 and AT2 receptors (expressed by IOD values) of pulmonary, skeletal muscular and pleural small vascular wall the diameter of which was 15-100 microm. RESULTS: The immunoreactivities of AT1 and AT2 receptors of pulmonary small vascular walls [(124 +/- 95)x10(3) and (85 +/- 62)x10(3) respectively] were significantly lower than those of skeletal muscular [(219 +/- 156)x10(3) and (155 +/- 139)x10(3) respectively] and those of pleural small vascular walls [(279 +/- 191)x10(3) and (175 +/- 128)x10(3) respectively] in children with left-to-right shunt congenital cardiac lesions (P < 0.05). CONCLUSIONS: The expression of AT1 and AT2 receptors in small vascular walls of systemic circulation was higher than that of pulmonary circulation in children with left-to-right shunt congenital cardiac lesions.

Child↗
PubMedDate not supplied

Renal pathomorphology and histochemistry in dog after hemodilution as well as after administration of full blood in extracorporeal circulation in dog.

Dog kidneys were studied morphologically and histochemically after hemodilution to a 10--20% hematocrict value and transfusion of whole blood under conditions of extracorporeal circulation ensuring constant (linear) flow. Marked interstitial edema in the dog kidneys after hemodilution was the most pronounced alteration, attributed to disorders in the capillary circulation depending upon the apparatus employed. This conclusion was supported by similar changes in animals subjected to various degrees of hemodilution. Widening of the glomerular space and compression of renal tubules were the direct consequences of interstitial edema. Histochemical reactions revealed damage of the cell membranes. Swelling of the ergastoplasm and lysosomes was interpreted as secondary to disorders in circulation of tissue fluid. The least pronounced changes concerned the mitochondria. After extracorporeal circulation with whole blood, thrombi and fat emboli were observed in the blood vessels of the renal glomeruli, attributable to damage of blood in the extracorporeal circulation apparatus.

Adenosine Triphosphatases↗
PubMed1990

[Energy metabolism of the brain, detected with 31-P magnetic resonance spectroscopy during extracorporeal circulation in the rabbit].

The question of a possible brain damage during open heart surgery using extracorporeal circulation is still a problem, especially in infants with circulatory arrest under deep hypothermia. During the last years Magnetic Resonance Spectroscopy was developed, and with this method we have now a possibility to study brain energy metabolism non-invasively and continuously. Our aim was to develop an animal model (rabbit) for studying brain energy metabolism by 31-P Magnetic Resonance Spectroscopy during extracorporeal circulation. In a first step we have shown that the influence of hypothermia on energy metabolism in the brain can be measured in the intact animal by MR-Spectroscopy. In a second step a non-magnetic heart-lung machine for rabbits was constructed and is described here. We get a completely normal brain spectrum in the beginning and after two hours of extracorporeal circulation. The spectrum is also normal on extracorporeal circulation at 35 degrees C and during cooling down to 18 degrees C. With this animal model it will be possible to study different variables of extracorporeal circulation such as duration of circulatory arrest under deep hypothermia or changes of the priming including pharmacological changes.

Adenosine Triphosphate↗
PubMed1990

The influence of extracorporeal circulation and hemoseparation on red cell deformability and membrane proteins in coronary artery disease.

Extracorporeal circulation and hemoseparation may lead to coupled mechanical and chemical blood trauma and thus influence red cell deformability. Ten patients with coronary artery disease underwent coronary bypass. Patients' blood samples were drawn preoperatively, after extracorporeal circulation, and after hemoseparation. Ten healthy adults served as control subjects. Red blood cell deformability was determined by direct microscopic observation of red blood cells subjected to shear stresses of 1.2 to 13.3 Pa with a counter-rotating rheoscope. Red cell membrane proteins were separated by one-dimensional polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. At 1.2 Pa, preoperative red cell deformability was significantly greater in patients with coronary artery disease than in control subjects. Neither extracorporeal circulation nor hemoseparation changed red cell deformability significantly. Electrophoretic separation of membrane proteins failed to show any quantitative or qualitative differences between patients and control subjects. Moreover RBC membrane proteins of red blood cells in the patients were not altered as a result of extracorporeal circulation or hemoseparation. The preoperatively increased red cell deformability in the patients may be drug-induced. Our data suggest that the extracorporeal circulation and hemoseparation techniques used in this study do not lead to red blood cell damage.

Blood Transfusion, Autologous↗
PubMed1988

Enterohepatic circulation of newly administered alpha-tocopherol in the rat.

