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E Riedel

Publications and source records attributed to E Riedel.

At least 19 recordsLinked to original sources
PubMed2006

Prospective, blinded comparison of helical CT and CT arterial portography in the assessment of hepatic metastasis from colorectal carcinoma.

OBJECTIVE: This prospective blinded comparison of helical CT and helical CT arterial portography aimed to detect liver metastasis from colorectal carcinoma. METHODS AND MATERIALS: 50 patients with colorectal carcinoma were evaluated comparing helical CT with helical CT arterial portography. Each imaging study was evaluated on a 5-point ROC scale by radiologists blinded to the other imaging findings, and the results were compared, with the surgical and pathologic findings as the gold standard. RESULTS: Of the 127 lesions found at pathology identified as metastatic colorectal cancer, helical CT correctly identified 85 (69%) and CT portography 96 (76%). When subgroups with lesions <3 cm (48 patients) and patients with maximum tumor size <3 cm (18 patients) were considered, CT portography was always better than helical CT in terms of sensitivity, specificity, positive predictive value, and negative predictive value. ROC analysis adjusting for multiple lesions per patient revealed significantly greater area under the curve (AUC) for the subgroup of lesions <3 cm (CT-AUC of 77% and CT portography AUC of 81%; P = 0.002). CONCLUSIONS: For identification of large metastases, helical CT and CT portography have similar yield. However, for detection of small liver metastases, CT portography remains superior for lesion detectability.

Colorectal Neoplasms↗
PubMed2006

Proven strategies to reduce cardiovascular mortality in hemodialysis patients.

BACKGROUND: In hemodialysis patients, left ventricular hypertrophy (LVH) correlates with mortality. The reason for LVH in uremics is multifactorial. The primary objective of our study was to investigate the effects of a multi-interventional treatment strategy on LVH. METHODS: In 230 ambulatory patients, including patients with coronary artery disease, diabetes, diastolic and systolic dysfunction, we continued optimized cardiac therapy (beta-blockers, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers) with full anemia correction by intravenous epoetin-beta. The dose of epoetin-beta for maintaining target hemoglobin (Hb) was 68 +/- 23 IU/kg/week. Serial echocardiograms were recorded every 3-6 months. The mean observation period was 4.8 +/- 1.2 years. RESULTS: Mean Hb at baseline was 11.2 +/- 2.0 versus 14.1 +/- 1.4 g/dl (p < 0.001) at study end. There was a significant reduction in left ventricular mass index (LVMI: 159 +/- 50.4 vs. 130.2 +/- 42.7 g/m(2); p < 0.001). In a subgroup of 2/3 of the patients, LVMI returned to normal (169 +/- 33 vs. 114 +/- 14 g/m2; p < 0.001). CONCLUSION: Baseline LVMI (p < 0.001), Hb increase (p < 0.03), and triple cardiac therapy (p < 0.03) were significant and independent prognostic factors for a reduction in LVMI. The annual cardiovascular mortality was 5%. Even anemia correction from 12 to 14 g/dl results in further (p < 0.001) regression of LVMI.

Aged↗
PubMed2005

Asymmetric modulation of human visual cortex activity during 10 degrees lateral gaze (fMRI study).

We used BOLD fMRI to study the differential effects of the direction of gaze on the visual and the ocular motor systems. Fixation of a target straight ahead was compared to fixation of a target 10 degrees to the right and 10 degrees to the left from gaze straight ahead, and to eyes open in complete darkness in thirteen healthy volunteers. While retinotopic coordinates remained the same in all fixation conditions, the fixation target shifted with respect to a head-centered frame of reference. During lateral fixation, deactivations in higher-order visual areas (one ventral cluster in the lingual and fusiform gyri and one dorsal cluster in the postero-superior cuneus) and, as a trend, activations in early visual cortical areas were found predominantly in the hemisphere contralateral to the fixation target. We propose that visual processing is performed predominantly in the hemisphere contralateral to gaze direction, even during small gaze shifts into one visual hemifield. The excitability of visual neurons may be modulated depending on eye position to construct a head-centered frame of reference from a retinotopic input, thus allowing perceptual stability of space during eye movements. A further finding was that BOLD signal increases in fronto-parietal ocular motor and attentional structures were more pronounced during lateral than central fixation.

