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PubMed1994

[Near infrared spectrophotometric monitoring for cerebral ischemia during the occlusion of the internal carotid artery at CEA].

Near infrared spectrophotometry provides noninvasively real-time information on cerebral oxygenation and cerebral blood volume. Using this method of spectrophotometry we investigated the adequacy of collateral circulation during cross-clamping of the internal carotid artery in patients who underwent carotid endarterectomy. In 15 patients, oxy-hemoglobin, deoxyhemoglobin and total hemoglobin were monitored continuously by near infrared spectrophotometry at the ipsilateral frontal area on the operated side. Changes in these parameters following temporary cross-clamping of the internal carotid artery were evaluated. The stump pressure of the internal carotid artery was measured in every patient. Only the maximum decrease in oxy-hemoglobin during cross-clamping of the internal carotid artery correlated significantly with the stump pressure of the internal carotid artery. Changes in oxy-hemoglobin during cross-clamping of the internal carotid artery demonstrated three patterns; no change or minimally decreased (4 patients), decrease with recovery (4 patients), and decrease without recovery (7 patients). The stump pressure of the internal carotid artery in patients who had no recovery of their decreased oxy-Hb was significantly lower than that in any other pattern (p < 0.01, Mann-Whitney U analysis). Patients who experience decrease in oxy-Hb without recovery following cross-clamping of their internal carotid artery may have poor collateral circulation and therefore may develop cerebral ischemia.

Aged↗
PubMed2001

Long-Term surgical outcomes following intraluminal sutureless graft insertion for type A aortic dissection.

The long-term outcome of sutureless intraluminal graft insertion remains unclarified. Therefore, we reviewed the late surgical outcomes of patients who underwent this procedure for acute type A dissection. Between March 1990 and May 2000, 80 patients aged from 36 to 92 years underwent isolated replacement of the ascending aorta for type A acute aortic dissection. The surgical procedures performed were replacement with an intraluminal sutureless graft in 18 patients (group 1) and suturing of the aorta with a conventional Dacron prosthesis in 62 patients (group 2). The cross-clamp, extracorporeal circulation, circulatory arrest, and operation times were significantly shorter in group 1 than in group 2, and the amount of total blood transfusion was also significantly less in group 1 than in group 2. The hospital mortality rates were 11.1% (2/18) in group 1 and 9.7% (6/62) in group 2 (P > 0.999). The 5-year actuarial survival rates (including operative mortality) were 71% +/- 11% in group 1 and 77% +/- 9% in group 2 (P = 0.268). The event-free survival rates at 5 years were 80% +/- 10% in group 1, and 67% +/- 13% in group 2 (P = 0.780). Regarding graft-related complications, long-term follow-up revealed one graft-related death and one reoperation in group 1 (12.5%), and no graft-related complications in group 2 (0%) (P = 0.047). In conclusion, intraluminal sutureless grafts required less blood transfusion, and shorter cross-clamp, extracorporeal circulation, circulatory arrest, and surgery times. However, the procedure did not improve the hospital mortality or long-term outcome. In fact, the rate of graft-related complications was significantly higher in the intraluminal sutureless group than in the sutured group. Therefore, the intraluminal graft insertion technique should be used only under exceptional circumstances.

Acute Disease↗
PubMed1989

[The determinant factors for open heart surgery with non-blood transfusion--analysis by quantitative theory class II].

