EFFECT OF ERYTHROCYTES AND PROSTACYCLIN PRODUCTION IN THE EFFECT OF FRUCTOSE AND SORBITOL ON PLATELET ACTIVATION IN HUMAN WHOLE BLOOD IN VITRO

We analyzed the in vitro effects of sorbitol and fructose on platelet function. Sorbitol and fructose increased platelet aggregation induced with adenosine diphosphate (ADP) or collagen in whole blood, but had no effect in platelet-rich plasma. The concentration that increased basal aggregation by 50% with ADP as the inducer was 12.89 ± 1.55 mmol/L for fructose, and 18.99 ± 2.01 mmol/L for sorbitol. When collagen was the inducer, these concentrations were 15.02 ± 0.98 mmol/L for fructose, and 12.94 ± 1.57 mmol/L for sorbitol. Both sugars increased, in a concentration-dependent way, the proaggregatory effect of erythrocytes, and erythrocyte uptake of adenosine. Time to uptake of 50% adenosine was 2.1 ± 0.3 min in control samples, 0.14 ± 0.01 min in the presence of fructose, and 0.23 ± 0.03 min with sorbitol. Both sugars reduced vascular prostacyclin synthesis, with 50% inhibitory concentrations of 26.48 ± 1.97 mmol/L for fructose, and 39.53 ± 2.81 mmol/L for sorbitol. Both sugars also increased arterial lipid peroxidation by 30% (sorbitol) and 23% (fructose). We conclude that these two sugars enhance platelet function and disrupt the thromboxane/prostacyclin ratio. © 1997 Elsevier Science Ltd     

Origin and content of methionyl-lysyl-bradykinin,lysyl-bradykinin and bradykinin in human urine

When human urine is collected in acid, three kinins, bradykinin (BK), lysyl-bradykinin (LBK, kallidin) and methionyl-lysyl-bradykinin (MLBK), are found. The identification of the MLBK was based on: (1) a chromatographic procedure which clearly separated it from BK and LBK, (2) its conversion by dipeptidyl aminopeptidase I to BK which was established by chromatographic and bioassay procedures, and (3) its amino acid composition. When the potent pepsin inhibitor, pepstasin, was added to the collection bottle in addition to the usual acid (to inhibit kininases), MLBK was either undetectable or reduced by 90 per cent. Pepstatin did not alter the excretion of BK or LBK. Addition of purified kininogen to acidified urine from a subject with a congenital absence of kininogen led to the formation of MLBK but no BK or LBK. In urine acidified after excretion, it is highly probable that MLBK is formed by uropepsin.     

216b. Technik der Laparoskopie

Ohne Zusammenfassung     

In-vitro renal shrinkage after hypertonic saline perfusion for organ removal during laparoscopic nephrectomy

BACKGROUND AND PURPOSE: To evaluate the possibility of shrinking the kidney by perfusion with hypertonic solution to facilitate organ removal in laparoscopic surgery. MATERIALS AND METHODS: After 18 open nephrectomies (ONs) in 9 pigs, one of four saline solutions (5%, 7.5%, 10%, and 15%) was infused through a catheter into the renal artery for 5 minutes in four kidneys each. The volumes and weights of the kidneys were measured before and after renal perfusion; the kidneys were then sent for histologic evaluation. Eight ONs were performed, and the kidneys were removed from the abdominal cavity in a plastic bag in order to mimic organ entrapment during laparoscopy. The kidneys were perfused with hypertonic solution and were again put in a plastic bag and removed from the same animal's abdomen through another incision. The incisions were measured with calipers before and after extraction of the unperfused and perfused organs. RESULTS: The kidneys that underwent perfusion with 5% saline had the greatest decrease in both weight and volume, an average of 16% and 17.8%, respectively. The average incision needed for extraction of unperfused kidneys was 44.9 mm (range 40-58 mm), whereas the mean size of the incision needed to remove perfused kidneys was 26.6 mm (range 20-30 mm) (P < 0.001). The relative reduction in the necessary incision size therefore was 44.3% (range 33.3%-55%). CONCLUSION: Perfusion with 5% saline is able to shrink the kidney volume slightly with mild histologic changes. In the pig, it is possible to decrease the renal incision necessary for kidney removal by 44% using this method.     