Adult↗
PubMed2004

A cytogenetic method for stacking gene pairs in common wheat.

The potential for non-reciprocal Robertsonian translocations of wheat (Triticum aestivum L.) to assist in the stacking of genes was assessed from a study of their cytological and genetic behaviour. To obtain translocations, a double monosomic (3B+5A; 2n=40=19ii+2i) was crossed reciprocally with a contrasting disomic. Individuals inheriting a broken monosome were identified from the loss of one arm-specific DNA marker coupled with retention of a marker for the opposite arm. No double breaks (potential translocations) were found in 180 cross progeny recovered from pollen of the double monosomic but two instances (loss of 5AL plus 3BS; loss of 5AL plus 3BL) were found in 251 progeny recovered from ovules. Meiotic pairing and multi-color genome-specific fluorescence in situ hybridization (mcGISH) showed that each plant with a double break contained one translocated chromosome between the A and B genomes that had rejoined at the centromere and that formed a trivalent (19ii+ liii) in about 83% of PMC. Most trivalents (approximately 92%) aligned at metaphase in a 'V' configuration(alternate disjunction) while the rest aligned in linear 'I'(adjacent disjunction) or ambiguous 'L' configurations. Genetic analysis of a testcross of these 'fusion monosomics' showed that this preferential co-orientation of the trivalent influenced the assortment of the chromosome arms involved. Loci that were located in the hemizygous ends of the 'V' trivalent showed strong quasi-linkage in that most ovules from the female testcross carried relevant DNA markers either from both standard chromosomes or from neither. This shows that, in most cases, the two standard chromosomes assorted to the same pole while the fused monosome segregated to the opposite pole. For heterozygous loci (present both on the fusion monosome and the standard chromosomes) assortment was either independent or showed partial linkage to the hemizygous arm depending on the reported recombination distance from centromere. Marker assortment was further distorted in male testcrosses and in doubled haploids (made from the fusion monosomics by the maize method) by the strong selective advantage of pollen or haploids that inherited the standard chromosomes rather than the deficiencies. This genetic data shows that under the combined influence of alternate disjunction and natural selection, progeny of fusion monosomics will revert to the standard disomic arrangement, fixing the gene content of both hemizygous arms in the process. Thus, any pair of genes could be targeted for joint fixation by isolating the fusion monosome that will link them temporarily in a segregating population.

Chromosome Mapping↗
PubMed2004

Neo-adjuvant chemotherapy for primary high-grade extremity soft tissue sarcoma.

BACKGROUND: The purpose of this study was to retrospectively analyze the relationship between neo-adjuvant chemotherapy (NAC) and outcome in patients with high-grade extremity sarcomas. PATIENTS AND METHODS: Inclusion criteria were high-grade, deep, >5 cm extremity soft tissue sarcomas. Patients diagnosed between 1990 and 2001 were treated with surgery only (n=282) or NAC containing doxorubicin/ifosfamide/mesna (AIM) (n=74). The stratified Cox proportional hazards model was used to test the effect of NAC on disease-specific survival and recurrence while adjusting for known prognostic factors. RESULTS: NAC was associated with improved disease-specific survival for this cohort of patients (P=0.02). This overall improvement appears to be driven by the benefit of NAC on disease-specific survival for patient with tumors >10 cm. The 3-year disease-specific survival for tumors >10 cm was 0.62 (95% CI: 0.53-0.71) for patients not receiving NAC and 0.83 (95% CI: 0.72-0.95) for patients receiving NAC. CONCLUSION: NAC with AIM was associated with a significant improvement in disease-specific survival in patients with high-grade extremity soft tissue sarcomas >10 cm. These data emphasize the need for further prospective clinical studies of neo-adjuvant or adjuvant chemotherapy for patients with large high-grade extremity sarcomas.

Adolescent↗
PubMed2003

Atherosclerosis: current concepts of pathophysiology and pharmacological intervention based on trial outcomes.