The serious complications in the field of cardiovascular surgery are the blood transfusion related problems such as post transfusion hepatitis, AIDS, GVHD and immunosuppressed conditions. These problems have not been settled so far. In our department, open heart surgery with non-blood transfusion is the final goal and extracorporeal circulation with non-blood priming has been indicated under normal conditions. However depending on the cases, blood transfusion is definitely required. Under such circumstances, we analyzed the determinant factors as to whether open heart surgery with non-blood transfusion may be indicated or not, according to the formula based on the quantitative theory (class II). Extracorporeal circulation with non-blood priming were indicated on 124 patients in our department, and they were divided into two groups; blood transfusion group (group I): 64 patients, and non-blood transfusion group (group II): 60 patients. These two groups were compared for study in terms of age, preoperative weight, the body surface area, preoperative Ht value, calculated Ht value at the start of extracorporeal circulation, the aortic cross-clamping time, the total extracorporeal circulation time and total bleeding amount. The following are described in the order of importance. 1) Calculated Ht value: more than 30%. 2) The amount of blood loss after ECC is removed: less than 500 ml. 3) Preoperative body weight: more than 50 kg. 4) Preoperative Ht value: more than 40%. 5) The total ECC time: less than 90 min. In addition, prospective factors which should be considered preoperatively are determined in the following orders. 1) Calculated Ht value. 2) Preoperative Ht value. 3) Preoperative body weight.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Transfusion↗
PubMed2006

Biological markers of fetal lead exposure at each stage of pregnancy.

It has been suggested that plasma lead (Pb) represents the fraction of circulating Pb that crosses the placenta. Whole-blood Pb levels, the conventional method for measuring circulating Pb, may not adequately reflect plasma Pb levels. The objective of this study was to assess the relationship between whole-blood and plasma Pb in a cohort of pregnant women. A group of 237 pregnant women, recruited in Mexico City from 1997 to 1999, was studied. whole-blood and plasma lead concentrations were evaluated at 12, 24, and 34 wk of gestation by inductively coupled plasma-mass spectrometry. Data were analyzed using a mixed-effects regression model. An exponential relationship was found between plasma and whole-blood Pb levels and significant modification of the association by stage of pregnancy. The association was stronger in the second trimester relative to the first, and it further increased in the third trimester. The model predicts increased plasma Pb levels for a given whole-blood Pb value as pregnancy advances for whole-blood Pb levels greater than approximately 110 microg/L, but not for blood Pb levels less than 100 microg/L. These findings could be due to physiologic changes during pregnancy, such as decreasing hematocrit, saturation of red cell Pb binding capacity, and increased bone resorption or intestinal absorption. Collectively, these data suggest that at elevated maternal blood Pb levels the developing fetus may be at greater risk of Pb exposure from increased maternal plasma Pb than otherwise predicted from whole-blood Pb levels.

Adult↗
PubMed1980

Characterization of antisera against bovine prolactin for in vivo studies on prolactin function in the rat.

The IgG fraction of rabbit antisera to bovine prolactin (PRL), intended for in vivo studies on the role of PRL in the rat, was prepared and characterized in vitro and in vivo. The antibodies showed a strong reaction with bovine PRL in double diffusion, immunoelectrophoresis, radioimmunoassay and passive haemagglutination using bovine PRL-coated erythrocytes. In indirect immunofluorescence on paraffin sections of bovine pituitary glands the antibodies could be used for the detection of PRL-producing cells. Cross-reaction with rat PRL was observed in passive haemagglutination with rat PRL-coated erythrocytes and in indirect immunofluorescence on rat pituitary gland, but not in any of the other test systems. The ability of the antibodies to neutralize homologous, i.e. bovine, PRL was tested in lactating rats depleted of endogenous PRL by bromergocriptin treatment. The impaired lactation performance of such animals can be restored by substitution with bovine PRL. If the bovine PRL used for substitution was complexed with anti-bovine PRL-IgG, it lost its biological activity. On the other hand, injections of even high amounts of the antibodies into lactating rats failed to reveal any effect on lactation. It is concluded that either the antibodies do not cross-react with circulating rat PRL in contrast to pituitary PRL (preprolactin?) or that the cross-reacting antibody-populations(s) lack(s) the ability to neutralize the biological function of rat PRL.

Animals↗
PubMed2005

High blood pressure is inversely related with the presence and extent of coronary collaterals.