Mini-incisions by lombotomy or subcostal access in living kidney donors: a randomized trial comparing pain, safety, and quality of life

OBJECTIVES: The aim of this study was to compare two mini-incision techniques and judge the impact on the quality of life, pain, and safety of living kidney donors. PATIENTS AND METHODS: From March through September 2003, a prospective randomized study with 60 donors had nephrectomy performed - 30 through a lombotomy and another 30 patients underwent subcostal mini-incisions. The same anesthetic procedure was used for both groups. All patients were evaluated from baseline (T0) to day 90 after surgery. Pain evaluation included visual analog scale (VAS) and drug usage. To assess quality of life (QOL), the questionnaire SF-36 was used and surgical outcomes were also checked. RESULTS: Sixty patients (41.6 +/- 8.9 yr old) were included in the protocol. Regarding incision length and blood loss, no statistical difference was observed. However, irrespective to the site of the mini-incision, patients with body mass index (BMI) higher than 25 kg/m(2) had significantly longer incision length as well as higher blood loss. There were no complications. No significant difference in tramadol or in pain perception was observed between groups. QOL was also not different between groups, however, there was a significant loss with subsequent return to baseline levels. CONCLUSION: The position of the mini-incision (lombotomy or subcostal) has no significant impact on surgical outcomes, pain perception, and QOL of living kidney donors. Mini-incision techniques represent fast and safe approaches to perform nephrectomy in the healthy population. Special care must be taken in obese patients in order to minimize surgical complications.     

Elevated protein carbonyl and HIF‐1α levels in eyes with proliferative diabetic retinopathy

Purpose: To evaluate the role of protein carbonyls and hypoxia inducible factor‐1α (HIF‐1α) in diabetic eyes with proliferative diabetic retinopathy (PDR). Methods: Prospective consecutive controlled observational study was performed. Vitreous samples were collected at the start of the 3‐ppp vitrectomy. Protein carbonylation analysis was performed by Western blotting with antibody against 2,4‐Dinitrophenol (anti‐DNP), following derivatization of protein carbonyls with 2,4 Dinitrophenylhydrazine (DNHP). Protein carbonylation was quantified by scanning densitometry analysis and relativized to the total amount of protein into the ponceau staining of membranes. Vitreous HIF‐1 α was determined with ELISA in a subgroup of the samples. Thirty‐one eyes were operated due to PDR (study group). Of the 189 controls, 39 had nonproliferative diabetic retinopathy (non‐PDR), 111 retinal detachment (RD) and 39 macular hole/pucker (MH). Results: Comparison of eyes with PDR with controls revealed that the mean vitreous concentrations of protein carbonyls were significantly higher in the eyes affected with PDR being 242 ± 130 (SD) compared with non‐PDR controls 180 ± 142, nondiabetic eyes affected with RD 175 ± 131 and MH/pucker 140 ± 95 (p = 0.008, one‐way anova ). Mean HIF‐1α values were higher in eyes with PDR compared with controls (RD, MH/pucker); the values being 0.53 ± 0.34 (SEM; n = 4) and 0.13 ± 0.04 (SEM; n = 19), respectively (p = 0.009). Conclusions: Protein carbonyl and HIF‐1 α levels were significantly increased in the vitreous fluid of surgically treated eyes with PDR. Our findings suggest an association between increased intravitreal levels of protein carbonyls and the pathogenesis of PDR.     

Alcohol consumption and the incidence of type 2 diabetes: a 20-year follow-up of the Finnish twin cohort study

OBJECTIVE:The aim of this study was to investigate alcohol consumption in relation to the incidence of type 2 diabetes. RESEARCH DESIGN AND METHODS: The study population consisted of 22778 twins of the Finnish Twin Cohort. This cohort was compiled in 1975 and includes all same-sexed twins born in Finland before 1958. Information on alcohol, smoking, diet, physical activity, medical, and social conditions was obtained by questionnaires administered in 1975, 1981, and 1990. By record linkage to national registers of hospital discharge and prescribed medication, 580 incident cases of type 2 diabetes were identified during 20 years of follow-up. RESULTS: Moderate alcohol consumption (5-29.9 g/day in men and 5-19.9 g/day in women) tended to be associated with a reduced incidence of type 2 diabetes compared with low consumption (<5 g/day). The estimates were lower in overweight (BMI >or=25.0 kg/m(2)) subjects (relative risk 0.7, 95% CI 0.5-1.0 [men]; 0.6, 0.3-1.1 [women]). High alcohol consumption (>or=20 g/day) was associated with an increased incidence of type 2 diabetes in lean women (2.9, 1.1-7.5) but not in overweight women or in men. In women, binge drinking was associated with an increased incidence of type 2 diabetes (2.1, 1.0-4.4). Analyses of alcohol-discordant twin pairs supported a reduced risk in moderate consuming twins compared with their low-consuming cotwins (odds ratio 0.5, 95% CI 0.2-1.5). CONCLUSIONS: The results of this study suggested that moderate alcohol consumption may reduce the risk of type 2 diabetes. On the other hand, binge drinking and high alcohol consumption may increase the risk of type 2 diabetes in women.