Atherosclerosis related cardiovascular diseases are the leading cause of death in western societies. The clinical manifestations are chronic arterial obstructions or acute arterial occlusions in various vascular territories. The pathogenesis is only understood in part as yet. Arterial wall abnormalities, blood composition abnormalities and hemodynamic alterations are generally accepted to be causative (Virchow's triad). The key role is played by macrophages in the subendothelial space that are activated immunologically by oxidized LDL particles via the scavenger receptor pathway. Recently, endothelial dysfunction due to oxidative stress was identified as a priming factor in the course of the development of atherosclerotic plaques. Shear stress-induced microinjuries of the endothelium in hemodynamically compromised regions together with local coagulation activation associated with microinflammation of the plaque are currently thought to cause plaque rupture. This event is the reason for local clot formation and ultimate organ infarction. Treatment success is still insufficient, however some progress during the last decade is reflected by the improving outcome of atherosclerosis associated cardiovascular diseases. Evidence from clinical trials supports the efficacy of statins, antiplatelet agents, antihypertensive agents if necessary and omega-fatty acids in patients with overt atherosclerosis. The reduction of mortality achieved by those drugs amounts to: omega-fatty acids -21%, statins -16%, anti-platelet agents -14%, treatment of hypertension -13%. It is impossible to calculate the combined effect of these modalities since in each trial participants received co-medication containing agents tested in other trials.

Arteriosclerosis↗
PubMed2002

Homocysteine in chronic renal failure in relation to renal anemia and to oxidative stress parameters 4-hydroxynonenal and malondialdehyde.

Homocysteine serum levels were measured in patients with end-stage renal disease in relation to severity of renal anemia and oxidative stress parameters such as 4-hydroxynonenal (HNE) and malondialdehyde (MDA). The predialytic homocysteine serum levels of the patients are five times as high as in healthy controls. It was found that homocysteine does not correlate to hemoglobin concentration and to oxidative stress, but rather to parameters of nutrition status such as albumine concentration and protein catabolic rate. The homocysteine accumulation represents a cardiovascular risk factor which is statistically independent of oxidative stress, but dependent on nutrition or energy status in patients with chronic renal failure.

Aldehydes↗
PubMed2002

Regression of left ventricular hypertrophy in hemodialysis patients is possible.

Regression of left ventricular hypertrophy in hemodialysis patients is possible. Left ventricular hypertrophy represents the major risk factor for cardiac morbidity and mortality. Therefore, their regression is mandatory. Since the causes of uremia-associated left ventricular hypertrophy are multifactorial, various therapeutic options can be considered: optimal control of arterial hypertension and volume status, optimal correction of metabolic acidosis, best possible correction of hypoalbuminemia and severe secondary hyperparathyroidism, modern pharmacotherapeutic strategy for the treatment of heart failure (use of angiotensin-converting enzyme inhibitors in combination with angiotensin II receptor blockers and beta-blockers) and total correction of renal anemia. Following the proposed therapeutic strategies we could, by using echocardiography, distinguish in 100 hemodialysis patients the following 3 groups (on the average after 1.5 years): 36 patients with initially normal left ventricular mass index (LVMI (g/m2), F < 110; M < 130) maintained normal (group 1); in 31 patients with moderately increased LVMI full regression resulted (group 2); 33 patients with severely increased LVMI (group 3) had to be further divided into 2 sub-groups: 22 patients with significant improvement of LVMI, 11 patients with no, regression. For the first time we were able to show that it is possible to maintain initially normal LVMI during long-term treatment and to achieve complete regression and significant improvement of LVMI in our patients. However, since LVMI requires a long time to develop, a similarly long time must be estimated for its regression. However, 11 patients remained therapeutically resistant. In this group, severe heart diseases were often combined and highly prevalent, including ischemic heart and valve diseases and end-stage dilatative cardiomyopathy. These patients had to be transferred to cardiac surgery. Anemia is considered to be one of the most important factors for the development of left ventricular hypertrophy. Therefore, total correction of renal anemia has to be strongly recommended in addition to other measures of our therapeutic strategy to maintain full or significant regression of left ventricular hypertrophy.