Patients with hypertension have an increased case fatality during acute myocardial infarction (MI). Coronary collateral (CC) circulation has been proposed to reduce the risk of death during acute ischaemia. We determined whether and to which degree high blood pressure (BP) affects the presence and extent of CC circulation. A cross-sectional study in 237 patients (84% males), admitted for elective coronary angioplasty between January 1998 and July 2002, was conducted. Collaterals were graded with Rentrop's classification (grade 0-3). CC presence was defined as Rentrop-grade > or =1. BP was measured twice with an inflatable cuff manometer in seated position. Pulse pressure was calculated by systolic blood pressure (SBP)-diastolic blood pressure (DBP). Mean arterial pressure was calculated by DBP+1/3 x (SBP-DBP). Systolic hypertension was defined by a reading > or =140 mmHg. We used logistic regression with adjustment for putative confounders. SBP (odds ratio (OR) 0.86 per 10 mmHg; 95% confidence interval (CI) 0.73-1.00), DBP (OR 0.67 per 10 mmHg; 95% CI 0.49-0.93), mean arterial pressure (OR 0.73 per 10 mmHg; 95% CI 0.56-0.94), systolic hypertension (OR 0.49; 95% CI 0.26-0.94), and antihypertensive treatment (OR 0.53; 95% CI 0.27-1.02), each were inversely associated with the presence of CCs. Also, among patients with CCs, there was a graded, significant inverse relation between levels of SBP, levels of pulse pressure, and collateral extent. There is an inverse relationship between BP and the presence and extent of CC circulation in patients with ischaemic heart disease.

Aged↗
PubMed2006

Coronary collateral circulation: the effects of smoking and alcohol.

OBJECTIVE: The presence or absence of coronary collaterals is of vital importance during acute ischemia. Smoking and alcohol have been suggested to play a role, but data are scarce. We examined the extent to which smoking and alcohol use affect the presence of coronary collateral circulation. METHODS: Cross-sectional study in 242 patients, admitted for elective PTCA. Smoking was defined as past or current. Pack years were calculated and categorized into never-smokers (reference-category): <10, 10-19, 20-29, and >or=30 pack years. Alcohol consumption was defined as past or current, and categorized into never-users (reference-category): <1, 1-10, 11-20, and >or=21 units per week (UPW). Collaterals were graded with Rentrop's classification. Coronary collateral presence was defined as Rentrop-grade >or=1. RESULTS: Current smoking (odds ratio (OR) 4.17; 95% confidence interval (CI) 1.79-9.71) was positively associated, while pack years of smoking was not related. Current alcohol intake showed a J-shaped tendency with coronary collateral presence, while past moderate alcohol consumption was inversely associated (OR 0.19; 95% CI 0.04-0.98). CONCLUSIONS: Smoking and (to some extent) alcohol use are associated with collateral presence. The results support the view that life-style factors may affect the formation of coronary collaterals in patients with ischemic cardiac disease.

Aged↗
PubMed2004

Major method-specific differences in the measurement of intact parathyroid hormone: studies in patients with and without chronic renal failure.

BACKGROUND: Following the introduction of two-site immunometric assays for parathyroid hormone (PTH), the expectation of good inter-assay agreement has not been fulfilled. The reasons for this may include differences in standardization as well as fragment recognition between the assays. METHODS: PTH values for healthy individuals, patients with renal failure and patients with normal renal function and elevated parathyroid hormone (hPTH) were compared using two commercial two-site immunochemiluminometric assays (Bayer Magic-lite and DPC Immulite 2000). RESULTS: Immulite results had a mean value 50.4% greater than the corresponding Magic-lite values for the whole study population with individual values ranging from 17.5% below to 118.3% above the corresponding Magic-lite value. There was no significant difference in inter-assay bias between patients with renal failure and those with normal renal function, suggesting that variable cross-reactivity with circulating disease-specific PTH fragments was not the primary cause of the observed discrepancy. Cross-reactivity with the synthetic fragment hPTH (7-84) was 34+/-5% for Magic-lite and 62+/-2% for Immulite. We also studied the stability of synthetic hPTH on storage. CONCLUSION: The instability of synthetic hPTH over extended storage periods may affect primary standard material. The consistent inter-assay differences and the over-recovery observed in external quality assessment programmes for the Immulite assay may have best been explained by differences in calibration and the relative cross-reactivities and/or kinetics of the two assay systems for specific parathyroid fragments.