We have measured the magnitude of the enterohepatic circulation of newly administered [3H]-alpha-tocopherol in rats. One group of animals (day-1 rats) was used to prepare [3H]-alpha-tocopherol-containing lymph. Another set of animals (day-2 rats) was divided into control and vitamin E supplemented (+E) groups, which were used to study the enterohepatic circulation of [3H]-alpha-tocopherol from day-1 rat lymph administered into the jugular vein of day-2 rats. Mesenteric lymph duct and common bile duct cannulations were performed. The enterohepatic circulation in day-2 rats of intrajugularly administered [3H]-alpha-tocopherol in chylomicrons was found to be 1.78 +/- 0.23% for control and 0.98 +/- 0.08% for +E rats (p less than 0.01). A considerable quantity (13.3 +/- 4.3% in control vs 19.2 +/- 4.7% in +E) of [3H]-radioactivity was recovered in bile over 24 h, of which pure [3H]-alpha-tocopherol was 3.17% in control and 1.04% in +E bile. More than 95% of [3H]-radioactivity recovered in day-2 control and +E bile was more polar than alpha-tocopherol shown by high performance liquid chromatography (HPLC). In contrast, more than 95% of [3H]-radioactivity appearing in day-2 lymph was unchanged alpha-tocopherol. Thus, the magnitude of enterohepatic circulation of alpha-tocopherol is very small in rats. Quantitation of the enterohepatic circulation of vitamin E under different physiological conditions remains to be investigated.

Animals↗
PubMedDate not supplied

[Neurologic complications after extracorporeal circulation in the light of experimental studies].

On the basis of experimental investigations the authors describe the causes of certain complications after extracorporeal circulation. The experiments were carried out in 11 sheep. The duration of extracorporeal circulation was from 1 to 2 hours. It was found that the intracranial pressure, which is an indicator of intracranial expansion, increased with increasing time of cannule introduction into the heart and veins, with the volume of perfusing fluid given during the procedure, with falling value of the arterial blood pressure and impairment of venous return. The intracranial pressure increased also with the duration of extracorporeal circulation. Falls of the arterial blood pressure and venous return occurred simultaneously with impairment of the cerebral blood flow causing cerebral hypoxia. The results of histological examinations of brain tissue were consistent with central nervous system hypoxia, and showed also that these changes developed within the first hour of extracorporeal circulation. The complications arising after extracorporeal circulation may be due to brain oedema. Thus it would be recommendable to pay attention during preoperative management of the patients to the possibility of brain oedema as a complication of the procedure.

Animals↗
PubMed1987

[Adrenal circulation of rabbits in hemorrhagic and endotoxin shock].

Tissue circulation of the adrenal gland which is known as antishock organ was investigated by the hydrogen clearance method in hemorrhagic and endotoxin shock using rabbits. Mean blood pressure was maintained at 35 mmHg for two hours in the hemorrhagic group, while 2mg/kg of endotoxin was injected intravenously in the endotoxin group. The data obtained were as follows: Adrenal tissue circulation and renal circulation were reduced to 40% and 14.9%, respectively in the hemorrhagic group and reduced to 69% and 48%, respectively in the endotoxin group. Plasma corticosterone concentration was significantly elevated in both groups. Plasma beta-glucuronidase was significantly elevated in both groups and most animals died within 72 hours. From these data we concluded that adrenal circulation was distributed preferentially at the sacrifice of renal circulation in the shocked state.

Adrenal Glands↗
PubMed1986

Arteriovenous shunt-circulation in lymphoedematous limbs.

In lymphoedema of the extremities arteriovenous shunt circulation develops. Regulation of limb circulation was studied in 28 cases of (primary and secondary) lymphoedema by using the venous isotope dilution method and technetium-macroaggregate perfusion scintigraphy. As a result of lymphoedema, limb circulation (total limb circulation) increases, arteriovenous O2 difference is low and the O2 uptake of the tissues is normal. The development of arteriovenous (micro-, and macro-) shunts can be directly visualized by perfusion scintigraphy. In lymphoedema of the extremities the nutritive--capillary--blood supply of the tissues remains normal and therefore, no trophic disturbances develop. Lymphoedema is often associated with a fairly considerable arteriovenous shunt circulation and, in such cases, the cardiac output as well as cardiac performance are enhanced.

Adult↗
PubMed1986

Quantitative analysis of the contribution of pulmonary and hind limb circulation to the clearance of exogenous catecholamines.