Adolescent↗
PubMed2001

FDG-PET standardized uptake values in normal anatomical structures using iterative reconstruction segmented attenuation correction and filtered back-projection.

Filtered back-projection (FBP) is the most commonly used reconstruction method for PET images, which are usually noisy. The iterative reconstruction segmented attenuation correction (IRSAC) algorithm improves image quality without reducing image resolution. The standardized uptake value (SUV) is the most clinically utilized quantitative parameter of [fluorine-18]fluoro-2-deoxy-D-glucose (FDG) accumulation. The objective of this study was to obtain a table of SUVs for several normal anatomical structures from both routinely used FBP and IRSAC reconstructed images and to compare the data obtained with both methods. Twenty whole-body PET scans performed in consecutive patients with proven or suspected non-small cell lung cancer were retrospectively analyzed. Images were processed using both IRSAC and FBP algorithms. Nonquantitative or gaussian filters were used to smooth the transmission scan when using FBP or IRSAC algorithms, respectively. A phantom study was performed to evaluate the effect of different filters on SUV. Maximum and average SUVs (SUVmax and SUVavg) were calculated in 28 normal anatomical structures and in one pathological site. The phantom study showed that the use of a nonquantitative smoothing filter in the transmission scan results in a less accurate quantification and in a 20% underestimation of the actual measurement. Most anatomical structures were identified in all patients using the IRSAC images. On average, SUVavg and SUVmax measured on IRSAC images using a gaussian filter in the transmission scan were respectively 20% and 8% higher than the SUVs calculated from conventional FBP images. Scatterplots of the data values showed an overall strong relationship between IRSAC and FBP SUVs. Individual scatterplots of each site demonstrated a weaker relationship for lower SUVs and for SUVmax than for higher SUVs and SUVavg. A set of reference values was obtained for SUVmax and SUVavg of normal anatomical structures, calculated with both IRSAC and FBP image reconstruction algorithms. The use of IRSAC and a gaussian filter for the transmission scan seems to give more accurate SUVs than are obtained from conventional FBP images using a nonquantitative filter for the transmission scan.

Aged↗
PubMed2001

Increased reduction of dimethylarginines and lowered interdialytic blood pressure by the use of biocompatible membranes.

Hypertension contributes to cardiac and cerebrovascular complications in HD patients. Endogenous inhibitors of nitric oxide synthase accumulate in renal failure and may interfere with the regulation of vascular tone. We investigated the elimination of asymmetric dimethylarginine (ADMA) by using biocompatible Polyamide Strade mark membranes in low-flux (Polyflux 6L) or high-flux (Polyflux 14S) hemodialysis or hemodiafiltration (HDF) compared with hemodialysis with cellulosic membranes. Removal rates for ADMA, symmetric dimethylarginine (SDMA), and beta2-microglobulin significantly increased in HDF. The plasma total amino acid concentration and the arginine/ADMA ratio increased, and the mean 24-hour blood pressure decreased during the study. In a second study, we investigated whether plasma amino acids and interdialytic blood pressure are influenced by the use of a biocompatible membrane and HDF. Seventeen end-stage renal disease patients were treated for six weeks with hemodialysis using cellulosic membranes, six weeks with low-flux hemodialysis using Polyflux 6L, and six weeks with HDF using Polyflux 14S. Only in the diabetic patients were the hemoglobin concentration (from 10.6 +/- 1.5 to 11.9 +/- 0.6 mg/dL) and hematocrit (from 33.6 +/- 1.9 to 36.2 +/- 1.5%) increased significantly, whereas the mean 24-hour systolic blood pressure decreased (from 154 +/- 22 to 129 +/- 18 mm Hg). No significant changes were observed in nondiabetic patients. We conclude that primarily diabetic patients seem to benefit from the use of biocompatible membranes--most in HDF--after a period of six weeks. The regulation of nitric oxide pathways by ADMA removal and changed ADMA/arginine ratio might be contributing factors. Further prospective studies are required to show whether the long-term application of HDF or other changes of dialysis treatment modalities may help to improve well-being, morbidity, and mortality in hemodialysis patients.