Humans↗
PubMed1991

Administration of prostaglandin inhibitors to the mother; the potential risk to the fetus and neonate with duct-dependent circulation.

Two infants were delivered by urgent Caesarean section at 34 weeks because of fetal distress. One rapidly developed severe cardiac failure and the other marked cyanosis. Their mothers had been prescribed indomethacin and mefenamic acid (Ponstan) to treat premature onset of labour and chronic polyhydramnios, respectively. Both infants had duct-dependent circulations, their cross-sectional echocardiography showing only a small (1-2 mm diameter) patent ductus arteriosus. The early onset and severity of their symptoms suggested that the maternal intake of prostaglandin inhibitors may have deleteriously led to early closure of their ducts, essential in duct-dependent circulations. Although such occurrences are rare, fetal cross-sectional echocardiography should be performed prior to administration of prostaglandin inhibitors during pregnancy.

Cesarean Section↗
PubMed1979

[Extrarenal effects of potassium-canrenoate. Haemodynamic investigations during neuroleptanalgesia in cardiosurgical patients (author's transl)].

Direct cardiac and vascular effects of the antikaliuretic diuretic potassium-canrenoate were measured in cardio-surgical patients during extracorporal circulation and immediatly after operations, each time in neuroleptanalgesia. During "steady state" extracorporeal circulation (aorta cross-clamped, constant flow rate of heart-lung-machine, constant hypothermia), in 13 patients no significant influence on peripheral circulation was found after i.v.-injection of 800 mg potassium-canrenoate. Neither arterial perfusion pressure (representing an arterial vascular reaction) nor changes in oxygenator-volume (indicating venous vasodilation or contraction) demonstrated significant differences in comparison to a control group. After cardiac surgery haemodynamic measurements were performed for a period of 60 minutes in 10 patients given 800 mg potassium-canrenoate. In comparison with a control group (n = 6), no significant differences in arterial pressure, heart rate, cardiac index and pulmonary arterial pressure were found. Left ventricular measurements, using a catheter tip manometer, revealed no direct positive inotropic effect of a single i.v.-injection of potassium-canrenoate. In acute myocardial failure during anaesthesia or in "low cardiac ouptut" following open heart surgery no improvement in myocardial contractility is obtained by i.v.-application of potassium-canrenoate; at the present there seems no alternative to other positive inotropic agents such as calcium, glucagon, dopamine, orciprenaline and epinephrine.

Adolescent↗
PubMedDate not supplied

IL-10 genotype predicts serum levels of adhesion molecules, inflammation and atherosclerosis in hemodialysis patients.

BACKGROUND: Hemodialysis (HD) patients suffer from inflammation and accelerated atherosclerosis that accounts for a large number of premature deaths. The anti-inflammatory interleukin (IL)-10 gene is polymorphic and potential direct effects of IL-10 gene polymorphisms on the circulating serum levels of adhesion molecules, inflammation and atherosclerosis in HD patients still have to be elucidated. METHODS: In a cross-sectional study, circulating serum levels of vascular cell adhesion molecule-1 (VCAM-1), E-selectin (E-selectin), and intracellular adhesion molecule-1 (ICAM-1), serum albumin and C-reactive protein (CRP) were measured in 121 HD patients (70 male and 51 female, with mean age 49 +/- 18 yrs). Carotid artery intima media thickness (IMT) was evaluated by Doppler ultrasonography. Patients were genotyped for the polymorphic base at position -1082 of the IL-10 promoter sequence by polymerase chain reaction (PCR). RESULTS: Circulating serum levels of all three adhesion molecules were higher in patients with -1082/AA genotype (p = 0.001). Higher serum albumin levels together with lower CRP levels were observed in patients with -1082/GG genotype (p < 0.05). Prevalence of atherosclerosis was higher in patients with -1082/AA genotype compared to heterozygous and -1082/GG genotype (41, 34 and 26%, respectively, p = 0.018). CONCLUSIONS: These results suggest that IL-10 gene polymorphism has an effect on inflammatory process and atherosclerosis in HD patients. Endothelial protective functions of IL-10 can modulate the circulating serum levels of adhesion molecules. Therefore, IL-10 gene polymorphism could lead to high or low inflammatory process and consequently, to atherosclerosis. IL-10 genotyping can define a high-risk group for atherosclerosis among HD patients.

