Peritoneal dialysis patient survival: a comparison between a Swedish and a Korean centre.

BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated.     

Glucose concentration in the vitreous of nondiabetic and diabetic human eyes

Glycation (nonenzymatic glucosylation) of collagen may play a role in the primary pathology of the vitreous in diabetes. The extent of glycation is determined by the glucose concentration in the tissue. In this study glucose concentration was assayed in blood and vitreous samples obtained from three patient groups undergoing vitrectomy: nondiabetic patients (ND), diabetic patients with insulin-dependent diabetes mellitus (IDDM) and diabetic patients with non-insulin-dependent diabetes mellitus (NIDDM). In the ND group the glucose concentration in the vitreous (3.5 +- 1.8 mM/1) was always lower than in the blood (9.1 +- 3.5 mM/1). In the diabetic groups the vitreous glucose concentration was, with a few exceptions, generally lower than the blood glucose concentration. The vitreous glucose concentration in these groups was generally higher (IDDM 9.4+-3.3 mM/1, NIDDM 7.2+-3.9 mM/1) than in the ND group, and in 15 specimens exceeded 11 mM/1, a level increasing the probability of collagen glycation in the vitreous of diabetic patients.This study was given financial support by the Herman Järnhardt Foundation, the Inez and Joel Carlsson Foundation and by Diabetesföreningen in Malmö     

Natural killer cell activity and CSF monoamine metabolites in suicide attempters

The aim of this study was to investigate markers of serotonin and immune function in suicidal patients. Cytotoxic activity of natural killer cells (NK) and CD16 lymphocytes were studied in 28 suicide attempters and 26 healthy controls, and related in patients to 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF). Patients with CSF 5-HIAA below the median had significantly lower NK cell activity than other patients. CD16 cell frequency was significantly lower in patients than in controls, and patients also tended to have lower NK cell cytotoxicity than healthy controls. There were no statistically significant correlations between 4-hydroxy-3methoxyphenyl glycol (HMPG), homovanillic acid (HVA), CSF cortisol and NK cell activity. The results support the hypothesis of compromised immune function in suicidal patients with evidence of disordered serotonin function.     

A study of mixing conditions during nitric oxide administration using simultaneous fast response chemiluminescence and capnography

We have evaluated the mixing properties of nitric oxide in inspired gases for five different administration techniques. Nitric oxide and carbon dioxide were delivered to the ventilator system before the ventilator or after the ventilator as a continuous flow, either directly into the inspiratory limb or into a mixing chamber positioned in the inspiratory limb. Both gases were delivered as above but synchronized with inspiration. Mixing conditions were evaluated using fast response chemiluminescence for nitric oxide and capnography for carbon dioxide analysis. Administration of nitric oxide and carbon dioxide directly into the inspiratory limb as a continuous flow or with a magnetic valve-controlled synchronized flow resulted in peak concentrations of 236% and 220%, respectively, of expected values. The use of a mixing chamber reduced these values to 104% and 102%, respectively. Administration of nitric oxide as a continuous flow into the tubing of an intermittent flow ventilator resulted in highly fluctuating inspiratory peak concentrations, which could be avoided with a mixing chamber.      

Content and contractile effect of arginine vasopressin in rat urinary bladder

The contractile response of normal male rat urinary bladders to exogenous arginine vasopressin (AVP) and the AVP content of normal and denervated bladders were investigated. In isolated detrusor strips, the maximal response to AVP was about 12% of the contraction elicited by KCl (124 mM), and the EC50 value was 1.03 +/- 0.13 x 10(-8) M. The response to transmural nerve stimulation was not affected by the presence of AVP. Addition of an AVP receptor antagonist strongly reduced the response to exogenous AVP, but did not affect contractions in response to nerve stimulation. In normal bladders, the concentration of immunoreactive (ir) AVP was 29 +/- 6.0 x 10(-15) mol/g. Three days after denervation the bladders had increased 2.4-fold in weight. At this time, the concentration of irAVP was not different from the control value, but the total content had increased significantly. Characterization of bladder irAVP by reverse-phase HPLC revealed that 66.5% of the total immunoreactivity eluted in the position of synthetic AVP. The results suggest a non-neuronal localization of bladder irAVP.     

Radiographic prediction of failure after fixation of cervical hip fracture

During 1984-1985, 410 patients with cervical hip fracture were randomized between 2 methods of internal fixation-a single nail (Rydell) or 2 LIH hook pins (LIH). The patients were followed-up prospectively for at least 2 years. Radiographs were taken after 1 week, 1, 3, 6, 12, and 24 months. The radiographs of the 295 paients alive 2 years postoperatively were examined by one of the authors. The sliding and the diversion of the pins and the nail in the anteroposterior projection and the diversion in the lateral projection were measured. In the failure group (non-union, late segmental collapse), the greatest sliding was noted within 1 month postoperatively and the diversion increased up to 3 months. Significant differences between the failure and the non-failure groups could be seen even after 1 week. We also found that the degree of sliding of the LIH pins and the Rydell nail 1 month postoperatively is comparable to the scintigraphic pattern 2 weeks postoperatively in predicting failure after nternal fixation of cervical hip fractures.     

Enhanced Intestinal Absorption of Oxytocin Peptide Analogues in the Absence of Pancreatic Juice in Pigs

Purpose. The present investigation was done to study the intestinal absorption of three oxytocin peptide analogues and to elucidate the role of pancreatic juice on their absorption. Methods. In conscious chronically catheterized pigs (6–8 weeks of age) plasma concentration of the peptides, [Mpa¹, D-Tyr(Ethyl)², Thr⁴, Orn⁸]-oxytocin (F314), [Mpa¹, D-Tyr(Ethyl)², Val⁴, D-Arg⁸]-oxytocin (CAT), and [Mpa¹, D-Tyr(Ethyl)², Thr⁴, Orn⁸, desGly⁹, carba⁶]-oxytocin (F327) after intraduodenal administration, during presence or diversion of the pancreatic juice via a pancreatic duct catheter, were determined by radioimmunoassay. The stability of the peptides to degradation was determined in vitro by incubation with activated pancreatic juice, chymotrypsin or trypsin, followed by reversed phase HPLC analyses. Results. All peptides were absorbed with a bioavailability of about 0.5% in the presence of pancreatic juice, but increased to 1.0%, 2.1%, and 13.5% for F314, CAT, and F327, respectively, when the pancreatic juice was diverted from the intestine. After incubation with pancreatic juice 95% of F314, 98% of F327, and 100% of CAT was found intact. When incubated with trypsin CAT remained intact while F314 and F327 were degraded by 54% and 46%, respectively. Incubation with purified chymotrypsin did not degrade the test peptides. Conclusions. The results indicate that the increased absorption of peptides observed under conditions of diverted pancreatic juice cannot only be explained by the absence of pancreatic enzymes, but also by changed absorptive properties in the gastrointestinal tract.