Adult↗
PubMed2000

Long-term outcome of low-grade oligodendroglioma and mixed glioma.

BACKGROUND: Low-grade oligodendrogliomas and mixed gliomas can be indolent and remain unchanged for years. Optimal timing and effectiveness of initial treatment is uncertain and therapy can be associated with toxicity. METHODS: Retrospective review of patients diagnosed between 1979 and 1997 with low-grade oligodendroglioma or mixed glioma. Time to progression, survival, prognostic factors, and treatment toxicities were evaluated. RESULTS: A total of 106 patients (77 oligodendroglioma, 29 mixed glioma) were identified; median age was 36.7 years. Initial presenting symptoms were seizures in 76 (72%) and headache in 11 (10%); tumor was diagnosed as an incidental finding in five patients. Tumor progression was diagnosed in 72 patients (68%). Overall median time to progression (MTTP) was 5.0 years (range 0.5 to 14.2). Median overall survival (OS) was 16.7 years. No prognostic factors reached statistical significance. MTTP and OS were not significantly affected by treatment. Of 62 patients who received radiation therapy, 9 (15%) developed radiation necrosis and 13 developed radiation therapy-related cognitive changes, requiring ventriculoperitoneal shunting in six. Significant myelosuppression was seen in 35 of 76 (46%) patients treated with chemotherapy. CONCLUSIONS: Low-grade oligodendroglioma and mixed glioma have a long median overall survival. There were no apparent differences in either immediate versus deferred treatment or choice of initial therapy on disease-free or overall survival. Chemotherapy was associated with significant acute toxicity in almost one half of patients; radiation therapy produced late neurotoxicity in one third, justifying deferred treatment until clinically necessary.

Adolescent↗
PubMed2000

Does treatment of renal anemia with recombinant erythropoietin influence oxidative stress in hemodialysis patients?

Patients with chronic renal failure (CRF) undergoing hemodialysis (HD) are exposed to constant oxidative stress, as shown by elevated malondialdehyde (MDA) plasma concentrations in HD patients. The aim of our study was to investigate the role of renal anemia in oxidative stress. To this end, MDA and 4-hydroxynonenal (HNE) were measured in three groups of patients. Group I comprised 8 patients with hemoglobin (Hb) < 10 g/dl (mean Hb 8.1 +/- 1.3 g/dl) and group II 8 patients with Hb > 10 g/dl (mean Hb 12.4 +/- 1.9 g/dl). None of these 16 patients had been previously treated with recombinant erythropoietin (rhEPO). Group III comprised 27 patients with mean Hb 10.5 +/- 1.6 g/dl after long-term treatment with rhEPO. The plasma concentrations of both MDA and HNE in all 43 HD patients were significantly higher (p < 0.0001) than in 20 healthy controls (MDA 2.85 +/- 0.25 vs 0.37 +/- 0.03 microM, HNE 0.32 +/- 0.03 versus 0.10 +/- 0.01 microM). Comparison between the three groups showed that the HD patients with Hb < 10 g/dl had significantly higher plasma concentrations of lipid peroxidation products (MDA 3.81 +/- 0.86 microM, HNE 0.45 +/- 0.07 microM) than either HD patients with Hb > 10 g/dl (MDA 2.77 +/- 0.58 microM, HNE 0.25 +/- 0.05 microM) or HD patients treated with rhEPO (MDA 2.50 +/- 0.12 microM, HNE 0.29 micro 0.03 microM). An inverse correlation was also demonstrated between plasma HNE and Hb (r= 0.62, p < 0.0001). It follows that a substantial part of the oxidative stress is due to renal anemia. Treatment with rhEPO can therefore effectively reduce oxidative stress in HD patients.

Adult↗
PubMed2000

Oxidation parameters in complete correction of renal anemia.