Atherosclerosis↗
PubMed1990

Improvement in thoracic aortic pressure after proximal aortic cross-clamping by balloon occlusion of the distal aorta.

Spinal cord hypoperfusion injury is a devastating complication of cross-clamping the proximal thoracic aorta. The collateral circulation around the cross-clamp is generally poorly developed, and the run-off is immense, resulting in extremely low thoracic aortic and spinal cord perfusion pressures. The authors postulated that balloon occlusion of the abdominal aorta might confine this reduced collateral flow around the cross-clamp to the thoracic aorta. In 8 of 16 dogs subjected to aortic cross-clamping of the aorta just beyond the arch vessels, the abdominal aorta was also occluded by a balloon. Thoracic aortic pressure and spinal cord perfusion pressure were significantly higher in the animals with aortic balloon occlusion than in those without balloon occlusion (77 +/- 8 mm Hg versus 26 +/- 1 mm Hg, p less than 0.01, and 67 +/- 8 mm Hg versus 18 +/- 2 mm Hg, p less than 0.01, at 10 minutes after cross-clamping). Abdominal aortic balloon occlusion increases thoracic aortic pressure after the aorta is cross-clamped proximally. Further studies are necessary in primates to assess the effect of this procedure in spinal cord perfusion and the rate of paraplegia.

Animals↗
PubMed1995

Primate erythrocyte (E) complement receptor (CR1) as an anchor site for bispecific-based therapies to clear pathogens or autoantibodies safely from the circulation.

We have prepared cross-linked, bispecific complexes [heteropolymers (HP) and antigen-based heteropolymers (AHP)] that facilitate complement-independent binding of target model pathogens or autoantibodies to primate erythrocytes (E) via complement receptors (CR1). The method is based on using monoclonal antibodies (mAb) specific for CR1 that either are cross-linked to an mAb specific for a prototype pathogen (e.g., IgE) or are cross-linked to an autoantigen (e.g., dsDNA) that is recognized by circulating pathogenic autoantibodies in the autoimmune disease systemic lupus erythematosus (SLE). The underlying assumption in this research is that complexed ligands containing IgG bound to primate E CR1 should be recognized and processed via the same mechanism by which complement-opsonized immune complexes bound to E CR1 are cleared from the circulation and phagocytosed in the liver and spleen. Our work in experimental monkey models has demonstrated that binding of substrates to primate E via this method does indeed lead to the safe and rapid clearance of the target pathogens or autoantibodies from the circulation, without any lysis or loss of the E. Although a number of questions must still be resolved, it may be possible to generalize these findings and use this CR1-based approach to develop a simple noninvasive bispecific therapy that can be used to clear pathogens or autoantibodies from the circulation.

Animals↗
PubMed1984

Enhanced oxygen unloading by an interdimerically crosslinked hemoglobin in an isolated perfused rabbit heart.

Coronary perfusion has shown that an intramolecularly crosslinked hemoglobin (Hb) with a very low affinity for O2 (Hb crosslinked covalently between the beta chains with 2-nor-2-formylpyridoxal 5'-phosphate, HbXL) has several advantages over ordinary Hb. As predicted from in vitro oxygenation curves, much more O2 was unloaded to the heart at three different heart rates, at two perfusion rates, and when the perfusate was equilibrated with 25% as well as 95% O2. In all cases, the improved O2 unloading occurred at higher tissue O2 pressures than with normal Hb. The greater O2 consumption with HbXL was accompanied by better mechanical performance because, after 90 min of perfusion, the HbXL-perfused hearts maintained two-thirds of their original contractility (dp/dt), while that of the Hb-perfused hearts had declined to one-fifth. A special advantage of HbXL is its ability to unload significant amounts of O2 even at low temperature (10 degrees C), in contrast to whole blood. This should make it useful for supporting aerobic metabolism during low-temperature cardioplegia in cardiac surgery and for organ preservation.

Animals↗