The contribution of pulmonary and hind limb circulation to the clearance of exogenous catecholamines was analyzed quantitatively. During infusion of clinical doses of norepinephrine, epinephrine and dopamine in dogs, the plasma level of catecholamine and the plasma flow were measured simultaneously. Percentage of contribution was calculated from the following equation; transorgan difference of plasma catecholamine (nanograms per milliliter) X plasma flow (milliliters per minute) X 100/dose (nanograms per minute). This value means the percentage of the amount of catecholamine cleared by an organ to the amount of catecholamine administered into the body. Small but significant transpulmonary gradients of plasma levels of norepinephrine, epinephrine and dopamine and large translimb gradients of plasma levels of these catecholamines were observed. The plasma flow of pulmonary circulation was increased by infusion of epinephrine and dopamine, whereas it remained unchanged by infusion of norepinephrine. The plasma flow of hind limb circulation showed no significant change by infusion of catecholamines. The calculated contribution values indicate that pulmonary circulation clears 35.7% of norepinephrine (at 0.2 ng X kg-1 X min-1), 27.1% of epinephrine (0.2 ng X kg-1 X min-1) and 21.5% of dopamine (10 micrograms X kg-1 X min-1) administered exogenously, and that the corresponding figures for hind limb circulation are 8.2, 7.8 and 4.5%.

Animals↗
PubMedDate not supplied

Role of enterohepatic circulation in the analgesic action of 1-alpha-acetylmethadol in the rat.

The enterohepatic circulation of 1-alpha-acetylmethadol (LAAM) was investigated in the rat. Bile containing 3H-LAAM metabolites was collected from a biliary cannulated donor rat after administration of 3H-LAAM (5 mg/kg, 15 muCi/kg, sc) and infused into the intestine of a double biliary-cannulated recipient rat for 1 hr, and tritium excreted into the bile of the recipient rat was monitored. Within 1 hr after the end of infusion significant radioactivity was found in the bile of the recipient rat and by 10 hr 50% of the infused dose of 3H had been re-excreted into bile. The contribution of enterohepatic circulation of LAAM metabolites to the analgesic action of LAAM was also assessed. Pretreatment of rats with neomycin sulfate was used as a method of decreasing enterohepatic circulation of biliary glucuronide conjugates of LAAM metabolites, and such pretreatment had no effect on LAAM analgesia (6 mg/kg) measured by the hot-plate method. In rats with a biliary fistula, a situation in which enterohepatic circulation was completely eliminated, the analgesic response to a dose of LAAM (6 mg/kg, sc) was not different from sham-operated control group. The above findings indicate that enterohepatic circulation of LAAM metabolites does not contribute to the intensity or duration of LAAM analgesia.

Analgesics↗
PubMed1978

[Role of GABA and its derivatives in regulating cerebral circulation].

GABA, its derivative -- gamma-hydroxybuturic acid and metabolite --succinic acid have a pronounced dilatatory activity on cerebral circulation in various brain parts. GABA increases cerebral circulation by 25.3%, gamma-hydroxybutyric acid by 35.9% and sucinic acid by 20.4%. In ischaemia of the brain a relationship has been established between cerebral circulation, changes in the GABA system in brain and in the walls of cerebral arteries. The content of GABA increases following enhancement of GAD activity and inhibition of GABA-T. The increase of endogenous GABA level in brain during hypoxia of the brain brings to an improvement of blood circulation through increasing collateral vessels. Experiments with GABA-T inhibition by aminooxyacetic acid give direct evidence about the role of the GABA system in cerebral blood circulation. This mechanism is evaluated by us as an example of an autoregulatory system that is realized by a feed-back mechanism providing the adaptability and compensatory function of cerebral haemodynamics to changing conditions.

4-Aminobutyrate Transaminase↗
PubMed1984

Distribution of innervation and circulation in porcine cervical trachea.

The circulation and innervation to porcine cervical trachea were studied in 54 animals in situ. The antemortem response of porcine tracheal muscle was measured isometrically during selective injection of acetylcholine into the cranial thyroid arterial circulation. A predominantly unilateral (70.4%), rather than bilateral (3.7%), arterial circulation was identified; a cranial thyroid artery was not demonstrated in 25.9% of swine, suggesting dominant perfusion from the caudal thyroid circulation. After animals were killed, dye injection through the dominant cranial thyroid trunk demonstrated homogeneous perfusion of the muscle in all instances. In 20 of these animals, the distribution of parasympathetic innervation to porcine tracheal muscle was studied by selective electrical stimulation of the vagus nerves in situ. Tracheal smooth muscle response was measured isometrically, using settings (20 v, 20 Hz) causing maximal contractile force. Bilateral electrical stimulation caused active tracheal tension of 23.2 +/- 1.9 g/cm. Unilateral stimulation of the left vagus nerve caused 17.8 +/- 1.5 g/cm contraction, which was significantly greater than the response caused by selective stimulation of the right vagus nerve (12.1 +/- 1.6 g/cm; P less than 0.001). Innervation to porcine cervical trachea, although bilateral, is derived predominantly from the left vagus nerve; circulation is derived almost always from the left cranial thyroid artery.

Acetylcholine↗
PubMed1984

[Homologous plasma cross-circulation on galactosamine induced hepatic failure rats].