UNLABELLED: Chronic hemodialysis (HD) patients are more exposed to oxidative stress, with its adverse impact on many cell functions and not least on patient survival. There is evidence that partial correction of renal anemia by erythropoietin (rhEPO) therapy reduces oxidative stress. The aim of this study was to clarify whether complete correction of renal anemia with rhEPO reduces free radical generation in HD patients and increases antioxidant supply. The following parameters: malondialdehyde (MDA), reduced glutathione (GSH) and glutathione disulfide (GSSG) were investigated in patients with a hematocrit (Hct) normalized on rhEPO therapy (Hct > or = 0.4), and compared with those in anemic patients (Hct 0.3 - 0.39 and Hct < 0.3). The groups were similar in age, sex or body weight. Patients with normal Hct were significantly longer in the chronic HD program (74.0 +/- 70.3 vs. 23.0 +/- 30.9 and 30.6 +/- 34.8 months; p < 0.05) and received significantly lower doses of iron (35.7 +/- 19.5 vs. 55.4 +/- 26.0 and 80.0 +/- 47.1 mg/week; p < 0.05) and rhEPO (68.9 +/- 63.6 vs. 106.5 +/- 63.9 and 152.8 +/- 86.0 IU/kg/week; p < 0.05). MDA levels were significantly lower in the group with normal Hct than in the comparison groups (1.54 +/- 0.27 vs. 1.98 +/- 0.52 and 2.23 +/- 0.93 micromol/l; p < 0.01), but did not differ significantly between the anemic groups. GSH and GSSG concentrations corrected for erythrocyte levels showed no significant differences, but whole-blood levels in patients with Hct > or = 0.4 and 0.3 - 0.39 were significantly higher than in patients with Hct < 0.3 (GSH: 0.97 +/- 0.42 vs. 1.03 +/- 0.38 and 0.62 +/- 0.34 micromol/ml; GSSG: 14.57 +/- 6.06 vs 13.07 +/- 5.18 and 7.28 +/- 3.64 micromol/l; p < 0.05). CONCLUSION: After correction of renal anemia, MDA levels are significantly lower - reflecting decreased free radical generation - than in anemic HD patients. Whole-blood antioxidant capacity is significantly increased. Overall, rhEPO therapy has clearly positive effects on free radical metabolism.

Aged↗
PubMed2000

Long-term effects of rhEPO therapy on erythrocyte rheology in dialysis patients with different target hematocrits.

UNLABELLED: Successful treatment of renal anemia with recombinant erythropoietin (rhEPO) raises the question of whether the renal anemia symptom complex requires complete correction. Current arguments against increasing hemoglobin (Hb) levels above 10-11 g/dl are impaired hemodynamics, increased risk of vascular access occlusion, unmanageable hypertension and dialysis complications. The aim of the study was to determine whether sustained Hb normalization using long-term rhEPO causes hemorheological changes with a potentially negative hemodynamic impact. The study was conducted in 42 rhEPO-treated dialysis patients with stable Hb > 11.0 g/dl for at least 20 weeks. The mean Hb of the total study group was 12.8 1.1 g/dl. To study the effect of Hb as a risk indicator in greater detail, the patients were divided into two groups, with hematocrits above and below 0.40. Hemorheology (erythrocyte deformability and aggregation, plasma viscosity) showed no significant changes, including vs a healthy control group. Throughout the period of increased rhEPO administration, no increase was observed in the incidence of hypertension or vascular thrombosis. CONCLUSION: the marked additional quality-of-life benefit achieved by complete correction of renal anemia harbors no substantial increase in treatment risk.

Adult↗
PubMed2000

Complete correction of renal anemia by recombinant human erythropoietin.

