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C Landgren

Publications and source records attributed to C Landgren.

6 recordsLinked to original sources
PubMed2001

Relationship between effective ionic dialysance and in vivo urea clearance during hemodialysis.

Effective ionic dialysance (EID) can be measured from dialyzer inlet and outlet conductivity changes following two steps of dialysate conductivity. Relationships between EID and in vivo urea clearances were studied four times per hemodialysis treatment in eight patients, each undergoing six hemodialysis treatments (192 data sets). Dialyzer blood flow was varied from 190 to 500 mL/min. Dialysate flow was constant (751 to 771 mL/min), and a standard dialyzer (700 HG; Cobe, Lakewood, CO) was used. Double samples were drawn for arterial, venous, and dialysate urea measurements. Two laboratory values were missing. Twelve unreliable laboratory values indicated by divergent results were excluded. Urea clearances were calculated by formulae converting whole-blood to blood-water urea clearances. EID was measured using Diascan (Gambro-Dasco, Medolla, Italy). Mass balance was checked by comparison of dialysate and blood-water urea clearances. Divergent results between dialysate and blood-water urea clearance values led to the exclusion of an additional three laboratory values. A small error (4.2%) in urea mass balance was found (dialysate greater than blood-water urea clearances). A total of 175 data sets were compared. EID showed excellent correlation with blood-water urea clearances (r = 0.92) over the line of identity, with a mean difference of -3.5 mL/min (-1%), and similarly with dialysate urea clearances (r = 0.92; mean difference, -13.4 mL/min; -5%). For both blood- and dialysate-side comparisons, differences increased with greater clearances. Because EID is an effective clearance and urea clearance is a measure of dialyzer clearance, the curves were corrected for cardiopulmonary recirculation; access recirculation was zero (Transonic monitor; Transonic Systems Inc, Ithaca, NY). For cardiopulmonary recirculation correction, cardiac output and access flows were assumed to be 6.4 L and 1.46 L/min. Corrected data show EID correlates with blood-side urea clearance (r = 0.92), with a mean difference of +7.3 mL/min (3.3%), and is constant over the range of clearances. EID correlated with dialysate urea clearance (r = 0.92) with virtually no difference. The difference on the blood side is consistent with the urea mass balance error found. These data indicate that EID using Diascan can provide an accurate indication of effective urea clearances obtained during hemodialysis and is of value in monitoring dialysis adequacy.

Arteries↗
PubMed1998

The mouse chondroadherin gene: characterization and chromosomal localization.

The mouse chondroadherin gene was isolated from a cosmid genomic library by the use of a rat chondroadherin cDNA probe. Southern blot analysis of mouse genomic DNA revealed a simple pattern of hybridization indicating a single copy gene for chondroadherin. The mouse chondroadherin gene encompasses 4.1 kb and consists of four exons separated by one large intron of 1929 bp followed by two smaller introns of 247 and 225 bp, respectively. Most of the translated region, including the start codon and the main part of a leucine-rich region, is contained within the first exon. Two small exons of 164 and 146 bp encode the rest of the protein. Interestingly, 4 bases from the stop codon, in the 3'-UTR, a third intron is located. A putative promoter region of 669 bp was sequenced and shown to contain a potential TATAA-box signal 29 bp upstream of the transcription start site and several recognition sites for transcription factors. The exon/intron organization of the chondroadherin gene differs from those of the other known genes of the leucine-rich repeat (LRR) family in the extracellular matrix. Taken together with comparison of protein sequences of other members of the LRR family in the extracellular matrix, the data suggest that chondroadherin has evolved along a different pathway. The chondroadherin gene was mapped to mouse chromosome 11, near D11Mit14, by single-strand conformation polymorphism linkage analysis.

Amino Acid Sequence↗
PubMed1996

Less infusion pain and elevated level of cancer antigen 125 by the use of a new and more biocompatible PD fluid.

Our objective was to investigate the clinical effect of a less toxic and less acidic peritoneal dialysis (PD) fluid produced in a two-compartment bag (PD-Bio). The study had an open cross-over design in 4 stable patients, where the patient served as his/her own control. After a period of three months using conventional PD fluid the patients were switched to three months on the new PD fluid. Routine blood chemistry and transport characteristics were measured. Cell samples from overnight spent dialysis fluid were analyzed for viability, differential count, release of superoxide radicals, and cancer antigen 125 (CA 125). Subjective patient symptoms and handling properties were investigated by a patient questionnaire. Cancer antigen 125 increased significantly, and patients with discomfort or infusion pain during the control period improved during the PD-Bio period. Patient acceptance with respect to handling of the two-compartment bag was excellent and did not differ from the use of standard bags. No changes were seen in the cell samples from spent dialysate, blood chemistry, or transport characteristics between the two treatment periods. PH in the effluent dialysate was, however, significantly higher for PD-Bio at all times during the two-hour dwell. Our results suggest that a PD fluid produced to minimize the level of toxic glucose degradation products and to obtain a more physiological pH has an impact on CA 125 levels, reduces pain and discomfort in connection with infusion of fluid, and does not influence the transport characteristics.

CA-125 Antigen↗
PubMedDate not supplied

Clinical and physiological effects of a new, less toxic and less acidic fluid for peritoneal dialysis.

OBJECTIVE: To report our first clinical experience with a new continuous ambulatory peritoneal dialysis (CAPD) fluid (PD-Bio), which is nearly devoid of glucose degradation products and has a higher pH (6.3) than conventional peritoneal dialysis (PD) solutions, and to discuss in general terms some acute and long-term effects of conventional acidic solutions containing glucose degradation products. DESIGN: 1) Pilot study on 4 patients investigated using a modified peritoneal equilibration test (PET) and cytobiology parameters. 2) Computer simulation study, assuming that conventional acidic solutions cause vasodilatation and recruitment of capillary surface area initially (during 0-60 minutes) in a PD dwell. PATIENTS: Four stable CAPD patients were chosen in an open cross-over study. After a period of three months using conventional PD fluid, the patients were switched to three months on the new PD fluid. RESULTS: Cancer antigen 125 increased significantly, and patients with discomfort/infusion pain during the control period improved during the period with the new fluid. No significant changes were observed in mass-transfer coefficients or drained volumes with the new solution. PH in the effluent dialysis was, however, higher for PD-Bio at all times during a two-hour dwell. In the computer simulation study, a less acidic solution caused an initially lower rate of glucose dissipation and improved ultrafiltration (UF) after a four-hour dwell, as compared to a conventional PD solution. CONCLUSIONS: A new, differently produced, less toxic and less acidic PD fluid (PD-Bio) seems to be better tolerated than a conventional acidic solution with respect to discomfort/infusion pain. Theoretically, neutralized solutions should show slightly improved UF profiles over conventional acidic solutions, according to the computer simulation analysis. Furthermore, it is speculated that a neutral, less acidic, less toxic fluid would cause less interstitial-mesothelial alterations and less impairment of UF capacity than conventional solutions during long-term CAPD.

CA-125 Antigen↗