Plasma cross-circulation which resembles plasma exchange clinically was carried out in between galactosamine (GalN) treated hepatic failure rats and normal rats. Twenty-four hours after the injection of GalN, plasma cross-circulation was performed at a plasma flow rate of 0.1 ml/min for 6 hours. In eighteen hours after the completion of a procedure, survival rate was 75% (6 out of 8 survived) in GalN injected rats treated with plasma cross-circulation, as compared to 40% (4 out of 10 survived) in GalN injected rats treated with sham-circulation. State 3 oxygen consumption and ATP synthesis in the liver mitochondrial respiratory function, and ATP and total adenine nucleotide contents in the liver in the former group were significantly higher than those in the latter group at the time of sacrifice of the survived animals. These appear to suggest that plasma cross-circulation enhances mitochondrial phosphorylative activity in the liver and may contribute higher survival rate of the rats. Plasma exchange using a large amount of fresh plasma, therefore, would be effective for the treatment of acute liver failure in its early stage.

Animals↗
PubMed1978

The pulmonary circulation in congenital heart disease. II. Pulmonary hypertension.

In young children with congenital heart disease the pulmonary circulation is exposed to abnormal haemodynamic conditions before it is fully developed. In the newborn infant the persistence or development of pulmonary hypertension rapidly leads to structural change. The speed with which an increase in muscularity can develop has hitherto been underestimated. In most children dying in early infancy with congenital heart disease and pulmonary hypertension the presence of thick walled small arteries is due not to persistence of the high wall thickness of foetal life, but to a rapid postnatal response of the pulmonary circulation to pulmonary hypertension. In older patients with a ventricular septal defect, aged between 3 months and 4 years, the presence of pulmonary hypertension has been shown to interfere with the growth and development of the pulmonary circulation, judging this by reduction in size and multiplication of intra-acinar arteries and an increase in muscularity of both pre and intra-acinar arteries and veins. In these patients elevation of pulmonary vascular resistance was associated with failure of the intra-acinar pulmonary circulation to develop normally and not with obliterative pulmonary vascular disease. Recent studies indicate that growth and development of the peripheral pulmonary circulation can be quantitated in lung biopsies taken from infants and young children with congenital heart disease. It should therefore be possibe to correlate structure and function at a critical period of lung development, before the changes of obliterative pulmonary vascular disease are established.

Aortic Coarctation↗
PubMed1980

[Antibiotic concentration during extracorporeal circulation (author's transl)].

In open surgery, ampicillin (Solcillin) or cephacetrile (Celtol), 2 g for patients weighing 20 kg or more, and 1 g for those below 20 kg, was administered, and the antibiotic concentrations in blood and urine were estimated during extracorporeal circulation, from the time of operation to the admission in an intensive care unit (Group A). In other group, a total circulation volume of 0.3 mg/ml of the antibiotic was administered, based on body weight of patients and priming volumes (Group B). In Group A, blood concentration of antibiotics was so variable that it was difficult to decide additional dosage. In Group B, comparatively definite concentrations were estimated in each case. In extracorporeal circulation for a long time, it is preferable to maintain the blood concentration of antibiotic at 50 micrograms/ml, by additional antibiotic administration 90 approximately 120 minutes after the beginning of the extracorporeal circulation. In patients with preoperative subacute bacterial endocarditis, the blood concentration should be kept over 100 micrograms/ml during extracorporeal circulation.

Adolescent↗
PubMed1995

The clonal nature of circulating Sezary cells.

To determine if circulating Sezary cells can be classified as reactive or neoplastic based on the ability to detect the presence or absence of clonal T-cell receptor beta chain (TCR-beta) gene rearrangements by Southern blot analysis, we evaluated the peripheral blood of 25 patients: 11 patients with Sezary syndrome (SS), 11 with benign inflammatory dermatoses (BID), and three normal controls. Three of 11 patients with SS, with Sezary counts ranging from 14% to 52%, did not demonstrate any clonal TCR-beta gene rearrangements in the peripheral blood, despite a TCR-beta rearrangement by Southern blot analysis in the skin. Ten of 11 BID patients and all normal controls showed no evidence of a TCR-beta gene rearrangement in the peripheral blood. However, one patient with psoriasis demonstrated a TCR-beta gene rearrangement in the peripheral blood. The TCR-beta gene rearrangement detected in this patient, confirmed with polymerase chain reaction (PCR) amplification of the TCR-gamma gene rearrangement, did not correlate with the presence of circulating Sezary cells or the increased risk of neoplasia. Our results indicate that circulating Sezary cells may be monoclonal (neoplastic) or polyclonal (reactive), as defined by TCR gene rearrangement studies. Circulating Sezary cells in SS may be reactive in nature and not accurately reflect the actual tumor burden in the peripheral blood. The presence of circulating Sezary cells or the presence of a clone of cells defined by TCR-beta gene rearrangement in the peripheral blood is not limited to neoplastic disease processes.

Adult↗