The target-hematocrit (Hct) for the correction of renal anemia by recombinant human erythropoeitin (rhEPO) therapy is discussed controversially. A normalization of the Hct that could lead to a further improvement of the patients status, is often rejected, because of possible side effects as a result of an increase in blood viscosity. Hemodialysis (HD) induces an acute hemoconcentration due to ultrafiltration that might influence these risk factors negatively and therefore conflict with the normalization of Hct. The aim of this study was to investigate the changes in rheological and biochemical parameters in chronic HD patients with a normal initial Hct before hemodialysis. Results in 39 patients are given as mean +/- SD before/after HD: Hct 0.42 +/- 0.05/0.45 +/- 0.05 (p < 0.001), hemoglobin (g/dI) 13.3 +/- 1.0/14.4 +/- 1.3 (p < 0.001), MCV (fl) 99.3 +/- 5.7/99.1 +/- 5.5, MCHC (mM/l) 19.9 +/- 0.6/20.1 +/- 0.6 (p < 0.01), red blood cell (RBC) elongation (%) 60.97 +/- 3.67/60.99 +/- 3.73, RBC aggregation index AI0 0.52 +/- 0.12/0.50 +/- 0.12, AI4 0.52 +/- 0.14/0.51 +/- 0.12, plasma viscosity 1.74 +/- 0.14/1.92 +/- 0.20 (p < 0.001), whole blood viscosity (WBV), etaabs.100(mPas) 5.91 +/- 0.78/6.80 +/- 1.2 (p < 0.001), etaabs.0.01(mPas) 75.81 +/- 35.48/167.656 +/- 98.686 (p < 0.05), ultrafiltration (FM) 2.1 +/- 1.1. The biochemical parameters protein, albumin, IgG, IgA, IgM, cholesterol, transferrin and fibrinogen are significantly increased after HD. The hemoconcentration during HD is associated with a significant increase in WBV, mainly associated with the increase in Hct (r = 0.83), but not exceeding the normal range compared to healthy controls. The increase in plasma viscosity is correlated mainly with an increase in protein (r = 0.80), albumin (r = 0.74), and fibrinogen (r = 0.54). No significant changes in RBC aggregation and deformability were observed during the HD session. In conclusion, from the rheological point of view it is unlikely that the normalization of the Hct will contribute to an increased risk in access thrombosis or thromboembolic events in HD patients.

Anemia↗
PubMed2000

Amino acid and alpha-keto acid metabolism depends on oxygen availability in chronic hemodialysis patients.

Amino acid and alpha-keto acid metabolism depends on oxygen availability in chronic hemodialysis patients. Malnutrition in hemodialysis (HD) patients with renal anemia is reflected in an abnormal plasma amino acid profile. We wished to determine the extent to which malnutrition can be improved by correcting anemia with recombinant human erythropoietin (rhEPO) and supplemental iron. As specific parameters we measured and compared the plasma concentrations of the branched-chain amino acids valine, leucine and isoleucine and their transamination products - major participants in proteolysis and protein biosynthesis - using HPLC with fluorescence detection in 45 severely anemic HD patients (group A: Hb 7.2 +/- 0.8 g/dl), 34 patients with partially corrected anemia (group B: Hb 10.3 +/- 0.6 g/dl) and 35 HD patients with totally corrected anemia (group C: Hb 13.5 +/- 0.7 g/dl). Sixty healthy subjects (group N: Hb 14.2 +/- 1.1 g/dl) served as controls. Correlating with the degree of correction (A/B/C/N), a significant shift to anabolic metabolism was observed in the plasma levels of valine: 130/146/155/205 micromol/l; leucine: 73/71/80/110 micromol/l and alpha-ketoisocaproate (KIC): 11.4/11.8/15.1/ 30.4 micromol/l. It is concluded that energy metabolism becomes increasingly anabolic as hemoglobin levels are normalized.

Amino Acids, Essential↗
PubMed1999

A retrospective investigation of an intensive outpatient substance abuse treatment program.

Outpatient treatment for chemical dependency has been found to be both clinically effective and cost efficient. The purpose of this retrospective investigation was to evaluate program completion data and variables related to attrition for an intensive outpatient substance abuse treatment program. Subjects were 488 clients enrolled in the Smithers Evening Rehabilitation Program between 1991 and 1995. Client drug preference was found to be an important factor related to treatment retention, with cocaine abusers having the highest attrition rates. In addition, increasing age was an advantage in predicting who would complete the initial phase of treatment. Implications for programmatic changes, clinical practice, and future research are considered.

Adult↗